[dpdk-dev] [PATCH v5 2/5] ethdev: support flow elements with variable length

[Viacheslav Ovsiienko <viacheslavo@nvidia.com>]

From: Gregory Etelson <getelson@nvidia.com>

RTE flow API provides RAW item type for packet patterns of variable
length. The RAW item structure has fixed size members that describe the
variable pattern length and methods to process it.

There is the new RTE Flow items with variable lengths coming - flex
item. In order to handle this item (and potentially other new ones
with variable pattern length) in RTE flow copy and conversion routines
the helper function is introduced.

Signed-off-by: Gregory Etelson <getelson@nvidia.com>
Reviewed-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>
Acked-by: Ori Kam <orika@nvidia.com>
---
 lib/ethdev/rte_flow.c | 81 ++++++++++++++++++++++++++++++++++++-------
 1 file changed, 68 insertions(+), 13 deletions(-)

diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c
index 8cb7a069c8..051781b440 100644
--- a/lib/ethdev/rte_flow.c
+++ b/lib/ethdev/rte_flow.c
@@ -30,13 +30,65 @@ uint64_t rte_flow_dynf_metadata_mask;
 struct rte_flow_desc_data {
 	const char *name;
 	size_t size;
+	size_t (*desc_fn)(void *dst, const void *src);
 };
 
+/**
+ *
+ * @param buf
+ * Destination memory.
+ * @param data
+ * Source memory
+ * @param size
+ * Requested copy size
+ * @param desc
+ * rte_flow_desc_item - for flow item conversion.
+ * rte_flow_desc_action - for flow action conversion.
+ * @param type
+ * Offset into the desc param or negative value for private flow elements.
+ */
+static inline size_t
+rte_flow_conv_copy(void *buf, const void *data, const size_t size,
+		   const struct rte_flow_desc_data *desc, int type)
+{
+	/**
+	 * Allow PMD private flow item
+	 */
+	size_t sz = type >= 0 ? desc[type].size : sizeof(void *);
+	if (buf == NULL || data == NULL)
+		return 0;
+	rte_memcpy(buf, data, (size > sz ? sz : size));
+	if (desc[type].desc_fn)
+		sz += desc[type].desc_fn(size > 0 ? buf : NULL, data);
+	return sz;
+}
+
+static size_t
+rte_flow_item_flex_conv(void *buf, const void *data)
+{
+	struct rte_flow_item_flex *dst = buf;
+	const struct rte_flow_item_flex *src = data;
+	if (buf) {
+		dst->pattern = rte_memcpy
+			((void *)((uintptr_t)(dst + 1)), src->pattern,
+			 src->length);
+	}
+	return src->length;
+}
+
 /** Generate flow_item[] entry. */
 #define MK_FLOW_ITEM(t, s) \
 	[RTE_FLOW_ITEM_TYPE_ ## t] = { \
 		.name = # t, \
-		.size = s, \
+		.size = s,               \
+		.desc_fn = NULL,\
+	}
+
+#define MK_FLOW_ITEM_FN(t, s, fn) \
+	[RTE_FLOW_ITEM_TYPE_ ## t] = {\
+		.name = # t,                 \
+		.size = s,                   \
+		.desc_fn = fn,               \
 	}
 
 /** Information about known flow pattern items. */
@@ -100,6 +152,8 @@ static const struct rte_flow_desc_data rte_flow_desc_item[] = {
 	MK_FLOW_ITEM(GENEVE_OPT, sizeof(struct rte_flow_item_geneve_opt)),
 	MK_FLOW_ITEM(INTEGRITY, sizeof(struct rte_flow_item_integrity)),
 	MK_FLOW_ITEM(CONNTRACK, sizeof(uint32_t)),
+	MK_FLOW_ITEM_FN(FLEX, sizeof(struct rte_flow_item_flex),
+			rte_flow_item_flex_conv),
 };
 
 /** Generate flow_action[] entry. */
@@ -107,8 +161,17 @@ static const struct rte_flow_desc_data rte_flow_desc_item[] = {
 	[RTE_FLOW_ACTION_TYPE_ ## t] = { \
 		.name = # t, \
 		.size = s, \
+		.desc_fn = NULL,\
+	}
+
+#define MK_FLOW_ACTION_FN(t, fn) \
+	[RTE_FLOW_ACTION_TYPE_ ## t] = { \
+		.name = # t, \
+		.size = 0, \
+		.desc_fn = fn,\
 	}
 
+
 /** Information about known flow actions. */
 static const struct rte_flow_desc_data rte_flow_desc_action[] = {
 	MK_FLOW_ACTION(END, 0),
@@ -527,12 +590,8 @@ rte_flow_conv_item_spec(void *buf, const size_t size,
 		}
 		break;
 	default:
-		/**
-		 * allow PMD private flow item
-		 */
-		off = (int)item->type >= 0 ?
-		      rte_flow_desc_item[item->type].size : sizeof(void *);
-		rte_memcpy(buf, data, (size > off ? off : size));
+		off = rte_flow_conv_copy(buf, data, size,
+					 rte_flow_desc_item, item->type);
 		break;
 	}
 	return off;
@@ -634,12 +693,8 @@ rte_flow_conv_action_conf(void *buf, const size_t size,
 		}
 		break;
 	default:
-		/**
-		 * allow PMD private flow action
-		 */
-		off = (int)action->type >= 0 ?
-		      rte_flow_desc_action[action->type].size : sizeof(void *);
-		rte_memcpy(buf, action->conf, (size > off ? off : size));
+		off = rte_flow_conv_copy(buf, action->conf, size,
+					 rte_flow_desc_action, action->type);
 		break;
 	}
 	return off;
-- 
2.18.1