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 6f5dc7658094
("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: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Fixes: cf5bb835b7c8 ("crypto: qat - fix DMA transfer direction")
Reviewed-by: Ahsan Atta <ahsan.atta@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/intel/qat/qat_common/qat_bl.c b/drivers/crypto/intel/qat/qat_common/qat_bl.c
index 5e4dad4693caad46ecfa1092b6546a822133e051..9b2338f58d97c43143d889ac8831db92d37ac446 100644 (file)
--- a/drivers/crypto/intel/qat/qat_common/qat_bl.c
+++ b/drivers/crypto/intel/qat/qat_common/qat_bl.c
@@ -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 @@ err_out:
                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)

diff --git a/drivers/crypto/intel/qat/qat_common/qat_compression.c b/drivers/crypto/intel/qat/qat_common/qat_compression.c
index 0a77ca65c8d482c6bd27aa69c6473caf546273fb..53a4db5507ec2802ebb2b5b614b7aece9b3e9bd9 100644 (file)
--- a/drivers/crypto/intel/qat/qat_common/qat_compression.c
+++ b/drivers/crypto/intel/qat/qat_common/qat_compression.c
@@ -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;