[PATCH net-next V4 10/12] devlink: Add resource scope filtering to resource dump

[Tariq Toukan <tariqt@nvidia.com>]

From: Or Har-Toov <ohartoov@nvidia.com>

Allow filtering the resource dump to device-level or port-level
resources using the 'scope' option.

Example - dump only device-level resources:

  $ devlink resource show scope dev
  pci/0000:03:00.0:
    name max_local_SFs size 128 unit entry dpipe_tables none
    name max_external_SFs size 128 unit entry dpipe_tables none
  pci/0000:03:00.1:
    name max_local_SFs size 128 unit entry dpipe_tables none
    name max_external_SFs size 128 unit entry dpipe_tables none

Example - dump only port-level resources:

  $ devlink resource show scope port
  pci/0000:03:00.0/196608:
    name max_SFs size 128 unit entry dpipe_tables none
  pci/0000:03:00.0/196609:
    name max_SFs size 128 unit entry dpipe_tables none
  pci/0000:03:00.1/196708:
    name max_SFs size 128 unit entry dpipe_tables none
  pci/0000:03:00.1/196709:
    name max_SFs size 128 unit entry dpipe_tables none

Signed-off-by: Or Har-Toov <ohartoov@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
 Documentation/netlink/specs/devlink.yaml | 24 +++++++++++++++++-
 include/uapi/linux/devlink.h             | 17 +++++++++++++
 net/devlink/netlink_gen.c                |  5 ++--
 net/devlink/resource.c                   | 32 ++++++++++++++++++++++--
 4 files changed, 73 insertions(+), 5 deletions(-)

diff --git a/Documentation/netlink/specs/devlink.yaml b/Documentation/netlink/specs/devlink.yaml
index 34aa81ba689e..b7d0490fc49d 100644
--- a/Documentation/netlink/specs/devlink.yaml
+++ b/Documentation/netlink/specs/devlink.yaml
@@ -157,6 +157,14 @@ definitions:
     entries:
       -
         name: entry
+  -
+    type: enum
+    name: resource-scope
+    entries:
+      -
+        name: dev
+      -
+        name: port
   -
     type: enum
     name: reload-action
@@ -873,6 +881,16 @@ attribute-sets:
         doc: Unique devlink instance index.
         checks:
           max: u32-max
+      -
+        name: resource-scope-mask
+        type: bitfield32
+        enum: resource-scope
+        enum-as-flags: true
+        doc: |
+          Bitmask selecting which resource classes to include in a
+          resource-dump response. Bit 0 (dev) selects device-level
+          resources; bit 1 (port) selects port-level resources.
+          When absent all classes are returned.
   -
     name: dl-dev-stats
     subset-of: devlink
@@ -1775,7 +1793,11 @@ operations:
             - resource-list
       dump:
         request:
-          attributes: *dev-id-attrs
+          attributes:
+            - bus-name
+            - dev-name
+            - index
+            - resource-scope-mask
         reply: *resource-dump-reply
 
     -
diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
index 7de2d8cc862f..e0a0b523ce5c 100644
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -645,6 +645,7 @@ enum devlink_attr {
 	DEVLINK_ATTR_PARAM_RESET_DEFAULT,	/* flag */
 
 	DEVLINK_ATTR_INDEX,			/* uint */
+	DEVLINK_ATTR_RESOURCE_SCOPE_MASK,	/* bitfield32 */
 
 	/* Add new attributes above here, update the spec in
 	 * Documentation/netlink/specs/devlink.yaml and re-generate
@@ -704,6 +705,22 @@ enum devlink_resource_unit {
 	DEVLINK_RESOURCE_UNIT_ENTRY,
 };
 
+enum devlink_resource_scope {
+	DEVLINK_RESOURCE_SCOPE_DEV_BIT,
+	DEVLINK_RESOURCE_SCOPE_PORT_BIT,
+
+	__DEVLINK_RESOURCE_SCOPE_MAX_BIT,
+	DEVLINK_RESOURCE_SCOPE_MAX_BIT =
+		__DEVLINK_RESOURCE_SCOPE_MAX_BIT - 1
+};
+
+#define DEVLINK_RESOURCE_SCOPE_DEV \
+	_BITUL(DEVLINK_RESOURCE_SCOPE_DEV_BIT)
+#define DEVLINK_RESOURCE_SCOPE_PORT \
+	_BITUL(DEVLINK_RESOURCE_SCOPE_PORT_BIT)
+#define DEVLINK_RESOURCE_SCOPE_VALID_MASK \
+	(_BITUL(__DEVLINK_RESOURCE_SCOPE_MAX_BIT) - 1)
+
 enum devlink_port_fn_attr_cap {
 	DEVLINK_PORT_FN_ATTR_CAP_ROCE_BIT,
 	DEVLINK_PORT_FN_ATTR_CAP_MIGRATABLE_BIT,
diff --git a/net/devlink/netlink_gen.c b/net/devlink/netlink_gen.c
index 9cc372d9ee41..6d4abd8b828d 100644
--- a/net/devlink/netlink_gen.c
+++ b/net/devlink/netlink_gen.c
@@ -313,10 +313,11 @@ static const struct nla_policy devlink_resource_dump_do_nl_policy[DEVLINK_ATTR_I
 };
 
 /* DEVLINK_CMD_RESOURCE_DUMP - dump */
-static const struct nla_policy devlink_resource_dump_dump_nl_policy[DEVLINK_ATTR_INDEX + 1] = {
+static const struct nla_policy devlink_resource_dump_dump_nl_policy[DEVLINK_ATTR_RESOURCE_SCOPE_MASK + 1] = {
 	[DEVLINK_ATTR_BUS_NAME] = { .type = NLA_NUL_STRING, },
 	[DEVLINK_ATTR_DEV_NAME] = { .type = NLA_NUL_STRING, },
 	[DEVLINK_ATTR_INDEX] = NLA_POLICY_FULL_RANGE(NLA_UINT, &devlink_attr_index_range),
+	[DEVLINK_ATTR_RESOURCE_SCOPE_MASK] = NLA_POLICY_BITFIELD32(3),
 };
 
 /* DEVLINK_CMD_RELOAD - do */
@@ -974,7 +975,7 @@ const struct genl_split_ops devlink_nl_ops[75] = {
 		.cmd		= DEVLINK_CMD_RESOURCE_DUMP,
 		.dumpit		= devlink_nl_resource_dump_dumpit,
 		.policy		= devlink_resource_dump_dump_nl_policy,
-		.maxattr	= DEVLINK_ATTR_INDEX,
+		.maxattr	= DEVLINK_ATTR_RESOURCE_SCOPE_MASK,
 		.flags		= GENL_CMD_CAP_DUMP,
 	},
 	{
diff --git a/net/devlink/resource.c b/net/devlink/resource.c
index 0f1d90bc4b09..c22338b2571d 100644
--- a/net/devlink/resource.c
+++ b/net/devlink/resource.c
@@ -341,6 +341,22 @@ int devlink_nl_resource_dump_doit(struct sk_buff *skb, struct genl_info *info)
 	return devlink_resource_fill(info, DEVLINK_CMD_RESOURCE_DUMP, 0);
 }
 
+static u32 devlink_resource_scope_get(struct nlattr **attrs, int *flags)
+{
+	struct nla_bitfield32 scope;
+	u32 value;
+
+	if (!attrs || !attrs[DEVLINK_ATTR_RESOURCE_SCOPE_MASK])
+		return DEVLINK_RESOURCE_SCOPE_VALID_MASK;
+
+	scope = nla_get_bitfield32(attrs[DEVLINK_ATTR_RESOURCE_SCOPE_MASK]);
+	value = scope.value & scope.selector;
+	if (value != DEVLINK_RESOURCE_SCOPE_VALID_MASK)
+		*flags |= NLM_F_DUMP_FILTERED;
+
+	return value;
+}
+
 static int
 devlink_resource_dump_fill_one(struct sk_buff *skb, struct devlink *devlink,
 			       struct devlink_port *devlink_port,
@@ -400,16 +416,27 @@ devlink_nl_resource_dump_one(struct sk_buff *skb, struct devlink *devlink,
 	struct devlink_nl_dump_state *state = devlink_dump_state(cb);
 	struct devlink_port *devlink_port;
 	unsigned long port_idx;
+	u32 scope;
 	int err;
 
-	if (!state->port_number) {
+	scope = devlink_resource_scope_get(genl_info_dump(cb)->attrs, &flags);
+	if (!scope) {
+		NL_SET_ERR_MSG_ATTR(genl_info_dump(cb)->extack,
+				    genl_info_dump(cb)->attrs[DEVLINK_ATTR_RESOURCE_SCOPE_MASK],
+				    "empty resource scope selection");
+		return -EINVAL;
+	}
+	if (!state->port_number && (scope & DEVLINK_RESOURCE_SCOPE_DEV)) {
 		err = devlink_resource_dump_fill_one(skb, devlink, NULL,
-						     cb, flags, &state->idx);
+						     cb, flags,
+						     &state->idx);
 		if (err)
 			return err;
 		state->idx = 0;
 	}
 
+	if (!(scope & DEVLINK_RESOURCE_SCOPE_PORT))
+		goto out;
 	xa_for_each_start(&devlink->ports, port_idx, devlink_port,
 			  state->port_number ? state->port_number - 1 : 0) {
 		err = devlink_resource_dump_fill_one(skb, devlink, devlink_port,
@@ -420,6 +447,7 @@ devlink_nl_resource_dump_one(struct sk_buff *skb, struct devlink *devlink,
 		}
 		state->idx = 0;
 	}
+out:
 	state->port_number = 0;
 	return 0;
 }
-- 
2.44.0