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 int pvrdma_post_srq_recv(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
56 			 struct ib_recv_wr **bad_wr)
57 {
58 	/* No support for kernel clients. */
59 	return -EOPNOTSUPP;
60 }
61 
62 /**
63  * pvrdma_query_srq - query shared receive queue
64  * @ibsrq: the shared receive queue to query
65  * @srq_attr: attributes to query and return to client
66  *
67  * @return: 0 for success, otherwise returns an errno.
68  */
69 int pvrdma_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *srq_attr)
70 {
71 	struct pvrdma_dev *dev = to_vdev(ibsrq->device);
72 	struct pvrdma_srq *srq = to_vsrq(ibsrq);
73 	union pvrdma_cmd_req req;
74 	union pvrdma_cmd_resp rsp;
75 	struct pvrdma_cmd_query_srq *cmd = &req.query_srq;
76 	struct pvrdma_cmd_query_srq_resp *resp = &rsp.query_srq_resp;
77 	int ret;
78 
79 	memset(cmd, 0, sizeof(*cmd));
80 	cmd->hdr.cmd = PVRDMA_CMD_QUERY_SRQ;
81 	cmd->srq_handle = srq->srq_handle;
82 
83 	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_QUERY_SRQ_RESP);
84 	if (ret < 0) {
85 		dev_warn(&dev->pdev->dev,
86 			 "could not query shared receive queue, error: %d\n",
87 			 ret);
88 		return -EINVAL;
89 	}
90 
91 	srq_attr->srq_limit = resp->attrs.srq_limit;
92 	srq_attr->max_wr = resp->attrs.max_wr;
93 	srq_attr->max_sge = resp->attrs.max_sge;
94 
95 	return 0;
96 }
97 
98 /**
99  * pvrdma_create_srq - create shared receive queue
100  * @pd: protection domain
101  * @init_attr: shared receive queue attributes
102  * @udata: user data
103  *
104  * @return: the ib_srq pointer on success, otherwise returns an errno.
105  */
106 struct ib_srq *pvrdma_create_srq(struct ib_pd *pd,
107 				 struct ib_srq_init_attr *init_attr,
108 				 struct ib_udata *udata)
109 {
110 	struct pvrdma_srq *srq = NULL;
111 	struct pvrdma_dev *dev = to_vdev(pd->device);
112 	union pvrdma_cmd_req req;
113 	union pvrdma_cmd_resp rsp;
114 	struct pvrdma_cmd_create_srq *cmd = &req.create_srq;
115 	struct pvrdma_cmd_create_srq_resp *resp = &rsp.create_srq_resp;
116 	struct pvrdma_create_srq_resp srq_resp = {0};
117 	struct pvrdma_create_srq ucmd;
118 	unsigned long flags;
119 	int ret;
120 
121 	if (!(pd->uobject && udata)) {
122 		/* No support for kernel clients. */
123 		dev_warn(&dev->pdev->dev,
124 			 "no shared receive queue support for kernel client\n");
125 		return ERR_PTR(-EOPNOTSUPP);
126 	}
127 
128 	if (init_attr->srq_type != IB_SRQT_BASIC) {
129 		dev_warn(&dev->pdev->dev,
130 			 "shared receive queue type %d not supported\n",
131 			 init_attr->srq_type);
132 		return ERR_PTR(-EINVAL);
133 	}
134 
135 	if (init_attr->attr.max_wr  > dev->dsr->caps.max_srq_wr ||
136 	    init_attr->attr.max_sge > dev->dsr->caps.max_srq_sge) {
137 		dev_warn(&dev->pdev->dev,
138 			 "shared receive queue size invalid\n");
139 		return ERR_PTR(-EINVAL);
140 	}
141 
142 	if (!atomic_add_unless(&dev->num_srqs, 1, dev->dsr->caps.max_srq))
143 		return ERR_PTR(-ENOMEM);
144 
145 	srq = kmalloc(sizeof(*srq), GFP_KERNEL);
146 	if (!srq) {
147 		ret = -ENOMEM;
148 		goto err_srq;
149 	}
150 
151 	spin_lock_init(&srq->lock);
152 	refcount_set(&srq->refcnt, 1);
153 	init_completion(&srq->free);
154 
155 	dev_dbg(&dev->pdev->dev,
156 		"create shared receive queue from user space\n");
157 
158 	if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd))) {
159 		ret = -EFAULT;
160 		goto err_srq;
161 	}
162 
163 	srq->umem = ib_umem_get(pd->uobject->context,
164 				ucmd.buf_addr,
165 				ucmd.buf_size, 0, 0);
166 	if (IS_ERR(srq->umem)) {
167 		ret = PTR_ERR(srq->umem);
168 		goto err_srq;
169 	}
170 
171 	srq->npages = ib_umem_page_count(srq->umem);
172 
173 	if (srq->npages < 0 || srq->npages > PVRDMA_PAGE_DIR_MAX_PAGES) {
174 		dev_warn(&dev->pdev->dev,
175 			 "overflow pages in shared receive queue\n");
176 		ret = -EINVAL;
177 		goto err_umem;
178 	}
179 
180 	ret = pvrdma_page_dir_init(dev, &srq->pdir, srq->npages, false);
181 	if (ret) {
182 		dev_warn(&dev->pdev->dev,
183 			 "could not allocate page directory\n");
184 		goto err_umem;
185 	}
186 
187 	pvrdma_page_dir_insert_umem(&srq->pdir, srq->umem, 0);
188 
189 	memset(cmd, 0, sizeof(*cmd));
190 	cmd->hdr.cmd = PVRDMA_CMD_CREATE_SRQ;
191 	cmd->srq_type = init_attr->srq_type;
192 	cmd->nchunks = srq->npages;
193 	cmd->pd_handle = to_vpd(pd)->pd_handle;
194 	cmd->attrs.max_wr = init_attr->attr.max_wr;
195 	cmd->attrs.max_sge = init_attr->attr.max_sge;
196 	cmd->attrs.srq_limit = init_attr->attr.srq_limit;
197 	cmd->pdir_dma = srq->pdir.dir_dma;
198 
199 	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_SRQ_RESP);
200 	if (ret < 0) {
201 		dev_warn(&dev->pdev->dev,
202 			 "could not create shared receive queue, error: %d\n",
203 			 ret);
204 		goto err_page_dir;
205 	}
206 
207 	srq->srq_handle = resp->srqn;
208 	srq_resp.srqn = resp->srqn;
209 	spin_lock_irqsave(&dev->srq_tbl_lock, flags);
210 	dev->srq_tbl[srq->srq_handle % dev->dsr->caps.max_srq] = srq;
211 	spin_unlock_irqrestore(&dev->srq_tbl_lock, flags);
212 
213 	/* Copy udata back. */
214 	if (ib_copy_to_udata(udata, &srq_resp, sizeof(srq_resp))) {
215 		dev_warn(&dev->pdev->dev, "failed to copy back udata\n");
216 		pvrdma_destroy_srq(&srq->ibsrq);
217 		return ERR_PTR(-EINVAL);
218 	}
219 
220 	return &srq->ibsrq;
221 
222 err_page_dir:
223 	pvrdma_page_dir_cleanup(dev, &srq->pdir);
224 err_umem:
225 	ib_umem_release(srq->umem);
226 err_srq:
227 	kfree(srq);
228 	atomic_dec(&dev->num_srqs);
229 
230 	return ERR_PTR(ret);
231 }
232 
233 static void pvrdma_free_srq(struct pvrdma_dev *dev, struct pvrdma_srq *srq)
234 {
235 	unsigned long flags;
236 
237 	spin_lock_irqsave(&dev->srq_tbl_lock, flags);
238 	dev->srq_tbl[srq->srq_handle] = NULL;
239 	spin_unlock_irqrestore(&dev->srq_tbl_lock, flags);
240 
241 	if (refcount_dec_and_test(&srq->refcnt))
242 		complete(&srq->free);
243 	wait_for_completion(&srq->free);
244 
245 	/* There is no support for kernel clients, so this is safe. */
246 	ib_umem_release(srq->umem);
247 
248 	pvrdma_page_dir_cleanup(dev, &srq->pdir);
249 
250 	kfree(srq);
251 
252 	atomic_dec(&dev->num_srqs);
253 }
254 
255 /**
256  * pvrdma_destroy_srq - destroy shared receive queue
257  * @srq: the shared receive queue to destroy
258  *
259  * @return: 0 for success.
260  */
261 int pvrdma_destroy_srq(struct ib_srq *srq)
262 {
263 	struct pvrdma_srq *vsrq = to_vsrq(srq);
264 	union pvrdma_cmd_req req;
265 	struct pvrdma_cmd_destroy_srq *cmd = &req.destroy_srq;
266 	struct pvrdma_dev *dev = to_vdev(srq->device);
267 	int ret;
268 
269 	memset(cmd, 0, sizeof(*cmd));
270 	cmd->hdr.cmd = PVRDMA_CMD_DESTROY_SRQ;
271 	cmd->srq_handle = vsrq->srq_handle;
272 
273 	ret = pvrdma_cmd_post(dev, &req, NULL, 0);
274 	if (ret < 0)
275 		dev_warn(&dev->pdev->dev,
276 			 "destroy shared receive queue failed, error: %d\n",
277 			 ret);
278 
279 	pvrdma_free_srq(dev, vsrq);
280 
281 	return 0;
282 }
283 
284 /**
285  * pvrdma_modify_srq - modify shared receive queue attributes
286  * @ibsrq: the shared receive queue to modify
287  * @attr: the shared receive queue's new attributes
288  * @attr_mask: attributes mask
289  * @udata: user data
290  *
291  * @returns 0 on success, otherwise returns an errno.
292  */
293 int pvrdma_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
294 		      enum ib_srq_attr_mask attr_mask, struct ib_udata *udata)
295 {
296 	struct pvrdma_srq *vsrq = to_vsrq(ibsrq);
297 	union pvrdma_cmd_req req;
298 	struct pvrdma_cmd_modify_srq *cmd = &req.modify_srq;
299 	struct pvrdma_dev *dev = to_vdev(ibsrq->device);
300 	int ret;
301 
302 	/* Only support SRQ limit. */
303 	if (!(attr_mask & IB_SRQ_LIMIT))
304 		return -EINVAL;
305 
306 	memset(cmd, 0, sizeof(*cmd));
307 	cmd->hdr.cmd = PVRDMA_CMD_MODIFY_SRQ;
308 	cmd->srq_handle = vsrq->srq_handle;
309 	cmd->attrs.srq_limit = attr->srq_limit;
310 	cmd->attr_mask = attr_mask;
311 
312 	ret = pvrdma_cmd_post(dev, &req, NULL, 0);
313 	if (ret < 0) {
314 		dev_warn(&dev->pdev->dev,
315 			 "could not modify shared receive queue, error: %d\n",
316 			 ret);
317 
318 		return -EINVAL;
319 	}
320 
321 	return ret;
322 }
323