diff options
Diffstat (limited to 'drivers/md/dm.c')
-rw-r--r-- | drivers/md/dm.c | 86 |
1 files changed, 72 insertions, 14 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index aa9e093343d..437d99045ef 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -755,6 +755,14 @@ static void dec_pending(struct dm_io *io, int error) } } +static void disable_write_same(struct mapped_device *md) +{ + struct queue_limits *limits = dm_get_queue_limits(md); + + /* device doesn't really support WRITE SAME, disable it */ + limits->max_write_same_sectors = 0; +} + static void clone_endio(struct bio *bio, int error) { int r = 0; @@ -783,6 +791,10 @@ static void clone_endio(struct bio *bio, int error) } } + if (unlikely(r == -EREMOTEIO && (bio->bi_rw & REQ_WRITE_SAME) && + !bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors)) + disable_write_same(md); + free_tio(md, tio); dec_pending(io, error); } @@ -977,6 +989,10 @@ static void dm_done(struct request *clone, int error, bool mapped) r = rq_end_io(tio->ti, clone, error, &tio->info); } + if (unlikely(r == -EREMOTEIO && (clone->cmd_flags & REQ_WRITE_SAME) && + !clone->q->limits.max_write_same_sectors)) + disable_write_same(tio->md); + if (r <= 0) /* The target wants to complete the I/O */ dm_end_request(clone, r); @@ -1110,6 +1126,46 @@ int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) } EXPORT_SYMBOL_GPL(dm_set_target_max_io_len); +/* + * A target may call dm_accept_partial_bio only from the map routine. It is + * allowed for all bio types except REQ_FLUSH. + * + * dm_accept_partial_bio informs the dm that the target only wants to process + * additional n_sectors sectors of the bio and the rest of the data should be + * sent in a next bio. + * + * A diagram that explains the arithmetics: + * +--------------------+---------------+-------+ + * | 1 | 2 | 3 | + * +--------------------+---------------+-------+ + * + * <-------------- *tio->len_ptr ---------------> + * <------- bi_size -------> + * <-- n_sectors --> + * + * Region 1 was already iterated over with bio_advance or similar function. + * (it may be empty if the target doesn't use bio_advance) + * Region 2 is the remaining bio size that the target wants to process. + * (it may be empty if region 1 is non-empty, although there is no reason + * to make it empty) + * The target requires that region 3 is to be sent in the next bio. + * + * If the target wants to receive multiple copies of the bio (via num_*bios, etc), + * the partially processed part (the sum of regions 1+2) must be the same for all + * copies of the bio. + */ +void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors) +{ + struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); + unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT; + BUG_ON(bio->bi_rw & REQ_FLUSH); + BUG_ON(bi_size > *tio->len_ptr); + BUG_ON(n_sectors > bi_size); + *tio->len_ptr -= bi_size - n_sectors; + bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT; +} +EXPORT_SYMBOL_GPL(dm_accept_partial_bio); + static void __map_bio(struct dm_target_io *tio) { int r; @@ -1152,10 +1208,10 @@ struct clone_info { struct bio *bio; struct dm_io *io; sector_t sector; - sector_t sector_count; + unsigned sector_count; }; -static void bio_setup_sector(struct bio *bio, sector_t sector, sector_t len) +static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) { bio->bi_iter.bi_sector = sector; bio->bi_iter.bi_size = to_bytes(len); @@ -1200,11 +1256,13 @@ static struct dm_target_io *alloc_tio(struct clone_info *ci, static void __clone_and_map_simple_bio(struct clone_info *ci, struct dm_target *ti, - unsigned target_bio_nr, sector_t len) + unsigned target_bio_nr, unsigned *len) { struct dm_target_io *tio = alloc_tio(ci, ti, ci->bio->bi_max_vecs, target_bio_nr); struct bio *clone = &tio->clone; + tio->len_ptr = len; + /* * Discard requests require the bio's inline iovecs be initialized. * ci->bio->bi_max_vecs is BIO_INLINE_VECS anyway, for both flush @@ -1212,13 +1270,13 @@ static void __clone_and_map_simple_bio(struct clone_info *ci, */ __bio_clone_fast(clone, ci->bio); if (len) - bio_setup_sector(clone, ci->sector, len); + bio_setup_sector(clone, ci->sector, *len); __map_bio(tio); } static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, - unsigned num_bios, sector_t len) + unsigned num_bios, unsigned *len) { unsigned target_bio_nr; @@ -1233,13 +1291,13 @@ static int __send_empty_flush(struct clone_info *ci) BUG_ON(bio_has_data(ci->bio)); while ((ti = dm_table_get_target(ci->map, target_nr++))) - __send_duplicate_bios(ci, ti, ti->num_flush_bios, 0); + __send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL); return 0; } static void __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, - sector_t sector, unsigned len) + sector_t sector, unsigned *len) { struct bio *bio = ci->bio; struct dm_target_io *tio; @@ -1254,7 +1312,8 @@ static void __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti for (target_bio_nr = 0; target_bio_nr < num_target_bios; target_bio_nr++) { tio = alloc_tio(ci, ti, 0, target_bio_nr); - clone_bio(tio, bio, sector, len); + tio->len_ptr = len; + clone_bio(tio, bio, sector, *len); __map_bio(tio); } } @@ -1283,7 +1342,7 @@ static int __send_changing_extent_only(struct clone_info *ci, is_split_required_fn is_split_required) { struct dm_target *ti; - sector_t len; + unsigned len; unsigned num_bios; do { @@ -1302,11 +1361,11 @@ static int __send_changing_extent_only(struct clone_info *ci, return -EOPNOTSUPP; if (is_split_required && !is_split_required(ti)) - len = min(ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); + len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); else - len = min(ci->sector_count, max_io_len(ci->sector, ti)); + len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti)); - __send_duplicate_bios(ci, ti, num_bios, len); + __send_duplicate_bios(ci, ti, num_bios, &len); ci->sector += len; } while (ci->sector_count -= len); @@ -1345,7 +1404,7 @@ static int __split_and_process_non_flush(struct clone_info *ci) len = min_t(sector_t, max_io_len(ci->sector, ti), ci->sector_count); - __clone_and_map_data_bio(ci, ti, ci->sector, len); + __clone_and_map_data_bio(ci, ti, ci->sector, &len); ci->sector += len; ci->sector_count -= len; @@ -1439,7 +1498,6 @@ static int dm_merge_bvec(struct request_queue *q, * just one page. */ else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9) - max_size = 0; out: |