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Diffstat (limited to 'mm/shmem.c')
-rw-r--r--mm/shmem.c101
1 files changed, 53 insertions, 48 deletions
diff --git a/mm/shmem.c b/mm/shmem.c
index 4b5cca167baf..9b17bd4cbc5e 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -181,6 +181,38 @@ static inline void shmem_unacct_blocks(unsigned long flags, long pages)
vm_unacct_memory(pages * VM_ACCT(PAGE_SIZE));
}
+static inline bool shmem_inode_acct_block(struct inode *inode, long pages)
+{
+ struct shmem_inode_info *info = SHMEM_I(inode);
+ struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
+
+ if (shmem_acct_block(info->flags, pages))
+ return false;
+
+ if (sbinfo->max_blocks) {
+ if (percpu_counter_compare(&sbinfo->used_blocks,
+ sbinfo->max_blocks - pages) > 0)
+ goto unacct;
+ percpu_counter_add(&sbinfo->used_blocks, pages);
+ }
+
+ return true;
+
+unacct:
+ shmem_unacct_blocks(info->flags, pages);
+ return false;
+}
+
+static inline void shmem_inode_unacct_blocks(struct inode *inode, long pages)
+{
+ struct shmem_inode_info *info = SHMEM_I(inode);
+ struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
+
+ if (sbinfo->max_blocks)
+ percpu_counter_sub(&sbinfo->used_blocks, pages);
+ shmem_unacct_blocks(info->flags, pages);
+}
+
static const struct super_operations shmem_ops;
static const struct address_space_operations shmem_aops;
static const struct file_operations shmem_file_operations;
@@ -237,61 +269,46 @@ static void shmem_recalc_inode(struct inode *inode)
freed = info->alloced - info->swapped - inode->i_mapping->nrpages;
if (freed > 0) {
- struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
- if (sbinfo->max_blocks)
- percpu_counter_add(&sbinfo->used_blocks, -freed);
info->alloced -= freed;
inode->i_blocks -= freed * BLOCKS_PER_PAGE;
- shmem_unacct_blocks(info->flags, freed);
+ shmem_inode_unacct_blocks(inode, freed);
}
}
bool shmem_charge(struct inode *inode, long pages)
{
struct shmem_inode_info *info = SHMEM_I(inode);
- struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
unsigned long flags;
- if (shmem_acct_block(info->flags, pages))
+ if (!shmem_inode_acct_block(inode, pages))
return false;
+
+ /* nrpages adjustment first, then shmem_recalc_inode() when balanced */
+ inode->i_mapping->nrpages += pages;
+
spin_lock_irqsave(&info->lock, flags);
info->alloced += pages;
inode->i_blocks += pages * BLOCKS_PER_PAGE;
shmem_recalc_inode(inode);
spin_unlock_irqrestore(&info->lock, flags);
- inode->i_mapping->nrpages += pages;
- if (!sbinfo->max_blocks)
- return true;
- if (percpu_counter_compare(&sbinfo->used_blocks,
- sbinfo->max_blocks - pages) > 0) {
- inode->i_mapping->nrpages -= pages;
- spin_lock_irqsave(&info->lock, flags);
- info->alloced -= pages;
- shmem_recalc_inode(inode);
- spin_unlock_irqrestore(&info->lock, flags);
- shmem_unacct_blocks(info->flags, pages);
- return false;
- }
- percpu_counter_add(&sbinfo->used_blocks, pages);
return true;
}
void shmem_uncharge(struct inode *inode, long pages)
{
struct shmem_inode_info *info = SHMEM_I(inode);
- struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
unsigned long flags;
+ /* nrpages adjustment done by __delete_from_page_cache() or caller */
+
spin_lock_irqsave(&info->lock, flags);
info->alloced -= pages;
inode->i_blocks -= pages * BLOCKS_PER_PAGE;
shmem_recalc_inode(inode);
spin_unlock_irqrestore(&info->lock, flags);
- if (sbinfo->max_blocks)
- percpu_counter_sub(&sbinfo->used_blocks, pages);
- shmem_unacct_blocks(info->flags, pages);
+ shmem_inode_unacct_blocks(inode, pages);
}
/*
@@ -1424,9 +1441,10 @@ static struct page *shmem_alloc_page(gfp_t gfp,
}
static struct page *shmem_alloc_and_acct_page(gfp_t gfp,
- struct shmem_inode_info *info, struct shmem_sb_info *sbinfo,
+ struct inode *inode,
pgoff_t index, bool huge)
{
+ struct shmem_inode_info *info = SHMEM_I(inode);
struct page *page;
int nr;
int err = -ENOSPC;
@@ -1435,14 +1453,8 @@ static struct page *shmem_alloc_and_acct_page(gfp_t gfp,
huge = false;
nr = huge ? HPAGE_PMD_NR : 1;
- if (shmem_acct_block(info->flags, nr))
+ if (!shmem_inode_acct_block(inode, nr))
goto failed;
- if (sbinfo->max_blocks) {
- if (percpu_counter_compare(&sbinfo->used_blocks,
- sbinfo->max_blocks - nr) > 0)
- goto unacct;
- percpu_counter_add(&sbinfo->used_blocks, nr);
- }
if (huge)
page = shmem_alloc_hugepage(gfp, info, index);
@@ -1455,10 +1467,7 @@ static struct page *shmem_alloc_and_acct_page(gfp_t gfp,
}
err = -ENOMEM;
- if (sbinfo->max_blocks)
- percpu_counter_add(&sbinfo->used_blocks, -nr);
-unacct:
- shmem_unacct_blocks(info->flags, nr);
+ shmem_inode_unacct_blocks(inode, nr);
failed:
return ERR_PTR(err);
}
@@ -1485,11 +1494,13 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp,
{
struct page *oldpage, *newpage;
struct address_space *swap_mapping;
+ swp_entry_t entry;
pgoff_t swap_index;
int error;
oldpage = *pagep;
- swap_index = page_private(oldpage);
+ entry.val = page_private(oldpage);
+ swap_index = swp_offset(entry);
swap_mapping = page_mapping(oldpage);
/*
@@ -1508,7 +1519,7 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp,
__SetPageLocked(newpage);
__SetPageSwapBacked(newpage);
SetPageUptodate(newpage);
- set_page_private(newpage, swap_index);
+ set_page_private(newpage, entry.val);
SetPageSwapCache(newpage);
/*
@@ -1718,10 +1729,9 @@ repeat:
}
alloc_huge:
- page = shmem_alloc_and_acct_page(gfp, info, sbinfo,
- index, true);
+ page = shmem_alloc_and_acct_page(gfp, inode, index, true);
if (IS_ERR(page)) {
-alloc_nohuge: page = shmem_alloc_and_acct_page(gfp, info, sbinfo,
+alloc_nohuge: page = shmem_alloc_and_acct_page(gfp, inode,
index, false);
}
if (IS_ERR(page)) {
@@ -1843,10 +1853,7 @@ clear:
* Error recovery.
*/
unacct:
- if (sbinfo->max_blocks)
- percpu_counter_sub(&sbinfo->used_blocks,
- 1 << compound_order(page));
- shmem_unacct_blocks(info->flags, 1 << compound_order(page));
+ shmem_inode_unacct_blocks(inode, 1 << compound_order(page));
if (PageTransHuge(page)) {
unlock_page(page);
@@ -2414,9 +2421,7 @@ static loff_t shmem_file_llseek(struct file *file, loff_t offset, int whence)
inode_lock(inode);
/* We're holding i_mutex so we can access i_size directly */
- if (offset < 0)
- offset = -EINVAL;
- else if (offset >= inode->i_size)
+ if (offset < 0 || offset >= inode->i_size)
offset = -ENXIO;
else {
start = offset >> PAGE_SHIFT;
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-19 04:58:46 +0000