ocfs2: give the dlm dirty list a reference on the lockres

Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h
index 78eccd0951e4ea847c4ffd9062eb8f9537b8a77e..829cc39488041d3dcc13aa26d0675e0567e6f0c6 100644 (file)
--- a/fs/ocfs2/dlm/dlmcommon.h
+++ b/fs/ocfs2/dlm/dlmcommon.h
@@ -235,18 +235,26 @@ struct dlm_lock_resource
        struct qstr lockname;
        struct kref      refs;
 
-       /* please keep these next 3 in this order
-        * some funcs want to iterate over all lists */
+       /*
+        * Please keep granted, converting, and blocked in this order,
+        * as some funcs want to iterate over all lists.
+        *
+        * All four lists are protected by the hash's reference.
+        */
        struct list_head granted;
        struct list_head converting;
        struct list_head blocked;
+       struct list_head purge;
 
+       /*
+        * These two lists require you to hold an additional reference
+        * while they are on the list.
+        */
        struct list_head dirty;
        struct list_head recovering; // dlm_recovery_ctxt.resources list
 
        /* unused lock resources have their last_used stamped and are
         * put on a list for the dlm thread to run. */
-       struct list_head purge;
        unsigned long    last_used;
 
        unsigned migration_pending:1;

diff --git a/fs/ocfs2/dlm/dlmthread.c b/fs/ocfs2/dlm/dlmthread.c
index 76526ea95bb2a58a286c4003740b95bc4eefadc7..610dc76a851b985a5364c88006cfb47b549196c5 100644 (file)
--- a/fs/ocfs2/dlm/dlmthread.c
+++ b/fs/ocfs2/dlm/dlmthread.c
@@ -455,6 +455,8 @@ void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
        /* don't shuffle secondary queues */
        if ((res->owner == dlm->node_num) &&
            !(res->state & DLM_LOCK_RES_DIRTY)) {
+               /* ref for dirty_list */
+               dlm_lockres_get(res);
                list_add_tail(&res->dirty, &dlm->dirty_list);
                res->state |= DLM_LOCK_RES_DIRTY;
        }
@@ -639,6 +641,8 @@ static int dlm_thread(void *data)
                        list_del_init(&res->dirty);
                        spin_unlock(&res->spinlock);
                        spin_unlock(&dlm->spinlock);
+                       /* Drop dirty_list ref */
+                       dlm_lockres_put(res);
 
                        /* lockres can be re-dirtied/re-added to the
                         * dirty_list in this gap, but that is ok */
@@ -691,6 +695,8 @@ in_progress:
                        /* if the lock was in-progress, stick
                         * it on the back of the list */
                        if (delay) {
+                               /* ref for dirty_list */
+                               dlm_lockres_get(res);
                                spin_lock(&res->spinlock);
                                list_add_tail(&res->dirty, &dlm->dirty_list);
                                res->state |= DLM_LOCK_RES_DIRTY;