1 /*
2  * Copyright (c) 2016-2017 VMware, Inc.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of EITHER the GNU General Public License
6  * version 2 as published by the Free Software Foundation or the BSD
7  * 2-Clause License. This program is distributed in the hope that it
8  * will be useful, but WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED
9  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
10  * See the GNU General Public License version 2 for more details at
11  * http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program available in the file COPYING in the main
15  * directory of this source tree.
16  *
17  * The BSD 2-Clause License
18  *
19  *     Redistribution and use in source and binary forms, with or
20  *     without modification, are permitted provided that the following
21  *     conditions are met:
22  *
23  *      - Redistributions of source code must retain the above
24  *        copyright notice, this list of conditions and the following
25  *        disclaimer.
26  *
27  *      - Redistributions in binary form must reproduce the above
28  *        copyright notice, this list of conditions and the following
29  *        disclaimer in the documentation and/or other materials
30  *        provided with the distribution.
31  *
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
35  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
36  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
37  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
38  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
39  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
42  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
43  * OF THE POSSIBILITY OF SUCH DAMAGE.
44  */
45 
46 #include <asm/page.h>
47 #include <linux/io.h>
48 #include <linux/wait.h>
49 #include <rdma/ib_addr.h>
50 #include <rdma/ib_smi.h>
51 #include <rdma/ib_user_verbs.h>
52 
53 #include "pvrdma.h"
54 
55 /**
56  * pvrdma_query_srq - query shared receive queue
57  * @ibsrq: the shared receive queue to query
58  * @srq_attr: attributes to query and return to client
59  *
60  * @return: 0 for success, otherwise returns an errno.
61  */
62 int pvrdma_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *srq_attr)
63 {
64 	struct pvrdma_dev *dev = to_vdev(ibsrq->device);
65 	struct pvrdma_srq *srq = to_vsrq(ibsrq);
66 	union pvrdma_cmd_req req;
67 	union pvrdma_cmd_resp rsp;
68 	struct pvrdma_cmd_query_srq *cmd = &req.query_srq;
69 	struct pvrdma_cmd_query_srq_resp *resp = &rsp.query_srq_resp;
70 	int ret;
71 
72 	memset(cmd, 0, sizeof(*cmd));
73 	cmd->hdr.cmd = PVRDMA_CMD_QUERY_SRQ;
74 	cmd->srq_handle = srq->srq_handle;
75 
76 	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_QUERY_SRQ_RESP);
77 	if (ret < 0) {
78 		dev_warn(&dev->pdev->dev,
79 			 "could not query shared receive queue, error: %d\n",
80 			 ret);
81 		return -EINVAL;
82 	}
83 
84 	srq_attr->srq_limit = resp->attrs.srq_limit;
85 	srq_attr->max_wr = resp->attrs.max_wr;
86 	srq_attr->max_sge = resp->attrs.max_sge;
87 
88 	return 0;
89 }
90 
91 /**
92  * pvrdma_create_srq - create shared receive queue
93  * @pd: protection domain
94  * @init_attr: shared receive queue attributes
95  * @udata: user data
96  *
97  * @return: 0 on success, otherwise returns an errno.
98  */
99 int pvrdma_create_srq(struct ib_srq *ibsrq, struct ib_srq_init_attr *init_attr,
100 		      struct ib_udata *udata)
101 {
102 	struct pvrdma_srq *srq = to_vsrq(ibsrq);
103 	struct pvrdma_dev *dev = to_vdev(ibsrq->device);
104 	union pvrdma_cmd_req req;
105 	union pvrdma_cmd_resp rsp;
106 	struct pvrdma_cmd_create_srq *cmd = &req.create_srq;
107 	struct pvrdma_cmd_create_srq_resp *resp = &rsp.create_srq_resp;
108 	struct pvrdma_create_srq_resp srq_resp = {};
109 	struct pvrdma_create_srq ucmd;
110 	unsigned long flags;
111 	int ret;
112 
113 	if (!udata) {
114 		/* No support for kernel clients. */
115 		dev_warn(&dev->pdev->dev,
116 			 "no shared receive queue support for kernel client\n");
117 		return -EOPNOTSUPP;
118 	}
119 
120 	if (init_attr->srq_type != IB_SRQT_BASIC) {
121 		dev_warn(&dev->pdev->dev,
122 			 "shared receive queue type %d not supported\n",
123 			 init_attr->srq_type);
124 		return -EINVAL;
125 	}
126 
127 	if (init_attr->attr.max_wr  > dev->dsr->caps.max_srq_wr ||
128 	    init_attr->attr.max_sge > dev->dsr->caps.max_srq_sge) {
129 		dev_warn(&dev->pdev->dev,
130 			 "shared receive queue size invalid\n");
131 		return -EINVAL;
132 	}
133 
134 	if (!atomic_add_unless(&dev->num_srqs, 1, dev->dsr->caps.max_srq))
135 		return -ENOMEM;
136 
137 	spin_lock_init(&srq->lock);
138 	refcount_set(&srq->refcnt, 1);
139 	init_completion(&srq->free);
140 
141 	dev_dbg(&dev->pdev->dev,
142 		"create shared receive queue from user space\n");
143 
144 	if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd))) {
145 		ret = -EFAULT;
146 		goto err_srq;
147 	}
148 
149 	srq->umem = ib_umem_get(ibsrq->device, ucmd.buf_addr, ucmd.buf_size, 0);
150 	if (IS_ERR(srq->umem)) {
151 		ret = PTR_ERR(srq->umem);
152 		goto err_srq;
153 	}
154 
155 	srq->npages = ib_umem_page_count(srq->umem);
156 
157 	if (srq->npages < 0 || srq->npages > PVRDMA_PAGE_DIR_MAX_PAGES) {
158 		dev_warn(&dev->pdev->dev,
159 			 "overflow pages in shared receive queue\n");
160 		ret = -EINVAL;
161 		goto err_umem;
162 	}
163 
164 	ret = pvrdma_page_dir_init(dev, &srq->pdir, srq->npages, false);
165 	if (ret) {
166 		dev_warn(&dev->pdev->dev,
167 			 "could not allocate page directory\n");
168 		goto err_umem;
169 	}
170 
171 	pvrdma_page_dir_insert_umem(&srq->pdir, srq->umem, 0);
172 
173 	memset(cmd, 0, sizeof(*cmd));
174 	cmd->hdr.cmd = PVRDMA_CMD_CREATE_SRQ;
175 	cmd->srq_type = init_attr->srq_type;
176 	cmd->nchunks = srq->npages;
177 	cmd->pd_handle = to_vpd(ibsrq->pd)->pd_handle;
178 	cmd->attrs.max_wr = init_attr->attr.max_wr;
179 	cmd->attrs.max_sge = init_attr->attr.max_sge;
180 	cmd->attrs.srq_limit = init_attr->attr.srq_limit;
181 	cmd->pdir_dma = srq->pdir.dir_dma;
182 
183 	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_SRQ_RESP);
184 	if (ret < 0) {
185 		dev_warn(&dev->pdev->dev,
186 			 "could not create shared receive queue, error: %d\n",
187 			 ret);
188 		goto err_page_dir;
189 	}
190 
191 	srq->srq_handle = resp->srqn;
192 	srq_resp.srqn = resp->srqn;
193 	spin_lock_irqsave(&dev->srq_tbl_lock, flags);
194 	dev->srq_tbl[srq->srq_handle % dev->dsr->caps.max_srq] = srq;
195 	spin_unlock_irqrestore(&dev->srq_tbl_lock, flags);
196 
197 	/* Copy udata back. */
198 	if (ib_copy_to_udata(udata, &srq_resp, sizeof(srq_resp))) {
199 		dev_warn(&dev->pdev->dev, "failed to copy back udata\n");
200 		pvrdma_destroy_srq(&srq->ibsrq, udata);
201 		return -EINVAL;
202 	}
203 
204 	return 0;
205 
206 err_page_dir:
207 	pvrdma_page_dir_cleanup(dev, &srq->pdir);
208 err_umem:
209 	ib_umem_release(srq->umem);
210 err_srq:
211 	atomic_dec(&dev->num_srqs);
212 
213 	return ret;
214 }
215 
216 static void pvrdma_free_srq(struct pvrdma_dev *dev, struct pvrdma_srq *srq)
217 {
218 	unsigned long flags;
219 
220 	spin_lock_irqsave(&dev->srq_tbl_lock, flags);
221 	dev->srq_tbl[srq->srq_handle] = NULL;
222 	spin_unlock_irqrestore(&dev->srq_tbl_lock, flags);
223 
224 	if (refcount_dec_and_test(&srq->refcnt))
225 		complete(&srq->free);
226 	wait_for_completion(&srq->free);
227 
228 	/* There is no support for kernel clients, so this is safe. */
229 	ib_umem_release(srq->umem);
230 
231 	pvrdma_page_dir_cleanup(dev, &srq->pdir);
232 
233 	atomic_dec(&dev->num_srqs);
234 }
235 
236 /**
237  * pvrdma_destroy_srq - destroy shared receive queue
238  * @srq: the shared receive queue to destroy
239  * @udata: user data or null for kernel object
240  *
241  * @return: 0 for success.
242  */
243 void pvrdma_destroy_srq(struct ib_srq *srq, struct ib_udata *udata)
244 {
245 	struct pvrdma_srq *vsrq = to_vsrq(srq);
246 	union pvrdma_cmd_req req;
247 	struct pvrdma_cmd_destroy_srq *cmd = &req.destroy_srq;
248 	struct pvrdma_dev *dev = to_vdev(srq->device);
249 	int ret;
250 
251 	memset(cmd, 0, sizeof(*cmd));
252 	cmd->hdr.cmd = PVRDMA_CMD_DESTROY_SRQ;
253 	cmd->srq_handle = vsrq->srq_handle;
254 
255 	ret = pvrdma_cmd_post(dev, &req, NULL, 0);
256 	if (ret < 0)
257 		dev_warn(&dev->pdev->dev,
258 			 "destroy shared receive queue failed, error: %d\n",
259 			 ret);
260 
261 	pvrdma_free_srq(dev, vsrq);
262 }
263 
264 /**
265  * pvrdma_modify_srq - modify shared receive queue attributes
266  * @ibsrq: the shared receive queue to modify
267  * @attr: the shared receive queue's new attributes
268  * @attr_mask: attributes mask
269  * @udata: user data
270  *
271  * @returns 0 on success, otherwise returns an errno.
272  */
273 int pvrdma_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
274 		      enum ib_srq_attr_mask attr_mask, struct ib_udata *udata)
275 {
276 	struct pvrdma_srq *vsrq = to_vsrq(ibsrq);
277 	union pvrdma_cmd_req req;
278 	struct pvrdma_cmd_modify_srq *cmd = &req.modify_srq;
279 	struct pvrdma_dev *dev = to_vdev(ibsrq->device);
280 	int ret;
281 
282 	/* Only support SRQ limit. */
283 	if (!(attr_mask & IB_SRQ_LIMIT))
284 		return -EINVAL;
285 
286 	memset(cmd, 0, sizeof(*cmd));
287 	cmd->hdr.cmd = PVRDMA_CMD_MODIFY_SRQ;
288 	cmd->srq_handle = vsrq->srq_handle;
289 	cmd->attrs.srq_limit = attr->srq_limit;
290 	cmd->attr_mask = attr_mask;
291 
292 	ret = pvrdma_cmd_post(dev, &req, NULL, 0);
293 	if (ret < 0) {
294 		dev_warn(&dev->pdev->dev,
295 			 "could not modify shared receive queue, error: %d\n",
296 			 ret);
297 
298 		return -EINVAL;
299 	}
300 
301 	return ret;
302 }
303