md: linear supports TRIM
This makes md linear support TRIM.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/linear.c b/drivers/md/linear.c
index 92c64d1..2101483 100644
--- a/drivers/md/linear.c
+++ b/drivers/md/linear.c
@@ -138,6 +138,7 @@
struct linear_conf *conf;
struct md_rdev *rdev;
int i, cnt;
+ bool discard_supported = false;
conf = kzalloc (sizeof (*conf) + raid_disks*sizeof(struct dev_info),
GFP_KERNEL);
@@ -171,6 +172,8 @@
conf->array_sectors += rdev->sectors;
cnt++;
+ if (blk_queue_discard(bdev_get_queue(rdev->bdev)))
+ discard_supported = true;
}
if (cnt != raid_disks) {
printk(KERN_ERR "md/linear:%s: not enough drives present. Aborting!\n",
@@ -178,6 +181,11 @@
goto out;
}
+ if (!discard_supported)
+ queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
+ else
+ queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
+
/*
* Here we calculate the device offsets.
*/
@@ -331,6 +339,14 @@
bio->bi_sector = bio->bi_sector - start_sector
+ tmp_dev->rdev->data_offset;
rcu_read_unlock();
+
+ if (unlikely((bio->bi_rw & REQ_DISCARD) &&
+ !blk_queue_discard(bdev_get_queue(bio->bi_bdev)))) {
+ /* Just ignore it */
+ bio_endio(bio, 0);
+ return;
+ }
+
generic_make_request(bio);
}