xsysace: convert to blk-mq

Straight forward conversion, using an internal list to enable the
driver to pull requests at will.

Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 55 insertions, 25 deletions

diff --git a/drivers/block/xsysace.c b/drivers/block/xsysace.c
index c24589414c75..87ccef4bd69e 100644
--- a/drivers/block/xsysace.c
+++ b/drivers/block/xsysace.c
@@ -88,7 +88,7 @@
 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/mutex.h>
 #include <linux/ata.h>
 #include <linux/hdreg.h>
@@ -209,6 +209,8 @@ struct ace_device {
         struct device *dev;
         struct request_queue *queue;
         struct gendisk *gd;
+        struct blk_mq_tag_set tag_set;
+        struct list_head rq_list;
 
         /* Inserted CF card parameters */
         u16 cf_id[ATA_ID_WORDS];
@@ -462,18 +464,26 @@ static inline void ace_fsm_yieldirq(struct ace_device *ace)
         ace->fsm_continue_flag = 0;
 }
 
+static bool ace_has_next_request(struct request_queue *q)
+{
+        struct ace_device *ace = q->queuedata;
+
+        return !list_empty(&ace->rq_list);
+}
+
 /* Get the next read/write request; ending requests that we don't handle */
 static struct request *ace_get_next_request(struct request_queue *q)
 {
-        struct request *req;
+        struct ace_device *ace = q->queuedata;
+        struct request *rq;
 
-        while ((req = blk_peek_request(q)) != NULL) {
-                if (!blk_rq_is_passthrough(req))
-                        break;
-                blk_start_request(req);
-                __blk_end_request_all(req, BLK_STS_IOERR);
+        rq = list_first_entry_or_null(&ace->rq_list, struct request, queuelist);
+        if (rq) {
+                list_del_init(&rq->queuelist);
+                blk_mq_start_request(rq);
         }
-        return req;
+
+        return NULL;
 }
 
 static void ace_fsm_dostate(struct ace_device *ace)
@@ -499,11 +509,11 @@ static void ace_fsm_dostate(struct ace_device *ace)
 
                 /* Drop all in-flight and pending requests */
                 if (ace->req) {
-                        __blk_end_request_all(ace->req, BLK_STS_IOERR);
+                        blk_mq_end_request(ace->req, BLK_STS_IOERR);
                         ace->req = NULL;
                 }
-                while ((req = blk_fetch_request(ace->queue)) != NULL)
-                        __blk_end_request_all(req, BLK_STS_IOERR);
+                while ((req = ace_get_next_request(ace->queue)) != NULL)
+                        blk_mq_end_request(req, BLK_STS_IOERR);
 
                 /* Drop back to IDLE state and notify waiters */
                 ace->fsm_state = ACE_FSM_STATE_IDLE;
@@ -517,7 +527,7 @@ static void ace_fsm_dostate(struct ace_device *ace)
         switch (ace->fsm_state) {
         case ACE_FSM_STATE_IDLE:
                 /* See if there is anything to do */
-                if (ace->id_req_count || ace_get_next_request(ace->queue)) {
+                if (ace->id_req_count || ace_has_next_request(ace->queue)) {
                         ace->fsm_iter_num++;
                         ace->fsm_state = ACE_FSM_STATE_REQ_LOCK;
                         mod_timer(&ace->stall_timer, jiffies + HZ);
@@ -651,7 +661,6 @@ static void ace_fsm_dostate(struct ace_device *ace)
                         ace->fsm_state = ACE_FSM_STATE_IDLE;
                         break;
                 }
-                blk_start_request(req);
 
                 /* Okay, it's a data request, set it up for transfer */
                 dev_dbg(ace->dev,
@@ -728,7 +737,8 @@ static void ace_fsm_dostate(struct ace_device *ace)
                 }
 
                 /* bio finished; is there another one? */
-                if (__blk_end_request_cur(ace->req, BLK_STS_OK)) {
+                if (blk_update_request(ace->req, BLK_STS_OK,
+                    blk_rq_cur_bytes(ace->req))) {
                         /* dev_dbg(ace->dev, "next block; h=%u c=%u\n",
                          *      blk_rq_sectors(ace->req),
                          *      blk_rq_cur_sectors(ace->req));
@@ -854,17 +864,23 @@ static irqreturn_t ace_interrupt(int irq, void *dev_id)
 /* ---------------------------------------------------------------------
  * Block ops
  */
-static void ace_request(struct request_queue * q)
+static blk_status_t ace_queue_rq(struct blk_mq_hw_ctx *hctx,
+                                 const struct blk_mq_queue_data *bd)
 {
-        struct request *req;
-        struct ace_device *ace;
-
-        req = ace_get_next_request(q);
+        struct ace_device *ace = hctx->queue->queuedata;
+        struct request *req = bd->rq;
 
-        if (req) {
-                ace = req->rq_disk->private_data;
-                tasklet_schedule(&ace->fsm_tasklet);
+        if (blk_rq_is_passthrough(req)) {
+                blk_mq_start_request(req);
+                return BLK_STS_IOERR;
         }
+
+        spin_lock_irq(&ace->lock);
+        list_add_tail(&req->queuelist, &ace->rq_list);
+        spin_unlock_irq(&ace->lock);
+
+        tasklet_schedule(&ace->fsm_tasklet);
+        return BLK_STS_OK;
 }
 
 static unsigned int ace_check_events(struct gendisk *gd, unsigned int clearing)
@@ -957,6 +973,10 @@ static const struct block_device_operations ace_fops = {
         .getgeo = ace_getgeo,
 };
 
+static const struct blk_mq_ops ace_mq_ops = {
+        .queue_rq       = ace_queue_rq,
+};
+
 /* --------------------------------------------------------------------
  * SystemACE device setup/teardown code
  */
@@ -972,6 +992,7 @@ static int ace_setup(struct ace_device *ace)
 
         spin_lock_init(&ace->lock);
         init_completion(&ace->id_completion);
+        INIT_LIST_HEAD(&ace->rq_list);
 
         /*
          * Map the device
@@ -989,9 +1010,15 @@ static int ace_setup(struct ace_device *ace)
         /*
          * Initialize the request queue
          */
-        ace->queue = blk_init_queue(ace_request, &ace->lock);
-        if (ace->queue == NULL)
+        ace->queue = blk_mq_init_sq_queue(&ace->tag_set, &ace_mq_ops, 2,
+                                                BLK_MQ_F_SHOULD_MERGE);
+        if (IS_ERR(ace->queue)) {
+                rc = PTR_ERR(ace->queue);
+                ace->queue = NULL;
                 goto err_blk_initq;
+        }
+        ace->queue->queuedata = ace;
+
         blk_queue_logical_block_size(ace->queue, 512);
         blk_queue_bounce_limit(ace->queue, BLK_BOUNCE_HIGH);
 
@@ -1066,6 +1093,7 @@ err_read:
         put_disk(ace->gd);
 err_alloc_disk:
         blk_cleanup_queue(ace->queue);
+        blk_mq_free_tag_set(&ace->tag_set);
 err_blk_initq:
         iounmap(ace->baseaddr);
 err_ioremap:
@@ -1081,8 +1109,10 @@ static void ace_teardown(struct ace_device *ace)
                 put_disk(ace->gd);
         }
 
-        if (ace->queue)
+        if (ace->queue) {
                 blk_cleanup_queue(ace->queue);
+                blk_mq_free_tag_set(&ace->tag_set);
+        }
 
         tasklet_kill(&ace->fsm_tasklet);