drbd: properly use max_hw_sectors to limit the our bio size
To ease tracking of bios in some hash tables, we want it to
not cross certain boundaries (128k, used to be 32k).
We limit the maximum bio size using queue parameters.
Historically some defines and variables we use there have been named
max_segment_size, which was misguided. Rename them to max_bio_size,
and use [blk_]queue_max_hw_sectors where appropriate.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index dad5598..9e27d82 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -765,22 +765,21 @@
return 0;
}
-void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int max_seg_s) __must_hold(local)
+void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int max_bio_size) __must_hold(local)
{
struct request_queue * const q = mdev->rq_queue;
struct request_queue * const b = mdev->ldev->backing_bdev->bd_disk->queue;
int max_segments = mdev->ldev->dc.max_bio_bvecs;
+ int max_hw_sectors = min(queue_max_hw_sectors(b), max_bio_size >> 9);
- max_seg_s = min(queue_max_sectors(b) * queue_logical_block_size(b), max_seg_s);
-
- blk_queue_max_hw_sectors(q, max_seg_s >> 9);
- blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS);
- blk_queue_max_segment_size(q, max_seg_s);
blk_queue_logical_block_size(q, 512);
- blk_queue_segment_boundary(q, PAGE_SIZE-1);
- blk_stack_limits(&q->limits, &b->limits, 0);
+ 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_segment_boundary(q, PAGE_CACHE_SIZE-1);
+ blk_queue_stack_limits(q, b);
- dev_info(DEV, "max_segment_size ( = BIO size ) = %u\n", queue_max_segment_size(q));
+ dev_info(DEV, "max BIO size = %u\n", queue_max_hw_sectors(q) << 9);
if (q->backing_dev_info.ra_pages != b->backing_dev_info.ra_pages) {
dev_info(DEV, "Adjusting my ra_pages to backing device's (%lu -> %lu)\n",
@@ -858,7 +857,7 @@
struct block_device *bdev;
struct lru_cache *resync_lru = NULL;
union drbd_state ns, os;
- unsigned int max_seg_s;
+ unsigned int max_bio_size;
int rv;
int cp_discovered = 0;
int logical_block_size;
@@ -1109,20 +1108,20 @@
mdev->read_cnt = 0;
mdev->writ_cnt = 0;
- max_seg_s = DRBD_MAX_SEGMENT_SIZE;
+ max_bio_size = DRBD_MAX_BIO_SIZE;
if (mdev->state.conn == C_CONNECTED) {
/* We are Primary, Connected, and now attach a new local
* backing store. We must not increase the user visible maximum
* bio size on this device to something the peer may not be
* able to handle. */
if (mdev->agreed_pro_version < 94)
- max_seg_s = queue_max_segment_size(mdev->rq_queue);
+ max_bio_size = queue_max_hw_sectors(mdev->rq_queue) << 9;
else if (mdev->agreed_pro_version == 94)
- max_seg_s = DRBD_MAX_SIZE_H80_PACKET;
+ max_bio_size = DRBD_MAX_SIZE_H80_PACKET;
/* else: drbd 8.3.9 and later, stay with default */
}
- drbd_setup_queue_param(mdev, max_seg_s);
+ drbd_setup_queue_param(mdev, max_bio_size);
/* If I am currently not R_PRIMARY,
* but meta data primary indicator is set,