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| author | J. Bruce Fields <bfields@redhat.com> | 2013-10-15 17:03:16 -0400 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2013-10-28 19:19:19 -0400 |
| commit | a3f432bfd06a4ec3b812e32d3266e0d1ad75d008 (patch) | |
| tree | 0e360753066b9dc61df85b2c5234f544ff418527 /fs/nfs/dir.c | |
| parent | 9d3a2260f0f4bd6379b0a0f131c743fff25b0029 (diff) | |
| download | linux-a3f432bfd06a4ec3b812e32d3266e0d1ad75d008.tar.gz | |
nfs: use IS_ROOT not DCACHE_DISCONNECTED
This check was added by Al Viro with d9e80b7de91db05c1c4d2e5ebbfd70b3b3ba0e0f "nfs d_revalidate() is too trigger-happy with d_drop()", with the explanation that we don't want to remove the root of a disconnected tree, which will still be included on the s_anon list. But DCACHE_DISCONNECTED does *not* actually identify dentries that are disconnected from the dentry tree or hashed on s_anon. IS_ROOT() is the way to do that. Also add a comment from Al's commit to remind us why this check is there. Signed-off-by: J. Bruce Fields <bfields@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs/dir.c')
| -rw-r--r-- | fs/nfs/dir.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 02b0df769e2d..6cc51ae0638d 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1139,7 +1139,13 @@ out_zap_parent: if (inode && S_ISDIR(inode->i_mode)) { /* Purge readdir caches. */ nfs_zap_caches(inode); - if (dentry->d_flags & DCACHE_DISCONNECTED) + /* + * We can't d_drop the root of a disconnected tree: + * its d_hash is on the s_anon list and d_drop() would hide + * it from shrink_dcache_for_unmount(), leading to busy + * inodes on unmount and further oopses. + */ + if (IS_ROOT(dentry)) goto out_valid; } /* If we have submounts, don't unhash ! */ |