diff options
| -rw-r--r-- | drivers/block/virtio_blk.c | 322 |
1 files changed, 65 insertions, 257 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 5cdf88b7ad9e..7455fe24bbbe 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -11,12 +11,11 @@ #include <linux/string_helpers.h> #include <scsi/scsi_cmnd.h> #include <linux/idr.h> +#include <linux/blk-mq.h> +#include <linux/numa.h> #define PART_BITS 4 -static bool use_bio; -module_param(use_bio, bool, S_IRUGO); - static int major; static DEFINE_IDA(vd_index_ida); @@ -26,13 +25,11 @@ struct virtio_blk { struct virtio_device *vdev; struct virtqueue *vq; - wait_queue_head_t queue_wait; + spinlock_t vq_lock; /* The disk structure for the kernel. */ struct gendisk *disk; - mempool_t *pool; - /* Process context for config space updates */ struct work_struct config_work; @@ -47,31 +44,17 @@ struct virtio_blk /* Ida index - used to track minor number allocations. */ int index; - - /* Scatterlist: can be too big for stack. */ - struct scatterlist sg[/*sg_elems*/]; }; struct virtblk_req { struct request *req; - struct bio *bio; struct virtio_blk_outhdr out_hdr; struct virtio_scsi_inhdr in_hdr; - struct work_struct work; - struct virtio_blk *vblk; - int flags; u8 status; struct scatterlist sg[]; }; -enum { - VBLK_IS_FLUSH = 1, - VBLK_REQ_FLUSH = 2, - VBLK_REQ_DATA = 4, - VBLK_REQ_FUA = 8, -}; - static inline int virtblk_result(struct virtblk_req *vbr) { switch (vbr->status) { @@ -84,22 +67,6 @@ static inline int virtblk_result(struct virtblk_req *vbr) } } -static inline struct virtblk_req *virtblk_alloc_req(struct virtio_blk *vblk, - gfp_t gfp_mask) -{ - struct virtblk_req *vbr; - - vbr = mempool_alloc(vblk->pool, gfp_mask); - if (!vbr) - return NULL; - - vbr->vblk = vblk; - if (use_bio) - sg_init_table(vbr->sg, vblk->sg_elems); - - return vbr; -} - static int __virtblk_add_req(struct virtqueue *vq, struct virtblk_req *vbr, struct scatterlist *data_sg, @@ -143,83 +110,8 @@ static int __virtblk_add_req(struct virtqueue *vq, return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC); } -static void virtblk_add_req(struct virtblk_req *vbr, bool have_data) -{ - struct virtio_blk *vblk = vbr->vblk; - DEFINE_WAIT(wait); - int ret; - - spin_lock_irq(vblk->disk->queue->queue_lock); - while (unlikely((ret = __virtblk_add_req(vblk->vq, vbr, vbr->sg, - have_data)) < 0)) { - prepare_to_wait_exclusive(&vblk->queue_wait, &wait, - TASK_UNINTERRUPTIBLE); - - spin_unlock_irq(vblk->disk->queue->queue_lock); - io_schedule(); - spin_lock_irq(vblk->disk->queue->queue_lock); - - finish_wait(&vblk->queue_wait, &wait); - } - - virtqueue_kick(vblk->vq); - spin_unlock_irq(vblk->disk->queue->queue_lock); -} - -static void virtblk_bio_send_flush(struct virtblk_req *vbr) -{ - vbr->flags |= VBLK_IS_FLUSH; - vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH; - vbr->out_hdr.sector = 0; - vbr->out_hdr.ioprio = 0; - - virtblk_add_req(vbr, false); -} - -static void virtblk_bio_send_data(struct virtblk_req *vbr) -{ - struct virtio_blk *vblk = vbr->vblk; - struct bio *bio = vbr->bio; - bool have_data; - - vbr->flags &= ~VBLK_IS_FLUSH; - vbr->out_hdr.type = 0; - vbr->out_hdr.sector = bio->bi_sector; - vbr->out_hdr.ioprio = bio_prio(bio); - - if (blk_bio_map_sg(vblk->disk->queue, bio, vbr->sg)) { - have_data = true; - if (bio->bi_rw & REQ_WRITE) - vbr->out_hdr.type |= VIRTIO_BLK_T_OUT; - else - vbr->out_hdr.type |= VIRTIO_BLK_T_IN; - } else - have_data = false; - - virtblk_add_req(vbr, have_data); -} - -static void virtblk_bio_send_data_work(struct work_struct *work) -{ - struct virtblk_req *vbr; - - vbr = container_of(work, struct virtblk_req, work); - - virtblk_bio_send_data(vbr); -} - -static void virtblk_bio_send_flush_work(struct work_struct *work) -{ - struct virtblk_req *vbr; - - vbr = container_of(work, struct virtblk_req, work); - - virtblk_bio_send_flush(vbr); -} - static inline void virtblk_request_done(struct virtblk_req *vbr) { - struct virtio_blk *vblk = vbr->vblk; struct request *req = vbr->req; int error = virtblk_result(vbr); @@ -231,90 +123,43 @@ static inline void virtblk_request_done(struct virtblk_req *vbr) req->errors = (error != 0); } - __blk_end_request_all(req, error); - mempool_free(vbr, vblk->pool); -} - -static inline void virtblk_bio_flush_done(struct virtblk_req *vbr) -{ - struct virtio_blk *vblk = vbr->vblk; - - if (vbr->flags & VBLK_REQ_DATA) { - /* Send out the actual write data */ - INIT_WORK(&vbr->work, virtblk_bio_send_data_work); - queue_work(virtblk_wq, &vbr->work); - } else { - bio_endio(vbr->bio, virtblk_result(vbr)); - mempool_free(vbr, vblk->pool); - } -} - -static inline void virtblk_bio_data_done(struct virtblk_req *vbr) -{ - struct virtio_blk *vblk = vbr->vblk; - - if (unlikely(vbr->flags & VBLK_REQ_FUA)) { - /* Send out a flush before end the bio */ - vbr->flags &= ~VBLK_REQ_DATA; - INIT_WORK(&vbr->work, virtblk_bio_send_flush_work); - queue_work(virtblk_wq, &vbr->work); - } else { - bio_endio(vbr->bio, virtblk_result(vbr)); - mempool_free(vbr, vblk->pool); - } -} - -static inline void virtblk_bio_done(struct virtblk_req *vbr) -{ - if (unlikely(vbr->flags & VBLK_IS_FLUSH)) - virtblk_bio_flush_done(vbr); - else - virtblk_bio_data_done(vbr); + blk_mq_end_io(req, error); } static void virtblk_done(struct virtqueue *vq) { struct virtio_blk *vblk = vq->vdev->priv; - bool bio_done = false, req_done = false; + bool req_done = false; struct virtblk_req *vbr; unsigned long flags; unsigned int len; - spin_lock_irqsave(vblk->disk->queue->queue_lock, flags); + spin_lock_irqsave(&vblk->vq_lock, flags); do { virtqueue_disable_cb(vq); while ((vbr = virtqueue_get_buf(vblk->vq, &len)) != NULL) { - if (vbr->bio) { - virtblk_bio_done(vbr); - bio_done = true; - } else { - virtblk_request_done(vbr); - req_done = true; - } + virtblk_request_done(vbr); + req_done = true; } } while (!virtqueue_enable_cb(vq)); + spin_unlock_irqrestore(&vblk->vq_lock, flags); + /* In case queue is stopped waiting for more buffers. */ if (req_done) - blk_start_queue(vblk->disk->queue); - spin_unlock_irqrestore(vblk->disk->queue->queue_lock, flags); - - if (bio_done) - wake_up(&vblk->queue_wait); + blk_mq_start_stopped_hw_queues(vblk->disk->queue); } -static bool do_req(struct request_queue *q, struct virtio_blk *vblk, - struct request *req) +static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *req) { + struct virtio_blk *vblk = hctx->queue->queuedata; + struct virtblk_req *vbr = req->special; + unsigned long flags; unsigned int num; - struct virtblk_req *vbr; + const bool last = (req->cmd_flags & REQ_END) != 0; - vbr = virtblk_alloc_req(vblk, GFP_ATOMIC); - if (!vbr) - /* When another request finishes we'll try again. */ - return false; + BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems); vbr->req = req; - vbr->bio = NULL; if (req->cmd_flags & REQ_FLUSH) { vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH; vbr->out_hdr.sector = 0; @@ -342,7 +187,7 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk, } } - num = blk_rq_map_sg(q, vbr->req, vblk->sg); + num = blk_rq_map_sg(hctx->queue, vbr->req, vbr->sg); if (num) { if (rq_data_dir(vbr->req) == WRITE) vbr->out_hdr.type |= VIRTIO_BLK_T_OUT; @@ -350,63 +195,18 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk, vbr->out_hdr.type |= VIRTIO_BLK_T_IN; } - if (__virtblk_add_req(vblk->vq, vbr, vblk->sg, num) < 0) { - mempool_free(vbr, vblk->pool); - return false; - } - - return true; -} - -static void virtblk_request(struct request_queue *q) -{ - struct virtio_blk *vblk = q->queuedata; - struct request *req; - unsigned int issued = 0; - - while ((req = blk_peek_request(q)) != NULL) { - BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems); - - /* If this request fails, stop queue and wait for something to - finish to restart it. */ - if (!do_req(q, vblk, req)) { - blk_stop_queue(q); - break; - } - blk_start_request(req); - issued++; - } - - if (issued) + spin_lock_irqsave(&vblk->vq_lock, flags); + if (__virtblk_add_req(vblk->vq, vbr, vbr->sg, num) < 0) { + spin_unlock_irqrestore(&vblk->vq_lock, flags); + blk_mq_stop_hw_queue(hctx); virtqueue_kick(vblk->vq); -} - -static void virtblk_make_request(struct request_queue *q, struct bio *bio) -{ - struct virtio_blk *vblk = q->queuedata; - struct virtblk_req *vbr; - - BUG_ON(bio->bi_phys_segments + 2 > vblk->sg_elems); - - vbr = virtblk_alloc_req(vblk, GFP_NOIO); - if (!vbr) { - bio_endio(bio, -ENOMEM); - return; + return BLK_MQ_RQ_QUEUE_BUSY; } + spin_unlock_irqrestore(&vblk->vq_lock, flags); - vbr->bio = bio; - vbr->flags = 0; - if (bio->bi_rw & REQ_FLUSH) - vbr->flags |= VBLK_REQ_FLUSH; - if (bio->bi_rw & REQ_FUA) - vbr->flags |= VBLK_REQ_FUA; - if (bio->bi_size) - vbr->flags |= VBLK_REQ_DATA; - - if (unlikely(vbr->flags & VBLK_REQ_FLUSH)) - virtblk_bio_send_flush(vbr); - else - virtblk_bio_send_data(vbr); + if (last) + virtqueue_kick(vblk->vq); + return BLK_MQ_RQ_QUEUE_OK; } /* return id (s/n) string for *disk to *id_str @@ -680,12 +480,35 @@ static const struct device_attribute dev_attr_cache_type_rw = __ATTR(cache_type, S_IRUGO|S_IWUSR, virtblk_cache_type_show, virtblk_cache_type_store); +static struct blk_mq_ops virtio_mq_ops = { + .queue_rq = virtio_queue_rq, + .map_queue = blk_mq_map_queue, + .alloc_hctx = blk_mq_alloc_single_hw_queue, + .free_hctx = blk_mq_free_single_hw_queue, +}; + +static struct blk_mq_reg virtio_mq_reg = { + .ops = &virtio_mq_ops, + .nr_hw_queues = 1, + .queue_depth = 64, + .numa_node = NUMA_NO_NODE, + .flags = BLK_MQ_F_SHOULD_MERGE, +}; + +static void virtblk_init_vbr(void *data, struct blk_mq_hw_ctx *hctx, + struct request *rq, unsigned int nr) +{ + struct virtio_blk *vblk = data; + struct virtblk_req *vbr = rq->special; + + sg_init_table(vbr->sg, vblk->sg_elems); +} + static int virtblk_probe(struct virtio_device *vdev) { struct virtio_blk *vblk; struct request_queue *q; int err, index; - int pool_size; u64 cap; u32 v, blk_size, sg_elems, opt_io_size; @@ -709,17 +532,14 @@ static int virtblk_probe(struct virtio_device *vdev) /* We need an extra sg elements at head and tail. */ sg_elems += 2; - vdev->priv = vblk = kmalloc(sizeof(*vblk) + - sizeof(vblk->sg[0]) * sg_elems, GFP_KERNEL); + vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL); if (!vblk) { err = -ENOMEM; goto out_free_index; } - init_waitqueue_head(&vblk->queue_wait); vblk->vdev = vdev; vblk->sg_elems = sg_elems; - sg_init_table(vblk->sg, vblk->sg_elems); mutex_init(&vblk->config_lock); INIT_WORK(&vblk->config_work, virtblk_config_changed_work); @@ -728,31 +548,27 @@ static int virtblk_probe(struct virtio_device *vdev) err = init_vq(vblk); if (err) goto out_free_vblk; - - pool_size = sizeof(struct virtblk_req); - if (use_bio) - pool_size += sizeof(struct scatterlist) * sg_elems; - vblk->pool = mempool_create_kmalloc_pool(1, pool_size); - if (!vblk->pool) { - err = -ENOMEM; - goto out_free_vq; - } + spin_lock_init(&vblk->vq_lock); /* FIXME: How many partitions? How long is a piece of string? */ vblk->disk = alloc_disk(1 << PART_BITS); if (!vblk->disk) { err = -ENOMEM; - goto out_mempool; + goto out_free_vq; } - q = vblk->disk->queue = blk_init_queue(virtblk_request, NULL); + virtio_mq_reg.cmd_size = + sizeof(struct virtblk_req) + + sizeof(struct scatterlist) * sg_elems; + + q = vblk->disk->queue = blk_mq_init_queue(&virtio_mq_reg, vblk); if (!q) { err = -ENOMEM; goto out_put_disk; } - if (use_bio) - blk_queue_make_request(q, virtblk_make_request); + blk_mq_init_commands(q, virtblk_init_vbr, vblk); + q->queuedata = vblk; virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN); @@ -857,8 +673,6 @@ out_del_disk: blk_cleanup_queue(vblk->disk->queue); out_put_disk: put_disk(vblk->disk); -out_mempool: - mempool_destroy(vblk->pool); out_free_vq: vdev->config->del_vqs(vdev); out_free_vblk: @@ -890,7 +704,6 @@ static void virtblk_remove(struct virtio_device *vdev) refc = atomic_read(&disk_to_dev(vblk->disk)->kobj.kref.refcount); put_disk(vblk->disk); - mempool_destroy(vblk->pool); vdev->config->del_vqs(vdev); kfree(vblk); @@ -914,10 +727,7 @@ static int virtblk_freeze(struct virtio_device *vdev) flush_work(&vblk->config_work); - spin_lock_irq(vblk->disk->queue->queue_lock); - blk_stop_queue(vblk->disk->queue); - spin_unlock_irq(vblk->disk->queue->queue_lock); - blk_sync_queue(vblk->disk->queue); + blk_mq_stop_hw_queues(vblk->disk->queue); vdev->config->del_vqs(vdev); return 0; @@ -930,11 +740,9 @@ static int virtblk_restore(struct virtio_device *vdev) vblk->config_enable = true; ret = init_vq(vdev->priv); - if (!ret) { - spin_lock_irq(vblk->disk->queue->queue_lock); - blk_start_queue(vblk->disk->queue); - spin_unlock_irq(vblk->disk->queue->queue_lock); - } + if (!ret) + blk_mq_start_stopped_hw_queues(vblk->disk->queue); + return ret; } #endif |
