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

Pull block fixes from Jens Axboe:
 "Make the block layer great again.

  Basically three amazing fixes in this pull request, split into 4
  patches.  Believe me, they should go into 4.4.  Two of them fix a
  regression, the third and last fixes an easy-to-trigger bug.

   - Fix a bad irq enable through null_blk, for queue_mode=1 and using
     timer completions.  Add a block helper to restart a queue
     asynchronously, and use that from null_blk.  From me.

   - Fix a performance issue in NVMe.  Some devices (Intel Pxxxx) expose
     a stripe boundary, and performance suffers if we cross it.  We took
     that into account for merging, but not for the newer splitting
     code.  Fix from Keith.

   - Fix a kernel oops in lightnvm with multiple channels.  From Matias"

* 'for-linus' of git://git.kernel.dk/linux-block:
  lightnvm: wrong offset in bad blk lun calculation
  null_blk: use async queue restart helper
  block: add blk_start_queue_async()
  block: Split bios on chunk boundaries

5 files changed, 24 insertions, 8 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index c487b94c59e3..33e2f62d5062 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -207,6 +207,22 @@ void blk_delay_queue(struct request_queue *q, unsigned long msecs)
 EXPORT_SYMBOL(blk_delay_queue);
 
 /**
+ * blk_start_queue_async - asynchronously restart a previously stopped queue
+ * @q:    The &struct request_queue in question
+ *
+ * Description:
+ *   blk_start_queue_async() will clear the stop flag on the queue, and
+ *   ensure that the request_fn for the queue is run from an async
+ *   context.
+ **/
+void blk_start_queue_async(struct request_queue *q)
+{
+        queue_flag_clear(QUEUE_FLAG_STOPPED, q);
+        blk_run_queue_async(q);
+}
+EXPORT_SYMBOL(blk_start_queue_async);
+
+/**
  * blk_start_queue - restart a previously stopped queue
  * @q:    The &struct request_queue in question
  *
diff --git a/block/blk-merge.c b/block/blk-merge.c
index e01405a3e8b3..e73846a3d08a 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -81,7 +81,7 @@ static struct bio *blk_bio_segment_split(struct request_queue *q,
         struct bio *new = NULL;
 
         bio_for_each_segment(bv, bio, iter) {
-                if (sectors + (bv.bv_len >> 9) > queue_max_sectors(q))
+                if (sectors + (bv.bv_len >> 9) > blk_max_size_offset(q, bio->bi_iter.bi_sector))
                         goto split;
 
                 /*
diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index a428e4ef71fd..09e3c0d87ecc 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -232,20 +232,19 @@ static void end_cmd(struct nullb_cmd *cmd)
                 break;
         case NULL_Q_BIO:
                 bio_endio(cmd->bio);
-                goto free_cmd;
+                break;
         }
 
+        free_cmd(cmd);
+
         /* Restart queue if needed, as we are freeing a tag */
-        if (q && !q->mq_ops && blk_queue_stopped(q)) {
+        if (queue_mode == NULL_Q_RQ && blk_queue_stopped(q)) {
                 unsigned long flags;
 
                 spin_lock_irqsave(q->queue_lock, flags);
-                if (blk_queue_stopped(q))
-                        blk_start_queue(q);
+                blk_start_queue_async(q);
                 spin_unlock_irqrestore(q->queue_lock, flags);
         }
-free_cmd:
-        free_cmd(cmd);
 }
 
 static enum hrtimer_restart null_cmd_timer_expired(struct hrtimer *timer)
diff --git a/drivers/lightnvm/gennvm.c b/drivers/lightnvm/gennvm.c
index f434e89e1c7a..a54b339951a3 100644
--- a/drivers/lightnvm/gennvm.c
+++ b/drivers/lightnvm/gennvm.c
@@ -75,7 +75,7 @@ static int gennvm_block_bb(struct ppa_addr ppa, int nr_blocks, u8 *blks,
         struct nvm_block *blk;
         int i;
 
-        lun = &gn->luns[(dev->nr_luns * ppa.g.ch) + ppa.g.lun];
+        lun = &gn->luns[(dev->luns_per_chnl * ppa.g.ch) + ppa.g.lun];
 
         for (i = 0; i < nr_blocks; i++) {
                 if (blks[i] == 0)
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 0169ba2e2e64..c70e3588a48c 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -797,6 +797,7 @@ extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
 extern int blk_queue_enter(struct request_queue *q, gfp_t gfp);
 extern void blk_queue_exit(struct request_queue *q);
 extern void blk_start_queue(struct request_queue *q);
+extern void blk_start_queue_async(struct request_queue *q);
 extern void blk_stop_queue(struct request_queue *q);
 extern void blk_sync_queue(struct request_queue *q);
 extern void __blk_stop_queue(struct request_queue *q);