Commit 6fe6900e authored by Nick Piggin's avatar Nick Piggin Committed by Linus Torvalds

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: default avatarNick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 714b8171
...@@ -40,13 +40,11 @@ struct block2mtd_dev { ...@@ -40,13 +40,11 @@ struct block2mtd_dev {
static LIST_HEAD(blkmtd_device_list); 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_mapping_page(mapping, index, NULL);
return read_cache_page(mapping, index, filler, NULL);
} }
/* erase a specified part of the device */ /* erase a specified part of the device */
static int _block2mtd_erase(struct block2mtd_dev *dev, loff_t to, size_t len) static int _block2mtd_erase(struct block2mtd_dev *dev, loff_t to, size_t len)
{ {
......
...@@ -194,10 +194,7 @@ static struct page *afs_dir_get_page(struct inode *dir, unsigned long index, ...@@ -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); page = read_mapping_page(dir->i_mapping, index, &file);
if (!IS_ERR(page)) { if (!IS_ERR(page)) {
wait_on_page_locked(page);
kmap(page); kmap(page);
if (!PageUptodate(page))
goto fail;
if (!PageChecked(page)) if (!PageChecked(page))
afs_dir_check_page(dir, page); afs_dir_check_page(dir, page);
if (PageError(page)) if (PageError(page))
......
...@@ -68,13 +68,11 @@ int afs_mntpt_check_symlink(struct afs_vnode *vnode, struct key *key) ...@@ -68,13 +68,11 @@ int afs_mntpt_check_symlink(struct afs_vnode *vnode, struct key *key)
} }
ret = -EIO; ret = -EIO;
wait_on_page_locked(page);
buf = kmap(page);
if (!PageUptodate(page))
goto out_free;
if (PageError(page)) if (PageError(page))
goto out_free; goto out_free;
buf = kmap(page);
/* examine the symlink's contents */ /* examine the symlink's contents */
size = vnode->status.size; size = vnode->status.size;
_debug("symlink to %*.*s", (int) size, (int) size, buf); _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) ...@@ -91,8 +89,8 @@ int afs_mntpt_check_symlink(struct afs_vnode *vnode, struct key *key)
ret = 0; ret = 0;
out_free:
kunmap(page); kunmap(page);
out_free:
page_cache_release(page); page_cache_release(page);
out: out:
_leave(" = %d", ret); _leave(" = %d", ret);
...@@ -171,8 +169,7 @@ static struct vfsmount *afs_mntpt_do_automount(struct dentry *mntpt) ...@@ -171,8 +169,7 @@ static struct vfsmount *afs_mntpt_do_automount(struct dentry *mntpt)
} }
ret = -EIO; ret = -EIO;
wait_on_page_locked(page); if (PageError(page))
if (!PageUptodate(page) || PageError(page))
goto error; goto error;
buf = kmap(page); buf = kmap(page);
......
...@@ -180,7 +180,8 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i ...@@ -180,7 +180,8 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i
struct page *page = NULL; struct page *page = NULL;
if (blocknr + i < devsize) { if (blocknr + i < devsize) {
page = read_mapping_page(mapping, blocknr + i, NULL); page = read_mapping_page_async(mapping, blocknr + i,
NULL);
/* synchronous error? */ /* synchronous error? */
if (IS_ERR(page)) if (IS_ERR(page))
page = NULL; page = NULL;
......
...@@ -46,7 +46,6 @@ struct kmem_cache *ecryptfs_lower_page_cache; ...@@ -46,7 +46,6 @@ struct kmem_cache *ecryptfs_lower_page_cache;
*/ */
static struct page *ecryptfs_get1page(struct file *file, int index) static struct page *ecryptfs_get1page(struct file *file, int index)
{ {
struct page *page;
struct dentry *dentry; struct dentry *dentry;
struct inode *inode; struct inode *inode;
struct address_space *mapping; struct address_space *mapping;
...@@ -54,14 +53,7 @@ static struct page *ecryptfs_get1page(struct file *file, int index) ...@@ -54,14 +53,7 @@ static struct page *ecryptfs_get1page(struct file *file, int index)
dentry = file->f_path.dentry; dentry = file->f_path.dentry;
inode = dentry->d_inode; inode = dentry->d_inode;
mapping = inode->i_mapping; mapping = inode->i_mapping;
page = read_cache_page(mapping, index, return read_mapping_page(mapping, index, (void *)file);
(filler_t *)mapping->a_ops->readpage,
(void *)file);
if (IS_ERR(page))
goto out;
wait_on_page_locked(page);
out:
return page;
} }
static static
...@@ -233,7 +225,6 @@ int ecryptfs_do_readpage(struct file *file, struct page *page, ...@@ -233,7 +225,6 @@ int ecryptfs_do_readpage(struct file *file, struct page *page,
ecryptfs_printk(KERN_ERR, "Error reading from page cache\n"); ecryptfs_printk(KERN_ERR, "Error reading from page cache\n");
goto out; goto out;
} }
wait_on_page_locked(lower_page);
page_data = kmap_atomic(page, KM_USER0); page_data = kmap_atomic(page, KM_USER0);
lower_page_data = kmap_atomic(lower_page, KM_USER1); lower_page_data = kmap_atomic(lower_page, KM_USER1);
memcpy(page_data, lower_page_data, PAGE_CACHE_SIZE); memcpy(page_data, lower_page_data, PAGE_CACHE_SIZE);
......
...@@ -161,10 +161,7 @@ static struct page * ext2_get_page(struct inode *dir, unsigned long n) ...@@ -161,10 +161,7 @@ static struct page * ext2_get_page(struct inode *dir, unsigned long n)
struct address_space *mapping = dir->i_mapping; struct address_space *mapping = dir->i_mapping;
struct page *page = read_mapping_page(mapping, n, NULL); struct page *page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) { if (!IS_ERR(page)) {
wait_on_page_locked(page);
kmap(page); kmap(page);
if (!PageUptodate(page))
goto fail;
if (!PageChecked(page)) if (!PageChecked(page))
ext2_check_page(page); ext2_check_page(page);
if (PageError(page)) if (PageError(page))
......
...@@ -74,10 +74,7 @@ vxfs_get_page(struct address_space *mapping, u_long n) ...@@ -74,10 +74,7 @@ vxfs_get_page(struct address_space *mapping, u_long n)
pp = read_mapping_page(mapping, n, NULL); pp = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(pp)) { if (!IS_ERR(pp)) {
wait_on_page_locked(pp);
kmap(pp); kmap(pp);
if (!PageUptodate(pp))
goto fail;
/** if (!PageChecked(pp)) **/ /** if (!PageChecked(pp)) **/
/** vxfs_check_page(pp); **/ /** vxfs_check_page(pp); **/
if (PageError(pp)) if (PageError(pp))
......
...@@ -65,7 +65,6 @@ static struct page * dir_get_page(struct inode *dir, unsigned long n) ...@@ -65,7 +65,6 @@ static struct page * dir_get_page(struct inode *dir, unsigned long n)
struct address_space *mapping = dir->i_mapping; struct address_space *mapping = dir->i_mapping;
struct page *page = read_mapping_page(mapping, n, NULL); struct page *page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) { if (!IS_ERR(page)) {
wait_on_page_locked(page);
kmap(page); kmap(page);
if (!PageUptodate(page)) if (!PageUptodate(page))
goto fail; goto fail;
......
...@@ -2671,19 +2671,9 @@ static char *page_getlink(struct dentry * dentry, struct page **ppage) ...@@ -2671,19 +2671,9 @@ static char *page_getlink(struct dentry * dentry, struct page **ppage)
struct address_space *mapping = dentry->d_inode->i_mapping; struct address_space *mapping = dentry->d_inode->i_mapping;
page = read_mapping_page(mapping, 0, NULL); page = read_mapping_page(mapping, 0, NULL);
if (IS_ERR(page)) if (IS_ERR(page))
goto sync_fail; return (char*)page;
wait_on_page_locked(page);
if (!PageUptodate(page))
goto async_fail;
*ppage = page; *ppage = page;
return kmap(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) int page_readlink(struct dentry *dentry, char __user *buffer, int buflen)
......
...@@ -334,8 +334,6 @@ int find_dirent_page(nfs_readdir_descriptor_t *desc) ...@@ -334,8 +334,6 @@ int find_dirent_page(nfs_readdir_descriptor_t *desc)
status = PTR_ERR(page); status = PTR_ERR(page);
goto out; goto out;
} }
if (!PageUptodate(page))
goto read_error;
/* NOTE: Someone else may have changed the READDIRPLUS flag */ /* NOTE: Someone else may have changed the READDIRPLUS flag */
desc->page = page; desc->page = page;
...@@ -349,9 +347,6 @@ int find_dirent_page(nfs_readdir_descriptor_t *desc) ...@@ -349,9 +347,6 @@ int find_dirent_page(nfs_readdir_descriptor_t *desc)
out: out:
dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __FUNCTION__, status); dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __FUNCTION__, status);
return status; return status;
read_error:
page_cache_release(page);
return -EIO;
} }
/* /*
......
...@@ -61,15 +61,9 @@ static void *nfs_follow_link(struct dentry *dentry, struct nameidata *nd) ...@@ -61,15 +61,9 @@ static void *nfs_follow_link(struct dentry *dentry, struct nameidata *nd)
err = page; err = page;
goto read_failed; goto read_failed;
} }
if (!PageUptodate(page)) {
err = ERR_PTR(-EIO);
goto getlink_read_error;
}
nd_set_link(nd, kmap(page)); nd_set_link(nd, kmap(page));
return page; return page;
getlink_read_error:
page_cache_release(page);
read_failed: read_failed:
nd_set_link(nd, err); nd_set_link(nd, err);
return NULL; return NULL;
......
...@@ -89,9 +89,8 @@ static inline struct page *ntfs_map_page(struct address_space *mapping, ...@@ -89,9 +89,8 @@ static inline struct page *ntfs_map_page(struct address_space *mapping,
struct page *page = read_mapping_page(mapping, index, NULL); struct page *page = read_mapping_page(mapping, index, NULL);
if (!IS_ERR(page)) { if (!IS_ERR(page)) {
wait_on_page_locked(page);
kmap(page); kmap(page);
if (PageUptodate(page) && !PageError(page)) if (!PageError(page))
return page; return page;
ntfs_unmap_page(page); ntfs_unmap_page(page);
return ERR_PTR(-EIO); return ERR_PTR(-EIO);
......
...@@ -2532,14 +2532,7 @@ int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val) ...@@ -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); page = read_mapping_page(mapping, idx, NULL);
if (IS_ERR(page)) { if (IS_ERR(page)) {
ntfs_error(vol->sb, "Failed to read first partial " ntfs_error(vol->sb, "Failed to read first partial "
"page (sync error, index 0x%lx).", idx); "page (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);
return PTR_ERR(page); return PTR_ERR(page);
} }
/* /*
...@@ -2602,14 +2595,7 @@ int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val) ...@@ -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); page = read_mapping_page(mapping, idx, NULL);
if (IS_ERR(page)) { if (IS_ERR(page)) {
ntfs_error(vol->sb, "Failed to read last partial page " ntfs_error(vol->sb, "Failed to read last partial page "
"(sync error, index 0x%lx).", idx); "(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);
return PTR_ERR(page); return PTR_ERR(page);
} }
kaddr = kmap_atomic(page, KM_USER0); kaddr = kmap_atomic(page, KM_USER0);
......
...@@ -236,8 +236,7 @@ static int ntfs_attr_extend_initialized(ntfs_inode *ni, const s64 new_init_size, ...@@ -236,8 +236,7 @@ static int ntfs_attr_extend_initialized(ntfs_inode *ni, const s64 new_init_size,
err = PTR_ERR(page); err = PTR_ERR(page);
goto init_err_out; goto init_err_out;
} }
wait_on_page_locked(page); if (unlikely(PageError(page))) {
if (unlikely(!PageUptodate(page) || PageError(page))) {
page_cache_release(page); page_cache_release(page);
err = -EIO; err = -EIO;
goto init_err_out; goto init_err_out;
......
...@@ -2471,7 +2471,6 @@ static s64 get_nr_free_clusters(ntfs_volume *vol) ...@@ -2471,7 +2471,6 @@ static s64 get_nr_free_clusters(ntfs_volume *vol)
s64 nr_free = vol->nr_clusters; s64 nr_free = vol->nr_clusters;
u32 *kaddr; u32 *kaddr;
struct address_space *mapping = vol->lcnbmp_ino->i_mapping; struct address_space *mapping = vol->lcnbmp_ino->i_mapping;
filler_t *readpage = (filler_t*)mapping->a_ops->readpage;
struct page *page; struct page *page;
pgoff_t index, max_index; pgoff_t index, max_index;
...@@ -2494,24 +2493,14 @@ static s64 get_nr_free_clusters(ntfs_volume *vol) ...@@ -2494,24 +2493,14 @@ static s64 get_nr_free_clusters(ntfs_volume *vol)
* Read the page from page cache, getting it from backing store * Read the page from page cache, getting it from backing store
* if necessary, and increment the use count. * if necessary, and increment the use count.
*/ */
page = read_cache_page(mapping, index, (filler_t*)readpage, page = read_mapping_page(mapping, index, NULL);
NULL);
/* Ignore pages which errored synchronously. */ /* Ignore pages which errored synchronously. */
if (IS_ERR(page)) { if (IS_ERR(page)) {
ntfs_debug("Sync read_cache_page() error. Skipping " ntfs_debug("read_mapping_page() error. Skipping "
"page (index 0x%lx).", index); "page (index 0x%lx).", index);
nr_free -= PAGE_CACHE_SIZE * 8; nr_free -= PAGE_CACHE_SIZE * 8;
continue; 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); kaddr = (u32*)kmap_atomic(page, KM_USER0);
/* /*
* For each 4 bytes, subtract the number of set bits. If this * 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, ...@@ -2562,7 +2551,6 @@ static unsigned long __get_nr_free_mft_records(ntfs_volume *vol,
{ {
u32 *kaddr; u32 *kaddr;
struct address_space *mapping = vol->mftbmp_ino->i_mapping; struct address_space *mapping = vol->mftbmp_ino->i_mapping;
filler_t *readpage = (filler_t*)mapping->a_ops->readpage;
struct page *page; struct page *page;
pgoff_t index; pgoff_t index;
...@@ -2576,24 +2564,14 @@ static unsigned long __get_nr_free_mft_records(ntfs_volume *vol, ...@@ -2576,24 +2564,14 @@ static unsigned long __get_nr_free_mft_records(ntfs_volume *vol,
* Read the page from page cache, getting it from backing store * Read the page from page cache, getting it from backing store
* if necessary, and increment the use count. * if necessary, and increment the use count.
*/ */
page = read_cache_page(mapping, index, (filler_t*)readpage, page = read_mapping_page(mapping, index, NULL);
NULL);
/* Ignore pages which errored synchronously. */ /* Ignore pages which errored synchronously. */
if (IS_ERR(page)) { if (IS_ERR(page)) {
ntfs_debug("Sync read_cache_page() error. Skipping " ntfs_debug("read_mapping_page() error. Skipping "
"page (index 0x%lx).", index); "page (index 0x%lx).", index);
nr_free -= PAGE_CACHE_SIZE * 8; nr_free -= PAGE_CACHE_SIZE * 8;
continue; 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); kaddr = (u32*)kmap_atomic(page, KM_USER0);
/* /*
* For each 4 bytes, subtract the number of set bits. If this * For each 4 bytes, subtract the number of set bits. If this
......
...@@ -67,16 +67,9 @@ static char *ocfs2_page_getlink(struct dentry * dentry, ...@@ -67,16 +67,9 @@ static char *ocfs2_page_getlink(struct dentry * dentry,
page = read_mapping_page(mapping, 0, NULL); page = read_mapping_page(mapping, 0, NULL);
if (IS_ERR(page)) if (IS_ERR(page))
goto sync_fail; goto sync_fail;
wait_on_page_locked(page);
if (!PageUptodate(page))
goto async_fail;
*ppage = page; *ppage = page;
return kmap(page); return kmap(page);
async_fail:
page_cache_release(page);
return ERR_PTR(-EIO);
sync_fail: sync_fail:
return (char*)page; return (char*)page;
} }
......
...@@ -569,9 +569,6 @@ unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p) ...@@ -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)), page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
NULL); NULL);
if (!IS_ERR(page)) { if (!IS_ERR(page)) {
wait_on_page_locked(page);
if (!PageUptodate(page))
goto fail;
if (PageError(page)) if (PageError(page))
goto fail; goto fail;
p->v = page; p->v = page;
......
...@@ -410,11 +410,7 @@ static struct page *reiserfs_get_page(struct inode *dir, unsigned long n) ...@@ -410,11 +410,7 @@ static struct page *reiserfs_get_page(struct inode *dir, unsigned long n)
mapping_set_gfp_mask(mapping, GFP_NOFS); mapping_set_gfp_mask(mapping, GFP_NOFS);
page = read_mapping_page(mapping, n, NULL); page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) { if (!IS_ERR(page)) {
wait_on_page_locked(page);
kmap(page); kmap(page);
if (!PageUptodate(page))
goto fail;
if (PageError(page)) if (PageError(page))
goto fail; goto fail;
} }
......
...@@ -54,17 +54,9 @@ static struct page * dir_get_page(struct inode *dir, unsigned long n) ...@@ -54,17 +54,9 @@ static struct page * dir_get_page(struct inode *dir, unsigned long n)
{ {
struct address_space *mapping = dir->i_mapping; struct address_space *mapping = dir->i_mapping;
struct page *page = read_mapping_page(mapping, n, NULL); struct page *page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) { if (!IS_ERR(page))
wait_on_page_locked(page);
kmap(page); kmap(page);
if (!PageUptodate(page))
goto fail;
}
return page; return page;
fail:
dir_put_page(page);
return ERR_PTR(-EIO);
} }
static int sysv_readdir(struct file * filp, void * dirent, filldir_t filldir) static int sysv_readdir(struct file * filp, void * dirent, filldir_t filldir)
......
...@@ -180,13 +180,9 @@ static void ufs_check_page(struct page *page) ...@@ -180,13 +180,9 @@ static void ufs_check_page(struct page *page)
static struct page *ufs_get_page(struct inode *dir, unsigned long n) static struct page *ufs_get_page(struct inode *dir, unsigned long n)
{ {
struct address_space *mapping = dir->i_mapping; struct address_space *mapping = dir->i_mapping;
struct page *page = read_cache_page(mapping, n, struct page *page = read_mapping_page(mapping, n, NULL);
(filler_t*)mapping->a_ops->readpage, NULL);
if (!IS_ERR(page)) { if (!IS_ERR(page)) {
wait_on_page_locked(page);
kmap(page); kmap(page);
if (!PageUptodate(page))
goto fail;
if (!PageChecked(page)) if (!PageChecked(page))
ufs_check_page(page); ufs_check_page(page);
if (PageError(page)) if (PageError(page))
......
...@@ -251,13 +251,11 @@ struct page *ufs_get_locked_page(struct address_space *mapping, ...@@ -251,13 +251,11 @@ struct page *ufs_get_locked_page(struct address_space *mapping,
page = find_lock_page(mapping, index); page = find_lock_page(mapping, index);
if (!page) { if (!page) {
page = read_cache_page(mapping, index, page = read_mapping_page(mapping, index, NULL);
(filler_t*)mapping->a_ops->readpage,
NULL);
if (IS_ERR(page)) { if (IS_ERR(page)) {
printk(KERN_ERR "ufs_change_blocknr: " 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); mapping->host->i_ino, index);
goto out; goto out;
} }
......
...@@ -95,12 +95,23 @@ static inline struct page *grab_cache_page(struct address_space *mapping, unsign ...@@ -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, extern struct page * grab_cache_page_nowait(struct address_space *mapping,
unsigned long index); 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, extern struct page * read_cache_page(struct address_space *mapping,
unsigned long index, filler_t *filler, unsigned long index, filler_t *filler,
void *data); void *data);
extern int read_cache_pages(struct address_space *mapping, extern int read_cache_pages(struct address_space *mapping,
struct list_head *pages, filler_t *filler, void *data); 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, static inline struct page *read_mapping_page(struct address_space *mapping,
unsigned long index, void *data) unsigned long index, void *data)
{ {
......
...@@ -1726,7 +1726,7 @@ int generic_file_readonly_mmap(struct file * file, struct vm_area_struct * vma) ...@@ -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_mmap);
EXPORT_SYMBOL(generic_file_readonly_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, unsigned long index,
int (*filler)(void *,struct page*), int (*filler)(void *,struct page*),
void *data) void *data)
...@@ -1763,17 +1763,11 @@ static inline struct page *__read_cache_page(struct address_space *mapping, ...@@ -1763,17 +1763,11 @@ static inline struct page *__read_cache_page(struct address_space *mapping,
return page; return page;
} }
/** /*
* read_cache_page - read into page cache, fill it if needed * Same as read_cache_page, but don't wait for page to become unlocked
* @mapping: the page's address_space * after submitting it to the filler.
* @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.
*/ */
struct page *read_cache_page(struct address_space *mapping, struct page *read_cache_page_async(struct address_space *mapping,
unsigned long index, unsigned long index,
int (*filler)(void *,struct page*), int (*filler)(void *,struct page*),
void *data) void *data)
...@@ -1804,6 +1798,39 @@ struct page *read_cache_page(struct address_space *mapping, ...@@ -1804,6 +1798,39 @@ struct page *read_cache_page(struct address_space *mapping,
page_cache_release(page); page_cache_release(page);
page = ERR_PTR(err); 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: out:
return page; return page;
} }
......
...@@ -1531,9 +1531,6 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) ...@@ -1531,9 +1531,6 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags)
error = PTR_ERR(page); error = PTR_ERR(page);
goto bad_swap; goto bad_swap;
} }
wait_on_page_locked(page);
if (!PageUptodate(page))
goto bad_swap;
kmap(page); kmap(page);
swap_header = page_address(page); swap_header = page_address(page);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment