diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 7a8a73f1fc04..5dd591d6c859 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -37,6 +37,7 @@ #include #include +#include #include #include #include @@ -148,6 +149,7 @@ struct blkfront_info unsigned int feature_persistent:1; unsigned int max_indirect_segments; int is_ready; + struct blk_mq_tag_set tag_set; }; static unsigned int nr_minors; @@ -617,54 +619,41 @@ static inline bool blkif_request_flush_invalid(struct request *req, !(info->feature_flush & REQ_FUA))); } -/* - * do_blkif_request - * read a block; request is in a request queue - */ -static void do_blkif_request(struct request_queue *rq) +static int blkif_queue_rq(struct blk_mq_hw_ctx *hctx, + const struct blk_mq_queue_data *qd) { - struct blkfront_info *info = NULL; - struct request *req; - int queued; + struct blkfront_info *info = qd->rq->rq_disk->private_data; - pr_debug("Entered do_blkif_request\n"); + blk_mq_start_request(qd->rq); + spin_lock_irq(&info->io_lock); + if (RING_FULL(&info->ring)) + goto out_busy; - queued = 0; + if (blkif_request_flush_invalid(qd->rq, info)) + goto out_err; - while ((req = blk_peek_request(rq)) != NULL) { - info = req->rq_disk->private_data; + if (blkif_queue_request(qd->rq)) + goto out_busy; - if (RING_FULL(&info->ring)) - goto wait; + flush_requests(info); + spin_unlock_irq(&info->io_lock); + return BLK_MQ_RQ_QUEUE_OK; - blk_start_request(req); +out_err: + spin_unlock_irq(&info->io_lock); + return BLK_MQ_RQ_QUEUE_ERROR; - if (blkif_request_flush_invalid(req, info)) { - __blk_end_request_all(req, -EOPNOTSUPP); - continue; - } - - pr_debug("do_blk_req %p: cmd %p, sec %lx, " - "(%u/%u) [%s]\n", - req, req->cmd, (unsigned long)blk_rq_pos(req), - blk_rq_cur_sectors(req), blk_rq_sectors(req), - rq_data_dir(req) ? "write" : "read"); - - if (blkif_queue_request(req)) { - blk_requeue_request(rq, req); -wait: - /* Avoid pointless unplugs. */ - blk_stop_queue(rq); - break; - } - - queued++; - } - - if (queued != 0) - flush_requests(info); +out_busy: + spin_unlock_irq(&info->io_lock); + blk_mq_stop_hw_queue(hctx); + return BLK_MQ_RQ_QUEUE_BUSY; } +static struct blk_mq_ops blkfront_mq_ops = { + .queue_rq = blkif_queue_rq, + .map_queue = blk_mq_map_queue, +}; + static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size, unsigned int physical_sector_size, unsigned int segments) @@ -672,9 +661,22 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size, struct request_queue *rq; struct blkfront_info *info = gd->private_data; - rq = blk_init_queue(do_blkif_request, &info->io_lock); - if (rq == NULL) + memset(&info->tag_set, 0, sizeof(info->tag_set)); + info->tag_set.ops = &blkfront_mq_ops; + info->tag_set.nr_hw_queues = 1; + info->tag_set.queue_depth = BLK_RING_SIZE(info); + info->tag_set.numa_node = NUMA_NO_NODE; + info->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE; + info->tag_set.cmd_size = 0; + info->tag_set.driver_data = info; + + if (blk_mq_alloc_tag_set(&info->tag_set)) return -1; + rq = blk_mq_init_queue(&info->tag_set); + if (IS_ERR(rq)) { + blk_mq_free_tag_set(&info->tag_set); + return -1; + } queue_flag_set_unlocked(QUEUE_FLAG_VIRT, rq); @@ -902,19 +904,15 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity, static void xlvbd_release_gendisk(struct blkfront_info *info) { unsigned int minor, nr_minors; - unsigned long flags; if (info->rq == NULL) return; - spin_lock_irqsave(&info->io_lock, flags); - /* No more blkif_request(). */ - blk_stop_queue(info->rq); + blk_mq_stop_hw_queues(info->rq); /* No more gnttab callback work. */ gnttab_cancel_free_callback(&info->callback); - spin_unlock_irqrestore(&info->io_lock, flags); /* Flush gnttab callback work. Must be done with no locks held. */ flush_work(&info->work); @@ -926,20 +924,18 @@ static void xlvbd_release_gendisk(struct blkfront_info *info) xlbd_release_minors(minor, nr_minors); blk_cleanup_queue(info->rq); + blk_mq_free_tag_set(&info->tag_set); info->rq = NULL; put_disk(info->gd); info->gd = NULL; } +/* Must be called with io_lock holded */ static void kick_pending_request_queues(struct blkfront_info *info) { - if (!RING_FULL(&info->ring)) { - /* Re-enable calldowns. */ - blk_start_queue(info->rq); - /* Kick things off immediately. */ - do_blkif_request(info->rq); - } + if (!RING_FULL(&info->ring)) + blk_mq_start_stopped_hw_queues(info->rq, true); } static void blkif_restart_queue(struct work_struct *work) @@ -964,7 +960,7 @@ static void blkif_free(struct blkfront_info *info, int suspend) BLKIF_STATE_SUSPENDED : BLKIF_STATE_DISCONNECTED; /* No more blkif_request(). */ if (info->rq) - blk_stop_queue(info->rq); + blk_mq_stop_hw_queues(info->rq); /* Remove all persistent grants */ if (!list_empty(&info->grants)) { @@ -1147,7 +1143,6 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id) RING_IDX i, rp; unsigned long flags; struct blkfront_info *info = (struct blkfront_info *)dev_id; - int error; spin_lock_irqsave(&info->io_lock, flags); @@ -1188,37 +1183,37 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id) continue; } - error = (bret->status == BLKIF_RSP_OKAY) ? 0 : -EIO; + req->errors = (bret->status == BLKIF_RSP_OKAY) ? 0 : -EIO; switch (bret->operation) { case BLKIF_OP_DISCARD: if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) { struct request_queue *rq = info->rq; printk(KERN_WARNING "blkfront: %s: %s op failed\n", info->gd->disk_name, op_name(bret->operation)); - error = -EOPNOTSUPP; + req->errors = -EOPNOTSUPP; info->feature_discard = 0; info->feature_secdiscard = 0; queue_flag_clear(QUEUE_FLAG_DISCARD, rq); queue_flag_clear(QUEUE_FLAG_SECDISCARD, rq); } - __blk_end_request_all(req, error); + blk_mq_complete_request(req); break; case BLKIF_OP_FLUSH_DISKCACHE: case BLKIF_OP_WRITE_BARRIER: if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) { printk(KERN_WARNING "blkfront: %s: %s op failed\n", info->gd->disk_name, op_name(bret->operation)); - error = -EOPNOTSUPP; + req->errors = -EOPNOTSUPP; } if (unlikely(bret->status == BLKIF_RSP_ERROR && info->shadow[id].req.u.rw.nr_segments == 0)) { printk(KERN_WARNING "blkfront: %s: empty %s op failed\n", info->gd->disk_name, op_name(bret->operation)); - error = -EOPNOTSUPP; + req->errors = -EOPNOTSUPP; } - if (unlikely(error)) { - if (error == -EOPNOTSUPP) - error = 0; + if (unlikely(req->errors)) { + if (req->errors == -EOPNOTSUPP) + req->errors = 0; info->feature_flush = 0; xlvbd_flush(info); } @@ -1229,7 +1224,7 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id) dev_dbg(&info->xbdev->dev, "Bad return from blkdev data " "request: %x\n", bret->status); - __blk_end_request_all(req, error); + blk_mq_complete_request(req); break; default: BUG(); @@ -1558,28 +1553,6 @@ static int blkif_recover(struct blkfront_info *info) kfree(copy); - /* - * Empty the queue, this is important because we might have - * requests in the queue with more segments than what we - * can handle now. - */ - spin_lock_irq(&info->io_lock); - while ((req = blk_fetch_request(info->rq)) != NULL) { - if (req->cmd_flags & - (REQ_FLUSH | REQ_FUA | REQ_DISCARD | REQ_SECURE)) { - list_add(&req->queuelist, &requests); - continue; - } - merge_bio.head = req->bio; - merge_bio.tail = req->biotail; - bio_list_merge(&bio_list, &merge_bio); - req->bio = NULL; - if (req->cmd_flags & (REQ_FLUSH | REQ_FUA)) - pr_alert("diskcache flush request found!\n"); - __blk_end_request_all(req, 0); - } - spin_unlock_irq(&info->io_lock); - xenbus_switch_state(info->xbdev, XenbusStateConnected); spin_lock_irq(&info->io_lock); @@ -1594,9 +1567,10 @@ static int blkif_recover(struct blkfront_info *info) /* Requeue pending requests (flush or discard) */ list_del_init(&req->queuelist); BUG_ON(req->nr_phys_segments > segs); - blk_requeue_request(info->rq, req); + blk_mq_requeue_request(req); } spin_unlock_irq(&info->io_lock); + blk_mq_kick_requeue_list(info->rq); while ((bio = bio_list_pop(&bio_list)) != NULL) { /* Traverse the list of pending bios and re-queue them */