[PATCH 5/5] virtio-blk: Consider virtio_max_dma_size() for maximum segment size
From: Joerg Roedel <joro@8bytes.org>
Date: 2019-01-31 16:34:15
Also in:
linux-iommu, lkml
Subsystem:
block layer, the rest, virtio block and scsi drivers, virtio core · Maintainers:
Jens Axboe, Linus Torvalds, "Michael S. Tsirkin", Jason Wang
From: Joerg Roedel <redacted> Segments can't be larger than the maximum DMA mapping size supported on the platform. Take that into account when setting the maximum segment size for a block device. Reviewed-by: Konrad Rzeszutek Wilk <redacted> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Joerg Roedel <redacted> --- drivers/block/virtio_blk.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index b16a887bbd02..4bc083b7c9b5 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c@@ -723,7 +723,7 @@ static int virtblk_probe(struct virtio_device *vdev) struct request_queue *q; int err, index; - u32 v, blk_size, sg_elems, opt_io_size; + u32 v, blk_size, max_size, sg_elems, opt_io_size; u16 min_io_size; u8 physical_block_exp, alignment_offset;
@@ -826,14 +826,16 @@ static int virtblk_probe(struct virtio_device *vdev) /* No real sector limit. */ blk_queue_max_hw_sectors(q, -1U); + max_size = virtio_max_dma_size(vdev); + /* Host can optionally specify maximum segment size and number of * segments. */ err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SIZE_MAX, struct virtio_blk_config, size_max, &v); if (!err) - blk_queue_max_segment_size(q, v); - else - blk_queue_max_segment_size(q, -1U); + max_size = min(max_size, v); + + blk_queue_max_segment_size(q, max_size); /* Host can optionally specify the block size of the device */ err = virtio_cread_feature(vdev, VIRTIO_BLK_F_BLK_SIZE,
--
2.17.1