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Diffstat (limited to 'mm/msync.c')
-rw-r--r--mm/msync.c80
1 files changed, 29 insertions, 51 deletions
diff --git a/mm/msync.c b/mm/msync.c
index d0f5a1bce7c..1b5b6f662dc 100644
--- a/mm/msync.c
+++ b/mm/msync.c
@@ -17,40 +17,43 @@
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
-/*
- * Called with mm->page_table_lock held to protect against other
- * threads/the swapper from ripping pte's out from under us.
- */
-
-static void sync_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
+static void msync_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
unsigned long addr, unsigned long end)
{
pte_t *pte;
+ spinlock_t *ptl;
+ int progress = 0;
- pte = pte_offset_map(pmd, addr);
+again:
+ pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
do {
- unsigned long pfn;
struct page *page;
+ if (progress >= 64) {
+ progress = 0;
+ if (need_resched() || need_lockbreak(ptl))
+ break;
+ }
+ progress++;
if (!pte_present(*pte))
continue;
if (!pte_maybe_dirty(*pte))
continue;
- pfn = pte_pfn(*pte);
- if (!pfn_valid(pfn))
- continue;
- page = pfn_to_page(pfn);
- if (PageReserved(page))
+ page = vm_normal_page(vma, addr, *pte);
+ if (!page)
continue;
-
if (ptep_clear_flush_dirty(vma, addr, pte) ||
page_test_and_clear_dirty(page))
set_page_dirty(page);
+ progress += 3;
} while (pte++, addr += PAGE_SIZE, addr != end);
- pte_unmap(pte - 1);
+ pte_unmap_unlock(pte - 1, ptl);
+ cond_resched();
+ if (addr != end)
+ goto again;
}
-static inline void sync_pmd_range(struct vm_area_struct *vma, pud_t *pud,
+static inline void msync_pmd_range(struct vm_area_struct *vma, pud_t *pud,
unsigned long addr, unsigned long end)
{
pmd_t *pmd;
@@ -61,11 +64,11 @@ static inline void sync_pmd_range(struct vm_area_struct *vma, pud_t *pud,
next = pmd_addr_end(addr, end);
if (pmd_none_or_clear_bad(pmd))
continue;
- sync_pte_range(vma, pmd, addr, next);
+ msync_pte_range(vma, pmd, addr, next);
} while (pmd++, addr = next, addr != end);
}
-static inline void sync_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
+static inline void msync_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
unsigned long addr, unsigned long end)
{
pud_t *pud;
@@ -76,58 +79,33 @@ static inline void sync_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(pud))
continue;
- sync_pmd_range(vma, pud, addr, next);
+ msync_pmd_range(vma, pud, addr, next);
} while (pud++, addr = next, addr != end);
}
-static void sync_page_range(struct vm_area_struct *vma,
+static void msync_page_range(struct vm_area_struct *vma,
unsigned long addr, unsigned long end)
{
- struct mm_struct *mm = vma->vm_mm;
pgd_t *pgd;
unsigned long next;
/* For hugepages we can't go walking the page table normally,
* but that's ok, hugetlbfs is memory based, so we don't need
- * to do anything more on an msync() */
- if (is_vm_hugetlb_page(vma))
+ * to do anything more on an msync().
+ */
+ if (vma->vm_flags & VM_HUGETLB)
return;
BUG_ON(addr >= end);
- pgd = pgd_offset(mm, addr);
+ pgd = pgd_offset(vma->vm_mm, addr);
flush_cache_range(vma, addr, end);
- spin_lock(&mm->page_table_lock);
do {
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
- sync_pud_range(vma, pgd, addr, next);
+ msync_pud_range(vma, pgd, addr, next);
} while (pgd++, addr = next, addr != end);
- spin_unlock(&mm->page_table_lock);
-}
-
-#ifdef CONFIG_PREEMPT
-static inline void filemap_sync(struct vm_area_struct *vma,
- unsigned long addr, unsigned long end)
-{
- const size_t chunk = 64 * 1024; /* bytes */
- unsigned long next;
-
- do {
- next = addr + chunk;
- if (next > end || next < addr)
- next = end;
- sync_page_range(vma, addr, next);
- cond_resched();
- } while (addr = next, addr != end);
-}
-#else
-static inline void filemap_sync(struct vm_area_struct *vma,
- unsigned long addr, unsigned long end)
-{
- sync_page_range(vma, addr, end);
}
-#endif
/*
* MS_SYNC syncs the entire file - including mappings.
@@ -150,7 +128,7 @@ static int msync_interval(struct vm_area_struct *vma,
return -EBUSY;
if (file && (vma->vm_flags & VM_SHARED)) {
- filemap_sync(vma, addr, end);
+ msync_page_range(vma, addr, end);
if (flags & MS_SYNC) {
struct address_space *mapping = file->f_mapping;