xref: /openbmc/linux/drivers/infiniband/sw/rdmavt/srq.c (revision 65844828)
1 // SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
2 /*
3  * Copyright(c) 2016 Intel Corporation.
4  */
5 
6 #include <linux/err.h>
7 #include <linux/slab.h>
8 #include <linux/vmalloc.h>
9 #include <rdma/uverbs_ioctl.h>
10 
11 #include "srq.h"
12 #include "vt.h"
13 #include "qp.h"
14 /**
15  * rvt_driver_srq_init - init srq resources on a per driver basis
16  * @rdi: rvt dev structure
17  *
18  * Do any initialization needed when a driver registers with rdmavt.
19  */
20 void rvt_driver_srq_init(struct rvt_dev_info *rdi)
21 {
22 	spin_lock_init(&rdi->n_srqs_lock);
23 	rdi->n_srqs_allocated = 0;
24 }
25 
26 /**
27  * rvt_create_srq - create a shared receive queue
28  * @ibsrq: the protection domain of the SRQ to create
29  * @srq_init_attr: the attributes of the SRQ
30  * @udata: data from libibverbs when creating a user SRQ
31  *
32  * Return: 0 on success
33  */
34 int rvt_create_srq(struct ib_srq *ibsrq, struct ib_srq_init_attr *srq_init_attr,
35 		   struct ib_udata *udata)
36 {
37 	struct rvt_dev_info *dev = ib_to_rvt(ibsrq->device);
38 	struct rvt_srq *srq = ibsrq_to_rvtsrq(ibsrq);
39 	u32 sz;
40 	int ret;
41 
42 	if (srq_init_attr->srq_type != IB_SRQT_BASIC)
43 		return -EOPNOTSUPP;
44 
45 	if (srq_init_attr->attr.max_sge == 0 ||
46 	    srq_init_attr->attr.max_sge > dev->dparms.props.max_srq_sge ||
47 	    srq_init_attr->attr.max_wr == 0 ||
48 	    srq_init_attr->attr.max_wr > dev->dparms.props.max_srq_wr)
49 		return -EINVAL;
50 
51 	/*
52 	 * Need to use vmalloc() if we want to support large #s of entries.
53 	 */
54 	srq->rq.size = srq_init_attr->attr.max_wr + 1;
55 	srq->rq.max_sge = srq_init_attr->attr.max_sge;
56 	sz = sizeof(struct ib_sge) * srq->rq.max_sge +
57 		sizeof(struct rvt_rwqe);
58 	if (rvt_alloc_rq(&srq->rq, srq->rq.size * sz,
59 			 dev->dparms.node, udata)) {
60 		ret = -ENOMEM;
61 		goto bail_srq;
62 	}
63 
64 	/*
65 	 * Return the address of the RWQ as the offset to mmap.
66 	 * See rvt_mmap() for details.
67 	 */
68 	if (udata && udata->outlen >= sizeof(__u64)) {
69 		u32 s = sizeof(struct rvt_rwq) + srq->rq.size * sz;
70 
71 		srq->ip = rvt_create_mmap_info(dev, s, udata, srq->rq.wq);
72 		if (IS_ERR(srq->ip)) {
73 			ret = PTR_ERR(srq->ip);
74 			goto bail_wq;
75 		}
76 
77 		ret = ib_copy_to_udata(udata, &srq->ip->offset,
78 				       sizeof(srq->ip->offset));
79 		if (ret)
80 			goto bail_ip;
81 	}
82 
83 	/*
84 	 * ib_create_srq() will initialize srq->ibsrq.
85 	 */
86 	spin_lock_init(&srq->rq.lock);
87 	srq->limit = srq_init_attr->attr.srq_limit;
88 
89 	spin_lock(&dev->n_srqs_lock);
90 	if (dev->n_srqs_allocated == dev->dparms.props.max_srq) {
91 		spin_unlock(&dev->n_srqs_lock);
92 		ret = -ENOMEM;
93 		goto bail_ip;
94 	}
95 
96 	dev->n_srqs_allocated++;
97 	spin_unlock(&dev->n_srqs_lock);
98 
99 	if (srq->ip) {
100 		spin_lock_irq(&dev->pending_lock);
101 		list_add(&srq->ip->pending_mmaps, &dev->pending_mmaps);
102 		spin_unlock_irq(&dev->pending_lock);
103 	}
104 
105 	return 0;
106 
107 bail_ip:
108 	kfree(srq->ip);
109 bail_wq:
110 	rvt_free_rq(&srq->rq);
111 bail_srq:
112 	return ret;
113 }
114 
115 /**
116  * rvt_modify_srq - modify a shared receive queue
117  * @ibsrq: the SRQ to modify
118  * @attr: the new attributes of the SRQ
119  * @attr_mask: indicates which attributes to modify
120  * @udata: user data for libibverbs.so
121  *
122  * Return: 0 on success
123  */
124 int rvt_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
125 		   enum ib_srq_attr_mask attr_mask,
126 		   struct ib_udata *udata)
127 {
128 	struct rvt_srq *srq = ibsrq_to_rvtsrq(ibsrq);
129 	struct rvt_dev_info *dev = ib_to_rvt(ibsrq->device);
130 	struct rvt_rq tmp_rq = {};
131 	int ret = 0;
132 
133 	if (attr_mask & IB_SRQ_MAX_WR) {
134 		struct rvt_krwq *okwq = NULL;
135 		struct rvt_rwq *owq = NULL;
136 		struct rvt_rwqe *p;
137 		u32 sz, size, n, head, tail;
138 
139 		/* Check that the requested sizes are below the limits. */
140 		if ((attr->max_wr > dev->dparms.props.max_srq_wr) ||
141 		    ((attr_mask & IB_SRQ_LIMIT) ?
142 		     attr->srq_limit : srq->limit) > attr->max_wr)
143 			return -EINVAL;
144 		sz = sizeof(struct rvt_rwqe) +
145 			srq->rq.max_sge * sizeof(struct ib_sge);
146 		size = attr->max_wr + 1;
147 		if (rvt_alloc_rq(&tmp_rq, size * sz, dev->dparms.node,
148 				 udata))
149 			return -ENOMEM;
150 		/* Check that we can write the offset to mmap. */
151 		if (udata && udata->inlen >= sizeof(__u64)) {
152 			__u64 offset_addr;
153 			__u64 offset = 0;
154 
155 			ret = ib_copy_from_udata(&offset_addr, udata,
156 						 sizeof(offset_addr));
157 			if (ret)
158 				goto bail_free;
159 			udata->outbuf = (void __user *)
160 					(unsigned long)offset_addr;
161 			ret = ib_copy_to_udata(udata, &offset,
162 					       sizeof(offset));
163 			if (ret)
164 				goto bail_free;
165 		}
166 
167 		spin_lock_irq(&srq->rq.kwq->c_lock);
168 		/*
169 		 * validate head and tail pointer values and compute
170 		 * the number of remaining WQEs.
171 		 */
172 		if (udata) {
173 			owq = srq->rq.wq;
174 			head = RDMA_READ_UAPI_ATOMIC(owq->head);
175 			tail = RDMA_READ_UAPI_ATOMIC(owq->tail);
176 		} else {
177 			okwq = srq->rq.kwq;
178 			head = okwq->head;
179 			tail = okwq->tail;
180 		}
181 		if (head >= srq->rq.size || tail >= srq->rq.size) {
182 			ret = -EINVAL;
183 			goto bail_unlock;
184 		}
185 		n = head;
186 		if (n < tail)
187 			n += srq->rq.size - tail;
188 		else
189 			n -= tail;
190 		if (size <= n) {
191 			ret = -EINVAL;
192 			goto bail_unlock;
193 		}
194 		n = 0;
195 		p = tmp_rq.kwq->curr_wq;
196 		while (tail != head) {
197 			struct rvt_rwqe *wqe;
198 			int i;
199 
200 			wqe = rvt_get_rwqe_ptr(&srq->rq, tail);
201 			p->wr_id = wqe->wr_id;
202 			p->num_sge = wqe->num_sge;
203 			for (i = 0; i < wqe->num_sge; i++)
204 				p->sg_list[i] = wqe->sg_list[i];
205 			n++;
206 			p = (struct rvt_rwqe *)((char *)p + sz);
207 			if (++tail >= srq->rq.size)
208 				tail = 0;
209 		}
210 		srq->rq.kwq = tmp_rq.kwq;
211 		if (udata) {
212 			srq->rq.wq = tmp_rq.wq;
213 			RDMA_WRITE_UAPI_ATOMIC(tmp_rq.wq->head, n);
214 			RDMA_WRITE_UAPI_ATOMIC(tmp_rq.wq->tail, 0);
215 		} else {
216 			tmp_rq.kwq->head = n;
217 			tmp_rq.kwq->tail = 0;
218 		}
219 		srq->rq.size = size;
220 		if (attr_mask & IB_SRQ_LIMIT)
221 			srq->limit = attr->srq_limit;
222 		spin_unlock_irq(&srq->rq.kwq->c_lock);
223 
224 		vfree(owq);
225 		kvfree(okwq);
226 
227 		if (srq->ip) {
228 			struct rvt_mmap_info *ip = srq->ip;
229 			struct rvt_dev_info *dev = ib_to_rvt(srq->ibsrq.device);
230 			u32 s = sizeof(struct rvt_rwq) + size * sz;
231 
232 			rvt_update_mmap_info(dev, ip, s, tmp_rq.wq);
233 
234 			/*
235 			 * Return the offset to mmap.
236 			 * See rvt_mmap() for details.
237 			 */
238 			if (udata && udata->inlen >= sizeof(__u64)) {
239 				ret = ib_copy_to_udata(udata, &ip->offset,
240 						       sizeof(ip->offset));
241 				if (ret)
242 					return ret;
243 			}
244 
245 			/*
246 			 * Put user mapping info onto the pending list
247 			 * unless it already is on the list.
248 			 */
249 			spin_lock_irq(&dev->pending_lock);
250 			if (list_empty(&ip->pending_mmaps))
251 				list_add(&ip->pending_mmaps,
252 					 &dev->pending_mmaps);
253 			spin_unlock_irq(&dev->pending_lock);
254 		}
255 	} else if (attr_mask & IB_SRQ_LIMIT) {
256 		spin_lock_irq(&srq->rq.kwq->c_lock);
257 		if (attr->srq_limit >= srq->rq.size)
258 			ret = -EINVAL;
259 		else
260 			srq->limit = attr->srq_limit;
261 		spin_unlock_irq(&srq->rq.kwq->c_lock);
262 	}
263 	return ret;
264 
265 bail_unlock:
266 	spin_unlock_irq(&srq->rq.kwq->c_lock);
267 bail_free:
268 	rvt_free_rq(&tmp_rq);
269 	return ret;
270 }
271 
272 /**
273  * rvt_query_srq - query srq data
274  * @ibsrq: srq to query
275  * @attr: return info in attr
276  *
277  * Return: always 0
278  */
279 int rvt_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr)
280 {
281 	struct rvt_srq *srq = ibsrq_to_rvtsrq(ibsrq);
282 
283 	attr->max_wr = srq->rq.size - 1;
284 	attr->max_sge = srq->rq.max_sge;
285 	attr->srq_limit = srq->limit;
286 	return 0;
287 }
288 
289 /**
290  * rvt_destroy_srq - destory an srq
291  * @ibsrq: srq object to destroy
292  * @udata: user data for libibverbs.so
293  */
294 int rvt_destroy_srq(struct ib_srq *ibsrq, struct ib_udata *udata)
295 {
296 	struct rvt_srq *srq = ibsrq_to_rvtsrq(ibsrq);
297 	struct rvt_dev_info *dev = ib_to_rvt(ibsrq->device);
298 
299 	spin_lock(&dev->n_srqs_lock);
300 	dev->n_srqs_allocated--;
301 	spin_unlock(&dev->n_srqs_lock);
302 	if (srq->ip)
303 		kref_put(&srq->ip->ref, rvt_release_mmap_info);
304 	kvfree(srq->rq.kwq);
305 	return 0;
306 }
307