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 * 4) // opcode, status
  23 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4 * 4) // bitmap length, 3 bitmaps
  24 #define CB_OP_GETATTR_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ + \
  25                                          CB_OP_GETATTR_BITMAP_MAXSZ + \
  26                                          /* change, size, ctime, mtime */\
  27                                          (2 + 2 + 3 + 3) * 4)
  28 #define CB_OP_RECALL_RES_MAXSZ          (CB_OP_HDR_RES_MAXSZ)
  29
  30 #if defined(CONFIG_NFS_V4_1)
  31 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  32 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
  33 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
  34                                          NFS4_MAX_SESSIONID_LEN + \
  35                                          (1 + 3) * 4) // seqid, 3 slotids
  36 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
  37 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
  38 #endif /* CONFIG_NFS_V4_1 */
  39
  40 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  41
  42 /* Internal error code */
  43 #define NFS4ERR_RESOURCE_HDR    11050
  44
  45 typedef __be32 (*callback_process_op_t)(void *, void *,
  46                                         struct cb_process_state *);
  47 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
  48 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
  49
  50
  51 struct callback_op {
  52         callback_process_op_t process_op;
  53         callback_decode_arg_t decode_args;
  54         callback_encode_res_t encode_res;
  55         long res_maxsize;
  56 };
  57
  58 static struct callback_op callback_ops[];
  59
  60 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
  61 {
  62         return htonl(NFS4_OK);
  63 }
  64
  65 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  66 {
  67         return xdr_argsize_check(rqstp, p);
  68 }
  69
  70 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
  71 {
  72         return xdr_ressize_check(rqstp, p);
  73 }
  74
  75 static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
  76 {
  77         __be32 *p;
  78
  79         p = xdr_inline_decode(xdr, nbytes);
  80         if (unlikely(p == NULL))
  81                 printk(KERN_WARNING "NFS: NFSv4 callback reply buffer overflowed!\n");
  82         return p;
  83 }
  84
  85 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
  86 {
  87         __be32 *p;
  88
  89         p = read_buf(xdr, 4);
  90         if (unlikely(p == NULL))
  91                 return htonl(NFS4ERR_RESOURCE);
  92         *len = ntohl(*p);
  93
  94         if (*len != 0) {
  95                 p = read_buf(xdr, *len);
  96                 if (unlikely(p == NULL))
  97                         return htonl(NFS4ERR_RESOURCE);
  98                 *str = (const char *)p;
  99         } else
 100                 *str = NULL;
 101
 102         return 0;
 103 }
 104
 105 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
 106 {
 107         __be32 *p;
 108
 109         p = read_buf(xdr, 4);
 110         if (unlikely(p == NULL))
 111                 return htonl(NFS4ERR_RESOURCE);
 112         fh->size = ntohl(*p);
 113         if (fh->size > NFS4_FHSIZE)
 114                 return htonl(NFS4ERR_BADHANDLE);
 115         p = read_buf(xdr, fh->size);
 116         if (unlikely(p == NULL))
 117                 return htonl(NFS4ERR_RESOURCE);
 118         memcpy(&fh->data[0], p, fh->size);
 119         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
 120         return 0;
 121 }
 122
 123 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
 124 {
 125         __be32 *p;
 126         unsigned int attrlen;
 127
 128         p = read_buf(xdr, 4);
 129         if (unlikely(p == NULL))
 130                 return htonl(NFS4ERR_RESOURCE);
 131         attrlen = ntohl(*p);
 132         p = read_buf(xdr, attrlen << 2);
 133         if (unlikely(p == NULL))
 134                 return htonl(NFS4ERR_RESOURCE);
 135         if (likely(attrlen > 0))
 136                 bitmap[0] = ntohl(*p++);
 137         if (attrlen > 1)
 138                 bitmap[1] = ntohl(*p);
 139         return 0;
 140 }
 141
 142 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 143 {
 144         __be32 *p;
 145
 146         p = read_buf(xdr, NFS4_STATEID_SIZE);
 147         if (unlikely(p == NULL))
 148                 return htonl(NFS4ERR_RESOURCE);
 149         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
 150         return 0;
 151 }
 152
 153 static __be32 decode_delegation_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 154 {
 155         stateid->type = NFS4_DELEGATION_STATEID_TYPE;
 156         return decode_stateid(xdr, stateid);
 157 }
 158
 159 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
 160 {
 161         __be32 *p;
 162         __be32 status;
 163
 164         status = decode_string(xdr, &hdr->taglen, &hdr->tag);
 165         if (unlikely(status != 0))
 166                 return status;
 167         /* We do not like overly long tags! */
 168         if (hdr->taglen > CB_OP_TAGLEN_MAXSZ) {
 169                 printk("NFS: NFSv4 CALLBACK %s: client sent tag of length %u\n",
 170                                 __func__, hdr->taglen);
 171                 return htonl(NFS4ERR_RESOURCE);
 172         }
 173         p = read_buf(xdr, 12);
 174         if (unlikely(p == NULL))
 175                 return htonl(NFS4ERR_RESOURCE);
 176         hdr->minorversion = ntohl(*p++);
 177         /* Check for minor version support */
 178         if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
 179                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
 180         } else {
 181                 pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
 182                         "illegal minor version %u!\n",
 183                         __func__, hdr->minorversion);
 184                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 185         }
 186         hdr->nops = ntohl(*p);
 187         dprintk("%s: minorversion %d nops %d\n", __func__,
 188                 hdr->minorversion, hdr->nops);
 189         return 0;
 190 }
 191
 192 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
 193 {
 194         __be32 *p;
 195         p = read_buf(xdr, 4);
 196         if (unlikely(p == NULL))
 197                 return htonl(NFS4ERR_RESOURCE_HDR);
 198         *op = ntohl(*p);
 199         return 0;
 200 }
 201
 202 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
 203 {
 204         __be32 status;
 205
 206         status = decode_fh(xdr, &args->fh);
 207         if (unlikely(status != 0))
 208                 goto out;
 209         status = decode_bitmap(xdr, args->bitmap);
 210 out:
 211         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 212         return status;
 213 }
 214
 215 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
 216 {
 217         __be32 *p;
 218         __be32 status;
 219
 220         status = decode_delegation_stateid(xdr, &args->stateid);
 221         if (unlikely(status != 0))
 222                 goto out;
 223         p = read_buf(xdr, 4);
 224         if (unlikely(p == NULL)) {
 225                 status = htonl(NFS4ERR_RESOURCE);
 226                 goto out;
 227         }
 228         args->truncate = ntohl(*p);
 229         status = decode_fh(xdr, &args->fh);
 230 out:
 231         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 232         return status;
 233 }
 234
 235 #if defined(CONFIG_NFS_V4_1)
 236 static __be32 decode_layout_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
 237 {
 238         stateid->type = NFS4_LAYOUT_STATEID_TYPE;
 239         return decode_stateid(xdr, stateid);
 240 }
 241
 242 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 243                                        struct xdr_stream *xdr,
 244                                        struct cb_layoutrecallargs *args)
 245 {
 246         __be32 *p;
 247         __be32 status = 0;
 248         uint32_t iomode;
 249
 250         p = read_buf(xdr, 4 * sizeof(uint32_t));
 251         if (unlikely(p == NULL)) {
 252                 status = htonl(NFS4ERR_BADXDR);
 253                 goto out;
 254         }
 255
 256         args->cbl_layout_type = ntohl(*p++);
 257         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
 258          * as it is unusable and ignored with the other types.
 259          */
 260         iomode = ntohl(*p++);
 261         args->cbl_layoutchanged = ntohl(*p++);
 262         args->cbl_recall_type = ntohl(*p++);
 263
 264         if (args->cbl_recall_type == RETURN_FILE) {
 265                 args->cbl_range.iomode = iomode;
 266                 status = decode_fh(xdr, &args->cbl_fh);
 267                 if (unlikely(status != 0))
 268                         goto out;
 269
 270                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 271                 if (unlikely(p == NULL)) {
 272                         status = htonl(NFS4ERR_BADXDR);
 273                         goto out;
 274                 }
 275                 p = xdr_decode_hyper(p, &args->cbl_range.offset);
 276                 p = xdr_decode_hyper(p, &args->cbl_range.length);
 277                 status = decode_layout_stateid(xdr, &args->cbl_stateid);
 278                 if (unlikely(status != 0))
 279                         goto out;
 280         } else if (args->cbl_recall_type == RETURN_FSID) {
 281                 p = read_buf(xdr, 2 * sizeof(uint64_t));
 282                 if (unlikely(p == NULL)) {
 283                         status = htonl(NFS4ERR_BADXDR);
 284                         goto out;
 285                 }
 286                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
 287                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
 288         } else if (args->cbl_recall_type != RETURN_ALL) {
 289                 status = htonl(NFS4ERR_BADXDR);
 290                 goto out;
 291         }
 292         dprintk("%s: ltype 0x%x iomode %d changed %d recall_type %d\n",
 293                 __func__,
 294                 args->cbl_layout_type, iomode,
 295                 args->cbl_layoutchanged, args->cbl_recall_type);
 296 out:
 297         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 298         return status;
 299 }
 300
 301 static
 302 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 303                                 struct xdr_stream *xdr,
 304                                 struct cb_devicenotifyargs *args)
 305 {
 306         __be32 *p;
 307         __be32 status = 0;
 308         u32 tmp;
 309         int n, i;
 310         args->ndevs = 0;
 311
 312         /* Num of device notifications */
 313         p = read_buf(xdr, sizeof(uint32_t));
 314         if (unlikely(p == NULL)) {
 315                 status = htonl(NFS4ERR_BADXDR);
 316                 goto out;
 317         }
 318         n = ntohl(*p++);
 319         if (n <= 0)
 320                 goto out;
 321         if (n > ULONG_MAX / sizeof(*args->devs)) {
 322                 status = htonl(NFS4ERR_BADXDR);
 323                 goto out;
 324         }
 325
 326         args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
 327         if (!args->devs) {
 328                 status = htonl(NFS4ERR_DELAY);
 329                 goto out;
 330         }
 331
 332         /* Decode each dev notification */
 333         for (i = 0; i < n; i++) {
 334                 struct cb_devicenotifyitem *dev = &args->devs[i];
 335
 336                 p = read_buf(xdr, (4 * sizeof(uint32_t)) + NFS4_DEVICEID4_SIZE);
 337                 if (unlikely(p == NULL)) {
 338                         status = htonl(NFS4ERR_BADXDR);
 339                         goto err;
 340                 }
 341
 342                 tmp = ntohl(*p++);      /* bitmap size */
 343                 if (tmp != 1) {
 344                         status = htonl(NFS4ERR_INVAL);
 345                         goto err;
 346                 }
 347                 dev->cbd_notify_type = ntohl(*p++);
 348                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
 349                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
 350                         status = htonl(NFS4ERR_INVAL);
 351                         goto err;
 352                 }
 353
 354                 tmp = ntohl(*p++);      /* opaque size */
 355                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
 356                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
 357                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
 358                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
 359                         status = htonl(NFS4ERR_INVAL);
 360                         goto err;
 361                 }
 362                 dev->cbd_layout_type = ntohl(*p++);
 363                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 364                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 365
 366                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
 367                         p = read_buf(xdr, sizeof(uint32_t));
 368                         if (unlikely(p == NULL)) {
 369                                 status = htonl(NFS4ERR_BADXDR);
 370                                 goto err;
 371                         }
 372                         dev->cbd_immediate = ntohl(*p++);
 373                 } else {
 374                         dev->cbd_immediate = 0;
 375                 }
 376
 377                 args->ndevs++;
 378
 379                 dprintk("%s: type %d layout 0x%x immediate %d\n",
 380                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
 381                         dev->cbd_immediate);
 382         }
 383 out:
 384         dprintk("%s: status %d ndevs %d\n",
 385                 __func__, ntohl(status), args->ndevs);
 386         return status;
 387 err:
 388         kfree(args->devs);
 389         goto out;
 390 }
 391
 392 static __be32 decode_sessionid(struct xdr_stream *xdr,
 393                                  struct nfs4_sessionid *sid)
 394 {
 395         __be32 *p;
 396
 397         p = read_buf(xdr, NFS4_MAX_SESSIONID_LEN);
 398         if (unlikely(p == NULL))
 399                 return htonl(NFS4ERR_RESOURCE);
 400
 401         memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
 402         return 0;
 403 }
 404
 405 static __be32 decode_rc_list(struct xdr_stream *xdr,
 406                                struct referring_call_list *rc_list)
 407 {
 408         __be32 *p;
 409         int i;
 410         __be32 status;
 411
 412         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
 413         if (status)
 414                 goto out;
 415
 416         status = htonl(NFS4ERR_RESOURCE);
 417         p = read_buf(xdr, sizeof(uint32_t));
 418         if (unlikely(p == NULL))
 419                 goto out;
 420
 421         rc_list->rcl_nrefcalls = ntohl(*p++);
 422         if (rc_list->rcl_nrefcalls) {
 423                 p = read_buf(xdr,
 424                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 425                 if (unlikely(p == NULL))
 426                         goto out;
 427                 rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
 428                                                 sizeof(*rc_list->rcl_refcalls),
 429                                                 GFP_KERNEL);
 430                 if (unlikely(rc_list->rcl_refcalls == NULL))
 431                         goto out;
 432                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
 433                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
 434                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
 435                 }
 436         }
 437         status = 0;
 438
 439 out:
 440         return status;
 441 }
 442
 443 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 444                                         struct xdr_stream *xdr,
 445                                         struct cb_sequenceargs *args)
 446 {
 447         __be32 *p;
 448         int i;
 449         __be32 status;
 450
 451         status = decode_sessionid(xdr, &args->csa_sessionid);
 452         if (status)
 453                 goto out;
 454
 455         status = htonl(NFS4ERR_RESOURCE);
 456         p = read_buf(xdr, 5 * sizeof(uint32_t));
 457         if (unlikely(p == NULL))
 458                 goto out;
 459
 460         args->csa_addr = svc_addr(rqstp);
 461         args->csa_sequenceid = ntohl(*p++);
 462         args->csa_slotid = ntohl(*p++);
 463         args->csa_highestslotid = ntohl(*p++);
 464         args->csa_cachethis = ntohl(*p++);
 465         args->csa_nrclists = ntohl(*p++);
 466         args->csa_rclists = NULL;
 467         if (args->csa_nrclists) {
 468                 args->csa_rclists = kmalloc_array(args->csa_nrclists,
 469                                                   sizeof(*args->csa_rclists),
 470                                                   GFP_KERNEL);
 471                 if (unlikely(args->csa_rclists == NULL))
 472                         goto out;
 473
 474                 for (i = 0; i < args->csa_nrclists; i++) {
 475                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
 476                         if (status) {
 477                                 args->csa_nrclists = i;
 478                                 goto out_free;
 479                         }
 480                 }
 481         }
 482         status = 0;
 483
 484         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
 485                 "highestslotid %u cachethis %d nrclists %u\n",
 486                 __func__,
 487                 ((u32 *)&args->csa_sessionid)[0],
 488                 ((u32 *)&args->csa_sessionid)[1],
 489                 ((u32 *)&args->csa_sessionid)[2],
 490                 ((u32 *)&args->csa_sessionid)[3],
 491                 args->csa_sequenceid, args->csa_slotid,
 492                 args->csa_highestslotid, args->csa_cachethis,
 493                 args->csa_nrclists);
 494 out:
 495         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 496         return status;
 497
 498 out_free:
 499         for (i = 0; i < args->csa_nrclists; i++)
 500                 kfree(args->csa_rclists[i].rcl_refcalls);
 501         kfree(args->csa_rclists);
 502         goto out;
 503 }
 504
 505 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 506                                       struct xdr_stream *xdr,
 507                                       struct cb_recallanyargs *args)
 508 {
 509         uint32_t bitmap[2];
 510         __be32 *p, status;
 511
 512         p = read_buf(xdr, 4);
 513         if (unlikely(p == NULL))
 514                 return htonl(NFS4ERR_BADXDR);
 515         args->craa_objs_to_keep = ntohl(*p++);
 516         status = decode_bitmap(xdr, bitmap);
 517         if (unlikely(status))
 518                 return status;
 519         args->craa_type_mask = bitmap[0];
 520
 521         return 0;
 522 }
 523
 524 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 525                                         struct xdr_stream *xdr,
 526                                         struct cb_recallslotargs *args)
 527 {
 528         __be32 *p;
 529
 530         p = read_buf(xdr, 4);
 531         if (unlikely(p == NULL))
 532                 return htonl(NFS4ERR_BADXDR);
 533         args->crsa_target_highest_slotid = ntohl(*p++);
 534         return 0;
 535 }
 536
 537 #endif /* CONFIG_NFS_V4_1 */
 538
 539 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
 540 {
 541         __be32 *p;
 542
 543         p = xdr_reserve_space(xdr, 4 + len);
 544         if (unlikely(p == NULL))
 545                 return htonl(NFS4ERR_RESOURCE);
 546         xdr_encode_opaque(p, str, len);
 547         return 0;
 548 }
 549
 550 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
 551 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
 552 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
 553 {
 554         __be32 bm[2];
 555         __be32 *p;
 556
 557         bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
 558         bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
 559         if (bm[1] != 0) {
 560                 p = xdr_reserve_space(xdr, 16);
 561                 if (unlikely(p == NULL))
 562                         return htonl(NFS4ERR_RESOURCE);
 563                 *p++ = htonl(2);
 564                 *p++ = bm[0];
 565                 *p++ = bm[1];
 566         } else if (bm[0] != 0) {
 567                 p = xdr_reserve_space(xdr, 12);
 568                 if (unlikely(p == NULL))
 569                         return htonl(NFS4ERR_RESOURCE);
 570                 *p++ = htonl(1);
 571                 *p++ = bm[0];
 572         } else {
 573                 p = xdr_reserve_space(xdr, 8);
 574                 if (unlikely(p == NULL))
 575                         return htonl(NFS4ERR_RESOURCE);
 576                 *p++ = htonl(0);
 577         }
 578         *savep = p;
 579         return 0;
 580 }
 581
 582 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
 583 {
 584         __be32 *p;
 585
 586         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
 587                 return 0;
 588         p = xdr_reserve_space(xdr, 8);
 589         if (unlikely(!p))
 590                 return htonl(NFS4ERR_RESOURCE);
 591         p = xdr_encode_hyper(p, change);
 592         return 0;
 593 }
 594
 595 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
 596 {
 597         __be32 *p;
 598
 599         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
 600                 return 0;
 601         p = xdr_reserve_space(xdr, 8);
 602         if (unlikely(!p))
 603                 return htonl(NFS4ERR_RESOURCE);
 604         p = xdr_encode_hyper(p, size);
 605         return 0;
 606 }
 607
 608 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
 609 {
 610         __be32 *p;
 611
 612         p = xdr_reserve_space(xdr, 12);
 613         if (unlikely(!p))
 614                 return htonl(NFS4ERR_RESOURCE);
 615         p = xdr_encode_hyper(p, time->tv_sec);
 616         *p = htonl(time->tv_nsec);
 617         return 0;
 618 }
 619
 620 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 621 {
 622         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
 623                 return 0;
 624         return encode_attr_time(xdr,time);
 625 }
 626
 627 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
 628 {
 629         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
 630                 return 0;
 631         return encode_attr_time(xdr,time);
 632 }
 633
 634 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
 635 {
 636         __be32 status;
 637
 638         hdr->status = xdr_reserve_space(xdr, 4);
 639         if (unlikely(hdr->status == NULL))
 640                 return htonl(NFS4ERR_RESOURCE);
 641         status = encode_string(xdr, hdr->taglen, hdr->tag);
 642         if (unlikely(status != 0))
 643                 return status;
 644         hdr->nops = xdr_reserve_space(xdr, 4);
 645         if (unlikely(hdr->nops == NULL))
 646                 return htonl(NFS4ERR_RESOURCE);
 647         return 0;
 648 }
 649
 650 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
 651 {
 652         __be32 *p;
 653
 654         p = xdr_reserve_space(xdr, 8);
 655         if (unlikely(p == NULL))
 656                 return htonl(NFS4ERR_RESOURCE_HDR);
 657         *p++ = htonl(op);
 658         *p = res;
 659         return 0;
 660 }
 661
 662 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 663 {
 664         __be32 *savep = NULL;
 665         __be32 status = res->status;
 666
 667         if (unlikely(status != 0))
 668                 goto out;
 669         status = encode_attr_bitmap(xdr, res->bitmap, &savep);
 670         if (unlikely(status != 0))
 671                 goto out;
 672         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
 673         if (unlikely(status != 0))
 674                 goto out;
 675         status = encode_attr_size(xdr, res->bitmap, res->size);
 676         if (unlikely(status != 0))
 677                 goto out;
 678         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
 679         if (unlikely(status != 0))
 680                 goto out;
 681         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
 682         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
 683 out:
 684         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 685         return status;
 686 }
 687
 688 #if defined(CONFIG_NFS_V4_1)
 689
 690 static __be32 encode_sessionid(struct xdr_stream *xdr,
 691                                  const struct nfs4_sessionid *sid)
 692 {
 693         __be32 *p;
 694
 695         p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
 696         if (unlikely(p == NULL))
 697                 return htonl(NFS4ERR_RESOURCE);
 698
 699         memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
 700         return 0;
 701 }
 702
 703 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 704                                        struct xdr_stream *xdr,
 705                                        const struct cb_sequenceres *res)
 706 {
 707         __be32 *p;
 708         __be32 status = res->csr_status;
 709
 710         if (unlikely(status != 0))
 711                 goto out;
 712
 713         status = encode_sessionid(xdr, &res->csr_sessionid);
 714         if (status)
 715                 goto out;
 716
 717         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 718         if (unlikely(p == NULL))
 719                 return htonl(NFS4ERR_RESOURCE);
 720
 721         *p++ = htonl(res->csr_sequenceid);
 722         *p++ = htonl(res->csr_slotid);
 723         *p++ = htonl(res->csr_highestslotid);
 724         *p++ = htonl(res->csr_target_highestslotid);
 725 out:
 726         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 727         return status;
 728 }
 729
 730 static __be32
 731 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 732 {
 733         if (op_nr == OP_CB_SEQUENCE) {
 734                 if (nop != 0)
 735                         return htonl(NFS4ERR_SEQUENCE_POS);
 736         } else {
 737                 if (nop == 0)
 738                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
 739         }
 740
 741         switch (op_nr) {
 742         case OP_CB_GETATTR:
 743         case OP_CB_RECALL:
 744         case OP_CB_SEQUENCE:
 745         case OP_CB_RECALL_ANY:
 746         case OP_CB_RECALL_SLOT:
 747         case OP_CB_LAYOUTRECALL:
 748         case OP_CB_NOTIFY_DEVICEID:
 749                 *op = &callback_ops[op_nr];
 750                 break;
 751
 752         case OP_CB_NOTIFY:
 753         case OP_CB_PUSH_DELEG:
 754         case OP_CB_RECALLABLE_OBJ_AVAIL:
 755         case OP_CB_WANTS_CANCELLED:
 756         case OP_CB_NOTIFY_LOCK:
 757                 return htonl(NFS4ERR_NOTSUPP);
 758
 759         default:
 760                 return htonl(NFS4ERR_OP_ILLEGAL);
 761         }
 762
 763         return htonl(NFS_OK);
 764 }
 765
 766 static void nfs4_callback_free_slot(struct nfs4_session *session,
 767                 struct nfs4_slot *slot)
 768 {
 769         struct nfs4_slot_table *tbl = &session->bc_slot_table;
 770
 771         spin_lock(&tbl->slot_tbl_lock);
 772         /*
 773          * Let the state manager know callback processing done.
 774          * A single slot, so highest used slotid is either 0 or -1
 775          */
 776         nfs4_free_slot(tbl, slot);
 777         nfs4_slot_tbl_drain_complete(tbl);
 778         spin_unlock(&tbl->slot_tbl_lock);
 779 }
 780
 781 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 782 {
 783         if (cps->slot) {
 784                 nfs4_callback_free_slot(cps->clp->cl_session, cps->slot);
 785                 cps->slot = NULL;
 786         }
 787 }
 788
 789 #else /* CONFIG_NFS_V4_1 */
 790
 791 static __be32
 792 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 793 {
 794         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 795 }
 796
 797 static void nfs4_cb_free_slot(struct cb_process_state *cps)
 798 {
 799 }
 800 #endif /* CONFIG_NFS_V4_1 */
 801
 802 #ifdef CONFIG_NFS_V4_2
 803 static __be32
 804 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 805 {
 806         __be32 status = preprocess_nfs41_op(nop, op_nr, op);
 807         if (status != htonl(NFS4ERR_OP_ILLEGAL))
 808                 return status;
 809
 810         if (op_nr == OP_CB_OFFLOAD)
 811                 return htonl(NFS4ERR_NOTSUPP);
 812         return htonl(NFS4ERR_OP_ILLEGAL);
 813 }
 814 #else /* CONFIG_NFS_V4_2 */
 815 static __be32
 816 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
 817 {
 818         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 819 }
 820 #endif /* CONFIG_NFS_V4_2 */
 821
 822 static __be32
 823 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
 824 {
 825         switch (op_nr) {
 826         case OP_CB_GETATTR:
 827         case OP_CB_RECALL:
 828                 *op = &callback_ops[op_nr];
 829                 break;
 830         default:
 831                 return htonl(NFS4ERR_OP_ILLEGAL);
 832         }
 833
 834         return htonl(NFS_OK);
 835 }
 836
 837 static __be32 process_op(int nop, struct svc_rqst *rqstp,
 838                 struct xdr_stream *xdr_in, void *argp,
 839                 struct xdr_stream *xdr_out, void *resp,
 840                 struct cb_process_state *cps)
 841 {
 842         struct callback_op *op = &callback_ops[0];
 843         unsigned int op_nr;
 844         __be32 status;
 845         long maxlen;
 846         __be32 res;
 847
 848         dprintk("%s: start\n", __func__);
 849         status = decode_op_hdr(xdr_in, &op_nr);
 850         if (unlikely(status))
 851                 return status;
 852
 853         dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
 854                 __func__, cps->minorversion, nop, op_nr);
 855
 856         switch (cps->minorversion) {
 857         case 0:
 858                 status = preprocess_nfs4_op(op_nr, &op);
 859                 break;
 860         case 1:
 861                 status = preprocess_nfs41_op(nop, op_nr, &op);
 862                 break;
 863         case 2:
 864                 status = preprocess_nfs42_op(nop, op_nr, &op);
 865                 break;
 866         default:
 867                 status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
 868         }
 869
 870         if (status == htonl(NFS4ERR_OP_ILLEGAL))
 871                 op_nr = OP_CB_ILLEGAL;
 872         if (status)
 873                 goto encode_hdr;
 874
 875         if (cps->drc_status) {
 876                 status = cps->drc_status;
 877                 goto encode_hdr;
 878         }
 879
 880         maxlen = xdr_out->end - xdr_out->p;
 881         if (maxlen > 0 && maxlen < PAGE_SIZE) {
 882                 status = op->decode_args(rqstp, xdr_in, argp);
 883                 if (likely(status == 0))
 884                         status = op->process_op(argp, resp, cps);
 885         } else
 886                 status = htonl(NFS4ERR_RESOURCE);
 887
 888 encode_hdr:
 889         res = encode_op_hdr(xdr_out, op_nr, status);
 890         if (unlikely(res))
 891                 return res;
 892         if (op->encode_res != NULL && status == 0)
 893                 status = op->encode_res(rqstp, xdr_out, resp);
 894         dprintk("%s: done, status = %d\n", __func__, ntohl(status));
 895         return status;
 896 }
 897
 898 /*
 899  * Decode, process and encode a COMPOUND
 900  */
 901 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
 902 {
 903         struct cb_compound_hdr_arg hdr_arg = { 0 };
 904         struct cb_compound_hdr_res hdr_res = { NULL };
 905         struct xdr_stream xdr_in, xdr_out;
 906         __be32 *p, status;
 907         struct cb_process_state cps = {
 908                 .drc_status = 0,
 909                 .clp = NULL,
 910                 .net = SVC_NET(rqstp),
 911         };
 912         unsigned int nops = 0;
 913
 914         dprintk("%s: start\n", __func__);
 915
 916         xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
 917
 918         p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
 919         xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
 920
 921         status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 922         if (status == htonl(NFS4ERR_RESOURCE))
 923                 return rpc_garbage_args;
 924
 925         if (hdr_arg.minorversion == 0) {
 926                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
 927                 if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 928                         return rpc_drop_reply;
 929         }
 930
 931         cps.minorversion = hdr_arg.minorversion;
 932         hdr_res.taglen = hdr_arg.taglen;
 933         hdr_res.tag = hdr_arg.tag;
 934         if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
 935                 return rpc_system_err;
 936
 937         while (status == 0 && nops != hdr_arg.nops) {
 938                 status = process_op(nops, rqstp, &xdr_in,
 939                                     argp, &xdr_out, resp, &cps);
 940                 nops++;
 941         }
 942
 943         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
 944         * resource error in cb_compound status without returning op */
 945         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
 946                 status = htonl(NFS4ERR_RESOURCE);
 947                 nops--;
 948         }
 949
 950         *hdr_res.status = status;
 951         *hdr_res.nops = htonl(nops);
 952         nfs4_cb_free_slot(&cps);
 953         nfs_put_client(cps.clp);
 954         dprintk("%s: done, status = %u\n", __func__, ntohl(status));
 955         return rpc_success;
 956 }
 957
 958 /*
 959  * Define NFS4 callback COMPOUND ops.
 960  */
 961 static struct callback_op callback_ops[] = {
 962         [0] = {
 963                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
 964         },
 965         [OP_CB_GETATTR] = {
 966                 .process_op = (callback_process_op_t)nfs4_callback_getattr,
 967                 .decode_args = (callback_decode_arg_t)decode_getattr_args,
 968                 .encode_res = (callback_encode_res_t)encode_getattr_res,
 969                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
 970         },
 971         [OP_CB_RECALL] = {
 972                 .process_op = (callback_process_op_t)nfs4_callback_recall,
 973                 .decode_args = (callback_decode_arg_t)decode_recall_args,
 974                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
 975         },
 976 #if defined(CONFIG_NFS_V4_1)
 977         [OP_CB_LAYOUTRECALL] = {
 978                 .process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
 979                 .decode_args =
 980                         (callback_decode_arg_t)decode_layoutrecall_args,
 981                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
 982         },
 983         [OP_CB_NOTIFY_DEVICEID] = {
 984                 .process_op = (callback_process_op_t)nfs4_callback_devicenotify,
 985                 .decode_args =
 986                         (callback_decode_arg_t)decode_devicenotify_args,
 987                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
 988         },
 989         [OP_CB_SEQUENCE] = {
 990                 .process_op = (callback_process_op_t)nfs4_callback_sequence,
 991                 .decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
 992                 .encode_res = (callback_encode_res_t)encode_cb_sequence_res,
 993                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
 994         },
 995         [OP_CB_RECALL_ANY] = {
 996                 .process_op = (callback_process_op_t)nfs4_callback_recallany,
 997                 .decode_args = (callback_decode_arg_t)decode_recallany_args,
 998                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
 999         },
1000         [OP_CB_RECALL_SLOT] = {
1001                 .process_op = (callback_process_op_t)nfs4_callback_recallslot,
1002                 .decode_args = (callback_decode_arg_t)decode_recallslot_args,
1003                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
1004         },
1005 #endif /* CONFIG_NFS_V4_1 */
1006 };
1007
1008 /*
1009  * Define NFS4 callback procedures
1010  */
1011 static struct svc_procedure nfs4_callback_procedures1[] = {
1012         [CB_NULL] = {
1013                 .pc_func = nfs4_callback_null,
1014                 .pc_decode = (kxdrproc_t)nfs4_decode_void,
1015                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
1016                 .pc_xdrressize = 1,
1017         },
1018         [CB_COMPOUND] = {
1019                 .pc_func = nfs4_callback_compound,
1020                 .pc_encode = (kxdrproc_t)nfs4_encode_void,
1021                 .pc_argsize = 256,
1022                 .pc_ressize = 256,
1023                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1024         }
1025 };
1026
1027 struct svc_version nfs4_callback_version1 = {
1028         .vs_vers = 1,
1029         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1030         .vs_proc = nfs4_callback_procedures1,
1031         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1032         .vs_dispatch = NULL,
1033         .vs_hidden = 1,
1034 };
1035
1036 struct svc_version nfs4_callback_version4 = {
1037         .vs_vers = 4,
1038         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1039         .vs_proc = nfs4_callback_procedures1,
1040         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1041         .vs_dispatch = NULL,
1042         .vs_hidden = 1,
1043 };