Flush requests are implemented as REQ_OP_WRITE + REQ_OP_PREFLUSH combination and not REQ_OP_FLUSH + REQ_PREFLUSH combination. This unclear nature has lead to the confusion and bugs in the code for block drivers causing more work for testing, reviews and fixes :- 1. https://lore.kernel.org/all/ZFHgefWofVt24tRl@xxxxxxxxxxxxx/ 2. https://marc.info/?l=linux-block&m=168386364026498&w=2 Add a macro (name can me more meaningful) with a meaningful comment clearing the confusion and replace the REQ_OP_WRITE | REQ_PREFLUSH with the new macro name that also saves code repetation. Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx> --- block/blk-flush.c | 2 +- drivers/md/bcache/request.c | 3 +-- drivers/md/dm-bufio.c | 2 +- drivers/md/dm-integrity.c | 2 +- drivers/md/dm-log.c | 2 +- drivers/md/dm-raid1.c | 2 +- drivers/md/dm-snap-persistent.c | 5 ++--- drivers/md/dm-writecache.c | 2 +- drivers/md/dm.c | 2 +- drivers/md/md.c | 3 +-- drivers/md/raid5-cache.c | 3 +-- drivers/md/raid5-ppl.c | 3 +-- drivers/nvme/target/io-cmd-bdev.c | 2 +- drivers/target/target_core_iblock.c | 3 +-- include/linux/blk_types.h | 7 +++++++ 15 files changed, 22 insertions(+), 21 deletions(-) diff --git a/block/blk-flush.c b/block/blk-flush.c index 04698ed9bcd4..376f00257100 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -460,7 +460,7 @@ int blkdev_issue_flush(struct block_device *bdev) { struct bio bio; - bio_init(&bio, bdev, NULL, 0, REQ_OP_WRITE | REQ_PREFLUSH); + bio_init(&bio, bdev, NULL, 0, REQ_FLUSH_OPF); return submit_bio_wait(&bio); } EXPORT_SYMBOL(blkdev_issue_flush); diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c index 67a2e29e0b40..ab89897a36a2 100644 --- a/drivers/md/bcache/request.c +++ b/drivers/md/bcache/request.c @@ -1023,8 +1023,7 @@ static void cached_dev_write(struct cached_dev *dc, struct search *s) */ struct bio *flush; - flush = bio_alloc_bioset(bio->bi_bdev, 0, - REQ_OP_WRITE | REQ_PREFLUSH, + flush = bio_alloc_bioset(bio->bi_bdev, 0, REQ_FLUSH_OPF, GFP_NOIO, &dc->disk.bio_split); if (!flush) { s->iop.status = BLK_STS_RESOURCE; diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index eea977662e81..da815325842b 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -2133,7 +2133,7 @@ EXPORT_SYMBOL_GPL(dm_bufio_write_dirty_buffers); int dm_bufio_issue_flush(struct dm_bufio_client *c) { struct dm_io_request io_req = { - .bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC, + .bi_opf = REQ_FLUSH_OPF | REQ_SYNC, .mem.type = DM_IO_KMEM, .mem.ptr.addr = NULL, .client = c->dm_io, diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 31838b13ea54..2d90f8ad1ae5 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -1533,7 +1533,7 @@ static void dm_integrity_flush_buffers(struct dm_integrity_c *ic, bool flush_dat if (!ic->meta_dev) flush_data = false; if (flush_data) { - fr.io_req.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC, + fr.io_req.bi_opf = REQ_FLUSH_OPF | REQ_SYNC, fr.io_req.mem.type = DM_IO_KMEM, fr.io_req.mem.ptr.addr = NULL, fr.io_req.notify.fn = flush_notify, diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c index f9f84236dfcd..2c40f865ef16 100644 --- a/drivers/md/dm-log.c +++ b/drivers/md/dm-log.c @@ -311,7 +311,7 @@ static int flush_header(struct log_c *lc) .count = 0, }; - lc->io_req.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; + lc->io_req.bi_opf = REQ_FLUSH_OPF; return dm_io(&lc->io_req, 1, &null_location, NULL); } diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c index ddcb2bc4a617..7acb9a390b38 100644 --- a/drivers/md/dm-raid1.c +++ b/drivers/md/dm-raid1.c @@ -265,7 +265,7 @@ static int mirror_flush(struct dm_target *ti) struct dm_io_region io[MAX_NR_MIRRORS]; struct mirror *m; struct dm_io_request io_req = { - .bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC, + .bi_opf = REQ_FLUSH_OPF | REQ_SYNC, .mem.type = DM_IO_KMEM, .mem.ptr.addr = NULL, .client = ms->io_client, diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c index 15649921f2a9..cfb7f1b92c5e 100644 --- a/drivers/md/dm-snap-persistent.c +++ b/drivers/md/dm-snap-persistent.c @@ -739,8 +739,7 @@ static void persistent_commit_exception(struct dm_exception_store *store, /* * Commit exceptions to disk. */ - if (ps->valid && area_io(ps, REQ_OP_WRITE | REQ_PREFLUSH | REQ_FUA | - REQ_SYNC)) + if (ps->valid && area_io(ps, REQ_FLUSH_OPF | REQ_FUA | REQ_SYNC)) ps->valid = 0; /* @@ -817,7 +816,7 @@ static int persistent_commit_merge(struct dm_exception_store *store, for (i = 0; i < nr_merged; i++) clear_exception(ps, ps->current_committed - 1 - i); - r = area_io(ps, REQ_OP_WRITE | REQ_PREFLUSH | REQ_FUA); + r = area_io(ps, REQ_FLUSH_OPF | REQ_FUA); if (r < 0) return r; diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c index 074cb785eafc..538f74114d13 100644 --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -590,7 +590,7 @@ static void writecache_disk_flush(struct dm_writecache *wc, struct dm_dev *dev) region.bdev = dev->bdev; region.sector = 0; region.count = 0; - req.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; + req.bi_opf = REQ_FLUSH_OPF; req.mem.type = DM_IO_KMEM; req.mem.ptr.addr = NULL; req.client = wc->dm_io; diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 3b694ba3a106..a570024a747d 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1555,7 +1555,7 @@ static void __send_empty_flush(struct clone_info *ci) * the basis for the clone(s). */ bio_init(&flush_bio, ci->io->md->disk->part0, NULL, 0, - REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC); + REQ_FLUSH_OPF | REQ_SYNC); ci->bio = &flush_bio; ci->sector_count = 0; diff --git a/drivers/md/md.c b/drivers/md/md.c index 8e344b4b3444..5f72a693dc1c 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -533,8 +533,7 @@ static void submit_flushes(struct work_struct *ws) atomic_inc(&rdev->nr_pending); atomic_inc(&rdev->nr_pending); rcu_read_unlock(); - bi = bio_alloc_bioset(rdev->bdev, 0, - REQ_OP_WRITE | REQ_PREFLUSH, + bi = bio_alloc_bioset(rdev->bdev, 0, REQ_FLUSH_OPF, GFP_NOIO, &mddev->bio_set); bi->bi_end_io = md_end_flush; bi->bi_private = rdev; diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c index 46182b955aef..692c3ed33b1f 100644 --- a/drivers/md/raid5-cache.c +++ b/drivers/md/raid5-cache.c @@ -1303,8 +1303,7 @@ void r5l_flush_stripe_to_raid(struct r5l_log *log) if (!do_flush) return; - bio_init(&log->flush_bio, log->rdev->bdev, NULL, 0, - REQ_OP_WRITE | REQ_PREFLUSH); + bio_init(&log->flush_bio, log->rdev->bdev, NULL, 0, REQ_FLUSH_OPF); log->flush_bio.bi_end_io = r5l_log_flush_endio; submit_bio(&log->flush_bio); } diff --git a/drivers/md/raid5-ppl.c b/drivers/md/raid5-ppl.c index e495939bb3e0..da2012744b0d 100644 --- a/drivers/md/raid5-ppl.c +++ b/drivers/md/raid5-ppl.c @@ -629,8 +629,7 @@ static void ppl_do_flush(struct ppl_io_unit *io) if (bdev) { struct bio *bio; - bio = bio_alloc_bioset(bdev, 0, - REQ_OP_WRITE | REQ_PREFLUSH, + bio = bio_alloc_bioset(bdev, 0, REQ_FLUSH_OPF, GFP_NOIO, &ppl_conf->flush_bs); bio->bi_private = io; bio->bi_end_io = ppl_flush_endio; diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c index c2d6cea0236b..2717b64cb02f 100644 --- a/drivers/nvme/target/io-cmd-bdev.c +++ b/drivers/nvme/target/io-cmd-bdev.c @@ -342,7 +342,7 @@ static void nvmet_bdev_execute_flush(struct nvmet_req *req) return; bio_init(bio, req->ns->bdev, req->inline_bvec, - ARRAY_SIZE(req->inline_bvec), REQ_OP_WRITE | REQ_PREFLUSH); + ARRAY_SIZE(req->inline_bvec), REQ_FLUSH_OPF); bio->bi_private = req; bio->bi_end_io = nvmet_bio_done; diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c index cc838ffd1294..01984d07ff9c 100644 --- a/drivers/target/target_core_iblock.c +++ b/drivers/target/target_core_iblock.c @@ -419,8 +419,7 @@ iblock_execute_sync_cache(struct se_cmd *cmd) if (immed) target_complete_cmd(cmd, SAM_STAT_GOOD); - bio = bio_alloc(ib_dev->ibd_bd, 0, REQ_OP_WRITE | REQ_PREFLUSH, - GFP_KERNEL); + bio = bio_alloc(ib_dev->ibd_bd, 0, REQ_FLUSH_OPF, GFP_KERNEL); bio->bi_end_io = iblock_end_io_flush; if (!immed) bio->bi_private = cmd; diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 740afe80f297..f3afdbb3f239 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -455,6 +455,13 @@ enum req_flag_bits { #define REQ_NOMERGE_FLAGS \ (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA) +/* + * Flush requests are implemented as REQ_OP_WRITE + REQ_OP_PREFLUSH combination + * and not REQ_OP_FLUSH + REQ_PREFLUSH combination. + */ + +#define REQ_FLUSH_OPF (REQ_OP_WRITE | REQ_PREFLUSH) + enum stat_group { STAT_READ, STAT_WRITE, -- 2.40.0
