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>
diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index dac5b99..0c1e902 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -194,10 +194,7 @@
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 b905ae3..034fcfd 100644
--- a/fs/afs/mntpt.c
+++ b/fs/afs/mntpt.c
@@ -68,13 +68,11 @@
}
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 @@
ret = 0;
-out_free:
kunmap(page);
+out_free:
page_cache_release(page);
out:
_leave(" = %d", ret);
@@ -171,8 +169,7 @@
}
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 facd0c8..3d194a2 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -180,7 +180,8 @@
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 b731b09..0770c4b 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -46,7 +46,6 @@
*/
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 @@
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 @@
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 e89bfc8..1d1e7e3 100644
--- a/fs/ext2/dir.c
+++ b/fs/ext2/dir.c
@@ -161,10 +161,7 @@
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 decac62..ed8f0b0 100644
--- a/fs/freevxfs/vxfs_subr.c
+++ b/fs/freevxfs/vxfs_subr.c
@@ -74,10 +74,7 @@
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 cb4cb57..e207cbe 100644
--- a/fs/minix/dir.c
+++ b/fs/minix/dir.c
@@ -65,7 +65,6 @@
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 880052c..94b2f60 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2671,19 +2671,9 @@
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 e59fd31..625d8e5 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -334,8 +334,6 @@
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 @@
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 f4a0548..bc28213 100644
--- a/fs/nfs/symlink.c
+++ b/fs/nfs/symlink.c
@@ -61,15 +61,9 @@
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 9393f4b..caecc58 100644
--- a/fs/ntfs/aops.h
+++ b/fs/ntfs/aops.h
@@ -89,9 +89,8 @@
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 7659cc1..1c08fef 100644
--- a/fs/ntfs/attrib.c
+++ b/fs/ntfs/attrib.c
@@ -2532,14 +2532,7 @@
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 @@
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 d69c459..dbbac55 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -236,8 +236,7 @@
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 1594c90..2ddde53 100644
--- a/fs/ntfs/super.c
+++ b/fs/ntfs/super.c
@@ -2471,7 +2471,6 @@
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 @@
* 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 @@
{
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;
@@ -2576,24 +2564,14 @@
* 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
diff --git a/fs/ocfs2/symlink.c b/fs/ocfs2/symlink.c
index 40dc1a5..7134007 100644
--- a/fs/ocfs2/symlink.c
+++ b/fs/ocfs2/symlink.c
@@ -67,16 +67,9 @@
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 f01572f..6b9dae3 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -569,9 +569,6 @@
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 2cac562..bf6e582 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -410,11 +410,7 @@
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 ebf7007..e566b38 100644
--- a/fs/sysv/dir.c
+++ b/fs/sysv/dir.c
@@ -54,17 +54,9 @@
{
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 4890ddf..4fb8b2e 100644
--- a/fs/ufs/dir.c
+++ b/fs/ufs/dir.c
@@ -180,13 +180,9 @@
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 1743757..84357f1 100644
--- a/fs/ufs/util.c
+++ b/fs/ufs/util.c
@@ -251,13 +251,11 @@
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;
}
