SAFE public projects git trees. - safe/jmp/linux-2.6/blob - fs/ocfs2/suballoc.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * suballoc.c
   5  *
   6  * metadata alloc and free
   7  * Inspired by ext3 block groups.
   8  *
   9  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public
  13  * License as published by the Free Software Foundation; either
  14  * version 2 of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public
  22  * License along with this program; if not, write to the
  23  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24  * Boston, MA 021110-1307, USA.
  25  */
  26
  27 #include <linux/fs.h>
  28 #include <linux/types.h>
  29 #include <linux/slab.h>
  30 #include <linux/highmem.h>
  31
  32 #define MLOG_MASK_PREFIX ML_DISK_ALLOC
  33 #include <cluster/masklog.h>
  34
  35 #include "ocfs2.h"
  36
  37 #include "alloc.h"
  38 #include "blockcheck.h"
  39 #include "dlmglue.h"
  40 #include "inode.h"
  41 #include "journal.h"
  42 #include "localalloc.h"
  43 #include "suballoc.h"
  44 #include "super.h"
  45 #include "sysfile.h"
  46 #include "uptodate.h"
  47
  48 #include "buffer_head_io.h"
  49
  50 #define NOT_ALLOC_NEW_GROUP             0
  51 #define ALLOC_NEW_GROUP                 0x1
  52 #define ALLOC_GROUPS_FROM_GLOBAL        0x2
  53
  54 #define OCFS2_MAX_INODES_TO_STEAL       1024
  55
  56 static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg);
  57 static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe);
  58 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl);
  59 static int ocfs2_block_group_fill(handle_t *handle,
  60                                   struct inode *alloc_inode,
  61                                   struct buffer_head *bg_bh,
  62                                   u64 group_blkno,
  63                                   u16 my_chain,
  64                                   struct ocfs2_chain_list *cl);
  65 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
  66                                    struct inode *alloc_inode,
  67                                    struct buffer_head *bh,
  68                                    u64 max_block,
  69                                    u64 *last_alloc_group,
  70                                    int flags);
  71
  72 static int ocfs2_cluster_group_search(struct inode *inode,
  73                                       struct buffer_head *group_bh,
  74                                       u32 bits_wanted, u32 min_bits,
  75                                       u64 max_block,
  76                                       u16 *bit_off, u16 *bits_found);
  77 static int ocfs2_block_group_search(struct inode *inode,
  78                                     struct buffer_head *group_bh,
  79                                     u32 bits_wanted, u32 min_bits,
  80                                     u64 max_block,
  81                                     u16 *bit_off, u16 *bits_found);
  82 static int ocfs2_claim_suballoc_bits(struct ocfs2_super *osb,
  83                                      struct ocfs2_alloc_context *ac,
  84                                      handle_t *handle,
  85                                      u32 bits_wanted,
  86                                      u32 min_bits,
  87                                      u16 *bit_off,
  88                                      unsigned int *num_bits,
  89                                      u64 *bg_blkno);
  90 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
  91                                          int nr);
  92 static inline int ocfs2_block_group_set_bits(handle_t *handle,
  93                                              struct inode *alloc_inode,
  94                                              struct ocfs2_group_desc *bg,
  95                                              struct buffer_head *group_bh,
  96                                              unsigned int bit_off,
  97                                              unsigned int num_bits);
  98 static inline int ocfs2_block_group_clear_bits(handle_t *handle,
  99                                                struct inode *alloc_inode,
 100                                                struct ocfs2_group_desc *bg,
 101                                                struct buffer_head *group_bh,
 102                                                unsigned int bit_off,
 103                                                unsigned int num_bits);
 104
 105 static int ocfs2_relink_block_group(handle_t *handle,
 106                                     struct inode *alloc_inode,
 107                                     struct buffer_head *fe_bh,
 108                                     struct buffer_head *bg_bh,
 109                                     struct buffer_head *prev_bg_bh,
 110                                     u16 chain);
 111 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
 112                                                      u32 wanted);
 113 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
 114                                                    u64 bg_blkno,
 115                                                    u16 bg_bit_off);
 116 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
 117                                                 u64 data_blkno,
 118                                                 u64 *bg_blkno,
 119                                                 u16 *bg_bit_off);
 120 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
 121                                              u32 bits_wanted, u64 max_block,
 122                                              int flags,
 123                                              struct ocfs2_alloc_context **ac);
 124
 125 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
 126 {
 127         struct inode *inode = ac->ac_inode;
 128
 129         if (inode) {
 130                 if (ac->ac_which != OCFS2_AC_USE_LOCAL)
 131                         ocfs2_inode_unlock(inode, 1);
 132
 133                 mutex_unlock(&inode->i_mutex);
 134
 135                 iput(inode);
 136                 ac->ac_inode = NULL;
 137         }
 138         brelse(ac->ac_bh);
 139         ac->ac_bh = NULL;
 140 }
 141
 142 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
 143 {
 144         ocfs2_free_ac_resource(ac);
 145         kfree(ac);
 146 }
 147
 148 static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
 149 {
 150         return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc);
 151 }
 152
 153 #define do_error(fmt, ...)                                              \
 154         do{                                                             \
 155                 if (clean_error)                                        \
 156                         mlog(ML_ERROR, fmt "\n", ##__VA_ARGS__);        \
 157                 else                                                    \
 158                         ocfs2_error(sb, fmt, ##__VA_ARGS__);            \
 159         } while (0)
 160
 161 static int ocfs2_validate_gd_self(struct super_block *sb,
 162                                   struct buffer_head *bh,
 163                                   int clean_error)
 164 {
 165         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 166
 167         if (!OCFS2_IS_VALID_GROUP_DESC(gd)) {
 168                 do_error("Group descriptor #%llu has bad signature %.*s",
 169                          (unsigned long long)bh->b_blocknr, 7,
 170                          gd->bg_signature);
 171                 return -EINVAL;
 172         }
 173
 174         if (le64_to_cpu(gd->bg_blkno) != bh->b_blocknr) {
 175                 do_error("Group descriptor #%llu has an invalid bg_blkno "
 176                          "of %llu",
 177                          (unsigned long long)bh->b_blocknr,
 178                          (unsigned long long)le64_to_cpu(gd->bg_blkno));
 179                 return -EINVAL;
 180         }
 181
 182         if (le32_to_cpu(gd->bg_generation) != OCFS2_SB(sb)->fs_generation) {
 183                 do_error("Group descriptor #%llu has an invalid "
 184                          "fs_generation of #%u",
 185                          (unsigned long long)bh->b_blocknr,
 186                          le32_to_cpu(gd->bg_generation));
 187                 return -EINVAL;
 188         }
 189
 190         if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) {
 191                 do_error("Group descriptor #%llu has bit count %u but "
 192                          "claims that %u are free",
 193                          (unsigned long long)bh->b_blocknr,
 194                          le16_to_cpu(gd->bg_bits),
 195                          le16_to_cpu(gd->bg_free_bits_count));
 196                 return -EINVAL;
 197         }
 198
 199         if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) {
 200                 do_error("Group descriptor #%llu has bit count %u but "
 201                          "max bitmap bits of %u",
 202                          (unsigned long long)bh->b_blocknr,
 203                          le16_to_cpu(gd->bg_bits),
 204                          8 * le16_to_cpu(gd->bg_size));
 205                 return -EINVAL;
 206         }
 207
 208         return 0;
 209 }
 210
 211 static int ocfs2_validate_gd_parent(struct super_block *sb,
 212                                     struct ocfs2_dinode *di,
 213                                     struct buffer_head *bh,
 214                                     int clean_error)
 215 {
 216         unsigned int max_bits;
 217         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 218
 219         if (di->i_blkno != gd->bg_parent_dinode) {
 220                 do_error("Group descriptor #%llu has bad parent "
 221                          "pointer (%llu, expected %llu)",
 222                          (unsigned long long)bh->b_blocknr,
 223                          (unsigned long long)le64_to_cpu(gd->bg_parent_dinode),
 224                          (unsigned long long)le64_to_cpu(di->i_blkno));
 225                 return -EINVAL;
 226         }
 227
 228         max_bits = le16_to_cpu(di->id2.i_chain.cl_cpg) * le16_to_cpu(di->id2.i_chain.cl_bpc);
 229         if (le16_to_cpu(gd->bg_bits) > max_bits) {
 230                 do_error("Group descriptor #%llu has bit count of %u",
 231                          (unsigned long long)bh->b_blocknr,
 232                          le16_to_cpu(gd->bg_bits));
 233                 return -EINVAL;
 234         }
 235
 236         if (le16_to_cpu(gd->bg_chain) >=
 237             le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) {
 238                 do_error("Group descriptor #%llu has bad chain %u",
 239                          (unsigned long long)bh->b_blocknr,
 240                          le16_to_cpu(gd->bg_chain));
 241                 return -EINVAL;
 242         }
 243
 244         return 0;
 245 }
 246
 247 #undef do_error
 248
 249 /*
 250  * This version only prints errors.  It does not fail the filesystem, and
 251  * exists only for resize.
 252  */
 253 int ocfs2_check_group_descriptor(struct super_block *sb,
 254                                  struct ocfs2_dinode *di,
 255                                  struct buffer_head *bh)
 256 {
 257         int rc;
 258         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 259
 260         BUG_ON(!buffer_uptodate(bh));
 261
 262         /*
 263          * If the ecc fails, we return the error but otherwise
 264          * leave the filesystem running.  We know any error is
 265          * local to this block.
 266          */
 267         rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 268         if (rc) {
 269                 mlog(ML_ERROR,
 270                      "Checksum failed for group descriptor %llu\n",
 271                      (unsigned long long)bh->b_blocknr);
 272         } else
 273                 rc = ocfs2_validate_gd_self(sb, bh, 1);
 274         if (!rc)
 275                 rc = ocfs2_validate_gd_parent(sb, di, bh, 1);
 276
 277         return rc;
 278 }
 279
 280 static int ocfs2_validate_group_descriptor(struct super_block *sb,
 281                                            struct buffer_head *bh)
 282 {
 283         int rc;
 284         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 285
 286         mlog(0, "Validating group descriptor %llu\n",
 287              (unsigned long long)bh->b_blocknr);
 288
 289         BUG_ON(!buffer_uptodate(bh));
 290
 291         /*
 292          * If the ecc fails, we return the error but otherwise
 293          * leave the filesystem running.  We know any error is
 294          * local to this block.
 295          */
 296         rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 297         if (rc)
 298                 return rc;
 299
 300         /*
 301          * Errors after here are fatal.
 302          */
 303
 304         return ocfs2_validate_gd_self(sb, bh, 0);
 305 }
 306
 307 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
 308                                 u64 gd_blkno, struct buffer_head **bh)
 309 {
 310         int rc;
 311         struct buffer_head *tmp = *bh;
 312
 313         rc = ocfs2_read_block(inode, gd_blkno, &tmp,
 314                               ocfs2_validate_group_descriptor);
 315         if (rc)
 316                 goto out;
 317
 318         rc = ocfs2_validate_gd_parent(inode->i_sb, di, tmp, 0);
 319         if (rc) {
 320                 brelse(tmp);
 321                 goto out;
 322         }
 323
 324         /* If ocfs2_read_block() got us a new bh, pass it up. */
 325         if (!*bh)
 326                 *bh = tmp;
 327
 328 out:
 329         return rc;
 330 }
 331
 332 static int ocfs2_block_group_fill(handle_t *handle,
 333                                   struct inode *alloc_inode,
 334                                   struct buffer_head *bg_bh,
 335                                   u64 group_blkno,
 336                                   u16 my_chain,
 337                                   struct ocfs2_chain_list *cl)
 338 {
 339         int status = 0;
 340         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 341         struct super_block * sb = alloc_inode->i_sb;
 342
 343         mlog_entry_void();
 344
 345         if (((unsigned long long) bg_bh->b_blocknr) != group_blkno) {
 346                 ocfs2_error(alloc_inode->i_sb, "group block (%llu) != "
 347                             "b_blocknr (%llu)",
 348                             (unsigned long long)group_blkno,
 349                             (unsigned long long) bg_bh->b_blocknr);
 350                 status = -EIO;
 351                 goto bail;
 352         }
 353
 354         status = ocfs2_journal_access_gd(handle,
 355                                          alloc_inode,
 356                                          bg_bh,
 357                                          OCFS2_JOURNAL_ACCESS_CREATE);
 358         if (status < 0) {
 359                 mlog_errno(status);
 360                 goto bail;
 361         }
 362
 363         memset(bg, 0, sb->s_blocksize);
 364         strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE);
 365         bg->bg_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation);
 366         bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb));
 367         bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl));
 368         bg->bg_chain = cpu_to_le16(my_chain);
 369         bg->bg_next_group = cl->cl_recs[my_chain].c_blkno;
 370         bg->bg_parent_dinode = cpu_to_le64(OCFS2_I(alloc_inode)->ip_blkno);
 371         bg->bg_blkno = cpu_to_le64(group_blkno);
 372         /* set the 1st bit in the bitmap to account for the descriptor block */
 373         ocfs2_set_bit(0, (unsigned long *)bg->bg_bitmap);
 374         bg->bg_free_bits_count = cpu_to_le16(le16_to_cpu(bg->bg_bits) - 1);
 375
 376         status = ocfs2_journal_dirty(handle, bg_bh);
 377         if (status < 0)
 378                 mlog_errno(status);
 379
 380         /* There is no need to zero out or otherwise initialize the
 381          * other blocks in a group - All valid FS metadata in a block
 382          * group stores the superblock fs_generation value at
 383          * allocation time. */
 384
 385 bail:
 386         mlog_exit(status);
 387         return status;
 388 }
 389
 390 static inline u16 ocfs2_find_smallest_chain(struct ocfs2_chain_list *cl)
 391 {
 392         u16 curr, best;
 393
 394         best = curr = 0;
 395         while (curr < le16_to_cpu(cl->cl_count)) {
 396                 if (le32_to_cpu(cl->cl_recs[best].c_total) >
 397                     le32_to_cpu(cl->cl_recs[curr].c_total))
 398                         best = curr;
 399                 curr++;
 400         }
 401         return best;
 402 }
 403
 404 /*
 405  * We expect the block group allocator to already be locked.
 406  */
 407 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
 408                                    struct inode *alloc_inode,
 409                                    struct buffer_head *bh,
 410                                    u64 max_block,
 411                                    u64 *last_alloc_group,
 412                                    int flags)
 413 {
 414         int status, credits;
 415         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bh->b_data;
 416         struct ocfs2_chain_list *cl;
 417         struct ocfs2_alloc_context *ac = NULL;
 418         handle_t *handle = NULL;
 419         u32 bit_off, num_bits;
 420         u16 alloc_rec;
 421         u64 bg_blkno;
 422         struct buffer_head *bg_bh = NULL;
 423         struct ocfs2_group_desc *bg;
 424
 425         BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
 426
 427         mlog_entry_void();
 428
 429         cl = &fe->id2.i_chain;
 430         status = ocfs2_reserve_clusters_with_limit(osb,
 431                                                    le16_to_cpu(cl->cl_cpg),
 432                                                    max_block, flags, &ac);
 433         if (status < 0) {
 434                 if (status != -ENOSPC)
 435                         mlog_errno(status);
 436                 goto bail;
 437         }
 438
 439         credits = ocfs2_calc_group_alloc_credits(osb->sb,
 440                                                  le16_to_cpu(cl->cl_cpg));
 441         handle = ocfs2_start_trans(osb, credits);
 442         if (IS_ERR(handle)) {
 443                 status = PTR_ERR(handle);
 444                 handle = NULL;
 445                 mlog_errno(status);
 446                 goto bail;
 447         }
 448
 449         if (last_alloc_group && *last_alloc_group != 0) {
 450                 mlog(0, "use old allocation group %llu for block group alloc\n",
 451                      (unsigned long long)*last_alloc_group);
 452                 ac->ac_last_group = *last_alloc_group;
 453         }
 454         status = ocfs2_claim_clusters(osb,
 455                                       handle,
 456                                       ac,
 457                                       le16_to_cpu(cl->cl_cpg),
 458                                       &bit_off,
 459                                       &num_bits);
 460         if (status < 0) {
 461                 if (status != -ENOSPC)
 462                         mlog_errno(status);
 463                 goto bail;
 464         }
 465
 466         alloc_rec = ocfs2_find_smallest_chain(cl);
 467
 468         /* setup the group */
 469         bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
 470         mlog(0, "new descriptor, record %u, at block %llu\n",
 471              alloc_rec, (unsigned long long)bg_blkno);
 472
 473         bg_bh = sb_getblk(osb->sb, bg_blkno);
 474         if (!bg_bh) {
 475                 status = -EIO;
 476                 mlog_errno(status);
 477                 goto bail;
 478         }
 479         ocfs2_set_new_buffer_uptodate(alloc_inode, bg_bh);
 480
 481         status = ocfs2_block_group_fill(handle,
 482                                         alloc_inode,
 483                                         bg_bh,
 484                                         bg_blkno,
 485                                         alloc_rec,
 486                                         cl);
 487         if (status < 0) {
 488                 mlog_errno(status);
 489                 goto bail;
 490         }
 491
 492         bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 493
 494         status = ocfs2_journal_access_di(handle, alloc_inode,
 495                                          bh, OCFS2_JOURNAL_ACCESS_WRITE);
 496         if (status < 0) {
 497                 mlog_errno(status);
 498                 goto bail;
 499         }
 500
 501         le32_add_cpu(&cl->cl_recs[alloc_rec].c_free,
 502                      le16_to_cpu(bg->bg_free_bits_count));
 503         le32_add_cpu(&cl->cl_recs[alloc_rec].c_total, le16_to_cpu(bg->bg_bits));
 504         cl->cl_recs[alloc_rec].c_blkno  = cpu_to_le64(bg_blkno);
 505         if (le16_to_cpu(cl->cl_next_free_rec) < le16_to_cpu(cl->cl_count))
 506                 le16_add_cpu(&cl->cl_next_free_rec, 1);
 507
 508         le32_add_cpu(&fe->id1.bitmap1.i_used, le16_to_cpu(bg->bg_bits) -
 509                                         le16_to_cpu(bg->bg_free_bits_count));
 510         le32_add_cpu(&fe->id1.bitmap1.i_total, le16_to_cpu(bg->bg_bits));
 511         le32_add_cpu(&fe->i_clusters, le16_to_cpu(cl->cl_cpg));
 512
 513         status = ocfs2_journal_dirty(handle, bh);
 514         if (status < 0) {
 515                 mlog_errno(status);
 516                 goto bail;
 517         }
 518
 519         spin_lock(&OCFS2_I(alloc_inode)->ip_lock);
 520         OCFS2_I(alloc_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
 521         fe->i_size = cpu_to_le64(ocfs2_clusters_to_bytes(alloc_inode->i_sb,
 522                                              le32_to_cpu(fe->i_clusters)));
 523         spin_unlock(&OCFS2_I(alloc_inode)->ip_lock);
 524         i_size_write(alloc_inode, le64_to_cpu(fe->i_size));
 525         alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode);
 526
 527         status = 0;
 528
 529         /* save the new last alloc group so that the caller can cache it. */
 530         if (last_alloc_group)
 531                 *last_alloc_group = ac->ac_last_group;
 532
 533 bail:
 534         if (handle)
 535                 ocfs2_commit_trans(osb, handle);
 536
 537         if (ac)
 538                 ocfs2_free_alloc_context(ac);
 539
 540         brelse(bg_bh);
 541
 542         mlog_exit(status);
 543         return status;
 544 }
 545
 546 static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb,
 547                                        struct ocfs2_alloc_context *ac,
 548                                        int type,
 549                                        u32 slot,
 550                                        u64 *last_alloc_group,
 551                                        int flags)
 552 {
 553         int status;
 554         u32 bits_wanted = ac->ac_bits_wanted;
 555         struct inode *alloc_inode;
 556         struct buffer_head *bh = NULL;
 557         struct ocfs2_dinode *fe;
 558         u32 free_bits;
 559
 560         mlog_entry_void();
 561
 562         alloc_inode = ocfs2_get_system_file_inode(osb, type, slot);
 563         if (!alloc_inode) {
 564                 mlog_errno(-EINVAL);
 565                 return -EINVAL;
 566         }
 567
 568         mutex_lock(&alloc_inode->i_mutex);
 569
 570         status = ocfs2_inode_lock(alloc_inode, &bh, 1);
 571         if (status < 0) {
 572                 mutex_unlock(&alloc_inode->i_mutex);
 573                 iput(alloc_inode);
 574
 575                 mlog_errno(status);
 576                 return status;
 577         }
 578
 579         ac->ac_inode = alloc_inode;
 580         ac->ac_alloc_slot = slot;
 581
 582         fe = (struct ocfs2_dinode *) bh->b_data;
 583
 584         /* The bh was validated by the inode read inside
 585          * ocfs2_inode_lock().  Any corruption is a code bug. */
 586         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
 587
 588         if (!(fe->i_flags & cpu_to_le32(OCFS2_CHAIN_FL))) {
 589                 ocfs2_error(alloc_inode->i_sb, "Invalid chain allocator %llu",
 590                             (unsigned long long)le64_to_cpu(fe->i_blkno));
 591                 status = -EIO;
 592                 goto bail;
 593         }
 594
 595         free_bits = le32_to_cpu(fe->id1.bitmap1.i_total) -
 596                 le32_to_cpu(fe->id1.bitmap1.i_used);
 597
 598         if (bits_wanted > free_bits) {
 599                 /* cluster bitmap never grows */
 600                 if (ocfs2_is_cluster_bitmap(alloc_inode)) {
 601                         mlog(0, "Disk Full: wanted=%u, free_bits=%u\n",
 602                              bits_wanted, free_bits);
 603                         status = -ENOSPC;
 604                         goto bail;
 605                 }
 606
 607                 if (!(flags & ALLOC_NEW_GROUP)) {
 608                         mlog(0, "Alloc File %u Full: wanted=%u, free_bits=%u, "
 609                              "and we don't alloc a new group for it.\n",
 610                              slot, bits_wanted, free_bits);
 611                         status = -ENOSPC;
 612                         goto bail;
 613                 }
 614
 615                 status = ocfs2_block_group_alloc(osb, alloc_inode, bh,
 616                                                  ac->ac_max_block,
 617                                                  last_alloc_group, flags);
 618                 if (status < 0) {
 619                         if (status != -ENOSPC)
 620                                 mlog_errno(status);
 621                         goto bail;
 622                 }
 623                 atomic_inc(&osb->alloc_stats.bg_extends);
 624
 625                 /* You should never ask for this much metadata */
 626                 BUG_ON(bits_wanted >
 627                        (le32_to_cpu(fe->id1.bitmap1.i_total)
 628                         - le32_to_cpu(fe->id1.bitmap1.i_used)));
 629         }
 630
 631         get_bh(bh);
 632         ac->ac_bh = bh;
 633 bail:
 634         brelse(bh);
 635
 636         mlog_exit(status);
 637         return status;
 638 }
 639
 640 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
 641                                       int blocks,
 642                                       struct ocfs2_alloc_context **ac)
 643 {
 644         int status;
 645         u32 slot;
 646
 647         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 648         if (!(*ac)) {
 649                 status = -ENOMEM;
 650                 mlog_errno(status);
 651                 goto bail;
 652         }
 653
 654         (*ac)->ac_bits_wanted = blocks;
 655         (*ac)->ac_which = OCFS2_AC_USE_META;
 656         slot = osb->slot_num;
 657         (*ac)->ac_group_search = ocfs2_block_group_search;
 658
 659         status = ocfs2_reserve_suballoc_bits(osb, (*ac),
 660                                              EXTENT_ALLOC_SYSTEM_INODE,
 661                                              slot, NULL, ALLOC_NEW_GROUP);
 662         if (status < 0) {
 663                 if (status != -ENOSPC)
 664                         mlog_errno(status);
 665                 goto bail;
 666         }
 667
 668         status = 0;
 669 bail:
 670         if ((status < 0) && *ac) {
 671                 ocfs2_free_alloc_context(*ac);
 672                 *ac = NULL;
 673         }
 674
 675         mlog_exit(status);
 676         return status;
 677 }
 678
 679 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
 680                                struct ocfs2_extent_list *root_el,
 681                                struct ocfs2_alloc_context **ac)
 682 {
 683         return ocfs2_reserve_new_metadata_blocks(osb,
 684                                         ocfs2_extend_meta_needed(root_el),
 685                                         ac);
 686 }
 687
 688 static int ocfs2_steal_inode_from_other_nodes(struct ocfs2_super *osb,
 689                                               struct ocfs2_alloc_context *ac)
 690 {
 691         int i, status = -ENOSPC;
 692         s16 slot = ocfs2_get_inode_steal_slot(osb);
 693
 694         /* Start to steal inodes from the first slot after ours. */
 695         if (slot == OCFS2_INVALID_SLOT)
 696                 slot = osb->slot_num + 1;
 697
 698         for (i = 0; i < osb->max_slots; i++, slot++) {
 699                 if (slot == osb->max_slots)
 700                         slot = 0;
 701
 702                 if (slot == osb->slot_num)
 703                         continue;
 704
 705                 status = ocfs2_reserve_suballoc_bits(osb, ac,
 706                                                      INODE_ALLOC_SYSTEM_INODE,
 707                                                      slot, NULL,
 708                                                      NOT_ALLOC_NEW_GROUP);
 709                 if (status >= 0) {
 710                         ocfs2_set_inode_steal_slot(osb, slot);
 711                         break;
 712                 }
 713
 714                 ocfs2_free_ac_resource(ac);
 715         }
 716
 717         return status;
 718 }
 719
 720 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
 721                             struct ocfs2_alloc_context **ac)
 722 {
 723         int status;
 724         s16 slot = ocfs2_get_inode_steal_slot(osb);
 725         u64 alloc_group;
 726
 727         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 728         if (!(*ac)) {
 729                 status = -ENOMEM;
 730                 mlog_errno(status);
 731                 goto bail;
 732         }
 733
 734         (*ac)->ac_bits_wanted = 1;
 735         (*ac)->ac_which = OCFS2_AC_USE_INODE;
 736
 737         (*ac)->ac_group_search = ocfs2_block_group_search;
 738
 739         /*
 740          * stat(2) can't handle i_ino > 32bits, so we tell the
 741          * lower levels not to allocate us a block group past that
 742          * limit.  The 'inode64' mount option avoids this behavior.
 743          */
 744         if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64))
 745                 (*ac)->ac_max_block = (u32)~0U;
 746
 747         /*
 748          * slot is set when we successfully steal inode from other nodes.
 749          * It is reset in 3 places:
 750          * 1. when we flush the truncate log
 751          * 2. when we complete local alloc recovery.
 752          * 3. when we successfully allocate from our own slot.
 753          * After it is set, we will go on stealing inodes until we find the
 754          * need to check our slots to see whether there is some space for us.
 755          */
 756         if (slot != OCFS2_INVALID_SLOT &&
 757             atomic_read(&osb->s_num_inodes_stolen) < OCFS2_MAX_INODES_TO_STEAL)
 758                 goto inode_steal;
 759
 760         atomic_set(&osb->s_num_inodes_stolen, 0);
 761         alloc_group = osb->osb_inode_alloc_group;
 762         status = ocfs2_reserve_suballoc_bits(osb, *ac,
 763                                              INODE_ALLOC_SYSTEM_INODE,
 764                                              osb->slot_num,
 765                                              &alloc_group,
 766                                              ALLOC_NEW_GROUP |
 767                                              ALLOC_GROUPS_FROM_GLOBAL);
 768         if (status >= 0) {
 769                 status = 0;
 770
 771                 spin_lock(&osb->osb_lock);
 772                 osb->osb_inode_alloc_group = alloc_group;
 773                 spin_unlock(&osb->osb_lock);
 774                 mlog(0, "after reservation, new allocation group is "
 775                      "%llu\n", (unsigned long long)alloc_group);
 776
 777                 /*
 778                  * Some inodes must be freed by us, so try to allocate
 779                  * from our own next time.
 780                  */
 781                 if (slot != OCFS2_INVALID_SLOT)
 782                         ocfs2_init_inode_steal_slot(osb);
 783                 goto bail;
 784         } else if (status < 0 && status != -ENOSPC) {
 785                 mlog_errno(status);
 786                 goto bail;
 787         }
 788
 789         ocfs2_free_ac_resource(*ac);
 790
 791 inode_steal:
 792         status = ocfs2_steal_inode_from_other_nodes(osb, *ac);
 793         atomic_inc(&osb->s_num_inodes_stolen);
 794         if (status < 0) {
 795                 if (status != -ENOSPC)
 796                         mlog_errno(status);
 797                 goto bail;
 798         }
 799
 800         status = 0;
 801 bail:
 802         if ((status < 0) && *ac) {
 803                 ocfs2_free_alloc_context(*ac);
 804                 *ac = NULL;
 805         }
 806
 807         mlog_exit(status);
 808         return status;
 809 }
 810
 811 /* local alloc code has to do the same thing, so rather than do this
 812  * twice.. */
 813 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
 814                                       struct ocfs2_alloc_context *ac)
 815 {
 816         int status;
 817
 818         ac->ac_which = OCFS2_AC_USE_MAIN;
 819         ac->ac_group_search = ocfs2_cluster_group_search;
 820
 821         status = ocfs2_reserve_suballoc_bits(osb, ac,
 822                                              GLOBAL_BITMAP_SYSTEM_INODE,
 823                                              OCFS2_INVALID_SLOT, NULL,
 824                                              ALLOC_NEW_GROUP);
 825         if (status < 0 && status != -ENOSPC) {
 826                 mlog_errno(status);
 827                 goto bail;
 828         }
 829
 830 bail:
 831         return status;
 832 }
 833
 834 /* Callers don't need to care which bitmap (local alloc or main) to
 835  * use so we figure it out for them, but unfortunately this clutters
 836  * things a bit. */
 837 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
 838                                              u32 bits_wanted, u64 max_block,
 839                                              int flags,
 840                                              struct ocfs2_alloc_context **ac)
 841 {
 842         int status;
 843
 844         mlog_entry_void();
 845
 846         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 847         if (!(*ac)) {
 848                 status = -ENOMEM;
 849                 mlog_errno(status);
 850                 goto bail;
 851         }
 852
 853         (*ac)->ac_bits_wanted = bits_wanted;
 854         (*ac)->ac_max_block = max_block;
 855
 856         status = -ENOSPC;
 857         if (!(flags & ALLOC_GROUPS_FROM_GLOBAL) &&
 858             ocfs2_alloc_should_use_local(osb, bits_wanted)) {
 859                 status = ocfs2_reserve_local_alloc_bits(osb,
 860                                                         bits_wanted,
 861                                                         *ac);
 862                 if (status == -EFBIG) {
 863                         /* The local alloc window is outside ac_max_block.
 864                          * use the main bitmap. */
 865                         status = -ENOSPC;
 866                 } else if ((status < 0) && (status != -ENOSPC)) {
 867                         mlog_errno(status);
 868                         goto bail;
 869                 }
 870         }
 871
 872         if (status == -ENOSPC) {
 873                 status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
 874                 if (status < 0) {
 875                         if (status != -ENOSPC)
 876                                 mlog_errno(status);
 877                         goto bail;
 878                 }
 879         }
 880
 881         status = 0;
 882 bail:
 883         if ((status < 0) && *ac) {
 884                 ocfs2_free_alloc_context(*ac);
 885                 *ac = NULL;
 886         }
 887
 888         mlog_exit(status);
 889         return status;
 890 }
 891
 892 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
 893                            u32 bits_wanted,
 894                            struct ocfs2_alloc_context **ac)
 895 {
 896         return ocfs2_reserve_clusters_with_limit(osb, bits_wanted, 0,
 897                                                  ALLOC_NEW_GROUP, ac);
 898 }
 899
 900 /*
 901  * More or less lifted from ext3. I'll leave their description below:
 902  *
 903  * "For ext3 allocations, we must not reuse any blocks which are
 904  * allocated in the bitmap buffer's "last committed data" copy.  This
 905  * prevents deletes from freeing up the page for reuse until we have
 906  * committed the delete transaction.
 907  *
 908  * If we didn't do this, then deleting something and reallocating it as
 909  * data would allow the old block to be overwritten before the
 910  * transaction committed (because we force data to disk before commit).
 911  * This would lead to corruption if we crashed between overwriting the
 912  * data and committing the delete.
 913  *
 914  * @@@ We may want to make this allocation behaviour conditional on
 915  * data-writes at some point, and disable it for metadata allocations or
 916  * sync-data inodes."
 917  *
 918  * Note: OCFS2 already does this differently for metadata vs data
 919  * allocations, as those bitmaps are separate and undo access is never
 920  * called on a metadata group descriptor.
 921  */
 922 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
 923                                          int nr)
 924 {
 925         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 926         int ret;
 927
 928         if (ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap))
 929                 return 0;
 930
 931         if (!buffer_jbd(bg_bh))
 932                 return 1;
 933
 934         jbd_lock_bh_state(bg_bh);
 935         bg = (struct ocfs2_group_desc *) bh2jh(bg_bh)->b_committed_data;
 936         if (bg)
 937                 ret = !ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap);
 938         else
 939                 ret = 1;
 940         jbd_unlock_bh_state(bg_bh);
 941
 942         return ret;
 943 }
 944
 945 static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
 946                                              struct buffer_head *bg_bh,
 947                                              unsigned int bits_wanted,
 948                                              unsigned int total_bits,
 949                                              u16 *bit_off,
 950                                              u16 *bits_found)
 951 {
 952         void *bitmap;
 953         u16 best_offset, best_size;
 954         int offset, start, found, status = 0;
 955         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 956
 957         /* Callers got this descriptor from
 958          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
 959         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
 960
 961         found = start = best_offset = best_size = 0;
 962         bitmap = bg->bg_bitmap;
 963
 964         while((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) != -1) {
 965                 if (offset == total_bits)
 966                         break;
 967
 968                 if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) {
 969                         /* We found a zero, but we can't use it as it
 970                          * hasn't been put to disk yet! */
 971                         found = 0;
 972                         start = offset + 1;
 973                 } else if (offset == start) {
 974                         /* we found a zero */
 975                         found++;
 976                         /* move start to the next bit to test */
 977                         start++;
 978                 } else {
 979                         /* got a zero after some ones */
 980                         found = 1;
 981                         start = offset + 1;
 982                 }
 983                 if (found > best_size) {
 984                         best_size = found;
 985                         best_offset = start - found;
 986                 }
 987                 /* we got everything we needed */
 988                 if (found == bits_wanted) {
 989                         /* mlog(0, "Found it all!\n"); */
 990                         break;
 991                 }
 992         }
 993
 994         /* XXX: I think the first clause is equivalent to the second
 995          *      - jlbec */
 996         if (found == bits_wanted) {
 997                 *bit_off = start - found;
 998                 *bits_found = found;
 999         } else if (best_size) {
1000                 *bit_off = best_offset;
1001                 *bits_found = best_size;
1002         } else {
1003                 status = -ENOSPC;
1004                 /* No error log here -- see the comment above
1005                  * ocfs2_test_bg_bit_allocatable */
1006         }
1007
1008         return status;
1009 }
1010
1011 static inline int ocfs2_block_group_set_bits(handle_t *handle,
1012                                              struct inode *alloc_inode,
1013                                              struct ocfs2_group_desc *bg,
1014                                              struct buffer_head *group_bh,
1015                                              unsigned int bit_off,
1016                                              unsigned int num_bits)
1017 {
1018         int status;
1019         void *bitmap = bg->bg_bitmap;
1020         int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
1021
1022         mlog_entry_void();
1023
1024         /* All callers get the descriptor via
1025          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1026         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1027         BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
1028
1029         mlog(0, "block_group_set_bits: off = %u, num = %u\n", bit_off,
1030              num_bits);
1031
1032         if (ocfs2_is_cluster_bitmap(alloc_inode))
1033                 journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
1034
1035         status = ocfs2_journal_access_gd(handle,
1036                                          alloc_inode,
1037                                          group_bh,
1038                                          journal_type);
1039         if (status < 0) {
1040                 mlog_errno(status);
1041                 goto bail;
1042         }
1043
1044         le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
1045
1046         while(num_bits--)
1047                 ocfs2_set_bit(bit_off++, bitmap);
1048
1049         status = ocfs2_journal_dirty(handle,
1050                                      group_bh);
1051         if (status < 0) {
1052                 mlog_errno(status);
1053                 goto bail;
1054         }
1055
1056 bail:
1057         mlog_exit(status);
1058         return status;
1059 }
1060
1061 /* find the one with the most empty bits */
1062 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl)
1063 {
1064         u16 curr, best;
1065
1066         BUG_ON(!cl->cl_next_free_rec);
1067
1068         best = curr = 0;
1069         while (curr < le16_to_cpu(cl->cl_next_free_rec)) {
1070                 if (le32_to_cpu(cl->cl_recs[curr].c_free) >
1071                     le32_to_cpu(cl->cl_recs[best].c_free))
1072                         best = curr;
1073                 curr++;
1074         }
1075
1076         BUG_ON(best >= le16_to_cpu(cl->cl_next_free_rec));
1077         return best;
1078 }
1079
1080 static int ocfs2_relink_block_group(handle_t *handle,
1081                                     struct inode *alloc_inode,
1082                                     struct buffer_head *fe_bh,
1083                                     struct buffer_head *bg_bh,
1084                                     struct buffer_head *prev_bg_bh,
1085                                     u16 chain)
1086 {
1087         int status;
1088         /* there is a really tiny chance the journal calls could fail,
1089          * but we wouldn't want inconsistent blocks in *any* case. */
1090         u64 fe_ptr, bg_ptr, prev_bg_ptr;
1091         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
1092         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1093         struct ocfs2_group_desc *prev_bg = (struct ocfs2_group_desc *) prev_bg_bh->b_data;
1094
1095         /* The caller got these descriptors from
1096          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1097         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1098         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(prev_bg));
1099
1100         mlog(0, "Suballoc %llu, chain %u, move group %llu to top, prev = %llu\n",
1101              (unsigned long long)le64_to_cpu(fe->i_blkno), chain,
1102              (unsigned long long)le64_to_cpu(bg->bg_blkno),
1103              (unsigned long long)le64_to_cpu(prev_bg->bg_blkno));
1104
1105         fe_ptr = le64_to_cpu(fe->id2.i_chain.cl_recs[chain].c_blkno);
1106         bg_ptr = le64_to_cpu(bg->bg_next_group);
1107         prev_bg_ptr = le64_to_cpu(prev_bg->bg_next_group);
1108
1109         status = ocfs2_journal_access_gd(handle, alloc_inode, prev_bg_bh,
1110                                          OCFS2_JOURNAL_ACCESS_WRITE);
1111         if (status < 0) {
1112                 mlog_errno(status);
1113                 goto out_rollback;
1114         }
1115
1116         prev_bg->bg_next_group = bg->bg_next_group;
1117
1118         status = ocfs2_journal_dirty(handle, prev_bg_bh);
1119         if (status < 0) {
1120                 mlog_errno(status);
1121                 goto out_rollback;
1122         }
1123
1124         status = ocfs2_journal_access_gd(handle, alloc_inode, bg_bh,
1125                                          OCFS2_JOURNAL_ACCESS_WRITE);
1126         if (status < 0) {
1127                 mlog_errno(status);
1128                 goto out_rollback;
1129         }
1130
1131         bg->bg_next_group = fe->id2.i_chain.cl_recs[chain].c_blkno;
1132
1133         status = ocfs2_journal_dirty(handle, bg_bh);
1134         if (status < 0) {
1135                 mlog_errno(status);
1136                 goto out_rollback;
1137         }
1138
1139         status = ocfs2_journal_access_di(handle, alloc_inode, fe_bh,
1140                                          OCFS2_JOURNAL_ACCESS_WRITE);
1141         if (status < 0) {
1142                 mlog_errno(status);
1143                 goto out_rollback;
1144         }
1145
1146         fe->id2.i_chain.cl_recs[chain].c_blkno = bg->bg_blkno;
1147
1148         status = ocfs2_journal_dirty(handle, fe_bh);
1149         if (status < 0) {
1150                 mlog_errno(status);
1151                 goto out_rollback;
1152         }
1153
1154         status = 0;
1155 out_rollback:
1156         if (status < 0) {
1157                 fe->id2.i_chain.cl_recs[chain].c_blkno = cpu_to_le64(fe_ptr);
1158                 bg->bg_next_group = cpu_to_le64(bg_ptr);
1159                 prev_bg->bg_next_group = cpu_to_le64(prev_bg_ptr);
1160         }
1161
1162         mlog_exit(status);
1163         return status;
1164 }
1165
1166 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
1167                                                      u32 wanted)
1168 {
1169         return le16_to_cpu(bg->bg_free_bits_count) > wanted;
1170 }
1171
1172 /* return 0 on success, -ENOSPC to keep searching and any other < 0
1173  * value on error. */
1174 static int ocfs2_cluster_group_search(struct inode *inode,
1175                                       struct buffer_head *group_bh,
1176                                       u32 bits_wanted, u32 min_bits,
1177                                       u64 max_block,
1178                                       u16 *bit_off, u16 *bits_found)
1179 {
1180         int search = -ENOSPC;
1181         int ret;
1182         u64 blkoff;
1183         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *) group_bh->b_data;
1184         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1185         u16 tmp_off, tmp_found;
1186         unsigned int max_bits, gd_cluster_off;
1187
1188         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1189
1190         if (gd->bg_free_bits_count) {
1191                 max_bits = le16_to_cpu(gd->bg_bits);
1192
1193                 /* Tail groups in cluster bitmaps which aren't cpg
1194                  * aligned are prone to partial extention by a failed
1195                  * fs resize. If the file system resize never got to
1196                  * update the dinode cluster count, then we don't want
1197                  * to trust any clusters past it, regardless of what
1198                  * the group descriptor says. */
1199                 gd_cluster_off = ocfs2_blocks_to_clusters(inode->i_sb,
1200                                                           le64_to_cpu(gd->bg_blkno));
1201                 if ((gd_cluster_off + max_bits) >
1202                     OCFS2_I(inode)->ip_clusters) {
1203                         max_bits = OCFS2_I(inode)->ip_clusters - gd_cluster_off;
1204                         mlog(0, "Desc %llu, bg_bits %u, clusters %u, use %u\n",
1205                              (unsigned long long)le64_to_cpu(gd->bg_blkno),
1206                              le16_to_cpu(gd->bg_bits),
1207                              OCFS2_I(inode)->ip_clusters, max_bits);
1208                 }
1209
1210                 ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1211                                                         group_bh, bits_wanted,
1212                                                         max_bits,
1213                                                         &tmp_off, &tmp_found);
1214                 if (ret)
1215                         return ret;
1216
1217                 if (max_block) {
1218                         blkoff = ocfs2_clusters_to_blocks(inode->i_sb,
1219                                                           gd_cluster_off +
1220                                                           tmp_off + tmp_found);
1221                         mlog(0, "Checking %llu against %llu\n",
1222                              (unsigned long long)blkoff,
1223                              (unsigned long long)max_block);
1224                         if (blkoff > max_block)
1225                                 return -ENOSPC;
1226                 }
1227
1228                 /* ocfs2_block_group_find_clear_bits() might
1229                  * return success, but we still want to return
1230                  * -ENOSPC unless it found the minimum number
1231                  * of bits. */
1232                 if (min_bits <= tmp_found) {
1233                         *bit_off = tmp_off;
1234                         *bits_found = tmp_found;
1235                         search = 0; /* success */
1236                 } else if (tmp_found) {
1237                         /*
1238                          * Don't show bits which we'll be returning
1239                          * for allocation to the local alloc bitmap.
1240                          */
1241                         ocfs2_local_alloc_seen_free_bits(osb, tmp_found);
1242                 }
1243         }
1244
1245         return search;
1246 }
1247
1248 static int ocfs2_block_group_search(struct inode *inode,
1249                                     struct buffer_head *group_bh,
1250                                     u32 bits_wanted, u32 min_bits,
1251                                     u64 max_block,
1252                                     u16 *bit_off, u16 *bits_found)
1253 {
1254         int ret = -ENOSPC;
1255         u64 blkoff;
1256         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) group_bh->b_data;
1257
1258         BUG_ON(min_bits != 1);
1259         BUG_ON(ocfs2_is_cluster_bitmap(inode));
1260
1261         if (bg->bg_free_bits_count) {
1262                 ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1263                                                         group_bh, bits_wanted,
1264                                                         le16_to_cpu(bg->bg_bits),
1265                                                         bit_off, bits_found);
1266                 if (!ret && max_block) {
1267                         blkoff = le64_to_cpu(bg->bg_blkno) + *bit_off +
1268                                 *bits_found;
1269                         mlog(0, "Checking %llu against %llu\n",
1270                              (unsigned long long)blkoff,
1271                              (unsigned long long)max_block);
1272                         if (blkoff > max_block)
1273                                 ret = -ENOSPC;
1274                 }
1275         }
1276
1277         return ret;
1278 }
1279
1280 static int ocfs2_alloc_dinode_update_counts(struct inode *inode,
1281                                        handle_t *handle,
1282                                        struct buffer_head *di_bh,
1283                                        u32 num_bits,
1284                                        u16 chain)
1285 {
1286         int ret;
1287         u32 tmp_used;
1288         struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1289         struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &di->id2.i_chain;
1290
1291         ret = ocfs2_journal_access_di(handle, inode, di_bh,
1292                                       OCFS2_JOURNAL_ACCESS_WRITE);
1293         if (ret < 0) {
1294                 mlog_errno(ret);
1295                 goto out;
1296         }
1297
1298         tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1299         di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
1300         le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
1301
1302         ret = ocfs2_journal_dirty(handle, di_bh);
1303         if (ret < 0)
1304                 mlog_errno(ret);
1305
1306 out:
1307         return ret;
1308 }
1309
1310 static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
1311                                   handle_t *handle,
1312                                   u32 bits_wanted,
1313                                   u32 min_bits,
1314                                   u16 *bit_off,
1315                                   unsigned int *num_bits,
1316                                   u64 gd_blkno,
1317                                   u16 *bits_left)
1318 {
1319         int ret;
1320         u16 found;
1321         struct buffer_head *group_bh = NULL;
1322         struct ocfs2_group_desc *gd;
1323         struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1324         struct inode *alloc_inode = ac->ac_inode;
1325
1326         ret = ocfs2_read_group_descriptor(alloc_inode, di, gd_blkno,
1327                                           &group_bh);
1328         if (ret < 0) {
1329                 mlog_errno(ret);
1330                 return ret;
1331         }
1332
1333         gd = (struct ocfs2_group_desc *) group_bh->b_data;
1334         ret = ac->ac_group_search(alloc_inode, group_bh, bits_wanted, min_bits,
1335                                   ac->ac_max_block, bit_off, &found);
1336         if (ret < 0) {
1337                 if (ret != -ENOSPC)
1338                         mlog_errno(ret);
1339                 goto out;
1340         }
1341
1342         *num_bits = found;
1343
1344         ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
1345                                                *num_bits,
1346                                                le16_to_cpu(gd->bg_chain));
1347         if (ret < 0) {
1348                 mlog_errno(ret);
1349                 goto out;
1350         }
1351
1352         ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
1353                                          *bit_off, *num_bits);
1354         if (ret < 0)
1355                 mlog_errno(ret);
1356
1357         *bits_left = le16_to_cpu(gd->bg_free_bits_count);
1358
1359 out:
1360         brelse(group_bh);
1361
1362         return ret;
1363 }
1364
1365 static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
1366                               handle_t *handle,
1367                               u32 bits_wanted,
1368                               u32 min_bits,
1369                               u16 *bit_off,
1370                               unsigned int *num_bits,
1371                               u64 *bg_blkno,
1372                               u16 *bits_left)
1373 {
1374         int status;
1375         u16 chain, tmp_bits;
1376         u32 tmp_used;
1377         u64 next_group;
1378         struct inode *alloc_inode = ac->ac_inode;
1379         struct buffer_head *group_bh = NULL;
1380         struct buffer_head *prev_group_bh = NULL;
1381         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1382         struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1383         struct ocfs2_group_desc *bg;
1384
1385         chain = ac->ac_chain;
1386         mlog(0, "trying to alloc %u bits from chain %u, inode %llu\n",
1387              bits_wanted, chain,
1388              (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno);
1389
1390         status = ocfs2_read_group_descriptor(alloc_inode, fe,
1391                                              le64_to_cpu(cl->cl_recs[chain].c_blkno),
1392                                              &group_bh);
1393         if (status < 0) {
1394                 mlog_errno(status);
1395                 goto bail;
1396         }
1397         bg = (struct ocfs2_group_desc *) group_bh->b_data;
1398
1399         status = -ENOSPC;
1400         /* for now, the chain search is a bit simplistic. We just use
1401          * the 1st group with any empty bits. */
1402         while ((status = ac->ac_group_search(alloc_inode, group_bh,
1403                                              bits_wanted, min_bits,
1404                                              ac->ac_max_block, bit_off,
1405                                              &tmp_bits)) == -ENOSPC) {
1406                 if (!bg->bg_next_group)
1407                         break;
1408
1409                 brelse(prev_group_bh);
1410                 prev_group_bh = NULL;
1411
1412                 next_group = le64_to_cpu(bg->bg_next_group);
1413                 prev_group_bh = group_bh;
1414                 group_bh = NULL;
1415                 status = ocfs2_read_group_descriptor(alloc_inode, fe,
1416                                                      next_group, &group_bh);
1417                 if (status < 0) {
1418                         mlog_errno(status);
1419                         goto bail;
1420                 }
1421                 bg = (struct ocfs2_group_desc *) group_bh->b_data;
1422         }
1423         if (status < 0) {
1424                 if (status != -ENOSPC)
1425                         mlog_errno(status);
1426                 goto bail;
1427         }
1428
1429         mlog(0, "alloc succeeds: we give %u bits from block group %llu\n",
1430              tmp_bits, (unsigned long long)le64_to_cpu(bg->bg_blkno));
1431
1432         *num_bits = tmp_bits;
1433
1434         BUG_ON(*num_bits == 0);
1435
1436         /*
1437          * Keep track of previous block descriptor read. When
1438          * we find a target, if we have read more than X
1439          * number of descriptors, and the target is reasonably
1440          * empty, relink him to top of his chain.
1441          *
1442          * We've read 0 extra blocks and only send one more to
1443          * the transaction, yet the next guy to search has a
1444          * much easier time.
1445          *
1446          * Do this *after* figuring out how many bits we're taking out
1447          * of our target group.
1448          */
1449         if (ac->ac_allow_chain_relink &&
1450             (prev_group_bh) &&
1451             (ocfs2_block_group_reasonably_empty(bg, *num_bits))) {
1452                 status = ocfs2_relink_block_group(handle, alloc_inode,
1453                                                   ac->ac_bh, group_bh,
1454                                                   prev_group_bh, chain);
1455                 if (status < 0) {
1456                         mlog_errno(status);
1457                         goto bail;
1458                 }
1459         }
1460
1461         /* Ok, claim our bits now: set the info on dinode, chainlist
1462          * and then the group */
1463         status = ocfs2_journal_access_di(handle,
1464                                          alloc_inode,
1465                                          ac->ac_bh,
1466                                          OCFS2_JOURNAL_ACCESS_WRITE);
1467         if (status < 0) {
1468                 mlog_errno(status);
1469                 goto bail;
1470         }
1471
1472         tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
1473         fe->id1.bitmap1.i_used = cpu_to_le32(*num_bits + tmp_used);
1474         le32_add_cpu(&cl->cl_recs[chain].c_free, -(*num_bits));
1475
1476         status = ocfs2_journal_dirty(handle,
1477                                      ac->ac_bh);
1478         if (status < 0) {
1479                 mlog_errno(status);
1480                 goto bail;
1481         }
1482
1483         status = ocfs2_block_group_set_bits(handle,
1484                                             alloc_inode,
1485                                             bg,
1486                                             group_bh,
1487                                             *bit_off,
1488                                             *num_bits);
1489         if (status < 0) {
1490                 mlog_errno(status);
1491                 goto bail;
1492         }
1493
1494         mlog(0, "Allocated %u bits from suballocator %llu\n", *num_bits,
1495              (unsigned long long)le64_to_cpu(fe->i_blkno));
1496
1497         *bg_blkno = le64_to_cpu(bg->bg_blkno);
1498         *bits_left = le16_to_cpu(bg->bg_free_bits_count);
1499 bail:
1500         brelse(group_bh);
1501         brelse(prev_group_bh);
1502
1503         mlog_exit(status);
1504         return status;
1505 }
1506
1507 /* will give out up to bits_wanted contiguous bits. */
1508 static int ocfs2_claim_suballoc_bits(struct ocfs2_super *osb,
1509                                      struct ocfs2_alloc_context *ac,
1510                                      handle_t *handle,
1511                                      u32 bits_wanted,
1512                                      u32 min_bits,
1513                                      u16 *bit_off,
1514                                      unsigned int *num_bits,
1515                                      u64 *bg_blkno)
1516 {
1517         int status;
1518         u16 victim, i;
1519         u16 bits_left = 0;
1520         u64 hint_blkno = ac->ac_last_group;
1521         struct ocfs2_chain_list *cl;
1522         struct ocfs2_dinode *fe;
1523
1524         mlog_entry_void();
1525
1526         BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1527         BUG_ON(bits_wanted > (ac->ac_bits_wanted - ac->ac_bits_given));
1528         BUG_ON(!ac->ac_bh);
1529
1530         fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1531
1532         /* The bh was validated by the inode read during
1533          * ocfs2_reserve_suballoc_bits().  Any corruption is a code bug. */
1534         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1535
1536         if (le32_to_cpu(fe->id1.bitmap1.i_used) >=
1537             le32_to_cpu(fe->id1.bitmap1.i_total)) {
1538                 ocfs2_error(osb->sb, "Chain allocator dinode %llu has %u used "
1539                             "bits but only %u total.",
1540                             (unsigned long long)le64_to_cpu(fe->i_blkno),
1541                             le32_to_cpu(fe->id1.bitmap1.i_used),
1542                             le32_to_cpu(fe->id1.bitmap1.i_total));
1543                 status = -EIO;
1544                 goto bail;
1545         }
1546
1547         if (hint_blkno) {
1548                 /* Attempt to short-circuit the usual search mechanism
1549                  * by jumping straight to the most recently used
1550                  * allocation group. This helps us mantain some
1551                  * contiguousness across allocations. */
1552                 status = ocfs2_search_one_group(ac, handle, bits_wanted,
1553                                                 min_bits, bit_off, num_bits,
1554                                                 hint_blkno, &bits_left);
1555                 if (!status) {
1556                         /* Be careful to update *bg_blkno here as the
1557                          * caller is expecting it to be filled in, and
1558                          * ocfs2_search_one_group() won't do that for
1559                          * us. */
1560                         *bg_blkno = hint_blkno;
1561                         goto set_hint;
1562                 }
1563                 if (status < 0 && status != -ENOSPC) {
1564                         mlog_errno(status);
1565                         goto bail;
1566                 }
1567         }
1568
1569         cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1570
1571         victim = ocfs2_find_victim_chain(cl);
1572         ac->ac_chain = victim;
1573         ac->ac_allow_chain_relink = 1;
1574
1575         status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits, bit_off,
1576                                     num_bits, bg_blkno, &bits_left);
1577         if (!status)
1578                 goto set_hint;
1579         if (status < 0 && status != -ENOSPC) {
1580                 mlog_errno(status);
1581                 goto bail;
1582         }
1583
1584         mlog(0, "Search of victim chain %u came up with nothing, "
1585              "trying all chains now.\n", victim);
1586
1587         /* If we didn't pick a good victim, then just default to
1588          * searching each chain in order. Don't allow chain relinking
1589          * because we only calculate enough journal credits for one
1590          * relink per alloc. */
1591         ac->ac_allow_chain_relink = 0;
1592         for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
1593                 if (i == victim)
1594                         continue;
1595                 if (!cl->cl_recs[i].c_free)
1596                         continue;
1597
1598                 ac->ac_chain = i;
1599                 status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1600                                             bit_off, num_bits, bg_blkno,
1601                                             &bits_left);
1602                 if (!status)
1603                         break;
1604                 if (status < 0 && status != -ENOSPC) {
1605                         mlog_errno(status);
1606                         goto bail;
1607                 }
1608         }
1609
1610 set_hint:
1611         if (status != -ENOSPC) {
1612                 /* If the next search of this group is not likely to
1613                  * yield a suitable extent, then we reset the last
1614                  * group hint so as to not waste a disk read */
1615                 if (bits_left < min_bits)
1616                         ac->ac_last_group = 0;
1617                 else
1618                         ac->ac_last_group = *bg_blkno;
1619         }
1620
1621 bail:
1622         mlog_exit(status);
1623         return status;
1624 }
1625
1626 int ocfs2_claim_metadata(struct ocfs2_super *osb,
1627                          handle_t *handle,
1628                          struct ocfs2_alloc_context *ac,
1629                          u32 bits_wanted,
1630                          u16 *suballoc_bit_start,
1631                          unsigned int *num_bits,
1632                          u64 *blkno_start)
1633 {
1634         int status;
1635         u64 bg_blkno;
1636
1637         BUG_ON(!ac);
1638         BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
1639         BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
1640
1641         status = ocfs2_claim_suballoc_bits(osb,
1642                                            ac,
1643                                            handle,
1644                                            bits_wanted,
1645                                            1,
1646                                            suballoc_bit_start,
1647                                            num_bits,
1648                                            &bg_blkno);
1649         if (status < 0) {
1650                 mlog_errno(status);
1651                 goto bail;
1652         }
1653         atomic_inc(&osb->alloc_stats.bg_allocs);
1654
1655         *blkno_start = bg_blkno + (u64) *suballoc_bit_start;
1656         ac->ac_bits_given += (*num_bits);
1657         status = 0;
1658 bail:
1659         mlog_exit(status);
1660         return status;
1661 }
1662
1663 static void ocfs2_init_inode_ac_group(struct inode *dir,
1664                                       struct buffer_head *parent_fe_bh,
1665                                       struct ocfs2_alloc_context *ac)
1666 {
1667         struct ocfs2_dinode *fe = (struct ocfs2_dinode *)parent_fe_bh->b_data;
1668         /*
1669          * Try to allocate inodes from some specific group.
1670          *
1671          * If the parent dir has recorded the last group used in allocation,
1672          * cool, use it. Otherwise if we try to allocate new inode from the
1673          * same slot the parent dir belongs to, use the same chunk.
1674          *
1675          * We are very careful here to avoid the mistake of setting
1676          * ac_last_group to a group descriptor from a different (unlocked) slot.
1677          */
1678         if (OCFS2_I(dir)->ip_last_used_group &&
1679             OCFS2_I(dir)->ip_last_used_slot == ac->ac_alloc_slot)
1680                 ac->ac_last_group = OCFS2_I(dir)->ip_last_used_group;
1681         else if (le16_to_cpu(fe->i_suballoc_slot) == ac->ac_alloc_slot)
1682                 ac->ac_last_group = ocfs2_which_suballoc_group(
1683                                         le64_to_cpu(fe->i_blkno),
1684                                         le16_to_cpu(fe->i_suballoc_bit));
1685 }
1686
1687 static inline void ocfs2_save_inode_ac_group(struct inode *dir,
1688                                              struct ocfs2_alloc_context *ac)
1689 {
1690         OCFS2_I(dir)->ip_last_used_group = ac->ac_last_group;
1691         OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
1692 }
1693
1694 int ocfs2_claim_new_inode(struct ocfs2_super *osb,
1695                           handle_t *handle,
1696                           struct inode *dir,
1697                           struct buffer_head *parent_fe_bh,
1698                           struct ocfs2_alloc_context *ac,
1699                           u16 *suballoc_bit,
1700                           u64 *fe_blkno)
1701 {
1702         int status;
1703         unsigned int num_bits;
1704         u64 bg_blkno;
1705
1706         mlog_entry_void();
1707
1708         BUG_ON(!ac);
1709         BUG_ON(ac->ac_bits_given != 0);
1710         BUG_ON(ac->ac_bits_wanted != 1);
1711         BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
1712
1713         ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
1714
1715         status = ocfs2_claim_suballoc_bits(osb,
1716                                            ac,
1717                                            handle,
1718                                            1,
1719                                            1,
1720                                            suballoc_bit,
1721                                            &num_bits,
1722                                            &bg_blkno);
1723         if (status < 0) {
1724                 mlog_errno(status);
1725                 goto bail;
1726         }
1727         atomic_inc(&osb->alloc_stats.bg_allocs);
1728
1729         BUG_ON(num_bits != 1);
1730
1731         *fe_blkno = bg_blkno + (u64) (*suballoc_bit);
1732         ac->ac_bits_given++;
1733         ocfs2_save_inode_ac_group(dir, ac);
1734         status = 0;
1735 bail:
1736         mlog_exit(status);
1737         return status;
1738 }
1739
1740 /* translate a group desc. blkno and it's bitmap offset into
1741  * disk cluster offset. */
1742 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
1743                                                    u64 bg_blkno,
1744                                                    u16 bg_bit_off)
1745 {
1746         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1747         u32 cluster = 0;
1748
1749         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1750
1751         if (bg_blkno != osb->first_cluster_group_blkno)
1752                 cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
1753         cluster += (u32) bg_bit_off;
1754         return cluster;
1755 }
1756
1757 /* given a cluster offset, calculate which block group it belongs to
1758  * and return that block offset. */
1759 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
1760 {
1761         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1762         u32 group_no;
1763
1764         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1765
1766         group_no = cluster / osb->bitmap_cpg;
1767         if (!group_no)
1768                 return osb->first_cluster_group_blkno;
1769         return ocfs2_clusters_to_blocks(inode->i_sb,
1770                                         group_no * osb->bitmap_cpg);
1771 }
1772
1773 /* given the block number of a cluster start, calculate which cluster
1774  * group and descriptor bitmap offset that corresponds to. */
1775 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
1776                                                 u64 data_blkno,
1777                                                 u64 *bg_blkno,
1778                                                 u16 *bg_bit_off)
1779 {
1780         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1781         u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
1782
1783         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1784
1785         *bg_blkno = ocfs2_which_cluster_group(inode,
1786                                               data_cluster);
1787
1788         if (*bg_blkno == osb->first_cluster_group_blkno)
1789                 *bg_bit_off = (u16) data_cluster;
1790         else
1791                 *bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
1792                                                              data_blkno - *bg_blkno);
1793 }
1794
1795 /*
1796  * min_bits - minimum contiguous chunk from this total allocation we
1797  * can handle. set to what we asked for originally for a full
1798  * contig. allocation, set to '1' to indicate we can deal with extents
1799  * of any size.
1800  */
1801 int __ocfs2_claim_clusters(struct ocfs2_super *osb,
1802                            handle_t *handle,
1803                            struct ocfs2_alloc_context *ac,
1804                            u32 min_clusters,
1805                            u32 max_clusters,
1806                            u32 *cluster_start,
1807                            u32 *num_clusters)
1808 {
1809         int status;
1810         unsigned int bits_wanted = max_clusters;
1811         u64 bg_blkno = 0;
1812         u16 bg_bit_off;
1813
1814         mlog_entry_void();
1815
1816         BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1817
1818         BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
1819                && ac->ac_which != OCFS2_AC_USE_MAIN);
1820
1821         if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
1822                 status = ocfs2_claim_local_alloc_bits(osb,
1823                                                       handle,
1824                                                       ac,
1825                                                       bits_wanted,
1826                                                       cluster_start,
1827                                                       num_clusters);
1828                 if (!status)
1829                         atomic_inc(&osb->alloc_stats.local_data);
1830         } else {
1831                 if (min_clusters > (osb->bitmap_cpg - 1)) {
1832                         /* The only paths asking for contiguousness
1833                          * should know about this already. */
1834                         mlog(ML_ERROR, "minimum allocation requested %u exceeds "
1835                              "group bitmap size %u!\n", min_clusters,
1836                              osb->bitmap_cpg);
1837                         status = -ENOSPC;
1838                         goto bail;
1839                 }
1840                 /* clamp the current request down to a realistic size. */
1841                 if (bits_wanted > (osb->bitmap_cpg - 1))
1842                         bits_wanted = osb->bitmap_cpg - 1;
1843
1844                 status = ocfs2_claim_suballoc_bits(osb,
1845                                                    ac,
1846                                                    handle,
1847                                                    bits_wanted,
1848                                                    min_clusters,
1849                                                    &bg_bit_off,
1850                                                    num_clusters,
1851                                                    &bg_blkno);
1852                 if (!status) {
1853                         *cluster_start =
1854                                 ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
1855                                                                  bg_blkno,
1856                                                                  bg_bit_off);
1857                         atomic_inc(&osb->alloc_stats.bitmap_data);
1858                 }
1859         }
1860         if (status < 0) {
1861                 if (status != -ENOSPC)
1862                         mlog_errno(status);
1863                 goto bail;
1864         }
1865
1866         ac->ac_bits_given += *num_clusters;
1867
1868 bail:
1869         mlog_exit(status);
1870         return status;
1871 }
1872
1873 int ocfs2_claim_clusters(struct ocfs2_super *osb,
1874                          handle_t *handle,
1875                          struct ocfs2_alloc_context *ac,
1876                          u32 min_clusters,
1877                          u32 *cluster_start,
1878                          u32 *num_clusters)
1879 {
1880         unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
1881
1882         return __ocfs2_claim_clusters(osb, handle, ac, min_clusters,
1883                                       bits_wanted, cluster_start, num_clusters);
1884 }
1885
1886 static inline int ocfs2_block_group_clear_bits(handle_t *handle,
1887                                                struct inode *alloc_inode,
1888                                                struct ocfs2_group_desc *bg,
1889                                                struct buffer_head *group_bh,
1890                                                unsigned int bit_off,
1891                                                unsigned int num_bits)
1892 {
1893         int status;
1894         unsigned int tmp;
1895         int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
1896         struct ocfs2_group_desc *undo_bg = NULL;
1897         int cluster_bitmap = 0;
1898
1899         mlog_entry_void();
1900
1901         /* The caller got this descriptor from
1902          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1903         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1904
1905         mlog(0, "off = %u, num = %u\n", bit_off, num_bits);
1906
1907         if (ocfs2_is_cluster_bitmap(alloc_inode))
1908                 journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
1909
1910         status = ocfs2_journal_access_gd(handle, alloc_inode, group_bh,
1911                                          journal_type);
1912         if (status < 0) {
1913                 mlog_errno(status);
1914                 goto bail;
1915         }
1916
1917         if (ocfs2_is_cluster_bitmap(alloc_inode))
1918                 cluster_bitmap = 1;
1919
1920         if (cluster_bitmap) {
1921                 jbd_lock_bh_state(group_bh);
1922                 undo_bg = (struct ocfs2_group_desc *)
1923                                         bh2jh(group_bh)->b_committed_data;
1924                 BUG_ON(!undo_bg);
1925         }
1926
1927         tmp = num_bits;
1928         while(tmp--) {
1929                 ocfs2_clear_bit((bit_off + tmp),
1930                                 (unsigned long *) bg->bg_bitmap);
1931                 if (cluster_bitmap)
1932                         ocfs2_set_bit(bit_off + tmp,
1933                                       (unsigned long *) undo_bg->bg_bitmap);
1934         }
1935         le16_add_cpu(&bg->bg_free_bits_count, num_bits);
1936
1937         if (cluster_bitmap)
1938                 jbd_unlock_bh_state(group_bh);
1939
1940         status = ocfs2_journal_dirty(handle, group_bh);
1941         if (status < 0)
1942                 mlog_errno(status);
1943 bail:
1944         return status;
1945 }
1946
1947 /*
1948  * expects the suballoc inode to already be locked.
1949  */
1950 int ocfs2_free_suballoc_bits(handle_t *handle,
1951                              struct inode *alloc_inode,
1952                              struct buffer_head *alloc_bh,
1953                              unsigned int start_bit,
1954                              u64 bg_blkno,
1955                              unsigned int count)
1956 {
1957         int status = 0;
1958         u32 tmp_used;
1959         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
1960         struct ocfs2_chain_list *cl = &fe->id2.i_chain;
1961         struct buffer_head *group_bh = NULL;
1962         struct ocfs2_group_desc *group;
1963
1964         mlog_entry_void();
1965
1966         /* The alloc_bh comes from ocfs2_free_dinode() or
1967          * ocfs2_free_clusters().  The callers have all locked the
1968          * allocator and gotten alloc_bh from the lock call.  This
1969          * validates the dinode buffer.  Any corruption that has happended
1970          * is a code bug. */
1971         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1972         BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
1973
1974         mlog(0, "%llu: freeing %u bits from group %llu, starting at %u\n",
1975              (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno, count,
1976              (unsigned long long)bg_blkno, start_bit);
1977
1978         status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
1979                                              &group_bh);
1980         if (status < 0) {
1981                 mlog_errno(status);
1982                 goto bail;
1983         }
1984         group = (struct ocfs2_group_desc *) group_bh->b_data;
1985
1986         BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
1987
1988         status = ocfs2_block_group_clear_bits(handle, alloc_inode,
1989                                               group, group_bh,
1990                                               start_bit, count);
1991         if (status < 0) {
1992                 mlog_errno(status);
1993                 goto bail;
1994         }
1995
1996         status = ocfs2_journal_access_di(handle, alloc_inode, alloc_bh,
1997                                          OCFS2_JOURNAL_ACCESS_WRITE);
1998         if (status < 0) {
1999                 mlog_errno(status);
2000                 goto bail;
2001         }
2002
2003         le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
2004                      count);
2005         tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
2006         fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
2007
2008         status = ocfs2_journal_dirty(handle, alloc_bh);
2009         if (status < 0) {
2010                 mlog_errno(status);
2011                 goto bail;
2012         }
2013
2014 bail:
2015         brelse(group_bh);
2016
2017         mlog_exit(status);
2018         return status;
2019 }
2020
2021 int ocfs2_free_dinode(handle_t *handle,
2022                       struct inode *inode_alloc_inode,
2023                       struct buffer_head *inode_alloc_bh,
2024                       struct ocfs2_dinode *di)
2025 {
2026         u64 blk = le64_to_cpu(di->i_blkno);
2027         u16 bit = le16_to_cpu(di->i_suballoc_bit);
2028         u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
2029
2030         return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
2031                                         inode_alloc_bh, bit, bg_blkno, 1);
2032 }
2033
2034 int ocfs2_free_clusters(handle_t *handle,
2035                        struct inode *bitmap_inode,
2036                        struct buffer_head *bitmap_bh,
2037                        u64 start_blk,
2038                        unsigned int num_clusters)
2039 {
2040         int status;
2041         u16 bg_start_bit;
2042         u64 bg_blkno;
2043         struct ocfs2_dinode *fe;
2044
2045         /* You can't ever have a contiguous set of clusters
2046          * bigger than a block group bitmap so we never have to worry
2047          * about looping on them. */
2048
2049         mlog_entry_void();
2050
2051         /* This is expensive. We can safely remove once this stuff has
2052          * gotten tested really well. */
2053         BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb, ocfs2_blocks_to_clusters(bitmap_inode->i_sb, start_blk)));
2054
2055         fe = (struct ocfs2_dinode *) bitmap_bh->b_data;
2056
2057         ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
2058                                      &bg_start_bit);
2059
2060         mlog(0, "want to free %u clusters starting at block %llu\n",
2061              num_clusters, (unsigned long long)start_blk);
2062         mlog(0, "bg_blkno = %llu, bg_start_bit = %u\n",
2063              (unsigned long long)bg_blkno, bg_start_bit);
2064
2065         status = ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
2066                                           bg_start_bit, bg_blkno,
2067                                           num_clusters);
2068         if (status < 0) {
2069                 mlog_errno(status);
2070                 goto out;
2071         }
2072
2073         ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
2074                                          num_clusters);
2075
2076 out:
2077         mlog_exit(status);
2078         return status;
2079 }
2080
2081 static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg)
2082 {
2083         printk("Block Group:\n");
2084         printk("bg_signature:       %s\n", bg->bg_signature);
2085         printk("bg_size:            %u\n", bg->bg_size);
2086         printk("bg_bits:            %u\n", bg->bg_bits);
2087         printk("bg_free_bits_count: %u\n", bg->bg_free_bits_count);
2088         printk("bg_chain:           %u\n", bg->bg_chain);
2089         printk("bg_generation:      %u\n", le32_to_cpu(bg->bg_generation));
2090         printk("bg_next_group:      %llu\n",
2091                (unsigned long long)bg->bg_next_group);
2092         printk("bg_parent_dinode:   %llu\n",
2093                (unsigned long long)bg->bg_parent_dinode);
2094         printk("bg_blkno:           %llu\n",
2095                (unsigned long long)bg->bg_blkno);
2096 }
2097
2098 static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe)
2099 {
2100         int i;
2101
2102         printk("Suballoc Inode %llu:\n", (unsigned long long)fe->i_blkno);
2103         printk("i_signature:                  %s\n", fe->i_signature);
2104         printk("i_size:                       %llu\n",
2105                (unsigned long long)fe->i_size);
2106         printk("i_clusters:                   %u\n", fe->i_clusters);
2107         printk("i_generation:                 %u\n",
2108                le32_to_cpu(fe->i_generation));
2109         printk("id1.bitmap1.i_used:           %u\n",
2110                le32_to_cpu(fe->id1.bitmap1.i_used));
2111         printk("id1.bitmap1.i_total:          %u\n",
2112                le32_to_cpu(fe->id1.bitmap1.i_total));
2113         printk("id2.i_chain.cl_cpg:           %u\n", fe->id2.i_chain.cl_cpg);
2114         printk("id2.i_chain.cl_bpc:           %u\n", fe->id2.i_chain.cl_bpc);
2115         printk("id2.i_chain.cl_count:         %u\n", fe->id2.i_chain.cl_count);
2116         printk("id2.i_chain.cl_next_free_rec: %u\n",
2117                fe->id2.i_chain.cl_next_free_rec);
2118         for(i = 0; i < fe->id2.i_chain.cl_next_free_rec; i++) {
2119                 printk("fe->id2.i_chain.cl_recs[%d].c_free:  %u\n", i,
2120                        fe->id2.i_chain.cl_recs[i].c_free);
2121                 printk("fe->id2.i_chain.cl_recs[%d].c_total: %u\n", i,
2122                        fe->id2.i_chain.cl_recs[i].c_total);
2123                 printk("fe->id2.i_chain.cl_recs[%d].c_blkno: %llu\n", i,
2124                        (unsigned long long)fe->id2.i_chain.cl_recs[i].c_blkno);
2125         }
2126 }
2127
2128 /*
2129  * For a given allocation, determine which allocators will need to be
2130  * accessed, and lock them, reserving the appropriate number of bits.
2131  *
2132  * Sparse file systems call this from ocfs2_write_begin_nolock()
2133  * and ocfs2_allocate_unwritten_extents().
2134  *
2135  * File systems which don't support holes call this from
2136  * ocfs2_extend_allocation().
2137  */
2138 int ocfs2_lock_allocators(struct inode *inode,
2139                           struct ocfs2_extent_tree *et,
2140                           u32 clusters_to_add, u32 extents_to_split,
2141                           struct ocfs2_alloc_context **data_ac,
2142                           struct ocfs2_alloc_context **meta_ac)
2143 {
2144         int ret = 0, num_free_extents;
2145         unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
2146         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2147
2148         *meta_ac = NULL;
2149         if (data_ac)
2150                 *data_ac = NULL;
2151
2152         BUG_ON(clusters_to_add != 0 && data_ac == NULL);
2153
2154         num_free_extents = ocfs2_num_free_extents(osb, inode, et);
2155         if (num_free_extents < 0) {
2156                 ret = num_free_extents;
2157                 mlog_errno(ret);
2158                 goto out;
2159         }
2160
2161         /*
2162          * Sparse allocation file systems need to be more conservative
2163          * with reserving room for expansion - the actual allocation
2164          * happens while we've got a journal handle open so re-taking
2165          * a cluster lock (because we ran out of room for another
2166          * extent) will violate ordering rules.
2167          *
2168          * Most of the time we'll only be seeing this 1 cluster at a time
2169          * anyway.
2170          *
2171          * Always lock for any unwritten extents - we might want to
2172          * add blocks during a split.
2173          */
2174         if (!num_free_extents ||
2175             (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
2176                 ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
2177                 if (ret < 0) {
2178                         if (ret != -ENOSPC)
2179                                 mlog_errno(ret);
2180                         goto out;
2181                 }
2182         }
2183
2184         if (clusters_to_add == 0)
2185                 goto out;
2186
2187         ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
2188         if (ret < 0) {
2189                 if (ret != -ENOSPC)
2190                         mlog_errno(ret);
2191                 goto out;
2192         }
2193
2194 out:
2195         if (ret) {
2196                 if (*meta_ac) {
2197                         ocfs2_free_alloc_context(*meta_ac);
2198                         *meta_ac = NULL;
2199                 }
2200
2201                 /*
2202                  * We cannot have an error and a non null *data_ac.
2203                  */
2204         }
2205
2206         return ret;
2207 }
2208
2209 /*
2210  * Read the inode specified by blkno to get suballoc_slot and
2211  * suballoc_bit.
2212  */
2213 static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno,
2214                                        u16 *suballoc_slot, u16 *suballoc_bit)
2215 {
2216         int status;
2217         struct buffer_head *inode_bh = NULL;
2218         struct ocfs2_dinode *inode_fe;
2219
2220         mlog_entry("blkno: %llu\n", (unsigned long long)blkno);
2221
2222         /* dirty read disk */
2223         status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh);
2224         if (status < 0) {
2225                 mlog(ML_ERROR, "read block %llu failed %d\n",
2226                      (unsigned long long)blkno, status);
2227                 goto bail;
2228         }
2229
2230         inode_fe = (struct ocfs2_dinode *) inode_bh->b_data;
2231         if (!OCFS2_IS_VALID_DINODE(inode_fe)) {
2232                 mlog(ML_ERROR, "invalid inode %llu requested\n",
2233                      (unsigned long long)blkno);
2234                 status = -EINVAL;
2235                 goto bail;
2236         }
2237
2238         if (le16_to_cpu(inode_fe->i_suballoc_slot) != (u16)OCFS2_INVALID_SLOT &&
2239             (u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) {
2240                 mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n",
2241                      (unsigned long long)blkno,
2242                      (u32)le16_to_cpu(inode_fe->i_suballoc_slot));
2243                 status = -EINVAL;
2244                 goto bail;
2245         }
2246
2247         if (suballoc_slot)
2248                 *suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot);
2249         if (suballoc_bit)
2250                 *suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit);
2251
2252 bail:
2253         brelse(inode_bh);
2254
2255         mlog_exit(status);
2256         return status;
2257 }
2258
2259 /*
2260  * test whether bit is SET in allocator bitmap or not.  on success, 0
2261  * is returned and *res is 1 for SET; 0 otherwise.  when fails, errno
2262  * is returned and *res is meaningless.  Call this after you have
2263  * cluster locked against suballoc, or you may get a result based on
2264  * non-up2date contents
2265  */
2266 static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb,
2267                                    struct inode *suballoc,
2268                                    struct buffer_head *alloc_bh, u64 blkno,
2269                                    u16 bit, int *res)
2270 {
2271         struct ocfs2_dinode *alloc_fe;
2272         struct ocfs2_group_desc *group;
2273         struct buffer_head *group_bh = NULL;
2274         u64 bg_blkno;
2275         int status;
2276
2277         mlog_entry("blkno: %llu bit: %u\n", (unsigned long long)blkno,
2278                    (unsigned int)bit);
2279
2280         alloc_fe = (struct ocfs2_dinode *)alloc_bh->b_data;
2281         if ((bit + 1) > ocfs2_bits_per_group(&alloc_fe->id2.i_chain)) {
2282                 mlog(ML_ERROR, "suballoc bit %u out of range of %u\n",
2283                      (unsigned int)bit,
2284                      ocfs2_bits_per_group(&alloc_fe->id2.i_chain));
2285                 status = -EINVAL;
2286                 goto bail;
2287         }
2288
2289         bg_blkno = ocfs2_which_suballoc_group(blkno, bit);
2290         status = ocfs2_read_group_descriptor(suballoc, alloc_fe, bg_blkno,
2291                                              &group_bh);
2292         if (status < 0) {
2293                 mlog(ML_ERROR, "read group %llu failed %d\n",
2294                      (unsigned long long)bg_blkno, status);
2295                 goto bail;
2296         }
2297
2298         group = (struct ocfs2_group_desc *) group_bh->b_data;
2299         *res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap);
2300
2301 bail:
2302         brelse(group_bh);
2303
2304         mlog_exit(status);
2305         return status;
2306 }
2307
2308 /*
2309  * Test if the bit representing this inode (blkno) is set in the
2310  * suballocator.
2311  *
2312  * On success, 0 is returned and *res is 1 for SET; 0 otherwise.
2313  *
2314  * In the event of failure, a negative value is returned and *res is
2315  * meaningless.
2316  *
2317  * Callers must make sure to hold nfs_sync_lock to prevent
2318  * ocfs2_delete_inode() on another node from accessing the same
2319  * suballocator concurrently.
2320  */
2321 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res)
2322 {
2323         int status;
2324         u16 suballoc_bit = 0, suballoc_slot = 0;
2325         struct inode *inode_alloc_inode;
2326         struct buffer_head *alloc_bh = NULL;
2327
2328         mlog_entry("blkno: %llu", (unsigned long long)blkno);
2329
2330         status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot,
2331                                              &suballoc_bit);
2332         if (status < 0) {
2333                 mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status);
2334                 goto bail;
2335         }
2336
2337         inode_alloc_inode =
2338                 ocfs2_get_system_file_inode(osb, INODE_ALLOC_SYSTEM_INODE,
2339                                             suballoc_slot);
2340         if (!inode_alloc_inode) {
2341                 /* the error code could be inaccurate, but we are not able to
2342                  * get the correct one. */
2343                 status = -EINVAL;
2344                 mlog(ML_ERROR, "unable to get alloc inode in slot %u\n",
2345                      (u32)suballoc_slot);
2346                 goto bail;
2347         }
2348
2349         mutex_lock(&inode_alloc_inode->i_mutex);
2350         status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0);
2351         if (status < 0) {
2352                 mutex_unlock(&inode_alloc_inode->i_mutex);
2353                 mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n",
2354                      (u32)suballoc_slot, status);
2355                 goto bail;
2356         }
2357
2358         status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh,
2359                                          blkno, suballoc_bit, res);
2360         if (status < 0)
2361                 mlog(ML_ERROR, "test suballoc bit failed %d\n", status);
2362
2363         ocfs2_inode_unlock(inode_alloc_inode, 0);
2364         mutex_unlock(&inode_alloc_inode->i_mutex);
2365
2366         iput(inode_alloc_inode);
2367         brelse(alloc_bh);
2368 bail:
2369         mlog_exit(status);
2370         return status;
2371 }