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

Pull block fixes from Jens Axboe:
 "Here's the second round of block updates for this merge window.

  It's a mix of fixes for changes that went in previously in this round,
  and fixes in general.  This pull request contains:

   - Fixes for loop from Christoph

   - A bdi vs gendisk lifetime fix from Dan, worth two cookies.

   - A blk-mq timeout fix, when on frozen queues.  From Gabriel.

   - Writeback fix from Jan, ensuring that __writeback_single_inode()
     does the right thing.

   - Fix for bio->bi_rw usage in f2fs from me.

   - Error path deadlock fix in blk-mq sysfs registration from me.

   - Floppy O_ACCMODE fix from Jiri.

   - Fix to the new bio op methods from Mike.

     One more followup will be coming here, ensuring that we don't
     propagate the block types outside of block.  That, and a rename of
     bio->bi_rw is coming right after -rc1 is cut.

   - Various little fixes"

* 'for-linus' of git://git.kernel.dk/linux-block:
  mm/block: convert rw_page users to bio op use
  loop: make do_req_filebacked more robust
  loop: don't try to use AIO for discards
  blk-mq: fix deadlock in blk_mq_register_disk() error path
  Include: blkdev: Removed duplicate 'struct request;' declaration.
  Fixup direct bi_rw modifiers
  block: fix bdi vs gendisk lifetime mismatch
  blk-mq: Allow timeouts to run while queue is freezing
  nbd: fix race in ioctl
  block: fix use-after-free in seq file
  f2fs: drop bio->bi_rw manual assignment
  block: add missing group association in bio-cloning functions
  blkcg: kill unused field nr_undestroyed_grps
  writeback: Write dirty times for WB_SYNC_ALL writeback
  floppy: fix open(O_ACCMODE) for ioctl-only open

1 files changed, 30 insertions, 37 deletions

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 075377eee0c0..c9f2107f7095 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -510,14 +510,10 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd,
 	return 0;
 }
 
-
-static inline int lo_rw_simple(struct loop_device *lo,
-		struct request *rq, loff_t pos, bool rw)
+static int do_req_filebacked(struct loop_device *lo, struct request *rq)
 {
 	struct loop_cmd *cmd = blk_mq_rq_to_pdu(rq);
-
-	if (cmd->use_aio)
-		return lo_rw_aio(lo, cmd, pos, rw);
+	loff_t pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
 
 	/*
 	 * lo_write_simple and lo_read_simple should have been covered
@@ -528,37 +524,30 @@ static inline int lo_rw_simple(struct loop_device *lo,
 	 * of the req at one time. And direct read IO doesn't need to
 	 * run flush_dcache_page().
 	 */
-	if (rw == WRITE)
-		return lo_write_simple(lo, rq, pos);
-	else
-		return lo_read_simple(lo, rq, pos);
-}
-
-static int do_req_filebacked(struct loop_device *lo, struct request *rq)
-{
-	loff_t pos;
-	int ret;
-
-	pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
-
-	if (op_is_write(req_op(rq))) {
-		if (req_op(rq) == REQ_OP_FLUSH)
-			ret = lo_req_flush(lo, rq);
-		else if (req_op(rq) == REQ_OP_DISCARD)
-			ret = lo_discard(lo, rq, pos);
-		else if (lo->transfer)
-			ret = lo_write_transfer(lo, rq, pos);
+	switch (req_op(rq)) {
+	case REQ_OP_FLUSH:
+		return lo_req_flush(lo, rq);
+	case REQ_OP_DISCARD:
+		return lo_discard(lo, rq, pos);
+	case REQ_OP_WRITE:
+		if (lo->transfer)
+			return lo_write_transfer(lo, rq, pos);
+		else if (cmd->use_aio)
+			return lo_rw_aio(lo, cmd, pos, WRITE);
 		else
-			ret = lo_rw_simple(lo, rq, pos, WRITE);
-
-	} else {
+			return lo_write_simple(lo, rq, pos);
+	case REQ_OP_READ:
 		if (lo->transfer)
-			ret = lo_read_transfer(lo, rq, pos);
+			return lo_read_transfer(lo, rq, pos);
+		else if (cmd->use_aio)
+			return lo_rw_aio(lo, cmd, pos, READ);
 		else
-			ret = lo_rw_simple(lo, rq, pos, READ);
+			return lo_read_simple(lo, rq, pos);
+	default:
+		WARN_ON_ONCE(1);
+		return -EIO;
+		break;
 	}
-
-	return ret;
 }
 
 struct switch_request {
@@ -1659,11 +1648,15 @@ static int loop_queue_rq(struct blk_mq_hw_ctx *hctx,
 	if (lo->lo_state != Lo_bound)
 		return -EIO;
 
-	if (lo->use_dio && (req_op(cmd->rq) != REQ_OP_FLUSH ||
-	    req_op(cmd->rq) == REQ_OP_DISCARD))
-		cmd->use_aio = true;
-	else
+	switch (req_op(cmd->rq)) {
+	case REQ_OP_FLUSH:
+	case REQ_OP_DISCARD:
 		cmd->use_aio = false;
+		break;
+	default:
+		cmd->use_aio = lo->use_dio;
+		break;
+	}
 
 	queue_kthread_work(&lo->worker, &cmd->work);