From ec3c8ca156750022272b073352d8cca75057cd79 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Wed, 13 Feb 2019 18:42:13 +0800 Subject: [PATCH] dm: do not allow readahead to limit IO size mainline inclusion from mainline-5.0-rc1 commit c6d6e9b0f6b4201c77f2cea3964dd122697e3543 category: bugfix bugzilla: 5879 CVE: NA --------------------------- Update DM to set the bdi's io_pages. This fixes reads to be capped at the device's max request size (even if user's read IO exceeds the established readahead setting). Conflicts: drivers/md/dm-table.c Fixes: 9491ae4a ("mm: don't cap request size based on read-ahead setting") Cc: stable@vger.kernel.org Reviewed-by: Jens Axboe Signed-off-by: Jaegeuk Kim Signed-off-by: Mike Snitzer Signed-off-by: Yufen Yu Reviewed-by: Jason Yan Signed-off-by: Yang Yingliang --- drivers/md/dm-table.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 3d0e2c198f06..f54ba99c089f 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -1937,6 +1937,9 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, */ if (blk_queue_add_random(q) && dm_table_all_devices_attribute(t, device_is_not_random)) blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q); + + /* Allow reads to exceed readahead limits */ + q->backing_dev_info->io_pages = limits->max_sectors >> (PAGE_SHIFT - 9); } unsigned int dm_table_get_num_targets(struct dm_table *t) -- GitLab