[PATCH 29/60] dm: limit the max bio size as BIO_SP_MAX_SECTORS << SECTOR_SHIFT
From: Ming Lei <tom.leiming@gmail.com>
Date: 2016-10-29 08:08:28
Also in:
dm-devel, linux-block, linux-fsdevel, lkml
Subsystem:
device-mapper (lvm), the rest · Maintainers:
Alasdair Kergon, Mike Snitzer, Mikulas Patocka, Benjamin Marzinski, Linus Torvalds
For BIO based DM, some targets aren't ready for dealing with bigger incoming bio than 1Mbyte, such as crypt and log write targets. Signed-off-by: Ming Lei <tom.leiming@gmail.com> --- drivers/md/dm.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index ef7bf1dd6900..ce454c6c1a4e 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c@@ -899,7 +899,16 @@ int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) return -EINVAL; } - ti->max_io_len = (uint32_t) len; + /* + * BIO based queue uses its own splitting. When multipage bvecs + * is switched on, size of the incoming bio may be too big to + * be handled in some targets, such as crypt and log write. + * + * When these targets are ready for the big bio, we can remove + * the limit. + */ + ti->max_io_len = min_t(uint32_t, len, + BIO_SP_MAX_SECTORS << SECTOR_SHIFT); return 0; }
--
2.7.4