ide: convert to blk-mq

ide-disk and ide-cd tested as working just fine, ide-tape and
ide-floppy haven't. But the latter don't require changes, so they
should work without issue.

Add helper function to insert a request from a work queue, since we
cannot invoke the blk-mq request insertion from IRQ context.

Cc: David Miller <davem@davemloft.net>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 17 insertions, 8 deletions

diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c
index 8b2b72b93885..33210bc67618 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -172,8 +172,8 @@ EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
 void ide_prep_sense(ide_drive_t *drive, struct request *rq)
 {
         struct request_sense *sense = &drive->sense_data;
-        struct request *sense_rq = drive->sense_rq;
-        struct scsi_request *req = scsi_req(sense_rq);
+        struct request *sense_rq;
+        struct scsi_request *req;
         unsigned int cmd_len, sense_len;
         int err;
 
@@ -196,9 +196,16 @@ void ide_prep_sense(ide_drive_t *drive, struct request *rq)
         if (ata_sense_request(rq) || drive->sense_rq_armed)
                 return;
 
+        sense_rq = drive->sense_rq;
+        if (!sense_rq) {
+                sense_rq = blk_mq_alloc_request(drive->queue, REQ_OP_DRV_IN,
+                                        BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
+                drive->sense_rq = sense_rq;
+        }
+        req = scsi_req(sense_rq);
+
         memset(sense, 0, sizeof(*sense));
 
-        blk_rq_init(rq->q, sense_rq);
         scsi_req_init(req);
 
         err = blk_rq_map_kern(drive->queue, sense_rq, sense, sense_len,
@@ -207,6 +214,8 @@ void ide_prep_sense(ide_drive_t *drive, struct request *rq)
                 if (printk_ratelimit())
                         printk(KERN_WARNING PFX "%s: failed to map sense "
                                             "buffer\n", drive->name);
+                blk_mq_free_request(sense_rq);
+                drive->sense_rq = NULL;
                 return;
         }
 
@@ -226,6 +235,8 @@ EXPORT_SYMBOL_GPL(ide_prep_sense);
 
 int ide_queue_sense_rq(ide_drive_t *drive, void *special)
 {
+        struct request *sense_rq = drive->sense_rq;
+
         /* deferred failure from ide_prep_sense() */
         if (!drive->sense_rq_armed) {
                 printk(KERN_WARNING PFX "%s: error queuing a sense request\n",
@@ -233,12 +244,12 @@ int ide_queue_sense_rq(ide_drive_t *drive, void *special)
                 return -ENOMEM;
         }
 
-        drive->sense_rq->special = special;
+        sense_rq->special = special;
         drive->sense_rq_armed = false;
 
         drive->hwif->rq = NULL;
 
-        elv_add_request(drive->queue, drive->sense_rq, ELEVATOR_INSERT_FRONT);
+        ide_insert_request_head(drive, sense_rq);
         return 0;
 }
 EXPORT_SYMBOL_GPL(ide_queue_sense_rq);
@@ -270,10 +281,8 @@ void ide_retry_pc(ide_drive_t *drive)
          */
         drive->hwif->rq = NULL;
         ide_requeue_and_plug(drive, failed_rq);
-        if (ide_queue_sense_rq(drive, pc)) {
-                blk_start_request(failed_rq);
+        if (ide_queue_sense_rq(drive, pc))
                 ide_complete_rq(drive, BLK_STS_IOERR, blk_rq_bytes(failed_rq));
-        }
 }
 EXPORT_SYMBOL_GPL(ide_retry_pc);