fs/ocfs2/alloc.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * alloc.c
   5  *
   6  * Extent allocs and frees
   7  *
   8  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2 of the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public
  21  * License along with this program; if not, write to the
  22  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23  * Boston, MA 021110-1307, USA.
  24  */
  25
  26 #include <linux/fs.h>
  27 #include <linux/types.h>
  28 #include <linux/slab.h>
  29 #include <linux/highmem.h>
  30
  31 #define MLOG_MASK_PREFIX ML_DISK_ALLOC
  32 #include <cluster/masklog.h>
  33
  34 #include "ocfs2.h"
  35
  36 #include "alloc.h"
  37 #include "dlmglue.h"
  38 #include "extent_map.h"
  39 #include "inode.h"
  40 #include "journal.h"
  41 #include "localalloc.h"
  42 #include "suballoc.h"
  43 #include "sysfile.h"
  44 #include "file.h"
  45 #include "super.h"
  46 #include "uptodate.h"
  47
  48 #include "buffer_head_io.h"
  49
  50 static int ocfs2_extent_contig(struct inode *inode,
  51                                struct ocfs2_extent_rec *ext,
  52                                u64 blkno);
  53
  54 static int ocfs2_create_new_meta_bhs(struct ocfs2_super *osb,
  55                                      handle_t *handle,
  56                                      struct inode *inode,
  57                                      int wanted,
  58                                      struct ocfs2_alloc_context *meta_ac,
  59                                      struct buffer_head *bhs[]);
  60
  61 static int ocfs2_add_branch(struct ocfs2_super *osb,
  62                             handle_t *handle,
  63                             struct inode *inode,
  64                             struct buffer_head *fe_bh,
  65                             struct buffer_head *eb_bh,
  66                             struct buffer_head *last_eb_bh,
  67                             struct ocfs2_alloc_context *meta_ac);
  68
  69 static int ocfs2_shift_tree_depth(struct ocfs2_super *osb,
  70                                   handle_t *handle,
  71                                   struct inode *inode,
  72                                   struct buffer_head *fe_bh,
  73                                   struct ocfs2_alloc_context *meta_ac,
  74                                   struct buffer_head **ret_new_eb_bh);
  75
  76 static int ocfs2_do_insert_extent(struct ocfs2_super *osb,
  77                                   handle_t *handle,
  78                                   struct inode *inode,
  79                                   struct buffer_head *fe_bh,
  80                                   u64 blkno,
  81                                   u32 new_clusters);
  82
  83 static int ocfs2_find_branch_target(struct ocfs2_super *osb,
  84                                     struct inode *inode,
  85                                     struct buffer_head *fe_bh,
  86                                     struct buffer_head **target_bh);
  87
  88 static int ocfs2_find_new_last_ext_blk(struct ocfs2_super *osb,
  89                                        struct inode *inode,
  90                                        struct ocfs2_dinode *fe,
  91                                        unsigned int new_i_clusters,
  92                                        struct buffer_head *old_last_eb,
  93                                        struct buffer_head **new_last_eb);
  94
  95 static void ocfs2_free_truncate_context(struct ocfs2_truncate_context *tc);
  96
  97 static int ocfs2_extent_contig(struct inode *inode,
  98                                struct ocfs2_extent_rec *ext,
  99                                u64 blkno)
 100 {
 101         return blkno == (le64_to_cpu(ext->e_blkno) +
 102                          ocfs2_clusters_to_blocks(inode->i_sb,
 103                                                   le32_to_cpu(ext->e_clusters)));
 104 }
 105
 106 /*
 107  * How many free extents have we got before we need more meta data?
 108  */
 109 int ocfs2_num_free_extents(struct ocfs2_super *osb,
 110                            struct inode *inode,
 111                            struct ocfs2_dinode *fe)
 112 {
 113         int retval;
 114         struct ocfs2_extent_list *el;
 115         struct ocfs2_extent_block *eb;
 116         struct buffer_head *eb_bh = NULL;
 117
 118         mlog_entry_void();
 119
 120         if (!OCFS2_IS_VALID_DINODE(fe)) {
 121                 OCFS2_RO_ON_INVALID_DINODE(inode->i_sb, fe);
 122                 retval = -EIO;
 123                 goto bail;
 124         }
 125
 126         if (fe->i_last_eb_blk) {
 127                 retval = ocfs2_read_block(osb, le64_to_cpu(fe->i_last_eb_blk),
 128                                           &eb_bh, OCFS2_BH_CACHED, inode);
 129                 if (retval < 0) {
 130                         mlog_errno(retval);
 131                         goto bail;
 132                 }
 133                 eb = (struct ocfs2_extent_block *) eb_bh->b_data;
 134                 el = &eb->h_list;
 135         } else
 136                 el = &fe->id2.i_list;
 137
 138         BUG_ON(el->l_tree_depth != 0);
 139
 140         retval = le16_to_cpu(el->l_count) - le16_to_cpu(el->l_next_free_rec);
 141 bail:
 142         if (eb_bh)
 143                 brelse(eb_bh);
 144
 145         mlog_exit(retval);
 146         return retval;
 147 }
 148
 149 /* expects array to already be allocated
 150  *
 151  * sets h_signature, h_blkno, h_suballoc_bit, h_suballoc_slot, and
 152  * l_count for you
 153  */
 154 static int ocfs2_create_new_meta_bhs(struct ocfs2_super *osb,
 155                                      handle_t *handle,
 156                                      struct inode *inode,
 157                                      int wanted,
 158                                      struct ocfs2_alloc_context *meta_ac,
 159                                      struct buffer_head *bhs[])
 160 {
 161         int count, status, i;
 162         u16 suballoc_bit_start;
 163         u32 num_got;
 164         u64 first_blkno;
 165         struct ocfs2_extent_block *eb;
 166
 167         mlog_entry_void();
 168
 169         count = 0;
 170         while (count < wanted) {
 171                 status = ocfs2_claim_metadata(osb,
 172                                               handle,
 173                                               meta_ac,
 174                                               wanted - count,
 175                                               &suballoc_bit_start,
 176                                               &num_got,
 177                                               &first_blkno);
 178                 if (status < 0) {
 179                         mlog_errno(status);
 180                         goto bail;
 181                 }
 182
 183                 for(i = count;  i < (num_got + count); i++) {
 184                         bhs[i] = sb_getblk(osb->sb, first_blkno);
 185                         if (bhs[i] == NULL) {
 186                                 status = -EIO;
 187                                 mlog_errno(status);
 188                                 goto bail;
 189                         }
 190                         ocfs2_set_new_buffer_uptodate(inode, bhs[i]);
 191
 192                         status = ocfs2_journal_access(handle, inode, bhs[i],
 193                                                       OCFS2_JOURNAL_ACCESS_CREATE);
 194                         if (status < 0) {
 195                                 mlog_errno(status);
 196                                 goto bail;
 197                         }
 198
 199                         memset(bhs[i]->b_data, 0, osb->sb->s_blocksize);
 200                         eb = (struct ocfs2_extent_block *) bhs[i]->b_data;
 201                         /* Ok, setup the minimal stuff here. */
 202                         strcpy(eb->h_signature, OCFS2_EXTENT_BLOCK_SIGNATURE);
 203                         eb->h_blkno = cpu_to_le64(first_blkno);
 204                         eb->h_fs_generation = cpu_to_le32(osb->fs_generation);
 205
 206 #ifndef OCFS2_USE_ALL_METADATA_SUBALLOCATORS
 207                         /* we always use slot zero's suballocator */
 208                         eb->h_suballoc_slot = 0;
 209 #else
 210                         eb->h_suballoc_slot = cpu_to_le16(osb->slot_num);
 211 #endif
 212                         eb->h_suballoc_bit = cpu_to_le16(suballoc_bit_start);
 213                         eb->h_list.l_count =
 214                                 cpu_to_le16(ocfs2_extent_recs_per_eb(osb->sb));
 215
 216                         suballoc_bit_start++;
 217                         first_blkno++;
 218
 219                         /* We'll also be dirtied by the caller, so
 220                          * this isn't absolutely necessary. */
 221                         status = ocfs2_journal_dirty(handle, bhs[i]);
 222                         if (status < 0) {
 223                                 mlog_errno(status);
 224                                 goto bail;
 225                         }
 226                 }
 227
 228                 count += num_got;
 229         }
 230
 231         status = 0;
 232 bail:
 233         if (status < 0) {
 234                 for(i = 0; i < wanted; i++) {
 235                         if (bhs[i])
 236                                 brelse(bhs[i]);
 237                         bhs[i] = NULL;
 238                 }
 239         }
 240         mlog_exit(status);
 241         return status;
 242 }
 243
 244 /*
 245  * Add an entire tree branch to our inode. eb_bh is the extent block
 246  * to start at, if we don't want to start the branch at the dinode
 247  * structure.
 248  *
 249  * last_eb_bh is required as we have to update it's next_leaf pointer
 250  * for the new last extent block.
 251  *
 252  * the new branch will be 'empty' in the sense that every block will
 253  * contain a single record with e_clusters == 0.
 254  */
 255 static int ocfs2_add_branch(struct ocfs2_super *osb,
 256                             handle_t *handle,
 257                             struct inode *inode,
 258                             struct buffer_head *fe_bh,
 259                             struct buffer_head *eb_bh,
 260                             struct buffer_head *last_eb_bh,
 261                             struct ocfs2_alloc_context *meta_ac)
 262 {
 263         int status, new_blocks, i;
 264         u64 next_blkno, new_last_eb_blk;
 265         struct buffer_head *bh;
 266         struct buffer_head **new_eb_bhs = NULL;
 267         struct ocfs2_dinode *fe;
 268         struct ocfs2_extent_block *eb;
 269         struct ocfs2_extent_list  *eb_el;
 270         struct ocfs2_extent_list  *el;
 271
 272         mlog_entry_void();
 273
 274         BUG_ON(!last_eb_bh);
 275
 276         fe = (struct ocfs2_dinode *) fe_bh->b_data;
 277
 278         if (eb_bh) {
 279                 eb = (struct ocfs2_extent_block *) eb_bh->b_data;
 280                 el = &eb->h_list;
 281         } else
 282                 el = &fe->id2.i_list;
 283
 284         /* we never add a branch to a leaf. */
 285         BUG_ON(!el->l_tree_depth);
 286
 287         new_blocks = le16_to_cpu(el->l_tree_depth);
 288
 289         /* allocate the number of new eb blocks we need */
 290         new_eb_bhs = kcalloc(new_blocks, sizeof(struct buffer_head *),
 291                              GFP_KERNEL);
 292         if (!new_eb_bhs) {
 293                 status = -ENOMEM;
 294                 mlog_errno(status);
 295                 goto bail;
 296         }
 297
 298         status = ocfs2_create_new_meta_bhs(osb, handle, inode, new_blocks,
 299                                            meta_ac, new_eb_bhs);
 300         if (status < 0) {
 301                 mlog_errno(status);
 302                 goto bail;
 303         }
 304
 305         /* Note: new_eb_bhs[new_blocks - 1] is the guy which will be
 306          * linked with the rest of the tree.
 307          * conversly, new_eb_bhs[0] is the new bottommost leaf.
 308          *
 309          * when we leave the loop, new_last_eb_blk will point to the
 310          * newest leaf, and next_blkno will point to the topmost extent
 311          * block. */
 312         next_blkno = new_last_eb_blk = 0;
 313         for(i = 0; i < new_blocks; i++) {
 314                 bh = new_eb_bhs[i];
 315                 eb = (struct ocfs2_extent_block *) bh->b_data;
 316                 if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
 317                         OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
 318                         status = -EIO;
 319                         goto bail;
 320                 }
 321                 eb_el = &eb->h_list;
 322
 323                 status = ocfs2_journal_access(handle, inode, bh,
 324                                               OCFS2_JOURNAL_ACCESS_CREATE);
 325                 if (status < 0) {
 326                         mlog_errno(status);
 327                         goto bail;
 328                 }
 329
 330                 eb->h_next_leaf_blk = 0;
 331                 eb_el->l_tree_depth = cpu_to_le16(i);
 332                 eb_el->l_next_free_rec = cpu_to_le16(1);
 333                 eb_el->l_recs[0].e_cpos = fe->i_clusters;
 334                 eb_el->l_recs[0].e_blkno = cpu_to_le64(next_blkno);
 335                 eb_el->l_recs[0].e_clusters = cpu_to_le32(0);
 336                 if (!eb_el->l_tree_depth)
 337                         new_last_eb_blk = le64_to_cpu(eb->h_blkno);
 338
 339                 status = ocfs2_journal_dirty(handle, bh);
 340                 if (status < 0) {
 341                         mlog_errno(status);
 342                         goto bail;
 343                 }
 344
 345                 next_blkno = le64_to_cpu(eb->h_blkno);
 346         }
 347
 348         /* This is a bit hairy. We want to update up to three blocks
 349          * here without leaving any of them in an inconsistent state
 350          * in case of error. We don't have to worry about
 351          * journal_dirty erroring as it won't unless we've aborted the
 352          * handle (in which case we would never be here) so reserving
 353          * the write with journal_access is all we need to do. */
 354         status = ocfs2_journal_access(handle, inode, last_eb_bh,
 355                                       OCFS2_JOURNAL_ACCESS_WRITE);
 356         if (status < 0) {
 357                 mlog_errno(status);
 358                 goto bail;
 359         }
 360         status = ocfs2_journal_access(handle, inode, fe_bh,
 361                                       OCFS2_JOURNAL_ACCESS_WRITE);
 362         if (status < 0) {
 363                 mlog_errno(status);
 364                 goto bail;
 365         }
 366         if (eb_bh) {
 367                 status = ocfs2_journal_access(handle, inode, eb_bh,
 368                                               OCFS2_JOURNAL_ACCESS_WRITE);
 369                 if (status < 0) {
 370                         mlog_errno(status);
 371                         goto bail;
 372                 }
 373         }
 374
 375         /* Link the new branch into the rest of the tree (el will
 376          * either be on the fe, or the extent block passed in. */
 377         i = le16_to_cpu(el->l_next_free_rec);
 378         el->l_recs[i].e_blkno = cpu_to_le64(next_blkno);
 379         el->l_recs[i].e_cpos = fe->i_clusters;
 380         el->l_recs[i].e_clusters = 0;
 381         le16_add_cpu(&el->l_next_free_rec, 1);
 382
 383         /* fe needs a new last extent block pointer, as does the
 384          * next_leaf on the previously last-extent-block. */
 385         fe->i_last_eb_blk = cpu_to_le64(new_last_eb_blk);
 386
 387         eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
 388         eb->h_next_leaf_blk = cpu_to_le64(new_last_eb_blk);
 389
 390         status = ocfs2_journal_dirty(handle, last_eb_bh);
 391         if (status < 0)
 392                 mlog_errno(status);
 393         status = ocfs2_journal_dirty(handle, fe_bh);
 394         if (status < 0)
 395                 mlog_errno(status);
 396         if (eb_bh) {
 397                 status = ocfs2_journal_dirty(handle, eb_bh);
 398                 if (status < 0)
 399                         mlog_errno(status);
 400         }
 401
 402         status = 0;
 403 bail:
 404         if (new_eb_bhs) {
 405                 for (i = 0; i < new_blocks; i++)
 406                         if (new_eb_bhs[i])
 407                                 brelse(new_eb_bhs[i]);
 408                 kfree(new_eb_bhs);
 409         }
 410
 411         mlog_exit(status);
 412         return status;
 413 }
 414
 415 /*
 416  * adds another level to the allocation tree.
 417  * returns back the new extent block so you can add a branch to it
 418  * after this call.
 419  */
 420 static int ocfs2_shift_tree_depth(struct ocfs2_super *osb,
 421                                   handle_t *handle,
 422                                   struct inode *inode,
 423                                   struct buffer_head *fe_bh,
 424                                   struct ocfs2_alloc_context *meta_ac,
 425                                   struct buffer_head **ret_new_eb_bh)
 426 {
 427         int status, i;
 428         struct buffer_head *new_eb_bh = NULL;
 429         struct ocfs2_dinode *fe;
 430         struct ocfs2_extent_block *eb;
 431         struct ocfs2_extent_list  *fe_el;
 432         struct ocfs2_extent_list  *eb_el;
 433
 434         mlog_entry_void();
 435
 436         status = ocfs2_create_new_meta_bhs(osb, handle, inode, 1, meta_ac,
 437                                            &new_eb_bh);
 438         if (status < 0) {
 439                 mlog_errno(status);
 440                 goto bail;
 441         }
 442
 443         eb = (struct ocfs2_extent_block *) new_eb_bh->b_data;
 444         if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
 445                 OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
 446                 status = -EIO;
 447                 goto bail;
 448         }
 449
 450         eb_el = &eb->h_list;
 451         fe = (struct ocfs2_dinode *) fe_bh->b_data;
 452         fe_el = &fe->id2.i_list;
 453
 454         status = ocfs2_journal_access(handle, inode, new_eb_bh,
 455                                       OCFS2_JOURNAL_ACCESS_CREATE);
 456         if (status < 0) {
 457                 mlog_errno(status);
 458                 goto bail;
 459         }
 460
 461         /* copy the fe data into the new extent block */
 462         eb_el->l_tree_depth = fe_el->l_tree_depth;
 463         eb_el->l_next_free_rec = fe_el->l_next_free_rec;
 464         for(i = 0; i < le16_to_cpu(fe_el->l_next_free_rec); i++) {
 465                 eb_el->l_recs[i].e_cpos = fe_el->l_recs[i].e_cpos;
 466                 eb_el->l_recs[i].e_clusters = fe_el->l_recs[i].e_clusters;
 467                 eb_el->l_recs[i].e_blkno = fe_el->l_recs[i].e_blkno;
 468         }
 469
 470         status = ocfs2_journal_dirty(handle, new_eb_bh);
 471         if (status < 0) {
 472                 mlog_errno(status);
 473                 goto bail;
 474         }
 475
 476         status = ocfs2_journal_access(handle, inode, fe_bh,
 477                                       OCFS2_JOURNAL_ACCESS_WRITE);
 478         if (status < 0) {
 479                 mlog_errno(status);
 480                 goto bail;
 481         }
 482
 483         /* update fe now */
 484         le16_add_cpu(&fe_el->l_tree_depth, 1);
 485         fe_el->l_recs[0].e_cpos = 0;
 486         fe_el->l_recs[0].e_blkno = eb->h_blkno;
 487         fe_el->l_recs[0].e_clusters = fe->i_clusters;
 488         for(i = 1; i < le16_to_cpu(fe_el->l_next_free_rec); i++) {
 489                 fe_el->l_recs[i].e_cpos = 0;
 490                 fe_el->l_recs[i].e_clusters = 0;
 491                 fe_el->l_recs[i].e_blkno = 0;
 492         }
 493         fe_el->l_next_free_rec = cpu_to_le16(1);
 494
 495         /* If this is our 1st tree depth shift, then last_eb_blk
 496          * becomes the allocated extent block */
 497         if (fe_el->l_tree_depth == cpu_to_le16(1))
 498                 fe->i_last_eb_blk = eb->h_blkno;
 499
 500         status = ocfs2_journal_dirty(handle, fe_bh);
 501         if (status < 0) {
 502                 mlog_errno(status);
 503                 goto bail;
 504         }
 505
 506         *ret_new_eb_bh = new_eb_bh;
 507         new_eb_bh = NULL;
 508         status = 0;
 509 bail:
 510         if (new_eb_bh)
 511                 brelse(new_eb_bh);
 512
 513         mlog_exit(status);
 514         return status;
 515 }
 516
 517 /*
 518  * Expects the tree to already have room in the rightmost leaf for the
 519  * extent.  Updates all the extent blocks (and the dinode) on the way
 520  * down.
 521  */
 522 static int ocfs2_do_insert_extent(struct ocfs2_super *osb,
 523                                   handle_t *handle,
 524                                   struct inode *inode,
 525                                   struct buffer_head *fe_bh,
 526                                   u64 start_blk,
 527                                   u32 new_clusters)
 528 {
 529         int status, i, num_bhs = 0;
 530         u64 next_blkno;
 531         u16 next_free;
 532         struct buffer_head **eb_bhs = NULL;
 533         struct ocfs2_dinode *fe;
 534         struct ocfs2_extent_block *eb;
 535         struct ocfs2_extent_list  *el;
 536
 537         mlog_entry_void();
 538
 539         status = ocfs2_journal_access(handle, inode, fe_bh,
 540                                       OCFS2_JOURNAL_ACCESS_WRITE);
 541         if (status < 0) {
 542                 mlog_errno(status);
 543                 goto bail;
 544         }
 545
 546         fe = (struct ocfs2_dinode *) fe_bh->b_data;
 547         el = &fe->id2.i_list;
 548         if (el->l_tree_depth) {
 549                 /* This is another operation where we want to be
 550                  * careful about our tree updates. An error here means
 551                  * none of the previous changes we made should roll
 552                  * forward. As a result, we have to record the buffers
 553                  * for this part of the tree in an array and reserve a
 554                  * journal write to them before making any changes. */
 555                 num_bhs = le16_to_cpu(fe->id2.i_list.l_tree_depth);
 556                 eb_bhs = kcalloc(num_bhs, sizeof(struct buffer_head *),
 557                                  GFP_KERNEL);
 558                 if (!eb_bhs) {
 559                         status = -ENOMEM;
 560                         mlog_errno(status);
 561                         goto bail;
 562                 }
 563
 564                 i = 0;
 565                 while(el->l_tree_depth) {
 566                         next_free = le16_to_cpu(el->l_next_free_rec);
 567                         if (next_free == 0) {
 568                                 ocfs2_error(inode->i_sb,
 569                                             "Dinode %llu has a bad extent list",
 570                                             (unsigned long long)OCFS2_I(inode)->ip_blkno);
 571                                 status = -EIO;
 572                                 goto bail;
 573                         }
 574                         next_blkno = le64_to_cpu(el->l_recs[next_free - 1].e_blkno);
 575
 576                         BUG_ON(i >= num_bhs);
 577                         status = ocfs2_read_block(osb, next_blkno, &eb_bhs[i],
 578                                                   OCFS2_BH_CACHED, inode);
 579                         if (status < 0) {
 580                                 mlog_errno(status);
 581                                 goto bail;
 582                         }
 583                         eb = (struct ocfs2_extent_block *) eb_bhs[i]->b_data;
 584                         if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
 585                                 OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb,
 586                                                                  eb);
 587                                 status = -EIO;
 588                                 goto bail;
 589                         }
 590
 591                         status = ocfs2_journal_access(handle, inode, eb_bhs[i],
 592                                                       OCFS2_JOURNAL_ACCESS_WRITE);
 593                         if (status < 0) {
 594                                 mlog_errno(status);
 595                                 goto bail;
 596                         }
 597
 598                         el = &eb->h_list;
 599                         i++;
 600                         /* When we leave this loop, eb_bhs[num_bhs - 1] will
 601                          * hold the bottom-most leaf extent block. */
 602                 }
 603                 BUG_ON(el->l_tree_depth);
 604
 605                 el = &fe->id2.i_list;
 606                 /* If we have tree depth, then the fe update is
 607                  * trivial, and we want to switch el out for the
 608                  * bottom-most leaf in order to update it with the
 609                  * actual extent data below. */
 610                 next_free = le16_to_cpu(el->l_next_free_rec);
 611                 if (next_free == 0) {
 612                         ocfs2_error(inode->i_sb,
 613                                     "Dinode %llu has a bad extent list",
 614                                     (unsigned long long)OCFS2_I(inode)->ip_blkno);
 615                         status = -EIO;
 616                         goto bail;
 617                 }
 618                 le32_add_cpu(&el->l_recs[next_free - 1].e_clusters,
 619                              new_clusters);
 620                 /* (num_bhs - 1) to avoid the leaf */
 621                 for(i = 0; i < (num_bhs - 1); i++) {
 622                         eb = (struct ocfs2_extent_block *) eb_bhs[i]->b_data;
 623                         el = &eb->h_list;
 624
 625                         /* finally, make our actual change to the
 626                          * intermediate extent blocks. */
 627                         next_free = le16_to_cpu(el->l_next_free_rec);
 628                         le32_add_cpu(&el->l_recs[next_free - 1].e_clusters,
 629                                      new_clusters);
 630
 631                         status = ocfs2_journal_dirty(handle, eb_bhs[i]);
 632                         if (status < 0)
 633                                 mlog_errno(status);
 634                 }
 635                 BUG_ON(i != (num_bhs - 1));
 636                 /* note that the leaf block wasn't touched in
 637                  * the loop above */
 638                 eb = (struct ocfs2_extent_block *) eb_bhs[num_bhs - 1]->b_data;
 639                 el = &eb->h_list;
 640                 BUG_ON(el->l_tree_depth);
 641         }
 642
 643         /* yay, we can finally add the actual extent now! */
 644         i = le16_to_cpu(el->l_next_free_rec) - 1;
 645         if (le16_to_cpu(el->l_next_free_rec) &&
 646             ocfs2_extent_contig(inode, &el->l_recs[i], start_blk)) {
 647                 le32_add_cpu(&el->l_recs[i].e_clusters, new_clusters);
 648         } else if (le16_to_cpu(el->l_next_free_rec) &&
 649                    (le32_to_cpu(el->l_recs[i].e_clusters) == 0)) {
 650                 /* having an empty extent at eof is legal. */
 651                 if (el->l_recs[i].e_cpos != fe->i_clusters) {
 652                         ocfs2_error(inode->i_sb,
 653                                     "Dinode %llu trailing extent is bad: "
 654                                     "cpos (%u) != number of clusters (%u)",
 655                                     (unsigned long long)OCFS2_I(inode)->ip_blkno,
 656                                     le32_to_cpu(el->l_recs[i].e_cpos),
 657                                     le32_to_cpu(fe->i_clusters));
 658                         status = -EIO;
 659                         goto bail;
 660                 }
 661                 el->l_recs[i].e_blkno = cpu_to_le64(start_blk);
 662                 el->l_recs[i].e_clusters = cpu_to_le32(new_clusters);
 663         } else {
 664                 /* No contiguous record, or no empty record at eof, so
 665                  * we add a new one. */
 666
 667                 BUG_ON(le16_to_cpu(el->l_next_free_rec) >=
 668                        le16_to_cpu(el->l_count));
 669                 i = le16_to_cpu(el->l_next_free_rec);
 670
 671                 el->l_recs[i].e_blkno = cpu_to_le64(start_blk);
 672                 el->l_recs[i].e_clusters = cpu_to_le32(new_clusters);
 673                 el->l_recs[i].e_cpos = fe->i_clusters;
 674                 le16_add_cpu(&el->l_next_free_rec, 1);
 675         }
 676
 677         /*
 678          * extent_map errors are not fatal, so they are ignored outside
 679          * of flushing the thing.
 680          */
 681         status = ocfs2_extent_map_append(inode, &el->l_recs[i],
 682                                          new_clusters);
 683         if (status) {
 684                 mlog_errno(status);
 685                 ocfs2_extent_map_drop(inode, le32_to_cpu(fe->i_clusters));
 686         }
 687
 688         status = ocfs2_journal_dirty(handle, fe_bh);
 689         if (status < 0)
 690                 mlog_errno(status);
 691         if (fe->id2.i_list.l_tree_depth) {
 692                 status = ocfs2_journal_dirty(handle, eb_bhs[num_bhs - 1]);
 693                 if (status < 0)
 694                         mlog_errno(status);
 695         }
 696
 697         status = 0;
 698 bail:
 699         if (eb_bhs) {
 700                 for (i = 0; i < num_bhs; i++)
 701                         if (eb_bhs[i])
 702                                 brelse(eb_bhs[i]);
 703                 kfree(eb_bhs);
 704         }
 705
 706         mlog_exit(status);
 707         return status;
 708 }
 709
 710 /*
 711  * Should only be called when there is no space left in any of the
 712  * leaf nodes. What we want to do is find the lowest tree depth
 713  * non-leaf extent block with room for new records. There are three
 714  * valid results of this search:
 715  *
 716  * 1) a lowest extent block is found, then we pass it back in
 717  *    *lowest_eb_bh and return '0'
 718  *
 719  * 2) the search fails to find anything, but the dinode has room. We
 720  *    pass NULL back in *lowest_eb_bh, but still return '0'
 721  *
 722  * 3) the search fails to find anything AND the dinode is full, in
 723  *    which case we return > 0
 724  *
 725  * return status < 0 indicates an error.
 726  */
 727 static int ocfs2_find_branch_target(struct ocfs2_super *osb,
 728                                     struct inode *inode,
 729                                     struct buffer_head *fe_bh,
 730                                     struct buffer_head **target_bh)
 731 {
 732         int status = 0, i;
 733         u64 blkno;
 734         struct ocfs2_dinode *fe;
 735         struct ocfs2_extent_block *eb;
 736         struct ocfs2_extent_list  *el;
 737         struct buffer_head *bh = NULL;
 738         struct buffer_head *lowest_bh = NULL;
 739
 740         mlog_entry_void();
 741
 742         *target_bh = NULL;
 743
 744         fe = (struct ocfs2_dinode *) fe_bh->b_data;
 745         el = &fe->id2.i_list;
 746
 747         while(le16_to_cpu(el->l_tree_depth) > 1) {
 748                 if (le16_to_cpu(el->l_next_free_rec) == 0) {
 749                         ocfs2_error(inode->i_sb, "Dinode %llu has empty "
 750                                     "extent list (next_free_rec == 0)",
 751                                     (unsigned long long)OCFS2_I(inode)->ip_blkno);
 752                         status = -EIO;
 753                         goto bail;
 754                 }
 755                 i = le16_to_cpu(el->l_next_free_rec) - 1;
 756                 blkno = le64_to_cpu(el->l_recs[i].e_blkno);
 757                 if (!blkno) {
 758                         ocfs2_error(inode->i_sb, "Dinode %llu has extent "
 759                                     "list where extent # %d has no physical "
 760                                     "block start",
 761                                     (unsigned long long)OCFS2_I(inode)->ip_blkno, i);
 762                         status = -EIO;
 763                         goto bail;
 764                 }
 765
 766                 if (bh) {
 767                         brelse(bh);
 768                         bh = NULL;
 769                 }
 770
 771                 status = ocfs2_read_block(osb, blkno, &bh, OCFS2_BH_CACHED,
 772                                           inode);
 773                 if (status < 0) {
 774                         mlog_errno(status);
 775                         goto bail;
 776                 }
 777
 778                 eb = (struct ocfs2_extent_block *) bh->b_data;
 779                 if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
 780                         OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
 781                         status = -EIO;
 782                         goto bail;
 783                 }
 784                 el = &eb->h_list;
 785
 786                 if (le16_to_cpu(el->l_next_free_rec) <
 787                     le16_to_cpu(el->l_count)) {
 788                         if (lowest_bh)
 789                                 brelse(lowest_bh);
 790                         lowest_bh = bh;
 791                         get_bh(lowest_bh);
 792                 }
 793         }
 794
 795         /* If we didn't find one and the fe doesn't have any room,
 796          * then return '1' */
 797         if (!lowest_bh
 798             && (fe->id2.i_list.l_next_free_rec == fe->id2.i_list.l_count))
 799                 status = 1;
 800
 801         *target_bh = lowest_bh;
 802 bail:
 803         if (bh)
 804                 brelse(bh);
 805
 806         mlog_exit(status);
 807         return status;
 808 }
 809
 810 /* the caller needs to update fe->i_clusters */
 811 int ocfs2_insert_extent(struct ocfs2_super *osb,
 812                         handle_t *handle,
 813                         struct inode *inode,
 814                         struct buffer_head *fe_bh,
 815                         u64 start_blk,
 816                         u32 new_clusters,
 817                         struct ocfs2_alloc_context *meta_ac)
 818 {
 819         int status, i, shift;
 820         struct buffer_head *last_eb_bh = NULL;
 821         struct buffer_head *bh = NULL;
 822         struct ocfs2_dinode *fe;
 823         struct ocfs2_extent_block *eb;
 824         struct ocfs2_extent_list  *el;
 825
 826         mlog_entry_void();
 827
 828         mlog(0, "add %u clusters starting at block %llu to inode %llu\n",
 829              new_clusters, (unsigned long long)start_blk,
 830              (unsigned long long)OCFS2_I(inode)->ip_blkno);
 831
 832         fe = (struct ocfs2_dinode *) fe_bh->b_data;
 833         el = &fe->id2.i_list;
 834
 835         if (el->l_tree_depth) {
 836                 /* jump to end of tree */
 837                 status = ocfs2_read_block(osb, le64_to_cpu(fe->i_last_eb_blk),
 838                                           &last_eb_bh, OCFS2_BH_CACHED, inode);
 839                 if (status < 0) {
 840                         mlog_exit(status);
 841                         goto bail;
 842                 }
 843                 eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
 844                 el = &eb->h_list;
 845         }
 846
 847         /* Can we allocate without adding/shifting tree bits? */
 848         i = le16_to_cpu(el->l_next_free_rec) - 1;
 849         if (le16_to_cpu(el->l_next_free_rec) == 0
 850             || (le16_to_cpu(el->l_next_free_rec) < le16_to_cpu(el->l_count))
 851             || le32_to_cpu(el->l_recs[i].e_clusters) == 0
 852             || ocfs2_extent_contig(inode, &el->l_recs[i], start_blk))
 853                 goto out_add;
 854
 855         mlog(0, "ocfs2_allocate_extent: couldn't do a simple add, traversing "
 856              "tree now.\n");
 857
 858         shift = ocfs2_find_branch_target(osb, inode, fe_bh, &bh);
 859         if (shift < 0) {
 860                 status = shift;
 861                 mlog_errno(status);
 862                 goto bail;
 863         }
 864
 865         /* We traveled all the way to the bottom of the allocation tree
 866          * and didn't find room for any more extents - we need to add
 867          * another tree level */
 868         if (shift) {
 869                 /* if we hit a leaf, we'd better be empty :) */
 870                 BUG_ON(le16_to_cpu(el->l_next_free_rec) !=
 871                        le16_to_cpu(el->l_count));
 872                 BUG_ON(bh);
 873                 mlog(0, "ocfs2_allocate_extent: need to shift tree depth "
 874                      "(current = %u)\n",
 875                      le16_to_cpu(fe->id2.i_list.l_tree_depth));
 876
 877                 /* ocfs2_shift_tree_depth will return us a buffer with
 878                  * the new extent block (so we can pass that to
 879                  * ocfs2_add_branch). */
 880                 status = ocfs2_shift_tree_depth(osb, handle, inode, fe_bh,
 881                                                 meta_ac, &bh);
 882                 if (status < 0) {
 883                         mlog_errno(status);
 884                         goto bail;
 885                 }
 886                 /* Special case: we have room now if we shifted from
 887                  * tree_depth 0 */
 888                 if (fe->id2.i_list.l_tree_depth == cpu_to_le16(1))
 889                         goto out_add;
 890         }
 891
 892         /* call ocfs2_add_branch to add the final part of the tree with
 893          * the new data. */
 894         mlog(0, "ocfs2_allocate_extent: add branch. bh = %p\n", bh);
 895         status = ocfs2_add_branch(osb, handle, inode, fe_bh, bh, last_eb_bh,
 896                                   meta_ac);
 897         if (status < 0) {
 898                 mlog_errno(status);
 899                 goto bail;
 900         }
 901
 902 out_add:
 903         /* Finally, we can add clusters. */
 904         status = ocfs2_do_insert_extent(osb, handle, inode, fe_bh,
 905                                         start_blk, new_clusters);
 906         if (status < 0)
 907                 mlog_errno(status);
 908
 909 bail:
 910         if (bh)
 911                 brelse(bh);
 912
 913         if (last_eb_bh)
 914                 brelse(last_eb_bh);
 915
 916         mlog_exit(status);
 917         return status;
 918 }
 919
 920 static inline int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb)
 921 {
 922         struct buffer_head *tl_bh = osb->osb_tl_bh;
 923         struct ocfs2_dinode *di;
 924         struct ocfs2_truncate_log *tl;
 925
 926         di = (struct ocfs2_dinode *) tl_bh->b_data;
 927         tl = &di->id2.i_dealloc;
 928
 929         mlog_bug_on_msg(le16_to_cpu(tl->tl_used) > le16_to_cpu(tl->tl_count),
 930                         "slot %d, invalid truncate log parameters: used = "
 931                         "%u, count = %u\n", osb->slot_num,
 932                         le16_to_cpu(tl->tl_used), le16_to_cpu(tl->tl_count));
 933         return le16_to_cpu(tl->tl_used) == le16_to_cpu(tl->tl_count);
 934 }
 935
 936 static int ocfs2_truncate_log_can_coalesce(struct ocfs2_truncate_log *tl,
 937                                            unsigned int new_start)
 938 {
 939         unsigned int tail_index;
 940         unsigned int current_tail;
 941
 942         /* No records, nothing to coalesce */
 943         if (!le16_to_cpu(tl->tl_used))
 944                 return 0;
 945
 946         tail_index = le16_to_cpu(tl->tl_used) - 1;
 947         current_tail = le32_to_cpu(tl->tl_recs[tail_index].t_start);
 948         current_tail += le32_to_cpu(tl->tl_recs[tail_index].t_clusters);
 949
 950         return current_tail == new_start;
 951 }
 952
 953 static int ocfs2_truncate_log_append(struct ocfs2_super *osb,
 954                                      handle_t *handle,
 955                                      u64 start_blk,
 956                                      unsigned int num_clusters)
 957 {
 958         int status, index;
 959         unsigned int start_cluster, tl_count;
 960         struct inode *tl_inode = osb->osb_tl_inode;
 961         struct buffer_head *tl_bh = osb->osb_tl_bh;
 962         struct ocfs2_dinode *di;
 963         struct ocfs2_truncate_log *tl;
 964
 965         mlog_entry("start_blk = %llu, num_clusters = %u\n",
 966                    (unsigned long long)start_blk, num_clusters);
 967
 968         BUG_ON(mutex_trylock(&tl_inode->i_mutex));
 969
 970         start_cluster = ocfs2_blocks_to_clusters(osb->sb, start_blk);
 971
 972         di = (struct ocfs2_dinode *) tl_bh->b_data;
 973         tl = &di->id2.i_dealloc;
 974         if (!OCFS2_IS_VALID_DINODE(di)) {
 975                 OCFS2_RO_ON_INVALID_DINODE(osb->sb, di);
 976                 status = -EIO;
 977                 goto bail;
 978         }
 979
 980         tl_count = le16_to_cpu(tl->tl_count);
 981         mlog_bug_on_msg(tl_count > ocfs2_truncate_recs_per_inode(osb->sb) ||
 982                         tl_count == 0,
 983                         "Truncate record count on #%llu invalid "
 984                         "wanted %u, actual %u\n",
 985                         (unsigned long long)OCFS2_I(tl_inode)->ip_blkno,
 986                         ocfs2_truncate_recs_per_inode(osb->sb),
 987                         le16_to_cpu(tl->tl_count));
 988
 989         /* Caller should have known to flush before calling us. */
 990         index = le16_to_cpu(tl->tl_used);
 991         if (index >= tl_count) {
 992                 status = -ENOSPC;
 993                 mlog_errno(status);
 994                 goto bail;
 995         }
 996
 997         status = ocfs2_journal_access(handle, tl_inode, tl_bh,
 998                                       OCFS2_JOURNAL_ACCESS_WRITE);
 999         if (status < 0) {
1000                 mlog_errno(status);
1001                 goto bail;
1002         }
1003
1004         mlog(0, "Log truncate of %u clusters starting at cluster %u to "
1005              "%llu (index = %d)\n", num_clusters, start_cluster,
1006              (unsigned long long)OCFS2_I(tl_inode)->ip_blkno, index);
1007
1008         if (ocfs2_truncate_log_can_coalesce(tl, start_cluster)) {
1009                 /*
1010                  * Move index back to the record we are coalescing with.
1011                  * ocfs2_truncate_log_can_coalesce() guarantees nonzero
1012                  */
1013                 index--;
1014
1015                 num_clusters += le32_to_cpu(tl->tl_recs[index].t_clusters);
1016                 mlog(0, "Coalesce with index %u (start = %u, clusters = %u)\n",
1017                      index, le32_to_cpu(tl->tl_recs[index].t_start),
1018                      num_clusters);
1019         } else {
1020                 tl->tl_recs[index].t_start = cpu_to_le32(start_cluster);
1021                 tl->tl_used = cpu_to_le16(index + 1);
1022         }
1023         tl->tl_recs[index].t_clusters = cpu_to_le32(num_clusters);
1024
1025         status = ocfs2_journal_dirty(handle, tl_bh);
1026         if (status < 0) {
1027                 mlog_errno(status);
1028                 goto bail;
1029         }
1030
1031 bail:
1032         mlog_exit(status);
1033         return status;
1034 }
1035
1036 static int ocfs2_replay_truncate_records(struct ocfs2_super *osb,
1037                                          handle_t *handle,
1038                                          struct inode *data_alloc_inode,
1039                                          struct buffer_head *data_alloc_bh)
1040 {
1041         int status = 0;
1042         int i;
1043         unsigned int num_clusters;
1044         u64 start_blk;
1045         struct ocfs2_truncate_rec rec;
1046         struct ocfs2_dinode *di;
1047         struct ocfs2_truncate_log *tl;
1048         struct inode *tl_inode = osb->osb_tl_inode;
1049         struct buffer_head *tl_bh = osb->osb_tl_bh;
1050
1051         mlog_entry_void();
1052
1053         di = (struct ocfs2_dinode *) tl_bh->b_data;
1054         tl = &di->id2.i_dealloc;
1055         i = le16_to_cpu(tl->tl_used) - 1;
1056         while (i >= 0) {
1057                 /* Caller has given us at least enough credits to
1058                  * update the truncate log dinode */
1059                 status = ocfs2_journal_access(handle, tl_inode, tl_bh,
1060                                               OCFS2_JOURNAL_ACCESS_WRITE);
1061                 if (status < 0) {
1062                         mlog_errno(status);
1063                         goto bail;
1064                 }
1065
1066                 tl->tl_used = cpu_to_le16(i);
1067
1068                 status = ocfs2_journal_dirty(handle, tl_bh);
1069                 if (status < 0) {
1070                         mlog_errno(status);
1071                         goto bail;
1072                 }
1073
1074                 /* TODO: Perhaps we can calculate the bulk of the
1075                  * credits up front rather than extending like
1076                  * this. */
1077                 status = ocfs2_extend_trans(handle,
1078                                             OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC);
1079                 if (status < 0) {
1080                         mlog_errno(status);
1081                         goto bail;
1082                 }
1083
1084                 rec = tl->tl_recs[i];
1085                 start_blk = ocfs2_clusters_to_blocks(data_alloc_inode->i_sb,
1086                                                     le32_to_cpu(rec.t_start));
1087                 num_clusters = le32_to_cpu(rec.t_clusters);
1088
1089                 /* if start_blk is not set, we ignore the record as
1090                  * invalid. */
1091                 if (start_blk) {
1092                         mlog(0, "free record %d, start = %u, clusters = %u\n",
1093                              i, le32_to_cpu(rec.t_start), num_clusters);
1094
1095                         status = ocfs2_free_clusters(handle, data_alloc_inode,
1096                                                      data_alloc_bh, start_blk,
1097                                                      num_clusters);
1098                         if (status < 0) {
1099                                 mlog_errno(status);
1100                                 goto bail;
1101                         }
1102                 }
1103                 i--;
1104         }
1105
1106 bail:
1107         mlog_exit(status);
1108         return status;
1109 }
1110
1111 /* Expects you to already be holding tl_inode->i_mutex */
1112 static int __ocfs2_flush_truncate_log(struct ocfs2_super *osb)
1113 {
1114         int status;
1115         unsigned int num_to_flush;
1116         handle_t *handle;
1117         struct inode *tl_inode = osb->osb_tl_inode;
1118         struct inode *data_alloc_inode = NULL;
1119         struct buffer_head *tl_bh = osb->osb_tl_bh;
1120         struct buffer_head *data_alloc_bh = NULL;
1121         struct ocfs2_dinode *di;
1122         struct ocfs2_truncate_log *tl;
1123
1124         mlog_entry_void();
1125
1126         BUG_ON(mutex_trylock(&tl_inode->i_mutex));
1127
1128         di = (struct ocfs2_dinode *) tl_bh->b_data;
1129         tl = &di->id2.i_dealloc;
1130         if (!OCFS2_IS_VALID_DINODE(di)) {
1131                 OCFS2_RO_ON_INVALID_DINODE(osb->sb, di);
1132                 status = -EIO;
1133                 goto out;
1134         }
1135
1136         num_to_flush = le16_to_cpu(tl->tl_used);
1137         mlog(0, "Flush %u records from truncate log #%llu\n",
1138              num_to_flush, (unsigned long long)OCFS2_I(tl_inode)->ip_blkno);
1139         if (!num_to_flush) {
1140                 status = 0;
1141                 goto out;
1142         }
1143
1144         data_alloc_inode = ocfs2_get_system_file_inode(osb,
1145                                                        GLOBAL_BITMAP_SYSTEM_INODE,
1146                                                        OCFS2_INVALID_SLOT);
1147         if (!data_alloc_inode) {
1148                 status = -EINVAL;
1149                 mlog(ML_ERROR, "Could not get bitmap inode!\n");
1150                 goto out;
1151         }
1152
1153         mutex_lock(&data_alloc_inode->i_mutex);
1154
1155         status = ocfs2_meta_lock(data_alloc_inode, &data_alloc_bh, 1);
1156         if (status < 0) {
1157                 mlog_errno(status);
1158                 goto out_mutex;
1159         }
1160
1161         handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_UPDATE);
1162         if (IS_ERR(handle)) {
1163                 status = PTR_ERR(handle);
1164                 mlog_errno(status);
1165                 goto out_unlock;
1166         }
1167
1168         status = ocfs2_replay_truncate_records(osb, handle, data_alloc_inode,
1169                                                data_alloc_bh);
1170         if (status < 0)
1171                 mlog_errno(status);
1172
1173         ocfs2_commit_trans(osb, handle);
1174
1175 out_unlock:
1176         brelse(data_alloc_bh);
1177         ocfs2_meta_unlock(data_alloc_inode, 1);
1178
1179 out_mutex:
1180         mutex_unlock(&data_alloc_inode->i_mutex);
1181         iput(data_alloc_inode);
1182
1183 out:
1184         mlog_exit(status);
1185         return status;
1186 }
1187
1188 int ocfs2_flush_truncate_log(struct ocfs2_super *osb)
1189 {
1190         int status;
1191         struct inode *tl_inode = osb->osb_tl_inode;
1192
1193         mutex_lock(&tl_inode->i_mutex);
1194         status = __ocfs2_flush_truncate_log(osb);
1195         mutex_unlock(&tl_inode->i_mutex);
1196
1197         return status;
1198 }
1199
1200 static void ocfs2_truncate_log_worker(struct work_struct *work)
1201 {
1202         int status;
1203         struct ocfs2_super *osb =
1204                 container_of(work, struct ocfs2_super,
1205                              osb_truncate_log_wq.work);
1206
1207         mlog_entry_void();
1208
1209         status = ocfs2_flush_truncate_log(osb);
1210         if (status < 0)
1211                 mlog_errno(status);
1212
1213         mlog_exit(status);
1214 }
1215
1216 #define OCFS2_TRUNCATE_LOG_FLUSH_INTERVAL (2 * HZ)
1217 void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb,
1218                                        int cancel)
1219 {
1220         if (osb->osb_tl_inode) {
1221                 /* We want to push off log flushes while truncates are
1222                  * still running. */
1223                 if (cancel)
1224                         cancel_delayed_work(&osb->osb_truncate_log_wq);
1225
1226                 queue_delayed_work(ocfs2_wq, &osb->osb_truncate_log_wq,
1227                                    OCFS2_TRUNCATE_LOG_FLUSH_INTERVAL);
1228         }
1229 }
1230
1231 static int ocfs2_get_truncate_log_info(struct ocfs2_super *osb,
1232                                        int slot_num,
1233                                        struct inode **tl_inode,
1234                                        struct buffer_head **tl_bh)
1235 {
1236         int status;
1237         struct inode *inode = NULL;
1238         struct buffer_head *bh = NULL;
1239
1240         inode = ocfs2_get_system_file_inode(osb,
1241                                            TRUNCATE_LOG_SYSTEM_INODE,
1242                                            slot_num);
1243         if (!inode) {
1244                 status = -EINVAL;
1245                 mlog(ML_ERROR, "Could not get load truncate log inode!\n");
1246                 goto bail;
1247         }
1248
1249         status = ocfs2_read_block(osb, OCFS2_I(inode)->ip_blkno, &bh,
1250                                   OCFS2_BH_CACHED, inode);
1251         if (status < 0) {
1252                 iput(inode);
1253                 mlog_errno(status);
1254                 goto bail;
1255         }
1256
1257         *tl_inode = inode;
1258         *tl_bh    = bh;
1259 bail:
1260         mlog_exit(status);
1261         return status;
1262 }
1263
1264 /* called during the 1st stage of node recovery. we stamp a clean
1265  * truncate log and pass back a copy for processing later. if the
1266  * truncate log does not require processing, a *tl_copy is set to
1267  * NULL. */
1268 int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb,
1269                                       int slot_num,
1270                                       struct ocfs2_dinode **tl_copy)
1271 {
1272         int status;
1273         struct inode *tl_inode = NULL;
1274         struct buffer_head *tl_bh = NULL;
1275         struct ocfs2_dinode *di;
1276         struct ocfs2_truncate_log *tl;
1277
1278         *tl_copy = NULL;
1279
1280         mlog(0, "recover truncate log from slot %d\n", slot_num);
1281
1282         status = ocfs2_get_truncate_log_info(osb, slot_num, &tl_inode, &tl_bh);
1283         if (status < 0) {
1284                 mlog_errno(status);
1285                 goto bail;
1286         }
1287
1288         di = (struct ocfs2_dinode *) tl_bh->b_data;
1289         tl = &di->id2.i_dealloc;
1290         if (!OCFS2_IS_VALID_DINODE(di)) {
1291                 OCFS2_RO_ON_INVALID_DINODE(tl_inode->i_sb, di);
1292                 status = -EIO;
1293                 goto bail;
1294         }
1295
1296         if (le16_to_cpu(tl->tl_used)) {
1297                 mlog(0, "We'll have %u logs to recover\n",
1298                      le16_to_cpu(tl->tl_used));
1299
1300                 *tl_copy = kmalloc(tl_bh->b_size, GFP_KERNEL);
1301                 if (!(*tl_copy)) {
1302                         status = -ENOMEM;
1303                         mlog_errno(status);
1304                         goto bail;
1305                 }
1306
1307                 /* Assuming the write-out below goes well, this copy
1308                  * will be passed back to recovery for processing. */
1309                 memcpy(*tl_copy, tl_bh->b_data, tl_bh->b_size);
1310
1311                 /* All we need to do to clear the truncate log is set
1312                  * tl_used. */
1313                 tl->tl_used = 0;
1314
1315                 status = ocfs2_write_block(osb, tl_bh, tl_inode);
1316                 if (status < 0) {
1317                         mlog_errno(status);
1318                         goto bail;
1319                 }
1320         }
1321
1322 bail:
1323         if (tl_inode)
1324                 iput(tl_inode);
1325         if (tl_bh)
1326                 brelse(tl_bh);
1327
1328         if (status < 0 && (*tl_copy)) {
1329                 kfree(*tl_copy);
1330                 *tl_copy = NULL;
1331         }
1332
1333         mlog_exit(status);
1334         return status;
1335 }
1336
1337 int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb,
1338                                          struct ocfs2_dinode *tl_copy)
1339 {
1340         int status = 0;
1341         int i;
1342         unsigned int clusters, num_recs, start_cluster;
1343         u64 start_blk;
1344         handle_t *handle;
1345         struct inode *tl_inode = osb->osb_tl_inode;
1346         struct ocfs2_truncate_log *tl;
1347
1348         mlog_entry_void();
1349
1350         if (OCFS2_I(tl_inode)->ip_blkno == le64_to_cpu(tl_copy->i_blkno)) {
1351                 mlog(ML_ERROR, "Asked to recover my own truncate log!\n");
1352                 return -EINVAL;
1353         }
1354
1355         tl = &tl_copy->id2.i_dealloc;
1356         num_recs = le16_to_cpu(tl->tl_used);
1357         mlog(0, "cleanup %u records from %llu\n", num_recs,
1358              (unsigned long long)tl_copy->i_blkno);
1359
1360         mutex_lock(&tl_inode->i_mutex);
1361         for(i = 0; i < num_recs; i++) {
1362                 if (ocfs2_truncate_log_needs_flush(osb)) {
1363                         status = __ocfs2_flush_truncate_log(osb);
1364                         if (status < 0) {
1365                                 mlog_errno(status);
1366                                 goto bail_up;
1367                         }
1368                 }
1369
1370                 handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_UPDATE);
1371                 if (IS_ERR(handle)) {
1372                         status = PTR_ERR(handle);
1373                         mlog_errno(status);
1374                         goto bail_up;
1375                 }
1376
1377                 clusters = le32_to_cpu(tl->tl_recs[i].t_clusters);
1378                 start_cluster = le32_to_cpu(tl->tl_recs[i].t_start);
1379                 start_blk = ocfs2_clusters_to_blocks(osb->sb, start_cluster);
1380
1381                 status = ocfs2_truncate_log_append(osb, handle,
1382                                                    start_blk, clusters);
1383                 ocfs2_commit_trans(osb, handle);
1384                 if (status < 0) {
1385                         mlog_errno(status);
1386                         goto bail_up;
1387                 }
1388         }
1389
1390 bail_up:
1391         mutex_unlock(&tl_inode->i_mutex);
1392
1393         mlog_exit(status);
1394         return status;
1395 }
1396
1397 void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb)
1398 {
1399         int status;
1400         struct inode *tl_inode = osb->osb_tl_inode;
1401
1402         mlog_entry_void();
1403
1404         if (tl_inode) {
1405                 cancel_delayed_work(&osb->osb_truncate_log_wq);
1406                 flush_workqueue(ocfs2_wq);
1407
1408                 status = ocfs2_flush_truncate_log(osb);
1409                 if (status < 0)
1410                         mlog_errno(status);
1411
1412                 brelse(osb->osb_tl_bh);
1413                 iput(osb->osb_tl_inode);
1414         }
1415
1416         mlog_exit_void();
1417 }
1418
1419 int ocfs2_truncate_log_init(struct ocfs2_super *osb)
1420 {
1421         int status;
1422         struct inode *tl_inode = NULL;
1423         struct buffer_head *tl_bh = NULL;
1424
1425         mlog_entry_void();
1426
1427         status = ocfs2_get_truncate_log_info(osb,
1428                                              osb->slot_num,
1429                                              &tl_inode,
1430                                              &tl_bh);
1431         if (status < 0)
1432                 mlog_errno(status);
1433
1434         /* ocfs2_truncate_log_shutdown keys on the existence of
1435          * osb->osb_tl_inode so we don't set any of the osb variables
1436          * until we're sure all is well. */
1437         INIT_DELAYED_WORK(&osb->osb_truncate_log_wq,
1438                           ocfs2_truncate_log_worker);
1439         osb->osb_tl_bh    = tl_bh;
1440         osb->osb_tl_inode = tl_inode;
1441
1442         mlog_exit(status);
1443         return status;
1444 }
1445
1446 /* This function will figure out whether the currently last extent
1447  * block will be deleted, and if it will, what the new last extent
1448  * block will be so we can update his h_next_leaf_blk field, as well
1449  * as the dinodes i_last_eb_blk */
1450 static int ocfs2_find_new_last_ext_blk(struct ocfs2_super *osb,
1451                                        struct inode *inode,
1452                                        struct ocfs2_dinode *fe,
1453                                        u32 new_i_clusters,
1454                                        struct buffer_head *old_last_eb,
1455                                        struct buffer_head **new_last_eb)
1456 {
1457         int i, status = 0;
1458         u64 block = 0;
1459         struct ocfs2_extent_block *eb;
1460         struct ocfs2_extent_list *el;
1461         struct buffer_head *bh = NULL;
1462
1463         *new_last_eb = NULL;
1464
1465         if (!OCFS2_IS_VALID_DINODE(fe)) {
1466                 OCFS2_RO_ON_INVALID_DINODE(inode->i_sb, fe);
1467                 status = -EIO;
1468                 goto bail;
1469         }
1470
1471         /* we have no tree, so of course, no last_eb. */
1472         if (!fe->id2.i_list.l_tree_depth)
1473                 goto bail;
1474
1475         /* trunc to zero special case - this makes tree_depth = 0
1476          * regardless of what it is.  */
1477         if (!new_i_clusters)
1478                 goto bail;
1479
1480         eb = (struct ocfs2_extent_block *) old_last_eb->b_data;
1481         el = &(eb->h_list);
1482         BUG_ON(!el->l_next_free_rec);
1483
1484         /* Make sure that this guy will actually be empty after we
1485          * clear away the data. */
1486         if (le32_to_cpu(el->l_recs[0].e_cpos) < new_i_clusters)
1487                 goto bail;
1488
1489         /* Ok, at this point, we know that last_eb will definitely
1490          * change, so lets traverse the tree and find the second to
1491          * last extent block. */
1492         el = &(fe->id2.i_list);
1493         /* go down the tree, */
1494         do {
1495                 for(i = (le16_to_cpu(el->l_next_free_rec) - 1); i >= 0; i--) {
1496                         if (le32_to_cpu(el->l_recs[i].e_cpos) <
1497                             new_i_clusters) {
1498                                 block = le64_to_cpu(el->l_recs[i].e_blkno);
1499                                 break;
1500                         }
1501                 }
1502                 BUG_ON(i < 0);
1503
1504                 if (bh) {
1505                         brelse(bh);
1506                         bh = NULL;
1507                 }
1508
1509                 status = ocfs2_read_block(osb, block, &bh, OCFS2_BH_CACHED,
1510                                          inode);
1511                 if (status < 0) {
1512                         mlog_errno(status);
1513                         goto bail;
1514                 }
1515                 eb = (struct ocfs2_extent_block *) bh->b_data;
1516                 el = &eb->h_list;
1517                 if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
1518                         OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
1519                         status = -EIO;
1520                         goto bail;
1521                 }
1522         } while (el->l_tree_depth);
1523
1524         *new_last_eb = bh;
1525         get_bh(*new_last_eb);
1526         mlog(0, "returning block %llu\n",
1527              (unsigned long long)le64_to_cpu(eb->h_blkno));
1528 bail:
1529         if (bh)
1530                 brelse(bh);
1531
1532         return status;
1533 }
1534
1535 static int ocfs2_do_truncate(struct ocfs2_super *osb,
1536                              unsigned int clusters_to_del,
1537                              struct inode *inode,
1538                              struct buffer_head *fe_bh,
1539                              struct buffer_head *old_last_eb_bh,
1540                              handle_t *handle,
1541                              struct ocfs2_truncate_context *tc)
1542 {
1543         int status, i, depth;
1544         struct ocfs2_dinode *fe;
1545         struct ocfs2_extent_block *eb;
1546         struct ocfs2_extent_block *last_eb = NULL;
1547         struct ocfs2_extent_list *el;
1548         struct buffer_head *eb_bh = NULL;
1549         struct buffer_head *last_eb_bh = NULL;
1550         u64 next_eb = 0;
1551         u64 delete_blk = 0;
1552
1553         fe = (struct ocfs2_dinode *) fe_bh->b_data;
1554
1555         status = ocfs2_find_new_last_ext_blk(osb,
1556                                              inode,
1557                                              fe,
1558                                              le32_to_cpu(fe->i_clusters) -
1559                                                         clusters_to_del,
1560                                              old_last_eb_bh,
1561                                              &last_eb_bh);
1562         if (status < 0) {
1563                 mlog_errno(status);
1564                 goto bail;
1565         }
1566         if (last_eb_bh)
1567                 last_eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
1568
1569         status = ocfs2_journal_access(handle, inode, fe_bh,
1570                                       OCFS2_JOURNAL_ACCESS_WRITE);
1571         if (status < 0) {
1572                 mlog_errno(status);
1573                 goto bail;
1574         }
1575         el = &(fe->id2.i_list);
1576
1577         spin_lock(&OCFS2_I(inode)->ip_lock);
1578         OCFS2_I(inode)->ip_clusters = le32_to_cpu(fe->i_clusters) -
1579                                       clusters_to_del;
1580         spin_unlock(&OCFS2_I(inode)->ip_lock);
1581         le32_add_cpu(&fe->i_clusters, -clusters_to_del);
1582         fe->i_mtime = cpu_to_le64(CURRENT_TIME.tv_sec);
1583         fe->i_mtime_nsec = cpu_to_le32(CURRENT_TIME.tv_nsec);
1584
1585         i = le16_to_cpu(el->l_next_free_rec) - 1;
1586
1587         BUG_ON(le32_to_cpu(el->l_recs[i].e_clusters) < clusters_to_del);
1588         le32_add_cpu(&el->l_recs[i].e_clusters, -clusters_to_del);
1589         /* tree depth zero, we can just delete the clusters, otherwise
1590          * we need to record the offset of the next level extent block
1591          * as we may overwrite it. */
1592         if (!el->l_tree_depth)
1593                 delete_blk = le64_to_cpu(el->l_recs[i].e_blkno)
1594                         + ocfs2_clusters_to_blocks(osb->sb,
1595                                         le32_to_cpu(el->l_recs[i].e_clusters));
1596         else
1597                 next_eb = le64_to_cpu(el->l_recs[i].e_blkno);
1598
1599         if (!el->l_recs[i].e_clusters) {
1600                 /* if we deleted the whole extent record, then clear
1601                  * out the other fields and update the extent
1602                  * list. For depth > 0 trees, we've already recorded
1603                  * the extent block in 'next_eb' */
1604                 el->l_recs[i].e_cpos = 0;
1605                 el->l_recs[i].e_blkno = 0;
1606                 BUG_ON(!el->l_next_free_rec);
1607                 le16_add_cpu(&el->l_next_free_rec, -1);
1608         }
1609
1610         depth = le16_to_cpu(el->l_tree_depth);
1611         if (!fe->i_clusters) {
1612                 /* trunc to zero is a special case. */
1613                 el->l_tree_depth = 0;
1614                 fe->i_last_eb_blk = 0;
1615         } else if (last_eb)
1616                 fe->i_last_eb_blk = last_eb->h_blkno;
1617
1618         status = ocfs2_journal_dirty(handle, fe_bh);
1619         if (status < 0) {
1620                 mlog_errno(status);
1621                 goto bail;
1622         }
1623
1624         if (last_eb) {
1625                 /* If there will be a new last extent block, then by
1626                  * definition, there cannot be any leaves to the right of
1627                  * him. */
1628                 status = ocfs2_journal_access(handle, inode, last_eb_bh,
1629                                               OCFS2_JOURNAL_ACCESS_WRITE);
1630                 if (status < 0) {
1631                         mlog_errno(status);
1632                         goto bail;
1633                 }
1634                 last_eb->h_next_leaf_blk = 0;
1635                 status = ocfs2_journal_dirty(handle, last_eb_bh);
1636                 if (status < 0) {
1637                         mlog_errno(status);
1638                         goto bail;
1639                 }
1640         }
1641
1642         /* if our tree depth > 0, update all the tree blocks below us. */
1643         while (depth) {
1644                 mlog(0, "traveling tree (depth = %d, next_eb = %llu)\n",
1645                      depth,  (unsigned long long)next_eb);
1646                 status = ocfs2_read_block(osb, next_eb, &eb_bh,
1647                                           OCFS2_BH_CACHED, inode);
1648                 if (status < 0) {
1649                         mlog_errno(status);
1650                         goto bail;
1651                 }
1652                 eb = (struct ocfs2_extent_block *)eb_bh->b_data;
1653                 if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
1654                         OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
1655                         status = -EIO;
1656                         goto bail;
1657                 }
1658                 el = &(eb->h_list);
1659
1660                 status = ocfs2_journal_access(handle, inode, eb_bh,
1661                                               OCFS2_JOURNAL_ACCESS_WRITE);
1662                 if (status < 0) {
1663                         mlog_errno(status);
1664                         goto bail;
1665                 }
1666
1667                 BUG_ON(le16_to_cpu(el->l_next_free_rec) == 0);
1668                 BUG_ON(depth != (le16_to_cpu(el->l_tree_depth) + 1));
1669
1670                 i = le16_to_cpu(el->l_next_free_rec) - 1;
1671
1672                 mlog(0, "extent block %llu, before: record %d: "
1673                      "(%u, %u, %llu), next = %u\n",
1674                      (unsigned long long)le64_to_cpu(eb->h_blkno), i,
1675                      le32_to_cpu(el->l_recs[i].e_cpos),
1676                      le32_to_cpu(el->l_recs[i].e_clusters),
1677                      (unsigned long long)le64_to_cpu(el->l_recs[i].e_blkno),
1678                      le16_to_cpu(el->l_next_free_rec));
1679
1680                 BUG_ON(le32_to_cpu(el->l_recs[i].e_clusters) < clusters_to_del);
1681                 le32_add_cpu(&el->l_recs[i].e_clusters, -clusters_to_del);
1682
1683                 next_eb = le64_to_cpu(el->l_recs[i].e_blkno);
1684                 /* bottom-most block requires us to delete data.*/
1685                 if (!el->l_tree_depth)
1686                         delete_blk = le64_to_cpu(el->l_recs[i].e_blkno)
1687                                 + ocfs2_clusters_to_blocks(osb->sb,
1688                                         le32_to_cpu(el->l_recs[i].e_clusters));
1689                 if (!el->l_recs[i].e_clusters) {
1690                         el->l_recs[i].e_cpos = 0;
1691                         el->l_recs[i].e_blkno = 0;
1692                         BUG_ON(!el->l_next_free_rec);
1693                         le16_add_cpu(&el->l_next_free_rec, -1);
1694                 }
1695                 mlog(0, "extent block %llu, after: record %d: "
1696                      "(%u, %u, %llu), next = %u\n",
1697                      (unsigned long long)le64_to_cpu(eb->h_blkno), i,
1698                      le32_to_cpu(el->l_recs[i].e_cpos),
1699                      le32_to_cpu(el->l_recs[i].e_clusters),
1700                      (unsigned long long)le64_to_cpu(el->l_recs[i].e_blkno),
1701                      le16_to_cpu(el->l_next_free_rec));
1702
1703                 status = ocfs2_journal_dirty(handle, eb_bh);
1704                 if (status < 0) {
1705                         mlog_errno(status);
1706                         goto bail;
1707                 }
1708
1709                 if (!el->l_next_free_rec) {
1710                         mlog(0, "deleting this extent block.\n");
1711
1712                         ocfs2_remove_from_cache(inode, eb_bh);
1713
1714                         BUG_ON(el->l_recs[0].e_clusters);
1715                         BUG_ON(el->l_recs[0].e_cpos);
1716                         BUG_ON(el->l_recs[0].e_blkno);
1717                         if (eb->h_suballoc_slot == 0) {
1718                                 /*
1719                                  * This code only understands how to
1720                                  * lock the suballocator in slot 0,
1721                                  * which is fine because allocation is
1722                                  * only ever done out of that
1723                                  * suballocator too. A future version
1724                                  * might change that however, so avoid
1725                                  * a free if we don't know how to
1726                                  * handle it. This way an fs incompat
1727                                  * bit will not be necessary.
1728                                  */
1729                                 status = ocfs2_free_extent_block(handle,
1730                                                                  tc->tc_ext_alloc_inode,
1731                                                                  tc->tc_ext_alloc_bh,
1732                                                                  eb);
1733                                 if (status < 0) {
1734                                         mlog_errno(status);
1735                                         goto bail;
1736                                 }
1737                         }
1738                 }
1739                 brelse(eb_bh);
1740                 eb_bh = NULL;
1741                 depth--;
1742         }
1743
1744         BUG_ON(!delete_blk);
1745         status = ocfs2_truncate_log_append(osb, handle, delete_blk,
1746                                            clusters_to_del);
1747         if (status < 0) {
1748                 mlog_errno(status);
1749                 goto bail;
1750         }
1751         status = 0;
1752 bail:
1753         if (!status)
1754                 ocfs2_extent_map_trunc(inode, le32_to_cpu(fe->i_clusters));
1755         else
1756                 ocfs2_extent_map_drop(inode, 0);
1757         mlog_exit(status);
1758         return status;
1759 }
1760
1761 /*
1762  * It is expected, that by the time you call this function,
1763  * inode->i_size and fe->i_size have been adjusted.
1764  *
1765  * WARNING: This will kfree the truncate context
1766  */
1767 int ocfs2_commit_truncate(struct ocfs2_super *osb,
1768                           struct inode *inode,
1769                           struct buffer_head *fe_bh,
1770                           struct ocfs2_truncate_context *tc)
1771 {
1772         int status, i, credits, tl_sem = 0;
1773         u32 clusters_to_del, target_i_clusters;
1774         u64 last_eb = 0;
1775         struct ocfs2_dinode *fe;
1776         struct ocfs2_extent_block *eb;
1777         struct ocfs2_extent_list *el;
1778         struct buffer_head *last_eb_bh;
1779         handle_t *handle = NULL;
1780         struct inode *tl_inode = osb->osb_tl_inode;
1781
1782         mlog_entry_void();
1783
1784         down_write(&OCFS2_I(inode)->ip_alloc_sem);
1785
1786         target_i_clusters = ocfs2_clusters_for_bytes(osb->sb,
1787                                                      i_size_read(inode));
1788
1789         last_eb_bh = tc->tc_last_eb_bh;
1790         tc->tc_last_eb_bh = NULL;
1791
1792         fe = (struct ocfs2_dinode *) fe_bh->b_data;
1793
1794         if (fe->id2.i_list.l_tree_depth) {
1795                 eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
1796                 el = &eb->h_list;
1797         } else
1798                 el = &fe->id2.i_list;
1799         last_eb = le64_to_cpu(fe->i_last_eb_blk);
1800 start:
1801         mlog(0, "ocfs2_commit_truncate: fe->i_clusters = %u, "
1802              "last_eb = %llu, fe->i_last_eb_blk = %llu, "
1803              "fe->id2.i_list.l_tree_depth = %u last_eb_bh = %p\n",
1804              le32_to_cpu(fe->i_clusters), (unsigned long long)last_eb,
1805              (unsigned long long)le64_to_cpu(fe->i_last_eb_blk),
1806              le16_to_cpu(fe->id2.i_list.l_tree_depth), last_eb_bh);
1807
1808         if (last_eb != le64_to_cpu(fe->i_last_eb_blk)) {
1809                 mlog(0, "last_eb changed!\n");
1810                 BUG_ON(!fe->id2.i_list.l_tree_depth);
1811                 last_eb = le64_to_cpu(fe->i_last_eb_blk);
1812                 /* i_last_eb_blk may have changed, read it if
1813                  * necessary. We don't have to worry about the
1814                  * truncate to zero case here (where there becomes no
1815                  * last_eb) because we never loop back after our work
1816                  * is done. */
1817                 if (last_eb_bh) {
1818                         brelse(last_eb_bh);
1819                         last_eb_bh = NULL;
1820                 }
1821
1822                 status = ocfs2_read_block(osb, last_eb,
1823                                           &last_eb_bh, OCFS2_BH_CACHED,
1824                                           inode);
1825                 if (status < 0) {
1826                         mlog_errno(status);
1827                         goto bail;
1828                 }
1829                 eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
1830                 if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
1831                         OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
1832                         status = -EIO;
1833                         goto bail;
1834                 }
1835                 el = &(eb->h_list);
1836         }
1837
1838         /* by now, el will point to the extent list on the bottom most
1839          * portion of this tree. */
1840         i = le16_to_cpu(el->l_next_free_rec) - 1;
1841         if (le32_to_cpu(el->l_recs[i].e_cpos) >= target_i_clusters)
1842                 clusters_to_del = le32_to_cpu(el->l_recs[i].e_clusters);
1843         else
1844                 clusters_to_del = (le32_to_cpu(el->l_recs[i].e_clusters) +
1845                                    le32_to_cpu(el->l_recs[i].e_cpos)) -
1846                                   target_i_clusters;
1847
1848         mlog(0, "clusters_to_del = %u in this pass\n", clusters_to_del);
1849
1850         mutex_lock(&tl_inode->i_mutex);
1851         tl_sem = 1;
1852         /* ocfs2_truncate_log_needs_flush guarantees us at least one
1853          * record is free for use. If there isn't any, we flush to get
1854          * an empty truncate log.  */
1855         if (ocfs2_truncate_log_needs_flush(osb)) {
1856                 status = __ocfs2_flush_truncate_log(osb);
1857                 if (status < 0) {
1858                         mlog_errno(status);
1859                         goto bail;
1860                 }
1861         }
1862
1863         credits = ocfs2_calc_tree_trunc_credits(osb->sb, clusters_to_del,
1864                                                 fe, el);
1865         handle = ocfs2_start_trans(osb, credits);
1866         if (IS_ERR(handle)) {
1867                 status = PTR_ERR(handle);
1868                 handle = NULL;
1869                 mlog_errno(status);
1870                 goto bail;
1871         }
1872
1873         inode->i_ctime = inode->i_mtime = CURRENT_TIME;
1874         status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
1875         if (status < 0)
1876                 mlog_errno(status);
1877
1878         status = ocfs2_do_truncate(osb, clusters_to_del, inode, fe_bh,
1879                                    last_eb_bh, handle, tc);
1880         if (status < 0) {
1881                 mlog_errno(status);
1882                 goto bail;
1883         }
1884
1885         mutex_unlock(&tl_inode->i_mutex);
1886         tl_sem = 0;
1887
1888         ocfs2_commit_trans(osb, handle);
1889         handle = NULL;
1890
1891         BUG_ON(le32_to_cpu(fe->i_clusters) < target_i_clusters);
1892         if (le32_to_cpu(fe->i_clusters) > target_i_clusters)
1893                 goto start;
1894 bail:
1895         up_write(&OCFS2_I(inode)->ip_alloc_sem);
1896
1897         ocfs2_schedule_truncate_log_flush(osb, 1);
1898
1899         if (tl_sem)
1900                 mutex_unlock(&tl_inode->i_mutex);
1901
1902         if (handle)
1903                 ocfs2_commit_trans(osb, handle);
1904
1905         if (last_eb_bh)
1906                 brelse(last_eb_bh);
1907
1908         /* This will drop the ext_alloc cluster lock for us */
1909         ocfs2_free_truncate_context(tc);
1910
1911         mlog_exit(status);
1912         return status;
1913 }
1914
1915
1916 /*
1917  * Expects the inode to already be locked. This will figure out which
1918  * inodes need to be locked and will put them on the returned truncate
1919  * context.
1920  */
1921 int ocfs2_prepare_truncate(struct ocfs2_super *osb,
1922                            struct inode *inode,
1923                            struct buffer_head *fe_bh,
1924                            struct ocfs2_truncate_context **tc)
1925 {
1926         int status, metadata_delete;
1927         unsigned int new_i_clusters;
1928         struct ocfs2_dinode *fe;
1929         struct ocfs2_extent_block *eb;
1930         struct ocfs2_extent_list *el;
1931         struct buffer_head *last_eb_bh = NULL;
1932         struct inode *ext_alloc_inode = NULL;
1933         struct buffer_head *ext_alloc_bh = NULL;
1934
1935         mlog_entry_void();
1936
1937         *tc = NULL;
1938
1939         new_i_clusters = ocfs2_clusters_for_bytes(osb->sb,
1940                                                   i_size_read(inode));
1941         fe = (struct ocfs2_dinode *) fe_bh->b_data;
1942
1943         mlog(0, "fe->i_clusters = %u, new_i_clusters = %u, fe->i_size ="
1944              "%llu\n", fe->i_clusters, new_i_clusters,
1945              (unsigned long long)fe->i_size);
1946
1947         if (le32_to_cpu(fe->i_clusters) <= new_i_clusters) {
1948                 ocfs2_error(inode->i_sb, "Dinode %llu has cluster count "
1949                             "%u and size %llu whereas struct inode has "
1950                             "cluster count %u and size %llu which caused an "
1951                             "invalid truncate to %u clusters.",
1952                             (unsigned long long)le64_to_cpu(fe->i_blkno),
1953                             le32_to_cpu(fe->i_clusters),
1954                             (unsigned long long)le64_to_cpu(fe->i_size),
1955                             OCFS2_I(inode)->ip_clusters, i_size_read(inode),
1956                             new_i_clusters);
1957                 mlog_meta_lvb(ML_ERROR, &OCFS2_I(inode)->ip_meta_lockres);
1958                 status = -EIO;
1959                 goto bail;
1960         }
1961
1962         *tc = kzalloc(sizeof(struct ocfs2_truncate_context), GFP_KERNEL);
1963         if (!(*tc)) {
1964                 status = -ENOMEM;
1965                 mlog_errno(status);
1966                 goto bail;
1967         }
1968
1969         metadata_delete = 0;
1970         if (fe->id2.i_list.l_tree_depth) {
1971                 /* If we have a tree, then the truncate may result in
1972                  * metadata deletes. Figure this out from the
1973                  * rightmost leaf block.*/
1974                 status = ocfs2_read_block(osb, le64_to_cpu(fe->i_last_eb_blk),
1975                                           &last_eb_bh, OCFS2_BH_CACHED, inode);
1976                 if (status < 0) {
1977                         mlog_errno(status);
1978                         goto bail;
1979                 }
1980                 eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
1981                 if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
1982                         OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
1983
1984                         brelse(last_eb_bh);
1985                         status = -EIO;
1986                         goto bail;
1987                 }
1988                 el = &(eb->h_list);
1989                 if (le32_to_cpu(el->l_recs[0].e_cpos) >= new_i_clusters)
1990                         metadata_delete = 1;
1991         }
1992
1993         (*tc)->tc_last_eb_bh = last_eb_bh;
1994
1995         if (metadata_delete) {
1996                 mlog(0, "Will have to delete metadata for this trunc. "
1997                      "locking allocator.\n");
1998                 ext_alloc_inode = ocfs2_get_system_file_inode(osb, EXTENT_ALLOC_SYSTEM_INODE, 0);
1999                 if (!ext_alloc_inode) {
2000                         status = -ENOMEM;
2001                         mlog_errno(status);
2002                         goto bail;
2003                 }
2004
2005                 mutex_lock(&ext_alloc_inode->i_mutex);
2006                 (*tc)->tc_ext_alloc_inode = ext_alloc_inode;
2007
2008                 status = ocfs2_meta_lock(ext_alloc_inode, &ext_alloc_bh, 1);
2009                 if (status < 0) {
2010                         mlog_errno(status);
2011                         goto bail;
2012                 }
2013                 (*tc)->tc_ext_alloc_bh = ext_alloc_bh;
2014                 (*tc)->tc_ext_alloc_locked = 1;
2015         }
2016
2017         status = 0;
2018 bail:
2019         if (status < 0) {
2020                 if (*tc)
2021                         ocfs2_free_truncate_context(*tc);
2022                 *tc = NULL;
2023         }
2024         mlog_exit_void();
2025         return status;
2026 }
2027
2028 static void ocfs2_free_truncate_context(struct ocfs2_truncate_context *tc)
2029 {
2030         if (tc->tc_ext_alloc_inode) {
2031                 if (tc->tc_ext_alloc_locked)
2032                         ocfs2_meta_unlock(tc->tc_ext_alloc_inode, 1);
2033
2034                 mutex_unlock(&tc->tc_ext_alloc_inode->i_mutex);
2035                 iput(tc->tc_ext_alloc_inode);
2036         }
2037
2038         if (tc->tc_ext_alloc_bh)
2039                 brelse(tc->tc_ext_alloc_bh);
2040
2041         if (tc->tc_last_eb_bh)
2042                 brelse(tc->tc_last_eb_bh);
2043
2044         kfree(tc);
2045 }