* [PATCH 1/5] arch/kmap: Remove BUG_ON()
2020-04-26 5:54 [PATCH 0/5] Remove duplicated kmap code ira.weiny
@ 2020-04-26 5:54 ` ira.weiny
2020-04-26 5:54 ` [PATCH 2/5] arch/kmap: Remove redundant arch specific kmaps ira.weiny
` (3 subsequent siblings)
4 siblings, 0 replies; 11+ messages in thread
From: ira.weiny @ 2020-04-26 5:54 UTC (permalink / raw)
To: linux-kernel, Andrew Morton
Cc: Peter Zijlstra, Dave Hansen, James E.J. Bottomley, Max Filippov,
Paul Mackerras, H. Peter Anvin, sparclinux, Ira Weiny,
Dan Williams, Helge Deller, x86, linux-csky, Ingo Molnar,
linux-snps-arc, linux-xtensa, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-mips, linuxppc-dev,
David S. Miller
From: Ira Weiny <ira.weiny@intel.com>
Replace the use of BUG_ON(in_interrupt()) in the kmap() and kunmap()
in favor of might_sleep().
Besides the benefits of might_sleep(), this normalizes the
implementations such that they can be made generic in subsequent
patches.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
arch/arc/include/asm/highmem.h | 2 +-
arch/arc/mm/highmem.c | 2 +-
arch/arm/mm/highmem.c | 2 +-
arch/csky/mm/highmem.c | 2 +-
arch/microblaze/include/asm/highmem.h | 2 +-
arch/mips/mm/highmem.c | 2 +-
arch/nds32/mm/highmem.c | 2 +-
arch/powerpc/include/asm/highmem.h | 2 +-
arch/sparc/include/asm/highmem.h | 4 ++--
arch/x86/mm/highmem_32.c | 3 +--
arch/xtensa/include/asm/highmem.h | 4 ++--
11 files changed, 13 insertions(+), 14 deletions(-)
diff --git a/arch/arc/include/asm/highmem.h b/arch/arc/include/asm/highmem.h
index 1af00accb37f..042e92921c4c 100644
--- a/arch/arc/include/asm/highmem.h
+++ b/arch/arc/include/asm/highmem.h
@@ -45,7 +45,7 @@ static inline void flush_cache_kmaps(void)
static inline void kunmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
index fc8849e4f72e..39ef7b9a3aa9 100644
--- a/arch/arc/mm/highmem.c
+++ b/arch/arc/mm/highmem.c
@@ -51,7 +51,7 @@ static pte_t * fixmap_page_table;
void *kmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return page_address(page);
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index a76f8ace9ce6..cc6eb79ef20c 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -42,7 +42,7 @@ EXPORT_SYMBOL(kmap);
void kunmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
index 813129145f3d..690d678649d1 100644
--- a/arch/csky/mm/highmem.c
+++ b/arch/csky/mm/highmem.c
@@ -29,7 +29,7 @@ EXPORT_SYMBOL(kmap);
void kunmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
diff --git a/arch/microblaze/include/asm/highmem.h b/arch/microblaze/include/asm/highmem.h
index 332c78e15198..99ced7278b5c 100644
--- a/arch/microblaze/include/asm/highmem.h
+++ b/arch/microblaze/include/asm/highmem.h
@@ -66,7 +66,7 @@ static inline void *kmap(struct page *page)
static inline void kunmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
index d08e6d7d533b..edd889f6cede 100644
--- a/arch/mips/mm/highmem.c
+++ b/arch/mips/mm/highmem.c
@@ -28,7 +28,7 @@ EXPORT_SYMBOL(kmap);
void kunmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
index 022779af6148..4c7c28e994ea 100644
--- a/arch/nds32/mm/highmem.c
+++ b/arch/nds32/mm/highmem.c
@@ -24,7 +24,7 @@ EXPORT_SYMBOL(kmap);
void kunmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h
index a4b65b186ec6..529512f6d65a 100644
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -74,7 +74,7 @@ static inline void *kmap(struct page *page)
static inline void kunmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
diff --git a/arch/sparc/include/asm/highmem.h b/arch/sparc/include/asm/highmem.h
index 18d776925c45..7dd2d4b3f980 100644
--- a/arch/sparc/include/asm/highmem.h
+++ b/arch/sparc/include/asm/highmem.h
@@ -55,7 +55,7 @@ void kunmap_high(struct page *page);
static inline void *kmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return page_address(page);
return kmap_high(page);
@@ -63,7 +63,7 @@ static inline void *kmap(struct page *page)
static inline void kunmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 0a1898b8552e..8af66382672b 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -15,8 +15,7 @@ EXPORT_SYMBOL(kmap);
void kunmap(struct page *page)
{
- if (in_interrupt())
- BUG();
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h
index 04e9340eac4b..413848cc1e56 100644
--- a/arch/xtensa/include/asm/highmem.h
+++ b/arch/xtensa/include/asm/highmem.h
@@ -73,7 +73,7 @@ static inline void *kmap(struct page *page)
*/
BUILD_BUG_ON(PKMAP_BASE <
TLBTEMP_BASE_1 + TLBTEMP_SIZE);
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return page_address(page);
return kmap_high(page);
@@ -81,7 +81,7 @@ static inline void *kmap(struct page *page)
static inline void kunmap(struct page *page)
{
- BUG_ON(in_interrupt());
+ might_sleep();
if (!PageHighMem(page))
return;
kunmap_high(page);
--
2.25.1
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH 2/5] arch/kmap: Remove redundant arch specific kmaps
2020-04-26 5:54 [PATCH 0/5] Remove duplicated kmap code ira.weiny
2020-04-26 5:54 ` [PATCH 1/5] arch/kmap: Remove BUG_ON() ira.weiny
@ 2020-04-26 5:54 ` ira.weiny
2020-04-26 7:17 ` Christoph Hellwig
2020-04-26 5:54 ` [PATCH 3/5] arch/kunmap: Remove duplicate kunmap implementations ira.weiny
` (2 subsequent siblings)
4 siblings, 1 reply; 11+ messages in thread
From: ira.weiny @ 2020-04-26 5:54 UTC (permalink / raw)
To: linux-kernel, Andrew Morton
Cc: Peter Zijlstra, Dave Hansen, James E.J. Bottomley, Max Filippov,
Paul Mackerras, H. Peter Anvin, sparclinux, Ira Weiny,
Dan Williams, Helge Deller, x86, linux-csky, Ingo Molnar,
linux-snps-arc, linux-xtensa, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-mips, linuxppc-dev,
David S. Miller
From: Ira Weiny <ira.weiny@intel.com>
The kmap code for all the architectures is almost 100% identical.
Lift the common code to the core. Use ARCH_HAS_KMAP to indicate if an
arch needs a special kmap.
This also has the benefit of changing kmap() on a number of
architectures to be an inline call rather than an actual function.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
arch/arc/include/asm/highmem.h | 2 --
arch/arc/mm/highmem.c | 10 ----------
arch/arm/include/asm/highmem.h | 2 --
arch/arm/mm/highmem.c | 9 ---------
arch/csky/include/asm/highmem.h | 2 +-
arch/csky/mm/highmem.c | 7 +------
arch/microblaze/include/asm/highmem.h | 9 ---------
arch/mips/include/asm/highmem.h | 2 +-
arch/mips/mm/highmem.c | 7 +------
arch/nds32/include/asm/highmem.h | 2 --
arch/nds32/mm/highmem.c | 12 ------------
arch/powerpc/include/asm/highmem.h | 9 ---------
arch/sparc/include/asm/highmem.h | 9 ---------
arch/x86/include/asm/highmem.h | 2 --
arch/x86/mm/highmem_32.c | 9 ---------
arch/xtensa/include/asm/highmem.h | 6 +-----
include/linux/highmem.h | 18 ++++++++++++++++++
17 files changed, 23 insertions(+), 94 deletions(-)
diff --git a/arch/arc/include/asm/highmem.h b/arch/arc/include/asm/highmem.h
index 042e92921c4c..96eb67c86961 100644
--- a/arch/arc/include/asm/highmem.h
+++ b/arch/arc/include/asm/highmem.h
@@ -30,8 +30,6 @@
#include <asm/cacheflush.h>
-extern void *kmap(struct page *page);
-extern void *kmap_high(struct page *page);
extern void *kmap_atomic(struct page *page);
extern void __kunmap_atomic(void *kvaddr);
extern void kunmap_high(struct page *page);
diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
index 39ef7b9a3aa9..4db13a6b9f3b 100644
--- a/arch/arc/mm/highmem.c
+++ b/arch/arc/mm/highmem.c
@@ -49,16 +49,6 @@
extern pte_t * pkmap_page_table;
static pte_t * fixmap_page_table;
-void *kmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
-
- return kmap_high(page);
-}
-EXPORT_SYMBOL(kmap);
-
void *kmap_atomic(struct page *page)
{
int idx, cpu_idx;
diff --git a/arch/arm/include/asm/highmem.h b/arch/arm/include/asm/highmem.h
index eb4e4207cd3c..c917522541de 100644
--- a/arch/arm/include/asm/highmem.h
+++ b/arch/arm/include/asm/highmem.h
@@ -20,7 +20,6 @@
extern pte_t *pkmap_page_table;
-extern void *kmap_high(struct page *page);
extern void kunmap_high(struct page *page);
/*
@@ -63,7 +62,6 @@ static inline void *kmap_high_get(struct page *page)
* when CONFIG_HIGHMEM is not set.
*/
#ifdef CONFIG_HIGHMEM
-extern void *kmap(struct page *page);
extern void kunmap(struct page *page);
extern void *kmap_atomic(struct page *page);
extern void __kunmap_atomic(void *kvaddr);
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index cc6eb79ef20c..e8ba37c36590 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -31,15 +31,6 @@ static inline pte_t get_fixmap_pte(unsigned long vaddr)
return *ptep;
}
-void *kmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- return kmap_high(page);
-}
-EXPORT_SYMBOL(kmap);
-
void kunmap(struct page *page)
{
might_sleep();
diff --git a/arch/csky/include/asm/highmem.h b/arch/csky/include/asm/highmem.h
index a345a2f2c22e..4caeff143748 100644
--- a/arch/csky/include/asm/highmem.h
+++ b/arch/csky/include/asm/highmem.h
@@ -30,9 +30,9 @@ extern pte_t *pkmap_page_table;
#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
-extern void *kmap_high(struct page *page);
extern void kunmap_high(struct page *page);
+#define ARCH_HAS_KMAP
extern void *kmap(struct page *page);
extern void kunmap(struct page *page);
extern void *kmap_atomic(struct page *page);
diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
index 690d678649d1..5fb0bd855444 100644
--- a/arch/csky/mm/highmem.c
+++ b/arch/csky/mm/highmem.c
@@ -15,14 +15,9 @@ unsigned long highstart_pfn, highend_pfn;
void *kmap(struct page *page)
{
- void *addr;
+ void *addr = kmap_generic(page);
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- addr = kmap_high(page);
flush_tlb_one((unsigned long)addr);
-
return addr;
}
EXPORT_SYMBOL(kmap);
diff --git a/arch/microblaze/include/asm/highmem.h b/arch/microblaze/include/asm/highmem.h
index 99ced7278b5c..8c5bfd228bd8 100644
--- a/arch/microblaze/include/asm/highmem.h
+++ b/arch/microblaze/include/asm/highmem.h
@@ -51,19 +51,10 @@ extern pte_t *pkmap_page_table;
#define PKMAP_NR(virt) ((virt - PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
-extern void *kmap_high(struct page *page);
extern void kunmap_high(struct page *page);
extern void *kmap_atomic_prot(struct page *page, pgprot_t prot);
extern void __kunmap_atomic(void *kvaddr);
-static inline void *kmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- return kmap_high(page);
-}
-
static inline void kunmap(struct page *page)
{
might_sleep();
diff --git a/arch/mips/include/asm/highmem.h b/arch/mips/include/asm/highmem.h
index 9d84aafc33d0..c30bbb88fcfe 100644
--- a/arch/mips/include/asm/highmem.h
+++ b/arch/mips/include/asm/highmem.h
@@ -46,9 +46,9 @@ extern pte_t *pkmap_page_table;
#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
-extern void * kmap_high(struct page *page);
extern void kunmap_high(struct page *page);
+#define ARCH_HAS_KMAP
extern void *kmap(struct page *page);
extern void kunmap(struct page *page);
extern void *kmap_atomic(struct page *page);
diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
index edd889f6cede..3867dbe9ef32 100644
--- a/arch/mips/mm/highmem.c
+++ b/arch/mips/mm/highmem.c
@@ -14,14 +14,9 @@ unsigned long highstart_pfn, highend_pfn;
void *kmap(struct page *page)
{
- void *addr;
+ void *addr = kmap_generic(page);
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- addr = kmap_high(page);
flush_tlb_one((unsigned long)addr);
-
return addr;
}
EXPORT_SYMBOL(kmap);
diff --git a/arch/nds32/include/asm/highmem.h b/arch/nds32/include/asm/highmem.h
index b3a82c97ded3..b13654a79069 100644
--- a/arch/nds32/include/asm/highmem.h
+++ b/arch/nds32/include/asm/highmem.h
@@ -44,7 +44,6 @@ extern unsigned long highstart_pfn, highend_pfn;
extern pte_t *pkmap_page_table;
-extern void *kmap_high(struct page *page);
extern void kunmap_high(struct page *page);
extern void kmap_init(void);
@@ -54,7 +53,6 @@ extern void kmap_init(void);
* when CONFIG_HIGHMEM is not set.
*/
#ifdef CONFIG_HIGHMEM
-extern void *kmap(struct page *page);
extern void kunmap(struct page *page);
extern void *kmap_atomic(struct page *page);
extern void __kunmap_atomic(void *kvaddr);
diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
index 4c7c28e994ea..d0cde53b84ae 100644
--- a/arch/nds32/mm/highmem.c
+++ b/arch/nds32/mm/highmem.c
@@ -10,18 +10,6 @@
#include <asm/fixmap.h>
#include <asm/tlbflush.h>
-void *kmap(struct page *page)
-{
- unsigned long vaddr;
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- vaddr = (unsigned long)kmap_high(page);
- return (void *)vaddr;
-}
-
-EXPORT_SYMBOL(kmap);
-
void kunmap(struct page *page)
{
might_sleep();
diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h
index 529512f6d65a..f14e4feef6d5 100644
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -59,19 +59,10 @@ extern pte_t *pkmap_page_table;
#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
-extern void *kmap_high(struct page *page);
extern void kunmap_high(struct page *page);
extern void *kmap_atomic_prot(struct page *page, pgprot_t prot);
extern void __kunmap_atomic(void *kvaddr);
-static inline void *kmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- return kmap_high(page);
-}
-
static inline void kunmap(struct page *page)
{
might_sleep();
diff --git a/arch/sparc/include/asm/highmem.h b/arch/sparc/include/asm/highmem.h
index 7dd2d4b3f980..2ff1192047f7 100644
--- a/arch/sparc/include/asm/highmem.h
+++ b/arch/sparc/include/asm/highmem.h
@@ -50,17 +50,8 @@ void kmap_init(void) __init;
#define PKMAP_END (PKMAP_ADDR(LAST_PKMAP))
-void *kmap_high(struct page *page);
void kunmap_high(struct page *page);
-static inline void *kmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- return kmap_high(page);
-}
-
static inline void kunmap(struct page *page)
{
might_sleep();
diff --git a/arch/x86/include/asm/highmem.h b/arch/x86/include/asm/highmem.h
index a8059930056d..c916a28a9738 100644
--- a/arch/x86/include/asm/highmem.h
+++ b/arch/x86/include/asm/highmem.h
@@ -58,10 +58,8 @@ extern unsigned long highstart_pfn, highend_pfn;
#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
-extern void *kmap_high(struct page *page);
extern void kunmap_high(struct page *page);
-void *kmap(struct page *page);
void kunmap(struct page *page);
void *kmap_atomic_prot(struct page *page, pgprot_t prot);
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 8af66382672b..12591a81b85c 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -4,15 +4,6 @@
#include <linux/swap.h> /* for totalram_pages */
#include <linux/memblock.h>
-void *kmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- return kmap_high(page);
-}
-EXPORT_SYMBOL(kmap);
-
void kunmap(struct page *page)
{
might_sleep();
diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h
index 413848cc1e56..fac4f48bde6c 100644
--- a/arch/xtensa/include/asm/highmem.h
+++ b/arch/xtensa/include/asm/highmem.h
@@ -63,7 +63,6 @@ static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
extern pte_t *pkmap_page_table;
-void *kmap_high(struct page *page);
void kunmap_high(struct page *page);
static inline void *kmap(struct page *page)
@@ -73,10 +72,7 @@ static inline void *kmap(struct page *page)
*/
BUILD_BUG_ON(PKMAP_BASE <
TLBTEMP_BASE_1 + TLBTEMP_SIZE);
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- return kmap_high(page);
+ return kmap_generic(page);
}
static inline void kunmap(struct page *page)
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index ea5cdbd8c2c3..2f7f710b7e7d 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -32,8 +32,26 @@ static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
#include <asm/kmap_types.h>
#ifdef CONFIG_HIGHMEM
+extern void *kmap_high(struct page *page);
+
+/* kmap_generic: architecture independent portion of kmap calls */
+static inline void *kmap_generic(struct page *page)
+{
+ might_sleep();
+ if (!PageHighMem(page))
+ return page_address(page);
+ return kmap_high(page);
+}
+
#include <asm/highmem.h>
+#ifndef ARCH_HAS_KMAP
+static inline void *kmap(struct page *page)
+{
+ return kmap_generic(page);
+}
+#endif
+
/* declarations for linux/mm/highmem.c */
unsigned int nr_free_highpages(void);
extern atomic_long_t _totalhigh_pages;
--
2.25.1
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: [PATCH 2/5] arch/kmap: Remove redundant arch specific kmaps
2020-04-26 5:54 ` [PATCH 2/5] arch/kmap: Remove redundant arch specific kmaps ira.weiny
@ 2020-04-26 7:17 ` Christoph Hellwig
2020-04-26 22:23 ` Ira Weiny
0 siblings, 1 reply; 11+ messages in thread
From: Christoph Hellwig @ 2020-04-26 7:17 UTC (permalink / raw)
To: ira.weiny
Cc: Peter Zijlstra, Dave Hansen, linux-mips, James E.J. Bottomley,
Max Filippov, Paul Mackerras, H. Peter Anvin, sparclinux,
Dan Williams, Helge Deller, x86, linux-csky, Ingo Molnar,
linux-snps-arc, linux-xtensa, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-kernel, Andrew Morton,
linuxppc-dev, David S. Miller
On Sat, Apr 25, 2020 at 10:54:03PM -0700, ira.weiny@intel.com wrote:
> From: Ira Weiny <ira.weiny@intel.com>
>
> The kmap code for all the architectures is almost 100% identical.
>
> Lift the common code to the core. Use ARCH_HAS_KMAP to indicate if an
> arch needs a special kmap.
Can you add a kmap_flush_tlb hook that csky and mips define, and the
just entirely consolidate the code instead?
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 2/5] arch/kmap: Remove redundant arch specific kmaps
2020-04-26 7:17 ` Christoph Hellwig
@ 2020-04-26 22:23 ` Ira Weiny
0 siblings, 0 replies; 11+ messages in thread
From: Ira Weiny @ 2020-04-26 22:23 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Peter Zijlstra, Dave Hansen, linux-mips, James E.J. Bottomley,
Max Filippov, Paul Mackerras, H. Peter Anvin, sparclinux,
Dan Williams, Helge Deller, x86, linux-csky, Ingo Molnar,
linux-snps-arc, linux-xtensa, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-kernel, Andrew Morton,
linuxppc-dev, David S. Miller
On Sun, Apr 26, 2020 at 12:17:15AM -0700, Christoph Hellwig wrote:
> On Sat, Apr 25, 2020 at 10:54:03PM -0700, ira.weiny@intel.com wrote:
> > From: Ira Weiny <ira.weiny@intel.com>
> >
> > The kmap code for all the architectures is almost 100% identical.
> >
> > Lift the common code to the core. Use ARCH_HAS_KMAP to indicate if an
> > arch needs a special kmap.
>
> Can you add a kmap_flush_tlb hook that csky and mips define, and the
> just entirely consolidate the code instead?
Sure that seems to work.
Ira
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 3/5] arch/kunmap: Remove duplicate kunmap implementations
2020-04-26 5:54 [PATCH 0/5] Remove duplicated kmap code ira.weiny
2020-04-26 5:54 ` [PATCH 1/5] arch/kmap: Remove BUG_ON() ira.weiny
2020-04-26 5:54 ` [PATCH 2/5] arch/kmap: Remove redundant arch specific kmaps ira.weiny
@ 2020-04-26 5:54 ` ira.weiny
2020-04-26 5:54 ` [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code ira.weiny
2020-04-26 5:54 ` [PATCH 5/5] arch/kunmap_atomic: " ira.weiny
4 siblings, 0 replies; 11+ messages in thread
From: ira.weiny @ 2020-04-26 5:54 UTC (permalink / raw)
To: linux-kernel, Andrew Morton
Cc: Peter Zijlstra, Dave Hansen, James E.J. Bottomley, Max Filippov,
Paul Mackerras, H. Peter Anvin, sparclinux, Ira Weiny,
Dan Williams, Helge Deller, x86, linux-csky, Ingo Molnar,
linux-snps-arc, linux-xtensa, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-mips, linuxppc-dev,
David S. Miller
From: Ira Weiny <ira.weiny@intel.com>
All architectures do exactly the same thing for kunmap(); remove all the
duplicate definitions and lift the call to the core.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
arch/arc/include/asm/highmem.h | 9 ---------
arch/arm/include/asm/highmem.h | 1 -
arch/arm/mm/highmem.c | 9 ---------
arch/csky/include/asm/highmem.h | 1 -
arch/csky/mm/highmem.c | 9 ---------
arch/microblaze/include/asm/highmem.h | 8 --------
arch/mips/include/asm/highmem.h | 1 -
arch/mips/mm/highmem.c | 9 ---------
arch/nds32/include/asm/highmem.h | 1 -
arch/nds32/mm/highmem.c | 10 ----------
arch/powerpc/include/asm/highmem.h | 8 --------
arch/sparc/include/asm/highmem.h | 8 --------
arch/x86/include/asm/highmem.h | 2 --
arch/x86/mm/highmem_32.c | 9 ---------
arch/xtensa/include/asm/highmem.h | 8 --------
include/linux/highmem.h | 8 ++++++++
16 files changed, 8 insertions(+), 93 deletions(-)
diff --git a/arch/arc/include/asm/highmem.h b/arch/arc/include/asm/highmem.h
index 96eb67c86961..c03a911c9f21 100644
--- a/arch/arc/include/asm/highmem.h
+++ b/arch/arc/include/asm/highmem.h
@@ -41,15 +41,6 @@ static inline void flush_cache_kmaps(void)
flush_cache_all();
}
-static inline void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-
-
#endif
#endif
diff --git a/arch/arm/include/asm/highmem.h b/arch/arm/include/asm/highmem.h
index c917522541de..829e3b969819 100644
--- a/arch/arm/include/asm/highmem.h
+++ b/arch/arm/include/asm/highmem.h
@@ -62,7 +62,6 @@ static inline void *kmap_high_get(struct page *page)
* when CONFIG_HIGHMEM is not set.
*/
#ifdef CONFIG_HIGHMEM
-extern void kunmap(struct page *page);
extern void *kmap_atomic(struct page *page);
extern void __kunmap_atomic(void *kvaddr);
extern void *kmap_atomic_pfn(unsigned long pfn);
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index e8ba37c36590..c700b32350ee 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -31,15 +31,6 @@ static inline pte_t get_fixmap_pte(unsigned long vaddr)
return *ptep;
}
-void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-EXPORT_SYMBOL(kunmap);
-
void *kmap_atomic(struct page *page)
{
unsigned int idx;
diff --git a/arch/csky/include/asm/highmem.h b/arch/csky/include/asm/highmem.h
index 4caeff143748..a0e7c43731a0 100644
--- a/arch/csky/include/asm/highmem.h
+++ b/arch/csky/include/asm/highmem.h
@@ -34,7 +34,6 @@ extern void kunmap_high(struct page *page);
#define ARCH_HAS_KMAP
extern void *kmap(struct page *page);
-extern void kunmap(struct page *page);
extern void *kmap_atomic(struct page *page);
extern void __kunmap_atomic(void *kvaddr);
extern void *kmap_atomic_pfn(unsigned long pfn);
diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
index 5fb0bd855444..69b1931986ae 100644
--- a/arch/csky/mm/highmem.c
+++ b/arch/csky/mm/highmem.c
@@ -22,15 +22,6 @@ void *kmap(struct page *page)
}
EXPORT_SYMBOL(kmap);
-void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-EXPORT_SYMBOL(kunmap);
-
void *kmap_atomic(struct page *page)
{
unsigned long vaddr;
diff --git a/arch/microblaze/include/asm/highmem.h b/arch/microblaze/include/asm/highmem.h
index 8c5bfd228bd8..1cbd52a0e39b 100644
--- a/arch/microblaze/include/asm/highmem.h
+++ b/arch/microblaze/include/asm/highmem.h
@@ -55,14 +55,6 @@ extern void kunmap_high(struct page *page);
extern void *kmap_atomic_prot(struct page *page, pgprot_t prot);
extern void __kunmap_atomic(void *kvaddr);
-static inline void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-
static inline void *kmap_atomic(struct page *page)
{
return kmap_atomic_prot(page, kmap_prot);
diff --git a/arch/mips/include/asm/highmem.h b/arch/mips/include/asm/highmem.h
index c30bbb88fcfe..af9a66300628 100644
--- a/arch/mips/include/asm/highmem.h
+++ b/arch/mips/include/asm/highmem.h
@@ -50,7 +50,6 @@ extern void kunmap_high(struct page *page);
#define ARCH_HAS_KMAP
extern void *kmap(struct page *page);
-extern void kunmap(struct page *page);
extern void *kmap_atomic(struct page *page);
extern void __kunmap_atomic(void *kvaddr);
extern void *kmap_atomic_pfn(unsigned long pfn);
diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
index 3867dbe9ef32..c3c9fe962f0f 100644
--- a/arch/mips/mm/highmem.c
+++ b/arch/mips/mm/highmem.c
@@ -21,15 +21,6 @@ void *kmap(struct page *page)
}
EXPORT_SYMBOL(kmap);
-void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-EXPORT_SYMBOL(kunmap);
-
/*
* kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
* no global lock is needed and because the kmap code must perform a global TLB
diff --git a/arch/nds32/include/asm/highmem.h b/arch/nds32/include/asm/highmem.h
index b13654a79069..e455e2624247 100644
--- a/arch/nds32/include/asm/highmem.h
+++ b/arch/nds32/include/asm/highmem.h
@@ -53,7 +53,6 @@ extern void kmap_init(void);
* when CONFIG_HIGHMEM is not set.
*/
#ifdef CONFIG_HIGHMEM
-extern void kunmap(struct page *page);
extern void *kmap_atomic(struct page *page);
extern void __kunmap_atomic(void *kvaddr);
extern void *kmap_atomic_pfn(unsigned long pfn);
diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
index d0cde53b84ae..f9348bec0ecb 100644
--- a/arch/nds32/mm/highmem.c
+++ b/arch/nds32/mm/highmem.c
@@ -10,16 +10,6 @@
#include <asm/fixmap.h>
#include <asm/tlbflush.h>
-void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-
-EXPORT_SYMBOL(kunmap);
-
void *kmap_atomic(struct page *page)
{
unsigned int idx;
diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h
index f14e4feef6d5..08e02a4f3a8f 100644
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -63,14 +63,6 @@ extern void kunmap_high(struct page *page);
extern void *kmap_atomic_prot(struct page *page, pgprot_t prot);
extern void __kunmap_atomic(void *kvaddr);
-static inline void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-
static inline void *kmap_atomic(struct page *page)
{
return kmap_atomic_prot(page, kmap_prot);
diff --git a/arch/sparc/include/asm/highmem.h b/arch/sparc/include/asm/highmem.h
index 2ff1192047f7..b3ee234b2a8f 100644
--- a/arch/sparc/include/asm/highmem.h
+++ b/arch/sparc/include/asm/highmem.h
@@ -52,14 +52,6 @@ void kmap_init(void) __init;
void kunmap_high(struct page *page);
-static inline void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-
void *kmap_atomic(struct page *page);
void __kunmap_atomic(void *kvaddr);
diff --git a/arch/x86/include/asm/highmem.h b/arch/x86/include/asm/highmem.h
index c916a28a9738..102cdcde74cb 100644
--- a/arch/x86/include/asm/highmem.h
+++ b/arch/x86/include/asm/highmem.h
@@ -60,8 +60,6 @@ extern unsigned long highstart_pfn, highend_pfn;
extern void kunmap_high(struct page *page);
-void kunmap(struct page *page);
-
void *kmap_atomic_prot(struct page *page, pgprot_t prot);
void *kmap_atomic(struct page *page);
void __kunmap_atomic(void *kvaddr);
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 12591a81b85c..c4ebfd0ae401 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -4,15 +4,6 @@
#include <linux/swap.h> /* for totalram_pages */
#include <linux/memblock.h>
-void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-EXPORT_SYMBOL(kunmap);
-
/*
* kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
* no global lock is needed and because the kmap code must perform a global TLB
diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h
index fac4f48bde6c..ae9e0ffbdb80 100644
--- a/arch/xtensa/include/asm/highmem.h
+++ b/arch/xtensa/include/asm/highmem.h
@@ -75,14 +75,6 @@ static inline void *kmap(struct page *page)
return kmap_generic(page);
}
-static inline void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-
static inline void flush_cache_kmaps(void)
{
flush_cache_all();
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 2f7f710b7e7d..1a3b7690c78c 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -52,6 +52,14 @@ static inline void *kmap(struct page *page)
}
#endif
+static inline void kunmap(struct page *page)
+{
+ might_sleep();
+ if (!PageHighMem(page))
+ return;
+ kunmap_high(page);
+}
+
/* declarations for linux/mm/highmem.c */
unsigned int nr_free_highpages(void);
extern atomic_long_t _totalhigh_pages;
--
2.25.1
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code
2020-04-26 5:54 [PATCH 0/5] Remove duplicated kmap code ira.weiny
` (2 preceding siblings ...)
2020-04-26 5:54 ` [PATCH 3/5] arch/kunmap: Remove duplicate kunmap implementations ira.weiny
@ 2020-04-26 5:54 ` ira.weiny
2020-04-26 7:26 ` Christoph Hellwig
2020-04-26 5:54 ` [PATCH 5/5] arch/kunmap_atomic: " ira.weiny
4 siblings, 1 reply; 11+ messages in thread
From: ira.weiny @ 2020-04-26 5:54 UTC (permalink / raw)
To: linux-kernel, Andrew Morton
Cc: Peter Zijlstra, Dave Hansen, James E.J. Bottomley, Max Filippov,
Paul Mackerras, H. Peter Anvin, sparclinux, Ira Weiny,
Dan Williams, Helge Deller, x86, linux-csky, Ingo Molnar,
linux-snps-arc, linux-xtensa, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-mips, linuxppc-dev,
David S. Miller
From: Ira Weiny <ira.weiny@intel.com>
Every arch has the same check for a not HIGHMEM page. Define
kmap_atomic_fast() to quickly return already mapped pages and reduce the
code duplication by lifting this check to the core.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
arch/arc/mm/highmem.c | 7 +++----
arch/arm/mm/highmem.c | 8 +++-----
arch/csky/mm/highmem.c | 7 +++----
arch/microblaze/mm/highmem.c | 8 +++-----
arch/mips/mm/highmem.c | 7 +++----
arch/nds32/mm/highmem.c | 7 +++----
arch/powerpc/mm/highmem.c | 7 +++----
arch/sparc/mm/highmem.c | 7 +++----
arch/x86/mm/highmem_32.c | 8 +++-----
arch/xtensa/mm/highmem.c | 7 +++----
include/linux/highmem.h | 9 +++++++++
11 files changed, 39 insertions(+), 43 deletions(-)
diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
index 4db13a6b9f3b..1cae4b911a33 100644
--- a/arch/arc/mm/highmem.c
+++ b/arch/arc/mm/highmem.c
@@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page)
{
int idx, cpu_idx;
unsigned long vaddr;
+ void *addr = kmap_atomic_fast(page);
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
+ if (addr)
+ return addr;
cpu_idx = kmap_atomic_idx_push();
idx = cpu_idx + KM_TYPE_NR * smp_processor_id();
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index c700b32350ee..4a629f616a6a 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -35,13 +35,11 @@ void *kmap_atomic(struct page *page)
{
unsigned int idx;
unsigned long vaddr;
- void *kmap;
+ void *kmap = kmap_atomic_fast(page);
int type;
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
+ if (kmap)
+ return kmap;
#ifdef CONFIG_DEBUG_HIGHMEM
/*
diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
index 69b1931986ae..1191f57f53ae 100644
--- a/arch/csky/mm/highmem.c
+++ b/arch/csky/mm/highmem.c
@@ -25,12 +25,11 @@ EXPORT_SYMBOL(kmap);
void *kmap_atomic(struct page *page)
{
unsigned long vaddr;
+ void *addr = kmap_atomic_fast(page);
int idx, type;
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
+ if (addr)
+ return addr;
type = kmap_atomic_idx_push();
idx = type + KM_TYPE_NR*smp_processor_id();
diff --git a/arch/microblaze/mm/highmem.c b/arch/microblaze/mm/highmem.c
index d7569f77fa15..99fdf826edc2 100644
--- a/arch/microblaze/mm/highmem.c
+++ b/arch/microblaze/mm/highmem.c
@@ -36,13 +36,11 @@ void *kmap_atomic_prot(struct page *page, pgprot_t prot)
{
unsigned long vaddr;
+ void *addr = kmap_atomic_fast(page);
int idx, type;
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
-
+ if (addr)
+ return addr;
type = kmap_atomic_idx_push();
idx = type + KM_TYPE_NR*smp_processor_id();
diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
index c3c9fe962f0f..ba03ca75d4a1 100644
--- a/arch/mips/mm/highmem.c
+++ b/arch/mips/mm/highmem.c
@@ -33,12 +33,11 @@ EXPORT_SYMBOL(kmap);
void *kmap_atomic(struct page *page)
{
unsigned long vaddr;
+ void *addr = kmap_atomic_fast(page);
int idx, type;
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
+ if (addr)
+ return addr;
type = kmap_atomic_idx_push();
idx = type + KM_TYPE_NR*smp_processor_id();
diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
index f9348bec0ecb..4aabde586489 100644
--- a/arch/nds32/mm/highmem.c
+++ b/arch/nds32/mm/highmem.c
@@ -14,13 +14,12 @@ void *kmap_atomic(struct page *page)
{
unsigned int idx;
unsigned long vaddr, pte;
+ void *addr = kmap_atomic_fast(page);
int type;
pte_t *ptep;
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
+ if (addr)
+ return addr;
type = kmap_atomic_idx_push();
diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
index 320c1672b2ae..cdf5b716801a 100644
--- a/arch/powerpc/mm/highmem.c
+++ b/arch/powerpc/mm/highmem.c
@@ -33,12 +33,11 @@
void *kmap_atomic_prot(struct page *page, pgprot_t prot)
{
unsigned long vaddr;
+ void *addr = kmap_atomic_fast(page);
int idx, type;
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
+ if (addr)
+ return addr;
type = kmap_atomic_idx_push();
idx = type + KM_TYPE_NR*smp_processor_id();
diff --git a/arch/sparc/mm/highmem.c b/arch/sparc/mm/highmem.c
index d4a80adea7e5..178641805567 100644
--- a/arch/sparc/mm/highmem.c
+++ b/arch/sparc/mm/highmem.c
@@ -56,12 +56,11 @@ void __init kmap_init(void)
void *kmap_atomic(struct page *page)
{
unsigned long vaddr;
+ void *addr = kmap_atomic_fast(page);
long idx, type;
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
+ if (addr)
+ return addr;
type = kmap_atomic_idx_push();
idx = type + KM_TYPE_NR*smp_processor_id();
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index c4ebfd0ae401..34770499b0ff 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -15,13 +15,11 @@
void *kmap_atomic_prot(struct page *page, pgprot_t prot)
{
unsigned long vaddr;
+ void *addr = kmap_atomic_fast(page);
int idx, type;
- preempt_disable();
- pagefault_disable();
-
- if (!PageHighMem(page))
- return page_address(page);
+ if (addr)
+ return addr;
type = kmap_atomic_idx_push();
idx = type + KM_TYPE_NR*smp_processor_id();
diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c
index 184ceadccc1a..38c14e0b578c 100644
--- a/arch/xtensa/mm/highmem.c
+++ b/arch/xtensa/mm/highmem.c
@@ -41,11 +41,10 @@ void *kmap_atomic(struct page *page)
{
enum fixed_addresses idx;
unsigned long vaddr;
+ void *addr = kmap_atomic_fast(page);
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
+ if (addr)
+ return addr;
idx = kmap_idx(kmap_atomic_idx_push(),
DCACHE_ALIAS(page_to_phys(page)));
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 1a3b7690c78c..eee53e151900 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -60,6 +60,15 @@ static inline void kunmap(struct page *page)
kunmap_high(page);
}
+static inline void *kmap_atomic_fast(struct page *page)
+{
+ preempt_disable();
+ pagefault_disable();
+ if (!PageHighMem(page))
+ return page_address(page);
+ return NULL;
+}
+
/* declarations for linux/mm/highmem.c */
unsigned int nr_free_highpages(void);
extern atomic_long_t _totalhigh_pages;
--
2.25.1
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code
2020-04-26 5:54 ` [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code ira.weiny
@ 2020-04-26 7:26 ` Christoph Hellwig
2020-04-27 1:16 ` Ira Weiny
0 siblings, 1 reply; 11+ messages in thread
From: Christoph Hellwig @ 2020-04-26 7:26 UTC (permalink / raw)
To: ira.weiny
Cc: Peter Zijlstra, Dave Hansen, linux-mips, James E.J. Bottomley,
Max Filippov, Paul Mackerras, H. Peter Anvin, sparclinux,
Dan Williams, Helge Deller, x86, linux-csky, Ingo Molnar,
linux-snps-arc, linux-xtensa, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-kernel, Andrew Morton,
linuxppc-dev, David S. Miller
> diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
> index 4db13a6b9f3b..1cae4b911a33 100644
> --- a/arch/arc/mm/highmem.c
> +++ b/arch/arc/mm/highmem.c
> @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page)
> {
> int idx, cpu_idx;
> unsigned long vaddr;
> + void *addr = kmap_atomic_fast(page);
>
> - preempt_disable();
> - pagefault_disable();
> - if (!PageHighMem(page))
> - return page_address(page);
> + if (addr)
> + return addr;
Wouldn't it make sense to just move kmap_atomic itelf to common code,
and call out to a kmap_atomic_high for the highmem case, following the
scheme in kmap? Same for the unmap side. That might require to support
kmap_atomic_prot everywhere first, which sounds like a really good
idea anyway, and would avoid the need for strange workaround in drm.
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code
2020-04-26 7:26 ` Christoph Hellwig
@ 2020-04-27 1:16 ` Ira Weiny
2020-04-27 6:25 ` Christoph Hellwig
0 siblings, 1 reply; 11+ messages in thread
From: Ira Weiny @ 2020-04-27 1:16 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Peter Zijlstra, Dave Hansen, linux-mips, James E.J. Bottomley,
Max Filippov, Paul Mackerras, H. Peter Anvin, sparclinux,
Dan Williams, Helge Deller, x86, linux-csky, Ingo Molnar,
linux-snps-arc, linux-xtensa, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-kernel, Andrew Morton,
linuxppc-dev, David S. Miller
On Sun, Apr 26, 2020 at 12:26:42AM -0700, Christoph Hellwig wrote:
> > diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
> > index 4db13a6b9f3b..1cae4b911a33 100644
> > --- a/arch/arc/mm/highmem.c
> > +++ b/arch/arc/mm/highmem.c
> > @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page)
> > {
> > int idx, cpu_idx;
> > unsigned long vaddr;
> > + void *addr = kmap_atomic_fast(page);
> >
> > - preempt_disable();
> > - pagefault_disable();
> > - if (!PageHighMem(page))
> > - return page_address(page);
> > + if (addr)
> > + return addr;
>
> Wouldn't it make sense to just move kmap_atomic itelf to common code,
> and call out to a kmap_atomic_high for the highmem case, following the
> scheme in kmap?
>
Sure I do like that symmetry between the calls.
>
> Same for the unmap side.
FWIW that would simply be renaming __kunmap_atomic() to kunmap_atomic_high()
>
> That might require to support
> kmap_atomic_prot everywhere first, which sounds like a really good
> idea anyway, and would avoid the need for strange workaround in drm.
Having a kmap_atomic_prot() seems like a good idea. But I'm not exactly sure
why CONFIG_x86 is being called out specifically in the DRM code?
Ira
^ permalink raw reply [flat|nested] 11+ messages in thread* Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code
2020-04-27 1:16 ` Ira Weiny
@ 2020-04-27 6:25 ` Christoph Hellwig
0 siblings, 0 replies; 11+ messages in thread
From: Christoph Hellwig @ 2020-04-27 6:25 UTC (permalink / raw)
To: Ira Weiny
Cc: Peter Zijlstra, Dave Hansen, linux-mips, James E.J. Bottomley,
Max Filippov, Paul Mackerras, H. Peter Anvin, sparclinux,
Dan Williams, Helge Deller, x86, linux-csky, Christoph Hellwig,
Ingo Molnar, linux-snps-arc, linux-xtensa, Borislav Petkov,
Andy Lutomirski, Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-kernel, Andrew Morton,
linuxppc-dev, David S. Miller
On Sun, Apr 26, 2020 at 06:16:30PM -0700, Ira Weiny wrote:
> > That might require to support
> > kmap_atomic_prot everywhere first, which sounds like a really good
> > idea anyway, and would avoid the need for strange workaround in drm.
>
> Having a kmap_atomic_prot() seems like a good idea. But I'm not exactly sure
> why CONFIG_x86 is being called out specifically in the DRM code?
Probably because it only existed on x86 back then. And drm has a
tendency of working around core problems with hacks instead of doing
the fairly easy fixups.
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 5/5] arch/kunmap_atomic: Consolidate duplicate code
2020-04-26 5:54 [PATCH 0/5] Remove duplicated kmap code ira.weiny
` (3 preceding siblings ...)
2020-04-26 5:54 ` [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code ira.weiny
@ 2020-04-26 5:54 ` ira.weiny
4 siblings, 0 replies; 11+ messages in thread
From: ira.weiny @ 2020-04-26 5:54 UTC (permalink / raw)
To: linux-kernel, Andrew Morton
Cc: Peter Zijlstra, Dave Hansen, James E.J. Bottomley, Max Filippov,
Paul Mackerras, H. Peter Anvin, sparclinux, Ira Weiny,
Dan Williams, Helge Deller, x86, linux-csky, Ingo Molnar,
linux-snps-arc, linux-xtensa, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, linux-arm-kernel, Chris Zankel,
Thomas Bogendoerfer, linux-parisc, linux-mips, linuxppc-dev,
David S. Miller
From: Ira Weiny <ira.weiny@intel.com>
Every single architecture (including !CONFIG_HIGHMEM) calls...
pagefault_enable();
preempt_enable();
... before returning from __kunmap_atomic(). Lift this code into the
kunmap_atomic() macro.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
arch/arc/mm/highmem.c | 3 ---
arch/arm/mm/highmem.c | 2 --
arch/csky/mm/highmem.c | 5 +----
arch/microblaze/mm/highmem.c | 2 --
arch/mips/mm/highmem.c | 2 --
arch/nds32/mm/highmem.c | 2 --
arch/parisc/include/asm/cacheflush.h | 2 --
arch/powerpc/mm/highmem.c | 2 --
arch/sparc/mm/highmem.c | 2 --
arch/x86/mm/highmem_32.c | 3 ---
arch/xtensa/mm/highmem.c | 3 ---
include/linux/highmem.h | 6 ++++--
12 files changed, 5 insertions(+), 29 deletions(-)
diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
index 1cae4b911a33..0725fc56b016 100644
--- a/arch/arc/mm/highmem.c
+++ b/arch/arc/mm/highmem.c
@@ -91,9 +91,6 @@ void __kunmap_atomic(void *kv)
kmap_atomic_idx_pop();
}
-
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index 4a629f616a6a..4983bf18ec32 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -98,8 +98,6 @@ void __kunmap_atomic(void *kvaddr)
/* this address was obtained through kmap_high_get() */
kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
}
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
index 1191f57f53ae..106fa6773084 100644
--- a/arch/csky/mm/highmem.c
+++ b/arch/csky/mm/highmem.c
@@ -50,7 +50,7 @@ void __kunmap_atomic(void *kvaddr)
int idx;
if (vaddr < FIXADDR_START)
- goto out;
+ return;
#ifdef CONFIG_DEBUG_HIGHMEM
idx = KM_TYPE_NR*smp_processor_id() + kmap_atomic_idx();
@@ -63,9 +63,6 @@ void __kunmap_atomic(void *kvaddr)
(void) idx; /* to kill a warning */
#endif
kmap_atomic_idx_pop();
-out:
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/microblaze/mm/highmem.c b/arch/microblaze/mm/highmem.c
index 99fdf826edc2..d382c6821747 100644
--- a/arch/microblaze/mm/highmem.c
+++ b/arch/microblaze/mm/highmem.c
@@ -81,7 +81,5 @@ void __kunmap_atomic(void *kvaddr)
local_flush_tlb_page(NULL, vaddr);
kmap_atomic_idx_pop();
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
index ba03ca75d4a1..5a3fc7e84e66 100644
--- a/arch/mips/mm/highmem.c
+++ b/arch/mips/mm/highmem.c
@@ -79,8 +79,6 @@ void __kunmap_atomic(void *kvaddr)
}
#endif
kmap_atomic_idx_pop();
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
index 4aabde586489..b8862aafa189 100644
--- a/arch/nds32/mm/highmem.c
+++ b/arch/nds32/mm/highmem.c
@@ -49,8 +49,6 @@ void __kunmap_atomic(void *kvaddr)
ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
set_pte(ptep, 0);
}
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/parisc/include/asm/cacheflush.h b/arch/parisc/include/asm/cacheflush.h
index 0c83644bfa5c..c8458491b9af 100644
--- a/arch/parisc/include/asm/cacheflush.h
+++ b/arch/parisc/include/asm/cacheflush.h
@@ -125,8 +125,6 @@ static inline void *kmap_atomic(struct page *page)
static inline void __kunmap_atomic(void *addr)
{
flush_kernel_dcache_page_addr(addr);
- pagefault_enable();
- preempt_enable();
}
#define kmap_atomic_prot(page, prot) kmap_atomic(page)
diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
index cdf5b716801a..7dfccf519621 100644
--- a/arch/powerpc/mm/highmem.c
+++ b/arch/powerpc/mm/highmem.c
@@ -76,7 +76,5 @@ void __kunmap_atomic(void *kvaddr)
}
kmap_atomic_idx_pop();
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/sparc/mm/highmem.c b/arch/sparc/mm/highmem.c
index 178641805567..7a99a1097f67 100644
--- a/arch/sparc/mm/highmem.c
+++ b/arch/sparc/mm/highmem.c
@@ -130,7 +130,5 @@ void __kunmap_atomic(void *kvaddr)
#endif
kmap_atomic_idx_pop();
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 34770499b0ff..b20e81b2b833 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -78,9 +78,6 @@ void __kunmap_atomic(void *kvaddr)
BUG_ON(vaddr >= (unsigned long)high_memory);
}
#endif
-
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c
index 38c14e0b578c..9a49263e4cd6 100644
--- a/arch/xtensa/mm/highmem.c
+++ b/arch/xtensa/mm/highmem.c
@@ -77,9 +77,6 @@ void __kunmap_atomic(void *kvaddr)
kmap_atomic_idx_pop();
}
-
- pagefault_enable();
- preempt_enable();
}
EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index eee53e151900..94145d4200ab 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -133,8 +133,8 @@ static inline void *kmap_atomic(struct page *page)
static inline void __kunmap_atomic(void *addr)
{
- pagefault_enable();
- preempt_enable();
+ /* Nothing to do in the CONFIG_HIGHMEM=n case as kunmap_atomic()
+ * handles re-enabling faults + preemption */
}
#define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))
@@ -185,6 +185,8 @@ static inline void kmap_atomic_idx_pop(void)
do { \
BUILD_BUG_ON(__same_type((addr), struct page *)); \
__kunmap_atomic(addr); \
+ pagefault_enable(); \
+ preempt_enable(); \
} while (0)
--
2.25.1
^ permalink raw reply related [flat|nested] 11+ messages in thread