xref: /openbmc/linux/drivers/infiniband/sw/rdmavt/srq.c (revision b78412b8)
1 /*
2  * Copyright(c) 2016 Intel Corporation.
3  *
4  * This file is provided under a dual BSD/GPLv2 license.  When using or
5  * redistributing this file, you may do so under either license.
6  *
7  * GPL LICENSE SUMMARY
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * BSD LICENSE
19  *
20  * Redistribution and use in source and binary forms, with or without
21  * modification, are permitted provided that the following conditions
22  * are met:
23  *
24  *  - Redistributions of source code must retain the above copyright
25  *    notice, this list of conditions and the following disclaimer.
26  *  - Redistributions in binary form must reproduce the above copyright
27  *    notice, this list of conditions and the following disclaimer in
28  *    the documentation and/or other materials provided with the
29  *    distribution.
30  *  - Neither the name of Intel Corporation nor the names of its
31  *    contributors may be used to endorse or promote products derived
32  *    from this software without specific prior written permission.
33  *
34  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45  *
46  */
47 
48 #include <linux/err.h>
49 #include <linux/slab.h>
50 #include <linux/vmalloc.h>
51 
52 #include "srq.h"
53 #include "vt.h"
54 
55 /**
56  * rvt_driver_srq_init - init srq resources on a per driver basis
57  * @rdi: rvt dev structure
58  *
59  * Do any initialization needed when a driver registers with rdmavt.
60  */
61 void rvt_driver_srq_init(struct rvt_dev_info *rdi)
62 {
63 	spin_lock_init(&rdi->n_srqs_lock);
64 	rdi->n_srqs_allocated = 0;
65 }
66 
67 /**
68  * rvt_create_srq - create a shared receive queue
69  * @ibpd: the protection domain of the SRQ to create
70  * @srq_init_attr: the attributes of the SRQ
71  * @udata: data from libibverbs when creating a user SRQ
72  *
73  * Return: Allocated srq object
74  */
75 struct ib_srq *rvt_create_srq(struct ib_pd *ibpd,
76 			      struct ib_srq_init_attr *srq_init_attr,
77 			      struct ib_udata *udata)
78 {
79 	struct rvt_dev_info *dev = ib_to_rvt(ibpd->device);
80 	struct rvt_srq *srq;
81 	u32 sz;
82 	struct ib_srq *ret;
83 
84 	if (srq_init_attr->srq_type != IB_SRQT_BASIC)
85 		return ERR_PTR(-ENOSYS);
86 
87 	if (srq_init_attr->attr.max_sge == 0 ||
88 	    srq_init_attr->attr.max_sge > dev->dparms.props.max_srq_sge ||
89 	    srq_init_attr->attr.max_wr == 0 ||
90 	    srq_init_attr->attr.max_wr > dev->dparms.props.max_srq_wr)
91 		return ERR_PTR(-EINVAL);
92 
93 	srq = kmalloc(sizeof(*srq), GFP_KERNEL);
94 	if (!srq)
95 		return ERR_PTR(-ENOMEM);
96 
97 	/*
98 	 * Need to use vmalloc() if we want to support large #s of entries.
99 	 */
100 	srq->rq.size = srq_init_attr->attr.max_wr + 1;
101 	srq->rq.max_sge = srq_init_attr->attr.max_sge;
102 	sz = sizeof(struct ib_sge) * srq->rq.max_sge +
103 		sizeof(struct rvt_rwqe);
104 	srq->rq.wq = vmalloc_user(sizeof(struct rvt_rwq) + srq->rq.size * sz);
105 	if (!srq->rq.wq) {
106 		ret = ERR_PTR(-ENOMEM);
107 		goto bail_srq;
108 	}
109 
110 	/*
111 	 * Return the address of the RWQ as the offset to mmap.
112 	 * See rvt_mmap() for details.
113 	 */
114 	if (udata && udata->outlen >= sizeof(__u64)) {
115 		int err;
116 		u32 s = sizeof(struct rvt_rwq) + srq->rq.size * sz;
117 
118 		srq->ip =
119 		    rvt_create_mmap_info(dev, s, ibpd->uobject->context,
120 					 srq->rq.wq);
121 		if (!srq->ip) {
122 			ret = ERR_PTR(-ENOMEM);
123 			goto bail_wq;
124 		}
125 
126 		err = ib_copy_to_udata(udata, &srq->ip->offset,
127 				       sizeof(srq->ip->offset));
128 		if (err) {
129 			ret = ERR_PTR(err);
130 			goto bail_ip;
131 		}
132 	} else {
133 		srq->ip = NULL;
134 	}
135 
136 	/*
137 	 * ib_create_srq() will initialize srq->ibsrq.
138 	 */
139 	spin_lock_init(&srq->rq.lock);
140 	srq->rq.wq->head = 0;
141 	srq->rq.wq->tail = 0;
142 	srq->limit = srq_init_attr->attr.srq_limit;
143 
144 	spin_lock(&dev->n_srqs_lock);
145 	if (dev->n_srqs_allocated == dev->dparms.props.max_srq) {
146 		spin_unlock(&dev->n_srqs_lock);
147 		ret = ERR_PTR(-ENOMEM);
148 		goto bail_ip;
149 	}
150 
151 	dev->n_srqs_allocated++;
152 	spin_unlock(&dev->n_srqs_lock);
153 
154 	if (srq->ip) {
155 		spin_lock_irq(&dev->pending_lock);
156 		list_add(&srq->ip->pending_mmaps, &dev->pending_mmaps);
157 		spin_unlock_irq(&dev->pending_lock);
158 	}
159 
160 	return &srq->ibsrq;
161 
162 bail_ip:
163 	kfree(srq->ip);
164 bail_wq:
165 	vfree(srq->rq.wq);
166 bail_srq:
167 	kfree(srq);
168 	return ret;
169 }
170 
171 /**
172  * rvt_modify_srq - modify a shared receive queue
173  * @ibsrq: the SRQ to modify
174  * @attr: the new attributes of the SRQ
175  * @attr_mask: indicates which attributes to modify
176  * @udata: user data for libibverbs.so
177  *
178  * Return: 0 on success
179  */
180 int rvt_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
181 		   enum ib_srq_attr_mask attr_mask,
182 		   struct ib_udata *udata)
183 {
184 	struct rvt_srq *srq = ibsrq_to_rvtsrq(ibsrq);
185 	struct rvt_dev_info *dev = ib_to_rvt(ibsrq->device);
186 	struct rvt_rwq *wq;
187 	int ret = 0;
188 
189 	if (attr_mask & IB_SRQ_MAX_WR) {
190 		struct rvt_rwq *owq;
191 		struct rvt_rwqe *p;
192 		u32 sz, size, n, head, tail;
193 
194 		/* Check that the requested sizes are below the limits. */
195 		if ((attr->max_wr > dev->dparms.props.max_srq_wr) ||
196 		    ((attr_mask & IB_SRQ_LIMIT) ?
197 		     attr->srq_limit : srq->limit) > attr->max_wr)
198 			return -EINVAL;
199 
200 		sz = sizeof(struct rvt_rwqe) +
201 			srq->rq.max_sge * sizeof(struct ib_sge);
202 		size = attr->max_wr + 1;
203 		wq = vmalloc_user(sizeof(struct rvt_rwq) + size * sz);
204 		if (!wq)
205 			return -ENOMEM;
206 
207 		/* Check that we can write the offset to mmap. */
208 		if (udata && udata->inlen >= sizeof(__u64)) {
209 			__u64 offset_addr;
210 			__u64 offset = 0;
211 
212 			ret = ib_copy_from_udata(&offset_addr, udata,
213 						 sizeof(offset_addr));
214 			if (ret)
215 				goto bail_free;
216 			udata->outbuf = (void __user *)
217 					(unsigned long)offset_addr;
218 			ret = ib_copy_to_udata(udata, &offset,
219 					       sizeof(offset));
220 			if (ret)
221 				goto bail_free;
222 		}
223 
224 		spin_lock_irq(&srq->rq.lock);
225 		/*
226 		 * validate head and tail pointer values and compute
227 		 * the number of remaining WQEs.
228 		 */
229 		owq = srq->rq.wq;
230 		head = owq->head;
231 		tail = owq->tail;
232 		if (head >= srq->rq.size || tail >= srq->rq.size) {
233 			ret = -EINVAL;
234 			goto bail_unlock;
235 		}
236 		n = head;
237 		if (n < tail)
238 			n += srq->rq.size - tail;
239 		else
240 			n -= tail;
241 		if (size <= n) {
242 			ret = -EINVAL;
243 			goto bail_unlock;
244 		}
245 		n = 0;
246 		p = wq->wq;
247 		while (tail != head) {
248 			struct rvt_rwqe *wqe;
249 			int i;
250 
251 			wqe = rvt_get_rwqe_ptr(&srq->rq, tail);
252 			p->wr_id = wqe->wr_id;
253 			p->num_sge = wqe->num_sge;
254 			for (i = 0; i < wqe->num_sge; i++)
255 				p->sg_list[i] = wqe->sg_list[i];
256 			n++;
257 			p = (struct rvt_rwqe *)((char *)p + sz);
258 			if (++tail >= srq->rq.size)
259 				tail = 0;
260 		}
261 		srq->rq.wq = wq;
262 		srq->rq.size = size;
263 		wq->head = n;
264 		wq->tail = 0;
265 		if (attr_mask & IB_SRQ_LIMIT)
266 			srq->limit = attr->srq_limit;
267 		spin_unlock_irq(&srq->rq.lock);
268 
269 		vfree(owq);
270 
271 		if (srq->ip) {
272 			struct rvt_mmap_info *ip = srq->ip;
273 			struct rvt_dev_info *dev = ib_to_rvt(srq->ibsrq.device);
274 			u32 s = sizeof(struct rvt_rwq) + size * sz;
275 
276 			rvt_update_mmap_info(dev, ip, s, wq);
277 
278 			/*
279 			 * Return the offset to mmap.
280 			 * See rvt_mmap() for details.
281 			 */
282 			if (udata && udata->inlen >= sizeof(__u64)) {
283 				ret = ib_copy_to_udata(udata, &ip->offset,
284 						       sizeof(ip->offset));
285 				if (ret)
286 					return ret;
287 			}
288 
289 			/*
290 			 * Put user mapping info onto the pending list
291 			 * unless it already is on the list.
292 			 */
293 			spin_lock_irq(&dev->pending_lock);
294 			if (list_empty(&ip->pending_mmaps))
295 				list_add(&ip->pending_mmaps,
296 					 &dev->pending_mmaps);
297 			spin_unlock_irq(&dev->pending_lock);
298 		}
299 	} else if (attr_mask & IB_SRQ_LIMIT) {
300 		spin_lock_irq(&srq->rq.lock);
301 		if (attr->srq_limit >= srq->rq.size)
302 			ret = -EINVAL;
303 		else
304 			srq->limit = attr->srq_limit;
305 		spin_unlock_irq(&srq->rq.lock);
306 	}
307 	return ret;
308 
309 bail_unlock:
310 	spin_unlock_irq(&srq->rq.lock);
311 bail_free:
312 	vfree(wq);
313 	return ret;
314 }
315 
316 /** rvt_query_srq - query srq data
317  * @ibsrq: srq to query
318  * @attr: return info in attr
319  *
320  * Return: always 0
321  */
322 int rvt_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr)
323 {
324 	struct rvt_srq *srq = ibsrq_to_rvtsrq(ibsrq);
325 
326 	attr->max_wr = srq->rq.size - 1;
327 	attr->max_sge = srq->rq.max_sge;
328 	attr->srq_limit = srq->limit;
329 	return 0;
330 }
331 
332 /**
333  * rvt_destroy_srq - destory an srq
334  * @ibsrq: srq object to destroy
335  *
336  * Return always 0
337  */
338 int rvt_destroy_srq(struct ib_srq *ibsrq)
339 {
340 	struct rvt_srq *srq = ibsrq_to_rvtsrq(ibsrq);
341 	struct rvt_dev_info *dev = ib_to_rvt(ibsrq->device);
342 
343 	spin_lock(&dev->n_srqs_lock);
344 	dev->n_srqs_allocated--;
345 	spin_unlock(&dev->n_srqs_lock);
346 	if (srq->ip)
347 		kref_put(&srq->ip->ref, rvt_release_mmap_info);
348 	else
349 		vfree(srq->rq.wq);
350 	kfree(srq);
351 
352 	return 0;
353 }
354