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

Pull block fixes from Jens Axboe:
 "A collection of fixes from this series.  The most important here is a
  regression fix for an issue that some folks would hit in blk-merge.c,
  and the NVMe queue depth limit for the screwed up Apple "nvme"
  controller.

  In more detail, this pull request contains:

   - a set of fixes for null_blk, including a fix for a few corner cases
     where we could hang the device.  From Arianna and Paolo.

   - lightnvm:
        - A build improvement from Keith.
        - Update the qemu pci id detection from Matias.
        - Error handling fixes for leaks and other little fixes from
          Sudip and Wenwei.

   - fix from Eric where BLKRRPART would not return EBUSY for whole
     device mounts, only when partitions were mounted.

   - fix from Jan Kara, where EOF O_DIRECT reads would return
     negatively.

   - remove check for rq_mergeable() when checking limits for cloned
     requests.  The check doesn't make any sense.  It's assuming that
     since NOMERGE is set on the request that we don't have to
     recalculate limits since the request didn't change, but that's not
     true if the request has been redirected.  From Hannes.

   - correctly get the bio front segment value set for single segment
     bio's, fixing a BUG() in blk-merge.  From Ming"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme: temporary fix for Apple controller reset
  null_blk: change type of completion_nsec to unsigned long
  null_blk: guarantee device restart in all irq modes
  null_blk: set a separate timer for each command
  blk-merge: fix computing bio->bi_seg_front_size in case of single segment
  direct-io: Fix negative return from dio read beyond eof
  block: Always check queue limits for cloned requests
  lightnvm: missing nvm_lock acquire
  lightnvm: unconverted ppa returned in get_bb_tbl
  lightnvm: refactor and change vendor id for qemu
  lightnvm: do device max sectors boundary check first
  lightnvm: fix ioctl memory leaks
  lightnvm: free memory when gennvm register fails
  lightnvm: Simplify config when disabled
  Return EBUSY from BLKRRPART for mounted whole-dev fs

3 files changed, 11 insertions, 15 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index 5131993b..a0af404 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -2114,7 +2114,8 @@ blk_qc_t submit_bio(int rw, struct bio *bio)
 EXPORT_SYMBOL(submit_bio);
 
 /**
- * blk_rq_check_limits - Helper function to check a request for the queue limit
+ * blk_cloned_rq_check_limits - Helper function to check a cloned request
+ *                              for new the queue limits
  * @q:  the queue
  * @rq: the request being checked
  *
@@ -2125,20 +2126,13 @@ EXPORT_SYMBOL(submit_bio);
  *    after it is inserted to @q, it should be checked against @q before
  *    the insertion using this generic function.
  *
- *    This function should also be useful for request stacking drivers
- *    in some cases below, so export this function.
  *    Request stacking drivers like request-based dm may change the queue
- *    limits while requests are in the queue (e.g. dm's table swapping).
- *    Such request stacking drivers should check those requests against
- *    the new queue limits again when they dispatch those requests,
- *    although such checkings are also done against the old queue limits
- *    when submitting requests.
+ *    limits when retrying requests on other queues. Those requests need
+ *    to be checked against the new queue limits again during dispatch.
  */
-int blk_rq_check_limits(struct request_queue *q, struct request *rq)
+static int blk_cloned_rq_check_limits(struct request_queue *q,
+				      struct request *rq)
 {
-	if (!rq_mergeable(rq))
-		return 0;
-
 	if (blk_rq_sectors(rq) > blk_queue_get_max_sectors(q, rq->cmd_flags)) {
 		printk(KERN_ERR "%s: over max size limit.\n", __func__);
 		return -EIO;
@@ -2158,7 +2152,6 @@ int blk_rq_check_limits(struct request_queue *q, struct request *rq)
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(blk_rq_check_limits);
 
 /**
  * blk_insert_cloned_request - Helper for stacking drivers to submit a request
@@ -2170,7 +2163,7 @@ int blk_insert_cloned_request(struct request_queue *q, struct request *rq)
 	unsigned long flags;
 	int where = ELEVATOR_INSERT_BACK;
 
-	if (blk_rq_check_limits(q, rq))
+	if (blk_cloned_rq_check_limits(q, rq))
 		return -EIO;
 
 	if (rq->rq_disk &&
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 41a55ba..e01405a 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -103,6 +103,9 @@ static struct bio *blk_bio_segment_split(struct request_queue *q,
 			bvprv = bv;
 			bvprvp = &bvprv;
 			sectors += bv.bv_len >> 9;
+
+			if (nsegs == 1 && seg_size > front_seg_size)
+				front_seg_size = seg_size;
 			continue;
 		}
 new_segment:
diff --git a/block/partition-generic.c b/block/partition-generic.c
index 3b03015..746935a 100644
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -397,7 +397,7 @@ static int drop_partitions(struct gendisk *disk, struct block_device *bdev)
 	struct hd_struct *part;
 	int res;
 
-	if (bdev->bd_part_count)
+	if (bdev->bd_part_count || bdev->bd_super)
 		return -EBUSY;
 	res = invalidate_partition(disk, 0);
 	if (res)