Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / infiniband / hw / ipath / ipath_srq.c
1 /*
2  * Copyright (c) 2006, 2007, 2008 QLogic Corporation. All rights reserved.
3  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *        copyright notice, this list of conditions and the following
17  *        disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *        copyright notice, this list of conditions and the following
21  *        disclaimer in the documentation and/or other materials
22  *        provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33
34 #include <linux/err.h>
35 #include <linux/slab.h>
36 #include <linux/vmalloc.h>
37
38 #include "ipath_verbs.h"
39
40 /**
41  * ipath_post_srq_receive - post a receive on a shared receive queue
42  * @ibsrq: the SRQ to post the receive on
43  * @wr: the list of work requests to post
44  * @bad_wr: the first WR to cause a problem is put here
45  *
46  * This may be called from interrupt context.
47  */
48 int ipath_post_srq_receive(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
49                            struct ib_recv_wr **bad_wr)
50 {
51         struct ipath_srq *srq = to_isrq(ibsrq);
52         struct ipath_rwq *wq;
53         unsigned long flags;
54         int ret;
55
56         for (; wr; wr = wr->next) {
57                 struct ipath_rwqe *wqe;
58                 u32 next;
59                 int i;
60
61                 if ((unsigned) wr->num_sge > srq->rq.max_sge) {
62                         *bad_wr = wr;
63                         ret = -EINVAL;
64                         goto bail;
65                 }
66
67                 spin_lock_irqsave(&srq->rq.lock, flags);
68                 wq = srq->rq.wq;
69                 next = wq->head + 1;
70                 if (next >= srq->rq.size)
71                         next = 0;
72                 if (next == wq->tail) {
73                         spin_unlock_irqrestore(&srq->rq.lock, flags);
74                         *bad_wr = wr;
75                         ret = -ENOMEM;
76                         goto bail;
77                 }
78
79                 wqe = get_rwqe_ptr(&srq->rq, wq->head);
80                 wqe->wr_id = wr->wr_id;
81                 wqe->num_sge = wr->num_sge;
82                 for (i = 0; i < wr->num_sge; i++)
83                         wqe->sg_list[i] = wr->sg_list[i];
84                 /* Make sure queue entry is written before the head index. */
85                 smp_wmb();
86                 wq->head = next;
87                 spin_unlock_irqrestore(&srq->rq.lock, flags);
88         }
89         ret = 0;
90
91 bail:
92         return ret;
93 }
94
95 /**
96  * ipath_create_srq - create a shared receive queue
97  * @ibpd: the protection domain of the SRQ to create
98  * @srq_init_attr: the attributes of the SRQ
99  * @udata: data from libipathverbs when creating a user SRQ
100  */
101 struct ib_srq *ipath_create_srq(struct ib_pd *ibpd,
102                                 struct ib_srq_init_attr *srq_init_attr,
103                                 struct ib_udata *udata)
104 {
105         struct ipath_ibdev *dev = to_idev(ibpd->device);
106         struct ipath_srq *srq;
107         u32 sz;
108         struct ib_srq *ret;
109
110         if (srq_init_attr->srq_type != IB_SRQT_BASIC) {
111                 ret = ERR_PTR(-ENOSYS);
112                 goto done;
113         }
114
115         if (srq_init_attr->attr.max_wr == 0) {
116                 ret = ERR_PTR(-EINVAL);
117                 goto done;
118         }
119
120         if ((srq_init_attr->attr.max_sge > ib_ipath_max_srq_sges) ||
121             (srq_init_attr->attr.max_wr > ib_ipath_max_srq_wrs)) {
122                 ret = ERR_PTR(-EINVAL);
123                 goto done;
124         }
125
126         srq = kmalloc(sizeof(*srq), GFP_KERNEL);
127         if (!srq) {
128                 ret = ERR_PTR(-ENOMEM);
129                 goto done;
130         }
131
132         /*
133          * Need to use vmalloc() if we want to support large #s of entries.
134          */
135         srq->rq.size = srq_init_attr->attr.max_wr + 1;
136         srq->rq.max_sge = srq_init_attr->attr.max_sge;
137         sz = sizeof(struct ib_sge) * srq->rq.max_sge +
138                 sizeof(struct ipath_rwqe);
139         srq->rq.wq = vmalloc_user(sizeof(struct ipath_rwq) + srq->rq.size * sz);
140         if (!srq->rq.wq) {
141                 ret = ERR_PTR(-ENOMEM);
142                 goto bail_srq;
143         }
144
145         /*
146          * Return the address of the RWQ as the offset to mmap.
147          * See ipath_mmap() for details.
148          */
149         if (udata && udata->outlen >= sizeof(__u64)) {
150                 int err;
151                 u32 s = sizeof(struct ipath_rwq) + srq->rq.size * sz;
152
153                 srq->ip =
154                     ipath_create_mmap_info(dev, s,
155                                            ibpd->uobject->context,
156                                            srq->rq.wq);
157                 if (!srq->ip) {
158                         ret = ERR_PTR(-ENOMEM);
159                         goto bail_wq;
160                 }
161
162                 err = ib_copy_to_udata(udata, &srq->ip->offset,
163                                        sizeof(srq->ip->offset));
164                 if (err) {
165                         ret = ERR_PTR(err);
166                         goto bail_ip;
167                 }
168         } else
169                 srq->ip = NULL;
170
171         /*
172          * ib_create_srq() will initialize srq->ibsrq.
173          */
174         spin_lock_init(&srq->rq.lock);
175         srq->rq.wq->head = 0;
176         srq->rq.wq->tail = 0;
177         srq->limit = srq_init_attr->attr.srq_limit;
178
179         spin_lock(&dev->n_srqs_lock);
180         if (dev->n_srqs_allocated == ib_ipath_max_srqs) {
181                 spin_unlock(&dev->n_srqs_lock);
182                 ret = ERR_PTR(-ENOMEM);
183                 goto bail_ip;
184         }
185
186         dev->n_srqs_allocated++;
187         spin_unlock(&dev->n_srqs_lock);
188
189         if (srq->ip) {
190                 spin_lock_irq(&dev->pending_lock);
191                 list_add(&srq->ip->pending_mmaps, &dev->pending_mmaps);
192                 spin_unlock_irq(&dev->pending_lock);
193         }
194
195         ret = &srq->ibsrq;
196         goto done;
197
198 bail_ip:
199         kfree(srq->ip);
200 bail_wq:
201         vfree(srq->rq.wq);
202 bail_srq:
203         kfree(srq);
204 done:
205         return ret;
206 }
207
208 /**
209  * ipath_modify_srq - modify a shared receive queue
210  * @ibsrq: the SRQ to modify
211  * @attr: the new attributes of the SRQ
212  * @attr_mask: indicates which attributes to modify
213  * @udata: user data for ipathverbs.so
214  */
215 int ipath_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
216                      enum ib_srq_attr_mask attr_mask,
217                      struct ib_udata *udata)
218 {
219         struct ipath_srq *srq = to_isrq(ibsrq);
220         struct ipath_rwq *wq;
221         int ret = 0;
222
223         if (attr_mask & IB_SRQ_MAX_WR) {
224                 struct ipath_rwq *owq;
225                 struct ipath_rwqe *p;
226                 u32 sz, size, n, head, tail;
227
228                 /* Check that the requested sizes are below the limits. */
229                 if ((attr->max_wr > ib_ipath_max_srq_wrs) ||
230                     ((attr_mask & IB_SRQ_LIMIT) ?
231                      attr->srq_limit : srq->limit) > attr->max_wr) {
232                         ret = -EINVAL;
233                         goto bail;
234                 }
235
236                 sz = sizeof(struct ipath_rwqe) +
237                         srq->rq.max_sge * sizeof(struct ib_sge);
238                 size = attr->max_wr + 1;
239                 wq = vmalloc_user(sizeof(struct ipath_rwq) + size * sz);
240                 if (!wq) {
241                         ret = -ENOMEM;
242                         goto bail;
243                 }
244
245                 /* Check that we can write the offset to mmap. */
246                 if (udata && udata->inlen >= sizeof(__u64)) {
247                         __u64 offset_addr;
248                         __u64 offset = 0;
249
250                         ret = ib_copy_from_udata(&offset_addr, udata,
251                                                  sizeof(offset_addr));
252                         if (ret)
253                                 goto bail_free;
254                         udata->outbuf =
255                                 (void __user *) (unsigned long) offset_addr;
256                         ret = ib_copy_to_udata(udata, &offset,
257                                                sizeof(offset));
258                         if (ret)
259                                 goto bail_free;
260                 }
261
262                 spin_lock_irq(&srq->rq.lock);
263                 /*
264                  * validate head pointer value and compute
265                  * the number of remaining WQEs.
266                  */
267                 owq = srq->rq.wq;
268                 head = owq->head;
269                 if (head >= srq->rq.size)
270                         head = 0;
271                 tail = owq->tail;
272                 if (tail >= srq->rq.size)
273                         tail = 0;
274                 n = head;
275                 if (n < tail)
276                         n += srq->rq.size - tail;
277                 else
278                         n -= tail;
279                 if (size <= n) {
280                         ret = -EINVAL;
281                         goto bail_unlock;
282                 }
283                 n = 0;
284                 p = wq->wq;
285                 while (tail != head) {
286                         struct ipath_rwqe *wqe;
287                         int i;
288
289                         wqe = get_rwqe_ptr(&srq->rq, tail);
290                         p->wr_id = wqe->wr_id;
291                         p->num_sge = wqe->num_sge;
292                         for (i = 0; i < wqe->num_sge; i++)
293                                 p->sg_list[i] = wqe->sg_list[i];
294                         n++;
295                         p = (struct ipath_rwqe *)((char *) p + sz);
296                         if (++tail >= srq->rq.size)
297                                 tail = 0;
298                 }
299                 srq->rq.wq = wq;
300                 srq->rq.size = size;
301                 wq->head = n;
302                 wq->tail = 0;
303                 if (attr_mask & IB_SRQ_LIMIT)
304                         srq->limit = attr->srq_limit;
305                 spin_unlock_irq(&srq->rq.lock);
306
307                 vfree(owq);
308
309                 if (srq->ip) {
310                         struct ipath_mmap_info *ip = srq->ip;
311                         struct ipath_ibdev *dev = to_idev(srq->ibsrq.device);
312                         u32 s = sizeof(struct ipath_rwq) + size * sz;
313
314                         ipath_update_mmap_info(dev, ip, s, wq);
315
316                         /*
317                          * Return the offset to mmap.
318                          * See ipath_mmap() for details.
319                          */
320                         if (udata && udata->inlen >= sizeof(__u64)) {
321                                 ret = ib_copy_to_udata(udata, &ip->offset,
322                                                        sizeof(ip->offset));
323                                 if (ret)
324                                         goto bail;
325                         }
326
327                         spin_lock_irq(&dev->pending_lock);
328                         if (list_empty(&ip->pending_mmaps))
329                                 list_add(&ip->pending_mmaps,
330                                          &dev->pending_mmaps);
331                         spin_unlock_irq(&dev->pending_lock);
332                 }
333         } else if (attr_mask & IB_SRQ_LIMIT) {
334                 spin_lock_irq(&srq->rq.lock);
335                 if (attr->srq_limit >= srq->rq.size)
336                         ret = -EINVAL;
337                 else
338                         srq->limit = attr->srq_limit;
339                 spin_unlock_irq(&srq->rq.lock);
340         }
341         goto bail;
342
343 bail_unlock:
344         spin_unlock_irq(&srq->rq.lock);
345 bail_free:
346         vfree(wq);
347 bail:
348         return ret;
349 }
350
351 int ipath_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr)
352 {
353         struct ipath_srq *srq = to_isrq(ibsrq);
354
355         attr->max_wr = srq->rq.size - 1;
356         attr->max_sge = srq->rq.max_sge;
357         attr->srq_limit = srq->limit;
358         return 0;
359 }
360
361 /**
362  * ipath_destroy_srq - destroy a shared receive queue
363  * @ibsrq: the SRQ to destroy
364  */
365 int ipath_destroy_srq(struct ib_srq *ibsrq)
366 {
367         struct ipath_srq *srq = to_isrq(ibsrq);
368         struct ipath_ibdev *dev = to_idev(ibsrq->device);
369
370         spin_lock(&dev->n_srqs_lock);
371         dev->n_srqs_allocated--;
372         spin_unlock(&dev->n_srqs_lock);
373         if (srq->ip)
374                 kref_put(&srq->ip->ref, ipath_release_mmap_info);
375         else
376                 vfree(srq->rq.wq);
377         kfree(srq);
378
379         return 0;
380 }