[PATCH 2/2] NFS: Don't gratuitously clear the inode cache when lookup failed

From: trondmy@kernel.org
To: Geert Jansen <gerardu@amazon.com>
Cc: linux-nfs@vger.kernel.org
Subject: [PATCH 2/2] NFS: Don't gratuitously clear the inode cache when lookup failed
Date: Tue,  2 Mar 2021 23:28:36 -0500	[thread overview]
Message-ID: <20210303042836.200413-2-trondmy@kernel.org> (raw)
In-Reply-To: <20210303042836.200413-1-trondmy@kernel.org>

From: Trond Myklebust <trond.myklebust@hammerspace.com>

The fact that the lookup revalidation failed, does not mean that the
inode contents have changed.

Fixes: 5ceb9d7fdaaf ("NFS: Refactor nfs_lookup_revalidate()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 fs/nfs/dir.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 6350873cb8bd..deb6ad0622ed 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1444,18 +1444,14 @@ nfs_lookup_revalidate_done(struct inode *dir, struct dentry *dentry,
 			__func__, dentry);
 		return 1;
 	case 0:
-		if (inode && S_ISDIR(inode->i_mode)) {
-			/* Purge readdir caches. */
-			nfs_zap_caches(inode);
-			/*
-			 * 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))
-				return 1;
-		}
+		/*
+		 * 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 (inode && IS_ROOT(dentry))
+			return 1;
 		dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) is invalid\n",
 				__func__, dentry);
 		return 0;
-- 
2.29.2

