sys/vfs/hammer2/hammer2_inode.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
  42 #include "hammer2.h"
  43
  44 /*
  45  * Adding a ref to an inode is only legal if the inode already has at least
  46  * one ref.
  47  */
  48 void
  49 hammer2_inode_ref(hammer2_inode_t *ip)
  50 {
  51         hammer2_chain_ref(ip->hmp, &ip->chain);
  52 }
  53
  54 /*
  55  * Drop an inode reference, freeing the inode when the last reference goes
  56  * away.
  57  */
  58 void
  59 hammer2_inode_drop(hammer2_inode_t *ip)
  60 {
  61         hammer2_chain_drop(ip->hmp, &ip->chain);
  62 }
  63
  64 /*
  65  * Get the vnode associated with the given inode, allocating the vnode if
  66  * necessary.
  67  *
  68  * Great care must be taken to avoid deadlocks and vnode acquisition/reclaim
  69  * races.
  70  *
  71  * The vnode will be returned exclusively locked and referenced.  The
  72  * reference on the vnode prevents it from being reclaimed.
  73  *
  74  * The inode (ip) must be referenced by the caller and not locked to avoid
  75  * it getting ripped out from under us or deadlocked.
  76  */
  77 struct vnode *
  78 hammer2_igetv(hammer2_inode_t *ip, int *errorp)
  79 {
  80         struct vnode *vp;
  81         hammer2_pfsmount_t *pmp;
  82
  83         pmp = ip->pmp;
  84         KKASSERT(pmp != NULL);
  85         *errorp = 0;
  86
  87         for (;;) {
  88                 /*
  89                  * Attempt to reuse an existing vnode assignment.  It is
  90                  * possible to race a reclaim so the vget() may fail.  The
  91                  * inode must be unlocked during the vget() to avoid a
  92                  * deadlock against a reclaim.
  93                  */
  94                 vp = ip->vp;
  95                 if (vp) {
  96                         /*
  97                          * Lock the inode and check for a reclaim race
  98                          */
  99                         hammer2_inode_lock_ex(ip);
 100                         if (ip->vp != vp) {
 101                                 hammer2_inode_unlock_ex(ip);
 102                                 continue;
 103                         }
 104
 105                         /*
 106                          * Inode must be unlocked during the vget() to avoid
 107                          * possible deadlocks, vnode is held to prevent
 108                          * destruction during the vget().  The vget() can
 109                          * still fail if we lost a reclaim race on the vnode.
 110                          */
 111                         vhold_interlocked(vp);
 112                         hammer2_inode_unlock_ex(ip);
 113                         if (vget(vp, LK_EXCLUSIVE)) {
 114                                 vdrop(vp);
 115                                 continue;
 116                         }
 117                         vdrop(vp);
 118                         /* vp still locked and ref from vget */
 119                         *errorp = 0;
 120                         break;
 121                 }
 122
 123                 /*
 124                  * No vnode exists, allocate a new vnode.  Beware of
 125                  * allocation races.  This function will return an
 126                  * exclusively locked and referenced vnode.
 127                  */
 128                 *errorp = getnewvnode(VT_HAMMER2, pmp->mp, &vp, 0, 0);
 129                 if (*errorp) {
 130                         vp = NULL;
 131                         break;
 132                 }
 133
 134                 /*
 135                  * Lock the inode and check for an allocation race.
 136                  */
 137                 hammer2_inode_lock_ex(ip);
 138                 if (ip->vp != NULL) {
 139                         vp->v_type = VBAD;
 140                         vx_put(vp);
 141                         hammer2_inode_unlock_ex(ip);
 142                         continue;
 143                 }
 144
 145                 switch (ip->ip_data.type) {
 146                 case HAMMER2_OBJTYPE_DIRECTORY:
 147                         vp->v_type = VDIR;
 148                         break;
 149                 case HAMMER2_OBJTYPE_REGFILE:
 150                         vp->v_type = VREG;
 151                         vinitvmio(vp, ip->ip_data.size,
 152                                   HAMMER2_LBUFSIZE,
 153                                   (int)ip->ip_data.size & HAMMER2_LBUFMASK);
 154                         break;
 155                 case HAMMER2_OBJTYPE_SOFTLINK:
 156                         /*
 157                          * XXX for now we are using the generic file_read
 158                          * and file_write code so we need a buffer cache
 159                          * association.
 160                          */
 161                         vp->v_type = VLNK;
 162                         vinitvmio(vp, ip->ip_data.size,
 163                                   HAMMER2_LBUFSIZE,
 164                                   (int)ip->ip_data.size & HAMMER2_LBUFMASK);
 165                         break;
 166                 /* XXX FIFO */
 167                 default:
 168                         panic("hammer2: unhandled objtype %d",
 169                               ip->ip_data.type);
 170                         break;
 171                 }
 172
 173                 if (ip == pmp->iroot)
 174                         vsetflags(vp, VROOT);
 175
 176                 vp->v_data = ip;
 177                 ip->vp = vp;
 178                 hammer2_chain_ref(ip->hmp, &ip->chain); /* vp association */
 179                 hammer2_inode_unlock_ex(ip);
 180                 break;
 181         }
 182
 183         /*
 184          * Return non-NULL vp and *errorp == 0, or NULL vp and *errorp != 0.
 185          */
 186         if (hammer2_debug & 0x0002) {
 187                 kprintf("igetv vp %p refs %d aux %d\n",
 188                         vp, vp->v_sysref.refcnt, vp->v_auxrefs);
 189         }
 190         return (vp);
 191 }
 192
 193 /*
 194  * Create a new inode in the specified directory using the vattr to
 195  * figure out the type of inode.
 196  *
 197  * If no error occurs the new inode with its chain locked is returned in
 198  * *nipp, otherwise an error is returned and *nipp is set to NULL.
 199  *
 200  * If vap and/or cred are NULL the related fields are not set and the
 201  * inode type defaults to a directory.  This is used when creating PFSs
 202  * under the super-root, so the inode number is set to 1 in this case.
 203  */
 204 int
 205 hammer2_inode_create(hammer2_inode_t *dip,
 206                      struct vattr *vap, struct ucred *cred,
 207                      const uint8_t *name, size_t name_len,
 208                      hammer2_inode_t **nipp)
 209 {
 210         hammer2_mount_t *hmp = dip->hmp;
 211         hammer2_chain_t *chain;
 212         hammer2_chain_t *parent;
 213         hammer2_inode_t *nip;
 214         hammer2_key_t lhc;
 215         int error;
 216         uid_t xuid;
 217
 218         lhc = hammer2_dirhash(name, name_len);
 219
 220         /*
 221          * Locate the inode or indirect block to create the new
 222          * entry in.  At the same time check for key collisions
 223          * and iterate until we don't get one.
 224          */
 225         parent = &dip->chain;
 226         hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 227
 228         error = 0;
 229         while (error == 0) {
 230                 chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
 231                 if (chain == NULL)
 232                         break;
 233                 if ((lhc & HAMMER2_DIRHASH_VISIBLE) == 0)
 234                         error = ENOSPC;
 235                 if ((lhc & HAMMER2_DIRHASH_LOMASK) == HAMMER2_DIRHASH_LOMASK)
 236                         error = ENOSPC;
 237                 hammer2_chain_unlock(hmp, chain);
 238                 chain = NULL;
 239                 ++lhc;
 240         }
 241         if (error == 0) {
 242                 chain = hammer2_chain_create(hmp, parent, NULL, lhc, 0,
 243                                              HAMMER2_BREF_TYPE_INODE,
 244                                              HAMMER2_INODE_BYTES);
 245                 if (chain == NULL)
 246                         error = EIO;
 247         }
 248         hammer2_chain_unlock(hmp, parent);
 249
 250         /*
 251          * Handle the error case
 252          */
 253         if (error) {
 254                 KKASSERT(chain == NULL);
 255                 *nipp = NULL;
 256                 return (error);
 257         }
 258
 259         /*
 260          * Set up the new inode
 261          */
 262         nip = chain->u.ip;
 263         *nipp = nip;
 264
 265         hammer2_voldata_lock(hmp);
 266         if (vap) {
 267                 nip->ip_data.type = hammer2_get_obj_type(vap->va_type);
 268                 nip->ip_data.inum = hmp->voldata.alloc_tid++;
 269                 /* XXX modify/lock */
 270         } else {
 271                 nip->ip_data.type = HAMMER2_OBJTYPE_DIRECTORY;
 272                 nip->ip_data.inum = 1;
 273         }
 274         hammer2_voldata_unlock(hmp);
 275         nip->ip_data.version = HAMMER2_INODE_VERSION_ONE;
 276         hammer2_update_time(&nip->ip_data.ctime);
 277         nip->ip_data.mtime = nip->ip_data.ctime;
 278         if (vap)
 279                 nip->ip_data.mode = vap->va_mode;
 280         nip->ip_data.nlinks = 1;
 281         if (vap) {
 282                 if (dip) {
 283                         xuid = hammer2_to_unix_xid(&dip->ip_data.uid);
 284                         xuid = vop_helper_create_uid(dip->pmp->mp,
 285                                                      dip->ip_data.mode,
 286                                                      xuid,
 287                                                      cred,
 288                                                      &vap->va_mode);
 289                 } else {
 290                         xuid = 0;
 291                 }
 292                 if (vap->va_vaflags & VA_UID_UUID_VALID)
 293                         nip->ip_data.uid = vap->va_uid_uuid;
 294                 else if (vap->va_uid != (uid_t)VNOVAL)
 295                         hammer2_guid_to_uuid(&nip->ip_data.uid, vap->va_uid);
 296                 else
 297                         hammer2_guid_to_uuid(&nip->ip_data.uid, xuid);
 298
 299                 if (vap->va_vaflags & VA_GID_UUID_VALID)
 300                         nip->ip_data.gid = vap->va_gid_uuid;
 301                 else if (vap->va_gid != (gid_t)VNOVAL)
 302                         hammer2_guid_to_uuid(&nip->ip_data.gid, vap->va_gid);
 303                 else if (dip)
 304                         nip->ip_data.gid = dip->ip_data.gid;
 305         }
 306
 307         /*
 308          * Regular files and softlinks allow a small amount of data to be
 309          * directly embedded in the inode.  This flag will be cleared if
 310          * the size is extended past the embedded limit.
 311          */
 312         if (nip->ip_data.type == HAMMER2_OBJTYPE_REGFILE ||
 313             nip->ip_data.type == HAMMER2_OBJTYPE_SOFTLINK) {
 314                 nip->ip_data.op_flags |= HAMMER2_OPFLAG_DIRECTDATA;
 315         }
 316
 317         KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
 318         bcopy(name, nip->ip_data.filename, name_len);
 319         nip->ip_data.name_key = lhc;
 320         nip->ip_data.name_len = name_len;
 321
 322         return (0);
 323 }
 324
 325 /*
 326  * Duplicate the specified existing inode in the specified target directory.
 327  * If name is NULL the inode is duplicated as a hidden directory entry.
 328  *
 329  * Returns the new inode.  The old inode is left alone.
 330  *
 331  * XXX name needs to be NULL for now.
 332  */
 333 int
 334 hammer2_inode_duplicate(hammer2_inode_t *dip, hammer2_inode_t *oip,
 335                         hammer2_inode_t **nipp,
 336                         const uint8_t *name, size_t name_len)
 337 {
 338         hammer2_mount_t *hmp = dip->hmp;
 339         hammer2_inode_t *nip;
 340         hammer2_chain_t *parent;
 341         hammer2_chain_t *chain;
 342         hammer2_key_t lhc;
 343         int error;
 344
 345         if (name) {
 346                 lhc = hammer2_dirhash(name, name_len);
 347         } else {
 348                 lhc = oip->ip_data.inum;
 349                 KKASSERT((lhc & HAMMER2_DIRHASH_VISIBLE) == 0);
 350         }
 351
 352         /*
 353          * Locate the inode or indirect block to create the new
 354          * entry in.  At the same time check for key collisions
 355          * and iterate until we don't get one.
 356          */
 357         nip = NULL;
 358         parent = &dip->chain;
 359         hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 360
 361         error = 0;
 362         while (error == 0) {
 363                 chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
 364                 if (chain == NULL)
 365                         break;
 366                 /* XXX bcmp name if not NULL */
 367                 if ((lhc & HAMMER2_DIRHASH_LOMASK) == HAMMER2_DIRHASH_LOMASK)
 368                         error = ENOSPC;
 369                 if ((lhc & HAMMER2_DIRHASH_VISIBLE) == 0) /* shouldn't happen */
 370                         error = ENOSPC;
 371                 hammer2_chain_unlock(hmp, chain);
 372                 chain = NULL;
 373                 ++lhc;
 374         }
 375
 376         /*
 377          * Create entry in common parent directory.
 378          */
 379         if (error == 0) {
 380                 chain = hammer2_chain_create(hmp, parent, NULL, lhc, 0,
 381                                              HAMMER2_BREF_TYPE_INODE /* n/a */,
 382                                              HAMMER2_INODE_BYTES);   /* n/a */
 383                 if (chain == NULL)
 384                         error = EIO;
 385         }
 386         hammer2_chain_unlock(hmp, parent);
 387
 388         /*
 389          * Handle the error case
 390          */
 391         if (error) {
 392                 KKASSERT(chain == NULL);
 393                 return (error);
 394         }
 395
 396         /*
 397          * XXX This is currently a horrible hack.  Well, if we wanted to
 398          *     duplicate a file, i.e. as in a snapshot, we definitely
 399          *     would have to flush it first.
 400          *
 401          *     For hardlink target generation we can theoretically move any
 402          *     active chain structures without flushing, but that gets really
 403          *     iffy for code which follows chain->parent and ip->pip links.
 404          *
 405          * XXX only works with files.  Duplicating a directory hierarchy
 406          *     requires a flush but doesn't deal with races post-flush.
 407          *     Well, it would work I guess, but you might catch some files
 408          *     mid-operation.
 409          *
 410          * We cannot leave oip with any in-memory chains because (for a
 411          * hardlink), oip will become a OBJTYPE_HARDLINK which is just a
 412          * pointer to the real hardlink's inum and can't have any sub-chains.
 413          */
 414         hammer2_inode_lock_ex(oip);
 415         hammer2_chain_flush(hmp, &oip->chain, 0);
 416         hammer2_inode_unlock_ex(oip);
 417         KKASSERT(SPLAY_EMPTY(&oip->chain.shead));
 418
 419         nip = chain->u.ip;
 420         hammer2_chain_modify(hmp, chain, 0);
 421         nip->ip_data = oip->ip_data;    /* sync media data after flush */
 422
 423         if (name) {
 424                 /*
 425                  * Directory entries are inodes so if the name has changed
 426                  * we have to update the inode.
 427                  */
 428                 KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
 429                 bcopy(name, nip->ip_data.filename, name_len);
 430                 nip->ip_data.name_key = lhc;
 431                 nip->ip_data.name_len = name_len;
 432         } else {
 433                 /*
 434                  * Directory entries are inodes but this is a hidden hardlink
 435                  * target.  The name isn't used but to ease debugging give it
 436                  * a name after its inode number.
 437                  */
 438                 ksnprintf(nip->ip_data.filename, sizeof(nip->ip_data.filename),
 439                           "0x%016jx", (intmax_t)nip->ip_data.inum);
 440                 nip->ip_data.name_len = strlen(nip->ip_data.filename);
 441                 nip->ip_data.name_key = lhc;
 442         }
 443         *nipp = nip;
 444
 445         return (0);
 446 }
 447
 448
 449 /*
 450  * Connect inode (oip) to the specified directory using the specified name.
 451  * (oip) must be locked.
 452  *
 453  * If (oip) is not currently connected we simply connect it up.
 454  *
 455  * If (oip) is already connected we create a OBJTYPE_HARDLINK entry which
 456  * points to (oip)'s inode number.  (oip) is expected to be the terminus of
 457  * the hardlink sitting as a hidden file in a common parent directory
 458  * in this situation (thus the lock order is correct).
 459  */
 460 int
 461 hammer2_inode_connect(hammer2_inode_t *dip, hammer2_inode_t *oip,
 462                       const uint8_t *name, size_t name_len)
 463 {
 464         hammer2_mount_t *hmp = dip->hmp;
 465         hammer2_chain_t *chain;
 466         hammer2_chain_t *parent;
 467         hammer2_inode_t *nip;
 468         hammer2_key_t lhc;
 469         int error;
 470         int hlink;
 471
 472         lhc = hammer2_dirhash(name, name_len);
 473         hlink = (oip->chain.parent != NULL);
 474
 475         /*
 476          * In fake mode flush oip so we can just snapshot it downbelow.
 477          */
 478         if (hlink && hammer2_hardlink_enable < 0)
 479                 hammer2_chain_flush(hmp, &oip->chain, 0);
 480
 481         /*
 482          * Locate the inode or indirect block to create the new
 483          * entry in.  At the same time check for key collisions
 484          * and iterate until we don't get one.
 485          */
 486         parent = &dip->chain;
 487         hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 488
 489         error = 0;
 490         while (error == 0) {
 491                 chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
 492                 if (chain == NULL)
 493                         break;
 494                 if ((lhc & HAMMER2_DIRHASH_LOMASK) == HAMMER2_DIRHASH_LOMASK)
 495                         error = ENOSPC;
 496                 hammer2_chain_unlock(hmp, chain);
 497                 chain = NULL;
 498                 ++lhc;
 499         }
 500
 501         /*
 502          * Passing a non-NULL chain to hammer2_chain_create() reconnects the
 503          * existing chain instead of creating a new one.  The chain's bref
 504          * will be properly updated.
 505          */
 506         if (error == 0) {
 507                 if (hlink) {
 508                         chain = hammer2_chain_create(hmp, parent,
 509                                                      NULL, lhc, 0,
 510                                                      HAMMER2_BREF_TYPE_INODE,
 511                                                      HAMMER2_INODE_BYTES);
 512                 } else {
 513                         chain = hammer2_chain_create(hmp, parent,
 514                                                      &oip->chain, lhc, 0,
 515                                                      HAMMER2_BREF_TYPE_INODE,
 516                                                      HAMMER2_INODE_BYTES);
 517                         if (chain)
 518                                 KKASSERT(chain == &oip->chain);
 519                 }
 520                 if (chain == NULL)
 521                         error = EIO;
 522         }
 523         hammer2_chain_unlock(hmp, parent);
 524
 525         /*
 526          * Handle the error case
 527          */
 528         if (error) {
 529                 KKASSERT(chain == NULL);
 530                 return (error);
 531         }
 532
 533         /*
 534          * Directory entries are inodes so if the name has changed we have
 535          * to update the inode.
 536          *
 537          * When creating an OBJTYPE_HARDLINK entry remember to unlock the
 538          * chain, the caller will access the hardlink via the actual hardlink
 539          * target file and not the hardlink pointer entry.
 540          */
 541         if (hlink && hammer2_hardlink_enable >= 0) {
 542                 /*
 543                  * Create the HARDLINK pointer.  oip represents the hardlink
 544                  * target in this situation.
 545                  */
 546                 nip = chain->u.ip;
 547                 hammer2_chain_modify(hmp, chain, 0);
 548                 KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
 549                 bcopy(name, nip->ip_data.filename, name_len);
 550                 nip->ip_data.name_key = lhc;
 551                 nip->ip_data.name_len = name_len;
 552                 nip->ip_data.target_type = oip->ip_data.type;
 553                 nip->ip_data.type = HAMMER2_OBJTYPE_HARDLINK;
 554                 nip->ip_data.inum = oip->ip_data.inum;
 555                 nip->ip_data.nlinks = 1;
 556                 kprintf("created hardlink %*.*s\n",
 557                         (int)name_len, (int)name_len, name);
 558                 hammer2_chain_unlock(hmp, chain);
 559         } else if (hlink && hammer2_hardlink_enable < 0) {
 560                 /*
 561                  * Create a snapshot (hardlink fake mode for debugging).
 562                  */
 563                 nip = chain->u.ip;
 564                 nip->ip_data = oip->ip_data;
 565                 hammer2_chain_modify(hmp, chain, 0);
 566                 KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
 567                 bcopy(name, nip->ip_data.filename, name_len);
 568                 nip->ip_data.name_key = lhc;
 569                 nip->ip_data.name_len = name_len;
 570                 kprintf("created fake hardlink %*.*s\n",
 571                         (int)name_len, (int)name_len, name);
 572                 hammer2_chain_unlock(hmp, chain);
 573         } else {
 574                 /*
 575                  * Normally disconnected inode (e.g. during a rename) that
 576                  * was reconnected.  We must fixup the name stored in
 577                  * oip.
 578                  *
 579                  * We are using oip as chain, already locked by caller,
 580                  * do not unlock it.
 581                  */
 582                 hammer2_chain_modify(hmp, chain, 0);
 583                 if (oip->ip_data.name_len != name_len ||
 584                     bcmp(oip->ip_data.filename, name, name_len) != 0) {
 585                         KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
 586                         bcopy(name, oip->ip_data.filename, name_len);
 587                         oip->ip_data.name_key = lhc;
 588                         oip->ip_data.name_len = name_len;
 589                 }
 590                 oip->ip_data.nlinks = 1;
 591         }
 592
 593         return (0);
 594 }
 595
 596 /*
 597  * Unlink the file from the specified directory inode.  The directory inode
 598  * does not need to be locked.
 599  *
 600  * isdir determines whether a directory/non-directory check should be made.
 601  * No check is made if isdir is set to -1.
 602  */
 603 int
 604 hammer2_unlink_file(hammer2_inode_t *dip,
 605                     const uint8_t *name, size_t name_len,
 606                     int isdir, hammer2_inode_t *retain_ip)
 607 {
 608         hammer2_mount_t *hmp;
 609         hammer2_chain_t *parent;
 610         hammer2_chain_t *chain;
 611         hammer2_chain_t *dparent;
 612         hammer2_chain_t *dchain;
 613         hammer2_key_t lhc;
 614         hammer2_inode_t *ip;
 615         hammer2_inode_t *oip;
 616         int error;
 617         uint8_t type;
 618
 619         error = 0;
 620         oip = NULL;
 621         hmp = dip->hmp;
 622         lhc = hammer2_dirhash(name, name_len);
 623
 624         /*
 625          * Search for the filename in the directory
 626          */
 627         parent = &dip->chain;
 628         hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 629         chain = hammer2_chain_lookup(hmp, &parent,
 630                                      lhc, lhc + HAMMER2_DIRHASH_LOMASK,
 631                                      0);
 632         while (chain) {
 633                 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE &&
 634                     chain->u.ip &&
 635                     name_len == chain->data->ipdata.name_len &&
 636                     bcmp(name, chain->data->ipdata.filename, name_len) == 0) {
 637                         break;
 638                 }
 639                 chain = hammer2_chain_next(hmp, &parent, chain,
 640                                            lhc, lhc + HAMMER2_DIRHASH_LOMASK,
 641                                            0);
 642         }
 643
 644         /*
 645          * Not found or wrong type (isdir < 0 disables the type check).
 646          */
 647         if (chain == NULL) {
 648                 hammer2_chain_unlock(hmp, parent);
 649                 return ENOENT;
 650         }
 651         if ((type = chain->data->ipdata.type) == HAMMER2_OBJTYPE_HARDLINK)
 652                 type = chain->data->ipdata.target_type;
 653
 654         if (type == HAMMER2_OBJTYPE_DIRECTORY && isdir == 0) {
 655                 error = ENOTDIR;
 656                 goto done;
 657         }
 658         if (type != HAMMER2_OBJTYPE_DIRECTORY && isdir == 1) {
 659                 error = EISDIR;
 660                 goto done;
 661         }
 662
 663         /*
 664          * Hardlink must be resolved.  We can't hold parent locked while we
 665          * do this or we could deadlock.
 666          */
 667         if (chain->data->ipdata.type == HAMMER2_OBJTYPE_HARDLINK) {
 668                 hammer2_chain_unlock(hmp, parent);
 669                 parent = NULL;
 670                 error = hammer2_hardlink_find(dip, &chain, &oip);
 671         }
 672
 673         /*
 674          * If this is a directory the directory must be empty.  However, if
 675          * isdir < 0 we are doing a rename and the directory does not have
 676          * to be empty.
 677          *
 678          * NOTE: We check the full key range here which covers both visible
 679          *       and invisible entries.  Theoretically there should be no
 680          *       invisible (hardlink target) entries if there are no visible
 681          *       entries.
 682          */
 683         if (type == HAMMER2_OBJTYPE_DIRECTORY && isdir >= 0) {
 684                 dparent = chain;
 685                 hammer2_chain_lock(hmp, dparent, HAMMER2_RESOLVE_ALWAYS);
 686                 dchain = hammer2_chain_lookup(hmp, &dparent,
 687                                               0, (hammer2_key_t)-1,
 688                                               HAMMER2_LOOKUP_NODATA);
 689                 if (dchain) {
 690                         hammer2_chain_unlock(hmp, dchain);
 691                         hammer2_chain_unlock(hmp, dparent);
 692                         error = ENOTEMPTY;
 693                         goto done;
 694                 }
 695                 hammer2_chain_unlock(hmp, dparent);
 696                 dparent = NULL;
 697                 /* dchain NULL */
 698         }
 699
 700         /*
 701          * Ok, we can now unlink the chain.  We always decrement nlinks even
 702          * if the entry can be deleted in case someone has the file open and
 703          * does an fstat().
 704          *
 705          * The chain itself will no longer be in the on-media topology but
 706          * can still be flushed to the media (e.g. if an open descriptor
 707          * remains).  When the last vnode/ip ref goes away the chain will
 708          * be marked unmodified, avoiding any further (now unnecesary) I/O.
 709          */
 710         if (oip) {
 711                 /*
 712                  * If this was a hardlink we first delete the hardlink
 713                  * pointer entry.
 714                  */
 715                 parent = oip->chain.parent;
 716                 hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 717                 hammer2_chain_lock(hmp, &oip->chain, HAMMER2_RESOLVE_ALWAYS);
 718                 hammer2_chain_delete(hmp, parent, &oip->chain,
 719                                     (retain_ip == oip));
 720                 hammer2_chain_unlock(hmp, &oip->chain);
 721                 hammer2_chain_unlock(hmp, parent);
 722                 parent = NULL;
 723
 724                 /*
 725                  * Then decrement nlinks on hardlink target.
 726                  */
 727                 ip = chain->u.ip;
 728                 if (ip->ip_data.nlinks == 1) {
 729                         dparent = chain->parent;
 730                         hammer2_chain_ref(hmp, chain);
 731                         hammer2_chain_unlock(hmp, chain);
 732                         hammer2_chain_lock(hmp, dparent,
 733                                            HAMMER2_RESOLVE_ALWAYS);
 734                         hammer2_chain_lock(hmp, chain, HAMMER2_RESOLVE_ALWAYS);
 735                         hammer2_chain_drop(hmp, chain);
 736                         hammer2_chain_modify(hmp, chain, 0);
 737                         --ip->ip_data.nlinks;
 738                         hammer2_chain_delete(hmp, dparent, chain, 0);
 739                         hammer2_chain_unlock(hmp, dparent);
 740                 } else {
 741                         hammer2_chain_modify(hmp, chain, 0);
 742                         --ip->ip_data.nlinks;
 743                 }
 744         } else {
 745                 /*
 746                  * Otherwise this was not a hardlink and we can just
 747                  * remove the entry and decrement nlinks.
 748                  */
 749                 ip = chain->u.ip;
 750                 hammer2_chain_modify(hmp, chain, 0);
 751                 --ip->ip_data.nlinks;
 752                 hammer2_chain_delete(hmp, parent, chain,
 753                                      (retain_ip == ip));
 754         }
 755
 756         error = 0;
 757
 758 done:
 759         if (chain)
 760                 hammer2_chain_unlock(hmp, chain);
 761         if (parent)
 762                 hammer2_chain_unlock(hmp, parent);
 763         if (oip)
 764                 hammer2_chain_drop(oip->hmp, &oip->chain);
 765
 766         return error;
 767 }
 768
 769 /*
 770  * Calculate the allocation size for the file fragment straddling EOF
 771  */
 772 int
 773 hammer2_inode_calc_alloc(hammer2_key_t filesize)
 774 {
 775         int frag = (int)filesize & HAMMER2_PBUFMASK;
 776         int radix;
 777
 778         if (frag == 0)
 779                 return(0);
 780         for (radix = HAMMER2_MINALLOCRADIX; frag > (1 << radix); ++radix)
 781                 ;
 782         return (radix);
 783 }
 784
 785 void
 786 hammer2_inode_lock_nlinks(hammer2_inode_t *ip)
 787 {
 788         hammer2_chain_ref(ip->hmp, &ip->chain);
 789 }
 790
 791 void
 792 hammer2_inode_unlock_nlinks(hammer2_inode_t *ip)
 793 {
 794         hammer2_chain_drop(ip->hmp, &ip->chain);
 795 }
 796
 797 /*
 798  * Consolidate for hard link creation.  This moves the specified terminal
 799  * hardlink inode to a directory common to its current directory and tdip
 800  * if necessary, replacing *ipp with the new inode chain element and
 801  * modifying the original inode chain element to OBJTYPE_HARDLINK.
 802  *
 803  * If the original inode chain element was a prior incarnation of a hidden
 804  * inode it can simply be deleted instead of converted.
 805  *
 806  * (*ipp)'s nlinks field is locked on entry and the new (*ipp)'s nlinks
 807  * field will be locked on return (with the original's unlocked).
 808  *
 809  * The link count is bumped if requested.
 810  */
 811 int
 812 hammer2_hardlink_consolidate(hammer2_inode_t **ipp, hammer2_inode_t *tdip)
 813 {
 814         hammer2_mount_t *hmp;
 815         hammer2_inode_t *oip = *ipp;
 816         hammer2_inode_t *nip = NULL;
 817         hammer2_inode_t *fdip;
 818         hammer2_chain_t *parent;
 819         int error;
 820
 821         hmp = tdip->hmp;
 822
 823         if (hammer2_hardlink_enable < 0)
 824                 return (0);
 825         if (hammer2_hardlink_enable == 0)
 826                 return (ENOTSUP);
 827
 828         /*
 829          * Find the common parent directory
 830          */
 831         fdip = oip->pip;
 832         while (fdip->depth > tdip->depth) {
 833                 fdip = fdip->pip;
 834                 KKASSERT(fdip != NULL);
 835         }
 836         while (tdip->depth > fdip->depth) {
 837                 tdip = tdip->pip;
 838                 KKASSERT(tdip != NULL);
 839         }
 840         while (fdip != tdip) {
 841                 fdip = fdip->pip;
 842                 tdip = tdip->pip;
 843                 KKASSERT(fdip != NULL);
 844                 KKASSERT(tdip != NULL);
 845         }
 846
 847         /*
 848          * Nothing to do (except bump the link count) if the hardlink has
 849          * already been consolidated in the correct place.
 850          */
 851         if (oip->pip == fdip &&
 852             (oip->ip_data.name_key & HAMMER2_DIRHASH_VISIBLE) == 0) {
 853                 kprintf("hardlink already consolidated correctly\n");
 854                 nip = oip;
 855                 hammer2_inode_lock_ex(nip);
 856                 hammer2_chain_modify(hmp, &nip->chain, 0);
 857                 ++nip->ip_data.nlinks;
 858                 hammer2_inode_unlock_ex(nip);
 859                 return (0);
 860         }
 861
 862         /*
 863          * Create a hidden inode directory entry in the parent, copying
 864          * (*oip)'s state.  Then replace oip with OBJTYPE_HARDLINK.
 865          *
 866          * The duplication function will either flush or move any chains
 867          * under oip to the new hardlink target inode, retiring all chains
 868          * related to oip before returning.  XXX vp->ip races.
 869          */
 870         error = hammer2_inode_duplicate(fdip, oip, &nip, NULL, 0);
 871         if (error == 0) {
 872                 /*
 873                  * Bump nlinks on duplicated hidden inode.
 874                  */
 875                 kprintf("hardlink consolidation success in parent dir %s\n",
 876                         fdip->ip_data.filename);
 877                 hammer2_inode_lock_nlinks(nip);
 878                 hammer2_inode_unlock_nlinks(oip);
 879                 hammer2_chain_modify(hmp, &nip->chain, 0);
 880                 ++nip->ip_data.nlinks;
 881                 hammer2_inode_unlock_ex(nip);
 882
 883                 if (oip->ip_data.name_key & HAMMER2_DIRHASH_VISIBLE) {
 884                         /*
 885                          * Replace the old inode with an OBJTYPE_HARDLINK
 886                          * pointer.
 887                          */
 888                         hammer2_inode_lock_ex(oip);
 889                         hammer2_chain_modify(hmp, &oip->chain, 0);
 890                         oip->ip_data.target_type = oip->ip_data.type;
 891                         oip->ip_data.type = HAMMER2_OBJTYPE_HARDLINK;
 892                         oip->ip_data.uflags = 0;
 893                         oip->ip_data.rmajor = 0;
 894                         oip->ip_data.rminor = 0;
 895                         oip->ip_data.ctime = 0;
 896                         oip->ip_data.mtime = 0;
 897                         oip->ip_data.atime = 0;
 898                         oip->ip_data.btime = 0;
 899                         bzero(&oip->ip_data.uid, sizeof(oip->ip_data.uid));
 900                         bzero(&oip->ip_data.gid, sizeof(oip->ip_data.gid));
 901                         oip->ip_data.op_flags = HAMMER2_OPFLAG_DIRECTDATA;
 902                         oip->ip_data.cap_flags = 0;
 903                         oip->ip_data.mode = 0;
 904                         oip->ip_data.size = 0;
 905                         oip->ip_data.nlinks = 1;
 906                         oip->ip_data.iparent = 0;       /* XXX */
 907                         oip->ip_data.pfs_type = 0;
 908                         oip->ip_data.pfs_inum = 0;
 909                         bzero(&oip->ip_data.pfs_id,
 910                               sizeof(oip->ip_data.pfs_id));
 911                         bzero(&oip->ip_data.pfs_fsid,
 912                               sizeof(oip->ip_data.pfs_fsid));
 913                         oip->ip_data.data_quota = 0;
 914                         oip->ip_data.data_count = 0;
 915                         oip->ip_data.inode_quota = 0;
 916                         oip->ip_data.inode_count = 0;
 917                         oip->ip_data.attr_tid = 0;
 918                         oip->ip_data.dirent_tid = 0;
 919                         bzero(&oip->ip_data.u, sizeof(oip->ip_data.u));
 920                         /* XXX transaction ids */
 921
 922                         hammer2_inode_unlock_ex(oip);
 923                 } else {
 924                         /*
 925                          * The old inode was a hardlink target, which we
 926                          * have now moved.  We must delete it so the new
 927                          * hardlink target at a higher directory level
 928                          * becomes the only hardlink target for this inode.
 929                          */
 930                         kprintf("DELETE INVISIBLE\n");
 931                         parent = oip->chain.parent;
 932                         hammer2_chain_lock(hmp, parent,
 933                                            HAMMER2_RESOLVE_ALWAYS);
 934                         hammer2_chain_lock(hmp, &oip->chain,
 935                                            HAMMER2_RESOLVE_ALWAYS);
 936                         hammer2_chain_delete(hmp, parent, &oip->chain, 0);
 937                         hammer2_chain_unlock(hmp, &oip->chain);
 938                         hammer2_chain_unlock(hmp, parent);
 939                 }
 940                 *ipp = nip;
 941         } else {
 942                 KKASSERT(nip == NULL);
 943         }
 944
 945         return (error);
 946 }
 947
 948 /*
 949  * If (*ipp) is non-NULL it points to the forward OBJTYPE_HARDLINK inode while
 950  * (*chainp) points to the resolved (hidden hardlink target) inode.  In this
 951  * situation when nlinks is 1 we wish to deconsolidate the hardlink, moving
 952  * it back to the directory that now represents the only remaining link.
 953  */
 954 int
 955 hammer2_hardlink_deconsolidate(hammer2_inode_t *dip, hammer2_chain_t **chainp,
 956                                hammer2_inode_t **ipp)
 957 {
 958         if (*ipp == NULL)
 959                 return (0);
 960         /* XXX */
 961         return (0);
 962 }
 963
 964 /*
 965  * When presented with a (*chainp) representing an inode of type
 966  * OBJTYPE_HARDLINK this code will save the original inode (with a ref)
 967  * in (*ipp), and then locate the hidden hardlink target in (dip) or
 968  * any parent directory above (dip).  The locked (*chainp) is replaced
 969  * with a new locked (*chainp) representing the hardlink target.
 970  */
 971 int
 972 hammer2_hardlink_find(hammer2_inode_t *dip, hammer2_chain_t **chainp,
 973                       hammer2_inode_t **ipp)
 974 {
 975         hammer2_mount_t *hmp = dip->hmp;
 976         hammer2_chain_t *chain = *chainp;
 977         hammer2_chain_t *parent;
 978         hammer2_inode_t *pip;
 979         hammer2_key_t lhc;
 980
 981         *ipp = chain->u.ip;
 982         hammer2_inode_ref(chain->u.ip);
 983         lhc = chain->u.ip->ip_data.inum;
 984
 985         hammer2_inode_unlock_ex(chain->u.ip);
 986         pip = chain->u.ip->pip;
 987
 988         chain = NULL;
 989         while (pip) {
 990                 parent = &pip->chain;
 991                 KKASSERT(parent->bref.type == HAMMER2_BREF_TYPE_INODE);
 992
 993                 hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 994                 chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
 995                 hammer2_chain_unlock(hmp, parent);
 996                 if (chain)
 997                         break;
 998                 pip = pip->pip;
 999         }
1000         *chainp = chain;
1001         if (chain) {
1002                 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
1003                 /* already locked */
1004                 return (0);
1005         } else {
1006                 return (EIO);
1007         }
1008 }