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 39 static 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 47 void 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 } 52 EXPORT_SYMBOL_GPL(rds_message_addref); 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->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 82 void rds_message_put(struct rds_message *rm) 83 { 84 rdsdebug("put rm %p ref %d\n", rm, atomic_read(&rm->m_refcount)); 85 if (atomic_read(&rm->m_refcount) == 0) { 86 printk(KERN_CRIT "danger refcount zero on %p\n", rm); 87 WARN_ON(1); 88 } 89 if (atomic_dec_and_test(&rm->m_refcount)) { 90 BUG_ON(!list_empty(&rm->m_sock_item)); 91 BUG_ON(!list_empty(&rm->m_conn_item)); 92 rds_message_purge(rm); 93 94 kfree(rm); 95 } 96 } 97 EXPORT_SYMBOL_GPL(rds_message_put); 98 99 void rds_message_populate_header(struct rds_header *hdr, __be16 sport, 100 __be16 dport, u64 seq) 101 { 102 hdr->h_flags = 0; 103 hdr->h_sport = sport; 104 hdr->h_dport = dport; 105 hdr->h_sequence = cpu_to_be64(seq); 106 hdr->h_exthdr[0] = RDS_EXTHDR_NONE; 107 } 108 EXPORT_SYMBOL_GPL(rds_message_populate_header); 109 110 int rds_message_add_extension(struct rds_header *hdr, unsigned int type, 111 const void *data, unsigned int len) 112 { 113 unsigned int ext_len = sizeof(u8) + len; 114 unsigned char *dst; 115 116 /* For now, refuse to add more than one extension header */ 117 if (hdr->h_exthdr[0] != RDS_EXTHDR_NONE) 118 return 0; 119 120 if (type >= __RDS_EXTHDR_MAX || len != rds_exthdr_size[type]) 121 return 0; 122 123 if (ext_len >= RDS_HEADER_EXT_SPACE) 124 return 0; 125 dst = hdr->h_exthdr; 126 127 *dst++ = type; 128 memcpy(dst, data, len); 129 130 dst[len] = RDS_EXTHDR_NONE; 131 return 1; 132 } 133 EXPORT_SYMBOL_GPL(rds_message_add_extension); 134 135 /* 136 * If a message has extension headers, retrieve them here. 137 * Call like this: 138 * 139 * unsigned int pos = 0; 140 * 141 * while (1) { 142 * buflen = sizeof(buffer); 143 * type = rds_message_next_extension(hdr, &pos, buffer, &buflen); 144 * if (type == RDS_EXTHDR_NONE) 145 * break; 146 * ... 147 * } 148 */ 149 int rds_message_next_extension(struct rds_header *hdr, 150 unsigned int *pos, void *buf, unsigned int *buflen) 151 { 152 unsigned int offset, ext_type, ext_len; 153 u8 *src = hdr->h_exthdr; 154 155 offset = *pos; 156 if (offset >= RDS_HEADER_EXT_SPACE) 157 goto none; 158 159 /* Get the extension type and length. For now, the 160 * length is implied by the extension type. */ 161 ext_type = src[offset++]; 162 163 if (ext_type == RDS_EXTHDR_NONE || ext_type >= __RDS_EXTHDR_MAX) 164 goto none; 165 ext_len = rds_exthdr_size[ext_type]; 166 if (offset + ext_len > RDS_HEADER_EXT_SPACE) 167 goto none; 168 169 *pos = offset + ext_len; 170 if (ext_len < *buflen) 171 *buflen = ext_len; 172 memcpy(buf, src + offset, *buflen); 173 return ext_type; 174 175 none: 176 *pos = RDS_HEADER_EXT_SPACE; 177 *buflen = 0; 178 return RDS_EXTHDR_NONE; 179 } 180 181 int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset) 182 { 183 struct rds_ext_header_rdma_dest ext_hdr; 184 185 ext_hdr.h_rdma_rkey = cpu_to_be32(r_key); 186 ext_hdr.h_rdma_offset = cpu_to_be32(offset); 187 return rds_message_add_extension(hdr, RDS_EXTHDR_RDMA_DEST, &ext_hdr, sizeof(ext_hdr)); 188 } 189 EXPORT_SYMBOL_GPL(rds_message_add_rdma_dest_extension); 190 191 /* 192 * Each rds_message is allocated with extra space for the scatterlist entries 193 * rds ops will need. This is to minimize memory allocation count. Then, each rds op 194 * can grab SGs when initializing its part of the rds_message. 195 */ 196 struct rds_message *rds_message_alloc(unsigned int extra_len, gfp_t gfp) 197 { 198 struct rds_message *rm; 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); 212 213 out: 214 return rm; 215 } 216 217 /* 218 * RDS ops use this to grab SG entries from the rm's sg pool. 219 */ 220 struct 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 } 237 238 struct 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 } 266 267 int rds_message_copy_from_user(struct rds_message *rm, struct iovec *first_iov, 268 size_t total_len) 269 { 270 unsigned long to_copy; 271 unsigned long iov_off; 272 unsigned long sg_off; 273 struct iovec *iov; 274 struct scatterlist *sg; 275 int ret = 0; 276 277 rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len); 278 279 /* 280 * now allocate and copy in the data payload. 281 */ 282 sg = rm->data.op_sg; 283 iov = first_iov; 284 iov_off = 0; 285 sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */ 286 287 while (total_len) { 288 if (!sg_page(sg)) { 289 ret = rds_page_remainder_alloc(sg, total_len, 290 GFP_HIGHUSER); 291 if (ret) 292 goto out; 293 rm->data.op_nents++; 294 sg_off = 0; 295 } 296 297 while (iov_off == iov->iov_len) { 298 iov_off = 0; 299 iov++; 300 } 301 302 to_copy = min(iov->iov_len - iov_off, sg->length - sg_off); 303 to_copy = min_t(size_t, to_copy, total_len); 304 305 rdsdebug("copying %lu bytes from user iov [%p, %zu] + %lu to " 306 "sg [%p, %u, %u] + %lu\n", 307 to_copy, iov->iov_base, iov->iov_len, iov_off, 308 (void *)sg_page(sg), sg->offset, sg->length, sg_off); 309 310 ret = rds_page_copy_from_user(sg_page(sg), sg->offset + sg_off, 311 iov->iov_base + iov_off, 312 to_copy); 313 if (ret) 314 goto out; 315 316 iov_off += to_copy; 317 total_len -= to_copy; 318 sg_off += to_copy; 319 320 if (sg_off == sg->length) 321 sg++; 322 } 323 324 out: 325 return ret; 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->data.op_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_interruptible(rm->m_flush_wait, 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 wake_up_interruptible(&rm->m_flush_wait); 400 } 401 EXPORT_SYMBOL_GPL(rds_message_unmapped); 402 403