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Diffstat (limited to 'mm/memory.c')
-rw-r--r--mm/memory.c36
1 files changed, 23 insertions, 13 deletions
diff --git a/mm/memory.c b/mm/memory.c
index b5a4aadd961a..bf6100236e62 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1110,23 +1110,29 @@ static int zeromap_pte_range(struct mm_struct *mm, pmd_t *pmd,
{
pte_t *pte;
spinlock_t *ptl;
+ int err = 0;
pte = pte_alloc_map_lock(mm, pmd, addr, &ptl);
if (!pte)
- return -ENOMEM;
+ return -EAGAIN;
arch_enter_lazy_mmu_mode();
do {
struct page *page = ZERO_PAGE(addr);
pte_t zero_pte = pte_wrprotect(mk_pte(page, prot));
+
+ if (unlikely(!pte_none(*pte))) {
+ err = -EEXIST;
+ pte++;
+ break;
+ }
page_cache_get(page);
page_add_file_rmap(page);
inc_mm_counter(mm, file_rss);
- BUG_ON(!pte_none(*pte));
set_pte_at(mm, addr, pte, zero_pte);
} while (pte++, addr += PAGE_SIZE, addr != end);
arch_leave_lazy_mmu_mode();
pte_unmap_unlock(pte - 1, ptl);
- return 0;
+ return err;
}
static inline int zeromap_pmd_range(struct mm_struct *mm, pud_t *pud,
@@ -1134,16 +1140,18 @@ static inline int zeromap_pmd_range(struct mm_struct *mm, pud_t *pud,
{
pmd_t *pmd;
unsigned long next;
+ int err;
pmd = pmd_alloc(mm, pud, addr);
if (!pmd)
- return -ENOMEM;
+ return -EAGAIN;
do {
next = pmd_addr_end(addr, end);
- if (zeromap_pte_range(mm, pmd, addr, next, prot))
- return -ENOMEM;
+ err = zeromap_pte_range(mm, pmd, addr, next, prot);
+ if (err)
+ break;
} while (pmd++, addr = next, addr != end);
- return 0;
+ return err;
}
static inline int zeromap_pud_range(struct mm_struct *mm, pgd_t *pgd,
@@ -1151,16 +1159,18 @@ static inline int zeromap_pud_range(struct mm_struct *mm, pgd_t *pgd,
{
pud_t *pud;
unsigned long next;
+ int err;
pud = pud_alloc(mm, pgd, addr);
if (!pud)
- return -ENOMEM;
+ return -EAGAIN;
do {
next = pud_addr_end(addr, end);
- if (zeromap_pmd_range(mm, pud, addr, next, prot))
- return -ENOMEM;
+ err = zeromap_pmd_range(mm, pud, addr, next, prot);
+ if (err)
+ break;
} while (pud++, addr = next, addr != end);
- return 0;
+ return err;
}
int zeromap_page_range(struct vm_area_struct *vma,
@@ -1452,6 +1462,7 @@ static inline void cow_user_page(struct page *dst, struct page *src, unsigned lo
if (__copy_from_user_inatomic(kaddr, uaddr, PAGE_SIZE))
memset(kaddr, 0, PAGE_SIZE);
kunmap_atomic(kaddr, KM_USER0);
+ flush_dcache_page(dst);
return;
}
@@ -1901,7 +1912,6 @@ int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end)
return 0;
}
-EXPORT_UNUSED_SYMBOL(vmtruncate_range); /* June 2006 */
/**
* swapin_readahead - swap in pages in hope we need them soon
@@ -1990,6 +2000,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
delayacct_set_flag(DELAYACCT_PF_SWAPIN);
page = lookup_swap_cache(entry);
if (!page) {
+ grab_swap_token(); /* Contend for token _before_ read-in */
swapin_readahead(entry, address, vma);
page = read_swap_cache_async(entry, vma, address);
if (!page) {
@@ -2007,7 +2018,6 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
/* Had to read the page from swap area: Major fault */
ret = VM_FAULT_MAJOR;
count_vm_event(PGMAJFAULT);
- grab_swap_token();
}
delayacct_clear_flag(DELAYACCT_PF_SWAPIN);