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:Giovanni Cabiddu <giovanni.cabiddu@intel.com> Fixes: cf5bb835 ("crypto: qat - fix DMA transfer direction") Reviewed-by:
Ahsan Atta <ahsan.atta@intel.com> Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au>
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