net: Make static
[linux-2.6.git] / net / sunrpc / xprtrdma / svc_rdma_sendto.c
1 /*
2  * Copyright (c) 2005-2006 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/debug.h>
43 #include <linux/sunrpc/rpc_rdma.h>
44 #include <linux/spinlock.h>
45 #include <asm/unaligned.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
52 /* Encode an XDR as an array of IB SGE
53  *
54  * Assumptions:
55  * - head[0] is physically contiguous.
56  * - tail[0] is physically contiguous.
57  * - pages[] is not physically or virtually contigous and consists of
58  *   PAGE_SIZE elements.
59  *
60  * Output:
61  * SGE[0]              reserved for RCPRDMA header
62  * SGE[1]              data from xdr->head[]
63  * SGE[2..sge_count-2] data from xdr->pages[]
64  * SGE[sge_count-1]    data from xdr->tail.
65  *
66  * The max SGE we need is the length of the XDR / pagesize + one for
67  * head + one for tail + one for RPCRDMA header. Since RPCSVC_MAXPAGES
68  * reserves a page for both the request and the reply header, and this
69  * array is only concerned with the reply we are assured that we have
70  * on extra page for the RPCRMDA header.
71  */
72 static int fast_reg_xdr(struct svcxprt_rdma *xprt,
73                  struct xdr_buf *xdr,
74                  struct svc_rdma_req_map *vec)
75 {
76         int sge_no;
77         u32 sge_bytes;
78         u32 page_bytes;
79         u32 page_off;
80         int page_no = 0;
81         u8 *frva;
82         struct svc_rdma_fastreg_mr *frmr;
83
84         frmr = svc_rdma_get_frmr(xprt);
85         if (IS_ERR(frmr))
86                 return -ENOMEM;
87         vec->frmr = frmr;
88
89         /* Skip the RPCRDMA header */
90         sge_no = 1;
91
92         /* Map the head. */
93         frva = (void *)((unsigned long)(xdr->head[0].iov_base) & PAGE_MASK);
94         vec->sge[sge_no].iov_base = xdr->head[0].iov_base;
95         vec->sge[sge_no].iov_len = xdr->head[0].iov_len;
96         vec->count = 2;
97         sge_no++;
98
99         /* Build the FRMR */
100         frmr->kva = frva;
101         frmr->direction = DMA_TO_DEVICE;
102         frmr->access_flags = 0;
103         frmr->map_len = PAGE_SIZE;
104         frmr->page_list_len = 1;
105         frmr->page_list->page_list[page_no] =
106                 ib_dma_map_single(xprt->sc_cm_id->device,
107                                   (void *)xdr->head[0].iov_base,
108                                   PAGE_SIZE, DMA_TO_DEVICE);
109         if (ib_dma_mapping_error(xprt->sc_cm_id->device,
110                                  frmr->page_list->page_list[page_no]))
111                 goto fatal_err;
112         atomic_inc(&xprt->sc_dma_used);
113
114         page_off = xdr->page_base;
115         page_bytes = xdr->page_len + page_off;
116         if (!page_bytes)
117                 goto encode_tail;
118
119         /* Map the pages */
120         vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off;
121         vec->sge[sge_no].iov_len = page_bytes;
122         sge_no++;
123         while (page_bytes) {
124                 struct page *page;
125
126                 page = xdr->pages[page_no++];
127                 sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off));
128                 page_bytes -= sge_bytes;
129
130                 frmr->page_list->page_list[page_no] =
131                         ib_dma_map_page(xprt->sc_cm_id->device, page, 0,
132                                           PAGE_SIZE, DMA_TO_DEVICE);
133                 if (ib_dma_mapping_error(xprt->sc_cm_id->device,
134                                          frmr->page_list->page_list[page_no]))
135                         goto fatal_err;
136
137                 atomic_inc(&xprt->sc_dma_used);
138                 page_off = 0; /* reset for next time through loop */
139                 frmr->map_len += PAGE_SIZE;
140                 frmr->page_list_len++;
141         }
142         vec->count++;
143
144  encode_tail:
145         /* Map tail */
146         if (0 == xdr->tail[0].iov_len)
147                 goto done;
148
149         vec->count++;
150         vec->sge[sge_no].iov_len = xdr->tail[0].iov_len;
151
152         if (((unsigned long)xdr->tail[0].iov_base & PAGE_MASK) ==
153             ((unsigned long)xdr->head[0].iov_base & PAGE_MASK)) {
154                 /*
155                  * If head and tail use the same page, we don't need
156                  * to map it again.
157                  */
158                 vec->sge[sge_no].iov_base = xdr->tail[0].iov_base;
159         } else {
160                 void *va;
161
162                 /* Map another page for the tail */
163                 page_off = (unsigned long)xdr->tail[0].iov_base & ~PAGE_MASK;
164                 va = (void *)((unsigned long)xdr->tail[0].iov_base & PAGE_MASK);
165                 vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off;
166
167                 frmr->page_list->page_list[page_no] =
168                         ib_dma_map_single(xprt->sc_cm_id->device, va, PAGE_SIZE,
169                                           DMA_TO_DEVICE);
170                 if (ib_dma_mapping_error(xprt->sc_cm_id->device,
171                                          frmr->page_list->page_list[page_no]))
172                         goto fatal_err;
173                 atomic_inc(&xprt->sc_dma_used);
174                 frmr->map_len += PAGE_SIZE;
175                 frmr->page_list_len++;
176         }
177
178  done:
179         if (svc_rdma_fastreg(xprt, frmr))
180                 goto fatal_err;
181
182         return 0;
183
184  fatal_err:
185         printk("svcrdma: Error fast registering memory for xprt %p\n", xprt);
186         svc_rdma_put_frmr(xprt, frmr);
187         return -EIO;
188 }
189
190 static int map_xdr(struct svcxprt_rdma *xprt,
191                    struct xdr_buf *xdr,
192                    struct svc_rdma_req_map *vec)
193 {
194         int sge_max = (xdr->len+PAGE_SIZE-1) / PAGE_SIZE + 3;
195         int sge_no;
196         u32 sge_bytes;
197         u32 page_bytes;
198         u32 page_off;
199         int page_no;
200
201         BUG_ON(xdr->len !=
202                (xdr->head[0].iov_len + xdr->page_len + xdr->tail[0].iov_len));
203
204         if (xprt->sc_frmr_pg_list_len)
205                 return fast_reg_xdr(xprt, xdr, vec);
206
207         /* Skip the first sge, this is for the RPCRDMA header */
208         sge_no = 1;
209
210         /* Head SGE */
211         vec->sge[sge_no].iov_base = xdr->head[0].iov_base;
212         vec->sge[sge_no].iov_len = xdr->head[0].iov_len;
213         sge_no++;
214
215         /* pages SGE */
216         page_no = 0;
217         page_bytes = xdr->page_len;
218         page_off = xdr->page_base;
219         while (page_bytes) {
220                 vec->sge[sge_no].iov_base =
221                         page_address(xdr->pages[page_no]) + page_off;
222                 sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off));
223                 page_bytes -= sge_bytes;
224                 vec->sge[sge_no].iov_len = sge_bytes;
225
226                 sge_no++;
227                 page_no++;
228                 page_off = 0; /* reset for next time through loop */
229         }
230
231         /* Tail SGE */
232         if (xdr->tail[0].iov_len) {
233                 vec->sge[sge_no].iov_base = xdr->tail[0].iov_base;
234                 vec->sge[sge_no].iov_len = xdr->tail[0].iov_len;
235                 sge_no++;
236         }
237
238         BUG_ON(sge_no > sge_max);
239         vec->count = sge_no;
240         return 0;
241 }
242
243 /* Assumptions:
244  * - We are using FRMR
245  *     - or -
246  * - The specified write_len can be represented in sc_max_sge * PAGE_SIZE
247  */
248 static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp,
249                       u32 rmr, u64 to,
250                       u32 xdr_off, int write_len,
251                       struct svc_rdma_req_map *vec)
252 {
253         struct ib_send_wr write_wr;
254         struct ib_sge *sge;
255         int xdr_sge_no;
256         int sge_no;
257         int sge_bytes;
258         int sge_off;
259         int bc;
260         struct svc_rdma_op_ctxt *ctxt;
261
262         BUG_ON(vec->count > RPCSVC_MAXPAGES);
263         dprintk("svcrdma: RDMA_WRITE rmr=%x, to=%llx, xdr_off=%d, "
264                 "write_len=%d, vec->sge=%p, vec->count=%lu\n",
265                 rmr, (unsigned long long)to, xdr_off,
266                 write_len, vec->sge, vec->count);
267
268         ctxt = svc_rdma_get_context(xprt);
269         ctxt->direction = DMA_TO_DEVICE;
270         sge = ctxt->sge;
271
272         /* Find the SGE associated with xdr_off */
273         for (bc = xdr_off, xdr_sge_no = 1; bc && xdr_sge_no < vec->count;
274              xdr_sge_no++) {
275                 if (vec->sge[xdr_sge_no].iov_len > bc)
276                         break;
277                 bc -= vec->sge[xdr_sge_no].iov_len;
278         }
279
280         sge_off = bc;
281         bc = write_len;
282         sge_no = 0;
283
284         /* Copy the remaining SGE */
285         while (bc != 0) {
286                 sge_bytes = min_t(size_t,
287                           bc, vec->sge[xdr_sge_no].iov_len-sge_off);
288                 sge[sge_no].length = sge_bytes;
289                 if (!vec->frmr) {
290                         sge[sge_no].addr =
291                                 ib_dma_map_single(xprt->sc_cm_id->device,
292                                                   (void *)
293                                                   vec->sge[xdr_sge_no].iov_base + sge_off,
294                                                   sge_bytes, DMA_TO_DEVICE);
295                         if (ib_dma_mapping_error(xprt->sc_cm_id->device,
296                                                  sge[sge_no].addr))
297                                 goto err;
298                         atomic_inc(&xprt->sc_dma_used);
299                         sge[sge_no].lkey = xprt->sc_dma_lkey;
300                 } else {
301                         sge[sge_no].addr = (unsigned long)
302                                 vec->sge[xdr_sge_no].iov_base + sge_off;
303                         sge[sge_no].lkey = vec->frmr->mr->lkey;
304                 }
305                 ctxt->count++;
306                 ctxt->frmr = vec->frmr;
307                 sge_off = 0;
308                 sge_no++;
309                 xdr_sge_no++;
310                 BUG_ON(xdr_sge_no > vec->count);
311                 bc -= sge_bytes;
312         }
313
314         /* Prepare WRITE WR */
315         memset(&write_wr, 0, sizeof write_wr);
316         ctxt->wr_op = IB_WR_RDMA_WRITE;
317         write_wr.wr_id = (unsigned long)ctxt;
318         write_wr.sg_list = &sge[0];
319         write_wr.num_sge = sge_no;
320         write_wr.opcode = IB_WR_RDMA_WRITE;
321         write_wr.send_flags = IB_SEND_SIGNALED;
322         write_wr.wr.rdma.rkey = rmr;
323         write_wr.wr.rdma.remote_addr = to;
324
325         /* Post It */
326         atomic_inc(&rdma_stat_write);
327         if (svc_rdma_send(xprt, &write_wr))
328                 goto err;
329         return 0;
330  err:
331         svc_rdma_put_context(ctxt, 0);
332         /* Fatal error, close transport */
333         return -EIO;
334 }
335
336 static int send_write_chunks(struct svcxprt_rdma *xprt,
337                              struct rpcrdma_msg *rdma_argp,
338                              struct rpcrdma_msg *rdma_resp,
339                              struct svc_rqst *rqstp,
340                              struct svc_rdma_req_map *vec)
341 {
342         u32 xfer_len = rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len;
343         int write_len;
344         int max_write;
345         u32 xdr_off;
346         int chunk_off;
347         int chunk_no;
348         struct rpcrdma_write_array *arg_ary;
349         struct rpcrdma_write_array *res_ary;
350         int ret;
351
352         arg_ary = svc_rdma_get_write_array(rdma_argp);
353         if (!arg_ary)
354                 return 0;
355         res_ary = (struct rpcrdma_write_array *)
356                 &rdma_resp->rm_body.rm_chunks[1];
357
358         if (vec->frmr)
359                 max_write = vec->frmr->map_len;
360         else
361                 max_write = xprt->sc_max_sge * PAGE_SIZE;
362
363         /* Write chunks start at the pagelist */
364         for (xdr_off = rqstp->rq_res.head[0].iov_len, chunk_no = 0;
365              xfer_len && chunk_no < arg_ary->wc_nchunks;
366              chunk_no++) {
367                 struct rpcrdma_segment *arg_ch;
368                 u64 rs_offset;
369
370                 arg_ch = &arg_ary->wc_array[chunk_no].wc_target;
371                 write_len = min(xfer_len, arg_ch->rs_length);
372
373                 /* Prepare the response chunk given the length actually
374                  * written */
375                 rs_offset = get_unaligned(&(arg_ch->rs_offset));
376                 svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no,
377                                             arg_ch->rs_handle,
378                                             rs_offset,
379                                             write_len);
380                 chunk_off = 0;
381                 while (write_len) {
382                         int this_write;
383                         this_write = min(write_len, max_write);
384                         ret = send_write(xprt, rqstp,
385                                          arg_ch->rs_handle,
386                                          rs_offset + chunk_off,
387                                          xdr_off,
388                                          this_write,
389                                          vec);
390                         if (ret) {
391                                 dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n",
392                                         ret);
393                                 return -EIO;
394                         }
395                         chunk_off += this_write;
396                         xdr_off += this_write;
397                         xfer_len -= this_write;
398                         write_len -= this_write;
399                 }
400         }
401         /* Update the req with the number of chunks actually used */
402         svc_rdma_xdr_encode_write_list(rdma_resp, chunk_no);
403
404         return rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len;
405 }
406
407 static int send_reply_chunks(struct svcxprt_rdma *xprt,
408                              struct rpcrdma_msg *rdma_argp,
409                              struct rpcrdma_msg *rdma_resp,
410                              struct svc_rqst *rqstp,
411                              struct svc_rdma_req_map *vec)
412 {
413         u32 xfer_len = rqstp->rq_res.len;
414         int write_len;
415         int max_write;
416         u32 xdr_off;
417         int chunk_no;
418         int chunk_off;
419         struct rpcrdma_segment *ch;
420         struct rpcrdma_write_array *arg_ary;
421         struct rpcrdma_write_array *res_ary;
422         int ret;
423
424         arg_ary = svc_rdma_get_reply_array(rdma_argp);
425         if (!arg_ary)
426                 return 0;
427         /* XXX: need to fix when reply lists occur with read-list and or
428          * write-list */
429         res_ary = (struct rpcrdma_write_array *)
430                 &rdma_resp->rm_body.rm_chunks[2];
431
432         if (vec->frmr)
433                 max_write = vec->frmr->map_len;
434         else
435                 max_write = xprt->sc_max_sge * PAGE_SIZE;
436
437         /* xdr offset starts at RPC message */
438         for (xdr_off = 0, chunk_no = 0;
439              xfer_len && chunk_no < arg_ary->wc_nchunks;
440              chunk_no++) {
441                 u64 rs_offset;
442                 ch = &arg_ary->wc_array[chunk_no].wc_target;
443                 write_len = min(xfer_len, ch->rs_length);
444
445                 /* Prepare the reply chunk given the length actually
446                  * written */
447                 rs_offset = get_unaligned(&(ch->rs_offset));
448                 svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no,
449                                             ch->rs_handle, rs_offset,
450                                             write_len);
451                 chunk_off = 0;
452                 while (write_len) {
453                         int this_write;
454
455                         this_write = min(write_len, max_write);
456                         ret = send_write(xprt, rqstp,
457                                          ch->rs_handle,
458                                          rs_offset + chunk_off,
459                                          xdr_off,
460                                          this_write,
461                                          vec);
462                         if (ret) {
463                                 dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n",
464                                         ret);
465                                 return -EIO;
466                         }
467                         chunk_off += this_write;
468                         xdr_off += this_write;
469                         xfer_len -= this_write;
470                         write_len -= this_write;
471                 }
472         }
473         /* Update the req with the number of chunks actually used */
474         svc_rdma_xdr_encode_reply_array(res_ary, chunk_no);
475
476         return rqstp->rq_res.len;
477 }
478
479 /* This function prepares the portion of the RPCRDMA message to be
480  * sent in the RDMA_SEND. This function is called after data sent via
481  * RDMA has already been transmitted. There are three cases:
482  * - The RPCRDMA header, RPC header, and payload are all sent in a
483  *   single RDMA_SEND. This is the "inline" case.
484  * - The RPCRDMA header and some portion of the RPC header and data
485  *   are sent via this RDMA_SEND and another portion of the data is
486  *   sent via RDMA.
487  * - The RPCRDMA header [NOMSG] is sent in this RDMA_SEND and the RPC
488  *   header and data are all transmitted via RDMA.
489  * In all three cases, this function prepares the RPCRDMA header in
490  * sge[0], the 'type' parameter indicates the type to place in the
491  * RPCRDMA header, and the 'byte_count' field indicates how much of
492  * the XDR to include in this RDMA_SEND.
493  */
494 static int send_reply(struct svcxprt_rdma *rdma,
495                       struct svc_rqst *rqstp,
496                       struct page *page,
497                       struct rpcrdma_msg *rdma_resp,
498                       struct svc_rdma_op_ctxt *ctxt,
499                       struct svc_rdma_req_map *vec,
500                       int byte_count)
501 {
502         struct ib_send_wr send_wr;
503         struct ib_send_wr inv_wr;
504         int sge_no;
505         int sge_bytes;
506         int page_no;
507         int ret;
508
509         /* Post a recv buffer to handle another request. */
510         ret = svc_rdma_post_recv(rdma);
511         if (ret) {
512                 printk(KERN_INFO
513                        "svcrdma: could not post a receive buffer, err=%d."
514                        "Closing transport %p.\n", ret, rdma);
515                 set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags);
516                 svc_rdma_put_context(ctxt, 0);
517                 return -ENOTCONN;
518         }
519
520         /* Prepare the context */
521         ctxt->pages[0] = page;
522         ctxt->count = 1;
523         ctxt->frmr = vec->frmr;
524         if (vec->frmr)
525                 set_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags);
526         else
527                 clear_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags);
528
529         /* Prepare the SGE for the RPCRDMA Header */
530         ctxt->sge[0].addr =
531                 ib_dma_map_page(rdma->sc_cm_id->device,
532                                 page, 0, PAGE_SIZE, DMA_TO_DEVICE);
533         if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr))
534                 goto err;
535         atomic_inc(&rdma->sc_dma_used);
536
537         ctxt->direction = DMA_TO_DEVICE;
538
539         ctxt->sge[0].length = svc_rdma_xdr_get_reply_hdr_len(rdma_resp);
540         ctxt->sge[0].lkey = rdma->sc_dma_lkey;
541
542         /* Determine how many of our SGE are to be transmitted */
543         for (sge_no = 1; byte_count && sge_no < vec->count; sge_no++) {
544                 sge_bytes = min_t(size_t, vec->sge[sge_no].iov_len, byte_count);
545                 byte_count -= sge_bytes;
546                 if (!vec->frmr) {
547                         ctxt->sge[sge_no].addr =
548                                 ib_dma_map_single(rdma->sc_cm_id->device,
549                                                   vec->sge[sge_no].iov_base,
550                                                   sge_bytes, DMA_TO_DEVICE);
551                         if (ib_dma_mapping_error(rdma->sc_cm_id->device,
552                                                  ctxt->sge[sge_no].addr))
553                                 goto err;
554                         atomic_inc(&rdma->sc_dma_used);
555                         ctxt->sge[sge_no].lkey = rdma->sc_dma_lkey;
556                 } else {
557                         ctxt->sge[sge_no].addr = (unsigned long)
558                                 vec->sge[sge_no].iov_base;
559                         ctxt->sge[sge_no].lkey = vec->frmr->mr->lkey;
560                 }
561                 ctxt->sge[sge_no].length = sge_bytes;
562         }
563         BUG_ON(byte_count != 0);
564
565         /* Save all respages in the ctxt and remove them from the
566          * respages array. They are our pages until the I/O
567          * completes.
568          */
569         for (page_no = 0; page_no < rqstp->rq_resused; page_no++) {
570                 ctxt->pages[page_no+1] = rqstp->rq_respages[page_no];
571                 ctxt->count++;
572                 rqstp->rq_respages[page_no] = NULL;
573                 /*
574                  * If there are more pages than SGE, terminate SGE
575                  * list so that svc_rdma_unmap_dma doesn't attempt to
576                  * unmap garbage.
577                  */
578                 if (page_no+1 >= sge_no)
579                         ctxt->sge[page_no+1].length = 0;
580         }
581         BUG_ON(sge_no > rdma->sc_max_sge);
582         BUG_ON(sge_no > ctxt->count);
583         memset(&send_wr, 0, sizeof send_wr);
584         ctxt->wr_op = IB_WR_SEND;
585         send_wr.wr_id = (unsigned long)ctxt;
586         send_wr.sg_list = ctxt->sge;
587         send_wr.num_sge = sge_no;
588         send_wr.opcode = IB_WR_SEND;
589         send_wr.send_flags =  IB_SEND_SIGNALED;
590         if (vec->frmr) {
591                 /* Prepare INVALIDATE WR */
592                 memset(&inv_wr, 0, sizeof inv_wr);
593                 inv_wr.opcode = IB_WR_LOCAL_INV;
594                 inv_wr.send_flags = IB_SEND_SIGNALED;
595                 inv_wr.ex.invalidate_rkey =
596                         vec->frmr->mr->lkey;
597                 send_wr.next = &inv_wr;
598         }
599
600         ret = svc_rdma_send(rdma, &send_wr);
601         if (ret)
602                 goto err;
603
604         return 0;
605
606  err:
607         svc_rdma_put_frmr(rdma, vec->frmr);
608         svc_rdma_put_context(ctxt, 1);
609         return -EIO;
610 }
611
612 void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp)
613 {
614 }
615
616 /*
617  * Return the start of an xdr buffer.
618  */
619 static void *xdr_start(struct xdr_buf *xdr)
620 {
621         return xdr->head[0].iov_base -
622                 (xdr->len -
623                  xdr->page_len -
624                  xdr->tail[0].iov_len -
625                  xdr->head[0].iov_len);
626 }
627
628 int svc_rdma_sendto(struct svc_rqst *rqstp)
629 {
630         struct svc_xprt *xprt = rqstp->rq_xprt;
631         struct svcxprt_rdma *rdma =
632                 container_of(xprt, struct svcxprt_rdma, sc_xprt);
633         struct rpcrdma_msg *rdma_argp;
634         struct rpcrdma_msg *rdma_resp;
635         struct rpcrdma_write_array *reply_ary;
636         enum rpcrdma_proc reply_type;
637         int ret;
638         int inline_bytes;
639         struct page *res_page;
640         struct svc_rdma_op_ctxt *ctxt;
641         struct svc_rdma_req_map *vec;
642
643         dprintk("svcrdma: sending response for rqstp=%p\n", rqstp);
644
645         /* Get the RDMA request header. */
646         rdma_argp = xdr_start(&rqstp->rq_arg);
647
648         /* Build an req vec for the XDR */
649         ctxt = svc_rdma_get_context(rdma);
650         ctxt->direction = DMA_TO_DEVICE;
651         vec = svc_rdma_get_req_map();
652         ret = map_xdr(rdma, &rqstp->rq_res, vec);
653         if (ret)
654                 goto err0;
655         inline_bytes = rqstp->rq_res.len;
656
657         /* Create the RDMA response header */
658         res_page = svc_rdma_get_page();
659         rdma_resp = page_address(res_page);
660         reply_ary = svc_rdma_get_reply_array(rdma_argp);
661         if (reply_ary)
662                 reply_type = RDMA_NOMSG;
663         else
664                 reply_type = RDMA_MSG;
665         svc_rdma_xdr_encode_reply_header(rdma, rdma_argp,
666                                          rdma_resp, reply_type);
667
668         /* Send any write-chunk data and build resp write-list */
669         ret = send_write_chunks(rdma, rdma_argp, rdma_resp,
670                                 rqstp, vec);
671         if (ret < 0) {
672                 printk(KERN_ERR "svcrdma: failed to send write chunks, rc=%d\n",
673                        ret);
674                 goto err1;
675         }
676         inline_bytes -= ret;
677
678         /* Send any reply-list data and update resp reply-list */
679         ret = send_reply_chunks(rdma, rdma_argp, rdma_resp,
680                                 rqstp, vec);
681         if (ret < 0) {
682                 printk(KERN_ERR "svcrdma: failed to send reply chunks, rc=%d\n",
683                        ret);
684                 goto err1;
685         }
686         inline_bytes -= ret;
687
688         ret = send_reply(rdma, rqstp, res_page, rdma_resp, ctxt, vec,
689                          inline_bytes);
690         svc_rdma_put_req_map(vec);
691         dprintk("svcrdma: send_reply returns %d\n", ret);
692         return ret;
693
694  err1:
695         put_page(res_page);
696  err0:
697         svc_rdma_put_req_map(vec);
698         svc_rdma_put_context(ctxt, 0);
699         return ret;
700 }