ocfs2: handle async EAGAIN from NOQUEUE request

When using fsdlm, -EAGAIN is returned in the async callback for NOQUEUE
requests. Fix up dlmglue to expect this.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 23 insertions, 4 deletions

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 295c47f7aba2..b640423b936a 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -880,13 +880,20 @@ static void ocfs2_locking_ast(void *opaque)
         struct ocfs2_lock_res *lockres = opaque;
         struct ocfs2_super *osb = ocfs2_get_lockres_osb(lockres);
         unsigned long flags;
+        int status;
 
         spin_lock_irqsave(&lockres->l_lock, flags);
 
-        if (ocfs2_dlm_lock_status(&lockres->l_lksb)) {
+        status = ocfs2_dlm_lock_status(&lockres->l_lksb);
+
+        if (status == -EAGAIN) {
+                lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
+                goto out;
+        }
+
+        if (status) {
                 mlog(ML_ERROR, "lockres %s: lksb status value of %d!\n",
-                     lockres->l_name,
-                     ocfs2_dlm_lock_status(&lockres->l_lksb));
+                     lockres->l_name, status);
                 spin_unlock_irqrestore(&lockres->l_lock, flags);
                 return;
         }
@@ -909,7 +916,7 @@ static void ocfs2_locking_ast(void *opaque)
                      lockres->l_unlock_action);
                 BUG();
         }
-
+out:
         /* set it to something invalid so if we get called again we
          * can catch it. */
         lockres->l_action = OCFS2_AST_INVALID;
@@ -1113,6 +1120,7 @@ static int ocfs2_cluster_lock(struct ocfs2_super *osb,
         int ret = 0; /* gcc doesn't realize wait = 1 guarantees ret is set */
         unsigned long flags;
         unsigned int gen;
+        int noqueue_attempted = 0;
 
         mlog_entry_void();
 
@@ -1157,6 +1165,13 @@ again:
         }
 
         if (level > lockres->l_level) {
+                if (noqueue_attempted > 0) {
+                        ret = -EAGAIN;
+                        goto unlock;
+                }
+                if (lkm_flags & DLM_LKF_NOQUEUE)
+                        noqueue_attempted = 1;
+
                 if (lockres->l_action != OCFS2_AST_INVALID)
                         mlog(ML_ERROR, "lockres %s has action %u pending\n",
                              lockres->l_name, lockres->l_action);
@@ -1621,6 +1636,10 @@ int ocfs2_file_lock(struct file *file, int ex, int trylock)
                  * to just bubble sucess back up to the user.
                  */
                 ret = ocfs2_flock_handle_signal(lockres, level);
+        } else if (!ret && (level > lockres->l_level)) {
+                /* Trylock failed asynchronously */
+                BUG_ON(!trylock);
+                ret = -EAGAIN;
         }
 
 out: