Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm

* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm: sysfs revert add empty release function to avoid debug warning
  dm mpath: fix stall when requeueing io
  dm raid1: fix null pointer dereference in suspend
  dm raid1: fail writes if errors are not handled and log fails
  dm log: userspace fix overhead_size calcuations
  dm snapshot: persistent annotate work_queue as on stack
  dm stripe: avoid divide by zero with invalid stripe count

drivers/md/dm-log-userspace-transfer.c

@@ -172,11 +172,15 @@ int dm_consult_userspace(const char *uuid, uint64_t luid, int request_type,
 {
 	int r = 0;
 	size_t dummy = 0;
-	int overhead_size =
-		sizeof(struct dm_ulog_request *) + sizeof(struct cn_msg);
+	int overhead_size = sizeof(struct dm_ulog_request) + sizeof(struct cn_msg);
 	struct dm_ulog_request *tfr = prealloced_ulog_tfr;
 	struct receiving_pkg pkg;
 
+	/*
+	 * Given the space needed to hold the 'struct cn_msg' and
+	 * 'struct dm_ulog_request' - do we have enough payload
+	 * space remaining?
+	 */
 	if (data_size > (DM_ULOG_PREALLOCED_SIZE - overhead_size)) {
 		DMINFO("Size of tfr exceeds preallocated size");
 		return -EINVAL;
@@ -191,7 +195,7 @@ int dm_consult_userspace(const char *uuid, uint64_t luid, int request_type,
 	 */
 	mutex_lock(&dm_ulog_lock);
 
-	memset(tfr, 0, DM_ULOG_PREALLOCED_SIZE - overhead_size);
+	memset(tfr, 0, DM_ULOG_PREALLOCED_SIZE - sizeof(struct cn_msg));
 	memcpy(tfr->uuid, uuid, DM_UUID_LEN);
 	tfr->luid = luid;
 	tfr->seq = dm_ulog_seq++;

drivers/md/dm-raid1.c

@@ -724,7 +724,7 @@ static void do_writes(struct mirror_set *ms, struct bio_list *writes)
 	/*
 	 * Dispatch io.
 	 */
-	if (unlikely(ms->log_failure)) {
+	if (unlikely(ms->log_failure) && errors_handled(ms)) {
 		spin_lock_irq(&ms->lock);
 		bio_list_merge(&ms->failures, &sync);
 		spin_unlock_irq(&ms->lock);

drivers/md/dm-region-hash.c

@@ -660,10 +660,9 @@ void dm_rh_recovery_end(struct dm_region *reg, int success)
 	spin_lock_irq(&rh->region_lock);
 	if (success)
 		list_add(&reg->list, &reg->rh->recovered_regions);
-	else {
-		reg->state = DM_RH_NOSYNC;
+	else
 		list_add(&reg->list, &reg->rh->failed_recovered_regions);
-	}
+
 	spin_unlock_irq(&rh->region_lock);
 
 	rh->wakeup_workers(rh->context);

drivers/md/dm-snap-persistent.c

@@ -254,7 +254,7 @@ static int chunk_io(struct pstore *ps, void *area, chunk_t chunk, int rw,
 	 * Issue the synchronous I/O from a different thread
 	 * to avoid generic_make_request recursion.
 	 */
-	INIT_WORK(&req.work, do_metadata);
+	INIT_WORK_ON_STACK(&req.work, do_metadata);
 	queue_work(ps->metadata_wq, &req.work);
 	flush_workqueue(ps->metadata_wq);
 

drivers/md/dm-stripe.c

@@ -110,7 +110,7 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	}
 
 	stripes = simple_strtoul(argv[0], &end, 10);
-	if (*end) {
+	if (!stripes || *end) {
 		ti->error = "Invalid stripe count";
 		return -EINVAL;
 	}

drivers/md/dm-sysfs.c

@@ -79,13 +79,6 @@ static struct sysfs_ops dm_sysfs_ops = {
 	.show	= dm_attr_show,
 };
 
-/*
- * The sysfs structure is embedded in md struct, nothing to do here
- */
-static void dm_sysfs_release(struct kobject *kobj)
-{
-}
-
 /*
  * dm kobject is embedded in mapped_device structure
  * no need to define release function here
@@ -93,7 +86,6 @@ static void dm_sysfs_release(struct kobject *kobj)
 static struct kobj_type dm_ktype = {
 	.sysfs_ops	= &dm_sysfs_ops,
 	.default_attrs	= dm_attrs,
-	.release	= dm_sysfs_release
 };
 
 /*

drivers/md/dm.c

@@ -1595,10 +1595,15 @@ static int dm_prep_fn(struct request_queue *q, struct request *rq)
 	return BLKPREP_OK;
 }
 
-static void map_request(struct dm_target *ti, struct request *clone,
+/*
+ * Returns:
+ * 0  : the request has been processed (not requeued)
+ * !0 : the request has been requeued
+ */
+static int map_request(struct dm_target *ti, struct request *clone,
 		       struct mapped_device *md)
 {
-	int r;
+	int r, requeued = 0;
 	struct dm_rq_target_io *tio = clone->end_io_data;
 
 	/*
@@ -1625,6 +1630,7 @@ static void map_request(struct dm_target *ti, struct request *clone,
 	case DM_MAPIO_REQUEUE:
 		/* The target wants to requeue the I/O */
 		dm_requeue_unmapped_request(clone);
+		requeued = 1;
 		break;
 	default:
 		if (r > 0) {
@@ -1636,6 +1642,8 @@ static void map_request(struct dm_target *ti, struct request *clone,
 		dm_kill_unmapped_request(clone, r);
 		break;
 	}
+
+	return requeued;
 }
 
 /*
@@ -1677,12 +1685,17 @@ static void dm_request_fn(struct request_queue *q)
 		atomic_inc(&md->pending[rq_data_dir(clone)]);
 
 		spin_unlock(q->queue_lock);
-		map_request(ti, clone, md);
+		if (map_request(ti, clone, md))
+			goto requeued;
+
 		spin_lock_irq(q->queue_lock);
 	}
 
 	goto out;
 
+requeued:
+	spin_lock_irq(q->queue_lock);
+
 plug_and_out:
 	if (!elv_queue_empty(q))
 		/* Some requests still remain, retry later */