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 static void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt)
155 struct svcxprt_rdma *xprt = ctxt->xprt;
157 for (i = 0; i < ctxt->count && ctxt->sge[i].length; i++) {
158 atomic_dec(&xprt->sc_dma_used);
159 ib_dma_unmap_single(xprt->sc_cm_id->device,
166 void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages)
168 struct svcxprt_rdma *xprt;
174 for (i = 0; i < ctxt->count; i++)
175 put_page(ctxt->pages[i]);
177 spin_lock_bh(&xprt->sc_ctxt_lock);
178 list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
179 spin_unlock_bh(&xprt->sc_ctxt_lock);
180 atomic_dec(&xprt->sc_ctxt_used);
183 /* Temporary NFS request map cache. Created in svc_rdma.c */
184 extern struct kmem_cache *svc_rdma_map_cachep;
187 * Temporary NFS req mappings are shared across all transport
188 * instances. These are short lived and should be bounded by the number
189 * of concurrent server threads * depth of the SQ.
191 struct svc_rdma_req_map *svc_rdma_get_req_map(void)
193 struct svc_rdma_req_map *map;
195 map = kmem_cache_alloc(svc_rdma_map_cachep, GFP_KERNEL);
198 schedule_timeout_uninterruptible(msecs_to_jiffies(500));
204 void svc_rdma_put_req_map(struct svc_rdma_req_map *map)
206 kmem_cache_free(svc_rdma_map_cachep, map);
209 /* ib_cq event handler */
210 static void cq_event_handler(struct ib_event *event, void *context)
212 struct svc_xprt *xprt = context;
213 dprintk("svcrdma: received CQ event id=%d, context=%p\n",
214 event->event, context);
215 set_bit(XPT_CLOSE, &xprt->xpt_flags);
218 /* QP event handler */
219 static void qp_event_handler(struct ib_event *event, void *context)
221 struct svc_xprt *xprt = context;
223 switch (event->event) {
224 /* These are considered benign events */
225 case IB_EVENT_PATH_MIG:
226 case IB_EVENT_COMM_EST:
227 case IB_EVENT_SQ_DRAINED:
228 case IB_EVENT_QP_LAST_WQE_REACHED:
229 dprintk("svcrdma: QP event %d received for QP=%p\n",
230 event->event, event->element.qp);
232 /* These are considered fatal events */
233 case IB_EVENT_PATH_MIG_ERR:
234 case IB_EVENT_QP_FATAL:
235 case IB_EVENT_QP_REQ_ERR:
236 case IB_EVENT_QP_ACCESS_ERR:
237 case IB_EVENT_DEVICE_FATAL:
239 dprintk("svcrdma: QP ERROR event %d received for QP=%p, "
240 "closing transport\n",
241 event->event, event->element.qp);
242 set_bit(XPT_CLOSE, &xprt->xpt_flags);
248 * Data Transfer Operation Tasklet
250 * Walks a list of transports with I/O pending, removing entries as
251 * they are added to the server's I/O pending list. Two bits indicate
252 * if SQ, RQ, or both have I/O pending. The dto_lock is an irqsave
253 * spinlock that serializes access to the transport list with the RQ
254 * and SQ interrupt handlers.
256 static void dto_tasklet_func(unsigned long data)
258 struct svcxprt_rdma *xprt;
261 spin_lock_irqsave(&dto_lock, flags);
262 while (!list_empty(&dto_xprt_q)) {
263 xprt = list_entry(dto_xprt_q.next,
264 struct svcxprt_rdma, sc_dto_q);
265 list_del_init(&xprt->sc_dto_q);
266 spin_unlock_irqrestore(&dto_lock, flags);
271 svc_xprt_put(&xprt->sc_xprt);
272 spin_lock_irqsave(&dto_lock, flags);
274 spin_unlock_irqrestore(&dto_lock, flags);
278 * Receive Queue Completion Handler
280 * Since an RQ completion handler is called on interrupt context, we
281 * need to defer the handling of the I/O to a tasklet
283 static void rq_comp_handler(struct ib_cq *cq, void *cq_context)
285 struct svcxprt_rdma *xprt = cq_context;
288 /* Guard against unconditional flush call for destroyed QP */
289 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0)
293 * Set the bit regardless of whether or not it's on the list
294 * because it may be on the list already due to an SQ
297 set_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags);
300 * If this transport is not already on the DTO transport queue,
303 spin_lock_irqsave(&dto_lock, flags);
304 if (list_empty(&xprt->sc_dto_q)) {
305 svc_xprt_get(&xprt->sc_xprt);
306 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
308 spin_unlock_irqrestore(&dto_lock, flags);
310 /* Tasklet does all the work to avoid irqsave locks. */
311 tasklet_schedule(&dto_tasklet);
315 * rq_cq_reap - Process the RQ CQ.
317 * Take all completing WC off the CQE and enqueue the associated DTO
318 * context on the dto_q for the transport.
320 * Note that caller must hold a transport reference.
322 static void rq_cq_reap(struct svcxprt_rdma *xprt)
326 struct svc_rdma_op_ctxt *ctxt = NULL;
328 if (!test_and_clear_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags))
331 ib_req_notify_cq(xprt->sc_rq_cq, IB_CQ_NEXT_COMP);
332 atomic_inc(&rdma_stat_rq_poll);
334 while ((ret = ib_poll_cq(xprt->sc_rq_cq, 1, &wc)) > 0) {
335 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id;
336 ctxt->wc_status = wc.status;
337 ctxt->byte_len = wc.byte_len;
338 svc_rdma_unmap_dma(ctxt);
339 if (wc.status != IB_WC_SUCCESS) {
340 /* Close the transport */
341 dprintk("svcrdma: transport closing putting ctxt %p\n", ctxt);
342 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
343 svc_rdma_put_context(ctxt, 1);
344 svc_xprt_put(&xprt->sc_xprt);
347 spin_lock_bh(&xprt->sc_rq_dto_lock);
348 list_add_tail(&ctxt->dto_q, &xprt->sc_rq_dto_q);
349 spin_unlock_bh(&xprt->sc_rq_dto_lock);
350 svc_xprt_put(&xprt->sc_xprt);
354 atomic_inc(&rdma_stat_rq_prod);
356 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
358 * If data arrived before established event,
359 * don't enqueue. This defers RPC I/O until the
360 * RDMA connection is complete.
362 if (!test_bit(RDMAXPRT_CONN_PENDING, &xprt->sc_flags))
363 svc_xprt_enqueue(&xprt->sc_xprt);
367 * Send Queue Completion Handler - potentially called on interrupt context.
369 * Note that caller must hold a transport reference.
371 static void sq_cq_reap(struct svcxprt_rdma *xprt)
373 struct svc_rdma_op_ctxt *ctxt = NULL;
375 struct ib_cq *cq = xprt->sc_sq_cq;
379 if (!test_and_clear_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags))
382 ib_req_notify_cq(xprt->sc_sq_cq, IB_CQ_NEXT_COMP);
383 atomic_inc(&rdma_stat_sq_poll);
384 while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) {
385 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id;
388 svc_rdma_unmap_dma(ctxt);
389 if (wc.status != IB_WC_SUCCESS)
390 /* Close the transport */
391 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
393 /* Decrement used SQ WR count */
394 atomic_dec(&xprt->sc_sq_count);
395 wake_up(&xprt->sc_send_wait);
397 switch (ctxt->wr_op) {
399 svc_rdma_put_context(ctxt, 1);
402 case IB_WR_RDMA_WRITE:
403 svc_rdma_put_context(ctxt, 0);
406 case IB_WR_RDMA_READ:
407 if (test_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags)) {
408 struct svc_rdma_op_ctxt *read_hdr = ctxt->read_hdr;
410 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
411 spin_lock_bh(&xprt->sc_read_complete_lock);
412 list_add_tail(&read_hdr->dto_q,
413 &xprt->sc_read_complete_q);
414 spin_unlock_bh(&xprt->sc_read_complete_lock);
415 svc_xprt_enqueue(&xprt->sc_xprt);
417 svc_rdma_put_context(ctxt, 0);
421 printk(KERN_ERR "svcrdma: unexpected completion type, "
422 "opcode=%d, status=%d\n",
423 wc.opcode, wc.status);
426 svc_xprt_put(&xprt->sc_xprt);
430 atomic_inc(&rdma_stat_sq_prod);
433 static void sq_comp_handler(struct ib_cq *cq, void *cq_context)
435 struct svcxprt_rdma *xprt = cq_context;
438 /* Guard against unconditional flush call for destroyed QP */
439 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0)
443 * Set the bit regardless of whether or not it's on the list
444 * because it may be on the list already due to an RQ
447 set_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags);
450 * If this transport is not already on the DTO transport queue,
453 spin_lock_irqsave(&dto_lock, flags);
454 if (list_empty(&xprt->sc_dto_q)) {
455 svc_xprt_get(&xprt->sc_xprt);
456 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
458 spin_unlock_irqrestore(&dto_lock, flags);
460 /* Tasklet does all the work to avoid irqsave locks. */
461 tasklet_schedule(&dto_tasklet);
464 static void create_context_cache(struct svcxprt_rdma *xprt,
465 int ctxt_count, int ctxt_bump, int ctxt_max)
467 struct svc_rdma_op_ctxt *ctxt;
470 xprt->sc_ctxt_max = ctxt_max;
471 xprt->sc_ctxt_bump = ctxt_bump;
472 xprt->sc_ctxt_cnt = 0;
473 atomic_set(&xprt->sc_ctxt_used, 0);
475 INIT_LIST_HEAD(&xprt->sc_ctxt_free);
476 for (i = 0; i < ctxt_count; i++) {
477 ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL);
479 INIT_LIST_HEAD(&ctxt->free_list);
480 list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
486 static void destroy_context_cache(struct svcxprt_rdma *xprt)
488 while (!list_empty(&xprt->sc_ctxt_free)) {
489 struct svc_rdma_op_ctxt *ctxt;
490 ctxt = list_entry(xprt->sc_ctxt_free.next,
491 struct svc_rdma_op_ctxt,
493 list_del_init(&ctxt->free_list);
498 static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
501 struct svcxprt_rdma *cma_xprt = kzalloc(sizeof *cma_xprt, GFP_KERNEL);
505 svc_xprt_init(&svc_rdma_class, &cma_xprt->sc_xprt, serv);
506 INIT_LIST_HEAD(&cma_xprt->sc_accept_q);
507 INIT_LIST_HEAD(&cma_xprt->sc_dto_q);
508 INIT_LIST_HEAD(&cma_xprt->sc_rq_dto_q);
509 INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q);
510 init_waitqueue_head(&cma_xprt->sc_send_wait);
512 spin_lock_init(&cma_xprt->sc_lock);
513 spin_lock_init(&cma_xprt->sc_read_complete_lock);
514 spin_lock_init(&cma_xprt->sc_ctxt_lock);
515 spin_lock_init(&cma_xprt->sc_rq_dto_lock);
517 cma_xprt->sc_ord = svcrdma_ord;
519 cma_xprt->sc_max_req_size = svcrdma_max_req_size;
520 cma_xprt->sc_max_requests = svcrdma_max_requests;
521 cma_xprt->sc_sq_depth = svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT;
522 atomic_set(&cma_xprt->sc_sq_count, 0);
523 atomic_set(&cma_xprt->sc_ctxt_used, 0);
526 int reqs = cma_xprt->sc_max_requests;
527 create_context_cache(cma_xprt,
528 reqs << 1, /* starting size */
529 reqs, /* bump amount */
531 cma_xprt->sc_sq_depth +
532 RPCRDMA_MAX_THREADS + 1); /* max */
533 if (list_empty(&cma_xprt->sc_ctxt_free)) {
537 clear_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
539 set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
544 struct page *svc_rdma_get_page(void)
548 while ((page = alloc_page(GFP_KERNEL)) == NULL) {
549 /* If we can't get memory, wait a bit and try again */
550 printk(KERN_INFO "svcrdma: out of memory...retrying in 1000 "
552 schedule_timeout_uninterruptible(msecs_to_jiffies(1000));
557 int svc_rdma_post_recv(struct svcxprt_rdma *xprt)
559 struct ib_recv_wr recv_wr, *bad_recv_wr;
560 struct svc_rdma_op_ctxt *ctxt;
567 ctxt = svc_rdma_get_context(xprt);
569 ctxt->direction = DMA_FROM_DEVICE;
570 for (sge_no = 0; buflen < xprt->sc_max_req_size; sge_no++) {
571 BUG_ON(sge_no >= xprt->sc_max_sge);
572 page = svc_rdma_get_page();
573 ctxt->pages[sge_no] = page;
574 atomic_inc(&xprt->sc_dma_used);
575 pa = ib_dma_map_page(xprt->sc_cm_id->device,
578 ctxt->sge[sge_no].addr = pa;
579 ctxt->sge[sge_no].length = PAGE_SIZE;
580 ctxt->sge[sge_no].lkey = xprt->sc_phys_mr->lkey;
583 ctxt->count = sge_no;
585 recv_wr.sg_list = &ctxt->sge[0];
586 recv_wr.num_sge = ctxt->count;
587 recv_wr.wr_id = (u64)(unsigned long)ctxt;
589 svc_xprt_get(&xprt->sc_xprt);
590 ret = ib_post_recv(xprt->sc_qp, &recv_wr, &bad_recv_wr);
592 svc_xprt_put(&xprt->sc_xprt);
593 svc_rdma_put_context(ctxt, 1);
599 * This function handles the CONNECT_REQUEST event on a listening
600 * endpoint. It is passed the cma_id for the _new_ connection. The context in
601 * this cma_id is inherited from the listening cma_id and is the svc_xprt
602 * structure for the listening endpoint.
604 * This function creates a new xprt for the new connection and enqueues it on
605 * the accept queue for the listent xprt. When the listen thread is kicked, it
606 * will call the recvfrom method on the listen xprt which will accept the new
609 static void handle_connect_req(struct rdma_cm_id *new_cma_id)
611 struct svcxprt_rdma *listen_xprt = new_cma_id->context;
612 struct svcxprt_rdma *newxprt;
615 /* Create a new transport */
616 newxprt = rdma_create_xprt(listen_xprt->sc_xprt.xpt_server, 0);
618 dprintk("svcrdma: failed to create new transport\n");
621 newxprt->sc_cm_id = new_cma_id;
622 new_cma_id->context = newxprt;
623 dprintk("svcrdma: Creating newxprt=%p, cm_id=%p, listenxprt=%p\n",
624 newxprt, newxprt->sc_cm_id, listen_xprt);
626 /* Set the local and remote addresses in the transport */
627 sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr;
628 svc_xprt_set_remote(&newxprt->sc_xprt, sa, svc_addr_len(sa));
629 sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr;
630 svc_xprt_set_local(&newxprt->sc_xprt, sa, svc_addr_len(sa));
633 * Enqueue the new transport on the accept queue of the listening
636 spin_lock_bh(&listen_xprt->sc_lock);
637 list_add_tail(&newxprt->sc_accept_q, &listen_xprt->sc_accept_q);
638 spin_unlock_bh(&listen_xprt->sc_lock);
641 * Can't use svc_xprt_received here because we are not on a
644 set_bit(XPT_CONN, &listen_xprt->sc_xprt.xpt_flags);
645 svc_xprt_enqueue(&listen_xprt->sc_xprt);
649 * Handles events generated on the listening endpoint. These events will be
650 * either be incoming connect requests or adapter removal events.
652 static int rdma_listen_handler(struct rdma_cm_id *cma_id,
653 struct rdma_cm_event *event)
655 struct svcxprt_rdma *xprt = cma_id->context;
658 switch (event->event) {
659 case RDMA_CM_EVENT_CONNECT_REQUEST:
660 dprintk("svcrdma: Connect request on cma_id=%p, xprt = %p, "
661 "event=%d\n", cma_id, cma_id->context, event->event);
662 handle_connect_req(cma_id);
665 case RDMA_CM_EVENT_ESTABLISHED:
666 /* Accept complete */
667 dprintk("svcrdma: Connection completed on LISTEN xprt=%p, "
668 "cm_id=%p\n", xprt, cma_id);
671 case RDMA_CM_EVENT_DEVICE_REMOVAL:
672 dprintk("svcrdma: Device removal xprt=%p, cm_id=%p\n",
675 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
679 dprintk("svcrdma: Unexpected event on listening endpoint %p, "
680 "event=%d\n", cma_id, event->event);
687 static int rdma_cma_handler(struct rdma_cm_id *cma_id,
688 struct rdma_cm_event *event)
690 struct svc_xprt *xprt = cma_id->context;
691 struct svcxprt_rdma *rdma =
692 container_of(xprt, struct svcxprt_rdma, sc_xprt);
693 switch (event->event) {
694 case RDMA_CM_EVENT_ESTABLISHED:
695 /* Accept complete */
697 dprintk("svcrdma: Connection completed on DTO xprt=%p, "
698 "cm_id=%p\n", xprt, cma_id);
699 clear_bit(RDMAXPRT_CONN_PENDING, &rdma->sc_flags);
700 svc_xprt_enqueue(xprt);
702 case RDMA_CM_EVENT_DISCONNECTED:
703 dprintk("svcrdma: Disconnect on DTO xprt=%p, cm_id=%p\n",
706 set_bit(XPT_CLOSE, &xprt->xpt_flags);
707 svc_xprt_enqueue(xprt);
711 case RDMA_CM_EVENT_DEVICE_REMOVAL:
712 dprintk("svcrdma: Device removal cma_id=%p, xprt = %p, "
713 "event=%d\n", cma_id, xprt, event->event);
715 set_bit(XPT_CLOSE, &xprt->xpt_flags);
716 svc_xprt_enqueue(xprt);
720 dprintk("svcrdma: Unexpected event on DTO endpoint %p, "
721 "event=%d\n", cma_id, event->event);
728 * Create a listening RDMA service endpoint.
730 static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
731 struct sockaddr *sa, int salen,
734 struct rdma_cm_id *listen_id;
735 struct svcxprt_rdma *cma_xprt;
736 struct svc_xprt *xprt;
739 dprintk("svcrdma: Creating RDMA socket\n");
741 cma_xprt = rdma_create_xprt(serv, 1);
743 return ERR_PTR(-ENOMEM);
744 xprt = &cma_xprt->sc_xprt;
746 listen_id = rdma_create_id(rdma_listen_handler, cma_xprt, RDMA_PS_TCP);
747 if (IS_ERR(listen_id)) {
748 ret = PTR_ERR(listen_id);
749 dprintk("svcrdma: rdma_create_id failed = %d\n", ret);
753 ret = rdma_bind_addr(listen_id, sa);
755 dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret);
758 cma_xprt->sc_cm_id = listen_id;
760 ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG);
762 dprintk("svcrdma: rdma_listen failed = %d\n", ret);
767 * We need to use the address from the cm_id in case the
768 * caller specified 0 for the port number.
770 sa = (struct sockaddr *)&cma_xprt->sc_cm_id->route.addr.src_addr;
771 svc_xprt_set_local(&cma_xprt->sc_xprt, sa, salen);
773 return &cma_xprt->sc_xprt;
776 rdma_destroy_id(listen_id);
783 * This is the xpo_recvfrom function for listening endpoints. Its
784 * purpose is to accept incoming connections. The CMA callback handler
785 * has already created a new transport and attached it to the new CMA
788 * There is a queue of pending connections hung on the listening
789 * transport. This queue contains the new svc_xprt structure. This
790 * function takes svc_xprt structures off the accept_q and completes
793 static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
795 struct svcxprt_rdma *listen_rdma;
796 struct svcxprt_rdma *newxprt = NULL;
797 struct rdma_conn_param conn_param;
798 struct ib_qp_init_attr qp_attr;
799 struct ib_device_attr devattr;
803 listen_rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt);
804 clear_bit(XPT_CONN, &xprt->xpt_flags);
805 /* Get the next entry off the accept list */
806 spin_lock_bh(&listen_rdma->sc_lock);
807 if (!list_empty(&listen_rdma->sc_accept_q)) {
808 newxprt = list_entry(listen_rdma->sc_accept_q.next,
809 struct svcxprt_rdma, sc_accept_q);
810 list_del_init(&newxprt->sc_accept_q);
812 if (!list_empty(&listen_rdma->sc_accept_q))
813 set_bit(XPT_CONN, &listen_rdma->sc_xprt.xpt_flags);
814 spin_unlock_bh(&listen_rdma->sc_lock);
818 dprintk("svcrdma: newxprt from accept queue = %p, cm_id=%p\n",
819 newxprt, newxprt->sc_cm_id);
821 ret = ib_query_device(newxprt->sc_cm_id->device, &devattr);
823 dprintk("svcrdma: could not query device attributes on "
824 "device %p, rc=%d\n", newxprt->sc_cm_id->device, ret);
828 /* Qualify the transport resource defaults with the
829 * capabilities of this particular device */
830 newxprt->sc_max_sge = min((size_t)devattr.max_sge,
831 (size_t)RPCSVC_MAXPAGES);
832 newxprt->sc_max_requests = min((size_t)devattr.max_qp_wr,
833 (size_t)svcrdma_max_requests);
834 newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests;
836 newxprt->sc_ord = min((size_t)devattr.max_qp_rd_atom,
837 (size_t)svcrdma_ord);
839 newxprt->sc_pd = ib_alloc_pd(newxprt->sc_cm_id->device);
840 if (IS_ERR(newxprt->sc_pd)) {
841 dprintk("svcrdma: error creating PD for connect request\n");
844 newxprt->sc_sq_cq = ib_create_cq(newxprt->sc_cm_id->device,
848 newxprt->sc_sq_depth,
850 if (IS_ERR(newxprt->sc_sq_cq)) {
851 dprintk("svcrdma: error creating SQ CQ for connect request\n");
854 newxprt->sc_rq_cq = ib_create_cq(newxprt->sc_cm_id->device,
858 newxprt->sc_max_requests,
860 if (IS_ERR(newxprt->sc_rq_cq)) {
861 dprintk("svcrdma: error creating RQ CQ for connect request\n");
865 memset(&qp_attr, 0, sizeof qp_attr);
866 qp_attr.event_handler = qp_event_handler;
867 qp_attr.qp_context = &newxprt->sc_xprt;
868 qp_attr.cap.max_send_wr = newxprt->sc_sq_depth;
869 qp_attr.cap.max_recv_wr = newxprt->sc_max_requests;
870 qp_attr.cap.max_send_sge = newxprt->sc_max_sge;
871 qp_attr.cap.max_recv_sge = newxprt->sc_max_sge;
872 qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
873 qp_attr.qp_type = IB_QPT_RC;
874 qp_attr.send_cq = newxprt->sc_sq_cq;
875 qp_attr.recv_cq = newxprt->sc_rq_cq;
876 dprintk("svcrdma: newxprt->sc_cm_id=%p, newxprt->sc_pd=%p\n"
877 " cm_id->device=%p, sc_pd->device=%p\n"
878 " cap.max_send_wr = %d\n"
879 " cap.max_recv_wr = %d\n"
880 " cap.max_send_sge = %d\n"
881 " cap.max_recv_sge = %d\n",
882 newxprt->sc_cm_id, newxprt->sc_pd,
883 newxprt->sc_cm_id->device, newxprt->sc_pd->device,
884 qp_attr.cap.max_send_wr,
885 qp_attr.cap.max_recv_wr,
886 qp_attr.cap.max_send_sge,
887 qp_attr.cap.max_recv_sge);
889 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr);
892 * XXX: This is a hack. We need a xx_request_qp interface
893 * that will adjust the qp_attr's with a best-effort
896 qp_attr.cap.max_send_sge -= 2;
897 qp_attr.cap.max_recv_sge -= 2;
898 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd,
901 dprintk("svcrdma: failed to create QP, ret=%d\n", ret);
904 newxprt->sc_max_sge = qp_attr.cap.max_send_sge;
905 newxprt->sc_max_sge = qp_attr.cap.max_recv_sge;
906 newxprt->sc_sq_depth = qp_attr.cap.max_send_wr;
907 newxprt->sc_max_requests = qp_attr.cap.max_recv_wr;
909 newxprt->sc_qp = newxprt->sc_cm_id->qp;
911 /* Register all of physical memory */
912 newxprt->sc_phys_mr = ib_get_dma_mr(newxprt->sc_pd,
913 IB_ACCESS_LOCAL_WRITE |
914 IB_ACCESS_REMOTE_WRITE);
915 if (IS_ERR(newxprt->sc_phys_mr)) {
916 dprintk("svcrdma: Failed to create DMA MR ret=%d\n", ret);
920 /* Post receive buffers */
921 for (i = 0; i < newxprt->sc_max_requests; i++) {
922 ret = svc_rdma_post_recv(newxprt);
924 dprintk("svcrdma: failure posting receive buffers\n");
929 /* Swap out the handler */
930 newxprt->sc_cm_id->event_handler = rdma_cma_handler;
933 * Arm the CQs for the SQ and RQ before accepting so we can't
934 * miss the first message
936 ib_req_notify_cq(newxprt->sc_sq_cq, IB_CQ_NEXT_COMP);
937 ib_req_notify_cq(newxprt->sc_rq_cq, IB_CQ_NEXT_COMP);
939 /* Accept Connection */
940 set_bit(RDMAXPRT_CONN_PENDING, &newxprt->sc_flags);
941 memset(&conn_param, 0, sizeof conn_param);
942 conn_param.responder_resources = 0;
943 conn_param.initiator_depth = newxprt->sc_ord;
944 ret = rdma_accept(newxprt->sc_cm_id, &conn_param);
946 dprintk("svcrdma: failed to accept new connection, ret=%d\n",
951 dprintk("svcrdma: new connection %p accepted with the following "
953 " local_ip : %d.%d.%d.%d\n"
955 " remote_ip : %d.%d.%d.%d\n"
956 " remote_port : %d\n"
959 " max_requests : %d\n"
962 NIPQUAD(((struct sockaddr_in *)&newxprt->sc_cm_id->
963 route.addr.src_addr)->sin_addr.s_addr),
964 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id->
965 route.addr.src_addr)->sin_port),
966 NIPQUAD(((struct sockaddr_in *)&newxprt->sc_cm_id->
967 route.addr.dst_addr)->sin_addr.s_addr),
968 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id->
969 route.addr.dst_addr)->sin_port),
971 newxprt->sc_sq_depth,
972 newxprt->sc_max_requests,
975 return &newxprt->sc_xprt;
978 dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret);
979 /* Take a reference in case the DTO handler runs */
980 svc_xprt_get(&newxprt->sc_xprt);
981 if (newxprt->sc_qp && !IS_ERR(newxprt->sc_qp))
982 ib_destroy_qp(newxprt->sc_qp);
983 rdma_destroy_id(newxprt->sc_cm_id);
984 /* This call to put will destroy the transport */
985 svc_xprt_put(&newxprt->sc_xprt);
989 static void svc_rdma_release_rqst(struct svc_rqst *rqstp)
994 * When connected, an svc_xprt has at least two references:
996 * - A reference held by the cm_id between the ESTABLISHED and
997 * DISCONNECTED events. If the remote peer disconnected first, this
998 * reference could be gone.
1000 * - A reference held by the svc_recv code that called this function
1001 * as part of close processing.
1003 * At a minimum one references should still be held.
1005 static void svc_rdma_detach(struct svc_xprt *xprt)
1007 struct svcxprt_rdma *rdma =
1008 container_of(xprt, struct svcxprt_rdma, sc_xprt);
1009 dprintk("svc: svc_rdma_detach(%p)\n", xprt);
1011 /* Disconnect and flush posted WQE */
1012 rdma_disconnect(rdma->sc_cm_id);
1015 static void __svc_rdma_free(struct work_struct *work)
1017 struct svcxprt_rdma *rdma =
1018 container_of(work, struct svcxprt_rdma, sc_work);
1019 dprintk("svcrdma: svc_rdma_free(%p)\n", rdma);
1021 /* We should only be called from kref_put */
1022 BUG_ON(atomic_read(&rdma->sc_xprt.xpt_ref.refcount) != 0);
1025 * Destroy queued, but not processed read completions. Note
1026 * that this cleanup has to be done before destroying the
1027 * cm_id because the device ptr is needed to unmap the dma in
1028 * svc_rdma_put_context.
1030 while (!list_empty(&rdma->sc_read_complete_q)) {
1031 struct svc_rdma_op_ctxt *ctxt;
1032 ctxt = list_entry(rdma->sc_read_complete_q.next,
1033 struct svc_rdma_op_ctxt,
1035 list_del_init(&ctxt->dto_q);
1036 svc_rdma_put_context(ctxt, 1);
1039 /* Destroy queued, but not processed recv completions */
1040 while (!list_empty(&rdma->sc_rq_dto_q)) {
1041 struct svc_rdma_op_ctxt *ctxt;
1042 ctxt = list_entry(rdma->sc_rq_dto_q.next,
1043 struct svc_rdma_op_ctxt,
1045 list_del_init(&ctxt->dto_q);
1046 svc_rdma_put_context(ctxt, 1);
1049 /* Warn if we leaked a resource or under-referenced */
1050 WARN_ON(atomic_read(&rdma->sc_ctxt_used) != 0);
1051 WARN_ON(atomic_read(&rdma->sc_dma_used) != 0);
1053 /* Destroy the QP if present (not a listener) */
1054 if (rdma->sc_qp && !IS_ERR(rdma->sc_qp))
1055 ib_destroy_qp(rdma->sc_qp);
1057 if (rdma->sc_sq_cq && !IS_ERR(rdma->sc_sq_cq))
1058 ib_destroy_cq(rdma->sc_sq_cq);
1060 if (rdma->sc_rq_cq && !IS_ERR(rdma->sc_rq_cq))
1061 ib_destroy_cq(rdma->sc_rq_cq);
1063 if (rdma->sc_phys_mr && !IS_ERR(rdma->sc_phys_mr))
1064 ib_dereg_mr(rdma->sc_phys_mr);
1066 if (rdma->sc_pd && !IS_ERR(rdma->sc_pd))
1067 ib_dealloc_pd(rdma->sc_pd);
1069 /* Destroy the CM ID */
1070 rdma_destroy_id(rdma->sc_cm_id);
1072 destroy_context_cache(rdma);
1076 static void svc_rdma_free(struct svc_xprt *xprt)
1078 struct svcxprt_rdma *rdma =
1079 container_of(xprt, struct svcxprt_rdma, sc_xprt);
1080 INIT_WORK(&rdma->sc_work, __svc_rdma_free);
1081 schedule_work(&rdma->sc_work);
1084 static int svc_rdma_has_wspace(struct svc_xprt *xprt)
1086 struct svcxprt_rdma *rdma =
1087 container_of(xprt, struct svcxprt_rdma, sc_xprt);
1090 * If there are fewer SQ WR available than required to send a
1091 * simple response, return false.
1093 if ((rdma->sc_sq_depth - atomic_read(&rdma->sc_sq_count) < 3))
1097 * ...or there are already waiters on the SQ,
1100 if (waitqueue_active(&rdma->sc_send_wait))
1103 /* Otherwise return true. */
1107 int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr)
1109 struct ib_send_wr *bad_wr;
1112 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
1115 BUG_ON(wr->send_flags != IB_SEND_SIGNALED);
1116 BUG_ON(((struct svc_rdma_op_ctxt *)(unsigned long)wr->wr_id)->wr_op !=
1118 /* If the SQ is full, wait until an SQ entry is available */
1120 spin_lock_bh(&xprt->sc_lock);
1121 if (xprt->sc_sq_depth == atomic_read(&xprt->sc_sq_count)) {
1122 spin_unlock_bh(&xprt->sc_lock);
1123 atomic_inc(&rdma_stat_sq_starve);
1125 /* See if we can opportunistically reap SQ WR to make room */
1128 /* Wait until SQ WR available if SQ still full */
1129 wait_event(xprt->sc_send_wait,
1130 atomic_read(&xprt->sc_sq_count) <
1132 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
1136 /* Bumped used SQ WR count and post */
1137 svc_xprt_get(&xprt->sc_xprt);
1138 ret = ib_post_send(xprt->sc_qp, wr, &bad_wr);
1140 atomic_inc(&xprt->sc_sq_count);
1142 svc_xprt_put(&xprt->sc_xprt);
1143 dprintk("svcrdma: failed to post SQ WR rc=%d, "
1144 "sc_sq_count=%d, sc_sq_depth=%d\n",
1145 ret, atomic_read(&xprt->sc_sq_count),
1148 spin_unlock_bh(&xprt->sc_lock);
1154 void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp,
1155 enum rpcrdma_errcode err)
1157 struct ib_send_wr err_wr;
1160 struct svc_rdma_op_ctxt *ctxt;
1165 p = svc_rdma_get_page();
1166 va = page_address(p);
1168 /* XDR encode error */
1169 length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va);
1171 /* Prepare SGE for local address */
1172 atomic_inc(&xprt->sc_dma_used);
1173 sge.addr = ib_dma_map_page(xprt->sc_cm_id->device,
1174 p, 0, PAGE_SIZE, DMA_FROM_DEVICE);
1175 sge.lkey = xprt->sc_phys_mr->lkey;
1176 sge.length = length;
1178 ctxt = svc_rdma_get_context(xprt);
1182 /* Prepare SEND WR */
1183 memset(&err_wr, 0, sizeof err_wr);
1184 ctxt->wr_op = IB_WR_SEND;
1185 err_wr.wr_id = (unsigned long)ctxt;
1186 err_wr.sg_list = &sge;
1188 err_wr.opcode = IB_WR_SEND;
1189 err_wr.send_flags = IB_SEND_SIGNALED;
1192 ret = svc_rdma_send(xprt, &err_wr);
1194 dprintk("svcrdma: Error %d posting send for protocol error\n",
1196 svc_rdma_put_context(ctxt, 1);