[dm-devel] [PATCH 02/11] nbd: don't set the discard_alignment queue limit

Christoph Hellwig hch at lst.de
Mon Apr 18 04:53:05 UTC 2022


The discard_alignment queue limit is named a bit misleading means the
offset into the block device at which the discard granularity starts.
Setting it to the discard granularity as done by nbd is mostly harmless
but also useless.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/block/nbd.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 4729aef8c6462..102597a4277b9 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -333,7 +333,6 @@ static int nbd_set_size(struct nbd_device *nbd, loff_t bytesize,
 
 	if (nbd->config->flags & NBD_FLAG_SEND_TRIM) {
 		nbd->disk->queue->limits.discard_granularity = blksize;
-		nbd->disk->queue->limits.discard_alignment = blksize;
 		blk_queue_max_discard_sectors(nbd->disk->queue, UINT_MAX);
 	}
 	blk_queue_logical_block_size(nbd->disk->queue, blksize);
@@ -1316,7 +1315,6 @@ static void nbd_config_put(struct nbd_device *nbd)
 
 		nbd->tag_set.timeout = 0;
 		nbd->disk->queue->limits.discard_granularity = 0;
-		nbd->disk->queue->limits.discard_alignment = 0;
 		blk_queue_max_discard_sectors(nbd->disk->queue, 0);
 
 		mutex_unlock(&nbd->config_lock);
@@ -1781,7 +1779,6 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
 	blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
 	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, disk->queue);
 	disk->queue->limits.discard_granularity = 0;
-	disk->queue->limits.discard_alignment = 0;
 	blk_queue_max_discard_sectors(disk->queue, 0);
 	blk_queue_max_segment_size(disk->queue, UINT_MAX);
 	blk_queue_max_segments(disk->queue, USHRT_MAX);
-- 
2.30.2



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