ocfs2: Change the recovery map to an array of node numbers.
The old recovery map was a bitmap of node numbers. This was sufficient
for the maximum node number of 254. Going forward, we want node numbers
to be UINT32. Thus, we need a new recovery map.
Note that we can't keep track of slots here. We must write down the
node number to recovery *before* we get the locks needed to convert a
node number into a slot number.
The recovery map is now an array of unsigned ints, max_slots in size.
It moves to journal.c with the rest of recovery.
Because it needs to be initialized, we move all of recovery initialization
into a new function, ocfs2_recovery_init(). This actually cleans up
ocfs2_initialize_super() a little as well. Following on, recovery cleaup
becomes part of ocfs2_recovery_exit().
A number of node map functions are rendered obsolete and are removed.
Finally, waiting on recovery is wrapped in a function rather than naked
checks on the recovery_event. This is a cleanup from Mark.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index ed0c6d0..ca4c0ea 100644
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -64,6 +64,137 @@
int slot);
static int ocfs2_commit_thread(void *arg);
+
+/*
+ * The recovery_list is a simple linked list of node numbers to recover.
+ * It is protected by the recovery_lock.
+ */
+
+struct ocfs2_recovery_map {
+ int rm_used;
+ unsigned int *rm_entries;
+};
+
+int ocfs2_recovery_init(struct ocfs2_super *osb)
+{
+ struct ocfs2_recovery_map *rm;
+
+ mutex_init(&osb->recovery_lock);
+ osb->disable_recovery = 0;
+ osb->recovery_thread_task = NULL;
+ init_waitqueue_head(&osb->recovery_event);
+
+ rm = kzalloc(sizeof(struct ocfs2_recovery_map) +
+ osb->max_slots * sizeof(unsigned int),
+ GFP_KERNEL);
+ if (!rm) {
+ mlog_errno(-ENOMEM);
+ return -ENOMEM;
+ }
+
+ rm->rm_entries = (unsigned int *)((char *)rm +
+ sizeof(struct ocfs2_recovery_map));
+ osb->recovery_map = rm;
+
+ return 0;
+}
+
+/* we can't grab the goofy sem lock from inside wait_event, so we use
+ * memory barriers to make sure that we'll see the null task before
+ * being woken up */
+static int ocfs2_recovery_thread_running(struct ocfs2_super *osb)
+{
+ mb();
+ return osb->recovery_thread_task != NULL;
+}
+
+void ocfs2_recovery_exit(struct ocfs2_super *osb)
+{
+ struct ocfs2_recovery_map *rm;
+
+ /* disable any new recovery threads and wait for any currently
+ * running ones to exit. Do this before setting the vol_state. */
+ mutex_lock(&osb->recovery_lock);
+ osb->disable_recovery = 1;
+ mutex_unlock(&osb->recovery_lock);
+ wait_event(osb->recovery_event, !ocfs2_recovery_thread_running(osb));
+
+ /* At this point, we know that no more recovery threads can be
+ * launched, so wait for any recovery completion work to
+ * complete. */
+ flush_workqueue(ocfs2_wq);
+
+ /*
+ * Now that recovery is shut down, and the osb is about to be
+ * freed, the osb_lock is not taken here.
+ */
+ rm = osb->recovery_map;
+ /* XXX: Should we bug if there are dirty entries? */
+
+ kfree(rm);
+}
+
+static int __ocfs2_recovery_map_test(struct ocfs2_super *osb,
+ unsigned int node_num)
+{
+ int i;
+ struct ocfs2_recovery_map *rm = osb->recovery_map;
+
+ assert_spin_locked(&osb->osb_lock);
+
+ for (i = 0; i < rm->rm_used; i++) {
+ if (rm->rm_entries[i] == node_num)
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Behaves like test-and-set. Returns the previous value */
+static int ocfs2_recovery_map_set(struct ocfs2_super *osb,
+ unsigned int node_num)
+{
+ struct ocfs2_recovery_map *rm = osb->recovery_map;
+
+ spin_lock(&osb->osb_lock);
+ if (__ocfs2_recovery_map_test(osb, node_num)) {
+ spin_unlock(&osb->osb_lock);
+ return 1;
+ }
+
+ /* XXX: Can this be exploited? Not from o2dlm... */
+ BUG_ON(rm->rm_used >= osb->max_slots);
+
+ rm->rm_entries[rm->rm_used] = node_num;
+ rm->rm_used++;
+ spin_unlock(&osb->osb_lock);
+
+ return 0;
+}
+
+static void ocfs2_recovery_map_clear(struct ocfs2_super *osb,
+ unsigned int node_num)
+{
+ int i;
+ struct ocfs2_recovery_map *rm = osb->recovery_map;
+
+ spin_lock(&osb->osb_lock);
+
+ for (i = 0; i < rm->rm_used; i++) {
+ if (rm->rm_entries[i] == node_num)
+ break;
+ }
+
+ if (i < rm->rm_used) {
+ /* XXX: be careful with the pointer math */
+ memmove(&(rm->rm_entries[i]), &(rm->rm_entries[i + 1]),
+ (rm->rm_used - i - 1) * sizeof(unsigned int));
+ rm->rm_used--;
+ }
+
+ spin_unlock(&osb->osb_lock);
+}
+
static int ocfs2_commit_cache(struct ocfs2_super *osb)
{
int status = 0;
@@ -650,6 +781,23 @@
return status;
}
+static int ocfs2_recovery_completed(struct ocfs2_super *osb)
+{
+ int empty;
+ struct ocfs2_recovery_map *rm = osb->recovery_map;
+
+ spin_lock(&osb->osb_lock);
+ empty = (rm->rm_used == 0);
+ spin_unlock(&osb->osb_lock);
+
+ return empty;
+}
+
+void ocfs2_wait_for_recovery(struct ocfs2_super *osb)
+{
+ wait_event(osb->recovery_event, ocfs2_recovery_completed(osb));
+}
+
/*
* JBD Might read a cached version of another nodes journal file. We
* don't want this as this file changes often and we get no
@@ -848,6 +996,7 @@
{
int status, node_num;
struct ocfs2_super *osb = arg;
+ struct ocfs2_recovery_map *rm = osb->recovery_map;
mlog_entry_void();
@@ -863,26 +1012,29 @@
goto bail;
}
- while(!ocfs2_node_map_is_empty(osb, &osb->recovery_map)) {
- node_num = ocfs2_node_map_first_set_bit(osb,
- &osb->recovery_map);
- if (node_num == O2NM_INVALID_NODE_NUM) {
- mlog(0, "Out of nodes to recover.\n");
- break;
- }
+ spin_lock(&osb->osb_lock);
+ while (rm->rm_used) {
+ /* It's always safe to remove entry zero, as we won't
+ * clear it until ocfs2_recover_node() has succeeded. */
+ node_num = rm->rm_entries[0];
+ spin_unlock(&osb->osb_lock);
status = ocfs2_recover_node(osb, node_num);
- if (status < 0) {
+ if (!status) {
+ ocfs2_recovery_map_clear(osb, node_num);
+ } else {
mlog(ML_ERROR,
"Error %d recovering node %d on device (%u,%u)!\n",
status, node_num,
MAJOR(osb->sb->s_dev), MINOR(osb->sb->s_dev));
mlog(ML_ERROR, "Volume requires unmount.\n");
- continue;
}
- ocfs2_recovery_map_clear(osb, node_num);
+ spin_lock(&osb->osb_lock);
}
+ spin_unlock(&osb->osb_lock);
+ mlog(0, "All nodes recovered\n");
+
ocfs2_super_unlock(osb, 1);
/* We always run recovery on our own orphan dir - the dead
@@ -893,8 +1045,7 @@
bail:
mutex_lock(&osb->recovery_lock);
- if (!status &&
- !ocfs2_node_map_is_empty(osb, &osb->recovery_map)) {
+ if (!status && !ocfs2_recovery_completed(osb)) {
mutex_unlock(&osb->recovery_lock);
goto restart;
}
@@ -924,8 +1075,8 @@
/* People waiting on recovery will wait on
* the recovery map to empty. */
- if (!ocfs2_recovery_map_set(osb, node_num))
- mlog(0, "node %d already be in recovery.\n", node_num);
+ if (ocfs2_recovery_map_set(osb, node_num))
+ mlog(0, "node %d already in recovery map.\n", node_num);
mlog(0, "starting recovery thread...\n");
@@ -1197,7 +1348,7 @@
if (status == -ENOENT)
continue;
- if (ocfs2_node_map_test_bit(osb, &osb->recovery_map, node_num))
+ if (__ocfs2_recovery_map_test(osb, node_num))
continue;
spin_unlock(&osb->osb_lock);