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         /*
  68          * ip->chain fixup.  Certain duplications used to move inodes
  69          * into indirect blocks (for example) can cause ip->chain to
  70          * become stale.
  71          *
  72          *
  73          */
  74 again:
  75         chain = ip->chain;
  76         while (chain->duplink && (chain->flags & HAMMER2_CHAIN_DELETED))
  77                 chain = chain->duplink;
  78         if (chain != ip->chain) {
  79                 hammer2_chain_ref(chain);
  80                 hammer2_chain_drop(ip->chain);
  81                 ip->chain = chain;
  82         }
  83
  84         KKASSERT(chain != NULL);        /* for now */
  85         hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS);
  86
  87         /*
  88          * Resolve duplication races
  89          */
  90         if (chain->duplink && (chain->flags & HAMMER2_CHAIN_DELETED)) {
  91                 hammer2_chain_unlock(chain);
  92                 goto again;
  93         }
  94 }
  95
  96 void
  97 hammer2_inode_unlock_ex(hammer2_inode_t *ip)
  98 {
  99         hammer2_chain_t *chain;
 100
 101         /*
 102          * XXX this will catch parent directories too which we don't
 103          *     really want.
 104          */
 105         chain = ip->chain;
 106         if (chain) {
 107                 if (chain->flags & (HAMMER2_CHAIN_MODIFIED |
 108                                     HAMMER2_CHAIN_SUBMODIFIED)) {
 109                         atomic_set_int(&ip->flags, HAMMER2_INODE_MODIFIED);
 110                 }
 111                 hammer2_chain_unlock(chain);
 112         }
 113         ccms_thread_unlock(&ip->topo_cst);
 114         hammer2_inode_drop(ip);
 115 }
 116
 117 /*
 118  * NOTE: We don't combine the inode/chain lock because putting away an
 119  *       inode would otherwise confuse multiple lock holders of the inode.
 120  *
 121  *       Shared locks are especially sensitive to having too many shared
 122  *       lock counts (from the same thread) on certain paths which might
 123  *       need to upgrade them.  Only one count of a shared lock can be
 124  *       upgraded.
 125  */
 126 void
 127 hammer2_inode_lock_sh(hammer2_inode_t *ip)
 128 {
 129         hammer2_chain_t *chain;
 130
 131         hammer2_inode_ref(ip);
 132 again:
 133         ccms_thread_lock(&ip->topo_cst, CCMS_STATE_SHARED);
 134
 135         chain = ip->chain;
 136         KKASSERT(chain != NULL);        /* for now */
 137         hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS |
 138                                   HAMMER2_RESOLVE_SHARED);
 139
 140         /*
 141          * Resolve duplication races
 142          */
 143         if (chain->duplink && (chain->flags & HAMMER2_CHAIN_DELETED)) {
 144                 hammer2_chain_unlock(chain);
 145                 ccms_thread_unlock(&ip->topo_cst);
 146                 hammer2_inode_lock_ex(ip);
 147                 hammer2_inode_unlock_ex(ip);
 148                 goto again;
 149         }
 150
 151 }
 152
 153 void
 154 hammer2_inode_unlock_sh(hammer2_inode_t *ip)
 155 {
 156         if (ip->chain)
 157                 hammer2_chain_unlock(ip->chain);
 158         ccms_thread_unlock(&ip->topo_cst);
 159         hammer2_inode_drop(ip);
 160 }
 161
 162 ccms_state_t
 163 hammer2_inode_lock_temp_release(hammer2_inode_t *ip)
 164 {
 165         return(ccms_thread_lock_temp_release(&ip->topo_cst));
 166 }
 167
 168 void
 169 hammer2_inode_lock_temp_restore(hammer2_inode_t *ip, ccms_state_t ostate)
 170 {
 171         ccms_thread_lock_temp_restore(&ip->topo_cst, ostate);
 172 }
 173
 174 ccms_state_t
 175 hammer2_inode_lock_upgrade(hammer2_inode_t *ip)
 176 {
 177         return(ccms_thread_lock_upgrade(&ip->topo_cst));
 178 }
 179
 180 void
 181 hammer2_inode_lock_downgrade(hammer2_inode_t *ip, ccms_state_t ostate)
 182 {
 183         ccms_thread_lock_downgrade(&ip->topo_cst, ostate);
 184 }
 185
 186 /*
 187  * Mount-wide locks
 188  */
 189
 190 void
 191 hammer2_mount_exlock(hammer2_mount_t *hmp)
 192 {
 193         ccms_thread_lock(&hmp->vchain.core->cst, CCMS_STATE_EXCLUSIVE);
 194 }
 195
 196 void
 197 hammer2_mount_shlock(hammer2_mount_t *hmp)
 198 {
 199         ccms_thread_lock(&hmp->vchain.core->cst, CCMS_STATE_SHARED);
 200 }
 201
 202 void
 203 hammer2_mount_unlock(hammer2_mount_t *hmp)
 204 {
 205         ccms_thread_unlock(&hmp->vchain.core->cst);
 206 }
 207
 208 void
 209 hammer2_voldata_lock(hammer2_mount_t *hmp)
 210 {
 211         lockmgr(&hmp->voldatalk, LK_EXCLUSIVE);
 212 }
 213
 214 void
 215 hammer2_voldata_unlock(hammer2_mount_t *hmp, int modify)
 216 {
 217         if (modify &&
 218             (hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) == 0) {
 219                 atomic_set_int(&hmp->vchain.flags, HAMMER2_CHAIN_MODIFIED);
 220                 hammer2_chain_ref(&hmp->vchain);
 221         }
 222         lockmgr(&hmp->voldatalk, LK_RELEASE);
 223 }
 224
 225 /*
 226  * Return the directory entry type for an inode.
 227  *
 228  * ip must be locked sh/ex.
 229  */
 230 int
 231 hammer2_get_dtype(hammer2_chain_t *chain)
 232 {
 233         uint8_t type;
 234
 235         KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
 236
 237         if ((type = chain->data->ipdata.type) == HAMMER2_OBJTYPE_HARDLINK)
 238                 type = chain->data->ipdata.target_type;
 239
 240         switch(type) {
 241         case HAMMER2_OBJTYPE_UNKNOWN:
 242                 return (DT_UNKNOWN);
 243         case HAMMER2_OBJTYPE_DIRECTORY:
 244                 return (DT_DIR);
 245         case HAMMER2_OBJTYPE_REGFILE:
 246                 return (DT_REG);
 247         case HAMMER2_OBJTYPE_FIFO:
 248                 return (DT_FIFO);
 249         case HAMMER2_OBJTYPE_CDEV:      /* not supported */
 250                 return (DT_CHR);
 251         case HAMMER2_OBJTYPE_BDEV:      /* not supported */
 252                 return (DT_BLK);
 253         case HAMMER2_OBJTYPE_SOFTLINK:
 254                 return (DT_LNK);
 255         case HAMMER2_OBJTYPE_HARDLINK:  /* (never directly associated w/vp) */
 256                 return (DT_UNKNOWN);
 257         case HAMMER2_OBJTYPE_SOCKET:
 258                 return (DT_SOCK);
 259         case HAMMER2_OBJTYPE_WHITEOUT:  /* not supported */
 260                 return (DT_UNKNOWN);
 261         default:
 262                 return (DT_UNKNOWN);
 263         }
 264         /* not reached */
 265 }
 266
 267 /*
 268  * Return the directory entry type for an inode
 269  */
 270 int
 271 hammer2_get_vtype(hammer2_chain_t *chain)
 272 {
 273         KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
 274
 275         switch(chain->data->ipdata.type) {
 276         case HAMMER2_OBJTYPE_UNKNOWN:
 277                 return (VBAD);
 278         case HAMMER2_OBJTYPE_DIRECTORY:
 279                 return (VDIR);
 280         case HAMMER2_OBJTYPE_REGFILE:
 281                 return (VREG);
 282         case HAMMER2_OBJTYPE_FIFO:
 283                 return (VFIFO);
 284         case HAMMER2_OBJTYPE_CDEV:      /* not supported */
 285                 return (VCHR);
 286         case HAMMER2_OBJTYPE_BDEV:      /* not supported */
 287                 return (VBLK);
 288         case HAMMER2_OBJTYPE_SOFTLINK:
 289                 return (VLNK);
 290         case HAMMER2_OBJTYPE_HARDLINK:  /* XXX */
 291                 return (VBAD);
 292         case HAMMER2_OBJTYPE_SOCKET:
 293                 return (VSOCK);
 294         case HAMMER2_OBJTYPE_WHITEOUT:  /* not supported */
 295                 return (DT_UNKNOWN);
 296         default:
 297                 return (DT_UNKNOWN);
 298         }
 299         /* not reached */
 300 }
 301
 302 u_int8_t
 303 hammer2_get_obj_type(enum vtype vtype)
 304 {
 305         switch(vtype) {
 306         case VDIR:
 307                 return(HAMMER2_OBJTYPE_DIRECTORY);
 308         case VREG:
 309                 return(HAMMER2_OBJTYPE_REGFILE);
 310         case VFIFO:
 311                 return(HAMMER2_OBJTYPE_FIFO);
 312         case VSOCK:
 313                 return(HAMMER2_OBJTYPE_SOCKET);
 314         case VCHR:
 315                 return(HAMMER2_OBJTYPE_CDEV);
 316         case VBLK:
 317                 return(HAMMER2_OBJTYPE_BDEV);
 318         case VLNK:
 319                 return(HAMMER2_OBJTYPE_SOFTLINK);
 320         default:
 321                 return(HAMMER2_OBJTYPE_UNKNOWN);
 322         }
 323         /* not reached */
 324 }
 325
 326 /*
 327  * Convert a hammer2 64-bit time to a timespec.
 328  */
 329 void
 330 hammer2_time_to_timespec(u_int64_t xtime, struct timespec *ts)
 331 {
 332         ts->tv_sec = (unsigned long)(xtime / 1000000);
 333         ts->tv_nsec = (unsigned int)(xtime % 1000000) * 1000L;
 334 }
 335
 336 u_int64_t
 337 hammer2_timespec_to_time(struct timespec *ts)
 338 {
 339         u_int64_t xtime;
 340
 341         xtime = (unsigned)(ts->tv_nsec / 1000) +
 342                 (unsigned long)ts->tv_sec * 1000000ULL;
 343         return(xtime);
 344 }
 345
 346 /*
 347  * Convert a uuid to a unix uid or gid
 348  */
 349 u_int32_t
 350 hammer2_to_unix_xid(uuid_t *uuid)
 351 {
 352         return(*(u_int32_t *)&uuid->node[2]);
 353 }
 354
 355 void
 356 hammer2_guid_to_uuid(uuid_t *uuid, u_int32_t guid)
 357 {
 358         bzero(uuid, sizeof(*uuid));
 359         *(u_int32_t *)&uuid->node[2] = guid;
 360 }
 361
 362 /*
 363  * Borrow HAMMER1's directory hash algorithm #1 with a few modifications.
 364  * The filename is split into fields which are hashed separately and then
 365  * added together.
 366  *
 367  * Differences include: bit 63 must be set to 1 for HAMMER2 (HAMMER1 sets
 368  * it to 0), this is because bit63=0 is used for hidden hardlinked inodes.
 369  * (This means we do not need to do a 0-check/or-with-0x100000000 either).
 370  *
 371  * Also, the iscsi crc code is used instead of the old crc32 code.
 372  */
 373 hammer2_key_t
 374 hammer2_dirhash(const unsigned char *name, size_t len)
 375 {
 376         const unsigned char *aname = name;
 377         uint32_t crcx;
 378         uint64_t key;
 379         size_t i;
 380         size_t j;
 381
 382         key = 0;
 383
 384         /*
 385          * m32
 386          */
 387         crcx = 0;
 388         for (i = j = 0; i < len; ++i) {
 389                 if (aname[i] == '.' ||
 390                     aname[i] == '-' ||
 391                     aname[i] == '_' ||
 392                     aname[i] == '~') {
 393                         if (i != j)
 394                                 crcx += hammer2_icrc32(aname + j, i - j);
 395                         j = i + 1;
 396                 }
 397         }
 398         if (i != j)
 399                 crcx += hammer2_icrc32(aname + j, i - j);
 400
 401         /*
 402          * The directory hash utilizes the top 32 bits of the 64-bit key.
 403          * Bit 63 must be set to 1.
 404          */
 405         crcx |= 0x80000000U;
 406         key |= (uint64_t)crcx << 32;
 407
 408         /*
 409          * l16 - crc of entire filename
 410          *
 411          * This crc reduces degenerate hash collision conditions
 412          */
 413         crcx = hammer2_icrc32(aname, len);
 414         crcx = crcx ^ (crcx << 16);
 415         key |= crcx & 0xFFFF0000U;
 416
 417         /*
 418          * Set bit 15.  This allows readdir to strip bit 63 so a positive
 419          * 64-bit cookie/offset can always be returned, and still guarantee
 420          * that the values 0x0000-0x7FFF are available for artificial entries.
 421          * ('.' and '..').
 422          */
 423         key |= 0x8000U;
 424
 425         return (key);
 426 }
 427
 428 /*
 429  * Return the power-of-2 radix greater or equal to
 430  * the specified number of bytes.
 431  *
 432  * Always returns at least the minimum media allocation
 433  * size radix, HAMMER2_MIN_RADIX (10), which is 1KB.
 434  */
 435 int
 436 hammer2_allocsize(size_t bytes)
 437 {
 438         int radix;
 439
 440         if (bytes < HAMMER2_MIN_ALLOC)
 441                 bytes = HAMMER2_MIN_ALLOC;
 442         if (bytes == HAMMER2_PBUFSIZE)
 443                 radix = HAMMER2_PBUFRADIX;
 444         else if (bytes >= 16384)
 445                 radix = 14;
 446         else if (bytes >= 1024)
 447                 radix = 10;
 448         else
 449                 radix = HAMMER2_MIN_RADIX;
 450
 451         while (((size_t)1 << radix) < bytes)
 452                 ++radix;
 453         return (radix);
 454 }
 455
 456 /*
 457  * ip must be locked sh/ex
 458  */
 459 int
 460 hammer2_calc_logical(hammer2_inode_t *ip, hammer2_off_t uoff,
 461                      hammer2_key_t *lbasep, hammer2_key_t *leofp)
 462 {
 463         hammer2_inode_data_t *ipdata = &ip->chain->data->ipdata;
 464         int radix;
 465
 466         *lbasep = uoff & ~HAMMER2_PBUFMASK64;
 467         *leofp = ipdata->size & ~HAMMER2_PBUFMASK64;
 468         KKASSERT(*lbasep <= *leofp);
 469         if (*lbasep == *leofp /*&& *leofp < 1024 * 1024*/) {
 470                 radix = hammer2_allocsize((size_t)(ipdata->size - *leofp));
 471                 if (radix < HAMMER2_MINALLOCRADIX)
 472                         radix = HAMMER2_MINALLOCRADIX;
 473                 *leofp += 1U << radix;
 474                 return (1U << radix);
 475         } else {
 476                 return (HAMMER2_PBUFSIZE);
 477         }
 478 }
 479
 480 void
 481 hammer2_update_time(uint64_t *timep)
 482 {
 483         struct timeval tv;
 484
 485         getmicrotime(&tv);
 486         *timep = (unsigned long)tv.tv_sec * 1000000 + tv.tv_usec;
 487 }