LXR linux/include/linux/f2fs

   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 */
  56struct 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
 103struct 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
 142struct 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 */
 154struct f2fs_extent {
 155        __le32 fofs;            /* start file offset of the extent */
 156        __le32 blk_addr;        /* 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
 182#define MAX_INLINE_DATA         (sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
 183                                                F2FS_INLINE_XATTR_ADDRS - 1))
 184
 185struct f2fs_inode {
 186        __le16 i_mode;                  /* file mode */
 187        __u8 i_advise;                  /* file hints */
 188        __u8 i_inline;                  /* file inline flags */
 189        __le32 i_uid;                   /* user ID */
 190        __le32 i_gid;                   /* group ID */
 191        __le32 i_links;                 /* links count */
 192        __le64 i_size;                  /* file size in bytes */
 193        __le64 i_blocks;                /* file size in blocks */
 194        __le64 i_atime;                 /* access time */
 195        __le64 i_ctime;                 /* change time */
 196        __le64 i_mtime;                 /* modification time */
 197        __le32 i_atime_nsec;            /* access time in nano scale */
 198        __le32 i_ctime_nsec;            /* change time in nano scale */
 199        __le32 i_mtime_nsec;            /* modification time in nano scale */
 200        __le32 i_generation;            /* file version (for NFS) */
 201        __le32 i_current_depth;         /* only for directory depth */
 202        __le32 i_xattr_nid;             /* nid to save xattr */
 203        __le32 i_flags;                 /* file attributes */
 204        __le32 i_pino;                  /* parent inode number */
 205        __le32 i_namelen;               /* file name length */
 206        __u8 i_name[F2FS_NAME_LEN];     /* file name for SPOR */
 207        __u8 i_dir_level;               /* dentry_level for large dir */
 208
 209        struct f2fs_extent i_ext;       /* caching a largest extent */
 210
 211        __le32 i_addr[DEF_ADDRS_PER_INODE];     /* Pointers to data blocks */
 212
 213        __le32 i_nid[DEF_NIDS_PER_INODE];       /* direct(2), indirect(2),
 214                                                double_indirect(1) node id */
 215} __packed;
 216
 217struct direct_node {
 218        __le32 addr[ADDRS_PER_BLOCK];   /* array of data block address */
 219} __packed;
 220
 221struct indirect_node {
 222        __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 223} __packed;
 224
 225enum {
 226        COLD_BIT_SHIFT = 0,
 227        FSYNC_BIT_SHIFT,
 228        DENT_BIT_SHIFT,
 229        OFFSET_BIT_SHIFT
 230};
 231
 232#define OFFSET_BIT_MASK         (0x07)  /* (0x01 << OFFSET_BIT_SHIFT) - 1 */
 233
 234struct node_footer {
 235        __le32 nid;             /* node id */
 236        __le32 ino;             /* inode nunmber */
 237        __le32 flag;            /* include cold/fsync/dentry marks and offset */
 238        __le64 cp_ver;          /* checkpoint version */
 239        __le32 next_blkaddr;    /* next node page block address */
 240} __packed;
 241
 242struct f2fs_node {
 243        /* can be one of three types: inode, direct, and indirect types */
 244        union {
 245                struct f2fs_inode i;
 246                struct direct_node dn;
 247                struct indirect_node in;
 248        };
 249        struct node_footer footer;
 250} __packed;
 251
 252/*
 253 * For NAT entries
 254 */
 255#define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
 256
 257struct f2fs_nat_entry {
 258        __u8 version;           /* latest version of cached nat entry */
 259        __le32 ino;             /* inode number */
 260        __le32 block_addr;      /* block address */
 261} __packed;
 262
 263struct f2fs_nat_block {
 264        struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
 265} __packed;
 266
 267/*
 268 * For SIT entries
 269 *
 270 * Each segment is 2MB in size by default so that a bitmap for validity of
 271 * there-in blocks should occupy 64 bytes, 512 bits.
 272 * Not allow to change this.
 273 */
 274#define SIT_VBLOCK_MAP_SIZE 64
 275#define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
 276
 277/*
 278 * Note that f2fs_sit_entry->vblocks has the following bit-field information.
 279 * [15:10] : allocation type such as CURSEG_XXXX_TYPE
 280 * [9:0] : valid block count
 281 */
 282#define SIT_VBLOCKS_SHIFT       10
 283#define SIT_VBLOCKS_MASK        ((1 << SIT_VBLOCKS_SHIFT) - 1)
 284#define GET_SIT_VBLOCKS(raw_sit)                                \
 285        (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
 286#define GET_SIT_TYPE(raw_sit)                                   \
 287        ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)  \
 288         >> SIT_VBLOCKS_SHIFT)
 289
 290struct f2fs_sit_entry {
 291        __le16 vblocks;                         /* reference above */
 292        __u8 valid_map[SIT_VBLOCK_MAP_SIZE];    /* bitmap for valid blocks */
 293        __le64 mtime;                           /* segment age for cleaning */
 294} __packed;
 295
 296struct f2fs_sit_block {
 297        struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
 298} __packed;
 299
 300/*
 301 * For segment summary
 302 *
 303 * One summary block contains exactly 512 summary entries, which represents
 304 * exactly 2MB segment by default. Not allow to change the basic units.
 305 *
 306 * NOTE: For initializing fields, you must use set_summary
 307 *
 308 * - If data page, nid represents dnode's nid
 309 * - If node page, nid represents the node page's nid.
 310 *
 311 * The ofs_in_node is used by only data page. It represents offset
 312 * from node's page's beginning to get a data block address.
 313 * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
 314 */
 315#define ENTRIES_IN_SUM          512
 316#define SUMMARY_SIZE            (7)     /* sizeof(struct summary) */
 317#define SUM_FOOTER_SIZE         (5)     /* sizeof(struct summary_footer) */
 318#define SUM_ENTRY_SIZE          (SUMMARY_SIZE * ENTRIES_IN_SUM)
 319
 320/* a summary entry for a 4KB-sized block in a segment */
 321struct f2fs_summary {
 322        __le32 nid;             /* parent node id */
 323        union {
 324                __u8 reserved[3];
 325                struct {
 326                        __u8 version;           /* node version number */
 327                        __le16 ofs_in_node;     /* block index in parent node */
 328                } __packed;
 329        };
 330} __packed;
 331
 332/* summary block type, node or data, is stored to the summary_footer */
 333#define SUM_TYPE_NODE           (1)
 334#define SUM_TYPE_DATA           (0)
 335
 336struct summary_footer {
 337        unsigned char entry_type;       /* SUM_TYPE_XXX */
 338        __u32 check_sum;                /* summary checksum */
 339} __packed;
 340
 341#define SUM_JOURNAL_SIZE        (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
 342                                SUM_ENTRY_SIZE)
 343#define NAT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 344                                sizeof(struct nat_journal_entry))
 345#define NAT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 346                                sizeof(struct nat_journal_entry))
 347#define SIT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 348                                sizeof(struct sit_journal_entry))
 349#define SIT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 350                                sizeof(struct sit_journal_entry))
 351/*
 352 * frequently updated NAT/SIT entries can be stored in the spare area in
 353 * summary blocks
 354 */
 355enum {
 356        NAT_JOURNAL = 0,
 357        SIT_JOURNAL
 358};
 359
 360struct nat_journal_entry {
 361        __le32 nid;
 362        struct f2fs_nat_entry ne;
 363} __packed;
 364
 365struct nat_journal {
 366        struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 367        __u8 reserved[NAT_JOURNAL_RESERVED];
 368} __packed;
 369
 370struct sit_journal_entry {
 371        __le32 segno;
 372        struct f2fs_sit_entry se;
 373} __packed;
 374
 375struct sit_journal {
 376        struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
 377        __u8 reserved[SIT_JOURNAL_RESERVED];
 378} __packed;
 379
 380/* 4KB-sized summary block structure */
 381struct f2fs_summary_block {
 382        struct f2fs_summary entries[ENTRIES_IN_SUM];
 383        union {
 384                __le16 n_nats;
 385                __le16 n_sits;
 386        };
 387        /* spare area is used by NAT or SIT journals */
 388        union {
 389                struct nat_journal nat_j;
 390                struct sit_journal sit_j;
 391        };
 392        struct summary_footer footer;
 393} __packed;
 394
 395/*
 396 * For directory operations
 397 */
 398#define F2FS_DOT_HASH           0
 399#define F2FS_DDOT_HASH          F2FS_DOT_HASH
 400#define F2FS_MAX_HASH           (~((0x3ULL) << 62))
 401#define F2FS_HASH_COL_BIT       ((0x1ULL) << 63)
 402
 403typedef __le32  f2fs_hash_t;
 404
 405/* One directory entry slot covers 8bytes-long file name */
 406#define F2FS_SLOT_LEN           8
 407#define F2FS_SLOT_LEN_BITS      3
 408
 409#define GET_DENTRY_SLOTS(x)     ((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
 410
 411/* the number of dentry in a block */
 412#define NR_DENTRY_IN_BLOCK      214
 413
 414/* MAX level for dir lookup */
 415#define MAX_DIR_HASH_DEPTH      63
 416
 417/* MAX buckets in one level of dir */
 418#define MAX_DIR_BUCKETS         (1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
 419
 420#define SIZE_OF_DIR_ENTRY       11      /* by byte */
 421#define SIZE_OF_DENTRY_BITMAP   ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
 422                                        BITS_PER_BYTE)
 423#define SIZE_OF_RESERVED        (PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
 424                                F2FS_SLOT_LEN) * \
 425                                NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
 426
 427/* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
 428struct f2fs_dir_entry {
 429        __le32 hash_code;       /* hash code of file name */
 430        __le32 ino;             /* inode number */
 431        __le16 name_len;        /* lengh of file name */
 432        __u8 file_type;         /* file type */
 433} __packed;
 434
 435/* 4KB-sized directory entry block */
 436struct f2fs_dentry_block {
 437        /* validity bitmap for directory entries in each block */
 438        __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
 439        __u8 reserved[SIZE_OF_RESERVED];
 440        struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
 441        __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
 442} __packed;
 443
 444/* for inline dir */
 445#define NR_INLINE_DENTRY        (MAX_INLINE_DATA * BITS_PER_BYTE / \
 446                                ((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
 447                                BITS_PER_BYTE + 1))
 448#define INLINE_DENTRY_BITMAP_SIZE       ((NR_INLINE_DENTRY + \
 449                                        BITS_PER_BYTE - 1) / BITS_PER_BYTE)
 450#define INLINE_RESERVED_SIZE    (MAX_INLINE_DATA - \
 451                                ((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
 452                                NR_INLINE_DENTRY + INLINE_DENTRY_BITMAP_SIZE))
 453
 454/* inline directory entry structure */
 455struct f2fs_inline_dentry {
 456        __u8 dentry_bitmap[INLINE_DENTRY_BITMAP_SIZE];
 457        __u8 reserved[INLINE_RESERVED_SIZE];
 458        struct f2fs_dir_entry dentry[NR_INLINE_DENTRY];
 459        __u8 filename[NR_INLINE_DENTRY][F2FS_SLOT_LEN];
 460} __packed;
 461
 462/* file types used in inode_info->flags */
 463enum {
 464        F2FS_FT_UNKNOWN,
 465        F2FS_FT_REG_FILE,
 466        F2FS_FT_DIR,
 467        F2FS_FT_CHRDEV,
 468        F2FS_FT_BLKDEV,
 469        F2FS_FT_FIFO,
 470        F2FS_FT_SOCK,
 471        F2FS_FT_SYMLINK,
 472        F2FS_FT_MAX
 473};
 474
 475#endif  /* _LINUX_F2FS_FS_H */
 476