[PATCH v2 15/19] nfs: don't d_drop() before d_splice_alias()

NeilBrown
2026-04-27T03:38:02Z

nfs_add_or_obtain() is used, often via nfs_instantiate(), to attach a
newly created inode to the appropriate dentry - or to provide an
alternate dentry.
It has to drop the dentry first, which is problematic for proposed
locking changes.

As d_splice_alias() now works with hashed dentries, the d_drop() is no
longer needed.

However we still d_drop() on error as the status of the name is
uncertain.

nfs_open_and_get_state() is only used for files so we should be able to
use d_instantiate(). However as that depends on the server for
correctness, it is safer to stay with the current code pattern and use
d_splice_alias() there too.

Signed-off-by: NeilBrown <neil@brown.name>
---
fs/nfs/dir.c | 3 +--
fs/nfs/nfs4proc.c | 1 -
2 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 2c1315a02e52..e1d56400fc6a 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -2329,8 +2329,6 @@ nfs_add_or_obtain(struct dentry *dentry, struct nfs_fh *fhandle,
struct dentry *d;
int error;

- d_drop(dentry);
-
if (fhandle->size == 0) {
error = NFS_PROTO(dir)->lookup(dir, dentry, &dentry->d_name,
fhandle, fattr);
@@ -2351,6 +2349,7 @@ nfs_add_or_obtain(struct dentry *dentry, struct nfs_fh *fhandle,
dput(parent);
return d;
out_error:
+ d_drop(dentry);
d = ERR_PTR(error);
goto out;
}
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index a9b8d482d289..185c933fb54c 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3099,7 +3099,6 @@ static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata,
nfs_set_verifier(dentry, dir_verifier);
if (d_really_is_negative(dentry)) {
struct dentry *alias;
- d_drop(dentry);
alias = d_splice_alias(igrab(state->inode), dentry);
/* d_splice_alias() can't fail here - it's a non-directory */
if (alias) {
--
2.50.0.107.gf914562f5916.dirty