queue-4.14/9p-locks-add-mount-option-for-lock-retry-interval.patch

   1 From 9eb0f818d6a3eb7d236730aa441591d79b4a9c3a Mon Sep 17 00:00:00 2001
   2 From: Dinu-Razvan Chis-Serban <justcsdr@gmail.com>
   3 Date: Wed, 5 Sep 2018 16:44:12 +0900
   4 Subject: 9p locks: add mount option for lock retry interval
   5
   6 [ Upstream commit 5e172f75e51e3de1b4274146d9b990f803cb5c2a ]
   7
   8 The default P9_LOCK_TIMEOUT can be too long for some users exporting
   9 a local file system to a guest VM (30s), make this configurable at
  10 mount time.
  11
  12 Link: http://lkml.kernel.org/r/1536295827-3181-1-git-send-email-asmadeus@codewreck.org
  13 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195727
  14 Signed-off-by: Dinu-Razvan Chis-Serban <justcsdr@gmail.com>
  15 Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
  16 Signed-off-by: Sasha Levin <sashal@kernel.org>
  17 ---
  18  fs/9p/v9fs.c     | 21 +++++++++++++++++++++
  19  fs/9p/v9fs.h     |  1 +
  20  fs/9p/vfs_file.c |  6 +++++-
  21  3 files changed, 27 insertions(+), 1 deletion(-)
  22
  23 diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
  24 index 8fb89ddc6cc7..c52f10efdc9c 100644
  25 --- a/fs/9p/v9fs.c
  26 +++ b/fs/9p/v9fs.c
  27 @@ -61,6 +61,8 @@ enum {
  28         Opt_cache_loose, Opt_fscache, Opt_mmap,
  29         /* Access options */
  30         Opt_access, Opt_posixacl,
  31 +       /* Lock timeout option */
  32 +       Opt_locktimeout,
  33         /* Error token */
  34         Opt_err
  35  };
  36 @@ -80,6 +82,7 @@ static const match_table_t tokens = {
  37         {Opt_cachetag, "cachetag=%s"},
  38         {Opt_access, "access=%s"},
  39         {Opt_posixacl, "posixacl"},
  40 +       {Opt_locktimeout, "locktimeout=%u"},
  41         {Opt_err, NULL}
  42  };
  43
  44 @@ -187,6 +190,7 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
  45  #ifdef CONFIG_9P_FSCACHE
  46         v9ses->cachetag = NULL;
  47  #endif
  48 +       v9ses->session_lock_timeout = P9_LOCK_TIMEOUT;
  49
  50         if (!opts)
  51                 return 0;
  52 @@ -360,6 +364,23 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
  53  #endif
  54                         break;
  55
  56 +               case Opt_locktimeout:
  57 +                       r = match_int(&args[0], &option);
  58 +                       if (r < 0) {
  59 +                               p9_debug(P9_DEBUG_ERROR,
  60 +                                        "integer field, but no integer?\n");
  61 +                               ret = r;
  62 +                               continue;
  63 +                       }
  64 +                       if (option < 1) {
  65 +                               p9_debug(P9_DEBUG_ERROR,
  66 +                                        "locktimeout must be a greater than zero integer.\n");
  67 +                               ret = -EINVAL;
  68 +                               continue;
  69 +                       }
  70 +                       v9ses->session_lock_timeout = (long)option * HZ;
  71 +                       break;
  72 +
  73                 default:
  74                         continue;
  75                 }
  76 diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
  77 index 982e017acadb..129e5243a6bf 100644
  78 --- a/fs/9p/v9fs.h
  79 +++ b/fs/9p/v9fs.h
  80 @@ -116,6 +116,7 @@ struct v9fs_session_info {
  81         struct p9_client *clnt; /* 9p client */
  82         struct list_head slist; /* list of sessions registered with v9fs */
  83         struct rw_semaphore rename_sem;
  84 +       long session_lock_timeout; /* retry interval for blocking locks */
  85  };
  86
  87  /* cache_validity flags */
  88 diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
  89 index af8cac975a74..89e69904976a 100644
  90 --- a/fs/9p/vfs_file.c
  91 +++ b/fs/9p/vfs_file.c
  92 @@ -154,6 +154,7 @@ static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
  93         uint8_t status = P9_LOCK_ERROR;
  94         int res = 0;
  95         unsigned char fl_type;
  96 +       struct v9fs_session_info *v9ses;
  97
  98         fid = filp->private_data;
  99         BUG_ON(fid == NULL);
 100 @@ -189,6 +190,8 @@ static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
 101         if (IS_SETLKW(cmd))
 102                 flock.flags = P9_LOCK_FLAGS_BLOCK;
 103
 104 +       v9ses = v9fs_inode2v9ses(file_inode(filp));
 105 +
 106         /*
 107          * if its a blocked request and we get P9_LOCK_BLOCKED as the status
 108          * for lock request, keep on trying
 109 @@ -202,7 +205,8 @@ static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
 110                         break;
 111                 if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
 112                         break;
 113 -               if (schedule_timeout_interruptible(P9_LOCK_TIMEOUT) != 0)
 114 +               if (schedule_timeout_interruptible(v9ses->session_lock_timeout)
 115 +                               != 0)
 116                         break;
 117                 /*
 118                  * p9_client_lock_dotl overwrites flock.client_id with the
 119 --
 120 2.19.1
 121