From 9c37de297f6590937f95a28bec1b7ac68a38618f Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Wed, 7 Oct 2020 15:15:08 -0400 Subject: [PATCH] dm: remove special-casing of bio-based immutable singleton target on NVMe Since commit 5a6c35f9af416 ("block: remove direct_make_request") there is no benefit to DM special-casing NVMe. Remove all code used to establish DM_TYPE_NVME_BIO_BASED. Signed-off-by: Mike Snitzer --- drivers/md/dm-table.c | 32 ++----------------------- drivers/md/dm.c | 55 ++++--------------------------------------- include/linux/device-mapper.h | 1 - 3 files changed, 7 insertions(+), 81 deletions(-) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 3ad22ad..ce543b7 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -804,8 +804,7 @@ EXPORT_SYMBOL(dm_consume_args); static bool __table_type_bio_based(enum dm_queue_mode table_type) { return (table_type == DM_TYPE_BIO_BASED || - table_type == DM_TYPE_DAX_BIO_BASED || - table_type == DM_TYPE_NVME_BIO_BASED); + table_type == DM_TYPE_DAX_BIO_BASED); } static bool __table_type_request_based(enum dm_queue_mode table_type) @@ -861,8 +860,6 @@ bool dm_table_supports_dax(struct dm_table *t, return true; } -static bool dm_table_does_not_support_partial_completion(struct dm_table *t); - static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev, sector_t start, sector_t len, void *data) { @@ -892,7 +889,6 @@ static int dm_table_determine_type(struct dm_table *t) goto verify_bio_based; } BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED); - BUG_ON(t->type == DM_TYPE_NVME_BIO_BASED); goto verify_rq_based; } @@ -931,15 +927,6 @@ verify_bio_based: if (dm_table_supports_dax(t, device_supports_dax, &page_size) || (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) { t->type = DM_TYPE_DAX_BIO_BASED; - } else { - /* Check if upgrading to NVMe bio-based is valid or required */ - tgt = dm_table_get_immutable_target(t); - if (tgt && !tgt->max_io_len && dm_table_does_not_support_partial_completion(t)) { - t->type = DM_TYPE_NVME_BIO_BASED; - goto verify_rq_based; /* must be stacked directly on NVMe (blk-mq) */ - } else if (list_empty(devices) && live_md_type == DM_TYPE_NVME_BIO_BASED) { - t->type = DM_TYPE_NVME_BIO_BASED; - } } return 0; } @@ -956,8 +943,7 @@ verify_rq_based: * (e.g. request completion process for partial completion.) */ if (t->num_targets > 1) { - DMERR("%s DM doesn't support multiple targets", - t->type == DM_TYPE_NVME_BIO_BASED ? "nvme bio-based" : "request-based"); + DMERR("request-based DM doesn't support multiple targets"); return -EINVAL; } @@ -1651,20 +1637,6 @@ static bool dm_table_all_devices_attribute(struct dm_table *t, return true; } -static int device_no_partial_completion(struct dm_target *ti, struct dm_dev *dev, - sector_t start, sector_t len, void *data) -{ - char b[BDEVNAME_SIZE]; - - /* For now, NVMe devices are the only devices of this class */ - return (strncmp(bdevname(dev->bdev, b), "nvme", 4) == 0); -} - -static bool dm_table_does_not_support_partial_completion(struct dm_table *t) -{ - return dm_table_all_devices_attribute(t, device_no_partial_completion); -} - static int device_not_write_same_capable(struct dm_target *ti, struct dm_dev *dev, sector_t start, sector_t len, void *data) { diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 32ac196..af1bab3 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -975,7 +975,7 @@ static void clone_endio(struct bio *bio) dm_endio_fn endio = tio->ti->type->end_io; struct bio *orig_bio = io->orig_bio; - if (unlikely(error == BLK_STS_TARGET) && md->type != DM_TYPE_NVME_BIO_BASED) { + if (unlikely(error == BLK_STS_TARGET)) { if (bio_op(bio) == REQ_OP_DISCARD && !bio->bi_disk->queue->limits.max_discard_sectors) disable_discard(md); @@ -1626,45 +1626,6 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md, return ret; } -/* - * Optimized variant of __split_and_process_bio that leverages the - * fact that targets that use it do _not_ have a need to split bios. - */ -static blk_qc_t __process_bio(struct mapped_device *md, struct dm_table *map, - struct bio *bio) -{ - struct clone_info ci; - blk_qc_t ret = BLK_QC_T_NONE; - int error = 0; - - init_clone_info(&ci, md, map, bio); - - if (bio->bi_opf & REQ_PREFLUSH) { - error = __send_empty_flush(&ci); - /* dec_pending submits any data associated with flush */ - } else { - struct dm_target_io *tio; - struct dm_target *ti = md->immutable_target; - - if (WARN_ON_ONCE(!ti)) { - error = -EIO; - goto out; - } - - ci.bio = bio; - ci.sector_count = bio_sectors(bio); - if (__process_abnormal_io(&ci, ti, &error)) - goto out; - - tio = alloc_tio(&ci, ti, 0, GFP_NOIO); - ret = __clone_and_map_simple_bio(&ci, tio, NULL); - } -out: - /* drop the extra reference count */ - dec_pending(ci.io, errno_to_blk_status(error)); - return ret; -} - static blk_qc_t dm_submit_bio(struct bio *bio) { struct mapped_device *md = bio->bi_disk->private_data; @@ -1710,10 +1671,7 @@ static blk_qc_t dm_submit_bio(struct bio *bio) if (is_abnormal_io(bio)) blk_queue_split(&bio); - if (dm_get_md_type(md) == DM_TYPE_NVME_BIO_BASED) - ret = __process_bio(md, map, bio); - else - ret = __split_and_process_bio(md, map, bio); + ret = __split_and_process_bio(md, map, bio); out: dm_put_live_table(md, srcu_idx); return ret; @@ -2038,11 +1996,10 @@ static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, if (request_based) dm_stop_queue(q); - if (request_based || md->type == DM_TYPE_NVME_BIO_BASED) { + if (request_based) { /* - * Leverage the fact that request-based DM targets and - * NVMe bio based targets are immutable singletons - * - used to optimize both __process_bio and dm_mq_queue_rq + * Leverage the fact that request-based DM targets are + * immutable singletons - used to optimize dm_mq_queue_rq. */ md->immutable_target = dm_table_get_immutable_target(t); } @@ -2164,7 +2121,6 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t) break; case DM_TYPE_BIO_BASED: case DM_TYPE_DAX_BIO_BASED: - case DM_TYPE_NVME_BIO_BASED: break; case DM_TYPE_NONE: WARN_ON_ONCE(true); @@ -2922,7 +2878,6 @@ struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_qu switch (type) { case DM_TYPE_BIO_BASED: case DM_TYPE_DAX_BIO_BASED: - case DM_TYPE_NVME_BIO_BASED: pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size); front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone); io_front_pad = roundup(front_pad, __alignof__(struct dm_io)) + offsetof(struct dm_io, tio); diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index d6f8d4b..61a66fb 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -29,7 +29,6 @@ enum dm_queue_mode { DM_TYPE_BIO_BASED = 1, DM_TYPE_REQUEST_BASED = 2, DM_TYPE_DAX_BIO_BASED = 3, - DM_TYPE_NVME_BIO_BASED = 4, }; typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t; -- 2.7.4