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 <linux/ratelimit.h>
  13 #include <linux/printk.h>
  14 #include <linux/slab.h>
  15 #include <linux/sunrpc/bc_xprt.h>
  16 #include "nfs4_fs.h"
  17 #include "callback.h"
  18 #include "internal.h"
  19 #include "nfs4session.h"
  20
  21 #define CB_OP_TAGLEN_MAXSZ      (512)
  22 #define CB_OP_HDR_RES_MAXSZ     (2 + CB_OP_TAGLEN_MAXSZ)
  23 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4)
  24 #define CB_OP_GETATTR_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ + \
  25                                 CB_OP_GETATTR_BITMAP_MAXSZ + \
  26                                 2 + 2 + 3 + 3)
  27 #define CB_OP_RECALL_RES_MAXSZ  (CB_OP_HDR_RES_MAXSZ)
  28
  29 #if defined(CONFIG_NFS_V4_1)
  30 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  31 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  32 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  33                                         4 + 1 + 3)
  34 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  35 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  36 #endif /* CONFIG_NFS_V4_1 */
  37
  38 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  39
  40 /* Internal error code */
  41 #define NFS4ERR_RESOURCE_HDR    11050
  42
  43 typedef __be32 (*callback_process_op_t)(void *, void *,
  44                                         struct cb_process_state *);
  45 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  46 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  47
  48
  49 struct callback_op {
  50         callback_process_op_t process_op;
  51         callback_decode_arg_t decode_args;
  52         callback_encode_res_t encode_res;
  53         long res_maxsize;
  54 };
  55
  56 static struct callback_op callback_ops[];
  57
  58 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  59 {
  60         return htonl(NFS4_OK);
  61 }
  62
  63 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  64 {
  65         return xdr_argsize_check(rqstp, p);
  66 }
  67
  68 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  69 {
  70         return xdr_ressize_check(rqstp, p);
  71 }
  72
  73 static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
  74 {
  75         __be32 *p;
  76
  77         p = xdr_inline_decode(xdr, nbytes);
  78         if (unlikely(p == NULL))
  79                 printk(KERN_WARNING "NFS: NFSv4 callback reply buffer overflowed!\n");
  80         return p;
  81 }
  82
  83 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
  84 {
  85         __be32 *p;
  86
  87         p = read_buf(xdr, 4);
  88         if (unlikely(p == NULL))
  89                 return htonl(NFS4ERR_RESOURCE);
  90         *len = ntohl(*p);
  91
  92         if (*len != 0) {
  93                 p = read_buf(xdr, *len);
  94                 if (unlikely(p == NULL))
  95                         return htonl(NFS4ERR_RESOURCE);
  96                 *str = (const char *)p;
  97         } else
  98                 *str = NULL;
  99
 100         return 0;
 101 }
 102
 103 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
 104 {
 105         __be32 *p;
 106
 107         p = read_buf(xdr, 4);
 108         if (unlikely(p == NULL))
 109                 return htonl(NFS4ERR_RESOURCE);
 110         fh->size = ntohl(*p);
 111         if (fh->size > NFS4_FHSIZE)
 112                 return htonl(NFS4ERR_BADHANDLE);
 113         p = read_buf(xdr, fh->size);
 114         if (unlikely(p == NULL))
 115                 return htonl(NFS4ERR_RESOURCE);
 116         memcpy(&fh->data[0], p, fh->size);
 117         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 118         return 0;
 119 }
 120
 121 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 122 {
 123         __be32 *p;
 124         unsigned int attrlen;
 125
 126         p = read_buf(xdr, 4);
 127         if (unlikely(p == NULL))
 128                 return htonl(NFS4ERR_RESOURCE);
 129         attrlen = ntohl(*p);
 130         p = read_buf(xdr, attrlen << 2);
 131         if (unlikely(p == NULL))
 132                 return htonl(NFS4ERR_RESOURCE);
 133         if (likely(attrlen > 0))
 134                 bitmap[0] = ntohl(*p++);
 135         if (attrlen > 1)
 136                 bitmap[1] = ntohl(*p);
 137         return 0;
 138 }
 139
 140 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 141 {
 142         __be32 *p;
 143
 144         p = read_buf(xdr, NFS4_STATEID_SIZE);
 145         if (unlikely(p == NULL))
 146                 return htonl(NFS4ERR_RESOURCE);
 147         memcpy(stateid, p, NFS4_STATEID_SIZE);
 148         return 0;
 149 }
 150
 151 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 152 {
 153         __be32 *p;
 154         __be32 status;
 155
 156         status = decode_string(xdr, &hdr->taglen, &hdr->tag);
 157         if (unlikely(status != 0))
 158                 return status;
 159         /* We do not like overly long tags! */
 160         if (hdr->taglen > CB_OP_TAGLEN_MAXSZ - 12) {
 161                 printk("NFS: NFSv4 CALLBACK %s: client sent tag of length %u\n",
 162                                 __func__, hdr->taglen);
 163                 return htonl(NFS4ERR_RESOURCE);
 164         }
 165         p = read_buf(xdr, 12);
 166         if (unlikely(p == NULL))
 167                 return htonl(NFS4ERR_RESOURCE);
 168         hdr->minorversion = ntohl(*p++);
 169         /* Check minor version is zero or one. */
 170         if (hdr->minorversion <= 1) {
 171                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 */
 172         } else {
 173                 pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
 174                         "illegal minor version %u!\n",
 175                         __func__, hdr->minorversion);
 176                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 177         }
 178         hdr->nops = ntohl(*p);
 179         dprintk("%s: minorversion %d nops %d\n", __func__,
 180                 hdr->minorversion, hdr->nops);
 181         return 0;
 182 }
 183
 184 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 185 {
 186         __be32 *p;
 187         p = read_buf(xdr, 4);
 188         if (unlikely(p == NULL))
 189                 return htonl(NFS4ERR_RESOURCE_HDR);
 190         *op = ntohl(*p);
 191         return 0;
 192 }
 193
 194 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 195 {
 196         __be32 status;
 197
 198         status = decode_fh(xdr, &args->fh);
 199         if (unlikely(status != 0))
 200                 goto out;
 201         args->addr = svc_addr(rqstp);
 202         status = decode_bitmap(xdr, args->bitmap);
 203 out:
 204         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 205         return status;
 206 }
 207
 208 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 209 {
 210         __be32 *p;
 211         __be32 status;
 212
 213         args->addr = svc_addr(rqstp);
 214         status = decode_stateid(xdr, &args->stateid);
 215         if (unlikely(status != 0))
 216                 goto out;
 217         p = read_buf(xdr, 4);
 218         if (unlikely(p == NULL)) {
 219                 status = htonl(NFS4ERR_RESOURCE);
 220                 goto out;
 221         }
 222         args->truncate = ntohl(*p);
 223         status = decode_fh(xdr, &args->fh);
 224 out:
 225         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 226         return status;
 227 }
 228
 229 #if defined(CONFIG_NFS_V4_1)
 230
 231 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 232                                        struct xdr_stream *xdr,
 233                                        struct cb_layoutrecallargs *args)
 234 {
 235         __be32 *p;
 236         __be32 status = 0;
 237         uint32_t iomode;
 238
 239         args->cbl_addr = svc_addr(rqstp);
 240         p = read_buf(xdr, 4 * sizeof(uint32_t));
 241         if (unlikely(p == NULL)) {
 242                 status = htonl(NFS4ERR_BADXDR);
 243                 goto out;
 244         }
 245
 246         args->cbl_layout_type = ntohl(*p++);
 247         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
 248          * as it is unusable and ignored with the other types.
 249          */
 250         iomode = ntohl(*p++);
 251         args->cbl_layoutchanged = ntohl(*p++);
 252         args->cbl_recall_type = ntohl(*p++);
 253
 254         if (args->cbl_recall_type == RETURN_FILE) {
 255                 args->cbl_range.iomode = iomode;
 256                 status = decode_fh(xdr, &args->cbl_fh);
 257                 if (unlikely(status != 0))
 258                         goto out;
 259
 260                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 261                 if (unlikely(p == NULL)) {
 262                         status = htonl(NFS4ERR_BADXDR);
 263                         goto out;
 264                 }
 265                 p = xdr_decode_hyper(p, &args->cbl_range.offset);
 266                 p = xdr_decode_hyper(p, &args->cbl_range.length);
 267                 status = decode_stateid(xdr, &args->cbl_stateid);
 268                 if (unlikely(status != 0))
 269                         goto out;
 270         } else if (args->cbl_recall_type == RETURN_FSID) {
 271                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 272                 if (unlikely(p == NULL)) {
 273                         status = htonl(NFS4ERR_BADXDR);
 274                         goto out;
 275                 }
 276                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
 277                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
 278         } else if (args->cbl_recall_type != RETURN_ALL) {
 279                 status = htonl(NFS4ERR_BADXDR);
 280                 goto out;
 281         }
 282         dprintk("%s: ltype 0x%x iomode %d changed %d recall_type %d\n",
 283                 __func__,
 284                 args->cbl_layout_type, iomode,
 285                 args->cbl_layoutchanged, args->cbl_recall_type);
 286 out:
 287         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 288         return status;
 289 }
 290
 291 static
 292 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 293                                 struct xdr_stream *xdr,
 294                                 struct cb_devicenotifyargs *args)
 295 {
 296         __be32 *p;
 297         __be32 status = 0;
 298         u32 tmp;
 299         int n, i;
 300         args->ndevs = 0;
 301
 302         /* Num of device notifications */
 303         p = read_buf(xdr, sizeof(uint32_t));
 304         if (unlikely(p == NULL)) {
 305                 status = htonl(NFS4ERR_BADXDR);
 306                 goto out;
 307         }
 308         n = ntohl(*p++);
 309         if (n <= 0)
 310                 goto out;
 311         if (n > ULONG_MAX / sizeof(*args->devs)) {
 312                 status = htonl(NFS4ERR_BADXDR);
 313                 goto out;
 314         }
 315
 316         args->devs = kmalloc(n * sizeof(*args->devs), GFP_KERNEL);
 317         if (!args->devs) {
 318                 status = htonl(NFS4ERR_DELAY);
 319                 goto out;
 320         }
 321
 322         /* Decode each dev notification */
 323         for (i = 0; i < n; i++) {
 324                 struct cb_devicenotifyitem *dev = &args->devs[i];
 325
 326                 p = read_buf(xdr, (4 * sizeof(uint32_t)) + NFS4_DEVICEID4_SIZE);
 327                 if (unlikely(p == NULL)) {
 328                         status = htonl(NFS4ERR_BADXDR);
 329                         goto err;
 330                 }
 331
 332                 tmp = ntohl(*p++);      /* bitmap size */
 333                 if (tmp != 1) {
 334                         status = htonl(NFS4ERR_INVAL);
 335                         goto err;
 336                 }
 337                 dev->cbd_notify_type = ntohl(*p++);
 338                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 339                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 340                         status = htonl(NFS4ERR_INVAL);
 341                         goto err;
 342                 }
 343
 344                 tmp = ntohl(*p++);      /* opaque size */
 345                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 346                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 347                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 348                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 349                         status = htonl(NFS4ERR_INVAL);
 350                         goto err;
 351                 }
 352                 dev->cbd_layout_type = ntohl(*p++);
 353                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 354                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 355
 356                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 357                         p = read_buf(xdr, sizeof(uint32_t));
 358                         if (unlikely(p == NULL)) {
 359                                 status = htonl(NFS4ERR_BADXDR);
 360                                 goto err;
 361                         }
 362                         dev->cbd_immediate = ntohl(*p++);
 363                 } else {
 364                         dev->cbd_immediate = 0;
 365                 }
 366
 367                 args->ndevs++;
 368
 369                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 370                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 371                         dev->cbd_immediate);
 372         }
 373 out:
 374         dprintk("%s: status %d ndevs %d\n",
 375                 __func__, ntohl(status), args->ndevs);
 376         return status;
 377 err:
 378         kfree(args->devs);
 379         goto out;
 380 }
 381
 382 static __be32 decode_sessionid(struct xdr_stream *xdr,
 383                                  struct nfs4_sessionid *sid)
 384 {
 385         __be32 *p;
 386         int len = NFS4_MAX_SESSIONID_LEN;
 387
 388         p = read_buf(xdr, len);
 389         if (unlikely(p == NULL))
 390                 return htonl(NFS4ERR_RESOURCE);
 391
 392         memcpy(sid->data, p, len);
 393         return 0;
 394 }
 395
 396 static __be32 decode_rc_list(struct xdr_stream *xdr,
 397                                struct referring_call_list *rc_list)
 398 {
 399         __be32 *p;
 400         int i;
 401         __be32 status;
 402
 403         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 404         if (status)
 405                 goto out;
 406
 407         status = htonl(NFS4ERR_RESOURCE);
 408         p = read_buf(xdr, sizeof(uint32_t));
 409         if (unlikely(p == NULL))
 410                 goto out;
 411
 412         rc_list->rcl_nrefcalls = ntohl(*p++);
 413         if (rc_list->rcl_nrefcalls) {
 414                 p = read_buf(xdr,
 415                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 416                 if (unlikely(p == NULL))
 417                         goto out;
 418                 rc_list->rcl_refcalls = kmalloc(rc_list->rcl_nrefcalls *
 419                                                 sizeof(*rc_list->rcl_refcalls),
 420                                                 GFP_KERNEL);
 421                 if (unlikely(rc_list->rcl_refcalls == NULL))
 422                         goto out;
 423                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 424                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 425                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 426                 }
 427         }
 428         status = 0;
 429
 430 out:
 431         return status;
 432 }
 433
 434 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 435                                         struct xdr_stream *xdr,
 436                                         struct cb_sequenceargs *args)
 437 {
 438         __be32 *p;
 439         int i;
 440         __be32 status;
 441
 442         status = decode_sessionid(xdr, &args->csa_sessionid);
 443         if (status)
 444                 goto out;
 445
 446         status = htonl(NFS4ERR_RESOURCE);
 447         p = read_buf(xdr, 5 * sizeof(uint32_t));
 448         if (unlikely(p == NULL))
 449                 goto out;
 450
 451         args->csa_addr = svc_addr(rqstp);
 452         args->csa_sequenceid = ntohl(*p++);
 453         args->csa_slotid = ntohl(*p++);
 454         args->csa_highestslotid = ntohl(*p++);
 455         args->csa_cachethis = ntohl(*p++);
 456         args->csa_nrclists = ntohl(*p++);
 457         args->csa_rclists = NULL;
 458         if (args->csa_nrclists) {
 459                 args->csa_rclists = kmalloc_array(args->csa_nrclists,
 460                                                   sizeof(*args->csa_rclists),
 461                                                   GFP_KERNEL);
 462                 if (unlikely(args->csa_rclists == NULL))
 463                         goto out;
 464
 465                 for (i = 0; i < args->csa_nrclists; i++) {
 466                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 467                         if (status)
 468                                 goto out_free;
 469                 }
 470         }
 471         status = 0;
 472
 473         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
 474                 "highestslotid %u cachethis %d nrclists %u\n",
 475                 __func__,
 476                 ((u32 *)&args->csa_sessionid)[0],
 477                 ((u32 *)&args->csa_sessionid)[1],
 478                 ((u32 *)&args->csa_sessionid)[2],
 479                 ((u32 *)&args->csa_sessionid)[3],
 480                 args->csa_sequenceid, args->csa_slotid,
 481                 args->csa_highestslotid, args->csa_cachethis,
 482                 args->csa_nrclists);
 483 out:
 484         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 485         return status;
 486
 487 out_free:
 488         for (i = 0; i < args->csa_nrclists; i++)
 489                 kfree(args->csa_rclists[i].rcl_refcalls);
 490         kfree(args->csa_rclists);
 491         goto out;
 492 }
 493
 494 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 495                                       struct xdr_stream *xdr,
 496                                       struct cb_recallanyargs *args)
 497 {
 498         uint32_t bitmap[2];
 499         __be32 *p, status;
 500
 501         args->craa_addr = svc_addr(rqstp);
 502         p = read_buf(xdr, 4);
 503         if (unlikely(p == NULL))
 504                 return htonl(NFS4ERR_BADXDR);
 505         args->craa_objs_to_keep = ntohl(*p++);
 506         status = decode_bitmap(xdr, bitmap);
 507         if (unlikely(status))
 508                 return status;
 509         args->craa_type_mask = bitmap[0];
 510
 511         return 0;
 512 }
 513
 514 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 515                                         struct xdr_stream *xdr,
 516                                         struct cb_recallslotargs *args)
 517 {
 518         __be32 *p;
 519
 520         args->crsa_addr = svc_addr(rqstp);
 521         p = read_buf(xdr, 4);
 522         if (unlikely(p == NULL))
 523                 return htonl(NFS4ERR_BADXDR);
 524         args->crsa_target_highest_slotid = ntohl(*p++);
 525         return 0;
 526 }
 527
 528 #endif /* CONFIG_NFS_V4_1 */
 529
 530 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 531 {
 532         __be32 *p;
 533
 534         p = xdr_reserve_space(xdr, 4 + len);
 535         if (unlikely(p == NULL))
 536                 return htonl(NFS4ERR_RESOURCE);
 537         xdr_encode_opaque(p, str, len);
 538         return 0;
 539 }
 540
 541 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
 542 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
 543 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
 544 {
 545         __be32 bm[2];
 546         __be32 *p;
 547
 548         bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
 549         bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
 550         if (bm[1] != 0) {
 551                 p = xdr_reserve_space(xdr, 16);
 552                 if (unlikely(p == NULL))
 553                         return htonl(NFS4ERR_RESOURCE);
 554                 *p++ = htonl(2);
 555                 *p++ = bm[0];
 556                 *p++ = bm[1];
 557         } else if (bm[0] != 0) {
 558                 p = xdr_reserve_space(xdr, 12);
 559                 if (unlikely(p == NULL))
 560                         return htonl(NFS4ERR_RESOURCE);
 561                 *p++ = htonl(1);
 562                 *p++ = bm[0];
 563         } else {
 564                 p = xdr_reserve_space(xdr, 8);
 565                 if (unlikely(p == NULL))
 566                         return htonl(NFS4ERR_RESOURCE);
 567                 *p++ = htonl(0);
 568         }
 569         *savep = p;
 570         return 0;
 571 }
 572
 573 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 574 {
 575         __be32 *p;
 576
 577         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 578                 return 0;
 579         p = xdr_reserve_space(xdr, 8);
 580         if (unlikely(!p))
 581                 return htonl(NFS4ERR_RESOURCE);
 582         p = xdr_encode_hyper(p, change);
 583         return 0;
 584 }
 585
 586 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 587 {
 588         __be32 *p;
 589
 590         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 591                 return 0;
 592         p = xdr_reserve_space(xdr, 8);
 593         if (unlikely(!p))
 594                 return htonl(NFS4ERR_RESOURCE);
 595         p = xdr_encode_hyper(p, size);
 596         return 0;
 597 }
 598
 599 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 600 {
 601         __be32 *p;
 602
 603         p = xdr_reserve_space(xdr, 12);
 604         if (unlikely(!p))
 605                 return htonl(NFS4ERR_RESOURCE);
 606         p = xdr_encode_hyper(p, time->tv_sec);
 607         *p = htonl(time->tv_nsec);
 608         return 0;
 609 }
 610
 611 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 612 {
 613         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 614                 return 0;
 615         return encode_attr_time(xdr,time);
 616 }
 617
 618 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 619 {
 620         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 621                 return 0;
 622         return encode_attr_time(xdr,time);
 623 }
 624
 625 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 626 {
 627         __be32 status;
 628
 629         hdr->status = xdr_reserve_space(xdr, 4);
 630         if (unlikely(hdr->status == NULL))
 631                 return htonl(NFS4ERR_RESOURCE);
 632         status = encode_string(xdr, hdr->taglen, hdr->tag);
 633         if (unlikely(status != 0))
 634                 return status;
 635         hdr->nops = xdr_reserve_space(xdr, 4);
 636         if (unlikely(hdr->nops == NULL))
 637                 return htonl(NFS4ERR_RESOURCE);
 638         return 0;
 639 }
 640
 641 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 642 {
 643         __be32 *p;
 644
 645         p = xdr_reserve_space(xdr, 8);
 646         if (unlikely(p == NULL))
 647                 return htonl(NFS4ERR_RESOURCE_HDR);
 648         *p++ = htonl(op);
 649         *p = res;
 650         return 0;
 651 }
 652
 653 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 654 {
 655         __be32 *savep = NULL;
 656         __be32 status = res->status;
 657
 658         if (unlikely(status != 0))
 659                 goto out;
 660         status = encode_attr_bitmap(xdr, res->bitmap, &savep);
 661         if (unlikely(status != 0))
 662                 goto out;
 663         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 664         if (unlikely(status != 0))
 665                 goto out;
 666         status = encode_attr_size(xdr, res->bitmap, res->size);
 667         if (unlikely(status != 0))
 668                 goto out;
 669         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 670         if (unlikely(status != 0))
 671                 goto out;
 672         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 673         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 674 out:
 675         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 676         return status;
 677 }
 678
 679 #if defined(CONFIG_NFS_V4_1)
 680
 681 static __be32 encode_sessionid(struct xdr_stream *xdr,
 682                                  const struct nfs4_sessionid *sid)
 683 {
 684         __be32 *p;
 685         int len = NFS4_MAX_SESSIONID_LEN;
 686
 687         p = xdr_reserve_space(xdr, len);
 688         if (unlikely(p == NULL))
 689                 return htonl(NFS4ERR_RESOURCE);
 690
 691         memcpy(p, sid, len);
 692         return 0;
 693 }
 694
 695 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 696                                        struct xdr_stream *xdr,
 697                                        const struct cb_sequenceres *res)
 698 {
 699         __be32 *p;
 700         __be32 status = res->csr_status;
 701
 702         if (unlikely(status != 0))
 703                 goto out;
 704
 705         encode_sessionid(xdr, &res->csr_sessionid);
 706
 707         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 708         if (unlikely(p == NULL))
 709                 return htonl(NFS4ERR_RESOURCE);
 710
 711         *p++ = htonl(res->csr_sequenceid);
 712         *p++ = htonl(res->csr_slotid);
 713         *p++ = htonl(res->csr_highestslotid);
 714         *p++ = htonl(res->csr_target_highestslotid);
 715 out:
 716         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 717         return status;
 718 }
 719
 720 static __be32
 721 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 722 {
 723         if (op_nr == OP_CB_SEQUENCE) {
 724                 if (nop != 0)
 725                         return htonl(NFS4ERR_SEQUENCE_POS);
 726         } else {
 727                 if (nop == 0)
 728                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 729         }
 730
 731         switch (op_nr) {
 732         case OP_CB_GETATTR:
 733         case OP_CB_RECALL:
 734         case OP_CB_SEQUENCE:
 735         case OP_CB_RECALL_ANY:
 736         case OP_CB_RECALL_SLOT:
 737         case OP_CB_LAYOUTRECALL:
 738         case OP_CB_NOTIFY_DEVICEID:
 739                 *op = &callback_ops[op_nr];
 740                 break;
 741
 742         case OP_CB_NOTIFY:
 743         case OP_CB_PUSH_DELEG:
 744         case OP_CB_RECALLABLE_OBJ_AVAIL:
 745         case OP_CB_WANTS_CANCELLED:
 746         case OP_CB_NOTIFY_LOCK:
 747                 return htonl(NFS4ERR_NOTSUPP);
 748
 749         default:
 750                 return htonl(NFS4ERR_OP_ILLEGAL);
 751         }
 752
 753         return htonl(NFS_OK);
 754 }
 755
 756 static void nfs4_callback_free_slot(struct nfs4_session *session)
 757 {
 758         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 759
 760         spin_lock(&tbl->slot_tbl_lock);
 761         /*
 762          * Let the state manager know callback processing done.
 763          * A single slot, so highest used slotid is either 0 or -1
 764          */
 765         tbl->highest_used_slotid = NFS4_NO_SLOT;
 766         nfs4_slot_tbl_drain_complete(tbl);
 767         spin_unlock(&tbl->slot_tbl_lock);
 768 }
 769
 770 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 771 {
 772         if (cps->slotid != NFS4_NO_SLOT)
 773                 nfs4_callback_free_slot(cps->clp->cl_session);
 774 }
 775
 776 #else /* CONFIG_NFS_V4_1 */
 777
 778 static __be32
 779 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 780 {
 781         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 782 }
 783
 784 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 785 {
 786 }
 787 #endif /* CONFIG_NFS_V4_1 */
 788
 789 static __be32
 790 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 791 {
 792         switch (op_nr) {
 793         case OP_CB_GETATTR:
 794         case OP_CB_RECALL:
 795                 *op = &callback_ops[op_nr];
 796                 break;
 797         default:
 798                 return htonl(NFS4ERR_OP_ILLEGAL);
 799         }
 800
 801         return htonl(NFS_OK);
 802 }
 803
 804 static __be32 process_op(uint32_t minorversion, int nop,
 805                 struct svc_rqst *rqstp,
 806                 struct xdr_stream *xdr_in, void *argp,
 807                 struct xdr_stream *xdr_out, void *resp,
 808                 struct cb_process_state *cps)
 809 {
 810         struct callback_op *op = &callback_ops[0];
 811         unsigned int op_nr;
 812         __be32 status;
 813         long maxlen;
 814         __be32 res;
 815
 816         dprintk("%s: start\n", __func__);
 817         status = decode_op_hdr(xdr_in, &op_nr);
 818         if (unlikely(status))
 819                 return status;
 820
 821         dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
 822                 __func__, minorversion, nop, op_nr);
 823
 824         status = minorversion ? preprocess_nfs41_op(nop, op_nr, &op) :
 825                                 preprocess_nfs4_op(op_nr, &op);
 826         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 827                 op_nr = OP_CB_ILLEGAL;
 828         if (status)
 829                 goto encode_hdr;
 830
 831         if (cps->drc_status) {
 832                 status = cps->drc_status;
 833                 goto encode_hdr;
 834         }
 835
 836         maxlen = xdr_out->end - xdr_out->p;
 837         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 838                 status = op->decode_args(rqstp, xdr_in, argp);
 839                 if (likely(status == 0))
 840                         status = op->process_op(argp, resp, cps);
 841         } else
 842                 status = htonl(NFS4ERR_RESOURCE);
 843
 844 encode_hdr:
 845         res = encode_op_hdr(xdr_out, op_nr, status);
 846         if (unlikely(res))
 847                 return res;
 848         if (op->encode_res != NULL && status == 0)
 849                 status = op->encode_res(rqstp, xdr_out, resp);
 850         dprintk("%s: done, status = %d\n", __func__, ntohl(status));
 851         return status;
 852 }
 853
 854 /*
 855  * Decode, process and encode a COMPOUND
 856  */
 857 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 858 {
 859         struct cb_compound_hdr_arg hdr_arg = { 0 };
 860         struct cb_compound_hdr_res hdr_res = { NULL };
 861         struct xdr_stream xdr_in, xdr_out;
 862         __be32 *p, status;
 863         struct cb_process_state cps = {
 864                 .drc_status = 0,
 865                 .clp = NULL,
 866                 .slotid = NFS4_NO_SLOT,
 867                 .net = SVC_NET(rqstp),
 868         };
 869         unsigned int nops = 0;
 870
 871         dprintk("%s: start\n", __func__);
 872
 873         xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
 874
 875         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 876         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 877
 878         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 879         if (status == __constant_htonl(NFS4ERR_RESOURCE))
 880                 return rpc_garbage_args;
 881
 882         if (hdr_arg.minorversion == 0) {
 883                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
 884                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 885                         return rpc_drop_reply;
 886         }
 887
 888         hdr_res.taglen = hdr_arg.taglen;
 889         hdr_res.tag = hdr_arg.tag;
 890         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
 891                 return rpc_system_err;
 892
 893         while (status == 0 && nops != hdr_arg.nops) {
 894                 status = process_op(hdr_arg.minorversion, nops, rqstp,
 895                                     &xdr_in, argp, &xdr_out, resp, &cps);
 896                 nops++;
 897         }
 898
 899         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 900         * resource error in cb_compound status without returning op */
 901         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 902                 status = htonl(NFS4ERR_RESOURCE);
 903                 nops--;
 904         }
 905
 906         *hdr_res.status = status;
 907         *hdr_res.nops = htonl(nops);
 908         nfs4_cb_free_slot(&cps);
 909         nfs_put_client(cps.clp);
 910         dprintk("%s: done, status = %u\n", __func__, ntohl(status));
 911         return rpc_success;
 912 }
 913
 914 /*
 915  * Define NFS4 callback COMPOUND ops.
 916  */
 917 static struct callback_op callback_ops[] = {
 918         [0] = {
 919                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 920         },
 921         [OP_CB_GETATTR] = {
 922                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
 923                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
 924                 .encode_res = (callback_encode_res_t)encode_getattr_res,
 925                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
 926         },
 927         [OP_CB_RECALL] = {
 928                 .process_op = (callback_process_op_t)nfs4_callback_recall,
 929                 .decode_args = (callback_decode_arg_t)decode_recall_args,
 930                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
 931         },
 932 #if defined(CONFIG_NFS_V4_1)
 933         [OP_CB_LAYOUTRECALL] = {
 934                 .process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
 935                 .decode_args =
 936                         (callback_decode_arg_t)decode_layoutrecall_args,
 937                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
 938         },
 939         [OP_CB_NOTIFY_DEVICEID] = {
 940                 .process_op = (callback_process_op_t)nfs4_callback_devicenotify,
 941                 .decode_args =
 942                         (callback_decode_arg_t)decode_devicenotify_args,
 943                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
 944         },
 945         [OP_CB_SEQUENCE] = {
 946                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
 947                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
 948                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
 949                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
 950         },
 951         [OP_CB_RECALL_ANY] = {
 952                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
 953                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
 954                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
 955         },
 956         [OP_CB_RECALL_SLOT] = {
 957                 .process_op = (callback_process_op_t)nfs4_callback_recallslot,
 958                 .decode_args = (callback_decode_arg_t)decode_recallslot_args,
 959                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
 960         },
 961 #endif /* CONFIG_NFS_V4_1 */
 962 };
 963
 964 /*
 965  * Define NFS4 callback procedures
 966  */
 967 static struct svc_procedure nfs4_callback_procedures1[] = {
 968         [CB_NULL] = {
 969                 .pc_func = nfs4_callback_null,
 970                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
 971                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 972                 .pc_xdrressize = 1,
 973         },
 974         [CB_COMPOUND] = {
 975                 .pc_func = nfs4_callback_compound,
 976                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 977                 .pc_argsize = 256,
 978                 .pc_ressize = 256,
 979                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
 980         }
 981 };
 982
 983 struct svc_version nfs4_callback_version1 = {
 984         .vs_vers = 1,
 985         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 986         .vs_proc = nfs4_callback_procedures1,
 987         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 988         .vs_dispatch = NULL,
 989         .vs_hidden = 1,
 990 };
 991
 992 struct svc_version nfs4_callback_version4 = {
 993         .vs_vers = 4,
 994         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 995         .vs_proc = nfs4_callback_procedures1,
 996         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 997         .vs_dispatch = NULL,
 998         .vs_hidden = 1,
 999 };