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