sys/vfs/hammer/hammer_inode.c

   1 /*
   2  * Copyright (c) 2007-2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sys/vfs/hammer/hammer_inode.c,v 1.50 2008/05/04 09:06:45 dillon Exp $
  35  */
  36
  37 #include "hammer.h"
  38 #include <vm/vm_extern.h>
  39 #include <sys/buf.h>
  40 #include <sys/buf2.h>
  41
  42 static int hammer_unload_inode(struct hammer_inode *ip);
  43 static void hammer_flush_inode_core(hammer_inode_t ip, int flags);
  44 static int hammer_setup_child_callback(hammer_record_t rec, void *data);
  45 static int hammer_setup_parent_inodes(hammer_record_t record);
  46
  47 /*
  48  * The kernel is not actively referencing this vnode but is still holding
  49  * it cached.
  50  *
  51  * This is called from the frontend.
  52  */
  53 int
  54 hammer_vop_inactive(struct vop_inactive_args *ap)
  55 {
  56         struct hammer_inode *ip = VTOI(ap->a_vp);
  57
  58         /*
  59          * Degenerate case
  60          */
  61         if (ip == NULL) {
  62                 vrecycle(ap->a_vp);
  63                 return(0);
  64         }
  65
  66         /*
  67          * If the inode no longer has visibility in the filesystem and is
  68          * fairly clean, try to recycle it immediately.  This can deadlock
  69          * in vfsync() if we aren't careful.
  70          */
  71         hammer_inode_unloadable_check(ip, 0);
  72         if (ip->flags & HAMMER_INODE_MODMASK)
  73                 hammer_flush_inode(ip, 0);
  74         else if (ip->ino_rec.ino_nlinks == 0)
  75                 vrecycle(ap->a_vp);
  76         return(0);
  77 }
  78
  79 /*
  80  * Release the vnode association.  This is typically (but not always)
  81  * the last reference on the inode.
  82  *
  83  * Once the association is lost we are on our own with regards to
  84  * flushing the inode.
  85  */
  86 int
  87 hammer_vop_reclaim(struct vop_reclaim_args *ap)
  88 {
  89         struct hammer_inode *ip;
  90         struct vnode *vp;
  91
  92         vp = ap->a_vp;
  93
  94         if ((ip = vp->v_data) != NULL) {
  95                 vp->v_data = NULL;
  96                 ip->vp = NULL;
  97                 hammer_rel_inode(ip, 1);
  98         }
  99         return(0);
 100 }
 101
 102 /*
 103  * Return a locked vnode for the specified inode.  The inode must be
 104  * referenced but NOT LOCKED on entry and will remain referenced on
 105  * return.
 106  *
 107  * Called from the frontend.
 108  */
 109 int
 110 hammer_get_vnode(struct hammer_inode *ip, struct vnode **vpp)
 111 {
 112         struct vnode *vp;
 113         int error = 0;
 114
 115         for (;;) {
 116                 if ((vp = ip->vp) == NULL) {
 117                         error = getnewvnode(VT_HAMMER, ip->hmp->mp, vpp, 0, 0);
 118                         if (error)
 119                                 break;
 120                         hammer_lock_ex(&ip->lock);
 121                         if (ip->vp != NULL) {
 122                                 hammer_unlock(&ip->lock);
 123                                 vp->v_type = VBAD;
 124                                 vx_put(vp);
 125                                 continue;
 126                         }
 127                         hammer_ref(&ip->lock);
 128                         vp = *vpp;
 129                         ip->vp = vp;
 130                         vp->v_type = hammer_get_vnode_type(
 131                                             ip->ino_rec.base.base.obj_type);
 132
 133                         switch(ip->ino_rec.base.base.obj_type) {
 134                         case HAMMER_OBJTYPE_CDEV:
 135                         case HAMMER_OBJTYPE_BDEV:
 136                                 vp->v_ops = &ip->hmp->mp->mnt_vn_spec_ops;
 137                                 addaliasu(vp, ip->ino_data.rmajor,
 138                                           ip->ino_data.rminor);
 139                                 break;
 140                         case HAMMER_OBJTYPE_FIFO:
 141                                 vp->v_ops = &ip->hmp->mp->mnt_vn_fifo_ops;
 142                                 break;
 143                         default:
 144                                 break;
 145                         }
 146
 147                         /*
 148                          * Only mark as the root vnode if the ip is not
 149                          * historical, otherwise the VFS cache will get
 150                          * confused.  The other half of the special handling
 151                          * is in hammer_vop_nlookupdotdot().
 152                          */
 153                         if (ip->obj_id == HAMMER_OBJID_ROOT &&
 154                             ip->obj_asof == ip->hmp->asof) {
 155                                 vp->v_flag |= VROOT;
 156                         }
 157
 158                         vp->v_data = (void *)ip;
 159                         /* vnode locked by getnewvnode() */
 160                         /* make related vnode dirty if inode dirty? */
 161                         hammer_unlock(&ip->lock);
 162                         if (vp->v_type == VREG)
 163                                 vinitvmio(vp, ip->ino_rec.ino_size);
 164                         break;
 165                 }
 166
 167                 /*
 168                  * loop if the vget fails (aka races), or if the vp
 169                  * no longer matches ip->vp.
 170                  */
 171                 if (vget(vp, LK_EXCLUSIVE) == 0) {
 172                         if (vp == ip->vp)
 173                                 break;
 174                         vput(vp);
 175                 }
 176         }
 177         *vpp = vp;
 178         return(error);
 179 }
 180
 181 /*
 182  * Acquire a HAMMER inode.  The returned inode is not locked.  These functions
 183  * do not attach or detach the related vnode (use hammer_get_vnode() for
 184  * that).
 185  *
 186  * The flags argument is only applied for newly created inodes, and only
 187  * certain flags are inherited.
 188  *
 189  * Called from the frontend.
 190  */
 191 struct hammer_inode *
 192 hammer_get_inode(hammer_transaction_t trans, struct hammer_node **cache,
 193                  u_int64_t obj_id, hammer_tid_t asof, int flags, int *errorp)
 194 {
 195         hammer_mount_t hmp = trans->hmp;
 196         struct hammer_inode_info iinfo;
 197         struct hammer_cursor cursor;
 198         struct hammer_inode *ip;
 199
 200         /*
 201          * Determine if we already have an inode cached.  If we do then
 202          * we are golden.
 203          */
 204         iinfo.obj_id = obj_id;
 205         iinfo.obj_asof = asof;
 206 loop:
 207         ip = hammer_ino_rb_tree_RB_LOOKUP_INFO(&hmp->rb_inos_root, &iinfo);
 208         if (ip) {
 209                 hammer_ref(&ip->lock);
 210                 *errorp = 0;
 211                 return(ip);
 212         }
 213
 214         ip = kmalloc(sizeof(*ip), M_HAMMER, M_WAITOK|M_ZERO);
 215         ++hammer_count_inodes;
 216         ip->obj_id = obj_id;
 217         ip->obj_asof = iinfo.obj_asof;
 218         ip->hmp = hmp;
 219         ip->flags = flags & HAMMER_INODE_RO;
 220         if (hmp->ronly)
 221                 ip->flags |= HAMMER_INODE_RO;
 222         ip->trunc_off = 0x7FFFFFFFFFFFFFFFLL;
 223         RB_INIT(&ip->rec_tree);
 224         TAILQ_INIT(&ip->bio_list);
 225         TAILQ_INIT(&ip->bio_alt_list);
 226         TAILQ_INIT(&ip->target_list);
 227
 228         /*
 229          * Locate the on-disk inode.
 230          */
 231 retry:
 232         hammer_init_cursor(trans, &cursor, cache, NULL);
 233         cursor.key_beg.obj_id = ip->obj_id;
 234         cursor.key_beg.key = 0;
 235         cursor.key_beg.create_tid = 0;
 236         cursor.key_beg.delete_tid = 0;
 237         cursor.key_beg.rec_type = HAMMER_RECTYPE_INODE;
 238         cursor.key_beg.obj_type = 0;
 239         cursor.asof = iinfo.obj_asof;
 240         cursor.flags = HAMMER_CURSOR_GET_RECORD | HAMMER_CURSOR_GET_DATA |
 241                        HAMMER_CURSOR_ASOF;
 242
 243         *errorp = hammer_btree_lookup(&cursor);
 244         if (*errorp == EDEADLK) {
 245                 hammer_done_cursor(&cursor);
 246                 goto retry;
 247         }
 248
 249         /*
 250          * On success the B-Tree lookup will hold the appropriate
 251          * buffer cache buffers and provide a pointer to the requested
 252          * information.  Copy the information to the in-memory inode
 253          * and cache the B-Tree node to improve future operations.
 254          */
 255         if (*errorp == 0) {
 256                 ip->ino_rec = cursor.record->inode;
 257                 ip->ino_data = cursor.data->inode;
 258                 hammer_cache_node(cursor.node, &ip->cache[0]);
 259                 if (cache)
 260                         hammer_cache_node(cursor.node, cache);
 261         }
 262
 263         /*
 264          * On success load the inode's record and data and insert the
 265          * inode into the B-Tree.  It is possible to race another lookup
 266          * insertion of the same inode so deal with that condition too.
 267          *
 268          * The cursor's locked node interlocks against others creating and
 269          * destroying ip while we were blocked.
 270          */
 271         if (*errorp == 0) {
 272                 hammer_ref(&ip->lock);
 273                 if (RB_INSERT(hammer_ino_rb_tree, &hmp->rb_inos_root, ip)) {
 274                         hammer_uncache_node(&ip->cache[0]);
 275                         hammer_uncache_node(&ip->cache[1]);
 276                         KKASSERT(ip->lock.refs == 1);
 277                         --hammer_count_inodes;
 278                         kfree(ip, M_HAMMER);
 279                         hammer_done_cursor(&cursor);
 280                         goto loop;
 281                 }
 282                 ip->flags |= HAMMER_INODE_ONDISK;
 283         } else {
 284                 kprintf("hammer_get_inode: failed ip %p cursor %p error %d\n",
 285                         ip, &cursor, *errorp);
 286                 /*Debugger("x");*/
 287                 --hammer_count_inodes;
 288                 kfree(ip, M_HAMMER);
 289                 ip = NULL;
 290         }
 291         hammer_done_cursor(&cursor);
 292         return (ip);
 293 }
 294
 295 /*
 296  * Create a new filesystem object, returning the inode in *ipp.  The
 297  * returned inode will be referenced.
 298  *
 299  * The inode is created in-memory.
 300  */
 301 int
 302 hammer_create_inode(hammer_transaction_t trans, struct vattr *vap,
 303                     struct ucred *cred, hammer_inode_t dip,
 304                     struct hammer_inode **ipp)
 305 {
 306         hammer_mount_t hmp;
 307         hammer_inode_t ip;
 308         uid_t xuid;
 309
 310         hmp = trans->hmp;
 311         ip = kmalloc(sizeof(*ip), M_HAMMER, M_WAITOK|M_ZERO);
 312         ++hammer_count_inodes;
 313         ip->obj_id = hammer_alloc_objid(trans, dip);
 314         KKASSERT(ip->obj_id != 0);
 315         ip->obj_asof = hmp->asof;
 316         ip->hmp = hmp;
 317         ip->flush_state = HAMMER_FST_IDLE;
 318         ip->flags = HAMMER_INODE_DDIRTY | HAMMER_INODE_RDIRTY |
 319                     HAMMER_INODE_ITIMES;
 320
 321         ip->trunc_off = 0x7FFFFFFFFFFFFFFFLL;
 322         RB_INIT(&ip->rec_tree);
 323         TAILQ_INIT(&ip->bio_list);
 324         TAILQ_INIT(&ip->bio_alt_list);
 325         TAILQ_INIT(&ip->target_list);
 326
 327         ip->ino_rec.ino_atime = trans->time;
 328         ip->ino_rec.ino_mtime = trans->time;
 329         ip->ino_rec.ino_size = 0;
 330         ip->ino_rec.ino_nlinks = 0;
 331         /* XXX */
 332         ip->ino_rec.base.base.btype = HAMMER_BTREE_TYPE_RECORD;
 333         ip->ino_rec.base.base.obj_id = ip->obj_id;
 334         ip->ino_rec.base.base.key = 0;
 335         ip->ino_rec.base.base.create_tid = 0;
 336         ip->ino_rec.base.base.delete_tid = 0;
 337         ip->ino_rec.base.base.rec_type = HAMMER_RECTYPE_INODE;
 338         ip->ino_rec.base.base.obj_type = hammer_get_obj_type(vap->va_type);
 339
 340         ip->ino_data.version = HAMMER_INODE_DATA_VERSION;
 341         ip->ino_data.mode = vap->va_mode;
 342         ip->ino_data.ctime = trans->time;
 343         ip->ino_data.parent_obj_id = (dip) ? dip->ino_rec.base.base.obj_id : 0;
 344
 345         switch(ip->ino_rec.base.base.obj_type) {
 346         case HAMMER_OBJTYPE_CDEV:
 347         case HAMMER_OBJTYPE_BDEV:
 348                 ip->ino_data.rmajor = vap->va_rmajor;
 349                 ip->ino_data.rminor = vap->va_rminor;
 350                 break;
 351         default:
 352                 break;
 353         }
 354
 355         /*
 356          * Calculate default uid/gid and overwrite with information from
 357          * the vap.
 358          */
 359         xuid = hammer_to_unix_xid(&dip->ino_data.uid);
 360         ip->ino_data.gid = dip->ino_data.gid;
 361         xuid = vop_helper_create_uid(hmp->mp, dip->ino_data.mode, xuid, cred,
 362                                      &vap->va_mode);
 363         ip->ino_data.mode = vap->va_mode;
 364
 365         if (vap->va_vaflags & VA_UID_UUID_VALID)
 366                 ip->ino_data.uid = vap->va_uid_uuid;
 367         else if (vap->va_uid != (uid_t)VNOVAL)
 368                 hammer_guid_to_uuid(&ip->ino_data.uid, xuid);
 369         if (vap->va_vaflags & VA_GID_UUID_VALID)
 370                 ip->ino_data.gid = vap->va_gid_uuid;
 371         else if (vap->va_gid != (gid_t)VNOVAL)
 372                 hammer_guid_to_uuid(&ip->ino_data.gid, vap->va_gid);
 373
 374         hammer_ref(&ip->lock);
 375         if (RB_INSERT(hammer_ino_rb_tree, &hmp->rb_inos_root, ip)) {
 376                 hammer_unref(&ip->lock);
 377                 panic("hammer_create_inode: duplicate obj_id %llx", ip->obj_id);
 378         }
 379         *ipp = ip;
 380         return(0);
 381 }
 382
 383 /*
 384  * Called by hammer_sync_inode().
 385  */
 386 static int
 387 hammer_update_inode(hammer_cursor_t cursor, hammer_inode_t ip)
 388 {
 389         hammer_transaction_t trans = cursor->trans;
 390         hammer_record_t record;
 391         int error;
 392
 393 retry:
 394         error = 0;
 395
 396         /*
 397          * If the inode has a presence on-disk then locate it and mark
 398          * it deleted, setting DELONDISK.
 399          *
 400          * The record may or may not be physically deleted, depending on
 401          * the retention policy.
 402          */
 403         if ((ip->flags & (HAMMER_INODE_ONDISK|HAMMER_INODE_DELONDISK)) ==
 404             HAMMER_INODE_ONDISK) {
 405                 hammer_normalize_cursor(cursor);
 406                 cursor->key_beg.obj_id = ip->obj_id;
 407                 cursor->key_beg.key = 0;
 408                 cursor->key_beg.create_tid = 0;
 409                 cursor->key_beg.delete_tid = 0;
 410                 cursor->key_beg.rec_type = HAMMER_RECTYPE_INODE;
 411                 cursor->key_beg.obj_type = 0;
 412                 cursor->asof = ip->obj_asof;
 413                 cursor->flags &= ~HAMMER_CURSOR_INITMASK;
 414                 cursor->flags |= HAMMER_CURSOR_GET_RECORD | HAMMER_CURSOR_ASOF;
 415                 cursor->flags |= HAMMER_CURSOR_BACKEND;
 416
 417                 error = hammer_btree_lookup(cursor);
 418                 if (hammer_debug_inode)
 419                         kprintf("IPDEL %p %08x %d", ip, ip->flags, error);
 420                 if (error) {
 421                         kprintf("error %d\n", error);
 422                         Debugger("hammer_update_inode");
 423                 }
 424
 425                 if (error == 0) {
 426                         error = hammer_ip_delete_record(cursor, trans->tid);
 427                         if (hammer_debug_inode)
 428                                 kprintf(" error %d\n", error);
 429                         if (error && error != EDEADLK) {
 430                                 kprintf("error %d\n", error);
 431                                 Debugger("hammer_update_inode2");
 432                         }
 433                         if (error == 0) {
 434                                 ip->flags |= HAMMER_INODE_DELONDISK;
 435                         }
 436                         if (cursor->node)
 437                                 hammer_cache_node(cursor->node, &ip->cache[0]);
 438                 }
 439                 if (error == EDEADLK) {
 440                         hammer_done_cursor(cursor);
 441                         error = hammer_init_cursor(trans, cursor,
 442                                                    &ip->cache[0], ip);
 443                         if (hammer_debug_inode)
 444                                 kprintf("IPDED %p %d\n", ip, error);
 445                         if (error == 0)
 446                                 goto retry;
 447                 }
 448         }
 449
 450         /*
 451          * Ok, write out the initial record or a new record (after deleting
 452          * the old one), unless the DELETED flag is set.  This routine will
 453          * clear DELONDISK if it writes out a record.
 454          *
 455          * Update our inode statistics if this is the first application of
 456          * the inode on-disk.
 457          */
 458         if (error == 0 && (ip->flags & HAMMER_INODE_DELETED) == 0) {
 459                 /*
 460                  * Generate a record and write it to the media
 461                  */
 462                 record = hammer_alloc_mem_record(ip);
 463                 record->type = HAMMER_MEM_RECORD_GENERAL;
 464                 record->flush_state = HAMMER_FST_FLUSH;
 465                 record->rec.inode = ip->sync_ino_rec;
 466                 record->rec.inode.base.base.create_tid = trans->tid;
 467                 record->rec.inode.base.data_len = sizeof(ip->sync_ino_data);
 468                 record->data = (void *)&ip->sync_ino_data;
 469                 record->flags |= HAMMER_RECF_INTERLOCK_BE;
 470                 for (;;) {
 471                         error = hammer_ip_sync_record_cursor(cursor, record);
 472                         if (hammer_debug_inode)
 473                                 kprintf("GENREC %p rec %08x %d\n",
 474                                         ip, record->flags, error);
 475                         if (error != EDEADLK)
 476                                 break;
 477                         hammer_done_cursor(cursor);
 478                         error = hammer_init_cursor(trans, cursor,
 479                                                    &ip->cache[0], ip);
 480                         if (hammer_debug_inode)
 481                                 kprintf("GENREC reinit %d\n", error);
 482                         if (error)
 483                                 break;
 484                 }
 485                 if (error) {
 486                         kprintf("error %d\n", error);
 487                         Debugger("hammer_update_inode3");
 488                 }
 489
 490                 /*
 491                  * The record isn't managed by the inode's record tree,
 492                  * destroy it whether we succeed or fail.
 493                  */
 494                 record->flags &= ~HAMMER_RECF_INTERLOCK_BE;
 495                 record->flags |= HAMMER_RECF_DELETED_FE;
 496                 record->flush_state = HAMMER_FST_IDLE;
 497                 hammer_rel_mem_record(record);
 498
 499                 /*
 500                  * Finish up.
 501                  */
 502                 if (error == 0) {
 503                         if (hammer_debug_inode)
 504                                 kprintf("CLEANDELOND %p %08x\n", ip, ip->flags);
 505                         ip->sync_flags &= ~(HAMMER_INODE_RDIRTY |
 506                                             HAMMER_INODE_DDIRTY |
 507                                             HAMMER_INODE_ITIMES);
 508                         ip->flags &= ~HAMMER_INODE_DELONDISK;
 509
 510                         /*
 511                          * Root volume count of inodes
 512                          */
 513                         if ((ip->flags & HAMMER_INODE_ONDISK) == 0) {
 514                                 hammer_modify_volume_field(trans,
 515                                                            trans->rootvol,
 516                                                            vol0_stat_inodes);
 517                                 ++ip->hmp->rootvol->ondisk->vol0_stat_inodes;
 518                                 hammer_modify_volume_done(trans->rootvol);
 519                                 ip->flags |= HAMMER_INODE_ONDISK;
 520                                 if (hammer_debug_inode)
 521                                         kprintf("NOWONDISK %p\n", ip);
 522                         }
 523                 }
 524         }
 525
 526         /*
 527          * If the inode has been destroyed, clean out any left-over flags
 528          * that may have been set by the frontend.
 529          */
 530         if (error == 0 && (ip->flags & HAMMER_INODE_DELETED)) {
 531                 ip->sync_flags &= ~(HAMMER_INODE_RDIRTY |
 532                                     HAMMER_INODE_DDIRTY |
 533                                     HAMMER_INODE_ITIMES);
 534         }
 535         return(error);
 536 }
 537
 538 /*
 539  * Update only the itimes fields.  This is done no-historically.  The
 540  * record is updated in-place on the disk.
 541  */
 542 static int
 543 hammer_update_itimes(hammer_cursor_t cursor, hammer_inode_t ip)
 544 {
 545         hammer_transaction_t trans = cursor->trans;
 546         struct hammer_inode_record *rec;
 547         int error;
 548
 549 retry:
 550         error = 0;
 551         if ((ip->flags & (HAMMER_INODE_ONDISK|HAMMER_INODE_DELONDISK)) ==
 552             HAMMER_INODE_ONDISK) {
 553                 hammer_normalize_cursor(cursor);
 554                 cursor->key_beg.obj_id = ip->obj_id;
 555                 cursor->key_beg.key = 0;
 556                 cursor->key_beg.create_tid = 0;
 557                 cursor->key_beg.delete_tid = 0;
 558                 cursor->key_beg.rec_type = HAMMER_RECTYPE_INODE;
 559                 cursor->key_beg.obj_type = 0;
 560                 cursor->asof = ip->obj_asof;
 561                 cursor->flags &= ~HAMMER_CURSOR_INITMASK;
 562                 cursor->flags |= HAMMER_CURSOR_GET_RECORD | HAMMER_CURSOR_ASOF;
 563                 cursor->flags |= HAMMER_CURSOR_BACKEND;
 564
 565                 error = hammer_btree_lookup(cursor);
 566                 if (error) {
 567                         kprintf("error %d\n", error);
 568                         Debugger("hammer_update_itimes1");
 569                 }
 570                 if (error == 0) {
 571                         /*
 572                          * Do not generate UNDO records for atime/mtime
 573                          * updates.
 574                          */
 575                         rec = &cursor->record->inode;
 576                         hammer_modify_buffer(trans, cursor->record_buffer,
 577                                              NULL, 0);
 578                         rec->ino_atime = ip->sync_ino_rec.ino_atime;
 579                         rec->ino_mtime = ip->sync_ino_rec.ino_mtime;
 580                         hammer_modify_buffer_done(cursor->record_buffer);
 581                         ip->sync_flags &= ~HAMMER_INODE_ITIMES;
 582                         /* XXX recalculate crc */
 583                         hammer_cache_node(cursor->node, &ip->cache[0]);
 584                 }
 585                 if (error == EDEADLK) {
 586                         hammer_done_cursor(cursor);
 587                         error = hammer_init_cursor(trans, cursor,
 588                                                    &ip->cache[0], ip);
 589                         if (error == 0)
 590                                 goto retry;
 591                 }
 592         }
 593         return(error);
 594 }
 595
 596 /*
 597  * Release a reference on an inode, flush as requested.
 598  *
 599  * On the last reference we queue the inode to the flusher for its final
 600  * disposition.
 601  */
 602 void
 603 hammer_rel_inode(struct hammer_inode *ip, int flush)
 604 {
 605         hammer_mount_t hmp = ip->hmp;
 606
 607         /*
 608          * Handle disposition when dropping the last ref.
 609          */
 610         for (;;) {
 611                 if (ip->lock.refs == 1) {
 612                         /*
 613                          * Determine whether on-disk action is needed for
 614                          * the inode's final disposition.
 615                          */
 616                         KKASSERT(ip->vp == NULL);
 617                         hammer_inode_unloadable_check(ip, 0);
 618                         if (ip->flags & HAMMER_INODE_MODMASK) {
 619                                 hammer_flush_inode(ip, 0);
 620                         } else if (ip->lock.refs == 1) {
 621                                 hammer_unload_inode(ip);
 622                                 break;
 623                         }
 624                 } else {
 625                         if (flush)
 626                                 hammer_flush_inode(ip, 0);
 627
 628                         /*
 629                          * The inode still has multiple refs, try to drop
 630                          * one ref.
 631                          */
 632                         KKASSERT(ip->lock.refs >= 1);
 633                         if (ip->lock.refs > 1) {
 634                                 hammer_unref(&ip->lock);
 635                                 break;
 636                         }
 637                 }
 638         }
 639
 640         /*
 641          * XXX bad hack until I add code to track inodes in SETUP.  We
 642          * can queue a lot of inodes to the syncer but if we don't wake
 643          * it up the undo sets will be too large or too many unflushed
 644          * records will build up and blow our malloc limit.
 645          */
 646         if (++hmp->reclaim_count > 256) {
 647                 hmp->reclaim_count = 0;
 648                 hammer_flusher_async(hmp);
 649         }
 650 }
 651
 652 /*
 653  * Unload and destroy the specified inode.  Must be called with one remaining
 654  * reference.  The reference is disposed of.
 655  *
 656  * This can only be called in the context of the flusher.
 657  */
 658 static int
 659 hammer_unload_inode(struct hammer_inode *ip)
 660 {
 661         KASSERT(ip->lock.refs == 1,
 662                 ("hammer_unload_inode: %d refs\n", ip->lock.refs));
 663         KKASSERT(ip->vp == NULL);
 664         KKASSERT(ip->flush_state == HAMMER_FST_IDLE);
 665         KKASSERT(ip->cursor_ip_refs == 0);
 666         KKASSERT((ip->flags & HAMMER_INODE_MODMASK) == 0);
 667
 668         KKASSERT(RB_EMPTY(&ip->rec_tree));
 669         KKASSERT(TAILQ_EMPTY(&ip->target_list));
 670         KKASSERT(TAILQ_EMPTY(&ip->bio_list));
 671         KKASSERT(TAILQ_EMPTY(&ip->bio_alt_list));
 672
 673         RB_REMOVE(hammer_ino_rb_tree, &ip->hmp->rb_inos_root, ip);
 674
 675         hammer_uncache_node(&ip->cache[0]);
 676         hammer_uncache_node(&ip->cache[1]);
 677         if (ip->objid_cache)
 678                 hammer_clear_objid(ip);
 679         --hammer_count_inodes;
 680         kfree(ip, M_HAMMER);
 681
 682         return(0);
 683 }
 684
 685 /*
 686  * A transaction has modified an inode, requiring updates as specified by
 687  * the passed flags.
 688  *
 689  * HAMMER_INODE_RDIRTY: Inode record has been updated
 690  * HAMMER_INODE_DDIRTY: Inode data has been updated
 691  * HAMMER_INODE_XDIRTY: Dirty in-memory records
 692  * HAMMER_INODE_BUFS:   Dirty buffer cache buffers
 693  * HAMMER_INODE_DELETED: Inode record/data must be deleted
 694  * HAMMER_INODE_ITIMES: mtime/atime has been updated
 695  */
 696 void
 697 hammer_modify_inode(hammer_transaction_t trans, hammer_inode_t ip, int flags)
 698 {
 699         KKASSERT ((ip->flags & HAMMER_INODE_RO) == 0 ||
 700                   (flags & (HAMMER_INODE_RDIRTY|HAMMER_INODE_DDIRTY|
 701                    HAMMER_INODE_XDIRTY|HAMMER_INODE_BUFS|
 702                    HAMMER_INODE_DELETED|HAMMER_INODE_ITIMES)) == 0);
 703
 704         ip->flags |= flags;
 705 }
 706
 707 /*
 708  * Request that an inode be flushed.  This whole mess cannot block and may
 709  * recurse.  Once requested HAMMER will attempt to actively flush it until
 710  * the flush can be done.
 711  *
 712  * The inode may already be flushing, or may be in a setup state.  We can
 713  * place the inode in a flushing state if it is currently idle and flag it
 714  * to reflush if it is currently flushing.
 715  */
 716 void
 717 hammer_flush_inode(hammer_inode_t ip, int flags)
 718 {
 719         hammer_record_t depend;
 720         int r, good;
 721
 722         /*
 723          * Trivial 'nothing to flush' case.  If the inode is ina SETUP
 724          * state we have to put it back into an IDLE state so we can
 725          * drop the extra ref.
 726          */
 727         if ((ip->flags & HAMMER_INODE_MODMASK) == 0) {
 728                 if (ip->flush_state == HAMMER_FST_SETUP) {
 729                         ip->flush_state = HAMMER_FST_IDLE;
 730                         hammer_rel_inode(ip, 0);
 731                 }
 732                 return;
 733         }
 734
 735         /*
 736          * Our flush action will depend on the current state.
 737          */
 738         switch(ip->flush_state) {
 739         case HAMMER_FST_IDLE:
 740                 /*
 741                  * We have no dependancies and can flush immediately.  Some
 742                  * our children may not be flushable so we have to re-test
 743                  * with that additional knowledge.
 744                  */
 745                 hammer_flush_inode_core(ip, flags);
 746                 break;
 747         case HAMMER_FST_SETUP:
 748                 /*
 749                  * Recurse upwards through dependancies via target_list
 750                  * and start their flusher actions going if possible.
 751                  *
 752                  * 'good' is our connectivity.  -1 means we have none and
 753                  * can't flush, 0 means there weren't any dependancies, and
 754                  * 1 means we have good connectivity.
 755                  */
 756                 good = 0;
 757                 TAILQ_FOREACH(depend, &ip->target_list, target_entry) {
 758                         r = hammer_setup_parent_inodes(depend);
 759                         if (r < 0 && good == 0)
 760                                 good = -1;
 761                         if (r > 0)
 762                                 good = 1;
 763                 }
 764
 765                 /*
 766                  * We can continue if good >= 0.  Determine how many records
 767                  * under our inode can be flushed (and mark them).
 768                  */
 769                 if (good >= 0) {
 770                         hammer_flush_inode_core(ip, flags);
 771                 } else {
 772                         ip->flags |= HAMMER_INODE_REFLUSH;
 773                         if (flags & HAMMER_FLUSH_SIGNAL) {
 774                                 ip->flags |= HAMMER_INODE_RESIGNAL;
 775                                 hammer_flusher_async(ip->hmp);
 776                         }
 777                 }
 778                 break;
 779         default:
 780                 /*
 781                  * We are already flushing, flag the inode to reflush
 782                  * if needed after it completes its current flush.
 783                  */
 784                 if ((ip->flags & HAMMER_INODE_REFLUSH) == 0)
 785                         ip->flags |= HAMMER_INODE_REFLUSH;
 786                 if (flags & HAMMER_FLUSH_SIGNAL) {
 787                         ip->flags |= HAMMER_INODE_RESIGNAL;
 788                         hammer_flusher_async(ip->hmp);
 789                 }
 790                 break;
 791         }
 792 }
 793
 794 /*
 795  * We are asked to recurse upwards and convert the record from SETUP
 796  * to FLUSH if possible.  record->ip is a parent of the caller's inode,
 797  * and record->target_ip is the caller's inode.
 798  *
 799  * Return 1 if the record gives us connectivity
 800  *
 801  * Return 0 if the record is not relevant
 802  *
 803  * Return -1 if we can't resolve the dependancy and there is no connectivity.
 804  */
 805 static int
 806 hammer_setup_parent_inodes(hammer_record_t record)
 807 {
 808         hammer_mount_t hmp = record->ip->hmp;
 809         hammer_record_t depend;
 810         hammer_inode_t ip;
 811         int r, good;
 812
 813         KKASSERT(record->flush_state != HAMMER_FST_IDLE);
 814         ip = record->ip;
 815
 816         /*
 817          * If the record is already flushing, is it in our flush group?
 818          *
 819          * If it is in our flush group but it is a general record or a
 820          * delete-on-disk, it does not improve our connectivity (return 0),
 821          * and if the target inode is not trying to destroy itself we can't
 822          * allow the operation yet anyway (the second return -1).
 823          */
 824         if (record->flush_state == HAMMER_FST_FLUSH) {
 825                 if (record->flush_group != hmp->flusher_next) {
 826                         ip->flags |= HAMMER_INODE_REFLUSH;
 827                         return(-1);
 828                 }
 829                 if (record->type == HAMMER_MEM_RECORD_ADD)
 830                         return(1);
 831                 /* GENERAL or DEL */
 832                 return(0);
 833         }
 834
 835         /*
 836          * It must be a setup record.  Try to resolve the setup dependancies
 837          * by recursing upwards so we can place ip on the flush list.
 838          */
 839         KKASSERT(record->flush_state == HAMMER_FST_SETUP);
 840
 841         good = 0;
 842         TAILQ_FOREACH(depend, &ip->target_list, target_entry) {
 843                 r = hammer_setup_parent_inodes(depend);
 844                 if (r < 0 && good == 0)
 845                         good = -1;
 846                 if (r > 0)
 847                         good = 1;
 848         }
 849
 850         /*
 851          * We can't flush ip because it has no connectivity (XXX also check
 852          * nlinks for pre-existing connectivity!).  Flag it so any resolution
 853          * recurses back down.
 854          */
 855         if (good < 0) {
 856                 ip->flags |= HAMMER_INODE_REFLUSH;
 857                 return(good);
 858         }
 859
 860         /*
 861          * We are go, place the parent inode in a flushing state so we can
 862          * place its record in a flushing state.  Note that the parent
 863          * may already be flushing.  The record must be in the same flush
 864          * group as the parent.
 865          */
 866         if (ip->flush_state != HAMMER_FST_FLUSH)
 867                 hammer_flush_inode_core(ip, HAMMER_FLUSH_RECURSION);
 868         KKASSERT(ip->flush_state == HAMMER_FST_FLUSH);
 869         KKASSERT(record->flush_state == HAMMER_FST_SETUP);
 870
 871 #if 0
 872         if (record->type == HAMMER_MEM_RECORD_DEL &&
 873             (record->target_ip->flags & (HAMMER_INODE_DELETED|HAMMER_INODE_DELONDISK)) == 0) {
 874                 /*
 875                  * Regardless of flushing state we cannot sync this path if the
 876                  * record represents a delete-on-disk but the target inode
 877                  * is not ready to sync its own deletion.
 878                  *
 879                  * XXX need to count effective nlinks to determine whether
 880                  * the flush is ok, otherwise removing a hardlink will
 881                  * just leave the DEL record to rot.
 882                  */
 883                 record->target_ip->flags |= HAMMER_INODE_REFLUSH;
 884                 return(-1);
 885         } else
 886 #endif
 887         if (ip->flush_group == ip->hmp->flusher_next) {
 888                 /*
 889                  * This is the record we wanted to synchronize.
 890                  */
 891                 record->flush_state = HAMMER_FST_FLUSH;
 892                 record->flush_group = ip->flush_group;
 893                 hammer_ref(&record->lock);
 894                 if (record->type == HAMMER_MEM_RECORD_ADD)
 895                         return(1);
 896
 897                 /*
 898                  * A general or delete-on-disk record does not contribute
 899                  * to our visibility.  We can still flush it, however.
 900                  */
 901                 return(0);
 902         } else {
 903                 /*
 904                  * We couldn't resolve the dependancies, request that the
 905                  * inode be flushed when the dependancies can be resolved.
 906                  */
 907                 ip->flags |= HAMMER_INODE_REFLUSH;
 908                 return(-1);
 909         }
 910 }
 911
 912 /*
 913  * This is the core routine placing an inode into the FST_FLUSH state.
 914  */
 915 static void
 916 hammer_flush_inode_core(hammer_inode_t ip, int flags)
 917 {
 918         int go_count;
 919
 920         /*
 921          * Set flush state and prevent the flusher from cycling into
 922          * the next flush group.  Do not place the ip on the list yet.
 923          * Inodes not in the idle state get an extra reference.
 924          */
 925         KKASSERT(ip->flush_state != HAMMER_FST_FLUSH);
 926         if (ip->flush_state == HAMMER_FST_IDLE)
 927                 hammer_ref(&ip->lock);
 928         ip->flush_state = HAMMER_FST_FLUSH;
 929         ip->flush_group = ip->hmp->flusher_next;
 930         ++ip->hmp->flusher_lock;
 931
 932         /*
 933          * We need to be able to vfsync/truncate from the backend.
 934          */
 935         KKASSERT((ip->flags & HAMMER_INODE_VHELD) == 0);
 936         if (ip->vp && (ip->vp->v_flag & VINACTIVE) == 0) {
 937                 ip->flags |= HAMMER_INODE_VHELD;
 938                 vref(ip->vp);
 939         }
 940
 941         /*
 942          * Figure out how many in-memory records we can actually flush
 943          * (not including inode meta-data, buffers, etc).
 944          */
 945         if (flags & HAMMER_FLUSH_RECURSION) {
 946                 go_count = 1;
 947         } else {
 948                 go_count = RB_SCAN(hammer_rec_rb_tree, &ip->rec_tree, NULL,
 949                                    hammer_setup_child_callback, NULL);
 950         }
 951
 952         /*
 953          * This is a more involved test that includes go_count.  If we
 954          * can't flush, flag the inode and return.  If go_count is 0 we
 955          * were are unable to flush any records in our rec_tree and
 956          * must ignore the XDIRTY flag.
 957          */
 958         if (go_count == 0) {
 959                 if ((ip->flags & HAMMER_INODE_MODMASK_NOXDIRTY) == 0) {
 960                         ip->flags |= HAMMER_INODE_REFLUSH;
 961                         ip->flush_state = HAMMER_FST_SETUP;
 962                         if (ip->flags & HAMMER_INODE_VHELD) {
 963                                 ip->flags &= ~HAMMER_INODE_VHELD;
 964                                 vrele(ip->vp);
 965                         }
 966                         if (flags & HAMMER_FLUSH_SIGNAL) {
 967                                 ip->flags |= HAMMER_INODE_RESIGNAL;
 968                                 hammer_flusher_async(ip->hmp);
 969                         }
 970                         if (--ip->hmp->flusher_lock == 0)
 971                                 wakeup(&ip->hmp->flusher_lock);
 972                         return;
 973                 }
 974         }
 975
 976         /*
 977          * Snapshot the state of the inode for the backend flusher.
 978          *
 979          * The truncation must be retained in the frontend until after
 980          * we've actually performed the record deletion.
 981          *
 982          * NOTE: The DELETING flag is a mod flag, but it is also sticky,
 983          * and stays in ip->flags.  Once set, it stays set until the
 984          * inode is destroyed.
 985          */
 986         ip->sync_flags = (ip->flags & HAMMER_INODE_MODMASK);
 987         ip->sync_trunc_off = ip->trunc_off;
 988         ip->sync_ino_rec = ip->ino_rec;
 989         ip->sync_ino_data = ip->ino_data;
 990         ip->flags &= ~HAMMER_INODE_MODMASK | HAMMER_INODE_TRUNCATED;
 991
 992         /*
 993          * The flusher list inherits our inode and reference.
 994          */
 995         TAILQ_INSERT_TAIL(&ip->hmp->flush_list, ip, flush_entry);
 996         if (--ip->hmp->flusher_lock == 0)
 997                 wakeup(&ip->hmp->flusher_lock);
 998
 999         if (flags & HAMMER_FLUSH_SIGNAL)
1000                 hammer_flusher_async(ip->hmp);
1001 }
1002
1003 /*
1004  * Callback for scan of ip->rec_tree.  Try to include each record in our
1005  * flush.  ip->flush_group has been set but the inode has not yet been
1006  * moved into a flushing state.
1007  *
1008  * If we get stuck on a record we have to set HAMMER_INODE_REFLUSH on
1009  * both inodes.
1010  *
1011  * We return 1 for any record placed or found in FST_FLUSH, which prevents
1012  * the caller from shortcutting the flush.
1013  */
1014 static int
1015 hammer_setup_child_callback(hammer_record_t rec, void *data)
1016 {
1017         hammer_inode_t target_ip;
1018         hammer_inode_t ip;
1019         int r;
1020
1021         /*
1022          * If the record has been deleted by the backend (it's being held
1023          * by the frontend in a race), just ignore it.
1024          */
1025         if (rec->flags & HAMMER_RECF_DELETED_BE)
1026                 return(0);
1027
1028         /*
1029          * If the record is in an idle state it has no dependancies and
1030          * can be flushed.
1031          */
1032         ip = rec->ip;
1033         r = 0;
1034
1035         switch(rec->flush_state) {
1036         case HAMMER_FST_IDLE:
1037                 /*
1038                  * Record has no setup dependancy, we can flush it.
1039                  */
1040                 KKASSERT(rec->target_ip == NULL);
1041                 rec->flush_state = HAMMER_FST_FLUSH;
1042                 rec->flush_group = ip->flush_group;
1043                 hammer_ref(&rec->lock);
1044                 r = 1;
1045                 break;
1046         case HAMMER_FST_SETUP:
1047                 /*
1048                  * Record has a setup dependancy.  Try to include the
1049                  * target ip in the flush.
1050                  *
1051                  * We have to be careful here, if we do not do the right
1052                  * thing we can lose track of dirty inodes and the system
1053                  * will lockup trying to allocate buffers.
1054                  */
1055                 target_ip = rec->target_ip;
1056                 KKASSERT(target_ip != NULL);
1057                 KKASSERT(target_ip->flush_state != HAMMER_FST_IDLE);
1058                 if (target_ip->flush_state == HAMMER_FST_FLUSH) {
1059                         /*
1060                          * If the target IP is already flushing in our group
1061                          * we are golden, otherwise make sure the target
1062                          * reflushes.
1063                          */
1064                         if (target_ip->flush_group == ip->flush_group) {
1065                                 rec->flush_state = HAMMER_FST_FLUSH;
1066                                 rec->flush_group = ip->flush_group;
1067                                 hammer_ref(&rec->lock);
1068                                 r = 1;
1069                         } else {
1070                                 target_ip->flags |= HAMMER_INODE_REFLUSH;
1071                         }
1072                 } else if (rec->type == HAMMER_MEM_RECORD_ADD) {
1073                         /*
1074                          * If the target IP is not flushing we can force
1075                          * it to flush, even if it is unable to write out
1076                          * any of its own records we have at least one in
1077                          * hand that we CAN deal with.
1078                          */
1079                         rec->flush_state = HAMMER_FST_FLUSH;
1080                         rec->flush_group = ip->flush_group;
1081                         hammer_ref(&rec->lock);
1082                         hammer_flush_inode_core(target_ip,
1083                                                 HAMMER_FLUSH_RECURSION);
1084                         r = 1;
1085                 } else {
1086                         /*
1087                          * General or delete-on-disk record.
1088                          *
1089                          * XXX this needs help.  If a delete-on-disk we could
1090                          * disconnect the target.  If the target has its own
1091                          * dependancies they really need to be flushed.
1092                          *
1093                          * XXX
1094                          */
1095                         rec->flush_state = HAMMER_FST_FLUSH;
1096                         rec->flush_group = ip->flush_group;
1097                         hammer_ref(&rec->lock);
1098                         hammer_flush_inode_core(target_ip,
1099                                                 HAMMER_FLUSH_RECURSION);
1100                         r = 1;
1101                 }
1102                 break;
1103         case HAMMER_FST_FLUSH:
1104                 /*
1105                  * Record already associated with a flush group.  It had
1106                  * better be ours.
1107                  */
1108                 KKASSERT(rec->flush_group == ip->flush_group);
1109                 r = 1;
1110                 break;
1111         }
1112         return(r);
1113 }
1114
1115 /*
1116  * Wait for a previously queued flush to complete
1117  */
1118 void
1119 hammer_wait_inode(hammer_inode_t ip)
1120 {
1121         while (ip->flush_state != HAMMER_FST_IDLE) {
1122                 ip->flags |= HAMMER_INODE_FLUSHW;
1123                 tsleep(&ip->flags, 0, "hmrwin", 0);
1124         }
1125 }
1126
1127 /*
1128  * Called by the backend code when a flush has been completed.
1129  * The inode has already been removed from the flush list.
1130  *
1131  * A pipelined flush can occur, in which case we must re-enter the
1132  * inode on the list and re-copy its fields.
1133  */
1134 void
1135 hammer_flush_inode_done(hammer_inode_t ip)
1136 {
1137         struct bio *bio;
1138         int dorel = 0;
1139
1140         KKASSERT(ip->flush_state == HAMMER_FST_FLUSH);
1141
1142         /*
1143          * Allow BIOs to queue to the inode's primary bioq again.
1144          */
1145         ip->flags &= ~HAMMER_INODE_WRITE_ALT;
1146
1147         /*
1148          * Merge left-over flags back into the frontend and fix the state.
1149          */
1150         ip->flags |= ip->sync_flags;
1151
1152         /*
1153          * The backend may have adjusted nlinks, so if the adjusted nlinks
1154          * does not match the fronttend set the frontend's RDIRTY flag again.
1155          */
1156         if (ip->ino_rec.ino_nlinks != ip->sync_ino_rec.ino_nlinks)
1157                 ip->flags |= HAMMER_INODE_RDIRTY;
1158
1159         /*
1160          * Reflush any BIOs that wound up in the alt list.  Our inode will
1161          * also wind up at the end of the flusher's list.
1162          */
1163         while ((bio = TAILQ_FIRST(&ip->bio_alt_list)) != NULL) {
1164                 TAILQ_REMOVE(&ip->bio_alt_list, bio, bio_act);
1165                 TAILQ_INSERT_TAIL(&ip->bio_list, bio, bio_act);
1166         }
1167         /*
1168          * Fix up the dirty buffer status.
1169          */
1170         if (TAILQ_FIRST(&ip->bio_list) ||
1171             (ip->vp && RB_ROOT(&ip->vp->v_rbdirty_tree))) {
1172                 ip->flags |= HAMMER_INODE_BUFS;
1173         }
1174
1175         /*
1176          * Re-set the XDIRTY flag if some of the inode's in-memory records
1177          * could not be flushed.
1178          */
1179         if (RB_ROOT(&ip->rec_tree))
1180                 ip->flags |= HAMMER_INODE_XDIRTY;
1181
1182         /*
1183          * Do not lose track of inodes which no longer have vnode
1184          * assocations, otherwise they may never get flushed again.
1185          */
1186         if ((ip->flags & HAMMER_INODE_MODMASK) && ip->vp == NULL)
1187                 ip->flags |= HAMMER_INODE_REFLUSH;
1188
1189         /*
1190          * Adjust flush_state.  The target state (idle or setup) shouldn't
1191          * be terribly important since we will reflush if we really need
1192          * to do anything. XXX
1193          */
1194         if (TAILQ_EMPTY(&ip->target_list) && RB_EMPTY(&ip->rec_tree)) {
1195                 ip->flush_state = HAMMER_FST_IDLE;
1196                 dorel = 1;
1197         } else {
1198                 ip->flush_state = HAMMER_FST_SETUP;
1199         }
1200
1201         /*
1202          * Clean up the vnode ref
1203          */
1204         if (ip->flags & HAMMER_INODE_VHELD) {
1205                 ip->flags &= ~HAMMER_INODE_VHELD;
1206                 vrele(ip->vp);
1207         }
1208
1209         /*
1210          * If the frontend made more changes and requested another flush,
1211          * then try to get it running.
1212          */
1213         if (ip->flags & HAMMER_INODE_REFLUSH) {
1214                 ip->flags &= ~HAMMER_INODE_REFLUSH;
1215                 if (ip->flags & HAMMER_INODE_RESIGNAL) {
1216                         ip->flags &= ~HAMMER_INODE_RESIGNAL;
1217                         hammer_flush_inode(ip, HAMMER_FLUSH_SIGNAL);
1218                 } else {
1219                         hammer_flush_inode(ip, 0);
1220                 }
1221         }
1222
1223         /*
1224          * Finally, if the frontend is waiting for a flush to complete,
1225          * wake it up.
1226          */
1227         if (ip->flush_state != HAMMER_FST_FLUSH) {
1228                 if (ip->flags & HAMMER_INODE_FLUSHW) {
1229                         ip->flags &= ~HAMMER_INODE_FLUSHW;
1230                         wakeup(&ip->flags);
1231                 }
1232         }
1233         if (dorel)
1234                 hammer_rel_inode(ip, 0);
1235 }
1236
1237 /*
1238  * Called from hammer_sync_inode() to synchronize in-memory records
1239  * to the media.
1240  */
1241 static int
1242 hammer_sync_record_callback(hammer_record_t record, void *data)
1243 {
1244         hammer_cursor_t cursor = data;
1245         hammer_transaction_t trans = cursor->trans;
1246         int error;
1247
1248         /*
1249          * Skip records that do not belong to the current flush.
1250          */
1251         if (record->flush_state != HAMMER_FST_FLUSH)
1252                 return(0);
1253         KKASSERT((record->flags & HAMMER_RECF_DELETED_BE) == 0);
1254 #if 1
1255         if (record->flush_group != record->ip->flush_group) {
1256                 kprintf("sync_record %p ip %p bad flush group %d %d\n", record, record->ip, record->flush_group ,record->ip->flush_group);
1257                 Debugger("blah2");
1258                 return(0);
1259         }
1260 #endif
1261         KKASSERT(record->flush_group == record->ip->flush_group);
1262
1263         /*
1264          * Interlock the record using the BE flag.  Once BE is set the
1265          * frontend cannot change the state of FE.
1266          *
1267          * NOTE: If FE is set prior to us setting BE we still sync the
1268          * record out, but the flush completion code converts it to
1269          * a delete-on-disk record instead of destroying it.
1270          */
1271         KKASSERT((record->flags & HAMMER_RECF_INTERLOCK_BE) == 0);
1272         record->flags |= HAMMER_RECF_INTERLOCK_BE;
1273
1274         /*
1275          * If DELETED_FE is set we may have already sent dependant pieces
1276          * to the disk and we must flush the record as if it hadn't been
1277          * deleted.  This creates a bit of a mess because we have to
1278          * have ip_sync_record convert the record to MEM_RECORD_DEL before
1279          * it inserts the B-Tree record.  Otherwise the media sync might
1280          * be visible to the frontend.
1281          */
1282         if (record->flags & HAMMER_RECF_DELETED_FE) {
1283                 if (record->type == HAMMER_MEM_RECORD_ADD) {
1284                         record->flags |= HAMMER_RECF_CONVERT_DELETE;
1285                 } else {
1286                         KKASSERT(record->type != HAMMER_MEM_RECORD_DEL);
1287                         return(0);
1288                 }
1289         }
1290
1291         /*
1292          * Assign the create_tid for new records.  Deletions already
1293          * have the record's entire key properly set up.
1294          */
1295         if (record->type != HAMMER_MEM_RECORD_DEL)
1296                 record->rec.inode.base.base.create_tid = trans->tid;
1297         for (;;) {
1298                 error = hammer_ip_sync_record_cursor(cursor, record);
1299                 if (error != EDEADLK)
1300                         break;
1301                 hammer_done_cursor(cursor);
1302                 error = hammer_init_cursor(trans, cursor, &record->ip->cache[0],
1303                                            record->ip);
1304                 if (error)
1305                         break;
1306         }
1307         record->flags &= ~HAMMER_RECF_CONVERT_DELETE;
1308
1309         if (error) {
1310                 error = -error;
1311                 if (error != -ENOSPC) {
1312                         kprintf("hammer_sync_record_callback: sync failed rec "
1313                                 "%p, error %d\n", record, error);
1314                         Debugger("sync failed rec");
1315                 }
1316         }
1317         hammer_flush_record_done(record, error);
1318         return(error);
1319 }
1320
1321 /*
1322  * XXX error handling
1323  */
1324 int
1325 hammer_sync_inode(hammer_inode_t ip)
1326 {
1327         struct hammer_transaction trans;
1328         struct hammer_cursor cursor;
1329         struct bio *bio;
1330         hammer_record_t depend;
1331         hammer_record_t next;
1332         int error, tmp_error;
1333         u_int64_t nlinks;
1334
1335         if ((ip->sync_flags & HAMMER_INODE_MODMASK) == 0)
1336                 return(0);
1337
1338         hammer_start_transaction_fls(&trans, ip->hmp);
1339         error = hammer_init_cursor(&trans, &cursor, &ip->cache[0], ip);
1340         if (error)
1341                 goto done;
1342
1343         /*
1344          * Any directory records referencing this inode which are not in
1345          * our current flush group must adjust our nlink count for the
1346          * purposes of synchronization to disk.
1347          *
1348          * Records which are in our flush group can be unlinked from our
1349          * inode now, allowing the inode to be physically deleted.
1350          */
1351         nlinks = ip->ino_rec.ino_nlinks;
1352         next = TAILQ_FIRST(&ip->target_list);
1353         while ((depend = next) != NULL) {
1354                 next = TAILQ_NEXT(depend, target_entry);
1355                 if (depend->flush_state == HAMMER_FST_FLUSH &&
1356                     depend->flush_group == ip->hmp->flusher_act) {
1357                         TAILQ_REMOVE(&ip->target_list, depend, target_entry);
1358                         depend->target_ip = NULL;
1359                         /* no need to signal target_ip, it is us */
1360                 } else if ((depend->flags & HAMMER_RECF_DELETED_FE) == 0) {
1361                         switch(depend->type) {
1362                         case HAMMER_MEM_RECORD_ADD:
1363                                 --nlinks;
1364                                 break;
1365                         case HAMMER_MEM_RECORD_DEL:
1366                                 ++nlinks;
1367                                 break;
1368                         default:
1369                                 break;
1370                         }
1371                 }
1372         }
1373
1374         /*
1375          * Set dirty if we had to modify the link count.
1376          */
1377         if (ip->sync_ino_rec.ino_nlinks != nlinks) {
1378                 KKASSERT((int64_t)nlinks >= 0);
1379                 ip->sync_ino_rec.ino_nlinks = nlinks;
1380                 ip->sync_flags |= HAMMER_INODE_RDIRTY;
1381         }
1382
1383         /*
1384          * Queue up as many dirty buffers as we can then set a flag to
1385          * cause any further BIOs to go to the alternative queue.
1386          */
1387         if (ip->flags & HAMMER_INODE_VHELD)
1388                 error = vfsync(ip->vp, MNT_NOWAIT, 1, NULL, NULL);
1389         ip->flags |= HAMMER_INODE_WRITE_ALT;
1390
1391         /*
1392          * The buffer cache may contain dirty buffers beyond the inode
1393          * state we copied from the frontend to the backend.  Because
1394          * we are syncing our buffer cache on the backend, resync
1395          * the truncation point and the file size so we don't wipe out
1396          * any data.
1397          *
1398          * Syncing the buffer cache on the frontend has serious problems
1399          * because it prevents us from passively queueing dirty inodes
1400          * to the backend (the BIO's could stall indefinitely).
1401          */
1402         if (ip->flags & HAMMER_INODE_TRUNCATED) {
1403                 ip->sync_trunc_off = ip->trunc_off;
1404                 ip->sync_flags |= HAMMER_INODE_TRUNCATED;
1405         }
1406         if (ip->sync_ino_rec.ino_size != ip->ino_rec.ino_size) {
1407                 ip->sync_ino_rec.ino_size = ip->ino_rec.ino_size;
1408                 ip->sync_flags |= HAMMER_INODE_RDIRTY;
1409         }
1410
1411         /*
1412          * If there is a trunction queued destroy any data past the (aligned)
1413          * truncation point.  Userland will have dealt with the buffer
1414          * containing the truncation point for us.
1415          *
1416          * We don't flush pending frontend data buffers until after we've
1417          * dealth with the truncation.
1418          *
1419          * Don't bother if the inode is or has been deleted.
1420          */
1421         if (ip->sync_flags & HAMMER_INODE_TRUNCATED) {
1422                 /*
1423                  * Interlock trunc_off.  The VOP front-end may continue to
1424                  * make adjustments to it while we are blocked.
1425                  */
1426                 off_t trunc_off;
1427                 off_t aligned_trunc_off;
1428
1429                 trunc_off = ip->sync_trunc_off;
1430                 aligned_trunc_off = (trunc_off + HAMMER_BUFMASK) &
1431                                     ~HAMMER_BUFMASK64;
1432
1433                 /*
1434                  * Delete any whole blocks on-media.  The front-end has
1435                  * already cleaned out any partial block and made it
1436                  * pending.  The front-end may have updated trunc_off
1437                  * while we were blocked so do not just unconditionally
1438                  * set it to the maximum offset.
1439                  */
1440                 error = hammer_ip_delete_range(&cursor, ip,
1441                                                 aligned_trunc_off,
1442                                                 0x7FFFFFFFFFFFFFFFLL);
1443                 if (error)
1444                         Debugger("hammer_ip_delete_range errored");
1445                 ip->sync_flags &= ~HAMMER_INODE_TRUNCATED;
1446                 if (ip->trunc_off >= trunc_off) {
1447                         ip->trunc_off = 0x7FFFFFFFFFFFFFFFLL;
1448                         ip->flags &= ~HAMMER_INODE_TRUNCATED;
1449                 }
1450         } else {
1451                 error = 0;
1452         }
1453
1454         /*
1455          * Now sync related records.  These will typically be directory
1456          * entries or delete-on-disk records.
1457          *
1458          * Not all records will be flushed, but clear XDIRTY anyway.  We
1459          * will set it again in the frontend hammer_flush_inode_done()
1460          * if records remain.
1461          */
1462         if (error == 0) {
1463                 tmp_error = RB_SCAN(hammer_rec_rb_tree, &ip->rec_tree, NULL,
1464                                     hammer_sync_record_callback, &cursor);
1465                 if (tmp_error < 0)
1466                         tmp_error = -error;
1467                 if (tmp_error)
1468                         error = tmp_error;
1469                 if (error == 0)
1470                         ip->sync_flags &= ~HAMMER_INODE_XDIRTY;
1471         }
1472
1473         /*
1474          * If we are deleting the inode the frontend had better not have
1475          * any active references on elements making up the inode.
1476          */
1477         if (error == 0 && ip->sync_ino_rec.ino_nlinks == 0 &&
1478                 RB_EMPTY(&ip->rec_tree)  &&
1479             (ip->sync_flags & HAMMER_INODE_DELETING) &&
1480             (ip->flags & HAMMER_INODE_DELETED) == 0) {
1481                 int count1 = 0;
1482
1483                 kprintf("Y");
1484                 ip->flags |= HAMMER_INODE_DELETED;
1485                 error = hammer_ip_delete_range_all(&cursor, ip, &count1);
1486                 if (error == 0) {
1487                         ip->sync_flags &= ~HAMMER_INODE_DELETING;
1488                         ip->sync_flags &= ~HAMMER_INODE_TRUNCATED;
1489                         KKASSERT(RB_EMPTY(&ip->rec_tree));
1490
1491                         /*
1492                          * Set delete_tid in both the frontend and backend
1493                          * copy of the inode record.  The DELETED flag handles
1494                          * this, do not set RDIRTY.
1495                          */
1496                         ip->ino_rec.base.base.delete_tid = trans.tid;
1497                         ip->sync_ino_rec.base.base.delete_tid = trans.tid;
1498
1499                         /*
1500                          * Adjust the inode count in the volume header
1501                          */
1502                         hammer_modify_volume_field(&trans, trans.rootvol,
1503                                                    vol0_stat_inodes);
1504                         --ip->hmp->rootvol->ondisk->vol0_stat_inodes;
1505                         hammer_modify_volume_done(trans.rootvol);
1506                 } else {
1507                         ip->flags &= ~HAMMER_INODE_DELETED;
1508                         Debugger("hammer_ip_delete_range_all errored");
1509                 }
1510         }
1511
1512         /*
1513          * Flush any queued BIOs.  These will just biodone() the IO's if
1514          * the inode has been deleted.
1515          */
1516         while ((bio = TAILQ_FIRST(&ip->bio_list)) != NULL) {
1517                 TAILQ_REMOVE(&ip->bio_list, bio, bio_act);
1518                 tmp_error = hammer_dowrite(&cursor, ip, bio);
1519                 if (tmp_error)
1520                         error = tmp_error;
1521         }
1522         ip->sync_flags &= ~HAMMER_INODE_BUFS;
1523
1524         if (error)
1525                 Debugger("RB_SCAN errored");
1526
1527         /*
1528          * Now update the inode's on-disk inode-data and/or on-disk record.
1529          * DELETED and ONDISK are managed only in ip->flags.
1530          */
1531         switch(ip->flags & (HAMMER_INODE_DELETED | HAMMER_INODE_ONDISK)) {
1532         case HAMMER_INODE_DELETED|HAMMER_INODE_ONDISK:
1533                 /*
1534                  * If deleted and on-disk, don't set any additional flags.
1535                  * the delete flag takes care of things.
1536                  *
1537                  * Clear flags which may have been set by the frontend.
1538                  */
1539                 ip->sync_flags &= ~(HAMMER_INODE_RDIRTY|HAMMER_INODE_DDIRTY|
1540                                     HAMMER_INODE_XDIRTY|HAMMER_INODE_ITIMES|
1541                                     HAMMER_INODE_DELETING);
1542                 break;
1543         case HAMMER_INODE_DELETED:
1544                 /*
1545                  * Take care of the case where a deleted inode was never
1546                  * flushed to the disk in the first place.
1547                  *
1548                  * Clear flags which may have been set by the frontend.
1549                  */
1550                 ip->sync_flags &= ~(HAMMER_INODE_RDIRTY|HAMMER_INODE_DDIRTY|
1551                                     HAMMER_INODE_XDIRTY|HAMMER_INODE_ITIMES|
1552                                     HAMMER_INODE_DELETING);
1553                 while (RB_ROOT(&ip->rec_tree)) {
1554                         hammer_record_t record = RB_ROOT(&ip->rec_tree);
1555                         hammer_ref(&record->lock);
1556                         KKASSERT(record->lock.refs == 1);
1557                         record->flags |= HAMMER_RECF_DELETED_FE;
1558                         record->flags |= HAMMER_RECF_DELETED_BE;
1559                         hammer_rel_mem_record(record);
1560                 }
1561                 break;
1562         case HAMMER_INODE_ONDISK:
1563                 /*
1564                  * If already on-disk, do not set any additional flags.
1565                  */
1566                 break;
1567         default:
1568                 /*
1569                  * If not on-disk and not deleted, set both dirty flags
1570                  * to force an initial record to be written.  Also set
1571                  * the create_tid for the inode.
1572                  *
1573                  * Set create_tid in both the frontend and backend
1574                  * copy of the inode record.
1575                  */
1576                 ip->ino_rec.base.base.create_tid = trans.tid;
1577                 ip->sync_ino_rec.base.base.create_tid = trans.tid;
1578                 ip->sync_flags |= HAMMER_INODE_RDIRTY | HAMMER_INODE_DDIRTY;
1579                 break;
1580         }
1581
1582         /*
1583          * If RDIRTY or DDIRTY is set, write out a new record.  If the inode
1584          * is already on-disk the old record is marked as deleted.
1585          *
1586          * If DELETED is set hammer_update_inode() will delete the existing
1587          * record without writing out a new one.
1588          *
1589          * If *ONLY* the ITIMES flag is set we can update the record in-place.
1590          */
1591         if (ip->flags & HAMMER_INODE_DELETED) {
1592                 error = hammer_update_inode(&cursor, ip);
1593         } else
1594         if ((ip->sync_flags & (HAMMER_INODE_RDIRTY | HAMMER_INODE_DDIRTY |
1595                                HAMMER_INODE_ITIMES)) == HAMMER_INODE_ITIMES) {
1596                 error = hammer_update_itimes(&cursor, ip);
1597         } else
1598         if (ip->sync_flags & (HAMMER_INODE_RDIRTY | HAMMER_INODE_DDIRTY |
1599                               HAMMER_INODE_ITIMES)) {
1600                 error = hammer_update_inode(&cursor, ip);
1601         }
1602         if (error)
1603                 Debugger("hammer_update_itimes/inode errored");
1604 done:
1605         /*
1606          * Save the TID we used to sync the inode with to make sure we
1607          * do not improperly reuse it.
1608          */
1609         hammer_done_cursor(&cursor);
1610         hammer_done_transaction(&trans);
1611         return(error);
1612 }
1613
1614 /*
1615  * This routine is called when the OS is no longer actively referencing
1616  * the inode (but might still be keeping it cached), or when releasing
1617  * the last reference to an inode.
1618  *
1619  * At this point if the inode's nlinks count is zero we want to destroy
1620  * it, which may mean destroying it on-media too.
1621  */
1622 void
1623 hammer_inode_unloadable_check(hammer_inode_t ip, int getvp)
1624 {
1625         struct vnode *vp;
1626
1627         /*
1628          * If the inode is on-media and the link count is 0 we MUST delete
1629          * it on-media.  DELETING is a mod flag, DELETED is a state flag.
1630          */
1631         if (ip->ino_rec.ino_nlinks == 0 &&
1632             (ip->flags & (HAMMER_INODE_DELETING|HAMMER_INODE_DELETED)) == 0) {
1633                 ip->flags |= HAMMER_INODE_DELETING;
1634                 ip->flags |= HAMMER_INODE_TRUNCATED;
1635                 ip->trunc_off = 0;
1636                 vp = NULL;
1637                 if (getvp) {
1638                         if (hammer_get_vnode(ip, &vp) != 0)
1639                                 return;
1640                 }
1641                 if (ip->vp) {
1642                         vtruncbuf(ip->vp, 0, HAMMER_BUFSIZE);
1643                         vnode_pager_setsize(ip->vp, 0);
1644                 }
1645                 if (getvp) {
1646                         vput(vp);
1647                 }
1648         }
1649 }
1650
1651 /*
1652  * Re-test an inode when a dependancy had gone away to see if we
1653  * can chain flush it.
1654  */
1655 void
1656 hammer_test_inode(hammer_inode_t ip)
1657 {
1658         if (ip->flags & HAMMER_INODE_REFLUSH) {
1659                 ip->flags &= ~HAMMER_INODE_REFLUSH;
1660                 hammer_ref(&ip->lock);
1661                 if (ip->flags & HAMMER_INODE_RESIGNAL) {
1662                         ip->flags &= ~HAMMER_INODE_RESIGNAL;
1663                         hammer_flush_inode(ip, HAMMER_FLUSH_SIGNAL);
1664                 } else {
1665                         hammer_flush_inode(ip, 0);
1666                 }
1667                 hammer_rel_inode(ip, 0);
1668         }
1669 }
1670