Commit d41d75fe authored by Giovanni Cabiddu's avatar Giovanni Cabiddu Committed by Herbert Xu
Browse files

crypto: qat - fix DMA direction for compression on GEN2 devices 



QAT devices perform an additional integrity check during compression by
decompressing the output. Starting from QAT GEN4, this verification is
done in-line by the hardware. However, on GEN2 devices, the hardware
reads back the compressed output from the destination buffer and performs
a decompression operation using it as the source.

In the current QAT driver, destination buffers are always marked as
write-only. This is incorrect for QAT GEN2 compression, where the buffer
is also read during verification. Since commit 6f5dc765
("iommu/vt-d: Restore WO permissions on second-level paging entries"),
merged in v6.16-rc1, write-only permissions are strictly enforced, leading
to DMAR errors when using QAT GEN2 devices for compression, if VT-d is
enabled.

Mark the destination buffers as DMA_BIDIRECTIONAL. This ensures
compatibility with GEN2 devices, even though it is not required for
QAT GEN4 and later.

Signed-off-by: default avatarGiovanni Cabiddu <giovanni.cabiddu@intel.com>
Fixes: cf5bb835 ("crypto: qat - fix DMA transfer direction")
Reviewed-by: default avatarAhsan Atta <ahsan.atta@intel.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 4fec76bc

drivers/crypto/intel/qat/qat_common/qat_bl.c

+3 −3
Original line number Diff line number Diff line
@@ -38,7 +38,7 @@ void qat_bl_free_bufl(struct adf_accel_dev *accel_dev, 
		for (i = 0; i < blout->num_mapped_bufs; i++) {

			dma_unmap_single(dev, blout->buffers[i].addr,

					 blout->buffers[i].len,

					 DMA_FROM_DEVICE);

					 DMA_BIDIRECTIONAL);

		}

		dma_unmap_single(dev, blpout, sz_out, DMA_TO_DEVICE);
@@ -162,7 +162,7 @@ static int __qat_bl_sgl_to_bufl(struct adf_accel_dev *accel_dev, 
			}

			buffers[y].addr = dma_map_single(dev, sg_virt(sg) + left,

							 sg->length - left,

							 DMA_FROM_DEVICE);

							 DMA_BIDIRECTIONAL);

			if (unlikely(dma_mapping_error(dev, buffers[y].addr)))

				goto err_out;

			buffers[y].len = sg->length;
@@ -204,7 +204,7 @@ static int __qat_bl_sgl_to_bufl(struct adf_accel_dev *accel_dev, 
		if (!dma_mapping_error(dev, buflout->buffers[i].addr))

			dma_unmap_single(dev, buflout->buffers[i].addr,

					 buflout->buffers[i].len,

					 DMA_FROM_DEVICE);

					 DMA_BIDIRECTIONAL);

	}



	if (!buf->sgl_dst_valid)

drivers/crypto/intel/qat/qat_common/qat_compression.c

+2 −2
Original line number Diff line number Diff line
@@ -204,7 +204,7 @@ static int qat_compression_alloc_dc_data(struct adf_accel_dev *accel_dev) 
	if (!obuff)

		goto err;



	obuff_p = dma_map_single(dev, obuff, ovf_buff_sz, DMA_FROM_DEVICE);

	obuff_p = dma_map_single(dev, obuff, ovf_buff_sz, DMA_BIDIRECTIONAL);

	if (unlikely(dma_mapping_error(dev, obuff_p)))

		goto err;
@@ -232,7 +232,7 @@ static void qat_free_dc_data(struct adf_accel_dev *accel_dev) 
		return;



	dma_unmap_single(dev, dc_data->ovf_buff_p, dc_data->ovf_buff_sz,

			 DMA_FROM_DEVICE);

			 DMA_BIDIRECTIONAL);

	kfree_sensitive(dc_data->ovf_buff);

	kfree(dc_data);

	accel_dev->dc_data = NULL;