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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#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[RDS_EXTHDR_NPATHS] = sizeof(u16),
45[RDS_EXTHDR_GEN_NUM] = sizeof(u32),
46};
47
48
49void rds_message_addref(struct rds_message *rm)
50{
51 rdsdebug("addref rm %p ref %d\n", rm, atomic_read(&rm->m_refcount));
52 atomic_inc(&rm->m_refcount);
53}
54EXPORT_SYMBOL_GPL(rds_message_addref);
55
56/*
57 * This relies on dma_map_sg() not touching sg[].page during merging.
58 */
59static void rds_message_purge(struct rds_message *rm)
60{
61 unsigned long i;
62
63 if (unlikely(test_bit(RDS_MSG_PAGEVEC, &rm->m_flags)))
64 return;
65
66 for (i = 0; i < rm->data.op_nents; i++) {
67 rdsdebug("putting data page %p\n", (void *)sg_page(&rm->data.op_sg[i]));
68 /* XXX will have to put_page for page refs */
69 __free_page(sg_page(&rm->data.op_sg[i]));
70 }
71 rm->data.op_nents = 0;
72
73 if (rm->rdma.op_active)
74 rds_rdma_free_op(&rm->rdma);
75 if (rm->rdma.op_rdma_mr)
76 rds_mr_put(rm->rdma.op_rdma_mr);
77
78 if (rm->atomic.op_active)
79 rds_atomic_free_op(&rm->atomic);
80 if (rm->atomic.op_rdma_mr)
81 rds_mr_put(rm->atomic.op_rdma_mr);
82}
83
84void rds_message_put(struct rds_message *rm)
85{
86 rdsdebug("put rm %p ref %d\n", rm, atomic_read(&rm->m_refcount));
87 WARN(!atomic_read(&rm->m_refcount), "danger refcount zero on %p\n", rm);
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 if (extra_len > KMALLOC_MAX_SIZE - sizeof(struct rds_message))
200 return NULL;
201
202 rm = kzalloc(sizeof(struct rds_message) + extra_len, gfp);
203 if (!rm)
204 goto out;
205
206 rm->m_used_sgs = 0;
207 rm->m_total_sgs = extra_len / sizeof(struct scatterlist);
208
209 atomic_set(&rm->m_refcount, 1);
210 INIT_LIST_HEAD(&rm->m_sock_item);
211 INIT_LIST_HEAD(&rm->m_conn_item);
212 spin_lock_init(&rm->m_rs_lock);
213 init_waitqueue_head(&rm->m_flush_wait);
214
215out:
216 return rm;
217}
218
219/*
220 * RDS ops use this to grab SG entries from the rm's sg pool.
221 */
222struct scatterlist *rds_message_alloc_sgs(struct rds_message *rm, int nents)
223{
224 struct scatterlist *sg_first = (struct scatterlist *) &rm[1];
225 struct scatterlist *sg_ret;
226
227 WARN_ON(rm->m_used_sgs + nents > rm->m_total_sgs);
228 WARN_ON(!nents);
229
230 if (rm->m_used_sgs + nents > rm->m_total_sgs)
231 return NULL;
232
233 sg_ret = &sg_first[rm->m_used_sgs];
234 sg_init_table(sg_ret, nents);
235 rm->m_used_sgs += nents;
236
237 return sg_ret;
238}
239
240struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len)
241{
242 struct rds_message *rm;
243 unsigned int i;
244 int num_sgs = ceil(total_len, PAGE_SIZE);
245 int extra_bytes = num_sgs * sizeof(struct scatterlist);
246
247 rm = rds_message_alloc(extra_bytes, GFP_NOWAIT);
248 if (!rm)
249 return ERR_PTR(-ENOMEM);
250
251 set_bit(RDS_MSG_PAGEVEC, &rm->m_flags);
252 rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len);
253 rm->data.op_nents = ceil(total_len, PAGE_SIZE);
254 rm->data.op_sg = rds_message_alloc_sgs(rm, num_sgs);
255 if (!rm->data.op_sg) {
256 rds_message_put(rm);
257 return ERR_PTR(-ENOMEM);
258 }
259
260 for (i = 0; i < rm->data.op_nents; ++i) {
261 sg_set_page(&rm->data.op_sg[i],
262 virt_to_page(page_addrs[i]),
263 PAGE_SIZE, 0);
264 }
265
266 return rm;
267}
268
269int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from)
270{
271 unsigned long to_copy, nbytes;
272 unsigned long sg_off;
273 struct scatterlist *sg;
274 int ret = 0;
275
276 rm->m_inc.i_hdr.h_len = cpu_to_be32(iov_iter_count(from));
277
278 /*
279 * now allocate and copy in the data payload.
280 */
281 sg = rm->data.op_sg;
282 sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */
283
284 while (iov_iter_count(from)) {
285 if (!sg_page(sg)) {
286 ret = rds_page_remainder_alloc(sg, iov_iter_count(from),
287 GFP_HIGHUSER);
288 if (ret)
289 return ret;
290 rm->data.op_nents++;
291 sg_off = 0;
292 }
293
294 to_copy = min_t(unsigned long, iov_iter_count(from),
295 sg->length - sg_off);
296
297 rds_stats_add(s_copy_from_user, to_copy);
298 nbytes = copy_page_from_iter(sg_page(sg), sg->offset + sg_off,
299 to_copy, from);
300 if (nbytes != to_copy)
301 return -EFAULT;
302
303 sg_off += to_copy;
304
305 if (sg_off == sg->length)
306 sg++;
307 }
308
309 return ret;
310}
311
312int rds_message_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to)
313{
314 struct rds_message *rm;
315 struct scatterlist *sg;
316 unsigned long to_copy;
317 unsigned long vec_off;
318 int copied;
319 int ret;
320 u32 len;
321
322 rm = container_of(inc, struct rds_message, m_inc);
323 len = be32_to_cpu(rm->m_inc.i_hdr.h_len);
324
325 sg = rm->data.op_sg;
326 vec_off = 0;
327 copied = 0;
328
329 while (iov_iter_count(to) && copied < len) {
330 to_copy = min_t(unsigned long, iov_iter_count(to),
331 sg->length - vec_off);
332 to_copy = min_t(unsigned long, to_copy, len - copied);
333
334 rds_stats_add(s_copy_to_user, to_copy);
335 ret = copy_page_to_iter(sg_page(sg), sg->offset + vec_off,
336 to_copy, to);
337 if (ret != to_copy)
338 return -EFAULT;
339
340 vec_off += to_copy;
341 copied += to_copy;
342
343 if (vec_off == sg->length) {
344 vec_off = 0;
345 sg++;
346 }
347 }
348
349 return copied;
350}
351
352/*
353 * If the message is still on the send queue, wait until the transport
354 * is done with it. This is particularly important for RDMA operations.
355 */
356void rds_message_wait(struct rds_message *rm)
357{
358 wait_event_interruptible(rm->m_flush_wait,
359 !test_bit(RDS_MSG_MAPPED, &rm->m_flags));
360}
361
362void rds_message_unmapped(struct rds_message *rm)
363{
364 clear_bit(RDS_MSG_MAPPED, &rm->m_flags);
365 wake_up_interruptible(&rm->m_flush_wait);
366}
367EXPORT_SYMBOL_GPL(rds_message_unmapped);
368