sys/ufs/chfs/chfs_nodeops.c

   1 /*      $NetBSD: chfs_nodeops.c,v 1.4 2013/12/09 09:35:17 wiz Exp $     */
   2
   3 /*-
   4  * Copyright (c) 2010 Department of Software Engineering,
   5  *                    University of Szeged, Hungary
   6  * Copyright (C) 2010 David Tengeri <dtengeri@inf.u-szeged.hu>
   7  * Copyright (C) 2010 Tamas Toth <ttoth@inf.u-szeged.hu>
   8  * Copyright (C) 2010 Adam Hoka <ahoka@NetBSD.org>
   9  * All rights reserved.
  10  *
  11  * This code is derived from software contributed to The NetBSD Foundation
  12  * by the Department of Software Engineering, University of Szeged, Hungary
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  26  * IN NO EVENT SHALL THE AUTHOR 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
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include "chfs.h"
  37
  38 /*
  39  * chfs_update_eb_dirty - updates dirty and free space, first and
  40  *                            last node references
  41  * Returns zero in case of success, 1 in case of fail.
  42  */
  43 int
  44 chfs_update_eb_dirty(struct chfs_mount *chmp,
  45     struct chfs_eraseblock *cheb, uint32_t size)
  46 {
  47         KASSERT(mutex_owned(&chmp->chm_lock_mountfields));
  48         KASSERT(!mutex_owned(&chmp->chm_lock_sizes));
  49
  50         if (!size)
  51                 return 0;
  52
  53         if (size > cheb->free_size) {
  54                 chfs_err("free_size (%d) is less than dirty space (%d) "
  55                     "on block (%d)\n", cheb->free_size, size, cheb->lnr);
  56                 return 1;
  57         }
  58         mutex_enter(&chmp->chm_lock_sizes);
  59         chfs_change_size_free(chmp, cheb, -size);
  60         chfs_change_size_dirty(chmp, cheb, size);
  61         mutex_exit(&chmp->chm_lock_sizes);
  62         return 0;
  63 }
  64
  65 /*
  66  * chfs_add_node_to_list - adds a data node ref to vnode cache's dnode list
  67  * This function inserts a data node ref to the list of vnode cache.
  68  * The list is sorted by data node's lnr and offset.
  69  */
  70 void
  71 chfs_add_node_to_list(struct chfs_mount *chmp,
  72     struct chfs_vnode_cache *vc,
  73     struct chfs_node_ref *new, struct chfs_node_ref **list)
  74 {
  75         KASSERT(mutex_owned(&chmp->chm_lock_vnocache));
  76
  77         struct chfs_node_ref *nextref = *list;
  78         struct chfs_node_ref *prevref = NULL;
  79
  80         while (nextref && nextref != (struct chfs_node_ref *)vc &&
  81             (nextref->nref_lnr <= new->nref_lnr)) {
  82                 if (nextref->nref_lnr == new->nref_lnr) {
  83                         while (nextref && nextref !=
  84                             (struct chfs_node_ref *)vc &&
  85                             (CHFS_GET_OFS(nextref->nref_offset) <
  86                                 CHFS_GET_OFS(new->nref_offset))) {
  87                                 prevref = nextref;
  88                                 nextref = nextref->nref_next;
  89                         }
  90                         break;
  91                 }
  92                 prevref = nextref;
  93                 nextref = nextref->nref_next;
  94         }
  95
  96         if (nextref && nextref != (struct chfs_node_ref *)vc &&
  97             nextref->nref_lnr == new->nref_lnr &&
  98             CHFS_GET_OFS(nextref->nref_offset) ==
  99             CHFS_GET_OFS(new->nref_offset)) {
 100                 new->nref_next = nextref->nref_next;
 101                 chfs_mark_node_obsolete(chmp, nextref);
 102         } else {
 103                 new->nref_next = nextref;
 104         }
 105
 106         KASSERT(new->nref_next != NULL);
 107
 108         if (prevref) {
 109                 prevref->nref_next = new;
 110         } else {
 111                 *list = new;
 112         }
 113 }
 114
 115 /*
 116  * chfs_remove_node_from_list - removes a node from a list
 117  * Usually used for removing data nodes.
 118  */
 119 void
 120 chfs_remove_node_from_list(struct chfs_mount *chmp,
 121         struct chfs_vnode_cache *vc,
 122         struct chfs_node_ref *old_nref, struct chfs_node_ref **list)
 123 {
 124         KASSERT(mutex_owned(&chmp->chm_lock_mountfields));
 125         KASSERT(mutex_owned(&chmp->chm_lock_vnocache));
 126
 127         struct chfs_node_ref *tmpnref;
 128
 129         if (*list == (struct chfs_node_ref *)vc) {
 130                 /* list is empty */
 131                 return;
 132         }
 133
 134         KASSERT(old_nref->nref_next != NULL);
 135
 136         if (*list == old_nref) {
 137                 *list = old_nref->nref_next;
 138         } else {
 139                 tmpnref = *list;
 140                 while (tmpnref->nref_next &&
 141                         tmpnref->nref_next != (struct chfs_node_ref *)vc) {
 142                         if (tmpnref->nref_next == old_nref) {
 143                                 tmpnref->nref_next = old_nref->nref_next;
 144                                 break;
 145                         }
 146                         tmpnref = tmpnref->nref_next;
 147                 }
 148         }
 149 }
 150
 151 /*
 152  * chfs_remove_and_obsolete - removes a node from a list and obsoletes the nref
 153  * We should use this function carefully on data nodes,
 154  * because removing a frag will also obsolete the node ref.
 155  */
 156 void
 157 chfs_remove_and_obsolete(struct chfs_mount *chmp,
 158         struct chfs_vnode_cache *vc,
 159         struct chfs_node_ref *old_nref, struct chfs_node_ref **list)
 160 {
 161         KASSERT(mutex_owned(&chmp->chm_lock_mountfields));
 162         KASSERT(mutex_owned(&chmp->chm_lock_vnocache));
 163
 164         chfs_remove_node_from_list(chmp, vc, old_nref, list);
 165
 166         dbg("[MARK] vno: %llu lnr: %u ofs: %u\n", vc->vno, old_nref->nref_lnr,
 167                 old_nref->nref_offset);
 168         chfs_mark_node_obsolete(chmp, old_nref);
 169 }
 170
 171 /* chfs_add_fd_to_inode - adds a directory entry to an inode */
 172 void
 173 chfs_add_fd_to_inode(struct chfs_mount *chmp,
 174     struct chfs_inode *parent, struct chfs_dirent *new)
 175 {
 176         struct chfs_dirent *fd, *tmpfd;
 177
 178         /* update highest version */
 179         if (new->version > parent->chvc->highest_version) {
 180                 parent->chvc->highest_version = new->version;
 181         }
 182
 183         TAILQ_FOREACH_SAFE(fd, &parent->dents, fds, tmpfd) {
 184                 if (fd->nhash > new->nhash) {
 185                         /* insert new before fd */
 186                         TAILQ_INSERT_BEFORE(fd, new, fds);
 187                         return;
 188                 } else if (fd->nhash == new->nhash &&
 189                     !strcmp(fd->name, new->name)) {
 190                         if (new->version > fd->version) {
 191                                 /* replace fd with new */
 192                                 TAILQ_INSERT_BEFORE(fd, new, fds);
 193                                 TAILQ_REMOVE(&parent->dents, fd, fds);
 194                                 if (fd->nref) {
 195                                         mutex_enter(&chmp->chm_lock_vnocache);
 196                                         chfs_remove_and_obsolete(chmp, parent->chvc, fd->nref,
 197                                                 &parent->chvc->dirents);
 198                                         mutex_exit(&chmp->chm_lock_vnocache);
 199                                 }
 200                                 chfs_free_dirent(fd);
 201                         } else {
 202                                 /* new is older (normally it's not an option) */
 203                                 chfs_mark_node_obsolete(chmp, new->nref);
 204                                 chfs_free_dirent(new);
 205                         }
 206                         return;
 207                 }
 208         }
 209         /* if we couldnt fit it elsewhere, lets add to the end */
 210         /* FIXME insert tail or insert head? */
 211         TAILQ_INSERT_HEAD(&parent->dents, new, fds);
 212 }
 213
 214
 215 /* chfs_add_vnode_ref_to_vc - adds a vnode info to the vnode cache */
 216 void
 217 chfs_add_vnode_ref_to_vc(struct chfs_mount *chmp,
 218     struct chfs_vnode_cache *vc, struct chfs_node_ref *new)
 219 {
 220         KASSERT(mutex_owned(&chmp->chm_lock_vnocache));
 221         struct chfs_node_ref *nref;
 222
 223         /* store only the last one, drop the others */
 224         while (vc->v != (struct chfs_node_ref *)vc) {
 225                 nref = vc->v;
 226                 chfs_remove_and_obsolete(chmp, vc, nref, &vc->v);
 227         }
 228
 229         new->nref_next = (struct chfs_node_ref *)vc;
 230         vc->v = new;
 231 }
 232
 233 /* chfs_nref_next - step to the next in-memory nref */
 234 struct chfs_node_ref *
 235 chfs_nref_next(struct chfs_node_ref *nref)
 236 {
 237         nref++;
 238         if (nref->nref_lnr == REF_LINK_TO_NEXT) {
 239                 /* end of chain */
 240                 if (!nref->nref_next)
 241                         return NULL;
 242
 243                 /* link to the next block */
 244                 nref = nref->nref_next;
 245         }
 246         /* end of chain */
 247         if (nref->nref_lnr == REF_EMPTY_NODE)
 248                 return NULL;
 249
 250         return nref;
 251 }
 252
 253 /* chfs_nref_len - calculates the length of an nref */
 254 int
 255 chfs_nref_len(struct chfs_mount *chmp,
 256     struct chfs_eraseblock *cheb, struct chfs_node_ref *nref)
 257 {
 258         struct chfs_node_ref *next;
 259
 260         KASSERT(mutex_owned(&chmp->chm_lock_mountfields));
 261
 262         if (!cheb)
 263                 cheb = &chmp->chm_blocks[nref->nref_lnr];
 264
 265         next = chfs_nref_next(nref);
 266
 267         if (!next) {
 268                 return chmp->chm_ebh->eb_size - cheb->free_size -
 269                     CHFS_GET_OFS(nref->nref_offset);
 270         }
 271         return CHFS_GET_OFS(next->nref_offset) -
 272             CHFS_GET_OFS(nref->nref_offset);
 273 }
 274
 275 /* chfs_mark_node_obsolete - marks a node as obsolete */
 276 void
 277 chfs_mark_node_obsolete(struct chfs_mount *chmp,
 278     struct chfs_node_ref *nref)
 279 {
 280         int len;
 281         struct chfs_eraseblock *cheb;
 282
 283         KASSERT(mutex_owned(&chmp->chm_lock_mountfields));
 284
 285         KASSERT(!CHFS_REF_OBSOLETE(nref));
 286
 287         KASSERT(nref->nref_lnr <= chmp->chm_ebh->peb_nr);
 288         cheb = &chmp->chm_blocks[nref->nref_lnr];
 289
 290 #ifdef DIAGNOSTIC
 291         if (cheb->used_size + cheb->free_size + cheb->dirty_size +
 292             cheb->unchecked_size + cheb->wasted_size != chmp->chm_ebh->eb_size) {
 293                 dbg("eraseblock leak detected!\nused: %u\nfree: %u\n"
 294                     "dirty: %u\nunchecked: %u\nwasted: %u\ntotal: %u\nshould be: %zu\n",
 295                     cheb->used_size, cheb->free_size, cheb->dirty_size,
 296                     cheb->unchecked_size, cheb->wasted_size, cheb->used_size + cheb->free_size +
 297                     cheb->dirty_size + cheb->unchecked_size + cheb->wasted_size,
 298                     chmp->chm_ebh->eb_size);
 299         }
 300 #endif
 301
 302         len = chfs_nref_len(chmp, cheb, nref);
 303
 304         mutex_enter(&chmp->chm_lock_sizes);
 305
 306         if (CHFS_REF_FLAGS(nref) == CHFS_UNCHECKED_NODE_MASK) {
 307                 chfs_change_size_unchecked(chmp, cheb, -len);
 308         } else {
 309                 chfs_change_size_used(chmp, cheb, -len);
 310
 311                 KASSERT(cheb->used_size <= chmp->chm_ebh->eb_size);
 312         }
 313         chfs_change_size_dirty(chmp, cheb, len);
 314
 315 #ifdef DIAGNOSTIC
 316         if (cheb->used_size + cheb->free_size + cheb->dirty_size +
 317             cheb->unchecked_size + cheb->wasted_size != chmp->chm_ebh->eb_size) {
 318                 panic("eraseblock leak detected!\nused: %u\nfree: %u\n"
 319                     "dirty: %u\nunchecked: %u\nwasted: %u\ntotal: %u\nshould be: %zu\n",
 320                     cheb->used_size, cheb->free_size, cheb->dirty_size,
 321                     cheb->unchecked_size, cheb->wasted_size, cheb->used_size + cheb->free_size +
 322                     cheb->dirty_size + cheb->unchecked_size + cheb->wasted_size,
 323                     chmp->chm_ebh->eb_size);
 324         }
 325 #endif
 326         nref->nref_offset = CHFS_GET_OFS(nref->nref_offset) |
 327             CHFS_OBSOLETE_NODE_MASK;
 328
 329         if (chmp->chm_flags & CHFS_MP_FLAG_SCANNING) {
 330                 /*Scan is in progress, do nothing now*/
 331                 mutex_exit(&chmp->chm_lock_sizes);
 332                 return;
 333         }
 334
 335         if (cheb == chmp->chm_nextblock) {
 336                 dbg("Not moving nextblock to dirty/erase_pending list\n");
 337         } else if (!cheb->used_size && !cheb->unchecked_size) {
 338                 if (cheb == chmp->chm_gcblock) {
 339                         dbg("gcblock is completely dirtied\n");
 340                         chmp->chm_gcblock = NULL;
 341                 } else {
 342                         /* remove from a tailq, but we don't know which tailq contains this cheb
 343                          * so we remove it from the dirty list now */
 344                         //TAILQ_REMOVE(&chmp->chm_dirty_queue, cheb, queue);
 345                         int removed = 0;
 346                         struct chfs_eraseblock *eb, *tmpeb;
 347                         //XXX ugly code
 348                         TAILQ_FOREACH_SAFE(eb, &chmp->chm_free_queue, queue, tmpeb) {
 349                                 if (eb == cheb) {
 350                                         TAILQ_REMOVE(&chmp->chm_free_queue, cheb, queue);
 351                                         removed = 1;
 352                                         break;
 353                                 }
 354                         }
 355                         if (removed == 0) {
 356                                 TAILQ_FOREACH_SAFE(eb, &chmp->chm_dirty_queue, queue, tmpeb) {
 357                                         if (eb == cheb) {
 358                                                 TAILQ_REMOVE(&chmp->chm_dirty_queue, cheb, queue);
 359                                                 removed = 1;
 360                                                 break;
 361                                         }
 362                                 }
 363                         }
 364                         if (removed == 0) {
 365                                 TAILQ_FOREACH_SAFE(eb, &chmp->chm_very_dirty_queue, queue, tmpeb) {
 366                                         if (eb == cheb) {
 367                                                 TAILQ_REMOVE(&chmp->chm_very_dirty_queue, cheb, queue);
 368                                                 removed = 1;
 369                                                 break;
 370                                         }
 371                                 }
 372                         }
 373                         if (removed == 0) {
 374                                 TAILQ_FOREACH_SAFE(eb, &chmp->chm_clean_queue, queue, tmpeb) {
 375                                         if (eb == cheb) {
 376                                                 TAILQ_REMOVE(&chmp->chm_clean_queue, cheb, queue);
 377                                                 removed = 1;
 378                                                 break;
 379                                         }
 380                                 }
 381                         }
 382                 }
 383                 if (chmp->chm_wbuf_len) {
 384                         dbg("Adding block to erasable pending wbuf queue\n");
 385                         TAILQ_INSERT_TAIL(&chmp->chm_erasable_pending_wbuf_queue,
 386                             cheb, queue);
 387                 } else {
 388                         TAILQ_INSERT_TAIL(&chmp->chm_erase_pending_queue,
 389                             cheb, queue);
 390                         chmp->chm_nr_erasable_blocks++;
 391                 }
 392                 chfs_remap_leb(chmp);
 393         } else if (cheb == chmp->chm_gcblock) {
 394                 dbg("Not moving gcblock to dirty list\n");
 395         } else if (cheb->dirty_size > MAX_DIRTY_TO_CLEAN &&
 396             cheb->dirty_size - len <= MAX_DIRTY_TO_CLEAN) {
 397                 dbg("Freshly dirtied, remove it from clean queue and "
 398                     "add it to dirty\n");
 399                 TAILQ_REMOVE(&chmp->chm_clean_queue, cheb, queue);
 400                 TAILQ_INSERT_TAIL(&chmp->chm_dirty_queue, cheb, queue);
 401         } else if (VERY_DIRTY(chmp, cheb->dirty_size) &&
 402             !VERY_DIRTY(chmp, cheb->dirty_size - len)) {
 403                 dbg("Becomes now very dirty, remove it from dirty "
 404                     "queue and add it to very dirty\n");
 405                 TAILQ_REMOVE(&chmp->chm_dirty_queue, cheb, queue);
 406                 TAILQ_INSERT_TAIL(&chmp->chm_very_dirty_queue, cheb, queue);
 407         } else {
 408                 dbg("Leave cheb where it is\n");
 409         }
 410         mutex_exit(&chmp->chm_lock_sizes);
 411         return;
 412 }
 413
 414 /*
 415  * chfs_close_eraseblock - close an eraseblock
 416  *
 417  * This function close the physical chain of the nodes on the eraseblock,
 418  * convert its free size to dirty and add it to clean, dirty or very dirty list.
 419  */
 420 int
 421 chfs_close_eraseblock(struct chfs_mount *chmp,
 422     struct chfs_eraseblock *cheb)
 423 {
 424         uint32_t offset;
 425         struct chfs_node_ref *nref;
 426
 427         KASSERT(mutex_owned(&chmp->chm_lock_mountfields));
 428
 429         offset = chmp->chm_ebh->eb_size - cheb->free_size;
 430
 431         // Close the chain
 432         nref = chfs_alloc_node_ref(cheb);
 433         if (!nref)
 434                 return ENOMEM;
 435
 436         nref->nref_next = NULL;
 437         nref->nref_offset = offset;
 438
 439         // Mark space as dirty
 440         chfs_update_eb_dirty(chmp, cheb, cheb->free_size);
 441
 442         if (cheb->dirty_size < MAX_DIRTY_TO_CLEAN) {
 443                 TAILQ_INSERT_TAIL(&chmp->chm_clean_queue, cheb, queue);
 444         } else if (VERY_DIRTY(chmp, cheb->dirty_size)) {
 445                 TAILQ_INSERT_TAIL(&chmp->chm_very_dirty_queue, cheb, queue);
 446         } else {
 447                 TAILQ_INSERT_TAIL(&chmp->chm_dirty_queue, cheb, queue);
 448         }
 449         return 0;
 450 }
 451
 452 /*
 453  * chfs_reserve_space_normal -
 454  * checks available space and calls chfs_reserve_space
 455  * used during writing
 456  */
 457 int
 458 chfs_reserve_space_normal(struct chfs_mount *chmp, uint32_t size, int prio)
 459 {
 460         int ret;
 461
 462         KASSERT(mutex_owned(&chmp->chm_lock_mountfields));
 463
 464         mutex_enter(&chmp->chm_lock_sizes);
 465         while (chmp->chm_nr_free_blocks + chmp->chm_nr_erasable_blocks < chmp->chm_resv_blocks_write) {
 466                 dbg("free: %d, erasable: %d, resv: %d\n", chmp->chm_nr_free_blocks, chmp->chm_nr_erasable_blocks, chmp->chm_resv_blocks_write);
 467                 uint32_t avail, dirty;
 468                 if (prio == ALLOC_DELETION && chmp->chm_nr_free_blocks + chmp->chm_nr_erasable_blocks >= chmp->chm_resv_blocks_deletion)
 469                         break;
 470
 471                 dirty = chmp->chm_dirty_size - chmp->chm_nr_erasable_blocks * chmp->chm_ebh->eb_size + chmp->chm_unchecked_size;
 472                 if (dirty < chmp->chm_nospc_dirty) {
 473                         dbg("dirty: %u < nospc_dirty: %u\n", dirty, chmp->chm_nospc_dirty);
 474                         ret = ENOSPC;
 475                         mutex_exit(&chmp->chm_lock_sizes);
 476                         goto out;
 477                 }
 478
 479                 avail = chmp->chm_free_size - (chmp->chm_resv_blocks_write * chmp->chm_ebh->eb_size);
 480                 if (size > avail) {
 481                         dbg("size: %u > avail: %u\n", size, avail);
 482                         ret = ENOSPC;
 483                         mutex_exit(&chmp->chm_lock_sizes);
 484                         goto out;
 485                 }
 486
 487                 mutex_exit(&chmp->chm_lock_sizes);
 488                 ret = chfs_gcollect_pass(chmp);
 489                 mutex_enter(&chmp->chm_lock_sizes);
 490
 491                 if (chmp->chm_nr_erasable_blocks ||
 492                     !TAILQ_EMPTY(&chmp->chm_erasable_pending_wbuf_queue) ||
 493                     ret == EAGAIN) {
 494                         ret = chfs_remap_leb(chmp);
 495                 }
 496
 497                 if (ret) {
 498                         mutex_exit(&chmp->chm_lock_sizes);
 499                         goto out;
 500                 }
 501         }
 502
 503         mutex_exit(&chmp->chm_lock_sizes);
 504         ret = chfs_reserve_space(chmp, size);
 505 out:
 506         return ret;
 507 }
 508
 509
 510 /* chfs_reserve_space_gc - tries to reserve space for GC */
 511 int
 512 chfs_reserve_space_gc(struct chfs_mount *chmp, uint32_t size)
 513 {
 514         int ret;
 515
 516         KASSERT(mutex_owned(&chmp->chm_lock_mountfields));
 517
 518         mutex_enter(&chmp->chm_lock_sizes);
 519         chfs_remap_leb(chmp);
 520
 521         if (size > chmp->chm_free_size) {
 522                 dbg("size: %u\n", size);
 523                 mutex_exit(&chmp->chm_lock_sizes);
 524                 return ENOSPC;
 525         }
 526
 527         mutex_exit(&chmp->chm_lock_sizes);
 528         ret = chfs_reserve_space(chmp, size);
 529         return ret;
 530 }
 531
 532 /*
 533  * chfs_reserve_space - finds a block which free size is >= requested size
 534  * Returns zero in case of success, error code in case of fail.
 535  */
 536 int
 537 chfs_reserve_space(struct chfs_mount *chmp, uint32_t size)
 538 {
 539         //TODO define minimum reserved blocks, which is needed for writing
 540         //TODO check we have enough free blocks to write
 541         //TODO if no: need erase and GC
 542
 543         int err;
 544         struct chfs_eraseblock *cheb;
 545
 546         KASSERT(mutex_owned(&chmp->chm_lock_mountfields));
 547         KASSERT(!mutex_owned(&chmp->chm_lock_sizes));
 548
 549         cheb = chmp->chm_nextblock;
 550         if (cheb && size > cheb->free_size) {
 551                 dbg("size: %u > free_size: %u\n", size, cheb->free_size);
 552                 /*
 553                  * There isn't enough space on this eraseblock, we mark this as
 554                  * dirty and close the physical chain of the node refs.
 555                  */
 556                 //Write out pending data if any
 557                 if (chmp->chm_wbuf_len) {
 558                         chfs_flush_pending_wbuf(chmp);
 559                         //FIXME need goto restart here?
 560                 }
 561
 562                 while (chmp->chm_wbuf_ofs < chmp->chm_ebh->eb_size) {
 563                         dbg("wbuf ofs: %zu - eb_size: %zu\n",
 564                             chmp->chm_wbuf_ofs, chmp->chm_ebh->eb_size);
 565                         chfs_flush_pending_wbuf(chmp);
 566                 }
 567
 568                 if (!(chmp->chm_wbuf_ofs % chmp->chm_ebh->eb_size) && !chmp->chm_wbuf_len)
 569                         chmp->chm_wbuf_ofs = 0xffffffff;
 570
 571                 err = chfs_close_eraseblock(chmp, cheb);
 572                 if (err)
 573                         return err;
 574
 575                 cheb = NULL;
 576         }
 577         if (!cheb) {
 578                 //get a block for nextblock
 579                 if (TAILQ_EMPTY(&chmp->chm_free_queue)) {
 580                         // If this succeeds there will be a block on free_queue
 581                         dbg("cheb remap (free: %d)\n", chmp->chm_nr_free_blocks);
 582                         err = chfs_remap_leb(chmp);
 583                         if (err)
 584                                 return err;
 585                 }
 586                 cheb = TAILQ_FIRST(&chmp->chm_free_queue);
 587                 TAILQ_REMOVE(&chmp->chm_free_queue, cheb, queue);
 588                 chmp->chm_nextblock = cheb;
 589                 chmp->chm_nr_free_blocks--;
 590         }
 591
 592         return 0;
 593 }
 594