releases/4.19.2/nfs-fix-a-missed-page-unlock-after-pg_doio.patch

   1 From fdbd1a2e4a71adcb1ae219fcfd964930d77a7f84 Mon Sep 17 00:00:00 2001
   2 From: Benjamin Coddington <bcodding@redhat.com>
   3 Date: Thu, 18 Oct 2018 15:01:48 -0400
   4 Subject: nfs: Fix a missed page unlock after pg_doio()
   5
   6 From: Benjamin Coddington <bcodding@redhat.com>
   7
   8 commit fdbd1a2e4a71adcb1ae219fcfd964930d77a7f84 upstream.
   9
  10 We must check pg_error and call error_cleanup after any call to pg_doio.
  11 Currently, we are skipping the unlock of a page if we encounter an error in
  12 nfs_pageio_complete() before handing off the work to the RPC layer.
  13
  14 Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
  15 Cc: stable@vger.kernel.org
  16 Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
  17 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  18
  19 ---
  20  fs/nfs/pagelist.c |   40 +++++++++++++++++++++-------------------
  21  1 file changed, 21 insertions(+), 19 deletions(-)
  22
  23 --- a/fs/nfs/pagelist.c
  24 +++ b/fs/nfs/pagelist.c
  25 @@ -1111,6 +1111,20 @@ static int nfs_pageio_add_request_mirror
  26         return ret;
  27  }
  28
  29 +static void nfs_pageio_error_cleanup(struct nfs_pageio_descriptor *desc)
  30 +{
  31 +       u32 midx;
  32 +       struct nfs_pgio_mirror *mirror;
  33 +
  34 +       if (!desc->pg_error)
  35 +               return;
  36 +
  37 +       for (midx = 0; midx < desc->pg_mirror_count; midx++) {
  38 +               mirror = &desc->pg_mirrors[midx];
  39 +               desc->pg_completion_ops->error_cleanup(&mirror->pg_list);
  40 +       }
  41 +}
  42 +
  43  int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc,
  44                            struct nfs_page *req)
  45  {
  46 @@ -1161,25 +1175,11 @@ int nfs_pageio_add_request(struct nfs_pa
  47         return 1;
  48
  49  out_failed:
  50 -       /*
  51 -        * We might have failed before sending any reqs over wire.
  52 -        * Clean up rest of the reqs in mirror pg_list.
  53 -        */
  54 -       if (desc->pg_error) {
  55 -               struct nfs_pgio_mirror *mirror;
  56 -               void (*func)(struct list_head *);
  57 -
  58 -               /* remember fatal errors */
  59 -               if (nfs_error_is_fatal(desc->pg_error))
  60 -                       nfs_context_set_write_error(req->wb_context,
  61 -                                                   desc->pg_error);
  62 -
  63 -               func = desc->pg_completion_ops->error_cleanup;
  64 -               for (midx = 0; midx < desc->pg_mirror_count; midx++) {
  65 -                       mirror = &desc->pg_mirrors[midx];
  66 -                       func(&mirror->pg_list);
  67 -               }
  68 -       }
  69 +       /* remember fatal errors */
  70 +       if (nfs_error_is_fatal(desc->pg_error))
  71 +               nfs_context_set_write_error(req->wb_context,
  72 +                                               desc->pg_error);
  73 +       nfs_pageio_error_cleanup(desc);
  74         return 0;
  75  }
  76
  77 @@ -1251,6 +1251,8 @@ void nfs_pageio_complete(struct nfs_page
  78         for (midx = 0; midx < desc->pg_mirror_count; midx++)
  79                 nfs_pageio_complete_mirror(desc, midx);
  80
  81 +       if (desc->pg_error < 0)
  82 +               nfs_pageio_error_cleanup(desc);
  83         if (desc->pg_ops->pg_cleanup)
  84                 desc->pg_ops->pg_cleanup(desc);
  85         nfs_pageio_cleanup_mirroring(desc);