[PATCH 1/3] mm: split out a new pagewalk.h header from mm.h

Christoph Hellwig
2019-08-28T14:20:15Z

Add a new header for the two handful of users of the walk_page_range /
walk_page_vma interface instead of polluting all users of mm.h with it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Steven Price <steven.price@arm.com>
---
arch/openrisc/kernel/dma.c | 1 +
arch/powerpc/mm/book3s64/subpage_prot.c | 2 +-
arch/s390/mm/gmap.c | 2 +-
fs/proc/task_mmu.c | 2 +-
include/linux/mm.h | 46 ---------------------
include/linux/pagewalk.h | 54 +++++++++++++++++++++++++
mm/hmm.c | 2 +-
mm/madvise.c | 1 +
mm/memcontrol.c | 2 +-
mm/mempolicy.c | 2 +-
mm/migrate.c | 1 +
mm/mincore.c | 2 +-
mm/mprotect.c | 2 +-
mm/pagewalk.c | 2 +-
14 files changed, 66 insertions(+), 55 deletions(-)
create mode 100644 include/linux/pagewalk.h

diff --git a/arch/openrisc/kernel/dma.c b/arch/openrisc/kernel/dma.c
index b41a79fcdbd9..c7812e6effa2 100644
--- a/arch/openrisc/kernel/dma.c
+++ b/arch/openrisc/kernel/dma.c
@@ -16,6 +16,7 @@
*/

#include <linux/dma-noncoherent.h>
+#include <linux/pagewalk.h>

#include <asm/cpuinfo.h>
#include <asm/spr_defs.h>
diff --git a/arch/powerpc/mm/book3s64/subpage_prot.c b/arch/powerpc/mm/book3s64/subpage_prot.c
index 9ba07e55c489..236f0a861ecc 100644
--- a/arch/powerpc/mm/book3s64/subpage_prot.c
+++ b/arch/powerpc/mm/book3s64/subpage_prot.c
@@ -7,7 +7,7 @@
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/types.h>
-#include <linux/mm.h>
+#include <linux/pagewalk.h>
#include <linux/hugetlb.h>
#include <linux/syscalls.h>

diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 39c3a6e3d262..cf80feae970d 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -9,7 +9,7 @@
*/

#include <linux/kernel.h>
-#include <linux/mm.h>
+#include <linux/pagewalk.h>
#include <linux/swap.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 731642e0f5a0..8857da830b86 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -1,5 +1,5 @@
// SPDX-License-Identifier: GPL-2.0
-#include <linux/mm.h>
+#include <linux/pagewalk.h>
#include <linux/vmacache.h>
#include <linux/hugetlb.h>
#include <linux/huge_mm.h>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0334ca97c584..7cf955feb823 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1430,54 +1430,8 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long address,
void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
unsigned long start, unsigned long end);

-/**
- * mm_walk - callbacks for walk_page_range
- * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry
- * this handler should only handle pud_trans_huge() puds.
- * the pmd_entry or pte_entry callbacks will be used for
- * regular PUDs.
- * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
- * this handler is required to be able to handle
- * pmd_trans_huge() pmds. They may simply choose to
- * split_huge_page() instead of handling it explicitly.
- * @pte_entry: if set, called for each non-empty PTE (4th-level) entry
- * @pte_hole: if set, called for each hole at all levels
- * @hugetlb_entry: if set, called for each hugetlb entry
- * @test_walk: caller specific callback function to determine whether
- * we walk over the current vma or not. Returning 0
- * value means "do page table walk over the current vma,"
- * and a negative one means "abort current page table walk
- * right now." 1 means "skip the current vma."
- * @mm: mm_struct representing the target process of page table walk
- * @vma: vma currently walked (NULL if walking outside vmas)
- * @private: private data for callbacks' usage
- *
- * (see the comment on walk_page_range() for more details)
- */
-struct mm_walk {
- int (*pud_entry)(pud_t *pud, unsigned long addr,
- unsigned long next, struct mm_walk *walk);
- int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
- unsigned long next, struct mm_walk *walk);
- int (*pte_entry)(pte_t *pte, unsigned long addr,
- unsigned long next, struct mm_walk *walk);
- int (*pte_hole)(unsigned long addr, unsigned long next,
- struct mm_walk *walk);
- int (*hugetlb_entry)(pte_t *pte, unsigned long hmask,
- unsigned long addr, unsigned long next,
- struct mm_walk *walk);
- int (*test_walk)(unsigned long addr, unsigned long next,
- struct mm_walk *walk);
- struct mm_struct *mm;
- struct vm_area_struct *vma;
- void *private;
-};
-
struct mmu_notifier_range;

-int walk_page_range(unsigned long addr, unsigned long end,
- struct mm_walk *walk);
-int walk_page_vma(struct vm_area_struct *vma, struct mm_walk *walk);
void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
unsigned long end, unsigned long floor, unsigned long ceiling);
int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
diff --git a/include/linux/pagewalk.h b/include/linux/pagewalk.h
new file mode 100644
index 000000000000..df278a94086d
--- /dev/null
+++ b/include/linux/pagewalk.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_PAGEWALK_H
+#define _LINUX_PAGEWALK_H
+
+#include <linux/mm.h>
+
+/**
+ * mm_walk - callbacks for walk_page_range
+ * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry
+ * this handler should only handle pud_trans_huge() puds.
+ * the pmd_entry or pte_entry callbacks will be used for
+ * regular PUDs.
+ * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
+ * this handler is required to be able to handle
+ * pmd_trans_huge() pmds. They may simply choose to
+ * split_huge_page() instead of handling it explicitly.
+ * @pte_entry: if set, called for each non-empty PTE (4th-level) entry
+ * @pte_hole: if set, called for each hole at all levels
+ * @hugetlb_entry: if set, called for each hugetlb entry
+ * @test_walk: caller specific callback function to determine whether
+ * we walk over the current vma or not. Returning 0
+ * value means "do page table walk over the current vma,"
+ * and a negative one means "abort current page table walk
+ * right now." 1 means "skip the current vma."
+ * @mm: mm_struct representing the target process of page table walk
+ * @vma: vma currently walked (NULL if walking outside vmas)
+ * @private: private data for callbacks' usage
+ *
+ * (see the comment on walk_page_range() for more details)
+ */
+struct mm_walk {
+ int (*pud_entry)(pud_t *pud, unsigned long addr,
+ unsigned long next, struct mm_walk *walk);
+ int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
+ unsigned long next, struct mm_walk *walk);
+ int (*pte_entry)(pte_t *pte, unsigned long addr,
+ unsigned long next, struct mm_walk *walk);
+ int (*pte_hole)(unsigned long addr, unsigned long next,
+ struct mm_walk *walk);
+ int (*hugetlb_entry)(pte_t *pte, unsigned long hmask,
+ unsigned long addr, unsigned long next,
+ struct mm_walk *walk);
+ int (*test_walk)(unsigned long addr, unsigned long next,
+ struct mm_walk *walk);
+ struct mm_struct *mm;
+ struct vm_area_struct *vma;
+ void *private;
+};
+
+int walk_page_range(unsigned long addr, unsigned long end,
+ struct mm_walk *walk);
+int walk_page_vma(struct vm_area_struct *vma, struct mm_walk *walk);
+
+#endif /* _LINUX_PAGEWALK_H */
diff --git a/mm/hmm.c b/mm/hmm.c
index 4882b83aeccb..26916ff6c8df 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -8,7 +8,7 @@
* Refer to include/linux/hmm.h for information about heterogeneous memory
* management or HMM for short.
*/
-#include <linux/mm.h>
+#include <linux/pagewalk.h>
#include <linux/hmm.h>
#include <linux/init.h>
#include <linux/rmap.h>
diff --git a/mm/madvise.c b/mm/madvise.c
index 968df3aa069f..80a78bb16782 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -20,6 +20,7 @@
#include <linux/file.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
+#include <linux/pagewalk.h>
#include <linux/swap.h>
#include <linux/swapops.h>
#include <linux/shmem_fs.h>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6f5c0c517c49..4c3af5d71ab1 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -25,7 +25,7 @@
#include <linux/page_counter.h>
#include <linux/memcontrol.h>
#include <linux/cgroup.h>
-#include <linux/mm.h>
+#include <linux/pagewalk.h>
#include <linux/sched/mm.h>
#include <linux/shmem_fs.h>
#include <linux/hugetlb.h>
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 65e0874fce17..3a96def1e796 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -68,7 +68,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/mempolicy.h>
-#include <linux/mm.h>
+#include <linux/pagewalk.h>
#include <linux/highmem.h>
#include <linux/hugetlb.h>
#include <linux/kernel.h>
diff --git a/mm/migrate.c b/mm/migrate.c
index 962cb62c621f..c9c73a35aca7 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -38,6 +38,7 @@
#include <linux/hugetlb.h>
#include <linux/hugetlb_cgroup.h>
#include <linux/gfp.h>
+#include <linux/pagewalk.h>
#include <linux/pfn_t.h>
#include <linux/memremap.h>
#include <linux/userfaultfd_k.h>
diff --git a/mm/mincore.c b/mm/mincore.c
index 4fe91d497436..3b051b6ab3fe 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -10,7 +10,7 @@
*/
#include <linux/pagemap.h>
#include <linux/gfp.h>
-#include <linux/mm.h>
+#include <linux/pagewalk.h>
#include <linux/mman.h>
#include <linux/syscalls.h>
#include <linux/swap.h>
diff --git a/mm/mprotect.c b/mm/mprotect.c
index bf38dfbbb4b4..cc73318dbc25 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -9,7 +9,7 @@
* (C) Copyright 2002 Red Hat Inc, All Rights Reserved
*/

-#include <linux/mm.h>
+#include <linux/pagewalk.h>
#include <linux/hugetlb.h>
#include <linux/shm.h>
#include <linux/mman.h>
diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index c3084ff2569d..8a92a961a2ee 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -1,5 +1,5 @@
// SPDX-License-Identifier: GPL-2.0
-#include <linux/mm.h>
+#include <linux/pagewalk.h>
#include <linux/highmem.h>
#include <linux/sched.h>
#include <linux/hugetlb.h>
--
2.20.1