paride: convert pcd to blk-mq

Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c
index a026211..96670ee 100644 (file)
--- a/drivers/block/paride/pcd.c
+++ b/drivers/block/paride/pcd.c
@@ -137,7 +137,7 @@ enum {D_PRT, D_PRO, D_UNI, D_MOD, D_SLV, D_DLY};
 #include <linux/delay.h>
 #include <linux/cdrom.h>
 #include <linux/spinlock.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/mutex.h>
 #include <linux/uaccess.h>
 
@@ -186,7 +186,8 @@ static int pcd_packet(struct cdrom_device_info *cdi,
 static int pcd_detect(void);
 static void pcd_probe_capabilities(void);
 static void do_pcd_read_drq(void);
-static void do_pcd_request(struct request_queue * q);
+static blk_status_t pcd_queue_rq(struct blk_mq_hw_ctx *hctx,
+                                const struct blk_mq_queue_data *bd);
 static void do_pcd_read(void);
 
 struct pcd_unit {
@@ -199,6 +200,8 @@ struct pcd_unit {
        char *name;             /* pcd0, pcd1, etc */
        struct cdrom_device_info info;  /* uniform cdrom interface */
        struct gendisk *disk;
+       struct blk_mq_tag_set tag_set;
+       struct list_head rq_list;
 };
 
 static struct pcd_unit pcd[PCD_UNITS];
@@ -292,6 +295,10 @@ static const struct cdrom_device_ops pcd_dops = {
                          CDC_CD_RW,
 };
 
+static const struct blk_mq_ops pcd_mq_ops = {
+       .queue_rq       = pcd_queue_rq,
+};
+
 static void pcd_init_units(void)
 {
        struct pcd_unit *cd;
@@ -300,13 +307,19 @@ static void pcd_init_units(void)
        pcd_drive_count = 0;
        for (unit = 0, cd = pcd; unit < PCD_UNITS; unit++, cd++) {
                struct gendisk *disk = alloc_disk(1);
+
                if (!disk)
                        continue;
-               disk->queue = blk_init_queue(do_pcd_request, &pcd_lock);
-               if (!disk->queue) {
-                       put_disk(disk);
+
+               disk->queue = blk_mq_init_sq_queue(&cd->tag_set, &pcd_mq_ops,
+                                                  1, BLK_MQ_F_SHOULD_MERGE);
+               if (IS_ERR(disk->queue)) {
+                       disk->queue = NULL;
                        continue;
                }
+
+               INIT_LIST_HEAD(&cd->rq_list);
+               disk->queue->queuedata = cd;
                blk_queue_bounce_limit(disk->queue, BLK_BOUNCE_HIGH);
                cd->disk = disk;
                cd->pi = &cd->pia;
@@ -748,18 +761,18 @@ static int pcd_queue;
 static int set_next_request(void)
 {
        struct pcd_unit *cd;
-       struct request_queue *q;
        int old_pos = pcd_queue;
 
        do {
                cd = &pcd[pcd_queue];
-               q = cd->present ? cd->disk->queue : NULL;
                if (++pcd_queue == PCD_UNITS)
                        pcd_queue = 0;
-               if (q) {
-                       pcd_req = blk_fetch_request(q);
-                       if (pcd_req)
-                               break;
+               if (cd->present && !list_empty(&cd->rq_list)) {
+                       pcd_req = list_first_entry(&cd->rq_list, struct request,
+                                                       queuelist);
+                       list_del_init(&pcd_req->queuelist);
+                       blk_mq_start_request(pcd_req);
+                       break;
                }
        } while (pcd_queue != old_pos);
 
@@ -768,33 +781,41 @@ static int set_next_request(void)
 
 static void pcd_request(void)
 {
+       struct pcd_unit *cd;
+
        if (pcd_busy)
                return;
-       while (1) {
-               if (!pcd_req && !set_next_request())
-                       return;
 
-               if (rq_data_dir(pcd_req) == READ) {
-                       struct pcd_unit *cd = pcd_req->rq_disk->private_data;
-                       if (cd != pcd_current)
-                               pcd_bufblk = -1;
-                       pcd_current = cd;
-                       pcd_sector = blk_rq_pos(pcd_req);
-                       pcd_count = blk_rq_cur_sectors(pcd_req);
-                       pcd_buf = bio_data(pcd_req->bio);
-                       pcd_busy = 1;
-                       ps_set_intr(do_pcd_read, NULL, 0, nice);
-                       return;
-               } else {
-                       __blk_end_request_all(pcd_req, BLK_STS_IOERR);
-                       pcd_req = NULL;
-               }
-       }
+       if (!pcd_req && !set_next_request())
+               return;
+
+       cd = pcd_req->rq_disk->private_data;
+       if (cd != pcd_current)
+               pcd_bufblk = -1;
+       pcd_current = cd;
+       pcd_sector = blk_rq_pos(pcd_req);
+       pcd_count = blk_rq_cur_sectors(pcd_req);
+       pcd_buf = bio_data(pcd_req->bio);
+       pcd_busy = 1;
+       ps_set_intr(do_pcd_read, NULL, 0, nice);
 }
 
-static void do_pcd_request(struct request_queue *q)
+static blk_status_t pcd_queue_rq(struct blk_mq_hw_ctx *hctx,
+                                const struct blk_mq_queue_data *bd)
 {
+       struct pcd_unit *cd = hctx->queue->queuedata;
+
+       if (rq_data_dir(bd->rq) != READ) {
+               blk_mq_start_request(bd->rq);
+               return BLK_STS_IOERR;
+       }
+
+       spin_lock_irq(&pcd_lock);
+       list_add_tail(&bd->rq->queuelist, &cd->rq_list);
        pcd_request();
+       spin_unlock_irq(&pcd_lock);
+
+       return BLK_STS_OK;
 }
 
 static inline void next_request(blk_status_t err)
@@ -802,8 +823,10 @@ static inline void next_request(blk_status_t err)
        unsigned long saved_flags;
 
        spin_lock_irqsave(&pcd_lock, saved_flags);
-       if (!__blk_end_request_cur(pcd_req, err))
+       if (!blk_update_request(pcd_req, err, blk_rq_cur_bytes(pcd_req))) {
+               __blk_mq_end_request(pcd_req, err);
                pcd_req = NULL;
+       }
        pcd_busy = 0;
        pcd_request();
        spin_unlock_irqrestore(&pcd_lock, saved_flags);
@@ -1011,6 +1034,7 @@ static void __exit pcd_exit(void)
                        unregister_cdrom(&cd->info);
                }
                blk_cleanup_queue(cd->disk->queue);
+               blk_mq_free_tag_set(&cd->tag_set);
                put_disk(cd->disk);
        }
        unregister_blkdev(major, name);