1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2 // Copyright (c) 2019 Mellanox Technologies.
3 
4 #include <linux/mlx5/fs.h>
5 #include "eswitch.h"
6 
7 struct mlx5_termtbl_handle {
8 	struct hlist_node termtbl_hlist;
9 
10 	struct mlx5_flow_table *termtbl;
11 	struct mlx5_flow_act flow_act;
12 	struct mlx5_flow_destination dest;
13 
14 	struct mlx5_flow_handle *rule;
15 	int ref_count;
16 };
17 
18 static u32
19 mlx5_eswitch_termtbl_hash(struct mlx5_flow_act *flow_act,
20 			  struct mlx5_flow_destination *dest)
21 {
22 	u32 hash;
23 
24 	hash = jhash_1word(flow_act->action, 0);
25 	hash = jhash((const void *)&flow_act->vlan,
26 		     sizeof(flow_act->vlan), hash);
27 	hash = jhash((const void *)&dest->vport.num,
28 		     sizeof(dest->vport.num), hash);
29 	hash = jhash((const void *)&dest->vport.vhca_id,
30 		     sizeof(dest->vport.num), hash);
31 	return hash;
32 }
33 
34 static int
35 mlx5_eswitch_termtbl_cmp(struct mlx5_flow_act *flow_act1,
36 			 struct mlx5_flow_destination *dest1,
37 			 struct mlx5_flow_act *flow_act2,
38 			 struct mlx5_flow_destination *dest2)
39 {
40 	return flow_act1->action != flow_act2->action ||
41 	       dest1->vport.num != dest2->vport.num ||
42 	       dest1->vport.vhca_id != dest2->vport.vhca_id ||
43 	       memcmp(&flow_act1->vlan, &flow_act2->vlan,
44 		      sizeof(flow_act1->vlan));
45 }
46 
47 static int
48 mlx5_eswitch_termtbl_create(struct mlx5_core_dev *dev,
49 			    struct mlx5_termtbl_handle *tt,
50 			    struct mlx5_flow_act *flow_act)
51 {
52 	static const struct mlx5_flow_spec spec = {};
53 	struct mlx5_flow_namespace *root_ns;
54 	int prio, flags;
55 	int err;
56 
57 	root_ns = mlx5_get_flow_namespace(dev, MLX5_FLOW_NAMESPACE_FDB);
58 	if (!root_ns) {
59 		esw_warn(dev, "Failed to get FDB flow namespace\n");
60 		return -EOPNOTSUPP;
61 	}
62 
63 	/* As this is the terminating action then the termination table is the
64 	 * same prio as the slow path
65 	 */
66 	prio = FDB_SLOW_PATH;
67 	flags = MLX5_FLOW_TABLE_TERMINATION;
68 	tt->termtbl = mlx5_create_auto_grouped_flow_table(root_ns, prio, 1, 1,
69 							  0, flags);
70 	if (IS_ERR(tt->termtbl)) {
71 		esw_warn(dev, "Failed to create termination table\n");
72 		return -EOPNOTSUPP;
73 	}
74 
75 	tt->rule = mlx5_add_flow_rules(tt->termtbl, &spec, flow_act,
76 				       &tt->dest, 1);
77 
78 	if (IS_ERR(tt->rule)) {
79 		esw_warn(dev, "Failed to create termination table rule\n");
80 		goto add_flow_err;
81 	}
82 	return 0;
83 
84 add_flow_err:
85 	err = mlx5_destroy_flow_table(tt->termtbl);
86 	if (err)
87 		esw_warn(dev, "Failed to destroy termination table\n");
88 
89 	return -EOPNOTSUPP;
90 }
91 
92 static struct mlx5_termtbl_handle *
93 mlx5_eswitch_termtbl_get_create(struct mlx5_eswitch *esw,
94 				struct mlx5_flow_act *flow_act,
95 				struct mlx5_flow_destination *dest)
96 {
97 	struct mlx5_termtbl_handle *tt;
98 	bool found = false;
99 	u32 hash_key;
100 	int err;
101 
102 	mutex_lock(&esw->offloads.termtbl_mutex);
103 
104 	hash_key = mlx5_eswitch_termtbl_hash(flow_act, dest);
105 	hash_for_each_possible(esw->offloads.termtbl_tbl, tt,
106 			       termtbl_hlist, hash_key) {
107 		if (!mlx5_eswitch_termtbl_cmp(&tt->flow_act, &tt->dest,
108 					      flow_act, dest)) {
109 			found = true;
110 			break;
111 		}
112 	}
113 	if (found)
114 		goto tt_add_ref;
115 
116 	tt = kzalloc(sizeof(*tt), GFP_KERNEL);
117 	if (!tt) {
118 		err = -ENOMEM;
119 		goto tt_create_err;
120 	}
121 
122 	tt->dest.type = MLX5_FLOW_DESTINATION_TYPE_VPORT;
123 	tt->dest.vport.num = dest->vport.num;
124 	tt->dest.vport.vhca_id = dest->vport.vhca_id;
125 	memcpy(&tt->flow_act, flow_act, sizeof(*flow_act));
126 
127 	err = mlx5_eswitch_termtbl_create(esw->dev, tt, flow_act);
128 	if (err) {
129 		esw_warn(esw->dev, "Failed to create termination table\n");
130 		goto tt_create_err;
131 	}
132 	hash_add(esw->offloads.termtbl_tbl, &tt->termtbl_hlist, hash_key);
133 tt_add_ref:
134 	tt->ref_count++;
135 	mutex_unlock(&esw->offloads.termtbl_mutex);
136 	return tt;
137 tt_create_err:
138 	kfree(tt);
139 	mutex_unlock(&esw->offloads.termtbl_mutex);
140 	return ERR_PTR(err);
141 }
142 
143 void
144 mlx5_eswitch_termtbl_put(struct mlx5_eswitch *esw,
145 			 struct mlx5_termtbl_handle *tt)
146 {
147 	mutex_lock(&esw->offloads.termtbl_mutex);
148 	if (--tt->ref_count == 0)
149 		hash_del(&tt->termtbl_hlist);
150 	mutex_unlock(&esw->offloads.termtbl_mutex);
151 
152 	if (!tt->ref_count) {
153 		mlx5_del_flow_rules(tt->rule);
154 		mlx5_destroy_flow_table(tt->termtbl);
155 		kfree(tt);
156 	}
157 }
158 
159 static void
160 mlx5_eswitch_termtbl_actions_move(struct mlx5_flow_act *src,
161 				  struct mlx5_flow_act *dst)
162 {
163 	if (!(src->action & MLX5_FLOW_CONTEXT_ACTION_VLAN_PUSH))
164 		return;
165 
166 	src->action &= ~MLX5_FLOW_CONTEXT_ACTION_VLAN_PUSH;
167 	dst->action |= MLX5_FLOW_CONTEXT_ACTION_VLAN_PUSH;
168 	memcpy(&dst->vlan[0], &src->vlan[0], sizeof(src->vlan[0]));
169 	memset(&src->vlan[0], 0, sizeof(src->vlan[0]));
170 
171 	if (!(src->action & MLX5_FLOW_CONTEXT_ACTION_VLAN_PUSH_2))
172 		return;
173 
174 	src->action &= ~MLX5_FLOW_CONTEXT_ACTION_VLAN_PUSH_2;
175 	dst->action |= MLX5_FLOW_CONTEXT_ACTION_VLAN_PUSH_2;
176 	memcpy(&dst->vlan[1], &src->vlan[1], sizeof(src->vlan[1]));
177 	memset(&src->vlan[1], 0, sizeof(src->vlan[1]));
178 }
179 
180 static bool mlx5_eswitch_offload_is_uplink_port(const struct mlx5_eswitch *esw,
181 						const struct mlx5_flow_spec *spec)
182 {
183 	u32 port_mask, port_value;
184 
185 	if (MLX5_CAP_ESW_FLOWTABLE(esw->dev, flow_source))
186 		return spec->flow_context.flow_source ==
187 					MLX5_FLOW_CONTEXT_FLOW_SOURCE_UPLINK;
188 
189 	port_mask = MLX5_GET(fte_match_param, spec->match_criteria,
190 			     misc_parameters.source_port);
191 	port_value = MLX5_GET(fte_match_param, spec->match_value,
192 			      misc_parameters.source_port);
193 	return (port_mask & port_value & 0xffff) == MLX5_VPORT_UPLINK;
194 }
195 
196 bool
197 mlx5_eswitch_termtbl_required(struct mlx5_eswitch *esw,
198 			      struct mlx5_flow_act *flow_act,
199 			      struct mlx5_flow_spec *spec)
200 {
201 	if (!MLX5_CAP_ESW_FLOWTABLE_FDB(esw->dev, termination_table))
202 		return false;
203 
204 	/* push vlan on RX */
205 	return (flow_act->action & MLX5_FLOW_CONTEXT_ACTION_VLAN_PUSH) &&
206 		mlx5_eswitch_offload_is_uplink_port(esw, spec);
207 }
208 
209 struct mlx5_flow_handle *
210 mlx5_eswitch_add_termtbl_rule(struct mlx5_eswitch *esw,
211 			      struct mlx5_flow_table *fdb,
212 			      struct mlx5_flow_spec *spec,
213 			      struct mlx5_esw_flow_attr *attr,
214 			      struct mlx5_flow_act *flow_act,
215 			      struct mlx5_flow_destination *dest,
216 			      int num_dest)
217 {
218 	struct mlx5_flow_act term_tbl_act = {};
219 	struct mlx5_flow_handle *rule = NULL;
220 	bool term_table_created = false;
221 	int num_vport_dests = 0;
222 	int i, curr_dest;
223 
224 	mlx5_eswitch_termtbl_actions_move(flow_act, &term_tbl_act);
225 	term_tbl_act.action |= MLX5_FLOW_CONTEXT_ACTION_FWD_DEST;
226 
227 	for (i = 0; i < num_dest; i++) {
228 		struct mlx5_termtbl_handle *tt;
229 
230 		/* only vport destinations can be terminated */
231 		if (dest[i].type != MLX5_FLOW_DESTINATION_TYPE_VPORT)
232 			continue;
233 
234 		/* get the terminating table for the action list */
235 		tt = mlx5_eswitch_termtbl_get_create(esw, &term_tbl_act,
236 						     &dest[i]);
237 		if (IS_ERR(tt)) {
238 			esw_warn(esw->dev, "Failed to create termination table\n");
239 			goto revert_changes;
240 		}
241 		attr->dests[num_vport_dests].termtbl = tt;
242 		num_vport_dests++;
243 
244 		/* link the destination with the termination table */
245 		dest[i].type = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;
246 		dest[i].ft = tt->termtbl;
247 		term_table_created = true;
248 	}
249 
250 	/* at least one destination should reference a termination table */
251 	if (!term_table_created)
252 		goto revert_changes;
253 
254 	/* create the FTE */
255 	rule = mlx5_add_flow_rules(fdb, spec, flow_act, dest, num_dest);
256 	if (IS_ERR(rule))
257 		goto revert_changes;
258 
259 	goto out;
260 
261 revert_changes:
262 	/* revert the changes that were made to the original flow_act
263 	 * and fall-back to the original rule actions
264 	 */
265 	mlx5_eswitch_termtbl_actions_move(&term_tbl_act, flow_act);
266 
267 	for (curr_dest = 0; curr_dest < num_vport_dests; curr_dest++) {
268 		struct mlx5_termtbl_handle *tt = attr->dests[curr_dest].termtbl;
269 
270 		/* search for the destination associated with the
271 		 * current term table
272 		 */
273 		for (i = 0; i < num_dest; i++) {
274 			if (dest[i].ft != tt->termtbl)
275 				continue;
276 
277 			memset(&dest[i], 0, sizeof(dest[i]));
278 			dest[i].type = MLX5_FLOW_DESTINATION_TYPE_VPORT;
279 			dest[i].vport.num = tt->dest.vport.num;
280 			dest[i].vport.vhca_id = tt->dest.vport.vhca_id;
281 			mlx5_eswitch_termtbl_put(esw, tt);
282 			break;
283 		}
284 	}
285 	rule = mlx5_add_flow_rules(fdb, spec, flow_act, dest, num_dest);
286 out:
287 	return rule;
288 }
289