block: Fix null_blk_zoned creation failure with small number of zones

null_blk_zoned creation fails if the number of zones specified is equal to or is
smaller than 64 due to a memory allocation failure in blk_alloc_zones(). With
such a small number of zones, the required memory size for all zones descriptors
fits in a single page, and the page order for alloc_pages_node() is zero. Allow
this value in blk_alloc_zones() for the allocation to succeed.

Fixes: bf50545696 "block: Introduce blk_revalidate_disk_zones()"
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Shin'ichiro Kawasaki 2018-12-11 21:08:26 +09:00 committed by Jens Axboe
parent a538e3ff9d
commit 927b6b2d69

View File

@ -378,7 +378,7 @@ static struct blk_zone *blk_alloc_zones(int node, unsigned int *nr_zones)
struct page *page;
int order;
for (order = get_order(size); order > 0; order--) {
for (order = get_order(size); order >= 0; order--) {
page = alloc_pages_node(node, GFP_NOIO | __GFP_ZERO, order);
if (page) {
*nr_zones = min_t(unsigned int, *nr_zones,