sys/vfs/hammer2/hammer2_subr.c

   1 /*
   2  * Copyright (c) 2011-2012 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 hammer2_chain_t *
  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(ip->hmp, chain, HAMMER2_RESOLVE_ALWAYS);
  70
  71         return (chain);
  72 }
  73
  74 void
  75 hammer2_inode_unlock_ex(hammer2_inode_t *ip, hammer2_chain_t *chain)
  76 {
  77         /*
  78          * XXX this will catch parent directories too which we don't
  79          *     really want.
  80          */
  81         if (ip->chain && (ip->chain->flags & (HAMMER2_CHAIN_MODIFIED |
  82                                               HAMMER2_CHAIN_SUBMODIFIED))) {
  83                 atomic_set_int(&ip->flags, HAMMER2_INODE_MODIFIED);
  84         }
  85         if (chain)
  86                 hammer2_chain_unlock(ip->hmp, chain);
  87         ccms_thread_unlock(&ip->topo_cst);
  88         hammer2_inode_drop(ip);
  89 }
  90
  91 /*
  92  * NOTE: We don't combine the inode/chain lock because putting away an
  93  *       inode would otherwise confuse multiple lock holders of the inode.
  94  *
  95  *       Shared locks are especially sensitive to having too many shared
  96  *       lock counts (from the same thread) on certain paths which might
  97  *       need to upgrade them.  Only one count of a shared lock can be
  98  *       upgraded.
  99  */
 100 hammer2_chain_t *
 101 hammer2_inode_lock_sh(hammer2_inode_t *ip)
 102 {
 103         hammer2_chain_t *chain;
 104
 105         hammer2_inode_ref(ip);
 106         ccms_thread_lock(&ip->topo_cst, CCMS_STATE_SHARED);
 107
 108         chain = ip->chain;
 109         KKASSERT(chain != NULL);        /* for now */
 110         hammer2_chain_lock(ip->hmp, chain, HAMMER2_RESOLVE_ALWAYS |
 111                                            HAMMER2_RESOLVE_SHARED);
 112         return (chain);
 113 }
 114
 115 void
 116 hammer2_inode_unlock_sh(hammer2_inode_t *ip, hammer2_chain_t *chain)
 117 {
 118         if (chain)
 119                 hammer2_chain_unlock(ip->hmp, chain);
 120         ccms_thread_unlock(&ip->topo_cst);
 121         hammer2_inode_drop(ip);
 122 }
 123
 124 ccms_state_t
 125 hammer2_inode_lock_temp_release(hammer2_inode_t *ip)
 126 {
 127         return(ccms_thread_lock_temp_release(&ip->topo_cst));
 128 }
 129
 130 ccms_state_t
 131 hammer2_inode_lock_upgrade(hammer2_inode_t *ip)
 132 {
 133         return(ccms_thread_lock_upgrade(&ip->topo_cst));
 134 }
 135
 136 void
 137 hammer2_inode_lock_restore(hammer2_inode_t *ip, ccms_state_t ostate)
 138 {
 139         ccms_thread_lock_restore(&ip->topo_cst, ostate);
 140 }
 141
 142 /*
 143  * Mount-wide locks
 144  */
 145
 146 void
 147 hammer2_mount_exlock(hammer2_mount_t *hmp)
 148 {
 149         ccms_thread_lock(&hmp->vchain.cst, CCMS_STATE_EXCLUSIVE);
 150 }
 151
 152 void
 153 hammer2_mount_shlock(hammer2_mount_t *hmp)
 154 {
 155         ccms_thread_lock(&hmp->vchain.cst, CCMS_STATE_SHARED);
 156 }
 157
 158 void
 159 hammer2_mount_unlock(hammer2_mount_t *hmp)
 160 {
 161         ccms_thread_unlock(&hmp->vchain.cst);
 162 }
 163
 164 void
 165 hammer2_voldata_lock(hammer2_mount_t *hmp)
 166 {
 167         lockmgr(&hmp->voldatalk, LK_EXCLUSIVE);
 168 }
 169
 170 void
 171 hammer2_voldata_unlock(hammer2_mount_t *hmp)
 172 {
 173         lockmgr(&hmp->voldatalk, LK_RELEASE);
 174 }
 175
 176 /*
 177  * Return the directory entry type for an inode.
 178  *
 179  * ip must be locked sh/ex.
 180  */
 181 int
 182 hammer2_get_dtype(hammer2_chain_t *chain)
 183 {
 184         uint8_t type;
 185
 186         KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
 187
 188         if ((type = chain->data->ipdata.type) == HAMMER2_OBJTYPE_HARDLINK)
 189                 type = chain->data->ipdata.target_type;
 190
 191         switch(type) {
 192         case HAMMER2_OBJTYPE_UNKNOWN:
 193                 return (DT_UNKNOWN);
 194         case HAMMER2_OBJTYPE_DIRECTORY:
 195                 return (DT_DIR);
 196         case HAMMER2_OBJTYPE_REGFILE:
 197                 return (DT_REG);
 198         case HAMMER2_OBJTYPE_FIFO:
 199                 return (DT_FIFO);
 200         case HAMMER2_OBJTYPE_CDEV:      /* not supported */
 201                 return (DT_CHR);
 202         case HAMMER2_OBJTYPE_BDEV:      /* not supported */
 203                 return (DT_BLK);
 204         case HAMMER2_OBJTYPE_SOFTLINK:
 205                 return (DT_LNK);
 206         case HAMMER2_OBJTYPE_HARDLINK:  /* (never directly associated w/vp) */
 207                 return (DT_UNKNOWN);
 208         case HAMMER2_OBJTYPE_SOCKET:
 209                 return (DT_SOCK);
 210         case HAMMER2_OBJTYPE_WHITEOUT:  /* not supported */
 211                 return (DT_UNKNOWN);
 212         default:
 213                 return (DT_UNKNOWN);
 214         }
 215         /* not reached */
 216 }
 217
 218 /*
 219  * Return the directory entry type for an inode
 220  */
 221 int
 222 hammer2_get_vtype(hammer2_chain_t *chain)
 223 {
 224         KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
 225
 226         switch(chain->data->ipdata.type) {
 227         case HAMMER2_OBJTYPE_UNKNOWN:
 228                 return (VBAD);
 229         case HAMMER2_OBJTYPE_DIRECTORY:
 230                 return (VDIR);
 231         case HAMMER2_OBJTYPE_REGFILE:
 232                 return (VREG);
 233         case HAMMER2_OBJTYPE_FIFO:
 234                 return (VFIFO);
 235         case HAMMER2_OBJTYPE_CDEV:      /* not supported */
 236                 return (VCHR);
 237         case HAMMER2_OBJTYPE_BDEV:      /* not supported */
 238                 return (VBLK);
 239         case HAMMER2_OBJTYPE_SOFTLINK:
 240                 return (VLNK);
 241         case HAMMER2_OBJTYPE_HARDLINK:  /* XXX */
 242                 return (VBAD);
 243         case HAMMER2_OBJTYPE_SOCKET:
 244                 return (VSOCK);
 245         case HAMMER2_OBJTYPE_WHITEOUT:  /* not supported */
 246                 return (DT_UNKNOWN);
 247         default:
 248                 return (DT_UNKNOWN);
 249         }
 250         /* not reached */
 251 }
 252
 253 u_int8_t
 254 hammer2_get_obj_type(enum vtype vtype)
 255 {
 256         switch(vtype) {
 257         case VDIR:
 258                 return(HAMMER2_OBJTYPE_DIRECTORY);
 259         case VREG:
 260                 return(HAMMER2_OBJTYPE_REGFILE);
 261         case VFIFO:
 262                 return(HAMMER2_OBJTYPE_FIFO);
 263         case VSOCK:
 264                 return(HAMMER2_OBJTYPE_SOCKET);
 265         case VCHR:
 266                 return(HAMMER2_OBJTYPE_CDEV);
 267         case VBLK:
 268                 return(HAMMER2_OBJTYPE_BDEV);
 269         case VLNK:
 270                 return(HAMMER2_OBJTYPE_SOFTLINK);
 271         default:
 272                 return(HAMMER2_OBJTYPE_UNKNOWN);
 273         }
 274         /* not reached */
 275 }
 276
 277 /*
 278  * Convert a hammer2 64-bit time to a timespec.
 279  */
 280 void
 281 hammer2_time_to_timespec(u_int64_t xtime, struct timespec *ts)
 282 {
 283         ts->tv_sec = (unsigned long)(xtime / 1000000);
 284         ts->tv_nsec = (unsigned int)(xtime % 1000000) * 1000L;
 285 }
 286
 287 u_int64_t
 288 hammer2_timespec_to_time(struct timespec *ts)
 289 {
 290         u_int64_t xtime;
 291
 292         xtime = (unsigned)(ts->tv_nsec / 1000) +
 293                 (unsigned long)ts->tv_sec * 1000000ULL;
 294         return(xtime);
 295 }
 296
 297 /*
 298  * Convert a uuid to a unix uid or gid
 299  */
 300 u_int32_t
 301 hammer2_to_unix_xid(uuid_t *uuid)
 302 {
 303         return(*(u_int32_t *)&uuid->node[2]);
 304 }
 305
 306 void
 307 hammer2_guid_to_uuid(uuid_t *uuid, u_int32_t guid)
 308 {
 309         bzero(uuid, sizeof(*uuid));
 310         *(u_int32_t *)&uuid->node[2] = guid;
 311 }
 312
 313 /*
 314  * Borrow HAMMER1's directory hash algorithm #1 with a few modifications.
 315  * The filename is split into fields which are hashed separately and then
 316  * added together.
 317  *
 318  * Differences include: bit 63 must be set to 1 for HAMMER2 (HAMMER1 sets
 319  * it to 0), this is because bit63=0 is used for hidden hardlinked inodes.
 320  * (This means we do not need to do a 0-check/or-with-0x100000000 either).
 321  *
 322  * Also, the iscsi crc code is used instead of the old crc32 code.
 323  */
 324 hammer2_key_t
 325 hammer2_dirhash(const unsigned char *name, size_t len)
 326 {
 327         const unsigned char *aname = name;
 328         uint32_t crcx;
 329         uint64_t key;
 330         size_t i;
 331         size_t j;
 332
 333         key = 0;
 334
 335         /*
 336          * m32
 337          */
 338         crcx = 0;
 339         for (i = j = 0; i < len; ++i) {
 340                 if (aname[i] == '.' ||
 341                     aname[i] == '-' ||
 342                     aname[i] == '_' ||
 343                     aname[i] == '~') {
 344                         if (i != j)
 345                                 crcx += hammer2_icrc32(aname + j, i - j);
 346                         j = i + 1;
 347                 }
 348         }
 349         if (i != j)
 350                 crcx += hammer2_icrc32(aname + j, i - j);
 351
 352         /*
 353          * The directory hash utilizes the top 32 bits of the 64-bit key.
 354          * Bit 63 must be set to 1.
 355          */
 356         crcx |= 0x80000000U;
 357         key |= (uint64_t)crcx << 32;
 358
 359         /*
 360          * l16 - crc of entire filename
 361          *
 362          * This crc reduces degenerate hash collision conditions
 363          */
 364         crcx = hammer2_icrc32(aname, len);
 365         crcx = crcx ^ (crcx << 16);
 366         key |= crcx & 0xFFFF0000U;
 367
 368         /*
 369          * Set bit 15.  This allows readdir to strip bit 63 so a positive
 370          * 64-bit cookie/offset can always be returned, and still guarantee
 371          * that the values 0x0000-0x7FFF are available for artificial entries.
 372          * ('.' and '..').
 373          */
 374         key |= 0x8000U;
 375
 376         return (key);
 377 }
 378
 379 /*
 380  * Return the power-of-2 radix greater or equal to
 381  * the specified number of bytes.
 382  *
 383  * Always returns at least the minimum media allocation
 384  * size radix, HAMMER2_MIN_RADIX (10), which is 1KB.
 385  */
 386 int
 387 hammer2_allocsize(size_t bytes)
 388 {
 389         int radix;
 390
 391         if (bytes < HAMMER2_MIN_ALLOC)
 392                 bytes = HAMMER2_MIN_ALLOC;
 393         if (bytes == HAMMER2_PBUFSIZE)
 394                 radix = HAMMER2_PBUFRADIX;
 395         else if (bytes >= 16384)
 396                 radix = 14;
 397         else if (bytes >= 1024)
 398                 radix = 10;
 399         else
 400                 radix = HAMMER2_MIN_RADIX;
 401
 402         while (((size_t)1 << radix) < bytes)
 403                 ++radix;
 404         return (radix);
 405 }
 406
 407 /*
 408  * ip must be locked sh/ex
 409  */
 410 int
 411 hammer2_calc_logical(hammer2_inode_t *ip, hammer2_off_t uoff,
 412                      hammer2_key_t *lbasep, hammer2_key_t *leofp)
 413 {
 414         hammer2_inode_data_t *ipdata = &ip->chain->data->ipdata;
 415         int radix;
 416
 417         *lbasep = uoff & ~HAMMER2_PBUFMASK64;
 418         *leofp = ipdata->size & ~HAMMER2_PBUFMASK64;
 419         KKASSERT(*lbasep <= *leofp);
 420         if (*lbasep == *leofp /*&& *leofp < 1024 * 1024*/) {
 421                 radix = hammer2_allocsize((size_t)(ipdata->size - *leofp));
 422                 if (radix < HAMMER2_MINALLOCRADIX)
 423                         radix = HAMMER2_MINALLOCRADIX;
 424                 *leofp += 1U << radix;
 425                 return (1U << radix);
 426         } else {
 427                 return (HAMMER2_PBUFSIZE);
 428         }
 429 }
 430
 431 void
 432 hammer2_update_time(uint64_t *timep)
 433 {
 434         struct timeval tv;
 435
 436         getmicrotime(&tv);
 437         *timep = (unsigned long)tv.tv_sec * 1000000 + tv.tv_usec;
 438 }