2 * Copyright (c) 2005-2007 Network Appliance, Inc. All rights reserved.
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
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
14 * Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
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.
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
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.
39 * Author: Tom Tucker <tom@opengridcomputing.com>
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>
50 #define RPCDBG_FACILITY RPCDBG_SVCXPRT
52 static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
53 struct sockaddr *sa, int salen,
55 static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt);
56 static void svc_rdma_release_rqst(struct svc_rqst *);
57 static void dto_tasklet_func(unsigned long data);
58 static void svc_rdma_detach(struct svc_xprt *xprt);
59 static void svc_rdma_free(struct svc_xprt *xprt);
60 static int svc_rdma_has_wspace(struct svc_xprt *xprt);
61 static void rq_cq_reap(struct svcxprt_rdma *xprt);
62 static void sq_cq_reap(struct svcxprt_rdma *xprt);
64 DECLARE_TASKLET(dto_tasklet, dto_tasklet_func, 0UL);
65 static DEFINE_SPINLOCK(dto_lock);
66 static LIST_HEAD(dto_xprt_q);
68 static 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,
80 struct svc_xprt_class svc_rdma_class = {
82 .xcl_owner = THIS_MODULE,
83 .xcl_ops = &svc_rdma_ops,
84 .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
87 static int rdma_bump_context_cache(struct svcxprt_rdma *xprt)
91 struct svc_rdma_op_ctxt *ctxt;
93 target = min(xprt->sc_ctxt_cnt + xprt->sc_ctxt_bump,
96 spin_lock_bh(&xprt->sc_ctxt_lock);
97 while (xprt->sc_ctxt_cnt < target) {
99 spin_unlock_bh(&xprt->sc_ctxt_lock);
101 ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL);
103 spin_lock_bh(&xprt->sc_ctxt_lock);
106 INIT_LIST_HEAD(&ctxt->free_list);
107 list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
109 /* kmalloc failed...give up for now */
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);
120 struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt)
122 struct svc_rdma_op_ctxt *ctxt;
125 spin_lock_bh(&xprt->sc_ctxt_lock);
126 if (unlikely(list_empty(&xprt->sc_ctxt_free))) {
127 /* Try to bump my cache. */
128 spin_unlock_bh(&xprt->sc_ctxt_lock);
130 if (rdma_bump_context_cache(xprt))
133 printk(KERN_INFO "svcrdma: sleeping waiting for "
134 "context memory on xprt=%p\n",
136 schedule_timeout_uninterruptible(msecs_to_jiffies(500));
139 ctxt = list_entry(xprt->sc_ctxt_free.next,
140 struct svc_rdma_op_ctxt,
142 list_del_init(&ctxt->free_list);
143 spin_unlock_bh(&xprt->sc_ctxt_lock);
145 INIT_LIST_HEAD(&ctxt->dto_q);
147 atomic_inc(&xprt->sc_ctxt_used);
153 void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages)
155 struct svcxprt_rdma *xprt;
161 for (i = 0; i < ctxt->count; i++)
162 put_page(ctxt->pages[i]);
164 for (i = 0; i < ctxt->count; i++)
165 ib_dma_unmap_single(xprt->sc_cm_id->device,
170 spin_lock_bh(&xprt->sc_ctxt_lock);
171 list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
172 spin_unlock_bh(&xprt->sc_ctxt_lock);
173 atomic_dec(&xprt->sc_ctxt_used);
176 /* Temporary NFS request map cache. Created in svc_rdma.c */
177 extern struct kmem_cache *svc_rdma_map_cachep;
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.
184 struct svc_rdma_req_map *svc_rdma_get_req_map(void)
186 struct svc_rdma_req_map *map;
188 map = kmem_cache_alloc(svc_rdma_map_cachep, GFP_KERNEL);
191 schedule_timeout_uninterruptible(msecs_to_jiffies(500));
197 void svc_rdma_put_req_map(struct svc_rdma_req_map *map)
199 kmem_cache_free(svc_rdma_map_cachep, map);
202 /* ib_cq event handler */
203 static void cq_event_handler(struct ib_event *event, void *context)
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);
211 /* QP event handler */
212 static void qp_event_handler(struct ib_event *event, void *context)
214 struct svc_xprt *xprt = context;
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);
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:
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);
241 * Data Transfer Operation Tasklet
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.
249 static void dto_tasklet_func(unsigned long data)
251 struct svcxprt_rdma *xprt;
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);
264 svc_xprt_put(&xprt->sc_xprt);
265 spin_lock_irqsave(&dto_lock, flags);
267 spin_unlock_irqrestore(&dto_lock, flags);
271 * Receive Queue Completion Handler
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
276 static void rq_comp_handler(struct ib_cq *cq, void *cq_context)
278 struct svcxprt_rdma *xprt = cq_context;
281 /* Guard against unconditional flush call for destroyed QP */
282 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0)
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
290 set_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags);
293 * If this transport is not already on the DTO transport queue,
296 spin_lock_irqsave(&dto_lock, flags);
297 if (list_empty(&xprt->sc_dto_q)) {
298 svc_xprt_get(&xprt->sc_xprt);
299 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
301 spin_unlock_irqrestore(&dto_lock, flags);
303 /* Tasklet does all the work to avoid irqsave locks. */
304 tasklet_schedule(&dto_tasklet);
308 * rq_cq_reap - Process the RQ CQ.
310 * Take all completing WC off the CQE and enqueue the associated DTO
311 * context on the dto_q for the transport.
313 * Note that caller must hold a transport reference.
315 static void rq_cq_reap(struct svcxprt_rdma *xprt)
319 struct svc_rdma_op_ctxt *ctxt = NULL;
321 if (!test_and_clear_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags))
324 ib_req_notify_cq(xprt->sc_rq_cq, IB_CQ_NEXT_COMP);
325 atomic_inc(&rdma_stat_rq_poll);
327 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 */
333 dprintk("svcrdma: transport closing putting ctxt %p\n", ctxt);
334 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
335 svc_rdma_put_context(ctxt, 1);
336 svc_xprt_put(&xprt->sc_xprt);
339 spin_lock_bh(&xprt->sc_rq_dto_lock);
340 list_add_tail(&ctxt->dto_q, &xprt->sc_rq_dto_q);
341 spin_unlock_bh(&xprt->sc_rq_dto_lock);
342 svc_xprt_put(&xprt->sc_xprt);
346 atomic_inc(&rdma_stat_rq_prod);
348 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
350 * If data arrived before established event,
351 * don't enqueue. This defers RPC I/O until the
352 * RDMA connection is complete.
354 if (!test_bit(RDMAXPRT_CONN_PENDING, &xprt->sc_flags))
355 svc_xprt_enqueue(&xprt->sc_xprt);
359 * Send Queue Completion Handler - potentially called on interrupt context.
361 * Note that caller must hold a transport reference.
363 static void sq_cq_reap(struct svcxprt_rdma *xprt)
365 struct svc_rdma_op_ctxt *ctxt = NULL;
367 struct ib_cq *cq = xprt->sc_sq_cq;
371 if (!test_and_clear_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags))
374 ib_req_notify_cq(xprt->sc_sq_cq, IB_CQ_NEXT_COMP);
375 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;
380 if (wc.status != IB_WC_SUCCESS)
381 /* Close the transport */
382 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
384 /* Decrement used SQ WR count */
385 atomic_dec(&xprt->sc_sq_count);
386 wake_up(&xprt->sc_send_wait);
388 switch (ctxt->wr_op) {
390 case IB_WR_RDMA_WRITE:
391 svc_rdma_put_context(ctxt, 1);
394 case IB_WR_RDMA_READ:
395 if (test_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags)) {
396 struct svc_rdma_op_ctxt *read_hdr = ctxt->read_hdr;
398 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
399 spin_lock_bh(&xprt->sc_read_complete_lock);
400 list_add_tail(&read_hdr->dto_q,
401 &xprt->sc_read_complete_q);
402 spin_unlock_bh(&xprt->sc_read_complete_lock);
403 svc_xprt_enqueue(&xprt->sc_xprt);
405 svc_rdma_put_context(ctxt, 0);
409 printk(KERN_ERR "svcrdma: unexpected completion type, "
410 "opcode=%d, status=%d\n",
411 wc.opcode, wc.status);
414 svc_xprt_put(&xprt->sc_xprt);
418 atomic_inc(&rdma_stat_sq_prod);
421 static void sq_comp_handler(struct ib_cq *cq, void *cq_context)
423 struct svcxprt_rdma *xprt = cq_context;
426 /* Guard against unconditional flush call for destroyed QP */
427 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0)
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
435 set_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags);
438 * If this transport is not already on the DTO transport queue,
441 spin_lock_irqsave(&dto_lock, flags);
442 if (list_empty(&xprt->sc_dto_q)) {
443 svc_xprt_get(&xprt->sc_xprt);
444 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
446 spin_unlock_irqrestore(&dto_lock, flags);
448 /* Tasklet does all the work to avoid irqsave locks. */
449 tasklet_schedule(&dto_tasklet);
452 static void create_context_cache(struct svcxprt_rdma *xprt,
453 int ctxt_count, int ctxt_bump, int ctxt_max)
455 struct svc_rdma_op_ctxt *ctxt;
458 xprt->sc_ctxt_max = ctxt_max;
459 xprt->sc_ctxt_bump = ctxt_bump;
460 xprt->sc_ctxt_cnt = 0;
461 atomic_set(&xprt->sc_ctxt_used, 0);
463 INIT_LIST_HEAD(&xprt->sc_ctxt_free);
464 for (i = 0; i < ctxt_count; i++) {
465 ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL);
467 INIT_LIST_HEAD(&ctxt->free_list);
468 list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
474 static void destroy_context_cache(struct svcxprt_rdma *xprt)
476 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,
481 list_del_init(&ctxt->free_list);
486 static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
489 struct svcxprt_rdma *cma_xprt = kzalloc(sizeof *cma_xprt, GFP_KERNEL);
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);
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);
505 cma_xprt->sc_ord = svcrdma_ord;
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);
513 int reqs = cma_xprt->sc_max_requests;
514 create_context_cache(cma_xprt,
515 reqs << 1, /* starting size */
516 reqs, /* bump amount */
518 cma_xprt->sc_sq_depth +
519 RPCRDMA_MAX_THREADS + 1); /* max */
520 if (list_empty(&cma_xprt->sc_ctxt_free)) {
524 clear_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
526 set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
531 struct page *svc_rdma_get_page(void)
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 "
539 schedule_timeout_uninterruptible(msecs_to_jiffies(1000));
544 int svc_rdma_post_recv(struct svcxprt_rdma *xprt)
546 struct ib_recv_wr recv_wr, *bad_recv_wr;
547 struct svc_rdma_op_ctxt *ctxt;
554 ctxt = svc_rdma_get_context(xprt);
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,
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;
569 ctxt->count = sge_no;
571 recv_wr.sg_list = &ctxt->sge[0];
572 recv_wr.num_sge = ctxt->count;
573 recv_wr.wr_id = (u64)(unsigned long)ctxt;
575 svc_xprt_get(&xprt->sc_xprt);
576 ret = ib_post_recv(xprt->sc_qp, &recv_wr, &bad_recv_wr);
578 svc_xprt_put(&xprt->sc_xprt);
579 svc_rdma_put_context(ctxt, 1);
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.
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
595 static void handle_connect_req(struct rdma_cm_id *new_cma_id)
597 struct svcxprt_rdma *listen_xprt = new_cma_id->context;
598 struct svcxprt_rdma *newxprt;
601 /* Create a new transport */
602 newxprt = rdma_create_xprt(listen_xprt->sc_xprt.xpt_server, 0);
604 dprintk("svcrdma: failed to create new transport\n");
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);
612 /* 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));
619 * Enqueue the new transport on the accept queue of the listening
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);
627 * Can't use svc_xprt_received here because we are not on a
630 set_bit(XPT_CONN, &listen_xprt->sc_xprt.xpt_flags);
631 svc_xprt_enqueue(&listen_xprt->sc_xprt);
635 * Handles events generated on the listening endpoint. These events will be
636 * either be incoming connect requests or adapter removal events.
638 static int rdma_listen_handler(struct rdma_cm_id *cma_id,
639 struct rdma_cm_event *event)
641 struct svcxprt_rdma *xprt = cma_id->context;
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);
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);
657 case RDMA_CM_EVENT_DEVICE_REMOVAL:
658 dprintk("svcrdma: Device removal xprt=%p, cm_id=%p\n",
661 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
665 dprintk("svcrdma: Unexpected event on listening endpoint %p, "
666 "event=%d\n", cma_id, event->event);
673 static int rdma_cma_handler(struct rdma_cm_id *cma_id,
674 struct rdma_cm_event *event)
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 */
683 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);
688 case RDMA_CM_EVENT_DISCONNECTED:
689 dprintk("svcrdma: Disconnect on DTO xprt=%p, cm_id=%p\n",
692 set_bit(XPT_CLOSE, &xprt->xpt_flags);
693 svc_xprt_enqueue(xprt);
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);
701 set_bit(XPT_CLOSE, &xprt->xpt_flags);
702 svc_xprt_enqueue(xprt);
706 dprintk("svcrdma: Unexpected event on DTO endpoint %p, "
707 "event=%d\n", cma_id, event->event);
714 * Create a listening RDMA service endpoint.
716 static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
717 struct sockaddr *sa, int salen,
720 struct rdma_cm_id *listen_id;
721 struct svcxprt_rdma *cma_xprt;
722 struct svc_xprt *xprt;
725 dprintk("svcrdma: Creating RDMA socket\n");
727 cma_xprt = rdma_create_xprt(serv, 1);
729 return ERR_PTR(-ENOMEM);
730 xprt = &cma_xprt->sc_xprt;
732 listen_id = rdma_create_id(rdma_listen_handler, cma_xprt, RDMA_PS_TCP);
733 if (IS_ERR(listen_id)) {
734 ret = PTR_ERR(listen_id);
735 dprintk("svcrdma: rdma_create_id failed = %d\n", ret);
739 ret = rdma_bind_addr(listen_id, sa);
741 dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret);
744 cma_xprt->sc_cm_id = listen_id;
746 ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG);
748 dprintk("svcrdma: rdma_listen failed = %d\n", ret);
753 * We need to use the address from the cm_id in case the
754 * caller specified 0 for the port number.
756 sa = (struct sockaddr *)&cma_xprt->sc_cm_id->route.addr.src_addr;
757 svc_xprt_set_local(&cma_xprt->sc_xprt, sa, salen);
759 return &cma_xprt->sc_xprt;
762 rdma_destroy_id(listen_id);
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
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
779 static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
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;
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);
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);
804 dprintk("svcrdma: newxprt from accept queue = %p, cm_id=%p\n",
805 newxprt, newxprt->sc_cm_id);
807 ret = ib_query_device(newxprt->sc_cm_id->device, &devattr);
809 dprintk("svcrdma: could not query device attributes on "
810 "device %p, rc=%d\n", newxprt->sc_cm_id->device, ret);
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;
822 newxprt->sc_ord = min((size_t)devattr.max_qp_rd_atom,
823 (size_t)svcrdma_ord);
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");
830 newxprt->sc_sq_cq = ib_create_cq(newxprt->sc_cm_id->device,
834 newxprt->sc_sq_depth,
836 if (IS_ERR(newxprt->sc_sq_cq)) {
837 dprintk("svcrdma: error creating SQ CQ for connect request\n");
840 newxprt->sc_rq_cq = ib_create_cq(newxprt->sc_cm_id->device,
844 newxprt->sc_max_requests,
846 if (IS_ERR(newxprt->sc_rq_cq)) {
847 dprintk("svcrdma: error creating RQ CQ for connect request\n");
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);
875 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr);
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
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,
887 dprintk("svcrdma: failed to create QP, ret=%d\n", ret);
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;
895 newxprt->sc_qp = newxprt->sc_cm_id->qp;
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);
906 /* Post receive buffers */
907 for (i = 0; i < newxprt->sc_max_requests; i++) {
908 ret = svc_rdma_post_recv(newxprt);
910 dprintk("svcrdma: failure posting receive buffers\n");
915 /* Swap out the handler */
916 newxprt->sc_cm_id->event_handler = rdma_cma_handler;
919 * Arm the CQs for the SQ and RQ before accepting so we can't
920 * miss the first message
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);
925 /* 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);
932 dprintk("svcrdma: failed to accept new connection, ret=%d\n",
937 dprintk("svcrdma: new connection %p accepted with the following "
939 " local_ip : %d.%d.%d.%d\n"
941 " remote_ip : %d.%d.%d.%d\n"
942 " remote_port : %d\n"
945 " max_requests : %d\n"
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),
957 newxprt->sc_sq_depth,
958 newxprt->sc_max_requests,
961 return &newxprt->sc_xprt;
964 dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret);
965 /* Take a reference in case the DTO handler runs */
966 svc_xprt_get(&newxprt->sc_xprt);
967 if (newxprt->sc_qp && !IS_ERR(newxprt->sc_qp))
968 ib_destroy_qp(newxprt->sc_qp);
969 rdma_destroy_id(newxprt->sc_cm_id);
970 /* This call to put will destroy the transport */
971 svc_xprt_put(&newxprt->sc_xprt);
975 static void svc_rdma_release_rqst(struct svc_rqst *rqstp)
980 * When connected, an svc_xprt has at least two references:
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.
986 * - A reference held by the svc_recv code that called this function
987 * as part of close processing.
989 * At a minimum one references should still be held.
991 static void svc_rdma_detach(struct svc_xprt *xprt)
993 struct svcxprt_rdma *rdma =
994 container_of(xprt, struct svcxprt_rdma, sc_xprt);
995 dprintk("svc: svc_rdma_detach(%p)\n", xprt);
997 /* Disconnect and flush posted WQE */
998 rdma_disconnect(rdma->sc_cm_id);
1001 static void __svc_rdma_free(struct work_struct *work)
1003 struct svcxprt_rdma *rdma =
1004 container_of(work, struct svcxprt_rdma, sc_work);
1005 dprintk("svcrdma: svc_rdma_free(%p)\n", rdma);
1007 /* We should only be called from kref_put */
1008 BUG_ON(atomic_read(&rdma->sc_xprt.xpt_ref.refcount) != 0);
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.
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,
1022 list_del_init(&ctxt->dto_q);
1023 svc_rdma_put_context(ctxt, 1);
1025 spin_unlock_bh(&rdma->sc_read_complete_lock);
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,
1034 list_del_init(&ctxt->dto_q);
1035 svc_rdma_put_context(ctxt, 1);
1037 spin_unlock_bh(&rdma->sc_rq_dto_lock);
1039 /* Warn if we leaked a resource or under-referenced */
1040 WARN_ON(atomic_read(&rdma->sc_ctxt_used) != 0);
1042 /* 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);
1046 if (rdma->sc_sq_cq && !IS_ERR(rdma->sc_sq_cq))
1047 ib_destroy_cq(rdma->sc_sq_cq);
1049 if (rdma->sc_rq_cq && !IS_ERR(rdma->sc_rq_cq))
1050 ib_destroy_cq(rdma->sc_rq_cq);
1052 if (rdma->sc_phys_mr && !IS_ERR(rdma->sc_phys_mr))
1053 ib_dereg_mr(rdma->sc_phys_mr);
1055 if (rdma->sc_pd && !IS_ERR(rdma->sc_pd))
1056 ib_dealloc_pd(rdma->sc_pd);
1058 /* Destroy the CM ID */
1059 rdma_destroy_id(rdma->sc_cm_id);
1061 destroy_context_cache(rdma);
1065 static void svc_rdma_free(struct svc_xprt *xprt)
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);
1073 static int svc_rdma_has_wspace(struct svc_xprt *xprt)
1075 struct svcxprt_rdma *rdma =
1076 container_of(xprt, struct svcxprt_rdma, sc_xprt);
1079 * If there are fewer SQ WR available than required to send a
1080 * simple response, return false.
1082 if ((rdma->sc_sq_depth - atomic_read(&rdma->sc_sq_count) < 3))
1086 * ...or there are already waiters on the SQ,
1089 if (waitqueue_active(&rdma->sc_send_wait))
1092 /* Otherwise return true. */
1096 int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr)
1098 struct ib_send_wr *bad_wr;
1101 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
1104 BUG_ON(wr->send_flags != IB_SEND_SIGNALED);
1105 BUG_ON(((struct svc_rdma_op_ctxt *)(unsigned long)wr->wr_id)->wr_op !=
1107 /* If the SQ is full, wait until an SQ entry is available */
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);
1114 /* See if we can opportunistically reap SQ WR to make room */
1117 /* Wait until SQ WR available if SQ still full */
1118 wait_event(xprt->sc_send_wait,
1119 atomic_read(&xprt->sc_sq_count) <
1121 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
1125 /* Bumped used SQ WR count and post */
1126 svc_xprt_get(&xprt->sc_xprt);
1127 ret = ib_post_send(xprt->sc_qp, wr, &bad_wr);
1129 atomic_inc(&xprt->sc_sq_count);
1131 svc_xprt_put(&xprt->sc_xprt);
1132 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),
1137 spin_unlock_bh(&xprt->sc_lock);
1143 void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp,
1144 enum rpcrdma_errcode err)
1146 struct ib_send_wr err_wr;
1149 struct svc_rdma_op_ctxt *ctxt;
1154 p = svc_rdma_get_page();
1155 va = page_address(p);
1157 /* XDR encode error */
1158 length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va);
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;
1166 ctxt = svc_rdma_get_context(xprt);
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;
1176 err_wr.opcode = IB_WR_SEND;
1177 err_wr.send_flags = IB_SEND_SIGNALED;
1180 ret = svc_rdma_send(xprt, &err_wr);
1182 dprintk("svcrdma: Error %d posting send for protocol error\n",
1184 svc_rdma_put_context(ctxt, 1);