Commit | Line | Data |
---|---|---|
fc79d4b1 TT |
1 | /* |
2 | * linux/fs/9p/trans_rdma.c | |
3 | * | |
4 | * RDMA transport layer based on the trans_fd.c implementation. | |
5 | * | |
6 | * Copyright (C) 2008 by Tom Tucker <tom@opengridcomputing.com> | |
7 | * Copyright (C) 2006 by Russ Cox <rsc@swtch.com> | |
8 | * Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net> | |
9 | * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com> | |
10 | * Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com> | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License version 2 | |
14 | * as published by the Free Software Foundation. | |
15 | * | |
16 | * This program is distributed in the hope that it will be useful, | |
17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
19 | * GNU General Public License for more details. | |
20 | * | |
21 | * You should have received a copy of the GNU General Public License | |
22 | * along with this program; if not, write to: | |
23 | * Free Software Foundation | |
24 | * 51 Franklin Street, Fifth Floor | |
25 | * Boston, MA 02111-1301 USA | |
26 | * | |
27 | */ | |
28 | ||
5d385153 JP |
29 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
30 | ||
fc79d4b1 TT |
31 | #include <linux/in.h> |
32 | #include <linux/module.h> | |
33 | #include <linux/net.h> | |
34 | #include <linux/ipv6.h> | |
35 | #include <linux/kthread.h> | |
36 | #include <linux/errno.h> | |
37 | #include <linux/kernel.h> | |
38 | #include <linux/un.h> | |
39 | #include <linux/uaccess.h> | |
40 | #include <linux/inet.h> | |
41 | #include <linux/idr.h> | |
42 | #include <linux/file.h> | |
43 | #include <linux/parser.h> | |
44 | #include <linux/semaphore.h> | |
5a0e3ad6 | 45 | #include <linux/slab.h> |
fc79d4b1 TT |
46 | #include <net/9p/9p.h> |
47 | #include <net/9p/client.h> | |
48 | #include <net/9p/transport.h> | |
49 | #include <rdma/ib_verbs.h> | |
50 | #include <rdma/rdma_cm.h> | |
fc79d4b1 TT |
51 | |
52 | #define P9_PORT 5640 | |
53 | #define P9_RDMA_SQ_DEPTH 32 | |
54 | #define P9_RDMA_RQ_DEPTH 32 | |
55 | #define P9_RDMA_SEND_SGE 4 | |
56 | #define P9_RDMA_RECV_SGE 4 | |
57 | #define P9_RDMA_IRD 0 | |
58 | #define P9_RDMA_ORD 0 | |
59 | #define P9_RDMA_TIMEOUT 30000 /* 30 seconds */ | |
3fcc62f4 | 60 | #define P9_RDMA_MAXSIZE (1024*1024) /* 1MB */ |
fc79d4b1 | 61 | |
fc79d4b1 TT |
62 | /** |
63 | * struct p9_trans_rdma - RDMA transport instance | |
64 | * | |
65 | * @state: tracks the transport state machine for connection setup and tear down | |
66 | * @cm_id: The RDMA CM ID | |
67 | * @pd: Protection Domain pointer | |
68 | * @qp: Queue Pair pointer | |
69 | * @cq: Completion Queue pointer | |
0e15597e | 70 | * @dm_mr: DMA Memory Region pointer |
fc79d4b1 TT |
71 | * @lkey: The local access only memory region key |
72 | * @timeout: Number of uSecs to wait for connection management events | |
73 | * @sq_depth: The depth of the Send Queue | |
74 | * @sq_sem: Semaphore for the SQ | |
75 | * @rq_depth: The depth of the Receive Queue. | |
fd453d0e | 76 | * @rq_sem: Semaphore for the RQ |
1cff3306 SD |
77 | * @excess_rc : Amount of posted Receive Contexts without a pending request. |
78 | * See rdma_request() | |
fc79d4b1 TT |
79 | * @addr: The remote peer's address |
80 | * @req_lock: Protects the active request list | |
fc79d4b1 TT |
81 | * @cm_done: Completion event for connection management tracking |
82 | */ | |
83 | struct p9_trans_rdma { | |
84 | enum { | |
85 | P9_RDMA_INIT, | |
86 | P9_RDMA_ADDR_RESOLVED, | |
87 | P9_RDMA_ROUTE_RESOLVED, | |
88 | P9_RDMA_CONNECTED, | |
89 | P9_RDMA_FLUSHING, | |
90 | P9_RDMA_CLOSING, | |
91 | P9_RDMA_CLOSED, | |
92 | } state; | |
93 | struct rdma_cm_id *cm_id; | |
94 | struct ib_pd *pd; | |
95 | struct ib_qp *qp; | |
96 | struct ib_cq *cq; | |
97 | struct ib_mr *dma_mr; | |
98 | u32 lkey; | |
99 | long timeout; | |
100 | int sq_depth; | |
101 | struct semaphore sq_sem; | |
102 | int rq_depth; | |
fd453d0e | 103 | struct semaphore rq_sem; |
1cff3306 | 104 | atomic_t excess_rc; |
fc79d4b1 TT |
105 | struct sockaddr_in addr; |
106 | spinlock_t req_lock; | |
107 | ||
108 | struct completion cm_done; | |
109 | }; | |
110 | ||
111 | /** | |
112 | * p9_rdma_context - Keeps track of in-process WR | |
113 | * | |
114 | * @wc_op: The original WR op for when the CQE completes in error. | |
115 | * @busa: Bus address to unmap when the WR completes | |
116 | * @req: Keeps track of requests (send) | |
117 | * @rc: Keepts track of replies (receive) | |
118 | */ | |
119 | struct p9_rdma_req; | |
120 | struct p9_rdma_context { | |
121 | enum ib_wc_opcode wc_op; | |
122 | dma_addr_t busa; | |
123 | union { | |
124 | struct p9_req_t *req; | |
125 | struct p9_fcall *rc; | |
126 | }; | |
127 | }; | |
128 | ||
129 | /** | |
130 | * p9_rdma_opts - Collection of mount options | |
131 | * @port: port of connection | |
132 | * @sq_depth: The requested depth of the SQ. This really doesn't need | |
133 | * to be any deeper than the number of threads used in the client | |
134 | * @rq_depth: The depth of the RQ. Should be greater than or equal to SQ depth | |
135 | * @timeout: Time to wait in msecs for CM events | |
136 | */ | |
137 | struct p9_rdma_opts { | |
138 | short port; | |
139 | int sq_depth; | |
140 | int rq_depth; | |
141 | long timeout; | |
142 | }; | |
143 | ||
144 | /* | |
145 | * Option Parsing (code inspired by NFS code) | |
146 | */ | |
147 | enum { | |
148 | /* Options that take integer arguments */ | |
149 | Opt_port, Opt_rq_depth, Opt_sq_depth, Opt_timeout, Opt_err, | |
150 | }; | |
151 | ||
152 | static match_table_t tokens = { | |
153 | {Opt_port, "port=%u"}, | |
154 | {Opt_sq_depth, "sq=%u"}, | |
155 | {Opt_rq_depth, "rq=%u"}, | |
156 | {Opt_timeout, "timeout=%u"}, | |
157 | {Opt_err, NULL}, | |
158 | }; | |
159 | ||
160 | /** | |
0e15597e AK |
161 | * parse_opts - parse mount options into rdma options structure |
162 | * @params: options string passed from mount | |
163 | * @opts: rdma transport-specific structure to parse options into | |
fc79d4b1 TT |
164 | * |
165 | * Returns 0 upon success, -ERRNO upon failure | |
166 | */ | |
167 | static int parse_opts(char *params, struct p9_rdma_opts *opts) | |
168 | { | |
169 | char *p; | |
170 | substring_t args[MAX_OPT_ARGS]; | |
171 | int option; | |
d8c8a9e3 | 172 | char *options, *tmp_options; |
fc79d4b1 TT |
173 | |
174 | opts->port = P9_PORT; | |
175 | opts->sq_depth = P9_RDMA_SQ_DEPTH; | |
176 | opts->rq_depth = P9_RDMA_RQ_DEPTH; | |
177 | opts->timeout = P9_RDMA_TIMEOUT; | |
178 | ||
179 | if (!params) | |
180 | return 0; | |
181 | ||
d8c8a9e3 EVH |
182 | tmp_options = kstrdup(params, GFP_KERNEL); |
183 | if (!tmp_options) { | |
5d385153 JP |
184 | p9_debug(P9_DEBUG_ERROR, |
185 | "failed to allocate copy of option string\n"); | |
fc79d4b1 TT |
186 | return -ENOMEM; |
187 | } | |
d8c8a9e3 | 188 | options = tmp_options; |
fc79d4b1 TT |
189 | |
190 | while ((p = strsep(&options, ",")) != NULL) { | |
191 | int token; | |
192 | int r; | |
193 | if (!*p) | |
194 | continue; | |
195 | token = match_token(p, tokens, args); | |
8a5daf1e SD |
196 | if (token == Opt_err) |
197 | continue; | |
fc79d4b1 TT |
198 | r = match_int(&args[0], &option); |
199 | if (r < 0) { | |
5d385153 JP |
200 | p9_debug(P9_DEBUG_ERROR, |
201 | "integer field, but no integer?\n"); | |
fc79d4b1 TT |
202 | continue; |
203 | } | |
204 | switch (token) { | |
205 | case Opt_port: | |
206 | opts->port = option; | |
207 | break; | |
208 | case Opt_sq_depth: | |
209 | opts->sq_depth = option; | |
210 | break; | |
211 | case Opt_rq_depth: | |
212 | opts->rq_depth = option; | |
213 | break; | |
214 | case Opt_timeout: | |
215 | opts->timeout = option; | |
216 | break; | |
217 | default: | |
218 | continue; | |
219 | } | |
220 | } | |
221 | /* RQ must be at least as large as the SQ */ | |
222 | opts->rq_depth = max(opts->rq_depth, opts->sq_depth); | |
d8c8a9e3 | 223 | kfree(tmp_options); |
fc79d4b1 TT |
224 | return 0; |
225 | } | |
226 | ||
227 | static int | |
228 | p9_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event) | |
229 | { | |
230 | struct p9_client *c = id->context; | |
231 | struct p9_trans_rdma *rdma = c->trans; | |
232 | switch (event->event) { | |
233 | case RDMA_CM_EVENT_ADDR_RESOLVED: | |
234 | BUG_ON(rdma->state != P9_RDMA_INIT); | |
235 | rdma->state = P9_RDMA_ADDR_RESOLVED; | |
236 | break; | |
237 | ||
238 | case RDMA_CM_EVENT_ROUTE_RESOLVED: | |
239 | BUG_ON(rdma->state != P9_RDMA_ADDR_RESOLVED); | |
240 | rdma->state = P9_RDMA_ROUTE_RESOLVED; | |
241 | break; | |
242 | ||
243 | case RDMA_CM_EVENT_ESTABLISHED: | |
244 | BUG_ON(rdma->state != P9_RDMA_ROUTE_RESOLVED); | |
245 | rdma->state = P9_RDMA_CONNECTED; | |
246 | break; | |
247 | ||
248 | case RDMA_CM_EVENT_DISCONNECTED: | |
249 | if (rdma) | |
250 | rdma->state = P9_RDMA_CLOSED; | |
251 | if (c) | |
252 | c->status = Disconnected; | |
253 | break; | |
254 | ||
255 | case RDMA_CM_EVENT_TIMEWAIT_EXIT: | |
256 | break; | |
257 | ||
258 | case RDMA_CM_EVENT_ADDR_CHANGE: | |
259 | case RDMA_CM_EVENT_ROUTE_ERROR: | |
260 | case RDMA_CM_EVENT_DEVICE_REMOVAL: | |
261 | case RDMA_CM_EVENT_MULTICAST_JOIN: | |
262 | case RDMA_CM_EVENT_MULTICAST_ERROR: | |
263 | case RDMA_CM_EVENT_REJECTED: | |
264 | case RDMA_CM_EVENT_CONNECT_REQUEST: | |
265 | case RDMA_CM_EVENT_CONNECT_RESPONSE: | |
266 | case RDMA_CM_EVENT_CONNECT_ERROR: | |
267 | case RDMA_CM_EVENT_ADDR_ERROR: | |
268 | case RDMA_CM_EVENT_UNREACHABLE: | |
269 | c->status = Disconnected; | |
270 | rdma_disconnect(rdma->cm_id); | |
271 | break; | |
272 | default: | |
273 | BUG(); | |
274 | } | |
275 | complete(&rdma->cm_done); | |
276 | return 0; | |
277 | } | |
278 | ||
279 | static void | |
280 | handle_recv(struct p9_client *client, struct p9_trans_rdma *rdma, | |
281 | struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len) | |
282 | { | |
283 | struct p9_req_t *req; | |
284 | int err = 0; | |
285 | int16_t tag; | |
286 | ||
287 | req = NULL; | |
288 | ib_dma_unmap_single(rdma->cm_id->device, c->busa, client->msize, | |
289 | DMA_FROM_DEVICE); | |
290 | ||
291 | if (status != IB_WC_SUCCESS) | |
292 | goto err_out; | |
293 | ||
294 | err = p9_parse_header(c->rc, NULL, NULL, &tag, 1); | |
295 | if (err) | |
296 | goto err_out; | |
297 | ||
298 | req = p9_tag_lookup(client, tag); | |
299 | if (!req) | |
300 | goto err_out; | |
301 | ||
47229ff8 SD |
302 | /* Check that we have not yet received a reply for this request. |
303 | */ | |
304 | if (unlikely(req->rc)) { | |
305 | pr_err("Duplicate reply for request %d", tag); | |
306 | goto err_out; | |
307 | } | |
308 | ||
fc79d4b1 | 309 | req->rc = c->rc; |
2b6e72ed | 310 | p9_client_cb(client, req, REQ_STATUS_RCVD); |
fc79d4b1 TT |
311 | |
312 | return; | |
313 | ||
314 | err_out: | |
5d385153 | 315 | p9_debug(P9_DEBUG_ERROR, "req %p err %d status %d\n", req, err, status); |
fc79d4b1 TT |
316 | rdma->state = P9_RDMA_FLUSHING; |
317 | client->status = Disconnected; | |
fc79d4b1 TT |
318 | } |
319 | ||
320 | static void | |
321 | handle_send(struct p9_client *client, struct p9_trans_rdma *rdma, | |
322 | struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len) | |
323 | { | |
324 | ib_dma_unmap_single(rdma->cm_id->device, | |
325 | c->busa, c->req->tc->size, | |
326 | DMA_TO_DEVICE); | |
327 | } | |
328 | ||
329 | static void qp_event_handler(struct ib_event *event, void *context) | |
330 | { | |
5d385153 JP |
331 | p9_debug(P9_DEBUG_ERROR, "QP event %d context %p\n", |
332 | event->event, context); | |
fc79d4b1 TT |
333 | } |
334 | ||
335 | static void cq_comp_handler(struct ib_cq *cq, void *cq_context) | |
336 | { | |
337 | struct p9_client *client = cq_context; | |
338 | struct p9_trans_rdma *rdma = client->trans; | |
339 | int ret; | |
340 | struct ib_wc wc; | |
341 | ||
342 | ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP); | |
343 | while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) { | |
344 | struct p9_rdma_context *c = (void *) (unsigned long) wc.wr_id; | |
345 | ||
346 | switch (c->wc_op) { | |
347 | case IB_WC_RECV: | |
fc79d4b1 | 348 | handle_recv(client, rdma, c, wc.status, wc.byte_len); |
fd453d0e | 349 | up(&rdma->rq_sem); |
fc79d4b1 TT |
350 | break; |
351 | ||
352 | case IB_WC_SEND: | |
353 | handle_send(client, rdma, c, wc.status, wc.byte_len); | |
354 | up(&rdma->sq_sem); | |
355 | break; | |
356 | ||
357 | default: | |
5d385153 | 358 | pr_err("unexpected completion type, c->wc_op=%d, wc.opcode=%d, status=%d\n", |
fc79d4b1 TT |
359 | c->wc_op, wc.opcode, wc.status); |
360 | break; | |
361 | } | |
362 | kfree(c); | |
363 | } | |
364 | } | |
365 | ||
366 | static void cq_event_handler(struct ib_event *e, void *v) | |
367 | { | |
5d385153 | 368 | p9_debug(P9_DEBUG_ERROR, "CQ event %d context %p\n", e->event, v); |
fc79d4b1 TT |
369 | } |
370 | ||
371 | static void rdma_destroy_trans(struct p9_trans_rdma *rdma) | |
372 | { | |
373 | if (!rdma) | |
374 | return; | |
375 | ||
376 | if (rdma->dma_mr && !IS_ERR(rdma->dma_mr)) | |
377 | ib_dereg_mr(rdma->dma_mr); | |
378 | ||
379 | if (rdma->qp && !IS_ERR(rdma->qp)) | |
380 | ib_destroy_qp(rdma->qp); | |
381 | ||
382 | if (rdma->pd && !IS_ERR(rdma->pd)) | |
383 | ib_dealloc_pd(rdma->pd); | |
384 | ||
385 | if (rdma->cq && !IS_ERR(rdma->cq)) | |
386 | ib_destroy_cq(rdma->cq); | |
387 | ||
388 | if (rdma->cm_id && !IS_ERR(rdma->cm_id)) | |
389 | rdma_destroy_id(rdma->cm_id); | |
390 | ||
391 | kfree(rdma); | |
392 | } | |
393 | ||
394 | static int | |
395 | post_recv(struct p9_client *client, struct p9_rdma_context *c) | |
396 | { | |
397 | struct p9_trans_rdma *rdma = client->trans; | |
398 | struct ib_recv_wr wr, *bad_wr; | |
399 | struct ib_sge sge; | |
400 | ||
401 | c->busa = ib_dma_map_single(rdma->cm_id->device, | |
402 | c->rc->sdata, client->msize, | |
403 | DMA_FROM_DEVICE); | |
404 | if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) | |
405 | goto error; | |
406 | ||
407 | sge.addr = c->busa; | |
408 | sge.length = client->msize; | |
409 | sge.lkey = rdma->lkey; | |
410 | ||
411 | wr.next = NULL; | |
412 | c->wc_op = IB_WC_RECV; | |
413 | wr.wr_id = (unsigned long) c; | |
414 | wr.sg_list = &sge; | |
415 | wr.num_sge = 1; | |
416 | return ib_post_recv(rdma->qp, &wr, &bad_wr); | |
417 | ||
418 | error: | |
5d385153 | 419 | p9_debug(P9_DEBUG_ERROR, "EIO\n"); |
fc79d4b1 TT |
420 | return -EIO; |
421 | } | |
422 | ||
423 | static int rdma_request(struct p9_client *client, struct p9_req_t *req) | |
424 | { | |
425 | struct p9_trans_rdma *rdma = client->trans; | |
426 | struct ib_send_wr wr, *bad_wr; | |
427 | struct ib_sge sge; | |
428 | int err = 0; | |
429 | unsigned long flags; | |
430 | struct p9_rdma_context *c = NULL; | |
431 | struct p9_rdma_context *rpl_context = NULL; | |
432 | ||
1cff3306 SD |
433 | /* When an error occurs between posting the recv and the send, |
434 | * there will be a receive context posted without a pending request. | |
435 | * Since there is no way to "un-post" it, we remember it and skip | |
436 | * post_recv() for the next request. | |
437 | * So here, | |
438 | * see if we are this `next request' and need to absorb an excess rc. | |
439 | * If yes, then drop and free our own, and do not recv_post(). | |
440 | **/ | |
441 | if (unlikely(atomic_read(&rdma->excess_rc) > 0)) { | |
442 | if ((atomic_sub_return(1, &rdma->excess_rc) >= 0)) { | |
443 | /* Got one ! */ | |
444 | kfree(req->rc); | |
445 | req->rc = NULL; | |
446 | goto dont_need_post_recv; | |
447 | } else { | |
448 | /* We raced and lost. */ | |
449 | atomic_inc(&rdma->excess_rc); | |
450 | } | |
451 | } | |
452 | ||
fc79d4b1 | 453 | /* Allocate an fcall for the reply */ |
eeff66ef | 454 | rpl_context = kmalloc(sizeof *rpl_context, GFP_NOFS); |
1d6400c7 DB |
455 | if (!rpl_context) { |
456 | err = -ENOMEM; | |
2f52d07c | 457 | goto recv_error; |
1d6400c7 | 458 | } |
fc79d4b1 | 459 | rpl_context->rc = req->rc; |
fc79d4b1 TT |
460 | |
461 | /* | |
462 | * Post a receive buffer for this request. We need to ensure | |
463 | * there is a reply buffer available for every outstanding | |
464 | * request. A flushed request can result in no reply for an | |
465 | * outstanding request, so we must keep a count to avoid | |
466 | * overflowing the RQ. | |
467 | */ | |
2f52d07c SD |
468 | if (down_interruptible(&rdma->rq_sem)) { |
469 | err = -EINTR; | |
470 | goto recv_error; | |
471 | } | |
fd453d0e SD |
472 | |
473 | err = post_recv(client, rpl_context); | |
474 | if (err) { | |
475 | p9_debug(P9_DEBUG_FCALL, "POST RECV failed\n"); | |
2f52d07c | 476 | goto recv_error; |
fd453d0e | 477 | } |
fc79d4b1 TT |
478 | /* remove posted receive buffer from request structure */ |
479 | req->rc = NULL; | |
480 | ||
1cff3306 | 481 | dont_need_post_recv: |
fc79d4b1 | 482 | /* Post the request */ |
eeff66ef | 483 | c = kmalloc(sizeof *c, GFP_NOFS); |
1d6400c7 DB |
484 | if (!c) { |
485 | err = -ENOMEM; | |
2f52d07c | 486 | goto send_error; |
1d6400c7 | 487 | } |
fc79d4b1 TT |
488 | c->req = req; |
489 | ||
490 | c->busa = ib_dma_map_single(rdma->cm_id->device, | |
491 | c->req->tc->sdata, c->req->tc->size, | |
492 | DMA_TO_DEVICE); | |
2f52d07c SD |
493 | if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) { |
494 | err = -EIO; | |
495 | goto send_error; | |
496 | } | |
fc79d4b1 TT |
497 | |
498 | sge.addr = c->busa; | |
499 | sge.length = c->req->tc->size; | |
500 | sge.lkey = rdma->lkey; | |
501 | ||
502 | wr.next = NULL; | |
503 | c->wc_op = IB_WC_SEND; | |
504 | wr.wr_id = (unsigned long) c; | |
505 | wr.opcode = IB_WR_SEND; | |
506 | wr.send_flags = IB_SEND_SIGNALED; | |
507 | wr.sg_list = &sge; | |
508 | wr.num_sge = 1; | |
509 | ||
2f52d07c SD |
510 | if (down_interruptible(&rdma->sq_sem)) { |
511 | err = -EINTR; | |
512 | goto send_error; | |
513 | } | |
514 | ||
3f9d5b8d SD |
515 | /* Mark request as `sent' *before* we actually send it, |
516 | * because doing if after could erase the REQ_STATUS_RCVD | |
517 | * status in case of a very fast reply. | |
518 | */ | |
519 | req->status = REQ_STATUS_SENT; | |
2f52d07c SD |
520 | err = ib_post_send(rdma->qp, &wr, &bad_wr); |
521 | if (err) | |
522 | goto send_error; | |
fc79d4b1 | 523 | |
2f52d07c SD |
524 | /* Success */ |
525 | return 0; | |
fc79d4b1 | 526 | |
2f52d07c SD |
527 | /* Handle errors that happened during or while preparing the send: */ |
528 | send_error: | |
3f9d5b8d | 529 | req->status = REQ_STATUS_ERROR; |
1d6400c7 | 530 | kfree(c); |
2f52d07c | 531 | p9_debug(P9_DEBUG_ERROR, "Error %d in rdma_request()\n", err); |
1cff3306 SD |
532 | |
533 | /* Ach. | |
534 | * We did recv_post(), but not send. We have one recv_post in excess. | |
535 | */ | |
536 | atomic_inc(&rdma->excess_rc); | |
2f52d07c SD |
537 | return err; |
538 | ||
539 | /* Handle errors that happened during or while preparing post_recv(): */ | |
540 | recv_error: | |
1d6400c7 | 541 | kfree(rpl_context); |
fc79d4b1 TT |
542 | spin_lock_irqsave(&rdma->req_lock, flags); |
543 | if (rdma->state < P9_RDMA_CLOSING) { | |
544 | rdma->state = P9_RDMA_CLOSING; | |
545 | spin_unlock_irqrestore(&rdma->req_lock, flags); | |
546 | rdma_disconnect(rdma->cm_id); | |
547 | } else | |
548 | spin_unlock_irqrestore(&rdma->req_lock, flags); | |
549 | return err; | |
550 | } | |
551 | ||
552 | static void rdma_close(struct p9_client *client) | |
553 | { | |
554 | struct p9_trans_rdma *rdma; | |
555 | ||
556 | if (!client) | |
557 | return; | |
558 | ||
559 | rdma = client->trans; | |
560 | if (!rdma) | |
561 | return; | |
562 | ||
563 | client->status = Disconnected; | |
564 | rdma_disconnect(rdma->cm_id); | |
565 | rdma_destroy_trans(rdma); | |
566 | } | |
567 | ||
568 | /** | |
569 | * alloc_rdma - Allocate and initialize the rdma transport structure | |
fc79d4b1 TT |
570 | * @opts: Mount options structure |
571 | */ | |
572 | static struct p9_trans_rdma *alloc_rdma(struct p9_rdma_opts *opts) | |
573 | { | |
574 | struct p9_trans_rdma *rdma; | |
575 | ||
576 | rdma = kzalloc(sizeof(struct p9_trans_rdma), GFP_KERNEL); | |
577 | if (!rdma) | |
578 | return NULL; | |
579 | ||
580 | rdma->sq_depth = opts->sq_depth; | |
581 | rdma->rq_depth = opts->rq_depth; | |
582 | rdma->timeout = opts->timeout; | |
583 | spin_lock_init(&rdma->req_lock); | |
584 | init_completion(&rdma->cm_done); | |
585 | sema_init(&rdma->sq_sem, rdma->sq_depth); | |
fd453d0e | 586 | sema_init(&rdma->rq_sem, rdma->rq_depth); |
1cff3306 | 587 | atomic_set(&rdma->excess_rc, 0); |
fc79d4b1 TT |
588 | |
589 | return rdma; | |
590 | } | |
591 | ||
fc79d4b1 TT |
592 | static int rdma_cancel(struct p9_client *client, struct p9_req_t *req) |
593 | { | |
931700d2 SD |
594 | /* Nothing to do here. |
595 | * We will take care of it (if we have to) in rdma_cancelled() | |
596 | */ | |
fc79d4b1 TT |
597 | return 1; |
598 | } | |
599 | ||
931700d2 SD |
600 | /* A request has been fully flushed without a reply. |
601 | * That means we have posted one buffer in excess. | |
602 | */ | |
603 | static int rdma_cancelled(struct p9_client *client, struct p9_req_t *req) | |
604 | { | |
605 | struct p9_trans_rdma *rdma = client->trans; | |
606 | atomic_inc(&rdma->excess_rc); | |
607 | return 0; | |
608 | } | |
609 | ||
fc79d4b1 TT |
610 | /** |
611 | * trans_create_rdma - Transport method for creating atransport instance | |
612 | * @client: client instance | |
613 | * @addr: IP address string | |
614 | * @args: Mount options string | |
615 | */ | |
616 | static int | |
617 | rdma_create_trans(struct p9_client *client, const char *addr, char *args) | |
618 | { | |
619 | int err; | |
620 | struct p9_rdma_opts opts; | |
621 | struct p9_trans_rdma *rdma; | |
622 | struct rdma_conn_param conn_param; | |
623 | struct ib_qp_init_attr qp_attr; | |
624 | struct ib_device_attr devattr; | |
625 | ||
626 | /* Parse the transport specific mount options */ | |
627 | err = parse_opts(args, &opts); | |
628 | if (err < 0) | |
629 | return err; | |
630 | ||
631 | /* Create and initialize the RDMA transport structure */ | |
632 | rdma = alloc_rdma(&opts); | |
633 | if (!rdma) | |
634 | return -ENOMEM; | |
635 | ||
636 | /* Create the RDMA CM ID */ | |
b26f9b99 SH |
637 | rdma->cm_id = rdma_create_id(p9_cm_event_handler, client, RDMA_PS_TCP, |
638 | IB_QPT_RC); | |
fc79d4b1 TT |
639 | if (IS_ERR(rdma->cm_id)) |
640 | goto error; | |
641 | ||
517ac45a TT |
642 | /* Associate the client with the transport */ |
643 | client->trans = rdma; | |
644 | ||
fc79d4b1 TT |
645 | /* Resolve the server's address */ |
646 | rdma->addr.sin_family = AF_INET; | |
647 | rdma->addr.sin_addr.s_addr = in_aton(addr); | |
648 | rdma->addr.sin_port = htons(opts.port); | |
649 | err = rdma_resolve_addr(rdma->cm_id, NULL, | |
650 | (struct sockaddr *)&rdma->addr, | |
651 | rdma->timeout); | |
652 | if (err) | |
653 | goto error; | |
654 | err = wait_for_completion_interruptible(&rdma->cm_done); | |
655 | if (err || (rdma->state != P9_RDMA_ADDR_RESOLVED)) | |
656 | goto error; | |
657 | ||
658 | /* Resolve the route to the server */ | |
659 | err = rdma_resolve_route(rdma->cm_id, rdma->timeout); | |
660 | if (err) | |
661 | goto error; | |
662 | err = wait_for_completion_interruptible(&rdma->cm_done); | |
663 | if (err || (rdma->state != P9_RDMA_ROUTE_RESOLVED)) | |
664 | goto error; | |
665 | ||
666 | /* Query the device attributes */ | |
667 | err = ib_query_device(rdma->cm_id->device, &devattr); | |
668 | if (err) | |
669 | goto error; | |
670 | ||
671 | /* Create the Completion Queue */ | |
672 | rdma->cq = ib_create_cq(rdma->cm_id->device, cq_comp_handler, | |
673 | cq_event_handler, client, | |
674 | opts.sq_depth + opts.rq_depth + 1, 0); | |
675 | if (IS_ERR(rdma->cq)) | |
676 | goto error; | |
677 | ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP); | |
678 | ||
679 | /* Create the Protection Domain */ | |
680 | rdma->pd = ib_alloc_pd(rdma->cm_id->device); | |
681 | if (IS_ERR(rdma->pd)) | |
682 | goto error; | |
683 | ||
684 | /* Cache the DMA lkey in the transport */ | |
685 | rdma->dma_mr = NULL; | |
686 | if (devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY) | |
687 | rdma->lkey = rdma->cm_id->device->local_dma_lkey; | |
688 | else { | |
689 | rdma->dma_mr = ib_get_dma_mr(rdma->pd, IB_ACCESS_LOCAL_WRITE); | |
690 | if (IS_ERR(rdma->dma_mr)) | |
691 | goto error; | |
692 | rdma->lkey = rdma->dma_mr->lkey; | |
693 | } | |
694 | ||
695 | /* Create the Queue Pair */ | |
696 | memset(&qp_attr, 0, sizeof qp_attr); | |
697 | qp_attr.event_handler = qp_event_handler; | |
698 | qp_attr.qp_context = client; | |
699 | qp_attr.cap.max_send_wr = opts.sq_depth; | |
700 | qp_attr.cap.max_recv_wr = opts.rq_depth; | |
701 | qp_attr.cap.max_send_sge = P9_RDMA_SEND_SGE; | |
702 | qp_attr.cap.max_recv_sge = P9_RDMA_RECV_SGE; | |
703 | qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; | |
704 | qp_attr.qp_type = IB_QPT_RC; | |
705 | qp_attr.send_cq = rdma->cq; | |
706 | qp_attr.recv_cq = rdma->cq; | |
707 | err = rdma_create_qp(rdma->cm_id, rdma->pd, &qp_attr); | |
708 | if (err) | |
709 | goto error; | |
710 | rdma->qp = rdma->cm_id->qp; | |
711 | ||
712 | /* Request a connection */ | |
713 | memset(&conn_param, 0, sizeof(conn_param)); | |
714 | conn_param.private_data = NULL; | |
715 | conn_param.private_data_len = 0; | |
716 | conn_param.responder_resources = P9_RDMA_IRD; | |
717 | conn_param.initiator_depth = P9_RDMA_ORD; | |
718 | err = rdma_connect(rdma->cm_id, &conn_param); | |
719 | if (err) | |
720 | goto error; | |
721 | err = wait_for_completion_interruptible(&rdma->cm_done); | |
722 | if (err || (rdma->state != P9_RDMA_CONNECTED)) | |
723 | goto error; | |
724 | ||
fc79d4b1 TT |
725 | client->status = Connected; |
726 | ||
727 | return 0; | |
728 | ||
729 | error: | |
730 | rdma_destroy_trans(rdma); | |
731 | return -ENOTCONN; | |
732 | } | |
733 | ||
734 | static struct p9_trans_module p9_rdma_trans = { | |
735 | .name = "rdma", | |
736 | .maxsize = P9_RDMA_MAXSIZE, | |
737 | .def = 0, | |
738 | .owner = THIS_MODULE, | |
739 | .create = rdma_create_trans, | |
740 | .close = rdma_close, | |
741 | .request = rdma_request, | |
742 | .cancel = rdma_cancel, | |
931700d2 | 743 | .cancelled = rdma_cancelled, |
fc79d4b1 TT |
744 | }; |
745 | ||
746 | /** | |
747 | * p9_trans_rdma_init - Register the 9P RDMA transport driver | |
748 | */ | |
749 | static int __init p9_trans_rdma_init(void) | |
750 | { | |
751 | v9fs_register_trans(&p9_rdma_trans); | |
752 | return 0; | |
753 | } | |
754 | ||
755 | static void __exit p9_trans_rdma_exit(void) | |
756 | { | |
757 | v9fs_unregister_trans(&p9_rdma_trans); | |
758 | } | |
759 | ||
760 | module_init(p9_trans_rdma_init); | |
761 | module_exit(p9_trans_rdma_exit); | |
762 | ||
763 | MODULE_AUTHOR("Tom Tucker <tom@opengridcomputing.com>"); | |
764 | MODULE_DESCRIPTION("RDMA Transport for 9P"); | |
765 | MODULE_LICENSE("Dual BSD/GPL"); |