dm stripe: expose correct io hints
Set sensible I/O hints for striped DM devices in the topology
infrastructure added for 2.6.31 for userspace tools to
obtain via sysfs.
Add .io_hints to 'struct target_type' to allow the I/O hints portion
(io_min and io_opt) of the 'struct queue_limits' to be set by each
target and implement this for dm-stripe.
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 4e0e593..3e563d2 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -329,9 +329,19 @@
return ret;
}
+static void stripe_io_hints(struct dm_target *ti,
+ struct queue_limits *limits)
+{
+ struct stripe_c *sc = ti->private;
+ unsigned chunk_size = (sc->chunk_mask + 1) << 9;
+
+ blk_limits_io_min(limits, chunk_size);
+ limits->io_opt = chunk_size * sc->stripes;
+}
+
static struct target_type stripe_target = {
.name = "striped",
- .version = {1, 2, 0},
+ .version = {1, 3, 0},
.module = THIS_MODULE,
.ctr = stripe_ctr,
.dtr = stripe_dtr,
@@ -339,6 +349,7 @@
.end_io = stripe_end_io,
.status = stripe_status,
.iterate_devices = stripe_iterate_devices,
+ .io_hints = stripe_io_hints,
};
int __init dm_stripe_init(void)