Re: [PATCH] cryptodev: fix ABI breakage

["Gujjar, Abhinandan S" <abhinandan.gujjar@intel.com>]

> -----Original Message-----
> From: De Lara Guarch, Pablo
> Sent: Wednesday, June 13, 2018 3:07 PM
> To: Doherty, Declan <declan.doherty@intel.com>; Gujjar, Abhinandan S
> <abhinandan.gujjar@intel.com>
> Cc: dev@dpdk.org; De Lara Guarch, Pablo <pablo.de.lara.guarch@intel.com>;
> stable@dpdk.org
> Subject: [PATCH] cryptodev: fix ABI breakage
> 
> In 17.08, the crypto operation was restructured, and some reserved bytes (5)
> were added  to have the mempool pointer aligned to 64 bits, since the structure
> is expected to be aligned to 64 bits, allowing future additions with no ABI
> breakage needed.
> 
> In 18.05, a new 2-byte field was added, so the reserved bytes were reduced to 3.
> However, this field was added after the first 3 bytes of the structure, causing it
> to be placed in an offset of 4 bytes, and therefore, forcing the mempool pointer
> to be placed after 16 bytes, instead of a 8 bytes, causing unintentionally the ABI
> breakage.
> 
> This commit fixes the breakage, by swapping the reserved bytes and the
> private_data_offset field, so the latter is aligned to 2 bytes and the offset of the
> mempool pointer returns to its original offset,
> 8 bytes.
> 
> Fixes: 54c836846603 ("cryptodev: set private data for session-less mode")
> Cc: stable@dpdk.org
> 
> Reported-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
> ---
>  lib/librte_cryptodev/rte_crypto.h | 51 +++++++++++++++++++------------
>  1 file changed, 31 insertions(+), 20 deletions(-)
> 
> diff --git a/lib/librte_cryptodev/rte_crypto.h b/lib/librte_cryptodev/rte_crypto.h
> index 25404264b..a16be656d 100644
> --- a/lib/librte_cryptodev/rte_crypto.h
> +++ b/lib/librte_cryptodev/rte_crypto.h
> @@ -73,26 +73,37 @@ enum rte_crypto_op_sess_type {
>   * rte_cryptodev_enqueue_burst() / rte_cryptodev_dequeue_burst() .
>   */
>  struct rte_crypto_op {
> -	uint8_t type;
> -	/**< operation type */
> -	uint8_t status;
> -	/**<
> -	 * operation status - this is reset to
> -	 * RTE_CRYPTO_OP_STATUS_NOT_PROCESSED on allocation from
> mempool and
> -	 * will be set to RTE_CRYPTO_OP_STATUS_SUCCESS after crypto
> operation
> -	 * is successfully processed by a crypto PMD
> -	 */
> -	uint8_t sess_type;
> -	/**< operation session type */
> -	uint16_t private_data_offset;
> -	/**< Offset to indicate start of private data (if any). The offset
> -	 * is counted from the start of the rte_crypto_op including IV.
> -	 * The private data may be used by the application to store
> -	 * information which should remain untouched in the library/driver
> -	 */
> -
> -	uint8_t reserved[3];
> -	/**< Reserved bytes to fill 64 bits for future additions */
> +	__extension__
> +	union {
> +		uint64_t raw;
> +		__extension__
> +		struct {
> +			uint8_t type;
> +			/**< operation type */
> +			uint8_t status;
> +			/**<
> +			 * operation status - this is reset to
> +			 * RTE_CRYPTO_OP_STATUS_NOT_PROCESSED on
> allocation
> +			 * from mempool and will be set to
> +			 * RTE_CRYPTO_OP_STATUS_SUCCESS after crypto
> operation
> +			 * is successfully processed by a crypto PMD
> +			 */
> +			uint8_t sess_type;
> +			/**< operation session type */
> +			uint8_t reserved[3];
> +			/**< Reserved bytes to fill 64 bits for
> +			 * future additions
> +			 */
> +			uint16_t private_data_offset;
> +			/**< Offset to indicate start of private data (if any).
> +			 * The offset is counted from the start of the
> +			 * rte_crypto_op including IV.
> +			 * The private data may be used by the application
> +			 * to store information which should remain untouched
> +			 * in the library/driver
> +			 */
> +		};
> +	};
>  	struct rte_mempool *mempool;
>  	/**< crypto operation mempool which operation is allocated from */
> 
> --

Acked-by: Abhinandan Gujjar <Abhinandan.gujjar@intel.com>

> 2.17.0