5.10-stable review patch. If anyone has any objections, please let me know.
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From: Chuck Lever chuck.lever@oracle.com
[ Upstream commit 68c522afd0b1936b48a03a4c8b81261e7597c62d ]
nfsd_rename() can kick off a CB_RECALL (via vfs_rename() -> leases_conflict()) if a delegation is present. Before returning NFS4ERR_DELAY, give the client holding that delegation a chance to return it and then retry the nfsd_rename() again, once.
This version of the patch handles renaming an existing file, but does not deal with renaming onto an existing file. That case will still always trigger an NFS4ERR_DELAY.
Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=354 Tested-by: Igor Mammedov imammedo@redhat.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/vfs.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index dc79db261d6a2..5684845d95119 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1711,7 +1711,15 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, .new_dir = tdir, .new_dentry = ndentry, }; - host_err = vfs_rename(&rd); + int retries; + + for (retries = 1;;) { + host_err = vfs_rename(&rd); + if (host_err != -EAGAIN || !retries--) + break; + if (!nfsd_wait_for_delegreturn(rqstp, d_inode(odentry))) + break; + } if (!host_err) { host_err = commit_metadata(tfhp); if (!host_err)