[RFC,22/24] nfs: skip dentry revalidation when parent dir has a delegation

Commit Message

Jeffrey Layton March 15, 2024, 4:53 p.m. UTC

If the parent has a valid delegation, then test whether the
dentry->d_time matches the current change attr on the directory. If it
does, then we can declare the dentry valid with no further checks.

Signed-off-by: Jeff Layton <[e-mail]>
---
 fs/nfs/dir.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

Patch

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index ac505671efbd..061648c73116 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -2188,6 +2188,15 @@  int nfs_atomic_open(struct inode *dir, struct dentry *dentry,
 }
 EXPORT_SYMBOL_GPL(nfs_atomic_open);
 
+static int
+nfs_lookup_revalidate_delegated_parent(struct inode *dir, struct dentry *dentry,
+				       struct inode *inode)
+{
+	return nfs_lookup_revalidate_done(dir, dentry, inode,
+					  nfs_verify_change_attribute(dir, dentry->d_time) ?
+					  1 : 0);
+}
+
 static int
 nfs4_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
 			  unsigned int flags)
@@ -2212,6 +2221,9 @@  nfs4_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
 	if (nfs_verifier_is_delegated(dentry))
 		return nfs_lookup_revalidate_delegated(dir, dentry, inode);
 
+	if (nfs_have_delegated_attributes(dir))
+		return nfs_lookup_revalidate_delegated_parent(dir, dentry, inode);
+
 	/* NFS only supports OPEN on regular files */
 	if (!S_ISREG(inode->i_mode))
 		goto full_reval;