From 3d7f45625a84696f61c6470a887bdc65180937a9 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Fri, 8 Dec 2017 15:02:11 -0500 Subject: [PATCH] dm: fix __send_changing_extent_only() to send first bio and chain remainder __send_changing_extent_only() must follow the same pattern that was established with commit "dm: ensure bio submission follows a depth-first tree walk". That is: submit first bio up to split boundary and then split the remainder to further submissions. Suggested-by: Mikulas Patocka Signed-off-by: Mike Snitzer --- drivers/md/dm.c | 66 ++++++++++++++++++++++--------------------------- 1 file changed, 30 insertions(+), 36 deletions(-) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 9d255e5c9688..4e7682afebfa 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1348,56 +1348,50 @@ static bool is_split_required_for_discard(struct dm_target *ti) return ti->split_discard_bios; } -static int __send_changing_extent_only(struct clone_info *ci, +static int __send_changing_extent_only(struct clone_info *ci, struct dm_target *ti, get_num_bios_fn get_num_bios, is_split_required_fn is_split_required) { - struct dm_target *ti; unsigned len; unsigned num_bios; - do { - ti = dm_table_find_target(ci->map, ci->sector); - if (!dm_target_is_valid(ti)) - return -EIO; + /* + * Even though the device advertised support for this type of + * request, that does not mean every target supports it, and + * reconfiguration might also have changed that since the + * check was performed. + */ + num_bios = get_num_bios ? get_num_bios(ti) : 0; + if (!num_bios) + return -EOPNOTSUPP; - /* - * Even though the device advertised support for this type of - * request, that does not mean every target supports it, and - * reconfiguration might also have changed that since the - * check was performed. - */ - num_bios = get_num_bios ? get_num_bios(ti) : 0; - if (!num_bios) - return -EOPNOTSUPP; + if (is_split_required && !is_split_required(ti)) + len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); + else + len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti)); - if (is_split_required && !is_split_required(ti)) - len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); - else - 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); + ci->sector += len; + ci->sector_count -= len; return 0; } -static int __send_discard(struct clone_info *ci) +static int __send_discard(struct clone_info *ci, struct dm_target *ti) { - return __send_changing_extent_only(ci, get_num_discard_bios, + return __send_changing_extent_only(ci, ti, get_num_discard_bios, is_split_required_for_discard); } -static int __send_write_same(struct clone_info *ci) +static int __send_write_same(struct clone_info *ci, struct dm_target *ti) { - return __send_changing_extent_only(ci, get_num_write_same_bios, NULL); + return __send_changing_extent_only(ci, ti, get_num_write_same_bios, NULL); } -static int __send_write_zeroes(struct clone_info *ci) +static int __send_write_zeroes(struct clone_info *ci, struct dm_target *ti) { - return __send_changing_extent_only(ci, get_num_write_zeroes_bios, NULL); + return __send_changing_extent_only(ci, ti, get_num_write_zeroes_bios, NULL); } /* @@ -1410,17 +1404,17 @@ static int __split_and_process_non_flush(struct clone_info *ci) unsigned len; int r; - if (unlikely(bio_op(bio) == REQ_OP_DISCARD)) - return __send_discard(ci); - else if (unlikely(bio_op(bio) == REQ_OP_WRITE_SAME)) - return __send_write_same(ci); - else if (unlikely(bio_op(bio) == REQ_OP_WRITE_ZEROES)) - return __send_write_zeroes(ci); - ti = dm_table_find_target(ci->map, ci->sector); if (!dm_target_is_valid(ti)) return -EIO; + if (unlikely(bio_op(bio) == REQ_OP_DISCARD)) + return __send_discard(ci, ti); + else if (unlikely(bio_op(bio) == REQ_OP_WRITE_SAME)) + return __send_write_same(ci, ti); + else if (unlikely(bio_op(bio) == REQ_OP_WRITE_ZEROES)) + return __send_write_zeroes(ci, ti); + if (bio_op(bio) == REQ_OP_ZONE_REPORT) len = ci->sector_count; else