sys/vfs/hammer2/hammer2_subr.c

   1 /*
   2  * Copyright (c) 2011-2013 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@dragonflybsd.org>
   6  * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org>
   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
  16  *    the documentation and/or other materials provided with the
  17  *    distribution.
  18  * 3. Neither the name of The DragonFly Project nor the names of its
  19  *    contributors may be used to endorse or promote products derived
  20  *    from this software without specific, prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  26  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  28  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  30  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35 #include <sys/cdefs.h>
  36 #include <sys/param.h>
  37 #include <sys/systm.h>
  38 #include <sys/types.h>
  39 #include <sys/lock.h>
  40 #include <sys/uuid.h>
  41 #include <sys/dirent.h>
  42
  43 #include "hammer2.h"
  44
  45 /*
  46  * HAMMER2 inode locks
  47  *
  48  * HAMMER2 offers shared locks and exclusive locks on inodes.
  49  *
  50  * An inode's ip->chain pointer is resolved and stable while an inode is
  51  * locked, and can be cleaned out at any time (become NULL) when an inode
  52  * is not locked.
  53  *
  54  * The underlying chain is also locked and returned.
  55  *
  56  * NOTE: We don't combine the inode/chain lock because putting away an
  57  *       inode would otherwise confuse multiple lock holders of the inode.
  58  */
  59 void
  60 hammer2_inode_lock_ex(hammer2_inode_t *ip)
  61 {
  62         hammer2_chain_t *chain;
  63
  64         hammer2_inode_ref(ip);
  65         ccms_thread_lock(&ip->topo_cst, CCMS_STATE_EXCLUSIVE);
  66
  67         chain = ip->chain;
  68         KKASSERT(chain != NULL);        /* for now */
  69         hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS);
  70 }
  71
  72 void
  73 hammer2_inode_unlock_ex(hammer2_inode_t *ip)
  74 {
  75         hammer2_chain_t *chain;
  76
  77         /*
  78          * XXX this will catch parent directories too which we don't
  79          *     really want.
  80          */
  81         chain = ip->chain;
  82         if (chain) {
  83                 if (chain->flags & (HAMMER2_CHAIN_MODIFIED |
  84                                     HAMMER2_CHAIN_SUBMODIFIED)) {
  85                         atomic_set_int(&ip->flags, HAMMER2_INODE_MODIFIED);
  86                 }
  87                 hammer2_chain_unlock(chain);
  88         }
  89         ccms_thread_unlock(&ip->topo_cst);
  90         hammer2_inode_drop(ip);
  91 }
  92
  93 /*
  94  * NOTE: We don't combine the inode/chain lock because putting away an
  95  *       inode would otherwise confuse multiple lock holders of the inode.
  96  *
  97  *       Shared locks are especially sensitive to having too many shared
  98  *       lock counts (from the same thread) on certain paths which might
  99  *       need to upgrade them.  Only one count of a shared lock can be
 100  *       upgraded.
 101  */
 102 void
 103 hammer2_inode_lock_sh(hammer2_inode_t *ip)
 104 {
 105         hammer2_chain_t *chain;
 106
 107         hammer2_inode_ref(ip);
 108         ccms_thread_lock(&ip->topo_cst, CCMS_STATE_SHARED);
 109
 110         chain = ip->chain;
 111         KKASSERT(chain != NULL);        /* for now */
 112         hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS |
 113                                   HAMMER2_RESOLVE_SHARED);
 114
 115 }
 116
 117 void
 118 hammer2_inode_unlock_sh(hammer2_inode_t *ip)
 119 {
 120         if (ip->chain)
 121                 hammer2_chain_unlock(ip->chain);
 122         ccms_thread_unlock(&ip->topo_cst);
 123         hammer2_inode_drop(ip);
 124 }
 125
 126 ccms_state_t
 127 hammer2_inode_lock_temp_release(hammer2_inode_t *ip)
 128 {
 129         return(ccms_thread_lock_temp_release(&ip->topo_cst));
 130 }
 131
 132 ccms_state_t
 133 hammer2_inode_lock_upgrade(hammer2_inode_t *ip)
 134 {
 135         return(ccms_thread_lock_upgrade(&ip->topo_cst));
 136 }
 137
 138 void
 139 hammer2_inode_lock_restore(hammer2_inode_t *ip, ccms_state_t ostate)
 140 {
 141         ccms_thread_lock_restore(&ip->topo_cst, ostate);
 142 }
 143
 144 /*
 145  * Mount-wide locks
 146  */
 147
 148 void
 149 hammer2_mount_exlock(hammer2_mount_t *hmp)
 150 {
 151         ccms_thread_lock(&hmp->vchain.core->cst, CCMS_STATE_EXCLUSIVE);
 152 }
 153
 154 void
 155 hammer2_mount_shlock(hammer2_mount_t *hmp)
 156 {
 157         ccms_thread_lock(&hmp->vchain.core->cst, CCMS_STATE_SHARED);
 158 }
 159
 160 void
 161 hammer2_mount_unlock(hammer2_mount_t *hmp)
 162 {
 163         ccms_thread_unlock(&hmp->vchain.core->cst);
 164 }
 165
 166 void
 167 hammer2_voldata_lock(hammer2_mount_t *hmp)
 168 {
 169         lockmgr(&hmp->voldatalk, LK_EXCLUSIVE);
 170 }
 171
 172 void
 173 hammer2_voldata_unlock(hammer2_mount_t *hmp, int modify)
 174 {
 175         if (modify &&
 176             (hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) == 0) {
 177                 atomic_set_int(&hmp->vchain.flags, HAMMER2_CHAIN_MODIFIED);
 178                 hammer2_chain_ref(&hmp->vchain);
 179         }
 180         lockmgr(&hmp->voldatalk, LK_RELEASE);
 181 }
 182
 183 /*
 184  * Return the directory entry type for an inode.
 185  *
 186  * ip must be locked sh/ex.
 187  */
 188 int
 189 hammer2_get_dtype(hammer2_chain_t *chain)
 190 {
 191         uint8_t type;
 192
 193         KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
 194
 195         if ((type = chain->data->ipdata.type) == HAMMER2_OBJTYPE_HARDLINK)
 196                 type = chain->data->ipdata.target_type;
 197
 198         switch(type) {
 199         case HAMMER2_OBJTYPE_UNKNOWN:
 200                 return (DT_UNKNOWN);
 201         case HAMMER2_OBJTYPE_DIRECTORY:
 202                 return (DT_DIR);
 203         case HAMMER2_OBJTYPE_REGFILE:
 204                 return (DT_REG);
 205         case HAMMER2_OBJTYPE_FIFO:
 206                 return (DT_FIFO);
 207         case HAMMER2_OBJTYPE_CDEV:      /* not supported */
 208                 return (DT_CHR);
 209         case HAMMER2_OBJTYPE_BDEV:      /* not supported */
 210                 return (DT_BLK);
 211         case HAMMER2_OBJTYPE_SOFTLINK:
 212                 return (DT_LNK);
 213         case HAMMER2_OBJTYPE_HARDLINK:  /* (never directly associated w/vp) */
 214                 return (DT_UNKNOWN);
 215         case HAMMER2_OBJTYPE_SOCKET:
 216                 return (DT_SOCK);
 217         case HAMMER2_OBJTYPE_WHITEOUT:  /* not supported */
 218                 return (DT_UNKNOWN);
 219         default:
 220                 return (DT_UNKNOWN);
 221         }
 222         /* not reached */
 223 }
 224
 225 /*
 226  * Return the directory entry type for an inode
 227  */
 228 int
 229 hammer2_get_vtype(hammer2_chain_t *chain)
 230 {
 231         KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
 232
 233         switch(chain->data->ipdata.type) {
 234         case HAMMER2_OBJTYPE_UNKNOWN:
 235                 return (VBAD);
 236         case HAMMER2_OBJTYPE_DIRECTORY:
 237                 return (VDIR);
 238         case HAMMER2_OBJTYPE_REGFILE:
 239                 return (VREG);
 240         case HAMMER2_OBJTYPE_FIFO:
 241                 return (VFIFO);
 242         case HAMMER2_OBJTYPE_CDEV:      /* not supported */
 243                 return (VCHR);
 244         case HAMMER2_OBJTYPE_BDEV:      /* not supported */
 245                 return (VBLK);
 246         case HAMMER2_OBJTYPE_SOFTLINK:
 247                 return (VLNK);
 248         case HAMMER2_OBJTYPE_HARDLINK:  /* XXX */
 249                 return (VBAD);
 250         case HAMMER2_OBJTYPE_SOCKET:
 251                 return (VSOCK);
 252         case HAMMER2_OBJTYPE_WHITEOUT:  /* not supported */
 253                 return (DT_UNKNOWN);
 254         default:
 255                 return (DT_UNKNOWN);
 256         }
 257         /* not reached */
 258 }
 259
 260 u_int8_t
 261 hammer2_get_obj_type(enum vtype vtype)
 262 {
 263         switch(vtype) {
 264         case VDIR:
 265                 return(HAMMER2_OBJTYPE_DIRECTORY);
 266         case VREG:
 267                 return(HAMMER2_OBJTYPE_REGFILE);
 268         case VFIFO:
 269                 return(HAMMER2_OBJTYPE_FIFO);
 270         case VSOCK:
 271                 return(HAMMER2_OBJTYPE_SOCKET);
 272         case VCHR:
 273                 return(HAMMER2_OBJTYPE_CDEV);
 274         case VBLK:
 275                 return(HAMMER2_OBJTYPE_BDEV);
 276         case VLNK:
 277                 return(HAMMER2_OBJTYPE_SOFTLINK);
 278         default:
 279                 return(HAMMER2_OBJTYPE_UNKNOWN);
 280         }
 281         /* not reached */
 282 }
 283
 284 /*
 285  * Convert a hammer2 64-bit time to a timespec.
 286  */
 287 void
 288 hammer2_time_to_timespec(u_int64_t xtime, struct timespec *ts)
 289 {
 290         ts->tv_sec = (unsigned long)(xtime / 1000000);
 291         ts->tv_nsec = (unsigned int)(xtime % 1000000) * 1000L;
 292 }
 293
 294 u_int64_t
 295 hammer2_timespec_to_time(struct timespec *ts)
 296 {
 297         u_int64_t xtime;
 298
 299         xtime = (unsigned)(ts->tv_nsec / 1000) +
 300                 (unsigned long)ts->tv_sec * 1000000ULL;
 301         return(xtime);
 302 }
 303
 304 /*
 305  * Convert a uuid to a unix uid or gid
 306  */
 307 u_int32_t
 308 hammer2_to_unix_xid(uuid_t *uuid)
 309 {
 310         return(*(u_int32_t *)&uuid->node[2]);
 311 }
 312
 313 void
 314 hammer2_guid_to_uuid(uuid_t *uuid, u_int32_t guid)
 315 {
 316         bzero(uuid, sizeof(*uuid));
 317         *(u_int32_t *)&uuid->node[2] = guid;
 318 }
 319
 320 /*
 321  * Borrow HAMMER1's directory hash algorithm #1 with a few modifications.
 322  * The filename is split into fields which are hashed separately and then
 323  * added together.
 324  *
 325  * Differences include: bit 63 must be set to 1 for HAMMER2 (HAMMER1 sets
 326  * it to 0), this is because bit63=0 is used for hidden hardlinked inodes.
 327  * (This means we do not need to do a 0-check/or-with-0x100000000 either).
 328  *
 329  * Also, the iscsi crc code is used instead of the old crc32 code.
 330  */
 331 hammer2_key_t
 332 hammer2_dirhash(const unsigned char *name, size_t len)
 333 {
 334         const unsigned char *aname = name;
 335         uint32_t crcx;
 336         uint64_t key;
 337         size_t i;
 338         size_t j;
 339
 340         key = 0;
 341
 342         /*
 343          * m32
 344          */
 345         crcx = 0;
 346         for (i = j = 0; i < len; ++i) {
 347                 if (aname[i] == '.' ||
 348                     aname[i] == '-' ||
 349                     aname[i] == '_' ||
 350                     aname[i] == '~') {
 351                         if (i != j)
 352                                 crcx += hammer2_icrc32(aname + j, i - j);
 353                         j = i + 1;
 354                 }
 355         }
 356         if (i != j)
 357                 crcx += hammer2_icrc32(aname + j, i - j);
 358
 359         /*
 360          * The directory hash utilizes the top 32 bits of the 64-bit key.
 361          * Bit 63 must be set to 1.
 362          */
 363         crcx |= 0x80000000U;
 364         key |= (uint64_t)crcx << 32;
 365
 366         /*
 367          * l16 - crc of entire filename
 368          *
 369          * This crc reduces degenerate hash collision conditions
 370          */
 371         crcx = hammer2_icrc32(aname, len);
 372         crcx = crcx ^ (crcx << 16);
 373         key |= crcx & 0xFFFF0000U;
 374
 375         /*
 376          * Set bit 15.  This allows readdir to strip bit 63 so a positive
 377          * 64-bit cookie/offset can always be returned, and still guarantee
 378          * that the values 0x0000-0x7FFF are available for artificial entries.
 379          * ('.' and '..').
 380          */
 381         key |= 0x8000U;
 382
 383         return (key);
 384 }
 385
 386 /*
 387  * Return the power-of-2 radix greater or equal to
 388  * the specified number of bytes.
 389  *
 390  * Always returns at least the minimum media allocation
 391  * size radix, HAMMER2_MIN_RADIX (10), which is 1KB.
 392  */
 393 int
 394 hammer2_allocsize(size_t bytes)
 395 {
 396         int radix;
 397
 398         if (bytes < HAMMER2_MIN_ALLOC)
 399                 bytes = HAMMER2_MIN_ALLOC;
 400         if (bytes == HAMMER2_PBUFSIZE)
 401                 radix = HAMMER2_PBUFRADIX;
 402         else if (bytes >= 16384)
 403                 radix = 14;
 404         else if (bytes >= 1024)
 405                 radix = 10;
 406         else
 407                 radix = HAMMER2_MIN_RADIX;
 408
 409         while (((size_t)1 << radix) < bytes)
 410                 ++radix;
 411         return (radix);
 412 }
 413
 414 /*
 415  * ip must be locked sh/ex
 416  */
 417 int
 418 hammer2_calc_logical(hammer2_inode_t *ip, hammer2_off_t uoff,
 419                      hammer2_key_t *lbasep, hammer2_key_t *leofp)
 420 {
 421         hammer2_inode_data_t *ipdata = &ip->chain->data->ipdata;
 422         int radix;
 423
 424         *lbasep = uoff & ~HAMMER2_PBUFMASK64;
 425         *leofp = ipdata->size & ~HAMMER2_PBUFMASK64;
 426         KKASSERT(*lbasep <= *leofp);
 427         if (*lbasep == *leofp /*&& *leofp < 1024 * 1024*/) {
 428                 radix = hammer2_allocsize((size_t)(ipdata->size - *leofp));
 429                 if (radix < HAMMER2_MINALLOCRADIX)
 430                         radix = HAMMER2_MINALLOCRADIX;
 431                 *leofp += 1U << radix;
 432                 return (1U << radix);
 433         } else {
 434                 return (HAMMER2_PBUFSIZE);
 435         }
 436 }
 437
 438 void
 439 hammer2_update_time(uint64_t *timep)
 440 {
 441         struct timeval tv;
 442
 443         getmicrotime(&tv);
 444         *timep = (unsigned long)tv.tv_sec * 1000000 + tv.tv_usec;
 445 }