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               ((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  */
  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_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
 164 struct 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
 196 struct direct_node {
 197         __le32 addr[ADDRS_PER_BLOCK];   /* array of data block address */
 198 } __packed;
 199
 200 struct indirect_node {
 201         __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 202 } __packed;
 203
 204 enum {
 205         COLD_BIT_SHIFT = 0,
 206         FSYNC_BIT_SHIFT,
 207         DENT_BIT_SHIFT,
 208         OFFSET_BIT_SHIFT
 209 };
 210
 211 struct 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
 219 struct 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
 234 struct 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
 240 struct 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
 267 struct 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
 273 struct 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 */
 298 struct 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
 313 struct 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  */
 332 enum {
 333         NAT_JOURNAL = 0,
 334         SIT_JOURNAL
 335 };
 336
 337 struct nat_journal_entry {
 338         __le32 nid;
 339         struct f2fs_nat_entry ne;
 340 } __packed;
 341
 342 struct nat_journal {
 343         struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 344         __u8 reserved[NAT_JOURNAL_RESERVED];
 345 } __packed;
 346
 347 struct sit_journal_entry {
 348         __le32 segno;
 349         struct f2fs_sit_entry se;
 350 } __packed;
 351
 352 struct 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 */
 358 struct 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
 380 typedef __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 */
 402 struct 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 */
 410 struct 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 */
 419 enum {
 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 */