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authorNick Piggin <npiggin@suse.de>2007-05-06 14:49:04 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-05-07 12:12:51 -0700
commit6fe6900e1e5b6fa9e5c59aa5061f244fe3f467e2 (patch)
tree8bbfe5072279227cc50a941ad4813908082426a1
parent714b8171af9c930a59a0da8f6fe50518e70ab035 (diff)
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mm: make read_cache_page synchronous
Ensure pages are uptodate after returning from read_cache_page, which allows us to cut out most of the filesystem-internal PageUptodate calls. I didn't have a great look down the call chains, but this appears to fixes 7 possible use-before uptodate in hfs, 2 in hfsplus, 1 in jfs, a few in ecryptfs, 1 in jffs2, and a possible cleared data overwritten with readpage in block2mtd. All depending on whether the filler is async and/or can return with a !uptodate page. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--drivers/mtd/devices/block2mtd.c6
-rw-r--r--fs/afs/dir.c3
-rw-r--r--fs/afs/mntpt.c11
-rw-r--r--fs/cramfs/inode.c3
-rw-r--r--fs/ecryptfs/mmap.c11
-rw-r--r--fs/ext2/dir.c3
-rw-r--r--fs/freevxfs/vxfs_subr.c3
-rw-r--r--fs/minix/dir.c1
-rw-r--r--fs/namei.c12
-rw-r--r--fs/nfs/dir.c5
-rw-r--r--fs/nfs/symlink.c6
-rw-r--r--fs/ntfs/aops.h3
-rw-r--r--fs/ntfs/attrib.c18
-rw-r--r--fs/ntfs/file.c3
-rw-r--r--fs/ntfs/super.c30
-rw-r--r--fs/ocfs2/symlink.c7
-rw-r--r--fs/partitions/check.c3
-rw-r--r--fs/reiserfs/xattr.c4
-rw-r--r--fs/sysv/dir.c10
-rw-r--r--fs/ufs/dir.c6
-rw-r--r--fs/ufs/util.c6
-rw-r--r--include/linux/pagemap.h11
-rw-r--r--mm/filemap.c49
-rw-r--r--mm/swapfile.c3
24 files changed, 71 insertions, 146 deletions
diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c
index ce47544dc12..fc4cc8ba9e2 100644
--- a/drivers/mtd/devices/block2mtd.c
+++ b/drivers/mtd/devices/block2mtd.c
@@ -40,13 +40,11 @@ struct block2mtd_dev {
static LIST_HEAD(blkmtd_device_list);
-static struct page* page_read(struct address_space *mapping, int index)
+static struct page *page_read(struct address_space *mapping, int index)
{
- filler_t *filler = (filler_t*)mapping->a_ops->readpage;
- return read_cache_page(mapping, index, filler, NULL);
+ return read_mapping_page(mapping, index, NULL);
}
-
/* erase a specified part of the device */
static int _block2mtd_erase(struct block2mtd_dev *dev, loff_t to, size_t len)
{
diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index dac5b990c0c..0c1e902f17a 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -194,10 +194,7 @@ static struct page *afs_dir_get_page(struct inode *dir, unsigned long index,
page = read_mapping_page(dir->i_mapping, index, &file);
if (!IS_ERR(page)) {
- wait_on_page_locked(page);
kmap(page);
- if (!PageUptodate(page))
- goto fail;
if (!PageChecked(page))
afs_dir_check_page(dir, page);
if (PageError(page))
diff --git a/fs/afs/mntpt.c b/fs/afs/mntpt.c
index b905ae37f91..034fcfd4e33 100644
--- a/fs/afs/mntpt.c
+++ b/fs/afs/mntpt.c
@@ -68,13 +68,11 @@ int afs_mntpt_check_symlink(struct afs_vnode *vnode, struct key *key)
}
ret = -EIO;
- wait_on_page_locked(page);
- buf = kmap(page);
- if (!PageUptodate(page))
- goto out_free;
if (PageError(page))
goto out_free;
+ buf = kmap(page);
+
/* examine the symlink's contents */
size = vnode->status.size;
_debug("symlink to %*.*s", (int) size, (int) size, buf);
@@ -91,8 +89,8 @@ int afs_mntpt_check_symlink(struct afs_vnode *vnode, struct key *key)
ret = 0;
-out_free:
kunmap(page);
+out_free:
page_cache_release(page);
out:
_leave(" = %d", ret);
@@ -171,8 +169,7 @@ static struct vfsmount *afs_mntpt_do_automount(struct dentry *mntpt)
}
ret = -EIO;
- wait_on_page_locked(page);
- if (!PageUptodate(page) || PageError(page))
+ if (PageError(page))
goto error;
buf = kmap(page);
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index facd0c89be8..3d194a2be3f 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -180,7 +180,8 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i
struct page *page = NULL;
if (blocknr + i < devsize) {
- page = read_mapping_page(mapping, blocknr + i, NULL);
+ page = read_mapping_page_async(mapping, blocknr + i,
+ NULL);
/* synchronous error? */
if (IS_ERR(page))
page = NULL;
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index b731b09499c..0770c4b66f5 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -46,7 +46,6 @@ struct kmem_cache *ecryptfs_lower_page_cache;
*/
static struct page *ecryptfs_get1page(struct file *file, int index)
{
- struct page *page;
struct dentry *dentry;
struct inode *inode;
struct address_space *mapping;
@@ -54,14 +53,7 @@ static struct page *ecryptfs_get1page(struct file *file, int index)
dentry = file->f_path.dentry;
inode = dentry->d_inode;
mapping = inode->i_mapping;
- page = read_cache_page(mapping, index,
- (filler_t *)mapping->a_ops->readpage,
- (void *)file);
- if (IS_ERR(page))
- goto out;
- wait_on_page_locked(page);
-out:
- return page;
+ return read_mapping_page(mapping, index, (void *)file);
}
static
@@ -233,7 +225,6 @@ int ecryptfs_do_readpage(struct file *file, struct page *page,
ecryptfs_printk(KERN_ERR, "Error reading from page cache\n");
goto out;
}
- wait_on_page_locked(lower_page);
page_data = kmap_atomic(page, KM_USER0);
lower_page_data = kmap_atomic(lower_page, KM_USER1);
memcpy(page_data, lower_page_data, PAGE_CACHE_SIZE);
diff --git a/fs/ext2/dir.c b/fs/ext2/dir.c
index e89bfc8cf95..1d1e7e30d70 100644
--- a/fs/ext2/dir.c
+++ b/fs/ext2/dir.c
@@ -161,10 +161,7 @@ static struct page * ext2_get_page(struct inode *dir, unsigned long n)
struct address_space *mapping = dir->i_mapping;
struct page *page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) {
- wait_on_page_locked(page);
kmap(page);
- if (!PageUptodate(page))
- goto fail;
if (!PageChecked(page))
ext2_check_page(page);
if (PageError(page))
diff --git a/fs/freevxfs/vxfs_subr.c b/fs/freevxfs/vxfs_subr.c
index decac62efe5..ed8f0b0dd88 100644
--- a/fs/freevxfs/vxfs_subr.c
+++ b/fs/freevxfs/vxfs_subr.c
@@ -74,10 +74,7 @@ vxfs_get_page(struct address_space *mapping, u_long n)
pp = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(pp)) {
- wait_on_page_locked(pp);
kmap(pp);
- if (!PageUptodate(pp))
- goto fail;
/** if (!PageChecked(pp)) **/
/** vxfs_check_page(pp); **/
if (PageError(pp))
diff --git a/fs/minix/dir.c b/fs/minix/dir.c
index cb4cb571fdd..e207cbe7095 100644
--- a/fs/minix/dir.c
+++ b/fs/minix/dir.c
@@ -65,7 +65,6 @@ static struct page * dir_get_page(struct inode *dir, unsigned long n)
struct address_space *mapping = dir->i_mapping;
struct page *page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) {
- wait_on_page_locked(page);
kmap(page);
if (!PageUptodate(page))
goto fail;
diff --git a/fs/namei.c b/fs/namei.c
index 880052cadbc..94b2f60aec2 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2671,19 +2671,9 @@ static char *page_getlink(struct dentry * dentry, struct page **ppage)
struct address_space *mapping = dentry->d_inode->i_mapping;
page = read_mapping_page(mapping, 0, NULL);
if (IS_ERR(page))
- goto sync_fail;
- wait_on_page_locked(page);
- if (!PageUptodate(page))
- goto async_fail;
+ return (char*)page;
*ppage = page;
return kmap(page);
-
-async_fail:
- page_cache_release(page);
- return ERR_PTR(-EIO);
-
-sync_fail:
- return (char*)page;
}
int page_readlink(struct dentry *dentry, char __user *buffer, int buflen)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index e59fd31c9a2..625d8e5fb39 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -334,8 +334,6 @@ int find_dirent_page(nfs_readdir_descriptor_t *desc)
status = PTR_ERR(page);
goto out;
}
- if (!PageUptodate(page))
- goto read_error;
/* NOTE: Someone else may have changed the READDIRPLUS flag */
desc->page = page;
@@ -349,9 +347,6 @@ int find_dirent_page(nfs_readdir_descriptor_t *desc)
out:
dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __FUNCTION__, status);
return status;
- read_error:
- page_cache_release(page);
- return -EIO;
}
/*
diff --git a/fs/nfs/symlink.c b/fs/nfs/symlink.c
index f4a0548b9ce..bc2821331c2 100644
--- a/fs/nfs/symlink.c
+++ b/fs/nfs/symlink.c
@@ -61,15 +61,9 @@ static void *nfs_follow_link(struct dentry *dentry, struct nameidata *nd)
err = page;
goto read_failed;
}
- if (!PageUptodate(page)) {
- err = ERR_PTR(-EIO);
- goto getlink_read_error;
- }
nd_set_link(nd, kmap(page));
return page;
-getlink_read_error:
- page_cache_release(page);
read_failed:
nd_set_link(nd, err);
return NULL;
diff --git a/fs/ntfs/aops.h b/fs/ntfs/aops.h
index 9393f4b1e29..caecc58f529 100644
--- a/fs/ntfs/aops.h
+++ b/fs/ntfs/aops.h
@@ -89,9 +89,8 @@ static inline struct page *ntfs_map_page(struct address_space *mapping,
struct page *page = read_mapping_page(mapping, index, NULL);
if (!IS_ERR(page)) {
- wait_on_page_locked(page);
kmap(page);
- if (PageUptodate(page) && !PageError(page))
+ if (!PageError(page))
return page;
ntfs_unmap_page(page);
return ERR_PTR(-EIO);
diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c
index 7659cc19299..1c08fefe487 100644
--- a/fs/ntfs/attrib.c
+++ b/fs/ntfs/attrib.c
@@ -2532,14 +2532,7 @@ int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val)
page = read_mapping_page(mapping, idx, NULL);
if (IS_ERR(page)) {
ntfs_error(vol->sb, "Failed to read first partial "
- "page (sync error, index 0x%lx).", idx);
- return PTR_ERR(page);
- }
- wait_on_page_locked(page);
- if (unlikely(!PageUptodate(page))) {
- ntfs_error(vol->sb, "Failed to read first partial page "
- "(async error, index 0x%lx).", idx);
- page_cache_release(page);
+ "page (error, index 0x%lx).", idx);
return PTR_ERR(page);
}
/*
@@ -2602,14 +2595,7 @@ int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val)
page = read_mapping_page(mapping, idx, NULL);
if (IS_ERR(page)) {
ntfs_error(vol->sb, "Failed to read last partial page "
- "(sync error, index 0x%lx).", idx);
- return PTR_ERR(page);
- }
- wait_on_page_locked(page);
- if (unlikely(!PageUptodate(page))) {
- ntfs_error(vol->sb, "Failed to read last partial page "
- "(async error, index 0x%lx).", idx);
- page_cache_release(page);
+ "(error, index 0x%lx).", idx);
return PTR_ERR(page);
}
kaddr = kmap_atomic(page, KM_USER0);
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index d69c4595ccd..dbbac559310 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -236,8 +236,7 @@ do_non_resident_extend:
err = PTR_ERR(page);
goto init_err_out;
}
- wait_on_page_locked(page);
- if (unlikely(!PageUptodate(page) || PageError(page))) {
+ if (unlikely(PageError(page))) {
page_cache_release(page);
err = -EIO;
goto init_err_out;
diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
index 1594c90b716..2ddde534db0 100644
--- a/fs/ntfs/super.c
+++ b/fs/ntfs/super.c
@@ -2471,7 +2471,6 @@ static s64 get_nr_free_clusters(ntfs_volume *vol)
s64 nr_free = vol->nr_clusters;
u32 *kaddr;
struct address_space *mapping = vol->lcnbmp_ino->i_mapping;
- filler_t *readpage = (filler_t*)mapping->a_ops->readpage;
struct page *page;
pgoff_t index, max_index;
@@ -2494,24 +2493,14 @@ static s64 get_nr_free_clusters(ntfs_volume *vol)
* Read the page from page cache, getting it from backing store
* if necessary, and increment the use count.
*/
- page = read_cache_page(mapping, index, (filler_t*)readpage,
- NULL);
+ page = read_mapping_page(mapping, index, NULL);
/* Ignore pages which errored synchronously. */
if (IS_ERR(page)) {
- ntfs_debug("Sync read_cache_page() error. Skipping "
+ ntfs_debug("read_mapping_page() error. Skipping "
"page (index 0x%lx).", index);
nr_free -= PAGE_CACHE_SIZE * 8;
continue;
}
- wait_on_page_locked(page);
- /* Ignore pages which errored asynchronously. */
- if (!PageUptodate(page)) {
- ntfs_debug("Async read_cache_page() error. Skipping "
- "page (index 0x%lx).", index);
- page_cache_release(page);
- nr_free -= PAGE_CACHE_SIZE * 8;
- continue;
- }
kaddr = (u32*)kmap_atomic(page, KM_USER0);
/*
* For each 4 bytes, subtract the number of set bits. If this
@@ -2562,7 +2551,6 @@ static unsigned long __get_nr_free_mft_records(ntfs_volume *vol,
{
u32 *kaddr;
struct address_space *mapping = vol->mftbmp_ino->i_mapping;
- filler_t *readpage = (filler_t*)mapping->a_ops->readpage;
struct page *page;
pgoff_t index;
@@ -2576,21 +2564,11 @@ static unsigned long __get_nr_free_mft_records(ntfs_volume *vol,
* Read the page from page cache, getting it from backing store
* if necessary, and increment the use count.
*/
- page = read_cache_page(mapping, index, (filler_t*)readpage,
- NULL);
+ page = read_mapping_page(mapping, index, NULL);
/* Ignore pages which errored synchronously. */
if (IS_ERR(page)) {
- ntfs_debug("Sync read_cache_page() error. Skipping "
- "page (index 0x%lx).", index);
- nr_free -= PAGE_CACHE_SIZE * 8;
- continue;
- }
- wait_on_page_locked(page);
- /* Ignore pages which errored asynchronously. */
- if (!PageUptodate(page)) {
- ntfs_debug("Async read_cache_page() error. Skipping "
+ ntfs_debug("read_mapping_page() error. Skipping "
"page (index 0x%lx).", index);
- page_cache_release(page);
nr_free -= PAGE_CACHE_SIZE * 8;
continue;
}
diff --git a/fs/ocfs2/symlink.c b/fs/ocfs2/symlink.c
index 40dc1a51f4a..7134007ba22 100644
--- a/fs/ocfs2/symlink.c
+++ b/fs/ocfs2/symlink.c
@@ -67,16 +67,9 @@ static char *ocfs2_page_getlink(struct dentry * dentry,
page = read_mapping_page(mapping, 0, NULL);
if (IS_ERR(page))
goto sync_fail;
- wait_on_page_locked(page);
- if (!PageUptodate(page))
- goto async_fail;
*ppage = page;
return kmap(page);
-async_fail:
- page_cache_release(page);
- return ERR_PTR(-EIO);
-
sync_fail:
return (char*)page;
}
diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index f01572fca02..6b9dae3f0e6 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -569,9 +569,6 @@ unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
NULL);
if (!IS_ERR(page)) {
- wait_on_page_locked(page);
- if (!PageUptodate(page))
- goto fail;
if (PageError(page))
goto fail;
p->v = page;
diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
index 2cac56210e2..bf6e5821453 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -410,11 +410,7 @@ static struct page *reiserfs_get_page(struct inode *dir, unsigned long n)
mapping_set_gfp_mask(mapping, GFP_NOFS);
page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) {
- wait_on_page_locked(page);
kmap(page);
- if (!PageUptodate(page))
- goto fail;
-
if (PageError(page))
goto fail;
}
diff --git a/fs/sysv/dir.c b/fs/sysv/dir.c
index ebf7007fa16..e566b387fcf 100644
--- a/fs/sysv/dir.c
+++ b/fs/sysv/dir.c
@@ -54,17 +54,9 @@ static struct page * dir_get_page(struct inode *dir, unsigned long n)
{
struct address_space *mapping = dir->i_mapping;
struct page *page = read_mapping_page(mapping, n, NULL);
- if (!IS_ERR(page)) {
- wait_on_page_locked(page);
+ if (!IS_ERR(page))
kmap(page);
- if (!PageUptodate(page))
- goto fail;
- }
return page;
-
-fail:
- dir_put_page(page);
- return ERR_PTR(-EIO);
}
static int sysv_readdir(struct file * filp, void * dirent, filldir_t filldir)
diff --git a/fs/ufs/dir.c b/fs/ufs/dir.c
index 4890ddf1518..4fb8b2e077e 100644
--- a/fs/ufs/dir.c
+++ b/fs/ufs/dir.c
@@ -180,13 +180,9 @@ fail:
static struct page *ufs_get_page(struct inode *dir, unsigned long n)
{
struct address_space *mapping = dir->i_mapping;
- struct page *page = read_cache_page(mapping, n,
- (filler_t*)mapping->a_ops->readpage, NULL);
+ struct page *page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) {
- wait_on_page_locked(page);
kmap(page);
- if (!PageUptodate(page))
- goto fail;
if (!PageChecked(page))
ufs_check_page(page);
if (PageError(page))
diff --git a/fs/ufs/util.c b/fs/ufs/util.c
index 17437574f79..84357f1ff0e 100644
--- a/fs/ufs/util.c
+++ b/fs/ufs/util.c
@@ -251,13 +251,11 @@ struct page *ufs_get_locked_page(struct address_space *mapping,
page = find_lock_page(mapping, index);
if (!page) {
- page = read_cache_page(mapping, index,
- (filler_t*)mapping->a_ops->readpage,
- NULL);
+ page = read_mapping_page(mapping, index, NULL);
if (IS_ERR(page)) {
printk(KERN_ERR "ufs_change_blocknr: "
- "read_cache_page error: ino %lu, index: %lu\n",
+ "read_mapping_page error: ino %lu, index: %lu\n",
mapping->host->i_ino, index);
goto out;
}
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 7a8dcb82a69..b4def5e083e 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -95,12 +95,23 @@ static inline struct page *grab_cache_page(struct address_space *mapping, unsign
extern struct page * grab_cache_page_nowait(struct address_space *mapping,
unsigned long index);
+extern struct page * read_cache_page_async(struct address_space *mapping,
+ unsigned long index, filler_t *filler,
+ void *data);
extern struct page * read_cache_page(struct address_space *mapping,
unsigned long index, filler_t *filler,
void *data);
extern int read_cache_pages(struct address_space *mapping,
struct list_head *pages, filler_t *filler, void *data);
+static inline struct page *read_mapping_page_async(
+ struct address_space *mapping,
+ unsigned long index, void *data)
+{
+ filler_t *filler = (filler_t *)mapping->a_ops->readpage;
+ return read_cache_page_async(mapping, index, filler, data);
+}
+
static inline struct page *read_mapping_page(struct address_space *mapping,
unsigned long index, void *data)
{
diff --git a/mm/filemap.c b/mm/filemap.c
index 5dfc093ceb3..070e7547d5b 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1726,7 +1726,7 @@ int generic_file_readonly_mmap(struct file * file, struct vm_area_struct * vma)
EXPORT_SYMBOL(generic_file_mmap);
EXPORT_SYMBOL(generic_file_readonly_mmap);
-static inline struct page *__read_cache_page(struct address_space *mapping,
+static struct page *__read_cache_page(struct address_space *mapping,
unsigned long index,
int (*filler)(void *,struct page*),
void *data)
@@ -1763,17 +1763,11 @@ repeat:
return page;
}
-/**
- * read_cache_page - read into page cache, fill it if needed
- * @mapping: the page's address_space
- * @index: the page index
- * @filler: function to perform the read
- * @data: destination for read data
- *
- * Read into the page cache. If a page already exists,
- * and PageUptodate() is not set, try to fill the page.
+/*
+ * Same as read_cache_page, but don't wait for page to become unlocked
+ * after submitting it to the filler.
*/
-struct page *read_cache_page(struct address_space *mapping,
+struct page *read_cache_page_async(struct address_space *mapping,
unsigned long index,
int (*filler)(void *,struct page*),
void *data)
@@ -1805,6 +1799,39 @@ retry:
page = ERR_PTR(err);
}
out:
+ mark_page_accessed(page);
+ return page;
+}
+EXPORT_SYMBOL(read_cache_page_async);
+
+/**
+ * read_cache_page - read into page cache, fill it if needed
+ * @mapping: the page's address_space
+ * @index: the page index
+ * @filler: function to perform the read
+ * @data: destination for read data
+ *
+ * Read into the page cache. If a page already exists, and PageUptodate() is
+ * not set, try to fill the page then wait for it to become unlocked.
+ *
+ * If the page does not get brought uptodate, return -EIO.
+ */
+struct page *read_cache_page(struct address_space *mapping,
+ unsigned long index,
+ int (*filler)(void *,struct page*),
+ void *data)
+{
+ struct page *page;
+
+ page = read_cache_page_async(mapping, index, filler, data);
+ if (IS_ERR(page))
+ goto out;
+ wait_on_page_locked(page);
+ if (!PageUptodate(page)) {
+ page_cache_release(page);
+ page = ERR_PTR(-EIO);
+ }
+ out:
return page;
}
EXPORT_SYMBOL(read_cache_page);
diff --git a/mm/swapfile.c b/mm/swapfile.c
index a2d9bb4e80d..acc172cbe3a 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1531,9 +1531,6 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags)
error = PTR_ERR(page);
goto bad_swap;
}
- wait_on_page_locked(page);
- if (!PageUptodate(page))
- goto bad_swap;
kmap(page);
swap_header = page_address(page);