scsi: block: Introduce BLK_MQ_REQ_PM

Introduce the BLK_MQ_REQ_PM flag. This flag makes the request allocation
functions set RQF_PM. This is the first step towards removing
BLK_MQ_REQ_PREEMPT.

Link: https://lore.kernel.org/r/20201209052951.16136-3-bvanassche@acm.org
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Can Guo <cang@codeaurora.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/block/blk-core.c b/block/blk-core.c
index 2db8bda..10696f9 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -424,11 +424,11 @@ EXPORT_SYMBOL(blk_cleanup_queue);
 /**
  * blk_queue_enter() - try to increase q->q_usage_counter
  * @q: request queue pointer
- * @flags: BLK_MQ_REQ_NOWAIT and/or BLK_MQ_REQ_PREEMPT
+ * @flags: BLK_MQ_REQ_NOWAIT, BLK_MQ_REQ_PM and/or BLK_MQ_REQ_PREEMPT
  */
 int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
 {
-       const bool pm = flags & BLK_MQ_REQ_PREEMPT;
+       const bool pm = flags & (BLK_MQ_REQ_PM | BLK_MQ_REQ_PREEMPT);
 
        while (true) {
                bool success = false;
@@ -630,7 +630,8 @@ struct request *blk_get_request(struct request_queue *q, unsigned int op,
        struct request *req;
 
        WARN_ON_ONCE(op & REQ_NOWAIT);
-       WARN_ON_ONCE(flags & ~(BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_PREEMPT));
+       WARN_ON_ONCE(flags & ~(BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_PM |
+                              BLK_MQ_REQ_PREEMPT));
 
        req = blk_mq_alloc_request(q, op, flags);
        if (!IS_ERR(req) && q->mq_ops->initialize_rq_fn)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 1b25ec2..b5880a1 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -292,6 +292,8 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
        rq->mq_hctx = data->hctx;
        rq->rq_flags = 0;
        rq->cmd_flags = data->cmd_flags;
+       if (data->flags & BLK_MQ_REQ_PM)
+               rq->rq_flags |= RQF_PM;
        if (data->flags & BLK_MQ_REQ_PREEMPT)
                rq->rq_flags |= RQF_PREEMPT;
        if (blk_queue_io_stat(data->q))

diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index b23eeca..c00e856 100644 (file)
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -444,6 +444,8 @@ enum {
        BLK_MQ_REQ_NOWAIT       = (__force blk_mq_req_flags_t)(1 << 0),
        /* allocate from reserved pool */
        BLK_MQ_REQ_RESERVED     = (__force blk_mq_req_flags_t)(1 << 1),
+       /* set RQF_PM */
+       BLK_MQ_REQ_PM           = (__force blk_mq_req_flags_t)(1 << 2),
        /* set RQF_PREEMPT */
        BLK_MQ_REQ_PREEMPT      = (__force blk_mq_req_flags_t)(1 << 3),
 };