Merge tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "This is the main pull request for block/storage for 4.21.

  Larger than usual, it was a busy round with lots of goodies queued up.
  Most notable is the removal of the old IO stack, which has been a long
  time coming. No new features for a while, everything coming in this
  week has all been fixes for things that were previously merged.

  This contains:

   - Use atomic counters instead of semaphores for mtip32xx (Arnd)

   - Cleanup of the mtip32xx request setup (Christoph)

   - Fix for circular locking dependency in loop (Jan, Tetsuo)

   - bcache (Coly, Guoju, Shenghui)
      * Optimizations for writeback caching
      * Various fixes and improvements

   - nvme (Chaitanya, Christoph, Sagi, Jay, me, Keith)
      * host and target support for NVMe over TCP
      * Error log page support
      * Support for separate read/write/poll queues
      * Much improved polling
      * discard OOM fallback
      * Tracepoint improvements

   - lightnvm (Hans, Hua, Igor, Matias, Javier)
      * Igor added packed metadata to pblk. Now drives without metadata
        per LBA can be used as well.
      * Fix from Geert on uninitialized value on chunk metadata reads.
      * Fixes from Hans and Javier to pblk recovery and write path.
      * Fix from Hua Su to fix a race condition in the pblk recovery
        code.
      * Scan optimization added to pblk recovery from Zhoujie.
      * Small geometry cleanup from me.

   - Conversion of the last few drivers that used the legacy path to
     blk-mq (me)

   - Removal of legacy IO path in SCSI (me, Christoph)

   - Removal of legacy IO stack and schedulers (me)

   - Support for much better polling, now without interrupts at all.
     blk-mq adds support for multiple queue maps, which enables us to
     have a map per type. This in turn enables nvme to have separate
     completion queues for polling, which can then be interrupt-less.
     Also means we're ready for async polled IO, which is hopefully
     coming in the next release.

   - Killing of (now) unused block exports (Christoph)

   - Unification of the blk-rq-qos and blk-wbt wait handling (Josef)

   - Support for zoned testing with null_blk (Masato)

   - sx8 conversion to per-host tag sets (Christoph)

   - IO priority improvements (Damien)

   - mq-deadline zoned fix (Damien)

   - Ref count blkcg series (Dennis)

   - Lots of blk-mq improvements and speedups (me)

   - sbitmap scalability improvements (me)

   - Make core inflight IO accounting per-cpu (Mikulas)

   - Export timeout setting in sysfs (Weiping)

   - Cleanup the direct issue path (Jianchao)

   - Export blk-wbt internals in block debugfs for easier debugging
     (Ming)

   - Lots of other fixes and improvements"

* tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block: (364 commits)
  kyber: use sbitmap add_wait_queue/list_del wait helpers
  sbitmap: add helpers for add/del wait queue handling
  block: save irq state in blkg_lookup_create()
  dm: don't reuse bio for flushes
  nvme-pci: trace SQ status on completions
  nvme-rdma: implement polling queue map
  nvme-fabrics: allow user to pass in nr_poll_queues
  nvme-fabrics: allow nvmf_connect_io_queue to poll
  nvme-core: optionally poll sync commands
  block: make request_to_qc_t public
  nvme-tcp: fix spelling mistake "attepmpt" -> "attempt"
  nvme-tcp: fix endianess annotations
  nvmet-tcp: fix endianess annotations
  nvme-pci: refactor nvme_poll_irqdisable to make sparse happy
  nvme-pci: only set nr_maps to 2 if poll queues are supported
  nvmet: use a macro for default error location
  nvmet: fix comparison of a u16 with -1
  blk-mq: enable IO poll if .nr_queues of type poll > 0
  blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight()
  blk-mq: skip zero-queue maps in blk_mq_map_swqueue
  ...

1 files changed, 12 insertions, 4 deletions

diff --git a/drivers/block/skd_main.c b/drivers/block/skd_main.c
index 2459dcc04b1c..a10d5736d8f7 100644
--- a/drivers/block/skd_main.c
+++ b/drivers/block/skd_main.c
@@ -181,6 +181,7 @@ struct skd_request_context {
 	struct fit_completion_entry_v1 completion;
 
 	struct fit_comp_error_info err_info;
+	int retries;
 
 	blk_status_t status;
 };
@@ -382,11 +383,12 @@ static void skd_log_skreq(struct skd_device *skdev,
  * READ/WRITE REQUESTS
  *****************************************************************************
  */
-static void skd_inc_in_flight(struct request *rq, void *data, bool reserved)
+static bool skd_inc_in_flight(struct request *rq, void *data, bool reserved)
 {
 	int *count = data;
 
 	count++;
+	return true;
 }
 
 static int skd_in_flight(struct skd_device *skdev)
@@ -494,6 +496,11 @@ static blk_status_t skd_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
 	if (unlikely(skdev->state != SKD_DRVR_STATE_ONLINE))
 		return skd_fail_all(q) ? BLK_STS_IOERR : BLK_STS_RESOURCE;
 
+	if (!(req->rq_flags & RQF_DONTPREP)) {
+		skreq->retries = 0;
+		req->rq_flags |= RQF_DONTPREP;
+	}
+
 	blk_mq_start_request(req);
 
 	WARN_ONCE(tag >= skd_max_queue_depth, "%#x > %#x (nr_requests = %lu)\n",
@@ -1425,7 +1432,7 @@ static void skd_resolve_req_exception(struct skd_device *skdev,
 		break;
 
 	case SKD_CHECK_STATUS_REQUEUE_REQUEST:
-		if ((unsigned long) ++req->special < SKD_MAX_RETRIES) {
+		if (++skreq->retries < SKD_MAX_RETRIES) {
 			skd_log_skreq(skdev, skreq, "retry");
 			blk_mq_requeue_request(req, true);
 			break;
@@ -1887,13 +1894,13 @@ static void skd_isr_fwstate(struct skd_device *skdev)
 		skd_skdev_state_to_str(skdev->state), skdev->state);
 }
 
-static void skd_recover_request(struct request *req, void *data, bool reserved)
+static bool skd_recover_request(struct request *req, void *data, bool reserved)
 {
 	struct skd_device *const skdev = data;
 	struct skd_request_context *skreq = blk_mq_rq_to_pdu(req);
 
 	if (skreq->state != SKD_REQ_STATE_BUSY)
-		return;
+		return true;
 
 	skd_log_skreq(skdev, skreq, "recover");
 
@@ -1904,6 +1911,7 @@ static void skd_recover_request(struct request *req, void *data, bool reserved)
 	skreq->state = SKD_REQ_STATE_IDLE;
 	skreq->status = BLK_STS_IOERR;
 	blk_mq_complete_request(req);
+	return true;
 }
 
 static void skd_recover_requests(struct skd_device *skdev)