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
 157struct f2fs_inode {
 158        __le16 i_mode;                  /* file mode */
 159        __u8 i_advise;                  /* file hints */
 160        __u8 i_inline;                  /* file inline flags */
 161        __le32 i_uid;                   /* user ID */
 162        __le32 i_gid;                   /* group ID */
 163        __le32 i_links;                 /* links count */
 164        __le64 i_size;                  /* file size in bytes */
 165        __le64 i_blocks;                /* file size in blocks */
 166        __le64 i_atime;                 /* access time */
 167        __le64 i_ctime;                 /* change time */
 168        __le64 i_mtime;                 /* modification time */
 169        __le32 i_atime_nsec;            /* access time in nano scale */
 170        __le32 i_ctime_nsec;            /* change time in nano scale */
 171        __le32 i_mtime_nsec;            /* modification time in nano scale */
 172        __le32 i_generation;            /* file version (for NFS) */
 173        __le32 i_current_depth;         /* only for directory depth */
 174        __le32 i_xattr_nid;             /* nid to save xattr */
 175        __le32 i_flags;                 /* file attributes */
 176        __le32 i_pino;                  /* parent inode number */
 177        __le32 i_namelen;               /* file name length */
 178        __u8 i_name[F2FS_NAME_LEN];     /* file name for SPOR */
 179        __u8 i_reserved2;               /* for backward compatibility */
 180
 181        struct f2fs_extent i_ext;       /* caching a largest extent */
 182
 183        __le32 i_addr[DEF_ADDRS_PER_INODE];     /* Pointers to data blocks */
 184
 185        __le32 i_nid[5];                /* direct(2), indirect(2),
 186                                                double_indirect(1) node id */
 187} __packed;
 188
 189struct direct_node {
 190        __le32 addr[ADDRS_PER_BLOCK];   /* array of data block address */
 191} __packed;
 192
 193struct indirect_node {
 194        __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 195} __packed;
 196
 197enum {
 198        COLD_BIT_SHIFT = 0,
 199        FSYNC_BIT_SHIFT,
 200        DENT_BIT_SHIFT,
 201        OFFSET_BIT_SHIFT
 202};
 203
 204struct node_footer {
 205        __le32 nid;             /* node id */
 206        __le32 ino;             /* inode nunmber */
 207        __le32 flag;            /* include cold/fsync/dentry marks and offset */
 208        __le64 cp_ver;          /* checkpoint version */
 209        __le32 next_blkaddr;    /* next node page block address */
 210} __packed;
 211
 212struct f2fs_node {
 213        /* can be one of three types: inode, direct, and indirect types */
 214        union {
 215                struct f2fs_inode i;
 216                struct direct_node dn;
 217                struct indirect_node in;
 218        };
 219        struct node_footer footer;
 220} __packed;
 221
 222/*
 223 * For NAT entries
 224 */
 225#define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
 226
 227struct f2fs_nat_entry {
 228        __u8 version;           /* latest version of cached nat entry */
 229        __le32 ino;             /* inode number */
 230        __le32 block_addr;      /* block address */
 231} __packed;
 232
 233struct f2fs_nat_block {
 234        struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
 235} __packed;
 236
 237/*
 238 * For SIT entries
 239 *
 240 * Each segment is 2MB in size by default so that a bitmap for validity of
 241 * there-in blocks should occupy 64 bytes, 512 bits.
 242 * Not allow to change this.
 243 */
 244#define SIT_VBLOCK_MAP_SIZE 64
 245#define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
 246
 247/*
 248 * Note that f2fs_sit_entry->vblocks has the following bit-field information.
 249 * [15:10] : allocation type such as CURSEG_XXXX_TYPE
 250 * [9:0] : valid block count
 251 */
 252#define SIT_VBLOCKS_SHIFT       10
 253#define SIT_VBLOCKS_MASK        ((1 << SIT_VBLOCKS_SHIFT) - 1)
 254#define GET_SIT_VBLOCKS(raw_sit)                                \
 255        (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
 256#define GET_SIT_TYPE(raw_sit)                                   \
 257        ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)  \
 258         >> SIT_VBLOCKS_SHIFT)
 259
 260struct f2fs_sit_entry {
 261        __le16 vblocks;                         /* reference above */
 262        __u8 valid_map[SIT_VBLOCK_MAP_SIZE];    /* bitmap for valid blocks */
 263        __le64 mtime;                           /* segment age for cleaning */
 264} __packed;
 265
 266struct f2fs_sit_block {
 267        struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
 268} __packed;
 269
 270/*
 271 * For segment summary
 272 *
 273 * One summary block contains exactly 512 summary entries, which represents
 274 * exactly 2MB segment by default. Not allow to change the basic units.
 275 *
 276 * NOTE: For initializing fields, you must use set_summary
 277 *
 278 * - If data page, nid represents dnode's nid
 279 * - If node page, nid represents the node page's nid.
 280 *
 281 * The ofs_in_node is used by only data page. It represents offset
 282 * from node's page's beginning to get a data block address.
 283 * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
 284 */
 285#define ENTRIES_IN_SUM          512
 286#define SUMMARY_SIZE            (7)     /* sizeof(struct summary) */
 287#define SUM_FOOTER_SIZE         (5)     /* sizeof(struct summary_footer) */
 288#define SUM_ENTRY_SIZE          (SUMMARY_SIZE * ENTRIES_IN_SUM)
 289
 290/* a summary entry for a 4KB-sized block in a segment */
 291struct f2fs_summary {
 292        __le32 nid;             /* parent node id */
 293        union {
 294                __u8 reserved[3];
 295                struct {
 296                        __u8 version;           /* node version number */
 297                        __le16 ofs_in_node;     /* block index in parent node */
 298                } __packed;
 299        };
 300} __packed;
 301
 302/* summary block type, node or data, is stored to the summary_footer */
 303#define SUM_TYPE_NODE           (1)
 304#define SUM_TYPE_DATA           (0)
 305
 306struct summary_footer {
 307        unsigned char entry_type;       /* SUM_TYPE_XXX */
 308        __u32 check_sum;                /* summary checksum */
 309} __packed;
 310
 311#define SUM_JOURNAL_SIZE        (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
 312                                SUM_ENTRY_SIZE)
 313#define NAT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 314                                sizeof(struct nat_journal_entry))
 315#define NAT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 316                                sizeof(struct nat_journal_entry))
 317#define SIT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 318                                sizeof(struct sit_journal_entry))
 319#define SIT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 320                                sizeof(struct sit_journal_entry))
 321/*
 322 * frequently updated NAT/SIT entries can be stored in the spare area in
 323 * summary blocks
 324 */
 325enum {
 326        NAT_JOURNAL = 0,
 327        SIT_JOURNAL
 328};
 329
 330struct nat_journal_entry {
 331        __le32 nid;
 332        struct f2fs_nat_entry ne;
 333} __packed;
 334
 335struct nat_journal {
 336        struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 337        __u8 reserved[NAT_JOURNAL_RESERVED];
 338} __packed;
 339
 340struct sit_journal_entry {
 341        __le32 segno;
 342        struct f2fs_sit_entry se;
 343} __packed;
 344
 345struct sit_journal {
 346        struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
 347        __u8 reserved[SIT_JOURNAL_RESERVED];
 348} __packed;
 349
 350/* 4KB-sized summary block structure */
 351struct f2fs_summary_block {
 352        struct f2fs_summary entries[ENTRIES_IN_SUM];
 353        union {
 354                __le16 n_nats;
 355                __le16 n_sits;
 356        };
 357        /* spare area is used by NAT or SIT journals */
 358        union {
 359                struct nat_journal nat_j;
 360                struct sit_journal sit_j;
 361        };
 362        struct summary_footer footer;
 363} __packed;
 364
 365/*
 366 * For directory operations
 367 */
 368#define F2FS_DOT_HASH           0
 369#define F2FS_DDOT_HASH          F2FS_DOT_HASH
 370#define F2FS_MAX_HASH           (~((0x3ULL) << 62))
 371#define F2FS_HASH_COL_BIT       ((0x1ULL) << 63)
 372
 373typedef __le32  f2fs_hash_t;
 374
 375/* One directory entry slot covers 8bytes-long file name */
 376#define F2FS_SLOT_LEN           8
 377#define F2FS_SLOT_LEN_BITS      3
 378
 379#define GET_DENTRY_SLOTS(x)     ((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
 380
 381/* the number of dentry in a block */
 382#define NR_DENTRY_IN_BLOCK      214
 383
 384/* MAX level for dir lookup */
 385#define MAX_DIR_HASH_DEPTH      63
 386
 387#define SIZE_OF_DIR_ENTRY       11      /* by byte */
 388#define SIZE_OF_DENTRY_BITMAP   ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
 389                                        BITS_PER_BYTE)
 390#define SIZE_OF_RESERVED        (PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
 391                                F2FS_SLOT_LEN) * \
 392                                NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
 393
 394/* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
 395struct f2fs_dir_entry {
 396        __le32 hash_code;       /* hash code of file name */
 397        __le32 ino;             /* inode number */
 398        __le16 name_len;        /* lengh of file name */
 399        __u8 file_type;         /* file type */
 400} __packed;
 401
 402/* 4KB-sized directory entry block */
 403struct f2fs_dentry_block {
 404        /* validity bitmap for directory entries in each block */
 405        __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
 406        __u8 reserved[SIZE_OF_RESERVED];
 407        struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
 408        __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
 409} __packed;
 410
 411/* file types used in inode_info->flags */
 412enum {
 413        F2FS_FT_UNKNOWN,
 414        F2FS_FT_REG_FILE,
 415        F2FS_FT_DIR,
 416        F2FS_FT_CHRDEV,
 417        F2FS_FT_BLKDEV,
 418        F2FS_FT_FIFO,
 419        F2FS_FT_SOCK,
 420        F2FS_FT_SYMLINK,
 421        F2FS_FT_MAX
 422};
 423
 424#endif  /* _LINUX_F2FS_FS_H */
 425