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 35 #include "rds.h" 36 #include "rdma.h" 37 38 static DECLARE_WAIT_QUEUE_HEAD(rds_message_flush_waitq); 39 40 static unsigned int rds_exthdr_size[__RDS_EXTHDR_MAX] = { 41 [RDS_EXTHDR_NONE] = 0, 42 [RDS_EXTHDR_VERSION] = sizeof(struct rds_ext_header_version), 43 [RDS_EXTHDR_RDMA] = sizeof(struct rds_ext_header_rdma), 44 [RDS_EXTHDR_RDMA_DEST] = sizeof(struct rds_ext_header_rdma_dest), 45 }; 46 47 48 void rds_message_addref(struct rds_message *rm) 49 { 50 rdsdebug("addref rm %p ref %d\n", rm, atomic_read(&rm->m_refcount)); 51 atomic_inc(&rm->m_refcount); 52 } 53 54 /* 55 * This relies on dma_map_sg() not touching sg[].page during merging. 56 */ 57 static 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->m_nents; i++) { 65 rdsdebug("putting data page %p\n", (void *)sg_page(&rm->m_sg[i])); 66 /* XXX will have to put_page for page refs */ 67 __free_page(sg_page(&rm->m_sg[i])); 68 } 69 rm->m_nents = 0; 70 71 if (rm->m_rdma_op) 72 rds_rdma_free_op(rm->m_rdma_op); 73 if (rm->m_rdma_mr) 74 rds_mr_put(rm->m_rdma_mr); 75 } 76 77 void rds_message_inc_purge(struct rds_incoming *inc) 78 { 79 struct rds_message *rm = container_of(inc, struct rds_message, m_inc); 80 rds_message_purge(rm); 81 } 82 83 void rds_message_put(struct rds_message *rm) 84 { 85 rdsdebug("put rm %p ref %d\n", rm, atomic_read(&rm->m_refcount)); 86 87 if (atomic_dec_and_test(&rm->m_refcount)) { 88 BUG_ON(!list_empty(&rm->m_sock_item)); 89 BUG_ON(!list_empty(&rm->m_conn_item)); 90 rds_message_purge(rm); 91 92 kfree(rm); 93 } 94 } 95 96 void rds_message_inc_free(struct rds_incoming *inc) 97 { 98 struct rds_message *rm = container_of(inc, struct rds_message, m_inc); 99 rds_message_put(rm); 100 } 101 102 void rds_message_populate_header(struct rds_header *hdr, __be16 sport, 103 __be16 dport, u64 seq) 104 { 105 hdr->h_flags = 0; 106 hdr->h_sport = sport; 107 hdr->h_dport = dport; 108 hdr->h_sequence = cpu_to_be64(seq); 109 hdr->h_exthdr[0] = RDS_EXTHDR_NONE; 110 } 111 112 int rds_message_add_extension(struct rds_header *hdr, 113 unsigned int type, const void *data, unsigned int len) 114 { 115 unsigned int ext_len = sizeof(u8) + len; 116 unsigned char *dst; 117 118 /* For now, refuse to add more than one extension header */ 119 if (hdr->h_exthdr[0] != RDS_EXTHDR_NONE) 120 return 0; 121 122 if (type >= __RDS_EXTHDR_MAX 123 || len != rds_exthdr_size[type]) 124 return 0; 125 126 if (ext_len >= RDS_HEADER_EXT_SPACE) 127 return 0; 128 dst = hdr->h_exthdr; 129 130 *dst++ = type; 131 memcpy(dst, data, len); 132 133 dst[len] = RDS_EXTHDR_NONE; 134 return 1; 135 } 136 137 /* 138 * If a message has extension headers, retrieve them here. 139 * Call like this: 140 * 141 * unsigned int pos = 0; 142 * 143 * while (1) { 144 * buflen = sizeof(buffer); 145 * type = rds_message_next_extension(hdr, &pos, buffer, &buflen); 146 * if (type == RDS_EXTHDR_NONE) 147 * break; 148 * ... 149 * } 150 */ 151 int rds_message_next_extension(struct rds_header *hdr, 152 unsigned int *pos, void *buf, unsigned int *buflen) 153 { 154 unsigned int offset, ext_type, ext_len; 155 u8 *src = hdr->h_exthdr; 156 157 offset = *pos; 158 if (offset >= RDS_HEADER_EXT_SPACE) 159 goto none; 160 161 /* Get the extension type and length. For now, the 162 * length is implied by the extension type. */ 163 ext_type = src[offset++]; 164 165 if (ext_type == RDS_EXTHDR_NONE || ext_type >= __RDS_EXTHDR_MAX) 166 goto none; 167 ext_len = rds_exthdr_size[ext_type]; 168 if (offset + ext_len > RDS_HEADER_EXT_SPACE) 169 goto none; 170 171 *pos = offset + ext_len; 172 if (ext_len < *buflen) 173 *buflen = ext_len; 174 memcpy(buf, src + offset, *buflen); 175 return ext_type; 176 177 none: 178 *pos = RDS_HEADER_EXT_SPACE; 179 *buflen = 0; 180 return RDS_EXTHDR_NONE; 181 } 182 183 int rds_message_add_version_extension(struct rds_header *hdr, unsigned int version) 184 { 185 struct rds_ext_header_version ext_hdr; 186 187 ext_hdr.h_version = cpu_to_be32(version); 188 return rds_message_add_extension(hdr, RDS_EXTHDR_VERSION, &ext_hdr, sizeof(ext_hdr)); 189 } 190 191 int rds_message_get_version_extension(struct rds_header *hdr, unsigned int *version) 192 { 193 struct rds_ext_header_version ext_hdr; 194 unsigned int pos = 0, len = sizeof(ext_hdr); 195 196 /* We assume the version extension is the only one present */ 197 if (rds_message_next_extension(hdr, &pos, &ext_hdr, &len) != RDS_EXTHDR_VERSION) 198 return 0; 199 *version = be32_to_cpu(ext_hdr.h_version); 200 return 1; 201 } 202 203 int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset) 204 { 205 struct rds_ext_header_rdma_dest ext_hdr; 206 207 ext_hdr.h_rdma_rkey = cpu_to_be32(r_key); 208 ext_hdr.h_rdma_offset = cpu_to_be32(offset); 209 return rds_message_add_extension(hdr, RDS_EXTHDR_RDMA_DEST, &ext_hdr, sizeof(ext_hdr)); 210 } 211 212 struct rds_message *rds_message_alloc(unsigned int nents, gfp_t gfp) 213 { 214 struct rds_message *rm; 215 216 rm = kzalloc(sizeof(struct rds_message) + 217 (nents * sizeof(struct scatterlist)), gfp); 218 if (!rm) 219 goto out; 220 221 if (nents) 222 sg_init_table(rm->m_sg, nents); 223 atomic_set(&rm->m_refcount, 1); 224 INIT_LIST_HEAD(&rm->m_sock_item); 225 INIT_LIST_HEAD(&rm->m_conn_item); 226 spin_lock_init(&rm->m_rs_lock); 227 228 out: 229 return rm; 230 } 231 232 struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len) 233 { 234 struct rds_message *rm; 235 unsigned int i; 236 237 rm = rds_message_alloc(ceil(total_len, PAGE_SIZE), GFP_KERNEL); 238 if (rm == NULL) 239 return ERR_PTR(-ENOMEM); 240 241 set_bit(RDS_MSG_PAGEVEC, &rm->m_flags); 242 rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len); 243 rm->m_nents = ceil(total_len, PAGE_SIZE); 244 245 for (i = 0; i < rm->m_nents; ++i) { 246 sg_set_page(&rm->m_sg[i], 247 virt_to_page(page_addrs[i]), 248 PAGE_SIZE, 0); 249 } 250 251 return rm; 252 } 253 254 struct rds_message *rds_message_copy_from_user(struct iovec *first_iov, 255 size_t total_len) 256 { 257 unsigned long to_copy; 258 unsigned long iov_off; 259 unsigned long sg_off; 260 struct rds_message *rm; 261 struct iovec *iov; 262 struct scatterlist *sg; 263 int ret; 264 265 rm = rds_message_alloc(ceil(total_len, PAGE_SIZE), GFP_KERNEL); 266 if (rm == NULL) { 267 ret = -ENOMEM; 268 goto out; 269 } 270 271 rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len); 272 273 /* 274 * now allocate and copy in the data payload. 275 */ 276 sg = rm->m_sg; 277 iov = first_iov; 278 iov_off = 0; 279 sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */ 280 281 while (total_len) { 282 if (sg_page(sg) == NULL) { 283 ret = rds_page_remainder_alloc(sg, total_len, 284 GFP_HIGHUSER); 285 if (ret) 286 goto out; 287 rm->m_nents++; 288 sg_off = 0; 289 } 290 291 while (iov_off == iov->iov_len) { 292 iov_off = 0; 293 iov++; 294 } 295 296 to_copy = min(iov->iov_len - iov_off, sg->length - sg_off); 297 to_copy = min_t(size_t, to_copy, total_len); 298 299 rdsdebug("copying %lu bytes from user iov [%p, %zu] + %lu to " 300 "sg [%p, %u, %u] + %lu\n", 301 to_copy, iov->iov_base, iov->iov_len, iov_off, 302 (void *)sg_page(sg), sg->offset, sg->length, sg_off); 303 304 ret = rds_page_copy_from_user(sg_page(sg), sg->offset + sg_off, 305 iov->iov_base + iov_off, 306 to_copy); 307 if (ret) 308 goto out; 309 310 iov_off += to_copy; 311 total_len -= to_copy; 312 sg_off += to_copy; 313 314 if (sg_off == sg->length) 315 sg++; 316 } 317 318 ret = 0; 319 out: 320 if (ret) { 321 if (rm) 322 rds_message_put(rm); 323 rm = ERR_PTR(ret); 324 } 325 return rm; 326 } 327 328 int rds_message_inc_copy_to_user(struct rds_incoming *inc, 329 struct iovec *first_iov, size_t size) 330 { 331 struct rds_message *rm; 332 struct iovec *iov; 333 struct scatterlist *sg; 334 unsigned long to_copy; 335 unsigned long iov_off; 336 unsigned long vec_off; 337 int copied; 338 int ret; 339 u32 len; 340 341 rm = container_of(inc, struct rds_message, m_inc); 342 len = be32_to_cpu(rm->m_inc.i_hdr.h_len); 343 344 iov = first_iov; 345 iov_off = 0; 346 sg = rm->m_sg; 347 vec_off = 0; 348 copied = 0; 349 350 while (copied < size && copied < len) { 351 while (iov_off == iov->iov_len) { 352 iov_off = 0; 353 iov++; 354 } 355 356 to_copy = min(iov->iov_len - iov_off, sg->length - vec_off); 357 to_copy = min_t(size_t, to_copy, size - copied); 358 to_copy = min_t(unsigned long, to_copy, len - copied); 359 360 rdsdebug("copying %lu bytes to user iov [%p, %zu] + %lu to " 361 "sg [%p, %u, %u] + %lu\n", 362 to_copy, iov->iov_base, iov->iov_len, iov_off, 363 sg_page(sg), sg->offset, sg->length, vec_off); 364 365 ret = rds_page_copy_to_user(sg_page(sg), sg->offset + vec_off, 366 iov->iov_base + iov_off, 367 to_copy); 368 if (ret) { 369 copied = ret; 370 break; 371 } 372 373 iov_off += to_copy; 374 vec_off += to_copy; 375 copied += to_copy; 376 377 if (vec_off == sg->length) { 378 vec_off = 0; 379 sg++; 380 } 381 } 382 383 return copied; 384 } 385 386 /* 387 * If the message is still on the send queue, wait until the transport 388 * is done with it. This is particularly important for RDMA operations. 389 */ 390 void rds_message_wait(struct rds_message *rm) 391 { 392 wait_event(rds_message_flush_waitq, 393 !test_bit(RDS_MSG_MAPPED, &rm->m_flags)); 394 } 395 396 void rds_message_unmapped(struct rds_message *rm) 397 { 398 clear_bit(RDS_MSG_MAPPED, &rm->m_flags); 399 if (waitqueue_active(&rds_message_flush_waitq)) 400 wake_up(&rds_message_flush_waitq); 401 } 402 403