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_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               0x0U
  24 #define NEW_ADDR                -1U
  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  */
  46 struct 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
  88 struct 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
 124 struct 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  */
 136 struct 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_MAX_NAME_LEN       256
 143 #define ADDRS_PER_INODE         923     /* Address Pointers in an Inode */
 144 #define ADDRS_PER_BLOCK         1018    /* Address Pointers in a Direct Block */
 145 #define NIDS_PER_BLOCK          1018    /* Node IDs in an Indirect Block */
 146
 147 struct f2fs_inode {
 148         __le16 i_mode;                  /* file mode */
 149         __u8 i_advise;                  /* file hints */
 150         __u8 i_reserved;                /* reserved */
 151         __le32 i_uid;                   /* user ID */
 152         __le32 i_gid;                   /* group ID */
 153         __le32 i_links;                 /* links count */
 154         __le64 i_size;                  /* file size in bytes */
 155         __le64 i_blocks;                /* file size in blocks */
 156         __le64 i_atime;                 /* access time */
 157         __le64 i_ctime;                 /* change time */
 158         __le64 i_mtime;                 /* modification time */
 159         __le32 i_atime_nsec;            /* access time in nano scale */
 160         __le32 i_ctime_nsec;            /* change time in nano scale */
 161         __le32 i_mtime_nsec;            /* modification time in nano scale */
 162         __le32 i_generation;            /* file version (for NFS) */
 163         __le32 i_current_depth;         /* only for directory depth */
 164         __le32 i_xattr_nid;             /* nid to save xattr */
 165         __le32 i_flags;                 /* file attributes */
 166         __le32 i_pino;                  /* parent inode number */
 167         __le32 i_namelen;               /* file name length */
 168         __u8 i_name[F2FS_MAX_NAME_LEN]; /* file name for SPOR */
 169
 170         struct f2fs_extent i_ext;       /* caching a largest extent */
 171
 172         __le32 i_addr[ADDRS_PER_INODE]; /* Pointers to data blocks */
 173
 174         __le32 i_nid[5];                /* direct(2), indirect(2),
 175                                                 double_indirect(1) node id */
 176 } __packed;
 177
 178 struct direct_node {
 179         __le32 addr[ADDRS_PER_BLOCK];   /* array of data block address */
 180 } __packed;
 181
 182 struct indirect_node {
 183         __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 184 } __packed;
 185
 186 enum {
 187         COLD_BIT_SHIFT = 0,
 188         FSYNC_BIT_SHIFT,
 189         DENT_BIT_SHIFT,
 190         OFFSET_BIT_SHIFT
 191 };
 192
 193 struct node_footer {
 194         __le32 nid;             /* node id */
 195         __le32 ino;             /* inode nunmber */
 196         __le32 flag;            /* include cold/fsync/dentry marks and offset */
 197         __le64 cp_ver;          /* checkpoint version */
 198         __le32 next_blkaddr;    /* next node page block address */
 199 } __packed;
 200
 201 struct f2fs_node {
 202         /* can be one of three types: inode, direct, and indirect types */
 203         union {
 204                 struct f2fs_inode i;
 205                 struct direct_node dn;
 206                 struct indirect_node in;
 207         };
 208         struct node_footer footer;
 209 } __packed;
 210
 211 /*
 212  * For NAT entries
 213  */
 214 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
 215
 216 struct f2fs_nat_entry {
 217         __u8 version;           /* latest version of cached nat entry */
 218         __le32 ino;             /* inode number */
 219         __le32 block_addr;      /* block address */
 220 } __packed;
 221
 222 struct f2fs_nat_block {
 223         struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
 224 } __packed;
 225
 226 /*
 227  * For SIT entries
 228  *
 229  * Each segment is 2MB in size by default so that a bitmap for validity of
 230  * there-in blocks should occupy 64 bytes, 512 bits.
 231  * Not allow to change this.
 232  */
 233 #define SIT_VBLOCK_MAP_SIZE 64
 234 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
 235
 236 /*
 237  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
 238  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
 239  * [9:0] : valid block count
 240  */
 241 #define SIT_VBLOCKS_SHIFT       10
 242 #define SIT_VBLOCKS_MASK        ((1 << SIT_VBLOCKS_SHIFT) - 1)
 243 #define GET_SIT_VBLOCKS(raw_sit)                                \
 244         (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
 245 #define GET_SIT_TYPE(raw_sit)                                   \
 246         ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)  \
 247          >> SIT_VBLOCKS_SHIFT)
 248
 249 struct f2fs_sit_entry {
 250         __le16 vblocks;                         /* reference above */
 251         __u8 valid_map[SIT_VBLOCK_MAP_SIZE];    /* bitmap for valid blocks */
 252         __le64 mtime;                           /* segment age for cleaning */
 253 } __packed;
 254
 255 struct f2fs_sit_block {
 256         struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
 257 } __packed;
 258
 259 /*
 260  * For segment summary
 261  *
 262  * One summary block contains exactly 512 summary entries, which represents
 263  * exactly 2MB segment by default. Not allow to change the basic units.
 264  *
 265  * NOTE: For initializing fields, you must use set_summary
 266  *
 267  * - If data page, nid represents dnode's nid
 268  * - If node page, nid represents the node page's nid.
 269  *
 270  * The ofs_in_node is used by only data page. It represents offset
 271  * from node's page's beginning to get a data block address.
 272  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
 273  */
 274 #define ENTRIES_IN_SUM          512
 275 #define SUMMARY_SIZE            (7)     /* sizeof(struct summary) */
 276 #define SUM_FOOTER_SIZE         (5)     /* sizeof(struct summary_footer) */
 277 #define SUM_ENTRY_SIZE          (SUMMARY_SIZE * ENTRIES_IN_SUM)
 278
 279 /* a summary entry for a 4KB-sized block in a segment */
 280 struct f2fs_summary {
 281         __le32 nid;             /* parent node id */
 282         union {
 283                 __u8 reserved[3];
 284                 struct {
 285                         __u8 version;           /* node version number */
 286                         __le16 ofs_in_node;     /* block index in parent node */
 287                 } __packed;
 288         };
 289 } __packed;
 290
 291 /* summary block type, node or data, is stored to the summary_footer */
 292 #define SUM_TYPE_NODE           (1)
 293 #define SUM_TYPE_DATA           (0)
 294
 295 struct summary_footer {
 296         unsigned char entry_type;       /* SUM_TYPE_XXX */
 297         __u32 check_sum;                /* summary checksum */
 298 } __packed;
 299
 300 #define SUM_JOURNAL_SIZE        (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
 301                                 SUM_ENTRY_SIZE)
 302 #define NAT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 303                                 sizeof(struct nat_journal_entry))
 304 #define NAT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 305                                 sizeof(struct nat_journal_entry))
 306 #define SIT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 307                                 sizeof(struct sit_journal_entry))
 308 #define SIT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 309                                 sizeof(struct sit_journal_entry))
 310 /*
 311  * frequently updated NAT/SIT entries can be stored in the spare area in
 312  * summary blocks
 313  */
 314 enum {
 315         NAT_JOURNAL = 0,
 316         SIT_JOURNAL
 317 };
 318
 319 struct nat_journal_entry {
 320         __le32 nid;
 321         struct f2fs_nat_entry ne;
 322 } __packed;
 323
 324 struct nat_journal {
 325         struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 326         __u8 reserved[NAT_JOURNAL_RESERVED];
 327 } __packed;
 328
 329 struct sit_journal_entry {
 330         __le32 segno;
 331         struct f2fs_sit_entry se;
 332 } __packed;
 333
 334 struct sit_journal {
 335         struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
 336         __u8 reserved[SIT_JOURNAL_RESERVED];
 337 } __packed;
 338
 339 /* 4KB-sized summary block structure */
 340 struct f2fs_summary_block {
 341         struct f2fs_summary entries[ENTRIES_IN_SUM];
 342         union {
 343                 __le16 n_nats;
 344                 __le16 n_sits;
 345         };
 346         /* spare area is used by NAT or SIT journals */
 347         union {
 348                 struct nat_journal nat_j;
 349                 struct sit_journal sit_j;
 350         };
 351         struct summary_footer footer;
 352 } __packed;
 353
 354 /*
 355  * For directory operations
 356  */
 357 #define F2FS_DOT_HASH           0
 358 #define F2FS_DDOT_HASH          F2FS_DOT_HASH
 359 #define F2FS_MAX_HASH           (~((0x3ULL) << 62))
 360 #define F2FS_HASH_COL_BIT       ((0x1ULL) << 63)
 361
 362 typedef __le32  f2fs_hash_t;
 363
 364 /* One directory entry slot covers 8bytes-long file name */
 365 #define F2FS_NAME_LEN           8
 366 #define F2FS_NAME_LEN_BITS      3
 367
 368 #define GET_DENTRY_SLOTS(x)     ((x + F2FS_NAME_LEN - 1) >> F2FS_NAME_LEN_BITS)
 369
 370 /* the number of dentry in a block */
 371 #define NR_DENTRY_IN_BLOCK      214
 372
 373 /* MAX level for dir lookup */
 374 #define MAX_DIR_HASH_DEPTH      63
 375
 376 #define SIZE_OF_DIR_ENTRY       11      /* by byte */
 377 #define SIZE_OF_DENTRY_BITMAP   ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
 378                                         BITS_PER_BYTE)
 379 #define SIZE_OF_RESERVED        (PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
 380                                 F2FS_NAME_LEN) * \
 381                                 NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
 382
 383 /* One directory entry slot representing F2FS_NAME_LEN-sized file name */
 384 struct f2fs_dir_entry {
 385         __le32 hash_code;       /* hash code of file name */
 386         __le32 ino;             /* inode number */
 387         __le16 name_len;        /* lengh of file name */
 388         __u8 file_type;         /* file type */
 389 } __packed;
 390
 391 /* 4KB-sized directory entry block */
 392 struct f2fs_dentry_block {
 393         /* validity bitmap for directory entries in each block */
 394         __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
 395         __u8 reserved[SIZE_OF_RESERVED];
 396         struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
 397         __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_NAME_LEN];
 398 } __packed;
 399
 400 /* file types used in inode_info->flags */
 401 enum {
 402         F2FS_FT_UNKNOWN,
 403         F2FS_FT_REG_FILE,
 404         F2FS_FT_DIR,
 405         F2FS_FT_CHRDEV,
 406         F2FS_FT_BLKDEV,
 407         F2FS_FT_FIFO,
 408         F2FS_FT_SOCK,
 409         F2FS_FT_SYMLINK,
 410         F2FS_FT_MAX
 411 };
 412
 413 #endif  /* _LINUX_F2FS_FS_H */