ocfs2: handle async EAGAIN from NOQUEUE request

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / ocfs2 / dlmglue.c

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 295c47f7aba2829d3289e8e8d0f5135b24e54998..b640423b936ab46668276b483da8e4bd54942c53 100644 (file)
--- 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: