fs/nfs/callback_xdr.c

   1 /*
   2  * linux/fs/nfs/callback_xdr.c
   3  *
   4  * Copyright (C) 2004 Trond Myklebust
   5  *
   6  * NFSv4 callback encode/decode procedures
   7  */
   8 #include <linux/kernel.h>
   9 #include <linux/sunrpc/svc.h>
  10 #include <linux/nfs4.h>
  11 #include <linux/nfs_fs.h>
  12 #include "nfs4_fs.h"
  13 #include "callback.h"
  14
  15 #define CB_OP_TAGLEN_MAXSZ      (512)
  16 #define CB_OP_HDR_RES_MAXSZ     (2 + CB_OP_TAGLEN_MAXSZ)
  17 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4)
  18 #define CB_OP_GETATTR_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ + \
  19                                 CB_OP_GETATTR_BITMAP_MAXSZ + \
  20                                 2 + 2 + 3 + 3)
  21 #define CB_OP_RECALL_RES_MAXSZ  (CB_OP_HDR_RES_MAXSZ)
  22
  23 #if defined(CONFIG_NFS_V4_1)
  24 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  25                                         4 + 1 + 3)
  26 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  27 #endif /* CONFIG_NFS_V4_1 */
  28
  29 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  30
  31 typedef __be32 (*callback_process_op_t)(void *, void *);
  32 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  33 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  34
  35
  36 struct callback_op {
  37         callback_process_op_t process_op;
  38         callback_decode_arg_t decode_args;
  39         callback_encode_res_t encode_res;
  40         long res_maxsize;
  41 };
  42
  43 static struct callback_op callback_ops[];
  44
  45 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  46 {
  47         return htonl(NFS4_OK);
  48 }
  49
  50 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  51 {
  52         return xdr_argsize_check(rqstp, p);
  53 }
  54
  55 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  56 {
  57         return xdr_ressize_check(rqstp, p);
  58 }
  59
  60 static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
  61 {
  62         __be32 *p;
  63
  64         p = xdr_inline_decode(xdr, nbytes);
  65         if (unlikely(p == NULL))
  66                 printk(KERN_WARNING "NFSv4 callback reply buffer overflowed!\n");
  67         return p;
  68 }
  69
  70 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
  71 {
  72         __be32 *p;
  73
  74         p = read_buf(xdr, 4);
  75         if (unlikely(p == NULL))
  76                 return htonl(NFS4ERR_RESOURCE);
  77         *len = ntohl(*p);
  78
  79         if (*len != 0) {
  80                 p = read_buf(xdr, *len);
  81                 if (unlikely(p == NULL))
  82                         return htonl(NFS4ERR_RESOURCE);
  83                 *str = (const char *)p;
  84         } else
  85                 *str = NULL;
  86
  87         return 0;
  88 }
  89
  90 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  91 {
  92         __be32 *p;
  93
  94         p = read_buf(xdr, 4);
  95         if (unlikely(p == NULL))
  96                 return htonl(NFS4ERR_RESOURCE);
  97         fh->size = ntohl(*p);
  98         if (fh->size > NFS4_FHSIZE)
  99                 return htonl(NFS4ERR_BADHANDLE);
 100         p = read_buf(xdr, fh->size);
 101         if (unlikely(p == NULL))
 102                 return htonl(NFS4ERR_RESOURCE);
 103         memcpy(&fh->data[0], p, fh->size);
 104         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 105         return 0;
 106 }
 107
 108 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 109 {
 110         __be32 *p;
 111         unsigned int attrlen;
 112
 113         p = read_buf(xdr, 4);
 114         if (unlikely(p == NULL))
 115                 return htonl(NFS4ERR_RESOURCE);
 116         attrlen = ntohl(*p);
 117         p = read_buf(xdr, attrlen << 2);
 118         if (unlikely(p == NULL))
 119                 return htonl(NFS4ERR_RESOURCE);
 120         if (likely(attrlen > 0))
 121                 bitmap[0] = ntohl(*p++);
 122         if (attrlen > 1)
 123                 bitmap[1] = ntohl(*p);
 124         return 0;
 125 }
 126
 127 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 128 {
 129         __be32 *p;
 130
 131         p = read_buf(xdr, 16);
 132         if (unlikely(p == NULL))
 133                 return htonl(NFS4ERR_RESOURCE);
 134         memcpy(stateid->data, p, 16);
 135         return 0;
 136 }
 137
 138 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 139 {
 140         __be32 *p;
 141         __be32 status;
 142
 143         status = decode_string(xdr, &hdr->taglen, &hdr->tag);
 144         if (unlikely(status != 0))
 145                 return status;
 146         /* We do not like overly long tags! */
 147         if (hdr->taglen > CB_OP_TAGLEN_MAXSZ - 12) {
 148                 printk("NFSv4 CALLBACK %s: client sent tag of length %u\n",
 149                                 __func__, hdr->taglen);
 150                 return htonl(NFS4ERR_RESOURCE);
 151         }
 152         p = read_buf(xdr, 12);
 153         if (unlikely(p == NULL))
 154                 return htonl(NFS4ERR_RESOURCE);
 155         hdr->minorversion = ntohl(*p++);
 156         /* Check minor version is zero or one. */
 157         if (hdr->minorversion <= 1) {
 158                 p++;    /* skip callback_ident */
 159         } else {
 160                 printk(KERN_WARNING "%s: NFSv4 server callback with "
 161                         "illegal minor version %u!\n",
 162                         __func__, hdr->minorversion);
 163                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 164         }
 165         hdr->nops = ntohl(*p);
 166         dprintk("%s: minorversion %d nops %d\n", __func__,
 167                 hdr->minorversion, hdr->nops);
 168         return 0;
 169 }
 170
 171 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 172 {
 173         __be32 *p;
 174         p = read_buf(xdr, 4);
 175         if (unlikely(p == NULL))
 176                 return htonl(NFS4ERR_RESOURCE);
 177         *op = ntohl(*p);
 178         return 0;
 179 }
 180
 181 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 182 {
 183         __be32 status;
 184
 185         status = decode_fh(xdr, &args->fh);
 186         if (unlikely(status != 0))
 187                 goto out;
 188         args->addr = svc_addr(rqstp);
 189         status = decode_bitmap(xdr, args->bitmap);
 190 out:
 191         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 192         return status;
 193 }
 194
 195 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 196 {
 197         __be32 *p;
 198         __be32 status;
 199
 200         args->addr = svc_addr(rqstp);
 201         status = decode_stateid(xdr, &args->stateid);
 202         if (unlikely(status != 0))
 203                 goto out;
 204         p = read_buf(xdr, 4);
 205         if (unlikely(p == NULL)) {
 206                 status = htonl(NFS4ERR_RESOURCE);
 207                 goto out;
 208         }
 209         args->truncate = ntohl(*p);
 210         status = decode_fh(xdr, &args->fh);
 211 out:
 212         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 213         return status;
 214 }
 215
 216 #if defined(CONFIG_NFS_V4_1)
 217
 218 static unsigned decode_sessionid(struct xdr_stream *xdr,
 219                                  struct nfs4_sessionid *sid)
 220 {
 221         uint32_t *p;
 222         int len = NFS4_MAX_SESSIONID_LEN;
 223
 224         p = read_buf(xdr, len);
 225         if (unlikely(p == NULL))
 226                 return htonl(NFS4ERR_RESOURCE);
 227
 228         memcpy(sid->data, p, len);
 229         return 0;
 230 }
 231
 232 static unsigned decode_rc_list(struct xdr_stream *xdr,
 233                                struct referring_call_list *rc_list)
 234 {
 235         uint32_t *p;
 236         int i;
 237         unsigned status;
 238
 239         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 240         if (status)
 241                 goto out;
 242
 243         status = htonl(NFS4ERR_RESOURCE);
 244         p = read_buf(xdr, sizeof(uint32_t));
 245         if (unlikely(p == NULL))
 246                 goto out;
 247
 248         rc_list->rcl_nrefcalls = ntohl(*p++);
 249         if (rc_list->rcl_nrefcalls) {
 250                 p = read_buf(xdr,
 251                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 252                 if (unlikely(p == NULL))
 253                         goto out;
 254                 rc_list->rcl_refcalls = kmalloc(rc_list->rcl_nrefcalls *
 255                                                 sizeof(*rc_list->rcl_refcalls),
 256                                                 GFP_KERNEL);
 257                 if (unlikely(rc_list->rcl_refcalls == NULL))
 258                         goto out;
 259                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 260                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 261                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 262                 }
 263         }
 264         status = 0;
 265
 266 out:
 267         return status;
 268 }
 269
 270 static unsigned decode_cb_sequence_args(struct svc_rqst *rqstp,
 271                                         struct xdr_stream *xdr,
 272                                         struct cb_sequenceargs *args)
 273 {
 274         uint32_t *p;
 275         int i;
 276         unsigned status;
 277
 278         status = decode_sessionid(xdr, &args->csa_sessionid);
 279         if (status)
 280                 goto out;
 281
 282         status = htonl(NFS4ERR_RESOURCE);
 283         p = read_buf(xdr, 5 * sizeof(uint32_t));
 284         if (unlikely(p == NULL))
 285                 goto out;
 286
 287         args->csa_addr = svc_addr(rqstp);
 288         args->csa_sequenceid = ntohl(*p++);
 289         args->csa_slotid = ntohl(*p++);
 290         args->csa_highestslotid = ntohl(*p++);
 291         args->csa_cachethis = ntohl(*p++);
 292         args->csa_nrclists = ntohl(*p++);
 293         args->csa_rclists = NULL;
 294         if (args->csa_nrclists) {
 295                 args->csa_rclists = kmalloc(args->csa_nrclists *
 296                                             sizeof(*args->csa_rclists),
 297                                             GFP_KERNEL);
 298                 if (unlikely(args->csa_rclists == NULL))
 299                         goto out;
 300
 301                 for (i = 0; i < args->csa_nrclists; i++) {
 302                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 303                         if (status)
 304                                 goto out_free;
 305                 }
 306         }
 307         status = 0;
 308
 309         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
 310                 "highestslotid %u cachethis %d nrclists %u\n",
 311                 __func__,
 312                 ((u32 *)&args->csa_sessionid)[0],
 313                 ((u32 *)&args->csa_sessionid)[1],
 314                 ((u32 *)&args->csa_sessionid)[2],
 315                 ((u32 *)&args->csa_sessionid)[3],
 316                 args->csa_sequenceid, args->csa_slotid,
 317                 args->csa_highestslotid, args->csa_cachethis,
 318                 args->csa_nrclists);
 319 out:
 320         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 321         return status;
 322
 323 out_free:
 324         for (i = 0; i < args->csa_nrclists; i++)
 325                 kfree(args->csa_rclists[i].rcl_refcalls);
 326         kfree(args->csa_rclists);
 327         goto out;
 328 }
 329
 330 static unsigned decode_recallany_args(struct svc_rqst *rqstp,
 331                                       struct xdr_stream *xdr,
 332                                       struct cb_recallanyargs *args)
 333 {
 334         uint32_t *p;
 335
 336         args->craa_addr = svc_addr(rqstp);
 337         p = read_buf(xdr, 4);
 338         if (unlikely(p == NULL))
 339                 return htonl(NFS4ERR_BADXDR);
 340         args->craa_objs_to_keep = ntohl(*p++);
 341         p = read_buf(xdr, 4);
 342         if (unlikely(p == NULL))
 343                 return htonl(NFS4ERR_BADXDR);
 344         args->craa_type_mask = ntohl(*p);
 345
 346         return 0;
 347 }
 348
 349 #endif /* CONFIG_NFS_V4_1 */
 350
 351 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 352 {
 353         __be32 *p;
 354
 355         p = xdr_reserve_space(xdr, 4 + len);
 356         if (unlikely(p == NULL))
 357                 return htonl(NFS4ERR_RESOURCE);
 358         xdr_encode_opaque(p, str, len);
 359         return 0;
 360 }
 361
 362 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
 363 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
 364 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
 365 {
 366         __be32 bm[2];
 367         __be32 *p;
 368
 369         bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
 370         bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
 371         if (bm[1] != 0) {
 372                 p = xdr_reserve_space(xdr, 16);
 373                 if (unlikely(p == NULL))
 374                         return htonl(NFS4ERR_RESOURCE);
 375                 *p++ = htonl(2);
 376                 *p++ = bm[0];
 377                 *p++ = bm[1];
 378         } else if (bm[0] != 0) {
 379                 p = xdr_reserve_space(xdr, 12);
 380                 if (unlikely(p == NULL))
 381                         return htonl(NFS4ERR_RESOURCE);
 382                 *p++ = htonl(1);
 383                 *p++ = bm[0];
 384         } else {
 385                 p = xdr_reserve_space(xdr, 8);
 386                 if (unlikely(p == NULL))
 387                         return htonl(NFS4ERR_RESOURCE);
 388                 *p++ = htonl(0);
 389         }
 390         *savep = p;
 391         return 0;
 392 }
 393
 394 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 395 {
 396         __be32 *p;
 397
 398         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 399                 return 0;
 400         p = xdr_reserve_space(xdr, 8);
 401         if (unlikely(!p))
 402                 return htonl(NFS4ERR_RESOURCE);
 403         p = xdr_encode_hyper(p, change);
 404         return 0;
 405 }
 406
 407 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 408 {
 409         __be32 *p;
 410
 411         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 412                 return 0;
 413         p = xdr_reserve_space(xdr, 8);
 414         if (unlikely(!p))
 415                 return htonl(NFS4ERR_RESOURCE);
 416         p = xdr_encode_hyper(p, size);
 417         return 0;
 418 }
 419
 420 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 421 {
 422         __be32 *p;
 423
 424         p = xdr_reserve_space(xdr, 12);
 425         if (unlikely(!p))
 426                 return htonl(NFS4ERR_RESOURCE);
 427         p = xdr_encode_hyper(p, time->tv_sec);
 428         *p = htonl(time->tv_nsec);
 429         return 0;
 430 }
 431
 432 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 433 {
 434         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 435                 return 0;
 436         return encode_attr_time(xdr,time);
 437 }
 438
 439 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 440 {
 441         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 442                 return 0;
 443         return encode_attr_time(xdr,time);
 444 }
 445
 446 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 447 {
 448         __be32 status;
 449
 450         hdr->status = xdr_reserve_space(xdr, 4);
 451         if (unlikely(hdr->status == NULL))
 452                 return htonl(NFS4ERR_RESOURCE);
 453         status = encode_string(xdr, hdr->taglen, hdr->tag);
 454         if (unlikely(status != 0))
 455                 return status;
 456         hdr->nops = xdr_reserve_space(xdr, 4);
 457         if (unlikely(hdr->nops == NULL))
 458                 return htonl(NFS4ERR_RESOURCE);
 459         return 0;
 460 }
 461
 462 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 463 {
 464         __be32 *p;
 465
 466         p = xdr_reserve_space(xdr, 8);
 467         if (unlikely(p == NULL))
 468                 return htonl(NFS4ERR_RESOURCE);
 469         *p++ = htonl(op);
 470         *p = res;
 471         return 0;
 472 }
 473
 474 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 475 {
 476         __be32 *savep = NULL;
 477         __be32 status = res->status;
 478
 479         if (unlikely(status != 0))
 480                 goto out;
 481         status = encode_attr_bitmap(xdr, res->bitmap, &savep);
 482         if (unlikely(status != 0))
 483                 goto out;
 484         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 485         if (unlikely(status != 0))
 486                 goto out;
 487         status = encode_attr_size(xdr, res->bitmap, res->size);
 488         if (unlikely(status != 0))
 489                 goto out;
 490         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 491         if (unlikely(status != 0))
 492                 goto out;
 493         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 494         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 495 out:
 496         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 497         return status;
 498 }
 499
 500 #if defined(CONFIG_NFS_V4_1)
 501
 502 static unsigned encode_sessionid(struct xdr_stream *xdr,
 503                                  const struct nfs4_sessionid *sid)
 504 {
 505         uint32_t *p;
 506         int len = NFS4_MAX_SESSIONID_LEN;
 507
 508         p = xdr_reserve_space(xdr, len);
 509         if (unlikely(p == NULL))
 510                 return htonl(NFS4ERR_RESOURCE);
 511
 512         memcpy(p, sid, len);
 513         return 0;
 514 }
 515
 516 static unsigned encode_cb_sequence_res(struct svc_rqst *rqstp,
 517                                        struct xdr_stream *xdr,
 518                                        const struct cb_sequenceres *res)
 519 {
 520         uint32_t *p;
 521         unsigned status = res->csr_status;
 522
 523         if (unlikely(status != 0))
 524                 goto out;
 525
 526         encode_sessionid(xdr, &res->csr_sessionid);
 527
 528         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 529         if (unlikely(p == NULL))
 530                 return htonl(NFS4ERR_RESOURCE);
 531
 532         *p++ = htonl(res->csr_sequenceid);
 533         *p++ = htonl(res->csr_slotid);
 534         *p++ = htonl(res->csr_highestslotid);
 535         *p++ = htonl(res->csr_target_highestslotid);
 536 out:
 537         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 538         return status;
 539 }
 540
 541 static __be32
 542 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 543 {
 544         if (op_nr == OP_CB_SEQUENCE) {
 545                 if (nop != 0)
 546                         return htonl(NFS4ERR_SEQUENCE_POS);
 547         } else {
 548                 if (nop == 0)
 549                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 550         }
 551
 552         switch (op_nr) {
 553         case OP_CB_GETATTR:
 554         case OP_CB_RECALL:
 555         case OP_CB_SEQUENCE:
 556         case OP_CB_RECALL_ANY:
 557                 *op = &callback_ops[op_nr];
 558                 break;
 559
 560         case OP_CB_LAYOUTRECALL:
 561         case OP_CB_NOTIFY_DEVICEID:
 562         case OP_CB_NOTIFY:
 563         case OP_CB_PUSH_DELEG:
 564         case OP_CB_RECALLABLE_OBJ_AVAIL:
 565         case OP_CB_RECALL_SLOT:
 566         case OP_CB_WANTS_CANCELLED:
 567         case OP_CB_NOTIFY_LOCK:
 568                 return htonl(NFS4ERR_NOTSUPP);
 569
 570         default:
 571                 return htonl(NFS4ERR_OP_ILLEGAL);
 572         }
 573
 574         return htonl(NFS_OK);
 575 }
 576
 577 #else /* CONFIG_NFS_V4_1 */
 578
 579 static __be32
 580 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 581 {
 582         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 583 }
 584
 585 #endif /* CONFIG_NFS_V4_1 */
 586
 587 static __be32
 588 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 589 {
 590         switch (op_nr) {
 591         case OP_CB_GETATTR:
 592         case OP_CB_RECALL:
 593                 *op = &callback_ops[op_nr];
 594                 break;
 595         default:
 596                 return htonl(NFS4ERR_OP_ILLEGAL);
 597         }
 598
 599         return htonl(NFS_OK);
 600 }
 601
 602 static __be32 process_op(uint32_t minorversion, int nop,
 603                 struct svc_rqst *rqstp,
 604                 struct xdr_stream *xdr_in, void *argp,
 605                 struct xdr_stream *xdr_out, void *resp)
 606 {
 607         struct callback_op *op = &callback_ops[0];
 608         unsigned int op_nr = OP_CB_ILLEGAL;
 609         __be32 status;
 610         long maxlen;
 611         __be32 res;
 612
 613         dprintk("%s: start\n", __func__);
 614         status = decode_op_hdr(xdr_in, &op_nr);
 615         if (unlikely(status)) {
 616                 status = htonl(NFS4ERR_OP_ILLEGAL);
 617                 goto out;
 618         }
 619
 620         dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
 621                 __func__, minorversion, nop, op_nr);
 622
 623         status = minorversion ? preprocess_nfs41_op(nop, op_nr, &op) :
 624                                 preprocess_nfs4_op(op_nr, &op);
 625         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 626                 op_nr = OP_CB_ILLEGAL;
 627 out:
 628         maxlen = xdr_out->end - xdr_out->p;
 629         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 630                 if (likely(status == 0 && op->decode_args != NULL))
 631                         status = op->decode_args(rqstp, xdr_in, argp);
 632                 if (likely(status == 0 && op->process_op != NULL))
 633                         status = op->process_op(argp, resp);
 634         } else
 635                 status = htonl(NFS4ERR_RESOURCE);
 636
 637         res = encode_op_hdr(xdr_out, op_nr, status);
 638         if (status == 0)
 639                 status = res;
 640         if (op->encode_res != NULL && status == 0)
 641                 status = op->encode_res(rqstp, xdr_out, resp);
 642         dprintk("%s: done, status = %d\n", __func__, ntohl(status));
 643         return status;
 644 }
 645
 646 /*
 647  * Decode, process and encode a COMPOUND
 648  */
 649 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 650 {
 651         struct cb_compound_hdr_arg hdr_arg = { 0 };
 652         struct cb_compound_hdr_res hdr_res = { NULL };
 653         struct xdr_stream xdr_in, xdr_out;
 654         __be32 *p;
 655         __be32 status;
 656         unsigned int nops = 0;
 657
 658         dprintk("%s: start\n", __func__);
 659
 660         xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
 661
 662         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 663         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 664
 665         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 666         if (status == __constant_htonl(NFS4ERR_RESOURCE))
 667                 return rpc_garbage_args;
 668
 669         hdr_res.taglen = hdr_arg.taglen;
 670         hdr_res.tag = hdr_arg.tag;
 671         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
 672                 return rpc_system_err;
 673
 674         while (status == 0 && nops != hdr_arg.nops) {
 675                 status = process_op(hdr_arg.minorversion, nops,
 676                                     rqstp, &xdr_in, argp, &xdr_out, resp);
 677                 nops++;
 678         }
 679
 680         *hdr_res.status = status;
 681         *hdr_res.nops = htonl(nops);
 682         dprintk("%s: done, status = %u\n", __func__, ntohl(status));
 683         return rpc_success;
 684 }
 685
 686 /*
 687  * Define NFS4 callback COMPOUND ops.
 688  */
 689 static struct callback_op callback_ops[] = {
 690         [0] = {
 691                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 692         },
 693         [OP_CB_GETATTR] = {
 694                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
 695                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
 696                 .encode_res = (callback_encode_res_t)encode_getattr_res,
 697                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
 698         },
 699         [OP_CB_RECALL] = {
 700                 .process_op = (callback_process_op_t)nfs4_callback_recall,
 701                 .decode_args = (callback_decode_arg_t)decode_recall_args,
 702                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
 703         },
 704 #if defined(CONFIG_NFS_V4_1)
 705         [OP_CB_SEQUENCE] = {
 706                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
 707                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
 708                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
 709                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
 710         },
 711         [OP_CB_RECALL_ANY] = {
 712                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
 713                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
 714                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
 715         },
 716 #endif /* CONFIG_NFS_V4_1 */
 717 };
 718
 719 /*
 720  * Define NFS4 callback procedures
 721  */
 722 static struct svc_procedure nfs4_callback_procedures1[] = {
 723         [CB_NULL] = {
 724                 .pc_func = nfs4_callback_null,
 725                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
 726                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 727                 .pc_xdrressize = 1,
 728         },
 729         [CB_COMPOUND] = {
 730                 .pc_func = nfs4_callback_compound,
 731                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 732                 .pc_argsize = 256,
 733                 .pc_ressize = 256,
 734                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
 735         }
 736 };
 737
 738 struct svc_version nfs4_callback_version1 = {
 739         .vs_vers = 1,
 740         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 741         .vs_proc = nfs4_callback_procedures1,
 742         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 743         .vs_dispatch = NULL,
 744 };
 745
 746 struct svc_version nfs4_callback_version4 = {
 747         .vs_vers = 4,
 748         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 749         .vs_proc = nfs4_callback_procedures1,
 750         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 751         .vs_dispatch = NULL,
 752 };