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_LOG_SECTOR_SIZE            9       /* 9 bits for 512 byte */
  19#define F2FS_LOG_SECTORS_PER_BLOCK      3       /* 4KB: F2FS_BLKSIZE */
  20#define F2FS_BLKSIZE                    4096    /* support only 4KB block */
  21#define F2FS_MAX_EXTENSION              64      /* # of extension entries */
  22
  23#define NULL_ADDR               ((block_t)0)    /* used as block_t addresses */
  24#define NEW_ADDR                ((block_t)-1)   /* used as block_t addresses */
  25
  26#define F2FS_ROOT_INO(sbi)      (sbi->root_ino_num)
  27#define F2FS_NODE_INO(sbi)      (sbi->node_ino_num)
  28#define F2FS_META_INO(sbi)      (sbi->meta_ino_num)
  29
  30/* This flag is used by node and meta inodes, and by recovery */
  31#define GFP_F2FS_ZERO   (GFP_NOFS | __GFP_ZERO)
  32
  33/*
  34 * For further optimization on multi-head logs, on-disk layout supports maximum
  35 * 16 logs by default. The number, 16, is expected to cover all the cases
  36 * enoughly. The implementaion currently uses no more than 6 logs.
  37 * Half the logs are used for nodes, and the other half are used for data.
  38 */
  39#define MAX_ACTIVE_LOGS 16
  40#define MAX_ACTIVE_NODE_LOGS    8
  41#define MAX_ACTIVE_DATA_LOGS    8
  42
  43/*
  44 * For superblock
  45 */
  46struct f2fs_super_block {
  47        __le32 magic;                   /* Magic Number */
  48        __le16 major_ver;               /* Major Version */
  49        __le16 minor_ver;               /* Minor Version */
  50        __le32 log_sectorsize;          /* log2 sector size in bytes */
  51        __le32 log_sectors_per_block;   /* log2 # of sectors per block */
  52        __le32 log_blocksize;           /* log2 block size in bytes */
  53        __le32 log_blocks_per_seg;      /* log2 # of blocks per segment */
  54        __le32 segs_per_sec;            /* # of segments per section */
  55        __le32 secs_per_zone;           /* # of sections per zone */
  56        __le32 checksum_offset;         /* checksum offset inside super block */
  57        __le64 block_count;             /* total # of user blocks */
  58        __le32 section_count;           /* total # of sections */
  59        __le32 segment_count;           /* total # of segments */
  60        __le32 segment_count_ckpt;      /* # of segments for checkpoint */
  61        __le32 segment_count_sit;       /* # of segments for SIT */
  62        __le32 segment_count_nat;       /* # of segments for NAT */
  63        __le32 segment_count_ssa;       /* # of segments for SSA */
  64        __le32 segment_count_main;      /* # of segments for main area */
  65        __le32 segment0_blkaddr;        /* start block address of segment 0 */
  66        __le32 cp_blkaddr;              /* start block address of checkpoint */
  67        __le32 sit_blkaddr;             /* start block address of SIT */
  68        __le32 nat_blkaddr;             /* start block address of NAT */
  69        __le32 ssa_blkaddr;             /* start block address of SSA */
  70        __le32 main_blkaddr;            /* start block address of main area */
  71        __le32 root_ino;                /* root inode number */
  72        __le32 node_ino;                /* node inode number */
  73        __le32 meta_ino;                /* meta inode number */
  74        __u8 uuid[16];                  /* 128-bit uuid for volume */
  75        __le16 volume_name[512];        /* volume name */
  76        __le32 extension_count;         /* # of extensions below */
  77        __u8 extension_list[F2FS_MAX_EXTENSION][8];     /* extension array */
  78} __packed;
  79
  80/*
  81 * For checkpoint
  82 */
  83#define CP_ERROR_FLAG           0x00000008
  84#define CP_COMPACT_SUM_FLAG     0x00000004
  85#define CP_ORPHAN_PRESENT_FLAG  0x00000002
  86#define CP_UMOUNT_FLAG          0x00000001
  87
  88struct f2fs_checkpoint {
  89        __le64 checkpoint_ver;          /* checkpoint block version number */
  90        __le64 user_block_count;        /* # of user blocks */
  91        __le64 valid_block_count;       /* # of valid blocks in main area */
  92        __le32 rsvd_segment_count;      /* # of reserved segments for gc */
  93        __le32 overprov_segment_count;  /* # of overprovision segments */
  94        __le32 free_segment_count;      /* # of free segments in main area */
  95
  96        /* information of current node segments */
  97        __le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
  98        __le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
  99        /* information of current data segments */
 100        __le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
 101        __le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
 102        __le32 ckpt_flags;              /* Flags : umount and journal_present */
 103        __le32 cp_pack_total_block_count;       /* total # of one cp pack */
 104        __le32 cp_pack_start_sum;       /* start block number of data summary */
 105        __le32 valid_node_count;        /* Total number of valid nodes */
 106        __le32 valid_inode_count;       /* Total number of valid inodes */
 107        __le32 next_free_nid;           /* Next free node number */
 108        __le32 sit_ver_bitmap_bytesize; /* Default value 64 */
 109        __le32 nat_ver_bitmap_bytesize; /* Default value 256 */
 110        __le32 checksum_offset;         /* checksum offset inside cp block */
 111        __le64 elapsed_time;            /* mounted time */
 112        /* allocation type of current segment */
 113        unsigned char alloc_type[MAX_ACTIVE_LOGS];
 114
 115        /* SIT and NAT version bitmap */
 116        unsigned char sit_nat_version_bitmap[1];
 117} __packed;
 118
 119/*
 120 * For orphan inode management
 121 */
 122#define F2FS_ORPHANS_PER_BLOCK  1020
 123
 124struct f2fs_orphan_block {
 125        __le32 ino[F2FS_ORPHANS_PER_BLOCK];     /* inode numbers */
 126        __le32 reserved;        /* reserved */
 127        __le16 blk_addr;        /* block index in current CP */
 128        __le16 blk_count;       /* Number of orphan inode blocks in CP */
 129        __le32 entry_count;     /* Total number of orphan nodes in current CP */
 130        __le32 check_sum;       /* CRC32 for orphan inode block */
 131} __packed;
 132
 133/*
 134 * For NODE structure
 135 */
 136struct f2fs_extent {
 137        __le32 fofs;            /* start file offset of the extent */
 138        __le32 blk_addr;        /* start block address of the extent */
 139        __le32 len;             /* lengh of the extent */
 140} __packed;
 141
 142#define F2FS_NAME_LEN           255
 143#define F2FS_INLINE_XATTR_ADDRS 50      /* 200 bytes for inline xattrs */
 144#define DEF_ADDRS_PER_INODE     923     /* Address Pointers in an Inode */
 145#define ADDRS_PER_INODE(fi)     addrs_per_inode(fi)
 146#define ADDRS_PER_BLOCK         1018    /* Address Pointers in a Direct Block */
 147#define NIDS_PER_BLOCK          1018    /* Node IDs in an Indirect Block */
 148
 149#define NODE_DIR1_BLOCK         (DEF_ADDRS_PER_INODE + 1)
 150#define NODE_DIR2_BLOCK         (DEF_ADDRS_PER_INODE + 2)
 151#define NODE_IND1_BLOCK         (DEF_ADDRS_PER_INODE + 3)
 152#define NODE_IND2_BLOCK         (DEF_ADDRS_PER_INODE + 4)
 153#define NODE_DIND_BLOCK         (DEF_ADDRS_PER_INODE + 5)
 154
 155#define F2FS_INLINE_XATTR       0x01    /* file inline xattr flag */
 156#define F2FS_INLINE_DATA        0x02    /* file inline data flag */
 157
 158#define MAX_INLINE_DATA         (sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
 159                                                F2FS_INLINE_XATTR_ADDRS - 1))
 160
 161#define INLINE_DATA_OFFSET      (PAGE_CACHE_SIZE - sizeof(struct node_footer) \
 162                        - sizeof(__le32) * (DEF_ADDRS_PER_INODE + 5 - 1))
 163
 164struct f2fs_inode {
 165        __le16 i_mode;                  /* file mode */
 166        __u8 i_advise;                  /* file hints */
 167        __u8 i_inline;                  /* file inline flags */
 168        __le32 i_uid;                   /* user ID */
 169        __le32 i_gid;                   /* group ID */
 170        __le32 i_links;                 /* links count */
 171        __le64 i_size;                  /* file size in bytes */
 172        __le64 i_blocks;                /* file size in blocks */
 173        __le64 i_atime;                 /* access time */
 174        __le64 i_ctime;                 /* change time */
 175        __le64 i_mtime;                 /* modification time */
 176        __le32 i_atime_nsec;            /* access time in nano scale */
 177        __le32 i_ctime_nsec;            /* change time in nano scale */
 178        __le32 i_mtime_nsec;            /* modification time in nano scale */
 179        __le32 i_generation;            /* file version (for NFS) */
 180        __le32 i_current_depth;         /* only for directory depth */
 181        __le32 i_xattr_nid;             /* nid to save xattr */
 182        __le32 i_flags;                 /* file attributes */
 183        __le32 i_pino;                  /* parent inode number */
 184        __le32 i_namelen;               /* file name length */
 185        __u8 i_name[F2FS_NAME_LEN];     /* file name for SPOR */
 186        __u8 i_reserved2;               /* for backward compatibility */
 187
 188        struct f2fs_extent i_ext;       /* caching a largest extent */
 189
 190        __le32 i_addr[DEF_ADDRS_PER_INODE];     /* Pointers to data blocks */
 191
 192        __le32 i_nid[5];                /* direct(2), indirect(2),
 193                                                double_indirect(1) node id */
 194} __packed;
 195
 196struct direct_node {
 197        __le32 addr[ADDRS_PER_BLOCK];   /* array of data block address */
 198} __packed;
 199
 200struct indirect_node {
 201        __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 202} __packed;
 203
 204enum {
 205        COLD_BIT_SHIFT = 0,
 206        FSYNC_BIT_SHIFT,
 207        DENT_BIT_SHIFT,
 208        OFFSET_BIT_SHIFT
 209};
 210
 211struct node_footer {
 212        __le32 nid;             /* node id */
 213        __le32 ino;             /* inode nunmber */
 214        __le32 flag;            /* include cold/fsync/dentry marks and offset */
 215        __le64 cp_ver;          /* checkpoint version */
 216        __le32 next_blkaddr;    /* next node page block address */
 217} __packed;
 218
 219struct f2fs_node {
 220        /* can be one of three types: inode, direct, and indirect types */
 221        union {
 222                struct f2fs_inode i;
 223                struct direct_node dn;
 224                struct indirect_node in;
 225        };
 226        struct node_footer footer;
 227} __packed;
 228
 229/*
 230 * For NAT entries
 231 */
 232#define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
 233
 234struct f2fs_nat_entry {
 235        __u8 version;           /* latest version of cached nat entry */
 236        __le32 ino;             /* inode number */
 237        __le32 block_addr;      /* block address */
 238} __packed;
 239
 240struct f2fs_nat_block {
 241        struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
 242} __packed;
 243
 244/*
 245 * For SIT entries
 246 *
 247 * Each segment is 2MB in size by default so that a bitmap for validity of
 248 * there-in blocks should occupy 64 bytes, 512 bits.
 249 * Not allow to change this.
 250 */
 251#define SIT_VBLOCK_MAP_SIZE 64
 252#define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
 253
 254/*
 255 * Note that f2fs_sit_entry->vblocks has the following bit-field information.
 256 * [15:10] : allocation type such as CURSEG_XXXX_TYPE
 257 * [9:0] : valid block count
 258 */
 259#define SIT_VBLOCKS_SHIFT       10
 260#define SIT_VBLOCKS_MASK        ((1 << SIT_VBLOCKS_SHIFT) - 1)
 261#define GET_SIT_VBLOCKS(raw_sit)                                \
 262        (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
 263#define GET_SIT_TYPE(raw_sit)                                   \
 264        ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)  \
 265         >> SIT_VBLOCKS_SHIFT)
 266
 267struct f2fs_sit_entry {
 268        __le16 vblocks;                         /* reference above */
 269        __u8 valid_map[SIT_VBLOCK_MAP_SIZE];    /* bitmap for valid blocks */
 270        __le64 mtime;                           /* segment age for cleaning */
 271} __packed;
 272
 273struct f2fs_sit_block {
 274        struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
 275} __packed;
 276
 277/*
 278 * For segment summary
 279 *
 280 * One summary block contains exactly 512 summary entries, which represents
 281 * exactly 2MB segment by default. Not allow to change the basic units.
 282 *
 283 * NOTE: For initializing fields, you must use set_summary
 284 *
 285 * - If data page, nid represents dnode's nid
 286 * - If node page, nid represents the node page's nid.
 287 *
 288 * The ofs_in_node is used by only data page. It represents offset
 289 * from node's page's beginning to get a data block address.
 290 * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
 291 */
 292#define ENTRIES_IN_SUM          512
 293#define SUMMARY_SIZE            (7)     /* sizeof(struct summary) */
 294#define SUM_FOOTER_SIZE         (5)     /* sizeof(struct summary_footer) */
 295#define SUM_ENTRY_SIZE          (SUMMARY_SIZE * ENTRIES_IN_SUM)
 296
 297/* a summary entry for a 4KB-sized block in a segment */
 298struct f2fs_summary {
 299        __le32 nid;             /* parent node id */
 300        union {
 301                __u8 reserved[3];
 302                struct {
 303                        __u8 version;           /* node version number */
 304                        __le16 ofs_in_node;     /* block index in parent node */
 305                } __packed;
 306        };
 307} __packed;
 308
 309/* summary block type, node or data, is stored to the summary_footer */
 310#define SUM_TYPE_NODE           (1)
 311#define SUM_TYPE_DATA           (0)
 312
 313struct summary_footer {
 314        unsigned char entry_type;       /* SUM_TYPE_XXX */
 315        __u32 check_sum;                /* summary checksum */
 316} __packed;
 317
 318#define SUM_JOURNAL_SIZE        (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
 319                                SUM_ENTRY_SIZE)
 320#define NAT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 321                                sizeof(struct nat_journal_entry))
 322#define NAT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 323                                sizeof(struct nat_journal_entry))
 324#define SIT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 325                                sizeof(struct sit_journal_entry))
 326#define SIT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 327                                sizeof(struct sit_journal_entry))
 328/*
 329 * frequently updated NAT/SIT entries can be stored in the spare area in
 330 * summary blocks
 331 */
 332enum {
 333        NAT_JOURNAL = 0,
 334        SIT_JOURNAL
 335};
 336
 337struct nat_journal_entry {
 338        __le32 nid;
 339        struct f2fs_nat_entry ne;
 340} __packed;
 341
 342struct nat_journal {
 343        struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 344        __u8 reserved[NAT_JOURNAL_RESERVED];
 345} __packed;
 346
 347struct sit_journal_entry {
 348        __le32 segno;
 349        struct f2fs_sit_entry se;
 350} __packed;
 351
 352struct sit_journal {
 353        struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
 354        __u8 reserved[SIT_JOURNAL_RESERVED];
 355} __packed;
 356
 357/* 4KB-sized summary block structure */
 358struct f2fs_summary_block {
 359        struct f2fs_summary entries[ENTRIES_IN_SUM];
 360        union {
 361                __le16 n_nats;
 362                __le16 n_sits;
 363        };
 364        /* spare area is used by NAT or SIT journals */
 365        union {
 366                struct nat_journal nat_j;
 367                struct sit_journal sit_j;
 368        };
 369        struct summary_footer footer;
 370} __packed;
 371
 372/*
 373 * For directory operations
 374 */
 375#define F2FS_DOT_HASH           0
 376#define F2FS_DDOT_HASH          F2FS_DOT_HASH
 377#define F2FS_MAX_HASH           (~((0x3ULL) << 62))
 378#define F2FS_HASH_COL_BIT       ((0x1ULL) << 63)
 379
 380typedef __le32  f2fs_hash_t;
 381
 382/* One directory entry slot covers 8bytes-long file name */
 383#define F2FS_SLOT_LEN           8
 384#define F2FS_SLOT_LEN_BITS      3
 385
 386#define GET_DENTRY_SLOTS(x)     ((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
 387
 388/* the number of dentry in a block */
 389#define NR_DENTRY_IN_BLOCK      214
 390
 391/* MAX level for dir lookup */
 392#define MAX_DIR_HASH_DEPTH      63
 393
 394#define SIZE_OF_DIR_ENTRY       11      /* by byte */
 395#define SIZE_OF_DENTRY_BITMAP   ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
 396                                        BITS_PER_BYTE)
 397#define SIZE_OF_RESERVED        (PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
 398                                F2FS_SLOT_LEN) * \
 399                                NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
 400
 401/* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
 402struct f2fs_dir_entry {
 403        __le32 hash_code;       /* hash code of file name */
 404        __le32 ino;             /* inode number */
 405        __le16 name_len;        /* lengh of file name */
 406        __u8 file_type;         /* file type */
 407} __packed;
 408
 409/* 4KB-sized directory entry block */
 410struct f2fs_dentry_block {
 411        /* validity bitmap for directory entries in each block */
 412        __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
 413        __u8 reserved[SIZE_OF_RESERVED];
 414        struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
 415        __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
 416} __packed;
 417
 418/* file types used in inode_info->flags */
 419enum {
 420        F2FS_FT_UNKNOWN,
 421        F2FS_FT_REG_FILE,
 422        F2FS_FT_DIR,
 423        F2FS_FT_CHRDEV,
 424        F2FS_FT_BLKDEV,
 425        F2FS_FT_FIFO,
 426        F2FS_FT_SOCK,
 427        F2FS_FT_SYMLINK,
 428        F2FS_FT_MAX
 429};
 430
 431#endif  /* _LINUX_F2FS_FS_H */
 432