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: the ib_srq pointer on success, otherwise returns an errno.
98  */
99 struct ib_srq *pvrdma_create_srq(struct ib_pd *pd,
100 				 struct ib_srq_init_attr *init_attr,
101 				 struct ib_udata *udata)
102 {
103 	struct pvrdma_srq *srq = NULL;
104 	struct pvrdma_dev *dev = to_vdev(pd->device);
105 	union pvrdma_cmd_req req;
106 	union pvrdma_cmd_resp rsp;
107 	struct pvrdma_cmd_create_srq *cmd = &req.create_srq;
108 	struct pvrdma_cmd_create_srq_resp *resp = &rsp.create_srq_resp;
109 	struct pvrdma_create_srq_resp srq_resp = {0};
110 	struct pvrdma_create_srq ucmd;
111 	unsigned long flags;
112 	int ret;
113 
114 	if (!udata) {
115 		/* No support for kernel clients. */
116 		dev_warn(&dev->pdev->dev,
117 			 "no shared receive queue support for kernel client\n");
118 		return ERR_PTR(-EOPNOTSUPP);
119 	}
120 
121 	if (init_attr->srq_type != IB_SRQT_BASIC) {
122 		dev_warn(&dev->pdev->dev,
123 			 "shared receive queue type %d not supported\n",
124 			 init_attr->srq_type);
125 		return ERR_PTR(-EINVAL);
126 	}
127 
128 	if (init_attr->attr.max_wr  > dev->dsr->caps.max_srq_wr ||
129 	    init_attr->attr.max_sge > dev->dsr->caps.max_srq_sge) {
130 		dev_warn(&dev->pdev->dev,
131 			 "shared receive queue size invalid\n");
132 		return ERR_PTR(-EINVAL);
133 	}
134 
135 	if (!atomic_add_unless(&dev->num_srqs, 1, dev->dsr->caps.max_srq))
136 		return ERR_PTR(-ENOMEM);
137 
138 	srq = kmalloc(sizeof(*srq), GFP_KERNEL);
139 	if (!srq) {
140 		ret = -ENOMEM;
141 		goto err_srq;
142 	}
143 
144 	spin_lock_init(&srq->lock);
145 	refcount_set(&srq->refcnt, 1);
146 	init_completion(&srq->free);
147 
148 	dev_dbg(&dev->pdev->dev,
149 		"create shared receive queue from user space\n");
150 
151 	if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd))) {
152 		ret = -EFAULT;
153 		goto err_srq;
154 	}
155 
156 	srq->umem = ib_umem_get(udata, ucmd.buf_addr, ucmd.buf_size, 0, 0);
157 	if (IS_ERR(srq->umem)) {
158 		ret = PTR_ERR(srq->umem);
159 		goto err_srq;
160 	}
161 
162 	srq->npages = ib_umem_page_count(srq->umem);
163 
164 	if (srq->npages < 0 || srq->npages > PVRDMA_PAGE_DIR_MAX_PAGES) {
165 		dev_warn(&dev->pdev->dev,
166 			 "overflow pages in shared receive queue\n");
167 		ret = -EINVAL;
168 		goto err_umem;
169 	}
170 
171 	ret = pvrdma_page_dir_init(dev, &srq->pdir, srq->npages, false);
172 	if (ret) {
173 		dev_warn(&dev->pdev->dev,
174 			 "could not allocate page directory\n");
175 		goto err_umem;
176 	}
177 
178 	pvrdma_page_dir_insert_umem(&srq->pdir, srq->umem, 0);
179 
180 	memset(cmd, 0, sizeof(*cmd));
181 	cmd->hdr.cmd = PVRDMA_CMD_CREATE_SRQ;
182 	cmd->srq_type = init_attr->srq_type;
183 	cmd->nchunks = srq->npages;
184 	cmd->pd_handle = to_vpd(pd)->pd_handle;
185 	cmd->attrs.max_wr = init_attr->attr.max_wr;
186 	cmd->attrs.max_sge = init_attr->attr.max_sge;
187 	cmd->attrs.srq_limit = init_attr->attr.srq_limit;
188 	cmd->pdir_dma = srq->pdir.dir_dma;
189 
190 	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_SRQ_RESP);
191 	if (ret < 0) {
192 		dev_warn(&dev->pdev->dev,
193 			 "could not create shared receive queue, error: %d\n",
194 			 ret);
195 		goto err_page_dir;
196 	}
197 
198 	srq->srq_handle = resp->srqn;
199 	srq_resp.srqn = resp->srqn;
200 	spin_lock_irqsave(&dev->srq_tbl_lock, flags);
201 	dev->srq_tbl[srq->srq_handle % dev->dsr->caps.max_srq] = srq;
202 	spin_unlock_irqrestore(&dev->srq_tbl_lock, flags);
203 
204 	/* Copy udata back. */
205 	if (ib_copy_to_udata(udata, &srq_resp, sizeof(srq_resp))) {
206 		dev_warn(&dev->pdev->dev, "failed to copy back udata\n");
207 		pvrdma_destroy_srq(&srq->ibsrq);
208 		return ERR_PTR(-EINVAL);
209 	}
210 
211 	return &srq->ibsrq;
212 
213 err_page_dir:
214 	pvrdma_page_dir_cleanup(dev, &srq->pdir);
215 err_umem:
216 	ib_umem_release(srq->umem);
217 err_srq:
218 	kfree(srq);
219 	atomic_dec(&dev->num_srqs);
220 
221 	return ERR_PTR(ret);
222 }
223 
224 static void pvrdma_free_srq(struct pvrdma_dev *dev, struct pvrdma_srq *srq)
225 {
226 	unsigned long flags;
227 
228 	spin_lock_irqsave(&dev->srq_tbl_lock, flags);
229 	dev->srq_tbl[srq->srq_handle] = NULL;
230 	spin_unlock_irqrestore(&dev->srq_tbl_lock, flags);
231 
232 	if (refcount_dec_and_test(&srq->refcnt))
233 		complete(&srq->free);
234 	wait_for_completion(&srq->free);
235 
236 	/* There is no support for kernel clients, so this is safe. */
237 	ib_umem_release(srq->umem);
238 
239 	pvrdma_page_dir_cleanup(dev, &srq->pdir);
240 
241 	kfree(srq);
242 
243 	atomic_dec(&dev->num_srqs);
244 }
245 
246 /**
247  * pvrdma_destroy_srq - destroy shared receive queue
248  * @srq: the shared receive queue to destroy
249  *
250  * @return: 0 for success.
251  */
252 int pvrdma_destroy_srq(struct ib_srq *srq)
253 {
254 	struct pvrdma_srq *vsrq = to_vsrq(srq);
255 	union pvrdma_cmd_req req;
256 	struct pvrdma_cmd_destroy_srq *cmd = &req.destroy_srq;
257 	struct pvrdma_dev *dev = to_vdev(srq->device);
258 	int ret;
259 
260 	memset(cmd, 0, sizeof(*cmd));
261 	cmd->hdr.cmd = PVRDMA_CMD_DESTROY_SRQ;
262 	cmd->srq_handle = vsrq->srq_handle;
263 
264 	ret = pvrdma_cmd_post(dev, &req, NULL, 0);
265 	if (ret < 0)
266 		dev_warn(&dev->pdev->dev,
267 			 "destroy shared receive queue failed, error: %d\n",
268 			 ret);
269 
270 	pvrdma_free_srq(dev, vsrq);
271 
272 	return 0;
273 }
274 
275 /**
276  * pvrdma_modify_srq - modify shared receive queue attributes
277  * @ibsrq: the shared receive queue to modify
278  * @attr: the shared receive queue's new attributes
279  * @attr_mask: attributes mask
280  * @udata: user data
281  *
282  * @returns 0 on success, otherwise returns an errno.
283  */
284 int pvrdma_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
285 		      enum ib_srq_attr_mask attr_mask, struct ib_udata *udata)
286 {
287 	struct pvrdma_srq *vsrq = to_vsrq(ibsrq);
288 	union pvrdma_cmd_req req;
289 	struct pvrdma_cmd_modify_srq *cmd = &req.modify_srq;
290 	struct pvrdma_dev *dev = to_vdev(ibsrq->device);
291 	int ret;
292 
293 	/* Only support SRQ limit. */
294 	if (!(attr_mask & IB_SRQ_LIMIT))
295 		return -EINVAL;
296 
297 	memset(cmd, 0, sizeof(*cmd));
298 	cmd->hdr.cmd = PVRDMA_CMD_MODIFY_SRQ;
299 	cmd->srq_handle = vsrq->srq_handle;
300 	cmd->attrs.srq_limit = attr->srq_limit;
301 	cmd->attr_mask = attr_mask;
302 
303 	ret = pvrdma_cmd_post(dev, &req, NULL, 0);
304 	if (ret < 0) {
305 		dev_warn(&dev->pdev->dev,
306 			 "could not modify shared receive queue, error: %d\n",
307 			 ret);
308 
309 		return -EINVAL;
310 	}
311 
312 	return ret;
313 }
314