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 int
 332 hammer2_inode_duplicate(hammer2_inode_t *dip, hammer2_inode_t *oip,
 333                         hammer2_inode_t **nipp,
 334                         const uint8_t *name, size_t name_len)
 335 {
 336         hammer2_mount_t *hmp = dip->hmp;
 337         hammer2_inode_t *nip;
 338         hammer2_chain_t *parent;
 339         hammer2_chain_t *chain;
 340         hammer2_chain_t *scan;
 341         hammer2_key_t lhc;
 342         int error;
 343
 344         if (name) {
 345                 lhc = hammer2_dirhash(name, name_len);
 346         } else {
 347                 lhc = oip->ip_data.inum;
 348                 KKASSERT((lhc & HAMMER2_DIRHASH_VISIBLE) == 0);
 349         }
 350
 351         /*
 352          * Locate the inode or indirect block to create the new
 353          * entry in.  At the same time check for key collisions
 354          * and iterate until we don't get one.
 355          */
 356         nip = NULL;
 357         parent = &dip->chain;
 358         hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 359
 360         error = 0;
 361         while (error == 0) {
 362                 chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
 363                 if (chain == NULL)
 364                         break;
 365                 if ((lhc & HAMMER2_DIRHASH_LOMASK) == HAMMER2_DIRHASH_LOMASK)
 366                         error = ENOSPC;
 367                 hammer2_chain_unlock(hmp, chain);
 368                 chain = NULL;
 369                 ++lhc;
 370         }
 371
 372         /*
 373          * Passing a non-NULL chain to hammer2_chain_create() reconnects the
 374          * existing chain instead of creating a new one.  The chain's bref
 375          * will be properly updated.
 376          */
 377         if (error == 0) {
 378                 chain = hammer2_chain_create(hmp, parent, NULL, lhc, 0,
 379                                              HAMMER2_BREF_TYPE_INODE /* n/a */,
 380                                              HAMMER2_INODE_BYTES);   /* n/a */
 381                 if (chain == NULL)
 382                         error = EIO;
 383         }
 384         hammer2_chain_unlock(hmp, parent);
 385
 386         /*
 387          * Handle the error case
 388          */
 389         if (error) {
 390                 KKASSERT(chain == NULL);
 391                 return (error);
 392         }
 393         nip = chain->u.ip;
 394         hammer2_chain_modify(hmp, chain, 0);
 395         nip->ip_data = oip->ip_data;
 396
 397         /*
 398          * XXX This is currently a horrible hack.  Well, if we wanted to
 399          *     duplicate a file, i.e. as in a snapshot, we definitely
 400          *     would have to flush it first.
 401          *
 402          *     For hardlink target generation we can theoretically move any
 403          *     active chain structures without flushing, but that gets really
 404          *     iffy for code which follows chain->parent and ip->pip links.
 405          *
 406          * XXX only works with files.  Duplicating a directory hierarchy
 407          *     requires a flush but doesn't deal with races post-flush.
 408          *     Well, it would work I guess, but you might catch some files
 409          *     mid-operation.
 410          *
 411          * We cannot leave oip with any in-memory chains because (for a
 412          * hardlink), oip will become a OBJTYPE_HARDLINK which is just a
 413          * pointer to the real hardlink's inum and can't have any sub-chains.
 414          */
 415         hammer2_inode_lock_ex(oip);
 416         hammer2_chain_flush(hmp, &oip->chain, 0);
 417         hammer2_inode_unlock_ex(oip);
 418         KKASSERT(SPLAY_EMPTY(&oip->chain.shead));
 419
 420         if (name) {
 421                 /*
 422                  * Directory entries are inodes so if the name has changed
 423                  * we have to update the inode.
 424                  */
 425                 KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
 426                 bcopy(name, nip->ip_data.filename, name_len);
 427                 nip->ip_data.name_key = lhc;
 428                 nip->ip_data.name_len = name_len;
 429         } else {
 430                 /*
 431                  * Directory entries are inodes but this is a hidden hardlink
 432                  * target.  The name isn't used but to ease debugging give it
 433                  * a name after its inode number.
 434                  */
 435                 ksnprintf(nip->ip_data.filename, sizeof(nip->ip_data.filename),
 436                           "0x%016jx", (intmax_t)nip->ip_data.inum);
 437                 nip->ip_data.name_len = strlen(nip->ip_data.filename);
 438                 nip->ip_data.name_key = lhc;
 439         }
 440         *nipp = nip;
 441
 442         return (0);
 443 }
 444
 445
 446 /*
 447  * Connect inode (oip) to the specified directory using the specified name.
 448  * (oip) must be locked.
 449  *
 450  * If (oip) is not currently connected we simply connect it up.
 451  *
 452  * If (oip) is already connected we create a OBJTYPE_HARDLINK entry which
 453  * points to (oip)'s inode number.  (oip) is expected to be the terminus of
 454  * the hardlink sitting as a hidden file in a common parent directory
 455  * in this situation (thus the lock order is correct).
 456  */
 457 int
 458 hammer2_inode_connect(hammer2_inode_t *dip, hammer2_inode_t *oip,
 459                       const uint8_t *name, size_t name_len)
 460 {
 461         hammer2_mount_t *hmp = dip->hmp;
 462         hammer2_chain_t *chain;
 463         hammer2_chain_t *parent;
 464         hammer2_inode_t *nip;
 465         hammer2_key_t lhc;
 466         int error;
 467         int hlink;
 468
 469         lhc = hammer2_dirhash(name, name_len);
 470         hlink = ((oip->chain.flags & HAMMER2_CHAIN_DELETED) == 0);
 471
 472         /*
 473          * Locate the inode or indirect block to create the new
 474          * entry in.  At the same time check for key collisions
 475          * and iterate until we don't get one.
 476          */
 477         parent = &dip->chain;
 478         hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 479
 480         error = 0;
 481         while (error == 0) {
 482                 chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
 483                 if (chain == NULL)
 484                         break;
 485                 if ((lhc & HAMMER2_DIRHASH_LOMASK) == HAMMER2_DIRHASH_LOMASK)
 486                         error = ENOSPC;
 487                 hammer2_chain_unlock(hmp, chain);
 488                 chain = NULL;
 489                 ++lhc;
 490         }
 491
 492         /*
 493          * Passing a non-NULL chain to hammer2_chain_create() reconnects the
 494          * existing chain instead of creating a new one.  The chain's bref
 495          * will be properly updated.
 496          */
 497         if (error == 0) {
 498                 if (hlink) {
 499                         chain = hammer2_chain_create(hmp, parent,
 500                                                      NULL, lhc, 0,
 501                                                      HAMMER2_BREF_TYPE_INODE,
 502                                                      HAMMER2_INODE_BYTES);
 503                 } else {
 504                         chain = hammer2_chain_create(hmp, parent,
 505                                                      &oip->chain, lhc, 0,
 506                                                      HAMMER2_BREF_TYPE_INODE,
 507                                                      HAMMER2_INODE_BYTES);
 508                         if (chain)
 509                                 KKASSERT(chain == &oip->chain);
 510                 }
 511                 if (chain == NULL)
 512                         error = EIO;
 513         }
 514         hammer2_chain_unlock(hmp, parent);
 515
 516         /*
 517          * Handle the error case
 518          */
 519         if (error) {
 520                 KKASSERT(chain == NULL);
 521                 return (error);
 522         }
 523
 524         /*
 525          * Directory entries are inodes so if the name has changed we have
 526          * to update the inode.
 527          *
 528          * When creating an OBJTYPE_HARDLINK entry remember to unlock the
 529          * chain, the caller will access the hardlink via the actual hardlink
 530          * target file and not the hardlink pointer entry.
 531          */
 532         if (hlink) {
 533                 /*
 534                  * Create the HARDLINK pointer.  oip represents the hardlink
 535                  * target in this situation.
 536                  */
 537                 nip = chain->u.ip;
 538                 hammer2_chain_modify(hmp, chain, 0);
 539                 KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
 540                 bcopy(name, nip->ip_data.filename, name_len);
 541                 nip->ip_data.name_key = lhc;
 542                 nip->ip_data.name_len = name_len;
 543                 nip->ip_data.target_type = oip->ip_data.type;
 544                 nip->ip_data.type = HAMMER2_OBJTYPE_HARDLINK;
 545                 nip->ip_data.inum = oip->ip_data.inum;
 546                 nip->ip_data.nlinks = 1;
 547                 kprintf("created hardlink %*.*s\n",
 548                         (int)name_len, (int)name_len, name);
 549                 hammer2_chain_unlock(hmp, chain);
 550         } else {
 551                 /*
 552                  * The name may have changed on reconnect, adjust oip.
 553                  *
 554                  * We are using oip as chain, already locked by caller,
 555                  * do not unlock it.
 556                  */
 557                 hammer2_chain_modify(hmp, chain, 0);
 558                 if (oip->ip_data.name_len != name_len ||
 559                     bcmp(oip->ip_data.filename, name, name_len) != 0) {
 560                         KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
 561                         bcopy(name, oip->ip_data.filename, name_len);
 562                         oip->ip_data.name_key = lhc;
 563                         oip->ip_data.name_len = name_len;
 564                 }
 565                 oip->ip_data.nlinks = 1;
 566         }
 567
 568         return (0);
 569 }
 570
 571 /*
 572  * Unlink the file from the specified directory inode.  The directory inode
 573  * does not need to be locked.
 574  *
 575  * isdir determines whether a directory/non-directory check should be made.
 576  * No check is made if isdir is set to -1.
 577  */
 578 int
 579 hammer2_unlink_file(hammer2_inode_t *dip,
 580                     const uint8_t *name, size_t name_len, int isdir)
 581 {
 582         hammer2_mount_t *hmp;
 583         hammer2_chain_t *parent;
 584         hammer2_chain_t *chain;
 585         hammer2_chain_t *dparent;
 586         hammer2_chain_t *dchain;
 587         hammer2_key_t lhc;
 588         hammer2_inode_t *ip;
 589         hammer2_inode_t *oip;
 590         int error;
 591         uint8_t type;
 592
 593         error = 0;
 594         oip = NULL;
 595         hmp = dip->hmp;
 596         lhc = hammer2_dirhash(name, name_len);
 597
 598         /*
 599          * Search for the filename in the directory
 600          */
 601         parent = &dip->chain;
 602         hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 603         chain = hammer2_chain_lookup(hmp, &parent,
 604                                      lhc, lhc + HAMMER2_DIRHASH_LOMASK,
 605                                      0);
 606         while (chain) {
 607                 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE &&
 608                     chain->u.ip &&
 609                     name_len == chain->data->ipdata.name_len &&
 610                     bcmp(name, chain->data->ipdata.filename, name_len) == 0) {
 611                         break;
 612                 }
 613                 chain = hammer2_chain_next(hmp, &parent, chain,
 614                                            lhc, lhc + HAMMER2_DIRHASH_LOMASK,
 615                                            0);
 616         }
 617
 618         /*
 619          * Not found or wrong type (isdir < 0 disables the type check).
 620          */
 621         if (chain == NULL) {
 622                 hammer2_chain_unlock(hmp, parent);
 623                 return ENOENT;
 624         }
 625         if ((type = chain->data->ipdata.type) == HAMMER2_OBJTYPE_HARDLINK)
 626                 type = chain->data->ipdata.target_type;
 627
 628         if (type == HAMMER2_OBJTYPE_DIRECTORY && isdir == 0) {
 629                 error = ENOTDIR;
 630                 goto done;
 631         }
 632         if (type != HAMMER2_OBJTYPE_DIRECTORY && isdir == 1) {
 633                 error = EISDIR;
 634                 goto done;
 635         }
 636
 637         /*
 638          * Hardlink must be resolved.  We can't hold parent locked while we
 639          * do this or we could deadlock.
 640          */
 641         if (chain->data->ipdata.type == HAMMER2_OBJTYPE_HARDLINK) {
 642                 hammer2_chain_unlock(hmp, parent);
 643                 parent = NULL;
 644                 error = hammer2_hardlink_find(dip, &chain, &oip);
 645         }
 646
 647         /*
 648          * If this is a directory the directory must be empty.  However, if
 649          * isdir < 0 we are doing a rename and the directory does not have
 650          * to be empty.
 651          */
 652         if (type == HAMMER2_OBJTYPE_DIRECTORY && isdir >= 0) {
 653                 dparent = chain;
 654                 hammer2_chain_lock(hmp, dparent, HAMMER2_RESOLVE_ALWAYS);
 655                 dchain = hammer2_chain_lookup(hmp, &dparent,
 656                                               0, (hammer2_key_t)-1,
 657                                               HAMMER2_LOOKUP_NODATA);
 658                 if (dchain) {
 659                         hammer2_chain_unlock(hmp, dchain);
 660                         hammer2_chain_unlock(hmp, dparent);
 661                         error = ENOTEMPTY;
 662                         goto done;
 663                 }
 664                 hammer2_chain_unlock(hmp, dparent);
 665                 dparent = NULL;
 666                 /* dchain NULL */
 667         }
 668
 669         /*
 670          * Ok, we can now unlink the chain.  We always decrement nlinks even
 671          * if the entry can be deleted in case someone has the file open and
 672          * does an fstat().
 673          *
 674          * The chain itself will no longer have a media reference.  When the
 675          * last vnode/ip ref goes away the chain will be marked unmodified,
 676          * avoiding unnecessary I/O.
 677          */
 678         if (oip) {
 679                 /*
 680                  * If this was a hardlink we first delete the hardlink
 681                  * pointer entry.
 682                  */
 683                 parent = oip->chain.parent;
 684                 hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 685                 hammer2_chain_lock(hmp, &oip->chain, HAMMER2_RESOLVE_ALWAYS);
 686                 hammer2_chain_delete(hmp, parent, &oip->chain);
 687                 hammer2_chain_unlock(hmp, &oip->chain);
 688                 hammer2_chain_unlock(hmp, parent);
 689                 parent = NULL;
 690
 691                 /*
 692                  * Then decrement nlinks on hardlink target.
 693                  */
 694                 ip = chain->u.ip;
 695                 if (ip->ip_data.nlinks == 1) {
 696                         dparent = chain->parent;
 697                         hammer2_chain_ref(hmp, chain);
 698                         hammer2_chain_unlock(hmp, chain);
 699                         hammer2_chain_lock(hmp, dparent,
 700                                            HAMMER2_RESOLVE_ALWAYS);
 701                         hammer2_chain_lock(hmp, chain, HAMMER2_RESOLVE_ALWAYS);
 702                         hammer2_chain_drop(hmp, chain);
 703                         hammer2_chain_modify(hmp, chain, 0);
 704                         --ip->ip_data.nlinks;
 705                         hammer2_chain_delete(hmp, dparent, chain);
 706                         hammer2_chain_unlock(hmp, dparent);
 707                 } else {
 708                         hammer2_chain_modify(hmp, chain, 0);
 709                         --ip->ip_data.nlinks;
 710                 }
 711         } else {
 712                 /*
 713                  * Otherwise this was not a hardlink and we can just
 714                  * remove the entry and decrement nlinks.
 715                  */
 716                 ip = chain->u.ip;
 717                 hammer2_chain_modify(hmp, chain, 0);
 718                 --ip->ip_data.nlinks;
 719                 hammer2_chain_delete(hmp, parent, chain);
 720         }
 721
 722         error = 0;
 723
 724 done:
 725         if (chain)
 726                 hammer2_chain_unlock(hmp, chain);
 727         if (parent)
 728                 hammer2_chain_unlock(hmp, parent);
 729         if (oip)
 730                 hammer2_chain_drop(oip->hmp, &oip->chain);
 731
 732         return error;
 733 }
 734
 735 /*
 736  * Calculate the allocation size for the file fragment straddling EOF
 737  */
 738 int
 739 hammer2_inode_calc_alloc(hammer2_key_t filesize)
 740 {
 741         int frag = (int)filesize & HAMMER2_PBUFMASK;
 742         int radix;
 743
 744         if (frag == 0)
 745                 return(0);
 746         for (radix = HAMMER2_MINALLOCRADIX; frag > (1 << radix); ++radix)
 747                 ;
 748         return (radix);
 749 }
 750
 751 void
 752 hammer2_inode_lock_nlinks(hammer2_inode_t *ip)
 753 {
 754         hammer2_chain_ref(ip->hmp, &ip->chain);
 755 }
 756
 757 void
 758 hammer2_inode_unlock_nlinks(hammer2_inode_t *ip)
 759 {
 760         hammer2_chain_drop(ip->hmp, &ip->chain);
 761 }
 762
 763 /*
 764  * Consolidate for hard link creation.  This moves the specified terminal
 765  * hardlink inode to a directory common to its current directory and tdip
 766  * if necessary, replacing *ipp with the new inode chain element and
 767  * modifying the original inode chain element to OBJTYPE_HARDLINK.
 768  *
 769  * If the original inode chain element was a prior incarnation of a hidden
 770  * inode it can simply be deleted instead of converted.
 771  *
 772  * (*ipp)'s nlinks field is locked on entry and the new (*ipp)'s nlinks
 773  * field will be locked on return (with the original's unlocked).
 774  *
 775  * The link count is bumped if requested.
 776  */
 777 int
 778 hammer2_hardlink_consolidate(hammer2_inode_t **ipp, hammer2_inode_t *tdip)
 779 {
 780         hammer2_mount_t *hmp;
 781         hammer2_inode_t *oip = *ipp;
 782         hammer2_inode_t *nip = NULL;
 783         hammer2_inode_t *fdip;
 784         hammer2_chain_t *parent;
 785         int error;
 786
 787         hmp = tdip->hmp;
 788
 789         if (hammer2_hardlink_enable < 0)
 790                 return (0);
 791         if (hammer2_hardlink_enable == 0)
 792                 return (ENOTSUP);
 793
 794         /*
 795          * Find the common parent directory
 796          */
 797         fdip = oip->pip;
 798         while (fdip->depth > tdip->depth) {
 799                 fdip = fdip->pip;
 800                 KKASSERT(fdip != NULL);
 801         }
 802         while (tdip->depth > fdip->depth) {
 803                 tdip = tdip->pip;
 804                 KKASSERT(tdip != NULL);
 805         }
 806         while (fdip != tdip) {
 807                 fdip = fdip->pip;
 808                 tdip = tdip->pip;
 809                 KKASSERT(fdip != NULL);
 810                 KKASSERT(tdip != NULL);
 811         }
 812
 813         /*
 814          * Nothing to do (except bump the link count) if the hardlink has
 815          * already been consolidated in the correct place.
 816          */
 817         if (oip->pip == fdip &&
 818             (oip->ip_data.name_key & HAMMER2_DIRHASH_VISIBLE) == 0) {
 819                 kprintf("hardlink already consolidated correctly\n");
 820                 nip = oip;
 821                 hammer2_inode_lock_ex(nip);
 822                 hammer2_chain_modify(hmp, &nip->chain, 0);
 823                 ++nip->ip_data.nlinks;
 824                 hammer2_inode_unlock_ex(nip);
 825                 return (0);
 826         }
 827
 828         /*
 829          * Create a hidden inode directory entry in the parent, copying
 830          * (*oip)'s state.  Then replace oip with OBJTYPE_HARDLINK.
 831          *
 832          * The duplication function will either flush or move any chains
 833          * under oip to the new hardlink target inode, retiring all chains
 834          * related to oip before returning.  XXX vp->ip races.
 835          */
 836         error = hammer2_inode_duplicate(fdip, oip, &nip, NULL, 0);
 837         if (error == 0) {
 838                 /*
 839                  * Bump nlinks on duplicated hidden inode.
 840                  */
 841                 kprintf("hardlink consolidation success in parent dir %s\n",
 842                         fdip->ip_data.filename);
 843                 hammer2_inode_lock_nlinks(nip);
 844                 hammer2_inode_unlock_nlinks(oip);
 845                 hammer2_chain_modify(hmp, &nip->chain, 0);
 846                 ++nip->ip_data.nlinks;
 847                 hammer2_inode_unlock_ex(nip);
 848
 849                 if (oip->ip_data.name_key & HAMMER2_DIRHASH_VISIBLE) {
 850                         /*
 851                          * Replace the old inode with an OBJTYPE_HARDLINK
 852                          * pointer.
 853                          */
 854                         hammer2_inode_lock_ex(oip);
 855                         hammer2_chain_modify(hmp, &oip->chain, 0);
 856                         oip->ip_data.target_type = oip->ip_data.type;
 857                         oip->ip_data.type = HAMMER2_OBJTYPE_HARDLINK;
 858                         oip->ip_data.uflags = 0;
 859                         oip->ip_data.rmajor = 0;
 860                         oip->ip_data.rminor = 0;
 861                         oip->ip_data.ctime = 0;
 862                         oip->ip_data.mtime = 0;
 863                         oip->ip_data.atime = 0;
 864                         oip->ip_data.btime = 0;
 865                         bzero(&oip->ip_data.uid, sizeof(oip->ip_data.uid));
 866                         bzero(&oip->ip_data.gid, sizeof(oip->ip_data.gid));
 867                         oip->ip_data.op_flags = HAMMER2_OPFLAG_DIRECTDATA;
 868                         oip->ip_data.cap_flags = 0;
 869                         oip->ip_data.mode = 0;
 870                         oip->ip_data.size = 0;
 871                         oip->ip_data.nlinks = 1;
 872                         oip->ip_data.iparent = 0;       /* XXX */
 873                         oip->ip_data.pfs_type = 0;
 874                         oip->ip_data.pfs_inum = 0;
 875                         bzero(&oip->ip_data.pfs_id,
 876                               sizeof(oip->ip_data.pfs_id));
 877                         bzero(&oip->ip_data.pfs_fsid,
 878                               sizeof(oip->ip_data.pfs_fsid));
 879                         oip->ip_data.data_quota = 0;
 880                         oip->ip_data.data_count = 0;
 881                         oip->ip_data.inode_quota = 0;
 882                         oip->ip_data.inode_count = 0;
 883                         oip->ip_data.attr_tid = 0;
 884                         oip->ip_data.dirent_tid = 0;
 885                         bzero(&oip->ip_data.u, sizeof(oip->ip_data.u));
 886                         /* XXX transaction ids */
 887
 888                         hammer2_inode_unlock_ex(oip);
 889                 } else {
 890                         /*
 891                          * The old inode was a hardlink target, which we
 892                          * have now moved.  We must delete it so the new
 893                          * hardlink target at a higher directory level
 894                          * becomes the only hardlink target for this inode.
 895                          */
 896                         kprintf("DELETE INVISIBLE\n");
 897                         parent = oip->chain.parent;
 898                         hammer2_chain_lock(hmp, parent,
 899                                            HAMMER2_RESOLVE_ALWAYS);
 900                         hammer2_chain_lock(hmp, &oip->chain,
 901                                            HAMMER2_RESOLVE_ALWAYS);
 902                         hammer2_chain_delete(hmp, parent, &oip->chain);
 903                         hammer2_chain_unlock(hmp, &oip->chain);
 904                         hammer2_chain_unlock(hmp, parent);
 905                 }
 906                 *ipp = nip;
 907         } else {
 908                 KKASSERT(nip == NULL);
 909         }
 910
 911         return (error);
 912 }
 913
 914 /*
 915  * If (*ipp) is non-NULL it points to the forward OBJTYPE_HARDLINK inode while
 916  * (*chainp) points to the resolved (hidden hardlink target) inode.  In this
 917  * situation when nlinks is 1 we wish to deconsolidate the hardlink, moving
 918  * it back to the directory that now represents the only remaining link.
 919  */
 920 int
 921 hammer2_hardlink_deconsolidate(hammer2_inode_t *dip, hammer2_chain_t **chainp,
 922                                hammer2_inode_t **ipp)
 923 {
 924         if (*ipp == NULL)
 925                 return (0);
 926         /* XXX */
 927         return (0);
 928 }
 929
 930 /*
 931  * When presented with a (*chainp) representing an inode of type
 932  * OBJTYPE_HARDLINK this code will save the original inode (with a ref)
 933  * in (*ipp), and then locate the hidden hardlink target in (dip) or
 934  * any parent directory above (dip).  The locked (*chainp) is replaced
 935  * with a new locked (*chainp) representing the hardlink target.
 936  */
 937 int
 938 hammer2_hardlink_find(hammer2_inode_t *dip, hammer2_chain_t **chainp,
 939                       hammer2_inode_t **ipp)
 940 {
 941         hammer2_mount_t *hmp = dip->hmp;
 942         hammer2_chain_t *chain = *chainp;
 943         hammer2_chain_t *parent;
 944         hammer2_inode_t *pip;
 945         hammer2_key_t lhc;
 946
 947         *ipp = chain->u.ip;
 948         hammer2_inode_ref(chain->u.ip);
 949         lhc = chain->u.ip->ip_data.inum;
 950
 951         hammer2_inode_unlock_ex(chain->u.ip);
 952         pip = chain->u.ip->pip;
 953
 954         chain = NULL;
 955         while (pip) {
 956                 parent = &pip->chain;
 957                 KKASSERT(parent->bref.type == HAMMER2_BREF_TYPE_INODE);
 958
 959                 hammer2_chain_lock(hmp, parent, HAMMER2_RESOLVE_ALWAYS);
 960                 chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
 961                 if (chain) {
 962                         kprintf("found hardlink in dir %s\n",
 963                                 pip->ip_data.filename);
 964                 }
 965                 hammer2_chain_unlock(hmp, parent);
 966                 if (chain)
 967                         break;
 968                 pip = pip->pip;
 969         }
 970         *chainp = chain;
 971         if (chain) {
 972                 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
 973                 /* already locked */
 974                 return (0);
 975         } else {
 976                 return (EIO);
 977         }
 978 }