1 /*
2  * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/hardirq.h>
36 #include <linux/mlx5/driver.h>
37 #include <rdma/ib_verbs.h>
38 #include <linux/mlx5/cq.h>
39 #include "mlx5_core.h"
40 #include "lib/eq.h"
41 
42 #define TASKLET_MAX_TIME 2
43 #define TASKLET_MAX_TIME_JIFFIES msecs_to_jiffies(TASKLET_MAX_TIME)
44 
45 void mlx5_cq_tasklet_cb(struct tasklet_struct *t)
46 {
47 	unsigned long flags;
48 	unsigned long end = jiffies + TASKLET_MAX_TIME_JIFFIES;
49 	struct mlx5_eq_tasklet *ctx = from_tasklet(ctx, t, task);
50 	struct mlx5_core_cq *mcq;
51 	struct mlx5_core_cq *temp;
52 
53 	spin_lock_irqsave(&ctx->lock, flags);
54 	list_splice_tail_init(&ctx->list, &ctx->process_list);
55 	spin_unlock_irqrestore(&ctx->lock, flags);
56 
57 	list_for_each_entry_safe(mcq, temp, &ctx->process_list,
58 				 tasklet_ctx.list) {
59 		list_del_init(&mcq->tasklet_ctx.list);
60 		mcq->tasklet_ctx.comp(mcq, NULL);
61 		mlx5_cq_put(mcq);
62 		if (time_after(jiffies, end))
63 			break;
64 	}
65 
66 	if (!list_empty(&ctx->process_list))
67 		tasklet_schedule(&ctx->task);
68 }
69 
70 static void mlx5_add_cq_to_tasklet(struct mlx5_core_cq *cq,
71 				   struct mlx5_eqe *eqe)
72 {
73 	unsigned long flags;
74 	struct mlx5_eq_tasklet *tasklet_ctx = cq->tasklet_ctx.priv;
75 
76 	spin_lock_irqsave(&tasklet_ctx->lock, flags);
77 	/* When migrating CQs between EQs will be implemented, please note
78 	 * that you need to sync this point. It is possible that
79 	 * while migrating a CQ, completions on the old EQs could
80 	 * still arrive.
81 	 */
82 	if (list_empty_careful(&cq->tasklet_ctx.list)) {
83 		mlx5_cq_hold(cq);
84 		list_add_tail(&cq->tasklet_ctx.list, &tasklet_ctx->list);
85 	}
86 	spin_unlock_irqrestore(&tasklet_ctx->lock, flags);
87 }
88 
89 int mlx5_core_create_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
90 			u32 *in, int inlen, u32 *out, int outlen)
91 {
92 	int eqn = MLX5_GET(cqc, MLX5_ADDR_OF(create_cq_in, in, cq_context), c_eqn);
93 	u32 din[MLX5_ST_SZ_DW(destroy_cq_in)] = {};
94 	struct mlx5_eq_comp *eq;
95 	int err;
96 
97 	eq = mlx5_eqn2comp_eq(dev, eqn);
98 	if (IS_ERR(eq))
99 		return PTR_ERR(eq);
100 
101 	memset(out, 0, outlen);
102 	MLX5_SET(create_cq_in, in, opcode, MLX5_CMD_OP_CREATE_CQ);
103 	err = mlx5_cmd_exec(dev, in, inlen, out, outlen);
104 	if (err)
105 		return err;
106 
107 	cq->cqn = MLX5_GET(create_cq_out, out, cqn);
108 	cq->cons_index = 0;
109 	cq->arm_sn     = 0;
110 	cq->eq         = eq;
111 	cq->uid = MLX5_GET(create_cq_in, in, uid);
112 	refcount_set(&cq->refcount, 1);
113 	init_completion(&cq->free);
114 	if (!cq->comp)
115 		cq->comp = mlx5_add_cq_to_tasklet;
116 	/* assuming CQ will be deleted before the EQ */
117 	cq->tasklet_ctx.priv = &eq->tasklet_ctx;
118 	INIT_LIST_HEAD(&cq->tasklet_ctx.list);
119 
120 	/* Add to comp EQ CQ tree to recv comp events */
121 	err = mlx5_eq_add_cq(&eq->core, cq);
122 	if (err)
123 		goto err_cmd;
124 
125 	/* Add to async EQ CQ tree to recv async events */
126 	err = mlx5_eq_add_cq(mlx5_get_async_eq(dev), cq);
127 	if (err)
128 		goto err_cq_add;
129 
130 	cq->pid = current->pid;
131 	err = mlx5_debug_cq_add(dev, cq);
132 	if (err)
133 		mlx5_core_dbg(dev, "failed adding CP 0x%x to debug file system\n",
134 			      cq->cqn);
135 
136 	cq->uar = dev->priv.uar;
137 
138 	return 0;
139 
140 err_cq_add:
141 	mlx5_eq_del_cq(&eq->core, cq);
142 err_cmd:
143 	MLX5_SET(destroy_cq_in, din, opcode, MLX5_CMD_OP_DESTROY_CQ);
144 	MLX5_SET(destroy_cq_in, din, cqn, cq->cqn);
145 	MLX5_SET(destroy_cq_in, din, uid, cq->uid);
146 	mlx5_cmd_exec_in(dev, destroy_cq, din);
147 	return err;
148 }
149 EXPORT_SYMBOL(mlx5_core_create_cq);
150 
151 int mlx5_core_destroy_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq)
152 {
153 	u32 in[MLX5_ST_SZ_DW(destroy_cq_in)] = {};
154 	int err;
155 
156 	mlx5_eq_del_cq(mlx5_get_async_eq(dev), cq);
157 	mlx5_eq_del_cq(&cq->eq->core, cq);
158 
159 	MLX5_SET(destroy_cq_in, in, opcode, MLX5_CMD_OP_DESTROY_CQ);
160 	MLX5_SET(destroy_cq_in, in, cqn, cq->cqn);
161 	MLX5_SET(destroy_cq_in, in, uid, cq->uid);
162 	err = mlx5_cmd_exec_in(dev, destroy_cq, in);
163 	if (err)
164 		return err;
165 
166 	synchronize_irq(cq->irqn);
167 
168 	mlx5_debug_cq_remove(dev, cq);
169 	mlx5_cq_put(cq);
170 	wait_for_completion(&cq->free);
171 
172 	return 0;
173 }
174 EXPORT_SYMBOL(mlx5_core_destroy_cq);
175 
176 int mlx5_core_query_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
177 		       u32 *out)
178 {
179 	u32 in[MLX5_ST_SZ_DW(query_cq_in)] = {};
180 
181 	MLX5_SET(query_cq_in, in, opcode, MLX5_CMD_OP_QUERY_CQ);
182 	MLX5_SET(query_cq_in, in, cqn, cq->cqn);
183 	return mlx5_cmd_exec_inout(dev, query_cq, in, out);
184 }
185 EXPORT_SYMBOL(mlx5_core_query_cq);
186 
187 int mlx5_core_modify_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
188 			u32 *in, int inlen)
189 {
190 	u32 out[MLX5_ST_SZ_DW(modify_cq_out)] = {};
191 
192 	MLX5_SET(modify_cq_in, in, opcode, MLX5_CMD_OP_MODIFY_CQ);
193 	MLX5_SET(modify_cq_in, in, uid, cq->uid);
194 	return mlx5_cmd_exec(dev, in, inlen, out, sizeof(out));
195 }
196 EXPORT_SYMBOL(mlx5_core_modify_cq);
197 
198 int mlx5_core_modify_cq_moderation(struct mlx5_core_dev *dev,
199 				   struct mlx5_core_cq *cq,
200 				   u16 cq_period,
201 				   u16 cq_max_count)
202 {
203 	u32 in[MLX5_ST_SZ_DW(modify_cq_in)] = {};
204 	void *cqc;
205 
206 	MLX5_SET(modify_cq_in, in, cqn, cq->cqn);
207 	cqc = MLX5_ADDR_OF(modify_cq_in, in, cq_context);
208 	MLX5_SET(cqc, cqc, cq_period, cq_period);
209 	MLX5_SET(cqc, cqc, cq_max_count, cq_max_count);
210 	MLX5_SET(modify_cq_in, in,
211 		 modify_field_select_resize_field_select.modify_field_select.modify_field_select,
212 		 MLX5_CQ_MODIFY_PERIOD | MLX5_CQ_MODIFY_COUNT);
213 
214 	return mlx5_core_modify_cq(dev, cq, in, sizeof(in));
215 }
216 EXPORT_SYMBOL(mlx5_core_modify_cq_moderation);
217