sys/vfs/hammer/hammer_vfsops.c

   1 /*
   2  * Copyright (c) 2007-2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project 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 BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <sys/param.h>
  36 #include <sys/systm.h>
  37 #include <sys/kernel.h>
  38 #include <sys/vnode.h>
  39 #include <sys/mount.h>
  40 #include <sys/malloc.h>
  41 #include <sys/nlookup.h>
  42 #include <sys/fcntl.h>
  43 #include <sys/sysctl.h>
  44 #include <sys/buf.h>
  45 #include <sys/buf2.h>
  46 #include "hammer.h"
  47
  48 /*
  49  * NOTE!  Global statistics may not be MPSAFE so HAMMER never uses them
  50  *        in conditionals.
  51  */
  52 int hammer_supported_version = HAMMER_VOL_VERSION_DEFAULT;
  53 int hammer_debug_io;
  54 int hammer_debug_general;
  55 int hammer_debug_debug = 1;             /* medium-error panics */
  56 int hammer_debug_inode;
  57 int hammer_debug_locks;
  58 int hammer_debug_btree;
  59 int hammer_debug_tid;
  60 int hammer_debug_recover;               /* -1 will disable, +1 will force */
  61 int hammer_debug_recover_faults;
  62 int hammer_debug_critical;              /* non-zero enter debugger on error */
  63 int hammer_cluster_enable = 1;          /* enable read clustering by default */
  64 int hammer_live_dedup = 0;
  65 int hammer_tdmux_ticks;
  66 int hammer_count_fsyncs;
  67 int hammer_count_inodes;
  68 int hammer_count_iqueued;
  69 int hammer_count_reclaims;
  70 int hammer_count_records;
  71 int hammer_count_record_datas;
  72 int hammer_count_volumes;
  73 int hammer_count_buffers;
  74 int hammer_count_nodes;
  75 int64_t hammer_count_extra_space_used;
  76 int64_t hammer_stats_btree_lookups;
  77 int64_t hammer_stats_btree_searches;
  78 int64_t hammer_stats_btree_inserts;
  79 int64_t hammer_stats_btree_deletes;
  80 int64_t hammer_stats_btree_elements;
  81 int64_t hammer_stats_btree_splits;
  82 int64_t hammer_stats_btree_iterations;
  83 int64_t hammer_stats_btree_root_iterations;
  84 int64_t hammer_stats_record_iterations;
  85
  86 int64_t hammer_stats_file_read;
  87 int64_t hammer_stats_file_write;
  88 int64_t hammer_stats_file_iopsr;
  89 int64_t hammer_stats_file_iopsw;
  90 int64_t hammer_stats_disk_read;
  91 int64_t hammer_stats_disk_write;
  92 int64_t hammer_stats_inode_flushes;
  93 int64_t hammer_stats_commits;
  94 int64_t hammer_stats_undo;
  95 int64_t hammer_stats_redo;
  96
  97 long hammer_count_dirtybufspace;        /* global */
  98 int hammer_count_refedbufs;             /* global */
  99 int hammer_count_reservations;
 100 long hammer_count_io_running_read;
 101 long hammer_count_io_running_write;
 102 int hammer_count_io_locked;
 103 long hammer_limit_dirtybufspace;        /* per-mount */
 104 int hammer_limit_recs;                  /* as a whole XXX */
 105 int hammer_limit_inode_recs = 2048;     /* per inode */
 106 int hammer_limit_reclaims;
 107 int hammer_live_dedup_cache_size = DEDUP_CACHE_SIZE;
 108 int hammer_limit_redo = 4096 * 1024;    /* per inode */
 109 int hammer_autoflush = 500;             /* auto flush (typ on reclaim) */
 110 int hammer_bio_count;
 111 int hammer_verify_zone;
 112 int hammer_verify_data = 1;
 113 int hammer_write_mode;
 114 int hammer_double_buffer;
 115 int hammer_yield_check = 16;
 116 int hammer_fsync_mode = 3;
 117 int64_t hammer_contention_count;
 118 int64_t hammer_zone_limit;
 119
 120 /*
 121  * Live dedup debug counters (sysctls are writable so that counters
 122  * can be reset from userspace).
 123  */
 124 int64_t hammer_live_dedup_vnode_bcmps = 0;
 125 int64_t hammer_live_dedup_device_bcmps = 0;
 126 int64_t hammer_live_dedup_findblk_failures = 0;
 127 int64_t hammer_live_dedup_bmap_saves = 0;
 128
 129
 130 SYSCTL_NODE(_vfs, OID_AUTO, hammer, CTLFLAG_RW, 0, "HAMMER filesystem");
 131
 132 SYSCTL_INT(_vfs_hammer, OID_AUTO, supported_version, CTLFLAG_RD,
 133            &hammer_supported_version, 0, "");
 134 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_general, CTLFLAG_RW,
 135            &hammer_debug_general, 0, "");
 136 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_io, CTLFLAG_RW,
 137            &hammer_debug_io, 0, "");
 138 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_debug, CTLFLAG_RW,
 139            &hammer_debug_debug, 0, "");
 140 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_inode, CTLFLAG_RW,
 141            &hammer_debug_inode, 0, "");
 142 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_locks, CTLFLAG_RW,
 143            &hammer_debug_locks, 0, "");
 144 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_btree, CTLFLAG_RW,
 145            &hammer_debug_btree, 0, "");
 146 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_tid, CTLFLAG_RW,
 147            &hammer_debug_tid, 0, "");
 148 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_recover, CTLFLAG_RW,
 149            &hammer_debug_recover, 0, "");
 150 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_recover_faults, CTLFLAG_RW,
 151            &hammer_debug_recover_faults, 0, "");
 152 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_critical, CTLFLAG_RW,
 153            &hammer_debug_critical, 0, "");
 154 SYSCTL_INT(_vfs_hammer, OID_AUTO, cluster_enable, CTLFLAG_RW,
 155            &hammer_cluster_enable, 0, "");
 156 /*
 157  * 0 - live dedup is disabled
 158  * 1 - dedup cache is populated on reads only
 159  * 2 - dedup cache is populated on both reads and writes
 160  */
 161 SYSCTL_INT(_vfs_hammer, OID_AUTO, live_dedup, CTLFLAG_RD,
 162            &hammer_live_dedup, 0, "Enable live dedup (experimental)");
 163 SYSCTL_INT(_vfs_hammer, OID_AUTO, tdmux_ticks, CTLFLAG_RW,
 164            &hammer_tdmux_ticks, 0, "Hammer tdmux ticks");
 165
 166 SYSCTL_LONG(_vfs_hammer, OID_AUTO, limit_dirtybufspace, CTLFLAG_RW,
 167            &hammer_limit_dirtybufspace, 0, "");
 168 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_recs, CTLFLAG_RW,
 169            &hammer_limit_recs, 0, "");
 170 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_inode_recs, CTLFLAG_RW,
 171            &hammer_limit_inode_recs, 0, "");
 172 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_reclaims, CTLFLAG_RW,
 173            &hammer_limit_reclaims, 0, "");
 174 SYSCTL_INT(_vfs_hammer, OID_AUTO, live_dedup_cache_size, CTLFLAG_RW,
 175            &hammer_live_dedup_cache_size, 0,
 176            "Number of cache entries");
 177 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_redo, CTLFLAG_RW,
 178            &hammer_limit_redo, 0, "");
 179
 180 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_fsyncs, CTLFLAG_RD,
 181            &hammer_count_fsyncs, 0, "");
 182 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_inodes, CTLFLAG_RD,
 183            &hammer_count_inodes, 0, "");
 184 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_iqueued, CTLFLAG_RD,
 185            &hammer_count_iqueued, 0, "");
 186 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_reclaims, CTLFLAG_RD,
 187            &hammer_count_reclaims, 0, "");
 188 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_records, CTLFLAG_RD,
 189            &hammer_count_records, 0, "");
 190 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_record_datas, CTLFLAG_RD,
 191            &hammer_count_record_datas, 0, "");
 192 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_volumes, CTLFLAG_RD,
 193            &hammer_count_volumes, 0, "");
 194 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_buffers, CTLFLAG_RD,
 195            &hammer_count_buffers, 0, "");
 196 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_nodes, CTLFLAG_RD,
 197            &hammer_count_nodes, 0, "");
 198 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, count_extra_space_used, CTLFLAG_RD,
 199            &hammer_count_extra_space_used, 0, "");
 200
 201 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_searches, CTLFLAG_RD,
 202            &hammer_stats_btree_searches, 0, "");
 203 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_lookups, CTLFLAG_RD,
 204            &hammer_stats_btree_lookups, 0, "");
 205 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_inserts, CTLFLAG_RD,
 206            &hammer_stats_btree_inserts, 0, "");
 207 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_deletes, CTLFLAG_RD,
 208            &hammer_stats_btree_deletes, 0, "");
 209 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_elements, CTLFLAG_RD,
 210            &hammer_stats_btree_elements, 0, "");
 211 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_splits, CTLFLAG_RD,
 212            &hammer_stats_btree_splits, 0, "");
 213 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_iterations, CTLFLAG_RD,
 214            &hammer_stats_btree_iterations, 0, "");
 215 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_root_iterations, CTLFLAG_RD,
 216            &hammer_stats_btree_root_iterations, 0, "");
 217 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_record_iterations, CTLFLAG_RD,
 218            &hammer_stats_record_iterations, 0, "");
 219
 220 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_file_read, CTLFLAG_RD,
 221            &hammer_stats_file_read, 0, "");
 222 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_file_write, CTLFLAG_RD,
 223            &hammer_stats_file_write, 0, "");
 224 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_file_iopsr, CTLFLAG_RD,
 225            &hammer_stats_file_iopsr, 0, "");
 226 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_file_iopsw, CTLFLAG_RD,
 227            &hammer_stats_file_iopsw, 0, "");
 228 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_disk_read, CTLFLAG_RD,
 229            &hammer_stats_disk_read, 0, "");
 230 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_disk_write, CTLFLAG_RD,
 231            &hammer_stats_disk_write, 0, "");
 232 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_inode_flushes, CTLFLAG_RD,
 233            &hammer_stats_inode_flushes, 0, "");
 234 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_commits, CTLFLAG_RD,
 235            &hammer_stats_commits, 0, "");
 236 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_undo, CTLFLAG_RD,
 237            &hammer_stats_undo, 0, "");
 238 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_redo, CTLFLAG_RD,
 239            &hammer_stats_redo, 0, "");
 240
 241 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, live_dedup_vnode_bcmps, CTLFLAG_RW,
 242             &hammer_live_dedup_vnode_bcmps, 0,
 243             "successful vnode buffer comparisons");
 244 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, live_dedup_device_bcmps, CTLFLAG_RW,
 245             &hammer_live_dedup_device_bcmps, 0,
 246             "successful device buffer comparisons");
 247 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, live_dedup_findblk_failures, CTLFLAG_RW,
 248             &hammer_live_dedup_findblk_failures, 0,
 249             "block lookup failures for comparison");
 250 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, live_dedup_bmap_saves, CTLFLAG_RW,
 251             &hammer_live_dedup_bmap_saves, 0,
 252             "useful physical block lookups");
 253
 254 SYSCTL_LONG(_vfs_hammer, OID_AUTO, count_dirtybufspace, CTLFLAG_RD,
 255            &hammer_count_dirtybufspace, 0, "");
 256 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_refedbufs, CTLFLAG_RD,
 257            &hammer_count_refedbufs, 0, "");
 258 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_reservations, CTLFLAG_RD,
 259            &hammer_count_reservations, 0, "");
 260 SYSCTL_LONG(_vfs_hammer, OID_AUTO, count_io_running_read, CTLFLAG_RD,
 261            &hammer_count_io_running_read, 0, "");
 262 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_io_locked, CTLFLAG_RD,
 263            &hammer_count_io_locked, 0, "");
 264 SYSCTL_LONG(_vfs_hammer, OID_AUTO, count_io_running_write, CTLFLAG_RD,
 265            &hammer_count_io_running_write, 0, "");
 266 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, zone_limit, CTLFLAG_RW,
 267            &hammer_zone_limit, 0, "");
 268 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, contention_count, CTLFLAG_RW,
 269            &hammer_contention_count, 0, "");
 270 SYSCTL_INT(_vfs_hammer, OID_AUTO, autoflush, CTLFLAG_RW,
 271            &hammer_autoflush, 0, "");
 272 SYSCTL_INT(_vfs_hammer, OID_AUTO, verify_zone, CTLFLAG_RW,
 273            &hammer_verify_zone, 0, "");
 274 SYSCTL_INT(_vfs_hammer, OID_AUTO, verify_data, CTLFLAG_RW,
 275            &hammer_verify_data, 0, "");
 276 SYSCTL_INT(_vfs_hammer, OID_AUTO, write_mode, CTLFLAG_RW,
 277            &hammer_write_mode, 0, "");
 278 SYSCTL_INT(_vfs_hammer, OID_AUTO, double_buffer, CTLFLAG_RW,
 279            &hammer_double_buffer, 0, "");
 280 SYSCTL_INT(_vfs_hammer, OID_AUTO, yield_check, CTLFLAG_RW,
 281            &hammer_yield_check, 0, "");
 282 SYSCTL_INT(_vfs_hammer, OID_AUTO, fsync_mode, CTLFLAG_RW,
 283            &hammer_fsync_mode, 0, "");
 284
 285 /* KTR_INFO_MASTER(hammer); */
 286
 287 /*
 288  * VFS ABI
 289  */
 290 static void     hammer_free_hmp(struct mount *mp);
 291
 292 static int      hammer_vfs_mount(struct mount *mp, char *path, caddr_t data,
 293                                 struct ucred *cred);
 294 static int      hammer_vfs_unmount(struct mount *mp, int mntflags);
 295 static int      hammer_vfs_root(struct mount *mp, struct vnode **vpp);
 296 static int      hammer_vfs_statfs(struct mount *mp, struct statfs *sbp,
 297                                 struct ucred *cred);
 298 static int      hammer_vfs_statvfs(struct mount *mp, struct statvfs *sbp,
 299                                 struct ucred *cred);
 300 static int      hammer_vfs_sync(struct mount *mp, int waitfor);
 301 static int      hammer_vfs_vget(struct mount *mp, struct vnode *dvp,
 302                                 ino_t ino, struct vnode **vpp);
 303 static int      hammer_vfs_init(struct vfsconf *conf);
 304 static int      hammer_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
 305                                 struct fid *fhp, struct vnode **vpp);
 306 static int      hammer_vfs_vptofh(struct vnode *vp, struct fid *fhp);
 307 static int      hammer_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
 308                                 int *exflagsp, struct ucred **credanonp);
 309
 310
 311 static struct vfsops hammer_vfsops = {
 312         .vfs_mount      = hammer_vfs_mount,
 313         .vfs_unmount    = hammer_vfs_unmount,
 314         .vfs_root       = hammer_vfs_root,
 315         .vfs_statfs     = hammer_vfs_statfs,
 316         .vfs_statvfs    = hammer_vfs_statvfs,
 317         .vfs_sync       = hammer_vfs_sync,
 318         .vfs_vget       = hammer_vfs_vget,
 319         .vfs_init       = hammer_vfs_init,
 320         .vfs_vptofh     = hammer_vfs_vptofh,
 321         .vfs_fhtovp     = hammer_vfs_fhtovp,
 322         .vfs_checkexp   = hammer_vfs_checkexp
 323 };
 324
 325 MALLOC_DEFINE(M_HAMMER, "HAMMER-mount", "");
 326
 327 VFS_SET(hammer_vfsops, hammer, 0);
 328 MODULE_VERSION(hammer, 1);
 329
 330 static int
 331 hammer_vfs_init(struct vfsconf *conf)
 332 {
 333         long n;
 334
 335         /*
 336          * Wait up to this long for an exclusive deadlock to clear
 337          * before acquiring a new shared lock on the ip.  The deadlock
 338          * may have occured on a b-tree node related to the ip.
 339          */
 340         if (hammer_tdmux_ticks == 0)
 341                 hammer_tdmux_ticks = hz / 5;
 342
 343         /*
 344          * Autosize, but be careful because a hammer filesystem's
 345          * reserve is partially calculated based on dirtybufspace,
 346          * so we simply cannot allow it to get too large.
 347          */
 348         if (hammer_limit_recs == 0) {
 349                 n = nbuf * 25;
 350                 if (n > kmalloc_limit(M_HAMMER) / 512)
 351                         n = kmalloc_limit(M_HAMMER) / 512;
 352                 if (n > 2 * 1024 * 1024)
 353                         n = 2 * 1024 * 1024;
 354                 hammer_limit_recs = (int)n;
 355         }
 356         if (hammer_limit_dirtybufspace == 0) {
 357                 hammer_limit_dirtybufspace = hidirtybufspace / 2;
 358                 if (hammer_limit_dirtybufspace < 1L * 1024 * 1024)
 359                         hammer_limit_dirtybufspace = 1024L * 1024;
 360                 if (hammer_limit_dirtybufspace > 1024L * 1024 * 1024)
 361                         hammer_limit_dirtybufspace = 1024L * 1024 * 1024;
 362         }
 363
 364         /*
 365          * The hammer_inode structure detaches from the vnode on reclaim.
 366          * This limits the number of inodes in this state to prevent a
 367          * memory pool blowout.
 368          */
 369         if (hammer_limit_reclaims == 0)
 370                 hammer_limit_reclaims = desiredvnodes / 10;
 371
 372         return(0);
 373 }
 374
 375 static int
 376 hammer_vfs_mount(struct mount *mp, char *mntpt, caddr_t data,
 377                  struct ucred *cred)
 378 {
 379         struct hammer_mount_info info;
 380         hammer_mount_t hmp;
 381         hammer_volume_t rootvol;
 382         struct vnode *rootvp;
 383         struct vnode *devvp = NULL;
 384         const char *upath;      /* volume name in userspace */
 385         char *path;             /* volume name in system space */
 386         int error;
 387         int i;
 388         int master_id;
 389         char *next_volume_ptr = NULL;
 390
 391         /*
 392          * Accept hammer_mount_info.  mntpt is NULL for root mounts at boot.
 393          */
 394         if (mntpt == NULL) {
 395                 bzero(&info, sizeof(info));
 396                 info.asof = 0;
 397                 info.hflags = 0;
 398                 info.nvolumes = 1;
 399
 400                 next_volume_ptr = mp->mnt_stat.f_mntfromname;
 401
 402                 /* Count number of volumes separated by ':' */
 403                 for (char *p = next_volume_ptr; *p != '\0'; ++p) {
 404                         if (*p == ':') {
 405                                 ++info.nvolumes;
 406                         }
 407                 }
 408
 409                 mp->mnt_flag &= ~MNT_RDONLY; /* mount R/W */
 410         } else {
 411                 if ((error = copyin(data, &info, sizeof(info))) != 0)
 412                         return (error);
 413         }
 414
 415         /*
 416          * updating or new mount
 417          */
 418         if (mp->mnt_flag & MNT_UPDATE) {
 419                 hmp = (void *)mp->mnt_data;
 420                 KKASSERT(hmp != NULL);
 421         } else {
 422                 if (info.nvolumes <= 0 || info.nvolumes >= 32768)
 423                         return (EINVAL);
 424                 hmp = NULL;
 425         }
 426
 427         /*
 428          * master-id validation.  The master id may not be changed by a
 429          * mount update.
 430          */
 431         if (info.hflags & HMNT_MASTERID) {
 432                 if (hmp && hmp->master_id != info.master_id) {
 433                         kprintf("hammer: cannot change master id "
 434                                 "with mount update\n");
 435                         return(EINVAL);
 436                 }
 437                 master_id = info.master_id;
 438                 if (master_id < -1 || master_id >= HAMMER_MAX_MASTERS)
 439                         return (EINVAL);
 440         } else {
 441                 if (hmp)
 442                         master_id = hmp->master_id;
 443                 else
 444                         master_id = 0;
 445         }
 446
 447         /*
 448          * Internal mount data structure
 449          */
 450         if (hmp == NULL) {
 451                 hmp = kmalloc(sizeof(*hmp), M_HAMMER, M_WAITOK | M_ZERO);
 452                 mp->mnt_data = (qaddr_t)hmp;
 453                 hmp->mp = mp;
 454                 /*TAILQ_INIT(&hmp->recycle_list);*/
 455
 456                 /*
 457                  * Make sure kmalloc type limits are set appropriately.
 458                  *
 459                  * Our inode kmalloc group is sized based on maxvnodes
 460                  * (controlled by the system, not us).
 461                  */
 462                 kmalloc_create(&hmp->m_misc, "HAMMER-others");
 463                 kmalloc_create(&hmp->m_inodes, "HAMMER-inodes");
 464
 465                 kmalloc_raise_limit(hmp->m_inodes, 0);  /* unlimited */
 466
 467                 hmp->root_btree_beg.localization = 0x00000000U;
 468                 hmp->root_btree_beg.obj_id = -0x8000000000000000LL;
 469                 hmp->root_btree_beg.key = -0x8000000000000000LL;
 470                 hmp->root_btree_beg.create_tid = 1;
 471                 hmp->root_btree_beg.delete_tid = 1;
 472                 hmp->root_btree_beg.rec_type = 0;
 473                 hmp->root_btree_beg.obj_type = 0;
 474
 475                 hmp->root_btree_end.localization = 0xFFFFFFFFU;
 476                 hmp->root_btree_end.obj_id = 0x7FFFFFFFFFFFFFFFLL;
 477                 hmp->root_btree_end.key = 0x7FFFFFFFFFFFFFFFLL;
 478                 hmp->root_btree_end.create_tid = 0xFFFFFFFFFFFFFFFFULL;
 479                 hmp->root_btree_end.delete_tid = 0;   /* special case */
 480                 hmp->root_btree_end.rec_type = 0xFFFFU;
 481                 hmp->root_btree_end.obj_type = 0;
 482
 483                 hmp->krate.freq = 1;    /* maximum reporting rate (hz) */
 484                 hmp->krate.count = -16; /* initial burst */
 485
 486                 hmp->sync_lock.refs = 1;
 487                 hmp->free_lock.refs = 1;
 488                 hmp->undo_lock.refs = 1;
 489                 hmp->blkmap_lock.refs = 1;
 490                 hmp->snapshot_lock.refs = 1;
 491                 hmp->volume_lock.refs = 1;
 492
 493                 TAILQ_INIT(&hmp->delay_list);
 494                 TAILQ_INIT(&hmp->flush_group_list);
 495                 TAILQ_INIT(&hmp->objid_cache_list);
 496                 TAILQ_INIT(&hmp->undo_lru_list);
 497                 TAILQ_INIT(&hmp->reclaim_list);
 498
 499                 RB_INIT(&hmp->rb_dedup_crc_root);
 500                 RB_INIT(&hmp->rb_dedup_off_root);
 501                 TAILQ_INIT(&hmp->dedup_lru_list);
 502         }
 503         hmp->hflags &= ~HMNT_USERFLAGS;
 504         hmp->hflags |= info.hflags & HMNT_USERFLAGS;
 505
 506         hmp->master_id = master_id;
 507
 508         if (info.asof) {
 509                 mp->mnt_flag |= MNT_RDONLY;
 510                 hmp->asof = info.asof;
 511         } else {
 512                 hmp->asof = HAMMER_MAX_TID;
 513         }
 514
 515         hmp->volume_to_remove = -1;
 516
 517         /*
 518          * Re-open read-write if originally read-only, or vise-versa.
 519          *
 520          * When going from read-only to read-write execute the stage2
 521          * recovery if it has not already been run.
 522          */
 523         if (mp->mnt_flag & MNT_UPDATE) {
 524                 lwkt_gettoken(&hmp->fs_token);
 525                 error = 0;
 526                 if (hmp->ronly && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
 527                         kprintf("HAMMER read-only -> read-write\n");
 528                         hmp->ronly = 0;
 529                         RB_SCAN(hammer_vol_rb_tree, &hmp->rb_vols_root, NULL,
 530                                 hammer_adjust_volume_mode, NULL);
 531                         rootvol = hammer_get_root_volume(hmp, &error);
 532                         if (rootvol) {
 533                                 hammer_recover_flush_buffers(hmp, rootvol, 1);
 534                                 error = hammer_recover_stage2(hmp, rootvol);
 535                                 bcopy(rootvol->ondisk->vol0_blockmap,
 536                                       hmp->blockmap,
 537                                       sizeof(hmp->blockmap));
 538                                 hammer_rel_volume(rootvol, 0);
 539                         }
 540                         RB_SCAN(hammer_ino_rb_tree, &hmp->rb_inos_root, NULL,
 541                                 hammer_reload_inode, NULL);
 542                         /* kernel clears MNT_RDONLY */
 543                 } else if (hmp->ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
 544                         kprintf("HAMMER read-write -> read-only\n");
 545                         hmp->ronly = 1; /* messy */
 546                         RB_SCAN(hammer_ino_rb_tree, &hmp->rb_inos_root, NULL,
 547                                 hammer_reload_inode, NULL);
 548                         hmp->ronly = 0;
 549                         hammer_flusher_sync(hmp);
 550                         hammer_flusher_sync(hmp);
 551                         hammer_flusher_sync(hmp);
 552                         hmp->ronly = 1;
 553                         RB_SCAN(hammer_vol_rb_tree, &hmp->rb_vols_root, NULL,
 554                                 hammer_adjust_volume_mode, NULL);
 555                 }
 556                 lwkt_reltoken(&hmp->fs_token);
 557                 return(error);
 558         }
 559
 560         RB_INIT(&hmp->rb_vols_root);
 561         RB_INIT(&hmp->rb_inos_root);
 562         RB_INIT(&hmp->rb_redo_root);
 563         RB_INIT(&hmp->rb_nods_root);
 564         RB_INIT(&hmp->rb_undo_root);
 565         RB_INIT(&hmp->rb_resv_root);
 566         RB_INIT(&hmp->rb_bufs_root);
 567         RB_INIT(&hmp->rb_pfsm_root);
 568
 569         hmp->ronly = ((mp->mnt_flag & MNT_RDONLY) != 0);
 570
 571         RB_INIT(&hmp->volu_root);
 572         RB_INIT(&hmp->undo_root);
 573         RB_INIT(&hmp->data_root);
 574         RB_INIT(&hmp->meta_root);
 575         RB_INIT(&hmp->lose_root);
 576         TAILQ_INIT(&hmp->iorun_list);
 577
 578         lwkt_token_init(&hmp->fs_token, "hammerfs");
 579         lwkt_token_init(&hmp->io_token, "hammerio");
 580
 581         lwkt_gettoken(&hmp->fs_token);
 582
 583         /*
 584          * Load volumes
 585          */
 586         path = objcache_get(namei_oc, M_WAITOK);
 587         hmp->nvolumes = -1;
 588         for (i = 0; i < info.nvolumes; ++i) {
 589                 if (mntpt == NULL) {
 590                         /*
 591                          * Root mount.
 592                          */
 593                         KKASSERT(next_volume_ptr != NULL);
 594                         strcpy(path, "");
 595                         if (*next_volume_ptr != '/') {
 596                                 /* relative path */
 597                                 strcpy(path, "/dev/");
 598                         }
 599                         int k;
 600                         for (k = strlen(path); k < MAXPATHLEN-1; ++k) {
 601                                 if (*next_volume_ptr == '\0') {
 602                                         break;
 603                                 } else if (*next_volume_ptr == ':') {
 604                                         ++next_volume_ptr;
 605                                         break;
 606                                 } else {
 607                                         path[k] = *next_volume_ptr;
 608                                         ++next_volume_ptr;
 609                                 }
 610                         }
 611                         path[k] = '\0';
 612
 613                         error = 0;
 614                         cdev_t dev = kgetdiskbyname(path);
 615                         error = bdevvp(dev, &devvp);
 616                         if (error) {
 617                                 kprintf("hammer_mountroot: can't find devvp\n");
 618                         }
 619                 } else {
 620                         error = copyin(&info.volumes[i], &upath,
 621                                        sizeof(char *));
 622                         if (error == 0)
 623                                 error = copyinstr(upath, path,
 624                                                   MAXPATHLEN, NULL);
 625                 }
 626                 if (error == 0)
 627                         error = hammer_install_volume(hmp, path, devvp);
 628                 if (error)
 629                         break;
 630         }
 631         objcache_put(namei_oc, path);
 632
 633         /*
 634          * Make sure we found a root volume
 635          */
 636         if (error == 0 && hmp->rootvol == NULL) {
 637                 kprintf("hammer_mount: No root volume found!\n");
 638                 error = EINVAL;
 639         }
 640
 641         /*
 642          * Check that all required volumes are available
 643          */
 644         if (error == 0 && hammer_mountcheck_volumes(hmp)) {
 645                 kprintf("hammer_mount: Missing volumes, cannot mount!\n");
 646                 error = EINVAL;
 647         }
 648
 649         if (error) {
 650                 /* called with fs_token held */
 651                 hammer_free_hmp(mp);
 652                 return (error);
 653         }
 654
 655         /*
 656          * No errors, setup enough of the mount point so we can lookup the
 657          * root vnode.
 658          */
 659         mp->mnt_iosize_max = MAXPHYS;
 660         mp->mnt_kern_flag |= MNTK_FSMID;
 661
 662         /*
 663          * MPSAFE code.  Note that VOPs and VFSops which are not MPSAFE
 664          * will acquire a per-mount token prior to entry and release it
 665          * on return, so even if we do not specify it we no longer get
 666          * the BGL regardlless of how we are flagged.
 667          */
 668         mp->mnt_kern_flag |= MNTK_ALL_MPSAFE;
 669         /*MNTK_RD_MPSAFE | MNTK_GA_MPSAFE | MNTK_IN_MPSAFE;*/
 670
 671         /*
 672          * note: f_iosize is used by vnode_pager_haspage() when constructing
 673          * its VOP_BMAP call.
 674          */
 675         mp->mnt_stat.f_iosize = HAMMER_BUFSIZE;
 676         mp->mnt_stat.f_bsize = HAMMER_BUFSIZE;
 677
 678         mp->mnt_vstat.f_frsize = HAMMER_BUFSIZE;
 679         mp->mnt_vstat.f_bsize = HAMMER_BUFSIZE;
 680
 681         mp->mnt_maxsymlinklen = 255;
 682         mp->mnt_flag |= MNT_LOCAL;
 683
 684         vfs_add_vnodeops(mp, &hammer_vnode_vops, &mp->mnt_vn_norm_ops);
 685         vfs_add_vnodeops(mp, &hammer_spec_vops, &mp->mnt_vn_spec_ops);
 686         vfs_add_vnodeops(mp, &hammer_fifo_vops, &mp->mnt_vn_fifo_ops);
 687
 688         /*
 689          * The root volume's ondisk pointer is only valid if we hold a
 690          * reference to it.
 691          */
 692         rootvol = hammer_get_root_volume(hmp, &error);
 693         if (error)
 694                 goto failed;
 695
 696         /*
 697          * Perform any necessary UNDO operations.  The recovery code does
 698          * call hammer_undo_lookup() so we have to pre-cache the blockmap,
 699          * and then re-copy it again after recovery is complete.
 700          *
 701          * If this is a read-only mount the UNDO information is retained
 702          * in memory in the form of dirty buffer cache buffers, and not
 703          * written back to the media.
 704          */
 705         bcopy(rootvol->ondisk->vol0_blockmap, hmp->blockmap,
 706               sizeof(hmp->blockmap));
 707
 708         /*
 709          * Check filesystem version
 710          */
 711         hmp->version = rootvol->ondisk->vol_version;
 712         if (hmp->version < HAMMER_VOL_VERSION_MIN ||
 713             hmp->version > HAMMER_VOL_VERSION_MAX) {
 714                 kprintf("HAMMER: mount unsupported fs version %d\n",
 715                         hmp->version);
 716                 error = ERANGE;
 717                 goto done;
 718         }
 719
 720         /*
 721          * The undo_rec_limit limits the size of flush groups to avoid
 722          * blowing out the UNDO FIFO.  This calculation is typically in
 723          * the tens of thousands and is designed primarily when small
 724          * HAMMER filesystems are created.
 725          */
 726         hmp->undo_rec_limit = hammer_undo_max(hmp) / 8192 + 100;
 727         if (hammer_debug_general & 0x0001)
 728                 kprintf("HAMMER: undo_rec_limit %d\n", hmp->undo_rec_limit);
 729
 730         /*
 731          * NOTE: Recover stage1 not only handles meta-data recovery, it
 732          *       also sets hmp->undo_seqno for HAMMER VERSION 4+ filesystems.
 733          */
 734         error = hammer_recover_stage1(hmp, rootvol);
 735         if (error) {
 736                 kprintf("Failed to recover HAMMER filesystem on mount\n");
 737                 goto done;
 738         }
 739
 740         /*
 741          * Finish setup now that we have a good root volume.
 742          *
 743          * The top 16 bits of fsid.val[1] is a pfs id.
 744          */
 745         ksnprintf(mp->mnt_stat.f_mntfromname,
 746                   sizeof(mp->mnt_stat.f_mntfromname), "%s",
 747                   rootvol->ondisk->vol_name);
 748         mp->mnt_stat.f_fsid.val[0] =
 749                 crc32((char *)&rootvol->ondisk->vol_fsid + 0, 8);
 750         mp->mnt_stat.f_fsid.val[1] =
 751                 crc32((char *)&rootvol->ondisk->vol_fsid + 8, 8);
 752         mp->mnt_stat.f_fsid.val[1] &= 0x0000FFFF;
 753
 754         mp->mnt_vstat.f_fsid_uuid = rootvol->ondisk->vol_fsid;
 755         mp->mnt_vstat.f_fsid = crc32(&mp->mnt_vstat.f_fsid_uuid,
 756                                      sizeof(mp->mnt_vstat.f_fsid_uuid));
 757
 758         /*
 759          * Certain often-modified fields in the root volume are cached in
 760          * the hammer_mount structure so we do not have to generate lots
 761          * of little UNDO structures for them.
 762          *
 763          * Recopy after recovery.  This also has the side effect of
 764          * setting our cached undo FIFO's first_offset, which serves to
 765          * placemark the FIFO start for the NEXT flush cycle while the
 766          * on-disk first_offset represents the LAST flush cycle.
 767          */
 768         hmp->next_tid = rootvol->ondisk->vol0_next_tid;
 769         hmp->flush_tid1 = hmp->next_tid;
 770         hmp->flush_tid2 = hmp->next_tid;
 771         bcopy(rootvol->ondisk->vol0_blockmap, hmp->blockmap,
 772               sizeof(hmp->blockmap));
 773         hmp->copy_stat_freebigblocks = rootvol->ondisk->vol0_stat_freebigblocks;
 774
 775         hammer_flusher_create(hmp);
 776
 777         /*
 778          * Locate the root directory using the root cluster's B-Tree as a
 779          * starting point.  The root directory uses an obj_id of 1.
 780          *
 781          * FUTURE: Leave the root directory cached referenced but unlocked
 782          * in hmp->rootvp (need to flush it on unmount).
 783          */
 784         error = hammer_vfs_vget(mp, NULL, 1, &rootvp);
 785         if (error)
 786                 goto done;
 787         vput(rootvp);
 788         /*vn_unlock(hmp->rootvp);*/
 789         if (hmp->ronly == 0)
 790                 error = hammer_recover_stage2(hmp, rootvol);
 791
 792         /*
 793          * If the stage2 recovery fails be sure to clean out all cached
 794          * vnodes before throwing away the mount structure or bad things
 795          * will happen.
 796          */
 797         if (error)
 798                 vflush(mp, 0, 0);
 799
 800 done:
 801         if ((mp->mnt_flag & MNT_UPDATE) == 0) {
 802                 /* New mount */
 803
 804                 /* Populate info for mount point (NULL pad)*/
 805                 bzero(mp->mnt_stat.f_mntonname, MNAMELEN);
 806                 size_t size;
 807                 if (mntpt) {
 808                         copyinstr(mntpt, mp->mnt_stat.f_mntonname,
 809                                                         MNAMELEN -1, &size);
 810                 } else { /* Root mount */
 811                         mp->mnt_stat.f_mntonname[0] = '/';
 812                 }
 813         }
 814         (void)VFS_STATFS(mp, &mp->mnt_stat, cred);
 815         hammer_rel_volume(rootvol, 0);
 816 failed:
 817         /*
 818          * Cleanup and return.
 819          */
 820         if (error) {
 821                 /* called with fs_token held */
 822                 hammer_free_hmp(mp);
 823         } else {
 824                 lwkt_reltoken(&hmp->fs_token);
 825         }
 826         return (error);
 827 }
 828
 829 static int
 830 hammer_vfs_unmount(struct mount *mp, int mntflags)
 831 {
 832         hammer_mount_t hmp = (void *)mp->mnt_data;
 833         int flags;
 834         int error;
 835
 836         /*
 837          * Clean out the vnodes
 838          */
 839         lwkt_gettoken(&hmp->fs_token);
 840         flags = 0;
 841         if (mntflags & MNT_FORCE)
 842                 flags |= FORCECLOSE;
 843         error = vflush(mp, 0, flags);
 844
 845         /*
 846          * Clean up the internal mount structure and related entities.  This
 847          * may issue I/O.
 848          */
 849         if (error == 0) {
 850                 /* called with fs_token held */
 851                 hammer_free_hmp(mp);
 852         } else {
 853                 lwkt_reltoken(&hmp->fs_token);
 854         }
 855         return(error);
 856 }
 857
 858 /*
 859  * Clean up the internal mount structure and disassociate it from the mount.
 860  * This may issue I/O.
 861  *
 862  * Called with fs_token held.
 863  */
 864 static void
 865 hammer_free_hmp(struct mount *mp)
 866 {
 867         hammer_mount_t hmp = (void *)mp->mnt_data;
 868         hammer_flush_group_t flg;
 869         int count;
 870         int dummy;
 871
 872         /*
 873          * Flush anything dirty.  This won't even run if the
 874          * filesystem errored-out.
 875          */
 876         count = 0;
 877         while (hammer_flusher_haswork(hmp)) {
 878                 hammer_flusher_sync(hmp);
 879                 ++count;
 880                 if (count >= 5) {
 881                         if (count == 5)
 882                                 kprintf("HAMMER: umount flushing.");
 883                         else
 884                                 kprintf(".");
 885                         tsleep(&dummy, 0, "hmrufl", hz);
 886                 }
 887                 if (count == 30) {
 888                         kprintf("giving up\n");
 889                         break;
 890                 }
 891         }
 892         if (count >= 5 && count < 30)
 893                 kprintf("\n");
 894
 895         /*
 896          * If the mount had a critical error we have to destroy any
 897          * remaining inodes before we can finish cleaning up the flusher.
 898          */
 899         if (hmp->flags & HAMMER_MOUNT_CRITICAL_ERROR) {
 900                 RB_SCAN(hammer_ino_rb_tree, &hmp->rb_inos_root, NULL,
 901                         hammer_destroy_inode_callback, NULL);
 902         }
 903
 904         /*
 905          * There shouldn't be any inodes left now and any left over
 906          * flush groups should now be empty.
 907          */
 908         KKASSERT(RB_EMPTY(&hmp->rb_inos_root));
 909         while ((flg = TAILQ_FIRST(&hmp->flush_group_list)) != NULL) {
 910                 TAILQ_REMOVE(&hmp->flush_group_list, flg, flush_entry);
 911                 KKASSERT(RB_EMPTY(&flg->flush_tree));
 912                 if (flg->refs) {
 913                         kprintf("HAMMER: Warning, flush_group %p was "
 914                                 "not empty on umount!\n", flg);
 915                 }
 916                 kfree(flg, hmp->m_misc);
 917         }
 918
 919         /*
 920          * We can finally destroy the flusher
 921          */
 922         hammer_flusher_destroy(hmp);
 923
 924         /*
 925          * We may have held recovered buffers due to a read-only mount.
 926          * These must be discarded.
 927          */
 928         if (hmp->ronly)
 929                 hammer_recover_flush_buffers(hmp, NULL, -1);
 930
 931         /*
 932          * Unload buffers and then volumes
 933          */
 934         RB_SCAN(hammer_buf_rb_tree, &hmp->rb_bufs_root, NULL,
 935                 hammer_unload_buffer, NULL);
 936         RB_SCAN(hammer_vol_rb_tree, &hmp->rb_vols_root, NULL,
 937                 hammer_unload_volume, NULL);
 938
 939         mp->mnt_data = NULL;
 940         mp->mnt_flag &= ~MNT_LOCAL;
 941         hmp->mp = NULL;
 942         hammer_destroy_objid_cache(hmp);
 943         hammer_destroy_dedup_cache(hmp);
 944         if (hmp->dedup_free_cache != NULL) {
 945                 kfree(hmp->dedup_free_cache, hmp->m_misc);
 946                 hmp->dedup_free_cache = NULL;
 947         }
 948         kmalloc_destroy(&hmp->m_misc);
 949         kmalloc_destroy(&hmp->m_inodes);
 950         lwkt_reltoken(&hmp->fs_token);
 951         kfree(hmp, M_HAMMER);
 952 }
 953
 954 /*
 955  * Report critical errors.  ip may be NULL.
 956  */
 957 void
 958 hammer_critical_error(hammer_mount_t hmp, hammer_inode_t ip,
 959                       int error, const char *msg)
 960 {
 961         hmp->flags |= HAMMER_MOUNT_CRITICAL_ERROR;
 962
 963         krateprintf(&hmp->krate,
 964                     "HAMMER(%s): Critical error inode=%jd error=%d %s\n",
 965                     hmp->mp->mnt_stat.f_mntfromname,
 966                     (intmax_t)(ip ? ip->obj_id : -1),
 967                     error, msg);
 968
 969         if (hmp->ronly == 0) {
 970                 hmp->ronly = 2;         /* special errored read-only mode */
 971                 hmp->mp->mnt_flag |= MNT_RDONLY;
 972                 RB_SCAN(hammer_vol_rb_tree, &hmp->rb_vols_root, NULL,
 973                         hammer_adjust_volume_mode, NULL);
 974                 kprintf("HAMMER(%s): Forcing read-only mode\n",
 975                         hmp->mp->mnt_stat.f_mntfromname);
 976         }
 977         hmp->error = error;
 978         if (hammer_debug_critical)
 979                 Debugger("Entering debugger");
 980 }
 981
 982
 983 /*
 984  * Obtain a vnode for the specified inode number.  An exclusively locked
 985  * vnode is returned.
 986  */
 987 int
 988 hammer_vfs_vget(struct mount *mp, struct vnode *dvp,
 989                 ino_t ino, struct vnode **vpp)
 990 {
 991         struct hammer_transaction trans;
 992         struct hammer_mount *hmp = (void *)mp->mnt_data;
 993         struct hammer_inode *ip;
 994         int error;
 995         u_int32_t localization;
 996
 997         lwkt_gettoken(&hmp->fs_token);
 998         hammer_simple_transaction(&trans, hmp);
 999
1000         /*
1001          * If a directory vnode is supplied (mainly NFS) then we can acquire
1002          * the PFS domain from it.  Otherwise we would only be able to vget
1003          * inodes in the root PFS.
1004          */
1005         if (dvp) {
1006                 localization = HAMMER_DEF_LOCALIZATION +
1007                                 VTOI(dvp)->obj_localization;
1008         } else {
1009                 localization = HAMMER_DEF_LOCALIZATION;
1010         }
1011
1012         /*
1013          * Lookup the requested HAMMER inode.  The structure must be
1014          * left unlocked while we manipulate the related vnode to avoid
1015          * a deadlock.
1016          */
1017         ip = hammer_get_inode(&trans, NULL, ino,
1018                               hmp->asof, localization,
1019                               0, &error);
1020         if (ip == NULL) {
1021                 *vpp = NULL;
1022         } else {
1023                 error = hammer_get_vnode(ip, vpp);
1024                 hammer_rel_inode(ip, 0);
1025         }
1026         hammer_done_transaction(&trans);
1027         lwkt_reltoken(&hmp->fs_token);
1028         return (error);
1029 }
1030
1031 /*
1032  * Return the root vnode for the filesystem.
1033  *
1034  * HAMMER stores the root vnode in the hammer_mount structure so
1035  * getting it is easy.
1036  */
1037 static int
1038 hammer_vfs_root(struct mount *mp, struct vnode **vpp)
1039 {
1040         int error;
1041
1042         error = hammer_vfs_vget(mp, NULL, 1, vpp);
1043         return (error);
1044 }
1045
1046 static int
1047 hammer_vfs_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
1048 {
1049         struct hammer_mount *hmp = (void *)mp->mnt_data;
1050         hammer_volume_t volume;
1051         hammer_volume_ondisk_t ondisk;
1052         int error;
1053         int64_t bfree;
1054         int64_t breserved;
1055
1056         lwkt_gettoken(&hmp->fs_token);
1057         volume = hammer_get_root_volume(hmp, &error);
1058         if (error) {
1059                 lwkt_reltoken(&hmp->fs_token);
1060                 return(error);
1061         }
1062         ondisk = volume->ondisk;
1063
1064         /*
1065          * Basic stats
1066          */
1067         _hammer_checkspace(hmp, HAMMER_CHKSPC_WRITE, &breserved);
1068         mp->mnt_stat.f_files = ondisk->vol0_stat_inodes;
1069         bfree = ondisk->vol0_stat_freebigblocks * HAMMER_LARGEBLOCK_SIZE;
1070         hammer_rel_volume(volume, 0);
1071
1072         mp->mnt_stat.f_bfree = (bfree - breserved) / HAMMER_BUFSIZE;
1073         mp->mnt_stat.f_bavail = mp->mnt_stat.f_bfree;
1074         if (mp->mnt_stat.f_files < 0)
1075                 mp->mnt_stat.f_files = 0;
1076
1077         *sbp = mp->mnt_stat;
1078         lwkt_reltoken(&hmp->fs_token);
1079         return(0);
1080 }
1081
1082 static int
1083 hammer_vfs_statvfs(struct mount *mp, struct statvfs *sbp, struct ucred *cred)
1084 {
1085         struct hammer_mount *hmp = (void *)mp->mnt_data;
1086         hammer_volume_t volume;
1087         hammer_volume_ondisk_t ondisk;
1088         int error;
1089         int64_t bfree;
1090         int64_t breserved;
1091
1092         lwkt_gettoken(&hmp->fs_token);
1093         volume = hammer_get_root_volume(hmp, &error);
1094         if (error) {
1095                 lwkt_reltoken(&hmp->fs_token);
1096                 return(error);
1097         }
1098         ondisk = volume->ondisk;
1099
1100         /*
1101          * Basic stats
1102          */
1103         _hammer_checkspace(hmp, HAMMER_CHKSPC_WRITE, &breserved);
1104         mp->mnt_vstat.f_files = ondisk->vol0_stat_inodes;
1105         bfree = ondisk->vol0_stat_freebigblocks * HAMMER_LARGEBLOCK_SIZE;
1106         hammer_rel_volume(volume, 0);
1107
1108         mp->mnt_vstat.f_bfree = (bfree - breserved) / HAMMER_BUFSIZE;
1109         mp->mnt_vstat.f_bavail = mp->mnt_vstat.f_bfree;
1110         if (mp->mnt_vstat.f_files < 0)
1111                 mp->mnt_vstat.f_files = 0;
1112         *sbp = mp->mnt_vstat;
1113         lwkt_reltoken(&hmp->fs_token);
1114         return(0);
1115 }
1116
1117 /*
1118  * Sync the filesystem.  Currently we have to run it twice, the second
1119  * one will advance the undo start index to the end index, so if a crash
1120  * occurs no undos will be run on mount.
1121  *
1122  * We do not sync the filesystem if we are called from a panic.  If we did
1123  * we might end up blowing up a sync that was already in progress.
1124  */
1125 static int
1126 hammer_vfs_sync(struct mount *mp, int waitfor)
1127 {
1128         struct hammer_mount *hmp = (void *)mp->mnt_data;
1129         int error;
1130
1131         lwkt_gettoken(&hmp->fs_token);
1132         if (panicstr == NULL) {
1133                 error = hammer_sync_hmp(hmp, waitfor);
1134         } else {
1135                 error = EIO;
1136         }
1137         lwkt_reltoken(&hmp->fs_token);
1138         return (error);
1139 }
1140
1141 /*
1142  * Convert a vnode to a file handle.
1143  *
1144  * Accesses read-only fields on already-referenced structures so
1145  * no token is needed.
1146  */
1147 static int
1148 hammer_vfs_vptofh(struct vnode *vp, struct fid *fhp)
1149 {
1150         hammer_inode_t ip;
1151
1152         KKASSERT(MAXFIDSZ >= 16);
1153         ip = VTOI(vp);
1154         fhp->fid_len = offsetof(struct fid, fid_data[16]);
1155         fhp->fid_ext = ip->obj_localization >> 16;
1156         bcopy(&ip->obj_id, fhp->fid_data + 0, sizeof(ip->obj_id));
1157         bcopy(&ip->obj_asof, fhp->fid_data + 8, sizeof(ip->obj_asof));
1158         return(0);
1159 }
1160
1161
1162 /*
1163  * Convert a file handle back to a vnode.
1164  *
1165  * Use rootvp to enforce PFS isolation when a PFS is exported via a
1166  * null mount.
1167  */
1168 static int
1169 hammer_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
1170                   struct fid *fhp, struct vnode **vpp)
1171 {
1172         hammer_mount_t hmp = (void *)mp->mnt_data;
1173         struct hammer_transaction trans;
1174         struct hammer_inode *ip;
1175         struct hammer_inode_info info;
1176         int error;
1177         u_int32_t localization;
1178
1179         bcopy(fhp->fid_data + 0, &info.obj_id, sizeof(info.obj_id));
1180         bcopy(fhp->fid_data + 8, &info.obj_asof, sizeof(info.obj_asof));
1181         if (rootvp)
1182                 localization = VTOI(rootvp)->obj_localization;
1183         else
1184                 localization = (u_int32_t)fhp->fid_ext << 16;
1185
1186         lwkt_gettoken(&hmp->fs_token);
1187         hammer_simple_transaction(&trans, hmp);
1188
1189         /*
1190          * Get/allocate the hammer_inode structure.  The structure must be
1191          * unlocked while we manipulate the related vnode to avoid a
1192          * deadlock.
1193          */
1194         ip = hammer_get_inode(&trans, NULL, info.obj_id,
1195                               info.obj_asof, localization, 0, &error);
1196         if (ip) {
1197                 error = hammer_get_vnode(ip, vpp);
1198                 hammer_rel_inode(ip, 0);
1199         } else {
1200                 *vpp = NULL;
1201         }
1202         hammer_done_transaction(&trans);
1203         lwkt_reltoken(&hmp->fs_token);
1204         return (error);
1205 }
1206
1207 static int
1208 hammer_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
1209                     int *exflagsp, struct ucred **credanonp)
1210 {
1211         hammer_mount_t hmp = (void *)mp->mnt_data;
1212         struct netcred *np;
1213         int error;
1214
1215         lwkt_gettoken(&hmp->fs_token);
1216         np = vfs_export_lookup(mp, &hmp->export, nam);
1217         if (np) {
1218                 *exflagsp = np->netc_exflags;
1219                 *credanonp = &np->netc_anon;
1220                 error = 0;
1221         } else {
1222                 error = EACCES;
1223         }
1224         lwkt_reltoken(&hmp->fs_token);
1225         return (error);
1226
1227 }
1228
1229 int
1230 hammer_vfs_export(struct mount *mp, int op, const struct export_args *export)
1231 {
1232         hammer_mount_t hmp = (void *)mp->mnt_data;
1233         int error;
1234
1235         lwkt_gettoken(&hmp->fs_token);
1236
1237         switch(op) {
1238         case MOUNTCTL_SET_EXPORT:
1239                 error = vfs_export(mp, &hmp->export, export);
1240                 break;
1241         default:
1242                 error = EOPNOTSUPP;
1243                 break;
1244         }
1245         lwkt_reltoken(&hmp->fs_token);
1246
1247         return(error);
1248 }
1249