+static int raid1_mergeable_bvec(struct request_queue *q,
+ struct bvec_merge_data *bvm,
+ struct bio_vec *biovec)
+{
+ struct mddev *mddev = q->queuedata;
+ struct r1conf *conf = mddev->private;
+ sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
+ int max = biovec->bv_len;
+
+ if (mddev->merge_check_needed) {
+ int disk;
+ rcu_read_lock();
+ for (disk = 0; disk < conf->raid_disks * 2; disk++) {
+ struct md_rdev *rdev = rcu_dereference(
+ conf->mirrors[disk].rdev);
+ if (rdev && !test_bit(Faulty, &rdev->flags)) {
+ struct request_queue *q =
+ bdev_get_queue(rdev->bdev);
+ if (q->merge_bvec_fn) {
+ bvm->bi_sector = sector +
+ rdev->data_offset;
+ bvm->bi_bdev = rdev->bdev;
+ max = min(max, q->merge_bvec_fn(
+ q, bvm, biovec));
+ }
+ }
+ }
+ rcu_read_unlock();
+ }
+ return max;
+
+}
+