[PATCH 0/6] 16G and multi size hugetlb page support on powerpc

[PATCH 0/6] 16G and multi size hugetlb page support on powerpc

[Jon Tollefson]

This patch set builds on Nick Piggin's patches for multi size and giant 
hugetlb page support of April 22.  The following set of patches adds 
support for 16G huge pages on ppc64 and support for multiple huge page 
sizes at the same time on ppc64.  Thus allowing 64K, 16M, and 16G huge 
pages given a POWER5+ or later machine.

New to this version of my patch is numerous bug fixes and cleanups, but 
the biggest change is the support for multiple huge page sizes on power.

patch 1: changes to generic hugetlb to enable 16G pages on power
patch 2: powerpc: adds function for allocating 16G pages
patch 3: powerpc: setups 16G page locations found in device tree
patch 4: powerpc: page definition support for 16G pages
patch 5: check for overflow when user space is 32bit
patch 6: powerpc: multiple huge page size support

Jon

[PATCH 0/6] 16G and multi size hugetlb page support on powerpc

[Jon Tollefson]

This patch set builds on Nick Piggin's patches for multi size and giant 
hugetlb page support of April 22.  The following set of patches adds 
support for 16G huge pages on ppc64 and support for multiple huge page 
sizes at the same time on ppc64.  Thus allowing 64K, 16M, and 16G huge 
pages given a POWER5+ or later machine.

New to this version of my patch is numerous bug fixes and cleanups, but 
the biggest change is the support for multiple huge page sizes on power.

patch 1: changes to generic hugetlb to enable 16G pages on power
patch 2: powerpc: adds function for allocating 16G pages
patch 3: powerpc: setups 16G page locations found in device tree
patch 4: powerpc: page definition support for 16G pages
patch 5: check for overflow when user space is 32bit
patch 6: powerpc: multiple huge page size support

Jon


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[PATCH 0/6] 16G and multi size hugetlb page support on powerpc

[Jon Tollefson]

This patch set builds on Nick Piggin's patches for multi size and giant 
hugetlb page support of April 22.  The following set of patches adds 
support for 16G huge pages on ppc64 and support for multiple huge page 
sizes at the same time on ppc64.  Thus allowing 64K, 16M, and 16G huge 
pages given a POWER5+ or later machine.

New to this version of my patch is numerous bug fixes and cleanups, but 
the biggest change is the support for multiple huge page sizes on power.

patch 1: changes to generic hugetlb to enable 16G pages on power
patch 2: powerpc: adds function for allocating 16G pages
patch 3: powerpc: setups 16G page locations found in device tree
patch 4: powerpc: page definition support for 16G pages
patch 5: check for overflow when user space is 32bit
patch 6: powerpc: multiple huge page size support

Jon

[PATCH 1/6 v2] allow arch specific function for allocating gigantic pages

[Jon Tollefson]

Allow alloc_bm_huge_page() to be overridden by architectures that can't
always use bootmem. This requires huge_boot_pages to be available for
use by this function. The 16G pages on ppc64 have to be reserved prior
to boot-time. The location of these pages are indicated in the device
tree.


A BUG_ON in huge_add_hstate is commented out in order to allow 64K huge
pages to continue to work on power.



Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 include/linux/hugetlb.h |   10 ++++++++++
 mm/hugetlb.c            |   15 ++++++---------
 2 files changed, 16 insertions(+), 9 deletions(-)


diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 8c47ca7..b550ec7 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -35,6 +35,7 @@ void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed);
 extern unsigned long hugepages_treat_as_movable;
 extern const unsigned long hugetlb_zero, hugetlb_infinity;
 extern int sysctl_hugetlb_shm_group;
+extern struct list_head huge_boot_pages;
 
 /* arch callbacks */
 
@@ -205,6 +206,14 @@ struct hstate {
 	unsigned int surplus_huge_pages_node[MAX_NUMNODES];
 };
 
+struct huge_bm_page {
+	struct list_head list;
+	struct hstate *hstate;
+};
+
+/* arch callback */
+int alloc_bm_huge_page(struct hstate *h);
+
 void __init huge_add_hstate(unsigned order);
 struct hstate *size_to_hstate(unsigned long size);
 
@@ -256,6 +265,7 @@ extern unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
 
 #else
 struct hstate {};
+#define alloc_bm_huge_page(h) NULL
 #define hstate_file(f) NULL
 #define hstate_vma(v) NULL
 #define hstate_inode(i) NULL
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5273f6c..efb5805 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -27,6 +27,7 @@ unsigned long max_huge_pages[HUGE_MAX_HSTATE];
 unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
 static gfp_t htlb_alloc_mask = GFP_HIGHUSER;
 unsigned long hugepages_treat_as_movable;
+struct list_head huge_boot_pages;
 
 static int max_hstate = 0;
 
@@ -533,14 +534,8 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma,
 	return page;
 }
 
-static __initdata LIST_HEAD(huge_boot_pages);
-
-struct huge_bm_page {
-	struct list_head list;
-	struct hstate *hstate;
-};
-
-static int __init alloc_bm_huge_page(struct hstate *h)
+/* Can be overriden by architectures */
+__attribute__((weak)) int alloc_bm_huge_page(struct hstate *h)
 {
 	struct huge_bm_page *m;
 	int nr_nodes = nodes_weight(node_online_map);
@@ -583,6 +578,8 @@ static void __init hugetlb_init_hstate(struct hstate *h)
 	unsigned long i;
 
 	/* Don't reinitialize lists if they have been already init'ed */
+	if (!huge_boot_pages.next)
+		INIT_LIST_HEAD(&huge_boot_pages);
 	if (!h->hugepage_freelists[0].next) {
 		for (i = 0; i < MAX_NUMNODES; ++i)
 			INIT_LIST_HEAD(&h->hugepage_freelists[i]);
@@ -664,7 +661,7 @@ void __init huge_add_hstate(unsigned order)
 		return;
 	}
 	BUG_ON(max_hstate >= HUGE_MAX_HSTATE);
-	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);
+/*	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);*/
 	h = &hstates[max_hstate++];
 	h->order = order;
 	h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);

[PATCH 1/6 v2] allow arch specific function for allocating gigantic pages

[Jon Tollefson]

Allow alloc_bm_huge_page() to be overridden by architectures that can't
always use bootmem. This requires huge_boot_pages to be available for
use by this function. The 16G pages on ppc64 have to be reserved prior
to boot-time. The location of these pages are indicated in the device
tree.


A BUG_ON in huge_add_hstate is commented out in order to allow 64K huge
pages to continue to work on power.



Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 include/linux/hugetlb.h |   10 ++++++++++
 mm/hugetlb.c            |   15 ++++++---------
 2 files changed, 16 insertions(+), 9 deletions(-)


diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 8c47ca7..b550ec7 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -35,6 +35,7 @@ void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed);
 extern unsigned long hugepages_treat_as_movable;
 extern const unsigned long hugetlb_zero, hugetlb_infinity;
 extern int sysctl_hugetlb_shm_group;
+extern struct list_head huge_boot_pages;
 
 /* arch callbacks */
 
@@ -205,6 +206,14 @@ struct hstate {
 	unsigned int surplus_huge_pages_node[MAX_NUMNODES];
 };
 
+struct huge_bm_page {
+	struct list_head list;
+	struct hstate *hstate;
+};
+
+/* arch callback */
+int alloc_bm_huge_page(struct hstate *h);
+
 void __init huge_add_hstate(unsigned order);
 struct hstate *size_to_hstate(unsigned long size);
 
@@ -256,6 +265,7 @@ extern unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
 
 #else
 struct hstate {};
+#define alloc_bm_huge_page(h) NULL
 #define hstate_file(f) NULL
 #define hstate_vma(v) NULL
 #define hstate_inode(i) NULL
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5273f6c..efb5805 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -27,6 +27,7 @@ unsigned long max_huge_pages[HUGE_MAX_HSTATE];
 unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
 static gfp_t htlb_alloc_mask = GFP_HIGHUSER;
 unsigned long hugepages_treat_as_movable;
+struct list_head huge_boot_pages;
 
 static int max_hstate = 0;
 
@@ -533,14 +534,8 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma,
 	return page;
 }
 
-static __initdata LIST_HEAD(huge_boot_pages);
-
-struct huge_bm_page {
-	struct list_head list;
-	struct hstate *hstate;
-};
-
-static int __init alloc_bm_huge_page(struct hstate *h)
+/* Can be overriden by architectures */
+__attribute__((weak)) int alloc_bm_huge_page(struct hstate *h)
 {
 	struct huge_bm_page *m;
 	int nr_nodes = nodes_weight(node_online_map);
@@ -583,6 +578,8 @@ static void __init hugetlb_init_hstate(struct hstate *h)
 	unsigned long i;
 
 	/* Don't reinitialize lists if they have been already init'ed */
+	if (!huge_boot_pages.next)
+		INIT_LIST_HEAD(&huge_boot_pages);
 	if (!h->hugepage_freelists[0].next) {
 		for (i = 0; i < MAX_NUMNODES; ++i)
 			INIT_LIST_HEAD(&h->hugepage_freelists[i]);
@@ -664,7 +661,7 @@ void __init huge_add_hstate(unsigned order)
 		return;
 	}
 	BUG_ON(max_hstate >= HUGE_MAX_HSTATE);
-	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);
+/*	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);*/
 	h = &hstates[max_hstate++];
 	h->order = order;
 	h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);




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[PATCH 1/6 v2] allow arch specific function for allocating gigantic pages

[Jon Tollefson]

Allow alloc_bm_huge_page() to be overridden by architectures that can't
always use bootmem. This requires huge_boot_pages to be available for
use by this function. The 16G pages on ppc64 have to be reserved prior
to boot-time. The location of these pages are indicated in the device
tree.


A BUG_ON in huge_add_hstate is commented out in order to allow 64K huge
pages to continue to work on power.



Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 include/linux/hugetlb.h |   10 ++++++++++
 mm/hugetlb.c            |   15 ++++++---------
 2 files changed, 16 insertions(+), 9 deletions(-)


diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 8c47ca7..b550ec7 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -35,6 +35,7 @@ void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed);
 extern unsigned long hugepages_treat_as_movable;
 extern const unsigned long hugetlb_zero, hugetlb_infinity;
 extern int sysctl_hugetlb_shm_group;
+extern struct list_head huge_boot_pages;
 
 /* arch callbacks */
 
@@ -205,6 +206,14 @@ struct hstate {
 	unsigned int surplus_huge_pages_node[MAX_NUMNODES];
 };
 
+struct huge_bm_page {
+	struct list_head list;
+	struct hstate *hstate;
+};
+
+/* arch callback */
+int alloc_bm_huge_page(struct hstate *h);
+
 void __init huge_add_hstate(unsigned order);
 struct hstate *size_to_hstate(unsigned long size);
 
@@ -256,6 +265,7 @@ extern unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
 
 #else
 struct hstate {};
+#define alloc_bm_huge_page(h) NULL
 #define hstate_file(f) NULL
 #define hstate_vma(v) NULL
 #define hstate_inode(i) NULL
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5273f6c..efb5805 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -27,6 +27,7 @@ unsigned long max_huge_pages[HUGE_MAX_HSTATE];
 unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
 static gfp_t htlb_alloc_mask = GFP_HIGHUSER;
 unsigned long hugepages_treat_as_movable;
+struct list_head huge_boot_pages;
 
 static int max_hstate = 0;
 
@@ -533,14 +534,8 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma,
 	return page;
 }
 
-static __initdata LIST_HEAD(huge_boot_pages);
-
-struct huge_bm_page {
-	struct list_head list;
-	struct hstate *hstate;
-};
-
-static int __init alloc_bm_huge_page(struct hstate *h)
+/* Can be overriden by architectures */
+__attribute__((weak)) int alloc_bm_huge_page(struct hstate *h)
 {
 	struct huge_bm_page *m;
 	int nr_nodes = nodes_weight(node_online_map);
@@ -583,6 +578,8 @@ static void __init hugetlb_init_hstate(struct hstate *h)
 	unsigned long i;
 
 	/* Don't reinitialize lists if they have been already init'ed */
+	if (!huge_boot_pages.next)
+		INIT_LIST_HEAD(&huge_boot_pages);
 	if (!h->hugepage_freelists[0].next) {
 		for (i = 0; i < MAX_NUMNODES; ++i)
 			INIT_LIST_HEAD(&h->hugepage_freelists[i]);
@@ -664,7 +661,7 @@ void __init huge_add_hstate(unsigned order)
 		return;
 	}
 	BUG_ON(max_hstate >= HUGE_MAX_HSTATE);
-	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);
+/*	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);*/
 	h = &hstates[max_hstate++];
 	h->order = order;
 	h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);

Re: [PATCH 1/6 v2] allow arch specific function for allocating gigantic pages

[Nick Piggin]

On Tue, May 13, 2008 at 12:19:36PM -0500, Jon Tollefson wrote:
> Allow alloc_bm_huge_page() to be overridden by architectures that can't
> always use bootmem. This requires huge_boot_pages to be available for
> use by this function. The 16G pages on ppc64 have to be reserved prior
> to boot-time. The location of these pages are indicated in the device
> tree.

That looks fine. I wonder if we should call it something else now?
Anyway, nevermind naming for the moment.


> A BUG_ON in huge_add_hstate is commented out in order to allow 64K huge
> pages to continue to work on power.

Fine. I'll remove the BUG_ON completely from where it was
introduced.


> Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
> ---
> 
> include/linux/hugetlb.h |   10 ++++++++++
> mm/hugetlb.c            |   15 ++++++---------
> 2 files changed, 16 insertions(+), 9 deletions(-)
> 
> 
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index 8c47ca7..b550ec7 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -35,6 +35,7 @@ void hugetlb_unreserve_pages(struct inode *inode, long 
> offset, long freed);
> extern unsigned long hugepages_treat_as_movable;
> extern const unsigned long hugetlb_zero, hugetlb_infinity;
> extern int sysctl_hugetlb_shm_group;
> +extern struct list_head huge_boot_pages;
> 
> /* arch callbacks */
> 
> @@ -205,6 +206,14 @@ struct hstate {
> 	unsigned int surplus_huge_pages_node[MAX_NUMNODES];
> };
> 
> +struct huge_bm_page {
> +	struct list_head list;
> +	struct hstate *hstate;
> +};
> +
> +/* arch callback */
> +int alloc_bm_huge_page(struct hstate *h);
> +
> void __init huge_add_hstate(unsigned order);
> struct hstate *size_to_hstate(unsigned long size);
> 
> @@ -256,6 +265,7 @@ extern unsigned long 
> sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
> 
> #else
> struct hstate {};
> +#define alloc_bm_huge_page(h) NULL
> #define hstate_file(f) NULL
> #define hstate_vma(v) NULL
> #define hstate_inode(i) NULL
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 5273f6c..efb5805 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -27,6 +27,7 @@ unsigned long max_huge_pages[HUGE_MAX_HSTATE];
> unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
> static gfp_t htlb_alloc_mask = GFP_HIGHUSER;
> unsigned long hugepages_treat_as_movable;
> +struct list_head huge_boot_pages;
> 
> static int max_hstate = 0;
> 
> @@ -533,14 +534,8 @@ static struct page *alloc_huge_page(struct 
> vm_area_struct *vma,
> 	return page;
> }
> 
> -static __initdata LIST_HEAD(huge_boot_pages);
> -
> -struct huge_bm_page {
> -	struct list_head list;
> -	struct hstate *hstate;
> -};
> -
> -static int __init alloc_bm_huge_page(struct hstate *h)
> +/* Can be overriden by architectures */
> +__attribute__((weak)) int alloc_bm_huge_page(struct hstate *h)
> {
> 	struct huge_bm_page *m;
> 	int nr_nodes = nodes_weight(node_online_map);
> @@ -583,6 +578,8 @@ static void __init hugetlb_init_hstate(struct hstate *h)
> 	unsigned long i;
> 
> 	/* Don't reinitialize lists if they have been already init'ed */
> +	if (!huge_boot_pages.next)
> +		INIT_LIST_HEAD(&huge_boot_pages);
> 	if (!h->hugepage_freelists[0].next) {
> 		for (i = 0; i < MAX_NUMNODES; ++i)
> 			INIT_LIST_HEAD(&h->hugepage_freelists[i]);
> @@ -664,7 +661,7 @@ void __init huge_add_hstate(unsigned order)
> 		return;
> 	}
> 	BUG_ON(max_hstate >= HUGE_MAX_HSTATE);
> -	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);
> +/*	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);*/
> 	h = &hstates[max_hstate++];
> 	h->order = order;
> 	h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);
> 
> 
> 

Re: [PATCH 1/6 v2] allow arch specific function for allocating gigantic pages

[Nick Piggin]

On Tue, May 13, 2008 at 12:19:36PM -0500, Jon Tollefson wrote:
> Allow alloc_bm_huge_page() to be overridden by architectures that can't
> always use bootmem. This requires huge_boot_pages to be available for
> use by this function. The 16G pages on ppc64 have to be reserved prior
> to boot-time. The location of these pages are indicated in the device
> tree.

That looks fine. I wonder if we should call it something else now?
Anyway, nevermind naming for the moment.


> A BUG_ON in huge_add_hstate is commented out in order to allow 64K huge
> pages to continue to work on power.

Fine. I'll remove the BUG_ON completely from where it was
introduced.


> Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
> ---
> 
> include/linux/hugetlb.h |   10 ++++++++++
> mm/hugetlb.c            |   15 ++++++---------
> 2 files changed, 16 insertions(+), 9 deletions(-)
> 
> 
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index 8c47ca7..b550ec7 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -35,6 +35,7 @@ void hugetlb_unreserve_pages(struct inode *inode, long 
> offset, long freed);
> extern unsigned long hugepages_treat_as_movable;
> extern const unsigned long hugetlb_zero, hugetlb_infinity;
> extern int sysctl_hugetlb_shm_group;
> +extern struct list_head huge_boot_pages;
> 
> /* arch callbacks */
> 
> @@ -205,6 +206,14 @@ struct hstate {
> 	unsigned int surplus_huge_pages_node[MAX_NUMNODES];
> };
> 
> +struct huge_bm_page {
> +	struct list_head list;
> +	struct hstate *hstate;
> +};
> +
> +/* arch callback */
> +int alloc_bm_huge_page(struct hstate *h);
> +
> void __init huge_add_hstate(unsigned order);
> struct hstate *size_to_hstate(unsigned long size);
> 
> @@ -256,6 +265,7 @@ extern unsigned long 
> sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
> 
> #else
> struct hstate {};
> +#define alloc_bm_huge_page(h) NULL
> #define hstate_file(f) NULL
> #define hstate_vma(v) NULL
> #define hstate_inode(i) NULL
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 5273f6c..efb5805 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -27,6 +27,7 @@ unsigned long max_huge_pages[HUGE_MAX_HSTATE];
> unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
> static gfp_t htlb_alloc_mask = GFP_HIGHUSER;
> unsigned long hugepages_treat_as_movable;
> +struct list_head huge_boot_pages;
> 
> static int max_hstate = 0;
> 
> @@ -533,14 +534,8 @@ static struct page *alloc_huge_page(struct 
> vm_area_struct *vma,
> 	return page;
> }
> 
> -static __initdata LIST_HEAD(huge_boot_pages);
> -
> -struct huge_bm_page {
> -	struct list_head list;
> -	struct hstate *hstate;
> -};
> -
> -static int __init alloc_bm_huge_page(struct hstate *h)
> +/* Can be overriden by architectures */
> +__attribute__((weak)) int alloc_bm_huge_page(struct hstate *h)
> {
> 	struct huge_bm_page *m;
> 	int nr_nodes = nodes_weight(node_online_map);
> @@ -583,6 +578,8 @@ static void __init hugetlb_init_hstate(struct hstate *h)
> 	unsigned long i;
> 
> 	/* Don't reinitialize lists if they have been already init'ed */
> +	if (!huge_boot_pages.next)
> +		INIT_LIST_HEAD(&huge_boot_pages);
> 	if (!h->hugepage_freelists[0].next) {
> 		for (i = 0; i < MAX_NUMNODES; ++i)
> 			INIT_LIST_HEAD(&h->hugepage_freelists[i]);
> @@ -664,7 +661,7 @@ void __init huge_add_hstate(unsigned order)
> 		return;
> 	}
> 	BUG_ON(max_hstate >= HUGE_MAX_HSTATE);
> -	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);
> +/*	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);*/
> 	h = &hstates[max_hstate++];
> 	h->order = order;
> 	h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);
> 
> 
> 

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Re: [PATCH 1/6 v2] allow arch specific function for allocating gigantic pages

[Nick Piggin]

On Tue, May 13, 2008 at 12:19:36PM -0500, Jon Tollefson wrote:
> Allow alloc_bm_huge_page() to be overridden by architectures that can't
> always use bootmem. This requires huge_boot_pages to be available for
> use by this function. The 16G pages on ppc64 have to be reserved prior
> to boot-time. The location of these pages are indicated in the device
> tree.

That looks fine. I wonder if we should call it something else now?
Anyway, nevermind naming for the moment.


> A BUG_ON in huge_add_hstate is commented out in order to allow 64K huge
> pages to continue to work on power.

Fine. I'll remove the BUG_ON completely from where it was
introduced.


> Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
> ---
> 
> include/linux/hugetlb.h |   10 ++++++++++
> mm/hugetlb.c            |   15 ++++++---------
> 2 files changed, 16 insertions(+), 9 deletions(-)
> 
> 
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index 8c47ca7..b550ec7 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -35,6 +35,7 @@ void hugetlb_unreserve_pages(struct inode *inode, long 
> offset, long freed);
> extern unsigned long hugepages_treat_as_movable;
> extern const unsigned long hugetlb_zero, hugetlb_infinity;
> extern int sysctl_hugetlb_shm_group;
> +extern struct list_head huge_boot_pages;
> 
> /* arch callbacks */
> 
> @@ -205,6 +206,14 @@ struct hstate {
> 	unsigned int surplus_huge_pages_node[MAX_NUMNODES];
> };
> 
> +struct huge_bm_page {
> +	struct list_head list;
> +	struct hstate *hstate;
> +};
> +
> +/* arch callback */
> +int alloc_bm_huge_page(struct hstate *h);
> +
> void __init huge_add_hstate(unsigned order);
> struct hstate *size_to_hstate(unsigned long size);
> 
> @@ -256,6 +265,7 @@ extern unsigned long 
> sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
> 
> #else
> struct hstate {};
> +#define alloc_bm_huge_page(h) NULL
> #define hstate_file(f) NULL
> #define hstate_vma(v) NULL
> #define hstate_inode(i) NULL
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 5273f6c..efb5805 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -27,6 +27,7 @@ unsigned long max_huge_pages[HUGE_MAX_HSTATE];
> unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
> static gfp_t htlb_alloc_mask = GFP_HIGHUSER;
> unsigned long hugepages_treat_as_movable;
> +struct list_head huge_boot_pages;
> 
> static int max_hstate = 0;
> 
> @@ -533,14 +534,8 @@ static struct page *alloc_huge_page(struct 
> vm_area_struct *vma,
> 	return page;
> }
> 
> -static __initdata LIST_HEAD(huge_boot_pages);
> -
> -struct huge_bm_page {
> -	struct list_head list;
> -	struct hstate *hstate;
> -};
> -
> -static int __init alloc_bm_huge_page(struct hstate *h)
> +/* Can be overriden by architectures */
> +__attribute__((weak)) int alloc_bm_huge_page(struct hstate *h)
> {
> 	struct huge_bm_page *m;
> 	int nr_nodes = nodes_weight(node_online_map);
> @@ -583,6 +578,8 @@ static void __init hugetlb_init_hstate(struct hstate *h)
> 	unsigned long i;
> 
> 	/* Don't reinitialize lists if they have been already init'ed */
> +	if (!huge_boot_pages.next)
> +		INIT_LIST_HEAD(&huge_boot_pages);
> 	if (!h->hugepage_freelists[0].next) {
> 		for (i = 0; i < MAX_NUMNODES; ++i)
> 			INIT_LIST_HEAD(&h->hugepage_freelists[i]);
> @@ -664,7 +661,7 @@ void __init huge_add_hstate(unsigned order)
> 		return;
> 	}
> 	BUG_ON(max_hstate >= HUGE_MAX_HSTATE);
> -	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);
> +/*	BUG_ON(order < HPAGE_SHIFT - PAGE_SHIFT);*/
> 	h = &hstates[max_hstate++];
> 	h->order = order;
> 	h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);
> 
> 
> 

[PATCH 2/6 v2] powerpc: function for allocating gigantic pages

[Jon Tollefson]

The 16G page locations have been saved during early boot in an array.
The alloc_bm_huge_page() function adds a page from here to the
huge_boot_pages list.


Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hugetlbpage.c |   22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 26f212f..383b3b2 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -29,6 +29,12 @@
 
 #define NUM_LOW_AREAS	(0x100000000UL >> SID_SHIFT)
 #define NUM_HIGH_AREAS	(PGTABLE_RANGE >> HTLB_AREA_SHIFT)
+#define MAX_NUMBER_GPAGES	1024
+
+/* Tracks the 16G pages after the device tree is scanned and before the
+ *  huge_boot_pages list is ready.  */
+static unsigned long gpage_freearray[MAX_NUMBER_GPAGES];
+static unsigned nr_gpages;
 
 unsigned int hugepte_shift;
 #define PTRS_PER_HUGEPTE	(1 << hugepte_shift)
@@ -104,6 +110,22 @@ pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
 }
 #endif
 
+/* Moves the gigantic page addresses from the temporary list to the
+  * huge_boot_pages list.
+ */
+int alloc_bm_huge_page(struct hstate *h)
+{
+	struct huge_bm_page *m;
+	if (nr_gpages == 0)
+		return 0;
+	m = phys_to_virt(gpage_freearray[--nr_gpages]);
+	gpage_freearray[nr_gpages] = 0;
+	list_add(&m->list, &huge_boot_pages);
+	m->hstate = h;
+	return 1;
+}
+
+
 /* Modelled after find_linux_pte() */
 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 {

[PATCH 2/6 v2] powerpc: function for allocating gigantic pages

[Jon Tollefson]

The 16G page locations have been saved during early boot in an array.
The alloc_bm_huge_page() function adds a page from here to the
huge_boot_pages list.


Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hugetlbpage.c |   22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 26f212f..383b3b2 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -29,6 +29,12 @@
 
 #define NUM_LOW_AREAS	(0x100000000UL >> SID_SHIFT)
 #define NUM_HIGH_AREAS	(PGTABLE_RANGE >> HTLB_AREA_SHIFT)
+#define MAX_NUMBER_GPAGES	1024
+
+/* Tracks the 16G pages after the device tree is scanned and before the
+ *  huge_boot_pages list is ready.  */
+static unsigned long gpage_freearray[MAX_NUMBER_GPAGES];
+static unsigned nr_gpages;
 
 unsigned int hugepte_shift;
 #define PTRS_PER_HUGEPTE	(1 << hugepte_shift)
@@ -104,6 +110,22 @@ pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
 }
 #endif
 
+/* Moves the gigantic page addresses from the temporary list to the
+  * huge_boot_pages list.
+ */
+int alloc_bm_huge_page(struct hstate *h)
+{
+	struct huge_bm_page *m;
+	if (nr_gpages == 0)
+		return 0;
+	m = phys_to_virt(gpage_freearray[--nr_gpages]);
+	gpage_freearray[nr_gpages] = 0;
+	list_add(&m->list, &huge_boot_pages);
+	m->hstate = h;
+	return 1;
+}
+
+
 /* Modelled after find_linux_pte() */
 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 {




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[PATCH 2/6 v2] powerpc: function for allocating gigantic pages

[Jon Tollefson]

The 16G page locations have been saved during early boot in an array.
The alloc_bm_huge_page() function adds a page from here to the
huge_boot_pages list.


Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hugetlbpage.c |   22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 26f212f..383b3b2 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -29,6 +29,12 @@
 
 #define NUM_LOW_AREAS	(0x100000000UL >> SID_SHIFT)
 #define NUM_HIGH_AREAS	(PGTABLE_RANGE >> HTLB_AREA_SHIFT)
+#define MAX_NUMBER_GPAGES	1024
+
+/* Tracks the 16G pages after the device tree is scanned and before the
+ *  huge_boot_pages list is ready.  */
+static unsigned long gpage_freearray[MAX_NUMBER_GPAGES];
+static unsigned nr_gpages;
 
 unsigned int hugepte_shift;
 #define PTRS_PER_HUGEPTE	(1 << hugepte_shift)
@@ -104,6 +110,22 @@ pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
 }
 #endif
 
+/* Moves the gigantic page addresses from the temporary list to the
+  * huge_boot_pages list.
+ */
+int alloc_bm_huge_page(struct hstate *h)
+{
+	struct huge_bm_page *m;
+	if (nr_gpages == 0)
+		return 0;
+	m = phys_to_virt(gpage_freearray[--nr_gpages]);
+	gpage_freearray[nr_gpages] = 0;
+	list_add(&m->list, &huge_boot_pages);
+	m->hstate = h;
+	return 1;
+}
+
+
 /* Modelled after find_linux_pte() */
 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 {

[PATCH 3/6 v2] powerpc: scan device tree and save gigantic page locations

[Jon Tollefson]

The 16G huge pages have to be reserved in the HMC prior to boot. The
location of the pages are placed in the device tree.   This patch adds
code to scan the device tree during very early boot and save these page
locations until hugetlbfs is ready for them.



Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hash_utils_64.c  |   44 ++++++++++++++++++++++++++++++++++++++-
 arch/powerpc/mm/hugetlbpage.c    |   16 ++++++++++++++
 include/asm-powerpc/mmu-hash64.h |    2 +
 3 files changed, 61 insertions(+), 1 deletion(-)



diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index a83dfa3..133d6e2 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -67,6 +67,7 @@
 
 #define KB (1024)
 #define MB (1024*KB)
+#define GB (1024L*MB)
 
 /*
  * Note:  pte   --> Linux PTE
@@ -302,6 +303,44 @@ static int __init htab_dt_scan_page_sizes(unsigned long node,
 	return 0;
 }
 
+/* Scan for 16G memory blocks that have been set aside for huge pages
+ * and reserve those blocks for 16G huge pages.
+ */
+static int __init htab_dt_scan_hugepage_blocks(unsigned long node,
+					const char *uname, int depth,
+					void *data) {
+	char *type = of_get_flat_dt_prop(node, "device_type", NULL);
+	unsigned long *addr_prop;
+	u32 *page_count_prop;
+	unsigned int expected_pages;
+	long unsigned int phys_addr;
+	long unsigned int block_size;
+
+	/* We are scanning "memory" nodes only */
+	if (type == NULL || strcmp(type, "memory") != 0)
+		return 0;
+
+	/* This property is the log base 2 of the number of virtual pages that
+	 * will represent this memory block. */
+	page_count_prop = of_get_flat_dt_prop(node, "ibm,expected#pages", NULL);
+	if (page_count_prop == NULL)
+		return 0;
+	expected_pages = (1 << page_count_prop[0]);
+	addr_prop = of_get_flat_dt_prop(node, "reg", NULL);
+	if (addr_prop == NULL)
+		return 0;
+	phys_addr = addr_prop[0];
+	block_size = addr_prop[1];
+	if (block_size != (16 * GB))
+		return 0;
+	printk(KERN_INFO "Huge page(16GB) memory: "
+			"addr = 0x%lX size = 0x%lX pages = %d\n",
+			phys_addr, block_size, expected_pages);
+	lmb_reserve(phys_addr, block_size * expected_pages);
+	add_gpage(phys_addr, block_size, expected_pages);
+	return 0;
+}
+
 static void __init htab_init_page_sizes(void)
 {
 	int rc;
@@ -370,7 +409,10 @@ static void __init htab_init_page_sizes(void)
 	       mmu_psize_defs[mmu_io_psize].shift);
 
 #ifdef CONFIG_HUGETLB_PAGE
-	/* Init large page size. Currently, we pick 16M or 1M depending
+	/* Reserve 16G huge page memory sections for huge pages */
+	of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL);
+
+/* Init large page size. Currently, we pick 16M or 1M depending
 	 * on what is available
 	 */
 	if (mmu_psize_defs[MMU_PAGE_16M].shift)
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 383b3b2..a27b80c 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -110,6 +110,22 @@ pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
 }
 #endif
 
+/* Build list of addresses of gigantic pages.  This function is used in early
+ * boot before the buddy or bootmem allocator is setup.
+ */
+void add_gpage(unsigned long addr, unsigned long page_size,
+	unsigned long number_of_pages)
+{
+	if (!addr)
+		return;
+	while (number_of_pages > 0) {
+		gpage_freearray[nr_gpages] = addr;
+		nr_gpages++;
+		number_of_pages--;
+		addr += page_size;
+	}
+}
+
 /* Moves the gigantic page addresses from the temporary list to the
   * huge_boot_pages list.
  */
diff --git a/include/asm-powerpc/mmu-hash64.h b/include/asm-powerpc/mmu-hash64.h
index 2864fa3..db1276a 100644
--- a/include/asm-powerpc/mmu-hash64.h
+++ b/include/asm-powerpc/mmu-hash64.h
@@ -279,6 +279,8 @@ extern int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
 			     unsigned long pstart, unsigned long mode,
 			     int psize, int ssize);
 extern void set_huge_psize(int psize);
+extern void add_gpage(unsigned long addr, unsigned long page_size,
+			  unsigned long number_of_pages);
 extern void demote_segment_4k(struct mm_struct *mm, unsigned long addr);
 
 extern void htab_initialize(void);

[PATCH 3/6 v2] powerpc: scan device tree and save gigantic page locations

[Jon Tollefson]

The 16G huge pages have to be reserved in the HMC prior to boot. The
location of the pages are placed in the device tree.   This patch adds
code to scan the device tree during very early boot and save these page
locations until hugetlbfs is ready for them.



Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hash_utils_64.c  |   44 ++++++++++++++++++++++++++++++++++++++-
 arch/powerpc/mm/hugetlbpage.c    |   16 ++++++++++++++
 include/asm-powerpc/mmu-hash64.h |    2 +
 3 files changed, 61 insertions(+), 1 deletion(-)



diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index a83dfa3..133d6e2 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -67,6 +67,7 @@
 
 #define KB (1024)
 #define MB (1024*KB)
+#define GB (1024L*MB)
 
 /*
  * Note:  pte   --> Linux PTE
@@ -302,6 +303,44 @@ static int __init htab_dt_scan_page_sizes(unsigned long node,
 	return 0;
 }
 
+/* Scan for 16G memory blocks that have been set aside for huge pages
+ * and reserve those blocks for 16G huge pages.
+ */
+static int __init htab_dt_scan_hugepage_blocks(unsigned long node,
+					const char *uname, int depth,
+					void *data) {
+	char *type = of_get_flat_dt_prop(node, "device_type", NULL);
+	unsigned long *addr_prop;
+	u32 *page_count_prop;
+	unsigned int expected_pages;
+	long unsigned int phys_addr;
+	long unsigned int block_size;
+
+	/* We are scanning "memory" nodes only */
+	if (type == NULL || strcmp(type, "memory") != 0)
+		return 0;
+
+	/* This property is the log base 2 of the number of virtual pages that
+	 * will represent this memory block. */
+	page_count_prop = of_get_flat_dt_prop(node, "ibm,expected#pages", NULL);
+	if (page_count_prop == NULL)
+		return 0;
+	expected_pages = (1 << page_count_prop[0]);
+	addr_prop = of_get_flat_dt_prop(node, "reg", NULL);
+	if (addr_prop == NULL)
+		return 0;
+	phys_addr = addr_prop[0];
+	block_size = addr_prop[1];
+	if (block_size != (16 * GB))
+		return 0;
+	printk(KERN_INFO "Huge page(16GB) memory: "
+			"addr = 0x%lX size = 0x%lX pages = %d\n",
+			phys_addr, block_size, expected_pages);
+	lmb_reserve(phys_addr, block_size * expected_pages);
+	add_gpage(phys_addr, block_size, expected_pages);
+	return 0;
+}
+
 static void __init htab_init_page_sizes(void)
 {
 	int rc;
@@ -370,7 +409,10 @@ static void __init htab_init_page_sizes(void)
 	       mmu_psize_defs[mmu_io_psize].shift);
 
 #ifdef CONFIG_HUGETLB_PAGE
-	/* Init large page size. Currently, we pick 16M or 1M depending
+	/* Reserve 16G huge page memory sections for huge pages */
+	of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL);
+
+/* Init large page size. Currently, we pick 16M or 1M depending
 	 * on what is available
 	 */
 	if (mmu_psize_defs[MMU_PAGE_16M].shift)
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 383b3b2..a27b80c 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -110,6 +110,22 @@ pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
 }
 #endif
 
+/* Build list of addresses of gigantic pages.  This function is used in early
+ * boot before the buddy or bootmem allocator is setup.
+ */
+void add_gpage(unsigned long addr, unsigned long page_size,
+	unsigned long number_of_pages)
+{
+	if (!addr)
+		return;
+	while (number_of_pages > 0) {
+		gpage_freearray[nr_gpages] = addr;
+		nr_gpages++;
+		number_of_pages--;
+		addr += page_size;
+	}
+}
+
 /* Moves the gigantic page addresses from the temporary list to the
   * huge_boot_pages list.
  */
diff --git a/include/asm-powerpc/mmu-hash64.h b/include/asm-powerpc/mmu-hash64.h
index 2864fa3..db1276a 100644
--- a/include/asm-powerpc/mmu-hash64.h
+++ b/include/asm-powerpc/mmu-hash64.h
@@ -279,6 +279,8 @@ extern int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
 			     unsigned long pstart, unsigned long mode,
 			     int psize, int ssize);
 extern void set_huge_psize(int psize);
+extern void add_gpage(unsigned long addr, unsigned long page_size,
+			  unsigned long number_of_pages);
 extern void demote_segment_4k(struct mm_struct *mm, unsigned long addr);
 
 extern void htab_initialize(void);


--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[PATCH 3/6 v2] powerpc: scan device tree and save gigantic page locations

[Jon Tollefson]

The 16G huge pages have to be reserved in the HMC prior to boot. The
location of the pages are placed in the device tree.   This patch adds
code to scan the device tree during very early boot and save these page
locations until hugetlbfs is ready for them.



Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hash_utils_64.c  |   44 ++++++++++++++++++++++++++++++++++++++-
 arch/powerpc/mm/hugetlbpage.c    |   16 ++++++++++++++
 include/asm-powerpc/mmu-hash64.h |    2 +
 3 files changed, 61 insertions(+), 1 deletion(-)



diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index a83dfa3..133d6e2 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -67,6 +67,7 @@
 
 #define KB (1024)
 #define MB (1024*KB)
+#define GB (1024L*MB)
 
 /*
  * Note:  pte   --> Linux PTE
@@ -302,6 +303,44 @@ static int __init htab_dt_scan_page_sizes(unsigned long node,
 	return 0;
 }
 
+/* Scan for 16G memory blocks that have been set aside for huge pages
+ * and reserve those blocks for 16G huge pages.
+ */
+static int __init htab_dt_scan_hugepage_blocks(unsigned long node,
+					const char *uname, int depth,
+					void *data) {
+	char *type = of_get_flat_dt_prop(node, "device_type", NULL);
+	unsigned long *addr_prop;
+	u32 *page_count_prop;
+	unsigned int expected_pages;
+	long unsigned int phys_addr;
+	long unsigned int block_size;
+
+	/* We are scanning "memory" nodes only */
+	if (type == NULL || strcmp(type, "memory") != 0)
+		return 0;
+
+	/* This property is the log base 2 of the number of virtual pages that
+	 * will represent this memory block. */
+	page_count_prop = of_get_flat_dt_prop(node, "ibm,expected#pages", NULL);
+	if (page_count_prop == NULL)
+		return 0;
+	expected_pages = (1 << page_count_prop[0]);
+	addr_prop = of_get_flat_dt_prop(node, "reg", NULL);
+	if (addr_prop == NULL)
+		return 0;
+	phys_addr = addr_prop[0];
+	block_size = addr_prop[1];
+	if (block_size != (16 * GB))
+		return 0;
+	printk(KERN_INFO "Huge page(16GB) memory: "
+			"addr = 0x%lX size = 0x%lX pages = %d\n",
+			phys_addr, block_size, expected_pages);
+	lmb_reserve(phys_addr, block_size * expected_pages);
+	add_gpage(phys_addr, block_size, expected_pages);
+	return 0;
+}
+
 static void __init htab_init_page_sizes(void)
 {
 	int rc;
@@ -370,7 +409,10 @@ static void __init htab_init_page_sizes(void)
 	       mmu_psize_defs[mmu_io_psize].shift);
 
 #ifdef CONFIG_HUGETLB_PAGE
-	/* Init large page size. Currently, we pick 16M or 1M depending
+	/* Reserve 16G huge page memory sections for huge pages */
+	of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL);
+
+/* Init large page size. Currently, we pick 16M or 1M depending
 	 * on what is available
 	 */
 	if (mmu_psize_defs[MMU_PAGE_16M].shift)
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 383b3b2..a27b80c 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -110,6 +110,22 @@ pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
 }
 #endif
 
+/* Build list of addresses of gigantic pages.  This function is used in early
+ * boot before the buddy or bootmem allocator is setup.
+ */
+void add_gpage(unsigned long addr, unsigned long page_size,
+	unsigned long number_of_pages)
+{
+	if (!addr)
+		return;
+	while (number_of_pages > 0) {
+		gpage_freearray[nr_gpages] = addr;
+		nr_gpages++;
+		number_of_pages--;
+		addr += page_size;
+	}
+}
+
 /* Moves the gigantic page addresses from the temporary list to the
   * huge_boot_pages list.
  */
diff --git a/include/asm-powerpc/mmu-hash64.h b/include/asm-powerpc/mmu-hash64.h
index 2864fa3..db1276a 100644
--- a/include/asm-powerpc/mmu-hash64.h
+++ b/include/asm-powerpc/mmu-hash64.h
@@ -279,6 +279,8 @@ extern int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
 			     unsigned long pstart, unsigned long mode,
 			     int psize, int ssize);
 extern void set_huge_psize(int psize);
+extern void add_gpage(unsigned long addr, unsigned long page_size,
+			  unsigned long number_of_pages);
 extern void demote_segment_4k(struct mm_struct *mm, unsigned long addr);
 
 extern void htab_initialize(void);

[PATCH 4/6 v2] powerpc: define page support for 16G pages

[Jon Tollefson]

The huge page size is defined for 16G pages.  If a hugepagesz of 16G is
specified at boot-time then it becomes the huge page size instead of
the default 16M.

The change in pgtable-64K.h is to the macro
pte_iterate_hashed_subpages to make the increment to va (the 1
being shifted) be a long so that it is not shifted to 0.  Otherwise it
would create an infinite loop when the shift value is for a 16G page
(when base page size is 64K).



Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hugetlbpage.c     |   62 ++++++++++++++++++++++++++------------
 include/asm-powerpc/pgtable-64k.h |    2 -
 2 files changed, 45 insertions(+), 19 deletions(-)

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index a27b80c..063ec36 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -24,8 +24,9 @@
 #include <asm/cputable.h>
 #include <asm/spu.h>
 
-#define HPAGE_SHIFT_64K	16
-#define HPAGE_SHIFT_16M	24
+#define PAGE_SHIFT_64K	16
+#define PAGE_SHIFT_16M	24
+#define PAGE_SHIFT_16G	34
 
 #define NUM_LOW_AREAS	(0x100000000UL >> SID_SHIFT)
 #define NUM_HIGH_AREAS	(PGTABLE_RANGE >> HTLB_AREA_SHIFT)
@@ -95,7 +96,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 static inline
 pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
 {
-	if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
+	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
 		return pmd_offset(pud, addr);
 	else
 		return (pmd_t *) pud;
@@ -103,7 +104,7 @@ pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
 static inline
 pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
 {
-	if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
+	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
 		return pmd_alloc(mm, pud, addr);
 	else
 		return (pmd_t *) pud;
@@ -260,7 +261,7 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 			continue;
 		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
 #else
-		if (HPAGE_SHIFT == HPAGE_SHIFT_64K) {
+		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
 			if (pud_none_or_clear_bad(pud))
 				continue;
 			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
@@ -591,20 +592,40 @@ void set_huge_psize(int psize)
 {
 	/* Check that it is a page size supported by the hardware and
 	 * that it fits within pagetable limits. */
-	if (mmu_psize_defs[psize].shift && mmu_psize_defs[psize].shift < SID_SHIFT &&
+	if (mmu_psize_defs[psize].shift &&
+		mmu_psize_defs[psize].shift < SID_SHIFT_1T &&
 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
-			mmu_psize_defs[psize].shift == HPAGE_SHIFT_64K)) {
+		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
+		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
+		/* Return if huge page size is the same as the
+		 * base page size. */
+		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
+			return;
+
 		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
 		mmu_huge_psize = psize;
-#ifdef CONFIG_PPC_64K_PAGES
-		hugepte_shift = (PMD_SHIFT-HPAGE_SHIFT);
-#else
-		if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
-			hugepte_shift = (PMD_SHIFT-HPAGE_SHIFT);
-		else
-			hugepte_shift = (PUD_SHIFT-HPAGE_SHIFT);
-#endif
 
+		switch (HPAGE_SHIFT) {
+		case PAGE_SHIFT_64K:
+		    /* We only allow 64k hpages with 4k base page,
+		     * which was checked above, and always put them
+		     * at the PMD */
+		    hugepte_shift = PMD_SHIFT;
+		    break;
+		case PAGE_SHIFT_16M:
+		    /* 16M pages can be at two different levels
+		     * of pagestables based on base page size */
+		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
+			    hugepte_shift = PMD_SHIFT;
+		    else /* 4k base page */
+			    hugepte_shift = PUD_SHIFT;
+		    break;
+		case PAGE_SHIFT_16G:
+		    /* 16G pages are always at PGD level */
+		    hugepte_shift = PGDIR_SHIFT;
+		    break;
+		}
+		hugepte_shift -= HPAGE_SHIFT;
 	} else
 		HPAGE_SHIFT = 0;
 }
@@ -620,17 +641,22 @@ static int __init hugepage_setup_sz(char *str)
 	shift = __ffs(size);
 	switch (shift) {
 #ifndef CONFIG_PPC_64K_PAGES
-	case HPAGE_SHIFT_64K:
+	case PAGE_SHIFT_64K:
 		mmu_psize = MMU_PAGE_64K;
 		break;
 #endif
-	case HPAGE_SHIFT_16M:
+	case PAGE_SHIFT_16M:
 		mmu_psize = MMU_PAGE_16M;
 		break;
+	case PAGE_SHIFT_16G:
+		mmu_psize = MMU_PAGE_16G;
+		break;
 	}
 
-	if (mmu_psize >=0 && mmu_psize_defs[mmu_psize].shift)
+	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
 		set_huge_psize(mmu_psize);
+		huge_add_hstate(shift - PAGE_SHIFT);
+	}
 	else
 		printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size);
 
diff --git a/include/asm-powerpc/pgtable-64k.h b/include/asm-powerpc/pgtable-64k.h
index 1cbd6b3..55f0861 100644
--- a/include/asm-powerpc/pgtable-64k.h
+++ b/include/asm-powerpc/pgtable-64k.h
@@ -125,7 +125,7 @@ static inline struct subpage_prot_table *pgd_subpage_prot(pgd_t *pgd)
                 unsigned __split = (psize == MMU_PAGE_4K ||                 \
 				    psize == MMU_PAGE_64K_AP);              \
                 shift = mmu_psize_defs[psize].shift;                        \
-	        for (index = 0; va < __end; index++, va += (1 << shift)) {  \
+		for (index = 0; va < __end; index++, va += (1L << shift)) { \
 		        if (!__split || __rpte_sub_valid(rpte, index)) do { \
 
 #define pte_iterate_hashed_end() } while(0); } } while(0)

[PATCH 4/6 v2] powerpc: define page support for 16G pages

[Jon Tollefson]

The huge page size is defined for 16G pages.  If a hugepagesz of 16G is
specified at boot-time then it becomes the huge page size instead of
the default 16M.

The change in pgtable-64K.h is to the macro
pte_iterate_hashed_subpages to make the increment to va (the 1
being shifted) be a long so that it is not shifted to 0.  Otherwise it
would create an infinite loop when the shift value is for a 16G page
(when base page size is 64K).



Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hugetlbpage.c     |   62 ++++++++++++++++++++++++++------------
 include/asm-powerpc/pgtable-64k.h |    2 -
 2 files changed, 45 insertions(+), 19 deletions(-)

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index a27b80c..063ec36 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -24,8 +24,9 @@
 #include <asm/cputable.h>
 #include <asm/spu.h>
 
-#define HPAGE_SHIFT_64K	16
-#define HPAGE_SHIFT_16M	24
+#define PAGE_SHIFT_64K	16
+#define PAGE_SHIFT_16M	24
+#define PAGE_SHIFT_16G	34
 
 #define NUM_LOW_AREAS	(0x100000000UL >> SID_SHIFT)
 #define NUM_HIGH_AREAS	(PGTABLE_RANGE >> HTLB_AREA_SHIFT)
@@ -95,7 +96,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 static inline
 pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
 {
-	if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
+	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
 		return pmd_offset(pud, addr);
 	else
 		return (pmd_t *) pud;
@@ -103,7 +104,7 @@ pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
 static inline
 pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
 {
-	if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
+	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
 		return pmd_alloc(mm, pud, addr);
 	else
 		return (pmd_t *) pud;
@@ -260,7 +261,7 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 			continue;
 		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
 #else
-		if (HPAGE_SHIFT == HPAGE_SHIFT_64K) {
+		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
 			if (pud_none_or_clear_bad(pud))
 				continue;
 			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
@@ -591,20 +592,40 @@ void set_huge_psize(int psize)
 {
 	/* Check that it is a page size supported by the hardware and
 	 * that it fits within pagetable limits. */
-	if (mmu_psize_defs[psize].shift && mmu_psize_defs[psize].shift < SID_SHIFT &&
+	if (mmu_psize_defs[psize].shift &&
+		mmu_psize_defs[psize].shift < SID_SHIFT_1T &&
 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
-			mmu_psize_defs[psize].shift == HPAGE_SHIFT_64K)) {
+		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
+		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
+		/* Return if huge page size is the same as the
+		 * base page size. */
+		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
+			return;
+
 		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
 		mmu_huge_psize = psize;
-#ifdef CONFIG_PPC_64K_PAGES
-		hugepte_shift = (PMD_SHIFT-HPAGE_SHIFT);
-#else
-		if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
-			hugepte_shift = (PMD_SHIFT-HPAGE_SHIFT);
-		else
-			hugepte_shift = (PUD_SHIFT-HPAGE_SHIFT);
-#endif
 
+		switch (HPAGE_SHIFT) {
+		case PAGE_SHIFT_64K:
+		    /* We only allow 64k hpages with 4k base page,
+		     * which was checked above, and always put them
+		     * at the PMD */
+		    hugepte_shift = PMD_SHIFT;
+		    break;
+		case PAGE_SHIFT_16M:
+		    /* 16M pages can be at two different levels
+		     * of pagestables based on base page size */
+		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
+			    hugepte_shift = PMD_SHIFT;
+		    else /* 4k base page */
+			    hugepte_shift = PUD_SHIFT;
+		    break;
+		case PAGE_SHIFT_16G:
+		    /* 16G pages are always at PGD level */
+		    hugepte_shift = PGDIR_SHIFT;
+		    break;
+		}
+		hugepte_shift -= HPAGE_SHIFT;
 	} else
 		HPAGE_SHIFT = 0;
 }
@@ -620,17 +641,22 @@ static int __init hugepage_setup_sz(char *str)
 	shift = __ffs(size);
 	switch (shift) {
 #ifndef CONFIG_PPC_64K_PAGES
-	case HPAGE_SHIFT_64K:
+	case PAGE_SHIFT_64K:
 		mmu_psize = MMU_PAGE_64K;
 		break;
 #endif
-	case HPAGE_SHIFT_16M:
+	case PAGE_SHIFT_16M:
 		mmu_psize = MMU_PAGE_16M;
 		break;
+	case PAGE_SHIFT_16G:
+		mmu_psize = MMU_PAGE_16G;
+		break;
 	}
 
-	if (mmu_psize >=0 && mmu_psize_defs[mmu_psize].shift)
+	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
 		set_huge_psize(mmu_psize);
+		huge_add_hstate(shift - PAGE_SHIFT);
+	}
 	else
 		printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size);
 
diff --git a/include/asm-powerpc/pgtable-64k.h b/include/asm-powerpc/pgtable-64k.h
index 1cbd6b3..55f0861 100644
--- a/include/asm-powerpc/pgtable-64k.h
+++ b/include/asm-powerpc/pgtable-64k.h
@@ -125,7 +125,7 @@ static inline struct subpage_prot_table *pgd_subpage_prot(pgd_t *pgd)
                 unsigned __split = (psize == MMU_PAGE_4K ||                 \
 				    psize == MMU_PAGE_64K_AP);              \
                 shift = mmu_psize_defs[psize].shift;                        \
-	        for (index = 0; va < __end; index++, va += (1 << shift)) {  \
+		for (index = 0; va < __end; index++, va += (1L << shift)) { \
 		        if (!__split || __rpte_sub_valid(rpte, index)) do { \
 
 #define pte_iterate_hashed_end() } while(0); } } while(0)


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[PATCH 4/6 v2] powerpc: define page support for 16G pages

[Jon Tollefson]

The huge page size is defined for 16G pages.  If a hugepagesz of 16G is
specified at boot-time then it becomes the huge page size instead of
the default 16M.

The change in pgtable-64K.h is to the macro
pte_iterate_hashed_subpages to make the increment to va (the 1
being shifted) be a long so that it is not shifted to 0.  Otherwise it
would create an infinite loop when the shift value is for a 16G page
(when base page size is 64K).



Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hugetlbpage.c     |   62 ++++++++++++++++++++++++++------------
 include/asm-powerpc/pgtable-64k.h |    2 -
 2 files changed, 45 insertions(+), 19 deletions(-)

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index a27b80c..063ec36 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -24,8 +24,9 @@
 #include <asm/cputable.h>
 #include <asm/spu.h>
 
-#define HPAGE_SHIFT_64K	16
-#define HPAGE_SHIFT_16M	24
+#define PAGE_SHIFT_64K	16
+#define PAGE_SHIFT_16M	24
+#define PAGE_SHIFT_16G	34
 
 #define NUM_LOW_AREAS	(0x100000000UL >> SID_SHIFT)
 #define NUM_HIGH_AREAS	(PGTABLE_RANGE >> HTLB_AREA_SHIFT)
@@ -95,7 +96,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 static inline
 pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
 {
-	if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
+	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
 		return pmd_offset(pud, addr);
 	else
 		return (pmd_t *) pud;
@@ -103,7 +104,7 @@ pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
 static inline
 pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
 {
-	if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
+	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
 		return pmd_alloc(mm, pud, addr);
 	else
 		return (pmd_t *) pud;
@@ -260,7 +261,7 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 			continue;
 		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
 #else
-		if (HPAGE_SHIFT == HPAGE_SHIFT_64K) {
+		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
 			if (pud_none_or_clear_bad(pud))
 				continue;
 			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
@@ -591,20 +592,40 @@ void set_huge_psize(int psize)
 {
 	/* Check that it is a page size supported by the hardware and
 	 * that it fits within pagetable limits. */
-	if (mmu_psize_defs[psize].shift && mmu_psize_defs[psize].shift < SID_SHIFT &&
+	if (mmu_psize_defs[psize].shift &&
+		mmu_psize_defs[psize].shift < SID_SHIFT_1T &&
 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
-			mmu_psize_defs[psize].shift == HPAGE_SHIFT_64K)) {
+		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
+		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
+		/* Return if huge page size is the same as the
+		 * base page size. */
+		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
+			return;
+
 		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
 		mmu_huge_psize = psize;
-#ifdef CONFIG_PPC_64K_PAGES
-		hugepte_shift = (PMD_SHIFT-HPAGE_SHIFT);
-#else
-		if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
-			hugepte_shift = (PMD_SHIFT-HPAGE_SHIFT);
-		else
-			hugepte_shift = (PUD_SHIFT-HPAGE_SHIFT);
-#endif
 
+		switch (HPAGE_SHIFT) {
+		case PAGE_SHIFT_64K:
+		    /* We only allow 64k hpages with 4k base page,
+		     * which was checked above, and always put them
+		     * at the PMD */
+		    hugepte_shift = PMD_SHIFT;
+		    break;
+		case PAGE_SHIFT_16M:
+		    /* 16M pages can be at two different levels
+		     * of pagestables based on base page size */
+		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
+			    hugepte_shift = PMD_SHIFT;
+		    else /* 4k base page */
+			    hugepte_shift = PUD_SHIFT;
+		    break;
+		case PAGE_SHIFT_16G:
+		    /* 16G pages are always at PGD level */
+		    hugepte_shift = PGDIR_SHIFT;
+		    break;
+		}
+		hugepte_shift -= HPAGE_SHIFT;
 	} else
 		HPAGE_SHIFT = 0;
 }
@@ -620,17 +641,22 @@ static int __init hugepage_setup_sz(char *str)
 	shift = __ffs(size);
 	switch (shift) {
 #ifndef CONFIG_PPC_64K_PAGES
-	case HPAGE_SHIFT_64K:
+	case PAGE_SHIFT_64K:
 		mmu_psize = MMU_PAGE_64K;
 		break;
 #endif
-	case HPAGE_SHIFT_16M:
+	case PAGE_SHIFT_16M:
 		mmu_psize = MMU_PAGE_16M;
 		break;
+	case PAGE_SHIFT_16G:
+		mmu_psize = MMU_PAGE_16G;
+		break;
 	}
 
-	if (mmu_psize >=0 && mmu_psize_defs[mmu_psize].shift)
+	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
 		set_huge_psize(mmu_psize);
+		huge_add_hstate(shift - PAGE_SHIFT);
+	}
 	else
 		printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size);
 
diff --git a/include/asm-powerpc/pgtable-64k.h b/include/asm-powerpc/pgtable-64k.h
index 1cbd6b3..55f0861 100644
--- a/include/asm-powerpc/pgtable-64k.h
+++ b/include/asm-powerpc/pgtable-64k.h
@@ -125,7 +125,7 @@ static inline struct subpage_prot_table *pgd_subpage_prot(pgd_t *pgd)
                 unsigned __split = (psize == MMU_PAGE_4K ||                 \
 				    psize == MMU_PAGE_64K_AP);              \
                 shift = mmu_psize_defs[psize].shift;                        \
-	        for (index = 0; va < __end; index++, va += (1 << shift)) {  \
+		for (index = 0; va < __end; index++, va += (1L << shift)) { \
 		        if (!__split || __rpte_sub_valid(rpte, index)) do { \
 
 #define pte_iterate_hashed_end() } while(0); } } while(0)

[PATCH 5/6 v2] check for overflow

[Jon Tollefson]

Adds a check for an overflow in the filesystem size so if someone is
checking with statfs() on a 16G hugetlbfs  in a 32bit binary that it
will report back EOVERFLOW instead of a size of 0.

Are other places that need a similar check?  I had tried a similar
check in put_compat_statfs64 too but it didn't seem to generate an
EOVERFLOW in my test case.


Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 fs/compat.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)


diff --git a/fs/compat.c b/fs/compat.c
index 2ce4456..6eb6aad 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -196,8 +196,8 @@ static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *
 {
 	
 	if (sizeof ubuf->f_blocks == 4) {
-		if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail) &
-		    0xffffffff00000000ULL)
+		if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
+		     kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
 			return -EOVERFLOW;
 		/* f_files and f_ffree may be -1; it's okay
 		 * to stuff that into 32 bits */

[PATCH 5/6 v2] check for overflow

[Jon Tollefson]

Adds a check for an overflow in the filesystem size so if someone is
checking with statfs() on a 16G hugetlbfs  in a 32bit binary that it
will report back EOVERFLOW instead of a size of 0.

Are other places that need a similar check?  I had tried a similar
check in put_compat_statfs64 too but it didn't seem to generate an
EOVERFLOW in my test case.


Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 fs/compat.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)


diff --git a/fs/compat.c b/fs/compat.c
index 2ce4456..6eb6aad 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -196,8 +196,8 @@ static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *
 {
 	
 	if (sizeof ubuf->f_blocks == 4) {
-		if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail) &
-		    0xffffffff00000000ULL)
+		if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
+		     kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
 			return -EOVERFLOW;
 		/* f_files and f_ffree may be -1; it's okay
 		 * to stuff that into 32 bits */


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[PATCH 5/6 v2] check for overflow

[Jon Tollefson]

Adds a check for an overflow in the filesystem size so if someone is
checking with statfs() on a 16G hugetlbfs  in a 32bit binary that it
will report back EOVERFLOW instead of a size of 0.

Are other places that need a similar check?  I had tried a similar
check in put_compat_statfs64 too but it didn't seem to generate an
EOVERFLOW in my test case.


Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 fs/compat.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)


diff --git a/fs/compat.c b/fs/compat.c
index 2ce4456..6eb6aad 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -196,8 +196,8 @@ static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *
 {
 	
 	if (sizeof ubuf->f_blocks == 4) {
-		if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail) &
-		    0xffffffff00000000ULL)
+		if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
+		     kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
 			return -EOVERFLOW;
 		/* f_files and f_ffree may be -1; it's okay
 		 * to stuff that into 32 bits */

[PATCH 6/6] powerpc: support multiple huge page sizes

[Jon Tollefson]

Instead of using the variable mmu_huge_psize to keep track of the huge
page size we use an array of MMU_PAGE_* values.  For each supported
huge page size we need to know the hugepte_shift value and have a
pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
functions so that they know which huge page size they should use.

The hugepage sizes 16M and 64K are setup(if available on the
hardware) so that they don't have to be set on the boot cmd line in
order to use them.  The number of 16G pages have to be specified at
boot-time though (e.g. hugepagesz=16G hugepages=5).


Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hash_utils_64.c  |    9 -
 arch/powerpc/mm/hugetlbpage.c    |  267 +++++++++++++++++++++++++--------------
 arch/powerpc/mm/init_64.c        |    8 -
 arch/powerpc/mm/tlb_64.c         |    2 
 include/asm-powerpc/mmu-hash64.h |    4 
 include/asm-powerpc/page_64.h    |    1 
 include/asm-powerpc/pgalloc-64.h |    4 
 7 files changed, 187 insertions(+), 108 deletions(-)


--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -99,7 +99,6 @@ int mmu_kernel_ssize = MMU_SEGSIZE_256M;
 int mmu_highuser_ssize = MMU_SEGSIZE_256M;
 u16 mmu_slb_size = 64;
 #ifdef CONFIG_HUGETLB_PAGE
-int mmu_huge_psize = MMU_PAGE_16M;
 unsigned int HPAGE_SHIFT;
 #endif
 #ifdef CONFIG_PPC_64K_PAGES
@@ -412,15 +411,15 @@ static void __init htab_init_page_sizes(void)
 	/* Reserve 16G huge page memory sections for huge pages */
 	of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL);
 
-/* Init large page size. Currently, we pick 16M or 1M depending
+/* Set default large page size. Currently, we pick 16M or 1M depending
 	 * on what is available
 	 */
 	if (mmu_psize_defs[MMU_PAGE_16M].shift)
-		set_huge_psize(MMU_PAGE_16M);
+		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_16M].shift;
 	/* With 4k/4level pagetables, we can't (for now) cope with a
 	 * huge page size < PMD_SIZE */
 	else if (mmu_psize_defs[MMU_PAGE_1M].shift)
-		set_huge_psize(MMU_PAGE_1M);
+		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_1M].shift;
 #endif /* CONFIG_HUGETLB_PAGE */
 }
 
@@ -819,7 +818,7 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
 
 #ifdef CONFIG_HUGETLB_PAGE
 	/* Handle hugepage regions */
-	if (HPAGE_SHIFT && psize == mmu_huge_psize) {
+	if (HPAGE_SHIFT && mmu_huge_psizes[psize]) {
 		DBG_LOW(" -> huge page !\n");
 		return hash_huge_page(mm, access, ea, vsid, local, trap);
 	}
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 063ec36..61ce875 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -37,15 +37,30 @@
 static unsigned long gpage_freearray[MAX_NUMBER_GPAGES];
 static unsigned nr_gpages;
 
-unsigned int hugepte_shift;
-#define PTRS_PER_HUGEPTE	(1 << hugepte_shift)
-#define HUGEPTE_TABLE_SIZE	(sizeof(pte_t) << hugepte_shift)
+/* Array of valid huge page sizes - non-zero value(hugepte_shift) is
+ * stored for the huge page sizes that are valid.
+ */
+unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
+
+#define hugepte_shift			mmu_huge_psizes
+#define PTRS_PER_HUGEPTE(psize)		(1 << hugepte_shift[psize])
+#define HUGEPTE_TABLE_SIZE(psize)	(sizeof(pte_t) << hugepte_shift[psize])
+
+#define HUGEPD_SHIFT(psize)		(mmu_psize_to_shift(psize) \
+						+ hugepte_shift[psize])
+#define HUGEPD_SIZE(psize)		(1UL << HUGEPD_SHIFT(psize))
+#define HUGEPD_MASK(psize)		(~(HUGEPD_SIZE(psize)-1))
 
-#define HUGEPD_SHIFT		(HPAGE_SHIFT + hugepte_shift)
-#define HUGEPD_SIZE		(1UL << HUGEPD_SHIFT)
-#define HUGEPD_MASK		(~(HUGEPD_SIZE-1))
+/* Subtract one from array size because we don't need a cache for 4K since
+ * is not a huge page size */
+#define huge_pgtable_cache(psize)	(pgtable_cache[HUGEPTE_CACHE_NUM \
+							+ psize-1])
+#define HUGEPTE_CACHE_NAME(psize)	(huge_pgtable_cache_name[psize])
 
-#define huge_pgtable_cache	(pgtable_cache[HUGEPTE_CACHE_NUM])
+static const char *huge_pgtable_cache_name[MMU_PAGE_COUNT] = {
+	"unused_4K", "hugepte_cache_64K", "unused_64K_AP",
+	"hugepte_cache_1M", "hugepte_cache_16M", "hugepte_cache_16G"
+};
 
 /* Flag to mark huge PD pointers.  This means pmd_bad() and pud_bad()
  * will choke on pointers to hugepte tables, which is handy for
@@ -56,24 +71,49 @@ typedef struct { unsigned long pd; } hugepd_t;
 
 #define hugepd_none(hpd)	((hpd).pd == 0)
 
+static inline int shift_to_mmu_psize(unsigned int shift)
+{
+	switch (shift) {
+#ifndef CONFIG_PPC_64K_PAGES
+	case PAGE_SHIFT_64K:
+	    return MMU_PAGE_64K;
+#endif
+	case PAGE_SHIFT_16M:
+	    return MMU_PAGE_16M;
+	case PAGE_SHIFT_16G:
+	    return MMU_PAGE_16G;
+	}
+	return -1;
+}
+
+static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize)
+{
+	if (mmu_psize_defs[mmu_psize].shift)
+		return mmu_psize_defs[mmu_psize].shift;
+	BUG();
+}
+
 static inline pte_t *hugepd_page(hugepd_t hpd)
 {
 	BUG_ON(!(hpd.pd & HUGEPD_OK));
 	return (pte_t *)(hpd.pd & ~HUGEPD_OK);
 }
 
-static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr)
+static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr,
+				    struct hstate *hstate)
 {
-	unsigned long idx = ((addr >> HPAGE_SHIFT) & (PTRS_PER_HUGEPTE-1));
+	unsigned int shift = huge_page_shift(hstate);
+	int psize = shift_to_mmu_psize(shift);
+	unsigned long idx = ((addr >> shift) & (PTRS_PER_HUGEPTE(psize)-1));
 	pte_t *dir = hugepd_page(*hpdp);
 
 	return dir + idx;
 }
 
 static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
-			   unsigned long address)
+			   unsigned long address, unsigned int psize)
 {
-	pte_t *new = kmem_cache_alloc(huge_pgtable_cache,
+	pte_t *new = kmem_cache_alloc(huge_pgtable_cache(psize),
 				      GFP_KERNEL|__GFP_REPEAT);
 
 	if (! new)
@@ -81,7 +121,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 
 	spin_lock(&mm->page_table_lock);
 	if (!hugepd_none(*hpdp))
-		kmem_cache_free(huge_pgtable_cache, new);
+		kmem_cache_free(huge_pgtable_cache(psize), new);
 	else
 		hpdp->pd = (unsigned long)new | HUGEPD_OK;
 	spin_unlock(&mm->page_table_lock);
@@ -90,21 +130,22 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 
 /* Base page size affects how we walk hugetlb page tables */
 #ifdef CONFIG_PPC_64K_PAGES
-#define hpmd_offset(pud, addr)		pmd_offset(pud, addr)
-#define hpmd_alloc(mm, pud, addr)	pmd_alloc(mm, pud, addr)
+#define hpmd_offset(pud, addr, h)	pmd_offset(pud, addr)
+#define hpmd_alloc(mm, pud, addr, h)	pmd_alloc(mm, pud, addr)
 #else
 static inline
-pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
+pmd_t *hpmd_offset(pud_t *pud, unsigned long addr, struct hstate *hstate)
 {
-	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
+	if (huge_page_shift(hstate) == PAGE_SHIFT_64K)
 		return pmd_offset(pud, addr);
 	else
 		return (pmd_t *) pud;
 }
 static inline
-pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
+pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr,
+		  struct hstate *hstate)
 {
-	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
+	if (huge_page_shift(hstate) == PAGE_SHIFT_64K)
 		return pmd_alloc(mm, pud, addr);
 	else
 		return (pmd_t *) pud;
@@ -130,7 +171,7 @@ void add_gpage(unsigned long addr, unsigned long page_size,
 /* Moves the gigantic page addresses from the temporary list to the
   * huge_boot_pages list.
  */
-int alloc_bm_huge_page(struct hstate *h)
+int alloc_bm_huge_page(struct hstate *hstate)
 {
 	struct huge_bm_page *m;
 	if (nr_gpages == 0)
@@ -138,7 +179,7 @@ int alloc_bm_huge_page(struct hstate *h)
 	m = phys_to_virt(gpage_freearray[--nr_gpages]);
 	gpage_freearray[nr_gpages] = 0;
 	list_add(&m->list, &huge_boot_pages);
-	m->hstate = h;
+	m->hstate = hstate;
 	return 1;
 }
 
@@ -150,17 +191,25 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	pud_t *pu;
 	pmd_t *pm;
 
-	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
+	unsigned int psize;
+	unsigned int shift;
+	unsigned long sz;
+	struct hstate *hstate;
+	psize = get_slice_psize(mm, addr);
+	shift = mmu_psize_to_shift(psize);
+	sz = ((1UL) << shift);
+	hstate = size_to_hstate(sz);
 
-	addr &= HPAGE_MASK;
+	addr &= hstate->mask;
 
 	pg = pgd_offset(mm, addr);
 	if (!pgd_none(*pg)) {
 		pu = pud_offset(pg, addr);
 		if (!pud_none(*pu)) {
-			pm = hpmd_offset(pu, addr);
+			pm = hpmd_offset(pu, addr, hstate);
 			if (!pmd_none(*pm))
-				return hugepte_offset((hugepd_t *)pm, addr);
+				return hugepte_offset((hugepd_t *)pm, addr,
+						      hstate);
 		}
 	}
 
@@ -173,16 +222,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz
 	pud_t *pu;
 	pmd_t *pm;
 	hugepd_t *hpdp = NULL;
+	struct hstate *hstate;
+	unsigned int psize;
+	hstate = size_to_hstate(sz);
 
-	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
+	psize = get_slice_psize(mm, addr);
+	BUG_ON(!mmu_huge_psizes[psize]);
 
-	addr &= HPAGE_MASK;
+	addr &= hstate->mask;
 
 	pg = pgd_offset(mm, addr);
 	pu = pud_alloc(mm, pg, addr);
 
 	if (pu) {
-		pm = hpmd_alloc(mm, pu, addr);
+		pm = hpmd_alloc(mm, pu, addr, hstate);
 		if (pm)
 			hpdp = (hugepd_t *)pm;
 	}
@@ -190,10 +243,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz
 	if (! hpdp)
 		return NULL;
 
-	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
+	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize))
 		return NULL;
 
-	return hugepte_offset(hpdp, addr);
+	return hugepte_offset(hpdp, addr, hstate);
 }
 
 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
@@ -201,19 +254,22 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 	return 0;
 }
 
-static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
+static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp,
+			       unsigned int psize)
 {
 	pte_t *hugepte = hugepd_page(*hpdp);
 
 	hpdp->pd = 0;
 	tlb->need_flush = 1;
-	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
+	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte,
+						 HUGEPTE_CACHE_NUM+psize-1,
 						 PGF_CACHENUM_MASK));
 }
 
 static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
 				   unsigned long addr, unsigned long end,
-				   unsigned long floor, unsigned long ceiling)
+				   unsigned long floor, unsigned long ceiling,
+				   unsigned int psize)
 {
 	pmd_t *pmd;
 	unsigned long next;
@@ -225,7 +281,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
 		next = pmd_addr_end(addr, end);
 		if (pmd_none(*pmd))
 			continue;
-		free_hugepte_range(tlb, (hugepd_t *)pmd);
+		free_hugepte_range(tlb, (hugepd_t *)pmd, psize);
 	} while (pmd++, addr = next, addr != end);
 
 	start &= PUD_MASK;
@@ -251,6 +307,9 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 	pud_t *pud;
 	unsigned long next;
 	unsigned long start;
+	unsigned int shift;
+	unsigned int psize = get_slice_psize(tlb->mm, addr);
+	shift = mmu_psize_to_shift(psize);
 
 	start = addr;
 	pud = pud_offset(pgd, addr);
@@ -259,16 +318,18 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 #ifdef CONFIG_PPC_64K_PAGES
 		if (pud_none_or_clear_bad(pud))
 			continue;
-		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
+		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling,
+				       psize);
 #else
-		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
+		if (shift == PAGE_SHIFT_64K) {
 			if (pud_none_or_clear_bad(pud))
 				continue;
-			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
+			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
+					       ceiling, psize);
 		} else {
 			if (pud_none(*pud))
 				continue;
-			free_hugepte_range(tlb, (hugepd_t *)pud);
+			free_hugepte_range(tlb, (hugepd_t *)pud, psize);
 		}
 #endif
 	} while (pud++, addr = next, addr != end);
@@ -336,27 +397,29 @@ void hugetlb_free_pgd_range(struct mmu_gather **tlb,
 	 * now has no other vmas using it, so can be freed, we don't
 	 * bother to round floor or end up - the tests don't need that.
 	 */
+	unsigned int psize = get_slice_psize((*tlb)->mm, addr);
 
-	addr &= HUGEPD_MASK;
+	addr &= HUGEPD_MASK(psize);
 	if (addr < floor) {
-		addr += HUGEPD_SIZE;
+		addr += HUGEPD_SIZE(psize);
 		if (!addr)
 			return;
 	}
 	if (ceiling) {
-		ceiling &= HUGEPD_MASK;
+		ceiling &= HUGEPD_MASK(psize);
 		if (!ceiling)
 			return;
 	}
 	if (end - 1 > ceiling - 1)
-		end -= HUGEPD_SIZE;
+		end -= HUGEPD_SIZE(psize);
 	if (addr > end - 1)
 		return;
 
 	start = addr;
 	pgd = pgd_offset((*tlb)->mm, addr);
 	do {
-		BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
+		psize = get_slice_psize((*tlb)->mm, addr);
+		BUG_ON(!mmu_huge_psizes[psize]);
 		next = pgd_addr_end(addr, end);
 		if (pgd_none_or_clear_bad(pgd))
 			continue;
@@ -373,7 +436,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 		 * necessary anymore if we make hpte_need_flush() get the
 		 * page size from the slices
 		 */
-		pte_update(mm, addr & HPAGE_MASK, ptep, ~0UL, 1);
+		unsigned int psize = get_slice_psize(mm, addr);
+		unsigned int shift = mmu_psize_to_shift(psize);
+		unsigned long sz;
+		sz = ((1UL) << shift);
+		struct hstate *hstate = size_to_hstate(sz);
+		pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1);
 	}
 	*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
 }
@@ -390,14 +458,19 @@ follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
 {
 	pte_t *ptep;
 	struct page *page;
+	unsigned int mmu_psize = get_slice_psize(mm, address);
 
-	if (get_slice_psize(mm, address) != mmu_huge_psize)
+	/* Verify it is a huge page else bail. */
+	if (!mmu_huge_psizes[mmu_psize])
 		return ERR_PTR(-EINVAL);
 
 	ptep = huge_pte_offset(mm, address);
 	page = pte_page(*ptep);
-	if (page)
-		page += (address % HPAGE_SIZE) / PAGE_SIZE;
+	if (page) {
+		unsigned int shift = mmu_psize_to_shift(mmu_psize);
+		unsigned long sz = ((1UL) << shift);
+		page += (address % sz) / PAGE_SIZE;
+	}
 
 	return page;
 }
@@ -425,15 +498,16 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 					unsigned long len, unsigned long pgoff,
 					unsigned long flags)
 {
-	return slice_get_unmapped_area(addr, len, flags,
-				       mmu_huge_psize, 1, 0);
+	struct hstate *hstate = hstate_file(file);
+	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
+	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
 }
 
 /*
  * Called by asm hashtable.S for doing lazy icache flush
  */
 static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
-						  pte_t pte, int trap)
+					pte_t pte, int trap, unsigned long sz)
 {
 	struct page *page;
 	int i;
@@ -446,7 +520,7 @@ static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
 	/* page is dirty */
 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
 		if (trap == 0x400) {
-			for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
+			for (i = 0; i < (sz / PAGE_SIZE); i++)
 				__flush_dcache_icache(page_address(page+i));
 			set_bit(PG_arch_1, &page->flags);
 		} else {
@@ -466,7 +540,12 @@ int hash_huge_page(struct mm_struct *mm, unsigned long access,
 	long slot;
 	int err = 1;
 	int ssize = user_segment_size(ea);
+	unsigned int mmu_psize;
+	int shift;
+	mmu_psize = get_slice_psize(mm, ea);
 
+	if(!mmu_huge_psizes[mmu_psize])
+		goto out;
 	ptep = huge_pte_offset(mm, ea);
 
 	/* Search the Linux page table for a match with va */
@@ -510,30 +589,32 @@ int hash_huge_page(struct mm_struct *mm, unsigned long access,
 	rflags = 0x2 | (!(new_pte & _PAGE_RW));
  	/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
 	rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
+	shift = mmu_psize_to_shift(mmu_psize);
+	unsigned long sz = ((1UL) << shift);
 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
 		/* No CPU has hugepages but lacks no execute, so we
 		 * don't need to worry about that case */
 		rflags = hash_huge_page_do_lazy_icache(rflags, __pte(old_pte),
-						       trap);
+						       trap, sz);
 
 	/* Check if pte already has an hpte (case 2) */
 	if (unlikely(old_pte & _PAGE_HASHPTE)) {
 		/* There MIGHT be an HPTE for this pte */
 		unsigned long hash, slot;
 
-		hash = hpt_hash(va, HPAGE_SHIFT, ssize);
+		hash = hpt_hash(va, shift, ssize);
 		if (old_pte & _PAGE_F_SECOND)
 			hash = ~hash;
 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
 		slot += (old_pte & _PAGE_F_GIX) >> 12;
 
-		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
+		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize,
 					 ssize, local) == -1)
 			old_pte &= ~_PAGE_HPTEFLAGS;
 	}
 
 	if (likely(!(old_pte & _PAGE_HASHPTE))) {
-		unsigned long hash = hpt_hash(va, HPAGE_SHIFT, ssize);
+		unsigned long hash = hpt_hash(va, shift, ssize);
 		unsigned long hpte_group;
 
 		pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
@@ -552,7 +633,7 @@ repeat:
 
 		/* Insert into the hash table, primary slot */
 		slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
-					  mmu_huge_psize, ssize);
+					  mmu_psize, ssize);
 
 		/* Primary is full, try the secondary */
 		if (unlikely(slot == -1)) {
@@ -560,7 +641,7 @@ repeat:
 				      HPTES_PER_GROUP) & ~0x7UL; 
 			slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
 						  HPTE_V_SECONDARY,
-						  mmu_huge_psize, ssize);
+						  mmu_psize, ssize);
 			if (slot == -1) {
 				if (mftb() & 0x1)
 					hpte_group = ((hash & htab_hash_mask) *
@@ -597,35 +678,34 @@ void set_huge_psize(int psize)
 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
-		/* Return if huge page size is the same as the
-		 * base page size. */
-		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
+		/* Return if huge page size has already been setup or is the
+		 * same as the base page size. */
+		if (mmu_huge_psizes[psize] ||
+		   mmu_psize_defs[psize].shift == PAGE_SHIFT)
 			return;
+		huge_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT);
 
-		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
-		mmu_huge_psize = psize;
-
-		switch (HPAGE_SHIFT) {
+		switch (mmu_psize_defs[psize].shift) {
 		case PAGE_SHIFT_64K:
 		    /* We only allow 64k hpages with 4k base page,
 		     * which was checked above, and always put them
 		     * at the PMD */
-		    hugepte_shift = PMD_SHIFT;
+		    hugepte_shift[psize] = PMD_SHIFT;
 		    break;
 		case PAGE_SHIFT_16M:
 		    /* 16M pages can be at two different levels
 		     * of pagestables based on base page size */
 		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
-			    hugepte_shift = PMD_SHIFT;
+			    hugepte_shift[psize] = PMD_SHIFT;
 		    else /* 4k base page */
-			    hugepte_shift = PUD_SHIFT;
+			    hugepte_shift[psize] = PUD_SHIFT;
 		    break;
 		case PAGE_SHIFT_16G:
 		    /* 16G pages are always at PGD level */
-		    hugepte_shift = PGDIR_SHIFT;
+		    hugepte_shift[psize] = PGDIR_SHIFT;
 		    break;
 		}
-		hugepte_shift -= HPAGE_SHIFT;
+		hugepte_shift[psize] -= mmu_psize_defs[psize].shift;
 	} else
 		HPAGE_SHIFT = 0;
 }
@@ -633,30 +713,15 @@ void set_huge_psize(int psize)
 static int __init hugepage_setup_sz(char *str)
 {
 	unsigned long long size;
-	int mmu_psize = -1;
+	int mmu_psize;
 	int shift;
 
 	size = memparse(str, &str);
 
 	shift = __ffs(size);
-	switch (shift) {
-#ifndef CONFIG_PPC_64K_PAGES
-	case PAGE_SHIFT_64K:
-		mmu_psize = MMU_PAGE_64K;
-		break;
-#endif
-	case PAGE_SHIFT_16M:
-		mmu_psize = MMU_PAGE_16M;
-		break;
-	case PAGE_SHIFT_16G:
-		mmu_psize = MMU_PAGE_16G;
-		break;
-	}
-
-	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
+	mmu_psize = shift_to_mmu_psize(shift);
+	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift)
 		set_huge_psize(mmu_psize);
-		huge_add_hstate(shift - PAGE_SHIFT);
-	}
 	else
 		printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size);
 
@@ -671,16 +736,30 @@ static void zero_ctor(struct kmem_cache *cache, void *addr)
 
 static int __init hugetlbpage_init(void)
 {
+	unsigned int psize;
 	if (!cpu_has_feature(CPU_FTR_16M_PAGE))
 		return -ENODEV;
-
-	huge_pgtable_cache = kmem_cache_create("hugepte_cache",
-					       HUGEPTE_TABLE_SIZE,
-					       HUGEPTE_TABLE_SIZE,
-					       0,
-					       zero_ctor);
-	if (! huge_pgtable_cache)
-		panic("hugetlbpage_init(): could not create hugepte cache\n");
+	/* Add supported huge page sizes.  Need to change HUGE_MAX_HSTATE
+	 * and adjust PTE_NONCACHE_NUM if the number of supported huge page
+	 * sizes changes.
+	 */
+	set_huge_psize(MMU_PAGE_16M);
+	set_huge_psize(MMU_PAGE_64K);
+	set_huge_psize(MMU_PAGE_16G);
+
+	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+		if (mmu_huge_psizes[psize]) {
+			huge_pgtable_cache(psize) = kmem_cache_create(
+						HUGEPTE_CACHE_NAME(psize),
+						HUGEPTE_TABLE_SIZE(psize),
+						HUGEPTE_TABLE_SIZE(psize),
+						0,
+						zero_ctor);
+			if (!huge_pgtable_cache(psize))
+				panic("hugetlbpage_init(): could not create %s"\
+				      "\n", HUGEPTE_CACHE_NAME(psize));
+		}
+	}
 
 	return 0;
 }
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index c0f5cff..55588d5 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -151,10 +151,10 @@ static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
 };
 
 #ifdef CONFIG_HUGETLB_PAGE
-/* Hugepages need one extra cache, initialized in hugetlbpage.c.  We
- * can't put into the tables above, because HPAGE_SHIFT is not compile
- * time constant. */
-struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+1];
+/* Hugepages need an extra cache per hugepagesize, initialized in
+ * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
+ * is not compile time constant. */
+struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
 #else
 struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
 #endif
diff --git a/arch/powerpc/mm/tlb_64.c b/arch/powerpc/mm/tlb_64.c
index e2d867c..8d79e16 100644
--- a/arch/powerpc/mm/tlb_64.c
+++ b/arch/powerpc/mm/tlb_64.c
@@ -150,7 +150,7 @@ void hpte_need_flush(struct mm_struct *mm, unsigned long addr,
 	 */
 	if (huge) {
 #ifdef CONFIG_HUGETLB_PAGE
-		psize = mmu_huge_psize;
+		psize = get_slice_psize(mm, addr);;
 #else
 		BUG();
 		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */
diff --git a/include/asm-powerpc/mmu-hash64.h b/include/asm-powerpc/mmu-hash64.h
index db1276a..63b0fa5 100644
--- a/include/asm-powerpc/mmu-hash64.h
+++ b/include/asm-powerpc/mmu-hash64.h
@@ -192,9 +192,9 @@ extern int mmu_ci_restrictions;
 
 #ifdef CONFIG_HUGETLB_PAGE
 /*
- * The page size index of the huge pages for use by hugetlbfs
+ * The page size indexes of the huge pages for use by hugetlbfs
  */
-extern int mmu_huge_psize;
+extern unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
 
 #endif /* CONFIG_HUGETLB_PAGE */
 
diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h
index 67834ea..bdf453b 100644
--- a/include/asm-powerpc/page_64.h
+++ b/include/asm-powerpc/page_64.h
@@ -90,6 +90,7 @@ extern unsigned int HPAGE_SHIFT;
 #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
+#define HUGE_MAX_HSTATE		3
 
 #endif /* __ASSEMBLY__ */
 
diff --git a/include/asm-powerpc/pgalloc-64.h b/include/asm-powerpc/pgalloc-64.h
index 6898099..812a1d8 100644
--- a/include/asm-powerpc/pgalloc-64.h
+++ b/include/asm-powerpc/pgalloc-64.h
@@ -22,7 +22,7 @@ extern struct kmem_cache *pgtable_cache[];
 #define PUD_CACHE_NUM		1
 #define PMD_CACHE_NUM		1
 #define HUGEPTE_CACHE_NUM	2
-#define PTE_NONCACHE_NUM	3  /* from GFP rather than kmem_cache */
+#define PTE_NONCACHE_NUM	7  /* from GFP rather than kmem_cache */
 
 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 {
@@ -119,7 +119,7 @@ static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
 	__free_page(ptepage);
 }
 
-#define PGF_CACHENUM_MASK	0x3
+#define PGF_CACHENUM_MASK	0x7
 
 typedef struct pgtable_free {
 	unsigned long val;

[PATCH 6/6] powerpc: support multiple huge page sizes

[Jon Tollefson]

Instead of using the variable mmu_huge_psize to keep track of the huge
page size we use an array of MMU_PAGE_* values.  For each supported
huge page size we need to know the hugepte_shift value and have a
pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
functions so that they know which huge page size they should use.

The hugepage sizes 16M and 64K are setup(if available on the
hardware) so that they don't have to be set on the boot cmd line in
order to use them.  The number of 16G pages have to be specified at
boot-time though (e.g. hugepagesz=16G hugepages=5).


Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hash_utils_64.c  |    9 -
 arch/powerpc/mm/hugetlbpage.c    |  267 +++++++++++++++++++++++++--------------
 arch/powerpc/mm/init_64.c        |    8 -
 arch/powerpc/mm/tlb_64.c         |    2 
 include/asm-powerpc/mmu-hash64.h |    4 
 include/asm-powerpc/page_64.h    |    1 
 include/asm-powerpc/pgalloc-64.h |    4 
 7 files changed, 187 insertions(+), 108 deletions(-)


--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -99,7 +99,6 @@ int mmu_kernel_ssize = MMU_SEGSIZE_256M;
 int mmu_highuser_ssize = MMU_SEGSIZE_256M;
 u16 mmu_slb_size = 64;
 #ifdef CONFIG_HUGETLB_PAGE
-int mmu_huge_psize = MMU_PAGE_16M;
 unsigned int HPAGE_SHIFT;
 #endif
 #ifdef CONFIG_PPC_64K_PAGES
@@ -412,15 +411,15 @@ static void __init htab_init_page_sizes(void)
 	/* Reserve 16G huge page memory sections for huge pages */
 	of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL);
 
-/* Init large page size. Currently, we pick 16M or 1M depending
+/* Set default large page size. Currently, we pick 16M or 1M depending
 	 * on what is available
 	 */
 	if (mmu_psize_defs[MMU_PAGE_16M].shift)
-		set_huge_psize(MMU_PAGE_16M);
+		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_16M].shift;
 	/* With 4k/4level pagetables, we can't (for now) cope with a
 	 * huge page size < PMD_SIZE */
 	else if (mmu_psize_defs[MMU_PAGE_1M].shift)
-		set_huge_psize(MMU_PAGE_1M);
+		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_1M].shift;
 #endif /* CONFIG_HUGETLB_PAGE */
 }
 
@@ -819,7 +818,7 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
 
 #ifdef CONFIG_HUGETLB_PAGE
 	/* Handle hugepage regions */
-	if (HPAGE_SHIFT && psize == mmu_huge_psize) {
+	if (HPAGE_SHIFT && mmu_huge_psizes[psize]) {
 		DBG_LOW(" -> huge page !\n");
 		return hash_huge_page(mm, access, ea, vsid, local, trap);
 	}
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 063ec36..61ce875 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -37,15 +37,30 @@
 static unsigned long gpage_freearray[MAX_NUMBER_GPAGES];
 static unsigned nr_gpages;
 
-unsigned int hugepte_shift;
-#define PTRS_PER_HUGEPTE	(1 << hugepte_shift)
-#define HUGEPTE_TABLE_SIZE	(sizeof(pte_t) << hugepte_shift)
+/* Array of valid huge page sizes - non-zero value(hugepte_shift) is
+ * stored for the huge page sizes that are valid.
+ */
+unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
+
+#define hugepte_shift			mmu_huge_psizes
+#define PTRS_PER_HUGEPTE(psize)		(1 << hugepte_shift[psize])
+#define HUGEPTE_TABLE_SIZE(psize)	(sizeof(pte_t) << hugepte_shift[psize])
+
+#define HUGEPD_SHIFT(psize)		(mmu_psize_to_shift(psize) \
+						+ hugepte_shift[psize])
+#define HUGEPD_SIZE(psize)		(1UL << HUGEPD_SHIFT(psize))
+#define HUGEPD_MASK(psize)		(~(HUGEPD_SIZE(psize)-1))
 
-#define HUGEPD_SHIFT		(HPAGE_SHIFT + hugepte_shift)
-#define HUGEPD_SIZE		(1UL << HUGEPD_SHIFT)
-#define HUGEPD_MASK		(~(HUGEPD_SIZE-1))
+/* Subtract one from array size because we don't need a cache for 4K since
+ * is not a huge page size */
+#define huge_pgtable_cache(psize)	(pgtable_cache[HUGEPTE_CACHE_NUM \
+							+ psize-1])
+#define HUGEPTE_CACHE_NAME(psize)	(huge_pgtable_cache_name[psize])
 
-#define huge_pgtable_cache	(pgtable_cache[HUGEPTE_CACHE_NUM])
+static const char *huge_pgtable_cache_name[MMU_PAGE_COUNT] = {
+	"unused_4K", "hugepte_cache_64K", "unused_64K_AP",
+	"hugepte_cache_1M", "hugepte_cache_16M", "hugepte_cache_16G"
+};
 
 /* Flag to mark huge PD pointers.  This means pmd_bad() and pud_bad()
  * will choke on pointers to hugepte tables, which is handy for
@@ -56,24 +71,49 @@ typedef struct { unsigned long pd; } hugepd_t;
 
 #define hugepd_none(hpd)	((hpd).pd == 0)
 
+static inline int shift_to_mmu_psize(unsigned int shift)
+{
+	switch (shift) {
+#ifndef CONFIG_PPC_64K_PAGES
+	case PAGE_SHIFT_64K:
+	    return MMU_PAGE_64K;
+#endif
+	case PAGE_SHIFT_16M:
+	    return MMU_PAGE_16M;
+	case PAGE_SHIFT_16G:
+	    return MMU_PAGE_16G;
+	}
+	return -1;
+}
+
+static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize)
+{
+	if (mmu_psize_defs[mmu_psize].shift)
+		return mmu_psize_defs[mmu_psize].shift;
+	BUG();
+}
+
 static inline pte_t *hugepd_page(hugepd_t hpd)
 {
 	BUG_ON(!(hpd.pd & HUGEPD_OK));
 	return (pte_t *)(hpd.pd & ~HUGEPD_OK);
 }
 
-static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr)
+static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr,
+				    struct hstate *hstate)
 {
-	unsigned long idx = ((addr >> HPAGE_SHIFT) & (PTRS_PER_HUGEPTE-1));
+	unsigned int shift = huge_page_shift(hstate);
+	int psize = shift_to_mmu_psize(shift);
+	unsigned long idx = ((addr >> shift) & (PTRS_PER_HUGEPTE(psize)-1));
 	pte_t *dir = hugepd_page(*hpdp);
 
 	return dir + idx;
 }
 
 static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
-			   unsigned long address)
+			   unsigned long address, unsigned int psize)
 {
-	pte_t *new = kmem_cache_alloc(huge_pgtable_cache,
+	pte_t *new = kmem_cache_alloc(huge_pgtable_cache(psize),
 				      GFP_KERNEL|__GFP_REPEAT);
 
 	if (! new)
@@ -81,7 +121,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 
 	spin_lock(&mm->page_table_lock);
 	if (!hugepd_none(*hpdp))
-		kmem_cache_free(huge_pgtable_cache, new);
+		kmem_cache_free(huge_pgtable_cache(psize), new);
 	else
 		hpdp->pd = (unsigned long)new | HUGEPD_OK;
 	spin_unlock(&mm->page_table_lock);
@@ -90,21 +130,22 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 
 /* Base page size affects how we walk hugetlb page tables */
 #ifdef CONFIG_PPC_64K_PAGES
-#define hpmd_offset(pud, addr)		pmd_offset(pud, addr)
-#define hpmd_alloc(mm, pud, addr)	pmd_alloc(mm, pud, addr)
+#define hpmd_offset(pud, addr, h)	pmd_offset(pud, addr)
+#define hpmd_alloc(mm, pud, addr, h)	pmd_alloc(mm, pud, addr)
 #else
 static inline
-pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
+pmd_t *hpmd_offset(pud_t *pud, unsigned long addr, struct hstate *hstate)
 {
-	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
+	if (huge_page_shift(hstate) == PAGE_SHIFT_64K)
 		return pmd_offset(pud, addr);
 	else
 		return (pmd_t *) pud;
 }
 static inline
-pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
+pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr,
+		  struct hstate *hstate)
 {
-	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
+	if (huge_page_shift(hstate) == PAGE_SHIFT_64K)
 		return pmd_alloc(mm, pud, addr);
 	else
 		return (pmd_t *) pud;
@@ -130,7 +171,7 @@ void add_gpage(unsigned long addr, unsigned long page_size,
 /* Moves the gigantic page addresses from the temporary list to the
   * huge_boot_pages list.
  */
-int alloc_bm_huge_page(struct hstate *h)
+int alloc_bm_huge_page(struct hstate *hstate)
 {
 	struct huge_bm_page *m;
 	if (nr_gpages == 0)
@@ -138,7 +179,7 @@ int alloc_bm_huge_page(struct hstate *h)
 	m = phys_to_virt(gpage_freearray[--nr_gpages]);
 	gpage_freearray[nr_gpages] = 0;
 	list_add(&m->list, &huge_boot_pages);
-	m->hstate = h;
+	m->hstate = hstate;
 	return 1;
 }
 
@@ -150,17 +191,25 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	pud_t *pu;
 	pmd_t *pm;
 
-	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
+	unsigned int psize;
+	unsigned int shift;
+	unsigned long sz;
+	struct hstate *hstate;
+	psize = get_slice_psize(mm, addr);
+	shift = mmu_psize_to_shift(psize);
+	sz = ((1UL) << shift);
+	hstate = size_to_hstate(sz);
 
-	addr &= HPAGE_MASK;
+	addr &= hstate->mask;
 
 	pg = pgd_offset(mm, addr);
 	if (!pgd_none(*pg)) {
 		pu = pud_offset(pg, addr);
 		if (!pud_none(*pu)) {
-			pm = hpmd_offset(pu, addr);
+			pm = hpmd_offset(pu, addr, hstate);
 			if (!pmd_none(*pm))
-				return hugepte_offset((hugepd_t *)pm, addr);
+				return hugepte_offset((hugepd_t *)pm, addr,
+						      hstate);
 		}
 	}
 
@@ -173,16 +222,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz
 	pud_t *pu;
 	pmd_t *pm;
 	hugepd_t *hpdp = NULL;
+	struct hstate *hstate;
+	unsigned int psize;
+	hstate = size_to_hstate(sz);
 
-	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
+	psize = get_slice_psize(mm, addr);
+	BUG_ON(!mmu_huge_psizes[psize]);
 
-	addr &= HPAGE_MASK;
+	addr &= hstate->mask;
 
 	pg = pgd_offset(mm, addr);
 	pu = pud_alloc(mm, pg, addr);
 
 	if (pu) {
-		pm = hpmd_alloc(mm, pu, addr);
+		pm = hpmd_alloc(mm, pu, addr, hstate);
 		if (pm)
 			hpdp = (hugepd_t *)pm;
 	}
@@ -190,10 +243,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz
 	if (! hpdp)
 		return NULL;
 
-	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
+	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize))
 		return NULL;
 
-	return hugepte_offset(hpdp, addr);
+	return hugepte_offset(hpdp, addr, hstate);
 }
 
 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
@@ -201,19 +254,22 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 	return 0;
 }
 
-static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
+static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp,
+			       unsigned int psize)
 {
 	pte_t *hugepte = hugepd_page(*hpdp);
 
 	hpdp->pd = 0;
 	tlb->need_flush = 1;
-	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
+	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte,
+						 HUGEPTE_CACHE_NUM+psize-1,
 						 PGF_CACHENUM_MASK));
 }
 
 static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
 				   unsigned long addr, unsigned long end,
-				   unsigned long floor, unsigned long ceiling)
+				   unsigned long floor, unsigned long ceiling,
+				   unsigned int psize)
 {
 	pmd_t *pmd;
 	unsigned long next;
@@ -225,7 +281,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
 		next = pmd_addr_end(addr, end);
 		if (pmd_none(*pmd))
 			continue;
-		free_hugepte_range(tlb, (hugepd_t *)pmd);
+		free_hugepte_range(tlb, (hugepd_t *)pmd, psize);
 	} while (pmd++, addr = next, addr != end);
 
 	start &= PUD_MASK;
@@ -251,6 +307,9 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 	pud_t *pud;
 	unsigned long next;
 	unsigned long start;
+	unsigned int shift;
+	unsigned int psize = get_slice_psize(tlb->mm, addr);
+	shift = mmu_psize_to_shift(psize);
 
 	start = addr;
 	pud = pud_offset(pgd, addr);
@@ -259,16 +318,18 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 #ifdef CONFIG_PPC_64K_PAGES
 		if (pud_none_or_clear_bad(pud))
 			continue;
-		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
+		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling,
+				       psize);
 #else
-		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
+		if (shift == PAGE_SHIFT_64K) {
 			if (pud_none_or_clear_bad(pud))
 				continue;
-			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
+			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
+					       ceiling, psize);
 		} else {
 			if (pud_none(*pud))
 				continue;
-			free_hugepte_range(tlb, (hugepd_t *)pud);
+			free_hugepte_range(tlb, (hugepd_t *)pud, psize);
 		}
 #endif
 	} while (pud++, addr = next, addr != end);
@@ -336,27 +397,29 @@ void hugetlb_free_pgd_range(struct mmu_gather **tlb,
 	 * now has no other vmas using it, so can be freed, we don't
 	 * bother to round floor or end up - the tests don't need that.
 	 */
+	unsigned int psize = get_slice_psize((*tlb)->mm, addr);
 
-	addr &= HUGEPD_MASK;
+	addr &= HUGEPD_MASK(psize);
 	if (addr < floor) {
-		addr += HUGEPD_SIZE;
+		addr += HUGEPD_SIZE(psize);
 		if (!addr)
 			return;
 	}
 	if (ceiling) {
-		ceiling &= HUGEPD_MASK;
+		ceiling &= HUGEPD_MASK(psize);
 		if (!ceiling)
 			return;
 	}
 	if (end - 1 > ceiling - 1)
-		end -= HUGEPD_SIZE;
+		end -= HUGEPD_SIZE(psize);
 	if (addr > end - 1)
 		return;
 
 	start = addr;
 	pgd = pgd_offset((*tlb)->mm, addr);
 	do {
-		BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
+		psize = get_slice_psize((*tlb)->mm, addr);
+		BUG_ON(!mmu_huge_psizes[psize]);
 		next = pgd_addr_end(addr, end);
 		if (pgd_none_or_clear_bad(pgd))
 			continue;
@@ -373,7 +436,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 		 * necessary anymore if we make hpte_need_flush() get the
 		 * page size from the slices
 		 */
-		pte_update(mm, addr & HPAGE_MASK, ptep, ~0UL, 1);
+		unsigned int psize = get_slice_psize(mm, addr);
+		unsigned int shift = mmu_psize_to_shift(psize);
+		unsigned long sz;
+		sz = ((1UL) << shift);
+		struct hstate *hstate = size_to_hstate(sz);
+		pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1);
 	}
 	*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
 }
@@ -390,14 +458,19 @@ follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
 {
 	pte_t *ptep;
 	struct page *page;
+	unsigned int mmu_psize = get_slice_psize(mm, address);
 
-	if (get_slice_psize(mm, address) != mmu_huge_psize)
+	/* Verify it is a huge page else bail. */
+	if (!mmu_huge_psizes[mmu_psize])
 		return ERR_PTR(-EINVAL);
 
 	ptep = huge_pte_offset(mm, address);
 	page = pte_page(*ptep);
-	if (page)
-		page += (address % HPAGE_SIZE) / PAGE_SIZE;
+	if (page) {
+		unsigned int shift = mmu_psize_to_shift(mmu_psize);
+		unsigned long sz = ((1UL) << shift);
+		page += (address % sz) / PAGE_SIZE;
+	}
 
 	return page;
 }
@@ -425,15 +498,16 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 					unsigned long len, unsigned long pgoff,
 					unsigned long flags)
 {
-	return slice_get_unmapped_area(addr, len, flags,
-				       mmu_huge_psize, 1, 0);
+	struct hstate *hstate = hstate_file(file);
+	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
+	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
 }
 
 /*
  * Called by asm hashtable.S for doing lazy icache flush
  */
 static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
-						  pte_t pte, int trap)
+					pte_t pte, int trap, unsigned long sz)
 {
 	struct page *page;
 	int i;
@@ -446,7 +520,7 @@ static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
 	/* page is dirty */
 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
 		if (trap == 0x400) {
-			for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
+			for (i = 0; i < (sz / PAGE_SIZE); i++)
 				__flush_dcache_icache(page_address(page+i));
 			set_bit(PG_arch_1, &page->flags);
 		} else {
@@ -466,7 +540,12 @@ int hash_huge_page(struct mm_struct *mm, unsigned long access,
 	long slot;
 	int err = 1;
 	int ssize = user_segment_size(ea);
+	unsigned int mmu_psize;
+	int shift;
+	mmu_psize = get_slice_psize(mm, ea);
 
+	if(!mmu_huge_psizes[mmu_psize])
+		goto out;
 	ptep = huge_pte_offset(mm, ea);
 
 	/* Search the Linux page table for a match with va */
@@ -510,30 +589,32 @@ int hash_huge_page(struct mm_struct *mm, unsigned long access,
 	rflags = 0x2 | (!(new_pte & _PAGE_RW));
  	/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
 	rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
+	shift = mmu_psize_to_shift(mmu_psize);
+	unsigned long sz = ((1UL) << shift);
 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
 		/* No CPU has hugepages but lacks no execute, so we
 		 * don't need to worry about that case */
 		rflags = hash_huge_page_do_lazy_icache(rflags, __pte(old_pte),
-						       trap);
+						       trap, sz);
 
 	/* Check if pte already has an hpte (case 2) */
 	if (unlikely(old_pte & _PAGE_HASHPTE)) {
 		/* There MIGHT be an HPTE for this pte */
 		unsigned long hash, slot;
 
-		hash = hpt_hash(va, HPAGE_SHIFT, ssize);
+		hash = hpt_hash(va, shift, ssize);
 		if (old_pte & _PAGE_F_SECOND)
 			hash = ~hash;
 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
 		slot += (old_pte & _PAGE_F_GIX) >> 12;
 
-		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
+		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize,
 					 ssize, local) == -1)
 			old_pte &= ~_PAGE_HPTEFLAGS;
 	}
 
 	if (likely(!(old_pte & _PAGE_HASHPTE))) {
-		unsigned long hash = hpt_hash(va, HPAGE_SHIFT, ssize);
+		unsigned long hash = hpt_hash(va, shift, ssize);
 		unsigned long hpte_group;
 
 		pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
@@ -552,7 +633,7 @@ repeat:
 
 		/* Insert into the hash table, primary slot */
 		slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
-					  mmu_huge_psize, ssize);
+					  mmu_psize, ssize);
 
 		/* Primary is full, try the secondary */
 		if (unlikely(slot == -1)) {
@@ -560,7 +641,7 @@ repeat:
 				      HPTES_PER_GROUP) & ~0x7UL; 
 			slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
 						  HPTE_V_SECONDARY,
-						  mmu_huge_psize, ssize);
+						  mmu_psize, ssize);
 			if (slot == -1) {
 				if (mftb() & 0x1)
 					hpte_group = ((hash & htab_hash_mask) *
@@ -597,35 +678,34 @@ void set_huge_psize(int psize)
 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
-		/* Return if huge page size is the same as the
-		 * base page size. */
-		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
+		/* Return if huge page size has already been setup or is the
+		 * same as the base page size. */
+		if (mmu_huge_psizes[psize] ||
+		   mmu_psize_defs[psize].shift == PAGE_SHIFT)
 			return;
+		huge_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT);
 
-		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
-		mmu_huge_psize = psize;
-
-		switch (HPAGE_SHIFT) {
+		switch (mmu_psize_defs[psize].shift) {
 		case PAGE_SHIFT_64K:
 		    /* We only allow 64k hpages with 4k base page,
 		     * which was checked above, and always put them
 		     * at the PMD */
-		    hugepte_shift = PMD_SHIFT;
+		    hugepte_shift[psize] = PMD_SHIFT;
 		    break;
 		case PAGE_SHIFT_16M:
 		    /* 16M pages can be at two different levels
 		     * of pagestables based on base page size */
 		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
-			    hugepte_shift = PMD_SHIFT;
+			    hugepte_shift[psize] = PMD_SHIFT;
 		    else /* 4k base page */
-			    hugepte_shift = PUD_SHIFT;
+			    hugepte_shift[psize] = PUD_SHIFT;
 		    break;
 		case PAGE_SHIFT_16G:
 		    /* 16G pages are always at PGD level */
-		    hugepte_shift = PGDIR_SHIFT;
+		    hugepte_shift[psize] = PGDIR_SHIFT;
 		    break;
 		}
-		hugepte_shift -= HPAGE_SHIFT;
+		hugepte_shift[psize] -= mmu_psize_defs[psize].shift;
 	} else
 		HPAGE_SHIFT = 0;
 }
@@ -633,30 +713,15 @@ void set_huge_psize(int psize)
 static int __init hugepage_setup_sz(char *str)
 {
 	unsigned long long size;
-	int mmu_psize = -1;
+	int mmu_psize;
 	int shift;
 
 	size = memparse(str, &str);
 
 	shift = __ffs(size);
-	switch (shift) {
-#ifndef CONFIG_PPC_64K_PAGES
-	case PAGE_SHIFT_64K:
-		mmu_psize = MMU_PAGE_64K;
-		break;
-#endif
-	case PAGE_SHIFT_16M:
-		mmu_psize = MMU_PAGE_16M;
-		break;
-	case PAGE_SHIFT_16G:
-		mmu_psize = MMU_PAGE_16G;
-		break;
-	}
-
-	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
+	mmu_psize = shift_to_mmu_psize(shift);
+	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift)
 		set_huge_psize(mmu_psize);
-		huge_add_hstate(shift - PAGE_SHIFT);
-	}
 	else
 		printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size);
 
@@ -671,16 +736,30 @@ static void zero_ctor(struct kmem_cache *cache, void *addr)
 
 static int __init hugetlbpage_init(void)
 {
+	unsigned int psize;
 	if (!cpu_has_feature(CPU_FTR_16M_PAGE))
 		return -ENODEV;
-
-	huge_pgtable_cache = kmem_cache_create("hugepte_cache",
-					       HUGEPTE_TABLE_SIZE,
-					       HUGEPTE_TABLE_SIZE,
-					       0,
-					       zero_ctor);
-	if (! huge_pgtable_cache)
-		panic("hugetlbpage_init(): could not create hugepte cache\n");
+	/* Add supported huge page sizes.  Need to change HUGE_MAX_HSTATE
+	 * and adjust PTE_NONCACHE_NUM if the number of supported huge page
+	 * sizes changes.
+	 */
+	set_huge_psize(MMU_PAGE_16M);
+	set_huge_psize(MMU_PAGE_64K);
+	set_huge_psize(MMU_PAGE_16G);
+
+	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+		if (mmu_huge_psizes[psize]) {
+			huge_pgtable_cache(psize) = kmem_cache_create(
+						HUGEPTE_CACHE_NAME(psize),
+						HUGEPTE_TABLE_SIZE(psize),
+						HUGEPTE_TABLE_SIZE(psize),
+						0,
+						zero_ctor);
+			if (!huge_pgtable_cache(psize))
+				panic("hugetlbpage_init(): could not create %s"\
+				      "\n", HUGEPTE_CACHE_NAME(psize));
+		}
+	}
 
 	return 0;
 }
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index c0f5cff..55588d5 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -151,10 +151,10 @@ static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
 };
 
 #ifdef CONFIG_HUGETLB_PAGE
-/* Hugepages need one extra cache, initialized in hugetlbpage.c.  We
- * can't put into the tables above, because HPAGE_SHIFT is not compile
- * time constant. */
-struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+1];
+/* Hugepages need an extra cache per hugepagesize, initialized in
+ * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
+ * is not compile time constant. */
+struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
 #else
 struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
 #endif
diff --git a/arch/powerpc/mm/tlb_64.c b/arch/powerpc/mm/tlb_64.c
index e2d867c..8d79e16 100644
--- a/arch/powerpc/mm/tlb_64.c
+++ b/arch/powerpc/mm/tlb_64.c
@@ -150,7 +150,7 @@ void hpte_need_flush(struct mm_struct *mm, unsigned long addr,
 	 */
 	if (huge) {
 #ifdef CONFIG_HUGETLB_PAGE
-		psize = mmu_huge_psize;
+		psize = get_slice_psize(mm, addr);;
 #else
 		BUG();
 		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */
diff --git a/include/asm-powerpc/mmu-hash64.h b/include/asm-powerpc/mmu-hash64.h
index db1276a..63b0fa5 100644
--- a/include/asm-powerpc/mmu-hash64.h
+++ b/include/asm-powerpc/mmu-hash64.h
@@ -192,9 +192,9 @@ extern int mmu_ci_restrictions;
 
 #ifdef CONFIG_HUGETLB_PAGE
 /*
- * The page size index of the huge pages for use by hugetlbfs
+ * The page size indexes of the huge pages for use by hugetlbfs
  */
-extern int mmu_huge_psize;
+extern unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
 
 #endif /* CONFIG_HUGETLB_PAGE */
 
diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h
index 67834ea..bdf453b 100644
--- a/include/asm-powerpc/page_64.h
+++ b/include/asm-powerpc/page_64.h
@@ -90,6 +90,7 @@ extern unsigned int HPAGE_SHIFT;
 #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
+#define HUGE_MAX_HSTATE		3
 
 #endif /* __ASSEMBLY__ */
 
diff --git a/include/asm-powerpc/pgalloc-64.h b/include/asm-powerpc/pgalloc-64.h
index 6898099..812a1d8 100644
--- a/include/asm-powerpc/pgalloc-64.h
+++ b/include/asm-powerpc/pgalloc-64.h
@@ -22,7 +22,7 @@ extern struct kmem_cache *pgtable_cache[];
 #define PUD_CACHE_NUM		1
 #define PMD_CACHE_NUM		1
 #define HUGEPTE_CACHE_NUM	2
-#define PTE_NONCACHE_NUM	3  /* from GFP rather than kmem_cache */
+#define PTE_NONCACHE_NUM	7  /* from GFP rather than kmem_cache */
 
 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 {
@@ -119,7 +119,7 @@ static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
 	__free_page(ptepage);
 }
 
-#define PGF_CACHENUM_MASK	0x3
+#define PGF_CACHENUM_MASK	0x7
 
 typedef struct pgtable_free {
 	unsigned long val;


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[PATCH 6/6] powerpc: support multiple huge page sizes

[Jon Tollefson]

Instead of using the variable mmu_huge_psize to keep track of the huge
page size we use an array of MMU_PAGE_* values.  For each supported
huge page size we need to know the hugepte_shift value and have a
pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
functions so that they know which huge page size they should use.

The hugepage sizes 16M and 64K are setup(if available on the
hardware) so that they don't have to be set on the boot cmd line in
order to use them.  The number of 16G pages have to be specified at
boot-time though (e.g. hugepagesz=16G hugepages=5).


Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
---

 arch/powerpc/mm/hash_utils_64.c  |    9 -
 arch/powerpc/mm/hugetlbpage.c    |  267 +++++++++++++++++++++++++--------------
 arch/powerpc/mm/init_64.c        |    8 -
 arch/powerpc/mm/tlb_64.c         |    2 
 include/asm-powerpc/mmu-hash64.h |    4 
 include/asm-powerpc/page_64.h    |    1 
 include/asm-powerpc/pgalloc-64.h |    4 
 7 files changed, 187 insertions(+), 108 deletions(-)


--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -99,7 +99,6 @@ int mmu_kernel_ssize = MMU_SEGSIZE_256M;
 int mmu_highuser_ssize = MMU_SEGSIZE_256M;
 u16 mmu_slb_size = 64;
 #ifdef CONFIG_HUGETLB_PAGE
-int mmu_huge_psize = MMU_PAGE_16M;
 unsigned int HPAGE_SHIFT;
 #endif
 #ifdef CONFIG_PPC_64K_PAGES
@@ -412,15 +411,15 @@ static void __init htab_init_page_sizes(void)
 	/* Reserve 16G huge page memory sections for huge pages */
 	of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL);
 
-/* Init large page size. Currently, we pick 16M or 1M depending
+/* Set default large page size. Currently, we pick 16M or 1M depending
 	 * on what is available
 	 */
 	if (mmu_psize_defs[MMU_PAGE_16M].shift)
-		set_huge_psize(MMU_PAGE_16M);
+		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_16M].shift;
 	/* With 4k/4level pagetables, we can't (for now) cope with a
 	 * huge page size < PMD_SIZE */
 	else if (mmu_psize_defs[MMU_PAGE_1M].shift)
-		set_huge_psize(MMU_PAGE_1M);
+		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_1M].shift;
 #endif /* CONFIG_HUGETLB_PAGE */
 }
 
@@ -819,7 +818,7 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
 
 #ifdef CONFIG_HUGETLB_PAGE
 	/* Handle hugepage regions */
-	if (HPAGE_SHIFT && psize == mmu_huge_psize) {
+	if (HPAGE_SHIFT && mmu_huge_psizes[psize]) {
 		DBG_LOW(" -> huge page !\n");
 		return hash_huge_page(mm, access, ea, vsid, local, trap);
 	}
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 063ec36..61ce875 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -37,15 +37,30 @@
 static unsigned long gpage_freearray[MAX_NUMBER_GPAGES];
 static unsigned nr_gpages;
 
-unsigned int hugepte_shift;
-#define PTRS_PER_HUGEPTE	(1 << hugepte_shift)
-#define HUGEPTE_TABLE_SIZE	(sizeof(pte_t) << hugepte_shift)
+/* Array of valid huge page sizes - non-zero value(hugepte_shift) is
+ * stored for the huge page sizes that are valid.
+ */
+unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
+
+#define hugepte_shift			mmu_huge_psizes
+#define PTRS_PER_HUGEPTE(psize)		(1 << hugepte_shift[psize])
+#define HUGEPTE_TABLE_SIZE(psize)	(sizeof(pte_t) << hugepte_shift[psize])
+
+#define HUGEPD_SHIFT(psize)		(mmu_psize_to_shift(psize) \
+						+ hugepte_shift[psize])
+#define HUGEPD_SIZE(psize)		(1UL << HUGEPD_SHIFT(psize))
+#define HUGEPD_MASK(psize)		(~(HUGEPD_SIZE(psize)-1))
 
-#define HUGEPD_SHIFT		(HPAGE_SHIFT + hugepte_shift)
-#define HUGEPD_SIZE		(1UL << HUGEPD_SHIFT)
-#define HUGEPD_MASK		(~(HUGEPD_SIZE-1))
+/* Subtract one from array size because we don't need a cache for 4K since
+ * is not a huge page size */
+#define huge_pgtable_cache(psize)	(pgtable_cache[HUGEPTE_CACHE_NUM \
+							+ psize-1])
+#define HUGEPTE_CACHE_NAME(psize)	(huge_pgtable_cache_name[psize])
 
-#define huge_pgtable_cache	(pgtable_cache[HUGEPTE_CACHE_NUM])
+static const char *huge_pgtable_cache_name[MMU_PAGE_COUNT] = {
+	"unused_4K", "hugepte_cache_64K", "unused_64K_AP",
+	"hugepte_cache_1M", "hugepte_cache_16M", "hugepte_cache_16G"
+};
 
 /* Flag to mark huge PD pointers.  This means pmd_bad() and pud_bad()
  * will choke on pointers to hugepte tables, which is handy for
@@ -56,24 +71,49 @@ typedef struct { unsigned long pd; } hugepd_t;
 
 #define hugepd_none(hpd)	((hpd).pd == 0)
 
+static inline int shift_to_mmu_psize(unsigned int shift)
+{
+	switch (shift) {
+#ifndef CONFIG_PPC_64K_PAGES
+	case PAGE_SHIFT_64K:
+	    return MMU_PAGE_64K;
+#endif
+	case PAGE_SHIFT_16M:
+	    return MMU_PAGE_16M;
+	case PAGE_SHIFT_16G:
+	    return MMU_PAGE_16G;
+	}
+	return -1;
+}
+
+static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize)
+{
+	if (mmu_psize_defs[mmu_psize].shift)
+		return mmu_psize_defs[mmu_psize].shift;
+	BUG();
+}
+
 static inline pte_t *hugepd_page(hugepd_t hpd)
 {
 	BUG_ON(!(hpd.pd & HUGEPD_OK));
 	return (pte_t *)(hpd.pd & ~HUGEPD_OK);
 }
 
-static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr)
+static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr,
+				    struct hstate *hstate)
 {
-	unsigned long idx = ((addr >> HPAGE_SHIFT) & (PTRS_PER_HUGEPTE-1));
+	unsigned int shift = huge_page_shift(hstate);
+	int psize = shift_to_mmu_psize(shift);
+	unsigned long idx = ((addr >> shift) & (PTRS_PER_HUGEPTE(psize)-1));
 	pte_t *dir = hugepd_page(*hpdp);
 
 	return dir + idx;
 }
 
 static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
-			   unsigned long address)
+			   unsigned long address, unsigned int psize)
 {
-	pte_t *new = kmem_cache_alloc(huge_pgtable_cache,
+	pte_t *new = kmem_cache_alloc(huge_pgtable_cache(psize),
 				      GFP_KERNEL|__GFP_REPEAT);
 
 	if (! new)
@@ -81,7 +121,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 
 	spin_lock(&mm->page_table_lock);
 	if (!hugepd_none(*hpdp))
-		kmem_cache_free(huge_pgtable_cache, new);
+		kmem_cache_free(huge_pgtable_cache(psize), new);
 	else
 		hpdp->pd = (unsigned long)new | HUGEPD_OK;
 	spin_unlock(&mm->page_table_lock);
@@ -90,21 +130,22 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 
 /* Base page size affects how we walk hugetlb page tables */
 #ifdef CONFIG_PPC_64K_PAGES
-#define hpmd_offset(pud, addr)		pmd_offset(pud, addr)
-#define hpmd_alloc(mm, pud, addr)	pmd_alloc(mm, pud, addr)
+#define hpmd_offset(pud, addr, h)	pmd_offset(pud, addr)
+#define hpmd_alloc(mm, pud, addr, h)	pmd_alloc(mm, pud, addr)
 #else
 static inline
-pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
+pmd_t *hpmd_offset(pud_t *pud, unsigned long addr, struct hstate *hstate)
 {
-	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
+	if (huge_page_shift(hstate) == PAGE_SHIFT_64K)
 		return pmd_offset(pud, addr);
 	else
 		return (pmd_t *) pud;
 }
 static inline
-pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
+pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr,
+		  struct hstate *hstate)
 {
-	if (HPAGE_SHIFT == PAGE_SHIFT_64K)
+	if (huge_page_shift(hstate) == PAGE_SHIFT_64K)
 		return pmd_alloc(mm, pud, addr);
 	else
 		return (pmd_t *) pud;
@@ -130,7 +171,7 @@ void add_gpage(unsigned long addr, unsigned long page_size,
 /* Moves the gigantic page addresses from the temporary list to the
   * huge_boot_pages list.
  */
-int alloc_bm_huge_page(struct hstate *h)
+int alloc_bm_huge_page(struct hstate *hstate)
 {
 	struct huge_bm_page *m;
 	if (nr_gpages == 0)
@@ -138,7 +179,7 @@ int alloc_bm_huge_page(struct hstate *h)
 	m = phys_to_virt(gpage_freearray[--nr_gpages]);
 	gpage_freearray[nr_gpages] = 0;
 	list_add(&m->list, &huge_boot_pages);
-	m->hstate = h;
+	m->hstate = hstate;
 	return 1;
 }
 
@@ -150,17 +191,25 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	pud_t *pu;
 	pmd_t *pm;
 
-	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
+	unsigned int psize;
+	unsigned int shift;
+	unsigned long sz;
+	struct hstate *hstate;
+	psize = get_slice_psize(mm, addr);
+	shift = mmu_psize_to_shift(psize);
+	sz = ((1UL) << shift);
+	hstate = size_to_hstate(sz);
 
-	addr &= HPAGE_MASK;
+	addr &= hstate->mask;
 
 	pg = pgd_offset(mm, addr);
 	if (!pgd_none(*pg)) {
 		pu = pud_offset(pg, addr);
 		if (!pud_none(*pu)) {
-			pm = hpmd_offset(pu, addr);
+			pm = hpmd_offset(pu, addr, hstate);
 			if (!pmd_none(*pm))
-				return hugepte_offset((hugepd_t *)pm, addr);
+				return hugepte_offset((hugepd_t *)pm, addr,
+						      hstate);
 		}
 	}
 
@@ -173,16 +222,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz
 	pud_t *pu;
 	pmd_t *pm;
 	hugepd_t *hpdp = NULL;
+	struct hstate *hstate;
+	unsigned int psize;
+	hstate = size_to_hstate(sz);
 
-	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
+	psize = get_slice_psize(mm, addr);
+	BUG_ON(!mmu_huge_psizes[psize]);
 
-	addr &= HPAGE_MASK;
+	addr &= hstate->mask;
 
 	pg = pgd_offset(mm, addr);
 	pu = pud_alloc(mm, pg, addr);
 
 	if (pu) {
-		pm = hpmd_alloc(mm, pu, addr);
+		pm = hpmd_alloc(mm, pu, addr, hstate);
 		if (pm)
 			hpdp = (hugepd_t *)pm;
 	}
@@ -190,10 +243,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz
 	if (! hpdp)
 		return NULL;
 
-	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
+	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize))
 		return NULL;
 
-	return hugepte_offset(hpdp, addr);
+	return hugepte_offset(hpdp, addr, hstate);
 }
 
 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
@@ -201,19 +254,22 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 	return 0;
 }
 
-static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
+static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp,
+			       unsigned int psize)
 {
 	pte_t *hugepte = hugepd_page(*hpdp);
 
 	hpdp->pd = 0;
 	tlb->need_flush = 1;
-	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
+	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte,
+						 HUGEPTE_CACHE_NUM+psize-1,
 						 PGF_CACHENUM_MASK));
 }
 
 static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
 				   unsigned long addr, unsigned long end,
-				   unsigned long floor, unsigned long ceiling)
+				   unsigned long floor, unsigned long ceiling,
+				   unsigned int psize)
 {
 	pmd_t *pmd;
 	unsigned long next;
@@ -225,7 +281,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
 		next = pmd_addr_end(addr, end);
 		if (pmd_none(*pmd))
 			continue;
-		free_hugepte_range(tlb, (hugepd_t *)pmd);
+		free_hugepte_range(tlb, (hugepd_t *)pmd, psize);
 	} while (pmd++, addr = next, addr != end);
 
 	start &= PUD_MASK;
@@ -251,6 +307,9 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 	pud_t *pud;
 	unsigned long next;
 	unsigned long start;
+	unsigned int shift;
+	unsigned int psize = get_slice_psize(tlb->mm, addr);
+	shift = mmu_psize_to_shift(psize);
 
 	start = addr;
 	pud = pud_offset(pgd, addr);
@@ -259,16 +318,18 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 #ifdef CONFIG_PPC_64K_PAGES
 		if (pud_none_or_clear_bad(pud))
 			continue;
-		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
+		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling,
+				       psize);
 #else
-		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
+		if (shift == PAGE_SHIFT_64K) {
 			if (pud_none_or_clear_bad(pud))
 				continue;
-			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
+			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
+					       ceiling, psize);
 		} else {
 			if (pud_none(*pud))
 				continue;
-			free_hugepte_range(tlb, (hugepd_t *)pud);
+			free_hugepte_range(tlb, (hugepd_t *)pud, psize);
 		}
 #endif
 	} while (pud++, addr = next, addr != end);
@@ -336,27 +397,29 @@ void hugetlb_free_pgd_range(struct mmu_gather **tlb,
 	 * now has no other vmas using it, so can be freed, we don't
 	 * bother to round floor or end up - the tests don't need that.
 	 */
+	unsigned int psize = get_slice_psize((*tlb)->mm, addr);
 
-	addr &= HUGEPD_MASK;
+	addr &= HUGEPD_MASK(psize);
 	if (addr < floor) {
-		addr += HUGEPD_SIZE;
+		addr += HUGEPD_SIZE(psize);
 		if (!addr)
 			return;
 	}
 	if (ceiling) {
-		ceiling &= HUGEPD_MASK;
+		ceiling &= HUGEPD_MASK(psize);
 		if (!ceiling)
 			return;
 	}
 	if (end - 1 > ceiling - 1)
-		end -= HUGEPD_SIZE;
+		end -= HUGEPD_SIZE(psize);
 	if (addr > end - 1)
 		return;
 
 	start = addr;
 	pgd = pgd_offset((*tlb)->mm, addr);
 	do {
-		BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
+		psize = get_slice_psize((*tlb)->mm, addr);
+		BUG_ON(!mmu_huge_psizes[psize]);
 		next = pgd_addr_end(addr, end);
 		if (pgd_none_or_clear_bad(pgd))
 			continue;
@@ -373,7 +436,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 		 * necessary anymore if we make hpte_need_flush() get the
 		 * page size from the slices
 		 */
-		pte_update(mm, addr & HPAGE_MASK, ptep, ~0UL, 1);
+		unsigned int psize = get_slice_psize(mm, addr);
+		unsigned int shift = mmu_psize_to_shift(psize);
+		unsigned long sz;
+		sz = ((1UL) << shift);
+		struct hstate *hstate = size_to_hstate(sz);
+		pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1);
 	}
 	*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
 }
@@ -390,14 +458,19 @@ follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
 {
 	pte_t *ptep;
 	struct page *page;
+	unsigned int mmu_psize = get_slice_psize(mm, address);
 
-	if (get_slice_psize(mm, address) != mmu_huge_psize)
+	/* Verify it is a huge page else bail. */
+	if (!mmu_huge_psizes[mmu_psize])
 		return ERR_PTR(-EINVAL);
 
 	ptep = huge_pte_offset(mm, address);
 	page = pte_page(*ptep);
-	if (page)
-		page += (address % HPAGE_SIZE) / PAGE_SIZE;
+	if (page) {
+		unsigned int shift = mmu_psize_to_shift(mmu_psize);
+		unsigned long sz = ((1UL) << shift);
+		page += (address % sz) / PAGE_SIZE;
+	}
 
 	return page;
 }
@@ -425,15 +498,16 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 					unsigned long len, unsigned long pgoff,
 					unsigned long flags)
 {
-	return slice_get_unmapped_area(addr, len, flags,
-				       mmu_huge_psize, 1, 0);
+	struct hstate *hstate = hstate_file(file);
+	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
+	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
 }
 
 /*
  * Called by asm hashtable.S for doing lazy icache flush
  */
 static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
-						  pte_t pte, int trap)
+					pte_t pte, int trap, unsigned long sz)
 {
 	struct page *page;
 	int i;
@@ -446,7 +520,7 @@ static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
 	/* page is dirty */
 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
 		if (trap == 0x400) {
-			for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
+			for (i = 0; i < (sz / PAGE_SIZE); i++)
 				__flush_dcache_icache(page_address(page+i));
 			set_bit(PG_arch_1, &page->flags);
 		} else {
@@ -466,7 +540,12 @@ int hash_huge_page(struct mm_struct *mm, unsigned long access,
 	long slot;
 	int err = 1;
 	int ssize = user_segment_size(ea);
+	unsigned int mmu_psize;
+	int shift;
+	mmu_psize = get_slice_psize(mm, ea);
 
+	if(!mmu_huge_psizes[mmu_psize])
+		goto out;
 	ptep = huge_pte_offset(mm, ea);
 
 	/* Search the Linux page table for a match with va */
@@ -510,30 +589,32 @@ int hash_huge_page(struct mm_struct *mm, unsigned long access,
 	rflags = 0x2 | (!(new_pte & _PAGE_RW));
  	/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
 	rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
+	shift = mmu_psize_to_shift(mmu_psize);
+	unsigned long sz = ((1UL) << shift);
 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
 		/* No CPU has hugepages but lacks no execute, so we
 		 * don't need to worry about that case */
 		rflags = hash_huge_page_do_lazy_icache(rflags, __pte(old_pte),
-						       trap);
+						       trap, sz);
 
 	/* Check if pte already has an hpte (case 2) */
 	if (unlikely(old_pte & _PAGE_HASHPTE)) {
 		/* There MIGHT be an HPTE for this pte */
 		unsigned long hash, slot;
 
-		hash = hpt_hash(va, HPAGE_SHIFT, ssize);
+		hash = hpt_hash(va, shift, ssize);
 		if (old_pte & _PAGE_F_SECOND)
 			hash = ~hash;
 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
 		slot += (old_pte & _PAGE_F_GIX) >> 12;
 
-		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
+		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize,
 					 ssize, local) == -1)
 			old_pte &= ~_PAGE_HPTEFLAGS;
 	}
 
 	if (likely(!(old_pte & _PAGE_HASHPTE))) {
-		unsigned long hash = hpt_hash(va, HPAGE_SHIFT, ssize);
+		unsigned long hash = hpt_hash(va, shift, ssize);
 		unsigned long hpte_group;
 
 		pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
@@ -552,7 +633,7 @@ repeat:
 
 		/* Insert into the hash table, primary slot */
 		slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
-					  mmu_huge_psize, ssize);
+					  mmu_psize, ssize);
 
 		/* Primary is full, try the secondary */
 		if (unlikely(slot == -1)) {
@@ -560,7 +641,7 @@ repeat:
 				      HPTES_PER_GROUP) & ~0x7UL; 
 			slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
 						  HPTE_V_SECONDARY,
-						  mmu_huge_psize, ssize);
+						  mmu_psize, ssize);
 			if (slot == -1) {
 				if (mftb() & 0x1)
 					hpte_group = ((hash & htab_hash_mask) *
@@ -597,35 +678,34 @@ void set_huge_psize(int psize)
 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
-		/* Return if huge page size is the same as the
-		 * base page size. */
-		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
+		/* Return if huge page size has already been setup or is the
+		 * same as the base page size. */
+		if (mmu_huge_psizes[psize] ||
+		   mmu_psize_defs[psize].shift == PAGE_SHIFT)
 			return;
+		huge_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT);
 
-		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
-		mmu_huge_psize = psize;
-
-		switch (HPAGE_SHIFT) {
+		switch (mmu_psize_defs[psize].shift) {
 		case PAGE_SHIFT_64K:
 		    /* We only allow 64k hpages with 4k base page,
 		     * which was checked above, and always put them
 		     * at the PMD */
-		    hugepte_shift = PMD_SHIFT;
+		    hugepte_shift[psize] = PMD_SHIFT;
 		    break;
 		case PAGE_SHIFT_16M:
 		    /* 16M pages can be at two different levels
 		     * of pagestables based on base page size */
 		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
-			    hugepte_shift = PMD_SHIFT;
+			    hugepte_shift[psize] = PMD_SHIFT;
 		    else /* 4k base page */
-			    hugepte_shift = PUD_SHIFT;
+			    hugepte_shift[psize] = PUD_SHIFT;
 		    break;
 		case PAGE_SHIFT_16G:
 		    /* 16G pages are always at PGD level */
-		    hugepte_shift = PGDIR_SHIFT;
+		    hugepte_shift[psize] = PGDIR_SHIFT;
 		    break;
 		}
-		hugepte_shift -= HPAGE_SHIFT;
+		hugepte_shift[psize] -= mmu_psize_defs[psize].shift;
 	} else
 		HPAGE_SHIFT = 0;
 }
@@ -633,30 +713,15 @@ void set_huge_psize(int psize)
 static int __init hugepage_setup_sz(char *str)
 {
 	unsigned long long size;
-	int mmu_psize = -1;
+	int mmu_psize;
 	int shift;
 
 	size = memparse(str, &str);
 
 	shift = __ffs(size);
-	switch (shift) {
-#ifndef CONFIG_PPC_64K_PAGES
-	case PAGE_SHIFT_64K:
-		mmu_psize = MMU_PAGE_64K;
-		break;
-#endif
-	case PAGE_SHIFT_16M:
-		mmu_psize = MMU_PAGE_16M;
-		break;
-	case PAGE_SHIFT_16G:
-		mmu_psize = MMU_PAGE_16G;
-		break;
-	}
-
-	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
+	mmu_psize = shift_to_mmu_psize(shift);
+	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift)
 		set_huge_psize(mmu_psize);
-		huge_add_hstate(shift - PAGE_SHIFT);
-	}
 	else
 		printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size);
 
@@ -671,16 +736,30 @@ static void zero_ctor(struct kmem_cache *cache, void *addr)
 
 static int __init hugetlbpage_init(void)
 {
+	unsigned int psize;
 	if (!cpu_has_feature(CPU_FTR_16M_PAGE))
 		return -ENODEV;
-
-	huge_pgtable_cache = kmem_cache_create("hugepte_cache",
-					       HUGEPTE_TABLE_SIZE,
-					       HUGEPTE_TABLE_SIZE,
-					       0,
-					       zero_ctor);
-	if (! huge_pgtable_cache)
-		panic("hugetlbpage_init(): could not create hugepte cache\n");
+	/* Add supported huge page sizes.  Need to change HUGE_MAX_HSTATE
+	 * and adjust PTE_NONCACHE_NUM if the number of supported huge page
+	 * sizes changes.
+	 */
+	set_huge_psize(MMU_PAGE_16M);
+	set_huge_psize(MMU_PAGE_64K);
+	set_huge_psize(MMU_PAGE_16G);
+
+	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+		if (mmu_huge_psizes[psize]) {
+			huge_pgtable_cache(psize) = kmem_cache_create(
+						HUGEPTE_CACHE_NAME(psize),
+						HUGEPTE_TABLE_SIZE(psize),
+						HUGEPTE_TABLE_SIZE(psize),
+						0,
+						zero_ctor);
+			if (!huge_pgtable_cache(psize))
+				panic("hugetlbpage_init(): could not create %s"\
+				      "\n", HUGEPTE_CACHE_NAME(psize));
+		}
+	}
 
 	return 0;
 }
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index c0f5cff..55588d5 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -151,10 +151,10 @@ static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
 };
 
 #ifdef CONFIG_HUGETLB_PAGE
-/* Hugepages need one extra cache, initialized in hugetlbpage.c.  We
- * can't put into the tables above, because HPAGE_SHIFT is not compile
- * time constant. */
-struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+1];
+/* Hugepages need an extra cache per hugepagesize, initialized in
+ * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
+ * is not compile time constant. */
+struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
 #else
 struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
 #endif
diff --git a/arch/powerpc/mm/tlb_64.c b/arch/powerpc/mm/tlb_64.c
index e2d867c..8d79e16 100644
--- a/arch/powerpc/mm/tlb_64.c
+++ b/arch/powerpc/mm/tlb_64.c
@@ -150,7 +150,7 @@ void hpte_need_flush(struct mm_struct *mm, unsigned long addr,
 	 */
 	if (huge) {
 #ifdef CONFIG_HUGETLB_PAGE
-		psize = mmu_huge_psize;
+		psize = get_slice_psize(mm, addr);;
 #else
 		BUG();
 		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */
diff --git a/include/asm-powerpc/mmu-hash64.h b/include/asm-powerpc/mmu-hash64.h
index db1276a..63b0fa5 100644
--- a/include/asm-powerpc/mmu-hash64.h
+++ b/include/asm-powerpc/mmu-hash64.h
@@ -192,9 +192,9 @@ extern int mmu_ci_restrictions;
 
 #ifdef CONFIG_HUGETLB_PAGE
 /*
- * The page size index of the huge pages for use by hugetlbfs
+ * The page size indexes of the huge pages for use by hugetlbfs
  */
-extern int mmu_huge_psize;
+extern unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
 
 #endif /* CONFIG_HUGETLB_PAGE */
 
diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h
index 67834ea..bdf453b 100644
--- a/include/asm-powerpc/page_64.h
+++ b/include/asm-powerpc/page_64.h
@@ -90,6 +90,7 @@ extern unsigned int HPAGE_SHIFT;
 #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
+#define HUGE_MAX_HSTATE		3
 
 #endif /* __ASSEMBLY__ */
 
diff --git a/include/asm-powerpc/pgalloc-64.h b/include/asm-powerpc/pgalloc-64.h
index 6898099..812a1d8 100644
--- a/include/asm-powerpc/pgalloc-64.h
+++ b/include/asm-powerpc/pgalloc-64.h
@@ -22,7 +22,7 @@ extern struct kmem_cache *pgtable_cache[];
 #define PUD_CACHE_NUM		1
 #define PMD_CACHE_NUM		1
 #define HUGEPTE_CACHE_NUM	2
-#define PTE_NONCACHE_NUM	3  /* from GFP rather than kmem_cache */
+#define PTE_NONCACHE_NUM	7  /* from GFP rather than kmem_cache */
 
 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 {
@@ -119,7 +119,7 @@ static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
 	__free_page(ptepage);
 }
 
-#define PGF_CACHENUM_MASK	0x3
+#define PGF_CACHENUM_MASK	0x7
 
 typedef struct pgtable_free {
 	unsigned long val;

Re: [PATCH 6/6] powerpc: support multiple huge page sizes

[Nick Piggin]

On Tue, May 13, 2008 at 12:25:27PM -0500, Jon Tollefson wrote:
> Instead of using the variable mmu_huge_psize to keep track of the huge
> page size we use an array of MMU_PAGE_* values.  For each supported
> huge page size we need to know the hugepte_shift value and have a
> pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
> functions so that they know which huge page size they should use.
> 
> The hugepage sizes 16M and 64K are setup(if available on the
> hardware) so that they don't have to be set on the boot cmd line in
> order to use them.  The number of 16G pages have to be specified at
> boot-time though (e.g. hugepagesz=16G hugepages=5).
> 
> 
> Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
> ---
> 
> @@ -150,17 +191,25 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned 
> long addr)
> 	pud_t *pu;
> 	pmd_t *pm;
> 
> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
> +	unsigned int psize;
> +	unsigned int shift;
> +	unsigned long sz;
> +	struct hstate *hstate;
> +	psize = get_slice_psize(mm, addr);
> +	shift = mmu_psize_to_shift(psize);
> +	sz = ((1UL) << shift);
> +	hstate = size_to_hstate(sz);
> 
> -	addr &= HPAGE_MASK;
> +	addr &= hstate->mask;
> 
> 	pg = pgd_offset(mm, addr);
> 	if (!pgd_none(*pg)) {
> 		pu = pud_offset(pg, addr);
> 		if (!pud_none(*pu)) {
> -			pm = hpmd_offset(pu, addr);
> +			pm = hpmd_offset(pu, addr, hstate);
> 			if (!pmd_none(*pm))
> -				return hugepte_offset((hugepd_t *)pm, addr);
> +				return hugepte_offset((hugepd_t *)pm, addr,
> +						      hstate);
> 		}
> 	}

Hi Jon,

I just noticed in a few places like this, you might be doing more work
than really needed to get the HPAGE_MASK.

For a first-pass conversion, this is the right way to go (just manually
replace hugepage constants with hstate-> equivalents). However in this
case if you already know the page size, you should be able to work out
the shift from there, I think? That way you can avoid the size_to_hstate
call completely.

Anyway, just something to consider.

Thanks,
Nick
> 
> @@ -173,16 +222,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
> long addr, unsigned long sz
> 	pud_t *pu;
> 	pmd_t *pm;
> 	hugepd_t *hpdp = NULL;
> +	struct hstate *hstate;
> +	unsigned int psize;
> +	hstate = size_to_hstate(sz);
> 
> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
> +	psize = get_slice_psize(mm, addr);
> +	BUG_ON(!mmu_huge_psizes[psize]);
> 
> -	addr &= HPAGE_MASK;
> +	addr &= hstate->mask;
> 
> 	pg = pgd_offset(mm, addr);
> 	pu = pud_alloc(mm, pg, addr);
> 
> 	if (pu) {
> -		pm = hpmd_alloc(mm, pu, addr);
> +		pm = hpmd_alloc(mm, pu, addr, hstate);
> 		if (pm)
> 			hpdp = (hugepd_t *)pm;
> 	}
> @@ -190,10 +243,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
> long addr, unsigned long sz
> 	if (! hpdp)
> 		return NULL;
> 
> -	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
> +	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize))
> 		return NULL;
> 
> -	return hugepte_offset(hpdp, addr);
> +	return hugepte_offset(hpdp, addr, hstate);
> }
> 
> int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
> @@ -201,19 +254,22 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned 
> long *addr, pte_t *ptep)
> 	return 0;
> }
> 
> -static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
> +static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp,
> +			       unsigned int psize)
> {
> 	pte_t *hugepte = hugepd_page(*hpdp);
> 
> 	hpdp->pd = 0;
> 	tlb->need_flush = 1;
> -	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
> +	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte,
> +						 HUGEPTE_CACHE_NUM+psize-1,
> 						 PGF_CACHENUM_MASK));
> }
> 
> static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
> 				   unsigned long addr, unsigned long end,
> -				   unsigned long floor, unsigned long 
> ceiling)
> +				   unsigned long floor, unsigned long 
> ceiling,
> +				   unsigned int psize)
> {
> 	pmd_t *pmd;
> 	unsigned long next;
> @@ -225,7 +281,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather 
> *tlb, pud_t *pud,
> 		next = pmd_addr_end(addr, end);
> 		if (pmd_none(*pmd))
> 			continue;
> -		free_hugepte_range(tlb, (hugepd_t *)pmd);
> +		free_hugepte_range(tlb, (hugepd_t *)pmd, psize);
> 	} while (pmd++, addr = next, addr != end);
> 
> 	start &= PUD_MASK;
> @@ -251,6 +307,9 @@ static void hugetlb_free_pud_range(struct mmu_gather 
> *tlb, pgd_t *pgd,
> 	pud_t *pud;
> 	unsigned long next;
> 	unsigned long start;
> +	unsigned int shift;
> +	unsigned int psize = get_slice_psize(tlb->mm, addr);
> +	shift = mmu_psize_to_shift(psize);
> 
> 	start = addr;
> 	pud = pud_offset(pgd, addr);
> @@ -259,16 +318,18 @@ static void hugetlb_free_pud_range(struct mmu_gather 
> *tlb, pgd_t *pgd,
> #ifdef CONFIG_PPC_64K_PAGES
> 		if (pud_none_or_clear_bad(pud))
> 			continue;
> -		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
> +		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling,
> +				       psize);
> #else
> -		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
> +		if (shift == PAGE_SHIFT_64K) {
> 			if (pud_none_or_clear_bad(pud))
> 				continue;
> -			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, 
> ceiling);
> +			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
> +					       ceiling, psize);
> 		} else {
> 			if (pud_none(*pud))
> 				continue;
> -			free_hugepte_range(tlb, (hugepd_t *)pud);
> +			free_hugepte_range(tlb, (hugepd_t *)pud, psize);
> 		}
> #endif
> 	} while (pud++, addr = next, addr != end);
> @@ -336,27 +397,29 @@ void hugetlb_free_pgd_range(struct mmu_gather **tlb,
> 	 * now has no other vmas using it, so can be freed, we don't
> 	 * bother to round floor or end up - the tests don't need that.
> 	 */
> +	unsigned int psize = get_slice_psize((*tlb)->mm, addr);
> 
> -	addr &= HUGEPD_MASK;
> +	addr &= HUGEPD_MASK(psize);
> 	if (addr < floor) {
> -		addr += HUGEPD_SIZE;
> +		addr += HUGEPD_SIZE(psize);
> 		if (!addr)
> 			return;
> 	}
> 	if (ceiling) {
> -		ceiling &= HUGEPD_MASK;
> +		ceiling &= HUGEPD_MASK(psize);
> 		if (!ceiling)
> 			return;
> 	}
> 	if (end - 1 > ceiling - 1)
> -		end -= HUGEPD_SIZE;
> +		end -= HUGEPD_SIZE(psize);
> 	if (addr > end - 1)
> 		return;
> 
> 	start = addr;
> 	pgd = pgd_offset((*tlb)->mm, addr);
> 	do {
> -		BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
> +		psize = get_slice_psize((*tlb)->mm, addr);
> +		BUG_ON(!mmu_huge_psizes[psize]);
> 		next = pgd_addr_end(addr, end);
> 		if (pgd_none_or_clear_bad(pgd))
> 			continue;
> @@ -373,7 +436,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned 
> long addr,
> 		 * necessary anymore if we make hpte_need_flush() get the
> 		 * page size from the slices
> 		 */
> -		pte_update(mm, addr & HPAGE_MASK, ptep, ~0UL, 1);
> +		unsigned int psize = get_slice_psize(mm, addr);
> +		unsigned int shift = mmu_psize_to_shift(psize);
> +		unsigned long sz;
> +		sz = ((1UL) << shift);
> +		struct hstate *hstate = size_to_hstate(sz);
> +		pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1);
> 	}
> 	*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
> }
> @@ -390,14 +458,19 @@ follow_huge_addr(struct mm_struct *mm, unsigned long 
> address, int write)
> {
> 	pte_t *ptep;
> 	struct page *page;
> +	unsigned int mmu_psize = get_slice_psize(mm, address);
> 
> -	if (get_slice_psize(mm, address) != mmu_huge_psize)
> +	/* Verify it is a huge page else bail. */
> +	if (!mmu_huge_psizes[mmu_psize])
> 		return ERR_PTR(-EINVAL);
> 
> 	ptep = huge_pte_offset(mm, address);
> 	page = pte_page(*ptep);
> -	if (page)
> -		page += (address % HPAGE_SIZE) / PAGE_SIZE;
> +	if (page) {
> +		unsigned int shift = mmu_psize_to_shift(mmu_psize);
> +		unsigned long sz = ((1UL) << shift);
> +		page += (address % sz) / PAGE_SIZE;
> +	}
> 
> 	return page;
> }
> @@ -425,15 +498,16 @@ unsigned long hugetlb_get_unmapped_area(struct file 
> *file, unsigned long addr,
> 					unsigned long len, unsigned long 
> 					pgoff,
> 					unsigned long flags)
> {
> -	return slice_get_unmapped_area(addr, len, flags,
> -				       mmu_huge_psize, 1, 0);
> +	struct hstate *hstate = hstate_file(file);
> +	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
> +	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
> }
> 
> /*
>  * Called by asm hashtable.S for doing lazy icache flush
>  */
> static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
> -						  pte_t pte, int trap)
> +					pte_t pte, int trap, unsigned long 
> sz)
> {
> 	struct page *page;
> 	int i;
> @@ -446,7 +520,7 @@ static unsigned int 
> hash_huge_page_do_lazy_icache(unsigned long rflags,
> 	/* page is dirty */
> 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
> 		if (trap == 0x400) {
> -			for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
> +			for (i = 0; i < (sz / PAGE_SIZE); i++)
> 				__flush_dcache_icache(page_address(page+i));
> 			set_bit(PG_arch_1, &page->flags);
> 		} else {
> @@ -466,7 +540,12 @@ int hash_huge_page(struct mm_struct *mm, unsigned long 
> access,
> 	long slot;
> 	int err = 1;
> 	int ssize = user_segment_size(ea);
> +	unsigned int mmu_psize;
> +	int shift;
> +	mmu_psize = get_slice_psize(mm, ea);
> 
> +	if(!mmu_huge_psizes[mmu_psize])
> +		goto out;
> 	ptep = huge_pte_offset(mm, ea);
> 
> 	/* Search the Linux page table for a match with va */
> @@ -510,30 +589,32 @@ int hash_huge_page(struct mm_struct *mm, unsigned 
> long access,
> 	rflags = 0x2 | (!(new_pte & _PAGE_RW));
>  	/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
> 	rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
> +	shift = mmu_psize_to_shift(mmu_psize);
> +	unsigned long sz = ((1UL) << shift);
> 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
> 		/* No CPU has hugepages but lacks no execute, so we
> 		 * don't need to worry about that case */
> 		rflags = hash_huge_page_do_lazy_icache(rflags, 
> 		__pte(old_pte),
> -						       trap);
> +						       trap, sz);
> 
> 	/* Check if pte already has an hpte (case 2) */
> 	if (unlikely(old_pte & _PAGE_HASHPTE)) {
> 		/* There MIGHT be an HPTE for this pte */
> 		unsigned long hash, slot;
> 
> -		hash = hpt_hash(va, HPAGE_SHIFT, ssize);
> +		hash = hpt_hash(va, shift, ssize);
> 		if (old_pte & _PAGE_F_SECOND)
> 			hash = ~hash;
> 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
> 		slot += (old_pte & _PAGE_F_GIX) >> 12;
> 
> -		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
> +		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize,
> 					 ssize, local) == -1)
> 			old_pte &= ~_PAGE_HPTEFLAGS;
> 	}
> 
> 	if (likely(!(old_pte & _PAGE_HASHPTE))) {
> -		unsigned long hash = hpt_hash(va, HPAGE_SHIFT, ssize);
> +		unsigned long hash = hpt_hash(va, shift, ssize);
> 		unsigned long hpte_group;
> 
> 		pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
> @@ -552,7 +633,7 @@ repeat:
> 
> 		/* Insert into the hash table, primary slot */
> 		slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
> -					  mmu_huge_psize, ssize);
> +					  mmu_psize, ssize);
> 
> 		/* Primary is full, try the secondary */
> 		if (unlikely(slot == -1)) {
> @@ -560,7 +641,7 @@ repeat:
> 				      HPTES_PER_GROUP) & ~0x7UL; 
> 			slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
> 						  HPTE_V_SECONDARY,
> -						  mmu_huge_psize, ssize);
> +						  mmu_psize, ssize);
> 			if (slot == -1) {
> 				if (mftb() & 0x1)
> 					hpte_group = ((hash & 
> 					htab_hash_mask) *
> @@ -597,35 +678,34 @@ void set_huge_psize(int psize)
> 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
> -		/* Return if huge page size is the same as the
> -		 * base page size. */
> -		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
> +		/* Return if huge page size has already been setup or is the
> +		 * same as the base page size. */
> +		if (mmu_huge_psizes[psize] ||
> +		   mmu_psize_defs[psize].shift == PAGE_SHIFT)
> 			return;
> +		huge_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT);
> 
> -		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
> -		mmu_huge_psize = psize;
> -
> -		switch (HPAGE_SHIFT) {
> +		switch (mmu_psize_defs[psize].shift) {
> 		case PAGE_SHIFT_64K:
> 		    /* We only allow 64k hpages with 4k base page,
> 		     * which was checked above, and always put them
> 		     * at the PMD */
> -		    hugepte_shift = PMD_SHIFT;
> +		    hugepte_shift[psize] = PMD_SHIFT;
> 		    break;
> 		case PAGE_SHIFT_16M:
> 		    /* 16M pages can be at two different levels
> 		     * of pagestables based on base page size */
> 		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
> -			    hugepte_shift = PMD_SHIFT;
> +			    hugepte_shift[psize] = PMD_SHIFT;
> 		    else /* 4k base page */
> -			    hugepte_shift = PUD_SHIFT;
> +			    hugepte_shift[psize] = PUD_SHIFT;
> 		    break;
> 		case PAGE_SHIFT_16G:
> 		    /* 16G pages are always at PGD level */
> -		    hugepte_shift = PGDIR_SHIFT;
> +		    hugepte_shift[psize] = PGDIR_SHIFT;
> 		    break;
> 		}
> -		hugepte_shift -= HPAGE_SHIFT;
> +		hugepte_shift[psize] -= mmu_psize_defs[psize].shift;
> 	} else
> 		HPAGE_SHIFT = 0;
> }
> @@ -633,30 +713,15 @@ void set_huge_psize(int psize)
> static int __init hugepage_setup_sz(char *str)
> {
> 	unsigned long long size;
> -	int mmu_psize = -1;
> +	int mmu_psize;
> 	int shift;
> 
> 	size = memparse(str, &str);
> 
> 	shift = __ffs(size);
> -	switch (shift) {
> -#ifndef CONFIG_PPC_64K_PAGES
> -	case PAGE_SHIFT_64K:
> -		mmu_psize = MMU_PAGE_64K;
> -		break;
> -#endif
> -	case PAGE_SHIFT_16M:
> -		mmu_psize = MMU_PAGE_16M;
> -		break;
> -	case PAGE_SHIFT_16G:
> -		mmu_psize = MMU_PAGE_16G;
> -		break;
> -	}
> -
> -	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
> +	mmu_psize = shift_to_mmu_psize(shift);
> +	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift)
> 		set_huge_psize(mmu_psize);
> -		huge_add_hstate(shift - PAGE_SHIFT);
> -	}
> 	else
> 		printk(KERN_WARNING "Invalid huge page size 
> 		specified(%llu)\n", size);
> 
> @@ -671,16 +736,30 @@ static void zero_ctor(struct kmem_cache *cache, void 
> *addr)
> 
> static int __init hugetlbpage_init(void)
> {
> +	unsigned int psize;
> 	if (!cpu_has_feature(CPU_FTR_16M_PAGE))
> 		return -ENODEV;
> -
> -	huge_pgtable_cache = kmem_cache_create("hugepte_cache",
> -					       HUGEPTE_TABLE_SIZE,
> -					       HUGEPTE_TABLE_SIZE,
> -					       0,
> -					       zero_ctor);
> -	if (! huge_pgtable_cache)
> -		panic("hugetlbpage_init(): could not create hugepte 
> cache\n");
> +	/* Add supported huge page sizes.  Need to change HUGE_MAX_HSTATE
> +	 * and adjust PTE_NONCACHE_NUM if the number of supported huge page
> +	 * sizes changes.
> +	 */
> +	set_huge_psize(MMU_PAGE_16M);
> +	set_huge_psize(MMU_PAGE_64K);
> +	set_huge_psize(MMU_PAGE_16G);
> +
> +	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
> +		if (mmu_huge_psizes[psize]) {
> +			huge_pgtable_cache(psize) = kmem_cache_create(
> +						HUGEPTE_CACHE_NAME(psize),
> +						HUGEPTE_TABLE_SIZE(psize),
> +						HUGEPTE_TABLE_SIZE(psize),
> +						0,
> +						zero_ctor);
> +			if (!huge_pgtable_cache(psize))
> +				panic("hugetlbpage_init(): could not create 
> %s"\
> +				      "\n", HUGEPTE_CACHE_NAME(psize));
> +		}
> +	}
> 
> 	return 0;
> }
> diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
> index c0f5cff..55588d5 100644
> --- a/arch/powerpc/mm/init_64.c
> +++ b/arch/powerpc/mm/init_64.c
> @@ -151,10 +151,10 @@ static const char 
> *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
> };
> 
> #ifdef CONFIG_HUGETLB_PAGE
> -/* Hugepages need one extra cache, initialized in hugetlbpage.c.  We
> - * can't put into the tables above, because HPAGE_SHIFT is not compile
> - * time constant. */
> -struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+1];
> +/* Hugepages need an extra cache per hugepagesize, initialized in
> + * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
> + * is not compile time constant. */
> +struct kmem_cache 
> *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
> #else
> struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
> #endif
> diff --git a/arch/powerpc/mm/tlb_64.c b/arch/powerpc/mm/tlb_64.c
> index e2d867c..8d79e16 100644
> --- a/arch/powerpc/mm/tlb_64.c
> +++ b/arch/powerpc/mm/tlb_64.c
> @@ -150,7 +150,7 @@ void hpte_need_flush(struct mm_struct *mm, unsigned 
> long addr,
> 	 */
> 	if (huge) {
> #ifdef CONFIG_HUGETLB_PAGE
> -		psize = mmu_huge_psize;
> +		psize = get_slice_psize(mm, addr);;
> #else
> 		BUG();
> 		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */
> diff --git a/include/asm-powerpc/mmu-hash64.h 
> b/include/asm-powerpc/mmu-hash64.h
> index db1276a..63b0fa5 100644
> --- a/include/asm-powerpc/mmu-hash64.h
> +++ b/include/asm-powerpc/mmu-hash64.h
> @@ -192,9 +192,9 @@ extern int mmu_ci_restrictions;
> 
> #ifdef CONFIG_HUGETLB_PAGE
> /*
> - * The page size index of the huge pages for use by hugetlbfs
> + * The page size indexes of the huge pages for use by hugetlbfs
>  */
> -extern int mmu_huge_psize;
> +extern unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
> 
> #endif /* CONFIG_HUGETLB_PAGE */
> 
> diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h
> index 67834ea..bdf453b 100644
> --- a/include/asm-powerpc/page_64.h
> +++ b/include/asm-powerpc/page_64.h
> @@ -90,6 +90,7 @@ extern unsigned int HPAGE_SHIFT;
> #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
> #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
> #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
> +#define HUGE_MAX_HSTATE		3
> 
> #endif /* __ASSEMBLY__ */
> 
> diff --git a/include/asm-powerpc/pgalloc-64.h 
> b/include/asm-powerpc/pgalloc-64.h
> index 6898099..812a1d8 100644
> --- a/include/asm-powerpc/pgalloc-64.h
> +++ b/include/asm-powerpc/pgalloc-64.h
> @@ -22,7 +22,7 @@ extern struct kmem_cache *pgtable_cache[];
> #define PUD_CACHE_NUM		1
> #define PMD_CACHE_NUM		1
> #define HUGEPTE_CACHE_NUM	2
> -#define PTE_NONCACHE_NUM	3  /* from GFP rather than kmem_cache */
> +#define PTE_NONCACHE_NUM	7  /* from GFP rather than kmem_cache */
> 
> static inline pgd_t *pgd_alloc(struct mm_struct *mm)
> {
> @@ -119,7 +119,7 @@ static inline void pte_free(struct mm_struct *mm, 
> pgtable_t ptepage)
> 	__free_page(ptepage);
> }
> 
> -#define PGF_CACHENUM_MASK	0x3
> +#define PGF_CACHENUM_MASK	0x7
> 
> typedef struct pgtable_free {
> 	unsigned long val;
> 

Re: [PATCH 6/6] powerpc: support multiple huge page sizes

[Nick Piggin]

On Tue, May 13, 2008 at 12:25:27PM -0500, Jon Tollefson wrote:
> Instead of using the variable mmu_huge_psize to keep track of the huge
> page size we use an array of MMU_PAGE_* values.  For each supported
> huge page size we need to know the hugepte_shift value and have a
> pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
> functions so that they know which huge page size they should use.
> 
> The hugepage sizes 16M and 64K are setup(if available on the
> hardware) so that they don't have to be set on the boot cmd line in
> order to use them.  The number of 16G pages have to be specified at
> boot-time though (e.g. hugepagesz=16G hugepages=5).
> 
> 
> Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
> ---
> 
> @@ -150,17 +191,25 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned 
> long addr)
> 	pud_t *pu;
> 	pmd_t *pm;
> 
> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
> +	unsigned int psize;
> +	unsigned int shift;
> +	unsigned long sz;
> +	struct hstate *hstate;
> +	psize = get_slice_psize(mm, addr);
> +	shift = mmu_psize_to_shift(psize);
> +	sz = ((1UL) << shift);
> +	hstate = size_to_hstate(sz);
> 
> -	addr &= HPAGE_MASK;
> +	addr &= hstate->mask;
> 
> 	pg = pgd_offset(mm, addr);
> 	if (!pgd_none(*pg)) {
> 		pu = pud_offset(pg, addr);
> 		if (!pud_none(*pu)) {
> -			pm = hpmd_offset(pu, addr);
> +			pm = hpmd_offset(pu, addr, hstate);
> 			if (!pmd_none(*pm))
> -				return hugepte_offset((hugepd_t *)pm, addr);
> +				return hugepte_offset((hugepd_t *)pm, addr,
> +						      hstate);
> 		}
> 	}

Hi Jon,

I just noticed in a few places like this, you might be doing more work
than really needed to get the HPAGE_MASK.

For a first-pass conversion, this is the right way to go (just manually
replace hugepage constants with hstate-> equivalents). However in this
case if you already know the page size, you should be able to work out
the shift from there, I think? That way you can avoid the size_to_hstate
call completely.

Anyway, just something to consider.

Thanks,
Nick
> 
> @@ -173,16 +222,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
> long addr, unsigned long sz
> 	pud_t *pu;
> 	pmd_t *pm;
> 	hugepd_t *hpdp = NULL;
> +	struct hstate *hstate;
> +	unsigned int psize;
> +	hstate = size_to_hstate(sz);
> 
> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
> +	psize = get_slice_psize(mm, addr);
> +	BUG_ON(!mmu_huge_psizes[psize]);
> 
> -	addr &= HPAGE_MASK;
> +	addr &= hstate->mask;
> 
> 	pg = pgd_offset(mm, addr);
> 	pu = pud_alloc(mm, pg, addr);
> 
> 	if (pu) {
> -		pm = hpmd_alloc(mm, pu, addr);
> +		pm = hpmd_alloc(mm, pu, addr, hstate);
> 		if (pm)
> 			hpdp = (hugepd_t *)pm;
> 	}
> @@ -190,10 +243,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
> long addr, unsigned long sz
> 	if (! hpdp)
> 		return NULL;
> 
> -	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
> +	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize))
> 		return NULL;
> 
> -	return hugepte_offset(hpdp, addr);
> +	return hugepte_offset(hpdp, addr, hstate);
> }
> 
> int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
> @@ -201,19 +254,22 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned 
> long *addr, pte_t *ptep)
> 	return 0;
> }
> 
> -static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
> +static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp,
> +			       unsigned int psize)
> {
> 	pte_t *hugepte = hugepd_page(*hpdp);
> 
> 	hpdp->pd = 0;
> 	tlb->need_flush = 1;
> -	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
> +	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte,
> +						 HUGEPTE_CACHE_NUM+psize-1,
> 						 PGF_CACHENUM_MASK));
> }
> 
> static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
> 				   unsigned long addr, unsigned long end,
> -				   unsigned long floor, unsigned long 
> ceiling)
> +				   unsigned long floor, unsigned long 
> ceiling,
> +				   unsigned int psize)
> {
> 	pmd_t *pmd;
> 	unsigned long next;
> @@ -225,7 +281,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather 
> *tlb, pud_t *pud,
> 		next = pmd_addr_end(addr, end);
> 		if (pmd_none(*pmd))
> 			continue;
> -		free_hugepte_range(tlb, (hugepd_t *)pmd);
> +		free_hugepte_range(tlb, (hugepd_t *)pmd, psize);
> 	} while (pmd++, addr = next, addr != end);
> 
> 	start &= PUD_MASK;
> @@ -251,6 +307,9 @@ static void hugetlb_free_pud_range(struct mmu_gather 
> *tlb, pgd_t *pgd,
> 	pud_t *pud;
> 	unsigned long next;
> 	unsigned long start;
> +	unsigned int shift;
> +	unsigned int psize = get_slice_psize(tlb->mm, addr);
> +	shift = mmu_psize_to_shift(psize);
> 
> 	start = addr;
> 	pud = pud_offset(pgd, addr);
> @@ -259,16 +318,18 @@ static void hugetlb_free_pud_range(struct mmu_gather 
> *tlb, pgd_t *pgd,
> #ifdef CONFIG_PPC_64K_PAGES
> 		if (pud_none_or_clear_bad(pud))
> 			continue;
> -		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
> +		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling,
> +				       psize);
> #else
> -		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
> +		if (shift == PAGE_SHIFT_64K) {
> 			if (pud_none_or_clear_bad(pud))
> 				continue;
> -			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, 
> ceiling);
> +			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
> +					       ceiling, psize);
> 		} else {
> 			if (pud_none(*pud))
> 				continue;
> -			free_hugepte_range(tlb, (hugepd_t *)pud);
> +			free_hugepte_range(tlb, (hugepd_t *)pud, psize);
> 		}
> #endif
> 	} while (pud++, addr = next, addr != end);
> @@ -336,27 +397,29 @@ void hugetlb_free_pgd_range(struct mmu_gather **tlb,
> 	 * now has no other vmas using it, so can be freed, we don't
> 	 * bother to round floor or end up - the tests don't need that.
> 	 */
> +	unsigned int psize = get_slice_psize((*tlb)->mm, addr);
> 
> -	addr &= HUGEPD_MASK;
> +	addr &= HUGEPD_MASK(psize);
> 	if (addr < floor) {
> -		addr += HUGEPD_SIZE;
> +		addr += HUGEPD_SIZE(psize);
> 		if (!addr)
> 			return;
> 	}
> 	if (ceiling) {
> -		ceiling &= HUGEPD_MASK;
> +		ceiling &= HUGEPD_MASK(psize);
> 		if (!ceiling)
> 			return;
> 	}
> 	if (end - 1 > ceiling - 1)
> -		end -= HUGEPD_SIZE;
> +		end -= HUGEPD_SIZE(psize);
> 	if (addr > end - 1)
> 		return;
> 
> 	start = addr;
> 	pgd = pgd_offset((*tlb)->mm, addr);
> 	do {
> -		BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
> +		psize = get_slice_psize((*tlb)->mm, addr);
> +		BUG_ON(!mmu_huge_psizes[psize]);
> 		next = pgd_addr_end(addr, end);
> 		if (pgd_none_or_clear_bad(pgd))
> 			continue;
> @@ -373,7 +436,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned 
> long addr,
> 		 * necessary anymore if we make hpte_need_flush() get the
> 		 * page size from the slices
> 		 */
> -		pte_update(mm, addr & HPAGE_MASK, ptep, ~0UL, 1);
> +		unsigned int psize = get_slice_psize(mm, addr);
> +		unsigned int shift = mmu_psize_to_shift(psize);
> +		unsigned long sz;
> +		sz = ((1UL) << shift);
> +		struct hstate *hstate = size_to_hstate(sz);
> +		pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1);
> 	}
> 	*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
> }
> @@ -390,14 +458,19 @@ follow_huge_addr(struct mm_struct *mm, unsigned long 
> address, int write)
> {
> 	pte_t *ptep;
> 	struct page *page;
> +	unsigned int mmu_psize = get_slice_psize(mm, address);
> 
> -	if (get_slice_psize(mm, address) != mmu_huge_psize)
> +	/* Verify it is a huge page else bail. */
> +	if (!mmu_huge_psizes[mmu_psize])
> 		return ERR_PTR(-EINVAL);
> 
> 	ptep = huge_pte_offset(mm, address);
> 	page = pte_page(*ptep);
> -	if (page)
> -		page += (address % HPAGE_SIZE) / PAGE_SIZE;
> +	if (page) {
> +		unsigned int shift = mmu_psize_to_shift(mmu_psize);
> +		unsigned long sz = ((1UL) << shift);
> +		page += (address % sz) / PAGE_SIZE;
> +	}
> 
> 	return page;
> }
> @@ -425,15 +498,16 @@ unsigned long hugetlb_get_unmapped_area(struct file 
> *file, unsigned long addr,
> 					unsigned long len, unsigned long 
> 					pgoff,
> 					unsigned long flags)
> {
> -	return slice_get_unmapped_area(addr, len, flags,
> -				       mmu_huge_psize, 1, 0);
> +	struct hstate *hstate = hstate_file(file);
> +	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
> +	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
> }
> 
> /*
>  * Called by asm hashtable.S for doing lazy icache flush
>  */
> static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
> -						  pte_t pte, int trap)
> +					pte_t pte, int trap, unsigned long 
> sz)
> {
> 	struct page *page;
> 	int i;
> @@ -446,7 +520,7 @@ static unsigned int 
> hash_huge_page_do_lazy_icache(unsigned long rflags,
> 	/* page is dirty */
> 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
> 		if (trap == 0x400) {
> -			for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
> +			for (i = 0; i < (sz / PAGE_SIZE); i++)
> 				__flush_dcache_icache(page_address(page+i));
> 			set_bit(PG_arch_1, &page->flags);
> 		} else {
> @@ -466,7 +540,12 @@ int hash_huge_page(struct mm_struct *mm, unsigned long 
> access,
> 	long slot;
> 	int err = 1;
> 	int ssize = user_segment_size(ea);
> +	unsigned int mmu_psize;
> +	int shift;
> +	mmu_psize = get_slice_psize(mm, ea);
> 
> +	if(!mmu_huge_psizes[mmu_psize])
> +		goto out;
> 	ptep = huge_pte_offset(mm, ea);
> 
> 	/* Search the Linux page table for a match with va */
> @@ -510,30 +589,32 @@ int hash_huge_page(struct mm_struct *mm, unsigned 
> long access,
> 	rflags = 0x2 | (!(new_pte & _PAGE_RW));
>  	/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
> 	rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
> +	shift = mmu_psize_to_shift(mmu_psize);
> +	unsigned long sz = ((1UL) << shift);
> 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
> 		/* No CPU has hugepages but lacks no execute, so we
> 		 * don't need to worry about that case */
> 		rflags = hash_huge_page_do_lazy_icache(rflags, 
> 		__pte(old_pte),
> -						       trap);
> +						       trap, sz);
> 
> 	/* Check if pte already has an hpte (case 2) */
> 	if (unlikely(old_pte & _PAGE_HASHPTE)) {
> 		/* There MIGHT be an HPTE for this pte */
> 		unsigned long hash, slot;
> 
> -		hash = hpt_hash(va, HPAGE_SHIFT, ssize);
> +		hash = hpt_hash(va, shift, ssize);
> 		if (old_pte & _PAGE_F_SECOND)
> 			hash = ~hash;
> 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
> 		slot += (old_pte & _PAGE_F_GIX) >> 12;
> 
> -		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
> +		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize,
> 					 ssize, local) == -1)
> 			old_pte &= ~_PAGE_HPTEFLAGS;
> 	}
> 
> 	if (likely(!(old_pte & _PAGE_HASHPTE))) {
> -		unsigned long hash = hpt_hash(va, HPAGE_SHIFT, ssize);
> +		unsigned long hash = hpt_hash(va, shift, ssize);
> 		unsigned long hpte_group;
> 
> 		pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
> @@ -552,7 +633,7 @@ repeat:
> 
> 		/* Insert into the hash table, primary slot */
> 		slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
> -					  mmu_huge_psize, ssize);
> +					  mmu_psize, ssize);
> 
> 		/* Primary is full, try the secondary */
> 		if (unlikely(slot == -1)) {
> @@ -560,7 +641,7 @@ repeat:
> 				      HPTES_PER_GROUP) & ~0x7UL; 
> 			slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
> 						  HPTE_V_SECONDARY,
> -						  mmu_huge_psize, ssize);
> +						  mmu_psize, ssize);
> 			if (slot == -1) {
> 				if (mftb() & 0x1)
> 					hpte_group = ((hash & 
> 					htab_hash_mask) *
> @@ -597,35 +678,34 @@ void set_huge_psize(int psize)
> 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
> -		/* Return if huge page size is the same as the
> -		 * base page size. */
> -		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
> +		/* Return if huge page size has already been setup or is the
> +		 * same as the base page size. */
> +		if (mmu_huge_psizes[psize] ||
> +		   mmu_psize_defs[psize].shift == PAGE_SHIFT)
> 			return;
> +		huge_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT);
> 
> -		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
> -		mmu_huge_psize = psize;
> -
> -		switch (HPAGE_SHIFT) {
> +		switch (mmu_psize_defs[psize].shift) {
> 		case PAGE_SHIFT_64K:
> 		    /* We only allow 64k hpages with 4k base page,
> 		     * which was checked above, and always put them
> 		     * at the PMD */
> -		    hugepte_shift = PMD_SHIFT;
> +		    hugepte_shift[psize] = PMD_SHIFT;
> 		    break;
> 		case PAGE_SHIFT_16M:
> 		    /* 16M pages can be at two different levels
> 		     * of pagestables based on base page size */
> 		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
> -			    hugepte_shift = PMD_SHIFT;
> +			    hugepte_shift[psize] = PMD_SHIFT;
> 		    else /* 4k base page */
> -			    hugepte_shift = PUD_SHIFT;
> +			    hugepte_shift[psize] = PUD_SHIFT;
> 		    break;
> 		case PAGE_SHIFT_16G:
> 		    /* 16G pages are always at PGD level */
> -		    hugepte_shift = PGDIR_SHIFT;
> +		    hugepte_shift[psize] = PGDIR_SHIFT;
> 		    break;
> 		}
> -		hugepte_shift -= HPAGE_SHIFT;
> +		hugepte_shift[psize] -= mmu_psize_defs[psize].shift;
> 	} else
> 		HPAGE_SHIFT = 0;
> }
> @@ -633,30 +713,15 @@ void set_huge_psize(int psize)
> static int __init hugepage_setup_sz(char *str)
> {
> 	unsigned long long size;
> -	int mmu_psize = -1;
> +	int mmu_psize;
> 	int shift;
> 
> 	size = memparse(str, &str);
> 
> 	shift = __ffs(size);
> -	switch (shift) {
> -#ifndef CONFIG_PPC_64K_PAGES
> -	case PAGE_SHIFT_64K:
> -		mmu_psize = MMU_PAGE_64K;
> -		break;
> -#endif
> -	case PAGE_SHIFT_16M:
> -		mmu_psize = MMU_PAGE_16M;
> -		break;
> -	case PAGE_SHIFT_16G:
> -		mmu_psize = MMU_PAGE_16G;
> -		break;
> -	}
> -
> -	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
> +	mmu_psize = shift_to_mmu_psize(shift);
> +	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift)
> 		set_huge_psize(mmu_psize);
> -		huge_add_hstate(shift - PAGE_SHIFT);
> -	}
> 	else
> 		printk(KERN_WARNING "Invalid huge page size 
> 		specified(%llu)\n", size);
> 
> @@ -671,16 +736,30 @@ static void zero_ctor(struct kmem_cache *cache, void 
> *addr)
> 
> static int __init hugetlbpage_init(void)
> {
> +	unsigned int psize;
> 	if (!cpu_has_feature(CPU_FTR_16M_PAGE))
> 		return -ENODEV;
> -
> -	huge_pgtable_cache = kmem_cache_create("hugepte_cache",
> -					       HUGEPTE_TABLE_SIZE,
> -					       HUGEPTE_TABLE_SIZE,
> -					       0,
> -					       zero_ctor);
> -	if (! huge_pgtable_cache)
> -		panic("hugetlbpage_init(): could not create hugepte 
> cache\n");
> +	/* Add supported huge page sizes.  Need to change HUGE_MAX_HSTATE
> +	 * and adjust PTE_NONCACHE_NUM if the number of supported huge page
> +	 * sizes changes.
> +	 */
> +	set_huge_psize(MMU_PAGE_16M);
> +	set_huge_psize(MMU_PAGE_64K);
> +	set_huge_psize(MMU_PAGE_16G);
> +
> +	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
> +		if (mmu_huge_psizes[psize]) {
> +			huge_pgtable_cache(psize) = kmem_cache_create(
> +						HUGEPTE_CACHE_NAME(psize),
> +						HUGEPTE_TABLE_SIZE(psize),
> +						HUGEPTE_TABLE_SIZE(psize),
> +						0,
> +						zero_ctor);
> +			if (!huge_pgtable_cache(psize))
> +				panic("hugetlbpage_init(): could not create 
> %s"\
> +				      "\n", HUGEPTE_CACHE_NAME(psize));
> +		}
> +	}
> 
> 	return 0;
> }
> diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
> index c0f5cff..55588d5 100644
> --- a/arch/powerpc/mm/init_64.c
> +++ b/arch/powerpc/mm/init_64.c
> @@ -151,10 +151,10 @@ static const char 
> *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
> };
> 
> #ifdef CONFIG_HUGETLB_PAGE
> -/* Hugepages need one extra cache, initialized in hugetlbpage.c.  We
> - * can't put into the tables above, because HPAGE_SHIFT is not compile
> - * time constant. */
> -struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+1];
> +/* Hugepages need an extra cache per hugepagesize, initialized in
> + * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
> + * is not compile time constant. */
> +struct kmem_cache 
> *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
> #else
> struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
> #endif
> diff --git a/arch/powerpc/mm/tlb_64.c b/arch/powerpc/mm/tlb_64.c
> index e2d867c..8d79e16 100644
> --- a/arch/powerpc/mm/tlb_64.c
> +++ b/arch/powerpc/mm/tlb_64.c
> @@ -150,7 +150,7 @@ void hpte_need_flush(struct mm_struct *mm, unsigned 
> long addr,
> 	 */
> 	if (huge) {
> #ifdef CONFIG_HUGETLB_PAGE
> -		psize = mmu_huge_psize;
> +		psize = get_slice_psize(mm, addr);;
> #else
> 		BUG();
> 		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */
> diff --git a/include/asm-powerpc/mmu-hash64.h 
> b/include/asm-powerpc/mmu-hash64.h
> index db1276a..63b0fa5 100644
> --- a/include/asm-powerpc/mmu-hash64.h
> +++ b/include/asm-powerpc/mmu-hash64.h
> @@ -192,9 +192,9 @@ extern int mmu_ci_restrictions;
> 
> #ifdef CONFIG_HUGETLB_PAGE
> /*
> - * The page size index of the huge pages for use by hugetlbfs
> + * The page size indexes of the huge pages for use by hugetlbfs
>  */
> -extern int mmu_huge_psize;
> +extern unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
> 
> #endif /* CONFIG_HUGETLB_PAGE */
> 
> diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h
> index 67834ea..bdf453b 100644
> --- a/include/asm-powerpc/page_64.h
> +++ b/include/asm-powerpc/page_64.h
> @@ -90,6 +90,7 @@ extern unsigned int HPAGE_SHIFT;
> #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
> #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
> #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
> +#define HUGE_MAX_HSTATE		3
> 
> #endif /* __ASSEMBLY__ */
> 
> diff --git a/include/asm-powerpc/pgalloc-64.h 
> b/include/asm-powerpc/pgalloc-64.h
> index 6898099..812a1d8 100644
> --- a/include/asm-powerpc/pgalloc-64.h
> +++ b/include/asm-powerpc/pgalloc-64.h
> @@ -22,7 +22,7 @@ extern struct kmem_cache *pgtable_cache[];
> #define PUD_CACHE_NUM		1
> #define PMD_CACHE_NUM		1
> #define HUGEPTE_CACHE_NUM	2
> -#define PTE_NONCACHE_NUM	3  /* from GFP rather than kmem_cache */
> +#define PTE_NONCACHE_NUM	7  /* from GFP rather than kmem_cache */
> 
> static inline pgd_t *pgd_alloc(struct mm_struct *mm)
> {
> @@ -119,7 +119,7 @@ static inline void pte_free(struct mm_struct *mm, 
> pgtable_t ptepage)
> 	__free_page(ptepage);
> }
> 
> -#define PGF_CACHENUM_MASK	0x3
> +#define PGF_CACHENUM_MASK	0x7
> 
> typedef struct pgtable_free {
> 	unsigned long val;
> 

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Re: [PATCH 6/6] powerpc: support multiple huge page sizes

[Nick Piggin]

On Tue, May 13, 2008 at 12:25:27PM -0500, Jon Tollefson wrote:
> Instead of using the variable mmu_huge_psize to keep track of the huge
> page size we use an array of MMU_PAGE_* values.  For each supported
> huge page size we need to know the hugepte_shift value and have a
> pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
> functions so that they know which huge page size they should use.
> 
> The hugepage sizes 16M and 64K are setup(if available on the
> hardware) so that they don't have to be set on the boot cmd line in
> order to use them.  The number of 16G pages have to be specified at
> boot-time though (e.g. hugepagesz=16G hugepages=5).
> 
> 
> Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
> ---
> 
> @@ -150,17 +191,25 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned 
> long addr)
> 	pud_t *pu;
> 	pmd_t *pm;
> 
> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
> +	unsigned int psize;
> +	unsigned int shift;
> +	unsigned long sz;
> +	struct hstate *hstate;
> +	psize = get_slice_psize(mm, addr);
> +	shift = mmu_psize_to_shift(psize);
> +	sz = ((1UL) << shift);
> +	hstate = size_to_hstate(sz);
> 
> -	addr &= HPAGE_MASK;
> +	addr &= hstate->mask;
> 
> 	pg = pgd_offset(mm, addr);
> 	if (!pgd_none(*pg)) {
> 		pu = pud_offset(pg, addr);
> 		if (!pud_none(*pu)) {
> -			pm = hpmd_offset(pu, addr);
> +			pm = hpmd_offset(pu, addr, hstate);
> 			if (!pmd_none(*pm))
> -				return hugepte_offset((hugepd_t *)pm, addr);
> +				return hugepte_offset((hugepd_t *)pm, addr,
> +						      hstate);
> 		}
> 	}

Hi Jon,

I just noticed in a few places like this, you might be doing more work
than really needed to get the HPAGE_MASK.

For a first-pass conversion, this is the right way to go (just manually
replace hugepage constants with hstate-> equivalents). However in this
case if you already know the page size, you should be able to work out
the shift from there, I think? That way you can avoid the size_to_hstate
call completely.

Anyway, just something to consider.

Thanks,
Nick
> 
> @@ -173,16 +222,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
> long addr, unsigned long sz
> 	pud_t *pu;
> 	pmd_t *pm;
> 	hugepd_t *hpdp = NULL;
> +	struct hstate *hstate;
> +	unsigned int psize;
> +	hstate = size_to_hstate(sz);
> 
> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
> +	psize = get_slice_psize(mm, addr);
> +	BUG_ON(!mmu_huge_psizes[psize]);
> 
> -	addr &= HPAGE_MASK;
> +	addr &= hstate->mask;
> 
> 	pg = pgd_offset(mm, addr);
> 	pu = pud_alloc(mm, pg, addr);
> 
> 	if (pu) {
> -		pm = hpmd_alloc(mm, pu, addr);
> +		pm = hpmd_alloc(mm, pu, addr, hstate);
> 		if (pm)
> 			hpdp = (hugepd_t *)pm;
> 	}
> @@ -190,10 +243,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
> long addr, unsigned long sz
> 	if (! hpdp)
> 		return NULL;
> 
> -	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
> +	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize))
> 		return NULL;
> 
> -	return hugepte_offset(hpdp, addr);
> +	return hugepte_offset(hpdp, addr, hstate);
> }
> 
> int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
> @@ -201,19 +254,22 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned 
> long *addr, pte_t *ptep)
> 	return 0;
> }
> 
> -static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
> +static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp,
> +			       unsigned int psize)
> {
> 	pte_t *hugepte = hugepd_page(*hpdp);
> 
> 	hpdp->pd = 0;
> 	tlb->need_flush = 1;
> -	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
> +	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte,
> +						 HUGEPTE_CACHE_NUM+psize-1,
> 						 PGF_CACHENUM_MASK));
> }
> 
> static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
> 				   unsigned long addr, unsigned long end,
> -				   unsigned long floor, unsigned long 
> ceiling)
> +				   unsigned long floor, unsigned long 
> ceiling,
> +				   unsigned int psize)
> {
> 	pmd_t *pmd;
> 	unsigned long next;
> @@ -225,7 +281,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather 
> *tlb, pud_t *pud,
> 		next = pmd_addr_end(addr, end);
> 		if (pmd_none(*pmd))
> 			continue;
> -		free_hugepte_range(tlb, (hugepd_t *)pmd);
> +		free_hugepte_range(tlb, (hugepd_t *)pmd, psize);
> 	} while (pmd++, addr = next, addr != end);
> 
> 	start &= PUD_MASK;
> @@ -251,6 +307,9 @@ static void hugetlb_free_pud_range(struct mmu_gather 
> *tlb, pgd_t *pgd,
> 	pud_t *pud;
> 	unsigned long next;
> 	unsigned long start;
> +	unsigned int shift;
> +	unsigned int psize = get_slice_psize(tlb->mm, addr);
> +	shift = mmu_psize_to_shift(psize);
> 
> 	start = addr;
> 	pud = pud_offset(pgd, addr);
> @@ -259,16 +318,18 @@ static void hugetlb_free_pud_range(struct mmu_gather 
> *tlb, pgd_t *pgd,
> #ifdef CONFIG_PPC_64K_PAGES
> 		if (pud_none_or_clear_bad(pud))
> 			continue;
> -		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
> +		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling,
> +				       psize);
> #else
> -		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
> +		if (shift == PAGE_SHIFT_64K) {
> 			if (pud_none_or_clear_bad(pud))
> 				continue;
> -			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, 
> ceiling);
> +			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
> +					       ceiling, psize);
> 		} else {
> 			if (pud_none(*pud))
> 				continue;
> -			free_hugepte_range(tlb, (hugepd_t *)pud);
> +			free_hugepte_range(tlb, (hugepd_t *)pud, psize);
> 		}
> #endif
> 	} while (pud++, addr = next, addr != end);
> @@ -336,27 +397,29 @@ void hugetlb_free_pgd_range(struct mmu_gather **tlb,
> 	 * now has no other vmas using it, so can be freed, we don't
> 	 * bother to round floor or end up - the tests don't need that.
> 	 */
> +	unsigned int psize = get_slice_psize((*tlb)->mm, addr);
> 
> -	addr &= HUGEPD_MASK;
> +	addr &= HUGEPD_MASK(psize);
> 	if (addr < floor) {
> -		addr += HUGEPD_SIZE;
> +		addr += HUGEPD_SIZE(psize);
> 		if (!addr)
> 			return;
> 	}
> 	if (ceiling) {
> -		ceiling &= HUGEPD_MASK;
> +		ceiling &= HUGEPD_MASK(psize);
> 		if (!ceiling)
> 			return;
> 	}
> 	if (end - 1 > ceiling - 1)
> -		end -= HUGEPD_SIZE;
> +		end -= HUGEPD_SIZE(psize);
> 	if (addr > end - 1)
> 		return;
> 
> 	start = addr;
> 	pgd = pgd_offset((*tlb)->mm, addr);
> 	do {
> -		BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
> +		psize = get_slice_psize((*tlb)->mm, addr);
> +		BUG_ON(!mmu_huge_psizes[psize]);
> 		next = pgd_addr_end(addr, end);
> 		if (pgd_none_or_clear_bad(pgd))
> 			continue;
> @@ -373,7 +436,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned 
> long addr,
> 		 * necessary anymore if we make hpte_need_flush() get the
> 		 * page size from the slices
> 		 */
> -		pte_update(mm, addr & HPAGE_MASK, ptep, ~0UL, 1);
> +		unsigned int psize = get_slice_psize(mm, addr);
> +		unsigned int shift = mmu_psize_to_shift(psize);
> +		unsigned long sz;
> +		sz = ((1UL) << shift);
> +		struct hstate *hstate = size_to_hstate(sz);
> +		pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1);
> 	}
> 	*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
> }
> @@ -390,14 +458,19 @@ follow_huge_addr(struct mm_struct *mm, unsigned long 
> address, int write)
> {
> 	pte_t *ptep;
> 	struct page *page;
> +	unsigned int mmu_psize = get_slice_psize(mm, address);
> 
> -	if (get_slice_psize(mm, address) != mmu_huge_psize)
> +	/* Verify it is a huge page else bail. */
> +	if (!mmu_huge_psizes[mmu_psize])
> 		return ERR_PTR(-EINVAL);
> 
> 	ptep = huge_pte_offset(mm, address);
> 	page = pte_page(*ptep);
> -	if (page)
> -		page += (address % HPAGE_SIZE) / PAGE_SIZE;
> +	if (page) {
> +		unsigned int shift = mmu_psize_to_shift(mmu_psize);
> +		unsigned long sz = ((1UL) << shift);
> +		page += (address % sz) / PAGE_SIZE;
> +	}
> 
> 	return page;
> }
> @@ -425,15 +498,16 @@ unsigned long hugetlb_get_unmapped_area(struct file 
> *file, unsigned long addr,
> 					unsigned long len, unsigned long 
> 					pgoff,
> 					unsigned long flags)
> {
> -	return slice_get_unmapped_area(addr, len, flags,
> -				       mmu_huge_psize, 1, 0);
> +	struct hstate *hstate = hstate_file(file);
> +	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
> +	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
> }
> 
> /*
>  * Called by asm hashtable.S for doing lazy icache flush
>  */
> static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
> -						  pte_t pte, int trap)
> +					pte_t pte, int trap, unsigned long 
> sz)
> {
> 	struct page *page;
> 	int i;
> @@ -446,7 +520,7 @@ static unsigned int 
> hash_huge_page_do_lazy_icache(unsigned long rflags,
> 	/* page is dirty */
> 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
> 		if (trap == 0x400) {
> -			for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
> +			for (i = 0; i < (sz / PAGE_SIZE); i++)
> 				__flush_dcache_icache(page_address(page+i));
> 			set_bit(PG_arch_1, &page->flags);
> 		} else {
> @@ -466,7 +540,12 @@ int hash_huge_page(struct mm_struct *mm, unsigned long 
> access,
> 	long slot;
> 	int err = 1;
> 	int ssize = user_segment_size(ea);
> +	unsigned int mmu_psize;
> +	int shift;
> +	mmu_psize = get_slice_psize(mm, ea);
> 
> +	if(!mmu_huge_psizes[mmu_psize])
> +		goto out;
> 	ptep = huge_pte_offset(mm, ea);
> 
> 	/* Search the Linux page table for a match with va */
> @@ -510,30 +589,32 @@ int hash_huge_page(struct mm_struct *mm, unsigned 
> long access,
> 	rflags = 0x2 | (!(new_pte & _PAGE_RW));
>  	/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
> 	rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
> +	shift = mmu_psize_to_shift(mmu_psize);
> +	unsigned long sz = ((1UL) << shift);
> 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
> 		/* No CPU has hugepages but lacks no execute, so we
> 		 * don't need to worry about that case */
> 		rflags = hash_huge_page_do_lazy_icache(rflags, 
> 		__pte(old_pte),
> -						       trap);
> +						       trap, sz);
> 
> 	/* Check if pte already has an hpte (case 2) */
> 	if (unlikely(old_pte & _PAGE_HASHPTE)) {
> 		/* There MIGHT be an HPTE for this pte */
> 		unsigned long hash, slot;
> 
> -		hash = hpt_hash(va, HPAGE_SHIFT, ssize);
> +		hash = hpt_hash(va, shift, ssize);
> 		if (old_pte & _PAGE_F_SECOND)
> 			hash = ~hash;
> 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
> 		slot += (old_pte & _PAGE_F_GIX) >> 12;
> 
> -		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
> +		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize,
> 					 ssize, local) == -1)
> 			old_pte &= ~_PAGE_HPTEFLAGS;
> 	}
> 
> 	if (likely(!(old_pte & _PAGE_HASHPTE))) {
> -		unsigned long hash = hpt_hash(va, HPAGE_SHIFT, ssize);
> +		unsigned long hash = hpt_hash(va, shift, ssize);
> 		unsigned long hpte_group;
> 
> 		pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
> @@ -552,7 +633,7 @@ repeat:
> 
> 		/* Insert into the hash table, primary slot */
> 		slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
> -					  mmu_huge_psize, ssize);
> +					  mmu_psize, ssize);
> 
> 		/* Primary is full, try the secondary */
> 		if (unlikely(slot == -1)) {
> @@ -560,7 +641,7 @@ repeat:
> 				      HPTES_PER_GROUP) & ~0x7UL; 
> 			slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
> 						  HPTE_V_SECONDARY,
> -						  mmu_huge_psize, ssize);
> +						  mmu_psize, ssize);
> 			if (slot == -1) {
> 				if (mftb() & 0x1)
> 					hpte_group = ((hash & 
> 					htab_hash_mask) *
> @@ -597,35 +678,34 @@ void set_huge_psize(int psize)
> 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
> -		/* Return if huge page size is the same as the
> -		 * base page size. */
> -		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
> +		/* Return if huge page size has already been setup or is the
> +		 * same as the base page size. */
> +		if (mmu_huge_psizes[psize] ||
> +		   mmu_psize_defs[psize].shift == PAGE_SHIFT)
> 			return;
> +		huge_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT);
> 
> -		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
> -		mmu_huge_psize = psize;
> -
> -		switch (HPAGE_SHIFT) {
> +		switch (mmu_psize_defs[psize].shift) {
> 		case PAGE_SHIFT_64K:
> 		    /* We only allow 64k hpages with 4k base page,
> 		     * which was checked above, and always put them
> 		     * at the PMD */
> -		    hugepte_shift = PMD_SHIFT;
> +		    hugepte_shift[psize] = PMD_SHIFT;
> 		    break;
> 		case PAGE_SHIFT_16M:
> 		    /* 16M pages can be at two different levels
> 		     * of pagestables based on base page size */
> 		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
> -			    hugepte_shift = PMD_SHIFT;
> +			    hugepte_shift[psize] = PMD_SHIFT;
> 		    else /* 4k base page */
> -			    hugepte_shift = PUD_SHIFT;
> +			    hugepte_shift[psize] = PUD_SHIFT;
> 		    break;
> 		case PAGE_SHIFT_16G:
> 		    /* 16G pages are always at PGD level */
> -		    hugepte_shift = PGDIR_SHIFT;
> +		    hugepte_shift[psize] = PGDIR_SHIFT;
> 		    break;
> 		}
> -		hugepte_shift -= HPAGE_SHIFT;
> +		hugepte_shift[psize] -= mmu_psize_defs[psize].shift;
> 	} else
> 		HPAGE_SHIFT = 0;
> }
> @@ -633,30 +713,15 @@ void set_huge_psize(int psize)
> static int __init hugepage_setup_sz(char *str)
> {
> 	unsigned long long size;
> -	int mmu_psize = -1;
> +	int mmu_psize;
> 	int shift;
> 
> 	size = memparse(str, &str);
> 
> 	shift = __ffs(size);
> -	switch (shift) {
> -#ifndef CONFIG_PPC_64K_PAGES
> -	case PAGE_SHIFT_64K:
> -		mmu_psize = MMU_PAGE_64K;
> -		break;
> -#endif
> -	case PAGE_SHIFT_16M:
> -		mmu_psize = MMU_PAGE_16M;
> -		break;
> -	case PAGE_SHIFT_16G:
> -		mmu_psize = MMU_PAGE_16G;
> -		break;
> -	}
> -
> -	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
> +	mmu_psize = shift_to_mmu_psize(shift);
> +	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift)
> 		set_huge_psize(mmu_psize);
> -		huge_add_hstate(shift - PAGE_SHIFT);
> -	}
> 	else
> 		printk(KERN_WARNING "Invalid huge page size 
> 		specified(%llu)\n", size);
> 
> @@ -671,16 +736,30 @@ static void zero_ctor(struct kmem_cache *cache, void 
> *addr)
> 
> static int __init hugetlbpage_init(void)
> {
> +	unsigned int psize;
> 	if (!cpu_has_feature(CPU_FTR_16M_PAGE))
> 		return -ENODEV;
> -
> -	huge_pgtable_cache = kmem_cache_create("hugepte_cache",
> -					       HUGEPTE_TABLE_SIZE,
> -					       HUGEPTE_TABLE_SIZE,
> -					       0,
> -					       zero_ctor);
> -	if (! huge_pgtable_cache)
> -		panic("hugetlbpage_init(): could not create hugepte 
> cache\n");
> +	/* Add supported huge page sizes.  Need to change HUGE_MAX_HSTATE
> +	 * and adjust PTE_NONCACHE_NUM if the number of supported huge page
> +	 * sizes changes.
> +	 */
> +	set_huge_psize(MMU_PAGE_16M);
> +	set_huge_psize(MMU_PAGE_64K);
> +	set_huge_psize(MMU_PAGE_16G);
> +
> +	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
> +		if (mmu_huge_psizes[psize]) {
> +			huge_pgtable_cache(psize) = kmem_cache_create(
> +						HUGEPTE_CACHE_NAME(psize),
> +						HUGEPTE_TABLE_SIZE(psize),
> +						HUGEPTE_TABLE_SIZE(psize),
> +						0,
> +						zero_ctor);
> +			if (!huge_pgtable_cache(psize))
> +				panic("hugetlbpage_init(): could not create 
> %s"\
> +				      "\n", HUGEPTE_CACHE_NAME(psize));
> +		}
> +	}
> 
> 	return 0;
> }
> diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
> index c0f5cff..55588d5 100644
> --- a/arch/powerpc/mm/init_64.c
> +++ b/arch/powerpc/mm/init_64.c
> @@ -151,10 +151,10 @@ static const char 
> *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
> };
> 
> #ifdef CONFIG_HUGETLB_PAGE
> -/* Hugepages need one extra cache, initialized in hugetlbpage.c.  We
> - * can't put into the tables above, because HPAGE_SHIFT is not compile
> - * time constant. */
> -struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+1];
> +/* Hugepages need an extra cache per hugepagesize, initialized in
> + * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
> + * is not compile time constant. */
> +struct kmem_cache 
> *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
> #else
> struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
> #endif
> diff --git a/arch/powerpc/mm/tlb_64.c b/arch/powerpc/mm/tlb_64.c
> index e2d867c..8d79e16 100644
> --- a/arch/powerpc/mm/tlb_64.c
> +++ b/arch/powerpc/mm/tlb_64.c
> @@ -150,7 +150,7 @@ void hpte_need_flush(struct mm_struct *mm, unsigned 
> long addr,
> 	 */
> 	if (huge) {
> #ifdef CONFIG_HUGETLB_PAGE
> -		psize = mmu_huge_psize;
> +		psize = get_slice_psize(mm, addr);;
> #else
> 		BUG();
> 		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */
> diff --git a/include/asm-powerpc/mmu-hash64.h 
> b/include/asm-powerpc/mmu-hash64.h
> index db1276a..63b0fa5 100644
> --- a/include/asm-powerpc/mmu-hash64.h
> +++ b/include/asm-powerpc/mmu-hash64.h
> @@ -192,9 +192,9 @@ extern int mmu_ci_restrictions;
> 
> #ifdef CONFIG_HUGETLB_PAGE
> /*
> - * The page size index of the huge pages for use by hugetlbfs
> + * The page size indexes of the huge pages for use by hugetlbfs
>  */
> -extern int mmu_huge_psize;
> +extern unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
> 
> #endif /* CONFIG_HUGETLB_PAGE */
> 
> diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h
> index 67834ea..bdf453b 100644
> --- a/include/asm-powerpc/page_64.h
> +++ b/include/asm-powerpc/page_64.h
> @@ -90,6 +90,7 @@ extern unsigned int HPAGE_SHIFT;
> #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
> #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
> #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
> +#define HUGE_MAX_HSTATE		3
> 
> #endif /* __ASSEMBLY__ */
> 
> diff --git a/include/asm-powerpc/pgalloc-64.h 
> b/include/asm-powerpc/pgalloc-64.h
> index 6898099..812a1d8 100644
> --- a/include/asm-powerpc/pgalloc-64.h
> +++ b/include/asm-powerpc/pgalloc-64.h
> @@ -22,7 +22,7 @@ extern struct kmem_cache *pgtable_cache[];
> #define PUD_CACHE_NUM		1
> #define PMD_CACHE_NUM		1
> #define HUGEPTE_CACHE_NUM	2
> -#define PTE_NONCACHE_NUM	3  /* from GFP rather than kmem_cache */
> +#define PTE_NONCACHE_NUM	7  /* from GFP rather than kmem_cache */
> 
> static inline pgd_t *pgd_alloc(struct mm_struct *mm)
> {
> @@ -119,7 +119,7 @@ static inline void pte_free(struct mm_struct *mm, 
> pgtable_t ptepage)
> 	__free_page(ptepage);
> }
> 
> -#define PGF_CACHENUM_MASK	0x3
> +#define PGF_CACHENUM_MASK	0x7
> 
> typedef struct pgtable_free {
> 	unsigned long val;
> 

Re: [PATCH 6/6] powerpc: support multiple huge page sizes

[Jon Tollefson]

Nick Piggin wrote:
> On Tue, May 13, 2008 at 12:25:27PM -0500, Jon Tollefson wrote:
>   
>> Instead of using the variable mmu_huge_psize to keep track of the huge
>> page size we use an array of MMU_PAGE_* values.  For each supported
>> huge page size we need to know the hugepte_shift value and have a
>> pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
>> functions so that they know which huge page size they should use.
>>
>> The hugepage sizes 16M and 64K are setup(if available on the
>> hardware) so that they don't have to be set on the boot cmd line in
>> order to use them.  The number of 16G pages have to be specified at
>> boot-time though (e.g. hugepagesz=16G hugepages=5).
>>
>>
>> Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
>> ---
>>
>> @@ -150,17 +191,25 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned 
>> long addr)
>> 	pud_t *pu;
>> 	pmd_t *pm;
>>
>> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
>> +	unsigned int psize;
>> +	unsigned int shift;
>> +	unsigned long sz;
>> +	struct hstate *hstate;
>> +	psize = get_slice_psize(mm, addr);
>> +	shift = mmu_psize_to_shift(psize);
>> +	sz = ((1UL) << shift);
>> +	hstate = size_to_hstate(sz);
>>
>> -	addr &= HPAGE_MASK;
>> +	addr &= hstate->mask;
>>
>> 	pg = pgd_offset(mm, addr);
>> 	if (!pgd_none(*pg)) {
>> 		pu = pud_offset(pg, addr);
>> 		if (!pud_none(*pu)) {
>> -			pm = hpmd_offset(pu, addr);
>> +			pm = hpmd_offset(pu, addr, hstate);
>> 			if (!pmd_none(*pm))
>> -				return hugepte_offset((hugepd_t *)pm, addr);
>> +				return hugepte_offset((hugepd_t *)pm, addr,
>> +						      hstate);
>> 		}
>> 	}
>>     
>
> Hi Jon,
>
> I just noticed in a few places like this, you might be doing more work
> than really needed to get the HPAGE_MASK.
>   
I would love to be able to simplify it.
> For a first-pass conversion, this is the right way to go (just manually
> replace hugepage constants with hstate-> equivalents). However in this
> case if you already know the page size, you should be able to work out
> the shift from there, I think? That way you can avoid the size_to_hstate
> call completely.
>   
Something like the following?

+	addr &= ~(sz - 1);

Is that faster then just pulling it out of hstate?
I still need to locate hstate, but I guess if the mask is calculated
this way the locate could be pushed further into the function so that it
isn't done if it isn't always needed.
> Anyway, just something to consider.
>
> Thanks,
> Nick
>   
Thank you for looking at the code.

Jon

>> @@ -173,16 +222,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
>> long addr, unsigned long sz
>> 	pud_t *pu;
>> 	pmd_t *pm;
>> 	hugepd_t *hpdp = NULL;
>> +	struct hstate *hstate;
>> +	unsigned int psize;
>> +	hstate = size_to_hstate(sz);
>>
>> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
>> +	psize = get_slice_psize(mm, addr);
>> +	BUG_ON(!mmu_huge_psizes[psize]);
>>
>> -	addr &= HPAGE_MASK;
>> +	addr &= hstate->mask;
>>
>> 	pg = pgd_offset(mm, addr);
>> 	pu = pud_alloc(mm, pg, addr);
>>
>> 	if (pu) {
>> -		pm = hpmd_alloc(mm, pu, addr);
>> +		pm = hpmd_alloc(mm, pu, addr, hstate);
>> 		if (pm)
>> 			hpdp = (hugepd_t *)pm;
>> 	}
>> @@ -190,10 +243,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
>> long addr, unsigned long sz
>> 	if (! hpdp)
>> 		return NULL;
>>
>> -	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
>> +	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize))
>> 		return NULL;
>>
>> -	return hugepte_offset(hpdp, addr);
>> +	return hugepte_offset(hpdp, addr, hstate);
>> }
>>
>> int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
>> @@ -201,19 +254,22 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned 
>> long *addr, pte_t *ptep)
>> 	return 0;
>> }
>>
>> -static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
>> +static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp,
>> +			       unsigned int psize)
>> {
>> 	pte_t *hugepte = hugepd_page(*hpdp);
>>
>> 	hpdp->pd = 0;
>> 	tlb->need_flush = 1;
>> -	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
>> +	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte,
>> +						 HUGEPTE_CACHE_NUM+psize-1,
>> 						 PGF_CACHENUM_MASK));
>> }
>>
>> static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
>> 				   unsigned long addr, unsigned long end,
>> -				   unsigned long floor, unsigned long 
>> ceiling)
>> +				   unsigned long floor, unsigned long 
>> ceiling,
>> +				   unsigned int psize)
>> {
>> 	pmd_t *pmd;
>> 	unsigned long next;
>> @@ -225,7 +281,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather 
>> *tlb, pud_t *pud,
>> 		next = pmd_addr_end(addr, end);
>> 		if (pmd_none(*pmd))
>> 			continue;
>> -		free_hugepte_range(tlb, (hugepd_t *)pmd);
>> +		free_hugepte_range(tlb, (hugepd_t *)pmd, psize);
>> 	} while (pmd++, addr = next, addr != end);
>>
>> 	start &= PUD_MASK;
>> @@ -251,6 +307,9 @@ static void hugetlb_free_pud_range(struct mmu_gather 
>> *tlb, pgd_t *pgd,
>> 	pud_t *pud;
>> 	unsigned long next;
>> 	unsigned long start;
>> +	unsigned int shift;
>> +	unsigned int psize = get_slice_psize(tlb->mm, addr);
>> +	shift = mmu_psize_to_shift(psize);
>>
>> 	start = addr;
>> 	pud = pud_offset(pgd, addr);
>> @@ -259,16 +318,18 @@ static void hugetlb_free_pud_range(struct mmu_gather 
>> *tlb, pgd_t *pgd,
>> #ifdef CONFIG_PPC_64K_PAGES
>> 		if (pud_none_or_clear_bad(pud))
>> 			continue;
>> -		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
>> +		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling,
>> +				       psize);
>> #else
>> -		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
>> +		if (shift == PAGE_SHIFT_64K) {
>> 			if (pud_none_or_clear_bad(pud))
>> 				continue;
>> -			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, 
>> ceiling);
>> +			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
>> +					       ceiling, psize);
>> 		} else {
>> 			if (pud_none(*pud))
>> 				continue;
>> -			free_hugepte_range(tlb, (hugepd_t *)pud);
>> +			free_hugepte_range(tlb, (hugepd_t *)pud, psize);
>> 		}
>> #endif
>> 	} while (pud++, addr = next, addr != end);
>> @@ -336,27 +397,29 @@ void hugetlb_free_pgd_range(struct mmu_gather **tlb,
>> 	 * now has no other vmas using it, so can be freed, we don't
>> 	 * bother to round floor or end up - the tests don't need that.
>> 	 */
>> +	unsigned int psize = get_slice_psize((*tlb)->mm, addr);
>>
>> -	addr &= HUGEPD_MASK;
>> +	addr &= HUGEPD_MASK(psize);
>> 	if (addr < floor) {
>> -		addr += HUGEPD_SIZE;
>> +		addr += HUGEPD_SIZE(psize);
>> 		if (!addr)
>> 			return;
>> 	}
>> 	if (ceiling) {
>> -		ceiling &= HUGEPD_MASK;
>> +		ceiling &= HUGEPD_MASK(psize);
>> 		if (!ceiling)
>> 			return;
>> 	}
>> 	if (end - 1 > ceiling - 1)
>> -		end -= HUGEPD_SIZE;
>> +		end -= HUGEPD_SIZE(psize);
>> 	if (addr > end - 1)
>> 		return;
>>
>> 	start = addr;
>> 	pgd = pgd_offset((*tlb)->mm, addr);
>> 	do {
>> -		BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
>> +		psize = get_slice_psize((*tlb)->mm, addr);
>> +		BUG_ON(!mmu_huge_psizes[psize]);
>> 		next = pgd_addr_end(addr, end);
>> 		if (pgd_none_or_clear_bad(pgd))
>> 			continue;
>> @@ -373,7 +436,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned 
>> long addr,
>> 		 * necessary anymore if we make hpte_need_flush() get the
>> 		 * page size from the slices
>> 		 */
>> -		pte_update(mm, addr & HPAGE_MASK, ptep, ~0UL, 1);
>> +		unsigned int psize = get_slice_psize(mm, addr);
>> +		unsigned int shift = mmu_psize_to_shift(psize);
>> +		unsigned long sz;
>> +		sz = ((1UL) << shift);
>> +		struct hstate *hstate = size_to_hstate(sz);
>> +		pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1);
>> 	}
>> 	*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
>> }
>> @@ -390,14 +458,19 @@ follow_huge_addr(struct mm_struct *mm, unsigned long 
>> address, int write)
>> {
>> 	pte_t *ptep;
>> 	struct page *page;
>> +	unsigned int mmu_psize = get_slice_psize(mm, address);
>>
>> -	if (get_slice_psize(mm, address) != mmu_huge_psize)
>> +	/* Verify it is a huge page else bail. */
>> +	if (!mmu_huge_psizes[mmu_psize])
>> 		return ERR_PTR(-EINVAL);
>>
>> 	ptep = huge_pte_offset(mm, address);
>> 	page = pte_page(*ptep);
>> -	if (page)
>> -		page += (address % HPAGE_SIZE) / PAGE_SIZE;
>> +	if (page) {
>> +		unsigned int shift = mmu_psize_to_shift(mmu_psize);
>> +		unsigned long sz = ((1UL) << shift);
>> +		page += (address % sz) / PAGE_SIZE;
>> +	}
>>
>> 	return page;
>> }
>> @@ -425,15 +498,16 @@ unsigned long hugetlb_get_unmapped_area(struct file 
>> *file, unsigned long addr,
>> 					unsigned long len, unsigned long 
>> 					pgoff,
>> 					unsigned long flags)
>> {
>> -	return slice_get_unmapped_area(addr, len, flags,
>> -				       mmu_huge_psize, 1, 0);
>> +	struct hstate *hstate = hstate_file(file);
>> +	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
>> +	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
>> }
>>
>> /*
>>  * Called by asm hashtable.S for doing lazy icache flush
>>  */
>> static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
>> -						  pte_t pte, int trap)
>> +					pte_t pte, int trap, unsigned long 
>> sz)
>> {
>> 	struct page *page;
>> 	int i;
>> @@ -446,7 +520,7 @@ static unsigned int 
>> hash_huge_page_do_lazy_icache(unsigned long rflags,
>> 	/* page is dirty */
>> 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
>> 		if (trap == 0x400) {
>> -			for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
>> +			for (i = 0; i < (sz / PAGE_SIZE); i++)
>> 				__flush_dcache_icache(page_address(page+i));
>> 			set_bit(PG_arch_1, &page->flags);
>> 		} else {
>> @@ -466,7 +540,12 @@ int hash_huge_page(struct mm_struct *mm, unsigned long 
>> access,
>> 	long slot;
>> 	int err = 1;
>> 	int ssize = user_segment_size(ea);
>> +	unsigned int mmu_psize;
>> +	int shift;
>> +	mmu_psize = get_slice_psize(mm, ea);
>>
>> +	if(!mmu_huge_psizes[mmu_psize])
>> +		goto out;
>> 	ptep = huge_pte_offset(mm, ea);
>>
>> 	/* Search the Linux page table for a match with va */
>> @@ -510,30 +589,32 @@ int hash_huge_page(struct mm_struct *mm, unsigned 
>> long access,
>> 	rflags = 0x2 | (!(new_pte & _PAGE_RW));
>>  	/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
>> 	rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
>> +	shift = mmu_psize_to_shift(mmu_psize);
>> +	unsigned long sz = ((1UL) << shift);
>> 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
>> 		/* No CPU has hugepages but lacks no execute, so we
>> 		 * don't need to worry about that case */
>> 		rflags = hash_huge_page_do_lazy_icache(rflags, 
>> 		__pte(old_pte),
>> -						       trap);
>> +						       trap, sz);
>>
>> 	/* Check if pte already has an hpte (case 2) */
>> 	if (unlikely(old_pte & _PAGE_HASHPTE)) {
>> 		/* There MIGHT be an HPTE for this pte */
>> 		unsigned long hash, slot;
>>
>> -		hash = hpt_hash(va, HPAGE_SHIFT, ssize);
>> +		hash = hpt_hash(va, shift, ssize);
>> 		if (old_pte & _PAGE_F_SECOND)
>> 			hash = ~hash;
>> 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
>> 		slot += (old_pte & _PAGE_F_GIX) >> 12;
>>
>> -		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
>> +		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize,
>> 					 ssize, local) == -1)
>> 			old_pte &= ~_PAGE_HPTEFLAGS;
>> 	}
>>
>> 	if (likely(!(old_pte & _PAGE_HASHPTE))) {
>> -		unsigned long hash = hpt_hash(va, HPAGE_SHIFT, ssize);
>> +		unsigned long hash = hpt_hash(va, shift, ssize);
>> 		unsigned long hpte_group;
>>
>> 		pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
>> @@ -552,7 +633,7 @@ repeat:
>>
>> 		/* Insert into the hash table, primary slot */
>> 		slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
>> -					  mmu_huge_psize, ssize);
>> +					  mmu_psize, ssize);
>>
>> 		/* Primary is full, try the secondary */
>> 		if (unlikely(slot == -1)) {
>> @@ -560,7 +641,7 @@ repeat:
>> 				      HPTES_PER_GROUP) & ~0x7UL; 
>> 			slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
>> 						  HPTE_V_SECONDARY,
>> -						  mmu_huge_psize, ssize);
>> +						  mmu_psize, ssize);
>> 			if (slot == -1) {
>> 				if (mftb() & 0x1)
>> 					hpte_group = ((hash & 
>> 					htab_hash_mask) *
>> @@ -597,35 +678,34 @@ void set_huge_psize(int psize)
>> 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
>> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
>> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
>> -		/* Return if huge page size is the same as the
>> -		 * base page size. */
>> -		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
>> +		/* Return if huge page size has already been setup or is the
>> +		 * same as the base page size. */
>> +		if (mmu_huge_psizes[psize] ||
>> +		   mmu_psize_defs[psize].shift == PAGE_SHIFT)
>> 			return;
>> +		huge_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT);
>>
>> -		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
>> -		mmu_huge_psize = psize;
>> -
>> -		switch (HPAGE_SHIFT) {
>> +		switch (mmu_psize_defs[psize].shift) {
>> 		case PAGE_SHIFT_64K:
>> 		    /* We only allow 64k hpages with 4k base page,
>> 		     * which was checked above, and always put them
>> 		     * at the PMD */
>> -		    hugepte_shift = PMD_SHIFT;
>> +		    hugepte_shift[psize] = PMD_SHIFT;
>> 		    break;
>> 		case PAGE_SHIFT_16M:
>> 		    /* 16M pages can be at two different levels
>> 		     * of pagestables based on base page size */
>> 		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
>> -			    hugepte_shift = PMD_SHIFT;
>> +			    hugepte_shift[psize] = PMD_SHIFT;
>> 		    else /* 4k base page */
>> -			    hugepte_shift = PUD_SHIFT;
>> +			    hugepte_shift[psize] = PUD_SHIFT;
>> 		    break;
>> 		case PAGE_SHIFT_16G:
>> 		    /* 16G pages are always at PGD level */
>> -		    hugepte_shift = PGDIR_SHIFT;
>> +		    hugepte_shift[psize] = PGDIR_SHIFT;
>> 		    break;
>> 		}
>> -		hugepte_shift -= HPAGE_SHIFT;
>> +		hugepte_shift[psize] -= mmu_psize_defs[psize].shift;
>> 	} else
>> 		HPAGE_SHIFT = 0;
>> }
>> @@ -633,30 +713,15 @@ void set_huge_psize(int psize)
>> static int __init hugepage_setup_sz(char *str)
>> {
>> 	unsigned long long size;
>> -	int mmu_psize = -1;
>> +	int mmu_psize;
>> 	int shift;
>>
>> 	size = memparse(str, &str);
>>
>> 	shift = __ffs(size);
>> -	switch (shift) {
>> -#ifndef CONFIG_PPC_64K_PAGES
>> -	case PAGE_SHIFT_64K:
>> -		mmu_psize = MMU_PAGE_64K;
>> -		break;
>> -#endif
>> -	case PAGE_SHIFT_16M:
>> -		mmu_psize = MMU_PAGE_16M;
>> -		break;
>> -	case PAGE_SHIFT_16G:
>> -		mmu_psize = MMU_PAGE_16G;
>> -		break;
>> -	}
>> -
>> -	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
>> +	mmu_psize = shift_to_mmu_psize(shift);
>> +	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift)
>> 		set_huge_psize(mmu_psize);
>> -		huge_add_hstate(shift - PAGE_SHIFT);
>> -	}
>> 	else
>> 		printk(KERN_WARNING "Invalid huge page size 
>> 		specified(%llu)\n", size);
>>
>> @@ -671,16 +736,30 @@ static void zero_ctor(struct kmem_cache *cache, void 
>> *addr)
>>
>> static int __init hugetlbpage_init(void)
>> {
>> +	unsigned int psize;
>> 	if (!cpu_has_feature(CPU_FTR_16M_PAGE))
>> 		return -ENODEV;
>> -
>> -	huge_pgtable_cache = kmem_cache_create("hugepte_cache",
>> -					       HUGEPTE_TABLE_SIZE,
>> -					       HUGEPTE_TABLE_SIZE,
>> -					       0,
>> -					       zero_ctor);
>> -	if (! huge_pgtable_cache)
>> -		panic("hugetlbpage_init(): could not create hugepte 
>> cache\n");
>> +	/* Add supported huge page sizes.  Need to change HUGE_MAX_HSTATE
>> +	 * and adjust PTE_NONCACHE_NUM if the number of supported huge page
>> +	 * sizes changes.
>> +	 */
>> +	set_huge_psize(MMU_PAGE_16M);
>> +	set_huge_psize(MMU_PAGE_64K);
>> +	set_huge_psize(MMU_PAGE_16G);
>> +
>> +	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
>> +		if (mmu_huge_psizes[psize]) {
>> +			huge_pgtable_cache(psize) = kmem_cache_create(
>> +						HUGEPTE_CACHE_NAME(psize),
>> +						HUGEPTE_TABLE_SIZE(psize),
>> +						HUGEPTE_TABLE_SIZE(psize),
>> +						0,
>> +						zero_ctor);
>> +			if (!huge_pgtable_cache(psize))
>> +				panic("hugetlbpage_init(): could not create 
>> %s"\
>> +				      "\n", HUGEPTE_CACHE_NAME(psize));
>> +		}
>> +	}
>>
>> 	return 0;
>> }
>> diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
>> index c0f5cff..55588d5 100644
>> --- a/arch/powerpc/mm/init_64.c
>> +++ b/arch/powerpc/mm/init_64.c
>> @@ -151,10 +151,10 @@ static const char 
>> *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
>> };
>>
>> #ifdef CONFIG_HUGETLB_PAGE
>> -/* Hugepages need one extra cache, initialized in hugetlbpage.c.  We
>> - * can't put into the tables above, because HPAGE_SHIFT is not compile
>> - * time constant. */
>> -struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+1];
>> +/* Hugepages need an extra cache per hugepagesize, initialized in
>> + * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
>> + * is not compile time constant. */
>> +struct kmem_cache 
>> *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
>> #else
>> struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
>> #endif
>> diff --git a/arch/powerpc/mm/tlb_64.c b/arch/powerpc/mm/tlb_64.c
>> index e2d867c..8d79e16 100644
>> --- a/arch/powerpc/mm/tlb_64.c
>> +++ b/arch/powerpc/mm/tlb_64.c
>> @@ -150,7 +150,7 @@ void hpte_need_flush(struct mm_struct *mm, unsigned 
>> long addr,
>> 	 */
>> 	if (huge) {
>> #ifdef CONFIG_HUGETLB_PAGE
>> -		psize = mmu_huge_psize;
>> +		psize = get_slice_psize(mm, addr);;
>> #else
>> 		BUG();
>> 		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */
>> diff --git a/include/asm-powerpc/mmu-hash64.h 
>> b/include/asm-powerpc/mmu-hash64.h
>> index db1276a..63b0fa5 100644
>> --- a/include/asm-powerpc/mmu-hash64.h
>> +++ b/include/asm-powerpc/mmu-hash64.h
>> @@ -192,9 +192,9 @@ extern int mmu_ci_restrictions;
>>
>> #ifdef CONFIG_HUGETLB_PAGE
>> /*
>> - * The page size index of the huge pages for use by hugetlbfs
>> + * The page size indexes of the huge pages for use by hugetlbfs
>>  */
>> -extern int mmu_huge_psize;
>> +extern unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
>>
>> #endif /* CONFIG_HUGETLB_PAGE */
>>
>> diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h
>> index 67834ea..bdf453b 100644
>> --- a/include/asm-powerpc/page_64.h
>> +++ b/include/asm-powerpc/page_64.h
>> @@ -90,6 +90,7 @@ extern unsigned int HPAGE_SHIFT;
>> #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
>> #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
>> #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
>> +#define HUGE_MAX_HSTATE		3
>>
>> #endif /* __ASSEMBLY__ */
>>
>> diff --git a/include/asm-powerpc/pgalloc-64.h 
>> b/include/asm-powerpc/pgalloc-64.h
>> index 6898099..812a1d8 100644
>> --- a/include/asm-powerpc/pgalloc-64.h
>> +++ b/include/asm-powerpc/pgalloc-64.h
>> @@ -22,7 +22,7 @@ extern struct kmem_cache *pgtable_cache[];
>> #define PUD_CACHE_NUM		1
>> #define PMD_CACHE_NUM		1
>> #define HUGEPTE_CACHE_NUM	2
>> -#define PTE_NONCACHE_NUM	3  /* from GFP rather than kmem_cache */
>> +#define PTE_NONCACHE_NUM	7  /* from GFP rather than kmem_cache */
>>
>> static inline pgd_t *pgd_alloc(struct mm_struct *mm)
>> {
>> @@ -119,7 +119,7 @@ static inline void pte_free(struct mm_struct *mm, 
>> pgtable_t ptepage)
>> 	__free_page(ptepage);
>> }
>>
>> -#define PGF_CACHENUM_MASK	0x3
>> +#define PGF_CACHENUM_MASK	0x7
>>
>> typedef struct pgtable_free {
>> 	unsigned long val;
>>
>>     

Re: [PATCH 6/6] powerpc: support multiple huge page sizes

[Jon Tollefson]

Nick Piggin wrote:
> On Tue, May 13, 2008 at 12:25:27PM -0500, Jon Tollefson wrote:
>   
>> Instead of using the variable mmu_huge_psize to keep track of the huge
>> page size we use an array of MMU_PAGE_* values.  For each supported
>> huge page size we need to know the hugepte_shift value and have a
>> pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
>> functions so that they know which huge page size they should use.
>>
>> The hugepage sizes 16M and 64K are setup(if available on the
>> hardware) so that they don't have to be set on the boot cmd line in
>> order to use them.  The number of 16G pages have to be specified at
>> boot-time though (e.g. hugepagesz=16G hugepages=5).
>>
>>
>> Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
>> ---
>>
>> @@ -150,17 +191,25 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned 
>> long addr)
>> 	pud_t *pu;
>> 	pmd_t *pm;
>>
>> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
>> +	unsigned int psize;
>> +	unsigned int shift;
>> +	unsigned long sz;
>> +	struct hstate *hstate;
>> +	psize = get_slice_psize(mm, addr);
>> +	shift = mmu_psize_to_shift(psize);
>> +	sz = ((1UL) << shift);
>> +	hstate = size_to_hstate(sz);
>>
>> -	addr &= HPAGE_MASK;
>> +	addr &= hstate->mask;
>>
>> 	pg = pgd_offset(mm, addr);
>> 	if (!pgd_none(*pg)) {
>> 		pu = pud_offset(pg, addr);
>> 		if (!pud_none(*pu)) {
>> -			pm = hpmd_offset(pu, addr);
>> +			pm = hpmd_offset(pu, addr, hstate);
>> 			if (!pmd_none(*pm))
>> -				return hugepte_offset((hugepd_t *)pm, addr);
>> +				return hugepte_offset((hugepd_t *)pm, addr,
>> +						      hstate);
>> 		}
>> 	}
>>     
>
> Hi Jon,
>
> I just noticed in a few places like this, you might be doing more work
> than really needed to get the HPAGE_MASK.
>   
I would love to be able to simplify it.
> For a first-pass conversion, this is the right way to go (just manually
> replace hugepage constants with hstate-> equivalents). However in this
> case if you already know the page size, you should be able to work out
> the shift from there, I think? That way you can avoid the size_to_hstate
> call completely.
>   
Something like the following?

+	addr &= ~(sz - 1);

Is that faster then just pulling it out of hstate?
I still need to locate hstate, but I guess if the mask is calculated
this way the locate could be pushed further into the function so that it
isn't done if it isn't always needed.
> Anyway, just something to consider.
>
> Thanks,
> Nick
>   
Thank you for looking at the code.

Jon

>> @@ -173,16 +222,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
>> long addr, unsigned long sz
>> 	pud_t *pu;
>> 	pmd_t *pm;
>> 	hugepd_t *hpdp = NULL;
>> +	struct hstate *hstate;
>> +	unsigned int psize;
>> +	hstate = size_to_hstate(sz);
>>
>> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
>> +	psize = get_slice_psize(mm, addr);
>> +	BUG_ON(!mmu_huge_psizes[psize]);
>>
>> -	addr &= HPAGE_MASK;
>> +	addr &= hstate->mask;
>>
>> 	pg = pgd_offset(mm, addr);
>> 	pu = pud_alloc(mm, pg, addr);
>>
>> 	if (pu) {
>> -		pm = hpmd_alloc(mm, pu, addr);
>> +		pm = hpmd_alloc(mm, pu, addr, hstate);
>> 		if (pm)
>> 			hpdp = (hugepd_t *)pm;
>> 	}
>> @@ -190,10 +243,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
>> long addr, unsigned long sz
>> 	if (! hpdp)
>> 		return NULL;
>>
>> -	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
>> +	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize))
>> 		return NULL;
>>
>> -	return hugepte_offset(hpdp, addr);
>> +	return hugepte_offset(hpdp, addr, hstate);
>> }
>>
>> int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
>> @@ -201,19 +254,22 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned 
>> long *addr, pte_t *ptep)
>> 	return 0;
>> }
>>
>> -static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
>> +static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp,
>> +			       unsigned int psize)
>> {
>> 	pte_t *hugepte = hugepd_page(*hpdp);
>>
>> 	hpdp->pd = 0;
>> 	tlb->need_flush = 1;
>> -	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
>> +	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte,
>> +						 HUGEPTE_CACHE_NUM+psize-1,
>> 						 PGF_CACHENUM_MASK));
>> }
>>
>> static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
>> 				   unsigned long addr, unsigned long end,
>> -				   unsigned long floor, unsigned long 
>> ceiling)
>> +				   unsigned long floor, unsigned long 
>> ceiling,
>> +				   unsigned int psize)
>> {
>> 	pmd_t *pmd;
>> 	unsigned long next;
>> @@ -225,7 +281,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather 
>> *tlb, pud_t *pud,
>> 		next = pmd_addr_end(addr, end);
>> 		if (pmd_none(*pmd))
>> 			continue;
>> -		free_hugepte_range(tlb, (hugepd_t *)pmd);
>> +		free_hugepte_range(tlb, (hugepd_t *)pmd, psize);
>> 	} while (pmd++, addr = next, addr != end);
>>
>> 	start &= PUD_MASK;
>> @@ -251,6 +307,9 @@ static void hugetlb_free_pud_range(struct mmu_gather 
>> *tlb, pgd_t *pgd,
>> 	pud_t *pud;
>> 	unsigned long next;
>> 	unsigned long start;
>> +	unsigned int shift;
>> +	unsigned int psize = get_slice_psize(tlb->mm, addr);
>> +	shift = mmu_psize_to_shift(psize);
>>
>> 	start = addr;
>> 	pud = pud_offset(pgd, addr);
>> @@ -259,16 +318,18 @@ static void hugetlb_free_pud_range(struct mmu_gather 
>> *tlb, pgd_t *pgd,
>> #ifdef CONFIG_PPC_64K_PAGES
>> 		if (pud_none_or_clear_bad(pud))
>> 			continue;
>> -		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
>> +		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling,
>> +				       psize);
>> #else
>> -		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
>> +		if (shift == PAGE_SHIFT_64K) {
>> 			if (pud_none_or_clear_bad(pud))
>> 				continue;
>> -			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, 
>> ceiling);
>> +			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
>> +					       ceiling, psize);
>> 		} else {
>> 			if (pud_none(*pud))
>> 				continue;
>> -			free_hugepte_range(tlb, (hugepd_t *)pud);
>> +			free_hugepte_range(tlb, (hugepd_t *)pud, psize);
>> 		}
>> #endif
>> 	} while (pud++, addr = next, addr != end);
>> @@ -336,27 +397,29 @@ void hugetlb_free_pgd_range(struct mmu_gather **tlb,
>> 	 * now has no other vmas using it, so can be freed, we don't
>> 	 * bother to round floor or end up - the tests don't need that.
>> 	 */
>> +	unsigned int psize = get_slice_psize((*tlb)->mm, addr);
>>
>> -	addr &= HUGEPD_MASK;
>> +	addr &= HUGEPD_MASK(psize);
>> 	if (addr < floor) {
>> -		addr += HUGEPD_SIZE;
>> +		addr += HUGEPD_SIZE(psize);
>> 		if (!addr)
>> 			return;
>> 	}
>> 	if (ceiling) {
>> -		ceiling &= HUGEPD_MASK;
>> +		ceiling &= HUGEPD_MASK(psize);
>> 		if (!ceiling)
>> 			return;
>> 	}
>> 	if (end - 1 > ceiling - 1)
>> -		end -= HUGEPD_SIZE;
>> +		end -= HUGEPD_SIZE(psize);
>> 	if (addr > end - 1)
>> 		return;
>>
>> 	start = addr;
>> 	pgd = pgd_offset((*tlb)->mm, addr);
>> 	do {
>> -		BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
>> +		psize = get_slice_psize((*tlb)->mm, addr);
>> +		BUG_ON(!mmu_huge_psizes[psize]);
>> 		next = pgd_addr_end(addr, end);
>> 		if (pgd_none_or_clear_bad(pgd))
>> 			continue;
>> @@ -373,7 +436,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned 
>> long addr,
>> 		 * necessary anymore if we make hpte_need_flush() get the
>> 		 * page size from the slices
>> 		 */
>> -		pte_update(mm, addr & HPAGE_MASK, ptep, ~0UL, 1);
>> +		unsigned int psize = get_slice_psize(mm, addr);
>> +		unsigned int shift = mmu_psize_to_shift(psize);
>> +		unsigned long sz;
>> +		sz = ((1UL) << shift);
>> +		struct hstate *hstate = size_to_hstate(sz);
>> +		pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1);
>> 	}
>> 	*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
>> }
>> @@ -390,14 +458,19 @@ follow_huge_addr(struct mm_struct *mm, unsigned long 
>> address, int write)
>> {
>> 	pte_t *ptep;
>> 	struct page *page;
>> +	unsigned int mmu_psize = get_slice_psize(mm, address);
>>
>> -	if (get_slice_psize(mm, address) != mmu_huge_psize)
>> +	/* Verify it is a huge page else bail. */
>> +	if (!mmu_huge_psizes[mmu_psize])
>> 		return ERR_PTR(-EINVAL);
>>
>> 	ptep = huge_pte_offset(mm, address);
>> 	page = pte_page(*ptep);
>> -	if (page)
>> -		page += (address % HPAGE_SIZE) / PAGE_SIZE;
>> +	if (page) {
>> +		unsigned int shift = mmu_psize_to_shift(mmu_psize);
>> +		unsigned long sz = ((1UL) << shift);
>> +		page += (address % sz) / PAGE_SIZE;
>> +	}
>>
>> 	return page;
>> }
>> @@ -425,15 +498,16 @@ unsigned long hugetlb_get_unmapped_area(struct file 
>> *file, unsigned long addr,
>> 					unsigned long len, unsigned long 
>> 					pgoff,
>> 					unsigned long flags)
>> {
>> -	return slice_get_unmapped_area(addr, len, flags,
>> -				       mmu_huge_psize, 1, 0);
>> +	struct hstate *hstate = hstate_file(file);
>> +	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
>> +	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
>> }
>>
>> /*
>>  * Called by asm hashtable.S for doing lazy icache flush
>>  */
>> static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
>> -						  pte_t pte, int trap)
>> +					pte_t pte, int trap, unsigned long 
>> sz)
>> {
>> 	struct page *page;
>> 	int i;
>> @@ -446,7 +520,7 @@ static unsigned int 
>> hash_huge_page_do_lazy_icache(unsigned long rflags,
>> 	/* page is dirty */
>> 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
>> 		if (trap == 0x400) {
>> -			for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
>> +			for (i = 0; i < (sz / PAGE_SIZE); i++)
>> 				__flush_dcache_icache(page_address(page+i));
>> 			set_bit(PG_arch_1, &page->flags);
>> 		} else {
>> @@ -466,7 +540,12 @@ int hash_huge_page(struct mm_struct *mm, unsigned long 
>> access,
>> 	long slot;
>> 	int err = 1;
>> 	int ssize = user_segment_size(ea);
>> +	unsigned int mmu_psize;
>> +	int shift;
>> +	mmu_psize = get_slice_psize(mm, ea);
>>
>> +	if(!mmu_huge_psizes[mmu_psize])
>> +		goto out;
>> 	ptep = huge_pte_offset(mm, ea);
>>
>> 	/* Search the Linux page table for a match with va */
>> @@ -510,30 +589,32 @@ int hash_huge_page(struct mm_struct *mm, unsigned 
>> long access,
>> 	rflags = 0x2 | (!(new_pte & _PAGE_RW));
>>  	/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
>> 	rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
>> +	shift = mmu_psize_to_shift(mmu_psize);
>> +	unsigned long sz = ((1UL) << shift);
>> 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
>> 		/* No CPU has hugepages but lacks no execute, so we
>> 		 * don't need to worry about that case */
>> 		rflags = hash_huge_page_do_lazy_icache(rflags, 
>> 		__pte(old_pte),
>> -						       trap);
>> +						       trap, sz);
>>
>> 	/* Check if pte already has an hpte (case 2) */
>> 	if (unlikely(old_pte & _PAGE_HASHPTE)) {
>> 		/* There MIGHT be an HPTE for this pte */
>> 		unsigned long hash, slot;
>>
>> -		hash = hpt_hash(va, HPAGE_SHIFT, ssize);
>> +		hash = hpt_hash(va, shift, ssize);
>> 		if (old_pte & _PAGE_F_SECOND)
>> 			hash = ~hash;
>> 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
>> 		slot += (old_pte & _PAGE_F_GIX) >> 12;
>>
>> -		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
>> +		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize,
>> 					 ssize, local) == -1)
>> 			old_pte &= ~_PAGE_HPTEFLAGS;
>> 	}
>>
>> 	if (likely(!(old_pte & _PAGE_HASHPTE))) {
>> -		unsigned long hash = hpt_hash(va, HPAGE_SHIFT, ssize);
>> +		unsigned long hash = hpt_hash(va, shift, ssize);
>> 		unsigned long hpte_group;
>>
>> 		pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
>> @@ -552,7 +633,7 @@ repeat:
>>
>> 		/* Insert into the hash table, primary slot */
>> 		slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
>> -					  mmu_huge_psize, ssize);
>> +					  mmu_psize, ssize);
>>
>> 		/* Primary is full, try the secondary */
>> 		if (unlikely(slot == -1)) {
>> @@ -560,7 +641,7 @@ repeat:
>> 				      HPTES_PER_GROUP) & ~0x7UL; 
>> 			slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
>> 						  HPTE_V_SECONDARY,
>> -						  mmu_huge_psize, ssize);
>> +						  mmu_psize, ssize);
>> 			if (slot == -1) {
>> 				if (mftb() & 0x1)
>> 					hpte_group = ((hash & 
>> 					htab_hash_mask) *
>> @@ -597,35 +678,34 @@ void set_huge_psize(int psize)
>> 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
>> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
>> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
>> -		/* Return if huge page size is the same as the
>> -		 * base page size. */
>> -		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
>> +		/* Return if huge page size has already been setup or is the
>> +		 * same as the base page size. */
>> +		if (mmu_huge_psizes[psize] ||
>> +		   mmu_psize_defs[psize].shift == PAGE_SHIFT)
>> 			return;
>> +		huge_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT);
>>
>> -		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
>> -		mmu_huge_psize = psize;
>> -
>> -		switch (HPAGE_SHIFT) {
>> +		switch (mmu_psize_defs[psize].shift) {
>> 		case PAGE_SHIFT_64K:
>> 		    /* We only allow 64k hpages with 4k base page,
>> 		     * which was checked above, and always put them
>> 		     * at the PMD */
>> -		    hugepte_shift = PMD_SHIFT;
>> +		    hugepte_shift[psize] = PMD_SHIFT;
>> 		    break;
>> 		case PAGE_SHIFT_16M:
>> 		    /* 16M pages can be at two different levels
>> 		     * of pagestables based on base page size */
>> 		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
>> -			    hugepte_shift = PMD_SHIFT;
>> +			    hugepte_shift[psize] = PMD_SHIFT;
>> 		    else /* 4k base page */
>> -			    hugepte_shift = PUD_SHIFT;
>> +			    hugepte_shift[psize] = PUD_SHIFT;
>> 		    break;
>> 		case PAGE_SHIFT_16G:
>> 		    /* 16G pages are always at PGD level */
>> -		    hugepte_shift = PGDIR_SHIFT;
>> +		    hugepte_shift[psize] = PGDIR_SHIFT;
>> 		    break;
>> 		}
>> -		hugepte_shift -= HPAGE_SHIFT;
>> +		hugepte_shift[psize] -= mmu_psize_defs[psize].shift;
>> 	} else
>> 		HPAGE_SHIFT = 0;
>> }
>> @@ -633,30 +713,15 @@ void set_huge_psize(int psize)
>> static int __init hugepage_setup_sz(char *str)
>> {
>> 	unsigned long long size;
>> -	int mmu_psize = -1;
>> +	int mmu_psize;
>> 	int shift;
>>
>> 	size = memparse(str, &str);
>>
>> 	shift = __ffs(size);
>> -	switch (shift) {
>> -#ifndef CONFIG_PPC_64K_PAGES
>> -	case PAGE_SHIFT_64K:
>> -		mmu_psize = MMU_PAGE_64K;
>> -		break;
>> -#endif
>> -	case PAGE_SHIFT_16M:
>> -		mmu_psize = MMU_PAGE_16M;
>> -		break;
>> -	case PAGE_SHIFT_16G:
>> -		mmu_psize = MMU_PAGE_16G;
>> -		break;
>> -	}
>> -
>> -	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
>> +	mmu_psize = shift_to_mmu_psize(shift);
>> +	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift)
>> 		set_huge_psize(mmu_psize);
>> -		huge_add_hstate(shift - PAGE_SHIFT);
>> -	}
>> 	else
>> 		printk(KERN_WARNING "Invalid huge page size 
>> 		specified(%llu)\n", size);
>>
>> @@ -671,16 +736,30 @@ static void zero_ctor(struct kmem_cache *cache, void 
>> *addr)
>>
>> static int __init hugetlbpage_init(void)
>> {
>> +	unsigned int psize;
>> 	if (!cpu_has_feature(CPU_FTR_16M_PAGE))
>> 		return -ENODEV;
>> -
>> -	huge_pgtable_cache = kmem_cache_create("hugepte_cache",
>> -					       HUGEPTE_TABLE_SIZE,
>> -					       HUGEPTE_TABLE_SIZE,
>> -					       0,
>> -					       zero_ctor);
>> -	if (! huge_pgtable_cache)
>> -		panic("hugetlbpage_init(): could not create hugepte 
>> cache\n");
>> +	/* Add supported huge page sizes.  Need to change HUGE_MAX_HSTATE
>> +	 * and adjust PTE_NONCACHE_NUM if the number of supported huge page
>> +	 * sizes changes.
>> +	 */
>> +	set_huge_psize(MMU_PAGE_16M);
>> +	set_huge_psize(MMU_PAGE_64K);
>> +	set_huge_psize(MMU_PAGE_16G);
>> +
>> +	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
>> +		if (mmu_huge_psizes[psize]) {
>> +			huge_pgtable_cache(psize) = kmem_cache_create(
>> +						HUGEPTE_CACHE_NAME(psize),
>> +						HUGEPTE_TABLE_SIZE(psize),
>> +						HUGEPTE_TABLE_SIZE(psize),
>> +						0,
>> +						zero_ctor);
>> +			if (!huge_pgtable_cache(psize))
>> +				panic("hugetlbpage_init(): could not create 
>> %s"\
>> +				      "\n", HUGEPTE_CACHE_NAME(psize));
>> +		}
>> +	}
>>
>> 	return 0;
>> }
>> diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
>> index c0f5cff..55588d5 100644
>> --- a/arch/powerpc/mm/init_64.c
>> +++ b/arch/powerpc/mm/init_64.c
>> @@ -151,10 +151,10 @@ static const char 
>> *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
>> };
>>
>> #ifdef CONFIG_HUGETLB_PAGE
>> -/* Hugepages need one extra cache, initialized in hugetlbpage.c.  We
>> - * can't put into the tables above, because HPAGE_SHIFT is not compile
>> - * time constant. */
>> -struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+1];
>> +/* Hugepages need an extra cache per hugepagesize, initialized in
>> + * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
>> + * is not compile time constant. */
>> +struct kmem_cache 
>> *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
>> #else
>> struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
>> #endif
>> diff --git a/arch/powerpc/mm/tlb_64.c b/arch/powerpc/mm/tlb_64.c
>> index e2d867c..8d79e16 100644
>> --- a/arch/powerpc/mm/tlb_64.c
>> +++ b/arch/powerpc/mm/tlb_64.c
>> @@ -150,7 +150,7 @@ void hpte_need_flush(struct mm_struct *mm, unsigned 
>> long addr,
>> 	 */
>> 	if (huge) {
>> #ifdef CONFIG_HUGETLB_PAGE
>> -		psize = mmu_huge_psize;
>> +		psize = get_slice_psize(mm, addr);;
>> #else
>> 		BUG();
>> 		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */
>> diff --git a/include/asm-powerpc/mmu-hash64.h 
>> b/include/asm-powerpc/mmu-hash64.h
>> index db1276a..63b0fa5 100644
>> --- a/include/asm-powerpc/mmu-hash64.h
>> +++ b/include/asm-powerpc/mmu-hash64.h
>> @@ -192,9 +192,9 @@ extern int mmu_ci_restrictions;
>>
>> #ifdef CONFIG_HUGETLB_PAGE
>> /*
>> - * The page size index of the huge pages for use by hugetlbfs
>> + * The page size indexes of the huge pages for use by hugetlbfs
>>  */
>> -extern int mmu_huge_psize;
>> +extern unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
>>
>> #endif /* CONFIG_HUGETLB_PAGE */
>>
>> diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h
>> index 67834ea..bdf453b 100644
>> --- a/include/asm-powerpc/page_64.h
>> +++ b/include/asm-powerpc/page_64.h
>> @@ -90,6 +90,7 @@ extern unsigned int HPAGE_SHIFT;
>> #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
>> #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
>> #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
>> +#define HUGE_MAX_HSTATE		3
>>
>> #endif /* __ASSEMBLY__ */
>>
>> diff --git a/include/asm-powerpc/pgalloc-64.h 
>> b/include/asm-powerpc/pgalloc-64.h
>> index 6898099..812a1d8 100644
>> --- a/include/asm-powerpc/pgalloc-64.h
>> +++ b/include/asm-powerpc/pgalloc-64.h
>> @@ -22,7 +22,7 @@ extern struct kmem_cache *pgtable_cache[];
>> #define PUD_CACHE_NUM		1
>> #define PMD_CACHE_NUM		1
>> #define HUGEPTE_CACHE_NUM	2
>> -#define PTE_NONCACHE_NUM	3  /* from GFP rather than kmem_cache */
>> +#define PTE_NONCACHE_NUM	7  /* from GFP rather than kmem_cache */
>>
>> static inline pgd_t *pgd_alloc(struct mm_struct *mm)
>> {
>> @@ -119,7 +119,7 @@ static inline void pte_free(struct mm_struct *mm, 
>> pgtable_t ptepage)
>> 	__free_page(ptepage);
>> }
>>
>> -#define PGF_CACHENUM_MASK	0x3
>> +#define PGF_CACHENUM_MASK	0x7
>>
>> typedef struct pgtable_free {
>> 	unsigned long val;
>>
>>     

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Re: [PATCH 6/6] powerpc: support multiple huge page sizes

[Jon Tollefson]

Nick Piggin wrote:
> On Tue, May 13, 2008 at 12:25:27PM -0500, Jon Tollefson wrote:
>   
>> Instead of using the variable mmu_huge_psize to keep track of the huge
>> page size we use an array of MMU_PAGE_* values.  For each supported
>> huge page size we need to know the hugepte_shift value and have a
>> pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
>> functions so that they know which huge page size they should use.
>>
>> The hugepage sizes 16M and 64K are setup(if available on the
>> hardware) so that they don't have to be set on the boot cmd line in
>> order to use them.  The number of 16G pages have to be specified at
>> boot-time though (e.g. hugepagesz=16G hugepages=5).
>>
>>
>> Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
>> ---
>>
>> @@ -150,17 +191,25 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned 
>> long addr)
>> 	pud_t *pu;
>> 	pmd_t *pm;
>>
>> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
>> +	unsigned int psize;
>> +	unsigned int shift;
>> +	unsigned long sz;
>> +	struct hstate *hstate;
>> +	psize = get_slice_psize(mm, addr);
>> +	shift = mmu_psize_to_shift(psize);
>> +	sz = ((1UL) << shift);
>> +	hstate = size_to_hstate(sz);
>>
>> -	addr &= HPAGE_MASK;
>> +	addr &= hstate->mask;
>>
>> 	pg = pgd_offset(mm, addr);
>> 	if (!pgd_none(*pg)) {
>> 		pu = pud_offset(pg, addr);
>> 		if (!pud_none(*pu)) {
>> -			pm = hpmd_offset(pu, addr);
>> +			pm = hpmd_offset(pu, addr, hstate);
>> 			if (!pmd_none(*pm))
>> -				return hugepte_offset((hugepd_t *)pm, addr);
>> +				return hugepte_offset((hugepd_t *)pm, addr,
>> +						      hstate);
>> 		}
>> 	}
>>     
>
> Hi Jon,
>
> I just noticed in a few places like this, you might be doing more work
> than really needed to get the HPAGE_MASK.
>   
I would love to be able to simplify it.
> For a first-pass conversion, this is the right way to go (just manually
> replace hugepage constants with hstate-> equivalents). However in this
> case if you already know the page size, you should be able to work out
> the shift from there, I think? That way you can avoid the size_to_hstate
> call completely.
>   
Something like the following?

+	addr &= ~(sz - 1);

Is that faster then just pulling it out of hstate?
I still need to locate hstate, but I guess if the mask is calculated
this way the locate could be pushed further into the function so that it
isn't done if it isn't always needed.
> Anyway, just something to consider.
>
> Thanks,
> Nick
>   
Thank you for looking at the code.

Jon

>> @@ -173,16 +222,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
>> long addr, unsigned long sz
>> 	pud_t *pu;
>> 	pmd_t *pm;
>> 	hugepd_t *hpdp = NULL;
>> +	struct hstate *hstate;
>> +	unsigned int psize;
>> +	hstate = size_to_hstate(sz);
>>
>> -	BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
>> +	psize = get_slice_psize(mm, addr);
>> +	BUG_ON(!mmu_huge_psizes[psize]);
>>
>> -	addr &= HPAGE_MASK;
>> +	addr &= hstate->mask;
>>
>> 	pg = pgd_offset(mm, addr);
>> 	pu = pud_alloc(mm, pg, addr);
>>
>> 	if (pu) {
>> -		pm = hpmd_alloc(mm, pu, addr);
>> +		pm = hpmd_alloc(mm, pu, addr, hstate);
>> 		if (pm)
>> 			hpdp = (hugepd_t *)pm;
>> 	}
>> @@ -190,10 +243,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned 
>> long addr, unsigned long sz
>> 	if (! hpdp)
>> 		return NULL;
>>
>> -	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
>> +	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize))
>> 		return NULL;
>>
>> -	return hugepte_offset(hpdp, addr);
>> +	return hugepte_offset(hpdp, addr, hstate);
>> }
>>
>> int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
>> @@ -201,19 +254,22 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned 
>> long *addr, pte_t *ptep)
>> 	return 0;
>> }
>>
>> -static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
>> +static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp,
>> +			       unsigned int psize)
>> {
>> 	pte_t *hugepte = hugepd_page(*hpdp);
>>
>> 	hpdp->pd = 0;
>> 	tlb->need_flush = 1;
>> -	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
>> +	pgtable_free_tlb(tlb, pgtable_free_cache(hugepte,
>> +						 HUGEPTE_CACHE_NUM+psize-1,
>> 						 PGF_CACHENUM_MASK));
>> }
>>
>> static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
>> 				   unsigned long addr, unsigned long end,
>> -				   unsigned long floor, unsigned long 
>> ceiling)
>> +				   unsigned long floor, unsigned long 
>> ceiling,
>> +				   unsigned int psize)
>> {
>> 	pmd_t *pmd;
>> 	unsigned long next;
>> @@ -225,7 +281,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather 
>> *tlb, pud_t *pud,
>> 		next = pmd_addr_end(addr, end);
>> 		if (pmd_none(*pmd))
>> 			continue;
>> -		free_hugepte_range(tlb, (hugepd_t *)pmd);
>> +		free_hugepte_range(tlb, (hugepd_t *)pmd, psize);
>> 	} while (pmd++, addr = next, addr != end);
>>
>> 	start &= PUD_MASK;
>> @@ -251,6 +307,9 @@ static void hugetlb_free_pud_range(struct mmu_gather 
>> *tlb, pgd_t *pgd,
>> 	pud_t *pud;
>> 	unsigned long next;
>> 	unsigned long start;
>> +	unsigned int shift;
>> +	unsigned int psize = get_slice_psize(tlb->mm, addr);
>> +	shift = mmu_psize_to_shift(psize);
>>
>> 	start = addr;
>> 	pud = pud_offset(pgd, addr);
>> @@ -259,16 +318,18 @@ static void hugetlb_free_pud_range(struct mmu_gather 
>> *tlb, pgd_t *pgd,
>> #ifdef CONFIG_PPC_64K_PAGES
>> 		if (pud_none_or_clear_bad(pud))
>> 			continue;
>> -		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
>> +		hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling,
>> +				       psize);
>> #else
>> -		if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
>> +		if (shift == PAGE_SHIFT_64K) {
>> 			if (pud_none_or_clear_bad(pud))
>> 				continue;
>> -			hugetlb_free_pmd_range(tlb, pud, addr, next, floor, 
>> ceiling);
>> +			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
>> +					       ceiling, psize);
>> 		} else {
>> 			if (pud_none(*pud))
>> 				continue;
>> -			free_hugepte_range(tlb, (hugepd_t *)pud);
>> +			free_hugepte_range(tlb, (hugepd_t *)pud, psize);
>> 		}
>> #endif
>> 	} while (pud++, addr = next, addr != end);
>> @@ -336,27 +397,29 @@ void hugetlb_free_pgd_range(struct mmu_gather **tlb,
>> 	 * now has no other vmas using it, so can be freed, we don't
>> 	 * bother to round floor or end up - the tests don't need that.
>> 	 */
>> +	unsigned int psize = get_slice_psize((*tlb)->mm, addr);
>>
>> -	addr &= HUGEPD_MASK;
>> +	addr &= HUGEPD_MASK(psize);
>> 	if (addr < floor) {
>> -		addr += HUGEPD_SIZE;
>> +		addr += HUGEPD_SIZE(psize);
>> 		if (!addr)
>> 			return;
>> 	}
>> 	if (ceiling) {
>> -		ceiling &= HUGEPD_MASK;
>> +		ceiling &= HUGEPD_MASK(psize);
>> 		if (!ceiling)
>> 			return;
>> 	}
>> 	if (end - 1 > ceiling - 1)
>> -		end -= HUGEPD_SIZE;
>> +		end -= HUGEPD_SIZE(psize);
>> 	if (addr > end - 1)
>> 		return;
>>
>> 	start = addr;
>> 	pgd = pgd_offset((*tlb)->mm, addr);
>> 	do {
>> -		BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
>> +		psize = get_slice_psize((*tlb)->mm, addr);
>> +		BUG_ON(!mmu_huge_psizes[psize]);
>> 		next = pgd_addr_end(addr, end);
>> 		if (pgd_none_or_clear_bad(pgd))
>> 			continue;
>> @@ -373,7 +436,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned 
>> long addr,
>> 		 * necessary anymore if we make hpte_need_flush() get the
>> 		 * page size from the slices
>> 		 */
>> -		pte_update(mm, addr & HPAGE_MASK, ptep, ~0UL, 1);
>> +		unsigned int psize = get_slice_psize(mm, addr);
>> +		unsigned int shift = mmu_psize_to_shift(psize);
>> +		unsigned long sz;
>> +		sz = ((1UL) << shift);
>> +		struct hstate *hstate = size_to_hstate(sz);
>> +		pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1);
>> 	}
>> 	*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
>> }
>> @@ -390,14 +458,19 @@ follow_huge_addr(struct mm_struct *mm, unsigned long 
>> address, int write)
>> {
>> 	pte_t *ptep;
>> 	struct page *page;
>> +	unsigned int mmu_psize = get_slice_psize(mm, address);
>>
>> -	if (get_slice_psize(mm, address) != mmu_huge_psize)
>> +	/* Verify it is a huge page else bail. */
>> +	if (!mmu_huge_psizes[mmu_psize])
>> 		return ERR_PTR(-EINVAL);
>>
>> 	ptep = huge_pte_offset(mm, address);
>> 	page = pte_page(*ptep);
>> -	if (page)
>> -		page += (address % HPAGE_SIZE) / PAGE_SIZE;
>> +	if (page) {
>> +		unsigned int shift = mmu_psize_to_shift(mmu_psize);
>> +		unsigned long sz = ((1UL) << shift);
>> +		page += (address % sz) / PAGE_SIZE;
>> +	}
>>
>> 	return page;
>> }
>> @@ -425,15 +498,16 @@ unsigned long hugetlb_get_unmapped_area(struct file 
>> *file, unsigned long addr,
>> 					unsigned long len, unsigned long 
>> 					pgoff,
>> 					unsigned long flags)
>> {
>> -	return slice_get_unmapped_area(addr, len, flags,
>> -				       mmu_huge_psize, 1, 0);
>> +	struct hstate *hstate = hstate_file(file);
>> +	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
>> +	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
>> }
>>
>> /*
>>  * Called by asm hashtable.S for doing lazy icache flush
>>  */
>> static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
>> -						  pte_t pte, int trap)
>> +					pte_t pte, int trap, unsigned long 
>> sz)
>> {
>> 	struct page *page;
>> 	int i;
>> @@ -446,7 +520,7 @@ static unsigned int 
>> hash_huge_page_do_lazy_icache(unsigned long rflags,
>> 	/* page is dirty */
>> 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
>> 		if (trap == 0x400) {
>> -			for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
>> +			for (i = 0; i < (sz / PAGE_SIZE); i++)
>> 				__flush_dcache_icache(page_address(page+i));
>> 			set_bit(PG_arch_1, &page->flags);
>> 		} else {
>> @@ -466,7 +540,12 @@ int hash_huge_page(struct mm_struct *mm, unsigned long 
>> access,
>> 	long slot;
>> 	int err = 1;
>> 	int ssize = user_segment_size(ea);
>> +	unsigned int mmu_psize;
>> +	int shift;
>> +	mmu_psize = get_slice_psize(mm, ea);
>>
>> +	if(!mmu_huge_psizes[mmu_psize])
>> +		goto out;
>> 	ptep = huge_pte_offset(mm, ea);
>>
>> 	/* Search the Linux page table for a match with va */
>> @@ -510,30 +589,32 @@ int hash_huge_page(struct mm_struct *mm, unsigned 
>> long access,
>> 	rflags = 0x2 | (!(new_pte & _PAGE_RW));
>>  	/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
>> 	rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
>> +	shift = mmu_psize_to_shift(mmu_psize);
>> +	unsigned long sz = ((1UL) << shift);
>> 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
>> 		/* No CPU has hugepages but lacks no execute, so we
>> 		 * don't need to worry about that case */
>> 		rflags = hash_huge_page_do_lazy_icache(rflags, 
>> 		__pte(old_pte),
>> -						       trap);
>> +						       trap, sz);
>>
>> 	/* Check if pte already has an hpte (case 2) */
>> 	if (unlikely(old_pte & _PAGE_HASHPTE)) {
>> 		/* There MIGHT be an HPTE for this pte */
>> 		unsigned long hash, slot;
>>
>> -		hash = hpt_hash(va, HPAGE_SHIFT, ssize);
>> +		hash = hpt_hash(va, shift, ssize);
>> 		if (old_pte & _PAGE_F_SECOND)
>> 			hash = ~hash;
>> 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
>> 		slot += (old_pte & _PAGE_F_GIX) >> 12;
>>
>> -		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
>> +		if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize,
>> 					 ssize, local) == -1)
>> 			old_pte &= ~_PAGE_HPTEFLAGS;
>> 	}
>>
>> 	if (likely(!(old_pte & _PAGE_HASHPTE))) {
>> -		unsigned long hash = hpt_hash(va, HPAGE_SHIFT, ssize);
>> +		unsigned long hash = hpt_hash(va, shift, ssize);
>> 		unsigned long hpte_group;
>>
>> 		pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
>> @@ -552,7 +633,7 @@ repeat:
>>
>> 		/* Insert into the hash table, primary slot */
>> 		slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
>> -					  mmu_huge_psize, ssize);
>> +					  mmu_psize, ssize);
>>
>> 		/* Primary is full, try the secondary */
>> 		if (unlikely(slot == -1)) {
>> @@ -560,7 +641,7 @@ repeat:
>> 				      HPTES_PER_GROUP) & ~0x7UL; 
>> 			slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
>> 						  HPTE_V_SECONDARY,
>> -						  mmu_huge_psize, ssize);
>> +						  mmu_psize, ssize);
>> 			if (slot == -1) {
>> 				if (mftb() & 0x1)
>> 					hpte_group = ((hash & 
>> 					htab_hash_mask) *
>> @@ -597,35 +678,34 @@ void set_huge_psize(int psize)
>> 		(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
>> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
>> 		 mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
>> -		/* Return if huge page size is the same as the
>> -		 * base page size. */
>> -		if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
>> +		/* Return if huge page size has already been setup or is the
>> +		 * same as the base page size. */
>> +		if (mmu_huge_psizes[psize] ||
>> +		   mmu_psize_defs[psize].shift == PAGE_SHIFT)
>> 			return;
>> +		huge_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT);
>>
>> -		HPAGE_SHIFT = mmu_psize_defs[psize].shift;
>> -		mmu_huge_psize = psize;
>> -
>> -		switch (HPAGE_SHIFT) {
>> +		switch (mmu_psize_defs[psize].shift) {
>> 		case PAGE_SHIFT_64K:
>> 		    /* We only allow 64k hpages with 4k base page,
>> 		     * which was checked above, and always put them
>> 		     * at the PMD */
>> -		    hugepte_shift = PMD_SHIFT;
>> +		    hugepte_shift[psize] = PMD_SHIFT;
>> 		    break;
>> 		case PAGE_SHIFT_16M:
>> 		    /* 16M pages can be at two different levels
>> 		     * of pagestables based on base page size */
>> 		    if (PAGE_SHIFT == PAGE_SHIFT_64K)
>> -			    hugepte_shift = PMD_SHIFT;
>> +			    hugepte_shift[psize] = PMD_SHIFT;
>> 		    else /* 4k base page */
>> -			    hugepte_shift = PUD_SHIFT;
>> +			    hugepte_shift[psize] = PUD_SHIFT;
>> 		    break;
>> 		case PAGE_SHIFT_16G:
>> 		    /* 16G pages are always at PGD level */
>> -		    hugepte_shift = PGDIR_SHIFT;
>> +		    hugepte_shift[psize] = PGDIR_SHIFT;
>> 		    break;
>> 		}
>> -		hugepte_shift -= HPAGE_SHIFT;
>> +		hugepte_shift[psize] -= mmu_psize_defs[psize].shift;
>> 	} else
>> 		HPAGE_SHIFT = 0;
>> }
>> @@ -633,30 +713,15 @@ void set_huge_psize(int psize)
>> static int __init hugepage_setup_sz(char *str)
>> {
>> 	unsigned long long size;
>> -	int mmu_psize = -1;
>> +	int mmu_psize;
>> 	int shift;
>>
>> 	size = memparse(str, &str);
>>
>> 	shift = __ffs(size);
>> -	switch (shift) {
>> -#ifndef CONFIG_PPC_64K_PAGES
>> -	case PAGE_SHIFT_64K:
>> -		mmu_psize = MMU_PAGE_64K;
>> -		break;
>> -#endif
>> -	case PAGE_SHIFT_16M:
>> -		mmu_psize = MMU_PAGE_16M;
>> -		break;
>> -	case PAGE_SHIFT_16G:
>> -		mmu_psize = MMU_PAGE_16G;
>> -		break;
>> -	}
>> -
>> -	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
>> +	mmu_psize = shift_to_mmu_psize(shift);
>> +	if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift)
>> 		set_huge_psize(mmu_psize);
>> -		huge_add_hstate(shift - PAGE_SHIFT);
>> -	}
>> 	else
>> 		printk(KERN_WARNING "Invalid huge page size 
>> 		specified(%llu)\n", size);
>>
>> @@ -671,16 +736,30 @@ static void zero_ctor(struct kmem_cache *cache, void 
>> *addr)
>>
>> static int __init hugetlbpage_init(void)
>> {
>> +	unsigned int psize;
>> 	if (!cpu_has_feature(CPU_FTR_16M_PAGE))
>> 		return -ENODEV;
>> -
>> -	huge_pgtable_cache = kmem_cache_create("hugepte_cache",
>> -					       HUGEPTE_TABLE_SIZE,
>> -					       HUGEPTE_TABLE_SIZE,
>> -					       0,
>> -					       zero_ctor);
>> -	if (! huge_pgtable_cache)
>> -		panic("hugetlbpage_init(): could not create hugepte 
>> cache\n");
>> +	/* Add supported huge page sizes.  Need to change HUGE_MAX_HSTATE
>> +	 * and adjust PTE_NONCACHE_NUM if the number of supported huge page
>> +	 * sizes changes.
>> +	 */
>> +	set_huge_psize(MMU_PAGE_16M);
>> +	set_huge_psize(MMU_PAGE_64K);
>> +	set_huge_psize(MMU_PAGE_16G);
>> +
>> +	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
>> +		if (mmu_huge_psizes[psize]) {
>> +			huge_pgtable_cache(psize) = kmem_cache_create(
>> +						HUGEPTE_CACHE_NAME(psize),
>> +						HUGEPTE_TABLE_SIZE(psize),
>> +						HUGEPTE_TABLE_SIZE(psize),
>> +						0,
>> +						zero_ctor);
>> +			if (!huge_pgtable_cache(psize))
>> +				panic("hugetlbpage_init(): could not create 
>> %s"\
>> +				      "\n", HUGEPTE_CACHE_NAME(psize));
>> +		}
>> +	}
>>
>> 	return 0;
>> }
>> diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
>> index c0f5cff..55588d5 100644
>> --- a/arch/powerpc/mm/init_64.c
>> +++ b/arch/powerpc/mm/init_64.c
>> @@ -151,10 +151,10 @@ static const char 
>> *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
>> };
>>
>> #ifdef CONFIG_HUGETLB_PAGE
>> -/* Hugepages need one extra cache, initialized in hugetlbpage.c.  We
>> - * can't put into the tables above, because HPAGE_SHIFT is not compile
>> - * time constant. */
>> -struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+1];
>> +/* Hugepages need an extra cache per hugepagesize, initialized in
>> + * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
>> + * is not compile time constant. */
>> +struct kmem_cache 
>> *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
>> #else
>> struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
>> #endif
>> diff --git a/arch/powerpc/mm/tlb_64.c b/arch/powerpc/mm/tlb_64.c
>> index e2d867c..8d79e16 100644
>> --- a/arch/powerpc/mm/tlb_64.c
>> +++ b/arch/powerpc/mm/tlb_64.c
>> @@ -150,7 +150,7 @@ void hpte_need_flush(struct mm_struct *mm, unsigned 
>> long addr,
>> 	 */
>> 	if (huge) {
>> #ifdef CONFIG_HUGETLB_PAGE
>> -		psize = mmu_huge_psize;
>> +		psize = get_slice_psize(mm, addr);;
>> #else
>> 		BUG();
>> 		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */
>> diff --git a/include/asm-powerpc/mmu-hash64.h 
>> b/include/asm-powerpc/mmu-hash64.h
>> index db1276a..63b0fa5 100644
>> --- a/include/asm-powerpc/mmu-hash64.h
>> +++ b/include/asm-powerpc/mmu-hash64.h
>> @@ -192,9 +192,9 @@ extern int mmu_ci_restrictions;
>>
>> #ifdef CONFIG_HUGETLB_PAGE
>> /*
>> - * The page size index of the huge pages for use by hugetlbfs
>> + * The page size indexes of the huge pages for use by hugetlbfs
>>  */
>> -extern int mmu_huge_psize;
>> +extern unsigned int mmu_huge_psizes[MMU_PAGE_COUNT];
>>
>> #endif /* CONFIG_HUGETLB_PAGE */
>>
>> diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h
>> index 67834ea..bdf453b 100644
>> --- a/include/asm-powerpc/page_64.h
>> +++ b/include/asm-powerpc/page_64.h
>> @@ -90,6 +90,7 @@ extern unsigned int HPAGE_SHIFT;
>> #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
>> #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
>> #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
>> +#define HUGE_MAX_HSTATE		3
>>
>> #endif /* __ASSEMBLY__ */
>>
>> diff --git a/include/asm-powerpc/pgalloc-64.h 
>> b/include/asm-powerpc/pgalloc-64.h
>> index 6898099..812a1d8 100644
>> --- a/include/asm-powerpc/pgalloc-64.h
>> +++ b/include/asm-powerpc/pgalloc-64.h
>> @@ -22,7 +22,7 @@ extern struct kmem_cache *pgtable_cache[];
>> #define PUD_CACHE_NUM		1
>> #define PMD_CACHE_NUM		1
>> #define HUGEPTE_CACHE_NUM	2
>> -#define PTE_NONCACHE_NUM	3  /* from GFP rather than kmem_cache */
>> +#define PTE_NONCACHE_NUM	7  /* from GFP rather than kmem_cache */
>>
>> static inline pgd_t *pgd_alloc(struct mm_struct *mm)
>> {
>> @@ -119,7 +119,7 @@ static inline void pte_free(struct mm_struct *mm, 
>> pgtable_t ptepage)
>> 	__free_page(ptepage);
>> }
>>
>> -#define PGF_CACHENUM_MASK	0x3
>> +#define PGF_CACHENUM_MASK	0x7
>>
>> typedef struct pgtable_free {
>> 	unsigned long val;
>>
>>     

Re: [PATCH 0/6] 16G and multi size hugetlb page support on powerpc

[Nick Piggin]

On Tue, May 13, 2008 at 12:07:15PM -0500, Jon Tollefson wrote:
> This patch set builds on Nick Piggin's patches for multi size and giant 
> hugetlb page support of April 22.  The following set of patches adds 
> support for 16G huge pages on ppc64 and support for multiple huge page 
> sizes at the same time on ppc64.  Thus allowing 64K, 16M, and 16G huge 
> pages given a POWER5+ or later machine.
> 
> New to this version of my patch is numerous bug fixes and cleanups, but 
> the biggest change is the support for multiple huge page sizes on power.
> 
> patch 1: changes to generic hugetlb to enable 16G pages on power
> patch 2: powerpc: adds function for allocating 16G pages
> patch 3: powerpc: setups 16G page locations found in device tree
> patch 4: powerpc: page definition support for 16G pages
> patch 5: check for overflow when user space is 32bit
> patch 6: powerpc: multiple huge page size support

Hi Jon,

Thanks very much. I'll put these at the end of my patchset and attempt
to keep them building if I make changes to the core code (have to spend
a bit of time catching up with the review comments from last round).

I'll send out another patchset for review in a day or so after I catch
up, and then hopefully get it merged in -mm for 2.6.27.

Thanks,
Nick

Re: [PATCH 0/6] 16G and multi size hugetlb page support on powerpc

[Nick Piggin]

On Tue, May 13, 2008 at 12:07:15PM -0500, Jon Tollefson wrote:
> This patch set builds on Nick Piggin's patches for multi size and giant 
> hugetlb page support of April 22.  The following set of patches adds 
> support for 16G huge pages on ppc64 and support for multiple huge page 
> sizes at the same time on ppc64.  Thus allowing 64K, 16M, and 16G huge 
> pages given a POWER5+ or later machine.
> 
> New to this version of my patch is numerous bug fixes and cleanups, but 
> the biggest change is the support for multiple huge page sizes on power.
> 
> patch 1: changes to generic hugetlb to enable 16G pages on power
> patch 2: powerpc: adds function for allocating 16G pages
> patch 3: powerpc: setups 16G page locations found in device tree
> patch 4: powerpc: page definition support for 16G pages
> patch 5: check for overflow when user space is 32bit
> patch 6: powerpc: multiple huge page size support

Hi Jon,

Thanks very much. I'll put these at the end of my patchset and attempt
to keep them building if I make changes to the core code (have to spend
a bit of time catching up with the review comments from last round).

I'll send out another patchset for review in a day or so after I catch
up, and then hopefully get it merged in -mm for 2.6.27.

Thanks,
Nick

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Re: [PATCH 0/6] 16G and multi size hugetlb page support on powerpc

[Nick Piggin]

On Tue, May 13, 2008 at 12:07:15PM -0500, Jon Tollefson wrote:
> This patch set builds on Nick Piggin's patches for multi size and giant 
> hugetlb page support of April 22.  The following set of patches adds 
> support for 16G huge pages on ppc64 and support for multiple huge page 
> sizes at the same time on ppc64.  Thus allowing 64K, 16M, and 16G huge 
> pages given a POWER5+ or later machine.
> 
> New to this version of my patch is numerous bug fixes and cleanups, but 
> the biggest change is the support for multiple huge page sizes on power.
> 
> patch 1: changes to generic hugetlb to enable 16G pages on power
> patch 2: powerpc: adds function for allocating 16G pages
> patch 3: powerpc: setups 16G page locations found in device tree
> patch 4: powerpc: page definition support for 16G pages
> patch 5: check for overflow when user space is 32bit
> patch 6: powerpc: multiple huge page size support

Hi Jon,

Thanks very much. I'll put these at the end of my patchset and attempt
to keep them building if I make changes to the core code (have to spend
a bit of time catching up with the review comments from last round).

I'll send out another patchset for review in a day or so after I catch
up, and then hopefully get it merged in -mm for 2.6.27.

Thanks,
Nick