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 --- drivers/md/raid1.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) Index: linux/drivers/md/raid1.c =================================================================== --- linux.orig/drivers/md/raid1.c 2012-03-12 10:09:42.426612652 +0800 +++ linux/drivers/md/raid1.c 2012-03-12 10:16:50.276610783 +0800 @@ -673,7 +673,12 @@ static void flush_pending_writes(struct 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 @@ -835,6 +840,7 @@ static void make_request(struct mddev *m 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; int plugged; int first_clone; @@ -1135,7 +1141,7 @@ read_again: 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); @@ -1371,6 +1377,8 @@ static int raid1_add_disk(struct mddev * } } 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; } @@ -2585,6 +2593,7 @@ static int run(struct mddev *mddev) struct r1conf *conf; int i; struct md_rdev *rdev; + bool discard_supported = false; if (mddev->level != 1) { printk(KERN_ERR "md/raid1:%s: raid level not set to mirroring (%d)\n", @@ -2623,8 +2632,16 @@ static int run(struct mddev *mddev) blk_queue_segment_boundary(mddev->queue, PAGE_CACHE_SIZE - 1); } + + if (blk_queue_discard(bdev_get_queue(rdev->bdev))) + discard_supported = true; } + if (discard_supported) + queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); + else + queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); + mddev->degraded = 0; for (i=0; i < conf->raid_disks; i++) if (conf->mirrors[i].rdev == NULL || -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/