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/slab.h>
  13 #include <linux/sunrpc/bc_xprt.h>
  14 #include "nfs4_fs.h"
  15 #include "callback.h"
  16 #include "internal.h"
  17
  18 #define CB_OP_TAGLEN_MAXSZ      (512)
  19 #define CB_OP_HDR_RES_MAXSZ     (2 + CB_OP_TAGLEN_MAXSZ)
  20 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4)
  21 #define CB_OP_GETATTR_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ + \
  22                                 CB_OP_GETATTR_BITMAP_MAXSZ + \
  23                                 2 + 2 + 3 + 3)
  24 #define CB_OP_RECALL_RES_MAXSZ  (CB_OP_HDR_RES_MAXSZ)
  25
  26 #if defined(CONFIG_NFS_V4_1)
  27 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  28 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  29 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  30                                         4 + 1 + 3)
  31 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  32 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  33 #endif /* CONFIG_NFS_V4_1 */
  34
  35 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  36
  37 /* Internal error code */
  38 #define NFS4ERR_RESOURCE_HDR    11050
  39
  40 typedef __be32 (*callback_process_op_t)(void *, void *,
  41                                         struct cb_process_state *);
  42 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  43 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  44
  45
  46 struct callback_op {
  47         callback_process_op_t process_op;
  48         callback_decode_arg_t decode_args;
  49         callback_encode_res_t encode_res;
  50         long res_maxsize;
  51 };
  52
  53 static struct callback_op callback_ops[];
  54
  55 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  56 {
  57         return htonl(NFS4_OK);
  58 }
  59
  60 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  61 {
  62         return xdr_argsize_check(rqstp, p);
  63 }
  64
  65 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  66 {
  67         return xdr_ressize_check(rqstp, p);
  68 }
  69
  70 static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
  71 {
  72         __be32 *p;
  73
  74         p = xdr_inline_decode(xdr, nbytes);
  75         if (unlikely(p == NULL))
  76                 printk(KERN_WARNING "NFSv4 callback reply buffer overflowed!\n");
  77         return p;
  78 }
  79
  80 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
  81 {
  82         __be32 *p;
  83
  84         p = read_buf(xdr, 4);
  85         if (unlikely(p == NULL))
  86                 return htonl(NFS4ERR_RESOURCE);
  87         *len = ntohl(*p);
  88
  89         if (*len != 0) {
  90                 p = read_buf(xdr, *len);
  91                 if (unlikely(p == NULL))
  92                         return htonl(NFS4ERR_RESOURCE);
  93                 *str = (const char *)p;
  94         } else
  95                 *str = NULL;
  96
  97         return 0;
  98 }
  99
 100 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
 101 {
 102         __be32 *p;
 103
 104         p = read_buf(xdr, 4);
 105         if (unlikely(p == NULL))
 106                 return htonl(NFS4ERR_RESOURCE);
 107         fh->size = ntohl(*p);
 108         if (fh->size > NFS4_FHSIZE)
 109                 return htonl(NFS4ERR_BADHANDLE);
 110         p = read_buf(xdr, fh->size);
 111         if (unlikely(p == NULL))
 112                 return htonl(NFS4ERR_RESOURCE);
 113         memcpy(&fh->data[0], p, fh->size);
 114         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 115         return 0;
 116 }
 117
 118 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 119 {
 120         __be32 *p;
 121         unsigned int attrlen;
 122
 123         p = read_buf(xdr, 4);
 124         if (unlikely(p == NULL))
 125                 return htonl(NFS4ERR_RESOURCE);
 126         attrlen = ntohl(*p);
 127         p = read_buf(xdr, attrlen << 2);
 128         if (unlikely(p == NULL))
 129                 return htonl(NFS4ERR_RESOURCE);
 130         if (likely(attrlen > 0))
 131                 bitmap[0] = ntohl(*p++);
 132         if (attrlen > 1)
 133                 bitmap[1] = ntohl(*p);
 134         return 0;
 135 }
 136
 137 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 138 {
 139         __be32 *p;
 140
 141         p = read_buf(xdr, 16);
 142         if (unlikely(p == NULL))
 143                 return htonl(NFS4ERR_RESOURCE);
 144         memcpy(stateid->data, p, 16);
 145         return 0;
 146 }
 147
 148 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 149 {
 150         __be32 *p;
 151         __be32 status;
 152
 153         status = decode_string(xdr, &hdr->taglen, &hdr->tag);
 154         if (unlikely(status != 0))
 155                 return status;
 156         /* We do not like overly long tags! */
 157         if (hdr->taglen > CB_OP_TAGLEN_MAXSZ - 12) {
 158                 printk("NFSv4 CALLBACK %s: client sent tag of length %u\n",
 159                                 __func__, hdr->taglen);
 160                 return htonl(NFS4ERR_RESOURCE);
 161         }
 162         p = read_buf(xdr, 12);
 163         if (unlikely(p == NULL))
 164                 return htonl(NFS4ERR_RESOURCE);
 165         hdr->minorversion = ntohl(*p++);
 166         /* Check minor version is zero or one. */
 167         if (hdr->minorversion <= 1) {
 168                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 */
 169         } else {
 170                 printk(KERN_WARNING "%s: NFSv4 server callback with "
 171                         "illegal minor version %u!\n",
 172                         __func__, hdr->minorversion);
 173                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 174         }
 175         hdr->nops = ntohl(*p);
 176         dprintk("%s: minorversion %d nops %d\n", __func__,
 177                 hdr->minorversion, hdr->nops);
 178         return 0;
 179 }
 180
 181 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 182 {
 183         __be32 *p;
 184         p = read_buf(xdr, 4);
 185         if (unlikely(p == NULL))
 186                 return htonl(NFS4ERR_RESOURCE_HDR);
 187         *op = ntohl(*p);
 188         return 0;
 189 }
 190
 191 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 192 {
 193         __be32 status;
 194
 195         status = decode_fh(xdr, &args->fh);
 196         if (unlikely(status != 0))
 197                 goto out;
 198         args->addr = svc_addr(rqstp);
 199         status = decode_bitmap(xdr, args->bitmap);
 200 out:
 201         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 202         return status;
 203 }
 204
 205 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 206 {
 207         __be32 *p;
 208         __be32 status;
 209
 210         args->addr = svc_addr(rqstp);
 211         status = decode_stateid(xdr, &args->stateid);
 212         if (unlikely(status != 0))
 213                 goto out;
 214         p = read_buf(xdr, 4);
 215         if (unlikely(p == NULL)) {
 216                 status = htonl(NFS4ERR_RESOURCE);
 217                 goto out;
 218         }
 219         args->truncate = ntohl(*p);
 220         status = decode_fh(xdr, &args->fh);
 221 out:
 222         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 223         return status;
 224 }
 225
 226 #if defined(CONFIG_NFS_V4_1)
 227
 228 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 229                                        struct xdr_stream *xdr,
 230                                        struct cb_layoutrecallargs *args)
 231 {
 232         __be32 *p;
 233         __be32 status = 0;
 234         uint32_t iomode;
 235
 236         args->cbl_addr = svc_addr(rqstp);
 237         p = read_buf(xdr, 4 * sizeof(uint32_t));
 238         if (unlikely(p == NULL)) {
 239                 status = htonl(NFS4ERR_BADXDR);
 240                 goto out;
 241         }
 242
 243         args->cbl_layout_type = ntohl(*p++);
 244         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
 245          * as it is unusable and ignored with the other types.
 246          */
 247         iomode = ntohl(*p++);
 248         args->cbl_layoutchanged = ntohl(*p++);
 249         args->cbl_recall_type = ntohl(*p++);
 250
 251         if (args->cbl_recall_type == RETURN_FILE) {
 252                 args->cbl_range.iomode = iomode;
 253                 status = decode_fh(xdr, &args->cbl_fh);
 254                 if (unlikely(status != 0))
 255                         goto out;
 256
 257                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 258                 if (unlikely(p == NULL)) {
 259                         status = htonl(NFS4ERR_BADXDR);
 260                         goto out;
 261                 }
 262                 p = xdr_decode_hyper(p, &args->cbl_range.offset);
 263                 p = xdr_decode_hyper(p, &args->cbl_range.length);
 264                 status = decode_stateid(xdr, &args->cbl_stateid);
 265                 if (unlikely(status != 0))
 266                         goto out;
 267         } else if (args->cbl_recall_type == RETURN_FSID) {
 268                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 269                 if (unlikely(p == NULL)) {
 270                         status = htonl(NFS4ERR_BADXDR);
 271                         goto out;
 272                 }
 273                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
 274                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
 275         } else if (args->cbl_recall_type != RETURN_ALL) {
 276                 status = htonl(NFS4ERR_BADXDR);
 277                 goto out;
 278         }
 279         dprintk("%s: ltype 0x%x iomode %d changed %d recall_type %d\n",
 280                 __func__,
 281                 args->cbl_layout_type, iomode,
 282                 args->cbl_layoutchanged, args->cbl_recall_type);
 283 out:
 284         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 285         return status;
 286 }
 287
 288 static
 289 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 290                                 struct xdr_stream *xdr,
 291                                 struct cb_devicenotifyargs *args)
 292 {
 293         __be32 *p;
 294         __be32 status = 0;
 295         u32 tmp;
 296         int n, i;
 297         args->ndevs = 0;
 298
 299         /* Num of device notifications */
 300         p = read_buf(xdr, sizeof(uint32_t));
 301         if (unlikely(p == NULL)) {
 302                 status = htonl(NFS4ERR_BADXDR);
 303                 goto out;
 304         }
 305         n = ntohl(*p++);
 306         if (n <= 0)
 307                 goto out;
 308
 309         args->devs = kmalloc(n * sizeof(*args->devs), GFP_KERNEL);
 310         if (!args->devs) {
 311                 status = htonl(NFS4ERR_DELAY);
 312                 goto out;
 313         }
 314
 315         /* Decode each dev notification */
 316         for (i = 0; i < n; i++) {
 317                 struct cb_devicenotifyitem *dev = &args->devs[i];
 318
 319                 p = read_buf(xdr, (4 * sizeof(uint32_t)) + NFS4_DEVICEID4_SIZE);
 320                 if (unlikely(p == NULL)) {
 321                         status = htonl(NFS4ERR_BADXDR);
 322                         goto err;
 323                 }
 324
 325                 tmp = ntohl(*p++);      /* bitmap size */
 326                 if (tmp != 1) {
 327                         status = htonl(NFS4ERR_INVAL);
 328                         goto err;
 329                 }
 330                 dev->cbd_notify_type = ntohl(*p++);
 331                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 332                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 333                         status = htonl(NFS4ERR_INVAL);
 334                         goto err;
 335                 }
 336
 337                 tmp = ntohl(*p++);      /* opaque size */
 338                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 339                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 340                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 341                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 342                         status = htonl(NFS4ERR_INVAL);
 343                         goto err;
 344                 }
 345                 dev->cbd_layout_type = ntohl(*p++);
 346                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 347                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 348
 349                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 350                         p = read_buf(xdr, sizeof(uint32_t));
 351                         if (unlikely(p == NULL)) {
 352                                 status = htonl(NFS4ERR_BADXDR);
 353                                 goto err;
 354                         }
 355                         dev->cbd_immediate = ntohl(*p++);
 356                 } else {
 357                         dev->cbd_immediate = 0;
 358                 }
 359
 360                 args->ndevs++;
 361
 362                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 363                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 364                         dev->cbd_immediate);
 365         }
 366 out:
 367         dprintk("%s: status %d ndevs %d\n",
 368                 __func__, ntohl(status), args->ndevs);
 369         return status;
 370 err:
 371         kfree(args->devs);
 372         goto out;
 373 }
 374
 375 static __be32 decode_sessionid(struct xdr_stream *xdr,
 376                                  struct nfs4_sessionid *sid)
 377 {
 378         __be32 *p;
 379         int len = NFS4_MAX_SESSIONID_LEN;
 380
 381         p = read_buf(xdr, len);
 382         if (unlikely(p == NULL))
 383                 return htonl(NFS4ERR_RESOURCE);
 384
 385         memcpy(sid->data, p, len);
 386         return 0;
 387 }
 388
 389 static __be32 decode_rc_list(struct xdr_stream *xdr,
 390                                struct referring_call_list *rc_list)
 391 {
 392         __be32 *p;
 393         int i;
 394         __be32 status;
 395
 396         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 397         if (status)
 398                 goto out;
 399
 400         status = htonl(NFS4ERR_RESOURCE);
 401         p = read_buf(xdr, sizeof(uint32_t));
 402         if (unlikely(p == NULL))
 403                 goto out;
 404
 405         rc_list->rcl_nrefcalls = ntohl(*p++);
 406         if (rc_list->rcl_nrefcalls) {
 407                 p = read_buf(xdr,
 408                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 409                 if (unlikely(p == NULL))
 410                         goto out;
 411                 rc_list->rcl_refcalls = kmalloc(rc_list->rcl_nrefcalls *
 412                                                 sizeof(*rc_list->rcl_refcalls),
 413                                                 GFP_KERNEL);
 414                 if (unlikely(rc_list->rcl_refcalls == NULL))
 415                         goto out;
 416                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 417                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 418                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 419                 }
 420         }
 421         status = 0;
 422
 423 out:
 424         return status;
 425 }
 426
 427 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 428                                         struct xdr_stream *xdr,
 429                                         struct cb_sequenceargs *args)
 430 {
 431         __be32 *p;
 432         int i;
 433         __be32 status;
 434
 435         status = decode_sessionid(xdr, &args->csa_sessionid);
 436         if (status)
 437                 goto out;
 438
 439         status = htonl(NFS4ERR_RESOURCE);
 440         p = read_buf(xdr, 5 * sizeof(uint32_t));
 441         if (unlikely(p == NULL))
 442                 goto out;
 443
 444         args->csa_addr = svc_addr(rqstp);
 445         args->csa_sequenceid = ntohl(*p++);
 446         args->csa_slotid = ntohl(*p++);
 447         args->csa_highestslotid = ntohl(*p++);
 448         args->csa_cachethis = ntohl(*p++);
 449         args->csa_nrclists = ntohl(*p++);
 450         args->csa_rclists = NULL;
 451         if (args->csa_nrclists) {
 452                 args->csa_rclists = kmalloc(args->csa_nrclists *
 453                                             sizeof(*args->csa_rclists),
 454                                             GFP_KERNEL);
 455                 if (unlikely(args->csa_rclists == NULL))
 456                         goto out;
 457
 458                 for (i = 0; i < args->csa_nrclists; i++) {
 459                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 460                         if (status)
 461                                 goto out_free;
 462                 }
 463         }
 464         status = 0;
 465
 466         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
 467                 "highestslotid %u cachethis %d nrclists %u\n",
 468                 __func__,
 469                 ((u32 *)&args->csa_sessionid)[0],
 470                 ((u32 *)&args->csa_sessionid)[1],
 471                 ((u32 *)&args->csa_sessionid)[2],
 472                 ((u32 *)&args->csa_sessionid)[3],
 473                 args->csa_sequenceid, args->csa_slotid,
 474                 args->csa_highestslotid, args->csa_cachethis,
 475                 args->csa_nrclists);
 476 out:
 477         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 478         return status;
 479
 480 out_free:
 481         for (i = 0; i < args->csa_nrclists; i++)
 482                 kfree(args->csa_rclists[i].rcl_refcalls);
 483         kfree(args->csa_rclists);
 484         goto out;
 485 }
 486
 487 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 488                                       struct xdr_stream *xdr,
 489                                       struct cb_recallanyargs *args)
 490 {
 491         uint32_t bitmap[2];
 492         __be32 *p, status;
 493
 494         args->craa_addr = svc_addr(rqstp);
 495         p = read_buf(xdr, 4);
 496         if (unlikely(p == NULL))
 497                 return htonl(NFS4ERR_BADXDR);
 498         args->craa_objs_to_keep = ntohl(*p++);
 499         status = decode_bitmap(xdr, bitmap);
 500         if (unlikely(status))
 501                 return status;
 502         args->craa_type_mask = bitmap[0];
 503
 504         return 0;
 505 }
 506
 507 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 508                                         struct xdr_stream *xdr,
 509                                         struct cb_recallslotargs *args)
 510 {
 511         __be32 *p;
 512
 513         args->crsa_addr = svc_addr(rqstp);
 514         p = read_buf(xdr, 4);
 515         if (unlikely(p == NULL))
 516                 return htonl(NFS4ERR_BADXDR);
 517         args->crsa_target_max_slots = ntohl(*p++);
 518         return 0;
 519 }
 520
 521 #endif /* CONFIG_NFS_V4_1 */
 522
 523 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 524 {
 525         __be32 *p;
 526
 527         p = xdr_reserve_space(xdr, 4 + len);
 528         if (unlikely(p == NULL))
 529                 return htonl(NFS4ERR_RESOURCE);
 530         xdr_encode_opaque(p, str, len);
 531         return 0;
 532 }
 533
 534 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
 535 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
 536 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
 537 {
 538         __be32 bm[2];
 539         __be32 *p;
 540
 541         bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
 542         bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
 543         if (bm[1] != 0) {
 544                 p = xdr_reserve_space(xdr, 16);
 545                 if (unlikely(p == NULL))
 546                         return htonl(NFS4ERR_RESOURCE);
 547                 *p++ = htonl(2);
 548                 *p++ = bm[0];
 549                 *p++ = bm[1];
 550         } else if (bm[0] != 0) {
 551                 p = xdr_reserve_space(xdr, 12);
 552                 if (unlikely(p == NULL))
 553                         return htonl(NFS4ERR_RESOURCE);
 554                 *p++ = htonl(1);
 555                 *p++ = bm[0];
 556         } else {
 557                 p = xdr_reserve_space(xdr, 8);
 558                 if (unlikely(p == NULL))
 559                         return htonl(NFS4ERR_RESOURCE);
 560                 *p++ = htonl(0);
 561         }
 562         *savep = p;
 563         return 0;
 564 }
 565
 566 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 567 {
 568         __be32 *p;
 569
 570         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 571                 return 0;
 572         p = xdr_reserve_space(xdr, 8);
 573         if (unlikely(!p))
 574                 return htonl(NFS4ERR_RESOURCE);
 575         p = xdr_encode_hyper(p, change);
 576         return 0;
 577 }
 578
 579 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 580 {
 581         __be32 *p;
 582
 583         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 584                 return 0;
 585         p = xdr_reserve_space(xdr, 8);
 586         if (unlikely(!p))
 587                 return htonl(NFS4ERR_RESOURCE);
 588         p = xdr_encode_hyper(p, size);
 589         return 0;
 590 }
 591
 592 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 593 {
 594         __be32 *p;
 595
 596         p = xdr_reserve_space(xdr, 12);
 597         if (unlikely(!p))
 598                 return htonl(NFS4ERR_RESOURCE);
 599         p = xdr_encode_hyper(p, time->tv_sec);
 600         *p = htonl(time->tv_nsec);
 601         return 0;
 602 }
 603
 604 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 605 {
 606         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 607                 return 0;
 608         return encode_attr_time(xdr,time);
 609 }
 610
 611 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 612 {
 613         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 614                 return 0;
 615         return encode_attr_time(xdr,time);
 616 }
 617
 618 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 619 {
 620         __be32 status;
 621
 622         hdr->status = xdr_reserve_space(xdr, 4);
 623         if (unlikely(hdr->status == NULL))
 624                 return htonl(NFS4ERR_RESOURCE);
 625         status = encode_string(xdr, hdr->taglen, hdr->tag);
 626         if (unlikely(status != 0))
 627                 return status;
 628         hdr->nops = xdr_reserve_space(xdr, 4);
 629         if (unlikely(hdr->nops == NULL))
 630                 return htonl(NFS4ERR_RESOURCE);
 631         return 0;
 632 }
 633
 634 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 635 {
 636         __be32 *p;
 637
 638         p = xdr_reserve_space(xdr, 8);
 639         if (unlikely(p == NULL))
 640                 return htonl(NFS4ERR_RESOURCE_HDR);
 641         *p++ = htonl(op);
 642         *p = res;
 643         return 0;
 644 }
 645
 646 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 647 {
 648         __be32 *savep = NULL;
 649         __be32 status = res->status;
 650
 651         if (unlikely(status != 0))
 652                 goto out;
 653         status = encode_attr_bitmap(xdr, res->bitmap, &savep);
 654         if (unlikely(status != 0))
 655                 goto out;
 656         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 657         if (unlikely(status != 0))
 658                 goto out;
 659         status = encode_attr_size(xdr, res->bitmap, res->size);
 660         if (unlikely(status != 0))
 661                 goto out;
 662         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 663         if (unlikely(status != 0))
 664                 goto out;
 665         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 666         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 667 out:
 668         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 669         return status;
 670 }
 671
 672 #if defined(CONFIG_NFS_V4_1)
 673
 674 static __be32 encode_sessionid(struct xdr_stream *xdr,
 675                                  const struct nfs4_sessionid *sid)
 676 {
 677         __be32 *p;
 678         int len = NFS4_MAX_SESSIONID_LEN;
 679
 680         p = xdr_reserve_space(xdr, len);
 681         if (unlikely(p == NULL))
 682                 return htonl(NFS4ERR_RESOURCE);
 683
 684         memcpy(p, sid, len);
 685         return 0;
 686 }
 687
 688 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 689                                        struct xdr_stream *xdr,
 690                                        const struct cb_sequenceres *res)
 691 {
 692         __be32 *p;
 693         unsigned status = res->csr_status;
 694
 695         if (unlikely(status != 0))
 696                 goto out;
 697
 698         encode_sessionid(xdr, &res->csr_sessionid);
 699
 700         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 701         if (unlikely(p == NULL))
 702                 return htonl(NFS4ERR_RESOURCE);
 703
 704         *p++ = htonl(res->csr_sequenceid);
 705         *p++ = htonl(res->csr_slotid);
 706         *p++ = htonl(res->csr_highestslotid);
 707         *p++ = htonl(res->csr_target_highestslotid);
 708 out:
 709         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 710         return status;
 711 }
 712
 713 static __be32
 714 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 715 {
 716         if (op_nr == OP_CB_SEQUENCE) {
 717                 if (nop != 0)
 718                         return htonl(NFS4ERR_SEQUENCE_POS);
 719         } else {
 720                 if (nop == 0)
 721                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 722         }
 723
 724         switch (op_nr) {
 725         case OP_CB_GETATTR:
 726         case OP_CB_RECALL:
 727         case OP_CB_SEQUENCE:
 728         case OP_CB_RECALL_ANY:
 729         case OP_CB_RECALL_SLOT:
 730         case OP_CB_LAYOUTRECALL:
 731         case OP_CB_NOTIFY_DEVICEID:
 732                 *op = &callback_ops[op_nr];
 733                 break;
 734
 735         case OP_CB_NOTIFY:
 736         case OP_CB_PUSH_DELEG:
 737         case OP_CB_RECALLABLE_OBJ_AVAIL:
 738         case OP_CB_WANTS_CANCELLED:
 739         case OP_CB_NOTIFY_LOCK:
 740                 return htonl(NFS4ERR_NOTSUPP);
 741
 742         default:
 743                 return htonl(NFS4ERR_OP_ILLEGAL);
 744         }
 745
 746         return htonl(NFS_OK);
 747 }
 748
 749 static void nfs4_callback_free_slot(struct nfs4_session *session)
 750 {
 751         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 752
 753         spin_lock(&tbl->slot_tbl_lock);
 754         /*
 755          * Let the state manager know callback processing done.
 756          * A single slot, so highest used slotid is either 0 or -1
 757          */
 758         tbl->highest_used_slotid = -1;
 759         nfs4_check_drain_bc_complete(session);
 760         spin_unlock(&tbl->slot_tbl_lock);
 761 }
 762
 763 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 764 {
 765         if (cps->slotid != -1)
 766                 nfs4_callback_free_slot(cps->clp->cl_session);
 767 }
 768
 769 #else /* CONFIG_NFS_V4_1 */
 770
 771 static __be32
 772 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 773 {
 774         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 775 }
 776
 777 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 778 {
 779 }
 780 #endif /* CONFIG_NFS_V4_1 */
 781
 782 static __be32
 783 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 784 {
 785         switch (op_nr) {
 786         case OP_CB_GETATTR:
 787         case OP_CB_RECALL:
 788                 *op = &callback_ops[op_nr];
 789                 break;
 790         default:
 791                 return htonl(NFS4ERR_OP_ILLEGAL);
 792         }
 793
 794         return htonl(NFS_OK);
 795 }
 796
 797 static __be32 process_op(uint32_t minorversion, int nop,
 798                 struct svc_rqst *rqstp,
 799                 struct xdr_stream *xdr_in, void *argp,
 800                 struct xdr_stream *xdr_out, void *resp,
 801                 struct cb_process_state *cps)
 802 {
 803         struct callback_op *op = &callback_ops[0];
 804         unsigned int op_nr;
 805         __be32 status;
 806         long maxlen;
 807         __be32 res;
 808
 809         dprintk("%s: start\n", __func__);
 810         status = decode_op_hdr(xdr_in, &op_nr);
 811         if (unlikely(status))
 812                 return status;
 813
 814         dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
 815                 __func__, minorversion, nop, op_nr);
 816
 817         status = minorversion ? preprocess_nfs41_op(nop, op_nr, &op) :
 818                                 preprocess_nfs4_op(op_nr, &op);
 819         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 820                 op_nr = OP_CB_ILLEGAL;
 821         if (status)
 822                 goto encode_hdr;
 823
 824         if (cps->drc_status) {
 825                 status = cps->drc_status;
 826                 goto encode_hdr;
 827         }
 828
 829         maxlen = xdr_out->end - xdr_out->p;
 830         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 831                 status = op->decode_args(rqstp, xdr_in, argp);
 832                 if (likely(status == 0))
 833                         status = op->process_op(argp, resp, cps);
 834         } else
 835                 status = htonl(NFS4ERR_RESOURCE);
 836
 837 encode_hdr:
 838         res = encode_op_hdr(xdr_out, op_nr, status);
 839         if (unlikely(res))
 840                 return res;
 841         if (op->encode_res != NULL && status == 0)
 842                 status = op->encode_res(rqstp, xdr_out, resp);
 843         dprintk("%s: done, status = %d\n", __func__, ntohl(status));
 844         return status;
 845 }
 846
 847 /*
 848  * Decode, process and encode a COMPOUND
 849  */
 850 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 851 {
 852         struct cb_compound_hdr_arg hdr_arg = { 0 };
 853         struct cb_compound_hdr_res hdr_res = { NULL };
 854         struct xdr_stream xdr_in, xdr_out;
 855         __be32 *p, status;
 856         struct cb_process_state cps = {
 857                 .drc_status = 0,
 858                 .clp = NULL,
 859                 .slotid = -1,
 860         };
 861         unsigned int nops = 0;
 862
 863         dprintk("%s: start\n", __func__);
 864
 865         xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
 866
 867         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 868         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 869
 870         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 871         if (status == __constant_htonl(NFS4ERR_RESOURCE))
 872                 return rpc_garbage_args;
 873
 874         if (hdr_arg.minorversion == 0) {
 875                 cps.clp = nfs4_find_client_ident(hdr_arg.cb_ident);
 876                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 877                         return rpc_drop_reply;
 878         }
 879
 880         hdr_res.taglen = hdr_arg.taglen;
 881         hdr_res.tag = hdr_arg.tag;
 882         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
 883                 return rpc_system_err;
 884
 885         while (status == 0 && nops != hdr_arg.nops) {
 886                 status = process_op(hdr_arg.minorversion, nops, rqstp,
 887                                     &xdr_in, argp, &xdr_out, resp, &cps);
 888                 nops++;
 889         }
 890
 891         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 892         * resource error in cb_compound status without returning op */
 893         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 894                 status = htonl(NFS4ERR_RESOURCE);
 895                 nops--;
 896         }
 897
 898         *hdr_res.status = status;
 899         *hdr_res.nops = htonl(nops);
 900         nfs4_cb_free_slot(&cps);
 901         nfs_put_client(cps.clp);
 902         dprintk("%s: done, status = %u\n", __func__, ntohl(status));
 903         return rpc_success;
 904 }
 905
 906 /*
 907  * Define NFS4 callback COMPOUND ops.
 908  */
 909 static struct callback_op callback_ops[] = {
 910         [0] = {
 911                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 912         },
 913         [OP_CB_GETATTR] = {
 914                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
 915                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
 916                 .encode_res = (callback_encode_res_t)encode_getattr_res,
 917                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
 918         },
 919         [OP_CB_RECALL] = {
 920                 .process_op = (callback_process_op_t)nfs4_callback_recall,
 921                 .decode_args = (callback_decode_arg_t)decode_recall_args,
 922                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
 923         },
 924 #if defined(CONFIG_NFS_V4_1)
 925         [OP_CB_LAYOUTRECALL] = {
 926                 .process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
 927                 .decode_args =
 928                         (callback_decode_arg_t)decode_layoutrecall_args,
 929                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
 930         },
 931         [OP_CB_NOTIFY_DEVICEID] = {
 932                 .process_op = (callback_process_op_t)nfs4_callback_devicenotify,
 933                 .decode_args =
 934                         (callback_decode_arg_t)decode_devicenotify_args,
 935                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
 936         },
 937         [OP_CB_SEQUENCE] = {
 938                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
 939                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
 940                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
 941                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
 942         },
 943         [OP_CB_RECALL_ANY] = {
 944                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
 945                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
 946                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
 947         },
 948         [OP_CB_RECALL_SLOT] = {
 949                 .process_op = (callback_process_op_t)nfs4_callback_recallslot,
 950                 .decode_args = (callback_decode_arg_t)decode_recallslot_args,
 951                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
 952         },
 953 #endif /* CONFIG_NFS_V4_1 */
 954 };
 955
 956 /*
 957  * Define NFS4 callback procedures
 958  */
 959 static struct svc_procedure nfs4_callback_procedures1[] = {
 960         [CB_NULL] = {
 961                 .pc_func = nfs4_callback_null,
 962                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
 963                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 964                 .pc_xdrressize = 1,
 965         },
 966         [CB_COMPOUND] = {
 967                 .pc_func = nfs4_callback_compound,
 968                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
 969                 .pc_argsize = 256,
 970                 .pc_ressize = 256,
 971                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
 972         }
 973 };
 974
 975 struct svc_version nfs4_callback_version1 = {
 976         .vs_vers = 1,
 977         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 978         .vs_proc = nfs4_callback_procedures1,
 979         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 980         .vs_dispatch = NULL,
 981         .vs_hidden = 1,
 982 };
 983
 984 struct svc_version nfs4_callback_version4 = {
 985         .vs_vers = 4,
 986         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
 987         .vs_proc = nfs4_callback_procedures1,
 988         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
 989         .vs_dispatch = NULL,
 990         .vs_hidden = 1,
 991 };