Commit 5eed69ff authored Sep 19, 2014 by Dwight Engen Committed by David S. Miller Sep 30, 2014

sunvdc: limit each sg segment to a page



ldc_map_sg() could fail its check that the number of pages referred to
by the sg scatterlist was <= the number of cookies.

This fixes the issue by doing a similar thing to the xen-blkfront driver,
ensuring that the scatterlist will only ever contain a segment count <=
port->ring_cookies, and each segment will be page aligned, and <= page
size. This ensures that the scatterlist is always mappable.

Orabug: 19347817
OraBZ: 15945

Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent de5b73f0

drivers/block/sunvdc.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -747,6 +747,10 @@ static int probe_disk(struct vdc_port *port)

		port->disk = g;

		/* Each segment in a request is up to an aligned page in size. */
		blk_queue_segment_boundary(q, PAGE_SIZE - 1);
		blk_queue_max_segment_size(q, PAGE_SIZE);

		blk_queue_max_segments(q, port->ring_cookies);
		blk_queue_max_hw_sectors(q, port->max_xfer_size);
		g->major = vdc_major;

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