[PATCH 5.5 191/367] nfsd: fix filecache lookup

Greg Kroah-Hartman
2020-02-10T12:49:46Z

From: Trond Myklebust <trondmy@gmail.com>

commit 28c7d86bb6172ffbb1a1237c6388e77f9fe5f181 upstream.

If the lookup keeps finding a nfsd_file with an unhashed open file,
then retry once only.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org
Fixes: 65294c1f2c5e "nfsd: add a new struct file caching facility to nfsd"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/nfsd/filecache.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -789,6 +789,7 @@ nfsd_file_acquire(struct svc_rqst *rqstp
struct nfsd_file *nf, *new;
struct inode *inode;
unsigned int hashval;
+ bool retry = true;

/* FIXME: skip this if fh_dentry is already set? */
status = fh_verify(rqstp, fhp, S_IFREG,
@@ -824,6 +825,11 @@ wait_for_construction:

/* Did construction of this file fail? */
if (!test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
+ if (!retry) {
+ status = nfserr_jukebox;
+ goto out;
+ }
+ retry = false;
nfsd_file_put_noref(nf);
goto retry;
}