diff options
author | Christoph Hellwig <hch@lst.de> | 2021-10-12 14:12:24 +0300 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2021-10-18 15:17:36 +0300 |
commit | 3e08773c3841e9db7a520908cc2b136a77d275ff (patch) | |
tree | 5dce4a3944899f0eb1370a92130e89134da2a714 /drivers/md | |
parent | 19416123ab3e1348b3532347af221d8f60838431 (diff) | |
download | linux-3e08773c3841e9db7a520908cc2b136a77d275ff.tar.xz |
block: switch polling to be bio based
Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.
Polling for the bio itself leads to a few advantages:
- the cookie construction can made entirely private in blk-mq.c
- the caller does not need to remember the request_queue and cookie
separately and thus sidesteps their lifetime issues
- keeping the device and the cookie inside the bio allows to trivially
support polling BIOs remapping by stacking drivers
- a lot of code to propagate the cookie back up the submission path can
be removed entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/bcache/request.c | 13 | ||||
-rw-r--r-- | drivers/md/bcache/request.h | 4 | ||||
-rw-r--r-- | drivers/md/dm.c | 28 | ||||
-rw-r--r-- | drivers/md/md.c | 10 |
4 files changed, 21 insertions, 34 deletions
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c index 6d1de889baeb..23b28edae90f 100644 --- a/drivers/md/bcache/request.c +++ b/drivers/md/bcache/request.c @@ -1163,7 +1163,7 @@ static void quit_max_writeback_rate(struct cache_set *c, /* Cached devices - read & write stuff */ -blk_qc_t cached_dev_submit_bio(struct bio *bio) +void cached_dev_submit_bio(struct bio *bio) { struct search *s; struct block_device *orig_bdev = bio->bi_bdev; @@ -1176,7 +1176,7 @@ blk_qc_t cached_dev_submit_bio(struct bio *bio) dc->io_disable)) { bio->bi_status = BLK_STS_IOERR; bio_endio(bio); - return BLK_QC_T_NONE; + return; } if (likely(d->c)) { @@ -1222,8 +1222,6 @@ blk_qc_t cached_dev_submit_bio(struct bio *bio) } else /* I/O request sent to backing device */ detached_dev_do_request(d, bio, orig_bdev, start_time); - - return BLK_QC_T_NONE; } static int cached_dev_ioctl(struct bcache_device *d, fmode_t mode, @@ -1273,7 +1271,7 @@ static void flash_dev_nodata(struct closure *cl) continue_at(cl, search_free, NULL); } -blk_qc_t flash_dev_submit_bio(struct bio *bio) +void flash_dev_submit_bio(struct bio *bio) { struct search *s; struct closure *cl; @@ -1282,7 +1280,7 @@ blk_qc_t flash_dev_submit_bio(struct bio *bio) if (unlikely(d->c && test_bit(CACHE_SET_IO_DISABLE, &d->c->flags))) { bio->bi_status = BLK_STS_IOERR; bio_endio(bio); - return BLK_QC_T_NONE; + return; } s = search_alloc(bio, d, bio->bi_bdev, bio_start_io_acct(bio)); @@ -1298,7 +1296,7 @@ blk_qc_t flash_dev_submit_bio(struct bio *bio) continue_at_nobarrier(&s->cl, flash_dev_nodata, bcache_wq); - return BLK_QC_T_NONE; + return; } else if (bio_data_dir(bio)) { bch_keybuf_check_overlapping(&s->iop.c->moving_gc_keys, &KEY(d->id, bio->bi_iter.bi_sector, 0), @@ -1314,7 +1312,6 @@ blk_qc_t flash_dev_submit_bio(struct bio *bio) } continue_at(cl, search_free, NULL); - return BLK_QC_T_NONE; } static int flash_dev_ioctl(struct bcache_device *d, fmode_t mode, diff --git a/drivers/md/bcache/request.h b/drivers/md/bcache/request.h index 82b38366a95d..38ab4856eaab 100644 --- a/drivers/md/bcache/request.h +++ b/drivers/md/bcache/request.h @@ -37,10 +37,10 @@ unsigned int bch_get_congested(const struct cache_set *c); void bch_data_insert(struct closure *cl); void bch_cached_dev_request_init(struct cached_dev *dc); -blk_qc_t cached_dev_submit_bio(struct bio *bio); +void cached_dev_submit_bio(struct bio *bio); void bch_flash_dev_request_init(struct bcache_device *d); -blk_qc_t flash_dev_submit_bio(struct bio *bio); +void flash_dev_submit_bio(struct bio *bio); extern struct kmem_cache *bch_search_cache; diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 76d9da49fda7..7870e6460633 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1183,14 +1183,13 @@ static noinline void __set_swap_bios_limit(struct mapped_device *md, int latch) mutex_unlock(&md->swap_bios_lock); } -static blk_qc_t __map_bio(struct dm_target_io *tio) +static void __map_bio(struct dm_target_io *tio) { int r; sector_t sector; struct bio *clone = &tio->clone; struct dm_io *io = tio->io; struct dm_target *ti = tio->ti; - blk_qc_t ret = BLK_QC_T_NONE; clone->bi_end_io = clone_endio; @@ -1226,7 +1225,7 @@ static blk_qc_t __map_bio(struct dm_target_io *tio) case DM_MAPIO_REMAPPED: /* the bio has been remapped so dispatch it */ trace_block_bio_remap(clone, bio_dev(io->orig_bio), sector); - ret = submit_bio_noacct(clone); + submit_bio_noacct(clone); break; case DM_MAPIO_KILL: if (unlikely(swap_bios_limit(ti, clone))) { @@ -1248,8 +1247,6 @@ static blk_qc_t __map_bio(struct dm_target_io *tio) DMWARN("unimplemented target map return value: %d", r); BUG(); } - - return ret; } static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) @@ -1336,7 +1333,7 @@ static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci, } } -static blk_qc_t __clone_and_map_simple_bio(struct clone_info *ci, +static void __clone_and_map_simple_bio(struct clone_info *ci, struct dm_target_io *tio, unsigned *len) { struct bio *clone = &tio->clone; @@ -1346,8 +1343,7 @@ static blk_qc_t __clone_and_map_simple_bio(struct clone_info *ci, __bio_clone_fast(clone, ci->bio); if (len) bio_setup_sector(clone, ci->sector, *len); - - return __map_bio(tio); + __map_bio(tio); } static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, @@ -1361,7 +1357,7 @@ static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, while ((bio = bio_list_pop(&blist))) { tio = container_of(bio, struct dm_target_io, clone); - (void) __clone_and_map_simple_bio(ci, tio, len); + __clone_and_map_simple_bio(ci, tio, len); } } @@ -1405,7 +1401,7 @@ static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, free_tio(tio); return r; } - (void) __map_bio(tio); + __map_bio(tio); return 0; } @@ -1520,11 +1516,10 @@ static void init_clone_info(struct clone_info *ci, struct mapped_device *md, /* * Entry point to split a bio into clones and submit them to the targets. */ -static blk_qc_t __split_and_process_bio(struct mapped_device *md, +static void __split_and_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); @@ -1567,19 +1562,17 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md, bio_chain(b, bio); trace_block_split(b, bio->bi_iter.bi_sector); - ret = submit_bio_noacct(bio); + submit_bio_noacct(bio); } } /* drop the extra reference count */ dm_io_dec_pending(ci.io, errno_to_blk_status(error)); - return ret; } -static blk_qc_t dm_submit_bio(struct bio *bio) +static void dm_submit_bio(struct bio *bio) { struct mapped_device *md = bio->bi_bdev->bd_disk->private_data; - blk_qc_t ret = BLK_QC_T_NONE; int srcu_idx; struct dm_table *map; @@ -1609,10 +1602,9 @@ static blk_qc_t dm_submit_bio(struct bio *bio) if (is_abnormal_io(bio)) blk_queue_split(&bio); - ret = __split_and_process_bio(md, map, bio); + __split_and_process_bio(md, map, bio); out: dm_put_live_table(md, srcu_idx); - return ret; } /*----------------------------------------------------------------- diff --git a/drivers/md/md.c b/drivers/md/md.c index ec09083ff0ef..22310d5d8d41 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -443,19 +443,19 @@ check_suspended: } EXPORT_SYMBOL(md_handle_request); -static blk_qc_t md_submit_bio(struct bio *bio) +static void md_submit_bio(struct bio *bio) { const int rw = bio_data_dir(bio); struct mddev *mddev = bio->bi_bdev->bd_disk->private_data; if (mddev == NULL || mddev->pers == NULL) { bio_io_error(bio); - return BLK_QC_T_NONE; + return; } if (unlikely(test_bit(MD_BROKEN, &mddev->flags)) && (rw == WRITE)) { bio_io_error(bio); - return BLK_QC_T_NONE; + return; } blk_queue_split(&bio); @@ -464,15 +464,13 @@ static blk_qc_t md_submit_bio(struct bio *bio) if (bio_sectors(bio) != 0) bio->bi_status = BLK_STS_IOERR; bio_endio(bio); - return BLK_QC_T_NONE; + return; } /* bio could be mergeable after passing to underlayer */ bio->bi_opf &= ~REQ_NOMERGE; md_handle_request(mddev, bio); - - return BLK_QC_T_NONE; } /* mddev_suspend makes sure no new requests are submitted |