From 23c47d2ada9f96731492a67b28c0072715075baa Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Wed, 15 Nov 2017 17:33:00 -0800 Subject: bdi: introduce BDI_CAP_SYNCHRONOUS_IO As discussed at https://lkml.kernel.org/r/<20170728165604.10455-1-ross.zwisler@linux.intel.com> someday we will remove rw_page(). If so, we need something to detect such super-fast storage on which synchronous IO operations like the current rw_page are always a win. Introduces BDI_CAP_SYNCHRONOUS_IO to indicate such devices. With it, we could use various optimization techniques. Link: http://lkml.kernel.org/r/1505886205-9671-3-git-send-email-minchan@kernel.org Signed-off-by: Minchan Kim Cc: Christoph Hellwig Cc: Dan Williams Cc: Ross Zwisler Cc: Hugh Dickins Cc: Ilya Dryomov Cc: Jens Axboe Cc: Sergey Senozhatsky Cc: Huang Ying Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/zram/zram_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/block/zram/zram_drv.c') diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index d95bb8ce5092..88564222f473 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1558,7 +1558,7 @@ static int zram_add(void) blk_queue_max_write_zeroes_sectors(zram->disk->queue, UINT_MAX); zram->disk->queue->backing_dev_info->capabilities |= - BDI_CAP_STABLE_WRITES; + (BDI_CAP_STABLE_WRITES | BDI_CAP_SYNCHRONOUS_IO); add_disk(zram->disk); ret = sysfs_create_group(&disk_to_dev(zram->disk)->kobj, -- cgit v1.2.3