From 655f3aad7aa4858d06cdaca6c4b14635cc3c0eba Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Sat, 19 Mar 2022 18:04:20 -0400 Subject: [PATCH] dm: switch dm_target_io booleans over to proper flags Add flags to dm_target_io and manage them using the same pattern used for bi_flags in struct bio. Signed-off-by: Mike Snitzer --- drivers/md/dm-core.h | 21 +++++++++++++++++++-- drivers/md/dm.c | 31 +++++++++++++++++++------------ 2 files changed, 38 insertions(+), 14 deletions(-) diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h index e127cbc..feb5323 100644 --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -215,13 +215,30 @@ struct dm_target_io { struct dm_io *io; struct dm_target *ti; unsigned int *len_ptr; - bool inside_dm_io:1; - bool is_duplicate_bio:1; + unsigned short flags; sector_t old_sector; struct bio clone; }; /* + * dm_target_io flags + */ +enum { + DM_TIO_INSIDE_DM_IO, + DM_TIO_IS_DUPLICATE_BIO +}; + +static inline bool dm_tio_flagged(struct dm_target_io *tio, unsigned int bit) +{ + return (tio->flags & (1U << bit)) != 0; +} + +static inline void dm_tio_set_flag(struct dm_target_io *tio, unsigned int bit) +{ + tio->flags |= (1U << bit); +} + +/* * One of these is allocated per original bio. * It contains the first clone used for that original. */ diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 83328f0..cca11cf 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -94,7 +94,7 @@ static inline struct dm_target_io *clone_to_tio(struct bio *clone) void *dm_per_bio_data(struct bio *bio, size_t data_size) { - if (!clone_to_tio(bio)->inside_dm_io) + if (!dm_tio_flagged(clone_to_tio(bio), DM_TIO_INSIDE_DM_IO)) return (char *)bio - DM_TARGET_IO_BIO_OFFSET - data_size; return (char *)bio - DM_IO_BIO_OFFSET - data_size; } @@ -538,9 +538,10 @@ static void dm_start_io_acct(struct dm_io *io, struct bio *clone) /* * Ensure IO accounting is only ever started once. - * Expect no possibility for race unless is_duplicate_bio. + * Expect no possibility for race unless DM_TIO_IS_DUPLICATE_BIO. */ - if (!clone || likely(!clone_to_tio(clone)->is_duplicate_bio)) { + if (!clone || + likely(!dm_tio_flagged(clone_to_tio(clone), DM_TIO_IS_DUPLICATE_BIO))) { if (WARN_ON_ONCE(dm_io_flagged(io, DM_IO_ACCOUNTED))) return; dm_io_set_flag(io, DM_IO_ACCOUNTED); @@ -548,7 +549,7 @@ static void dm_start_io_acct(struct dm_io *io, struct bio *clone) unsigned long flags; if (dm_io_flagged(io, DM_IO_ACCOUNTED)) return; - /* Can afford locking given is_duplicate_bio */ + /* Can afford locking given DM_TIO_IS_DUPLICATE_BIO */ spin_lock_irqsave(&io->startio_lock, flags); dm_io_set_flag(io, DM_IO_ACCOUNTED); spin_unlock_irqrestore(&io->startio_lock, flags); @@ -571,7 +572,8 @@ static struct dm_io *alloc_io(struct mapped_device *md, struct bio *bio) clone = bio_alloc_clone(bio->bi_bdev, bio, GFP_NOIO, &md->io_bs); tio = clone_to_tio(clone); - tio->inside_dm_io = true; + tio->flags = 0; + dm_tio_set_flag(tio, DM_TIO_INSIDE_DM_IO); tio->io = NULL; io = container_of(tio, struct dm_io, tio); @@ -618,14 +620,13 @@ static struct bio *alloc_tio(struct clone_info *ci, struct dm_target *ti, clone->bi_opf &= ~REQ_DM_POLL_LIST; tio = clone_to_tio(clone); - tio->inside_dm_io = false; + tio->flags = 0; /* also clears DM_TIO_INSIDE_DM_IO */ } tio->magic = DM_TIO_MAGIC; tio->io = ci->io; tio->ti = ti; tio->target_bio_nr = target_bio_nr; - tio->is_duplicate_bio = false; tio->len_ptr = len; tio->old_sector = 0; @@ -640,7 +641,7 @@ static struct bio *alloc_tio(struct clone_info *ci, struct dm_target *ti, static void free_tio(struct bio *clone) { - if (clone_to_tio(clone)->inside_dm_io) + if (dm_tio_flagged(clone_to_tio(clone), DM_TIO_INSIDE_DM_IO)) return; bio_put(clone); } @@ -917,6 +918,12 @@ static void dm_io_complete(struct dm_io *io) } } +static inline bool dm_tio_is_normal(struct dm_target_io *tio) +{ + return (dm_tio_flagged(tio, DM_TIO_INSIDE_DM_IO) && + !dm_tio_flagged(tio, DM_TIO_IS_DUPLICATE_BIO)); +} + /* * Decrements the number of outstanding ios that a bio has been * cloned into, completing the original io if necc. @@ -1180,7 +1187,7 @@ void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors) struct dm_target_io *tio = clone_to_tio(bio); unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT; - BUG_ON(tio->is_duplicate_bio); + BUG_ON(dm_tio_flagged(tio, DM_TIO_IS_DUPLICATE_BIO)); BUG_ON(op_is_zone_mgmt(bio_op(bio))); BUG_ON(bio_op(bio) == REQ_OP_ZONE_APPEND); BUG_ON(bi_size > *tio->len_ptr); @@ -1362,13 +1369,13 @@ static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, break; case 1: clone = alloc_tio(ci, ti, 0, len, GFP_NOIO); - clone_to_tio(clone)->is_duplicate_bio = true; + dm_tio_set_flag(clone_to_tio(clone), DM_TIO_IS_DUPLICATE_BIO); __map_bio(clone); break; default: alloc_multiple_bios(&blist, ci, ti, num_bios, len); while ((clone = bio_list_pop(&blist))) { - clone_to_tio(clone)->is_duplicate_bio = true; + dm_tio_set_flag(clone_to_tio(clone), DM_TIO_IS_DUPLICATE_BIO); __map_bio(clone); } break; @@ -1648,7 +1655,7 @@ out: static bool dm_poll_dm_io(struct dm_io *io, struct io_comp_batch *iob, unsigned int flags) { - WARN_ON_ONCE(!io->tio.inside_dm_io); + WARN_ON_ONCE(!dm_tio_is_normal(&io->tio)); /* don't poll if the mapped io is done */ if (atomic_read(&io->io_count) > 1) -- 2.7.4