We can optimise away any lookup for a rename target, unless we're
being asked to revalidate a dentry that might be in use.
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
---
fs/nfs/dir.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 9dde88334c9c..b315f53b3aec 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1051,13 +1051,15 @@ int nfs_lookup_verify_inode(struct inode *inode, unsigned int flags)
*
* If LOOKUP_RCU prevents us from performing a full check, return 1
* suggesting a reval is needed.
+ *
+ * Note that when creating a new file, or looking up a rename target,
+ * then it shouldn't be necessary to revalidate a negative dentry.
*/
static inline
int nfs_neg_need_reval(struct inode *dir, struct dentry *dentry,
unsigned int flags)
{
- /* Don't revalidate a negative dentry if we're creating a new file */
- if (flags & LOOKUP_CREATE)
+ if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
return 0;
if (NFS_SERVER(dir)->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG)
return 1;
@@ -1347,7 +1349,7 @@ struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, unsigned in
* If we're doing an exclusive create, optimize away the lookup
* but don't hash the dentry.
*/
- if (nfs_is_exclusive_create(dir, flags))
+ if (nfs_is_exclusive_create(dir, flags) || flags & LOOKUP_RENAME_TARGET)
return NULL;
res = ERR_PTR(-ENOMEM);
--
2.17.0
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
