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1/*
2 * Copyright (c) 2006 Oracle. 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
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 *
32 */
33#include <linux/kernel.h>
34#include <linux/slab.h>
35#include <linux/export.h>
36
37#include "rds.h"
38
39static unsigned int rds_exthdr_size[__RDS_EXTHDR_MAX] = {
40[RDS_EXTHDR_NONE] = 0,
41[RDS_EXTHDR_VERSION] = sizeof(struct rds_ext_header_version),
42[RDS_EXTHDR_RDMA] = sizeof(struct rds_ext_header_rdma),
43[RDS_EXTHDR_RDMA_DEST] = sizeof(struct rds_ext_header_rdma_dest),
44};
45
46
47void rds_message_addref(struct rds_message *rm)
48{
49 rdsdebug("addref rm %p ref %d\n", rm, atomic_read(&rm->m_refcount));
50 atomic_inc(&rm->m_refcount);
51}
52EXPORT_SYMBOL_GPL(rds_message_addref);
53
54/*
55 * This relies on dma_map_sg() not touching sg[].page during merging.
56 */
57static void rds_message_purge(struct rds_message *rm)
58{
59 unsigned long i;
60
61 if (unlikely(test_bit(RDS_MSG_PAGEVEC, &rm->m_flags)))
62 return;
63
64 for (i = 0; i < rm->data.op_nents; i++) {
65 rdsdebug("putting data page %p\n", (void *)sg_page(&rm->data.op_sg[i]));
66 /* XXX will have to put_page for page refs */
67 __free_page(sg_page(&rm->data.op_sg[i]));
68 }
69 rm->data.op_nents = 0;
70
71 if (rm->rdma.op_active)
72 rds_rdma_free_op(&rm->rdma);
73 if (rm->rdma.op_rdma_mr)
74 rds_mr_put(rm->rdma.op_rdma_mr);
75
76 if (rm->atomic.op_active)
77 rds_atomic_free_op(&rm->atomic);
78 if (rm->atomic.op_rdma_mr)
79 rds_mr_put(rm->atomic.op_rdma_mr);
80}
81
82void rds_message_put(struct rds_message *rm)
83{
84 rdsdebug("put rm %p ref %d\n", rm, atomic_read(&rm->m_refcount));
85 WARN(!atomic_read(&rm->m_refcount), "danger refcount zero on %p\n", rm);
86 if (atomic_dec_and_test(&rm->m_refcount)) {
87 BUG_ON(!list_empty(&rm->m_sock_item));
88 BUG_ON(!list_empty(&rm->m_conn_item));
89 rds_message_purge(rm);
90
91 kfree(rm);
92 }
93}
94EXPORT_SYMBOL_GPL(rds_message_put);
95
96void rds_message_populate_header(struct rds_header *hdr, __be16 sport,
97 __be16 dport, u64 seq)
98{
99 hdr->h_flags = 0;
100 hdr->h_sport = sport;
101 hdr->h_dport = dport;
102 hdr->h_sequence = cpu_to_be64(seq);
103 hdr->h_exthdr[0] = RDS_EXTHDR_NONE;
104}
105EXPORT_SYMBOL_GPL(rds_message_populate_header);
106
107int rds_message_add_extension(struct rds_header *hdr, unsigned int type,
108 const void *data, unsigned int len)
109{
110 unsigned int ext_len = sizeof(u8) + len;
111 unsigned char *dst;
112
113 /* For now, refuse to add more than one extension header */
114 if (hdr->h_exthdr[0] != RDS_EXTHDR_NONE)
115 return 0;
116
117 if (type >= __RDS_EXTHDR_MAX || len != rds_exthdr_size[type])
118 return 0;
119
120 if (ext_len >= RDS_HEADER_EXT_SPACE)
121 return 0;
122 dst = hdr->h_exthdr;
123
124 *dst++ = type;
125 memcpy(dst, data, len);
126
127 dst[len] = RDS_EXTHDR_NONE;
128 return 1;
129}
130EXPORT_SYMBOL_GPL(rds_message_add_extension);
131
132/*
133 * If a message has extension headers, retrieve them here.
134 * Call like this:
135 *
136 * unsigned int pos = 0;
137 *
138 * while (1) {
139 * buflen = sizeof(buffer);
140 * type = rds_message_next_extension(hdr, &pos, buffer, &buflen);
141 * if (type == RDS_EXTHDR_NONE)
142 * break;
143 * ...
144 * }
145 */
146int rds_message_next_extension(struct rds_header *hdr,
147 unsigned int *pos, void *buf, unsigned int *buflen)
148{
149 unsigned int offset, ext_type, ext_len;
150 u8 *src = hdr->h_exthdr;
151
152 offset = *pos;
153 if (offset >= RDS_HEADER_EXT_SPACE)
154 goto none;
155
156 /* Get the extension type and length. For now, the
157 * length is implied by the extension type. */
158 ext_type = src[offset++];
159
160 if (ext_type == RDS_EXTHDR_NONE || ext_type >= __RDS_EXTHDR_MAX)
161 goto none;
162 ext_len = rds_exthdr_size[ext_type];
163 if (offset + ext_len > RDS_HEADER_EXT_SPACE)
164 goto none;
165
166 *pos = offset + ext_len;
167 if (ext_len < *buflen)
168 *buflen = ext_len;
169 memcpy(buf, src + offset, *buflen);
170 return ext_type;
171
172none:
173 *pos = RDS_HEADER_EXT_SPACE;
174 *buflen = 0;
175 return RDS_EXTHDR_NONE;
176}
177
178int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset)
179{
180 struct rds_ext_header_rdma_dest ext_hdr;
181
182 ext_hdr.h_rdma_rkey = cpu_to_be32(r_key);
183 ext_hdr.h_rdma_offset = cpu_to_be32(offset);
184 return rds_message_add_extension(hdr, RDS_EXTHDR_RDMA_DEST, &ext_hdr, sizeof(ext_hdr));
185}
186EXPORT_SYMBOL_GPL(rds_message_add_rdma_dest_extension);
187
188/*
189 * Each rds_message is allocated with extra space for the scatterlist entries
190 * rds ops will need. This is to minimize memory allocation count. Then, each rds op
191 * can grab SGs when initializing its part of the rds_message.
192 */
193struct rds_message *rds_message_alloc(unsigned int extra_len, gfp_t gfp)
194{
195 struct rds_message *rm;
196
197 if (extra_len > KMALLOC_MAX_SIZE - sizeof(struct rds_message))
198 return NULL;
199
200 rm = kzalloc(sizeof(struct rds_message) + extra_len, gfp);
201 if (!rm)
202 goto out;
203
204 rm->m_used_sgs = 0;
205 rm->m_total_sgs = extra_len / sizeof(struct scatterlist);
206
207 atomic_set(&rm->m_refcount, 1);
208 INIT_LIST_HEAD(&rm->m_sock_item);
209 INIT_LIST_HEAD(&rm->m_conn_item);
210 spin_lock_init(&rm->m_rs_lock);
211 init_waitqueue_head(&rm->m_flush_wait);
212
213out:
214 return rm;
215}
216
217/*
218 * RDS ops use this to grab SG entries from the rm's sg pool.
219 */
220struct scatterlist *rds_message_alloc_sgs(struct rds_message *rm, int nents)
221{
222 struct scatterlist *sg_first = (struct scatterlist *) &rm[1];
223 struct scatterlist *sg_ret;
224
225 WARN_ON(rm->m_used_sgs + nents > rm->m_total_sgs);
226 WARN_ON(!nents);
227
228 if (rm->m_used_sgs + nents > rm->m_total_sgs)
229 return NULL;
230
231 sg_ret = &sg_first[rm->m_used_sgs];
232 sg_init_table(sg_ret, nents);
233 rm->m_used_sgs += nents;
234
235 return sg_ret;
236}
237
238struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len)
239{
240 struct rds_message *rm;
241 unsigned int i;
242 int num_sgs = ceil(total_len, PAGE_SIZE);
243 int extra_bytes = num_sgs * sizeof(struct scatterlist);
244
245 rm = rds_message_alloc(extra_bytes, GFP_NOWAIT);
246 if (!rm)
247 return ERR_PTR(-ENOMEM);
248
249 set_bit(RDS_MSG_PAGEVEC, &rm->m_flags);
250 rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len);
251 rm->data.op_nents = ceil(total_len, PAGE_SIZE);
252 rm->data.op_sg = rds_message_alloc_sgs(rm, num_sgs);
253 if (!rm->data.op_sg) {
254 rds_message_put(rm);
255 return ERR_PTR(-ENOMEM);
256 }
257
258 for (i = 0; i < rm->data.op_nents; ++i) {
259 sg_set_page(&rm->data.op_sg[i],
260 virt_to_page(page_addrs[i]),
261 PAGE_SIZE, 0);
262 }
263
264 return rm;
265}
266
267int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from)
268{
269 unsigned long to_copy, nbytes;
270 unsigned long sg_off;
271 struct scatterlist *sg;
272 int ret = 0;
273
274 rm->m_inc.i_hdr.h_len = cpu_to_be32(iov_iter_count(from));
275
276 /*
277 * now allocate and copy in the data payload.
278 */
279 sg = rm->data.op_sg;
280 sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */
281
282 while (iov_iter_count(from)) {
283 if (!sg_page(sg)) {
284 ret = rds_page_remainder_alloc(sg, iov_iter_count(from),
285 GFP_HIGHUSER);
286 if (ret)
287 return ret;
288 rm->data.op_nents++;
289 sg_off = 0;
290 }
291
292 to_copy = min_t(unsigned long, iov_iter_count(from),
293 sg->length - sg_off);
294
295 rds_stats_add(s_copy_from_user, to_copy);
296 nbytes = copy_page_from_iter(sg_page(sg), sg->offset + sg_off,
297 to_copy, from);
298 if (nbytes != to_copy)
299 return -EFAULT;
300
301 sg_off += to_copy;
302
303 if (sg_off == sg->length)
304 sg++;
305 }
306
307 return ret;
308}
309
310int rds_message_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to)
311{
312 struct rds_message *rm;
313 struct scatterlist *sg;
314 unsigned long to_copy;
315 unsigned long vec_off;
316 int copied;
317 int ret;
318 u32 len;
319
320 rm = container_of(inc, struct rds_message, m_inc);
321 len = be32_to_cpu(rm->m_inc.i_hdr.h_len);
322
323 sg = rm->data.op_sg;
324 vec_off = 0;
325 copied = 0;
326
327 while (iov_iter_count(to) && copied < len) {
328 to_copy = min_t(unsigned long, iov_iter_count(to),
329 sg->length - vec_off);
330 to_copy = min_t(unsigned long, to_copy, len - copied);
331
332 rds_stats_add(s_copy_to_user, to_copy);
333 ret = copy_page_to_iter(sg_page(sg), sg->offset + vec_off,
334 to_copy, to);
335 if (ret != to_copy)
336 return -EFAULT;
337
338 vec_off += to_copy;
339 copied += to_copy;
340
341 if (vec_off == sg->length) {
342 vec_off = 0;
343 sg++;
344 }
345 }
346
347 return copied;
348}
349
350/*
351 * If the message is still on the send queue, wait until the transport
352 * is done with it. This is particularly important for RDMA operations.
353 */
354void rds_message_wait(struct rds_message *rm)
355{
356 wait_event_interruptible(rm->m_flush_wait,
357 !test_bit(RDS_MSG_MAPPED, &rm->m_flags));
358}
359
360void rds_message_unmapped(struct rds_message *rm)
361{
362 clear_bit(RDS_MSG_MAPPED, &rm->m_flags);
363 wake_up_interruptible(&rm->m_flush_wait);
364}
365EXPORT_SYMBOL_GPL(rds_message_unmapped);
366
1/*
2 * Copyright (c) 2006 Oracle. 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
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 *
32 */
33#include <linux/kernel.h>
34#include <linux/slab.h>
35
36#include "rds.h"
37
38static unsigned int rds_exthdr_size[__RDS_EXTHDR_MAX] = {
39[RDS_EXTHDR_NONE] = 0,
40[RDS_EXTHDR_VERSION] = sizeof(struct rds_ext_header_version),
41[RDS_EXTHDR_RDMA] = sizeof(struct rds_ext_header_rdma),
42[RDS_EXTHDR_RDMA_DEST] = sizeof(struct rds_ext_header_rdma_dest),
43};
44
45
46void rds_message_addref(struct rds_message *rm)
47{
48 rdsdebug("addref rm %p ref %d\n", rm, atomic_read(&rm->m_refcount));
49 atomic_inc(&rm->m_refcount);
50}
51EXPORT_SYMBOL_GPL(rds_message_addref);
52
53/*
54 * This relies on dma_map_sg() not touching sg[].page during merging.
55 */
56static void rds_message_purge(struct rds_message *rm)
57{
58 unsigned long i;
59
60 if (unlikely(test_bit(RDS_MSG_PAGEVEC, &rm->m_flags)))
61 return;
62
63 for (i = 0; i < rm->data.op_nents; i++) {
64 rdsdebug("putting data page %p\n", (void *)sg_page(&rm->data.op_sg[i]));
65 /* XXX will have to put_page for page refs */
66 __free_page(sg_page(&rm->data.op_sg[i]));
67 }
68 rm->data.op_nents = 0;
69
70 if (rm->rdma.op_active)
71 rds_rdma_free_op(&rm->rdma);
72 if (rm->rdma.op_rdma_mr)
73 rds_mr_put(rm->rdma.op_rdma_mr);
74
75 if (rm->atomic.op_active)
76 rds_atomic_free_op(&rm->atomic);
77 if (rm->atomic.op_rdma_mr)
78 rds_mr_put(rm->atomic.op_rdma_mr);
79}
80
81void rds_message_put(struct rds_message *rm)
82{
83 rdsdebug("put rm %p ref %d\n", rm, atomic_read(&rm->m_refcount));
84 if (atomic_read(&rm->m_refcount) == 0) {
85printk(KERN_CRIT "danger refcount zero on %p\n", rm);
86WARN_ON(1);
87 }
88 if (atomic_dec_and_test(&rm->m_refcount)) {
89 BUG_ON(!list_empty(&rm->m_sock_item));
90 BUG_ON(!list_empty(&rm->m_conn_item));
91 rds_message_purge(rm);
92
93 kfree(rm);
94 }
95}
96EXPORT_SYMBOL_GPL(rds_message_put);
97
98void rds_message_populate_header(struct rds_header *hdr, __be16 sport,
99 __be16 dport, u64 seq)
100{
101 hdr->h_flags = 0;
102 hdr->h_sport = sport;
103 hdr->h_dport = dport;
104 hdr->h_sequence = cpu_to_be64(seq);
105 hdr->h_exthdr[0] = RDS_EXTHDR_NONE;
106}
107EXPORT_SYMBOL_GPL(rds_message_populate_header);
108
109int rds_message_add_extension(struct rds_header *hdr, unsigned int type,
110 const void *data, unsigned int len)
111{
112 unsigned int ext_len = sizeof(u8) + len;
113 unsigned char *dst;
114
115 /* For now, refuse to add more than one extension header */
116 if (hdr->h_exthdr[0] != RDS_EXTHDR_NONE)
117 return 0;
118
119 if (type >= __RDS_EXTHDR_MAX || len != rds_exthdr_size[type])
120 return 0;
121
122 if (ext_len >= RDS_HEADER_EXT_SPACE)
123 return 0;
124 dst = hdr->h_exthdr;
125
126 *dst++ = type;
127 memcpy(dst, data, len);
128
129 dst[len] = RDS_EXTHDR_NONE;
130 return 1;
131}
132EXPORT_SYMBOL_GPL(rds_message_add_extension);
133
134/*
135 * If a message has extension headers, retrieve them here.
136 * Call like this:
137 *
138 * unsigned int pos = 0;
139 *
140 * while (1) {
141 * buflen = sizeof(buffer);
142 * type = rds_message_next_extension(hdr, &pos, buffer, &buflen);
143 * if (type == RDS_EXTHDR_NONE)
144 * break;
145 * ...
146 * }
147 */
148int rds_message_next_extension(struct rds_header *hdr,
149 unsigned int *pos, void *buf, unsigned int *buflen)
150{
151 unsigned int offset, ext_type, ext_len;
152 u8 *src = hdr->h_exthdr;
153
154 offset = *pos;
155 if (offset >= RDS_HEADER_EXT_SPACE)
156 goto none;
157
158 /* Get the extension type and length. For now, the
159 * length is implied by the extension type. */
160 ext_type = src[offset++];
161
162 if (ext_type == RDS_EXTHDR_NONE || ext_type >= __RDS_EXTHDR_MAX)
163 goto none;
164 ext_len = rds_exthdr_size[ext_type];
165 if (offset + ext_len > RDS_HEADER_EXT_SPACE)
166 goto none;
167
168 *pos = offset + ext_len;
169 if (ext_len < *buflen)
170 *buflen = ext_len;
171 memcpy(buf, src + offset, *buflen);
172 return ext_type;
173
174none:
175 *pos = RDS_HEADER_EXT_SPACE;
176 *buflen = 0;
177 return RDS_EXTHDR_NONE;
178}
179
180int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset)
181{
182 struct rds_ext_header_rdma_dest ext_hdr;
183
184 ext_hdr.h_rdma_rkey = cpu_to_be32(r_key);
185 ext_hdr.h_rdma_offset = cpu_to_be32(offset);
186 return rds_message_add_extension(hdr, RDS_EXTHDR_RDMA_DEST, &ext_hdr, sizeof(ext_hdr));
187}
188EXPORT_SYMBOL_GPL(rds_message_add_rdma_dest_extension);
189
190/*
191 * Each rds_message is allocated with extra space for the scatterlist entries
192 * rds ops will need. This is to minimize memory allocation count. Then, each rds op
193 * can grab SGs when initializing its part of the rds_message.
194 */
195struct rds_message *rds_message_alloc(unsigned int extra_len, gfp_t gfp)
196{
197 struct rds_message *rm;
198
199 rm = kzalloc(sizeof(struct rds_message) + extra_len, gfp);
200 if (!rm)
201 goto out;
202
203 rm->m_used_sgs = 0;
204 rm->m_total_sgs = extra_len / sizeof(struct scatterlist);
205
206 atomic_set(&rm->m_refcount, 1);
207 INIT_LIST_HEAD(&rm->m_sock_item);
208 INIT_LIST_HEAD(&rm->m_conn_item);
209 spin_lock_init(&rm->m_rs_lock);
210 init_waitqueue_head(&rm->m_flush_wait);
211
212out:
213 return rm;
214}
215
216/*
217 * RDS ops use this to grab SG entries from the rm's sg pool.
218 */
219struct scatterlist *rds_message_alloc_sgs(struct rds_message *rm, int nents)
220{
221 struct scatterlist *sg_first = (struct scatterlist *) &rm[1];
222 struct scatterlist *sg_ret;
223
224 WARN_ON(rm->m_used_sgs + nents > rm->m_total_sgs);
225 WARN_ON(!nents);
226
227 if (rm->m_used_sgs + nents > rm->m_total_sgs)
228 return NULL;
229
230 sg_ret = &sg_first[rm->m_used_sgs];
231 sg_init_table(sg_ret, nents);
232 rm->m_used_sgs += nents;
233
234 return sg_ret;
235}
236
237struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len)
238{
239 struct rds_message *rm;
240 unsigned int i;
241 int num_sgs = ceil(total_len, PAGE_SIZE);
242 int extra_bytes = num_sgs * sizeof(struct scatterlist);
243
244 rm = rds_message_alloc(extra_bytes, GFP_NOWAIT);
245 if (!rm)
246 return ERR_PTR(-ENOMEM);
247
248 set_bit(RDS_MSG_PAGEVEC, &rm->m_flags);
249 rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len);
250 rm->data.op_nents = ceil(total_len, PAGE_SIZE);
251 rm->data.op_sg = rds_message_alloc_sgs(rm, num_sgs);
252 if (!rm->data.op_sg) {
253 rds_message_put(rm);
254 return ERR_PTR(-ENOMEM);
255 }
256
257 for (i = 0; i < rm->data.op_nents; ++i) {
258 sg_set_page(&rm->data.op_sg[i],
259 virt_to_page(page_addrs[i]),
260 PAGE_SIZE, 0);
261 }
262
263 return rm;
264}
265
266int rds_message_copy_from_user(struct rds_message *rm, struct iovec *first_iov,
267 size_t total_len)
268{
269 unsigned long to_copy;
270 unsigned long iov_off;
271 unsigned long sg_off;
272 struct iovec *iov;
273 struct scatterlist *sg;
274 int ret = 0;
275
276 rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len);
277
278 /*
279 * now allocate and copy in the data payload.
280 */
281 sg = rm->data.op_sg;
282 iov = first_iov;
283 iov_off = 0;
284 sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */
285
286 while (total_len) {
287 if (!sg_page(sg)) {
288 ret = rds_page_remainder_alloc(sg, total_len,
289 GFP_HIGHUSER);
290 if (ret)
291 goto out;
292 rm->data.op_nents++;
293 sg_off = 0;
294 }
295
296 while (iov_off == iov->iov_len) {
297 iov_off = 0;
298 iov++;
299 }
300
301 to_copy = min(iov->iov_len - iov_off, sg->length - sg_off);
302 to_copy = min_t(size_t, to_copy, total_len);
303
304 rdsdebug("copying %lu bytes from user iov [%p, %zu] + %lu to "
305 "sg [%p, %u, %u] + %lu\n",
306 to_copy, iov->iov_base, iov->iov_len, iov_off,
307 (void *)sg_page(sg), sg->offset, sg->length, sg_off);
308
309 ret = rds_page_copy_from_user(sg_page(sg), sg->offset + sg_off,
310 iov->iov_base + iov_off,
311 to_copy);
312 if (ret)
313 goto out;
314
315 iov_off += to_copy;
316 total_len -= to_copy;
317 sg_off += to_copy;
318
319 if (sg_off == sg->length)
320 sg++;
321 }
322
323out:
324 return ret;
325}
326
327int rds_message_inc_copy_to_user(struct rds_incoming *inc,
328 struct iovec *first_iov, size_t size)
329{
330 struct rds_message *rm;
331 struct iovec *iov;
332 struct scatterlist *sg;
333 unsigned long to_copy;
334 unsigned long iov_off;
335 unsigned long vec_off;
336 int copied;
337 int ret;
338 u32 len;
339
340 rm = container_of(inc, struct rds_message, m_inc);
341 len = be32_to_cpu(rm->m_inc.i_hdr.h_len);
342
343 iov = first_iov;
344 iov_off = 0;
345 sg = rm->data.op_sg;
346 vec_off = 0;
347 copied = 0;
348
349 while (copied < size && copied < len) {
350 while (iov_off == iov->iov_len) {
351 iov_off = 0;
352 iov++;
353 }
354
355 to_copy = min(iov->iov_len - iov_off, sg->length - vec_off);
356 to_copy = min_t(size_t, to_copy, size - copied);
357 to_copy = min_t(unsigned long, to_copy, len - copied);
358
359 rdsdebug("copying %lu bytes to user iov [%p, %zu] + %lu to "
360 "sg [%p, %u, %u] + %lu\n",
361 to_copy, iov->iov_base, iov->iov_len, iov_off,
362 sg_page(sg), sg->offset, sg->length, vec_off);
363
364 ret = rds_page_copy_to_user(sg_page(sg), sg->offset + vec_off,
365 iov->iov_base + iov_off,
366 to_copy);
367 if (ret) {
368 copied = ret;
369 break;
370 }
371
372 iov_off += to_copy;
373 vec_off += to_copy;
374 copied += to_copy;
375
376 if (vec_off == sg->length) {
377 vec_off = 0;
378 sg++;
379 }
380 }
381
382 return copied;
383}
384
385/*
386 * If the message is still on the send queue, wait until the transport
387 * is done with it. This is particularly important for RDMA operations.
388 */
389void rds_message_wait(struct rds_message *rm)
390{
391 wait_event_interruptible(rm->m_flush_wait,
392 !test_bit(RDS_MSG_MAPPED, &rm->m_flags));
393}
394
395void rds_message_unmapped(struct rds_message *rm)
396{
397 clear_bit(RDS_MSG_MAPPED, &rm->m_flags);
398 wake_up_interruptible(&rm->m_flush_wait);
399}
400EXPORT_SYMBOL_GPL(rds_message_unmapped);
401