Merge branch 'for-4.12/block' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:

 - Add BFQ IO scheduler under the new blk-mq scheduling framework. BFQ
   was initially a fork of CFQ, but subsequently changed to implement
   fairness based on B-WF2Q+, a modified variant of WF2Q. BFQ is meant
   to be used on desktop type single drives, providing good fairness.
   From Paolo.

 - Add Kyber IO scheduler. This is a full multiqueue aware scheduler,
   using a scalable token based algorithm that throttles IO based on
   live completion IO stats, similary to blk-wbt. From Omar.

 - A series from Jan, moving users to separately allocated backing
   devices. This continues the work of separating backing device life
   times, solving various problems with hot removal.

 - A series of updates for lightnvm, mostly from Javier. Includes a
   'pblk' target that exposes an open channel SSD as a physical block
   device.

 - A series of fixes and improvements for nbd from Josef.

 - A series from Omar, removing queue sharing between devices on mostly
   legacy drivers. This helps us clean up other bits, if we know that a
   queue only has a single device backing. This has been overdue for
   more than a decade.

 - Fixes for the blk-stats, and improvements to unify the stats and user
   windows. This both improves blk-wbt, and enables other users to
   register a need to receive IO stats for a device. From Omar.

 - blk-throttle improvements from Shaohua. This provides a scalable
   framework for implementing scalable priotization - particularly for
   blk-mq, but applicable to any type of block device. The interface is
   marked experimental for now.

 - Bucketized IO stats for IO polling from Stephen Bates. This improves
   efficiency of polled workloads in the presence of mixed block size
   IO.

 - A few fixes for opal, from Scott.

 - A few pulls for NVMe, including a lot of fixes for NVMe-over-fabrics.
   From a variety of folks, mostly Sagi and James Smart.

 - A series from Bart, improving our exposed info and capabilities from
   the blk-mq debugfs support.

 - A series from Christoph, cleaning up how handle WRITE_ZEROES.

 - A series from Christoph, cleaning up the block layer handling of how
   we track errors in a request. On top of being a nice cleanup, it also
   shrinks the size of struct request a bit.

 - Removal of mg_disk and hd (sorry Linus) by Christoph. The former was
   never used by platforms, and the latter has outlived it's usefulness.

 - Various little bug fixes and cleanups from a wide variety of folks.

* 'for-4.12/block' of git://git.kernel.dk/linux-block: (329 commits)
  block: hide badblocks attribute by default
  blk-mq: unify hctx delay_work and run_work
  block: add kblock_mod_delayed_work_on()
  blk-mq: unify hctx delayed_run_work and run_work
  nbd: fix use after free on module unload
  MAINTAINERS: bfq: Add Paolo as maintainer for the BFQ I/O scheduler
  blk-mq-sched: alloate reserved tags out of normal pool
  mtip32xx: use runtime tag to initialize command header
  scsi: Implement blk_mq_ops.show_rq()
  blk-mq: Add blk_mq_ops.show_rq()
  blk-mq: Show operation, cmd_flags and rq_flags names
  blk-mq: Make blk_flags_show() callers append a newline character
  blk-mq: Move the "state" debugfs attribute one level down
  blk-mq: Unregister debugfs attributes earlier
  blk-mq: Only unregister hctxs for which registration succeeded
  blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
  blk-mq: Let blk_mq_debugfs_register() look up the queue name
  blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
  ide-pm: always pass 0 error to ide_complete_rq in ide_do_devset
  ide-pm: always pass 0 error to __blk_end_request_all
  ..

1 files changed, 53 insertions, 39 deletions

diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
index c7b0b6a52708..304f1c87c160 100644
--- a/drivers/nvme/target/loop.c
+++ b/drivers/nvme/target/loop.c
@@ -13,12 +13,10 @@
  */
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 #include <linux/scatterlist.h>
-#include <linux/delay.h>
 #include <linux/blk-mq.h>
 #include <linux/nvme.h>
 #include <linux/module.h>
 #include <linux/parser.h>
-#include <linux/t10-pi.h>
 #include "nvmet.h"
 #include "../host/nvme.h"
 #include "../host/fabrics.h"
@@ -93,31 +91,26 @@ static inline int nvme_loop_queue_idx(struct nvme_loop_queue *queue)
 static void nvme_loop_complete_rq(struct request *req)
 {
 	struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req);
-	int error = 0;
 
 	nvme_cleanup_cmd(req);
 	sg_free_table_chained(&iod->sg_table, true);
+	nvme_complete_rq(req);
+}
 
-	if (unlikely(req->errors)) {
-		if (nvme_req_needs_retry(req, req->errors)) {
-			nvme_requeue_req(req);
-			return;
-		}
-
-		if (blk_rq_is_passthrough(req))
-			error = req->errors;
-		else
-			error = nvme_error_status(req->errors);
-	}
+static struct blk_mq_tags *nvme_loop_tagset(struct nvme_loop_queue *queue)
+{
+	u32 queue_idx = nvme_loop_queue_idx(queue);
 
-	blk_mq_end_request(req, error);
+	if (queue_idx == 0)
+		return queue->ctrl->admin_tag_set.tags[queue_idx];
+	return queue->ctrl->tag_set.tags[queue_idx - 1];
 }
 
 static void nvme_loop_queue_response(struct nvmet_req *req)
 {
-	struct nvme_loop_iod *iod =
-		container_of(req, struct nvme_loop_iod, req);
-	struct nvme_completion *cqe = &iod->rsp;
+	struct nvme_loop_queue *queue =
+		container_of(req->sq, struct nvme_loop_queue, nvme_sq);
+	struct nvme_completion *cqe = req->rsp;
 
 	/*
 	 * AEN requests are special as they don't time out and can
@@ -125,15 +118,22 @@ static void nvme_loop_queue_response(struct nvmet_req *req)
 	 * aborts.  We don't even bother to allocate a struct request
 	 * for them but rather special case them here.
 	 */
-	if (unlikely(nvme_loop_queue_idx(iod->queue) == 0 &&
+	if (unlikely(nvme_loop_queue_idx(queue) == 0 &&
 			cqe->command_id >= NVME_LOOP_AQ_BLKMQ_DEPTH)) {
-		nvme_complete_async_event(&iod->queue->ctrl->ctrl, cqe->status,
+		nvme_complete_async_event(&queue->ctrl->ctrl, cqe->status,
 				&cqe->result);
 	} else {
-		struct request *rq = blk_mq_rq_from_pdu(iod);
+		struct request *rq;
+
+		rq = blk_mq_tag_to_rq(nvme_loop_tagset(queue), cqe->command_id);
+		if (!rq) {
+			dev_err(queue->ctrl->ctrl.device,
+				"tag 0x%x on queue %d not found\n",
+				cqe->command_id, nvme_loop_queue_idx(queue));
+			return;
+		}
 
-		iod->nvme_req.result = cqe->result;
-		blk_mq_complete_request(rq, le16_to_cpu(cqe->status) >> 1);
+		nvme_end_request(rq, cqe->status, cqe->result);
 	}
 }
 
@@ -154,7 +154,7 @@ nvme_loop_timeout(struct request *rq, bool reserved)
 	schedule_work(&iod->queue->ctrl->reset_work);
 
 	/* fail with DNR on admin cmd timeout */
-	rq->errors = NVME_SC_ABORT_REQ | NVME_SC_DNR;
+	nvme_req(rq)->status = NVME_SC_ABORT_REQ | NVME_SC_DNR;
 
 	return BLK_EH_HANDLED;
 }
@@ -268,7 +268,7 @@ static int nvme_loop_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data,
 	return 0;
 }
 
-static struct blk_mq_ops nvme_loop_mq_ops = {
+static const struct blk_mq_ops nvme_loop_mq_ops = {
 	.queue_rq	= nvme_loop_queue_rq,
 	.complete	= nvme_loop_complete_rq,
 	.init_request	= nvme_loop_init_request,
@@ -276,7 +276,7 @@ static struct blk_mq_ops nvme_loop_mq_ops = {
 	.timeout	= nvme_loop_timeout,
 };
 
-static struct blk_mq_ops nvme_loop_admin_mq_ops = {
+static const struct blk_mq_ops nvme_loop_admin_mq_ops = {
 	.queue_rq	= nvme_loop_queue_rq,
 	.complete	= nvme_loop_complete_rq,
 	.init_request	= nvme_loop_init_admin_request,
@@ -349,6 +349,19 @@ out_destroy_queues:
 	return ret;
 }
 
+static int nvme_loop_connect_io_queues(struct nvme_loop_ctrl *ctrl)
+{
+	int i, ret;
+
+	for (i = 1; i < ctrl->queue_count; i++) {
+		ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 static int nvme_loop_configure_admin_queue(struct nvme_loop_ctrl *ctrl)
 {
 	int error;
@@ -490,7 +503,7 @@ static void nvme_loop_reset_ctrl_work(struct work_struct *work)
 	struct nvme_loop_ctrl *ctrl = container_of(work,
 					struct nvme_loop_ctrl, reset_work);
 	bool changed;
-	int i, ret;
+	int ret;
 
 	nvme_loop_shutdown_ctrl(ctrl);
 
@@ -502,11 +515,9 @@ static void nvme_loop_reset_ctrl_work(struct work_struct *work)
 	if (ret)
 		goto out_destroy_admin;
 
-	for (i = 1; i < ctrl->queue_count; i++) {
-		ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
-		if (ret)
-			goto out_destroy_io;
-	}
+	ret = nvme_loop_connect_io_queues(ctrl);
+	if (ret)
+		goto out_destroy_io;
 
 	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
 	WARN_ON_ONCE(!changed);
@@ -559,7 +570,7 @@ static const struct nvme_ctrl_ops nvme_loop_ctrl_ops = {
 
 static int nvme_loop_create_io_queues(struct nvme_loop_ctrl *ctrl)
 {
-	int ret, i;
+	int ret;
 
 	ret = nvme_loop_init_io_queues(ctrl);
 	if (ret)
@@ -588,11 +599,9 @@ static int nvme_loop_create_io_queues(struct nvme_loop_ctrl *ctrl)
 		goto out_free_tagset;
 	}
 
-	for (i = 1; i < ctrl->queue_count; i++) {
-		ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
-		if (ret)
-			goto out_cleanup_connect_q;
-	}
+	ret = nvme_loop_connect_io_queues(ctrl);
+	if (ret)
+		goto out_cleanup_connect_q;
 
 	return 0;
 
@@ -736,7 +745,12 @@ static int __init nvme_loop_init_module(void)
 	ret = nvmet_register_transport(&nvme_loop_ops);
 	if (ret)
 		return ret;
-	return nvmf_register_transport(&nvme_loop_transport);
+
+	ret = nvmf_register_transport(&nvme_loop_transport);
+	if (ret)
+		nvmet_unregister_transport(&nvme_loop_ops);
+
+	return ret;
 }
 
 static void __exit nvme_loop_cleanup_module(void)