arch/all-pc/boot/grub2-aros/grub-core/fs/nilfs2.c

   1 /*
   2  *  nilfs2.c - New Implementation of Log filesystem
   3  *
   4  *  Written by Jiro SEKIBA <jir@unicus.jp>
   5  *
   6  *  Copyright (C) 2003,2004,2005,2007,2008,2010  Free Software Foundation, Inc.
   7  *
   8  *  GRUB is free software: you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation, either version 3 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  GRUB is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22
  23 /* Filetype information as used in inodes.  */
  24 #define FILETYPE_INO_MASK       0170000
  25 #define FILETYPE_INO_REG        0100000
  26 #define FILETYPE_INO_DIRECTORY  0040000
  27 #define FILETYPE_INO_SYMLINK    0120000
  28
  29 #include <grub/err.h>
  30 #include <grub/file.h>
  31 #include <grub/mm.h>
  32 #include <grub/misc.h>
  33 #include <grub/disk.h>
  34 #include <grub/dl.h>
  35 #include <grub/types.h>
  36 #include <grub/fshelp.h>
  37
  38 GRUB_MOD_LICENSE ("GPLv3+");
  39
  40 #define NILFS_INODE_BMAP_SIZE   7
  41
  42 #define NILFS_SUPORT_REV        2
  43
  44 /* Magic value used to identify an nilfs2 filesystem.  */
  45 #define NILFS2_SUPER_MAGIC      0x3434
  46 /* nilfs btree node flag.  */
  47 #define NILFS_BTREE_NODE_ROOT   0x01
  48
  49 /* nilfs btree node level. */
  50 #define NILFS_BTREE_LEVEL_DATA          0
  51 #define NILFS_BTREE_LEVEL_NODE_MIN      (NILFS_BTREE_LEVEL_DATA + 1)
  52
  53 /* nilfs 1st super block posission from beginning of the partition
  54    in 512 block size */
  55 #define NILFS_1ST_SUPER_BLOCK   2
  56 /* nilfs 2nd super block posission from beginning of the partition
  57    in 512 block size */
  58 #define NILFS_2ND_SUPER_BLOCK(devsize)  (((devsize >> 3) - 1) << 3)
  59
  60 #define LOG_INODE_SIZE 7
  61 struct grub_nilfs2_inode
  62 {
  63   grub_uint64_t i_blocks;
  64   grub_uint64_t i_size;
  65   grub_uint64_t i_ctime;
  66   grub_uint64_t i_mtime;
  67   grub_uint32_t i_ctime_nsec;
  68   grub_uint32_t i_mtime_nsec;
  69   grub_uint32_t i_uid;
  70   grub_uint32_t i_gid;
  71   grub_uint16_t i_mode;
  72   grub_uint16_t i_links_count;
  73   grub_uint32_t i_flags;
  74   grub_uint64_t i_bmap[NILFS_INODE_BMAP_SIZE];
  75 #define i_device_code   i_bmap[0]
  76   grub_uint64_t i_xattr;
  77   grub_uint32_t i_generation;
  78   grub_uint32_t i_pad;
  79 };
  80
  81 struct grub_nilfs2_super_root
  82 {
  83   grub_uint32_t sr_sum;
  84   grub_uint16_t sr_bytes;
  85   grub_uint16_t sr_flags;
  86   grub_uint64_t sr_nongc_ctime;
  87   struct grub_nilfs2_inode sr_dat;
  88   struct grub_nilfs2_inode sr_cpfile;
  89   struct grub_nilfs2_inode sr_sufile;
  90 };
  91
  92 struct grub_nilfs2_super_block
  93 {
  94   grub_uint32_t s_rev_level;
  95   grub_uint16_t s_minor_rev_level;
  96   grub_uint16_t s_magic;
  97   grub_uint16_t s_bytes;
  98   grub_uint16_t s_flags;
  99   grub_uint32_t s_crc_seed;
 100   grub_uint32_t s_sum;
 101   grub_uint32_t s_log_block_size;
 102   grub_uint64_t s_nsegments;
 103   grub_uint64_t s_dev_size;
 104   grub_uint64_t s_first_data_block;
 105   grub_uint32_t s_blocks_per_segment;
 106   grub_uint32_t s_r_segments_percentage;
 107   grub_uint64_t s_last_cno;
 108   grub_uint64_t s_last_pseg;
 109   grub_uint64_t s_last_seq;
 110   grub_uint64_t s_free_blocks_count;
 111   grub_uint64_t s_ctime;
 112   grub_uint64_t s_mtime;
 113   grub_uint64_t s_wtime;
 114   grub_uint16_t s_mnt_count;
 115   grub_uint16_t s_max_mnt_count;
 116   grub_uint16_t s_state;
 117   grub_uint16_t s_errors;
 118   grub_uint64_t s_lastcheck;
 119   grub_uint32_t s_checkinterval;
 120   grub_uint32_t s_creator_os;
 121   grub_uint16_t s_def_resuid;
 122   grub_uint16_t s_def_resgid;
 123   grub_uint32_t s_first_ino;
 124   grub_uint16_t s_inode_size;
 125   grub_uint16_t s_dat_entry_size;
 126   grub_uint16_t s_checkpoint_size;
 127   grub_uint16_t s_segment_usage_size;
 128   grub_uint8_t s_uuid[16];
 129   char s_volume_name[80];
 130   grub_uint32_t s_c_interval;
 131   grub_uint32_t s_c_block_max;
 132   grub_uint32_t s_reserved[192];
 133 };
 134
 135 struct grub_nilfs2_dir_entry
 136 {
 137   grub_uint64_t inode;
 138   grub_uint16_t rec_len;
 139 #define MAX_NAMELEN 255
 140   grub_uint8_t name_len;
 141   grub_uint8_t file_type;
 142 #if 0                           /* followed by file name. */
 143   char name[NILFS_NAME_LEN];
 144   char pad;
 145 #endif
 146 } GRUB_PACKED;
 147
 148 enum
 149 {
 150   NILFS_FT_UNKNOWN,
 151   NILFS_FT_REG_FILE,
 152   NILFS_FT_DIR,
 153   NILFS_FT_CHRDEV,
 154   NILFS_FT_BLKDEV,
 155   NILFS_FT_FIFO,
 156   NILFS_FT_SOCK,
 157   NILFS_FT_SYMLINK,
 158   NILFS_FT_MAX
 159 };
 160
 161 struct grub_nilfs2_finfo
 162 {
 163   grub_uint64_t fi_ino;
 164   grub_uint64_t fi_cno;
 165   grub_uint32_t fi_nblocks;
 166   grub_uint32_t fi_ndatablk;
 167 };
 168
 169 struct grub_nilfs2_binfo_v
 170 {
 171   grub_uint64_t bi_vblocknr;
 172   grub_uint64_t bi_blkoff;
 173 };
 174
 175 struct grub_nilfs2_binfo_dat
 176 {
 177   grub_uint64_t bi_blkoff;
 178   grub_uint8_t bi_level;
 179   grub_uint8_t bi_pad[7];
 180 };
 181
 182 union grub_nilfs2_binfo
 183 {
 184   struct grub_nilfs2_binfo_v bi_v;
 185   struct grub_nilfs2_binfo_dat bi_dat;
 186 };
 187
 188 struct grub_nilfs2_segment_summary
 189 {
 190   grub_uint32_t ss_datasum;
 191   grub_uint32_t ss_sumsum;
 192   grub_uint32_t ss_magic;
 193   grub_uint16_t ss_bytes;
 194   grub_uint16_t ss_flags;
 195   grub_uint64_t ss_seq;
 196   grub_uint64_t ss_create;
 197   grub_uint64_t ss_next;
 198   grub_uint32_t ss_nblocks;
 199   grub_uint32_t ss_nfinfo;
 200   grub_uint32_t ss_sumbytes;
 201   grub_uint32_t ss_pad;
 202 };
 203
 204 struct grub_nilfs2_btree_node
 205 {
 206   grub_uint8_t bn_flags;
 207   grub_uint8_t bn_level;
 208   grub_uint16_t bn_nchildren;
 209   grub_uint32_t bn_pad;
 210   grub_uint64_t keys[0];
 211 };
 212
 213 struct grub_nilfs2_palloc_group_desc
 214 {
 215   grub_uint32_t pg_nfrees;
 216 };
 217
 218 #define LOG_SIZE_GROUP_DESC 2
 219
 220 #define LOG_NILFS_DAT_ENTRY_SIZE 5
 221 struct grub_nilfs2_dat_entry
 222 {
 223   grub_uint64_t de_blocknr;
 224   grub_uint64_t de_start;
 225   grub_uint64_t de_end;
 226   grub_uint64_t de_rsv;
 227 };
 228
 229 struct grub_nilfs2_snapshot_list
 230 {
 231   grub_uint64_t ssl_next;
 232   grub_uint64_t ssl_prev;
 233 };
 234
 235 struct grub_nilfs2_cpfile_header
 236 {
 237   grub_uint64_t ch_ncheckpoints;
 238   grub_uint64_t ch_nsnapshots;
 239   struct grub_nilfs2_snapshot_list ch_snapshot_list;
 240 };
 241
 242 struct grub_nilfs2_checkpoint
 243 {
 244   grub_uint32_t cp_flags;
 245   grub_uint32_t cp_checkpoints_count;
 246   struct grub_nilfs2_snapshot_list cp_snapshot_list;
 247   grub_uint64_t cp_cno;
 248   grub_uint64_t cp_create;
 249   grub_uint64_t cp_nblk_inc;
 250   grub_uint64_t cp_inodes_count;
 251   grub_uint64_t cp_blocks_count;
 252   struct grub_nilfs2_inode cp_ifile_inode;
 253 };
 254
 255
 256 #define NILFS_BMAP_LARGE        0x1
 257 #define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(grub_uint64_t))
 258
 259 /* nilfs extra padding for nonroot btree node. */
 260 #define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(grub_uint64_t))
 261 #define NILFS_BTREE_ROOT_SIZE   NILFS_BMAP_SIZE
 262 #define NILFS_BTREE_ROOT_NCHILDREN_MAX \
 263  ((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) / \
 264   (sizeof(grub_uint64_t) + sizeof(grub_uint64_t)) )
 265
 266
 267 struct grub_fshelp_node
 268 {
 269   struct grub_nilfs2_data *data;
 270   struct grub_nilfs2_inode inode;
 271   grub_uint64_t ino;
 272   int inode_read;
 273 };
 274
 275 struct grub_nilfs2_data
 276 {
 277   struct grub_nilfs2_super_block sblock;
 278   struct grub_nilfs2_super_root sroot;
 279   struct grub_nilfs2_inode ifile;
 280   grub_disk_t disk;
 281   struct grub_nilfs2_inode *inode;
 282   struct grub_fshelp_node diropen;
 283 };
 284
 285 /* Log2 size of nilfs2 block in 512 blocks.  */
 286 #define LOG2_NILFS2_BLOCK_SIZE(data)                    \
 287         (grub_le_to_cpu32 (data->sblock.s_log_block_size) + 1)
 288
 289 /* Log2 size of nilfs2 block in bytes.  */
 290 #define LOG2_BLOCK_SIZE(data)                                   \
 291         (grub_le_to_cpu32 (data->sblock.s_log_block_size) + 10)
 292
 293 /* The size of an nilfs2 block in bytes.  */
 294 #define NILFS2_BLOCK_SIZE(data)         (1 << LOG2_BLOCK_SIZE (data))
 295
 296 static grub_uint64_t
 297 grub_nilfs2_dat_translate (struct grub_nilfs2_data *data, grub_uint64_t key);
 298 static grub_dl_t my_mod;
 299 \f
 300
 301
 302 static inline unsigned long
 303 grub_nilfs2_log_palloc_entries_per_group (struct grub_nilfs2_data *data)
 304 {
 305   return LOG2_BLOCK_SIZE (data) + 3;
 306 }
 307
 308 static inline grub_uint64_t
 309 grub_nilfs2_palloc_group (struct grub_nilfs2_data *data,
 310                           grub_uint64_t nr, grub_uint64_t * offset)
 311 {
 312   *offset = nr & ((1 << grub_nilfs2_log_palloc_entries_per_group (data)) - 1);
 313   return nr >> grub_nilfs2_log_palloc_entries_per_group (data);
 314 }
 315
 316 static inline grub_uint32_t
 317 grub_nilfs2_palloc_log_groups_per_desc_block (struct grub_nilfs2_data *data)
 318 {
 319   return LOG2_BLOCK_SIZE (data) - LOG_SIZE_GROUP_DESC;
 320
 321   COMPILE_TIME_ASSERT (sizeof (struct grub_nilfs2_palloc_group_desc)
 322                        == (1 << LOG_SIZE_GROUP_DESC));
 323 }
 324
 325 static inline grub_uint32_t
 326 grub_nilfs2_log_entries_per_block_log (struct grub_nilfs2_data *data,
 327                                        unsigned long log_entry_size)
 328 {
 329   return LOG2_BLOCK_SIZE (data) - log_entry_size;
 330 }
 331
 332
 333 static inline grub_uint32_t
 334 grub_nilfs2_blocks_per_group_log (struct grub_nilfs2_data *data,
 335                                   unsigned long log_entry_size)
 336 {
 337   return (1 << (grub_nilfs2_log_palloc_entries_per_group (data)
 338                 - grub_nilfs2_log_entries_per_block_log (data,
 339                                                          log_entry_size))) + 1;
 340 }
 341
 342 static inline grub_uint32_t
 343 grub_nilfs2_blocks_per_desc_block_log (struct grub_nilfs2_data *data,
 344                                        unsigned long log_entry_size)
 345 {
 346   return(grub_nilfs2_blocks_per_group_log (data, log_entry_size)
 347          << grub_nilfs2_palloc_log_groups_per_desc_block (data)) + 1;
 348 }
 349
 350 static inline grub_uint32_t
 351 grub_nilfs2_palloc_desc_block_offset_log (struct grub_nilfs2_data *data,
 352                                           unsigned long group,
 353                                           unsigned long log_entry_size)
 354 {
 355   grub_uint32_t desc_block =
 356     group >> grub_nilfs2_palloc_log_groups_per_desc_block (data);
 357   return desc_block * grub_nilfs2_blocks_per_desc_block_log (data,
 358                                                              log_entry_size);
 359 }
 360
 361 static inline grub_uint32_t
 362 grub_nilfs2_palloc_bitmap_block_offset (struct grub_nilfs2_data *data,
 363                                         unsigned long group,
 364                                         unsigned long log_entry_size)
 365 {
 366   unsigned long desc_offset = group
 367     & ((1 << grub_nilfs2_palloc_log_groups_per_desc_block (data)) - 1);
 368
 369   return grub_nilfs2_palloc_desc_block_offset_log (data, group, log_entry_size)
 370     + 1
 371     + desc_offset * grub_nilfs2_blocks_per_group_log (data, log_entry_size);
 372 }
 373
 374 static inline grub_uint32_t
 375 grub_nilfs2_palloc_entry_offset_log (struct grub_nilfs2_data *data,
 376                                      grub_uint64_t nr,
 377                                      unsigned long log_entry_size)
 378 {
 379   unsigned long group;
 380   grub_uint64_t group_offset;
 381
 382   group = grub_nilfs2_palloc_group (data, nr, &group_offset);
 383
 384   return grub_nilfs2_palloc_bitmap_block_offset (data, group,
 385                                                  log_entry_size) + 1 +
 386     (group_offset >> grub_nilfs2_log_entries_per_block_log (data,
 387                                                             log_entry_size));
 388
 389 }
 390
 391 static inline struct grub_nilfs2_btree_node *
 392 grub_nilfs2_btree_get_root (struct grub_nilfs2_inode *inode)
 393 {
 394   return (struct grub_nilfs2_btree_node *) &inode->i_bmap[0];
 395 }
 396
 397 static inline int
 398 grub_nilfs2_btree_get_level (struct grub_nilfs2_btree_node *node)
 399 {
 400   return node->bn_level;
 401 }
 402
 403 static inline grub_uint64_t *
 404 grub_nilfs2_btree_node_dkeys (struct grub_nilfs2_btree_node *node)
 405 {
 406   return (node->keys +
 407           ((node->bn_flags & NILFS_BTREE_NODE_ROOT) ?
 408            0 : (NILFS_BTREE_NODE_EXTRA_PAD_SIZE / sizeof (grub_uint64_t))));
 409 }
 410
 411 static inline grub_uint64_t
 412 grub_nilfs2_btree_node_get_key (struct grub_nilfs2_btree_node *node,
 413                                 int index)
 414 {
 415   return grub_le_to_cpu64 (*(grub_nilfs2_btree_node_dkeys (node) + index));
 416 }
 417
 418 static inline int
 419 grub_nilfs2_btree_node_lookup (struct grub_nilfs2_btree_node *node,
 420                                grub_uint64_t key, int *indexp)
 421 {
 422   grub_uint64_t nkey;
 423   int index, low, high, s;
 424
 425   low = 0;
 426   high = grub_le_to_cpu16 (node->bn_nchildren) - 1;
 427   index = 0;
 428   s = 0;
 429   while (low <= high)
 430     {
 431       index = (low + high) / 2;
 432       nkey = grub_nilfs2_btree_node_get_key (node, index);
 433       if (nkey == key)
 434         {
 435           *indexp = index;
 436           return 1;
 437         }
 438       else if (nkey < key)
 439         {
 440           low = index + 1;
 441           s = -1;
 442         }
 443       else
 444         {
 445           high = index - 1;
 446           s = 1;
 447         }
 448     }
 449
 450   if (node->bn_level > NILFS_BTREE_LEVEL_NODE_MIN)
 451     {
 452       if (s > 0 && index > 0)
 453         index--;
 454     }
 455   else if (s < 0)
 456     index++;
 457
 458   *indexp = index;
 459   return s == 0;
 460 }
 461
 462 static inline int
 463 grub_nilfs2_btree_node_nchildren_max (struct grub_nilfs2_data *data,
 464                                       struct grub_nilfs2_btree_node *node)
 465 {
 466   int node_children_max = ((NILFS2_BLOCK_SIZE (data) -
 467                             sizeof (struct grub_nilfs2_btree_node) -
 468                             NILFS_BTREE_NODE_EXTRA_PAD_SIZE) /
 469                            (sizeof (grub_uint64_t) + sizeof (grub_uint64_t)));
 470
 471   return (node->bn_flags & NILFS_BTREE_NODE_ROOT) ? 3 : node_children_max;
 472 }
 473
 474 static inline grub_uint64_t *
 475 grub_nilfs2_btree_node_dptrs (struct grub_nilfs2_data *data,
 476                               struct grub_nilfs2_btree_node *node)
 477 {
 478   return (grub_uint64_t *) (grub_nilfs2_btree_node_dkeys (node) +
 479                             grub_nilfs2_btree_node_nchildren_max (data,
 480                                                                   node));
 481 }
 482
 483 static inline grub_uint64_t
 484 grub_nilfs2_btree_node_get_ptr (struct grub_nilfs2_data *data,
 485                                 struct grub_nilfs2_btree_node *node,
 486                                 int index)
 487 {
 488   return
 489     grub_le_to_cpu64 (*(grub_nilfs2_btree_node_dptrs (data, node) + index));
 490 }
 491
 492 static inline int
 493 grub_nilfs2_btree_get_nonroot_node (struct grub_nilfs2_data *data,
 494                                     grub_uint64_t ptr, void *block)
 495 {
 496   grub_disk_t disk = data->disk;
 497   unsigned int nilfs2_block_count = (1 << LOG2_NILFS2_BLOCK_SIZE (data));
 498
 499   return grub_disk_read (disk, ptr * nilfs2_block_count, 0,
 500                          NILFS2_BLOCK_SIZE (data), block);
 501 }
 502
 503 static grub_uint64_t
 504 grub_nilfs2_btree_lookup (struct grub_nilfs2_data *data,
 505                           struct grub_nilfs2_inode *inode,
 506                           grub_uint64_t key, int need_translate)
 507 {
 508   struct grub_nilfs2_btree_node *node;
 509   void *block;
 510   grub_uint64_t ptr;
 511   int level, found = 0, index;
 512
 513   block = grub_malloc (NILFS2_BLOCK_SIZE (data));
 514   if (!block)
 515     return -1;
 516
 517   node = grub_nilfs2_btree_get_root (inode);
 518   level = grub_nilfs2_btree_get_level (node);
 519
 520   found = grub_nilfs2_btree_node_lookup (node, key, &index);
 521   ptr = grub_nilfs2_btree_node_get_ptr (data, node, index);
 522   if (need_translate)
 523     ptr = grub_nilfs2_dat_translate (data, ptr);
 524
 525   for (level--; level >= NILFS_BTREE_LEVEL_NODE_MIN; level--)
 526     {
 527       grub_nilfs2_btree_get_nonroot_node (data, ptr, block);
 528       if (grub_errno)
 529         {
 530           goto fail;
 531         }
 532       node = (struct grub_nilfs2_btree_node *) block;
 533
 534       if (node->bn_level != level)
 535         {
 536           grub_error (GRUB_ERR_BAD_FS, "btree level mismatch\n");
 537           goto fail;
 538         }
 539
 540       if (!found)
 541         found = grub_nilfs2_btree_node_lookup (node, key, &index);
 542       else
 543         index = 0;
 544
 545       if (index < grub_nilfs2_btree_node_nchildren_max (data, node))
 546         {
 547           ptr = grub_nilfs2_btree_node_get_ptr (data, node, index);
 548           if (need_translate)
 549             ptr = grub_nilfs2_dat_translate (data, ptr);
 550         }
 551       else
 552         {
 553           grub_error (GRUB_ERR_BAD_FS, "btree corruption\n");
 554           goto fail;
 555         }
 556     }
 557
 558   grub_free (block);
 559
 560   if (!found)
 561     return -1;
 562
 563   return ptr;
 564  fail:
 565   grub_free (block);
 566   return -1;
 567 }
 568
 569 static inline grub_uint64_t
 570 grub_nilfs2_direct_lookup (struct grub_nilfs2_inode *inode, grub_uint64_t key)
 571 {
 572   return grub_le_to_cpu64 (inode->i_bmap[1 + key]);
 573 }
 574
 575 static inline grub_uint64_t
 576 grub_nilfs2_bmap_lookup (struct grub_nilfs2_data *data,
 577                          struct grub_nilfs2_inode *inode,
 578                          grub_uint64_t key, int need_translate)
 579 {
 580   struct grub_nilfs2_btree_node *root = grub_nilfs2_btree_get_root (inode);
 581   if (root->bn_flags & NILFS_BMAP_LARGE)
 582     return grub_nilfs2_btree_lookup (data, inode, key, need_translate);
 583   else
 584     {
 585       grub_uint64_t ptr;
 586       ptr = grub_nilfs2_direct_lookup (inode, key);
 587       if (need_translate)
 588         ptr = grub_nilfs2_dat_translate (data, ptr);
 589       return ptr;
 590     }
 591 }
 592
 593 static grub_uint64_t
 594 grub_nilfs2_dat_translate (struct grub_nilfs2_data *data, grub_uint64_t key)
 595 {
 596   struct grub_nilfs2_dat_entry entry;
 597   grub_disk_t disk = data->disk;
 598   grub_uint64_t pptr;
 599   grub_uint64_t blockno, offset;
 600   unsigned int nilfs2_block_count = (1 << LOG2_NILFS2_BLOCK_SIZE (data));
 601
 602   blockno = grub_nilfs2_palloc_entry_offset_log (data, key,
 603                                                  LOG_NILFS_DAT_ENTRY_SIZE);
 604
 605   offset = ((key * sizeof (struct grub_nilfs2_dat_entry))
 606             & ((1 << LOG2_BLOCK_SIZE (data)) - 1));
 607
 608   pptr = grub_nilfs2_bmap_lookup (data, &data->sroot.sr_dat, blockno, 0);
 609   if (pptr == (grub_uint64_t) - 1)
 610     {
 611       grub_error (GRUB_ERR_BAD_FS, "btree lookup failure");
 612       return -1;
 613     }
 614
 615   grub_disk_read (disk, pptr * nilfs2_block_count, offset,
 616                   sizeof (struct grub_nilfs2_dat_entry), &entry);
 617
 618   return grub_le_to_cpu64 (entry.de_blocknr);
 619 }
 620
 621
 622 static grub_disk_addr_t
 623 grub_nilfs2_read_block (grub_fshelp_node_t node, grub_disk_addr_t fileblock)
 624 {
 625   struct grub_nilfs2_data *data = node->data;
 626   struct grub_nilfs2_inode *inode = &node->inode;
 627   grub_uint64_t pptr = -1;
 628
 629   pptr = grub_nilfs2_bmap_lookup (data, inode, fileblock, 1);
 630   if (pptr == (grub_uint64_t) - 1)
 631     {
 632       grub_error (GRUB_ERR_BAD_FS, "btree lookup failure");
 633       return -1;
 634     }
 635
 636   return pptr;
 637 }
 638
 639 /* Read LEN bytes from the file described by DATA starting with byte
 640    POS.  Return the amount of read bytes in READ.  */
 641 static grub_ssize_t
 642 grub_nilfs2_read_file (grub_fshelp_node_t node,
 643                        grub_disk_read_hook_t read_hook, void *read_hook_data,
 644                        grub_off_t pos, grub_size_t len, char *buf)
 645 {
 646   return grub_fshelp_read_file (node->data->disk, node,
 647                                 read_hook, read_hook_data,
 648                                 pos, len, buf, grub_nilfs2_read_block,
 649                                 grub_le_to_cpu64 (node->inode.i_size),
 650                                 LOG2_NILFS2_BLOCK_SIZE (node->data), 0);
 651
 652 }
 653
 654 static grub_err_t
 655 grub_nilfs2_read_checkpoint (struct grub_nilfs2_data *data,
 656                              grub_uint64_t cpno,
 657                              struct grub_nilfs2_checkpoint *cpp)
 658 {
 659   grub_uint64_t blockno;
 660   grub_uint64_t offset;
 661   grub_uint64_t pptr;
 662   grub_disk_t disk = data->disk;
 663   unsigned int nilfs2_block_count = (1 << LOG2_NILFS2_BLOCK_SIZE (data));
 664
 665   /* Assume sizeof(struct grub_nilfs2_cpfile_header) <
 666      sizeof(struct grub_nilfs2_checkpoint).
 667    */
 668   blockno = grub_divmod64 (cpno, NILFS2_BLOCK_SIZE (data) /
 669                           sizeof (struct grub_nilfs2_checkpoint), &offset);
 670
 671   pptr = grub_nilfs2_bmap_lookup (data, &data->sroot.sr_cpfile, blockno, 1);
 672   if (pptr == (grub_uint64_t) - 1)
 673     {
 674       return grub_error (GRUB_ERR_BAD_FS, "btree lookup failure");
 675     }
 676
 677   return grub_disk_read (disk, pptr * nilfs2_block_count,
 678                          offset * sizeof (struct grub_nilfs2_checkpoint),
 679                          sizeof (struct grub_nilfs2_checkpoint), cpp);
 680 }
 681
 682 static inline grub_err_t
 683 grub_nilfs2_read_last_checkpoint (struct grub_nilfs2_data *data,
 684                                   struct grub_nilfs2_checkpoint *cpp)
 685 {
 686   return grub_nilfs2_read_checkpoint (data,
 687                                       grub_le_to_cpu64 (data->
 688                                                         sblock.s_last_cno),
 689                                       cpp);
 690 }
 691
 692 /* Read the inode INO for the file described by DATA into INODE.  */
 693 static grub_err_t
 694 grub_nilfs2_read_inode (struct grub_nilfs2_data *data,
 695                         grub_uint64_t ino, struct grub_nilfs2_inode *inodep)
 696 {
 697   grub_uint64_t blockno;
 698   grub_uint64_t offset;
 699   grub_uint64_t pptr;
 700   grub_disk_t disk = data->disk;
 701   unsigned int nilfs2_block_count = (1 << LOG2_NILFS2_BLOCK_SIZE (data));
 702
 703   blockno = grub_nilfs2_palloc_entry_offset_log (data, ino,
 704                                                  LOG_INODE_SIZE);
 705
 706   offset = ((sizeof (struct grub_nilfs2_inode) * ino)
 707             & ((1 << LOG2_BLOCK_SIZE (data)) - 1));
 708   pptr = grub_nilfs2_bmap_lookup (data, &data->ifile, blockno, 1);
 709   if (pptr == (grub_uint64_t) - 1)
 710     {
 711       return grub_error (GRUB_ERR_BAD_FS, "btree lookup failure");
 712     }
 713
 714   return grub_disk_read (disk, pptr * nilfs2_block_count, offset,
 715                          sizeof (struct grub_nilfs2_inode), inodep);
 716 }
 717
 718 static int
 719 grub_nilfs2_valid_sb (struct grub_nilfs2_super_block *sbp)
 720 {
 721   if (grub_le_to_cpu16 (sbp->s_magic) != NILFS2_SUPER_MAGIC)
 722     return 0;
 723
 724   if (grub_le_to_cpu32 (sbp->s_rev_level) != NILFS_SUPORT_REV)
 725     return 0;
 726
 727   /* 20 already means 1GiB blocks. We don't want to deal with blocks overflowing int32. */
 728   if (grub_le_to_cpu32 (sbp->s_log_block_size) > 20)
 729     return 0;
 730
 731   return 1;
 732 }
 733
 734 static grub_err_t
 735 grub_nilfs2_load_sb (struct grub_nilfs2_data *data)
 736 {
 737   grub_disk_t disk = data->disk;
 738   struct grub_nilfs2_super_block sb2;
 739   grub_uint64_t partition_size;
 740   int valid[2];
 741   int swp = 0;
 742   grub_err_t err;
 743
 744   /* Read first super block. */
 745   err = grub_disk_read (disk, NILFS_1ST_SUPER_BLOCK, 0,
 746                         sizeof (struct grub_nilfs2_super_block), &data->sblock);
 747   if (err)
 748     return err;
 749   /* Make sure if 1st super block is valid.  */
 750   valid[0] = grub_nilfs2_valid_sb (&data->sblock);
 751
 752   if (valid[0])
 753     partition_size = (grub_le_to_cpu64 (data->sblock.s_dev_size)
 754                       >> GRUB_DISK_SECTOR_BITS);
 755   else
 756     partition_size = grub_disk_get_size (disk);
 757   if (partition_size != GRUB_DISK_SIZE_UNKNOWN)
 758     {
 759       /* Read second super block. */
 760       err = grub_disk_read (disk, NILFS_2ND_SUPER_BLOCK (partition_size), 0,
 761                             sizeof (struct grub_nilfs2_super_block), &sb2);
 762       if (err)
 763         {
 764           valid[1] = 0;
 765           grub_errno = GRUB_ERR_NONE;
 766         }
 767       else
 768         /* Make sure if 2nd super block is valid.  */
 769         valid[1] = grub_nilfs2_valid_sb (&sb2);
 770     }
 771   else
 772     /* 2nd super block may not exist, so it's invalid. */
 773     valid[1] = 0;
 774
 775   if (!valid[0] && !valid[1])
 776     return grub_error (GRUB_ERR_BAD_FS, "not a nilfs2 filesystem");
 777
 778   swp = valid[1] && (!valid[0] ||
 779                      grub_le_to_cpu64 (data->sblock.s_last_cno) <
 780                      grub_le_to_cpu64 (sb2.s_last_cno));
 781
 782   /* swap if first super block is invalid or older than second one. */
 783   if (swp)
 784     grub_memcpy (&data->sblock, &sb2,
 785                  sizeof (struct grub_nilfs2_super_block));
 786
 787   return GRUB_ERR_NONE;
 788 }
 789
 790 static struct grub_nilfs2_data *
 791 grub_nilfs2_mount (grub_disk_t disk)
 792 {
 793   struct grub_nilfs2_data *data;
 794   struct grub_nilfs2_segment_summary ss;
 795   struct grub_nilfs2_checkpoint last_checkpoint;
 796   grub_uint64_t last_pseg;
 797   grub_uint32_t nblocks;
 798   unsigned int nilfs2_block_count;
 799
 800   data = grub_malloc (sizeof (struct grub_nilfs2_data));
 801   if (!data)
 802     return 0;
 803
 804   data->disk = disk;
 805
 806   /* Read the superblock.  */
 807   grub_nilfs2_load_sb (data);
 808   if (grub_errno)
 809     goto fail;
 810
 811   nilfs2_block_count = (1 << LOG2_NILFS2_BLOCK_SIZE (data));
 812
 813   /* Read the last segment summary. */
 814   last_pseg = grub_le_to_cpu64 (data->sblock.s_last_pseg);
 815   grub_disk_read (disk, last_pseg * nilfs2_block_count, 0,
 816                   sizeof (struct grub_nilfs2_segment_summary), &ss);
 817
 818   if (grub_errno)
 819     goto fail;
 820
 821   /* Read the super root block. */
 822   nblocks = grub_le_to_cpu32 (ss.ss_nblocks);
 823   grub_disk_read (disk, (last_pseg + (nblocks - 1)) * nilfs2_block_count, 0,
 824                   sizeof (struct grub_nilfs2_super_root), &data->sroot);
 825
 826   if (grub_errno)
 827     goto fail;
 828
 829   grub_nilfs2_read_last_checkpoint (data, &last_checkpoint);
 830
 831   if (grub_errno)
 832     goto fail;
 833
 834   grub_memcpy (&data->ifile, &last_checkpoint.cp_ifile_inode,
 835                sizeof (struct grub_nilfs2_inode));
 836
 837   data->diropen.data = data;
 838   data->diropen.ino = 2;
 839   data->diropen.inode_read = 1;
 840   data->inode = &data->diropen.inode;
 841
 842   grub_nilfs2_read_inode (data, 2, data->inode);
 843
 844   return data;
 845
 846 fail:
 847   if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
 848     grub_error (GRUB_ERR_BAD_FS, "not a nilfs2 filesystem");
 849
 850   grub_free (data);
 851   return 0;
 852 }
 853
 854 static char *
 855 grub_nilfs2_read_symlink (grub_fshelp_node_t node)
 856 {
 857   char *symlink;
 858   struct grub_fshelp_node *diro = node;
 859
 860   if (!diro->inode_read)
 861     {
 862       grub_nilfs2_read_inode (diro->data, diro->ino, &diro->inode);
 863       if (grub_errno)
 864         return 0;
 865     }
 866
 867   symlink = grub_malloc (grub_le_to_cpu64 (diro->inode.i_size) + 1);
 868   if (!symlink)
 869     return 0;
 870
 871   grub_nilfs2_read_file (diro, 0, 0, 0,
 872                          grub_le_to_cpu64 (diro->inode.i_size), symlink);
 873   if (grub_errno)
 874     {
 875       grub_free (symlink);
 876       return 0;
 877     }
 878
 879   symlink[grub_le_to_cpu64 (diro->inode.i_size)] = '\0';
 880   return symlink;
 881 }
 882
 883 static int
 884 grub_nilfs2_iterate_dir (grub_fshelp_node_t dir,
 885                          grub_fshelp_iterate_dir_hook_t hook, void *hook_data)
 886 {
 887   grub_off_t fpos = 0;
 888   struct grub_fshelp_node *diro = (struct grub_fshelp_node *) dir;
 889
 890   if (!diro->inode_read)
 891     {
 892       grub_nilfs2_read_inode (diro->data, diro->ino, &diro->inode);
 893       if (grub_errno)
 894         return 0;
 895     }
 896
 897   /* Iterate files.  */
 898   while (fpos < grub_le_to_cpu64 (diro->inode.i_size))
 899     {
 900       struct grub_nilfs2_dir_entry dirent;
 901
 902       grub_nilfs2_read_file (diro, 0, 0, fpos,
 903                              sizeof (struct grub_nilfs2_dir_entry),
 904                              (char *) &dirent);
 905       if (grub_errno)
 906         return 0;
 907
 908       if (dirent.rec_len == 0)
 909         return 0;
 910
 911       if (dirent.name_len != 0)
 912         {
 913           char filename[MAX_NAMELEN + 1];
 914           struct grub_fshelp_node *fdiro;
 915           enum grub_fshelp_filetype type = GRUB_FSHELP_UNKNOWN;
 916
 917           grub_nilfs2_read_file (diro, 0, 0,
 918                                  fpos + sizeof (struct grub_nilfs2_dir_entry),
 919                                  dirent.name_len, filename);
 920           if (grub_errno)
 921             return 0;
 922
 923           fdiro = grub_malloc (sizeof (struct grub_fshelp_node));
 924           if (!fdiro)
 925             return 0;
 926
 927           fdiro->data = diro->data;
 928           fdiro->ino = grub_le_to_cpu64 (dirent.inode);
 929
 930           filename[dirent.name_len] = '\0';
 931
 932           if (dirent.file_type != NILFS_FT_UNKNOWN)
 933             {
 934               fdiro->inode_read = 0;
 935
 936               if (dirent.file_type == NILFS_FT_DIR)
 937                 type = GRUB_FSHELP_DIR;
 938               else if (dirent.file_type == NILFS_FT_SYMLINK)
 939                 type = GRUB_FSHELP_SYMLINK;
 940               else if (dirent.file_type == NILFS_FT_REG_FILE)
 941                 type = GRUB_FSHELP_REG;
 942             }
 943           else
 944             {
 945               /* The filetype can not be read from the dirent, read
 946                  the inode to get more information.  */
 947               grub_nilfs2_read_inode (diro->data,
 948                                       grub_le_to_cpu64 (dirent.inode),
 949                                       &fdiro->inode);
 950               if (grub_errno)
 951                 {
 952                   grub_free (fdiro);
 953                   return 0;
 954                 }
 955
 956               fdiro->inode_read = 1;
 957
 958               if ((grub_le_to_cpu16 (fdiro->inode.i_mode)
 959                    & FILETYPE_INO_MASK) == FILETYPE_INO_DIRECTORY)
 960                 type = GRUB_FSHELP_DIR;
 961               else if ((grub_le_to_cpu16 (fdiro->inode.i_mode)
 962                         & FILETYPE_INO_MASK) == FILETYPE_INO_SYMLINK)
 963                 type = GRUB_FSHELP_SYMLINK;
 964               else if ((grub_le_to_cpu16 (fdiro->inode.i_mode)
 965                         & FILETYPE_INO_MASK) == FILETYPE_INO_REG)
 966                 type = GRUB_FSHELP_REG;
 967             }
 968
 969           if (hook (filename, type, fdiro, hook_data))
 970             return 1;
 971         }
 972
 973       fpos += grub_le_to_cpu16 (dirent.rec_len);
 974     }
 975
 976   return 0;
 977 }
 978
 979 /* Open a file named NAME and initialize FILE.  */
 980 static grub_err_t
 981 grub_nilfs2_open (struct grub_file *file, const char *name)
 982 {
 983   struct grub_nilfs2_data *data = NULL;
 984   struct grub_fshelp_node *fdiro = 0;
 985
 986   grub_dl_ref (my_mod);
 987
 988   data = grub_nilfs2_mount (file->device->disk);
 989   if (!data)
 990     goto fail;
 991
 992   grub_fshelp_find_file (name, &data->diropen, &fdiro,
 993                          grub_nilfs2_iterate_dir, grub_nilfs2_read_symlink,
 994                          GRUB_FSHELP_REG);
 995   if (grub_errno)
 996     goto fail;
 997
 998   if (!fdiro->inode_read)
 999     {
1000       grub_nilfs2_read_inode (data, fdiro->ino, &fdiro->inode);
1001       if (grub_errno)
1002         goto fail;
1003     }
1004
1005   grub_memcpy (data->inode, &fdiro->inode, sizeof (struct grub_nilfs2_inode));
1006   grub_free (fdiro);
1007
1008   file->size = grub_le_to_cpu64 (data->inode->i_size);
1009   file->data = data;
1010   file->offset = 0;
1011
1012   return 0;
1013
1014 fail:
1015   if (fdiro != &data->diropen)
1016     grub_free (fdiro);
1017   grub_free (data);
1018
1019   grub_dl_unref (my_mod);
1020
1021   return grub_errno;
1022 }
1023
1024 static grub_err_t
1025 grub_nilfs2_close (grub_file_t file)
1026 {
1027   grub_free (file->data);
1028
1029   grub_dl_unref (my_mod);
1030
1031   return GRUB_ERR_NONE;
1032 }
1033
1034 /* Read LEN bytes data from FILE into BUF.  */
1035 static grub_ssize_t
1036 grub_nilfs2_read (grub_file_t file, char *buf, grub_size_t len)
1037 {
1038   struct grub_nilfs2_data *data = (struct grub_nilfs2_data *) file->data;
1039
1040   return grub_nilfs2_read_file (&data->diropen,
1041                                 file->read_hook, file->read_hook_data,
1042                                 file->offset, len, buf);
1043 }
1044
1045 /* Context for grub_nilfs2_dir.  */
1046 struct grub_nilfs2_dir_ctx
1047 {
1048   grub_fs_dir_hook_t hook;
1049   void *hook_data;
1050   struct grub_nilfs2_data *data;
1051 };
1052
1053 /* Helper for grub_nilfs2_dir.  */
1054 static int
1055 grub_nilfs2_dir_iter (const char *filename, enum grub_fshelp_filetype filetype,
1056                       grub_fshelp_node_t node, void *data)
1057 {
1058   struct grub_nilfs2_dir_ctx *ctx = data;
1059   struct grub_dirhook_info info;
1060
1061   grub_memset (&info, 0, sizeof (info));
1062   if (!node->inode_read)
1063     {
1064       grub_nilfs2_read_inode (ctx->data, node->ino, &node->inode);
1065       if (!grub_errno)
1066         node->inode_read = 1;
1067       grub_errno = GRUB_ERR_NONE;
1068     }
1069   if (node->inode_read)
1070     {
1071       info.mtimeset = 1;
1072       info.mtime = grub_le_to_cpu64 (node->inode.i_mtime);
1073     }
1074
1075   info.dir = ((filetype & GRUB_FSHELP_TYPE_MASK) == GRUB_FSHELP_DIR);
1076   grub_free (node);
1077   return ctx->hook (filename, &info, ctx->hook_data);
1078 }
1079
1080 static grub_err_t
1081 grub_nilfs2_dir (grub_device_t device, const char *path,
1082                  grub_fs_dir_hook_t hook, void *hook_data)
1083 {
1084   struct grub_nilfs2_dir_ctx ctx = {
1085     .hook = hook,
1086     .hook_data = hook_data
1087   };
1088   struct grub_fshelp_node *fdiro = 0;
1089
1090   grub_dl_ref (my_mod);
1091
1092   ctx.data = grub_nilfs2_mount (device->disk);
1093   if (!ctx.data)
1094     goto fail;
1095
1096   grub_fshelp_find_file (path, &ctx.data->diropen, &fdiro,
1097                          grub_nilfs2_iterate_dir, grub_nilfs2_read_symlink,
1098                          GRUB_FSHELP_DIR);
1099   if (grub_errno)
1100     goto fail;
1101
1102   grub_nilfs2_iterate_dir (fdiro, grub_nilfs2_dir_iter, &ctx);
1103
1104 fail:
1105   if (fdiro != &ctx.data->diropen)
1106     grub_free (fdiro);
1107   grub_free (ctx.data);
1108
1109   grub_dl_unref (my_mod);
1110
1111   return grub_errno;
1112 }
1113
1114 static grub_err_t
1115 grub_nilfs2_label (grub_device_t device, char **label)
1116 {
1117   struct grub_nilfs2_data *data;
1118   grub_disk_t disk = device->disk;
1119
1120   grub_dl_ref (my_mod);
1121
1122   data = grub_nilfs2_mount (disk);
1123   if (data)
1124     *label = grub_strndup (data->sblock.s_volume_name,
1125                            sizeof (data->sblock.s_volume_name));
1126   else
1127     *label = NULL;
1128
1129   grub_dl_unref (my_mod);
1130
1131   grub_free (data);
1132
1133   return grub_errno;
1134 }
1135
1136 static grub_err_t
1137 grub_nilfs2_uuid (grub_device_t device, char **uuid)
1138 {
1139   struct grub_nilfs2_data *data;
1140   grub_disk_t disk = device->disk;
1141
1142   grub_dl_ref (my_mod);
1143
1144   data = grub_nilfs2_mount (disk);
1145   if (data)
1146     {
1147       *uuid =
1148         grub_xasprintf
1149         ("%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
1150          data->sblock.s_uuid[0], data->sblock.s_uuid[1],
1151          data->sblock.s_uuid[2], data->sblock.s_uuid[3],
1152          data->sblock.s_uuid[4], data->sblock.s_uuid[5],
1153          data->sblock.s_uuid[6], data->sblock.s_uuid[7],
1154          data->sblock.s_uuid[8], data->sblock.s_uuid[9],
1155          data->sblock.s_uuid[10], data->sblock.s_uuid[11],
1156          data->sblock.s_uuid[12], data->sblock.s_uuid[13],
1157          data->sblock.s_uuid[14], data->sblock.s_uuid[15]);
1158     }
1159   else
1160     *uuid = NULL;
1161
1162   grub_dl_unref (my_mod);
1163
1164   grub_free (data);
1165
1166   return grub_errno;
1167 }
1168
1169 /* Get mtime.  */
1170 static grub_err_t
1171 grub_nilfs2_mtime (grub_device_t device, grub_int32_t * tm)
1172 {
1173   struct grub_nilfs2_data *data;
1174   grub_disk_t disk = device->disk;
1175
1176   grub_dl_ref (my_mod);
1177
1178   data = grub_nilfs2_mount (disk);
1179   if (!data)
1180     *tm = 0;
1181   else
1182     *tm = (grub_int32_t) grub_le_to_cpu64 (data->sblock.s_wtime);
1183
1184   grub_dl_unref (my_mod);
1185
1186   grub_free (data);
1187
1188   return grub_errno;
1189 }
1190 \f
1191
1192
1193 static struct grub_fs grub_nilfs2_fs = {
1194   .name = "nilfs2",
1195   .dir = grub_nilfs2_dir,
1196   .open = grub_nilfs2_open,
1197   .read = grub_nilfs2_read,
1198   .close = grub_nilfs2_close,
1199   .label = grub_nilfs2_label,
1200   .uuid = grub_nilfs2_uuid,
1201   .mtime = grub_nilfs2_mtime,
1202 #ifdef GRUB_UTIL
1203   .reserved_first_sector = 1,
1204   .blocklist_install = 0,
1205 #endif
1206   .next = 0
1207 };
1208
1209 GRUB_MOD_INIT (nilfs2)
1210 {
1211   COMPILE_TIME_ASSERT ((1 << LOG_NILFS_DAT_ENTRY_SIZE)
1212                        == sizeof (struct
1213                                   grub_nilfs2_dat_entry));
1214   COMPILE_TIME_ASSERT (1 << LOG_INODE_SIZE
1215                        == sizeof (struct grub_nilfs2_inode));
1216   grub_fs_register (&grub_nilfs2_fs);
1217   my_mod = mod;
1218 }
1219
1220 GRUB_MOD_FINI (nilfs2)
1221 {
1222   grub_fs_unregister (&grub_nilfs2_fs);
1223 }