blob: ae90758d8e9b2f548bb7c5716e6c3b3d5598b96a [file] [log] [blame]
Tom Tucker377f9b22007-12-12 16:13:21 -06001/*
2 * Copyright (c) 2005-2007 Network Appliance, Inc. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the BSD-type
8 * license below:
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 *
14 * Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 *
17 * Redistributions in binary form must reproduce the above
18 * copyright notice, this list of conditions and the following
19 * disclaimer in the documentation and/or other materials provided
20 * with the distribution.
21 *
22 * Neither the name of the Network Appliance, Inc. nor the names of
23 * its contributors may be used to endorse or promote products
24 * derived from this software without specific prior written
25 * permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 *
39 * Author: Tom Tucker <tom@opengridcomputing.com>
40 */
41
42#include <linux/sunrpc/svc_xprt.h>
43#include <linux/sunrpc/debug.h>
44#include <linux/sunrpc/rpc_rdma.h>
45#include <linux/spinlock.h>
46#include <rdma/ib_verbs.h>
47#include <rdma/rdma_cm.h>
48#include <linux/sunrpc/svc_rdma.h>
49
50#define RPCDBG_FACILITY RPCDBG_SVCXPRT
51
52static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
53 struct sockaddr *sa, int salen,
54 int flags);
55static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt);
56static void svc_rdma_release_rqst(struct svc_rqst *);
Tom Tucker377f9b22007-12-12 16:13:21 -060057static void dto_tasklet_func(unsigned long data);
58static void svc_rdma_detach(struct svc_xprt *xprt);
59static void svc_rdma_free(struct svc_xprt *xprt);
60static int svc_rdma_has_wspace(struct svc_xprt *xprt);
61static void rq_cq_reap(struct svcxprt_rdma *xprt);
62static void sq_cq_reap(struct svcxprt_rdma *xprt);
63
64DECLARE_TASKLET(dto_tasklet, dto_tasklet_func, 0UL);
65static DEFINE_SPINLOCK(dto_lock);
66static LIST_HEAD(dto_xprt_q);
67
68static struct svc_xprt_ops svc_rdma_ops = {
69 .xpo_create = svc_rdma_create,
70 .xpo_recvfrom = svc_rdma_recvfrom,
71 .xpo_sendto = svc_rdma_sendto,
72 .xpo_release_rqst = svc_rdma_release_rqst,
73 .xpo_detach = svc_rdma_detach,
74 .xpo_free = svc_rdma_free,
75 .xpo_prep_reply_hdr = svc_rdma_prep_reply_hdr,
76 .xpo_has_wspace = svc_rdma_has_wspace,
77 .xpo_accept = svc_rdma_accept,
78};
79
80struct svc_xprt_class svc_rdma_class = {
81 .xcl_name = "rdma",
82 .xcl_owner = THIS_MODULE,
83 .xcl_ops = &svc_rdma_ops,
84 .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
85};
86
87static int rdma_bump_context_cache(struct svcxprt_rdma *xprt)
88{
89 int target;
90 int at_least_one = 0;
91 struct svc_rdma_op_ctxt *ctxt;
92
93 target = min(xprt->sc_ctxt_cnt + xprt->sc_ctxt_bump,
94 xprt->sc_ctxt_max);
95
96 spin_lock_bh(&xprt->sc_ctxt_lock);
97 while (xprt->sc_ctxt_cnt < target) {
98 xprt->sc_ctxt_cnt++;
99 spin_unlock_bh(&xprt->sc_ctxt_lock);
100
101 ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL);
102
103 spin_lock_bh(&xprt->sc_ctxt_lock);
104 if (ctxt) {
105 at_least_one = 1;
Tom Tucker87407672008-04-30 20:44:39 -0500106 INIT_LIST_HEAD(&ctxt->free_list);
107 list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
Tom Tucker377f9b22007-12-12 16:13:21 -0600108 } else {
109 /* kmalloc failed...give up for now */
110 xprt->sc_ctxt_cnt--;
111 break;
112 }
113 }
114 spin_unlock_bh(&xprt->sc_ctxt_lock);
115 dprintk("svcrdma: sc_ctxt_max=%d, sc_ctxt_cnt=%d\n",
116 xprt->sc_ctxt_max, xprt->sc_ctxt_cnt);
117 return at_least_one;
118}
119
120struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt)
121{
122 struct svc_rdma_op_ctxt *ctxt;
123
124 while (1) {
125 spin_lock_bh(&xprt->sc_ctxt_lock);
Tom Tucker87407672008-04-30 20:44:39 -0500126 if (unlikely(list_empty(&xprt->sc_ctxt_free))) {
Tom Tucker377f9b22007-12-12 16:13:21 -0600127 /* Try to bump my cache. */
128 spin_unlock_bh(&xprt->sc_ctxt_lock);
129
130 if (rdma_bump_context_cache(xprt))
131 continue;
132
133 printk(KERN_INFO "svcrdma: sleeping waiting for "
134 "context memory on xprt=%p\n",
135 xprt);
136 schedule_timeout_uninterruptible(msecs_to_jiffies(500));
137 continue;
138 }
Tom Tucker87407672008-04-30 20:44:39 -0500139 ctxt = list_entry(xprt->sc_ctxt_free.next,
140 struct svc_rdma_op_ctxt,
141 free_list);
142 list_del_init(&ctxt->free_list);
Tom Tucker377f9b22007-12-12 16:13:21 -0600143 spin_unlock_bh(&xprt->sc_ctxt_lock);
144 ctxt->xprt = xprt;
145 INIT_LIST_HEAD(&ctxt->dto_q);
146 ctxt->count = 0;
Tom Tucker87407672008-04-30 20:44:39 -0500147 atomic_inc(&xprt->sc_ctxt_used);
Tom Tucker377f9b22007-12-12 16:13:21 -0600148 break;
149 }
150 return ctxt;
151}
152
153void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages)
154{
155 struct svcxprt_rdma *xprt;
156 int i;
157
158 BUG_ON(!ctxt);
159 xprt = ctxt->xprt;
160 if (free_pages)
161 for (i = 0; i < ctxt->count; i++)
162 put_page(ctxt->pages[i]);
163
164 for (i = 0; i < ctxt->count; i++)
Tom Tucker97a3df32008-05-01 14:02:45 -0500165 ib_dma_unmap_single(xprt->sc_cm_id->device,
166 ctxt->sge[i].addr,
167 ctxt->sge[i].length,
168 ctxt->direction);
Tom Tucker87407672008-04-30 20:44:39 -0500169
Tom Tucker377f9b22007-12-12 16:13:21 -0600170 spin_lock_bh(&xprt->sc_ctxt_lock);
Tom Tucker87407672008-04-30 20:44:39 -0500171 list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
Tom Tucker377f9b22007-12-12 16:13:21 -0600172 spin_unlock_bh(&xprt->sc_ctxt_lock);
Tom Tucker87407672008-04-30 20:44:39 -0500173 atomic_dec(&xprt->sc_ctxt_used);
Tom Tucker377f9b22007-12-12 16:13:21 -0600174}
175
Tom Tuckerab96ddd2008-05-28 13:54:04 -0500176/* Temporary NFS request map cache. Created in svc_rdma.c */
177extern struct kmem_cache *svc_rdma_map_cachep;
178
179/*
180 * Temporary NFS req mappings are shared across all transport
181 * instances. These are short lived and should be bounded by the number
182 * of concurrent server threads * depth of the SQ.
183 */
184struct svc_rdma_req_map *svc_rdma_get_req_map(void)
185{
186 struct svc_rdma_req_map *map;
187 while (1) {
188 map = kmem_cache_alloc(svc_rdma_map_cachep, GFP_KERNEL);
189 if (map)
190 break;
191 schedule_timeout_uninterruptible(msecs_to_jiffies(500));
192 }
193 map->count = 0;
194 return map;
195}
196
197void svc_rdma_put_req_map(struct svc_rdma_req_map *map)
198{
199 kmem_cache_free(svc_rdma_map_cachep, map);
200}
201
Tom Tucker377f9b22007-12-12 16:13:21 -0600202/* ib_cq event handler */
203static void cq_event_handler(struct ib_event *event, void *context)
204{
205 struct svc_xprt *xprt = context;
206 dprintk("svcrdma: received CQ event id=%d, context=%p\n",
207 event->event, context);
208 set_bit(XPT_CLOSE, &xprt->xpt_flags);
209}
210
211/* QP event handler */
212static void qp_event_handler(struct ib_event *event, void *context)
213{
214 struct svc_xprt *xprt = context;
215
216 switch (event->event) {
217 /* These are considered benign events */
218 case IB_EVENT_PATH_MIG:
219 case IB_EVENT_COMM_EST:
220 case IB_EVENT_SQ_DRAINED:
221 case IB_EVENT_QP_LAST_WQE_REACHED:
222 dprintk("svcrdma: QP event %d received for QP=%p\n",
223 event->event, event->element.qp);
224 break;
225 /* These are considered fatal events */
226 case IB_EVENT_PATH_MIG_ERR:
227 case IB_EVENT_QP_FATAL:
228 case IB_EVENT_QP_REQ_ERR:
229 case IB_EVENT_QP_ACCESS_ERR:
230 case IB_EVENT_DEVICE_FATAL:
231 default:
232 dprintk("svcrdma: QP ERROR event %d received for QP=%p, "
233 "closing transport\n",
234 event->event, event->element.qp);
235 set_bit(XPT_CLOSE, &xprt->xpt_flags);
236 break;
237 }
238}
239
240/*
241 * Data Transfer Operation Tasklet
242 *
243 * Walks a list of transports with I/O pending, removing entries as
244 * they are added to the server's I/O pending list. Two bits indicate
245 * if SQ, RQ, or both have I/O pending. The dto_lock is an irqsave
246 * spinlock that serializes access to the transport list with the RQ
247 * and SQ interrupt handlers.
248 */
249static void dto_tasklet_func(unsigned long data)
250{
251 struct svcxprt_rdma *xprt;
252 unsigned long flags;
253
254 spin_lock_irqsave(&dto_lock, flags);
255 while (!list_empty(&dto_xprt_q)) {
256 xprt = list_entry(dto_xprt_q.next,
257 struct svcxprt_rdma, sc_dto_q);
258 list_del_init(&xprt->sc_dto_q);
259 spin_unlock_irqrestore(&dto_lock, flags);
260
Tom Tuckerdbcd00e2008-05-06 11:33:11 -0500261 rq_cq_reap(xprt);
262 sq_cq_reap(xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600263
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400264 svc_xprt_put(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600265 spin_lock_irqsave(&dto_lock, flags);
266 }
267 spin_unlock_irqrestore(&dto_lock, flags);
268}
269
270/*
271 * Receive Queue Completion Handler
272 *
273 * Since an RQ completion handler is called on interrupt context, we
274 * need to defer the handling of the I/O to a tasklet
275 */
276static void rq_comp_handler(struct ib_cq *cq, void *cq_context)
277{
278 struct svcxprt_rdma *xprt = cq_context;
279 unsigned long flags;
280
Tom Tucker17113862008-05-01 11:13:50 -0500281 /* Guard against unconditional flush call for destroyed QP */
282 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0)
283 return;
284
Tom Tucker377f9b22007-12-12 16:13:21 -0600285 /*
286 * Set the bit regardless of whether or not it's on the list
287 * because it may be on the list already due to an SQ
288 * completion.
Tom Tucker17113862008-05-01 11:13:50 -0500289 */
Tom Tucker377f9b22007-12-12 16:13:21 -0600290 set_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags);
291
292 /*
293 * If this transport is not already on the DTO transport queue,
294 * add it
295 */
296 spin_lock_irqsave(&dto_lock, flags);
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400297 if (list_empty(&xprt->sc_dto_q)) {
298 svc_xprt_get(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600299 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400300 }
Tom Tucker377f9b22007-12-12 16:13:21 -0600301 spin_unlock_irqrestore(&dto_lock, flags);
302
303 /* Tasklet does all the work to avoid irqsave locks. */
304 tasklet_schedule(&dto_tasklet);
305}
306
307/*
308 * rq_cq_reap - Process the RQ CQ.
309 *
310 * Take all completing WC off the CQE and enqueue the associated DTO
311 * context on the dto_q for the transport.
Tom Tucker0905c0f2008-05-01 10:49:03 -0500312 *
313 * Note that caller must hold a transport reference.
Tom Tucker377f9b22007-12-12 16:13:21 -0600314 */
315static void rq_cq_reap(struct svcxprt_rdma *xprt)
316{
317 int ret;
318 struct ib_wc wc;
319 struct svc_rdma_op_ctxt *ctxt = NULL;
320
Tom Tuckerdbcd00e2008-05-06 11:33:11 -0500321 if (!test_and_clear_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags))
322 return;
323
324 ib_req_notify_cq(xprt->sc_rq_cq, IB_CQ_NEXT_COMP);
Tom Tucker377f9b22007-12-12 16:13:21 -0600325 atomic_inc(&rdma_stat_rq_poll);
326
Tom Tucker377f9b22007-12-12 16:13:21 -0600327 while ((ret = ib_poll_cq(xprt->sc_rq_cq, 1, &wc)) > 0) {
328 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id;
329 ctxt->wc_status = wc.status;
330 ctxt->byte_len = wc.byte_len;
331 if (wc.status != IB_WC_SUCCESS) {
332 /* Close the transport */
Tom Tucker0905c0f2008-05-01 10:49:03 -0500333 dprintk("svcrdma: transport closing putting ctxt %p\n", ctxt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600334 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
335 svc_rdma_put_context(ctxt, 1);
Tom Tucker0905c0f2008-05-01 10:49:03 -0500336 svc_xprt_put(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600337 continue;
338 }
Tom Tucker47698e02008-05-06 11:49:05 -0500339 spin_lock_bh(&xprt->sc_rq_dto_lock);
Tom Tucker377f9b22007-12-12 16:13:21 -0600340 list_add_tail(&ctxt->dto_q, &xprt->sc_rq_dto_q);
Tom Tucker47698e02008-05-06 11:49:05 -0500341 spin_unlock_bh(&xprt->sc_rq_dto_lock);
Tom Tucker0905c0f2008-05-01 10:49:03 -0500342 svc_xprt_put(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600343 }
Tom Tucker377f9b22007-12-12 16:13:21 -0600344
345 if (ctxt)
346 atomic_inc(&rdma_stat_rq_prod);
Tom Tuckerdbcd00e2008-05-06 11:33:11 -0500347
348 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
349 /*
350 * If data arrived before established event,
351 * don't enqueue. This defers RPC I/O until the
352 * RDMA connection is complete.
353 */
354 if (!test_bit(RDMAXPRT_CONN_PENDING, &xprt->sc_flags))
355 svc_xprt_enqueue(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600356}
357
358/*
359 * Send Queue Completion Handler - potentially called on interrupt context.
Tom Tucker0905c0f2008-05-01 10:49:03 -0500360 *
361 * Note that caller must hold a transport reference.
Tom Tucker377f9b22007-12-12 16:13:21 -0600362 */
363static void sq_cq_reap(struct svcxprt_rdma *xprt)
364{
365 struct svc_rdma_op_ctxt *ctxt = NULL;
366 struct ib_wc wc;
367 struct ib_cq *cq = xprt->sc_sq_cq;
368 int ret;
369
Tom Tuckerdbcd00e2008-05-06 11:33:11 -0500370
371 if (!test_and_clear_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags))
372 return;
373
374 ib_req_notify_cq(xprt->sc_sq_cq, IB_CQ_NEXT_COMP);
Tom Tucker377f9b22007-12-12 16:13:21 -0600375 atomic_inc(&rdma_stat_sq_poll);
376 while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) {
377 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id;
378 xprt = ctxt->xprt;
379
380 if (wc.status != IB_WC_SUCCESS)
381 /* Close the transport */
382 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
383
384 /* Decrement used SQ WR count */
385 atomic_dec(&xprt->sc_sq_count);
386 wake_up(&xprt->sc_send_wait);
387
388 switch (ctxt->wr_op) {
389 case IB_WR_SEND:
390 case IB_WR_RDMA_WRITE:
391 svc_rdma_put_context(ctxt, 1);
392 break;
393
394 case IB_WR_RDMA_READ:
395 if (test_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags)) {
Tom Tucker02e74522008-04-30 19:50:56 -0500396 struct svc_rdma_op_ctxt *read_hdr = ctxt->read_hdr;
397 BUG_ON(!read_hdr);
Tom Tucker377f9b22007-12-12 16:13:21 -0600398 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
Tom Tucker377f9b22007-12-12 16:13:21 -0600399 spin_lock_bh(&xprt->sc_read_complete_lock);
Tom Tucker02e74522008-04-30 19:50:56 -0500400 list_add_tail(&read_hdr->dto_q,
Tom Tucker377f9b22007-12-12 16:13:21 -0600401 &xprt->sc_read_complete_q);
402 spin_unlock_bh(&xprt->sc_read_complete_lock);
403 svc_xprt_enqueue(&xprt->sc_xprt);
404 }
Tom Tucker02e74522008-04-30 19:50:56 -0500405 svc_rdma_put_context(ctxt, 0);
Tom Tucker377f9b22007-12-12 16:13:21 -0600406 break;
407
408 default:
409 printk(KERN_ERR "svcrdma: unexpected completion type, "
410 "opcode=%d, status=%d\n",
411 wc.opcode, wc.status);
412 break;
413 }
Tom Tucker0905c0f2008-05-01 10:49:03 -0500414 svc_xprt_put(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600415 }
416
417 if (ctxt)
418 atomic_inc(&rdma_stat_sq_prod);
419}
420
421static void sq_comp_handler(struct ib_cq *cq, void *cq_context)
422{
423 struct svcxprt_rdma *xprt = cq_context;
424 unsigned long flags;
425
Tom Tucker17113862008-05-01 11:13:50 -0500426 /* Guard against unconditional flush call for destroyed QP */
427 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0)
428 return;
429
Tom Tucker377f9b22007-12-12 16:13:21 -0600430 /*
431 * Set the bit regardless of whether or not it's on the list
432 * because it may be on the list already due to an RQ
433 * completion.
Tom Tucker17113862008-05-01 11:13:50 -0500434 */
Tom Tucker377f9b22007-12-12 16:13:21 -0600435 set_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags);
436
437 /*
438 * If this transport is not already on the DTO transport queue,
439 * add it
440 */
441 spin_lock_irqsave(&dto_lock, flags);
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400442 if (list_empty(&xprt->sc_dto_q)) {
443 svc_xprt_get(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600444 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400445 }
Tom Tucker377f9b22007-12-12 16:13:21 -0600446 spin_unlock_irqrestore(&dto_lock, flags);
447
448 /* Tasklet does all the work to avoid irqsave locks. */
449 tasklet_schedule(&dto_tasklet);
450}
451
452static void create_context_cache(struct svcxprt_rdma *xprt,
453 int ctxt_count, int ctxt_bump, int ctxt_max)
454{
455 struct svc_rdma_op_ctxt *ctxt;
456 int i;
457
458 xprt->sc_ctxt_max = ctxt_max;
459 xprt->sc_ctxt_bump = ctxt_bump;
460 xprt->sc_ctxt_cnt = 0;
Tom Tucker87407672008-04-30 20:44:39 -0500461 atomic_set(&xprt->sc_ctxt_used, 0);
462
463 INIT_LIST_HEAD(&xprt->sc_ctxt_free);
Tom Tucker377f9b22007-12-12 16:13:21 -0600464 for (i = 0; i < ctxt_count; i++) {
465 ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL);
466 if (ctxt) {
Tom Tucker87407672008-04-30 20:44:39 -0500467 INIT_LIST_HEAD(&ctxt->free_list);
468 list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
Tom Tucker377f9b22007-12-12 16:13:21 -0600469 xprt->sc_ctxt_cnt++;
470 }
471 }
472}
473
Tom Tucker87407672008-04-30 20:44:39 -0500474static void destroy_context_cache(struct svcxprt_rdma *xprt)
Tom Tucker377f9b22007-12-12 16:13:21 -0600475{
Tom Tucker87407672008-04-30 20:44:39 -0500476 while (!list_empty(&xprt->sc_ctxt_free)) {
477 struct svc_rdma_op_ctxt *ctxt;
478 ctxt = list_entry(xprt->sc_ctxt_free.next,
479 struct svc_rdma_op_ctxt,
480 free_list);
481 list_del_init(&ctxt->free_list);
Tom Tucker377f9b22007-12-12 16:13:21 -0600482 kfree(ctxt);
Tom Tucker87407672008-04-30 20:44:39 -0500483 }
Tom Tucker377f9b22007-12-12 16:13:21 -0600484}
485
486static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
487 int listener)
488{
489 struct svcxprt_rdma *cma_xprt = kzalloc(sizeof *cma_xprt, GFP_KERNEL);
490
491 if (!cma_xprt)
492 return NULL;
493 svc_xprt_init(&svc_rdma_class, &cma_xprt->sc_xprt, serv);
494 INIT_LIST_HEAD(&cma_xprt->sc_accept_q);
495 INIT_LIST_HEAD(&cma_xprt->sc_dto_q);
496 INIT_LIST_HEAD(&cma_xprt->sc_rq_dto_q);
497 INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q);
498 init_waitqueue_head(&cma_xprt->sc_send_wait);
499
500 spin_lock_init(&cma_xprt->sc_lock);
501 spin_lock_init(&cma_xprt->sc_read_complete_lock);
502 spin_lock_init(&cma_xprt->sc_ctxt_lock);
503 spin_lock_init(&cma_xprt->sc_rq_dto_lock);
504
505 cma_xprt->sc_ord = svcrdma_ord;
506
507 cma_xprt->sc_max_req_size = svcrdma_max_req_size;
508 cma_xprt->sc_max_requests = svcrdma_max_requests;
509 cma_xprt->sc_sq_depth = svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT;
510 atomic_set(&cma_xprt->sc_sq_count, 0);
511
512 if (!listener) {
513 int reqs = cma_xprt->sc_max_requests;
514 create_context_cache(cma_xprt,
515 reqs << 1, /* starting size */
516 reqs, /* bump amount */
517 reqs +
518 cma_xprt->sc_sq_depth +
519 RPCRDMA_MAX_THREADS + 1); /* max */
Tom Tucker87407672008-04-30 20:44:39 -0500520 if (list_empty(&cma_xprt->sc_ctxt_free)) {
Tom Tucker377f9b22007-12-12 16:13:21 -0600521 kfree(cma_xprt);
522 return NULL;
523 }
524 clear_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
525 } else
526 set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
527
528 return cma_xprt;
529}
530
531struct page *svc_rdma_get_page(void)
532{
533 struct page *page;
534
535 while ((page = alloc_page(GFP_KERNEL)) == NULL) {
536 /* If we can't get memory, wait a bit and try again */
537 printk(KERN_INFO "svcrdma: out of memory...retrying in 1000 "
538 "jiffies.\n");
539 schedule_timeout_uninterruptible(msecs_to_jiffies(1000));
540 }
541 return page;
542}
543
544int svc_rdma_post_recv(struct svcxprt_rdma *xprt)
545{
546 struct ib_recv_wr recv_wr, *bad_recv_wr;
547 struct svc_rdma_op_ctxt *ctxt;
548 struct page *page;
549 unsigned long pa;
550 int sge_no;
551 int buflen;
552 int ret;
553
554 ctxt = svc_rdma_get_context(xprt);
555 buflen = 0;
556 ctxt->direction = DMA_FROM_DEVICE;
557 for (sge_no = 0; buflen < xprt->sc_max_req_size; sge_no++) {
558 BUG_ON(sge_no >= xprt->sc_max_sge);
559 page = svc_rdma_get_page();
560 ctxt->pages[sge_no] = page;
561 pa = ib_dma_map_page(xprt->sc_cm_id->device,
562 page, 0, PAGE_SIZE,
563 DMA_FROM_DEVICE);
564 ctxt->sge[sge_no].addr = pa;
565 ctxt->sge[sge_no].length = PAGE_SIZE;
566 ctxt->sge[sge_no].lkey = xprt->sc_phys_mr->lkey;
567 buflen += PAGE_SIZE;
568 }
569 ctxt->count = sge_no;
570 recv_wr.next = NULL;
571 recv_wr.sg_list = &ctxt->sge[0];
572 recv_wr.num_sge = ctxt->count;
573 recv_wr.wr_id = (u64)(unsigned long)ctxt;
574
Tom Tucker0905c0f2008-05-01 10:49:03 -0500575 svc_xprt_get(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600576 ret = ib_post_recv(xprt->sc_qp, &recv_wr, &bad_recv_wr);
Tom Tucker0905c0f2008-05-01 10:49:03 -0500577 if (ret) {
578 svc_xprt_put(&xprt->sc_xprt);
Tom Tucker05a08262008-04-25 14:11:31 -0500579 svc_rdma_put_context(ctxt, 1);
Tom Tucker0905c0f2008-05-01 10:49:03 -0500580 }
Tom Tucker377f9b22007-12-12 16:13:21 -0600581 return ret;
582}
583
584/*
585 * This function handles the CONNECT_REQUEST event on a listening
586 * endpoint. It is passed the cma_id for the _new_ connection. The context in
587 * this cma_id is inherited from the listening cma_id and is the svc_xprt
588 * structure for the listening endpoint.
589 *
590 * This function creates a new xprt for the new connection and enqueues it on
591 * the accept queue for the listent xprt. When the listen thread is kicked, it
592 * will call the recvfrom method on the listen xprt which will accept the new
593 * connection.
594 */
595static void handle_connect_req(struct rdma_cm_id *new_cma_id)
596{
597 struct svcxprt_rdma *listen_xprt = new_cma_id->context;
598 struct svcxprt_rdma *newxprt;
Tom Tuckeraf261af2008-05-07 13:52:42 -0500599 struct sockaddr *sa;
Tom Tucker377f9b22007-12-12 16:13:21 -0600600
601 /* Create a new transport */
602 newxprt = rdma_create_xprt(listen_xprt->sc_xprt.xpt_server, 0);
603 if (!newxprt) {
604 dprintk("svcrdma: failed to create new transport\n");
605 return;
606 }
607 newxprt->sc_cm_id = new_cma_id;
608 new_cma_id->context = newxprt;
609 dprintk("svcrdma: Creating newxprt=%p, cm_id=%p, listenxprt=%p\n",
610 newxprt, newxprt->sc_cm_id, listen_xprt);
611
Tom Tuckeraf261af2008-05-07 13:52:42 -0500612 /* Set the local and remote addresses in the transport */
613 sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr;
614 svc_xprt_set_remote(&newxprt->sc_xprt, sa, svc_addr_len(sa));
615 sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr;
616 svc_xprt_set_local(&newxprt->sc_xprt, sa, svc_addr_len(sa));
617
Tom Tucker377f9b22007-12-12 16:13:21 -0600618 /*
619 * Enqueue the new transport on the accept queue of the listening
620 * transport
621 */
622 spin_lock_bh(&listen_xprt->sc_lock);
623 list_add_tail(&newxprt->sc_accept_q, &listen_xprt->sc_accept_q);
624 spin_unlock_bh(&listen_xprt->sc_lock);
625
626 /*
627 * Can't use svc_xprt_received here because we are not on a
628 * rqstp thread
629 */
630 set_bit(XPT_CONN, &listen_xprt->sc_xprt.xpt_flags);
631 svc_xprt_enqueue(&listen_xprt->sc_xprt);
632}
633
634/*
635 * Handles events generated on the listening endpoint. These events will be
636 * either be incoming connect requests or adapter removal events.
637 */
638static int rdma_listen_handler(struct rdma_cm_id *cma_id,
639 struct rdma_cm_event *event)
640{
641 struct svcxprt_rdma *xprt = cma_id->context;
642 int ret = 0;
643
644 switch (event->event) {
645 case RDMA_CM_EVENT_CONNECT_REQUEST:
646 dprintk("svcrdma: Connect request on cma_id=%p, xprt = %p, "
647 "event=%d\n", cma_id, cma_id->context, event->event);
648 handle_connect_req(cma_id);
649 break;
650
651 case RDMA_CM_EVENT_ESTABLISHED:
652 /* Accept complete */
653 dprintk("svcrdma: Connection completed on LISTEN xprt=%p, "
654 "cm_id=%p\n", xprt, cma_id);
655 break;
656
657 case RDMA_CM_EVENT_DEVICE_REMOVAL:
658 dprintk("svcrdma: Device removal xprt=%p, cm_id=%p\n",
659 xprt, cma_id);
660 if (xprt)
661 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
662 break;
663
664 default:
665 dprintk("svcrdma: Unexpected event on listening endpoint %p, "
666 "event=%d\n", cma_id, event->event);
667 break;
668 }
669
670 return ret;
671}
672
673static int rdma_cma_handler(struct rdma_cm_id *cma_id,
674 struct rdma_cm_event *event)
675{
676 struct svc_xprt *xprt = cma_id->context;
677 struct svcxprt_rdma *rdma =
678 container_of(xprt, struct svcxprt_rdma, sc_xprt);
679 switch (event->event) {
680 case RDMA_CM_EVENT_ESTABLISHED:
681 /* Accept complete */
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400682 svc_xprt_get(xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600683 dprintk("svcrdma: Connection completed on DTO xprt=%p, "
684 "cm_id=%p\n", xprt, cma_id);
685 clear_bit(RDMAXPRT_CONN_PENDING, &rdma->sc_flags);
686 svc_xprt_enqueue(xprt);
687 break;
688 case RDMA_CM_EVENT_DISCONNECTED:
689 dprintk("svcrdma: Disconnect on DTO xprt=%p, cm_id=%p\n",
690 xprt, cma_id);
691 if (xprt) {
692 set_bit(XPT_CLOSE, &xprt->xpt_flags);
693 svc_xprt_enqueue(xprt);
Tom Tucker120693d2008-04-24 14:17:21 -0500694 svc_xprt_put(xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600695 }
696 break;
697 case RDMA_CM_EVENT_DEVICE_REMOVAL:
698 dprintk("svcrdma: Device removal cma_id=%p, xprt = %p, "
699 "event=%d\n", cma_id, xprt, event->event);
700 if (xprt) {
701 set_bit(XPT_CLOSE, &xprt->xpt_flags);
702 svc_xprt_enqueue(xprt);
703 }
704 break;
705 default:
706 dprintk("svcrdma: Unexpected event on DTO endpoint %p, "
707 "event=%d\n", cma_id, event->event);
708 break;
709 }
710 return 0;
711}
712
713/*
714 * Create a listening RDMA service endpoint.
715 */
716static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
717 struct sockaddr *sa, int salen,
718 int flags)
719{
720 struct rdma_cm_id *listen_id;
721 struct svcxprt_rdma *cma_xprt;
722 struct svc_xprt *xprt;
723 int ret;
724
725 dprintk("svcrdma: Creating RDMA socket\n");
726
727 cma_xprt = rdma_create_xprt(serv, 1);
728 if (!cma_xprt)
Tom Tucker58e8f622008-05-06 09:45:54 -0500729 return ERR_PTR(-ENOMEM);
Tom Tucker377f9b22007-12-12 16:13:21 -0600730 xprt = &cma_xprt->sc_xprt;
731
732 listen_id = rdma_create_id(rdma_listen_handler, cma_xprt, RDMA_PS_TCP);
733 if (IS_ERR(listen_id)) {
Tom Tucker58e8f622008-05-06 09:45:54 -0500734 ret = PTR_ERR(listen_id);
735 dprintk("svcrdma: rdma_create_id failed = %d\n", ret);
736 goto err0;
Tom Tucker377f9b22007-12-12 16:13:21 -0600737 }
Tom Tucker58e8f622008-05-06 09:45:54 -0500738
Tom Tucker377f9b22007-12-12 16:13:21 -0600739 ret = rdma_bind_addr(listen_id, sa);
740 if (ret) {
Tom Tucker377f9b22007-12-12 16:13:21 -0600741 dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret);
Tom Tucker58e8f622008-05-06 09:45:54 -0500742 goto err1;
Tom Tucker377f9b22007-12-12 16:13:21 -0600743 }
744 cma_xprt->sc_cm_id = listen_id;
745
746 ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG);
747 if (ret) {
Tom Tucker377f9b22007-12-12 16:13:21 -0600748 dprintk("svcrdma: rdma_listen failed = %d\n", ret);
Tom Tucker58e8f622008-05-06 09:45:54 -0500749 goto err1;
Tom Tucker377f9b22007-12-12 16:13:21 -0600750 }
751
752 /*
753 * We need to use the address from the cm_id in case the
754 * caller specified 0 for the port number.
755 */
756 sa = (struct sockaddr *)&cma_xprt->sc_cm_id->route.addr.src_addr;
757 svc_xprt_set_local(&cma_xprt->sc_xprt, sa, salen);
758
759 return &cma_xprt->sc_xprt;
Tom Tucker58e8f622008-05-06 09:45:54 -0500760
761 err1:
762 rdma_destroy_id(listen_id);
763 err0:
764 kfree(cma_xprt);
765 return ERR_PTR(ret);
Tom Tucker377f9b22007-12-12 16:13:21 -0600766}
767
768/*
769 * This is the xpo_recvfrom function for listening endpoints. Its
770 * purpose is to accept incoming connections. The CMA callback handler
771 * has already created a new transport and attached it to the new CMA
772 * ID.
773 *
774 * There is a queue of pending connections hung on the listening
775 * transport. This queue contains the new svc_xprt structure. This
776 * function takes svc_xprt structures off the accept_q and completes
777 * the connection.
778 */
779static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
780{
781 struct svcxprt_rdma *listen_rdma;
782 struct svcxprt_rdma *newxprt = NULL;
783 struct rdma_conn_param conn_param;
784 struct ib_qp_init_attr qp_attr;
785 struct ib_device_attr devattr;
Tom Tucker377f9b22007-12-12 16:13:21 -0600786 int ret;
787 int i;
788
789 listen_rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt);
790 clear_bit(XPT_CONN, &xprt->xpt_flags);
791 /* Get the next entry off the accept list */
792 spin_lock_bh(&listen_rdma->sc_lock);
793 if (!list_empty(&listen_rdma->sc_accept_q)) {
794 newxprt = list_entry(listen_rdma->sc_accept_q.next,
795 struct svcxprt_rdma, sc_accept_q);
796 list_del_init(&newxprt->sc_accept_q);
797 }
798 if (!list_empty(&listen_rdma->sc_accept_q))
799 set_bit(XPT_CONN, &listen_rdma->sc_xprt.xpt_flags);
800 spin_unlock_bh(&listen_rdma->sc_lock);
801 if (!newxprt)
802 return NULL;
803
804 dprintk("svcrdma: newxprt from accept queue = %p, cm_id=%p\n",
805 newxprt, newxprt->sc_cm_id);
806
807 ret = ib_query_device(newxprt->sc_cm_id->device, &devattr);
808 if (ret) {
809 dprintk("svcrdma: could not query device attributes on "
810 "device %p, rc=%d\n", newxprt->sc_cm_id->device, ret);
811 goto errout;
812 }
813
814 /* Qualify the transport resource defaults with the
815 * capabilities of this particular device */
816 newxprt->sc_max_sge = min((size_t)devattr.max_sge,
817 (size_t)RPCSVC_MAXPAGES);
818 newxprt->sc_max_requests = min((size_t)devattr.max_qp_wr,
819 (size_t)svcrdma_max_requests);
820 newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests;
821
822 newxprt->sc_ord = min((size_t)devattr.max_qp_rd_atom,
823 (size_t)svcrdma_ord);
824
825 newxprt->sc_pd = ib_alloc_pd(newxprt->sc_cm_id->device);
826 if (IS_ERR(newxprt->sc_pd)) {
827 dprintk("svcrdma: error creating PD for connect request\n");
828 goto errout;
829 }
830 newxprt->sc_sq_cq = ib_create_cq(newxprt->sc_cm_id->device,
831 sq_comp_handler,
832 cq_event_handler,
833 newxprt,
834 newxprt->sc_sq_depth,
835 0);
836 if (IS_ERR(newxprt->sc_sq_cq)) {
837 dprintk("svcrdma: error creating SQ CQ for connect request\n");
838 goto errout;
839 }
840 newxprt->sc_rq_cq = ib_create_cq(newxprt->sc_cm_id->device,
841 rq_comp_handler,
842 cq_event_handler,
843 newxprt,
844 newxprt->sc_max_requests,
845 0);
846 if (IS_ERR(newxprt->sc_rq_cq)) {
847 dprintk("svcrdma: error creating RQ CQ for connect request\n");
848 goto errout;
849 }
850
851 memset(&qp_attr, 0, sizeof qp_attr);
852 qp_attr.event_handler = qp_event_handler;
853 qp_attr.qp_context = &newxprt->sc_xprt;
854 qp_attr.cap.max_send_wr = newxprt->sc_sq_depth;
855 qp_attr.cap.max_recv_wr = newxprt->sc_max_requests;
856 qp_attr.cap.max_send_sge = newxprt->sc_max_sge;
857 qp_attr.cap.max_recv_sge = newxprt->sc_max_sge;
858 qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
859 qp_attr.qp_type = IB_QPT_RC;
860 qp_attr.send_cq = newxprt->sc_sq_cq;
861 qp_attr.recv_cq = newxprt->sc_rq_cq;
862 dprintk("svcrdma: newxprt->sc_cm_id=%p, newxprt->sc_pd=%p\n"
863 " cm_id->device=%p, sc_pd->device=%p\n"
864 " cap.max_send_wr = %d\n"
865 " cap.max_recv_wr = %d\n"
866 " cap.max_send_sge = %d\n"
867 " cap.max_recv_sge = %d\n",
868 newxprt->sc_cm_id, newxprt->sc_pd,
869 newxprt->sc_cm_id->device, newxprt->sc_pd->device,
870 qp_attr.cap.max_send_wr,
871 qp_attr.cap.max_recv_wr,
872 qp_attr.cap.max_send_sge,
873 qp_attr.cap.max_recv_sge);
874
875 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr);
876 if (ret) {
877 /*
878 * XXX: This is a hack. We need a xx_request_qp interface
879 * that will adjust the qp_attr's with a best-effort
880 * number
881 */
882 qp_attr.cap.max_send_sge -= 2;
883 qp_attr.cap.max_recv_sge -= 2;
884 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd,
885 &qp_attr);
886 if (ret) {
887 dprintk("svcrdma: failed to create QP, ret=%d\n", ret);
888 goto errout;
889 }
890 newxprt->sc_max_sge = qp_attr.cap.max_send_sge;
891 newxprt->sc_max_sge = qp_attr.cap.max_recv_sge;
892 newxprt->sc_sq_depth = qp_attr.cap.max_send_wr;
893 newxprt->sc_max_requests = qp_attr.cap.max_recv_wr;
894 }
895 newxprt->sc_qp = newxprt->sc_cm_id->qp;
896
897 /* Register all of physical memory */
898 newxprt->sc_phys_mr = ib_get_dma_mr(newxprt->sc_pd,
899 IB_ACCESS_LOCAL_WRITE |
900 IB_ACCESS_REMOTE_WRITE);
901 if (IS_ERR(newxprt->sc_phys_mr)) {
902 dprintk("svcrdma: Failed to create DMA MR ret=%d\n", ret);
903 goto errout;
904 }
905
906 /* Post receive buffers */
907 for (i = 0; i < newxprt->sc_max_requests; i++) {
908 ret = svc_rdma_post_recv(newxprt);
909 if (ret) {
910 dprintk("svcrdma: failure posting receive buffers\n");
911 goto errout;
912 }
913 }
914
915 /* Swap out the handler */
916 newxprt->sc_cm_id->event_handler = rdma_cma_handler;
917
Tom Tuckeraf261af2008-05-07 13:52:42 -0500918 /*
919 * Arm the CQs for the SQ and RQ before accepting so we can't
920 * miss the first message
921 */
922 ib_req_notify_cq(newxprt->sc_sq_cq, IB_CQ_NEXT_COMP);
923 ib_req_notify_cq(newxprt->sc_rq_cq, IB_CQ_NEXT_COMP);
924
Tom Tucker377f9b22007-12-12 16:13:21 -0600925 /* Accept Connection */
926 set_bit(RDMAXPRT_CONN_PENDING, &newxprt->sc_flags);
927 memset(&conn_param, 0, sizeof conn_param);
928 conn_param.responder_resources = 0;
929 conn_param.initiator_depth = newxprt->sc_ord;
930 ret = rdma_accept(newxprt->sc_cm_id, &conn_param);
931 if (ret) {
932 dprintk("svcrdma: failed to accept new connection, ret=%d\n",
933 ret);
934 goto errout;
935 }
936
937 dprintk("svcrdma: new connection %p accepted with the following "
938 "attributes:\n"
939 " local_ip : %d.%d.%d.%d\n"
940 " local_port : %d\n"
941 " remote_ip : %d.%d.%d.%d\n"
942 " remote_port : %d\n"
943 " max_sge : %d\n"
944 " sq_depth : %d\n"
945 " max_requests : %d\n"
946 " ord : %d\n",
947 newxprt,
948 NIPQUAD(((struct sockaddr_in *)&newxprt->sc_cm_id->
949 route.addr.src_addr)->sin_addr.s_addr),
950 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id->
951 route.addr.src_addr)->sin_port),
952 NIPQUAD(((struct sockaddr_in *)&newxprt->sc_cm_id->
953 route.addr.dst_addr)->sin_addr.s_addr),
954 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id->
955 route.addr.dst_addr)->sin_port),
956 newxprt->sc_max_sge,
957 newxprt->sc_sq_depth,
958 newxprt->sc_max_requests,
959 newxprt->sc_ord);
960
Tom Tucker377f9b22007-12-12 16:13:21 -0600961 return &newxprt->sc_xprt;
962
963 errout:
964 dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret);
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400965 /* Take a reference in case the DTO handler runs */
966 svc_xprt_get(&newxprt->sc_xprt);
Tom Tucker17113862008-05-01 11:13:50 -0500967 if (newxprt->sc_qp && !IS_ERR(newxprt->sc_qp))
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400968 ib_destroy_qp(newxprt->sc_qp);
Tom Tucker377f9b22007-12-12 16:13:21 -0600969 rdma_destroy_id(newxprt->sc_cm_id);
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400970 /* This call to put will destroy the transport */
971 svc_xprt_put(&newxprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600972 return NULL;
973}
974
Tom Tucker377f9b22007-12-12 16:13:21 -0600975static void svc_rdma_release_rqst(struct svc_rqst *rqstp)
976{
Tom Tucker377f9b22007-12-12 16:13:21 -0600977}
978
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400979/*
Tom Tucker17113862008-05-01 11:13:50 -0500980 * When connected, an svc_xprt has at least two references:
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400981 *
982 * - A reference held by the cm_id between the ESTABLISHED and
983 * DISCONNECTED events. If the remote peer disconnected first, this
984 * reference could be gone.
985 *
986 * - A reference held by the svc_recv code that called this function
987 * as part of close processing.
988 *
Tom Tucker17113862008-05-01 11:13:50 -0500989 * At a minimum one references should still be held.
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400990 */
Tom Tucker377f9b22007-12-12 16:13:21 -0600991static void svc_rdma_detach(struct svc_xprt *xprt)
992{
993 struct svcxprt_rdma *rdma =
994 container_of(xprt, struct svcxprt_rdma, sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600995 dprintk("svc: svc_rdma_detach(%p)\n", xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -0600996
Tom Tuckerc48cbb42008-03-11 14:31:39 -0400997 /* Disconnect and flush posted WQE */
998 rdma_disconnect(rdma->sc_cm_id);
Tom Tucker377f9b22007-12-12 16:13:21 -0600999}
1000
Tom Tucker8da91ea2008-04-30 22:00:46 -05001001static void __svc_rdma_free(struct work_struct *work)
Tom Tucker377f9b22007-12-12 16:13:21 -06001002{
Tom Tucker8da91ea2008-04-30 22:00:46 -05001003 struct svcxprt_rdma *rdma =
1004 container_of(work, struct svcxprt_rdma, sc_work);
Tom Tucker377f9b22007-12-12 16:13:21 -06001005 dprintk("svcrdma: svc_rdma_free(%p)\n", rdma);
Tom Tucker8da91ea2008-04-30 22:00:46 -05001006
Tom Tuckerc48cbb42008-03-11 14:31:39 -04001007 /* We should only be called from kref_put */
Tom Tucker8da91ea2008-04-30 22:00:46 -05001008 BUG_ON(atomic_read(&rdma->sc_xprt.xpt_ref.refcount) != 0);
1009
Tom Tucker356d0a12008-05-01 11:25:02 -05001010 /*
1011 * Destroy queued, but not processed read completions. Note
1012 * that this cleanup has to be done before destroying the
1013 * cm_id because the device ptr is needed to unmap the dma in
1014 * svc_rdma_put_context.
1015 */
1016 spin_lock_bh(&rdma->sc_read_complete_lock);
1017 while (!list_empty(&rdma->sc_read_complete_q)) {
1018 struct svc_rdma_op_ctxt *ctxt;
1019 ctxt = list_entry(rdma->sc_read_complete_q.next,
1020 struct svc_rdma_op_ctxt,
1021 dto_q);
1022 list_del_init(&ctxt->dto_q);
1023 svc_rdma_put_context(ctxt, 1);
1024 }
1025 spin_unlock_bh(&rdma->sc_read_complete_lock);
1026
1027 /* Destroy queued, but not processed recv completions */
1028 spin_lock_bh(&rdma->sc_rq_dto_lock);
1029 while (!list_empty(&rdma->sc_rq_dto_q)) {
1030 struct svc_rdma_op_ctxt *ctxt;
1031 ctxt = list_entry(rdma->sc_rq_dto_q.next,
1032 struct svc_rdma_op_ctxt,
1033 dto_q);
1034 list_del_init(&ctxt->dto_q);
1035 svc_rdma_put_context(ctxt, 1);
1036 }
1037 spin_unlock_bh(&rdma->sc_rq_dto_lock);
1038
1039 /* Warn if we leaked a resource or under-referenced */
1040 WARN_ON(atomic_read(&rdma->sc_ctxt_used) != 0);
1041
Tom Tucker17113862008-05-01 11:13:50 -05001042 /* Destroy the QP if present (not a listener) */
1043 if (rdma->sc_qp && !IS_ERR(rdma->sc_qp))
1044 ib_destroy_qp(rdma->sc_qp);
1045
Tom Tuckerc48cbb42008-03-11 14:31:39 -04001046 if (rdma->sc_sq_cq && !IS_ERR(rdma->sc_sq_cq))
1047 ib_destroy_cq(rdma->sc_sq_cq);
1048
1049 if (rdma->sc_rq_cq && !IS_ERR(rdma->sc_rq_cq))
1050 ib_destroy_cq(rdma->sc_rq_cq);
1051
1052 if (rdma->sc_phys_mr && !IS_ERR(rdma->sc_phys_mr))
1053 ib_dereg_mr(rdma->sc_phys_mr);
1054
1055 if (rdma->sc_pd && !IS_ERR(rdma->sc_pd))
1056 ib_dealloc_pd(rdma->sc_pd);
1057
Tom Tucker356d0a12008-05-01 11:25:02 -05001058 /* Destroy the CM ID */
1059 rdma_destroy_id(rdma->sc_cm_id);
1060
Tom Tucker87407672008-04-30 20:44:39 -05001061 destroy_context_cache(rdma);
Tom Tucker377f9b22007-12-12 16:13:21 -06001062 kfree(rdma);
1063}
1064
Tom Tucker8da91ea2008-04-30 22:00:46 -05001065static void svc_rdma_free(struct svc_xprt *xprt)
1066{
1067 struct svcxprt_rdma *rdma =
1068 container_of(xprt, struct svcxprt_rdma, sc_xprt);
1069 INIT_WORK(&rdma->sc_work, __svc_rdma_free);
1070 schedule_work(&rdma->sc_work);
1071}
1072
Tom Tucker377f9b22007-12-12 16:13:21 -06001073static int svc_rdma_has_wspace(struct svc_xprt *xprt)
1074{
1075 struct svcxprt_rdma *rdma =
1076 container_of(xprt, struct svcxprt_rdma, sc_xprt);
1077
1078 /*
1079 * If there are fewer SQ WR available than required to send a
1080 * simple response, return false.
1081 */
1082 if ((rdma->sc_sq_depth - atomic_read(&rdma->sc_sq_count) < 3))
1083 return 0;
1084
1085 /*
1086 * ...or there are already waiters on the SQ,
1087 * return false.
1088 */
1089 if (waitqueue_active(&rdma->sc_send_wait))
1090 return 0;
1091
1092 /* Otherwise return true. */
1093 return 1;
1094}
1095
1096int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr)
1097{
1098 struct ib_send_wr *bad_wr;
1099 int ret;
1100
1101 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
Tom Tucker9d6347a2008-04-25 15:51:27 -05001102 return -ENOTCONN;
Tom Tucker377f9b22007-12-12 16:13:21 -06001103
1104 BUG_ON(wr->send_flags != IB_SEND_SIGNALED);
1105 BUG_ON(((struct svc_rdma_op_ctxt *)(unsigned long)wr->wr_id)->wr_op !=
1106 wr->opcode);
1107 /* If the SQ is full, wait until an SQ entry is available */
1108 while (1) {
1109 spin_lock_bh(&xprt->sc_lock);
1110 if (xprt->sc_sq_depth == atomic_read(&xprt->sc_sq_count)) {
1111 spin_unlock_bh(&xprt->sc_lock);
1112 atomic_inc(&rdma_stat_sq_starve);
Tom Tuckerdbcd00e2008-05-06 11:33:11 -05001113
1114 /* See if we can opportunistically reap SQ WR to make room */
Tom Tucker377f9b22007-12-12 16:13:21 -06001115 sq_cq_reap(xprt);
1116
1117 /* Wait until SQ WR available if SQ still full */
1118 wait_event(xprt->sc_send_wait,
1119 atomic_read(&xprt->sc_sq_count) <
1120 xprt->sc_sq_depth);
Tom Tucker830bb592008-03-11 12:44:27 -05001121 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
1122 return 0;
Tom Tucker377f9b22007-12-12 16:13:21 -06001123 continue;
1124 }
1125 /* Bumped used SQ WR count and post */
Tom Tucker0905c0f2008-05-01 10:49:03 -05001126 svc_xprt_get(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -06001127 ret = ib_post_send(xprt->sc_qp, wr, &bad_wr);
1128 if (!ret)
1129 atomic_inc(&xprt->sc_sq_count);
Tom Tucker0905c0f2008-05-01 10:49:03 -05001130 else {
1131 svc_xprt_put(&xprt->sc_xprt);
Tom Tucker377f9b22007-12-12 16:13:21 -06001132 dprintk("svcrdma: failed to post SQ WR rc=%d, "
1133 "sc_sq_count=%d, sc_sq_depth=%d\n",
1134 ret, atomic_read(&xprt->sc_sq_count),
1135 xprt->sc_sq_depth);
Tom Tucker0905c0f2008-05-01 10:49:03 -05001136 }
Tom Tucker377f9b22007-12-12 16:13:21 -06001137 spin_unlock_bh(&xprt->sc_lock);
1138 break;
1139 }
1140 return ret;
1141}
1142
Tom Tucker008fdbc2008-05-07 15:47:42 -05001143void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp,
1144 enum rpcrdma_errcode err)
Tom Tucker377f9b22007-12-12 16:13:21 -06001145{
1146 struct ib_send_wr err_wr;
1147 struct ib_sge sge;
1148 struct page *p;
1149 struct svc_rdma_op_ctxt *ctxt;
1150 u32 *va;
1151 int length;
1152 int ret;
1153
1154 p = svc_rdma_get_page();
1155 va = page_address(p);
1156
1157 /* XDR encode error */
1158 length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va);
1159
1160 /* Prepare SGE for local address */
1161 sge.addr = ib_dma_map_page(xprt->sc_cm_id->device,
1162 p, 0, PAGE_SIZE, DMA_FROM_DEVICE);
1163 sge.lkey = xprt->sc_phys_mr->lkey;
1164 sge.length = length;
1165
1166 ctxt = svc_rdma_get_context(xprt);
1167 ctxt->count = 1;
1168 ctxt->pages[0] = p;
1169
1170 /* Prepare SEND WR */
1171 memset(&err_wr, 0, sizeof err_wr);
1172 ctxt->wr_op = IB_WR_SEND;
1173 err_wr.wr_id = (unsigned long)ctxt;
1174 err_wr.sg_list = &sge;
1175 err_wr.num_sge = 1;
1176 err_wr.opcode = IB_WR_SEND;
1177 err_wr.send_flags = IB_SEND_SIGNALED;
1178
1179 /* Post It */
1180 ret = svc_rdma_send(xprt, &err_wr);
1181 if (ret) {
Tom Tucker008fdbc2008-05-07 15:47:42 -05001182 dprintk("svcrdma: Error %d posting send for protocol error\n",
1183 ret);
Tom Tucker377f9b22007-12-12 16:13:21 -06001184 svc_rdma_put_context(ctxt, 1);
1185 }
Tom Tucker377f9b22007-12-12 16:13:21 -06001186}