[PATCH 5.10 246/290] NFS: Dont revalidate the directory permissions on a lookup failure
From: gregkh@linuxfoundation.org
Date: 2021-03-15 14:43:57
Also in:
lkml
Subsystem:
filesystems (vfs and infrastructure), nfs, sunrpc, and lockd clients, the rest · Maintainers:
Alexander Viro, Christian Brauner, Trond Myklebust, Anna Schumaker, Linus Torvalds
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
From: Trond Myklebust <redacted>
[ Upstream commit 82e7ca1334ab16e2e04fafded1cab9dfcdc11b40 ]
There should be no reason to expect the directory permissions to change
just because the directory contents changed or a negative lookup timed
out. So let's avoid doing a full call to nfs_mark_for_revalidate() in
that case.
Furthermore, if this is a negative dentry, and we haven't actually done
a new lookup, then we have no reason yet to believe the directory has
changed at all. So let's remove the gratuitous directory inode
invalidation altogether when called from
nfs_lookup_revalidate_negative().
Reported-by: Geert Jansen <redacted>
Fixes: 5ceb9d7fdaaf ("NFS: Refactor nfs_lookup_revalidate()")
Signed-off-by: Trond Myklebust <redacted>
Signed-off-by: Anna Schumaker <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/nfs/dir.c | 20 +++++++++++++++++---
1 file changed, 17 insertions(+), 3 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 4e011adaf967..c96ae135b80f 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c@@ -1202,6 +1202,15 @@ int nfs_lookup_verify_inode(struct inode *inode, unsigned int flags) goto out; } +static void nfs_mark_dir_for_revalidate(struct inode *inode) +{ + struct nfs_inode *nfsi = NFS_I(inode); + + spin_lock(&inode->i_lock); + nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE; + spin_unlock(&inode->i_lock); +} + /* * We judge how long we want to trust negative * dentries by looking at the parent inode mtime.
@@ -1236,7 +1245,6 @@ nfs_lookup_revalidate_done(struct inode *dir, struct dentry *dentry, __func__, dentry); return 1; case 0: - nfs_mark_for_revalidate(dir); if (inode && S_ISDIR(inode->i_mode)) { /* Purge readdir caches. */ nfs_zap_caches(inode);
@@ -1326,6 +1334,13 @@ nfs_lookup_revalidate_dentry(struct inode *dir, struct dentry *dentry, nfs_free_fattr(fattr); nfs_free_fhandle(fhandle); nfs4_label_free(label); + + /* + * If the lookup failed despite the dentry change attribute being + * a match, then we should revalidate the directory cache. + */ + if (!ret && nfs_verify_change_attribute(dir, dentry->d_time)) + nfs_mark_dir_for_revalidate(dir); return nfs_lookup_revalidate_done(dir, dentry, inode, ret); }
@@ -1368,7 +1383,7 @@ nfs_do_lookup_revalidate(struct inode *dir, struct dentry *dentry, error = nfs_lookup_verify_inode(inode, flags); if (error) { if (error == -ESTALE) - nfs_zap_caches(dir); + nfs_mark_dir_for_revalidate(dir); goto out_bad; } nfs_advise_use_readdirplus(dir);
@@ -1865,7 +1880,6 @@ nfs_add_or_obtain(struct dentry *dentry, struct nfs_fh *fhandle, dput(parent); return d; out_error: - nfs_mark_for_revalidate(dir); d = ERR_PTR(error); goto out; }
--
2.30.1