On Wed, May 23, 2018 at 01:35:59PM -0400, Josef Bacik wrote:
> From: Josef Bacik <jbacik@xxxxxx>
>
> For some reason we had discard granularity set to 512 always even when
> discards were disabled. Fix this by having the default be 0, and then
> if we turn it on set the discard granularity to the blocksize.
>
> Signed-off-by: Josef Bacik <jbacik@xxxxxx>
> Reviewed-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
> ---
> drivers/block/nbd.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
> index 1147e4680c80..bdfbb2a7018c 100644
> --- a/drivers/block/nbd.c
> +++ b/drivers/block/nbd.c
> @@ -236,6 +236,10 @@ static void nbd_size_update(struct nbd_device *nbd)
> struct nbd_config *config = nbd->config;
> struct block_device *bdev = bdget_disk(nbd->disk, 0);
>
> + if (config->flags & NBD_FLAG_SEND_TRIM) {
> + nbd->disk->queue->limits.discard_granularity = config->blksize;
> + blk_queue_max_discard_sectors(nbd->disk->queue, UINT_MAX);
> + }
> blk_queue_logical_block_size(nbd->disk->queue, config->blksize);
> blk_queue_physical_block_size(nbd->disk->queue, config->blksize);
> set_capacity(nbd->disk, config->bytesize >> 9);
> @@ -1050,6 +1054,8 @@ static void nbd_config_put(struct nbd_device *nbd)
> nbd->config = NULL;
>
> nbd->tag_set.timeout = 0;
> + nbd->disk->queue->limits.discard_granularity = 0;
> + blk_queue_max_discard_sectors(nbd->disk->queue, UINT_MAX);
> blk_queue_flag_clear(QUEUE_FLAG_DISCARD, nbd->disk->queue);
>
> mutex_unlock(&nbd->config_lock);
> @@ -1502,8 +1508,8 @@ static int nbd_dev_add(int index)
> */
> blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
> blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, disk->queue);
> - disk->queue->limits.discard_granularity = 512;
> - blk_queue_max_discard_sectors(disk->queue, UINT_MAX);
> + disk->queue->limits.discard_granularity = 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);
> blk_queue_max_hw_sectors(disk->queue, 65536);
Could you add a blktest for this? (And also respond to the comment on
https://github.com/osandov/blktests/pull/18).
Thanks!
