include/linux/f2fs_fs.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 /**
   3  * include/linux/f2fs_fs.h
   4  *
   5  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   6  *             http://www.samsung.com/
   7  */
   8 #ifndef _LINUX_F2FS_FS_H
   9 #define _LINUX_F2FS_FS_H
  10
  11 #include <linux/pagemap.h>
  12 #include <linux/types.h>
  13
  14 #define F2FS_SUPER_OFFSET               1024    /* byte-size offset */
  15 #define F2FS_MIN_LOG_SECTOR_SIZE        9       /* 9 bits for 512 bytes */
  16 #define F2FS_MAX_LOG_SECTOR_SIZE        PAGE_SHIFT      /* Max is Block Size */
  17 #define F2FS_LOG_SECTORS_PER_BLOCK      (PAGE_SHIFT - 9) /* log number for sector/blk */
  18 #define F2FS_BLKSIZE                    PAGE_SIZE /* support only block == page */
  19 #define F2FS_BLKSIZE_BITS               PAGE_SHIFT /* bits for F2FS_BLKSIZE */
  20 #define F2FS_MAX_EXTENSION              64      /* # of extension entries */
  21 #define F2FS_EXTENSION_LEN              8       /* max size of extension */
  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 #define COMPRESS_ADDR           ((block_t)-2)   /* used as compressed data flag */
  26
  27 #define F2FS_BLKSIZE_MASK               (F2FS_BLKSIZE - 1)
  28 #define F2FS_BYTES_TO_BLK(bytes)        ((unsigned long long)(bytes) >> F2FS_BLKSIZE_BITS)
  29 #define F2FS_BLK_TO_BYTES(blk)          ((unsigned long long)(blk) << F2FS_BLKSIZE_BITS)
  30 #define F2FS_BLK_END_BYTES(blk)         (F2FS_BLK_TO_BYTES(blk + 1) - 1)
  31 #define F2FS_BLK_ALIGN(x)               (F2FS_BYTES_TO_BLK((x) + F2FS_BLKSIZE - 1))
  32
  33 /* 0, 1(node nid), 2(meta nid) are reserved node id */
  34 #define F2FS_RESERVED_NODE_NUM          3
  35
  36 #define F2FS_ROOT_INO(sbi)      ((sbi)->root_ino_num)
  37 #define F2FS_NODE_INO(sbi)      ((sbi)->node_ino_num)
  38 #define F2FS_META_INO(sbi)      ((sbi)->meta_ino_num)
  39 #define F2FS_COMPRESS_INO(sbi)  (NM_I(sbi)->max_nid)
  40
  41 #define F2FS_MAX_QUOTAS         3
  42
  43 #define F2FS_ENC_UTF8_12_1      1
  44
  45 /* This flag is used by node and meta inodes, and by recovery */
  46 #define GFP_F2FS_ZERO           (GFP_NOFS | __GFP_ZERO)
  47
  48 /*
  49  * For further optimization on multi-head logs, on-disk layout supports maximum
  50  * 16 logs by default. The number, 16, is expected to cover all the cases
  51  * enoughly. The implementaion currently uses no more than 6 logs.
  52  * Half the logs are used for nodes, and the other half are used for data.
  53  */
  54 #define MAX_ACTIVE_LOGS 16
  55 #define MAX_ACTIVE_NODE_LOGS    8
  56 #define MAX_ACTIVE_DATA_LOGS    8
  57
  58 #define VERSION_LEN     256
  59 #define MAX_VOLUME_NAME         512
  60 #define MAX_PATH_LEN            64
  61 #define MAX_DEVICES             8
  62
  63 /*
  64  * For superblock
  65  */
  66 struct f2fs_device {
  67         __u8 path[MAX_PATH_LEN];
  68         __le32 total_segments;
  69 } __packed;
  70
  71 /* reason of stop_checkpoint */
  72 enum stop_cp_reason {
  73         STOP_CP_REASON_SHUTDOWN,
  74         STOP_CP_REASON_FAULT_INJECT,
  75         STOP_CP_REASON_META_PAGE,
  76         STOP_CP_REASON_WRITE_FAIL,
  77         STOP_CP_REASON_CORRUPTED_SUMMARY,
  78         STOP_CP_REASON_UPDATE_INODE,
  79         STOP_CP_REASON_FLUSH_FAIL,
  80         STOP_CP_REASON_NO_SEGMENT,
  81         STOP_CP_REASON_MAX,
  82 };
  83
  84 #define MAX_STOP_REASON                 32
  85
  86 /* detail reason for EFSCORRUPTED */
  87 enum f2fs_error {
  88         ERROR_CORRUPTED_CLUSTER,
  89         ERROR_FAIL_DECOMPRESSION,
  90         ERROR_INVALID_BLKADDR,
  91         ERROR_CORRUPTED_DIRENT,
  92         ERROR_CORRUPTED_INODE,
  93         ERROR_INCONSISTENT_SUMMARY,
  94         ERROR_INCONSISTENT_FOOTER,
  95         ERROR_INCONSISTENT_SUM_TYPE,
  96         ERROR_CORRUPTED_JOURNAL,
  97         ERROR_INCONSISTENT_NODE_COUNT,
  98         ERROR_INCONSISTENT_BLOCK_COUNT,
  99         ERROR_INVALID_CURSEG,
 100         ERROR_INCONSISTENT_SIT,
 101         ERROR_CORRUPTED_VERITY_XATTR,
 102         ERROR_CORRUPTED_XATTR,
 103         ERROR_INVALID_NODE_REFERENCE,
 104         ERROR_INCONSISTENT_NAT,
 105         ERROR_MAX,
 106 };
 107
 108 #define MAX_F2FS_ERRORS                 16
 109
 110 struct f2fs_super_block {
 111         __le32 magic;                   /* Magic Number */
 112         __le16 major_ver;               /* Major Version */
 113         __le16 minor_ver;               /* Minor Version */
 114         __le32 log_sectorsize;          /* log2 sector size in bytes */
 115         __le32 log_sectors_per_block;   /* log2 # of sectors per block */
 116         __le32 log_blocksize;           /* log2 block size in bytes */
 117         __le32 log_blocks_per_seg;      /* log2 # of blocks per segment */
 118         __le32 segs_per_sec;            /* # of segments per section */
 119         __le32 secs_per_zone;           /* # of sections per zone */
 120         __le32 checksum_offset;         /* checksum offset inside super block */
 121         __le64 block_count;             /* total # of user blocks */
 122         __le32 section_count;           /* total # of sections */
 123         __le32 segment_count;           /* total # of segments */
 124         __le32 segment_count_ckpt;      /* # of segments for checkpoint */
 125         __le32 segment_count_sit;       /* # of segments for SIT */
 126         __le32 segment_count_nat;       /* # of segments for NAT */
 127         __le32 segment_count_ssa;       /* # of segments for SSA */
 128         __le32 segment_count_main;      /* # of segments for main area */
 129         __le32 segment0_blkaddr;        /* start block address of segment 0 */
 130         __le32 cp_blkaddr;              /* start block address of checkpoint */
 131         __le32 sit_blkaddr;             /* start block address of SIT */
 132         __le32 nat_blkaddr;             /* start block address of NAT */
 133         __le32 ssa_blkaddr;             /* start block address of SSA */
 134         __le32 main_blkaddr;            /* start block address of main area */
 135         __le32 root_ino;                /* root inode number */
 136         __le32 node_ino;                /* node inode number */
 137         __le32 meta_ino;                /* meta inode number */
 138         __u8 uuid[16];                  /* 128-bit uuid for volume */
 139         __le16 volume_name[MAX_VOLUME_NAME];    /* volume name */
 140         __le32 extension_count;         /* # of extensions below */
 141         __u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
 142         __le32 cp_payload;
 143         __u8 version[VERSION_LEN];      /* the kernel version */
 144         __u8 init_version[VERSION_LEN]; /* the initial kernel version */
 145         __le32 feature;                 /* defined features */
 146         __u8 encryption_level;          /* versioning level for encryption */
 147         __u8 encrypt_pw_salt[16];       /* Salt used for string2key algorithm */
 148         struct f2fs_device devs[MAX_DEVICES];   /* device list */
 149         __le32 qf_ino[F2FS_MAX_QUOTAS]; /* quota inode numbers */
 150         __u8 hot_ext_count;             /* # of hot file extension */
 151         __le16  s_encoding;             /* Filename charset encoding */
 152         __le16  s_encoding_flags;       /* Filename charset encoding flags */
 153         __u8 s_stop_reason[MAX_STOP_REASON];    /* stop checkpoint reason */
 154         __u8 s_errors[MAX_F2FS_ERRORS];         /* reason of image corrupts */
 155         __u8 reserved[258];             /* valid reserved region */
 156         __le32 crc;                     /* checksum of superblock */
 157 } __packed;
 158
 159 /*
 160  * For checkpoint
 161  */
 162 #define CP_RESIZEFS_FLAG                0x00004000
 163 #define CP_DISABLED_QUICK_FLAG          0x00002000
 164 #define CP_DISABLED_FLAG                0x00001000
 165 #define CP_QUOTA_NEED_FSCK_FLAG         0x00000800
 166 #define CP_LARGE_NAT_BITMAP_FLAG        0x00000400
 167 #define CP_NOCRC_RECOVERY_FLAG  0x00000200
 168 #define CP_TRIMMED_FLAG         0x00000100
 169 #define CP_NAT_BITS_FLAG        0x00000080
 170 #define CP_CRC_RECOVERY_FLAG    0x00000040
 171 #define CP_FASTBOOT_FLAG        0x00000020
 172 #define CP_FSCK_FLAG            0x00000010
 173 #define CP_ERROR_FLAG           0x00000008
 174 #define CP_COMPACT_SUM_FLAG     0x00000004
 175 #define CP_ORPHAN_PRESENT_FLAG  0x00000002
 176 #define CP_UMOUNT_FLAG          0x00000001
 177
 178 #define F2FS_CP_PACKS           2       /* # of checkpoint packs */
 179
 180 struct f2fs_checkpoint {
 181         __le64 checkpoint_ver;          /* checkpoint block version number */
 182         __le64 user_block_count;        /* # of user blocks */
 183         __le64 valid_block_count;       /* # of valid blocks in main area */
 184         __le32 rsvd_segment_count;      /* # of reserved segments for gc */
 185         __le32 overprov_segment_count;  /* # of overprovision segments */
 186         __le32 free_segment_count;      /* # of free segments in main area */
 187
 188         /* information of current node segments */
 189         __le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
 190         __le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
 191         /* information of current data segments */
 192         __le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
 193         __le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
 194         __le32 ckpt_flags;              /* Flags : umount and journal_present */
 195         __le32 cp_pack_total_block_count;       /* total # of one cp pack */
 196         __le32 cp_pack_start_sum;       /* start block number of data summary */
 197         __le32 valid_node_count;        /* Total number of valid nodes */
 198         __le32 valid_inode_count;       /* Total number of valid inodes */
 199         __le32 next_free_nid;           /* Next free node number */
 200         __le32 sit_ver_bitmap_bytesize; /* Default value 64 */
 201         __le32 nat_ver_bitmap_bytesize; /* Default value 256 */
 202         __le32 checksum_offset;         /* checksum offset inside cp block */
 203         __le64 elapsed_time;            /* mounted time */
 204         /* allocation type of current segment */
 205         unsigned char alloc_type[MAX_ACTIVE_LOGS];
 206
 207         /* SIT and NAT version bitmap */
 208         unsigned char sit_nat_version_bitmap[];
 209 } __packed;
 210
 211 #define CP_CHKSUM_OFFSET        (F2FS_BLKSIZE - sizeof(__le32)) /* default chksum offset in checkpoint */
 212 #define CP_MIN_CHKSUM_OFFSET                                            \
 213         (offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
 214
 215 /*
 216  * For orphan inode management
 217  */
 218 #define F2FS_ORPHANS_PER_BLOCK  ((F2FS_BLKSIZE - 4 * sizeof(__le32)) / sizeof(__le32))
 219
 220 #define GET_ORPHAN_BLOCKS(n)    (((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
 221                                         F2FS_ORPHANS_PER_BLOCK)
 222
 223 struct f2fs_orphan_block {
 224         __le32 ino[F2FS_ORPHANS_PER_BLOCK];     /* inode numbers */
 225         __le32 reserved;        /* reserved */
 226         __le16 blk_addr;        /* block index in current CP */
 227         __le16 blk_count;       /* Number of orphan inode blocks in CP */
 228         __le32 entry_count;     /* Total number of orphan nodes in current CP */
 229         __le32 check_sum;       /* CRC32 for orphan inode block */
 230 } __packed;
 231
 232 /*
 233  * For NODE structure
 234  */
 235 struct f2fs_extent {
 236         __le32 fofs;            /* start file offset of the extent */
 237         __le32 blk;             /* start block address of the extent */
 238         __le32 len;             /* length of the extent */
 239 } __packed;
 240
 241 #define F2FS_NAME_LEN           255
 242 /* 200 bytes for inline xattrs by default */
 243 #define DEFAULT_INLINE_XATTR_ADDRS      50
 244
 245 #define OFFSET_OF_END_OF_I_EXT          360
 246 #define SIZE_OF_I_NID                   20
 247
 248 struct node_footer {
 249         __le32 nid;             /* node id */
 250         __le32 ino;             /* inode number */
 251         __le32 flag;            /* include cold/fsync/dentry marks and offset */
 252         __le64 cp_ver;          /* checkpoint version */
 253         __le32 next_blkaddr;    /* next node page block address */
 254 } __packed;
 255
 256 /* Address Pointers in an Inode */
 257 #define DEF_ADDRS_PER_INODE     ((F2FS_BLKSIZE - OFFSET_OF_END_OF_I_EXT \
 258                                         - SIZE_OF_I_NID \
 259                                         - sizeof(struct node_footer)) / sizeof(__le32))
 260 #define CUR_ADDRS_PER_INODE(inode)      (DEF_ADDRS_PER_INODE - \
 261                                         get_extra_isize(inode))
 262 #define DEF_NIDS_PER_INODE      5       /* Node IDs in an Inode */
 263 #define ADDRS_PER_INODE(inode)  addrs_per_page(inode, true)
 264 /* Address Pointers in a Direct Block */
 265 #define DEF_ADDRS_PER_BLOCK     ((F2FS_BLKSIZE - sizeof(struct node_footer)) / sizeof(__le32))
 266 #define ADDRS_PER_BLOCK(inode)  addrs_per_page(inode, false)
 267 /* Node IDs in an Indirect Block */
 268 #define NIDS_PER_BLOCK          ((F2FS_BLKSIZE - sizeof(struct node_footer)) / sizeof(__le32))
 269
 270 #define ADDRS_PER_PAGE(page, inode)     (addrs_per_page(inode, IS_INODE(page)))
 271
 272 #define NODE_DIR1_BLOCK         (DEF_ADDRS_PER_INODE + 1)
 273 #define NODE_DIR2_BLOCK         (DEF_ADDRS_PER_INODE + 2)
 274 #define NODE_IND1_BLOCK         (DEF_ADDRS_PER_INODE + 3)
 275 #define NODE_IND2_BLOCK         (DEF_ADDRS_PER_INODE + 4)
 276 #define NODE_DIND_BLOCK         (DEF_ADDRS_PER_INODE + 5)
 277
 278 #define F2FS_INLINE_XATTR       0x01    /* file inline xattr flag */
 279 #define F2FS_INLINE_DATA        0x02    /* file inline data flag */
 280 #define F2FS_INLINE_DENTRY      0x04    /* file inline dentry flag */
 281 #define F2FS_DATA_EXIST         0x08    /* file inline data exist flag */
 282 #define F2FS_INLINE_DOTS        0x10    /* file having implicit dot dentries (obsolete) */
 283 #define F2FS_EXTRA_ATTR         0x20    /* file having extra attribute */
 284 #define F2FS_PIN_FILE           0x40    /* file should not be gced */
 285 #define F2FS_COMPRESS_RELEASED  0x80    /* file released compressed blocks */
 286
 287 struct f2fs_inode {
 288         __le16 i_mode;                  /* file mode */
 289         __u8 i_advise;                  /* file hints */
 290         __u8 i_inline;                  /* file inline flags */
 291         __le32 i_uid;                   /* user ID */
 292         __le32 i_gid;                   /* group ID */
 293         __le32 i_links;                 /* links count */
 294         __le64 i_size;                  /* file size in bytes */
 295         __le64 i_blocks;                /* file size in blocks */
 296         __le64 i_atime;                 /* access time */
 297         __le64 i_ctime;                 /* change time */
 298         __le64 i_mtime;                 /* modification time */
 299         __le32 i_atime_nsec;            /* access time in nano scale */
 300         __le32 i_ctime_nsec;            /* change time in nano scale */
 301         __le32 i_mtime_nsec;            /* modification time in nano scale */
 302         __le32 i_generation;            /* file version (for NFS) */
 303         union {
 304                 __le32 i_current_depth; /* only for directory depth */
 305                 __le16 i_gc_failures;   /*
 306                                          * # of gc failures on pinned file.
 307                                          * only for regular files.
 308                                          */
 309         };
 310         __le32 i_xattr_nid;             /* nid to save xattr */
 311         __le32 i_flags;                 /* file attributes */
 312         __le32 i_pino;                  /* parent inode number */
 313         __le32 i_namelen;               /* file name length */
 314         __u8 i_name[F2FS_NAME_LEN];     /* file name for SPOR */
 315         __u8 i_dir_level;               /* dentry_level for large dir */
 316
 317         struct f2fs_extent i_ext;       /* caching a largest extent */
 318
 319         union {
 320                 struct {
 321                         __le16 i_extra_isize;   /* extra inode attribute size */
 322                         __le16 i_inline_xattr_size;     /* inline xattr size, unit: 4 bytes */
 323                         __le32 i_projid;        /* project id */
 324                         __le32 i_inode_checksum;/* inode meta checksum */
 325                         __le64 i_crtime;        /* creation time */
 326                         __le32 i_crtime_nsec;   /* creation time in nano scale */
 327                         __le64 i_compr_blocks;  /* # of compressed blocks */
 328                         __u8 i_compress_algorithm;      /* compress algorithm */
 329                         __u8 i_log_cluster_size;        /* log of cluster size */
 330                         __le16 i_compress_flag;         /* compress flag */
 331                                                 /* 0 bit: chksum flag
 332                                                  * [8,15] bits: compress level
 333                                                  */
 334                         __le32 i_extra_end[0];  /* for attribute size calculation */
 335                 } __packed;
 336                 __le32 i_addr[DEF_ADDRS_PER_INODE];     /* Pointers to data blocks */
 337         };
 338         __le32 i_nid[DEF_NIDS_PER_INODE];       /* direct(2), indirect(2),
 339                                                 double_indirect(1) node id */
 340 } __packed;
 341
 342 struct direct_node {
 343         __le32 addr[DEF_ADDRS_PER_BLOCK];       /* array of data block address */
 344 } __packed;
 345
 346 struct indirect_node {
 347         __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 348 } __packed;
 349
 350 enum {
 351         COLD_BIT_SHIFT = 0,
 352         FSYNC_BIT_SHIFT,
 353         DENT_BIT_SHIFT,
 354         OFFSET_BIT_SHIFT
 355 };
 356
 357 #define OFFSET_BIT_MASK         GENMASK(OFFSET_BIT_SHIFT - 1, 0)
 358
 359 struct f2fs_node {
 360         /* can be one of three types: inode, direct, and indirect types */
 361         union {
 362                 struct f2fs_inode i;
 363                 struct direct_node dn;
 364                 struct indirect_node in;
 365         };
 366         struct node_footer footer;
 367 } __packed;
 368
 369 /*
 370  * For NAT entries
 371  */
 372 #define NAT_ENTRY_PER_BLOCK (F2FS_BLKSIZE / sizeof(struct f2fs_nat_entry))
 373
 374 struct f2fs_nat_entry {
 375         __u8 version;           /* latest version of cached nat entry */
 376         __le32 ino;             /* inode number */
 377         __le32 block_addr;      /* block address */
 378 } __packed;
 379
 380 struct f2fs_nat_block {
 381         struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
 382 } __packed;
 383
 384 /*
 385  * For SIT entries
 386  *
 387  * A validity bitmap of 64 bytes covers 512 blocks of area. For a 4K page size,
 388  * this results in a segment size of 2MB. For 16k pages, the default segment size
 389  * is 8MB.
 390  * Not allow to change this.
 391  */
 392 #define SIT_VBLOCK_MAP_SIZE 64
 393 #define SIT_ENTRY_PER_BLOCK (F2FS_BLKSIZE / sizeof(struct f2fs_sit_entry))
 394
 395 /*
 396  * F2FS uses 4 bytes to represent block address. As a result, supported size of
 397  * disk is 16 TB for a 4K page size and 64 TB for a 16K page size and it equals
 398  * to 16 * 1024 * 1024 / 2 segments.
 399  */
 400 #define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
 401
 402 /*
 403  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
 404  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
 405  * [9:0] : valid block count
 406  */
 407 #define SIT_VBLOCKS_SHIFT       10
 408 #define SIT_VBLOCKS_MASK        ((1 << SIT_VBLOCKS_SHIFT) - 1)
 409 #define GET_SIT_VBLOCKS(raw_sit)                                \
 410         (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
 411 #define GET_SIT_TYPE(raw_sit)                                   \
 412         ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)  \
 413          >> SIT_VBLOCKS_SHIFT)
 414
 415 struct f2fs_sit_entry {
 416         __le16 vblocks;                         /* reference above */
 417         __u8 valid_map[SIT_VBLOCK_MAP_SIZE];    /* bitmap for valid blocks */
 418         __le64 mtime;                           /* segment age for cleaning */
 419 } __packed;
 420
 421 struct f2fs_sit_block {
 422         struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
 423 } __packed;
 424
 425 /*
 426  * For segment summary
 427  *
 428  * One summary block with 4KB size contains exactly 512 summary entries, which
 429  * represents exactly one segment with 2MB size.
 430  * Similarly, in the case of block with 16KB size, it represents one segment with 8MB size.
 431  * Not allow to change the basic units.
 432  *
 433  * NOTE: For initializing fields, you must use set_summary
 434  *
 435  * - If data page, nid represents dnode's nid
 436  * - If node page, nid represents the node page's nid.
 437  *
 438  * The ofs_in_node is used by only data page. It represents offset
 439  * from node's page's beginning to get a data block address.
 440  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
 441  */
 442 #define ENTRIES_IN_SUM          (F2FS_BLKSIZE / 8)
 443 #define SUMMARY_SIZE            (7)     /* sizeof(struct f2fs_summary) */
 444 #define SUM_FOOTER_SIZE         (5)     /* sizeof(struct summary_footer) */
 445 #define SUM_ENTRY_SIZE          (SUMMARY_SIZE * ENTRIES_IN_SUM)
 446
 447 /* a summary entry for a block in a segment */
 448 struct f2fs_summary {
 449         __le32 nid;             /* parent node id */
 450         union {
 451                 __u8 reserved[3];
 452                 struct {
 453                         __u8 version;           /* node version number */
 454                         __le16 ofs_in_node;     /* block index in parent node */
 455                 } __packed;
 456         };
 457 } __packed;
 458
 459 /* summary block type, node or data, is stored to the summary_footer */
 460 #define SUM_TYPE_NODE           (1)
 461 #define SUM_TYPE_DATA           (0)
 462
 463 struct summary_footer {
 464         unsigned char entry_type;       /* SUM_TYPE_XXX */
 465         __le32 check_sum;               /* summary checksum */
 466 } __packed;
 467
 468 #define SUM_JOURNAL_SIZE        (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
 469                                 SUM_ENTRY_SIZE)
 470 #define NAT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 471                                 sizeof(struct nat_journal_entry))
 472 #define NAT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 473                                 sizeof(struct nat_journal_entry))
 474 #define SIT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 475                                 sizeof(struct sit_journal_entry))
 476 #define SIT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 477                                 sizeof(struct sit_journal_entry))
 478
 479 /* Reserved area should make size of f2fs_extra_info equals to
 480  * that of nat_journal and sit_journal.
 481  */
 482 #define EXTRA_INFO_RESERVED     (SUM_JOURNAL_SIZE - 2 - 8)
 483
 484 /*
 485  * frequently updated NAT/SIT entries can be stored in the spare area in
 486  * summary blocks
 487  */
 488 enum {
 489         NAT_JOURNAL = 0,
 490         SIT_JOURNAL
 491 };
 492
 493 struct nat_journal_entry {
 494         __le32 nid;
 495         struct f2fs_nat_entry ne;
 496 } __packed;
 497
 498 struct nat_journal {
 499         struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 500         __u8 reserved[NAT_JOURNAL_RESERVED];
 501 } __packed;
 502
 503 struct sit_journal_entry {
 504         __le32 segno;
 505         struct f2fs_sit_entry se;
 506 } __packed;
 507
 508 struct sit_journal {
 509         struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
 510         __u8 reserved[SIT_JOURNAL_RESERVED];
 511 } __packed;
 512
 513 struct f2fs_extra_info {
 514         __le64 kbytes_written;
 515         __u8 reserved[EXTRA_INFO_RESERVED];
 516 } __packed;
 517
 518 struct f2fs_journal {
 519         union {
 520                 __le16 n_nats;
 521                 __le16 n_sits;
 522         };
 523         /* spare area is used by NAT or SIT journals or extra info */
 524         union {
 525                 struct nat_journal nat_j;
 526                 struct sit_journal sit_j;
 527                 struct f2fs_extra_info info;
 528         };
 529 } __packed;
 530
 531 /* Block-sized summary block structure */
 532 struct f2fs_summary_block {
 533         struct f2fs_summary entries[ENTRIES_IN_SUM];
 534         struct f2fs_journal journal;
 535         struct summary_footer footer;
 536 } __packed;
 537
 538 /*
 539  * For directory operations
 540  */
 541 #define F2FS_DOT_HASH           0
 542 #define F2FS_DDOT_HASH          F2FS_DOT_HASH
 543 #define F2FS_MAX_HASH           (~((0x3ULL) << 62))
 544 #define F2FS_HASH_COL_BIT       ((0x1ULL) << 63)
 545
 546 typedef __le32  f2fs_hash_t;
 547
 548 /* One directory entry slot covers 8bytes-long file name */
 549 #define F2FS_SLOT_LEN           8
 550 #define F2FS_SLOT_LEN_BITS      3
 551
 552 #define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
 553
 554 /* MAX level for dir lookup */
 555 #define MAX_DIR_HASH_DEPTH      63
 556
 557 /* MAX buckets in one level of dir */
 558 #define MAX_DIR_BUCKETS         BIT((MAX_DIR_HASH_DEPTH / 2) - 1)
 559
 560 /*
 561  * space utilization of regular dentry and inline dentry (w/o extra reservation)
 562  * when block size is 4KB.
 563  *              regular dentry          inline dentry (def)     inline dentry (min)
 564  * bitmap       1 * 27 = 27             1 * 23 = 23             1 * 1 = 1
 565  * reserved     1 * 3 = 3               1 * 7 = 7               1 * 1 = 1
 566  * dentry       11 * 214 = 2354         11 * 182 = 2002         11 * 2 = 22
 567  * filename     8 * 214 = 1712          8 * 182 = 1456          8 * 2 = 16
 568  * total        4096                    3488                    40
 569  *
 570  * Note: there are more reserved space in inline dentry than in regular
 571  * dentry, when converting inline dentry we should handle this carefully.
 572  */
 573
 574 /* the number of dentry in a block */
 575 #define NR_DENTRY_IN_BLOCK      ((BITS_PER_BYTE * F2FS_BLKSIZE) / \
 576                                         ((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * BITS_PER_BYTE + 1))
 577 #define SIZE_OF_DIR_ENTRY       11      /* by byte */
 578 #define SIZE_OF_DENTRY_BITMAP   ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
 579                                         BITS_PER_BYTE)
 580 #define SIZE_OF_RESERVED        (F2FS_BLKSIZE - ((SIZE_OF_DIR_ENTRY + \
 581                                 F2FS_SLOT_LEN) * \
 582                                 NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
 583 #define MIN_INLINE_DENTRY_SIZE          40      /* just include '.' and '..' entries */
 584
 585 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
 586 struct f2fs_dir_entry {
 587         __le32 hash_code;       /* hash code of file name */
 588         __le32 ino;             /* inode number */
 589         __le16 name_len;        /* length of file name */
 590         __u8 file_type;         /* file type */
 591 } __packed;
 592
 593 /* Block-sized directory entry block */
 594 struct f2fs_dentry_block {
 595         /* validity bitmap for directory entries in each block */
 596         __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
 597         __u8 reserved[SIZE_OF_RESERVED];
 598         struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
 599         __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
 600 } __packed;
 601
 602 #define F2FS_DEF_PROJID         0       /* default project ID */
 603
 604 #endif  /* _LINUX_F2FS_FS_H */