dm: support non power of two target max_io_len
Remove the restriction that limits a target's specified maximum incoming
I/O size to be a power of 2.
Rename this setting from 'split_io' to the less-ambiguous 'max_io_len'.
Change it from sector_t to uint32_t, which is plenty big enough, and
introduce a wrapper function dm_set_target_max_io_len() to set it.
Use sector_div() to process it now that it is not necessarily a power of 2.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 6931bd1..992c9d4 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -165,7 +165,10 @@
else
sc->stripes_shift = __ffs(stripes);
- ti->split_io = chunk_size;
+ r = dm_set_target_max_io_len(ti, chunk_size);
+ if (r)
+ return r;
+
ti->num_flush_requests = stripes;
ti->num_discard_requests = stripes;