[dpdk-dev] [PATCH v2 12/15] ethdev: update behavior of VF/PF in flow API

[Adrien Mazarguil <adrien.mazarguil@6wind.com>]

Contrary to all other pattern items, these are inconsistently documented as
affecting traffic instead of simply matching its origin, without provision
for the latter.

This commit clarifies documentation and updates PMDs since the original
behavior now has to be explicitly requested using the new transfer
attribute.

It breaks ABI compatibility for the following public functions:

- rte_flow_create()
- rte_flow_validate()

Impacted PMDs are bnxt and i40e, for which the VF pattern item is now only
supported when a transfer attribute is also present.

Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
Cc: Ajit Khaparde <ajit.khaparde@broadcom.com>
Cc: Somnath Kotur <somnath.kotur@broadcom.com>
Cc: Beilei Xing <beilei.xing@intel.com>
Cc: Qi Zhang <qi.z.zhang@intel.com>
---
 app/test-pmd/cmdline_flow.c                 | 12 +++---
 doc/guides/prog_guide/rte_flow.rst          | 36 +++++++++---------
 doc/guides/testpmd_app_ug/testpmd_funcs.rst | 12 +++---
 drivers/net/bnxt/bnxt_filter.c              | 22 ++++++-----
 drivers/net/i40e/i40e_flow.c                | 23 +++++++-----
 lib/librte_ether/rte_flow.h                 | 47 ++++++++++--------------
 6 files changed, 77 insertions(+), 75 deletions(-)

diff --git a/app/test-pmd/cmdline_flow.c b/app/test-pmd/cmdline_flow.c
index 122e9d50b..741d66b22 100644
--- a/app/test-pmd/cmdline_flow.c
+++ b/app/test-pmd/cmdline_flow.c
@@ -1041,21 +1041,21 @@ static const struct token token_list[] = {
 	},
 	[ITEM_PF] = {
 		.name = "pf",
-		.help = "match packets addressed to the physical function",
+		.help = "match traffic from/to the physical function",
 		.priv = PRIV_ITEM(PF, 0),
 		.next = NEXT(NEXT_ENTRY(ITEM_NEXT)),
 		.call = parse_vc,
 	},
 	[ITEM_VF] = {
 		.name = "vf",
-		.help = "match packets addressed to a virtual function ID",
+		.help = "match traffic from/to a virtual function ID",
 		.priv = PRIV_ITEM(VF, sizeof(struct rte_flow_item_vf)),
 		.next = NEXT(item_vf),
 		.call = parse_vc,
 	},
 	[ITEM_VF_ID] = {
 		.name = "id",
-		.help = "destination VF ID",
+		.help = "VF ID",
 		.next = NEXT(item_vf, NEXT_ENTRY(UNSIGNED), item_param),
 		.args = ARGS(ARGS_ENTRY(struct rte_flow_item_vf, id)),
 	},
@@ -1686,14 +1686,14 @@ static const struct token token_list[] = {
 	},
 	[ACTION_PF] = {
 		.name = "pf",
-		.help = "redirect packets to physical device function",
+		.help = "direct traffic to physical function",
 		.priv = PRIV_ACTION(PF, 0),
 		.next = NEXT(NEXT_ENTRY(ACTION_NEXT)),
 		.call = parse_vc,
 	},
 	[ACTION_VF] = {
 		.name = "vf",
-		.help = "redirect packets to virtual device function",
+		.help = "direct traffic to a virtual function ID",
 		.priv = PRIV_ACTION(VF, sizeof(struct rte_flow_action_vf)),
 		.next = NEXT(action_vf),
 		.call = parse_vc,
@@ -1708,7 +1708,7 @@ static const struct token token_list[] = {
 	},
 	[ACTION_VF_ID] = {
 		.name = "id",
-		.help = "VF ID to redirect packets to",
+		.help = "VF ID",
 		.next = NEXT(action_vf, NEXT_ENTRY(UNSIGNED)),
 		.args = ARGS(ARGS_ENTRY(struct rte_flow_action_vf, id)),
 		.call = parse_vc_conf,
diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
index 735ce6323..beedc713b 100644
--- a/doc/guides/prog_guide/rte_flow.rst
+++ b/doc/guides/prog_guide/rte_flow.rst
@@ -518,15 +518,12 @@ Usage example, matching non-TCPv4 packets only:
 Item: ``PF``
 ^^^^^^^^^^^^
 
-Matches packets addressed to the physical function of the device.
+Matches traffic originating from (ingress) or going to (egress) the physical
+function of the current device.
 
-If the underlying device function differs from the one that would normally
-receive the matched traffic, specifying this item prevents it from reaching
-that device unless the flow rule contains a `Action: PF`_. Packets are not
-duplicated between device instances by default.
+If supported, should work even if the physical function is not managed by
+the application and thus not associated with a DPDK port ID.
 
-- Likely to return an error or never match any traffic if applied to a VF
-  device.
 - Can be combined with any number of `Item: VF`_ to match both PF and VF
   traffic.
 - ``spec``, ``last`` and ``mask`` must not be set.
@@ -548,15 +545,15 @@ duplicated between device instances by default.
 Item: ``VF``
 ^^^^^^^^^^^^
 
-Matches packets addressed to a virtual function ID of the device.
+Matches traffic originating from (ingress) or going to (egress) a given
+virtual function of the current device.
 
-If the underlying device function differs from the one that would normally
-receive the matched traffic, specifying this item prevents it from reaching
-that device unless the flow rule contains a `Action: VF`_. Packets are not
-duplicated between device instances by default.
+If supported, should work even if the virtual function is not managed by the
+application and thus not associated with a DPDK port ID.
+
+Note this pattern item does not match VF representors traffic which, as
+separate entities, should be addressed through their own DPDK port IDs.
 
-- Likely to return an error or never match any traffic if this causes a VF
-  device to match traffic addressed to a different VF.
 - Can be specified multiple times to match traffic addressed to several VF
   IDs.
 - Can be combined with a PF item to match both PF and VF traffic.
@@ -1379,7 +1376,10 @@ only matching traffic goes through.
 Action: ``PF``
 ^^^^^^^^^^^^^^
 
-Redirects packets to the physical function (PF) of the current device.
+Directs matching traffic to the physical function (PF) of the current
+device.
+
+See `Item: PF`_.
 
 - No configurable properties.
 
@@ -1396,13 +1396,15 @@ Redirects packets to the physical function (PF) of the current device.
 Action: ``VF``
 ^^^^^^^^^^^^^^
 
-Redirects packets to a virtual function (VF) of the current device.
+Directs matching traffic to a given virtual function of the current device.
 
 Packets matched by a VF pattern item can be redirected to their original VF
 ID instead of the specified one. This parameter may not be available and is
 not guaranteed to work properly if the VF part is matched by a prior flow
 rule or if packets are not addressed to a VF in the first place.
 
+See `Item: VF`_.
+
 .. _table_rte_flow_action_vf:
 
 .. table:: VF
@@ -1412,7 +1414,7 @@ rule or if packets are not addressed to a VF in the first place.
    +==============+================================+
    | ``original`` | use original VF ID if possible |
    +--------------+--------------------------------+
-   | ``vf``       | VF ID to redirect packets to   |
+   | ``id``       | VF ID                          |
    +--------------+--------------------------------+
 
 Action: ``METER``
diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
index a87cd1542..2f1db9a29 100644
--- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
+++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
@@ -3202,11 +3202,11 @@ This section lists supported pattern items and their attributes, if any.
 
   - ``num {unsigned}``: number of layers covered.
 
-- ``pf``: match packets addressed to the physical function.
+- ``pf``: match traffic from/to the physical function.
 
-- ``vf``: match packets addressed to a virtual function ID.
+- ``vf``: match traffic from/to a virtual function ID.
 
-  - ``id {unsigned}``: destination VF ID.
+  - ``id {unsigned}``: VF ID.
 
 - ``port``: device-specific physical port index to use.
 
@@ -3414,12 +3414,12 @@ This section lists supported actions and their attributes, if any.
 
   - ``queues [{unsigned} [...]] end``: queue indices to use.
 
-- ``pf``: redirect packets to physical device function.
+- ``pf``: direct traffic to physical function.
 
-- ``vf``: redirect packets to virtual device function.
+- ``vf``: direct traffic to a virtual function ID.
 
   - ``original {boolean}``: use original VF ID if possible.
-  - ``id {unsigned}``: VF ID to redirect packets to.
+  - ``id {unsigned}``: VF ID.
 
 Destroying flow rules
 ~~~~~~~~~~~~~~~~~~~~~
diff --git a/drivers/net/bnxt/bnxt_filter.c b/drivers/net/bnxt/bnxt_filter.c
index 862e03188..f2ee250e8 100644
--- a/drivers/net/bnxt/bnxt_filter.c
+++ b/drivers/net/bnxt/bnxt_filter.c
@@ -276,6 +276,7 @@ bnxt_filter_type_check(const struct rte_flow_item pattern[],
 
 static int
 bnxt_validate_and_parse_flow_type(struct bnxt *bp,
+				  const struct rte_flow_attr *attr,
 				  const struct rte_flow_item pattern[],
 				  struct rte_flow_error *error,
 				  struct bnxt_filter_info *filter)
@@ -703,6 +704,16 @@ bnxt_validate_and_parse_flow_type(struct bnxt *bp,
 				return -rte_errno;
 			}
 
+			if (!attr->transfer) {
+				rte_flow_error_set(error, ENOTSUP,
+					   RTE_FLOW_ERROR_TYPE_ITEM,
+					   item,
+					   "Matching VF traffic without"
+					   " affecting it (transfer attribute)"
+					   " is unsupported");
+				return -rte_errno;
+			}
+
 			filter->mirror_vnic_id =
 			dflt_vnic = bnxt_hwrm_func_qcfg_vf_dflt_vnic_id(bp, vf);
 			if (dflt_vnic < 0) {
@@ -750,14 +761,6 @@ bnxt_flow_parse_attr(const struct rte_flow_attr *attr,
 	}
 
 	/* Not supported */
-	if (attr->transfer) {
-		rte_flow_error_set(error, EINVAL,
-				   RTE_FLOW_ERROR_TYPE_ATTR_TRANSFER,
-				   attr, "No support for transfer.");
-		return -rte_errno;
-	}
-
-	/* Not supported */
 	if (attr->priority) {
 		rte_flow_error_set(error, EINVAL,
 				   RTE_FLOW_ERROR_TYPE_ATTR_PRIORITY,
@@ -837,7 +840,8 @@ bnxt_validate_and_parse_flow(struct rte_eth_dev *dev,
 		goto ret;
 	}
 
-	rc = bnxt_validate_and_parse_flow_type(bp, pattern, error, filter);
+	rc = bnxt_validate_and_parse_flow_type(bp, attr, pattern, error,
+					       filter);
 	if (rc != 0)
 		goto ret;
 
diff --git a/drivers/net/i40e/i40e_flow.c b/drivers/net/i40e/i40e_flow.c
index 0a3f93fad..96a698a2c 100644
--- a/drivers/net/i40e/i40e_flow.c
+++ b/drivers/net/i40e/i40e_flow.c
@@ -54,6 +54,7 @@ static int i40e_flow_parse_ethertype_action(struct rte_eth_dev *dev,
 				    struct rte_flow_error *error,
 				    struct rte_eth_ethertype_filter *filter);
 static int i40e_flow_parse_fdir_pattern(struct rte_eth_dev *dev,
+					const struct rte_flow_attr *attr,
 					const struct rte_flow_item *pattern,
 					struct rte_flow_error *error,
 					struct i40e_fdir_filter_conf *filter);
@@ -1918,14 +1919,6 @@ i40e_flow_parse_attr(const struct rte_flow_attr *attr,
 	}
 
 	/* Not supported */
-	if (attr->transfer) {
-		rte_flow_error_set(error, EINVAL,
-				   RTE_FLOW_ERROR_TYPE_ATTR_TRANSFER,
-				   attr, "No support for transfer.");
-		return -rte_errno;
-	}
-
-	/* Not supported */
 	if (attr->priority) {
 		rte_flow_error_set(error, EINVAL,
 				   RTE_FLOW_ERROR_TYPE_ATTR_PRIORITY,
@@ -2429,6 +2422,7 @@ i40e_flow_fdir_get_pctype_value(struct i40e_pf *pf,
  */
 static int
 i40e_flow_parse_fdir_pattern(struct rte_eth_dev *dev,
+			     const struct rte_flow_attr *attr,
 			     const struct rte_flow_item *pattern,
 			     struct rte_flow_error *error,
 			     struct i40e_fdir_filter_conf *filter)
@@ -2969,6 +2963,16 @@ i40e_flow_parse_fdir_pattern(struct rte_eth_dev *dev,
 			break;
 		case RTE_FLOW_ITEM_TYPE_VF:
 			vf_spec = item->spec;
+			if (!attr->transfer) {
+				rte_flow_error_set(error, ENOTSUP,
+						   RTE_FLOW_ERROR_TYPE_ITEM,
+						   item,
+						   "Matching VF traffic"
+						   " without affecting it"
+						   " (transfer attribute)"
+						   " is unsupported");
+				return -rte_errno;
+			}
 			filter->input.flow_ext.is_vf = 1;
 			filter->input.flow_ext.dst_id = vf_spec->id;
 			if (filter->input.flow_ext.is_vf &&
@@ -3131,7 +3135,8 @@ i40e_flow_parse_fdir_filter(struct rte_eth_dev *dev,
 		&filter->fdir_filter;
 	int ret;
 
-	ret = i40e_flow_parse_fdir_pattern(dev, pattern, error, fdir_filter);
+	ret = i40e_flow_parse_fdir_pattern(dev, attr, pattern, error,
+					   fdir_filter);
 	if (ret)
 		return ret;
 
diff --git a/lib/librte_ether/rte_flow.h b/lib/librte_ether/rte_flow.h
index b7bdc0469..bb9d59833 100644
--- a/lib/librte_ether/rte_flow.h
+++ b/lib/librte_ether/rte_flow.h
@@ -148,13 +148,8 @@ enum rte_flow_item_type {
 	/**
 	 * [META]
 	 *
-	 * Matches packets addressed to the physical function of the device.
-	 *
-	 * If the underlying device function differs from the one that would
-	 * normally receive the matched traffic, specifying this item
-	 * prevents it from reaching that device unless the flow rule
-	 * contains a PF action. Packets are not duplicated between device
-	 * instances by default.
+	 * Matches traffic originating from (ingress) or going to (egress)
+	 * the physical function of the current device.
 	 *
 	 * No associated specification structure.
 	 */
@@ -163,13 +158,8 @@ enum rte_flow_item_type {
 	/**
 	 * [META]
 	 *
-	 * Matches packets addressed to a virtual function ID of the device.
-	 *
-	 * If the underlying device function differs from the one that would
-	 * normally receive the matched traffic, specifying this item
-	 * prevents it from reaching that device unless the flow rule
-	 * contains a VF action. Packets are not duplicated between device
-	 * instances by default.
+	 * Matches traffic originating from (ingress) or going to (egress) a
+	 * given virtual function of the current device.
 	 *
 	 * See struct rte_flow_item_vf.
 	 */
@@ -367,15 +357,15 @@ static const struct rte_flow_item_any rte_flow_item_any_mask = {
 /**
  * RTE_FLOW_ITEM_TYPE_VF
  *
- * Matches packets addressed to a virtual function ID of the device.
+ * Matches traffic originating from (ingress) or going to (egress) a given
+ * virtual function of the current device.
  *
- * If the underlying device function differs from the one that would
- * normally receive the matched traffic, specifying this item prevents it
- * from reaching that device unless the flow rule contains a VF
- * action. Packets are not duplicated between device instances by default.
+ * If supported, should work even if the virtual function is not managed by
+ * the application and thus not associated with a DPDK port ID.
+ *
+ * Note this pattern item does not match VF representors traffic which, as
+ * separate entities, should be addressed through their own DPDK port IDs.
  *
- * - Likely to return an error or never match any traffic if this causes a
- *   VF device to match traffic addressed to a different VF.
  * - Can be specified multiple times to match traffic addressed to several
  *   VF IDs.
  * - Can be combined with a PF item to match both PF and VF traffic.
@@ -383,7 +373,7 @@ static const struct rte_flow_item_any rte_flow_item_any_mask = {
  * A zeroed mask can be used to match any VF ID.
  */
 struct rte_flow_item_vf {
-	uint32_t id; /**< Destination VF ID. */
+	uint32_t id; /**< VF ID. */
 };
 
 /** Default mask for RTE_FLOW_ITEM_TYPE_VF. */
@@ -984,16 +974,16 @@ enum rte_flow_action_type {
 	RTE_FLOW_ACTION_TYPE_RSS,
 
 	/**
-	 * Redirects packets to the physical function (PF) of the current
-	 * device.
+	 * Directs matching traffic to the physical function (PF) of the
+	 * current device.
 	 *
 	 * No associated configuration structure.
 	 */
 	RTE_FLOW_ACTION_TYPE_PF,
 
 	/**
-	 * Redirects packets to the virtual function (VF) of the current
-	 * device with the specified ID.
+	 * Directs matching traffic to a given virtual function of the
+	 * current device.
 	 *
 	 * See struct rte_flow_action_vf.
 	 */
@@ -1101,7 +1091,8 @@ struct rte_flow_action_rss {
 /**
  * RTE_FLOW_ACTION_TYPE_VF
  *
- * Redirects packets to a virtual function (VF) of the current device.
+ * Directs matching traffic to a given virtual function of the current
+ * device.
  *
  * Packets matched by a VF pattern item can be redirected to their original
  * VF ID instead of the specified one. This parameter may not be available
@@ -1112,7 +1103,7 @@ struct rte_flow_action_rss {
 struct rte_flow_action_vf {
 	uint32_t original:1; /**< Use original VF ID if possible. */
 	uint32_t reserved:31; /**< Reserved, must be zero. */
-	uint32_t id; /**< VF ID to redirect packets to. */
+	uint32_t id; /**< VF ID. */
 };
 
 /**
-- 
2.11.0