[PATCH v2 0/6] blk-mq: Add a flag for reserved requests series

[PATCH v2 0/6] blk-mq: Add a flag for reserved requests series

[John Garry]

In [0] I included "blk-mq: Add a flag for reserved requests" to identify
if a request is 'reserved' for special handling. Doing this is easier than
passing a 'reserved' arg to the blk_mq_ops callbacks. Indeed, only 1x
timeout implementation or blk-mq iter function actually uses the
'reserved' arg (or 3x if you count SCSI core and FNIC SCSI driver). So
this series drops the 'reserved' arg for these timeout and iter functions.
Christoph suggested that I try to upstream now.

Differences to v1:
- Use "scsi_timeout" as name for SCSI timeout function and update docs
- Add RB tags (thanks!)
- Split out patch to drop local variables for 'reserved', as requested by
  Bart

Based on following:
6dbcddf6e76b (block/for-5.20/block) block: bfq: Fix kernel-doc headers

[0] https://lore.kernel.org/linux-scsi/1654770559-101375-1-git-send-email-john.garry@huawei.com/T/#m22aa9f89e55835edc2e650d43f7e3219a3a1a324

John Garry (6):
  scsi: core: Remove reserved request time-out handling
  blk-mq: Add a flag for reserved requests
  blk-mq: Drop blk_mq_ops.timeout 'reserved' arg
  scsi: fnic: Drop reserved request handling
  blk-mq: Drop 'reserved' arg of busy_tag_iter_fn
  blk-mq: Drop local variable for reserved tag

 Documentation/scsi/scsi_eh.rst          |  3 +--
 Documentation/scsi/scsi_mid_low_api.rst |  2 +-
 block/blk-mq-debugfs.c                  |  2 +-
 block/blk-mq-tag.c                      | 13 +++++--------
 block/blk-mq.c                          | 22 +++++++++++++---------
 block/bsg-lib.c                         |  2 +-
 drivers/block/mtip32xx/mtip32xx.c       | 11 +++++------
 drivers/block/nbd.c                     |  5 ++---
 drivers/block/null_blk/main.c           |  2 +-
 drivers/infiniband/ulp/srp/ib_srp.c     |  3 +--
 drivers/mmc/core/queue.c                |  3 +--
 drivers/nvme/host/apple.c               |  3 +--
 drivers/nvme/host/core.c                |  2 +-
 drivers/nvme/host/fc.c                  |  6 ++----
 drivers/nvme/host/nvme.h                |  2 +-
 drivers/nvme/host/pci.c                 |  2 +-
 drivers/nvme/host/rdma.c                |  3 +--
 drivers/nvme/host/tcp.c                 |  3 +--
 drivers/s390/block/dasd.c               |  2 +-
 drivers/s390/block/dasd_int.h           |  2 +-
 drivers/scsi/aacraid/comminit.c         |  2 +-
 drivers/scsi/aacraid/linit.c            |  2 +-
 drivers/scsi/fnic/fnic_scsi.c           | 14 ++++----------
 drivers/scsi/hosts.c                    | 14 ++++++--------
 drivers/scsi/mpi3mr/mpi3mr_os.c         | 16 ++++------------
 drivers/scsi/scsi_error.c               |  6 +++---
 drivers/scsi/scsi_lib.c                 |  8 --------
 drivers/scsi/scsi_priv.h                |  2 +-
 include/linux/blk-mq.h                  | 10 ++++++++--
 include/scsi/scsi_host.h                |  2 +-
 30 files changed, 71 insertions(+), 98 deletions(-)

-- 
2.25.1

[PATCH v2 1/6] scsi: core: Remove reserved request time-out handling

[John Garry]

The SCSI core code does not currently support reserved commands. As such,
requests which time-out would never be reserved, and scsi_timeout()
'reserved' arg should never be set.

Remove handling for reserved requests, drop the wrapper scsi_timeout()
as it now just calls scsi_times_out() always, and finally rename
scsi_times_out() -> scsi_timeout() to match the blk_mq_ops method name.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
---
 Documentation/scsi/scsi_eh.rst          | 3 +--
 Documentation/scsi/scsi_mid_low_api.rst | 2 +-
 drivers/scsi/scsi_error.c               | 7 ++++---
 drivers/scsi/scsi_lib.c                 | 8 --------
 drivers/scsi/scsi_priv.h                | 3 ++-
 5 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/Documentation/scsi/scsi_eh.rst b/Documentation/scsi/scsi_eh.rst
index 885395dc1f15..bad624fab823 100644
--- a/Documentation/scsi/scsi_eh.rst
+++ b/Documentation/scsi/scsi_eh.rst
@@ -87,8 +87,7 @@ with the command.
 1.2.2 Completing a scmd w/ timeout
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-The timeout handler is scsi_times_out().  When a timeout occurs, this
-function
+The timeout handler is scsi_timeout().  When a timeout occurs, this function
 
  1. invokes optional hostt->eh_timed_out() callback.  Return value can
     be one of
diff --git a/Documentation/scsi/scsi_mid_low_api.rst b/Documentation/scsi/scsi_mid_low_api.rst
index 63ddea2b9640..a8c5bd15a440 100644
--- a/Documentation/scsi/scsi_mid_low_api.rst
+++ b/Documentation/scsi/scsi_mid_low_api.rst
@@ -731,7 +731,7 @@ Details::
     *      Notes: If 'no_async_abort' is defined this callback
     *  	will be invoked from scsi_eh thread. No other commands
     *	will then be queued on current host during eh.
-    *	Otherwise it will be called whenever scsi_times_out()
+    *	Otherwise it will be called whenever scsi_timeout()
     *      is called due to a command timeout.
     *
     *      Optionally defined in: LLD
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 49ef864df581..a8b71b73a5a5 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -139,7 +139,7 @@ static bool scsi_eh_should_retry_cmd(struct scsi_cmnd *cmd)
  *
  * Note: this function must be called only for a command that has timed out.
  * Because the block layer marks a request as complete before it calls
- * scsi_times_out(), a .scsi_done() call from the LLD for a command that has
+ * scsi_timeout(), a .scsi_done() call from the LLD for a command that has
  * timed out do not have any effect. Hence it is safe to call
  * scsi_finish_command() from this function.
  */
@@ -316,8 +316,9 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
 }
 
 /**
- * scsi_times_out - Timeout function for normal scsi commands.
+ * scsi_timeout - Timeout function for normal scsi commands.
  * @req:	request that is timing out.
+ * @reserved:	whether the request is a reserved request.
  *
  * Notes:
  *     We do not need to lock this.  There is the potential for a race
@@ -325,7 +326,7 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
  *     normal completion function determines that the timer has already
  *     fired, then it mustn't do anything.
  */
-enum blk_eh_timer_return scsi_times_out(struct request *req)
+enum blk_eh_timer_return scsi_timeout(struct request *req, bool reserved)
 {
 	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
 	enum blk_eh_timer_return rtn = BLK_EH_DONE;
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 6ffc9e4258a8..8eb51ef7c077 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1790,14 +1790,6 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
 	return ret;
 }
 
-static enum blk_eh_timer_return scsi_timeout(struct request *req,
-		bool reserved)
-{
-	if (reserved)
-		return BLK_EH_RESET_TIMER;
-	return scsi_times_out(req);
-}
-
 static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
 				unsigned int hctx_idx, unsigned int numa_node)
 {
diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index 5c4786310a31..695d0c83ffe0 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -72,7 +72,8 @@ extern void scsi_exit_devinfo(void);
 
 /* scsi_error.c */
 extern void scmd_eh_abort_handler(struct work_struct *work);
-extern enum blk_eh_timer_return scsi_times_out(struct request *req);
+extern enum blk_eh_timer_return scsi_timeout(struct request *req,
+					     bool reserved);
 extern int scsi_error_handler(void *host);
 extern enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *cmd);
 extern void scsi_eh_wakeup(struct Scsi_Host *shost);
-- 
2.25.1

[PATCH v2 2/6] blk-mq: Add a flag for reserved requests

[John Garry]

Add a flag for reserved requests so that drivers may know this for any
special handling.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
---
 block/blk-mq.c         | 6 ++++++
 include/linux/blk-mq.h | 6 ++++++
 2 files changed, 12 insertions(+)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 5aa95964191b..d38c97fe89f5 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -474,6 +474,9 @@ static struct request *__blk_mq_alloc_requests(struct blk_mq_alloc_data *data)
 	if (!(data->rq_flags & RQF_ELV))
 		blk_mq_tag_busy(data->hctx);
 
+	if (data->flags & BLK_MQ_REQ_RESERVED)
+		data->rq_flags |= RQF_RESV;
+
 	/*
 	 * Try batched alloc if we want more than 1 tag.
 	 */
@@ -588,6 +591,9 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
 	else
 		data.rq_flags |= RQF_ELV;
 
+	if (flags & BLK_MQ_REQ_RESERVED)
+		data.rq_flags |= RQF_RESV;
+
 	ret = -EWOULDBLOCK;
 	tag = blk_mq_get_tag(&data);
 	if (tag == BLK_MQ_NO_TAG)
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index e2d9daf7e8dd..6d81fe10e850 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -57,6 +57,7 @@ typedef __u32 __bitwise req_flags_t;
 #define RQF_TIMED_OUT		((__force req_flags_t)(1 << 21))
 /* queue has elevator attached */
 #define RQF_ELV			((__force req_flags_t)(1 << 22))
+#define RQF_RESV			((__force req_flags_t)(1 << 23))
 
 /* flags that prevent us from merging requests: */
 #define RQF_NOMERGE_FLAGS \
@@ -823,6 +824,11 @@ static inline bool blk_mq_need_time_stamp(struct request *rq)
 	return (rq->rq_flags & (RQF_IO_STAT | RQF_STATS | RQF_ELV));
 }
 
+static inline bool blk_mq_is_reserved_rq(struct request *rq)
+{
+	return rq->rq_flags & RQF_RESV;
+}
+
 /*
  * Batched completions only work when there is no I/O error and no special
  * ->end_io handler.
-- 
2.25.1

[PATCH v2 3/6] blk-mq: Drop blk_mq_ops.timeout 'reserved' arg

[John Garry]

With new API blk_mq_is_reserved_rq() we can tell if a request is from
the reserved pool, so stop passing 'reserved' arg. There is actually
only a single user of that arg for all the callback implementations, which
can use blk_mq_is_reserved_rq() instead.

This will also allow us to stop passing the same 'reserved' around the
blk-mq iter functions next.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
---
 block/blk-mq.c                    | 6 +++---
 block/bsg-lib.c                   | 2 +-
 drivers/block/mtip32xx/mtip32xx.c | 5 ++---
 drivers/block/nbd.c               | 3 +--
 drivers/block/null_blk/main.c     | 2 +-
 drivers/mmc/core/queue.c          | 3 +--
 drivers/nvme/host/apple.c         | 3 +--
 drivers/nvme/host/fc.c            | 3 +--
 drivers/nvme/host/pci.c           | 2 +-
 drivers/nvme/host/rdma.c          | 3 +--
 drivers/nvme/host/tcp.c           | 3 +--
 drivers/s390/block/dasd.c         | 2 +-
 drivers/s390/block/dasd_int.h     | 2 +-
 drivers/scsi/scsi_error.c         | 3 +--
 drivers/scsi/scsi_priv.h          | 3 +--
 include/linux/blk-mq.h            | 2 +-
 16 files changed, 19 insertions(+), 28 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index d38c97fe89f5..81bd39e36e49 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1426,13 +1426,13 @@ bool blk_mq_queue_inflight(struct request_queue *q)
 }
 EXPORT_SYMBOL_GPL(blk_mq_queue_inflight);
 
-static void blk_mq_rq_timed_out(struct request *req, bool reserved)
+static void blk_mq_rq_timed_out(struct request *req)
 {
 	req->rq_flags |= RQF_TIMED_OUT;
 	if (req->q->mq_ops->timeout) {
 		enum blk_eh_timer_return ret;
 
-		ret = req->q->mq_ops->timeout(req, reserved);
+		ret = req->q->mq_ops->timeout(req);
 		if (ret == BLK_EH_DONE)
 			return;
 		WARN_ON_ONCE(ret != BLK_EH_RESET_TIMER);
@@ -1481,7 +1481,7 @@ static bool blk_mq_check_expired(struct request *rq, void *priv, bool reserved)
 	 * from blk_mq_check_expired().
 	 */
 	if (blk_mq_req_expired(rq, next))
-		blk_mq_rq_timed_out(rq, reserved);
+		blk_mq_rq_timed_out(rq);
 	return true;
 }
 
diff --git a/block/bsg-lib.c b/block/bsg-lib.c
index acfe1357bf6c..9570c77b9fe3 100644
--- a/block/bsg-lib.c
+++ b/block/bsg-lib.c
@@ -331,7 +331,7 @@ void bsg_remove_queue(struct request_queue *q)
 }
 EXPORT_SYMBOL_GPL(bsg_remove_queue);
 
-static enum blk_eh_timer_return bsg_timeout(struct request *rq, bool reserved)
+static enum blk_eh_timer_return bsg_timeout(struct request *rq)
 {
 	struct bsg_set *bset =
 		container_of(rq->q->tag_set, struct bsg_set, tag_set);
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 27386a572ba4..d5767215840c 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3487,12 +3487,11 @@ static int mtip_init_cmd(struct blk_mq_tag_set *set, struct request *rq,
 	return 0;
 }
 
-static enum blk_eh_timer_return mtip_cmd_timeout(struct request *req,
-								bool reserved)
+static enum blk_eh_timer_return mtip_cmd_timeout(struct request *req)
 {
 	struct driver_data *dd = req->q->queuedata;
 
-	if (reserved) {
+	if (blk_mq_is_reserved_rq(req)) {
 		struct mtip_cmd *cmd = blk_mq_rq_to_pdu(req);
 
 		cmd->status = BLK_STS_TIMEOUT;
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 07f3c139a3d7..166303716560 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -393,8 +393,7 @@ static u32 req_to_nbd_cmd_type(struct request *req)
 	}
 }
 
-static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
-						 bool reserved)
+static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req)
 {
 	struct nbd_cmd *cmd = blk_mq_rq_to_pdu(req);
 	struct nbd_device *nbd = cmd->nbd;
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 6b67088f4ea7..2d815d1eba25 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1578,7 +1578,7 @@ static int null_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob)
 	return nr;
 }
 
-static enum blk_eh_timer_return null_timeout_rq(struct request *rq, bool res)
+static enum blk_eh_timer_return null_timeout_rq(struct request *rq)
 {
 	struct blk_mq_hw_ctx *hctx = rq->mq_hctx;
 	struct nullb_cmd *cmd = blk_mq_rq_to_pdu(rq);
diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
index fa5324ceeebe..17236340dbd2 100644
--- a/drivers/mmc/core/queue.c
+++ b/drivers/mmc/core/queue.c
@@ -116,8 +116,7 @@ static enum blk_eh_timer_return mmc_cqe_timed_out(struct request *req)
 	}
 }
 
-static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req,
-						 bool reserved)
+static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req)
 {
 	struct request_queue *q = req->q;
 	struct mmc_queue *mq = q->queuedata;
diff --git a/drivers/nvme/host/apple.c b/drivers/nvme/host/apple.c
index d702d7d60235..495118ce958a 100644
--- a/drivers/nvme/host/apple.c
+++ b/drivers/nvme/host/apple.c
@@ -862,8 +862,7 @@ static void apple_nvme_disable(struct apple_nvme *anv, bool shutdown)
 	}
 }
 
-static enum blk_eh_timer_return apple_nvme_timeout(struct request *req,
-						   bool reserved)
+static enum blk_eh_timer_return apple_nvme_timeout(struct request *req)
 {
 	struct apple_nvme_iod *iod = blk_mq_rq_to_pdu(req);
 	struct apple_nvme_queue *q = iod->q;
diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
index 3c778bb0c294..a166c0b1cc33 100644
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -2565,8 +2565,7 @@ nvme_fc_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg)
 	nvme_reset_ctrl(&ctrl->ctrl);
 }
 
-static enum blk_eh_timer_return
-nvme_fc_timeout(struct request *rq, bool reserved)
+static enum blk_eh_timer_return nvme_fc_timeout(struct request *rq)
 {
 	struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(rq);
 	struct nvme_fc_ctrl *ctrl = op->ctrl;
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index c7012e85d035..83b1229a4e36 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1344,7 +1344,7 @@ static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
 		 "Try \"nvme_core.default_ps_max_latency_us=0 pcie_aspm=off\" and report a bug\n");
 }
 
-static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
+static enum blk_eh_timer_return nvme_timeout(struct request *req)
 {
 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
 	struct nvme_queue *nvmeq = iod->nvmeq;
diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index f2a5e1ea508a..d2fb8651e49d 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -2013,8 +2013,7 @@ static void nvme_rdma_complete_timed_out(struct request *rq)
 	nvmf_complete_timed_out_request(rq);
 }
 
-static enum blk_eh_timer_return
-nvme_rdma_timeout(struct request *rq, bool reserved)
+static enum blk_eh_timer_return nvme_rdma_timeout(struct request *rq)
 {
 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
 	struct nvme_rdma_queue *queue = req->queue;
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index bb67538d241b..f21f7b0140f9 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -2321,8 +2321,7 @@ static void nvme_tcp_complete_timed_out(struct request *rq)
 	nvmf_complete_timed_out_request(rq);
 }
 
-static enum blk_eh_timer_return
-nvme_tcp_timeout(struct request *rq, bool reserved)
+static enum blk_eh_timer_return nvme_tcp_timeout(struct request *rq)
 {
 	struct nvme_tcp_request *req = blk_mq_rq_to_pdu(rq);
 	struct nvme_ctrl *ctrl = &req->queue->ctrl->ctrl;
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index ba6d78789660..35d6f62ed515 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -3145,7 +3145,7 @@ static blk_status_t do_dasd_request(struct blk_mq_hw_ctx *hctx,
  * BLK_EH_DONE if the request is handled or terminated
  *		      by the driver.
  */
-enum blk_eh_timer_return dasd_times_out(struct request *req, bool reserved)
+enum blk_eh_timer_return dasd_times_out(struct request *req)
 {
 	struct dasd_block *block = req->q->queuedata;
 	struct dasd_device *device;
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index 83b918b84b4a..333a399f754e 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -795,7 +795,7 @@ void dasd_free_device(struct dasd_device *);
 struct dasd_block *dasd_alloc_block(void);
 void dasd_free_block(struct dasd_block *);
 
-enum blk_eh_timer_return dasd_times_out(struct request *req, bool reserved);
+enum blk_eh_timer_return dasd_times_out(struct request *req);
 
 void dasd_enable_device(struct dasd_device *);
 void dasd_set_target_state(struct dasd_device *, int);
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index a8b71b73a5a5..266ce414589c 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -318,7 +318,6 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
 /**
  * scsi_timeout - Timeout function for normal scsi commands.
  * @req:	request that is timing out.
- * @reserved:	whether the request is a reserved request.
  *
  * Notes:
  *     We do not need to lock this.  There is the potential for a race
@@ -326,7 +325,7 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
  *     normal completion function determines that the timer has already
  *     fired, then it mustn't do anything.
  */
-enum blk_eh_timer_return scsi_timeout(struct request *req, bool reserved)
+enum blk_eh_timer_return scsi_timeout(struct request *req)
 {
 	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
 	enum blk_eh_timer_return rtn = BLK_EH_DONE;
diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index 695d0c83ffe0..6eeaa0a7f86d 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -72,8 +72,7 @@ extern void scsi_exit_devinfo(void);
 
 /* scsi_error.c */
 extern void scmd_eh_abort_handler(struct work_struct *work);
-extern enum blk_eh_timer_return scsi_timeout(struct request *req,
-					     bool reserved);
+extern enum blk_eh_timer_return scsi_timeout(struct request *req);
 extern int scsi_error_handler(void *host);
 extern enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *cmd);
 extern void scsi_eh_wakeup(struct Scsi_Host *shost);
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 6d81fe10e850..fbb08bdd4618 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -575,7 +575,7 @@ struct blk_mq_ops {
 	/**
 	 * @timeout: Called on request timeout.
 	 */
-	enum blk_eh_timer_return (*timeout)(struct request *, bool);
+	enum blk_eh_timer_return (*timeout)(struct request *);
 
 	/**
 	 * @poll: Called to poll for completion of a specific tag.
-- 
2.25.1

[PATCH v2 4/6] scsi: fnic: Drop reserved request handling

[John Garry]

The SCSI core code does not support reserved requests, so drop the
handling in fnic_pending_aborts_iter().

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
---
 drivers/scsi/fnic/fnic_scsi.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/scsi/fnic/fnic_scsi.c b/drivers/scsi/fnic/fnic_scsi.c
index 3d64877bda8d..e7b7f6d73429 100644
--- a/drivers/scsi/fnic/fnic_scsi.c
+++ b/drivers/scsi/fnic/fnic_scsi.c
@@ -2019,8 +2019,6 @@ static bool fnic_pending_aborts_iter(struct scsi_cmnd *sc,
 
 	if (sc == iter_data->lr_sc || sc->device != lun_dev)
 		return true;
-	if (reserved)
-		return true;
 
 	io_lock = fnic_io_lock_tag(fnic, abt_tag);
 	spin_lock_irqsave(io_lock, flags);
-- 
2.25.1

[PATCH v2 5/6] blk-mq: Drop 'reserved' arg of busy_tag_iter_fn

[John Garry]

We no longer use the 'reserved' arg in busy_tag_iter_fn for any iter
function so it may be dropped.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
---
 block/blk-mq-debugfs.c              |  2 +-
 block/blk-mq-tag.c                  |  7 +++----
 block/blk-mq.c                      | 10 ++++------
 drivers/block/mtip32xx/mtip32xx.c   |  6 +++---
 drivers/block/nbd.c                 |  2 +-
 drivers/infiniband/ulp/srp/ib_srp.c |  3 +--
 drivers/nvme/host/core.c            |  2 +-
 drivers/nvme/host/fc.c              |  3 +--
 drivers/nvme/host/nvme.h            |  2 +-
 drivers/scsi/aacraid/comminit.c     |  2 +-
 drivers/scsi/aacraid/linit.c        |  2 +-
 drivers/scsi/fnic/fnic_scsi.c       | 12 ++++--------
 drivers/scsi/hosts.c                | 14 ++++++--------
 drivers/scsi/mpi3mr/mpi3mr_os.c     | 16 ++++------------
 include/linux/blk-mq.h              |  2 +-
 include/scsi/scsi_host.h            |  2 +-
 16 files changed, 34 insertions(+), 53 deletions(-)

diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 7e4136a60e1c..d976920d4331 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -377,7 +377,7 @@ struct show_busy_params {
  * e.g. due to a concurrent blk_mq_finish_request() call. Returns true to
  * keep iterating requests.
  */
-static bool hctx_show_busy_rq(struct request *rq, void *data, bool reserved)
+static bool hctx_show_busy_rq(struct request *rq, void *data)
 {
 	const struct show_busy_params *params = data;
 
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 2dcd738c6952..509c35f080a9 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -287,7 +287,7 @@ static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
 		return true;
 
 	if (rq->q == q && (!hctx || rq->mq_hctx == hctx))
-		ret = iter_data->fn(rq, iter_data->data, reserved);
+		ret = iter_data->fn(rq, iter_data->data);
 	blk_mq_put_rq_ref(rq);
 	return ret;
 }
@@ -358,7 +358,7 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
 
 	if (!(iter_data->flags & BT_TAG_ITER_STARTED) ||
 	    blk_mq_request_started(rq))
-		ret = iter_data->fn(rq, iter_data->data, reserved);
+		ret = iter_data->fn(rq, iter_data->data);
 	if (!iter_static_rqs)
 		blk_mq_put_rq_ref(rq);
 	return ret;
@@ -448,8 +448,7 @@ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
 }
 EXPORT_SYMBOL(blk_mq_tagset_busy_iter);
 
-static bool blk_mq_tagset_count_completed_rqs(struct request *rq,
-		void *data, bool reserved)
+static bool blk_mq_tagset_count_completed_rqs(struct request *rq, void *data)
 {
 	unsigned *count = data;
 
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 81bd39e36e49..b805a563aa85 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -128,8 +128,7 @@ struct mq_inflight {
 	unsigned int inflight[2];
 };
 
-static bool blk_mq_check_inflight(struct request *rq, void *priv,
-				  bool reserved)
+static bool blk_mq_check_inflight(struct request *rq, void *priv)
 {
 	struct mq_inflight *mi = priv;
 
@@ -1399,8 +1398,7 @@ void blk_mq_delay_kick_requeue_list(struct request_queue *q,
 }
 EXPORT_SYMBOL(blk_mq_delay_kick_requeue_list);
 
-static bool blk_mq_rq_inflight(struct request *rq, void *priv,
-			       bool reserved)
+static bool blk_mq_rq_inflight(struct request *rq, void *priv)
 {
 	/*
 	 * If we find a request that isn't idle we know the queue is busy
@@ -1469,7 +1467,7 @@ void blk_mq_put_rq_ref(struct request *rq)
 		__blk_mq_free_request(rq);
 }
 
-static bool blk_mq_check_expired(struct request *rq, void *priv, bool reserved)
+static bool blk_mq_check_expired(struct request *rq, void *priv)
 {
 	unsigned long *next = priv;
 
@@ -3277,7 +3275,7 @@ struct rq_iter_data {
 	bool has_rq;
 };
 
-static bool blk_mq_has_request(struct request *rq, void *data, bool reserved)
+static bool blk_mq_has_request(struct request *rq, void *data)
 {
 	struct rq_iter_data *iter_data = data;
 
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index d5767215840c..5ae0e9bb08be 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -2556,7 +2556,7 @@ static void mtip_softirq_done_fn(struct request *rq)
 	blk_mq_end_request(rq, cmd->status);
 }
 
-static bool mtip_abort_cmd(struct request *req, void *data, bool reserved)
+static bool mtip_abort_cmd(struct request *req, void *data)
 {
 	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(req);
 	struct driver_data *dd = data;
@@ -2569,7 +2569,7 @@ static bool mtip_abort_cmd(struct request *req, void *data, bool reserved)
 	return true;
 }
 
-static bool mtip_queue_cmd(struct request *req, void *data, bool reserved)
+static bool mtip_queue_cmd(struct request *req, void *data)
 {
 	struct driver_data *dd = data;
 
@@ -3672,7 +3672,7 @@ static int mtip_block_initialize(struct driver_data *dd)
 	return rv;
 }
 
-static bool mtip_no_dev_cleanup(struct request *rq, void *data, bool reserv)
+static bool mtip_no_dev_cleanup(struct request *rq, void *data)
 {
 	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq);
 
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 166303716560..a8f81a1618f8 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -879,7 +879,7 @@ static void recv_work(struct work_struct *work)
 	kfree(args);
 }
 
-static bool nbd_clear_req(struct request *req, void *data, bool reserved)
+static bool nbd_clear_req(struct request *req, void *data)
 {
 	struct nbd_cmd *cmd = blk_mq_rq_to_pdu(req);
 
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 6058abf42ba7..7720ea270ed8 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -1282,8 +1282,7 @@ struct srp_terminate_context {
 	int scsi_result;
 };
 
-static bool srp_terminate_cmd(struct scsi_cmnd *scmnd, void *context_ptr,
-			      bool reserved)
+static bool srp_terminate_cmd(struct scsi_cmnd *scmnd, void *context_ptr)
 {
 	struct srp_terminate_context *context = context_ptr;
 	struct srp_target_port *target = context->srp_target;
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 3ab2cfd254a4..b3d63a57e1b9 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -418,7 +418,7 @@ blk_status_t nvme_host_path_error(struct request *req)
 }
 EXPORT_SYMBOL_GPL(nvme_host_path_error);
 
-bool nvme_cancel_request(struct request *req, void *data, bool reserved)
+bool nvme_cancel_request(struct request *req, void *data)
 {
 	dev_dbg_ratelimited(((struct nvme_ctrl *) data)->device,
 				"Cancelling I/O %d", req->tag);
diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
index a166c0b1cc33..4b74f2267bb3 100644
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -2456,8 +2456,7 @@ nvme_fc_nvme_ctrl_freed(struct nvme_ctrl *nctrl)
  * status. The done path will return the io request back to the block
  * layer with an error status.
  */
-static bool
-nvme_fc_terminate_exchange(struct request *req, void *data, bool reserved)
+static bool nvme_fc_terminate_exchange(struct request *req, void *data)
 {
 	struct nvme_ctrl *nctrl = data;
 	struct nvme_fc_ctrl *ctrl = to_fc_ctrl(nctrl);
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 0da94b233fed..e4daa57f8bd5 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -697,7 +697,7 @@ static __always_inline void nvme_complete_batch(struct io_comp_batch *iob,
 }
 
 blk_status_t nvme_host_path_error(struct request *req);
-bool nvme_cancel_request(struct request *req, void *data, bool reserved);
+bool nvme_cancel_request(struct request *req, void *data);
 void nvme_cancel_tagset(struct nvme_ctrl *ctrl);
 void nvme_cancel_admin_tagset(struct nvme_ctrl *ctrl);
 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
diff --git a/drivers/scsi/aacraid/comminit.c b/drivers/scsi/aacraid/comminit.c
index 940a6deab38f..bd99c5492b7d 100644
--- a/drivers/scsi/aacraid/comminit.c
+++ b/drivers/scsi/aacraid/comminit.c
@@ -272,7 +272,7 @@ static void aac_queue_init(struct aac_dev * dev, struct aac_queue * q, u32 *mem,
 	q->entries = qsize;
 }
 
-static bool wait_for_io_iter(struct scsi_cmnd *cmd, void *data, bool rsvd)
+static bool wait_for_io_iter(struct scsi_cmnd *cmd, void *data)
 {
 	int *active = data;
 
diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
index 9c27bc37e5de..5ba5c18b77b4 100644
--- a/drivers/scsi/aacraid/linit.c
+++ b/drivers/scsi/aacraid/linit.c
@@ -633,7 +633,7 @@ struct fib_count_data {
 	int krlcnt;
 };
 
-static bool fib_count_iter(struct scsi_cmnd *scmnd, void *data, bool reserved)
+static bool fib_count_iter(struct scsi_cmnd *scmnd, void *data)
 {
 	struct fib_count_data *fib_count = data;
 
diff --git a/drivers/scsi/fnic/fnic_scsi.c b/drivers/scsi/fnic/fnic_scsi.c
index e7b7f6d73429..77a4d9f8aa83 100644
--- a/drivers/scsi/fnic/fnic_scsi.c
+++ b/drivers/scsi/fnic/fnic_scsi.c
@@ -1350,8 +1350,7 @@ int fnic_wq_copy_cmpl_handler(struct fnic *fnic, int copy_work_to_do)
 	return wq_work_done;
 }
 
-static bool fnic_cleanup_io_iter(struct scsi_cmnd *sc, void *data,
-				 bool reserved)
+static bool fnic_cleanup_io_iter(struct scsi_cmnd *sc, void *data)
 {
 	const int tag = scsi_cmd_to_rq(sc)->tag;
 	struct fnic *fnic = data;
@@ -1548,8 +1547,7 @@ struct fnic_rport_abort_io_iter_data {
 	int term_cnt;
 };
 
-static bool fnic_rport_abort_io_iter(struct scsi_cmnd *sc, void *data,
-				     bool reserved)
+static bool fnic_rport_abort_io_iter(struct scsi_cmnd *sc, void *data)
 {
 	struct fnic_rport_abort_io_iter_data *iter_data = data;
 	struct fnic *fnic = iter_data->fnic;
@@ -2003,8 +2001,7 @@ struct fnic_pending_aborts_iter_data {
 	int ret;
 };
 
-static bool fnic_pending_aborts_iter(struct scsi_cmnd *sc,
-				     void *data, bool reserved)
+static bool fnic_pending_aborts_iter(struct scsi_cmnd *sc, void *data)
 {
 	struct fnic_pending_aborts_iter_data *iter_data = data;
 	struct fnic *fnic = iter_data->fnic;
@@ -2668,8 +2665,7 @@ void fnic_exch_mgr_reset(struct fc_lport *lp, u32 sid, u32 did)
 
 }
 
-static bool fnic_abts_pending_iter(struct scsi_cmnd *sc, void *data,
-				   bool reserved)
+static bool fnic_abts_pending_iter(struct scsi_cmnd *sc, void *data)
 {
 	struct fnic_pending_aborts_iter_data *iter_data = data;
 	struct fnic *fnic = iter_data->fnic;
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 8352f90d997d..315c7ac730e9 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -566,8 +566,7 @@ struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost)
 }
 EXPORT_SYMBOL(scsi_host_get);
 
-static bool scsi_host_check_in_flight(struct request *rq, void *data,
-				      bool reserved)
+static bool scsi_host_check_in_flight(struct request *rq, void *data)
 {
 	int *count = data;
 	struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
@@ -662,7 +661,7 @@ void scsi_flush_work(struct Scsi_Host *shost)
 }
 EXPORT_SYMBOL_GPL(scsi_flush_work);
 
-static bool complete_all_cmds_iter(struct request *rq, void *data, bool rsvd)
+static bool complete_all_cmds_iter(struct request *rq, void *data)
 {
 	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
 	enum scsi_host_status status = *(enum scsi_host_status *)data;
@@ -693,17 +692,16 @@ void scsi_host_complete_all_commands(struct Scsi_Host *shost,
 EXPORT_SYMBOL_GPL(scsi_host_complete_all_commands);
 
 struct scsi_host_busy_iter_data {
-	bool (*fn)(struct scsi_cmnd *, void *, bool);
+	bool (*fn)(struct scsi_cmnd *, void *);
 	void *priv;
 };
 
-static bool __scsi_host_busy_iter_fn(struct request *req, void *priv,
-				   bool reserved)
+static bool __scsi_host_busy_iter_fn(struct request *req, void *priv)
 {
 	struct scsi_host_busy_iter_data *iter_data = priv;
 	struct scsi_cmnd *sc = blk_mq_rq_to_pdu(req);
 
-	return iter_data->fn(sc, iter_data->priv, reserved);
+	return iter_data->fn(sc, iter_data->priv);
 }
 
 /**
@@ -716,7 +714,7 @@ static bool __scsi_host_busy_iter_fn(struct request *req, void *priv,
  * ithas to be provided by the caller
  **/
 void scsi_host_busy_iter(struct Scsi_Host *shost,
-			 bool (*fn)(struct scsi_cmnd *, void *, bool),
+			 bool (*fn)(struct scsi_cmnd *, void *),
 			 void *priv)
 {
 	struct scsi_host_busy_iter_data iter_data = {
diff --git a/drivers/scsi/mpi3mr/mpi3mr_os.c b/drivers/scsi/mpi3mr/mpi3mr_os.c
index d8c195b7ca57..59a18769a4fe 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_os.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_os.c
@@ -381,14 +381,12 @@ void mpi3mr_invalidate_devhandles(struct mpi3mr_ioc *mrioc)
  * mpi3mr_print_scmd - print individual SCSI command
  * @rq: Block request
  * @data: Adapter instance reference
- * @reserved: N/A. Currently not used
  *
  * Print the SCSI command details if it is in LLD scope.
  *
  * Return: true always.
  */
-static bool mpi3mr_print_scmd(struct request *rq,
-	void *data, bool reserved)
+static bool mpi3mr_print_scmd(struct request *rq, void *data)
 {
 	struct mpi3mr_ioc *mrioc = (struct mpi3mr_ioc *)data;
 	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
@@ -412,7 +410,6 @@ static bool mpi3mr_print_scmd(struct request *rq,
  * mpi3mr_flush_scmd - Flush individual SCSI command
  * @rq: Block request
  * @data: Adapter instance reference
- * @reserved: N/A. Currently not used
  *
  * Return the SCSI command to the upper layers if it is in LLD
  * scope.
@@ -420,8 +417,7 @@ static bool mpi3mr_print_scmd(struct request *rq,
  * Return: true always.
  */
 
-static bool mpi3mr_flush_scmd(struct request *rq,
-	void *data, bool reserved)
+static bool mpi3mr_flush_scmd(struct request *rq, void *data)
 {
 	struct mpi3mr_ioc *mrioc = (struct mpi3mr_ioc *)data;
 	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
@@ -451,7 +447,6 @@ static bool mpi3mr_flush_scmd(struct request *rq,
  * mpi3mr_count_dev_pending - Count commands pending for a lun
  * @rq: Block request
  * @data: SCSI device reference
- * @reserved: Unused
  *
  * This is an iterator function called for each SCSI command in
  * a host and if the command is pending in the LLD for the
@@ -461,8 +456,7 @@ static bool mpi3mr_flush_scmd(struct request *rq,
  * Return: true always.
  */
 
-static bool mpi3mr_count_dev_pending(struct request *rq,
-	void *data, bool reserved)
+static bool mpi3mr_count_dev_pending(struct request *rq, void *data)
 {
 	struct scsi_device *sdev = (struct scsi_device *)data;
 	struct mpi3mr_sdev_priv_data *sdev_priv_data = sdev->hostdata;
@@ -485,7 +479,6 @@ static bool mpi3mr_count_dev_pending(struct request *rq,
  * mpi3mr_count_tgt_pending - Count commands pending for target
  * @rq: Block request
  * @data: SCSI target reference
- * @reserved: Unused
  *
  * This is an iterator function called for each SCSI command in
  * a host and if the command is pending in the LLD for the
@@ -495,8 +488,7 @@ static bool mpi3mr_count_dev_pending(struct request *rq,
  * Return: true always.
  */
 
-static bool mpi3mr_count_tgt_pending(struct request *rq,
-	void *data, bool reserved)
+static bool mpi3mr_count_tgt_pending(struct request *rq, void *data)
 {
 	struct scsi_target *starget = (struct scsi_target *)data;
 	struct mpi3mr_stgt_priv_data *stgt_priv_data = starget->hostdata;
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index fbb08bdd4618..811f77e32b7f 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -520,7 +520,7 @@ struct blk_mq_queue_data {
 	bool last;
 };
 
-typedef bool (busy_tag_iter_fn)(struct request *, void *, bool);
+typedef bool (busy_tag_iter_fn)(struct request *, void *);
 
 /**
  * struct blk_mq_ops - Callback functions that implements block driver
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index 667d889b92b5..65082ecdd557 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -786,7 +786,7 @@ extern int scsi_host_block(struct Scsi_Host *shost);
 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state);
 
 void scsi_host_busy_iter(struct Scsi_Host *,
-			 bool (*fn)(struct scsi_cmnd *, void *, bool), void *priv);
+			 bool (*fn)(struct scsi_cmnd *, void *), void *priv);
 
 struct class_container;
 
-- 
2.25.1

[PATCH v2 6/6] blk-mq: Drop local variable for reserved tag

[John Garry]

The local variable is now only referenced once so drop it.

Signed-off-by: John Garry <john.garry@huawei.com>
---
 block/blk-mq-tag.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 509c35f080a9..b8cc8b41553f 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -266,7 +266,6 @@ static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
 	struct blk_mq_hw_ctx *hctx = iter_data->hctx;
 	struct request_queue *q = iter_data->q;
 	struct blk_mq_tag_set *set = q->tag_set;
-	bool reserved = iter_data->reserved;
 	struct blk_mq_tags *tags;
 	struct request *rq;
 	bool ret = true;
@@ -276,7 +275,7 @@ static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
 	else
 		tags = hctx->tags;
 
-	if (!reserved)
+	if (!iter_data->reserved)
 		bitnr += tags->nr_reserved_tags;
 	/*
 	 * We can hit rq == NULL here, because the tagging functions
@@ -337,12 +336,11 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
 {
 	struct bt_tags_iter_data *iter_data = data;
 	struct blk_mq_tags *tags = iter_data->tags;
-	bool reserved = iter_data->flags & BT_TAG_ITER_RESERVED;
 	struct request *rq;
 	bool ret = true;
 	bool iter_static_rqs = !!(iter_data->flags & BT_TAG_ITER_STATIC_RQS);
 
-	if (!reserved)
+	if (!(iter_data->flags & BT_TAG_ITER_RESERVED))
 		bitnr += tags->nr_reserved_tags;
 
 	/*
-- 
2.25.1

Re: [PATCH v2 0/6] blk-mq: Add a flag for reserved requests series

[Martin K. Petersen]

John,

> In [0] I included "blk-mq: Add a flag for reserved requests" to
> identify if a request is 'reserved' for special handling. Doing this
> is easier than passing a 'reserved' arg to the blk_mq_ops
> callbacks. Indeed, only 1x timeout implementation or blk-mq iter
> function actually uses the 'reserved' arg (or 3x if you count SCSI
> core and FNIC SCSI driver). So this series drops the 'reserved' arg
> for these timeout and iter functions.  Christoph suggested that I try
> to upstream now.

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH v2 3/6] blk-mq: Drop blk_mq_ops.timeout 'reserved' arg

[Ulf Hansson]

On Tue, 21 Jun 2022 at 13:22, John Garry <john.garry@huawei.com> wrote:
>
> With new API blk_mq_is_reserved_rq() we can tell if a request is from
> the reserved pool, so stop passing 'reserved' arg. There is actually
> only a single user of that arg for all the callback implementations, which
> can use blk_mq_is_reserved_rq() instead.
>
> This will also allow us to stop passing the same 'reserved' around the
> blk-mq iter functions next.
>
> Signed-off-by: John Garry <john.garry@huawei.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Bart Van Assche <bvanassche@acm.org>
> Reviewed-by: Hannes Reinecke <hare@suse.de>

Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC

Kind regards
Uffe


> ---
>  block/blk-mq.c                    | 6 +++---
>  block/bsg-lib.c                   | 2 +-
>  drivers/block/mtip32xx/mtip32xx.c | 5 ++---
>  drivers/block/nbd.c               | 3 +--
>  drivers/block/null_blk/main.c     | 2 +-
>  drivers/mmc/core/queue.c          | 3 +--
>  drivers/nvme/host/apple.c         | 3 +--
>  drivers/nvme/host/fc.c            | 3 +--
>  drivers/nvme/host/pci.c           | 2 +-
>  drivers/nvme/host/rdma.c          | 3 +--
>  drivers/nvme/host/tcp.c           | 3 +--
>  drivers/s390/block/dasd.c         | 2 +-
>  drivers/s390/block/dasd_int.h     | 2 +-
>  drivers/scsi/scsi_error.c         | 3 +--
>  drivers/scsi/scsi_priv.h          | 3 +--
>  include/linux/blk-mq.h            | 2 +-
>  16 files changed, 19 insertions(+), 28 deletions(-)
>
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index d38c97fe89f5..81bd39e36e49 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -1426,13 +1426,13 @@ bool blk_mq_queue_inflight(struct request_queue *q)
>  }
>  EXPORT_SYMBOL_GPL(blk_mq_queue_inflight);
>
> -static void blk_mq_rq_timed_out(struct request *req, bool reserved)
> +static void blk_mq_rq_timed_out(struct request *req)
>  {
>         req->rq_flags |= RQF_TIMED_OUT;
>         if (req->q->mq_ops->timeout) {
>                 enum blk_eh_timer_return ret;
>
> -               ret = req->q->mq_ops->timeout(req, reserved);
> +               ret = req->q->mq_ops->timeout(req);
>                 if (ret == BLK_EH_DONE)
>                         return;
>                 WARN_ON_ONCE(ret != BLK_EH_RESET_TIMER);
> @@ -1481,7 +1481,7 @@ static bool blk_mq_check_expired(struct request *rq, void *priv, bool reserved)
>          * from blk_mq_check_expired().
>          */
>         if (blk_mq_req_expired(rq, next))
> -               blk_mq_rq_timed_out(rq, reserved);
> +               blk_mq_rq_timed_out(rq);
>         return true;
>  }
>
> diff --git a/block/bsg-lib.c b/block/bsg-lib.c
> index acfe1357bf6c..9570c77b9fe3 100644
> --- a/block/bsg-lib.c
> +++ b/block/bsg-lib.c
> @@ -331,7 +331,7 @@ void bsg_remove_queue(struct request_queue *q)
>  }
>  EXPORT_SYMBOL_GPL(bsg_remove_queue);
>
> -static enum blk_eh_timer_return bsg_timeout(struct request *rq, bool reserved)
> +static enum blk_eh_timer_return bsg_timeout(struct request *rq)
>  {
>         struct bsg_set *bset =
>                 container_of(rq->q->tag_set, struct bsg_set, tag_set);
> diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
> index 27386a572ba4..d5767215840c 100644
> --- a/drivers/block/mtip32xx/mtip32xx.c
> +++ b/drivers/block/mtip32xx/mtip32xx.c
> @@ -3487,12 +3487,11 @@ static int mtip_init_cmd(struct blk_mq_tag_set *set, struct request *rq,
>         return 0;
>  }
>
> -static enum blk_eh_timer_return mtip_cmd_timeout(struct request *req,
> -                                                               bool reserved)
> +static enum blk_eh_timer_return mtip_cmd_timeout(struct request *req)
>  {
>         struct driver_data *dd = req->q->queuedata;
>
> -       if (reserved) {
> +       if (blk_mq_is_reserved_rq(req)) {
>                 struct mtip_cmd *cmd = blk_mq_rq_to_pdu(req);
>
>                 cmd->status = BLK_STS_TIMEOUT;
> diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
> index 07f3c139a3d7..166303716560 100644
> --- a/drivers/block/nbd.c
> +++ b/drivers/block/nbd.c
> @@ -393,8 +393,7 @@ static u32 req_to_nbd_cmd_type(struct request *req)
>         }
>  }
>
> -static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
> -                                                bool reserved)
> +static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req)
>  {
>         struct nbd_cmd *cmd = blk_mq_rq_to_pdu(req);
>         struct nbd_device *nbd = cmd->nbd;
> diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
> index 6b67088f4ea7..2d815d1eba25 100644
> --- a/drivers/block/null_blk/main.c
> +++ b/drivers/block/null_blk/main.c
> @@ -1578,7 +1578,7 @@ static int null_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob)
>         return nr;
>  }
>
> -static enum blk_eh_timer_return null_timeout_rq(struct request *rq, bool res)
> +static enum blk_eh_timer_return null_timeout_rq(struct request *rq)
>  {
>         struct blk_mq_hw_ctx *hctx = rq->mq_hctx;
>         struct nullb_cmd *cmd = blk_mq_rq_to_pdu(rq);
> diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
> index fa5324ceeebe..17236340dbd2 100644
> --- a/drivers/mmc/core/queue.c
> +++ b/drivers/mmc/core/queue.c
> @@ -116,8 +116,7 @@ static enum blk_eh_timer_return mmc_cqe_timed_out(struct request *req)
>         }
>  }
>
> -static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req,
> -                                                bool reserved)
> +static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req)
>  {
>         struct request_queue *q = req->q;
>         struct mmc_queue *mq = q->queuedata;
> diff --git a/drivers/nvme/host/apple.c b/drivers/nvme/host/apple.c
> index d702d7d60235..495118ce958a 100644
> --- a/drivers/nvme/host/apple.c
> +++ b/drivers/nvme/host/apple.c
> @@ -862,8 +862,7 @@ static void apple_nvme_disable(struct apple_nvme *anv, bool shutdown)
>         }
>  }
>
> -static enum blk_eh_timer_return apple_nvme_timeout(struct request *req,
> -                                                  bool reserved)
> +static enum blk_eh_timer_return apple_nvme_timeout(struct request *req)
>  {
>         struct apple_nvme_iod *iod = blk_mq_rq_to_pdu(req);
>         struct apple_nvme_queue *q = iod->q;
> diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
> index 3c778bb0c294..a166c0b1cc33 100644
> --- a/drivers/nvme/host/fc.c
> +++ b/drivers/nvme/host/fc.c
> @@ -2565,8 +2565,7 @@ nvme_fc_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg)
>         nvme_reset_ctrl(&ctrl->ctrl);
>  }
>
> -static enum blk_eh_timer_return
> -nvme_fc_timeout(struct request *rq, bool reserved)
> +static enum blk_eh_timer_return nvme_fc_timeout(struct request *rq)
>  {
>         struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(rq);
>         struct nvme_fc_ctrl *ctrl = op->ctrl;
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index c7012e85d035..83b1229a4e36 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -1344,7 +1344,7 @@ static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
>                  "Try \"nvme_core.default_ps_max_latency_us=0 pcie_aspm=off\" and report a bug\n");
>  }
>
> -static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
> +static enum blk_eh_timer_return nvme_timeout(struct request *req)
>  {
>         struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
>         struct nvme_queue *nvmeq = iod->nvmeq;
> diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
> index f2a5e1ea508a..d2fb8651e49d 100644
> --- a/drivers/nvme/host/rdma.c
> +++ b/drivers/nvme/host/rdma.c
> @@ -2013,8 +2013,7 @@ static void nvme_rdma_complete_timed_out(struct request *rq)
>         nvmf_complete_timed_out_request(rq);
>  }
>
> -static enum blk_eh_timer_return
> -nvme_rdma_timeout(struct request *rq, bool reserved)
> +static enum blk_eh_timer_return nvme_rdma_timeout(struct request *rq)
>  {
>         struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
>         struct nvme_rdma_queue *queue = req->queue;
> diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
> index bb67538d241b..f21f7b0140f9 100644
> --- a/drivers/nvme/host/tcp.c
> +++ b/drivers/nvme/host/tcp.c
> @@ -2321,8 +2321,7 @@ static void nvme_tcp_complete_timed_out(struct request *rq)
>         nvmf_complete_timed_out_request(rq);
>  }
>
> -static enum blk_eh_timer_return
> -nvme_tcp_timeout(struct request *rq, bool reserved)
> +static enum blk_eh_timer_return nvme_tcp_timeout(struct request *rq)
>  {
>         struct nvme_tcp_request *req = blk_mq_rq_to_pdu(rq);
>         struct nvme_ctrl *ctrl = &req->queue->ctrl->ctrl;
> diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
> index ba6d78789660..35d6f62ed515 100644
> --- a/drivers/s390/block/dasd.c
> +++ b/drivers/s390/block/dasd.c
> @@ -3145,7 +3145,7 @@ static blk_status_t do_dasd_request(struct blk_mq_hw_ctx *hctx,
>   * BLK_EH_DONE if the request is handled or terminated
>   *                   by the driver.
>   */
> -enum blk_eh_timer_return dasd_times_out(struct request *req, bool reserved)
> +enum blk_eh_timer_return dasd_times_out(struct request *req)
>  {
>         struct dasd_block *block = req->q->queuedata;
>         struct dasd_device *device;
> diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
> index 83b918b84b4a..333a399f754e 100644
> --- a/drivers/s390/block/dasd_int.h
> +++ b/drivers/s390/block/dasd_int.h
> @@ -795,7 +795,7 @@ void dasd_free_device(struct dasd_device *);
>  struct dasd_block *dasd_alloc_block(void);
>  void dasd_free_block(struct dasd_block *);
>
> -enum blk_eh_timer_return dasd_times_out(struct request *req, bool reserved);
> +enum blk_eh_timer_return dasd_times_out(struct request *req);
>
>  void dasd_enable_device(struct dasd_device *);
>  void dasd_set_target_state(struct dasd_device *, int);
> diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
> index a8b71b73a5a5..266ce414589c 100644
> --- a/drivers/scsi/scsi_error.c
> +++ b/drivers/scsi/scsi_error.c
> @@ -318,7 +318,6 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
>  /**
>   * scsi_timeout - Timeout function for normal scsi commands.
>   * @req:       request that is timing out.
> - * @reserved:  whether the request is a reserved request.
>   *
>   * Notes:
>   *     We do not need to lock this.  There is the potential for a race
> @@ -326,7 +325,7 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
>   *     normal completion function determines that the timer has already
>   *     fired, then it mustn't do anything.
>   */
> -enum blk_eh_timer_return scsi_timeout(struct request *req, bool reserved)
> +enum blk_eh_timer_return scsi_timeout(struct request *req)
>  {
>         struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
>         enum blk_eh_timer_return rtn = BLK_EH_DONE;
> diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
> index 695d0c83ffe0..6eeaa0a7f86d 100644
> --- a/drivers/scsi/scsi_priv.h
> +++ b/drivers/scsi/scsi_priv.h
> @@ -72,8 +72,7 @@ extern void scsi_exit_devinfo(void);
>
>  /* scsi_error.c */
>  extern void scmd_eh_abort_handler(struct work_struct *work);
> -extern enum blk_eh_timer_return scsi_timeout(struct request *req,
> -                                            bool reserved);
> +extern enum blk_eh_timer_return scsi_timeout(struct request *req);
>  extern int scsi_error_handler(void *host);
>  extern enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *cmd);
>  extern void scsi_eh_wakeup(struct Scsi_Host *shost);
> diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
> index 6d81fe10e850..fbb08bdd4618 100644
> --- a/include/linux/blk-mq.h
> +++ b/include/linux/blk-mq.h
> @@ -575,7 +575,7 @@ struct blk_mq_ops {
>         /**
>          * @timeout: Called on request timeout.
>          */
> -       enum blk_eh_timer_return (*timeout)(struct request *, bool);
> +       enum blk_eh_timer_return (*timeout)(struct request *);
>
>         /**
>          * @poll: Called to poll for completion of a specific tag.
> --
> 2.25.1
>

Re: [PATCH v2 6/6] blk-mq: Drop local variable for reserved tag

[Bart Van Assche]

On 6/21/22 04:15, John Garry wrote:
> The local variable is now only referenced once so drop it.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>

Re: [PATCH v2 5/6] blk-mq: Drop 'reserved' arg of busy_tag_iter_fn

[Bart Van Assche]

On 6/21/22 04:15, John Garry wrote:
> We no longer use the 'reserved' arg in busy_tag_iter_fn for any iter
> function so it may be dropped.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>

Re: [PATCH v2 5/6] blk-mq: Drop 'reserved' arg of busy_tag_iter_fn

[Sagi Grimberg]

On 6/21/22 14:15, John Garry wrote:
> We no longer use the 'reserved' arg in busy_tag_iter_fn for any iter
> function so it may be dropped.
> 
> Signed-off-by: John Garry <john.garry@huawei.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Hannes Reinecke <hare@suse.de>
> ---
>   block/blk-mq-debugfs.c              |  2 +-
>   block/blk-mq-tag.c                  |  7 +++----
>   block/blk-mq.c                      | 10 ++++------
>   drivers/block/mtip32xx/mtip32xx.c   |  6 +++---
>   drivers/block/nbd.c                 |  2 +-
>   drivers/infiniband/ulp/srp/ib_srp.c |  3 +--
>   drivers/nvme/host/core.c            |  2 +-
>   drivers/nvme/host/fc.c              |  3 +--
>   drivers/nvme/host/nvme.h            |  2 +-

for the nvme bits:
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

Re: [PATCH v2 0/6] blk-mq: Add a flag for reserved requests series

[John Garry]

On 21/06/2022 12:15, John Garry wrote:

Hi Jens,

about this series, would you be ok to pick this up for merging? Do you 
find the changes acceptable?

Thanks,
John

> In [0] I included "blk-mq: Add a flag for reserved requests" to identify
> if a request is 'reserved' for special handling. Doing this is easier than
> passing a 'reserved' arg to the blk_mq_ops callbacks. Indeed, only 1x
> timeout implementation or blk-mq iter function actually uses the
> 'reserved' arg (or 3x if you count SCSI core and FNIC SCSI driver). So
> this series drops the 'reserved' arg for these timeout and iter functions.
> Christoph suggested that I try to upstream now.
> 
> Differences to v1:
> - Use "scsi_timeout" as name for SCSI timeout function and update docs
> - Add RB tags (thanks!)
> - Split out patch to drop local variables for 'reserved', as requested by
>    Bart
> 
> Based on following:
> 6dbcddf6e76b (block/for-5.20/block) block: bfq: Fix kernel-doc headers
> 
> [0] https://lore.kernel.org/linux-scsi/1654770559-101375-1-git-send-email-john.garry@huawei.com/T/#m22aa9f89e55835edc2e650d43f7e3219a3a1a324
> 
> John Garry (6):
>    scsi: core: Remove reserved request time-out handling
>    blk-mq: Add a flag for reserved requests
>    blk-mq: Drop blk_mq_ops.timeout 'reserved' arg
>    scsi: fnic: Drop reserved request handling
>    blk-mq: Drop 'reserved' arg of busy_tag_iter_fn
>    blk-mq: Drop local variable for reserved tag
> 
>   Documentation/scsi/scsi_eh.rst          |  3 +--
>   Documentation/scsi/scsi_mid_low_api.rst |  2 +-
>   block/blk-mq-debugfs.c                  |  2 +-
>   block/blk-mq-tag.c                      | 13 +++++--------
>   block/blk-mq.c                          | 22 +++++++++++++---------
>   block/bsg-lib.c                         |  2 +-
>   drivers/block/mtip32xx/mtip32xx.c       | 11 +++++------
>   drivers/block/nbd.c                     |  5 ++---
>   drivers/block/null_blk/main.c           |  2 +-
>   drivers/infiniband/ulp/srp/ib_srp.c     |  3 +--
>   drivers/mmc/core/queue.c                |  3 +--
>   drivers/nvme/host/apple.c               |  3 +--
>   drivers/nvme/host/core.c                |  2 +-
>   drivers/nvme/host/fc.c                  |  6 ++----
>   drivers/nvme/host/nvme.h                |  2 +-
>   drivers/nvme/host/pci.c                 |  2 +-
>   drivers/nvme/host/rdma.c                |  3 +--
>   drivers/nvme/host/tcp.c                 |  3 +--
>   drivers/s390/block/dasd.c               |  2 +-
>   drivers/s390/block/dasd_int.h           |  2 +-
>   drivers/scsi/aacraid/comminit.c         |  2 +-
>   drivers/scsi/aacraid/linit.c            |  2 +-
>   drivers/scsi/fnic/fnic_scsi.c           | 14 ++++----------
>   drivers/scsi/hosts.c                    | 14 ++++++--------
>   drivers/scsi/mpi3mr/mpi3mr_os.c         | 16 ++++------------
>   drivers/scsi/scsi_error.c               |  6 +++---
>   drivers/scsi/scsi_lib.c                 |  8 --------
>   drivers/scsi/scsi_priv.h                |  2 +-
>   include/linux/blk-mq.h                  | 10 ++++++++--
>   include/scsi/scsi_host.h                |  2 +-
>   30 files changed, 71 insertions(+), 98 deletions(-)
>