1 /* 2 * linux/fs/nfs/nfs2xdr.c 3 * 4 * XDR functions to encode/decode NFS RPC arguments and results. 5 * 6 * Copyright (C) 1992, 1993, 1994 Rick Sladkey 7 * Copyright (C) 1996 Olaf Kirch 8 * 04 Aug 1998 Ion Badulescu <ionut@cs.columbia.edu> 9 * FIFO's need special handling in NFSv2 10 */ 11 12 #include <linux/param.h> 13 #include <linux/time.h> 14 #include <linux/mm.h> 15 #include <linux/errno.h> 16 #include <linux/string.h> 17 #include <linux/in.h> 18 #include <linux/pagemap.h> 19 #include <linux/proc_fs.h> 20 #include <linux/sunrpc/clnt.h> 21 #include <linux/nfs.h> 22 #include <linux/nfs2.h> 23 #include <linux/nfs_fs.h> 24 #include "internal.h" 25 26 #define NFSDBG_FACILITY NFSDBG_XDR 27 28 /* Mapping from NFS error code to "errno" error code. */ 29 #define errno_NFSERR_IO EIO 30 31 /* 32 * Declare the space requirements for NFS arguments and replies as 33 * number of 32bit-words 34 */ 35 #define NFS_fhandle_sz (8) 36 #define NFS_sattr_sz (8) 37 #define NFS_filename_sz (1+(NFS2_MAXNAMLEN>>2)) 38 #define NFS_path_sz (1+(NFS2_MAXPATHLEN>>2)) 39 #define NFS_fattr_sz (17) 40 #define NFS_info_sz (5) 41 #define NFS_entry_sz (NFS_filename_sz+3) 42 43 #define NFS_diropargs_sz (NFS_fhandle_sz+NFS_filename_sz) 44 #define NFS_removeargs_sz (NFS_fhandle_sz+NFS_filename_sz) 45 #define NFS_sattrargs_sz (NFS_fhandle_sz+NFS_sattr_sz) 46 #define NFS_readlinkargs_sz (NFS_fhandle_sz) 47 #define NFS_readargs_sz (NFS_fhandle_sz+3) 48 #define NFS_writeargs_sz (NFS_fhandle_sz+4) 49 #define NFS_createargs_sz (NFS_diropargs_sz+NFS_sattr_sz) 50 #define NFS_renameargs_sz (NFS_diropargs_sz+NFS_diropargs_sz) 51 #define NFS_linkargs_sz (NFS_fhandle_sz+NFS_diropargs_sz) 52 #define NFS_symlinkargs_sz (NFS_diropargs_sz+1+NFS_sattr_sz) 53 #define NFS_readdirargs_sz (NFS_fhandle_sz+2) 54 55 #define NFS_attrstat_sz (1+NFS_fattr_sz) 56 #define NFS_diropres_sz (1+NFS_fhandle_sz+NFS_fattr_sz) 57 #define NFS_readlinkres_sz (2) 58 #define NFS_readres_sz (1+NFS_fattr_sz+1) 59 #define NFS_writeres_sz (NFS_attrstat_sz) 60 #define NFS_stat_sz (1) 61 #define NFS_readdirres_sz (1) 62 #define NFS_statfsres_sz (1+NFS_info_sz) 63 64 static int nfs_stat_to_errno(enum nfs_stat); 65 66 /* 67 * While encoding arguments, set up the reply buffer in advance to 68 * receive reply data directly into the page cache. 69 */ 70 static void prepare_reply_buffer(struct rpc_rqst *req, struct page **pages, 71 unsigned int base, unsigned int len, 72 unsigned int bufsize) 73 { 74 struct rpc_auth *auth = req->rq_cred->cr_auth; 75 unsigned int replen; 76 77 replen = RPC_REPHDRSIZE + auth->au_rslack + bufsize; 78 xdr_inline_pages(&req->rq_rcv_buf, replen << 2, pages, base, len); 79 } 80 81 /* 82 * Handle decode buffer overflows out-of-line. 83 */ 84 static void print_overflow_msg(const char *func, const struct xdr_stream *xdr) 85 { 86 dprintk("NFS: %s prematurely hit the end of our receive buffer. " 87 "Remaining buffer length is %tu words.\n", 88 func, xdr->end - xdr->p); 89 } 90 91 92 /* 93 * Encode/decode NFSv2 basic data types 94 * 95 * Basic NFSv2 data types are defined in section 2.3 of RFC 1094: 96 * "NFS: Network File System Protocol Specification". 97 * 98 * Not all basic data types have their own encoding and decoding 99 * functions. For run-time efficiency, some data types are encoded 100 * or decoded inline. 101 */ 102 103 /* 104 * typedef opaque nfsdata<>; 105 */ 106 static int decode_nfsdata(struct xdr_stream *xdr, struct nfs_pgio_res *result) 107 { 108 u32 recvd, count; 109 __be32 *p; 110 111 p = xdr_inline_decode(xdr, 4); 112 if (unlikely(p == NULL)) 113 goto out_overflow; 114 count = be32_to_cpup(p); 115 recvd = xdr_read_pages(xdr, count); 116 if (unlikely(count > recvd)) 117 goto out_cheating; 118 out: 119 result->eof = 0; /* NFSv2 does not pass EOF flag on the wire. */ 120 result->count = count; 121 return count; 122 out_cheating: 123 dprintk("NFS: server cheating in read result: " 124 "count %u > recvd %u\n", count, recvd); 125 count = recvd; 126 goto out; 127 out_overflow: 128 print_overflow_msg(__func__, xdr); 129 return -EIO; 130 } 131 132 /* 133 * enum stat { 134 * NFS_OK = 0, 135 * NFSERR_PERM = 1, 136 * NFSERR_NOENT = 2, 137 * NFSERR_IO = 5, 138 * NFSERR_NXIO = 6, 139 * NFSERR_ACCES = 13, 140 * NFSERR_EXIST = 17, 141 * NFSERR_NODEV = 19, 142 * NFSERR_NOTDIR = 20, 143 * NFSERR_ISDIR = 21, 144 * NFSERR_FBIG = 27, 145 * NFSERR_NOSPC = 28, 146 * NFSERR_ROFS = 30, 147 * NFSERR_NAMETOOLONG = 63, 148 * NFSERR_NOTEMPTY = 66, 149 * NFSERR_DQUOT = 69, 150 * NFSERR_STALE = 70, 151 * NFSERR_WFLUSH = 99 152 * }; 153 */ 154 static int decode_stat(struct xdr_stream *xdr, enum nfs_stat *status) 155 { 156 __be32 *p; 157 158 p = xdr_inline_decode(xdr, 4); 159 if (unlikely(p == NULL)) 160 goto out_overflow; 161 *status = be32_to_cpup(p); 162 return 0; 163 out_overflow: 164 print_overflow_msg(__func__, xdr); 165 return -EIO; 166 } 167 168 /* 169 * 2.3.2. ftype 170 * 171 * enum ftype { 172 * NFNON = 0, 173 * NFREG = 1, 174 * NFDIR = 2, 175 * NFBLK = 3, 176 * NFCHR = 4, 177 * NFLNK = 5 178 * }; 179 * 180 */ 181 static __be32 *xdr_decode_ftype(__be32 *p, u32 *type) 182 { 183 *type = be32_to_cpup(p++); 184 if (unlikely(*type > NF2FIFO)) 185 *type = NFBAD; 186 return p; 187 } 188 189 /* 190 * 2.3.3. fhandle 191 * 192 * typedef opaque fhandle[FHSIZE]; 193 */ 194 static void encode_fhandle(struct xdr_stream *xdr, const struct nfs_fh *fh) 195 { 196 __be32 *p; 197 198 p = xdr_reserve_space(xdr, NFS2_FHSIZE); 199 memcpy(p, fh->data, NFS2_FHSIZE); 200 } 201 202 static int decode_fhandle(struct xdr_stream *xdr, struct nfs_fh *fh) 203 { 204 __be32 *p; 205 206 p = xdr_inline_decode(xdr, NFS2_FHSIZE); 207 if (unlikely(p == NULL)) 208 goto out_overflow; 209 fh->size = NFS2_FHSIZE; 210 memcpy(fh->data, p, NFS2_FHSIZE); 211 return 0; 212 out_overflow: 213 print_overflow_msg(__func__, xdr); 214 return -EIO; 215 } 216 217 /* 218 * 2.3.4. timeval 219 * 220 * struct timeval { 221 * unsigned int seconds; 222 * unsigned int useconds; 223 * }; 224 */ 225 static __be32 *xdr_encode_time(__be32 *p, const struct timespec *timep) 226 { 227 *p++ = cpu_to_be32(timep->tv_sec); 228 if (timep->tv_nsec != 0) 229 *p++ = cpu_to_be32(timep->tv_nsec / NSEC_PER_USEC); 230 else 231 *p++ = cpu_to_be32(0); 232 return p; 233 } 234 235 /* 236 * Passing the invalid value useconds=1000000 is a Sun convention for 237 * "set to current server time". It's needed to make permissions checks 238 * for the "touch" program across v2 mounts to Solaris and Irix servers 239 * work correctly. See description of sattr in section 6.1 of "NFS 240 * Illustrated" by Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5. 241 */ 242 static __be32 *xdr_encode_current_server_time(__be32 *p, 243 const struct timespec *timep) 244 { 245 *p++ = cpu_to_be32(timep->tv_sec); 246 *p++ = cpu_to_be32(1000000); 247 return p; 248 } 249 250 static __be32 *xdr_decode_time(__be32 *p, struct timespec *timep) 251 { 252 timep->tv_sec = be32_to_cpup(p++); 253 timep->tv_nsec = be32_to_cpup(p++) * NSEC_PER_USEC; 254 return p; 255 } 256 257 /* 258 * 2.3.5. fattr 259 * 260 * struct fattr { 261 * ftype type; 262 * unsigned int mode; 263 * unsigned int nlink; 264 * unsigned int uid; 265 * unsigned int gid; 266 * unsigned int size; 267 * unsigned int blocksize; 268 * unsigned int rdev; 269 * unsigned int blocks; 270 * unsigned int fsid; 271 * unsigned int fileid; 272 * timeval atime; 273 * timeval mtime; 274 * timeval ctime; 275 * }; 276 * 277 */ 278 static int decode_fattr(struct xdr_stream *xdr, struct nfs_fattr *fattr) 279 { 280 u32 rdev, type; 281 __be32 *p; 282 283 p = xdr_inline_decode(xdr, NFS_fattr_sz << 2); 284 if (unlikely(p == NULL)) 285 goto out_overflow; 286 287 fattr->valid |= NFS_ATTR_FATTR_V2; 288 289 p = xdr_decode_ftype(p, &type); 290 291 fattr->mode = be32_to_cpup(p++); 292 fattr->nlink = be32_to_cpup(p++); 293 fattr->uid = make_kuid(&init_user_ns, be32_to_cpup(p++)); 294 if (!uid_valid(fattr->uid)) 295 goto out_uid; 296 fattr->gid = make_kgid(&init_user_ns, be32_to_cpup(p++)); 297 if (!gid_valid(fattr->gid)) 298 goto out_gid; 299 300 fattr->size = be32_to_cpup(p++); 301 fattr->du.nfs2.blocksize = be32_to_cpup(p++); 302 303 rdev = be32_to_cpup(p++); 304 fattr->rdev = new_decode_dev(rdev); 305 if (type == (u32)NFCHR && rdev == (u32)NFS2_FIFO_DEV) { 306 fattr->mode = (fattr->mode & ~S_IFMT) | S_IFIFO; 307 fattr->rdev = 0; 308 } 309 310 fattr->du.nfs2.blocks = be32_to_cpup(p++); 311 fattr->fsid.major = be32_to_cpup(p++); 312 fattr->fsid.minor = 0; 313 fattr->fileid = be32_to_cpup(p++); 314 315 p = xdr_decode_time(p, &fattr->atime); 316 p = xdr_decode_time(p, &fattr->mtime); 317 xdr_decode_time(p, &fattr->ctime); 318 fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime); 319 320 return 0; 321 out_uid: 322 dprintk("NFS: returned invalid uid\n"); 323 return -EINVAL; 324 out_gid: 325 dprintk("NFS: returned invalid gid\n"); 326 return -EINVAL; 327 out_overflow: 328 print_overflow_msg(__func__, xdr); 329 return -EIO; 330 } 331 332 /* 333 * 2.3.6. sattr 334 * 335 * struct sattr { 336 * unsigned int mode; 337 * unsigned int uid; 338 * unsigned int gid; 339 * unsigned int size; 340 * timeval atime; 341 * timeval mtime; 342 * }; 343 */ 344 345 #define NFS2_SATTR_NOT_SET (0xffffffff) 346 347 static __be32 *xdr_time_not_set(__be32 *p) 348 { 349 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 350 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 351 return p; 352 } 353 354 static void encode_sattr(struct xdr_stream *xdr, const struct iattr *attr) 355 { 356 __be32 *p; 357 358 p = xdr_reserve_space(xdr, NFS_sattr_sz << 2); 359 360 if (attr->ia_valid & ATTR_MODE) 361 *p++ = cpu_to_be32(attr->ia_mode); 362 else 363 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 364 if (attr->ia_valid & ATTR_UID) 365 *p++ = cpu_to_be32(from_kuid(&init_user_ns, attr->ia_uid)); 366 else 367 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 368 if (attr->ia_valid & ATTR_GID) 369 *p++ = cpu_to_be32(from_kgid(&init_user_ns, attr->ia_gid)); 370 else 371 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 372 if (attr->ia_valid & ATTR_SIZE) 373 *p++ = cpu_to_be32((u32)attr->ia_size); 374 else 375 *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET); 376 377 if (attr->ia_valid & ATTR_ATIME_SET) 378 p = xdr_encode_time(p, &attr->ia_atime); 379 else if (attr->ia_valid & ATTR_ATIME) 380 p = xdr_encode_current_server_time(p, &attr->ia_atime); 381 else 382 p = xdr_time_not_set(p); 383 if (attr->ia_valid & ATTR_MTIME_SET) 384 xdr_encode_time(p, &attr->ia_mtime); 385 else if (attr->ia_valid & ATTR_MTIME) 386 xdr_encode_current_server_time(p, &attr->ia_mtime); 387 else 388 xdr_time_not_set(p); 389 } 390 391 /* 392 * 2.3.7. filename 393 * 394 * typedef string filename<MAXNAMLEN>; 395 */ 396 static void encode_filename(struct xdr_stream *xdr, 397 const char *name, u32 length) 398 { 399 __be32 *p; 400 401 WARN_ON_ONCE(length > NFS2_MAXNAMLEN); 402 p = xdr_reserve_space(xdr, 4 + length); 403 xdr_encode_opaque(p, name, length); 404 } 405 406 static int decode_filename_inline(struct xdr_stream *xdr, 407 const char **name, u32 *length) 408 { 409 __be32 *p; 410 u32 count; 411 412 p = xdr_inline_decode(xdr, 4); 413 if (unlikely(p == NULL)) 414 goto out_overflow; 415 count = be32_to_cpup(p); 416 if (count > NFS3_MAXNAMLEN) 417 goto out_nametoolong; 418 p = xdr_inline_decode(xdr, count); 419 if (unlikely(p == NULL)) 420 goto out_overflow; 421 *name = (const char *)p; 422 *length = count; 423 return 0; 424 out_nametoolong: 425 dprintk("NFS: returned filename too long: %u\n", count); 426 return -ENAMETOOLONG; 427 out_overflow: 428 print_overflow_msg(__func__, xdr); 429 return -EIO; 430 } 431 432 /* 433 * 2.3.8. path 434 * 435 * typedef string path<MAXPATHLEN>; 436 */ 437 static void encode_path(struct xdr_stream *xdr, struct page **pages, u32 length) 438 { 439 __be32 *p; 440 441 p = xdr_reserve_space(xdr, 4); 442 *p = cpu_to_be32(length); 443 xdr_write_pages(xdr, pages, 0, length); 444 } 445 446 static int decode_path(struct xdr_stream *xdr) 447 { 448 u32 length, recvd; 449 __be32 *p; 450 451 p = xdr_inline_decode(xdr, 4); 452 if (unlikely(p == NULL)) 453 goto out_overflow; 454 length = be32_to_cpup(p); 455 if (unlikely(length >= xdr->buf->page_len || length > NFS_MAXPATHLEN)) 456 goto out_size; 457 recvd = xdr_read_pages(xdr, length); 458 if (unlikely(length > recvd)) 459 goto out_cheating; 460 xdr_terminate_string(xdr->buf, length); 461 return 0; 462 out_size: 463 dprintk("NFS: returned pathname too long: %u\n", length); 464 return -ENAMETOOLONG; 465 out_cheating: 466 dprintk("NFS: server cheating in pathname result: " 467 "length %u > received %u\n", length, recvd); 468 return -EIO; 469 out_overflow: 470 print_overflow_msg(__func__, xdr); 471 return -EIO; 472 } 473 474 /* 475 * 2.3.9. attrstat 476 * 477 * union attrstat switch (stat status) { 478 * case NFS_OK: 479 * fattr attributes; 480 * default: 481 * void; 482 * }; 483 */ 484 static int decode_attrstat(struct xdr_stream *xdr, struct nfs_fattr *result) 485 { 486 enum nfs_stat status; 487 int error; 488 489 error = decode_stat(xdr, &status); 490 if (unlikely(error)) 491 goto out; 492 if (status != NFS_OK) 493 goto out_default; 494 error = decode_fattr(xdr, result); 495 out: 496 return error; 497 out_default: 498 return nfs_stat_to_errno(status); 499 } 500 501 /* 502 * 2.3.10. diropargs 503 * 504 * struct diropargs { 505 * fhandle dir; 506 * filename name; 507 * }; 508 */ 509 static void encode_diropargs(struct xdr_stream *xdr, const struct nfs_fh *fh, 510 const char *name, u32 length) 511 { 512 encode_fhandle(xdr, fh); 513 encode_filename(xdr, name, length); 514 } 515 516 /* 517 * 2.3.11. diropres 518 * 519 * union diropres switch (stat status) { 520 * case NFS_OK: 521 * struct { 522 * fhandle file; 523 * fattr attributes; 524 * } diropok; 525 * default: 526 * void; 527 * }; 528 */ 529 static int decode_diropok(struct xdr_stream *xdr, struct nfs_diropok *result) 530 { 531 int error; 532 533 error = decode_fhandle(xdr, result->fh); 534 if (unlikely(error)) 535 goto out; 536 error = decode_fattr(xdr, result->fattr); 537 out: 538 return error; 539 } 540 541 static int decode_diropres(struct xdr_stream *xdr, struct nfs_diropok *result) 542 { 543 enum nfs_stat status; 544 int error; 545 546 error = decode_stat(xdr, &status); 547 if (unlikely(error)) 548 goto out; 549 if (status != NFS_OK) 550 goto out_default; 551 error = decode_diropok(xdr, result); 552 out: 553 return error; 554 out_default: 555 return nfs_stat_to_errno(status); 556 } 557 558 559 /* 560 * NFSv2 XDR encode functions 561 * 562 * NFSv2 argument types are defined in section 2.2 of RFC 1094: 563 * "NFS: Network File System Protocol Specification". 564 */ 565 566 static void nfs2_xdr_enc_fhandle(struct rpc_rqst *req, 567 struct xdr_stream *xdr, 568 const struct nfs_fh *fh) 569 { 570 encode_fhandle(xdr, fh); 571 } 572 573 /* 574 * 2.2.3. sattrargs 575 * 576 * struct sattrargs { 577 * fhandle file; 578 * sattr attributes; 579 * }; 580 */ 581 static void nfs2_xdr_enc_sattrargs(struct rpc_rqst *req, 582 struct xdr_stream *xdr, 583 const struct nfs_sattrargs *args) 584 { 585 encode_fhandle(xdr, args->fh); 586 encode_sattr(xdr, args->sattr); 587 } 588 589 static void nfs2_xdr_enc_diropargs(struct rpc_rqst *req, 590 struct xdr_stream *xdr, 591 const struct nfs_diropargs *args) 592 { 593 encode_diropargs(xdr, args->fh, args->name, args->len); 594 } 595 596 static void nfs2_xdr_enc_readlinkargs(struct rpc_rqst *req, 597 struct xdr_stream *xdr, 598 const struct nfs_readlinkargs *args) 599 { 600 encode_fhandle(xdr, args->fh); 601 prepare_reply_buffer(req, args->pages, args->pgbase, 602 args->pglen, NFS_readlinkres_sz); 603 } 604 605 /* 606 * 2.2.7. readargs 607 * 608 * struct readargs { 609 * fhandle file; 610 * unsigned offset; 611 * unsigned count; 612 * unsigned totalcount; 613 * }; 614 */ 615 static void encode_readargs(struct xdr_stream *xdr, 616 const struct nfs_pgio_args *args) 617 { 618 u32 offset = args->offset; 619 u32 count = args->count; 620 __be32 *p; 621 622 encode_fhandle(xdr, args->fh); 623 624 p = xdr_reserve_space(xdr, 4 + 4 + 4); 625 *p++ = cpu_to_be32(offset); 626 *p++ = cpu_to_be32(count); 627 *p = cpu_to_be32(count); 628 } 629 630 static void nfs2_xdr_enc_readargs(struct rpc_rqst *req, 631 struct xdr_stream *xdr, 632 const struct nfs_pgio_args *args) 633 { 634 encode_readargs(xdr, args); 635 prepare_reply_buffer(req, args->pages, args->pgbase, 636 args->count, NFS_readres_sz); 637 req->rq_rcv_buf.flags |= XDRBUF_READ; 638 } 639 640 /* 641 * 2.2.9. writeargs 642 * 643 * struct writeargs { 644 * fhandle file; 645 * unsigned beginoffset; 646 * unsigned offset; 647 * unsigned totalcount; 648 * nfsdata data; 649 * }; 650 */ 651 static void encode_writeargs(struct xdr_stream *xdr, 652 const struct nfs_pgio_args *args) 653 { 654 u32 offset = args->offset; 655 u32 count = args->count; 656 __be32 *p; 657 658 encode_fhandle(xdr, args->fh); 659 660 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4); 661 *p++ = cpu_to_be32(offset); 662 *p++ = cpu_to_be32(offset); 663 *p++ = cpu_to_be32(count); 664 665 /* nfsdata */ 666 *p = cpu_to_be32(count); 667 xdr_write_pages(xdr, args->pages, args->pgbase, count); 668 } 669 670 static void nfs2_xdr_enc_writeargs(struct rpc_rqst *req, 671 struct xdr_stream *xdr, 672 const struct nfs_pgio_args *args) 673 { 674 encode_writeargs(xdr, args); 675 xdr->buf->flags |= XDRBUF_WRITE; 676 } 677 678 /* 679 * 2.2.10. createargs 680 * 681 * struct createargs { 682 * diropargs where; 683 * sattr attributes; 684 * }; 685 */ 686 static void nfs2_xdr_enc_createargs(struct rpc_rqst *req, 687 struct xdr_stream *xdr, 688 const struct nfs_createargs *args) 689 { 690 encode_diropargs(xdr, args->fh, args->name, args->len); 691 encode_sattr(xdr, args->sattr); 692 } 693 694 static void nfs2_xdr_enc_removeargs(struct rpc_rqst *req, 695 struct xdr_stream *xdr, 696 const struct nfs_removeargs *args) 697 { 698 encode_diropargs(xdr, args->fh, args->name.name, args->name.len); 699 } 700 701 /* 702 * 2.2.12. renameargs 703 * 704 * struct renameargs { 705 * diropargs from; 706 * diropargs to; 707 * }; 708 */ 709 static void nfs2_xdr_enc_renameargs(struct rpc_rqst *req, 710 struct xdr_stream *xdr, 711 const struct nfs_renameargs *args) 712 { 713 const struct qstr *old = args->old_name; 714 const struct qstr *new = args->new_name; 715 716 encode_diropargs(xdr, args->old_dir, old->name, old->len); 717 encode_diropargs(xdr, args->new_dir, new->name, new->len); 718 } 719 720 /* 721 * 2.2.13. linkargs 722 * 723 * struct linkargs { 724 * fhandle from; 725 * diropargs to; 726 * }; 727 */ 728 static void nfs2_xdr_enc_linkargs(struct rpc_rqst *req, 729 struct xdr_stream *xdr, 730 const struct nfs_linkargs *args) 731 { 732 encode_fhandle(xdr, args->fromfh); 733 encode_diropargs(xdr, args->tofh, args->toname, args->tolen); 734 } 735 736 /* 737 * 2.2.14. symlinkargs 738 * 739 * struct symlinkargs { 740 * diropargs from; 741 * path to; 742 * sattr attributes; 743 * }; 744 */ 745 static void nfs2_xdr_enc_symlinkargs(struct rpc_rqst *req, 746 struct xdr_stream *xdr, 747 const struct nfs_symlinkargs *args) 748 { 749 encode_diropargs(xdr, args->fromfh, args->fromname, args->fromlen); 750 encode_path(xdr, args->pages, args->pathlen); 751 encode_sattr(xdr, args->sattr); 752 } 753 754 /* 755 * 2.2.17. readdirargs 756 * 757 * struct readdirargs { 758 * fhandle dir; 759 * nfscookie cookie; 760 * unsigned count; 761 * }; 762 */ 763 static void encode_readdirargs(struct xdr_stream *xdr, 764 const struct nfs_readdirargs *args) 765 { 766 __be32 *p; 767 768 encode_fhandle(xdr, args->fh); 769 770 p = xdr_reserve_space(xdr, 4 + 4); 771 *p++ = cpu_to_be32(args->cookie); 772 *p = cpu_to_be32(args->count); 773 } 774 775 static void nfs2_xdr_enc_readdirargs(struct rpc_rqst *req, 776 struct xdr_stream *xdr, 777 const struct nfs_readdirargs *args) 778 { 779 encode_readdirargs(xdr, args); 780 prepare_reply_buffer(req, args->pages, 0, 781 args->count, NFS_readdirres_sz); 782 } 783 784 /* 785 * NFSv2 XDR decode functions 786 * 787 * NFSv2 result types are defined in section 2.2 of RFC 1094: 788 * "NFS: Network File System Protocol Specification". 789 */ 790 791 static int nfs2_xdr_dec_stat(struct rpc_rqst *req, struct xdr_stream *xdr, 792 void *__unused) 793 { 794 enum nfs_stat status; 795 int error; 796 797 error = decode_stat(xdr, &status); 798 if (unlikely(error)) 799 goto out; 800 if (status != NFS_OK) 801 goto out_default; 802 out: 803 return error; 804 out_default: 805 return nfs_stat_to_errno(status); 806 } 807 808 static int nfs2_xdr_dec_attrstat(struct rpc_rqst *req, struct xdr_stream *xdr, 809 struct nfs_fattr *result) 810 { 811 return decode_attrstat(xdr, result); 812 } 813 814 static int nfs2_xdr_dec_diropres(struct rpc_rqst *req, struct xdr_stream *xdr, 815 struct nfs_diropok *result) 816 { 817 return decode_diropres(xdr, result); 818 } 819 820 /* 821 * 2.2.6. readlinkres 822 * 823 * union readlinkres switch (stat status) { 824 * case NFS_OK: 825 * path data; 826 * default: 827 * void; 828 * }; 829 */ 830 static int nfs2_xdr_dec_readlinkres(struct rpc_rqst *req, 831 struct xdr_stream *xdr, void *__unused) 832 { 833 enum nfs_stat status; 834 int error; 835 836 error = decode_stat(xdr, &status); 837 if (unlikely(error)) 838 goto out; 839 if (status != NFS_OK) 840 goto out_default; 841 error = decode_path(xdr); 842 out: 843 return error; 844 out_default: 845 return nfs_stat_to_errno(status); 846 } 847 848 /* 849 * 2.2.7. readres 850 * 851 * union readres switch (stat status) { 852 * case NFS_OK: 853 * fattr attributes; 854 * nfsdata data; 855 * default: 856 * void; 857 * }; 858 */ 859 static int nfs2_xdr_dec_readres(struct rpc_rqst *req, struct xdr_stream *xdr, 860 struct nfs_pgio_res *result) 861 { 862 enum nfs_stat status; 863 int error; 864 865 error = decode_stat(xdr, &status); 866 if (unlikely(error)) 867 goto out; 868 if (status != NFS_OK) 869 goto out_default; 870 error = decode_fattr(xdr, result->fattr); 871 if (unlikely(error)) 872 goto out; 873 error = decode_nfsdata(xdr, result); 874 out: 875 return error; 876 out_default: 877 return nfs_stat_to_errno(status); 878 } 879 880 static int nfs2_xdr_dec_writeres(struct rpc_rqst *req, struct xdr_stream *xdr, 881 struct nfs_pgio_res *result) 882 { 883 /* All NFSv2 writes are "file sync" writes */ 884 result->verf->committed = NFS_FILE_SYNC; 885 return decode_attrstat(xdr, result->fattr); 886 } 887 888 /** 889 * nfs2_decode_dirent - Decode a single NFSv2 directory entry stored in 890 * the local page cache. 891 * @xdr: XDR stream where entry resides 892 * @entry: buffer to fill in with entry data 893 * @plus: boolean indicating whether this should be a readdirplus entry 894 * 895 * Returns zero if successful, otherwise a negative errno value is 896 * returned. 897 * 898 * This function is not invoked during READDIR reply decoding, but 899 * rather whenever an application invokes the getdents(2) system call 900 * on a directory already in our cache. 901 * 902 * 2.2.17. entry 903 * 904 * struct entry { 905 * unsigned fileid; 906 * filename name; 907 * nfscookie cookie; 908 * entry *nextentry; 909 * }; 910 */ 911 int nfs2_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, 912 int plus) 913 { 914 __be32 *p; 915 int error; 916 917 p = xdr_inline_decode(xdr, 4); 918 if (unlikely(p == NULL)) 919 goto out_overflow; 920 if (*p++ == xdr_zero) { 921 p = xdr_inline_decode(xdr, 4); 922 if (unlikely(p == NULL)) 923 goto out_overflow; 924 if (*p++ == xdr_zero) 925 return -EAGAIN; 926 entry->eof = 1; 927 return -EBADCOOKIE; 928 } 929 930 p = xdr_inline_decode(xdr, 4); 931 if (unlikely(p == NULL)) 932 goto out_overflow; 933 entry->ino = be32_to_cpup(p); 934 935 error = decode_filename_inline(xdr, &entry->name, &entry->len); 936 if (unlikely(error)) 937 return error; 938 939 /* 940 * The type (size and byte order) of nfscookie isn't defined in 941 * RFC 1094. This implementation assumes that it's an XDR uint32. 942 */ 943 entry->prev_cookie = entry->cookie; 944 p = xdr_inline_decode(xdr, 4); 945 if (unlikely(p == NULL)) 946 goto out_overflow; 947 entry->cookie = be32_to_cpup(p); 948 949 entry->d_type = DT_UNKNOWN; 950 951 return 0; 952 953 out_overflow: 954 print_overflow_msg(__func__, xdr); 955 return -EAGAIN; 956 } 957 958 /* 959 * 2.2.17. readdirres 960 * 961 * union readdirres switch (stat status) { 962 * case NFS_OK: 963 * struct { 964 * entry *entries; 965 * bool eof; 966 * } readdirok; 967 * default: 968 * void; 969 * }; 970 * 971 * Read the directory contents into the page cache, but don't 972 * touch them. The actual decoding is done by nfs2_decode_dirent() 973 * during subsequent nfs_readdir() calls. 974 */ 975 static int decode_readdirok(struct xdr_stream *xdr) 976 { 977 return xdr_read_pages(xdr, xdr->buf->page_len); 978 } 979 980 static int nfs2_xdr_dec_readdirres(struct rpc_rqst *req, 981 struct xdr_stream *xdr, void *__unused) 982 { 983 enum nfs_stat status; 984 int error; 985 986 error = decode_stat(xdr, &status); 987 if (unlikely(error)) 988 goto out; 989 if (status != NFS_OK) 990 goto out_default; 991 error = decode_readdirok(xdr); 992 out: 993 return error; 994 out_default: 995 return nfs_stat_to_errno(status); 996 } 997 998 /* 999 * 2.2.18. statfsres 1000 * 1001 * union statfsres (stat status) { 1002 * case NFS_OK: 1003 * struct { 1004 * unsigned tsize; 1005 * unsigned bsize; 1006 * unsigned blocks; 1007 * unsigned bfree; 1008 * unsigned bavail; 1009 * } info; 1010 * default: 1011 * void; 1012 * }; 1013 */ 1014 static int decode_info(struct xdr_stream *xdr, struct nfs2_fsstat *result) 1015 { 1016 __be32 *p; 1017 1018 p = xdr_inline_decode(xdr, NFS_info_sz << 2); 1019 if (unlikely(p == NULL)) 1020 goto out_overflow; 1021 result->tsize = be32_to_cpup(p++); 1022 result->bsize = be32_to_cpup(p++); 1023 result->blocks = be32_to_cpup(p++); 1024 result->bfree = be32_to_cpup(p++); 1025 result->bavail = be32_to_cpup(p); 1026 return 0; 1027 out_overflow: 1028 print_overflow_msg(__func__, xdr); 1029 return -EIO; 1030 } 1031 1032 static int nfs2_xdr_dec_statfsres(struct rpc_rqst *req, struct xdr_stream *xdr, 1033 struct nfs2_fsstat *result) 1034 { 1035 enum nfs_stat status; 1036 int error; 1037 1038 error = decode_stat(xdr, &status); 1039 if (unlikely(error)) 1040 goto out; 1041 if (status != NFS_OK) 1042 goto out_default; 1043 error = decode_info(xdr, result); 1044 out: 1045 return error; 1046 out_default: 1047 return nfs_stat_to_errno(status); 1048 } 1049 1050 1051 /* 1052 * We need to translate between nfs status return values and 1053 * the local errno values which may not be the same. 1054 */ 1055 static const struct { 1056 int stat; 1057 int errno; 1058 } nfs_errtbl[] = { 1059 { NFS_OK, 0 }, 1060 { NFSERR_PERM, -EPERM }, 1061 { NFSERR_NOENT, -ENOENT }, 1062 { NFSERR_IO, -errno_NFSERR_IO}, 1063 { NFSERR_NXIO, -ENXIO }, 1064 /* { NFSERR_EAGAIN, -EAGAIN }, */ 1065 { NFSERR_ACCES, -EACCES }, 1066 { NFSERR_EXIST, -EEXIST }, 1067 { NFSERR_XDEV, -EXDEV }, 1068 { NFSERR_NODEV, -ENODEV }, 1069 { NFSERR_NOTDIR, -ENOTDIR }, 1070 { NFSERR_ISDIR, -EISDIR }, 1071 { NFSERR_INVAL, -EINVAL }, 1072 { NFSERR_FBIG, -EFBIG }, 1073 { NFSERR_NOSPC, -ENOSPC }, 1074 { NFSERR_ROFS, -EROFS }, 1075 { NFSERR_MLINK, -EMLINK }, 1076 { NFSERR_NAMETOOLONG, -ENAMETOOLONG }, 1077 { NFSERR_NOTEMPTY, -ENOTEMPTY }, 1078 { NFSERR_DQUOT, -EDQUOT }, 1079 { NFSERR_STALE, -ESTALE }, 1080 { NFSERR_REMOTE, -EREMOTE }, 1081 #ifdef EWFLUSH 1082 { NFSERR_WFLUSH, -EWFLUSH }, 1083 #endif 1084 { NFSERR_BADHANDLE, -EBADHANDLE }, 1085 { NFSERR_NOT_SYNC, -ENOTSYNC }, 1086 { NFSERR_BAD_COOKIE, -EBADCOOKIE }, 1087 { NFSERR_NOTSUPP, -ENOTSUPP }, 1088 { NFSERR_TOOSMALL, -ETOOSMALL }, 1089 { NFSERR_SERVERFAULT, -EREMOTEIO }, 1090 { NFSERR_BADTYPE, -EBADTYPE }, 1091 { NFSERR_JUKEBOX, -EJUKEBOX }, 1092 { -1, -EIO } 1093 }; 1094 1095 /** 1096 * nfs_stat_to_errno - convert an NFS status code to a local errno 1097 * @status: NFS status code to convert 1098 * 1099 * Returns a local errno value, or -EIO if the NFS status code is 1100 * not recognized. This function is used jointly by NFSv2 and NFSv3. 1101 */ 1102 static int nfs_stat_to_errno(enum nfs_stat status) 1103 { 1104 int i; 1105 1106 for (i = 0; nfs_errtbl[i].stat != -1; i++) { 1107 if (nfs_errtbl[i].stat == (int)status) 1108 return nfs_errtbl[i].errno; 1109 } 1110 dprintk("NFS: Unrecognized nfs status value: %u\n", status); 1111 return nfs_errtbl[i].errno; 1112 } 1113 1114 #define PROC(proc, argtype, restype, timer) \ 1115 [NFSPROC_##proc] = { \ 1116 .p_proc = NFSPROC_##proc, \ 1117 .p_encode = (kxdreproc_t)nfs2_xdr_enc_##argtype, \ 1118 .p_decode = (kxdrdproc_t)nfs2_xdr_dec_##restype, \ 1119 .p_arglen = NFS_##argtype##_sz, \ 1120 .p_replen = NFS_##restype##_sz, \ 1121 .p_timer = timer, \ 1122 .p_statidx = NFSPROC_##proc, \ 1123 .p_name = #proc, \ 1124 } 1125 struct rpc_procinfo nfs_procedures[] = { 1126 PROC(GETATTR, fhandle, attrstat, 1), 1127 PROC(SETATTR, sattrargs, attrstat, 0), 1128 PROC(LOOKUP, diropargs, diropres, 2), 1129 PROC(READLINK, readlinkargs, readlinkres, 3), 1130 PROC(READ, readargs, readres, 3), 1131 PROC(WRITE, writeargs, writeres, 4), 1132 PROC(CREATE, createargs, diropres, 0), 1133 PROC(REMOVE, removeargs, stat, 0), 1134 PROC(RENAME, renameargs, stat, 0), 1135 PROC(LINK, linkargs, stat, 0), 1136 PROC(SYMLINK, symlinkargs, stat, 0), 1137 PROC(MKDIR, createargs, diropres, 0), 1138 PROC(RMDIR, diropargs, stat, 0), 1139 PROC(READDIR, readdirargs, readdirres, 3), 1140 PROC(STATFS, fhandle, statfsres, 0), 1141 }; 1142 1143 const struct rpc_version nfs_version2 = { 1144 .number = 2, 1145 .nrprocs = ARRAY_SIZE(nfs_procedures), 1146 .procs = nfs_procedures 1147 }; 1148