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 #define F2FS_BLK_ALIGN(x)       (((x) + F2FS_BLKSIZE - 1) / F2FS_BLKSIZE)
  23
  24 #define NULL_ADDR               ((block_t)0)    /* used as block_t addresses */
  25 #define NEW_ADDR                ((block_t)-1)   /* used as block_t addresses */
  26
  27 /* 0, 1(node nid), 2(meta nid) are reserved node id */
  28 #define F2FS_RESERVED_NODE_NUM          3
  29
  30 #define F2FS_ROOT_INO(sbi)      (sbi->root_ino_num)
  31 #define F2FS_NODE_INO(sbi)      (sbi->node_ino_num)
  32 #define F2FS_META_INO(sbi)      (sbi->meta_ino_num)
  33
  34 /* This flag is used by node and meta inodes, and by recovery */
  35 #define GFP_F2FS_ZERO   (GFP_NOFS | __GFP_ZERO)
  36
  37 /*
  38  * For further optimization on multi-head logs, on-disk layout supports maximum
  39  * 16 logs by default. The number, 16, is expected to cover all the cases
  40  * enoughly. The implementaion currently uses no more than 6 logs.
  41  * Half the logs are used for nodes, and the other half are used for data.
  42  */
  43 #define MAX_ACTIVE_LOGS 16
  44 #define MAX_ACTIVE_NODE_LOGS    8
  45 #define MAX_ACTIVE_DATA_LOGS    8
  46
  47 /*
  48  * For superblock
  49  */
  50 struct f2fs_super_block {
  51         __le32 magic;                   /* Magic Number */
  52         __le16 major_ver;               /* Major Version */
  53         __le16 minor_ver;               /* Minor Version */
  54         __le32 log_sectorsize;          /* log2 sector size in bytes */
  55         __le32 log_sectors_per_block;   /* log2 # of sectors per block */
  56         __le32 log_blocksize;           /* log2 block size in bytes */
  57         __le32 log_blocks_per_seg;      /* log2 # of blocks per segment */
  58         __le32 segs_per_sec;            /* # of segments per section */
  59         __le32 secs_per_zone;           /* # of sections per zone */
  60         __le32 checksum_offset;         /* checksum offset inside super block */
  61         __le64 block_count;             /* total # of user blocks */
  62         __le32 section_count;           /* total # of sections */
  63         __le32 segment_count;           /* total # of segments */
  64         __le32 segment_count_ckpt;      /* # of segments for checkpoint */
  65         __le32 segment_count_sit;       /* # of segments for SIT */
  66         __le32 segment_count_nat;       /* # of segments for NAT */
  67         __le32 segment_count_ssa;       /* # of segments for SSA */
  68         __le32 segment_count_main;      /* # of segments for main area */
  69         __le32 segment0_blkaddr;        /* start block address of segment 0 */
  70         __le32 cp_blkaddr;              /* start block address of checkpoint */
  71         __le32 sit_blkaddr;             /* start block address of SIT */
  72         __le32 nat_blkaddr;             /* start block address of NAT */
  73         __le32 ssa_blkaddr;             /* start block address of SSA */
  74         __le32 main_blkaddr;            /* start block address of main area */
  75         __le32 root_ino;                /* root inode number */
  76         __le32 node_ino;                /* node inode number */
  77         __le32 meta_ino;                /* meta inode number */
  78         __u8 uuid[16];                  /* 128-bit uuid for volume */
  79         __le16 volume_name[512];        /* volume name */
  80         __le32 extension_count;         /* # of extensions below */
  81         __u8 extension_list[F2FS_MAX_EXTENSION][8];     /* extension array */
  82         __le32 cp_payload;
  83 } __packed;
  84
  85 /*
  86  * For checkpoint
  87  */
  88 #define CP_ERROR_FLAG           0x00000008
  89 #define CP_COMPACT_SUM_FLAG     0x00000004
  90 #define CP_ORPHAN_PRESENT_FLAG  0x00000002
  91 #define CP_UMOUNT_FLAG          0x00000001
  92
  93 #define F2FS_CP_PACKS           2       /* # of checkpoint packs */
  94
  95 struct f2fs_checkpoint {
  96         __le64 checkpoint_ver;          /* checkpoint block version number */
  97         __le64 user_block_count;        /* # of user blocks */
  98         __le64 valid_block_count;       /* # of valid blocks in main area */
  99         __le32 rsvd_segment_count;      /* # of reserved segments for gc */
 100         __le32 overprov_segment_count;  /* # of overprovision segments */
 101         __le32 free_segment_count;      /* # of free segments in main area */
 102
 103         /* information of current node segments */
 104         __le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
 105         __le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
 106         /* information of current data segments */
 107         __le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
 108         __le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
 109         __le32 ckpt_flags;              /* Flags : umount and journal_present */
 110         __le32 cp_pack_total_block_count;       /* total # of one cp pack */
 111         __le32 cp_pack_start_sum;       /* start block number of data summary */
 112         __le32 valid_node_count;        /* Total number of valid nodes */
 113         __le32 valid_inode_count;       /* Total number of valid inodes */
 114         __le32 next_free_nid;           /* Next free node number */
 115         __le32 sit_ver_bitmap_bytesize; /* Default value 64 */
 116         __le32 nat_ver_bitmap_bytesize; /* Default value 256 */
 117         __le32 checksum_offset;         /* checksum offset inside cp block */
 118         __le64 elapsed_time;            /* mounted time */
 119         /* allocation type of current segment */
 120         unsigned char alloc_type[MAX_ACTIVE_LOGS];
 121
 122         /* SIT and NAT version bitmap */
 123         unsigned char sit_nat_version_bitmap[1];
 124 } __packed;
 125
 126 /*
 127  * For orphan inode management
 128  */
 129 #define F2FS_ORPHANS_PER_BLOCK  1020
 130
 131 #define GET_ORPHAN_BLOCKS(n)    ((n + F2FS_ORPHANS_PER_BLOCK - 1) / \
 132                                         F2FS_ORPHANS_PER_BLOCK)
 133
 134 struct f2fs_orphan_block {
 135         __le32 ino[F2FS_ORPHANS_PER_BLOCK];     /* inode numbers */
 136         __le32 reserved;        /* reserved */
 137         __le16 blk_addr;        /* block index in current CP */
 138         __le16 blk_count;       /* Number of orphan inode blocks in CP */
 139         __le32 entry_count;     /* Total number of orphan nodes in current CP */
 140         __le32 check_sum;       /* CRC32 for orphan inode block */
 141 } __packed;
 142
 143 /*
 144  * For NODE structure
 145  */
 146 struct f2fs_extent {
 147         __le32 fofs;            /* start file offset of the extent */
 148         __le32 blk_addr;        /* start block address of the extent */
 149         __le32 len;             /* lengh of the extent */
 150 } __packed;
 151
 152 #define F2FS_NAME_LEN           255
 153 #define F2FS_INLINE_XATTR_ADDRS 50      /* 200 bytes for inline xattrs */
 154 #define DEF_ADDRS_PER_INODE     923     /* Address Pointers in an Inode */
 155 #define DEF_NIDS_PER_INODE      5       /* Node IDs in an Inode */
 156 #define ADDRS_PER_INODE(fi)     addrs_per_inode(fi)
 157 #define ADDRS_PER_BLOCK         1018    /* Address Pointers in a Direct Block */
 158 #define NIDS_PER_BLOCK          1018    /* Node IDs in an Indirect Block */
 159
 160 #define ADDRS_PER_PAGE(page, fi)        \
 161         (IS_INODE(page) ? ADDRS_PER_INODE(fi) : ADDRS_PER_BLOCK)
 162
 163 #define NODE_DIR1_BLOCK         (DEF_ADDRS_PER_INODE + 1)
 164 #define NODE_DIR2_BLOCK         (DEF_ADDRS_PER_INODE + 2)
 165 #define NODE_IND1_BLOCK         (DEF_ADDRS_PER_INODE + 3)
 166 #define NODE_IND2_BLOCK         (DEF_ADDRS_PER_INODE + 4)
 167 #define NODE_DIND_BLOCK         (DEF_ADDRS_PER_INODE + 5)
 168
 169 #define F2FS_INLINE_XATTR       0x01    /* file inline xattr flag */
 170 #define F2FS_INLINE_DATA        0x02    /* file inline data flag */
 171
 172 #define MAX_INLINE_DATA         (sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
 173                                                 F2FS_INLINE_XATTR_ADDRS - 1))
 174
 175 #define INLINE_DATA_OFFSET      (PAGE_CACHE_SIZE - sizeof(struct node_footer) -\
 176                                 sizeof(__le32) * (DEF_ADDRS_PER_INODE + \
 177                                 DEF_NIDS_PER_INODE - 1))
 178
 179 struct f2fs_inode {
 180         __le16 i_mode;                  /* file mode */
 181         __u8 i_advise;                  /* file hints */
 182         __u8 i_inline;                  /* file inline flags */
 183         __le32 i_uid;                   /* user ID */
 184         __le32 i_gid;                   /* group ID */
 185         __le32 i_links;                 /* links count */
 186         __le64 i_size;                  /* file size in bytes */
 187         __le64 i_blocks;                /* file size in blocks */
 188         __le64 i_atime;                 /* access time */
 189         __le64 i_ctime;                 /* change time */
 190         __le64 i_mtime;                 /* modification time */
 191         __le32 i_atime_nsec;            /* access time in nano scale */
 192         __le32 i_ctime_nsec;            /* change time in nano scale */
 193         __le32 i_mtime_nsec;            /* modification time in nano scale */
 194         __le32 i_generation;            /* file version (for NFS) */
 195         __le32 i_current_depth;         /* only for directory depth */
 196         __le32 i_xattr_nid;             /* nid to save xattr */
 197         __le32 i_flags;                 /* file attributes */
 198         __le32 i_pino;                  /* parent inode number */
 199         __le32 i_namelen;               /* file name length */
 200         __u8 i_name[F2FS_NAME_LEN];     /* file name for SPOR */
 201         __u8 i_dir_level;               /* dentry_level for large dir */
 202
 203         struct f2fs_extent i_ext;       /* caching a largest extent */
 204
 205         __le32 i_addr[DEF_ADDRS_PER_INODE];     /* Pointers to data blocks */
 206
 207         __le32 i_nid[DEF_NIDS_PER_INODE];       /* direct(2), indirect(2),
 208                                                 double_indirect(1) node id */
 209 } __packed;
 210
 211 struct direct_node {
 212         __le32 addr[ADDRS_PER_BLOCK];   /* array of data block address */
 213 } __packed;
 214
 215 struct indirect_node {
 216         __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 217 } __packed;
 218
 219 enum {
 220         COLD_BIT_SHIFT = 0,
 221         FSYNC_BIT_SHIFT,
 222         DENT_BIT_SHIFT,
 223         OFFSET_BIT_SHIFT
 224 };
 225
 226 struct node_footer {
 227         __le32 nid;             /* node id */
 228         __le32 ino;             /* inode nunmber */
 229         __le32 flag;            /* include cold/fsync/dentry marks and offset */
 230         __le64 cp_ver;          /* checkpoint version */
 231         __le32 next_blkaddr;    /* next node page block address */
 232 } __packed;
 233
 234 struct f2fs_node {
 235         /* can be one of three types: inode, direct, and indirect types */
 236         union {
 237                 struct f2fs_inode i;
 238                 struct direct_node dn;
 239                 struct indirect_node in;
 240         };
 241         struct node_footer footer;
 242 } __packed;
 243
 244 /*
 245  * For NAT entries
 246  */
 247 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
 248
 249 struct f2fs_nat_entry {
 250         __u8 version;           /* latest version of cached nat entry */
 251         __le32 ino;             /* inode number */
 252         __le32 block_addr;      /* block address */
 253 } __packed;
 254
 255 struct f2fs_nat_block {
 256         struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
 257 } __packed;
 258
 259 /*
 260  * For SIT entries
 261  *
 262  * Each segment is 2MB in size by default so that a bitmap for validity of
 263  * there-in blocks should occupy 64 bytes, 512 bits.
 264  * Not allow to change this.
 265  */
 266 #define SIT_VBLOCK_MAP_SIZE 64
 267 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
 268
 269 /*
 270  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
 271  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
 272  * [9:0] : valid block count
 273  */
 274 #define SIT_VBLOCKS_SHIFT       10
 275 #define SIT_VBLOCKS_MASK        ((1 << SIT_VBLOCKS_SHIFT) - 1)
 276 #define GET_SIT_VBLOCKS(raw_sit)                                \
 277         (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
 278 #define GET_SIT_TYPE(raw_sit)                                   \
 279         ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)  \
 280          >> SIT_VBLOCKS_SHIFT)
 281
 282 struct f2fs_sit_entry {
 283         __le16 vblocks;                         /* reference above */
 284         __u8 valid_map[SIT_VBLOCK_MAP_SIZE];    /* bitmap for valid blocks */
 285         __le64 mtime;                           /* segment age for cleaning */
 286 } __packed;
 287
 288 struct f2fs_sit_block {
 289         struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
 290 } __packed;
 291
 292 /*
 293  * For segment summary
 294  *
 295  * One summary block contains exactly 512 summary entries, which represents
 296  * exactly 2MB segment by default. Not allow to change the basic units.
 297  *
 298  * NOTE: For initializing fields, you must use set_summary
 299  *
 300  * - If data page, nid represents dnode's nid
 301  * - If node page, nid represents the node page's nid.
 302  *
 303  * The ofs_in_node is used by only data page. It represents offset
 304  * from node's page's beginning to get a data block address.
 305  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
 306  */
 307 #define ENTRIES_IN_SUM          512
 308 #define SUMMARY_SIZE            (7)     /* sizeof(struct summary) */
 309 #define SUM_FOOTER_SIZE         (5)     /* sizeof(struct summary_footer) */
 310 #define SUM_ENTRY_SIZE          (SUMMARY_SIZE * ENTRIES_IN_SUM)
 311
 312 /* a summary entry for a 4KB-sized block in a segment */
 313 struct f2fs_summary {
 314         __le32 nid;             /* parent node id */
 315         union {
 316                 __u8 reserved[3];
 317                 struct {
 318                         __u8 version;           /* node version number */
 319                         __le16 ofs_in_node;     /* block index in parent node */
 320                 } __packed;
 321         };
 322 } __packed;
 323
 324 /* summary block type, node or data, is stored to the summary_footer */
 325 #define SUM_TYPE_NODE           (1)
 326 #define SUM_TYPE_DATA           (0)
 327
 328 struct summary_footer {
 329         unsigned char entry_type;       /* SUM_TYPE_XXX */
 330         __u32 check_sum;                /* summary checksum */
 331 } __packed;
 332
 333 #define SUM_JOURNAL_SIZE        (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
 334                                 SUM_ENTRY_SIZE)
 335 #define NAT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 336                                 sizeof(struct nat_journal_entry))
 337 #define NAT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 338                                 sizeof(struct nat_journal_entry))
 339 #define SIT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 340                                 sizeof(struct sit_journal_entry))
 341 #define SIT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 342                                 sizeof(struct sit_journal_entry))
 343 /*
 344  * frequently updated NAT/SIT entries can be stored in the spare area in
 345  * summary blocks
 346  */
 347 enum {
 348         NAT_JOURNAL = 0,
 349         SIT_JOURNAL
 350 };
 351
 352 struct nat_journal_entry {
 353         __le32 nid;
 354         struct f2fs_nat_entry ne;
 355 } __packed;
 356
 357 struct nat_journal {
 358         struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 359         __u8 reserved[NAT_JOURNAL_RESERVED];
 360 } __packed;
 361
 362 struct sit_journal_entry {
 363         __le32 segno;
 364         struct f2fs_sit_entry se;
 365 } __packed;
 366
 367 struct sit_journal {
 368         struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
 369         __u8 reserved[SIT_JOURNAL_RESERVED];
 370 } __packed;
 371
 372 /* 4KB-sized summary block structure */
 373 struct f2fs_summary_block {
 374         struct f2fs_summary entries[ENTRIES_IN_SUM];
 375         union {
 376                 __le16 n_nats;
 377                 __le16 n_sits;
 378         };
 379         /* spare area is used by NAT or SIT journals */
 380         union {
 381                 struct nat_journal nat_j;
 382                 struct sit_journal sit_j;
 383         };
 384         struct summary_footer footer;
 385 } __packed;
 386
 387 /*
 388  * For directory operations
 389  */
 390 #define F2FS_DOT_HASH           0
 391 #define F2FS_DDOT_HASH          F2FS_DOT_HASH
 392 #define F2FS_MAX_HASH           (~((0x3ULL) << 62))
 393 #define F2FS_HASH_COL_BIT       ((0x1ULL) << 63)
 394
 395 typedef __le32  f2fs_hash_t;
 396
 397 /* One directory entry slot covers 8bytes-long file name */
 398 #define F2FS_SLOT_LEN           8
 399 #define F2FS_SLOT_LEN_BITS      3
 400
 401 #define GET_DENTRY_SLOTS(x)     ((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
 402
 403 /* the number of dentry in a block */
 404 #define NR_DENTRY_IN_BLOCK      214
 405
 406 /* MAX level for dir lookup */
 407 #define MAX_DIR_HASH_DEPTH      63
 408
 409 /* MAX buckets in one level of dir */
 410 #define MAX_DIR_BUCKETS         (1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
 411
 412 #define SIZE_OF_DIR_ENTRY       11      /* by byte */
 413 #define SIZE_OF_DENTRY_BITMAP   ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
 414                                         BITS_PER_BYTE)
 415 #define SIZE_OF_RESERVED        (PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
 416                                 F2FS_SLOT_LEN) * \
 417                                 NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
 418
 419 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
 420 struct f2fs_dir_entry {
 421         __le32 hash_code;       /* hash code of file name */
 422         __le32 ino;             /* inode number */
 423         __le16 name_len;        /* lengh of file name */
 424         __u8 file_type;         /* file type */
 425 } __packed;
 426
 427 /* 4KB-sized directory entry block */
 428 struct f2fs_dentry_block {
 429         /* validity bitmap for directory entries in each block */
 430         __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
 431         __u8 reserved[SIZE_OF_RESERVED];
 432         struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
 433         __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
 434 } __packed;
 435
 436 /* file types used in inode_info->flags */
 437 enum {
 438         F2FS_FT_UNKNOWN,
 439         F2FS_FT_REG_FILE,
 440         F2FS_FT_DIR,
 441         F2FS_FT_CHRDEV,
 442         F2FS_FT_BLKDEV,
 443         F2FS_FT_FIFO,
 444         F2FS_FT_SOCK,
 445         F2FS_FT_SYMLINK,
 446         F2FS_FT_MAX
 447 };
 448
 449 #endif  /* _LINUX_F2FS_FS_H */