From: Jeff Layton <jlayton@kernel.org>
Date: Thu, 5 Jan 2023 12:15:12 +0000 (-0500)
Subject: nfsd: add some comments to nfsd_file_do_acquire
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=b5a439e8b087963bf860bbe3b092c196c6eccf16;p=users%2Fdwmw2%2Flinux.git

nfsd: add some comments to nfsd_file_do_acquire

[ Upstream commit b680cb9b737331aad271feebbedafb865504e234 ]

David Howells mentioned that he found this bit of code confusing, so
sprinkle in some comments to clarify.

Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---

diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index 43bb2fd47cf58..faa0c7d0253eb 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -1093,6 +1093,11 @@ retry:
 	rcu_read_unlock();
 
 	if (nf) {
+		/*
+		 * If the nf is on the LRU then it holds an extra reference
+		 * that must be put if it's removed. It had better not be
+		 * the last one however, since we should hold another.
+		 */
 		if (nfsd_file_lru_remove(nf))
 			WARN_ON_ONCE(refcount_dec_and_test(&nf->nf_ref));
 		goto wait_for_construction;