From ff1f48ee3bb3af226f1f8993af0103794b4d4eab Mon Sep 17 00:00:00 2001 From: Richard Weinberger Date: Sat, 10 Jan 2015 22:52:14 +0100 Subject: [PATCH] UBI: Block: Add blk-mq support Convert the driver to blk-mq. Beside of moving to the modern block interface this change boosts also the performance of the driver. nand: device found, Manufacturer ID: 0x2c, Chip ID: 0xda nand: Micron NAND 256MiB 3,3V 8-bit nand: 256MiB, SLC, page size: 2048, OOB size: 64 root@debian-armhf:~# dd if=/dev/ubiblock0_0 of=/dev/zero bs=1M 243+1 records in 243+1 records out 255080448 bytes (255 MB) copied, 4.39295 s, 58.1 MB/s vs. root@debian-armhf:~# dd if=/dev/ubiblock0_0 of=/dev/zero bs=1M 243+1 records in 243+1 records out 255080448 bytes (255 MB) copied, 2.87676 s, 88.7 MB/s Cc: hch@infradead.org Cc: axboe@fb.com Cc: tom.leiming@gmail.com Signed-off-by: Richard Weinberger Tested-by: Ezequiel Garcia Reviewed-by: Jens Axboe Acked-by: Ezequiel Garcia --- drivers/mtd/ubi/block.c | 204 +++++++++++++++++++--------------------- 1 file changed, 95 insertions(+), 109 deletions(-) diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c index 6b6bce28bd63..00caf460337e 100644 --- a/drivers/mtd/ubi/block.c +++ b/drivers/mtd/ubi/block.c @@ -42,11 +42,12 @@ #include #include #include -#include #include #include #include +#include #include +#include #include #include "ubi-media.h" @@ -67,6 +68,11 @@ struct ubiblock_param { char name[UBIBLOCK_PARAM_LEN+1]; }; +struct ubiblock_pdu { + struct work_struct work; + struct ubi_sgl usgl; +}; + /* Numbers of elements set in the @ubiblock_param array */ static int ubiblock_devs __initdata; @@ -84,11 +90,10 @@ struct ubiblock { struct request_queue *rq; struct workqueue_struct *wq; - struct work_struct work; struct mutex dev_mutex; - spinlock_t queue_lock; struct list_head list; + struct blk_mq_tag_set tag_set; }; /* Linked list of all ubiblock instances */ @@ -181,31 +186,20 @@ static struct ubiblock *find_dev_nolock(int ubi_num, int vol_id) return NULL; } -static int ubiblock_read_to_buf(struct ubiblock *dev, char *buffer, - int leb, int offset, int len) +static int ubiblock_read(struct ubiblock_pdu *pdu) { - int ret; + int ret, leb, offset, bytes_left, to_read; + u64 pos; + struct request *req = blk_mq_rq_from_pdu(pdu); + struct ubiblock *dev = req->q->queuedata; - ret = ubi_read(dev->desc, leb, buffer, offset, len); - if (ret) { - dev_err(disk_to_dev(dev->gd), "%d while reading from LEB %d (offset %d, length %d)", - ret, leb, offset, len); - return ret; - } - return 0; -} - -static int ubiblock_read(struct ubiblock *dev, char *buffer, - sector_t sec, int len) -{ - int ret, leb, offset; - int bytes_left = len; - int to_read = len; - u64 pos = sec << 9; + to_read = blk_rq_bytes(req); + pos = blk_rq_pos(req) << 9; /* Get LEB:offset address to read from */ offset = do_div(pos, dev->leb_size); leb = pos; + bytes_left = to_read; while (bytes_left) { /* @@ -215,11 +209,10 @@ static int ubiblock_read(struct ubiblock *dev, char *buffer, if (offset + to_read > dev->leb_size) to_read = dev->leb_size - offset; - ret = ubiblock_read_to_buf(dev, buffer, leb, offset, to_read); - if (ret) + ret = ubi_read_sg(dev->desc, leb, &pdu->usgl, offset, to_read); + if (ret < 0) return ret; - buffer += to_read; bytes_left -= to_read; to_read = bytes_left; leb += 1; @@ -228,79 +221,6 @@ static int ubiblock_read(struct ubiblock *dev, char *buffer, return 0; } -static int do_ubiblock_request(struct ubiblock *dev, struct request *req) -{ - int len, ret; - sector_t sec; - - if (req->cmd_type != REQ_TYPE_FS) - return -EIO; - - if (blk_rq_pos(req) + blk_rq_cur_sectors(req) > - get_capacity(req->rq_disk)) - return -EIO; - - if (rq_data_dir(req) != READ) - return -ENOSYS; /* Write not implemented */ - - sec = blk_rq_pos(req); - len = blk_rq_cur_bytes(req); - - /* - * Let's prevent the device from being removed while we're doing I/O - * work. Notice that this means we serialize all the I/O operations, - * but it's probably of no impact given the NAND core serializes - * flash access anyway. - */ - mutex_lock(&dev->dev_mutex); - ret = ubiblock_read(dev, bio_data(req->bio), sec, len); - mutex_unlock(&dev->dev_mutex); - - return ret; -} - -static void ubiblock_do_work(struct work_struct *work) -{ - struct ubiblock *dev = - container_of(work, struct ubiblock, work); - struct request_queue *rq = dev->rq; - struct request *req; - int res; - - spin_lock_irq(rq->queue_lock); - - req = blk_fetch_request(rq); - while (req) { - - spin_unlock_irq(rq->queue_lock); - res = do_ubiblock_request(dev, req); - spin_lock_irq(rq->queue_lock); - - /* - * If we're done with this request, - * we need to fetch a new one - */ - if (!__blk_end_request_cur(req, res)) - req = blk_fetch_request(rq); - } - - spin_unlock_irq(rq->queue_lock); -} - -static void ubiblock_request(struct request_queue *rq) -{ - struct ubiblock *dev; - struct request *req; - - dev = rq->queuedata; - - if (!dev) - while ((req = blk_fetch_request(rq)) != NULL) - __blk_end_request_all(req, -ENODEV); - else - queue_work(dev->wq, &dev->work); -} - static int ubiblock_open(struct block_device *bdev, fmode_t mode) { struct ubiblock *dev = bdev->bd_disk->private_data; @@ -374,6 +294,57 @@ static const struct block_device_operations ubiblock_ops = { .getgeo = ubiblock_getgeo, }; +static void ubiblock_do_work(struct work_struct *work) +{ + int ret; + struct ubiblock_pdu *pdu = container_of(work, struct ubiblock_pdu, work); + struct request *req = blk_mq_rq_from_pdu(pdu); + + blk_mq_start_request(req); + blk_rq_map_sg(req->q, req, pdu->usgl.sg); + + ret = ubiblock_read(pdu); + blk_mq_end_request(req, ret); +} + +static int ubiblock_queue_rq(struct blk_mq_hw_ctx *hctx, + const struct blk_mq_queue_data *bd) +{ + struct request *req = bd->rq; + struct ubiblock *dev = hctx->queue->queuedata; + struct ubiblock_pdu *pdu = blk_mq_rq_to_pdu(req); + + if (req->cmd_type != REQ_TYPE_FS) + return BLK_MQ_RQ_QUEUE_ERROR; + + if (rq_data_dir(req) != READ) + return BLK_MQ_RQ_QUEUE_ERROR; /* Write not implemented */ + + ubi_sgl_init(&pdu->usgl); + queue_work(dev->wq, &pdu->work); + + return BLK_MQ_RQ_QUEUE_OK; +} + +static int ubiblock_init_request(void *data, struct request *req, + unsigned int hctx_idx, + unsigned int request_idx, + unsigned int numa_node) +{ + struct ubiblock_pdu *pdu = blk_mq_rq_to_pdu(req); + + sg_init_table(pdu->usgl.sg, UBI_MAX_SG_COUNT); + INIT_WORK(&pdu->work, ubiblock_do_work); + + return 0; +} + +static struct blk_mq_ops ubiblock_mq_ops = { + .queue_rq = ubiblock_queue_rq, + .init_request = ubiblock_init_request, + .map_queue = blk_mq_map_queue, +}; + int ubiblock_create(struct ubi_volume_info *vi) { struct ubiblock *dev; @@ -417,14 +388,28 @@ int ubiblock_create(struct ubi_volume_info *vi) set_capacity(gd, disk_capacity); dev->gd = gd; - spin_lock_init(&dev->queue_lock); - dev->rq = blk_init_queue(ubiblock_request, &dev->queue_lock); - if (!dev->rq) { - dev_err(disk_to_dev(gd), "blk_init_queue failed"); - ret = -ENODEV; + dev->tag_set.ops = &ubiblock_mq_ops; + dev->tag_set.queue_depth = 64; + dev->tag_set.numa_node = NUMA_NO_NODE; + dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; + dev->tag_set.cmd_size = sizeof(struct ubiblock_pdu); + dev->tag_set.driver_data = dev; + dev->tag_set.nr_hw_queues = 1; + + ret = blk_mq_alloc_tag_set(&dev->tag_set); + if (ret) { + dev_err(disk_to_dev(dev->gd), "blk_mq_alloc_tag_set failed"); goto out_put_disk; } + dev->rq = blk_mq_init_queue(&dev->tag_set); + if (!dev->rq) { + dev_err(disk_to_dev(gd), "blk_mq_init_queue failed"); + ret = -ENODEV; + goto out_free_tags; + } + blk_queue_max_segments(dev->rq, UBI_MAX_SG_COUNT); + dev->rq->queuedata = dev; dev->gd->queue = dev->rq; @@ -437,7 +422,6 @@ int ubiblock_create(struct ubi_volume_info *vi) ret = -ENOMEM; goto out_free_queue; } - INIT_WORK(&dev->work, ubiblock_do_work); mutex_lock(&devices_mutex); list_add_tail(&dev->list, &ubiblock_devices); @@ -451,6 +435,8 @@ int ubiblock_create(struct ubi_volume_info *vi) out_free_queue: blk_cleanup_queue(dev->rq); +out_free_tags: + blk_mq_free_tag_set(&dev->tag_set); out_put_disk: put_disk(dev->gd); out_free_dev: @@ -461,8 +447,13 @@ out_free_dev: static void ubiblock_cleanup(struct ubiblock *dev) { + /* Stop new requests to arrive */ del_gendisk(dev->gd); + /* Flush pending work */ + destroy_workqueue(dev->wq); + /* Finally destroy the blk queue */ blk_cleanup_queue(dev->rq); + blk_mq_free_tag_set(&dev->tag_set); dev_info(disk_to_dev(dev->gd), "released"); put_disk(dev->gd); } @@ -490,9 +481,6 @@ int ubiblock_remove(struct ubi_volume_info *vi) list_del(&dev->list); mutex_unlock(&devices_mutex); - /* Flush pending work and stop this workqueue */ - destroy_workqueue(dev->wq); - ubiblock_cleanup(dev); mutex_unlock(&dev->dev_mutex); kfree(dev); @@ -620,8 +608,6 @@ static void ubiblock_remove_all(void) struct ubiblock *dev; list_for_each_entry_safe(dev, next, &ubiblock_devices, list) { - /* Flush pending work and stop workqueue */ - destroy_workqueue(dev->wq); /* The module is being forcefully removed */ WARN_ON(dev->desc); /* Remove from device list */