Commit f1445032 authored by Mikulas Patocka's avatar Mikulas Patocka Committed by Mike Snitzer
Browse files

dm: shortcut the calls to linear_map and stripe_map 



Shortcut the calls to linear_map and stripe_map, so that they don't suffer
the overhead of retpolines used for indirect calls.

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@kernel.org>
parent 3da5d2de

drivers/md/dm-linear.c

+1 −1
Original line number Diff line number Diff line
@@ -85,7 +85,7 @@ static sector_t linear_map_sector(struct dm_target *ti, sector_t bi_sector) 
	return lc->start + dm_target_offset(ti, bi_sector);

}



static int linear_map(struct dm_target *ti, struct bio *bio)

int linear_map(struct dm_target *ti, struct bio *bio)

{

	struct linear_c *lc = ti->private;

drivers/md/dm-stripe.c

+1 −1
Original line number Diff line number Diff line
@@ -268,7 +268,7 @@ static int stripe_map_range(struct stripe_c *sc, struct bio *bio, 
	return DM_MAPIO_SUBMITTED;

}



static int stripe_map(struct dm_target *ti, struct bio *bio)

int stripe_map(struct dm_target *ti, struct bio *bio)

{

	struct stripe_c *sc = ti->private;

	uint32_t stripe;

drivers/md/dm.c

+9 −2
Original line number Diff line number Diff line
@@ -1423,10 +1423,17 @@ static void __map_bio(struct bio *clone) 
		 */

		if (unlikely(dm_emulate_zone_append(md)))

			r = dm_zone_map_bio(tio);

		else

			goto do_map;

	} else {

do_map:

		if (likely(ti->type->map == linear_map))

			r = linear_map(ti, clone);

		else if (ti->type->map == stripe_map)

			r = stripe_map(ti, clone);

		else

			r = ti->type->map(ti, clone);

	} else

		r = ti->type->map(ti, clone);

	}



	switch (r) {

	case DM_MAPIO_SUBMITTED:

drivers/md/dm.h

+2 −0
Original line number Diff line number Diff line
@@ -188,9 +188,11 @@ void dm_kobject_release(struct kobject *kobj); 
/*

 * Targets for linear and striped mappings

 */

int linear_map(struct dm_target *ti, struct bio *bio);

int dm_linear_init(void);

void dm_linear_exit(void);



int stripe_map(struct dm_target *ti, struct bio *bio);

int dm_stripe_init(void);

void dm_stripe_exit(void);