Current the discard granularity defaults to 0 and must be initialized by any driver that wants to support discard. Default to the sector size instead, which is the smallest possible value, and a very useful default. Signed-off-by: Christoph Hellwig <hch@xxxxxx> --- block/blk-settings.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/block/blk-settings.c b/block/blk-settings.c index ba6e0e97118c08..d993d20dab3c6d 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -48,7 +48,7 @@ void blk_set_default_limits(struct queue_limits *lim) lim->max_discard_sectors = 0; lim->max_hw_discard_sectors = 0; lim->max_secure_erase_sectors = 0; - lim->discard_granularity = 0; + lim->discard_granularity = 512; lim->discard_alignment = 0; lim->discard_misaligned = 0; lim->logical_block_size = lim->physical_block_size = lim->io_min = 512; @@ -309,6 +309,9 @@ void blk_queue_logical_block_size(struct request_queue *q, unsigned int size) limits->logical_block_size = size; + if (limits->discard_granularity < limits->logical_block_size) + limits->discard_granularity = limits->logical_block_size; + if (limits->physical_block_size < size) limits->physical_block_size = size; -- 2.39.2