include/linux/f2fs_fs.h

   1 /**
   2  * include/linux/f2fs_fs.h
   3  *
   4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   5  *             http://www.samsung.com/
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #ifndef _LINUX_F2FS_FS_H
  12 #define _LINUX_F2FS_FS_H
  13
  14 #include <linux/pagemap.h>
  15 #include <linux/types.h>
  16
  17 #define F2FS_SUPER_OFFSET               1024    /* byte-size offset */
  18 #define F2FS_MIN_LOG_SECTOR_SIZE        9       /* 9 bits for 512 bytes */
  19 #define F2FS_MAX_LOG_SECTOR_SIZE        12      /* 12 bits for 4096 bytes */
  20 #define F2FS_LOG_SECTORS_PER_BLOCK      3       /* log number for sector/blk */
  21 #define F2FS_BLKSIZE                    4096    /* support only 4KB block */
  22 #define F2FS_BLKSIZE_BITS               12      /* bits for F2FS_BLKSIZE */
  23 #define F2FS_MAX_EXTENSION              64      /* # of extension entries */
  24 #define F2FS_BLK_ALIGN(x)       (((x) + F2FS_BLKSIZE - 1) / F2FS_BLKSIZE)
  25
  26 #define NULL_ADDR               ((block_t)0)    /* used as block_t addresses */
  27 #define NEW_ADDR                ((block_t)-1)   /* used as block_t addresses */
  28
  29 #define F2FS_BYTES_TO_BLK(bytes)        ((bytes) >> F2FS_BLKSIZE_BITS)
  30 #define F2FS_BLK_TO_BYTES(blk)          ((blk) << F2FS_BLKSIZE_BITS)
  31
  32 /* 0, 1(node nid), 2(meta nid) are reserved node id */
  33 #define F2FS_RESERVED_NODE_NUM          3
  34
  35 #define F2FS_ROOT_INO(sbi)      (sbi->root_ino_num)
  36 #define F2FS_NODE_INO(sbi)      (sbi->node_ino_num)
  37 #define F2FS_META_INO(sbi)      (sbi->meta_ino_num)
  38
  39 /* This flag is used by node and meta inodes, and by recovery */
  40 #define GFP_F2FS_ZERO           (GFP_NOFS | __GFP_ZERO)
  41 #define GFP_F2FS_HIGH_ZERO      (GFP_NOFS | __GFP_ZERO | __GFP_HIGHMEM)
  42
  43 /*
  44  * For further optimization on multi-head logs, on-disk layout supports maximum
  45  * 16 logs by default. The number, 16, is expected to cover all the cases
  46  * enoughly. The implementaion currently uses no more than 6 logs.
  47  * Half the logs are used for nodes, and the other half are used for data.
  48  */
  49 #define MAX_ACTIVE_LOGS 16
  50 #define MAX_ACTIVE_NODE_LOGS    8
  51 #define MAX_ACTIVE_DATA_LOGS    8
  52
  53 /*
  54  * For superblock
  55  */
  56 struct f2fs_super_block {
  57         __le32 magic;                   /* Magic Number */
  58         __le16 major_ver;               /* Major Version */
  59         __le16 minor_ver;               /* Minor Version */
  60         __le32 log_sectorsize;          /* log2 sector size in bytes */
  61         __le32 log_sectors_per_block;   /* log2 # of sectors per block */
  62         __le32 log_blocksize;           /* log2 block size in bytes */
  63         __le32 log_blocks_per_seg;      /* log2 # of blocks per segment */
  64         __le32 segs_per_sec;            /* # of segments per section */
  65         __le32 secs_per_zone;           /* # of sections per zone */
  66         __le32 checksum_offset;         /* checksum offset inside super block */
  67         __le64 block_count;             /* total # of user blocks */
  68         __le32 section_count;           /* total # of sections */
  69         __le32 segment_count;           /* total # of segments */
  70         __le32 segment_count_ckpt;      /* # of segments for checkpoint */
  71         __le32 segment_count_sit;       /* # of segments for SIT */
  72         __le32 segment_count_nat;       /* # of segments for NAT */
  73         __le32 segment_count_ssa;       /* # of segments for SSA */
  74         __le32 segment_count_main;      /* # of segments for main area */
  75         __le32 segment0_blkaddr;        /* start block address of segment 0 */
  76         __le32 cp_blkaddr;              /* start block address of checkpoint */
  77         __le32 sit_blkaddr;             /* start block address of SIT */
  78         __le32 nat_blkaddr;             /* start block address of NAT */
  79         __le32 ssa_blkaddr;             /* start block address of SSA */
  80         __le32 main_blkaddr;            /* start block address of main area */
  81         __le32 root_ino;                /* root inode number */
  82         __le32 node_ino;                /* node inode number */
  83         __le32 meta_ino;                /* meta inode number */
  84         __u8 uuid[16];                  /* 128-bit uuid for volume */
  85         __le16 volume_name[512];        /* volume name */
  86         __le32 extension_count;         /* # of extensions below */
  87         __u8 extension_list[F2FS_MAX_EXTENSION][8];     /* extension array */
  88         __le32 cp_payload;
  89 } __packed;
  90
  91 /*
  92  * For checkpoint
  93  */
  94 #define CP_FASTBOOT_FLAG        0x00000020
  95 #define CP_FSCK_FLAG            0x00000010
  96 #define CP_ERROR_FLAG           0x00000008
  97 #define CP_COMPACT_SUM_FLAG     0x00000004
  98 #define CP_ORPHAN_PRESENT_FLAG  0x00000002
  99 #define CP_UMOUNT_FLAG          0x00000001
 100
 101 #define F2FS_CP_PACKS           2       /* # of checkpoint packs */
 102
 103 struct f2fs_checkpoint {
 104         __le64 checkpoint_ver;          /* checkpoint block version number */
 105         __le64 user_block_count;        /* # of user blocks */
 106         __le64 valid_block_count;       /* # of valid blocks in main area */
 107         __le32 rsvd_segment_count;      /* # of reserved segments for gc */
 108         __le32 overprov_segment_count;  /* # of overprovision segments */
 109         __le32 free_segment_count;      /* # of free segments in main area */
 110
 111         /* information of current node segments */
 112         __le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
 113         __le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
 114         /* information of current data segments */
 115         __le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
 116         __le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
 117         __le32 ckpt_flags;              /* Flags : umount and journal_present */
 118         __le32 cp_pack_total_block_count;       /* total # of one cp pack */
 119         __le32 cp_pack_start_sum;       /* start block number of data summary */
 120         __le32 valid_node_count;        /* Total number of valid nodes */
 121         __le32 valid_inode_count;       /* Total number of valid inodes */
 122         __le32 next_free_nid;           /* Next free node number */
 123         __le32 sit_ver_bitmap_bytesize; /* Default value 64 */
 124         __le32 nat_ver_bitmap_bytesize; /* Default value 256 */
 125         __le32 checksum_offset;         /* checksum offset inside cp block */
 126         __le64 elapsed_time;            /* mounted time */
 127         /* allocation type of current segment */
 128         unsigned char alloc_type[MAX_ACTIVE_LOGS];
 129
 130         /* SIT and NAT version bitmap */
 131         unsigned char sit_nat_version_bitmap[1];
 132 } __packed;
 133
 134 /*
 135  * For orphan inode management
 136  */
 137 #define F2FS_ORPHANS_PER_BLOCK  1020
 138
 139 #define GET_ORPHAN_BLOCKS(n)    ((n + F2FS_ORPHANS_PER_BLOCK - 1) / \
 140                                         F2FS_ORPHANS_PER_BLOCK)
 141
 142 struct f2fs_orphan_block {
 143         __le32 ino[F2FS_ORPHANS_PER_BLOCK];     /* inode numbers */
 144         __le32 reserved;        /* reserved */
 145         __le16 blk_addr;        /* block index in current CP */
 146         __le16 blk_count;       /* Number of orphan inode blocks in CP */
 147         __le32 entry_count;     /* Total number of orphan nodes in current CP */
 148         __le32 check_sum;       /* CRC32 for orphan inode block */
 149 } __packed;
 150
 151 /*
 152  * For NODE structure
 153  */
 154 struct f2fs_extent {
 155         __le32 fofs;            /* start file offset of the extent */
 156         __le32 blk;             /* start block address of the extent */
 157         __le32 len;             /* lengh of the extent */
 158 } __packed;
 159
 160 #define F2FS_NAME_LEN           255
 161 #define F2FS_INLINE_XATTR_ADDRS 50      /* 200 bytes for inline xattrs */
 162 #define DEF_ADDRS_PER_INODE     923     /* Address Pointers in an Inode */
 163 #define DEF_NIDS_PER_INODE      5       /* Node IDs in an Inode */
 164 #define ADDRS_PER_INODE(fi)     addrs_per_inode(fi)
 165 #define ADDRS_PER_BLOCK         1018    /* Address Pointers in a Direct Block */
 166 #define NIDS_PER_BLOCK          1018    /* Node IDs in an Indirect Block */
 167
 168 #define ADDRS_PER_PAGE(page, fi)        \
 169         (IS_INODE(page) ? ADDRS_PER_INODE(fi) : ADDRS_PER_BLOCK)
 170
 171 #define NODE_DIR1_BLOCK         (DEF_ADDRS_PER_INODE + 1)
 172 #define NODE_DIR2_BLOCK         (DEF_ADDRS_PER_INODE + 2)
 173 #define NODE_IND1_BLOCK         (DEF_ADDRS_PER_INODE + 3)
 174 #define NODE_IND2_BLOCK         (DEF_ADDRS_PER_INODE + 4)
 175 #define NODE_DIND_BLOCK         (DEF_ADDRS_PER_INODE + 5)
 176
 177 #define F2FS_INLINE_XATTR       0x01    /* file inline xattr flag */
 178 #define F2FS_INLINE_DATA        0x02    /* file inline data flag */
 179 #define F2FS_INLINE_DENTRY      0x04    /* file inline dentry flag */
 180 #define F2FS_DATA_EXIST         0x08    /* file inline data exist flag */
 181 #define F2FS_INLINE_DOTS        0x10    /* file having implicit dot dentries */
 182
 183 #define MAX_INLINE_DATA         (sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
 184                                                 F2FS_INLINE_XATTR_ADDRS - 1))
 185
 186 struct f2fs_inode {
 187         __le16 i_mode;                  /* file mode */
 188         __u8 i_advise;                  /* file hints */
 189         __u8 i_inline;                  /* file inline flags */
 190         __le32 i_uid;                   /* user ID */
 191         __le32 i_gid;                   /* group ID */
 192         __le32 i_links;                 /* links count */
 193         __le64 i_size;                  /* file size in bytes */
 194         __le64 i_blocks;                /* file size in blocks */
 195         __le64 i_atime;                 /* access time */
 196         __le64 i_ctime;                 /* change time */
 197         __le64 i_mtime;                 /* modification time */
 198         __le32 i_atime_nsec;            /* access time in nano scale */
 199         __le32 i_ctime_nsec;            /* change time in nano scale */
 200         __le32 i_mtime_nsec;            /* modification time in nano scale */
 201         __le32 i_generation;            /* file version (for NFS) */
 202         __le32 i_current_depth;         /* only for directory depth */
 203         __le32 i_xattr_nid;             /* nid to save xattr */
 204         __le32 i_flags;                 /* file attributes */
 205         __le32 i_pino;                  /* parent inode number */
 206         __le32 i_namelen;               /* file name length */
 207         __u8 i_name[F2FS_NAME_LEN];     /* file name for SPOR */
 208         __u8 i_dir_level;               /* dentry_level for large dir */
 209
 210         struct f2fs_extent i_ext;       /* caching a largest extent */
 211
 212         __le32 i_addr[DEF_ADDRS_PER_INODE];     /* Pointers to data blocks */
 213
 214         __le32 i_nid[DEF_NIDS_PER_INODE];       /* direct(2), indirect(2),
 215                                                 double_indirect(1) node id */
 216 } __packed;
 217
 218 struct direct_node {
 219         __le32 addr[ADDRS_PER_BLOCK];   /* array of data block address */
 220 } __packed;
 221
 222 struct indirect_node {
 223         __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 224 } __packed;
 225
 226 enum {
 227         COLD_BIT_SHIFT = 0,
 228         FSYNC_BIT_SHIFT,
 229         DENT_BIT_SHIFT,
 230         OFFSET_BIT_SHIFT
 231 };
 232
 233 #define OFFSET_BIT_MASK         (0x07)  /* (0x01 << OFFSET_BIT_SHIFT) - 1 */
 234
 235 struct node_footer {
 236         __le32 nid;             /* node id */
 237         __le32 ino;             /* inode nunmber */
 238         __le32 flag;            /* include cold/fsync/dentry marks and offset */
 239         __le64 cp_ver;          /* checkpoint version */
 240         __le32 next_blkaddr;    /* next node page block address */
 241 } __packed;
 242
 243 struct f2fs_node {
 244         /* can be one of three types: inode, direct, and indirect types */
 245         union {
 246                 struct f2fs_inode i;
 247                 struct direct_node dn;
 248                 struct indirect_node in;
 249         };
 250         struct node_footer footer;
 251 } __packed;
 252
 253 /*
 254  * For NAT entries
 255  */
 256 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
 257
 258 struct f2fs_nat_entry {
 259         __u8 version;           /* latest version of cached nat entry */
 260         __le32 ino;             /* inode number */
 261         __le32 block_addr;      /* block address */
 262 } __packed;
 263
 264 struct f2fs_nat_block {
 265         struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
 266 } __packed;
 267
 268 /*
 269  * For SIT entries
 270  *
 271  * Each segment is 2MB in size by default so that a bitmap for validity of
 272  * there-in blocks should occupy 64 bytes, 512 bits.
 273  * Not allow to change this.
 274  */
 275 #define SIT_VBLOCK_MAP_SIZE 64
 276 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
 277
 278 /*
 279  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
 280  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
 281  * [9:0] : valid block count
 282  */
 283 #define SIT_VBLOCKS_SHIFT       10
 284 #define SIT_VBLOCKS_MASK        ((1 << SIT_VBLOCKS_SHIFT) - 1)
 285 #define GET_SIT_VBLOCKS(raw_sit)                                \
 286         (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
 287 #define GET_SIT_TYPE(raw_sit)                                   \
 288         ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)  \
 289          >> SIT_VBLOCKS_SHIFT)
 290
 291 struct f2fs_sit_entry {
 292         __le16 vblocks;                         /* reference above */
 293         __u8 valid_map[SIT_VBLOCK_MAP_SIZE];    /* bitmap for valid blocks */
 294         __le64 mtime;                           /* segment age for cleaning */
 295 } __packed;
 296
 297 struct f2fs_sit_block {
 298         struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
 299 } __packed;
 300
 301 /*
 302  * For segment summary
 303  *
 304  * One summary block contains exactly 512 summary entries, which represents
 305  * exactly 2MB segment by default. Not allow to change the basic units.
 306  *
 307  * NOTE: For initializing fields, you must use set_summary
 308  *
 309  * - If data page, nid represents dnode's nid
 310  * - If node page, nid represents the node page's nid.
 311  *
 312  * The ofs_in_node is used by only data page. It represents offset
 313  * from node's page's beginning to get a data block address.
 314  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
 315  */
 316 #define ENTRIES_IN_SUM          512
 317 #define SUMMARY_SIZE            (7)     /* sizeof(struct summary) */
 318 #define SUM_FOOTER_SIZE         (5)     /* sizeof(struct summary_footer) */
 319 #define SUM_ENTRY_SIZE          (SUMMARY_SIZE * ENTRIES_IN_SUM)
 320
 321 /* a summary entry for a 4KB-sized block in a segment */
 322 struct f2fs_summary {
 323         __le32 nid;             /* parent node id */
 324         union {
 325                 __u8 reserved[3];
 326                 struct {
 327                         __u8 version;           /* node version number */
 328                         __le16 ofs_in_node;     /* block index in parent node */
 329                 } __packed;
 330         };
 331 } __packed;
 332
 333 /* summary block type, node or data, is stored to the summary_footer */
 334 #define SUM_TYPE_NODE           (1)
 335 #define SUM_TYPE_DATA           (0)
 336
 337 struct summary_footer {
 338         unsigned char entry_type;       /* SUM_TYPE_XXX */
 339         __u32 check_sum;                /* summary checksum */
 340 } __packed;
 341
 342 #define SUM_JOURNAL_SIZE        (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
 343                                 SUM_ENTRY_SIZE)
 344 #define NAT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 345                                 sizeof(struct nat_journal_entry))
 346 #define NAT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 347                                 sizeof(struct nat_journal_entry))
 348 #define SIT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 349                                 sizeof(struct sit_journal_entry))
 350 #define SIT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 351                                 sizeof(struct sit_journal_entry))
 352 /*
 353  * frequently updated NAT/SIT entries can be stored in the spare area in
 354  * summary blocks
 355  */
 356 enum {
 357         NAT_JOURNAL = 0,
 358         SIT_JOURNAL
 359 };
 360
 361 struct nat_journal_entry {
 362         __le32 nid;
 363         struct f2fs_nat_entry ne;
 364 } __packed;
 365
 366 struct nat_journal {
 367         struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 368         __u8 reserved[NAT_JOURNAL_RESERVED];
 369 } __packed;
 370
 371 struct sit_journal_entry {
 372         __le32 segno;
 373         struct f2fs_sit_entry se;
 374 } __packed;
 375
 376 struct sit_journal {
 377         struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
 378         __u8 reserved[SIT_JOURNAL_RESERVED];
 379 } __packed;
 380
 381 /* 4KB-sized summary block structure */
 382 struct f2fs_summary_block {
 383         struct f2fs_summary entries[ENTRIES_IN_SUM];
 384         union {
 385                 __le16 n_nats;
 386                 __le16 n_sits;
 387         };
 388         /* spare area is used by NAT or SIT journals */
 389         union {
 390                 struct nat_journal nat_j;
 391                 struct sit_journal sit_j;
 392         };
 393         struct summary_footer footer;
 394 } __packed;
 395
 396 /*
 397  * For directory operations
 398  */
 399 #define F2FS_DOT_HASH           0
 400 #define F2FS_DDOT_HASH          F2FS_DOT_HASH
 401 #define F2FS_MAX_HASH           (~((0x3ULL) << 62))
 402 #define F2FS_HASH_COL_BIT       ((0x1ULL) << 63)
 403
 404 typedef __le32  f2fs_hash_t;
 405
 406 /* One directory entry slot covers 8bytes-long file name */
 407 #define F2FS_SLOT_LEN           8
 408 #define F2FS_SLOT_LEN_BITS      3
 409
 410 #define GET_DENTRY_SLOTS(x)     ((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
 411
 412 /* the number of dentry in a block */
 413 #define NR_DENTRY_IN_BLOCK      214
 414
 415 /* MAX level for dir lookup */
 416 #define MAX_DIR_HASH_DEPTH      63
 417
 418 /* MAX buckets in one level of dir */
 419 #define MAX_DIR_BUCKETS         (1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
 420
 421 #define SIZE_OF_DIR_ENTRY       11      /* by byte */
 422 #define SIZE_OF_DENTRY_BITMAP   ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
 423                                         BITS_PER_BYTE)
 424 #define SIZE_OF_RESERVED        (PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
 425                                 F2FS_SLOT_LEN) * \
 426                                 NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
 427
 428 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
 429 struct f2fs_dir_entry {
 430         __le32 hash_code;       /* hash code of file name */
 431         __le32 ino;             /* inode number */
 432         __le16 name_len;        /* lengh of file name */
 433         __u8 file_type;         /* file type */
 434 } __packed;
 435
 436 /* 4KB-sized directory entry block */
 437 struct f2fs_dentry_block {
 438         /* validity bitmap for directory entries in each block */
 439         __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
 440         __u8 reserved[SIZE_OF_RESERVED];
 441         struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
 442         __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
 443 } __packed;
 444
 445 /* for inline dir */
 446 #define NR_INLINE_DENTRY        (MAX_INLINE_DATA * BITS_PER_BYTE / \
 447                                 ((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
 448                                 BITS_PER_BYTE + 1))
 449 #define INLINE_DENTRY_BITMAP_SIZE       ((NR_INLINE_DENTRY + \
 450                                         BITS_PER_BYTE - 1) / BITS_PER_BYTE)
 451 #define INLINE_RESERVED_SIZE    (MAX_INLINE_DATA - \
 452                                 ((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
 453                                 NR_INLINE_DENTRY + INLINE_DENTRY_BITMAP_SIZE))
 454
 455 /* inline directory entry structure */
 456 struct f2fs_inline_dentry {
 457         __u8 dentry_bitmap[INLINE_DENTRY_BITMAP_SIZE];
 458         __u8 reserved[INLINE_RESERVED_SIZE];
 459         struct f2fs_dir_entry dentry[NR_INLINE_DENTRY];
 460         __u8 filename[NR_INLINE_DENTRY][F2FS_SLOT_LEN];
 461 } __packed;
 462
 463 /* file types used in inode_info->flags */
 464 enum {
 465         F2FS_FT_UNKNOWN,
 466         F2FS_FT_REG_FILE,
 467         F2FS_FT_DIR,
 468         F2FS_FT_CHRDEV,
 469         F2FS_FT_BLKDEV,
 470         F2FS_FT_FIFO,
 471         F2FS_FT_SOCK,
 472         F2FS_FT_SYMLINK,
 473         F2FS_FT_MAX
 474 };
 475
 476 #endif  /* _LINUX_F2FS_FS_H */