Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
[PATCH] NFS: Fix races in nfs_revalidate_mapping()
Prevent the call to invalidate_inode_pages2() from racing with file writes
by taking the inode->i_mutex across the page cache flush and invalidate.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
authored by
Trond Myklebust
and committed by
Linus Torvalds
717d44e8
bde8f00c
+72
-32
+1
-1
fs/nfs/dir.c
+1
-1
fs/nfs/dir.c
+67
-30
fs/nfs/inode.c
+67
-30
fs/nfs/inode.c
···
665
665
return __nfs_revalidate_inode(server, inode);
666
666
}
667
667
668
+
static int nfs_invalidate_mapping_nolock(struct inode *inode, struct address_space *mapping)
669
+
{
670
+
struct nfs_inode *nfsi = NFS_I(inode);
671
+
672
+
if (mapping->nrpages != 0) {
673
+
int ret = invalidate_inode_pages2(mapping);
674
+
if (ret < 0)
675
+
return ret;
676
+
}
677
+
spin_lock(&inode->i_lock);
678
+
nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
679
+
if (S_ISDIR(inode->i_mode)) {
680
+
memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
681
+
/* This ensures we revalidate child dentries */
682
+
nfsi->cache_change_attribute = jiffies;
683
+
}
684
+
spin_unlock(&inode->i_lock);
685
+
nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
686
+
dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n",
687
+
inode->i_sb->s_id, (long long)NFS_FILEID(inode));
688
+
return 0;
689
+
}
690
+
691
+
static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
692
+
{
693
+
int ret = 0;
694
+
695
+
mutex_lock(&inode->i_mutex);
696
+
if (NFS_I(inode)->cache_validity & NFS_INO_INVALID_DATA) {
697
+
ret = nfs_sync_mapping(mapping);
698
+
if (ret == 0)
699
+
ret = nfs_invalidate_mapping_nolock(inode, mapping);
700
+
}
701
+
mutex_unlock(&inode->i_mutex);
702
+
return ret;
703
+
}
704
+
705
+
/**
706
+
* nfs_revalidate_mapping_nolock - Revalidate the pagecache
707
+
* @inode - pointer to host inode
708
+
* @mapping - pointer to mapping
709
+
*/
710
+
int nfs_revalidate_mapping_nolock(struct inode *inode, struct address_space *mapping)
711
+
{
712
+
struct nfs_inode *nfsi = NFS_I(inode);
713
+
int ret = 0;
714
+
715
+
if ((nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
716
+
|| nfs_attribute_timeout(inode) || NFS_STALE(inode)) {
717
+
ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
718
+
if (ret < 0)
719
+
goto out;
720
+
}
721
+
if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
722
+
ret = nfs_invalidate_mapping_nolock(inode, mapping);
723
+
out:
724
+
return ret;
725
+
}
726
+
668
727
/**
669
728
* nfs_revalidate_mapping - Revalidate the pagecache
670
729
* @inode - pointer to host inode
671
730
* @mapping - pointer to mapping
731
+
*
732
+
* This version of the function will take the inode->i_mutex and attempt to
733
+
* flush out all dirty data if it needs to invalidate the page cache.
672
734
*/
673
735
int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
674
736
{
675
737
struct nfs_inode *nfsi = NFS_I(inode);
676
738
int ret = 0;
677
739
678
-
if (NFS_STALE(inode))
679
-
ret = -ESTALE;
680
740
if ((nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
681
-
|| nfs_attribute_timeout(inode))
741
+
|| nfs_attribute_timeout(inode) || NFS_STALE(inode)) {
682
742
ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
683
-
if (ret < 0)
684
-
goto out;
685
-
686
-
if (nfsi->cache_validity & NFS_INO_INVALID_DATA) {
687
-
if (mapping->nrpages != 0) {
688
-
if (S_ISREG(inode->i_mode)) {
689
-
ret = nfs_sync_mapping(mapping);
690
-
if (ret < 0)
691
-
goto out;
692
-
}
693
-
ret = invalidate_inode_pages2(mapping);
694
-
if (ret < 0)
695
-
goto out;
696
-
}
697
-
spin_lock(&inode->i_lock);
698
-
nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
699
-
if (S_ISDIR(inode->i_mode)) {
700
-
memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
701
-
/* This ensures we revalidate child dentries */
702
-
nfsi->cache_change_attribute = jiffies;
703
-
}
704
-
spin_unlock(&inode->i_lock);
705
-
706
-
nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
707
-
dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n",
708
-
inode->i_sb->s_id,
709
-
(long long)NFS_FILEID(inode));
743
+
if (ret < 0)
744
+
goto out;
710
745
}
746
+
if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
747
+
ret = nfs_invalidate_mapping(inode, mapping);
711
748
out:
712
749
return ret;
713
750
}
+3
-1
fs/nfs/symlink.c
+3
-1
fs/nfs/symlink.c
···
50
50
{
51
51
struct inode *inode = dentry->d_inode;
52
52
struct page *page;
53
-
void *err = ERR_PTR(nfs_revalidate_mapping(inode, inode->i_mapping));
53
+
void *err;
54
+
55
+
err = ERR_PTR(nfs_revalidate_mapping_nolock(inode, inode->i_mapping));
54
56
if (err)
55
57
goto read_failed;
56
58
page = read_cache_page(&inode->i_data, 0,
+1
include/linux/nfs_fs.h
+1
include/linux/nfs_fs.h
···
308
308
extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
309
309
extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
310
310
extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
311
+
extern int nfs_revalidate_mapping_nolock(struct inode *inode, struct address_space *mapping);
311
312
extern int nfs_setattr(struct dentry *, struct iattr *);
312
313
extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);
313
314
extern void nfs_begin_attr_update(struct inode *);