diff options
| -rw-r--r-- | drivers/block/drbd/drbd_nl.c | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index 9135001a8e57..0326b7322ceb 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -1295,30 +1295,39 @@ static void fixup_discard_support(struct drbd_device *device, struct request_que } } +/* This is the workaround for "bio would need to, but cannot, be split" */ +static unsigned int drbd_backing_dev_max_segments(struct drbd_device *device) +{ + unsigned int max_segments; + + rcu_read_lock(); + max_segments = rcu_dereference(device->ldev->disk_conf)->max_bio_bvecs; + rcu_read_unlock(); + + if (!max_segments) + return BLK_MAX_SEGMENTS; + return max_segments; +} + static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backing_dev *bdev, unsigned int max_bio_size, struct o_qlim *o) { struct request_queue * const q = device->rq_queue; unsigned int max_hw_sectors = max_bio_size >> 9; - unsigned int max_segments = 0; + unsigned int max_segments = BLK_MAX_SEGMENTS; struct request_queue *b = NULL; - struct disk_conf *dc; if (bdev) { b = bdev->backing_bdev->bd_disk->queue; max_hw_sectors = min(queue_max_hw_sectors(b), max_bio_size >> 9); - rcu_read_lock(); - dc = rcu_dereference(device->ldev->disk_conf); - max_segments = dc->max_bio_bvecs; - rcu_read_unlock(); + max_segments = drbd_backing_dev_max_segments(device); blk_set_stacking_limits(&q->limits); } blk_queue_max_hw_sectors(q, max_hw_sectors); - /* This is the workaround for "bio would need to, but cannot, be split" */ - blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS); + blk_queue_max_segments(q, max_segments); blk_queue_segment_boundary(q, PAGE_SIZE-1); decide_on_discard_support(device, bdev); |