blob: 9e884383134f6536f6ba5a81e916c5999386ca98 [file] [log] [blame]
Tom Tuckerd5b31be2007-12-12 16:13:23 -06001/*
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/*
53 * Replace the pages in the rq_argpages array with the pages from the SGE in
54 * the RDMA_RECV completion. The SGL should contain full pages up until the
55 * last one.
56 */
57static void rdma_build_arg_xdr(struct svc_rqst *rqstp,
58 struct svc_rdma_op_ctxt *ctxt,
59 u32 byte_count)
60{
61 struct page *page;
62 u32 bc;
63 int sge_no;
64
65 /* Swap the page in the SGE with the page in argpages */
66 page = ctxt->pages[0];
67 put_page(rqstp->rq_pages[0]);
68 rqstp->rq_pages[0] = page;
69
70 /* Set up the XDR head */
71 rqstp->rq_arg.head[0].iov_base = page_address(page);
72 rqstp->rq_arg.head[0].iov_len = min(byte_count, ctxt->sge[0].length);
73 rqstp->rq_arg.len = byte_count;
74 rqstp->rq_arg.buflen = byte_count;
75
76 /* Compute bytes past head in the SGL */
77 bc = byte_count - rqstp->rq_arg.head[0].iov_len;
78
79 /* If data remains, store it in the pagelist */
80 rqstp->rq_arg.page_len = bc;
81 rqstp->rq_arg.page_base = 0;
82 rqstp->rq_arg.pages = &rqstp->rq_pages[1];
83 sge_no = 1;
84 while (bc && sge_no < ctxt->count) {
85 page = ctxt->pages[sge_no];
86 put_page(rqstp->rq_pages[sge_no]);
87 rqstp->rq_pages[sge_no] = page;
88 bc -= min(bc, ctxt->sge[sge_no].length);
89 rqstp->rq_arg.buflen += ctxt->sge[sge_no].length;
90 sge_no++;
91 }
92 rqstp->rq_respages = &rqstp->rq_pages[sge_no];
93
94 /* We should never run out of SGE because the limit is defined to
95 * support the max allowed RPC data length
96 */
97 BUG_ON(bc && (sge_no == ctxt->count));
98 BUG_ON((rqstp->rq_arg.head[0].iov_len + rqstp->rq_arg.page_len)
99 != byte_count);
100 BUG_ON(rqstp->rq_arg.len != byte_count);
101
102 /* If not all pages were used from the SGL, free the remaining ones */
103 bc = sge_no;
104 while (sge_no < ctxt->count) {
105 page = ctxt->pages[sge_no++];
106 put_page(page);
107 }
108 ctxt->count = bc;
109
110 /* Set up tail */
111 rqstp->rq_arg.tail[0].iov_base = NULL;
112 rqstp->rq_arg.tail[0].iov_len = 0;
113}
114
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600115/* Encode a read-chunk-list as an array of IB SGE
116 *
117 * Assumptions:
118 * - chunk[0]->position points to pages[0] at an offset of 0
Tom Tucker146b6df2008-08-12 15:12:10 -0500119 * - pages[] is not physically or virtually contiguous and consists of
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600120 * PAGE_SIZE elements.
121 *
122 * Output:
123 * - sge array pointing into pages[] array.
124 * - chunk_sge array specifying sge index and count for each
125 * chunk in the read list
126 *
127 */
Tom Tucker146b6df2008-08-12 15:12:10 -0500128static int map_read_chunks(struct svcxprt_rdma *xprt,
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600129 struct svc_rqst *rqstp,
130 struct svc_rdma_op_ctxt *head,
131 struct rpcrdma_msg *rmsgp,
Tom Tuckerf820c572008-05-27 17:03:14 -0500132 struct svc_rdma_req_map *rpl_map,
133 struct svc_rdma_req_map *chl_map,
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600134 int ch_count,
135 int byte_count)
136{
137 int sge_no;
138 int sge_bytes;
139 int page_off;
140 int page_no;
141 int ch_bytes;
142 int ch_no;
143 struct rpcrdma_read_chunk *ch;
144
145 sge_no = 0;
146 page_no = 0;
147 page_off = 0;
148 ch = (struct rpcrdma_read_chunk *)&rmsgp->rm_body.rm_chunks[0];
149 ch_no = 0;
150 ch_bytes = ch->rc_target.rs_length;
151 head->arg.head[0] = rqstp->rq_arg.head[0];
152 head->arg.tail[0] = rqstp->rq_arg.tail[0];
153 head->arg.pages = &head->pages[head->count];
Tom Tuckerf820c572008-05-27 17:03:14 -0500154 head->hdr_count = head->count; /* save count of hdr pages */
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600155 head->arg.page_base = 0;
156 head->arg.page_len = ch_bytes;
157 head->arg.len = rqstp->rq_arg.len + ch_bytes;
158 head->arg.buflen = rqstp->rq_arg.buflen + ch_bytes;
159 head->count++;
Tom Tuckerf820c572008-05-27 17:03:14 -0500160 chl_map->ch[0].start = 0;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600161 while (byte_count) {
Tom Tuckerf820c572008-05-27 17:03:14 -0500162 rpl_map->sge[sge_no].iov_base =
163 page_address(rqstp->rq_arg.pages[page_no]) + page_off;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600164 sge_bytes = min_t(int, PAGE_SIZE-page_off, ch_bytes);
Tom Tuckerf820c572008-05-27 17:03:14 -0500165 rpl_map->sge[sge_no].iov_len = sge_bytes;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600166 /*
167 * Don't bump head->count here because the same page
168 * may be used by multiple SGE.
169 */
170 head->arg.pages[page_no] = rqstp->rq_arg.pages[page_no];
171 rqstp->rq_respages = &rqstp->rq_arg.pages[page_no+1];
172
173 byte_count -= sge_bytes;
174 ch_bytes -= sge_bytes;
175 sge_no++;
176 /*
177 * If all bytes for this chunk have been mapped to an
178 * SGE, move to the next SGE
179 */
180 if (ch_bytes == 0) {
Tom Tuckerf820c572008-05-27 17:03:14 -0500181 chl_map->ch[ch_no].count =
182 sge_no - chl_map->ch[ch_no].start;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600183 ch_no++;
184 ch++;
Tom Tuckerf820c572008-05-27 17:03:14 -0500185 chl_map->ch[ch_no].start = sge_no;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600186 ch_bytes = ch->rc_target.rs_length;
187 /* If bytes remaining account for next chunk */
188 if (byte_count) {
189 head->arg.page_len += ch_bytes;
190 head->arg.len += ch_bytes;
191 head->arg.buflen += ch_bytes;
192 }
193 }
194 /*
195 * If this SGE consumed all of the page, move to the
196 * next page
197 */
198 if ((sge_bytes + page_off) == PAGE_SIZE) {
199 page_no++;
200 page_off = 0;
201 /*
202 * If there are still bytes left to map, bump
203 * the page count
204 */
205 if (byte_count)
206 head->count++;
207 } else
208 page_off += sge_bytes;
209 }
210 BUG_ON(byte_count != 0);
211 return sge_no;
212}
213
Tom Tucker146b6df2008-08-12 15:12:10 -0500214/* Map a read-chunk-list to an XDR and fast register the page-list.
215 *
216 * Assumptions:
217 * - chunk[0] position points to pages[0] at an offset of 0
218 * - pages[] will be made physically contiguous by creating a one-off memory
219 * region using the fastreg verb.
220 * - byte_count is # of bytes in read-chunk-list
221 * - ch_count is # of chunks in read-chunk-list
222 *
223 * Output:
224 * - sge array pointing into pages[] array.
225 * - chunk_sge array specifying sge index and count for each
226 * chunk in the read list
227 */
228static int fast_reg_read_chunks(struct svcxprt_rdma *xprt,
229 struct svc_rqst *rqstp,
230 struct svc_rdma_op_ctxt *head,
231 struct rpcrdma_msg *rmsgp,
232 struct svc_rdma_req_map *rpl_map,
233 struct svc_rdma_req_map *chl_map,
234 int ch_count,
235 int byte_count)
236{
237 int page_no;
238 int ch_no;
239 u32 offset;
240 struct rpcrdma_read_chunk *ch;
241 struct svc_rdma_fastreg_mr *frmr;
242 int ret = 0;
243
244 frmr = svc_rdma_get_frmr(xprt);
245 if (IS_ERR(frmr))
246 return -ENOMEM;
247
248 head->frmr = frmr;
249 head->arg.head[0] = rqstp->rq_arg.head[0];
250 head->arg.tail[0] = rqstp->rq_arg.tail[0];
251 head->arg.pages = &head->pages[head->count];
252 head->hdr_count = head->count; /* save count of hdr pages */
253 head->arg.page_base = 0;
254 head->arg.page_len = byte_count;
255 head->arg.len = rqstp->rq_arg.len + byte_count;
256 head->arg.buflen = rqstp->rq_arg.buflen + byte_count;
257
258 /* Fast register the page list */
259 frmr->kva = page_address(rqstp->rq_arg.pages[0]);
260 frmr->direction = DMA_FROM_DEVICE;
261 frmr->access_flags = (IB_ACCESS_LOCAL_WRITE|IB_ACCESS_REMOTE_WRITE);
262 frmr->map_len = byte_count;
263 frmr->page_list_len = PAGE_ALIGN(byte_count) >> PAGE_SHIFT;
264 for (page_no = 0; page_no < frmr->page_list_len; page_no++) {
265 frmr->page_list->page_list[page_no] =
266 ib_dma_map_single(xprt->sc_cm_id->device,
267 page_address(rqstp->rq_arg.pages[page_no]),
Steve Wised0687be2009-04-03 15:18:24 -0500268 PAGE_SIZE, DMA_FROM_DEVICE);
Tom Tucker146b6df2008-08-12 15:12:10 -0500269 if (ib_dma_mapping_error(xprt->sc_cm_id->device,
270 frmr->page_list->page_list[page_no]))
271 goto fatal_err;
272 atomic_inc(&xprt->sc_dma_used);
273 head->arg.pages[page_no] = rqstp->rq_arg.pages[page_no];
274 }
275 head->count += page_no;
276
277 /* rq_respages points one past arg pages */
278 rqstp->rq_respages = &rqstp->rq_arg.pages[page_no];
279
280 /* Create the reply and chunk maps */
281 offset = 0;
282 ch = (struct rpcrdma_read_chunk *)&rmsgp->rm_body.rm_chunks[0];
283 for (ch_no = 0; ch_no < ch_count; ch_no++) {
284 rpl_map->sge[ch_no].iov_base = frmr->kva + offset;
285 rpl_map->sge[ch_no].iov_len = ch->rc_target.rs_length;
286 chl_map->ch[ch_no].count = 1;
287 chl_map->ch[ch_no].start = ch_no;
288 offset += ch->rc_target.rs_length;
289 ch++;
290 }
291
292 ret = svc_rdma_fastreg(xprt, frmr);
293 if (ret)
294 goto fatal_err;
295
296 return ch_no;
297
298 fatal_err:
299 printk("svcrdma: error fast registering xdr for xprt %p", xprt);
300 svc_rdma_put_frmr(xprt, frmr);
301 return -EIO;
302}
303
304static int rdma_set_ctxt_sge(struct svcxprt_rdma *xprt,
305 struct svc_rdma_op_ctxt *ctxt,
306 struct svc_rdma_fastreg_mr *frmr,
307 struct kvec *vec,
308 u64 *sgl_offset,
309 int count)
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600310{
311 int i;
312
313 ctxt->count = count;
Tom Tuckerf820c572008-05-27 17:03:14 -0500314 ctxt->direction = DMA_FROM_DEVICE;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600315 for (i = 0; i < count; i++) {
Tom Tucker146b6df2008-08-12 15:12:10 -0500316 ctxt->sge[i].length = 0; /* in case map fails */
317 if (!frmr) {
318 ctxt->sge[i].addr =
319 ib_dma_map_single(xprt->sc_cm_id->device,
320 vec[i].iov_base,
321 vec[i].iov_len,
322 DMA_FROM_DEVICE);
323 if (ib_dma_mapping_error(xprt->sc_cm_id->device,
324 ctxt->sge[i].addr))
325 return -EINVAL;
326 ctxt->sge[i].lkey = xprt->sc_dma_lkey;
327 atomic_inc(&xprt->sc_dma_used);
328 } else {
329 ctxt->sge[i].addr = (unsigned long)vec[i].iov_base;
330 ctxt->sge[i].lkey = frmr->mr->lkey;
331 }
Tom Tuckerf820c572008-05-27 17:03:14 -0500332 ctxt->sge[i].length = vec[i].iov_len;
Tom Tuckerf820c572008-05-27 17:03:14 -0500333 *sgl_offset = *sgl_offset + vec[i].iov_len;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600334 }
Tom Tucker146b6df2008-08-12 15:12:10 -0500335 return 0;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600336}
337
338static int rdma_read_max_sge(struct svcxprt_rdma *xprt, int sge_count)
339{
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600340 if ((RDMA_TRANSPORT_IWARP ==
341 rdma_node_get_transport(xprt->sc_cm_id->
342 device->node_type))
343 && sge_count > 1)
344 return 1;
345 else
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600346 return min_t(int, sge_count, xprt->sc_max_sge);
347}
348
349/*
350 * Use RDMA_READ to read data from the advertised client buffer into the
351 * XDR stream starting at rq_arg.head[0].iov_base.
352 * Each chunk in the array
353 * contains the following fields:
354 * discrim - '1', This isn't used for data placement
355 * position - The xdr stream offset (the same for every chunk)
356 * handle - RMR for client memory region
357 * length - data transfer length
358 * offset - 64 bit tagged offset in remote memory region
359 *
360 * On our side, we need to read into a pagelist. The first page immediately
361 * follows the RPC header.
362 *
Tom Tuckerd16d4002008-05-06 10:04:50 -0500363 * This function returns:
364 * 0 - No error and no read-list found.
365 *
366 * 1 - Successful read-list processing. The data is not yet in
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600367 * the pagelist and therefore the RPC request must be deferred. The
368 * I/O completion will enqueue the transport again and
369 * svc_rdma_recvfrom will complete the request.
370 *
Tom Tuckerd16d4002008-05-06 10:04:50 -0500371 * <0 - Error processing/posting read-list.
372 *
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600373 * NOTE: The ctxt must not be touched after the last WR has been posted
374 * because the I/O completion processing may occur on another
375 * processor and free / modify the context. Ne touche pas!
376 */
377static int rdma_read_xdr(struct svcxprt_rdma *xprt,
378 struct rpcrdma_msg *rmsgp,
379 struct svc_rqst *rqstp,
380 struct svc_rdma_op_ctxt *hdr_ctxt)
381{
382 struct ib_send_wr read_wr;
Tom Tucker146b6df2008-08-12 15:12:10 -0500383 struct ib_send_wr inv_wr;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600384 int err = 0;
385 int ch_no;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600386 int ch_count;
387 int byte_count;
388 int sge_count;
389 u64 sgl_offset;
390 struct rpcrdma_read_chunk *ch;
391 struct svc_rdma_op_ctxt *ctxt = NULL;
Tom Tuckerf820c572008-05-27 17:03:14 -0500392 struct svc_rdma_req_map *rpl_map;
393 struct svc_rdma_req_map *chl_map;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600394
395 /* If no read list is present, return 0 */
396 ch = svc_rdma_get_read_chunk(rmsgp);
397 if (!ch)
398 return 0;
399
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600400 svc_rdma_rcl_chunk_counts(ch, &ch_count, &byte_count);
Tom Tuckera6f911c2008-05-13 09:16:05 -0500401 if (ch_count > RPCSVC_MAXPAGES)
402 return -EINVAL;
Tom Tucker146b6df2008-08-12 15:12:10 -0500403
Christian Engelmayer59fb3062009-06-14 00:05:26 +0200404 /* Allocate temporary reply and chunk maps */
405 rpl_map = svc_rdma_get_req_map();
406 chl_map = svc_rdma_get_req_map();
407
Tom Tucker146b6df2008-08-12 15:12:10 -0500408 if (!xprt->sc_frmr_pg_list_len)
409 sge_count = map_read_chunks(xprt, rqstp, hdr_ctxt, rmsgp,
410 rpl_map, chl_map, ch_count,
411 byte_count);
412 else
413 sge_count = fast_reg_read_chunks(xprt, rqstp, hdr_ctxt, rmsgp,
414 rpl_map, chl_map, ch_count,
415 byte_count);
416 if (sge_count < 0) {
417 err = -EIO;
418 goto out;
419 }
420
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600421 sgl_offset = 0;
422 ch_no = 0;
423
424 for (ch = (struct rpcrdma_read_chunk *)&rmsgp->rm_body.rm_chunks[0];
425 ch->rc_discrim != 0; ch++, ch_no++) {
426next_sge:
Tom Tucker02e74522008-04-30 19:50:56 -0500427 ctxt = svc_rdma_get_context(xprt);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600428 ctxt->direction = DMA_FROM_DEVICE;
Tom Tucker146b6df2008-08-12 15:12:10 -0500429 ctxt->frmr = hdr_ctxt->frmr;
430 ctxt->read_hdr = NULL;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600431 clear_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags);
Tom Tucker146b6df2008-08-12 15:12:10 -0500432 clear_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600433
434 /* Prepare READ WR */
435 memset(&read_wr, 0, sizeof read_wr);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600436 read_wr.wr_id = (unsigned long)ctxt;
437 read_wr.opcode = IB_WR_RDMA_READ;
Tom Tucker146b6df2008-08-12 15:12:10 -0500438 ctxt->wr_op = read_wr.opcode;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600439 read_wr.send_flags = IB_SEND_SIGNALED;
440 read_wr.wr.rdma.rkey = ch->rc_target.rs_handle;
441 read_wr.wr.rdma.remote_addr =
442 get_unaligned(&(ch->rc_target.rs_offset)) +
443 sgl_offset;
Tom Tuckerf820c572008-05-27 17:03:14 -0500444 read_wr.sg_list = ctxt->sge;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600445 read_wr.num_sge =
Tom Tuckerf820c572008-05-27 17:03:14 -0500446 rdma_read_max_sge(xprt, chl_map->ch[ch_no].count);
Tom Tucker146b6df2008-08-12 15:12:10 -0500447 err = rdma_set_ctxt_sge(xprt, ctxt, hdr_ctxt->frmr,
448 &rpl_map->sge[chl_map->ch[ch_no].start],
449 &sgl_offset,
450 read_wr.num_sge);
451 if (err) {
452 svc_rdma_unmap_dma(ctxt);
453 svc_rdma_put_context(ctxt, 0);
454 goto out;
455 }
Tom Tuckerc8237a52008-03-25 22:27:19 -0400456 if (((ch+1)->rc_discrim == 0) &&
Tom Tuckerf820c572008-05-27 17:03:14 -0500457 (read_wr.num_sge == chl_map->ch[ch_no].count)) {
Tom Tuckerc8237a52008-03-25 22:27:19 -0400458 /*
459 * Mark the last RDMA_READ with a bit to
460 * indicate all RPC data has been fetched from
461 * the client and the RPC needs to be enqueued.
462 */
463 set_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags);
Tom Tucker146b6df2008-08-12 15:12:10 -0500464 if (hdr_ctxt->frmr) {
465 set_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags);
466 /*
467 * Invalidate the local MR used to map the data
468 * sink.
469 */
470 if (xprt->sc_dev_caps &
471 SVCRDMA_DEVCAP_READ_W_INV) {
472 read_wr.opcode =
473 IB_WR_RDMA_READ_WITH_INV;
474 ctxt->wr_op = read_wr.opcode;
475 read_wr.ex.invalidate_rkey =
476 ctxt->frmr->mr->lkey;
477 } else {
478 /* Prepare INVALIDATE WR */
479 memset(&inv_wr, 0, sizeof inv_wr);
480 inv_wr.opcode = IB_WR_LOCAL_INV;
481 inv_wr.send_flags = IB_SEND_SIGNALED;
482 inv_wr.ex.invalidate_rkey =
483 hdr_ctxt->frmr->mr->lkey;
484 read_wr.next = &inv_wr;
485 }
486 }
Tom Tucker02e74522008-04-30 19:50:56 -0500487 ctxt->read_hdr = hdr_ctxt;
Tom Tuckerc8237a52008-03-25 22:27:19 -0400488 }
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600489 /* Post the read */
490 err = svc_rdma_send(xprt, &read_wr);
491 if (err) {
Tom Tucker02e74522008-04-30 19:50:56 -0500492 printk(KERN_ERR "svcrdma: Error %d posting RDMA_READ\n",
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600493 err);
Tom Tucker02e74522008-04-30 19:50:56 -0500494 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
495 svc_rdma_put_context(ctxt, 0);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600496 goto out;
497 }
498 atomic_inc(&rdma_stat_read);
499
Tom Tuckerf820c572008-05-27 17:03:14 -0500500 if (read_wr.num_sge < chl_map->ch[ch_no].count) {
501 chl_map->ch[ch_no].count -= read_wr.num_sge;
502 chl_map->ch[ch_no].start += read_wr.num_sge;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600503 goto next_sge;
504 }
505 sgl_offset = 0;
Tom Tucker02e74522008-04-30 19:50:56 -0500506 err = 1;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600507 }
508
509 out:
Tom Tuckerf820c572008-05-27 17:03:14 -0500510 svc_rdma_put_req_map(rpl_map);
511 svc_rdma_put_req_map(chl_map);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600512
513 /* Detach arg pages. svc_recv will replenish them */
514 for (ch_no = 0; &rqstp->rq_pages[ch_no] < rqstp->rq_respages; ch_no++)
515 rqstp->rq_pages[ch_no] = NULL;
516
517 /*
518 * Detach res pages. svc_release must see a resused count of
519 * zero or it will attempt to put them.
520 */
521 while (rqstp->rq_resused)
522 rqstp->rq_respages[--rqstp->rq_resused] = NULL;
523
Tom Tucker02e74522008-04-30 19:50:56 -0500524 return err;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600525}
526
527static int rdma_read_complete(struct svc_rqst *rqstp,
Tom Tucker02e74522008-04-30 19:50:56 -0500528 struct svc_rdma_op_ctxt *head)
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600529{
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600530 int page_no;
531 int ret;
532
533 BUG_ON(!head);
534
535 /* Copy RPC pages */
536 for (page_no = 0; page_no < head->count; page_no++) {
537 put_page(rqstp->rq_pages[page_no]);
538 rqstp->rq_pages[page_no] = head->pages[page_no];
539 }
540 /* Point rq_arg.pages past header */
Tom Tuckerf820c572008-05-27 17:03:14 -0500541 rqstp->rq_arg.pages = &rqstp->rq_pages[head->hdr_count];
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600542 rqstp->rq_arg.page_len = head->arg.page_len;
543 rqstp->rq_arg.page_base = head->arg.page_base;
544
545 /* rq_respages starts after the last arg page */
546 rqstp->rq_respages = &rqstp->rq_arg.pages[page_no];
547 rqstp->rq_resused = 0;
548
549 /* Rebuild rq_arg head and tail. */
550 rqstp->rq_arg.head[0] = head->arg.head[0];
551 rqstp->rq_arg.tail[0] = head->arg.tail[0];
552 rqstp->rq_arg.len = head->arg.len;
553 rqstp->rq_arg.buflen = head->arg.buflen;
554
Tom Tucker02e74522008-04-30 19:50:56 -0500555 /* Free the context */
556 svc_rdma_put_context(head, 0);
557
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600558 /* XXX: What should this be? */
559 rqstp->rq_prot = IPPROTO_MAX;
Tom Tucker69500c42008-05-07 13:49:58 -0500560 svc_xprt_copy_addrs(rqstp, rqstp->rq_xprt);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600561
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600562 ret = rqstp->rq_arg.head[0].iov_len
563 + rqstp->rq_arg.page_len
564 + rqstp->rq_arg.tail[0].iov_len;
565 dprintk("svcrdma: deferred read ret=%d, rq_arg.len =%d, "
566 "rq_arg.head[0].iov_base=%p, rq_arg.head[0].iov_len = %zd\n",
567 ret, rqstp->rq_arg.len, rqstp->rq_arg.head[0].iov_base,
568 rqstp->rq_arg.head[0].iov_len);
569
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600570 svc_xprt_received(rqstp->rq_xprt);
571 return ret;
572}
573
574/*
575 * Set up the rqstp thread context to point to the RQ buffer. If
576 * necessary, pull additional data from the client with an RDMA_READ
577 * request.
578 */
579int svc_rdma_recvfrom(struct svc_rqst *rqstp)
580{
581 struct svc_xprt *xprt = rqstp->rq_xprt;
582 struct svcxprt_rdma *rdma_xprt =
583 container_of(xprt, struct svcxprt_rdma, sc_xprt);
584 struct svc_rdma_op_ctxt *ctxt = NULL;
585 struct rpcrdma_msg *rmsgp;
586 int ret = 0;
587 int len;
588
589 dprintk("svcrdma: rqstp=%p\n", rqstp);
590
Tom Tucker24b8b442008-08-13 11:05:41 -0500591 spin_lock_bh(&rdma_xprt->sc_rq_dto_lock);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600592 if (!list_empty(&rdma_xprt->sc_read_complete_q)) {
593 ctxt = list_entry(rdma_xprt->sc_read_complete_q.next,
594 struct svc_rdma_op_ctxt,
595 dto_q);
596 list_del_init(&ctxt->dto_q);
597 }
Tom Tucker24b8b442008-08-13 11:05:41 -0500598 if (ctxt) {
599 spin_unlock_bh(&rdma_xprt->sc_rq_dto_lock);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600600 return rdma_read_complete(rqstp, ctxt);
Tom Tucker24b8b442008-08-13 11:05:41 -0500601 }
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600602
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600603 if (!list_empty(&rdma_xprt->sc_rq_dto_q)) {
604 ctxt = list_entry(rdma_xprt->sc_rq_dto_q.next,
605 struct svc_rdma_op_ctxt,
606 dto_q);
607 list_del_init(&ctxt->dto_q);
608 } else {
609 atomic_inc(&rdma_stat_rq_starve);
610 clear_bit(XPT_DATA, &xprt->xpt_flags);
611 ctxt = NULL;
612 }
613 spin_unlock_bh(&rdma_xprt->sc_rq_dto_lock);
614 if (!ctxt) {
615 /* This is the EAGAIN path. The svc_recv routine will
616 * return -EAGAIN, the nfsd thread will go to call into
617 * svc_recv again and we shouldn't be on the active
618 * transport list
619 */
620 if (test_bit(XPT_CLOSE, &xprt->xpt_flags))
621 goto close_out;
622
623 BUG_ON(ret);
624 goto out;
625 }
626 dprintk("svcrdma: processing ctxt=%p on xprt=%p, rqstp=%p, status=%d\n",
627 ctxt, rdma_xprt, rqstp, ctxt->wc_status);
628 BUG_ON(ctxt->wc_status != IB_WC_SUCCESS);
629 atomic_inc(&rdma_stat_recv);
630
631 /* Build up the XDR from the receive buffers. */
632 rdma_build_arg_xdr(rqstp, ctxt, ctxt->byte_len);
633
634 /* Decode the RDMA header. */
635 len = svc_rdma_xdr_decode_req(&rmsgp, rqstp);
636 rqstp->rq_xprt_hlen = len;
637
638 /* If the request is invalid, reply with an error */
639 if (len < 0) {
640 if (len == -ENOSYS)
Tom Tucker008fdbc2008-05-07 15:47:42 -0500641 svc_rdma_send_error(rdma_xprt, rmsgp, ERR_VERS);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600642 goto close_out;
643 }
644
Tom Tuckerd16d4002008-05-06 10:04:50 -0500645 /* Read read-list data. */
646 ret = rdma_read_xdr(rdma_xprt, rmsgp, rqstp, ctxt);
647 if (ret > 0) {
648 /* read-list posted, defer until data received from client. */
Ilpo Järvinenb1721d22008-12-14 23:19:48 -0800649 goto defer;
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600650 }
Tom Tuckerd16d4002008-05-06 10:04:50 -0500651 if (ret < 0) {
652 /* Post of read-list failed, free context. */
653 svc_rdma_put_context(ctxt, 1);
654 return 0;
655 }
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600656
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600657 ret = rqstp->rq_arg.head[0].iov_len
658 + rqstp->rq_arg.page_len
659 + rqstp->rq_arg.tail[0].iov_len;
660 svc_rdma_put_context(ctxt, 0);
661 out:
662 dprintk("svcrdma: ret = %d, rq_arg.len =%d, "
663 "rq_arg.head[0].iov_base=%p, rq_arg.head[0].iov_len = %zd\n",
664 ret, rqstp->rq_arg.len,
665 rqstp->rq_arg.head[0].iov_base,
666 rqstp->rq_arg.head[0].iov_len);
667 rqstp->rq_prot = IPPROTO_MAX;
668 svc_xprt_copy_addrs(rqstp, xprt);
669 svc_xprt_received(xprt);
670 return ret;
671
672 close_out:
Tom Tucker0e7f0112008-04-23 16:49:54 -0500673 if (ctxt)
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600674 svc_rdma_put_context(ctxt, 1);
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600675 dprintk("svcrdma: transport %p is closing\n", xprt);
676 /*
677 * Set the close bit and enqueue it. svc_recv will see the
678 * close bit and call svc_xprt_delete
679 */
680 set_bit(XPT_CLOSE, &xprt->xpt_flags);
Ilpo Järvinenb1721d22008-12-14 23:19:48 -0800681defer:
Tom Tuckerd5b31be2007-12-12 16:13:23 -0600682 svc_xprt_received(xprt);
683 return 0;
684}