md: raid 1 supports TRIM
This makes md raid 1 support TRIM.
If one disk supports discard and another not, or one has discard_zero_data and
another not, there could be inconsistent between data from such disks. But this
should not matter, discarded data is useless. This will add extra copy in rebuild
though.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 611b5f7..05c557e 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -781,7 +781,12 @@
while (bio) { /* submit pending writes */
struct bio *next = bio->bi_next;
bio->bi_next = NULL;
- generic_make_request(bio);
+ if (unlikely((bio->bi_rw & REQ_DISCARD) &&
+ !blk_queue_discard(bdev_get_queue(bio->bi_bdev))))
+ /* Just ignore it */
+ bio_endio(bio, 0);
+ else
+ generic_make_request(bio);
bio = next;
}
} else
@@ -994,6 +999,8 @@
const int rw = bio_data_dir(bio);
const unsigned long do_sync = (bio->bi_rw & REQ_SYNC);
const unsigned long do_flush_fua = (bio->bi_rw & (REQ_FLUSH | REQ_FUA));
+ const unsigned long do_discard = (bio->bi_rw
+ & (REQ_DISCARD | REQ_SECURE));
struct md_rdev *blocked_rdev;
struct blk_plug_cb *cb;
struct raid1_plug_cb *plug = NULL;
@@ -1295,7 +1302,7 @@
conf->mirrors[i].rdev->data_offset);
mbio->bi_bdev = conf->mirrors[i].rdev->bdev;
mbio->bi_end_io = raid1_end_write_request;
- mbio->bi_rw = WRITE | do_flush_fua | do_sync;
+ mbio->bi_rw = WRITE | do_flush_fua | do_sync | do_discard;
mbio->bi_private = r1_bio;
atomic_inc(&r1_bio->remaining);
@@ -1549,6 +1556,8 @@
clear_bit(Unmerged, &rdev->flags);
}
md_integrity_add_rdev(rdev, mddev);
+ if (blk_queue_discard(bdev_get_queue(rdev->bdev)))
+ queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
print_conf(conf);
return err;
}
@@ -2783,6 +2792,7 @@
int i;
struct md_rdev *rdev;
int ret;
+ bool discard_supported = false;
if (mddev->level != 1) {
printk(KERN_ERR "md/raid1:%s: raid level not set to mirroring (%d)\n",
@@ -2812,6 +2822,8 @@
continue;
disk_stack_limits(mddev->gendisk, rdev->bdev,
rdev->data_offset << 9);
+ if (blk_queue_discard(bdev_get_queue(rdev->bdev)))
+ discard_supported = true;
}
mddev->degraded = 0;
@@ -2846,6 +2858,13 @@
mddev->queue->backing_dev_info.congested_fn = raid1_congested;
mddev->queue->backing_dev_info.congested_data = mddev;
blk_queue_merge_bvec(mddev->queue, raid1_mergeable_bvec);
+
+ if (discard_supported)
+ queue_flag_set_unlocked(QUEUE_FLAG_DISCARD,
+ mddev->queue);
+ else
+ queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD,
+ mddev->queue);
}
ret = md_integrity_register(mddev);
