queue-5.15/nfsd-clean-up-nfsd_file_put.patch

   1 From cbe3d42fb4d7e2683b1fbb63c228ae322ffbfa04 Mon Sep 17 00:00:00 2001
   2 From: Sasha Levin <sashal@kernel.org>
   3 Date: Thu, 31 Mar 2022 09:54:02 -0400
   4 Subject: nfsd: Clean up nfsd_file_put()
   5
   6 From: Trond Myklebust <trond.myklebust@hammerspace.com>
   7
   8 [ Upstream commit 999397926ab3f78c7d1235cc4ca6e3c89d2769bf ]
   9
  10 Make it a little less racy, by removing the refcount_read() test. Then
  11 remove the redundant 'is_hashed' variable.
  12
  13 Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
  14 Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
  15 ---
  16  fs/nfsd/filecache.c | 13 +++----------
  17  1 file changed, 3 insertions(+), 10 deletions(-)
  18
  19 diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
  20 index 6cde6ef68996e..429ae485ebbbe 100644
  21 --- a/fs/nfsd/filecache.c
  22 +++ b/fs/nfsd/filecache.c
  23 @@ -295,21 +295,14 @@ nfsd_file_put_noref(struct nfsd_file *nf)
  24  void
  25  nfsd_file_put(struct nfsd_file *nf)
  26  {
  27 -       bool is_hashed;
  28 -
  29         set_bit(NFSD_FILE_REFERENCED, &nf->nf_flags);
  30 -       if (refcount_read(&nf->nf_ref) > 2 || !nf->nf_file) {
  31 -               nfsd_file_put_noref(nf);
  32 -               return;
  33 -       }
  34 -
  35 -       is_hashed = test_bit(NFSD_FILE_HASHED, &nf->nf_flags) != 0;
  36 -       if (!is_hashed) {
  37 +       if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags) == 0) {
  38                 nfsd_file_flush(nf);
  39                 nfsd_file_put_noref(nf);
  40         } else {
  41                 nfsd_file_put_noref(nf);
  42 -               nfsd_file_schedule_laundrette();
  43 +               if (nf->nf_file)
  44 +                       nfsd_file_schedule_laundrette();
  45         }
  46         if (atomic_long_read(&nfsd_filecache_count) >= NFSD_FILE_LRU_LIMIT)
  47                 nfsd_file_gc();
  48 --
  49 2.43.0
  50