[dpdk-dev] [PATCH v4 04/26] cryptodev: do not store pointer to op specific params

[Pablo de Lara <pablo.de.lara.guarch@intel.com>]

Instead of storing a pointer to operation specific parameters,
such as symmetric crypto parameters, use a zero-length array,
to mark that these parameters will be stored after the
generic crypto operation structure, which was already assumed
in the code, reducing the memory footprint of the crypto operation.

Besides, it is always expected to have rte_crypto_op
and rte_crypto_sym_op (the only operation specific parameters
structure right now) to be together, as they are initialized
as a single object in the crypto operation pool.

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Akhil Goyal <akhil.goyal@nxp.com>
Acked-by: Fiona Trahe <fiona.trahe@intel.com>
---
 doc/guides/rel_notes/release_17_08.rst | 2 ++
 examples/ipsec-secgw/ipsec.c           | 1 -
 lib/librte_cryptodev/rte_crypto.h      | 8 +-------
 3 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/doc/guides/rel_notes/release_17_08.rst b/doc/guides/rel_notes/release_17_08.rst
index 20f459e..6acbf35 100644
--- a/doc/guides/rel_notes/release_17_08.rst
+++ b/doc/guides/rel_notes/release_17_08.rst
@@ -155,6 +155,8 @@ API Changes
     ``rte_crypto_op_sess_type`` in ``rte_crypto_op`` have been modified to be
     uint8_t values.
   * Removed the field ``opaque_data`` from ``rte_crypto_op``.
+  * Pointer to ``rte_crypto_sym_op`` in ``rte_crypto_op`` has been replaced
+    with a zero length array.
 
 
 ABI Changes
diff --git a/examples/ipsec-secgw/ipsec.c b/examples/ipsec-secgw/ipsec.c
index edca5f0..126d79f 100644
--- a/examples/ipsec-secgw/ipsec.c
+++ b/examples/ipsec-secgw/ipsec.c
@@ -140,7 +140,6 @@ ipsec_enqueue(ipsec_xform_fn xform_func, struct ipsec_ctx *ipsec_ctx,
 		priv->cop.status = RTE_CRYPTO_OP_STATUS_NOT_PROCESSED;
 
 		rte_prefetch0(&priv->sym_cop);
-		priv->cop.sym = &priv->sym_cop;
 
 		if ((unlikely(sa->crypto_session == NULL)) &&
 				create_session(ipsec_ctx, sa)) {
diff --git a/lib/librte_cryptodev/rte_crypto.h b/lib/librte_cryptodev/rte_crypto.h
index c2677fa..85716a6 100644
--- a/lib/librte_cryptodev/rte_crypto.h
+++ b/lib/librte_cryptodev/rte_crypto.h
@@ -124,7 +124,7 @@ struct rte_crypto_op {
 
 	RTE_STD_C11
 	union {
-		struct rte_crypto_sym_op *sym;
+		struct rte_crypto_sym_op sym[0];
 		/**< Symmetric operation parameters */
 	}; /**< operation specific parameters */
 } __rte_cache_aligned;
@@ -144,12 +144,6 @@ __rte_crypto_op_reset(struct rte_crypto_op *op, enum rte_crypto_op_type type)
 
 	switch (type) {
 	case RTE_CRYPTO_OP_TYPE_SYMMETRIC:
-		/** Symmetric operation structure starts after the end of the
-		 * rte_crypto_op structure.
-		 */
-		op->sym = (struct rte_crypto_sym_op *)(op + 1);
-		op->type = type;
-
 		__rte_crypto_sym_op_reset(op->sym);
 		break;
 	default:
-- 
2.9.4