Commit 21acdf45 authored Dec 21, 2017 by Ilya Dryomov

rbd: set max_segments to USHRT_MAX



Commit d3834fef ("rbd: bump queue_max_segments") bumped
max_segments (unsigned short) to max_hw_sectors (unsigned int).
max_hw_sectors is set to the number of 512-byte sectors in an object
and overflows unsigned short for 32M (largest possible) objects, making
the block layer resort to handing us single segment (i.e. single page
or even smaller) bios in that case.

Cc: stable@vger.kernel.org
Fixes: d3834fef ("rbd: bump queue_max_segments")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>

parent edd8ca80

drivers/block/rbd.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -4387,7 +4387,7 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
		segment_size = rbd_obj_bytes(&rbd_dev->header);
		blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
		q->limits.max_sectors = queue_max_hw_sectors(q);
		blk_queue_max_segments(q, segment_size / SECTOR_SIZE);
		blk_queue_max_segments(q, USHRT_MAX);
		blk_queue_max_segment_size(q, segment_size);
		blk_queue_io_min(q, segment_size);
		blk_queue_io_opt(q, segment_size);

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