Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cfq-iosched: Do not idle on async queues
  blk-cgroup: Fix potential deadlock in blk-cgroup
  block: fix bugs in bio-integrity mempool usage
  block: fix bio_add_page for non trivial merge_bvec_fn case
  drbd: null dereference bug
  drbd: fix max_segment_size initialization

block/blk-cgroup.c

@@ -147,16 +147,16 @@ blkiocg_weight_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
 		return -EINVAL;
 
 	blkcg = cgroup_to_blkio_cgroup(cgroup);
+	spin_lock(&blkio_list_lock);
 	spin_lock_irq(&blkcg->lock);
 	blkcg->weight = (unsigned int)val;
 	hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) {
-		spin_lock(&blkio_list_lock);
 		list_for_each_entry(blkiop, &blkio_list, list)
 			blkiop->ops.blkio_update_group_weight_fn(blkg,
 					blkcg->weight);
-		spin_unlock(&blkio_list_lock);
 	}
 	spin_unlock_irq(&blkcg->lock);
+	spin_unlock(&blkio_list_lock);
 	return 0;
 }
 

block/cfq-iosched.c

@@ -1803,7 +1803,7 @@ static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq)
 	 * Otherwise, we do only if they are the last ones
 	 * in their service tree.
 	 */
-	return service_tree->count == 1;
+	return service_tree->count == 1 && cfq_cfqq_sync(cfqq);
 }
 
 static void cfq_arm_slice_timer(struct cfq_data *cfqd)

drivers/block/drbd/drbd_main.c

@@ -2973,7 +2973,6 @@ struct drbd_conf *drbd_new_device(unsigned int minor)
 		goto out_no_q;
 	mdev->rq_queue = q;
 	q->queuedata   = mdev;
-	blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE);
 
 	disk = alloc_disk(1);
 	if (!disk)
@@ -2997,6 +2996,7 @@ struct drbd_conf *drbd_new_device(unsigned int minor)
 	q->backing_dev_info.congested_data = mdev;
 
 	blk_queue_make_request(q, drbd_make_request_26);
+	blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE);
 	blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
 	blk_queue_merge_bvec(q, drbd_merge_bvec);
 	q->queue_lock = &mdev->req_lock; /* needed since we use */

drivers/block/drbd/drbd_receiver.c

@@ -1224,7 +1224,7 @@ static int receive_Barrier(struct drbd_conf *mdev, struct p_header *h)
 	epoch = kmalloc(sizeof(struct drbd_epoch), GFP_NOIO);
 	if (!epoch) {
 		dev_warn(DEV, "Allocation of an epoch failed, slowing down\n");
-		issue_flush = !test_and_set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &epoch->flags);
+		issue_flush = !test_and_set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &mdev->current_epoch->flags);
 		drbd_wait_ee_list_empty(mdev, &mdev->active_ee);
 		if (issue_flush) {
 			rv = drbd_flush_after_epoch(mdev, mdev->current_epoch);

fs/bio-integrity.c

@@ -61,7 +61,7 @@ static inline unsigned int vecs_to_idx(unsigned int nr)
 
 static inline int use_bip_pool(unsigned int idx)
 {
-	if (idx == BIOVEC_NR_POOLS)
+	if (idx == BIOVEC_MAX_IDX)
 		return 1;
 
 	return 0;
@@ -95,6 +95,7 @@ struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *bio,
 
 	/* Use mempool if lower order alloc failed or max vecs were requested */
 	if (bip == NULL) {
+		idx = BIOVEC_MAX_IDX;  /* so we free the payload properly later */
 		bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask);
 
 		if (unlikely(bip == NULL)) {

fs/bio.c

@@ -542,13 +542,18 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
 
 		if (page == prev->bv_page &&
 		    offset == prev->bv_offset + prev->bv_len) {
+			unsigned int prev_bv_len = prev->bv_len;
 			prev->bv_len += len;
 
 			if (q->merge_bvec_fn) {
 				struct bvec_merge_data bvm = {
+					/* prev_bvec is already charged in
+					   bi_size, discharge it in order to
+					   simulate merging updated prev_bvec
+					   as new bvec. */
 					.bi_bdev = bio->bi_bdev,
 					.bi_sector = bio->bi_sector,
-					.bi_size = bio->bi_size,
+					.bi_size = bio->bi_size - prev_bv_len,
 					.bi_rw = bio->bi_rw,
 				};