linux/fs/nfsd/nfs4recover.c
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   1/*
   2*  Copyright (c) 2004 The Regents of the University of Michigan.
   3*  Copyright (c) 2012 Jeff Layton <jlayton@redhat.com>
   4*  All rights reserved.
   5*
   6*  Andy Adamson <andros@citi.umich.edu>
   7*
   8*  Redistribution and use in source and binary forms, with or without
   9*  modification, are permitted provided that the following conditions
  10*  are met:
  11*
  12*  1. Redistributions of source code must retain the above copyright
  13*     notice, this list of conditions and the following disclaimer.
  14*  2. Redistributions in binary form must reproduce the above copyright
  15*     notice, this list of conditions and the following disclaimer in the
  16*     documentation and/or other materials provided with the distribution.
  17*  3. Neither the name of the University nor the names of its
  18*     contributors may be used to endorse or promote products derived
  19*     from this software without specific prior written permission.
  20*
  21*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  22*  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  23*  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  24*  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25*  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  26*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  27*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  28*  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  29*  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30*  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  31*  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32*
  33*/
  34
  35#include <crypto/hash.h>
  36#include <linux/file.h>
  37#include <linux/slab.h>
  38#include <linux/namei.h>
  39#include <linux/sched.h>
  40#include <linux/fs.h>
  41#include <linux/module.h>
  42#include <net/net_namespace.h>
  43#include <linux/sunrpc/rpc_pipe_fs.h>
  44#include <linux/sunrpc/clnt.h>
  45#include <linux/nfsd/cld.h>
  46
  47#include "nfsd.h"
  48#include "state.h"
  49#include "vfs.h"
  50#include "netns.h"
  51
  52#define NFSDDBG_FACILITY                NFSDDBG_PROC
  53
  54/* Declarations */
  55struct nfsd4_client_tracking_ops {
  56        int (*init)(struct net *);
  57        void (*exit)(struct net *);
  58        void (*create)(struct nfs4_client *);
  59        void (*remove)(struct nfs4_client *);
  60        int (*check)(struct nfs4_client *);
  61        void (*grace_done)(struct nfsd_net *);
  62        uint8_t version;
  63        size_t msglen;
  64};
  65
  66static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops;
  67static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops_v2;
  68
  69/* Globals */
  70static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
  71
  72static int
  73nfs4_save_creds(const struct cred **original_creds)
  74{
  75        struct cred *new;
  76
  77        new = prepare_creds();
  78        if (!new)
  79                return -ENOMEM;
  80
  81        new->fsuid = GLOBAL_ROOT_UID;
  82        new->fsgid = GLOBAL_ROOT_GID;
  83        *original_creds = override_creds(new);
  84        put_cred(new);
  85        return 0;
  86}
  87
  88static void
  89nfs4_reset_creds(const struct cred *original)
  90{
  91        revert_creds(original);
  92}
  93
  94static void
  95md5_to_hex(char *out, char *md5)
  96{
  97        int i;
  98
  99        for (i=0; i<16; i++) {
 100                unsigned char c = md5[i];
 101
 102                *out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
 103                *out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
 104        }
 105        *out = '\0';
 106}
 107
 108static int
 109nfs4_make_rec_clidname(char *dname, const struct xdr_netobj *clname)
 110{
 111        struct xdr_netobj cksum;
 112        struct crypto_shash *tfm;
 113        int status;
 114
 115        dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
 116                        clname->len, clname->data);
 117        tfm = crypto_alloc_shash("md5", 0, 0);
 118        if (IS_ERR(tfm)) {
 119                status = PTR_ERR(tfm);
 120                goto out_no_tfm;
 121        }
 122
 123        cksum.len = crypto_shash_digestsize(tfm);
 124        cksum.data = kmalloc(cksum.len, GFP_KERNEL);
 125        if (cksum.data == NULL) {
 126                status = -ENOMEM;
 127                goto out;
 128        }
 129
 130        status = crypto_shash_tfm_digest(tfm, clname->data, clname->len,
 131                                         cksum.data);
 132        if (status)
 133                goto out;
 134
 135        md5_to_hex(dname, cksum.data);
 136
 137        status = 0;
 138out:
 139        kfree(cksum.data);
 140        crypto_free_shash(tfm);
 141out_no_tfm:
 142        return status;
 143}
 144
 145/*
 146 * If we had an error generating the recdir name for the legacy tracker
 147 * then warn the admin. If the error doesn't appear to be transient,
 148 * then disable recovery tracking.
 149 */
 150static void
 151legacy_recdir_name_error(struct nfs4_client *clp, int error)
 152{
 153        printk(KERN_ERR "NFSD: unable to generate recoverydir "
 154                        "name (%d).\n", error);
 155
 156        /*
 157         * if the algorithm just doesn't exist, then disable the recovery
 158         * tracker altogether. The crypto libs will generally return this if
 159         * FIPS is enabled as well.
 160         */
 161        if (error == -ENOENT) {
 162                printk(KERN_ERR "NFSD: disabling legacy clientid tracking. "
 163                        "Reboot recovery will not function correctly!\n");
 164                nfsd4_client_tracking_exit(clp->net);
 165        }
 166}
 167
 168static void
 169__nfsd4_create_reclaim_record_grace(struct nfs4_client *clp,
 170                const char *dname, int len, struct nfsd_net *nn)
 171{
 172        struct xdr_netobj name;
 173        struct xdr_netobj princhash = { .len = 0, .data = NULL };
 174        struct nfs4_client_reclaim *crp;
 175
 176        name.data = kmemdup(dname, len, GFP_KERNEL);
 177        if (!name.data) {
 178                dprintk("%s: failed to allocate memory for name.data!\n",
 179                        __func__);
 180                return;
 181        }
 182        name.len = len;
 183        crp = nfs4_client_to_reclaim(name, princhash, nn);
 184        if (!crp) {
 185                kfree(name.data);
 186                return;
 187        }
 188        crp->cr_clp = clp;
 189}
 190
 191static void
 192nfsd4_create_clid_dir(struct nfs4_client *clp)
 193{
 194        const struct cred *original_cred;
 195        char dname[HEXDIR_LEN];
 196        struct dentry *dir, *dentry;
 197        int status;
 198        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 199
 200        if (test_and_set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 201                return;
 202        if (!nn->rec_file)
 203                return;
 204
 205        status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 206        if (status)
 207                return legacy_recdir_name_error(clp, status);
 208
 209        status = nfs4_save_creds(&original_cred);
 210        if (status < 0)
 211                return;
 212
 213        status = mnt_want_write_file(nn->rec_file);
 214        if (status)
 215                goto out_creds;
 216
 217        dir = nn->rec_file->f_path.dentry;
 218        /* lock the parent */
 219        inode_lock(d_inode(dir));
 220
 221        dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1);
 222        if (IS_ERR(dentry)) {
 223                status = PTR_ERR(dentry);
 224                goto out_unlock;
 225        }
 226        if (d_really_is_positive(dentry))
 227                /*
 228                 * In the 4.1 case, where we're called from
 229                 * reclaim_complete(), records from the previous reboot
 230                 * may still be left, so this is OK.
 231                 *
 232                 * In the 4.0 case, we should never get here; but we may
 233                 * as well be forgiving and just succeed silently.
 234                 */
 235                goto out_put;
 236        status = vfs_mkdir(&init_user_ns, d_inode(dir), dentry, S_IRWXU);
 237out_put:
 238        dput(dentry);
 239out_unlock:
 240        inode_unlock(d_inode(dir));
 241        if (status == 0) {
 242                if (nn->in_grace)
 243                        __nfsd4_create_reclaim_record_grace(clp, dname,
 244                                        HEXDIR_LEN, nn);
 245                vfs_fsync(nn->rec_file, 0);
 246        } else {
 247                printk(KERN_ERR "NFSD: failed to write recovery record"
 248                                " (err %d); please check that %s exists"
 249                                " and is writeable", status,
 250                                user_recovery_dirname);
 251        }
 252        mnt_drop_write_file(nn->rec_file);
 253out_creds:
 254        nfs4_reset_creds(original_cred);
 255}
 256
 257typedef int (recdir_func)(struct dentry *, struct dentry *, struct nfsd_net *);
 258
 259struct name_list {
 260        char name[HEXDIR_LEN];
 261        struct list_head list;
 262};
 263
 264struct nfs4_dir_ctx {
 265        struct dir_context ctx;
 266        struct list_head names;
 267};
 268
 269static int
 270nfsd4_build_namelist(struct dir_context *__ctx, const char *name, int namlen,
 271                loff_t offset, u64 ino, unsigned int d_type)
 272{
 273        struct nfs4_dir_ctx *ctx =
 274                container_of(__ctx, struct nfs4_dir_ctx, ctx);
 275        struct name_list *entry;
 276
 277        if (namlen != HEXDIR_LEN - 1)
 278                return 0;
 279        entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
 280        if (entry == NULL)
 281                return -ENOMEM;
 282        memcpy(entry->name, name, HEXDIR_LEN - 1);
 283        entry->name[HEXDIR_LEN - 1] = '\0';
 284        list_add(&entry->list, &ctx->names);
 285        return 0;
 286}
 287
 288static int
 289nfsd4_list_rec_dir(recdir_func *f, struct nfsd_net *nn)
 290{
 291        const struct cred *original_cred;
 292        struct dentry *dir = nn->rec_file->f_path.dentry;
 293        struct nfs4_dir_ctx ctx = {
 294                .ctx.actor = nfsd4_build_namelist,
 295                .names = LIST_HEAD_INIT(ctx.names)
 296        };
 297        struct name_list *entry, *tmp;
 298        int status;
 299
 300        status = nfs4_save_creds(&original_cred);
 301        if (status < 0)
 302                return status;
 303
 304        status = vfs_llseek(nn->rec_file, 0, SEEK_SET);
 305        if (status < 0) {
 306                nfs4_reset_creds(original_cred);
 307                return status;
 308        }
 309
 310        status = iterate_dir(nn->rec_file, &ctx.ctx);
 311        inode_lock_nested(d_inode(dir), I_MUTEX_PARENT);
 312
 313        list_for_each_entry_safe(entry, tmp, &ctx.names, list) {
 314                if (!status) {
 315                        struct dentry *dentry;
 316                        dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
 317                        if (IS_ERR(dentry)) {
 318                                status = PTR_ERR(dentry);
 319                                break;
 320                        }
 321                        status = f(dir, dentry, nn);
 322                        dput(dentry);
 323                }
 324                list_del(&entry->list);
 325                kfree(entry);
 326        }
 327        inode_unlock(d_inode(dir));
 328        nfs4_reset_creds(original_cred);
 329
 330        list_for_each_entry_safe(entry, tmp, &ctx.names, list) {
 331                dprintk("NFSD: %s. Left entry %s\n", __func__, entry->name);
 332                list_del(&entry->list);
 333                kfree(entry);
 334        }
 335        return status;
 336}
 337
 338static int
 339nfsd4_unlink_clid_dir(char *name, int namlen, struct nfsd_net *nn)
 340{
 341        struct dentry *dir, *dentry;
 342        int status;
 343
 344        dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
 345
 346        dir = nn->rec_file->f_path.dentry;
 347        inode_lock_nested(d_inode(dir), I_MUTEX_PARENT);
 348        dentry = lookup_one_len(name, dir, namlen);
 349        if (IS_ERR(dentry)) {
 350                status = PTR_ERR(dentry);
 351                goto out_unlock;
 352        }
 353        status = -ENOENT;
 354        if (d_really_is_negative(dentry))
 355                goto out;
 356        status = vfs_rmdir(&init_user_ns, d_inode(dir), dentry);
 357out:
 358        dput(dentry);
 359out_unlock:
 360        inode_unlock(d_inode(dir));
 361        return status;
 362}
 363
 364static void
 365__nfsd4_remove_reclaim_record_grace(const char *dname, int len,
 366                struct nfsd_net *nn)
 367{
 368        struct xdr_netobj name;
 369        struct nfs4_client_reclaim *crp;
 370
 371        name.data = kmemdup(dname, len, GFP_KERNEL);
 372        if (!name.data) {
 373                dprintk("%s: failed to allocate memory for name.data!\n",
 374                        __func__);
 375                return;
 376        }
 377        name.len = len;
 378        crp = nfsd4_find_reclaim_client(name, nn);
 379        kfree(name.data);
 380        if (crp)
 381                nfs4_remove_reclaim_record(crp, nn);
 382}
 383
 384static void
 385nfsd4_remove_clid_dir(struct nfs4_client *clp)
 386{
 387        const struct cred *original_cred;
 388        char dname[HEXDIR_LEN];
 389        int status;
 390        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 391
 392        if (!nn->rec_file || !test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 393                return;
 394
 395        status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 396        if (status)
 397                return legacy_recdir_name_error(clp, status);
 398
 399        status = mnt_want_write_file(nn->rec_file);
 400        if (status)
 401                goto out;
 402        clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 403
 404        status = nfs4_save_creds(&original_cred);
 405        if (status < 0)
 406                goto out_drop_write;
 407
 408        status = nfsd4_unlink_clid_dir(dname, HEXDIR_LEN-1, nn);
 409        nfs4_reset_creds(original_cred);
 410        if (status == 0) {
 411                vfs_fsync(nn->rec_file, 0);
 412                if (nn->in_grace)
 413                        __nfsd4_remove_reclaim_record_grace(dname,
 414                                        HEXDIR_LEN, nn);
 415        }
 416out_drop_write:
 417        mnt_drop_write_file(nn->rec_file);
 418out:
 419        if (status)
 420                printk("NFSD: Failed to remove expired client state directory"
 421                                " %.*s\n", HEXDIR_LEN, dname);
 422}
 423
 424static int
 425purge_old(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
 426{
 427        int status;
 428        struct xdr_netobj name;
 429
 430        if (child->d_name.len != HEXDIR_LEN - 1) {
 431                printk("%s: illegal name %pd in recovery directory\n",
 432                                __func__, child);
 433                /* Keep trying; maybe the others are OK: */
 434                return 0;
 435        }
 436        name.data = kmemdup_nul(child->d_name.name, child->d_name.len, GFP_KERNEL);
 437        if (!name.data) {
 438                dprintk("%s: failed to allocate memory for name.data!\n",
 439                        __func__);
 440                goto out;
 441        }
 442        name.len = HEXDIR_LEN;
 443        if (nfs4_has_reclaimed_state(name, nn))
 444                goto out_free;
 445
 446        status = vfs_rmdir(&init_user_ns, d_inode(parent), child);
 447        if (status)
 448                printk("failed to remove client recovery directory %pd\n",
 449                                child);
 450out_free:
 451        kfree(name.data);
 452out:
 453        /* Keep trying, success or failure: */
 454        return 0;
 455}
 456
 457static void
 458nfsd4_recdir_purge_old(struct nfsd_net *nn)
 459{
 460        int status;
 461
 462        nn->in_grace = false;
 463        if (!nn->rec_file)
 464                return;
 465        status = mnt_want_write_file(nn->rec_file);
 466        if (status)
 467                goto out;
 468        status = nfsd4_list_rec_dir(purge_old, nn);
 469        if (status == 0)
 470                vfs_fsync(nn->rec_file, 0);
 471        mnt_drop_write_file(nn->rec_file);
 472out:
 473        nfs4_release_reclaim(nn);
 474        if (status)
 475                printk("nfsd4: failed to purge old clients from recovery"
 476                        " directory %pD\n", nn->rec_file);
 477}
 478
 479static int
 480load_recdir(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
 481{
 482        struct xdr_netobj name;
 483        struct xdr_netobj princhash = { .len = 0, .data = NULL };
 484
 485        if (child->d_name.len != HEXDIR_LEN - 1) {
 486                printk("%s: illegal name %pd in recovery directory\n",
 487                                __func__, child);
 488                /* Keep trying; maybe the others are OK: */
 489                return 0;
 490        }
 491        name.data = kmemdup_nul(child->d_name.name, child->d_name.len, GFP_KERNEL);
 492        if (!name.data) {
 493                dprintk("%s: failed to allocate memory for name.data!\n",
 494                        __func__);
 495                goto out;
 496        }
 497        name.len = HEXDIR_LEN;
 498        if (!nfs4_client_to_reclaim(name, princhash, nn))
 499                kfree(name.data);
 500out:
 501        return 0;
 502}
 503
 504static int
 505nfsd4_recdir_load(struct net *net) {
 506        int status;
 507        struct nfsd_net *nn =  net_generic(net, nfsd_net_id);
 508
 509        if (!nn->rec_file)
 510                return 0;
 511
 512        status = nfsd4_list_rec_dir(load_recdir, nn);
 513        if (status)
 514                printk("nfsd4: failed loading clients from recovery"
 515                        " directory %pD\n", nn->rec_file);
 516        return status;
 517}
 518
 519/*
 520 * Hold reference to the recovery directory.
 521 */
 522
 523static int
 524nfsd4_init_recdir(struct net *net)
 525{
 526        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 527        const struct cred *original_cred;
 528        int status;
 529
 530        printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
 531                        user_recovery_dirname);
 532
 533        BUG_ON(nn->rec_file);
 534
 535        status = nfs4_save_creds(&original_cred);
 536        if (status < 0) {
 537                printk("NFSD: Unable to change credentials to find recovery"
 538                       " directory: error %d\n",
 539                       status);
 540                return status;
 541        }
 542
 543        nn->rec_file = filp_open(user_recovery_dirname, O_RDONLY | O_DIRECTORY, 0);
 544        if (IS_ERR(nn->rec_file)) {
 545                printk("NFSD: unable to find recovery directory %s\n",
 546                                user_recovery_dirname);
 547                status = PTR_ERR(nn->rec_file);
 548                nn->rec_file = NULL;
 549        }
 550
 551        nfs4_reset_creds(original_cred);
 552        if (!status)
 553                nn->in_grace = true;
 554        return status;
 555}
 556
 557static void
 558nfsd4_shutdown_recdir(struct net *net)
 559{
 560        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 561
 562        if (!nn->rec_file)
 563                return;
 564        fput(nn->rec_file);
 565        nn->rec_file = NULL;
 566}
 567
 568static int
 569nfs4_legacy_state_init(struct net *net)
 570{
 571        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 572        int i;
 573
 574        nn->reclaim_str_hashtbl = kmalloc_array(CLIENT_HASH_SIZE,
 575                                                sizeof(struct list_head),
 576                                                GFP_KERNEL);
 577        if (!nn->reclaim_str_hashtbl)
 578                return -ENOMEM;
 579
 580        for (i = 0; i < CLIENT_HASH_SIZE; i++)
 581                INIT_LIST_HEAD(&nn->reclaim_str_hashtbl[i]);
 582        nn->reclaim_str_hashtbl_size = 0;
 583
 584        return 0;
 585}
 586
 587static void
 588nfs4_legacy_state_shutdown(struct net *net)
 589{
 590        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 591
 592        kfree(nn->reclaim_str_hashtbl);
 593}
 594
 595static int
 596nfsd4_load_reboot_recovery_data(struct net *net)
 597{
 598        int status;
 599
 600        status = nfsd4_init_recdir(net);
 601        if (status)
 602                return status;
 603
 604        status = nfsd4_recdir_load(net);
 605        if (status)
 606                nfsd4_shutdown_recdir(net);
 607
 608        return status;
 609}
 610
 611static int
 612nfsd4_legacy_tracking_init(struct net *net)
 613{
 614        int status;
 615
 616        /* XXX: The legacy code won't work in a container */
 617        if (net != &init_net) {
 618                pr_warn("NFSD: attempt to initialize legacy client tracking in a container ignored.\n");
 619                return -EINVAL;
 620        }
 621
 622        status = nfs4_legacy_state_init(net);
 623        if (status)
 624                return status;
 625
 626        status = nfsd4_load_reboot_recovery_data(net);
 627        if (status)
 628                goto err;
 629        pr_info("NFSD: Using legacy client tracking operations.\n");
 630        return 0;
 631
 632err:
 633        nfs4_legacy_state_shutdown(net);
 634        return status;
 635}
 636
 637static void
 638nfsd4_legacy_tracking_exit(struct net *net)
 639{
 640        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 641
 642        nfs4_release_reclaim(nn);
 643        nfsd4_shutdown_recdir(net);
 644        nfs4_legacy_state_shutdown(net);
 645}
 646
 647/*
 648 * Change the NFSv4 recovery directory to recdir.
 649 */
 650int
 651nfs4_reset_recoverydir(char *recdir)
 652{
 653        int status;
 654        struct path path;
 655
 656        status = kern_path(recdir, LOOKUP_FOLLOW, &path);
 657        if (status)
 658                return status;
 659        status = -ENOTDIR;
 660        if (d_is_dir(path.dentry)) {
 661                strcpy(user_recovery_dirname, recdir);
 662                status = 0;
 663        }
 664        path_put(&path);
 665        return status;
 666}
 667
 668char *
 669nfs4_recoverydir(void)
 670{
 671        return user_recovery_dirname;
 672}
 673
 674static int
 675nfsd4_check_legacy_client(struct nfs4_client *clp)
 676{
 677        int status;
 678        char dname[HEXDIR_LEN];
 679        struct nfs4_client_reclaim *crp;
 680        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 681        struct xdr_netobj name;
 682
 683        /* did we already find that this client is stable? */
 684        if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 685                return 0;
 686
 687        status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 688        if (status) {
 689                legacy_recdir_name_error(clp, status);
 690                return status;
 691        }
 692
 693        /* look for it in the reclaim hashtable otherwise */
 694        name.data = kmemdup(dname, HEXDIR_LEN, GFP_KERNEL);
 695        if (!name.data) {
 696                dprintk("%s: failed to allocate memory for name.data!\n",
 697                        __func__);
 698                goto out_enoent;
 699        }
 700        name.len = HEXDIR_LEN;
 701        crp = nfsd4_find_reclaim_client(name, nn);
 702        kfree(name.data);
 703        if (crp) {
 704                set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 705                crp->cr_clp = clp;
 706                return 0;
 707        }
 708
 709out_enoent:
 710        return -ENOENT;
 711}
 712
 713static const struct nfsd4_client_tracking_ops nfsd4_legacy_tracking_ops = {
 714        .init           = nfsd4_legacy_tracking_init,
 715        .exit           = nfsd4_legacy_tracking_exit,
 716        .create         = nfsd4_create_clid_dir,
 717        .remove         = nfsd4_remove_clid_dir,
 718        .check          = nfsd4_check_legacy_client,
 719        .grace_done     = nfsd4_recdir_purge_old,
 720        .version        = 1,
 721        .msglen         = 0,
 722};
 723
 724/* Globals */
 725#define NFSD_PIPE_DIR           "nfsd"
 726#define NFSD_CLD_PIPE           "cld"
 727
 728/* per-net-ns structure for holding cld upcall info */
 729struct cld_net {
 730        struct rpc_pipe         *cn_pipe;
 731        spinlock_t               cn_lock;
 732        struct list_head         cn_list;
 733        unsigned int             cn_xid;
 734        bool                     cn_has_legacy;
 735        struct crypto_shash     *cn_tfm;
 736};
 737
 738struct cld_upcall {
 739        struct list_head         cu_list;
 740        struct cld_net          *cu_net;
 741        struct completion        cu_done;
 742        union {
 743                struct cld_msg_hdr       cu_hdr;
 744                struct cld_msg           cu_msg;
 745                struct cld_msg_v2        cu_msg_v2;
 746        } cu_u;
 747};
 748
 749static int
 750__cld_pipe_upcall(struct rpc_pipe *pipe, void *cmsg, struct nfsd_net *nn)
 751{
 752        int ret;
 753        struct rpc_pipe_msg msg;
 754        struct cld_upcall *cup = container_of(cmsg, struct cld_upcall, cu_u);
 755
 756        memset(&msg, 0, sizeof(msg));
 757        msg.data = cmsg;
 758        msg.len = nn->client_tracking_ops->msglen;
 759
 760        ret = rpc_queue_upcall(pipe, &msg);
 761        if (ret < 0) {
 762                goto out;
 763        }
 764
 765        wait_for_completion(&cup->cu_done);
 766
 767        if (msg.errno < 0)
 768                ret = msg.errno;
 769out:
 770        return ret;
 771}
 772
 773static int
 774cld_pipe_upcall(struct rpc_pipe *pipe, void *cmsg, struct nfsd_net *nn)
 775{
 776        int ret;
 777
 778        /*
 779         * -EAGAIN occurs when pipe is closed and reopened while there are
 780         *  upcalls queued.
 781         */
 782        do {
 783                ret = __cld_pipe_upcall(pipe, cmsg, nn);
 784        } while (ret == -EAGAIN);
 785
 786        return ret;
 787}
 788
 789static ssize_t
 790__cld_pipe_inprogress_downcall(const struct cld_msg_v2 __user *cmsg,
 791                struct nfsd_net *nn)
 792{
 793        uint8_t cmd, princhashlen;
 794        struct xdr_netobj name, princhash = { .len = 0, .data = NULL };
 795        uint16_t namelen;
 796        struct cld_net *cn = nn->cld_net;
 797
 798        if (get_user(cmd, &cmsg->cm_cmd)) {
 799                dprintk("%s: error when copying cmd from userspace", __func__);
 800                return -EFAULT;
 801        }
 802        if (cmd == Cld_GraceStart) {
 803                if (nn->client_tracking_ops->version >= 2) {
 804                        const struct cld_clntinfo __user *ci;
 805
 806                        ci = &cmsg->cm_u.cm_clntinfo;
 807                        if (get_user(namelen, &ci->cc_name.cn_len))
 808                                return -EFAULT;
 809                        name.data = memdup_user(&ci->cc_name.cn_id, namelen);
 810                        if (IS_ERR_OR_NULL(name.data))
 811                                return -EFAULT;
 812                        name.len = namelen;
 813                        get_user(princhashlen, &ci->cc_princhash.cp_len);
 814                        if (princhashlen > 0) {
 815                                princhash.data = memdup_user(
 816                                                &ci->cc_princhash.cp_data,
 817                                                princhashlen);
 818                                if (IS_ERR_OR_NULL(princhash.data))
 819                                        return -EFAULT;
 820                                princhash.len = princhashlen;
 821                        } else
 822                                princhash.len = 0;
 823                } else {
 824                        const struct cld_name __user *cnm;
 825
 826                        cnm = &cmsg->cm_u.cm_name;
 827                        if (get_user(namelen, &cnm->cn_len))
 828                                return -EFAULT;
 829                        name.data = memdup_user(&cnm->cn_id, namelen);
 830                        if (IS_ERR_OR_NULL(name.data))
 831                                return -EFAULT;
 832                        name.len = namelen;
 833                }
 834                if (name.len > 5 && memcmp(name.data, "hash:", 5) == 0) {
 835                        name.len = name.len - 5;
 836                        memmove(name.data, name.data + 5, name.len);
 837                        cn->cn_has_legacy = true;
 838                }
 839                if (!nfs4_client_to_reclaim(name, princhash, nn)) {
 840                        kfree(name.data);
 841                        kfree(princhash.data);
 842                        return -EFAULT;
 843                }
 844                return nn->client_tracking_ops->msglen;
 845        }
 846        return -EFAULT;
 847}
 848
 849static ssize_t
 850cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 851{
 852        struct cld_upcall *tmp, *cup;
 853        struct cld_msg_hdr __user *hdr = (struct cld_msg_hdr __user *)src;
 854        struct cld_msg_v2 __user *cmsg = (struct cld_msg_v2 __user *)src;
 855        uint32_t xid;
 856        struct nfsd_net *nn = net_generic(file_inode(filp)->i_sb->s_fs_info,
 857                                                nfsd_net_id);
 858        struct cld_net *cn = nn->cld_net;
 859        int16_t status;
 860
 861        if (mlen != nn->client_tracking_ops->msglen) {
 862                dprintk("%s: got %zu bytes, expected %zu\n", __func__, mlen,
 863                        nn->client_tracking_ops->msglen);
 864                return -EINVAL;
 865        }
 866
 867        /* copy just the xid so we can try to find that */
 868        if (copy_from_user(&xid, &hdr->cm_xid, sizeof(xid)) != 0) {
 869                dprintk("%s: error when copying xid from userspace", __func__);
 870                return -EFAULT;
 871        }
 872
 873        /*
 874         * copy the status so we know whether to remove the upcall from the
 875         * list (for -EINPROGRESS, we just want to make sure the xid is
 876         * valid, not remove the upcall from the list)
 877         */
 878        if (get_user(status, &hdr->cm_status)) {
 879                dprintk("%s: error when copying status from userspace", __func__);
 880                return -EFAULT;
 881        }
 882
 883        /* walk the list and find corresponding xid */
 884        cup = NULL;
 885        spin_lock(&cn->cn_lock);
 886        list_for_each_entry(tmp, &cn->cn_list, cu_list) {
 887                if (get_unaligned(&tmp->cu_u.cu_hdr.cm_xid) == xid) {
 888                        cup = tmp;
 889                        if (status != -EINPROGRESS)
 890                                list_del_init(&cup->cu_list);
 891                        break;
 892                }
 893        }
 894        spin_unlock(&cn->cn_lock);
 895
 896        /* couldn't find upcall? */
 897        if (!cup) {
 898                dprintk("%s: couldn't find upcall -- xid=%u\n", __func__, xid);
 899                return -EINVAL;
 900        }
 901
 902        if (status == -EINPROGRESS)
 903                return __cld_pipe_inprogress_downcall(cmsg, nn);
 904
 905        if (copy_from_user(&cup->cu_u.cu_msg_v2, src, mlen) != 0)
 906                return -EFAULT;
 907
 908        complete(&cup->cu_done);
 909        return mlen;
 910}
 911
 912static void
 913cld_pipe_destroy_msg(struct rpc_pipe_msg *msg)
 914{
 915        struct cld_msg *cmsg = msg->data;
 916        struct cld_upcall *cup = container_of(cmsg, struct cld_upcall,
 917                                                 cu_u.cu_msg);
 918
 919        /* errno >= 0 means we got a downcall */
 920        if (msg->errno >= 0)
 921                return;
 922
 923        complete(&cup->cu_done);
 924}
 925
 926static const struct rpc_pipe_ops cld_upcall_ops = {
 927        .upcall         = rpc_pipe_generic_upcall,
 928        .downcall       = cld_pipe_downcall,
 929        .destroy_msg    = cld_pipe_destroy_msg,
 930};
 931
 932static struct dentry *
 933nfsd4_cld_register_sb(struct super_block *sb, struct rpc_pipe *pipe)
 934{
 935        struct dentry *dir, *dentry;
 936
 937        dir = rpc_d_lookup_sb(sb, NFSD_PIPE_DIR);
 938        if (dir == NULL)
 939                return ERR_PTR(-ENOENT);
 940        dentry = rpc_mkpipe_dentry(dir, NFSD_CLD_PIPE, NULL, pipe);
 941        dput(dir);
 942        return dentry;
 943}
 944
 945static void
 946nfsd4_cld_unregister_sb(struct rpc_pipe *pipe)
 947{
 948        if (pipe->dentry)
 949                rpc_unlink(pipe->dentry);
 950}
 951
 952static struct dentry *
 953nfsd4_cld_register_net(struct net *net, struct rpc_pipe *pipe)
 954{
 955        struct super_block *sb;
 956        struct dentry *dentry;
 957
 958        sb = rpc_get_sb_net(net);
 959        if (!sb)
 960                return NULL;
 961        dentry = nfsd4_cld_register_sb(sb, pipe);
 962        rpc_put_sb_net(net);
 963        return dentry;
 964}
 965
 966static void
 967nfsd4_cld_unregister_net(struct net *net, struct rpc_pipe *pipe)
 968{
 969        struct super_block *sb;
 970
 971        sb = rpc_get_sb_net(net);
 972        if (sb) {
 973                nfsd4_cld_unregister_sb(pipe);
 974                rpc_put_sb_net(net);
 975        }
 976}
 977
 978/* Initialize rpc_pipefs pipe for communication with client tracking daemon */
 979static int
 980__nfsd4_init_cld_pipe(struct net *net)
 981{
 982        int ret;
 983        struct dentry *dentry;
 984        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 985        struct cld_net *cn;
 986
 987        if (nn->cld_net)
 988                return 0;
 989
 990        cn = kzalloc(sizeof(*cn), GFP_KERNEL);
 991        if (!cn) {
 992                ret = -ENOMEM;
 993                goto err;
 994        }
 995
 996        cn->cn_pipe = rpc_mkpipe_data(&cld_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
 997        if (IS_ERR(cn->cn_pipe)) {
 998                ret = PTR_ERR(cn->cn_pipe);
 999                goto err;
1000        }
1001        spin_lock_init(&cn->cn_lock);
1002        INIT_LIST_HEAD(&cn->cn_list);
1003
1004        dentry = nfsd4_cld_register_net(net, cn->cn_pipe);
1005        if (IS_ERR(dentry)) {
1006                ret = PTR_ERR(dentry);
1007                goto err_destroy_data;
1008        }
1009
1010        cn->cn_pipe->dentry = dentry;
1011        cn->cn_has_legacy = false;
1012        nn->cld_net = cn;
1013        return 0;
1014
1015err_destroy_data:
1016        rpc_destroy_pipe_data(cn->cn_pipe);
1017err:
1018        kfree(cn);
1019        printk(KERN_ERR "NFSD: unable to create nfsdcld upcall pipe (%d)\n",
1020                        ret);
1021        return ret;
1022}
1023
1024static int
1025nfsd4_init_cld_pipe(struct net *net)
1026{
1027        int status;
1028
1029        status = __nfsd4_init_cld_pipe(net);
1030        if (!status)
1031                pr_info("NFSD: Using old nfsdcld client tracking operations.\n");
1032        return status;
1033}
1034
1035static void
1036nfsd4_remove_cld_pipe(struct net *net)
1037{
1038        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1039        struct cld_net *cn = nn->cld_net;
1040
1041        nfsd4_cld_unregister_net(net, cn->cn_pipe);
1042        rpc_destroy_pipe_data(cn->cn_pipe);
1043        if (cn->cn_tfm)
1044                crypto_free_shash(cn->cn_tfm);
1045        kfree(nn->cld_net);
1046        nn->cld_net = NULL;
1047}
1048
1049static struct cld_upcall *
1050alloc_cld_upcall(struct nfsd_net *nn)
1051{
1052        struct cld_upcall *new, *tmp;
1053        struct cld_net *cn = nn->cld_net;
1054
1055        new = kzalloc(sizeof(*new), GFP_KERNEL);
1056        if (!new)
1057                return new;
1058
1059        /* FIXME: hard cap on number in flight? */
1060restart_search:
1061        spin_lock(&cn->cn_lock);
1062        list_for_each_entry(tmp, &cn->cn_list, cu_list) {
1063                if (tmp->cu_u.cu_msg.cm_xid == cn->cn_xid) {
1064                        cn->cn_xid++;
1065                        spin_unlock(&cn->cn_lock);
1066                        goto restart_search;
1067                }
1068        }
1069        init_completion(&new->cu_done);
1070        new->cu_u.cu_msg.cm_vers = nn->client_tracking_ops->version;
1071        put_unaligned(cn->cn_xid++, &new->cu_u.cu_msg.cm_xid);
1072        new->cu_net = cn;
1073        list_add(&new->cu_list, &cn->cn_list);
1074        spin_unlock(&cn->cn_lock);
1075
1076        dprintk("%s: allocated xid %u\n", __func__, new->cu_u.cu_msg.cm_xid);
1077
1078        return new;
1079}
1080
1081static void
1082free_cld_upcall(struct cld_upcall *victim)
1083{
1084        struct cld_net *cn = victim->cu_net;
1085
1086        spin_lock(&cn->cn_lock);
1087        list_del(&victim->cu_list);
1088        spin_unlock(&cn->cn_lock);
1089        kfree(victim);
1090}
1091
1092/* Ask daemon to create a new record */
1093static void
1094nfsd4_cld_create(struct nfs4_client *clp)
1095{
1096        int ret;
1097        struct cld_upcall *cup;
1098        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1099        struct cld_net *cn = nn->cld_net;
1100
1101        /* Don't upcall if it's already stored */
1102        if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1103                return;
1104
1105        cup = alloc_cld_upcall(nn);
1106        if (!cup) {
1107                ret = -ENOMEM;
1108                goto out_err;
1109        }
1110
1111        cup->cu_u.cu_msg.cm_cmd = Cld_Create;
1112        cup->cu_u.cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
1113        memcpy(cup->cu_u.cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
1114                        clp->cl_name.len);
1115
1116        ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1117        if (!ret) {
1118                ret = cup->cu_u.cu_msg.cm_status;
1119                set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1120        }
1121
1122        free_cld_upcall(cup);
1123out_err:
1124        if (ret)
1125                printk(KERN_ERR "NFSD: Unable to create client "
1126                                "record on stable storage: %d\n", ret);
1127}
1128
1129/* Ask daemon to create a new record */
1130static void
1131nfsd4_cld_create_v2(struct nfs4_client *clp)
1132{
1133        int ret;
1134        struct cld_upcall *cup;
1135        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1136        struct cld_net *cn = nn->cld_net;
1137        struct cld_msg_v2 *cmsg;
1138        struct crypto_shash *tfm = cn->cn_tfm;
1139        struct xdr_netobj cksum;
1140        char *principal = NULL;
1141
1142        /* Don't upcall if it's already stored */
1143        if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1144                return;
1145
1146        cup = alloc_cld_upcall(nn);
1147        if (!cup) {
1148                ret = -ENOMEM;
1149                goto out_err;
1150        }
1151
1152        cmsg = &cup->cu_u.cu_msg_v2;
1153        cmsg->cm_cmd = Cld_Create;
1154        cmsg->cm_u.cm_clntinfo.cc_name.cn_len = clp->cl_name.len;
1155        memcpy(cmsg->cm_u.cm_clntinfo.cc_name.cn_id, clp->cl_name.data,
1156                        clp->cl_name.len);
1157        if (clp->cl_cred.cr_raw_principal)
1158                principal = clp->cl_cred.cr_raw_principal;
1159        else if (clp->cl_cred.cr_principal)
1160                principal = clp->cl_cred.cr_principal;
1161        if (principal) {
1162                cksum.len = crypto_shash_digestsize(tfm);
1163                cksum.data = kmalloc(cksum.len, GFP_KERNEL);
1164                if (cksum.data == NULL) {
1165                        ret = -ENOMEM;
1166                        goto out;
1167                }
1168                ret = crypto_shash_tfm_digest(tfm, principal, strlen(principal),
1169                                              cksum.data);
1170                if (ret) {
1171                        kfree(cksum.data);
1172                        goto out;
1173                }
1174                cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = cksum.len;
1175                memcpy(cmsg->cm_u.cm_clntinfo.cc_princhash.cp_data,
1176                       cksum.data, cksum.len);
1177                kfree(cksum.data);
1178        } else
1179                cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = 0;
1180
1181        ret = cld_pipe_upcall(cn->cn_pipe, cmsg, nn);
1182        if (!ret) {
1183                ret = cmsg->cm_status;
1184                set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1185        }
1186
1187out:
1188        free_cld_upcall(cup);
1189out_err:
1190        if (ret)
1191                pr_err("NFSD: Unable to create client record on stable storage: %d\n",
1192                                ret);
1193}
1194
1195/* Ask daemon to create a new record */
1196static void
1197nfsd4_cld_remove(struct nfs4_client *clp)
1198{
1199        int ret;
1200        struct cld_upcall *cup;
1201        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1202        struct cld_net *cn = nn->cld_net;
1203
1204        /* Don't upcall if it's already removed */
1205        if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1206                return;
1207
1208        cup = alloc_cld_upcall(nn);
1209        if (!cup) {
1210                ret = -ENOMEM;
1211                goto out_err;
1212        }
1213
1214        cup->cu_u.cu_msg.cm_cmd = Cld_Remove;
1215        cup->cu_u.cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
1216        memcpy(cup->cu_u.cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
1217                        clp->cl_name.len);
1218
1219        ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1220        if (!ret) {
1221                ret = cup->cu_u.cu_msg.cm_status;
1222                clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1223        }
1224
1225        free_cld_upcall(cup);
1226out_err:
1227        if (ret)
1228                printk(KERN_ERR "NFSD: Unable to remove client "
1229                                "record from stable storage: %d\n", ret);
1230}
1231
1232/*
1233 * For older nfsdcld's that do not allow us to "slurp" the clients
1234 * from the tracking database during startup.
1235 *
1236 * Check for presence of a record, and update its timestamp
1237 */
1238static int
1239nfsd4_cld_check_v0(struct nfs4_client *clp)
1240{
1241        int ret;
1242        struct cld_upcall *cup;
1243        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1244        struct cld_net *cn = nn->cld_net;
1245
1246        /* Don't upcall if one was already stored during this grace pd */
1247        if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1248                return 0;
1249
1250        cup = alloc_cld_upcall(nn);
1251        if (!cup) {
1252                printk(KERN_ERR "NFSD: Unable to check client record on "
1253                                "stable storage: %d\n", -ENOMEM);
1254                return -ENOMEM;
1255        }
1256
1257        cup->cu_u.cu_msg.cm_cmd = Cld_Check;
1258        cup->cu_u.cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
1259        memcpy(cup->cu_u.cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
1260                        clp->cl_name.len);
1261
1262        ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1263        if (!ret) {
1264                ret = cup->cu_u.cu_msg.cm_status;
1265                set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1266        }
1267
1268        free_cld_upcall(cup);
1269        return ret;
1270}
1271
1272/*
1273 * For newer nfsdcld's that allow us to "slurp" the clients
1274 * from the tracking database during startup.
1275 *
1276 * Check for presence of a record in the reclaim_str_hashtbl
1277 */
1278static int
1279nfsd4_cld_check(struct nfs4_client *clp)
1280{
1281        struct nfs4_client_reclaim *crp;
1282        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1283        struct cld_net *cn = nn->cld_net;
1284        int status;
1285        char dname[HEXDIR_LEN];
1286        struct xdr_netobj name;
1287
1288        /* did we already find that this client is stable? */
1289        if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1290                return 0;
1291
1292        /* look for it in the reclaim hashtable otherwise */
1293        crp = nfsd4_find_reclaim_client(clp->cl_name, nn);
1294        if (crp)
1295                goto found;
1296
1297        if (cn->cn_has_legacy) {
1298                status = nfs4_make_rec_clidname(dname, &clp->cl_name);
1299                if (status)
1300                        return -ENOENT;
1301
1302                name.data = kmemdup(dname, HEXDIR_LEN, GFP_KERNEL);
1303                if (!name.data) {
1304                        dprintk("%s: failed to allocate memory for name.data!\n",
1305                                __func__);
1306                        return -ENOENT;
1307                }
1308                name.len = HEXDIR_LEN;
1309                crp = nfsd4_find_reclaim_client(name, nn);
1310                kfree(name.data);
1311                if (crp)
1312                        goto found;
1313
1314        }
1315        return -ENOENT;
1316found:
1317        crp->cr_clp = clp;
1318        return 0;
1319}
1320
1321static int
1322nfsd4_cld_check_v2(struct nfs4_client *clp)
1323{
1324        struct nfs4_client_reclaim *crp;
1325        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1326        struct cld_net *cn = nn->cld_net;
1327        int status;
1328        char dname[HEXDIR_LEN];
1329        struct xdr_netobj name;
1330        struct crypto_shash *tfm = cn->cn_tfm;
1331        struct xdr_netobj cksum;
1332        char *principal = NULL;
1333
1334        /* did we already find that this client is stable? */
1335        if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1336                return 0;
1337
1338        /* look for it in the reclaim hashtable otherwise */
1339        crp = nfsd4_find_reclaim_client(clp->cl_name, nn);
1340        if (crp)
1341                goto found;
1342
1343        if (cn->cn_has_legacy) {
1344                status = nfs4_make_rec_clidname(dname, &clp->cl_name);
1345                if (status)
1346                        return -ENOENT;
1347
1348                name.data = kmemdup(dname, HEXDIR_LEN, GFP_KERNEL);
1349                if (!name.data) {
1350                        dprintk("%s: failed to allocate memory for name.data\n",
1351                                        __func__);
1352                        return -ENOENT;
1353                }
1354                name.len = HEXDIR_LEN;
1355                crp = nfsd4_find_reclaim_client(name, nn);
1356                kfree(name.data);
1357                if (crp)
1358                        goto found;
1359
1360        }
1361        return -ENOENT;
1362found:
1363        if (crp->cr_princhash.len) {
1364                if (clp->cl_cred.cr_raw_principal)
1365                        principal = clp->cl_cred.cr_raw_principal;
1366                else if (clp->cl_cred.cr_principal)
1367                        principal = clp->cl_cred.cr_principal;
1368                if (principal == NULL)
1369                        return -ENOENT;
1370                cksum.len = crypto_shash_digestsize(tfm);
1371                cksum.data = kmalloc(cksum.len, GFP_KERNEL);
1372                if (cksum.data == NULL)
1373                        return -ENOENT;
1374                status = crypto_shash_tfm_digest(tfm, principal,
1375                                                 strlen(principal), cksum.data);
1376                if (status) {
1377                        kfree(cksum.data);
1378                        return -ENOENT;
1379                }
1380                if (memcmp(crp->cr_princhash.data, cksum.data,
1381                                crp->cr_princhash.len)) {
1382                        kfree(cksum.data);
1383                        return -ENOENT;
1384                }
1385                kfree(cksum.data);
1386        }
1387        crp->cr_clp = clp;
1388        return 0;
1389}
1390
1391static int
1392nfsd4_cld_grace_start(struct nfsd_net *nn)
1393{
1394        int ret;
1395        struct cld_upcall *cup;
1396        struct cld_net *cn = nn->cld_net;
1397
1398        cup = alloc_cld_upcall(nn);
1399        if (!cup) {
1400                ret = -ENOMEM;
1401                goto out_err;
1402        }
1403
1404        cup->cu_u.cu_msg.cm_cmd = Cld_GraceStart;
1405        ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1406        if (!ret)
1407                ret = cup->cu_u.cu_msg.cm_status;
1408
1409        free_cld_upcall(cup);
1410out_err:
1411        if (ret)
1412                dprintk("%s: Unable to get clients from userspace: %d\n",
1413                        __func__, ret);
1414        return ret;
1415}
1416
1417/* For older nfsdcld's that need cm_gracetime */
1418static void
1419nfsd4_cld_grace_done_v0(struct nfsd_net *nn)
1420{
1421        int ret;
1422        struct cld_upcall *cup;
1423        struct cld_net *cn = nn->cld_net;
1424
1425        cup = alloc_cld_upcall(nn);
1426        if (!cup) {
1427                ret = -ENOMEM;
1428                goto out_err;
1429        }
1430
1431        cup->cu_u.cu_msg.cm_cmd = Cld_GraceDone;
1432        cup->cu_u.cu_msg.cm_u.cm_gracetime = nn->boot_time;
1433        ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1434        if (!ret)
1435                ret = cup->cu_u.cu_msg.cm_status;
1436
1437        free_cld_upcall(cup);
1438out_err:
1439        if (ret)
1440                printk(KERN_ERR "NFSD: Unable to end grace period: %d\n", ret);
1441}
1442
1443/*
1444 * For newer nfsdcld's that do not need cm_gracetime.  We also need to call
1445 * nfs4_release_reclaim() to clear out the reclaim_str_hashtbl.
1446 */
1447static void
1448nfsd4_cld_grace_done(struct nfsd_net *nn)
1449{
1450        int ret;
1451        struct cld_upcall *cup;
1452        struct cld_net *cn = nn->cld_net;
1453
1454        cup = alloc_cld_upcall(nn);
1455        if (!cup) {
1456                ret = -ENOMEM;
1457                goto out_err;
1458        }
1459
1460        cup->cu_u.cu_msg.cm_cmd = Cld_GraceDone;
1461        ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1462        if (!ret)
1463                ret = cup->cu_u.cu_msg.cm_status;
1464
1465        free_cld_upcall(cup);
1466out_err:
1467        nfs4_release_reclaim(nn);
1468        if (ret)
1469                printk(KERN_ERR "NFSD: Unable to end grace period: %d\n", ret);
1470}
1471
1472static int
1473nfs4_cld_state_init(struct net *net)
1474{
1475        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1476        int i;
1477
1478        nn->reclaim_str_hashtbl = kmalloc_array(CLIENT_HASH_SIZE,
1479                                                sizeof(struct list_head),
1480                                                GFP_KERNEL);
1481        if (!nn->reclaim_str_hashtbl)
1482                return -ENOMEM;
1483
1484        for (i = 0; i < CLIENT_HASH_SIZE; i++)
1485                INIT_LIST_HEAD(&nn->reclaim_str_hashtbl[i]);
1486        nn->reclaim_str_hashtbl_size = 0;
1487        nn->track_reclaim_completes = true;
1488        atomic_set(&nn->nr_reclaim_complete, 0);
1489
1490        return 0;
1491}
1492
1493static void
1494nfs4_cld_state_shutdown(struct net *net)
1495{
1496        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1497
1498        nn->track_reclaim_completes = false;
1499        kfree(nn->reclaim_str_hashtbl);
1500}
1501
1502static bool
1503cld_running(struct nfsd_net *nn)
1504{
1505        struct cld_net *cn = nn->cld_net;
1506        struct rpc_pipe *pipe = cn->cn_pipe;
1507
1508        return pipe->nreaders || pipe->nwriters;
1509}
1510
1511static int
1512nfsd4_cld_get_version(struct nfsd_net *nn)
1513{
1514        int ret = 0;
1515        struct cld_upcall *cup;
1516        struct cld_net *cn = nn->cld_net;
1517        uint8_t version;
1518
1519        cup = alloc_cld_upcall(nn);
1520        if (!cup) {
1521                ret = -ENOMEM;
1522                goto out_err;
1523        }
1524        cup->cu_u.cu_msg.cm_cmd = Cld_GetVersion;
1525        ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1526        if (!ret) {
1527                ret = cup->cu_u.cu_msg.cm_status;
1528                if (ret)
1529                        goto out_free;
1530                version = cup->cu_u.cu_msg.cm_u.cm_version;
1531                dprintk("%s: userspace returned version %u\n",
1532                                __func__, version);
1533                if (version < 1)
1534                        version = 1;
1535                else if (version > CLD_UPCALL_VERSION)
1536                        version = CLD_UPCALL_VERSION;
1537
1538                switch (version) {
1539                case 1:
1540                        nn->client_tracking_ops = &nfsd4_cld_tracking_ops;
1541                        break;
1542                case 2:
1543                        nn->client_tracking_ops = &nfsd4_cld_tracking_ops_v2;
1544                        break;
1545                default:
1546                        break;
1547                }
1548        }
1549out_free:
1550        free_cld_upcall(cup);
1551out_err:
1552        if (ret)
1553                dprintk("%s: Unable to get version from userspace: %d\n",
1554                        __func__, ret);
1555        return ret;
1556}
1557
1558static int
1559nfsd4_cld_tracking_init(struct net *net)
1560{
1561        int status;
1562        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1563        bool running;
1564        int retries = 10;
1565        struct crypto_shash *tfm;
1566
1567        status = nfs4_cld_state_init(net);
1568        if (status)
1569                return status;
1570
1571        status = __nfsd4_init_cld_pipe(net);
1572        if (status)
1573                goto err_shutdown;
1574
1575        /*
1576         * rpc pipe upcalls take 30 seconds to time out, so we don't want to
1577         * queue an upcall unless we know that nfsdcld is running (because we
1578         * want this to fail fast so that nfsd4_client_tracking_init() can try
1579         * the next client tracking method).  nfsdcld should already be running
1580         * before nfsd is started, so the wait here is for nfsdcld to open the
1581         * pipefs file we just created.
1582         */
1583        while (!(running = cld_running(nn)) && retries--)
1584                msleep(100);
1585
1586        if (!running) {
1587                status = -ETIMEDOUT;
1588                goto err_remove;
1589        }
1590        tfm = crypto_alloc_shash("sha256", 0, 0);
1591        if (IS_ERR(tfm)) {
1592                status = PTR_ERR(tfm);
1593                goto err_remove;
1594        }
1595        nn->cld_net->cn_tfm = tfm;
1596
1597        status = nfsd4_cld_get_version(nn);
1598        if (status == -EOPNOTSUPP)
1599                pr_warn("NFSD: nfsdcld GetVersion upcall failed. Please upgrade nfsdcld.\n");
1600
1601        status = nfsd4_cld_grace_start(nn);
1602        if (status) {
1603                if (status == -EOPNOTSUPP)
1604                        pr_warn("NFSD: nfsdcld GraceStart upcall failed. Please upgrade nfsdcld.\n");
1605                nfs4_release_reclaim(nn);
1606                goto err_remove;
1607        } else
1608                pr_info("NFSD: Using nfsdcld client tracking operations.\n");
1609        return 0;
1610
1611err_remove:
1612        nfsd4_remove_cld_pipe(net);
1613err_shutdown:
1614        nfs4_cld_state_shutdown(net);
1615        return status;
1616}
1617
1618static void
1619nfsd4_cld_tracking_exit(struct net *net)
1620{
1621        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1622
1623        nfs4_release_reclaim(nn);
1624        nfsd4_remove_cld_pipe(net);
1625        nfs4_cld_state_shutdown(net);
1626}
1627
1628/* For older nfsdcld's */
1629static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops_v0 = {
1630        .init           = nfsd4_init_cld_pipe,
1631        .exit           = nfsd4_remove_cld_pipe,
1632        .create         = nfsd4_cld_create,
1633        .remove         = nfsd4_cld_remove,
1634        .check          = nfsd4_cld_check_v0,
1635        .grace_done     = nfsd4_cld_grace_done_v0,
1636        .version        = 1,
1637        .msglen         = sizeof(struct cld_msg),
1638};
1639
1640/* For newer nfsdcld's */
1641static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops = {
1642        .init           = nfsd4_cld_tracking_init,
1643        .exit           = nfsd4_cld_tracking_exit,
1644        .create         = nfsd4_cld_create,
1645        .remove         = nfsd4_cld_remove,
1646        .check          = nfsd4_cld_check,
1647        .grace_done     = nfsd4_cld_grace_done,
1648        .version        = 1,
1649        .msglen         = sizeof(struct cld_msg),
1650};
1651
1652/* v2 create/check ops include the principal, if available */
1653static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops_v2 = {
1654        .init           = nfsd4_cld_tracking_init,
1655        .exit           = nfsd4_cld_tracking_exit,
1656        .create         = nfsd4_cld_create_v2,
1657        .remove         = nfsd4_cld_remove,
1658        .check          = nfsd4_cld_check_v2,
1659        .grace_done     = nfsd4_cld_grace_done,
1660        .version        = 2,
1661        .msglen         = sizeof(struct cld_msg_v2),
1662};
1663
1664/* upcall via usermodehelper */
1665static char cltrack_prog[PATH_MAX] = "/sbin/nfsdcltrack";
1666module_param_string(cltrack_prog, cltrack_prog, sizeof(cltrack_prog),
1667                        S_IRUGO|S_IWUSR);
1668MODULE_PARM_DESC(cltrack_prog, "Path to the nfsdcltrack upcall program");
1669
1670static bool cltrack_legacy_disable;
1671module_param(cltrack_legacy_disable, bool, S_IRUGO|S_IWUSR);
1672MODULE_PARM_DESC(cltrack_legacy_disable,
1673                "Disable legacy recoverydir conversion. Default: false");
1674
1675#define LEGACY_TOPDIR_ENV_PREFIX "NFSDCLTRACK_LEGACY_TOPDIR="
1676#define LEGACY_RECDIR_ENV_PREFIX "NFSDCLTRACK_LEGACY_RECDIR="
1677#define HAS_SESSION_ENV_PREFIX "NFSDCLTRACK_CLIENT_HAS_SESSION="
1678#define GRACE_START_ENV_PREFIX "NFSDCLTRACK_GRACE_START="
1679
1680static char *
1681nfsd4_cltrack_legacy_topdir(void)
1682{
1683        int copied;
1684        size_t len;
1685        char *result;
1686
1687        if (cltrack_legacy_disable)
1688                return NULL;
1689
1690        len = strlen(LEGACY_TOPDIR_ENV_PREFIX) +
1691                strlen(nfs4_recoverydir()) + 1;
1692
1693        result = kmalloc(len, GFP_KERNEL);
1694        if (!result)
1695                return result;
1696
1697        copied = snprintf(result, len, LEGACY_TOPDIR_ENV_PREFIX "%s",
1698                                nfs4_recoverydir());
1699        if (copied >= len) {
1700                /* just return nothing if output was truncated */
1701                kfree(result);
1702                return NULL;
1703        }
1704
1705        return result;
1706}
1707
1708static char *
1709nfsd4_cltrack_legacy_recdir(const struct xdr_netobj *name)
1710{
1711        int copied;
1712        size_t len;
1713        char *result;
1714
1715        if (cltrack_legacy_disable)
1716                return NULL;
1717
1718        /* +1 is for '/' between "topdir" and "recdir" */
1719        len = strlen(LEGACY_RECDIR_ENV_PREFIX) +
1720                strlen(nfs4_recoverydir()) + 1 + HEXDIR_LEN;
1721
1722        result = kmalloc(len, GFP_KERNEL);
1723        if (!result)
1724                return result;
1725
1726        copied = snprintf(result, len, LEGACY_RECDIR_ENV_PREFIX "%s/",
1727                                nfs4_recoverydir());
1728        if (copied > (len - HEXDIR_LEN)) {
1729                /* just return nothing if output will be truncated */
1730                kfree(result);
1731                return NULL;
1732        }
1733
1734        copied = nfs4_make_rec_clidname(result + copied, name);
1735        if (copied) {
1736                kfree(result);
1737                return NULL;
1738        }
1739
1740        return result;
1741}
1742
1743static char *
1744nfsd4_cltrack_client_has_session(struct nfs4_client *clp)
1745{
1746        int copied;
1747        size_t len;
1748        char *result;
1749
1750        /* prefix + Y/N character + terminating NULL */
1751        len = strlen(HAS_SESSION_ENV_PREFIX) + 1 + 1;
1752
1753        result = kmalloc(len, GFP_KERNEL);
1754        if (!result)
1755                return result;
1756
1757        copied = snprintf(result, len, HAS_SESSION_ENV_PREFIX "%c",
1758                                clp->cl_minorversion ? 'Y' : 'N');
1759        if (copied >= len) {
1760                /* just return nothing if output was truncated */
1761                kfree(result);
1762                return NULL;
1763        }
1764
1765        return result;
1766}
1767
1768static char *
1769nfsd4_cltrack_grace_start(time64_t grace_start)
1770{
1771        int copied;
1772        size_t len;
1773        char *result;
1774
1775        /* prefix + max width of int64_t string + terminating NULL */
1776        len = strlen(GRACE_START_ENV_PREFIX) + 22 + 1;
1777
1778        result = kmalloc(len, GFP_KERNEL);
1779        if (!result)
1780                return result;
1781
1782        copied = snprintf(result, len, GRACE_START_ENV_PREFIX "%lld",
1783                                grace_start);
1784        if (copied >= len) {
1785                /* just return nothing if output was truncated */
1786                kfree(result);
1787                return NULL;
1788        }
1789
1790        return result;
1791}
1792
1793static int
1794nfsd4_umh_cltrack_upcall(char *cmd, char *arg, char *env0, char *env1)
1795{
1796        char *envp[3];
1797        char *argv[4];
1798        int ret;
1799
1800        if (unlikely(!cltrack_prog[0])) {
1801                dprintk("%s: cltrack_prog is disabled\n", __func__);
1802                return -EACCES;
1803        }
1804
1805        dprintk("%s: cmd: %s\n", __func__, cmd);
1806        dprintk("%s: arg: %s\n", __func__, arg ? arg : "(null)");
1807        dprintk("%s: env0: %s\n", __func__, env0 ? env0 : "(null)");
1808        dprintk("%s: env1: %s\n", __func__, env1 ? env1 : "(null)");
1809
1810        envp[0] = env0;
1811        envp[1] = env1;
1812        envp[2] = NULL;
1813
1814        argv[0] = (char *)cltrack_prog;
1815        argv[1] = cmd;
1816        argv[2] = arg;
1817        argv[3] = NULL;
1818
1819        ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
1820        /*
1821         * Disable the upcall mechanism if we're getting an ENOENT or EACCES
1822         * error. The admin can re-enable it on the fly by using sysfs
1823         * once the problem has been fixed.
1824         */
1825        if (ret == -ENOENT || ret == -EACCES) {
1826                dprintk("NFSD: %s was not found or isn't executable (%d). "
1827                        "Setting cltrack_prog to blank string!",
1828                        cltrack_prog, ret);
1829                cltrack_prog[0] = '\0';
1830        }
1831        dprintk("%s: %s return value: %d\n", __func__, cltrack_prog, ret);
1832
1833        return ret;
1834}
1835
1836static char *
1837bin_to_hex_dup(const unsigned char *src, int srclen)
1838{
1839        char *buf;
1840
1841        /* +1 for terminating NULL */
1842        buf = kzalloc((srclen * 2) + 1, GFP_KERNEL);
1843        if (!buf)
1844                return buf;
1845
1846        bin2hex(buf, src, srclen);
1847        return buf;
1848}
1849
1850static int
1851nfsd4_umh_cltrack_init(struct net *net)
1852{
1853        int ret;
1854        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1855        char *grace_start = nfsd4_cltrack_grace_start(nn->boot_time);
1856
1857        /* XXX: The usermode helper s not working in container yet. */
1858        if (net != &init_net) {
1859                pr_warn("NFSD: attempt to initialize umh client tracking in a container ignored.\n");
1860                kfree(grace_start);
1861                return -EINVAL;
1862        }
1863
1864        ret = nfsd4_umh_cltrack_upcall("init", NULL, grace_start, NULL);
1865        kfree(grace_start);
1866        if (!ret)
1867                pr_info("NFSD: Using UMH upcall client tracking operations.\n");
1868        return ret;
1869}
1870
1871static void
1872nfsd4_cltrack_upcall_lock(struct nfs4_client *clp)
1873{
1874        wait_on_bit_lock(&clp->cl_flags, NFSD4_CLIENT_UPCALL_LOCK,
1875                         TASK_UNINTERRUPTIBLE);
1876}
1877
1878static void
1879nfsd4_cltrack_upcall_unlock(struct nfs4_client *clp)
1880{
1881        smp_mb__before_atomic();
1882        clear_bit(NFSD4_CLIENT_UPCALL_LOCK, &clp->cl_flags);
1883        smp_mb__after_atomic();
1884        wake_up_bit(&clp->cl_flags, NFSD4_CLIENT_UPCALL_LOCK);
1885}
1886
1887static void
1888nfsd4_umh_cltrack_create(struct nfs4_client *clp)
1889{
1890        char *hexid, *has_session, *grace_start;
1891        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1892
1893        /*
1894         * With v4.0 clients, there's little difference in outcome between a
1895         * create and check operation, and we can end up calling into this
1896         * function multiple times per client (once for each openowner). So,
1897         * for v4.0 clients skip upcalling once the client has been recorded
1898         * on stable storage.
1899         *
1900         * For v4.1+ clients, the outcome of the two operations is different,
1901         * so we must ensure that we upcall for the create operation. v4.1+
1902         * clients call this on RECLAIM_COMPLETE though, so we should only end
1903         * up doing a single create upcall per client.
1904         */
1905        if (clp->cl_minorversion == 0 &&
1906            test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1907                return;
1908
1909        hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len);
1910        if (!hexid) {
1911                dprintk("%s: can't allocate memory for upcall!\n", __func__);
1912                return;
1913        }
1914
1915        has_session = nfsd4_cltrack_client_has_session(clp);
1916        grace_start = nfsd4_cltrack_grace_start(nn->boot_time);
1917
1918        nfsd4_cltrack_upcall_lock(clp);
1919        if (!nfsd4_umh_cltrack_upcall("create", hexid, has_session, grace_start))
1920                set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1921        nfsd4_cltrack_upcall_unlock(clp);
1922
1923        kfree(has_session);
1924        kfree(grace_start);
1925        kfree(hexid);
1926}
1927
1928static void
1929nfsd4_umh_cltrack_remove(struct nfs4_client *clp)
1930{
1931        char *hexid;
1932
1933        if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1934                return;
1935
1936        hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len);
1937        if (!hexid) {
1938                dprintk("%s: can't allocate memory for upcall!\n", __func__);
1939                return;
1940        }
1941
1942        nfsd4_cltrack_upcall_lock(clp);
1943        if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags) &&
1944            nfsd4_umh_cltrack_upcall("remove", hexid, NULL, NULL) == 0)
1945                clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1946        nfsd4_cltrack_upcall_unlock(clp);
1947
1948        kfree(hexid);
1949}
1950
1951static int
1952nfsd4_umh_cltrack_check(struct nfs4_client *clp)
1953{
1954        int ret;
1955        char *hexid, *has_session, *legacy;
1956
1957        if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1958                return 0;
1959
1960        hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len);
1961        if (!hexid) {
1962                dprintk("%s: can't allocate memory for upcall!\n", __func__);
1963                return -ENOMEM;
1964        }
1965
1966        has_session = nfsd4_cltrack_client_has_session(clp);
1967        legacy = nfsd4_cltrack_legacy_recdir(&clp->cl_name);
1968
1969        nfsd4_cltrack_upcall_lock(clp);
1970        if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) {
1971                ret = 0;
1972        } else {
1973                ret = nfsd4_umh_cltrack_upcall("check", hexid, has_session, legacy);
1974                if (ret == 0)
1975                        set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1976        }
1977        nfsd4_cltrack_upcall_unlock(clp);
1978        kfree(has_session);
1979        kfree(legacy);
1980        kfree(hexid);
1981
1982        return ret;
1983}
1984
1985static void
1986nfsd4_umh_cltrack_grace_done(struct nfsd_net *nn)
1987{
1988        char *legacy;
1989        char timestr[22]; /* FIXME: better way to determine max size? */
1990
1991        sprintf(timestr, "%lld", nn->boot_time);
1992        legacy = nfsd4_cltrack_legacy_topdir();
1993        nfsd4_umh_cltrack_upcall("gracedone", timestr, legacy, NULL);
1994        kfree(legacy);
1995}
1996
1997static const struct nfsd4_client_tracking_ops nfsd4_umh_tracking_ops = {
1998        .init           = nfsd4_umh_cltrack_init,
1999        .exit           = NULL,
2000        .create         = nfsd4_umh_cltrack_create,
2001        .remove         = nfsd4_umh_cltrack_remove,
2002        .check          = nfsd4_umh_cltrack_check,
2003        .grace_done     = nfsd4_umh_cltrack_grace_done,
2004        .version        = 1,
2005        .msglen         = 0,
2006};
2007
2008int
2009nfsd4_client_tracking_init(struct net *net)
2010{
2011        int status;
2012        struct path path;
2013        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
2014
2015        /* just run the init if it the method is already decided */
2016        if (nn->client_tracking_ops)
2017                goto do_init;
2018
2019        /* First, try to use nfsdcld */
2020        nn->client_tracking_ops = &nfsd4_cld_tracking_ops;
2021        status = nn->client_tracking_ops->init(net);
2022        if (!status)
2023                return status;
2024        if (status != -ETIMEDOUT) {
2025                nn->client_tracking_ops = &nfsd4_cld_tracking_ops_v0;
2026                status = nn->client_tracking_ops->init(net);
2027                if (!status)
2028                        return status;
2029        }
2030
2031        /*
2032         * Next, try the UMH upcall.
2033         */
2034        nn->client_tracking_ops = &nfsd4_umh_tracking_ops;
2035        status = nn->client_tracking_ops->init(net);
2036        if (!status)
2037                return status;
2038
2039        /*
2040         * Finally, See if the recoverydir exists and is a directory.
2041         * If it is, then use the legacy ops.
2042         */
2043        nn->client_tracking_ops = &nfsd4_legacy_tracking_ops;
2044        status = kern_path(nfs4_recoverydir(), LOOKUP_FOLLOW, &path);
2045        if (!status) {
2046                status = d_is_dir(path.dentry);
2047                path_put(&path);
2048                if (!status) {
2049                        status = -EINVAL;
2050                        goto out;
2051                }
2052        }
2053
2054do_init:
2055        status = nn->client_tracking_ops->init(net);
2056out:
2057        if (status) {
2058                printk(KERN_WARNING "NFSD: Unable to initialize client "
2059                                    "recovery tracking! (%d)\n", status);
2060                nn->client_tracking_ops = NULL;
2061        }
2062        return status;
2063}
2064
2065void
2066nfsd4_client_tracking_exit(struct net *net)
2067{
2068        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
2069
2070        if (nn->client_tracking_ops) {
2071                if (nn->client_tracking_ops->exit)
2072                        nn->client_tracking_ops->exit(net);
2073                nn->client_tracking_ops = NULL;
2074        }
2075}
2076
2077void
2078nfsd4_client_record_create(struct nfs4_client *clp)
2079{
2080        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
2081
2082        if (nn->client_tracking_ops)
2083                nn->client_tracking_ops->create(clp);
2084}
2085
2086void
2087nfsd4_client_record_remove(struct nfs4_client *clp)
2088{
2089        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
2090
2091        if (nn->client_tracking_ops)
2092                nn->client_tracking_ops->remove(clp);
2093}
2094
2095int
2096nfsd4_client_record_check(struct nfs4_client *clp)
2097{
2098        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
2099
2100        if (nn->client_tracking_ops)
2101                return nn->client_tracking_ops->check(clp);
2102
2103        return -EOPNOTSUPP;
2104}
2105
2106void
2107nfsd4_record_grace_done(struct nfsd_net *nn)
2108{
2109        if (nn->client_tracking_ops)
2110                nn->client_tracking_ops->grace_done(nn);
2111}
2112
2113static int
2114rpc_pipefs_event(struct notifier_block *nb, unsigned long event, void *ptr)
2115{
2116        struct super_block *sb = ptr;
2117        struct net *net = sb->s_fs_info;
2118        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
2119        struct cld_net *cn = nn->cld_net;
2120        struct dentry *dentry;
2121        int ret = 0;
2122
2123        if (!try_module_get(THIS_MODULE))
2124                return 0;
2125
2126        if (!cn) {
2127                module_put(THIS_MODULE);
2128                return 0;
2129        }
2130
2131        switch (event) {
2132        case RPC_PIPEFS_MOUNT:
2133                dentry = nfsd4_cld_register_sb(sb, cn->cn_pipe);
2134                if (IS_ERR(dentry)) {
2135                        ret = PTR_ERR(dentry);
2136                        break;
2137                }
2138                cn->cn_pipe->dentry = dentry;
2139                break;
2140        case RPC_PIPEFS_UMOUNT:
2141                if (cn->cn_pipe->dentry)
2142                        nfsd4_cld_unregister_sb(cn->cn_pipe);
2143                break;
2144        default:
2145                ret = -ENOTSUPP;
2146                break;
2147        }
2148        module_put(THIS_MODULE);
2149        return ret;
2150}
2151
2152static struct notifier_block nfsd4_cld_block = {
2153        .notifier_call = rpc_pipefs_event,
2154};
2155
2156int
2157register_cld_notifier(void)
2158{
2159        WARN_ON(!nfsd_net_id);
2160        return rpc_pipefs_notifier_register(&nfsd4_cld_block);
2161}
2162
2163void
2164unregister_cld_notifier(void)
2165{
2166        rpc_pipefs_notifier_unregister(&nfsd4_cld_block);
2167}
2168