Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/net/sunrpc/xdr.c |
| 3 | * |
| 4 | * Generic XDR support. |
| 5 | * |
| 6 | * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> |
| 7 | */ |
| 8 | |
Chuck Lever | a246b01 | 2005-08-11 16:25:23 -0400 | [diff] [blame] | 9 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/types.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/string.h> |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/pagemap.h> |
| 14 | #include <linux/errno.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/sunrpc/xdr.h> |
| 16 | #include <linux/sunrpc/msg_prot.h> |
| 17 | |
| 18 | /* |
| 19 | * XDR functions for basic NFS types |
| 20 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 21 | __be32 * |
| 22 | xdr_encode_netobj(__be32 *p, const struct xdr_netobj *obj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | { |
| 24 | unsigned int quadlen = XDR_QUADLEN(obj->len); |
| 25 | |
| 26 | p[quadlen] = 0; /* zero trailing bytes */ |
| 27 | *p++ = htonl(obj->len); |
| 28 | memcpy(p, obj->data, obj->len); |
| 29 | return p + XDR_QUADLEN(obj->len); |
| 30 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 31 | EXPORT_SYMBOL(xdr_encode_netobj); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 33 | __be32 * |
| 34 | xdr_decode_netobj(__be32 *p, struct xdr_netobj *obj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | { |
| 36 | unsigned int len; |
| 37 | |
| 38 | if ((len = ntohl(*p++)) > XDR_MAX_NETOBJ) |
| 39 | return NULL; |
| 40 | obj->len = len; |
| 41 | obj->data = (u8 *) p; |
| 42 | return p + XDR_QUADLEN(len); |
| 43 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 44 | EXPORT_SYMBOL(xdr_decode_netobj); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | |
| 46 | /** |
| 47 | * xdr_encode_opaque_fixed - Encode fixed length opaque data |
Pavel Pisa | 4dc3b16 | 2005-05-01 08:59:25 -0700 | [diff] [blame] | 48 | * @p: pointer to current position in XDR buffer. |
| 49 | * @ptr: pointer to data to encode (or NULL) |
| 50 | * @nbytes: size of data. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | * |
| 52 | * Copy the array of data of length nbytes at ptr to the XDR buffer |
| 53 | * at position p, then align to the next 32-bit boundary by padding |
| 54 | * with zero bytes (see RFC1832). |
| 55 | * Note: if ptr is NULL, only the padding is performed. |
| 56 | * |
| 57 | * Returns the updated current XDR buffer position |
| 58 | * |
| 59 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 60 | __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int nbytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | { |
| 62 | if (likely(nbytes != 0)) { |
| 63 | unsigned int quadlen = XDR_QUADLEN(nbytes); |
| 64 | unsigned int padding = (quadlen << 2) - nbytes; |
| 65 | |
| 66 | if (ptr != NULL) |
| 67 | memcpy(p, ptr, nbytes); |
| 68 | if (padding != 0) |
| 69 | memset((char *)p + nbytes, 0, padding); |
| 70 | p += quadlen; |
| 71 | } |
| 72 | return p; |
| 73 | } |
| 74 | EXPORT_SYMBOL(xdr_encode_opaque_fixed); |
| 75 | |
| 76 | /** |
| 77 | * xdr_encode_opaque - Encode variable length opaque data |
Pavel Pisa | 4dc3b16 | 2005-05-01 08:59:25 -0700 | [diff] [blame] | 78 | * @p: pointer to current position in XDR buffer. |
| 79 | * @ptr: pointer to data to encode (or NULL) |
| 80 | * @nbytes: size of data. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | * |
| 82 | * Returns the updated current XDR buffer position |
| 83 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 84 | __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int nbytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | { |
| 86 | *p++ = htonl(nbytes); |
| 87 | return xdr_encode_opaque_fixed(p, ptr, nbytes); |
| 88 | } |
| 89 | EXPORT_SYMBOL(xdr_encode_opaque); |
| 90 | |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 91 | __be32 * |
| 92 | xdr_encode_string(__be32 *p, const char *string) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | { |
| 94 | return xdr_encode_array(p, string, strlen(string)); |
| 95 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 96 | EXPORT_SYMBOL(xdr_encode_string); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 98 | __be32 * |
| 99 | xdr_decode_string_inplace(__be32 *p, char **sp, int *lenp, int maxlen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | { |
| 101 | unsigned int len; |
| 102 | |
| 103 | if ((len = ntohl(*p++)) > maxlen) |
| 104 | return NULL; |
| 105 | *lenp = len; |
| 106 | *sp = (char *) p; |
| 107 | return p + XDR_QUADLEN(len); |
| 108 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 109 | EXPORT_SYMBOL(xdr_decode_string_inplace); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | |
| 111 | void |
| 112 | xdr_encode_pages(struct xdr_buf *xdr, struct page **pages, unsigned int base, |
| 113 | unsigned int len) |
| 114 | { |
| 115 | struct kvec *tail = xdr->tail; |
| 116 | u32 *p; |
| 117 | |
| 118 | xdr->pages = pages; |
| 119 | xdr->page_base = base; |
| 120 | xdr->page_len = len; |
| 121 | |
| 122 | p = (u32 *)xdr->head[0].iov_base + XDR_QUADLEN(xdr->head[0].iov_len); |
| 123 | tail->iov_base = p; |
| 124 | tail->iov_len = 0; |
| 125 | |
| 126 | if (len & 3) { |
| 127 | unsigned int pad = 4 - (len & 3); |
| 128 | |
| 129 | *p = 0; |
| 130 | tail->iov_base = (char *)p + (len & 3); |
| 131 | tail->iov_len = pad; |
| 132 | len += pad; |
| 133 | } |
| 134 | xdr->buflen += len; |
| 135 | xdr->len += len; |
| 136 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 137 | EXPORT_SYMBOL(xdr_encode_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | |
| 139 | void |
| 140 | xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset, |
| 141 | struct page **pages, unsigned int base, unsigned int len) |
| 142 | { |
| 143 | struct kvec *head = xdr->head; |
| 144 | struct kvec *tail = xdr->tail; |
| 145 | char *buf = (char *)head->iov_base; |
| 146 | unsigned int buflen = head->iov_len; |
| 147 | |
| 148 | head->iov_len = offset; |
| 149 | |
| 150 | xdr->pages = pages; |
| 151 | xdr->page_base = base; |
| 152 | xdr->page_len = len; |
| 153 | |
| 154 | tail->iov_base = buf + offset; |
| 155 | tail->iov_len = buflen - offset; |
| 156 | |
| 157 | xdr->buflen += len; |
| 158 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 159 | EXPORT_SYMBOL(xdr_inline_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 161 | /* |
| 162 | * Helper routines for doing 'memmove' like operations on a struct xdr_buf |
| 163 | * |
| 164 | * _shift_data_right_pages |
| 165 | * @pages: vector of pages containing both the source and dest memory area. |
| 166 | * @pgto_base: page vector address of destination |
| 167 | * @pgfrom_base: page vector address of source |
| 168 | * @len: number of bytes to copy |
| 169 | * |
| 170 | * Note: the addresses pgto_base and pgfrom_base are both calculated in |
| 171 | * the same way: |
| 172 | * if a memory area starts at byte 'base' in page 'pages[i]', |
| 173 | * then its address is given as (i << PAGE_CACHE_SHIFT) + base |
| 174 | * Also note: pgfrom_base must be < pgto_base, but the memory areas |
| 175 | * they point to may overlap. |
| 176 | */ |
| 177 | static void |
| 178 | _shift_data_right_pages(struct page **pages, size_t pgto_base, |
| 179 | size_t pgfrom_base, size_t len) |
| 180 | { |
| 181 | struct page **pgfrom, **pgto; |
| 182 | char *vfrom, *vto; |
| 183 | size_t copy; |
| 184 | |
| 185 | BUG_ON(pgto_base <= pgfrom_base); |
| 186 | |
| 187 | pgto_base += len; |
| 188 | pgfrom_base += len; |
| 189 | |
| 190 | pgto = pages + (pgto_base >> PAGE_CACHE_SHIFT); |
| 191 | pgfrom = pages + (pgfrom_base >> PAGE_CACHE_SHIFT); |
| 192 | |
| 193 | pgto_base &= ~PAGE_CACHE_MASK; |
| 194 | pgfrom_base &= ~PAGE_CACHE_MASK; |
| 195 | |
| 196 | do { |
| 197 | /* Are any pointers crossing a page boundary? */ |
| 198 | if (pgto_base == 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | pgto_base = PAGE_CACHE_SIZE; |
| 200 | pgto--; |
| 201 | } |
| 202 | if (pgfrom_base == 0) { |
| 203 | pgfrom_base = PAGE_CACHE_SIZE; |
| 204 | pgfrom--; |
| 205 | } |
| 206 | |
| 207 | copy = len; |
| 208 | if (copy > pgto_base) |
| 209 | copy = pgto_base; |
| 210 | if (copy > pgfrom_base) |
| 211 | copy = pgfrom_base; |
| 212 | pgto_base -= copy; |
| 213 | pgfrom_base -= copy; |
| 214 | |
| 215 | vto = kmap_atomic(*pgto, KM_USER0); |
| 216 | vfrom = kmap_atomic(*pgfrom, KM_USER1); |
| 217 | memmove(vto + pgto_base, vfrom + pgfrom_base, copy); |
Trond Myklebust | bce3481 | 2006-07-05 13:17:12 -0400 | [diff] [blame] | 218 | flush_dcache_page(*pgto); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | kunmap_atomic(vfrom, KM_USER1); |
| 220 | kunmap_atomic(vto, KM_USER0); |
| 221 | |
| 222 | } while ((len -= copy) != 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | } |
| 224 | |
| 225 | /* |
| 226 | * _copy_to_pages |
| 227 | * @pages: array of pages |
| 228 | * @pgbase: page vector address of destination |
| 229 | * @p: pointer to source data |
| 230 | * @len: length |
| 231 | * |
| 232 | * Copies data from an arbitrary memory location into an array of pages |
| 233 | * The copy is assumed to be non-overlapping. |
| 234 | */ |
| 235 | static void |
| 236 | _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len) |
| 237 | { |
| 238 | struct page **pgto; |
| 239 | char *vto; |
| 240 | size_t copy; |
| 241 | |
| 242 | pgto = pages + (pgbase >> PAGE_CACHE_SHIFT); |
| 243 | pgbase &= ~PAGE_CACHE_MASK; |
| 244 | |
| 245 | do { |
| 246 | copy = PAGE_CACHE_SIZE - pgbase; |
| 247 | if (copy > len) |
| 248 | copy = len; |
| 249 | |
| 250 | vto = kmap_atomic(*pgto, KM_USER0); |
| 251 | memcpy(vto + pgbase, p, copy); |
| 252 | kunmap_atomic(vto, KM_USER0); |
| 253 | |
| 254 | pgbase += copy; |
| 255 | if (pgbase == PAGE_CACHE_SIZE) { |
| 256 | flush_dcache_page(*pgto); |
| 257 | pgbase = 0; |
| 258 | pgto++; |
| 259 | } |
| 260 | p += copy; |
| 261 | |
| 262 | } while ((len -= copy) != 0); |
| 263 | flush_dcache_page(*pgto); |
| 264 | } |
| 265 | |
| 266 | /* |
| 267 | * _copy_from_pages |
| 268 | * @p: pointer to destination |
| 269 | * @pages: array of pages |
| 270 | * @pgbase: offset of source data |
| 271 | * @len: length |
| 272 | * |
| 273 | * Copies data into an arbitrary memory location from an array of pages |
| 274 | * The copy is assumed to be non-overlapping. |
| 275 | */ |
| 276 | static void |
| 277 | _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len) |
| 278 | { |
| 279 | struct page **pgfrom; |
| 280 | char *vfrom; |
| 281 | size_t copy; |
| 282 | |
| 283 | pgfrom = pages + (pgbase >> PAGE_CACHE_SHIFT); |
| 284 | pgbase &= ~PAGE_CACHE_MASK; |
| 285 | |
| 286 | do { |
| 287 | copy = PAGE_CACHE_SIZE - pgbase; |
| 288 | if (copy > len) |
| 289 | copy = len; |
| 290 | |
| 291 | vfrom = kmap_atomic(*pgfrom, KM_USER0); |
| 292 | memcpy(p, vfrom + pgbase, copy); |
| 293 | kunmap_atomic(vfrom, KM_USER0); |
| 294 | |
| 295 | pgbase += copy; |
| 296 | if (pgbase == PAGE_CACHE_SIZE) { |
| 297 | pgbase = 0; |
| 298 | pgfrom++; |
| 299 | } |
| 300 | p += copy; |
| 301 | |
| 302 | } while ((len -= copy) != 0); |
| 303 | } |
| 304 | |
| 305 | /* |
| 306 | * xdr_shrink_bufhead |
| 307 | * @buf: xdr_buf |
| 308 | * @len: bytes to remove from buf->head[0] |
| 309 | * |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 310 | * Shrinks XDR buffer's header kvec buf->head[0] by |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | * 'len' bytes. The extra data is not lost, but is instead |
| 312 | * moved into the inlined pages and/or the tail. |
| 313 | */ |
| 314 | static void |
| 315 | xdr_shrink_bufhead(struct xdr_buf *buf, size_t len) |
| 316 | { |
| 317 | struct kvec *head, *tail; |
| 318 | size_t copy, offs; |
| 319 | unsigned int pglen = buf->page_len; |
| 320 | |
| 321 | tail = buf->tail; |
| 322 | head = buf->head; |
| 323 | BUG_ON (len > head->iov_len); |
| 324 | |
| 325 | /* Shift the tail first */ |
| 326 | if (tail->iov_len != 0) { |
| 327 | if (tail->iov_len > len) { |
| 328 | copy = tail->iov_len - len; |
| 329 | memmove((char *)tail->iov_base + len, |
| 330 | tail->iov_base, copy); |
| 331 | } |
| 332 | /* Copy from the inlined pages into the tail */ |
| 333 | copy = len; |
| 334 | if (copy > pglen) |
| 335 | copy = pglen; |
| 336 | offs = len - copy; |
| 337 | if (offs >= tail->iov_len) |
| 338 | copy = 0; |
| 339 | else if (copy > tail->iov_len - offs) |
| 340 | copy = tail->iov_len - offs; |
| 341 | if (copy != 0) |
| 342 | _copy_from_pages((char *)tail->iov_base + offs, |
| 343 | buf->pages, |
| 344 | buf->page_base + pglen + offs - len, |
| 345 | copy); |
| 346 | /* Do we also need to copy data from the head into the tail ? */ |
| 347 | if (len > pglen) { |
| 348 | offs = copy = len - pglen; |
| 349 | if (copy > tail->iov_len) |
| 350 | copy = tail->iov_len; |
| 351 | memcpy(tail->iov_base, |
| 352 | (char *)head->iov_base + |
| 353 | head->iov_len - offs, |
| 354 | copy); |
| 355 | } |
| 356 | } |
| 357 | /* Now handle pages */ |
| 358 | if (pglen != 0) { |
| 359 | if (pglen > len) |
| 360 | _shift_data_right_pages(buf->pages, |
| 361 | buf->page_base + len, |
| 362 | buf->page_base, |
| 363 | pglen - len); |
| 364 | copy = len; |
| 365 | if (len > pglen) |
| 366 | copy = pglen; |
| 367 | _copy_to_pages(buf->pages, buf->page_base, |
| 368 | (char *)head->iov_base + head->iov_len - len, |
| 369 | copy); |
| 370 | } |
| 371 | head->iov_len -= len; |
| 372 | buf->buflen -= len; |
| 373 | /* Have we truncated the message? */ |
| 374 | if (buf->len > buf->buflen) |
| 375 | buf->len = buf->buflen; |
| 376 | } |
| 377 | |
| 378 | /* |
| 379 | * xdr_shrink_pagelen |
| 380 | * @buf: xdr_buf |
| 381 | * @len: bytes to remove from buf->pages |
| 382 | * |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 383 | * Shrinks XDR buffer's page array buf->pages by |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 384 | * 'len' bytes. The extra data is not lost, but is instead |
| 385 | * moved into the tail. |
| 386 | */ |
| 387 | static void |
| 388 | xdr_shrink_pagelen(struct xdr_buf *buf, size_t len) |
| 389 | { |
| 390 | struct kvec *tail; |
| 391 | size_t copy; |
| 392 | char *p; |
| 393 | unsigned int pglen = buf->page_len; |
| 394 | |
| 395 | tail = buf->tail; |
| 396 | BUG_ON (len > pglen); |
| 397 | |
| 398 | /* Shift the tail first */ |
| 399 | if (tail->iov_len != 0) { |
| 400 | p = (char *)tail->iov_base + len; |
| 401 | if (tail->iov_len > len) { |
| 402 | copy = tail->iov_len - len; |
| 403 | memmove(p, tail->iov_base, copy); |
| 404 | } else |
| 405 | buf->buflen -= len; |
| 406 | /* Copy from the inlined pages into the tail */ |
| 407 | copy = len; |
| 408 | if (copy > tail->iov_len) |
| 409 | copy = tail->iov_len; |
| 410 | _copy_from_pages((char *)tail->iov_base, |
| 411 | buf->pages, buf->page_base + pglen - len, |
| 412 | copy); |
| 413 | } |
| 414 | buf->page_len -= len; |
| 415 | buf->buflen -= len; |
| 416 | /* Have we truncated the message? */ |
| 417 | if (buf->len > buf->buflen) |
| 418 | buf->len = buf->buflen; |
| 419 | } |
| 420 | |
| 421 | void |
| 422 | xdr_shift_buf(struct xdr_buf *buf, size_t len) |
| 423 | { |
| 424 | xdr_shrink_bufhead(buf, len); |
| 425 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 426 | EXPORT_SYMBOL(xdr_shift_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | |
| 428 | /** |
| 429 | * xdr_init_encode - Initialize a struct xdr_stream for sending data. |
| 430 | * @xdr: pointer to xdr_stream struct |
| 431 | * @buf: pointer to XDR buffer in which to encode data |
| 432 | * @p: current pointer inside XDR buffer |
| 433 | * |
| 434 | * Note: at the moment the RPC client only passes the length of our |
| 435 | * scratch buffer in the xdr_buf's header kvec. Previously this |
| 436 | * meant we needed to call xdr_adjust_iovec() after encoding the |
| 437 | * data. With the new scheme, the xdr_stream manages the details |
| 438 | * of the buffer length, and takes care of adjusting the kvec |
| 439 | * length for us. |
| 440 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 441 | void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 442 | { |
| 443 | struct kvec *iov = buf->head; |
Trond Myklebust | 334ccfd | 2005-06-22 17:16:19 +0000 | [diff] [blame] | 444 | int scratch_len = buf->buflen - buf->page_len - buf->tail[0].iov_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 445 | |
Trond Myklebust | 334ccfd | 2005-06-22 17:16:19 +0000 | [diff] [blame] | 446 | BUG_ON(scratch_len < 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | xdr->buf = buf; |
| 448 | xdr->iov = iov; |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 449 | xdr->p = (__be32 *)((char *)iov->iov_base + iov->iov_len); |
| 450 | xdr->end = (__be32 *)((char *)iov->iov_base + scratch_len); |
Trond Myklebust | 334ccfd | 2005-06-22 17:16:19 +0000 | [diff] [blame] | 451 | BUG_ON(iov->iov_len > scratch_len); |
| 452 | |
| 453 | if (p != xdr->p && p != NULL) { |
| 454 | size_t len; |
| 455 | |
| 456 | BUG_ON(p < xdr->p || p > xdr->end); |
| 457 | len = (char *)p - (char *)xdr->p; |
| 458 | xdr->p = p; |
| 459 | buf->len += len; |
| 460 | iov->iov_len += len; |
| 461 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | } |
| 463 | EXPORT_SYMBOL(xdr_init_encode); |
| 464 | |
| 465 | /** |
| 466 | * xdr_reserve_space - Reserve buffer space for sending |
| 467 | * @xdr: pointer to xdr_stream |
| 468 | * @nbytes: number of bytes to reserve |
| 469 | * |
| 470 | * Checks that we have enough buffer space to encode 'nbytes' more |
| 471 | * bytes of data. If so, update the total xdr_buf length, and |
| 472 | * adjust the length of the current kvec. |
| 473 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 474 | __be32 * xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 475 | { |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 476 | __be32 *p = xdr->p; |
| 477 | __be32 *q; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | |
| 479 | /* align nbytes on the next 32-bit boundary */ |
| 480 | nbytes += 3; |
| 481 | nbytes &= ~3; |
| 482 | q = p + (nbytes >> 2); |
| 483 | if (unlikely(q > xdr->end || q < p)) |
| 484 | return NULL; |
| 485 | xdr->p = q; |
| 486 | xdr->iov->iov_len += nbytes; |
| 487 | xdr->buf->len += nbytes; |
| 488 | return p; |
| 489 | } |
| 490 | EXPORT_SYMBOL(xdr_reserve_space); |
| 491 | |
| 492 | /** |
| 493 | * xdr_write_pages - Insert a list of pages into an XDR buffer for sending |
| 494 | * @xdr: pointer to xdr_stream |
| 495 | * @pages: list of pages |
| 496 | * @base: offset of first byte |
| 497 | * @len: length of data in bytes |
| 498 | * |
| 499 | */ |
| 500 | void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int base, |
| 501 | unsigned int len) |
| 502 | { |
| 503 | struct xdr_buf *buf = xdr->buf; |
| 504 | struct kvec *iov = buf->tail; |
| 505 | buf->pages = pages; |
| 506 | buf->page_base = base; |
| 507 | buf->page_len = len; |
| 508 | |
| 509 | iov->iov_base = (char *)xdr->p; |
| 510 | iov->iov_len = 0; |
| 511 | xdr->iov = iov; |
| 512 | |
| 513 | if (len & 3) { |
| 514 | unsigned int pad = 4 - (len & 3); |
| 515 | |
| 516 | BUG_ON(xdr->p >= xdr->end); |
| 517 | iov->iov_base = (char *)xdr->p + (len & 3); |
| 518 | iov->iov_len += pad; |
| 519 | len += pad; |
| 520 | *xdr->p++ = 0; |
| 521 | } |
| 522 | buf->buflen += len; |
| 523 | buf->len += len; |
| 524 | } |
| 525 | EXPORT_SYMBOL(xdr_write_pages); |
| 526 | |
| 527 | /** |
| 528 | * xdr_init_decode - Initialize an xdr_stream for decoding data. |
| 529 | * @xdr: pointer to xdr_stream struct |
| 530 | * @buf: pointer to XDR buffer from which to decode data |
| 531 | * @p: current pointer inside XDR buffer |
| 532 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 533 | void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 534 | { |
| 535 | struct kvec *iov = buf->head; |
| 536 | unsigned int len = iov->iov_len; |
| 537 | |
| 538 | if (len > buf->len) |
| 539 | len = buf->len; |
| 540 | xdr->buf = buf; |
| 541 | xdr->iov = iov; |
| 542 | xdr->p = p; |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 543 | xdr->end = (__be32 *)((char *)iov->iov_base + len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 544 | } |
| 545 | EXPORT_SYMBOL(xdr_init_decode); |
| 546 | |
| 547 | /** |
| 548 | * xdr_inline_decode - Retrieve non-page XDR data to decode |
| 549 | * @xdr: pointer to xdr_stream struct |
| 550 | * @nbytes: number of bytes of data to decode |
| 551 | * |
| 552 | * Check if the input buffer is long enough to enable us to decode |
| 553 | * 'nbytes' more bytes of data starting at the current position. |
| 554 | * If so return the current pointer, then update the current |
| 555 | * pointer position. |
| 556 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 557 | __be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 558 | { |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 559 | __be32 *p = xdr->p; |
| 560 | __be32 *q = p + XDR_QUADLEN(nbytes); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 561 | |
| 562 | if (unlikely(q > xdr->end || q < p)) |
| 563 | return NULL; |
| 564 | xdr->p = q; |
| 565 | return p; |
| 566 | } |
| 567 | EXPORT_SYMBOL(xdr_inline_decode); |
| 568 | |
| 569 | /** |
| 570 | * xdr_read_pages - Ensure page-based XDR data to decode is aligned at current pointer position |
| 571 | * @xdr: pointer to xdr_stream struct |
| 572 | * @len: number of bytes of page data |
| 573 | * |
| 574 | * Moves data beyond the current pointer position from the XDR head[] buffer |
| 575 | * into the page list. Any data that lies beyond current position + "len" |
Trond Myklebust | 8b23ea7 | 2006-06-09 09:34:21 -0400 | [diff] [blame] | 576 | * bytes is moved into the XDR tail[]. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 577 | */ |
| 578 | void xdr_read_pages(struct xdr_stream *xdr, unsigned int len) |
| 579 | { |
| 580 | struct xdr_buf *buf = xdr->buf; |
| 581 | struct kvec *iov; |
| 582 | ssize_t shift; |
| 583 | unsigned int end; |
| 584 | int padding; |
| 585 | |
| 586 | /* Realign pages to current pointer position */ |
| 587 | iov = buf->head; |
| 588 | shift = iov->iov_len + (char *)iov->iov_base - (char *)xdr->p; |
| 589 | if (shift > 0) |
| 590 | xdr_shrink_bufhead(buf, shift); |
| 591 | |
| 592 | /* Truncate page data and move it into the tail */ |
| 593 | if (buf->page_len > len) |
| 594 | xdr_shrink_pagelen(buf, buf->page_len - len); |
| 595 | padding = (XDR_QUADLEN(len) << 2) - len; |
| 596 | xdr->iov = iov = buf->tail; |
| 597 | /* Compute remaining message length. */ |
| 598 | end = iov->iov_len; |
| 599 | shift = buf->buflen - buf->len; |
| 600 | if (shift < end) |
| 601 | end -= shift; |
| 602 | else if (shift > 0) |
| 603 | end = 0; |
| 604 | /* |
| 605 | * Position current pointer at beginning of tail, and |
| 606 | * set remaining message length. |
| 607 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 608 | xdr->p = (__be32 *)((char *)iov->iov_base + padding); |
| 609 | xdr->end = (__be32 *)((char *)iov->iov_base + end); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 610 | } |
| 611 | EXPORT_SYMBOL(xdr_read_pages); |
| 612 | |
Trond Myklebust | 8b23ea7 | 2006-06-09 09:34:21 -0400 | [diff] [blame] | 613 | /** |
| 614 | * xdr_enter_page - decode data from the XDR page |
| 615 | * @xdr: pointer to xdr_stream struct |
| 616 | * @len: number of bytes of page data |
| 617 | * |
| 618 | * Moves data beyond the current pointer position from the XDR head[] buffer |
| 619 | * into the page list. Any data that lies beyond current position + "len" |
| 620 | * bytes is moved into the XDR tail[]. The current pointer is then |
| 621 | * repositioned at the beginning of the first XDR page. |
| 622 | */ |
| 623 | void xdr_enter_page(struct xdr_stream *xdr, unsigned int len) |
| 624 | { |
| 625 | char * kaddr = page_address(xdr->buf->pages[0]); |
| 626 | xdr_read_pages(xdr, len); |
| 627 | /* |
| 628 | * Position current pointer at beginning of tail, and |
| 629 | * set remaining message length. |
| 630 | */ |
| 631 | if (len > PAGE_CACHE_SIZE - xdr->buf->page_base) |
| 632 | len = PAGE_CACHE_SIZE - xdr->buf->page_base; |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 633 | xdr->p = (__be32 *)(kaddr + xdr->buf->page_base); |
| 634 | xdr->end = (__be32 *)((char *)xdr->p + len); |
Trond Myklebust | 8b23ea7 | 2006-06-09 09:34:21 -0400 | [diff] [blame] | 635 | } |
| 636 | EXPORT_SYMBOL(xdr_enter_page); |
| 637 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | static struct kvec empty_iov = {.iov_base = NULL, .iov_len = 0}; |
| 639 | |
| 640 | void |
| 641 | xdr_buf_from_iov(struct kvec *iov, struct xdr_buf *buf) |
| 642 | { |
| 643 | buf->head[0] = *iov; |
| 644 | buf->tail[0] = empty_iov; |
| 645 | buf->page_len = 0; |
| 646 | buf->buflen = buf->len = iov->iov_len; |
| 647 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 648 | EXPORT_SYMBOL(xdr_buf_from_iov); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 649 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 650 | /* Sets subbuf to the portion of buf of length len beginning base bytes |
| 651 | * from the start of buf. Returns -1 if base of length are out of bounds. */ |
| 652 | int |
| 653 | xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf, |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 654 | unsigned int base, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 656 | subbuf->buflen = subbuf->len = len; |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 657 | if (base < buf->head[0].iov_len) { |
| 658 | subbuf->head[0].iov_base = buf->head[0].iov_base + base; |
| 659 | subbuf->head[0].iov_len = min_t(unsigned int, len, |
| 660 | buf->head[0].iov_len - base); |
| 661 | len -= subbuf->head[0].iov_len; |
| 662 | base = 0; |
| 663 | } else { |
| 664 | subbuf->head[0].iov_base = NULL; |
| 665 | subbuf->head[0].iov_len = 0; |
| 666 | base -= buf->head[0].iov_len; |
| 667 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | |
| 669 | if (base < buf->page_len) { |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 670 | subbuf->page_len = min(buf->page_len - base, len); |
| 671 | base += buf->page_base; |
| 672 | subbuf->page_base = base & ~PAGE_CACHE_MASK; |
| 673 | subbuf->pages = &buf->pages[base >> PAGE_CACHE_SHIFT]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 674 | len -= subbuf->page_len; |
| 675 | base = 0; |
| 676 | } else { |
| 677 | base -= buf->page_len; |
| 678 | subbuf->page_len = 0; |
| 679 | } |
| 680 | |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 681 | if (base < buf->tail[0].iov_len) { |
| 682 | subbuf->tail[0].iov_base = buf->tail[0].iov_base + base; |
| 683 | subbuf->tail[0].iov_len = min_t(unsigned int, len, |
| 684 | buf->tail[0].iov_len - base); |
| 685 | len -= subbuf->tail[0].iov_len; |
| 686 | base = 0; |
| 687 | } else { |
| 688 | subbuf->tail[0].iov_base = NULL; |
| 689 | subbuf->tail[0].iov_len = 0; |
| 690 | base -= buf->tail[0].iov_len; |
| 691 | } |
| 692 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 693 | if (base || len) |
| 694 | return -1; |
| 695 | return 0; |
| 696 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 697 | EXPORT_SYMBOL(xdr_buf_subsegment); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 699 | static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | { |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 701 | unsigned int this_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 703 | this_len = min_t(unsigned int, len, subbuf->head[0].iov_len); |
| 704 | memcpy(obj, subbuf->head[0].iov_base, this_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | len -= this_len; |
| 706 | obj += this_len; |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 707 | this_len = min_t(unsigned int, len, subbuf->page_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | if (this_len) |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 709 | _copy_from_pages(obj, subbuf->pages, subbuf->page_base, this_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 710 | len -= this_len; |
| 711 | obj += this_len; |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 712 | this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len); |
| 713 | memcpy(obj, subbuf->tail[0].iov_base, this_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 714 | } |
| 715 | |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 716 | /* obj is assumed to point to allocated memory of size at least len: */ |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 717 | int read_bytes_from_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len) |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 718 | { |
| 719 | struct xdr_buf subbuf; |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 720 | int status; |
| 721 | |
| 722 | status = xdr_buf_subsegment(buf, &subbuf, base, len); |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 723 | if (status != 0) |
| 724 | return status; |
| 725 | __read_bytes_from_xdr_buf(&subbuf, obj, len); |
| 726 | return 0; |
| 727 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 728 | EXPORT_SYMBOL(read_bytes_from_xdr_buf); |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 729 | |
| 730 | static void __write_bytes_to_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len) |
| 731 | { |
| 732 | unsigned int this_len; |
| 733 | |
| 734 | this_len = min_t(unsigned int, len, subbuf->head[0].iov_len); |
| 735 | memcpy(subbuf->head[0].iov_base, obj, this_len); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 736 | len -= this_len; |
| 737 | obj += this_len; |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 738 | this_len = min_t(unsigned int, len, subbuf->page_len); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 739 | if (this_len) |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 740 | _copy_to_pages(subbuf->pages, subbuf->page_base, obj, this_len); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 741 | len -= this_len; |
| 742 | obj += this_len; |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 743 | this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len); |
| 744 | memcpy(subbuf->tail[0].iov_base, obj, this_len); |
| 745 | } |
| 746 | |
| 747 | /* obj is assumed to point to allocated memory of size at least len: */ |
| 748 | int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len) |
| 749 | { |
| 750 | struct xdr_buf subbuf; |
| 751 | int status; |
| 752 | |
| 753 | status = xdr_buf_subsegment(buf, &subbuf, base, len); |
| 754 | if (status != 0) |
| 755 | return status; |
| 756 | __write_bytes_to_xdr_buf(&subbuf, obj, len); |
| 757 | return 0; |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 758 | } |
| 759 | |
| 760 | int |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 761 | xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 762 | { |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 763 | __be32 raw; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 764 | int status; |
| 765 | |
| 766 | status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj)); |
| 767 | if (status) |
| 768 | return status; |
| 769 | *obj = ntohl(raw); |
| 770 | return 0; |
| 771 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 772 | EXPORT_SYMBOL(xdr_decode_word); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 773 | |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 774 | int |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 775 | xdr_encode_word(struct xdr_buf *buf, unsigned int base, u32 obj) |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 776 | { |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 777 | __be32 raw = htonl(obj); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 778 | |
| 779 | return write_bytes_to_xdr_buf(buf, base, &raw, sizeof(obj)); |
| 780 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 781 | EXPORT_SYMBOL(xdr_encode_word); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 782 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 783 | /* If the netobj starting offset bytes from the start of xdr_buf is contained |
| 784 | * entirely in the head or the tail, set object to point to it; otherwise |
| 785 | * try to find space for it at the end of the tail, copy it there, and |
| 786 | * set obj to point to it. */ |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 787 | int xdr_buf_read_netobj(struct xdr_buf *buf, struct xdr_netobj *obj, unsigned int offset) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 788 | { |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 789 | struct xdr_buf subbuf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 790 | |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 791 | if (xdr_decode_word(buf, offset, &obj->len)) |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 792 | return -EFAULT; |
| 793 | if (xdr_buf_subsegment(buf, &subbuf, offset + 4, obj->len)) |
| 794 | return -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 795 | |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 796 | /* Is the obj contained entirely in the head? */ |
| 797 | obj->data = subbuf.head[0].iov_base; |
| 798 | if (subbuf.head[0].iov_len == obj->len) |
| 799 | return 0; |
| 800 | /* ..or is the obj contained entirely in the tail? */ |
| 801 | obj->data = subbuf.tail[0].iov_base; |
| 802 | if (subbuf.tail[0].iov_len == obj->len) |
| 803 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 804 | |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 805 | /* use end of tail as storage for obj: |
| 806 | * (We don't copy to the beginning because then we'd have |
| 807 | * to worry about doing a potentially overlapping copy. |
| 808 | * This assumes the object is at most half the length of the |
| 809 | * tail.) */ |
| 810 | if (obj->len > buf->buflen - buf->len) |
| 811 | return -ENOMEM; |
| 812 | if (buf->tail[0].iov_len != 0) |
| 813 | obj->data = buf->tail[0].iov_base + buf->tail[0].iov_len; |
| 814 | else |
| 815 | obj->data = buf->head[0].iov_base + buf->head[0].iov_len; |
| 816 | __read_bytes_from_xdr_buf(&subbuf, obj->data, obj->len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 818 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 819 | EXPORT_SYMBOL(xdr_buf_read_netobj); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 820 | |
| 821 | /* Returns 0 on success, or else a negative error code. */ |
| 822 | static int |
| 823 | xdr_xcode_array2(struct xdr_buf *buf, unsigned int base, |
| 824 | struct xdr_array2_desc *desc, int encode) |
| 825 | { |
| 826 | char *elem = NULL, *c; |
| 827 | unsigned int copied = 0, todo, avail_here; |
| 828 | struct page **ppages = NULL; |
| 829 | int err; |
| 830 | |
| 831 | if (encode) { |
| 832 | if (xdr_encode_word(buf, base, desc->array_len) != 0) |
| 833 | return -EINVAL; |
| 834 | } else { |
| 835 | if (xdr_decode_word(buf, base, &desc->array_len) != 0 || |
Trond Myklebust | 58fcb8d | 2005-08-10 18:15:12 -0400 | [diff] [blame] | 836 | desc->array_len > desc->array_maxlen || |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 837 | (unsigned long) base + 4 + desc->array_len * |
| 838 | desc->elem_size > buf->len) |
| 839 | return -EINVAL; |
| 840 | } |
| 841 | base += 4; |
| 842 | |
| 843 | if (!desc->xcode) |
| 844 | return 0; |
| 845 | |
| 846 | todo = desc->array_len * desc->elem_size; |
| 847 | |
| 848 | /* process head */ |
| 849 | if (todo && base < buf->head->iov_len) { |
| 850 | c = buf->head->iov_base + base; |
| 851 | avail_here = min_t(unsigned int, todo, |
| 852 | buf->head->iov_len - base); |
| 853 | todo -= avail_here; |
| 854 | |
| 855 | while (avail_here >= desc->elem_size) { |
| 856 | err = desc->xcode(desc, c); |
| 857 | if (err) |
| 858 | goto out; |
| 859 | c += desc->elem_size; |
| 860 | avail_here -= desc->elem_size; |
| 861 | } |
| 862 | if (avail_here) { |
| 863 | if (!elem) { |
| 864 | elem = kmalloc(desc->elem_size, GFP_KERNEL); |
| 865 | err = -ENOMEM; |
| 866 | if (!elem) |
| 867 | goto out; |
| 868 | } |
| 869 | if (encode) { |
| 870 | err = desc->xcode(desc, elem); |
| 871 | if (err) |
| 872 | goto out; |
| 873 | memcpy(c, elem, avail_here); |
| 874 | } else |
| 875 | memcpy(elem, c, avail_here); |
| 876 | copied = avail_here; |
| 877 | } |
| 878 | base = buf->head->iov_len; /* align to start of pages */ |
| 879 | } |
| 880 | |
| 881 | /* process pages array */ |
| 882 | base -= buf->head->iov_len; |
| 883 | if (todo && base < buf->page_len) { |
| 884 | unsigned int avail_page; |
| 885 | |
| 886 | avail_here = min(todo, buf->page_len - base); |
| 887 | todo -= avail_here; |
| 888 | |
| 889 | base += buf->page_base; |
| 890 | ppages = buf->pages + (base >> PAGE_CACHE_SHIFT); |
| 891 | base &= ~PAGE_CACHE_MASK; |
| 892 | avail_page = min_t(unsigned int, PAGE_CACHE_SIZE - base, |
| 893 | avail_here); |
| 894 | c = kmap(*ppages) + base; |
| 895 | |
| 896 | while (avail_here) { |
| 897 | avail_here -= avail_page; |
| 898 | if (copied || avail_page < desc->elem_size) { |
| 899 | unsigned int l = min(avail_page, |
| 900 | desc->elem_size - copied); |
| 901 | if (!elem) { |
| 902 | elem = kmalloc(desc->elem_size, |
| 903 | GFP_KERNEL); |
| 904 | err = -ENOMEM; |
| 905 | if (!elem) |
| 906 | goto out; |
| 907 | } |
| 908 | if (encode) { |
| 909 | if (!copied) { |
| 910 | err = desc->xcode(desc, elem); |
| 911 | if (err) |
| 912 | goto out; |
| 913 | } |
| 914 | memcpy(c, elem + copied, l); |
| 915 | copied += l; |
| 916 | if (copied == desc->elem_size) |
| 917 | copied = 0; |
| 918 | } else { |
| 919 | memcpy(elem + copied, c, l); |
| 920 | copied += l; |
| 921 | if (copied == desc->elem_size) { |
| 922 | err = desc->xcode(desc, elem); |
| 923 | if (err) |
| 924 | goto out; |
| 925 | copied = 0; |
| 926 | } |
| 927 | } |
| 928 | avail_page -= l; |
| 929 | c += l; |
| 930 | } |
| 931 | while (avail_page >= desc->elem_size) { |
| 932 | err = desc->xcode(desc, c); |
| 933 | if (err) |
| 934 | goto out; |
| 935 | c += desc->elem_size; |
| 936 | avail_page -= desc->elem_size; |
| 937 | } |
| 938 | if (avail_page) { |
| 939 | unsigned int l = min(avail_page, |
| 940 | desc->elem_size - copied); |
| 941 | if (!elem) { |
| 942 | elem = kmalloc(desc->elem_size, |
| 943 | GFP_KERNEL); |
| 944 | err = -ENOMEM; |
| 945 | if (!elem) |
| 946 | goto out; |
| 947 | } |
| 948 | if (encode) { |
| 949 | if (!copied) { |
| 950 | err = desc->xcode(desc, elem); |
| 951 | if (err) |
| 952 | goto out; |
| 953 | } |
| 954 | memcpy(c, elem + copied, l); |
| 955 | copied += l; |
| 956 | if (copied == desc->elem_size) |
| 957 | copied = 0; |
| 958 | } else { |
| 959 | memcpy(elem + copied, c, l); |
| 960 | copied += l; |
| 961 | if (copied == desc->elem_size) { |
| 962 | err = desc->xcode(desc, elem); |
| 963 | if (err) |
| 964 | goto out; |
| 965 | copied = 0; |
| 966 | } |
| 967 | } |
| 968 | } |
| 969 | if (avail_here) { |
| 970 | kunmap(*ppages); |
| 971 | ppages++; |
| 972 | c = kmap(*ppages); |
| 973 | } |
| 974 | |
| 975 | avail_page = min(avail_here, |
| 976 | (unsigned int) PAGE_CACHE_SIZE); |
| 977 | } |
| 978 | base = buf->page_len; /* align to start of tail */ |
| 979 | } |
| 980 | |
| 981 | /* process tail */ |
| 982 | base -= buf->page_len; |
| 983 | if (todo) { |
| 984 | c = buf->tail->iov_base + base; |
| 985 | if (copied) { |
| 986 | unsigned int l = desc->elem_size - copied; |
| 987 | |
| 988 | if (encode) |
| 989 | memcpy(c, elem + copied, l); |
| 990 | else { |
| 991 | memcpy(elem + copied, c, l); |
| 992 | err = desc->xcode(desc, elem); |
| 993 | if (err) |
| 994 | goto out; |
| 995 | } |
| 996 | todo -= l; |
| 997 | c += l; |
| 998 | } |
| 999 | while (todo) { |
| 1000 | err = desc->xcode(desc, c); |
| 1001 | if (err) |
| 1002 | goto out; |
| 1003 | c += desc->elem_size; |
| 1004 | todo -= desc->elem_size; |
| 1005 | } |
| 1006 | } |
| 1007 | err = 0; |
| 1008 | |
| 1009 | out: |
Jesper Juhl | a51482b | 2005-11-08 09:41:34 -0800 | [diff] [blame] | 1010 | kfree(elem); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1011 | if (ppages) |
| 1012 | kunmap(*ppages); |
| 1013 | return err; |
| 1014 | } |
| 1015 | |
| 1016 | int |
| 1017 | xdr_decode_array2(struct xdr_buf *buf, unsigned int base, |
| 1018 | struct xdr_array2_desc *desc) |
| 1019 | { |
| 1020 | if (base >= buf->len) |
| 1021 | return -EINVAL; |
| 1022 | |
| 1023 | return xdr_xcode_array2(buf, base, desc, 0); |
| 1024 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 1025 | EXPORT_SYMBOL(xdr_decode_array2); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1026 | |
| 1027 | int |
| 1028 | xdr_encode_array2(struct xdr_buf *buf, unsigned int base, |
| 1029 | struct xdr_array2_desc *desc) |
| 1030 | { |
| 1031 | if ((unsigned long) base + 4 + desc->array_len * desc->elem_size > |
| 1032 | buf->head->iov_len + buf->page_len + buf->tail->iov_len) |
| 1033 | return -EINVAL; |
| 1034 | |
| 1035 | return xdr_xcode_array2(buf, base, desc, 1); |
| 1036 | } |
Trond Myklebust | a6eaf8b | 2007-07-14 15:39:58 -0400 | [diff] [blame] | 1037 | EXPORT_SYMBOL(xdr_encode_array2); |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1038 | |
| 1039 | int |
| 1040 | xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 1041 | int (*actor)(struct scatterlist *, void *), void *data) |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1042 | { |
| 1043 | int i, ret = 0; |
| 1044 | unsigned page_len, thislen, page_offset; |
| 1045 | struct scatterlist sg[1]; |
| 1046 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 1047 | sg_init_table(sg, 1); |
| 1048 | |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1049 | if (offset >= buf->head[0].iov_len) { |
| 1050 | offset -= buf->head[0].iov_len; |
| 1051 | } else { |
| 1052 | thislen = buf->head[0].iov_len - offset; |
| 1053 | if (thislen > len) |
| 1054 | thislen = len; |
| 1055 | sg_set_buf(sg, buf->head[0].iov_base + offset, thislen); |
| 1056 | ret = actor(sg, data); |
| 1057 | if (ret) |
| 1058 | goto out; |
| 1059 | offset = 0; |
| 1060 | len -= thislen; |
| 1061 | } |
| 1062 | if (len == 0) |
| 1063 | goto out; |
| 1064 | |
| 1065 | if (offset >= buf->page_len) { |
| 1066 | offset -= buf->page_len; |
| 1067 | } else { |
| 1068 | page_len = buf->page_len - offset; |
| 1069 | if (page_len > len) |
| 1070 | page_len = len; |
| 1071 | len -= page_len; |
| 1072 | page_offset = (offset + buf->page_base) & (PAGE_CACHE_SIZE - 1); |
| 1073 | i = (offset + buf->page_base) >> PAGE_CACHE_SHIFT; |
| 1074 | thislen = PAGE_CACHE_SIZE - page_offset; |
| 1075 | do { |
| 1076 | if (thislen > page_len) |
| 1077 | thislen = page_len; |
Jens Axboe | 642f149 | 2007-10-24 11:20:47 +0200 | [diff] [blame] | 1078 | sg_set_page(sg, buf->pages[i], thislen, page_offset); |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1079 | ret = actor(sg, data); |
| 1080 | if (ret) |
| 1081 | goto out; |
| 1082 | page_len -= thislen; |
| 1083 | i++; |
| 1084 | page_offset = 0; |
| 1085 | thislen = PAGE_CACHE_SIZE; |
| 1086 | } while (page_len != 0); |
| 1087 | offset = 0; |
| 1088 | } |
| 1089 | if (len == 0) |
| 1090 | goto out; |
| 1091 | if (offset < buf->tail[0].iov_len) { |
| 1092 | thislen = buf->tail[0].iov_len - offset; |
| 1093 | if (thislen > len) |
| 1094 | thislen = len; |
| 1095 | sg_set_buf(sg, buf->tail[0].iov_base + offset, thislen); |
| 1096 | ret = actor(sg, data); |
| 1097 | len -= thislen; |
| 1098 | } |
| 1099 | if (len != 0) |
| 1100 | ret = -EINVAL; |
| 1101 | out: |
| 1102 | return ret; |
| 1103 | } |
| 1104 | EXPORT_SYMBOL(xdr_process_buf); |
| 1105 | |