LXR linux/include/linux/f2fs

   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        12      /* 12 bits for 4096 bytes */
  17#define F2FS_LOG_SECTORS_PER_BLOCK      3       /* log number for sector/blk */
  18#define F2FS_BLKSIZE                    4096    /* support only 4KB block */
  19#define F2FS_BLKSIZE_BITS               12      /* bits for F2FS_BLKSIZE */
  20#define F2FS_MAX_EXTENSION              64      /* # of extension entries */
  21#define F2FS_EXTENSION_LEN              8       /* max size of extension */
  22#define F2FS_BLK_ALIGN(x)       (((x) + F2FS_BLKSIZE - 1) >> F2FS_BLKSIZE_BITS)
  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#define COMPRESS_ADDR           ((block_t)-2)   /* used as compressed data flag */
  27
  28#define F2FS_BYTES_TO_BLK(bytes)        ((bytes) >> F2FS_BLKSIZE_BITS)
  29#define F2FS_BLK_TO_BYTES(blk)          ((blk) << F2FS_BLKSIZE_BITS)
  30
  31/* 0, 1(node nid), 2(meta nid) are reserved node id */
  32#define F2FS_RESERVED_NODE_NUM          3
  33
  34#define F2FS_ROOT_INO(sbi)      ((sbi)->root_ino_num)
  35#define F2FS_NODE_INO(sbi)      ((sbi)->node_ino_num)
  36#define F2FS_META_INO(sbi)      ((sbi)->meta_ino_num)
  37
  38#define F2FS_MAX_QUOTAS         3
  39
  40#define F2FS_ENC_UTF8_12_1      1
  41
  42#define F2FS_IO_SIZE(sbi)       (1 << F2FS_OPTION(sbi).write_io_size_bits) /* Blocks */
  43#define F2FS_IO_SIZE_KB(sbi)    (1 << (F2FS_OPTION(sbi).write_io_size_bits + 2)) /* KB */
  44#define F2FS_IO_SIZE_BYTES(sbi) (1 << (F2FS_OPTION(sbi).write_io_size_bits + 12)) /* B */
  45#define F2FS_IO_SIZE_BITS(sbi)  (F2FS_OPTION(sbi).write_io_size_bits) /* power of 2 */
  46#define F2FS_IO_SIZE_MASK(sbi)  (F2FS_IO_SIZE(sbi) - 1)
  47#define F2FS_IO_ALIGNED(sbi)    (F2FS_IO_SIZE(sbi) > 1)
  48
  49/* This flag is used by node and meta inodes, and by recovery */
  50#define GFP_F2FS_ZERO           (GFP_NOFS | __GFP_ZERO)
  51
  52/*
  53 * For further optimization on multi-head logs, on-disk layout supports maximum
  54 * 16 logs by default. The number, 16, is expected to cover all the cases
  55 * enoughly. The implementaion currently uses no more than 6 logs.
  56 * Half the logs are used for nodes, and the other half are used for data.
  57 */
  58#define MAX_ACTIVE_LOGS 16
  59#define MAX_ACTIVE_NODE_LOGS    8
  60#define MAX_ACTIVE_DATA_LOGS    8
  61
  62#define VERSION_LEN     256
  63#define MAX_VOLUME_NAME         512
  64#define MAX_PATH_LEN            64
  65#define MAX_DEVICES             8
  66
  67/*
  68 * For superblock
  69 */
  70struct f2fs_device {
  71        __u8 path[MAX_PATH_LEN];
  72        __le32 total_segments;
  73} __packed;
  74
  75struct f2fs_super_block {
  76        __le32 magic;                   /* Magic Number */
  77        __le16 major_ver;               /* Major Version */
  78        __le16 minor_ver;               /* Minor Version */
  79        __le32 log_sectorsize;          /* log2 sector size in bytes */
  80        __le32 log_sectors_per_block;   /* log2 # of sectors per block */
  81        __le32 log_blocksize;           /* log2 block size in bytes */
  82        __le32 log_blocks_per_seg;      /* log2 # of blocks per segment */
  83        __le32 segs_per_sec;            /* # of segments per section */
  84        __le32 secs_per_zone;           /* # of sections per zone */
  85        __le32 checksum_offset;         /* checksum offset inside super block */
  86        __le64 block_count;             /* total # of user blocks */
  87        __le32 section_count;           /* total # of sections */
  88        __le32 segment_count;           /* total # of segments */
  89        __le32 segment_count_ckpt;      /* # of segments for checkpoint */
  90        __le32 segment_count_sit;       /* # of segments for SIT */
  91        __le32 segment_count_nat;       /* # of segments for NAT */
  92        __le32 segment_count_ssa;       /* # of segments for SSA */
  93        __le32 segment_count_main;      /* # of segments for main area */
  94        __le32 segment0_blkaddr;        /* start block address of segment 0 */
  95        __le32 cp_blkaddr;              /* start block address of checkpoint */
  96        __le32 sit_blkaddr;             /* start block address of SIT */
  97        __le32 nat_blkaddr;             /* start block address of NAT */
  98        __le32 ssa_blkaddr;             /* start block address of SSA */
  99        __le32 main_blkaddr;            /* start block address of main area */
 100        __le32 root_ino;                /* root inode number */
 101        __le32 node_ino;                /* node inode number */
 102        __le32 meta_ino;                /* meta inode number */
 103        __u8 uuid[16];                  /* 128-bit uuid for volume */
 104        __le16 volume_name[MAX_VOLUME_NAME];    /* volume name */
 105        __le32 extension_count;         /* # of extensions below */
 106        __u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
 107        __le32 cp_payload;
 108        __u8 version[VERSION_LEN];      /* the kernel version */
 109        __u8 init_version[VERSION_LEN]; /* the initial kernel version */
 110        __le32 feature;                 /* defined features */
 111        __u8 encryption_level;          /* versioning level for encryption */
 112        __u8 encrypt_pw_salt[16];       /* Salt used for string2key algorithm */
 113        struct f2fs_device devs[MAX_DEVICES];   /* device list */
 114        __le32 qf_ino[F2FS_MAX_QUOTAS]; /* quota inode numbers */
 115        __u8 hot_ext_count;             /* # of hot file extension */
 116        __le16  s_encoding;             /* Filename charset encoding */
 117        __le16  s_encoding_flags;       /* Filename charset encoding flags */
 118        __u8 reserved[306];             /* valid reserved region */
 119        __le32 crc;                     /* checksum of superblock */
 120} __packed;
 121
 122/*
 123 * For checkpoint
 124 */
 125#define CP_RESIZEFS_FLAG                0x00004000
 126#define CP_DISABLED_QUICK_FLAG          0x00002000
 127#define CP_DISABLED_FLAG                0x00001000
 128#define CP_QUOTA_NEED_FSCK_FLAG         0x00000800
 129#define CP_LARGE_NAT_BITMAP_FLAG        0x00000400
 130#define CP_NOCRC_RECOVERY_FLAG  0x00000200
 131#define CP_TRIMMED_FLAG         0x00000100
 132#define CP_NAT_BITS_FLAG        0x00000080
 133#define CP_CRC_RECOVERY_FLAG    0x00000040
 134#define CP_FASTBOOT_FLAG        0x00000020
 135#define CP_FSCK_FLAG            0x00000010
 136#define CP_ERROR_FLAG           0x00000008
 137#define CP_COMPACT_SUM_FLAG     0x00000004
 138#define CP_ORPHAN_PRESENT_FLAG  0x00000002
 139#define CP_UMOUNT_FLAG          0x00000001
 140
 141#define F2FS_CP_PACKS           2       /* # of checkpoint packs */
 142
 143struct f2fs_checkpoint {
 144        __le64 checkpoint_ver;          /* checkpoint block version number */
 145        __le64 user_block_count;        /* # of user blocks */
 146        __le64 valid_block_count;       /* # of valid blocks in main area */
 147        __le32 rsvd_segment_count;      /* # of reserved segments for gc */
 148        __le32 overprov_segment_count;  /* # of overprovision segments */
 149        __le32 free_segment_count;      /* # of free segments in main area */
 150
 151        /* information of current node segments */
 152        __le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
 153        __le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
 154        /* information of current data segments */
 155        __le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
 156        __le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
 157        __le32 ckpt_flags;              /* Flags : umount and journal_present */
 158        __le32 cp_pack_total_block_count;       /* total # of one cp pack */
 159        __le32 cp_pack_start_sum;       /* start block number of data summary */
 160        __le32 valid_node_count;        /* Total number of valid nodes */
 161        __le32 valid_inode_count;       /* Total number of valid inodes */
 162        __le32 next_free_nid;           /* Next free node number */
 163        __le32 sit_ver_bitmap_bytesize; /* Default value 64 */
 164        __le32 nat_ver_bitmap_bytesize; /* Default value 256 */
 165        __le32 checksum_offset;         /* checksum offset inside cp block */
 166        __le64 elapsed_time;            /* mounted time */
 167        /* allocation type of current segment */
 168        unsigned char alloc_type[MAX_ACTIVE_LOGS];
 169
 170        /* SIT and NAT version bitmap */
 171        unsigned char sit_nat_version_bitmap[1];
 172} __packed;
 173
 174#define CP_CHKSUM_OFFSET        4092    /* default chksum offset in checkpoint */
 175#define CP_MIN_CHKSUM_OFFSET                                            \
 176        (offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
 177
 178/*
 179 * For orphan inode management
 180 */
 181#define F2FS_ORPHANS_PER_BLOCK  1020
 182
 183#define GET_ORPHAN_BLOCKS(n)    (((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
 184                                        F2FS_ORPHANS_PER_BLOCK)
 185
 186struct f2fs_orphan_block {
 187        __le32 ino[F2FS_ORPHANS_PER_BLOCK];     /* inode numbers */
 188        __le32 reserved;        /* reserved */
 189        __le16 blk_addr;        /* block index in current CP */
 190        __le16 blk_count;       /* Number of orphan inode blocks in CP */
 191        __le32 entry_count;     /* Total number of orphan nodes in current CP */
 192        __le32 check_sum;       /* CRC32 for orphan inode block */
 193} __packed;
 194
 195/*
 196 * For NODE structure
 197 */
 198struct f2fs_extent {
 199        __le32 fofs;            /* start file offset of the extent */
 200        __le32 blk;             /* start block address of the extent */
 201        __le32 len;             /* length of the extent */
 202} __packed;
 203
 204#define F2FS_NAME_LEN           255
 205/* 200 bytes for inline xattrs by default */
 206#define DEFAULT_INLINE_XATTR_ADDRS      50
 207#define DEF_ADDRS_PER_INODE     923     /* Address Pointers in an Inode */
 208#define CUR_ADDRS_PER_INODE(inode)      (DEF_ADDRS_PER_INODE - \
 209                                        get_extra_isize(inode))
 210#define DEF_NIDS_PER_INODE      5       /* Node IDs in an Inode */
 211#define ADDRS_PER_INODE(inode)  addrs_per_inode(inode)
 212#define DEF_ADDRS_PER_BLOCK     1018    /* Address Pointers in a Direct Block */
 213#define ADDRS_PER_BLOCK(inode)  addrs_per_block(inode)
 214#define NIDS_PER_BLOCK          1018    /* Node IDs in an Indirect Block */
 215
 216#define ADDRS_PER_PAGE(page, inode)     \
 217        (IS_INODE(page) ? ADDRS_PER_INODE(inode) : ADDRS_PER_BLOCK(inode))
 218
 219#define NODE_DIR1_BLOCK         (DEF_ADDRS_PER_INODE + 1)
 220#define NODE_DIR2_BLOCK         (DEF_ADDRS_PER_INODE + 2)
 221#define NODE_IND1_BLOCK         (DEF_ADDRS_PER_INODE + 3)
 222#define NODE_IND2_BLOCK         (DEF_ADDRS_PER_INODE + 4)
 223#define NODE_DIND_BLOCK         (DEF_ADDRS_PER_INODE + 5)
 224
 225#define F2FS_INLINE_XATTR       0x01    /* file inline xattr flag */
 226#define F2FS_INLINE_DATA        0x02    /* file inline data flag */
 227#define F2FS_INLINE_DENTRY      0x04    /* file inline dentry flag */
 228#define F2FS_DATA_EXIST         0x08    /* file inline data exist flag */
 229#define F2FS_INLINE_DOTS        0x10    /* file having implicit dot dentries */
 230#define F2FS_EXTRA_ATTR         0x20    /* file having extra attribute */
 231#define F2FS_PIN_FILE           0x40    /* file should not be gced */
 232
 233struct f2fs_inode {
 234        __le16 i_mode;                  /* file mode */
 235        __u8 i_advise;                  /* file hints */
 236        __u8 i_inline;                  /* file inline flags */
 237        __le32 i_uid;                   /* user ID */
 238        __le32 i_gid;                   /* group ID */
 239        __le32 i_links;                 /* links count */
 240        __le64 i_size;                  /* file size in bytes */
 241        __le64 i_blocks;                /* file size in blocks */
 242        __le64 i_atime;                 /* access time */
 243        __le64 i_ctime;                 /* change time */
 244        __le64 i_mtime;                 /* modification time */
 245        __le32 i_atime_nsec;            /* access time in nano scale */
 246        __le32 i_ctime_nsec;            /* change time in nano scale */
 247        __le32 i_mtime_nsec;            /* modification time in nano scale */
 248        __le32 i_generation;            /* file version (for NFS) */
 249        union {
 250                __le32 i_current_depth; /* only for directory depth */
 251                __le16 i_gc_failures;   /*
 252                                         * # of gc failures on pinned file.
 253                                         * only for regular files.
 254                                         */
 255        };
 256        __le32 i_xattr_nid;             /* nid to save xattr */
 257        __le32 i_flags;                 /* file attributes */
 258        __le32 i_pino;                  /* parent inode number */
 259        __le32 i_namelen;               /* file name length */
 260        __u8 i_name[F2FS_NAME_LEN];     /* file name for SPOR */
 261        __u8 i_dir_level;               /* dentry_level for large dir */
 262
 263        struct f2fs_extent i_ext;       /* caching a largest extent */
 264
 265        union {
 266                struct {
 267                        __le16 i_extra_isize;   /* extra inode attribute size */
 268                        __le16 i_inline_xattr_size;     /* inline xattr size, unit: 4 bytes */
 269                        __le32 i_projid;        /* project id */
 270                        __le32 i_inode_checksum;/* inode meta checksum */
 271                        __le64 i_crtime;        /* creation time */
 272                        __le32 i_crtime_nsec;   /* creation time in nano scale */
 273                        __le64 i_compr_blocks;  /* # of compressed blocks */
 274                        __u8 i_compress_algorithm;      /* compress algorithm */
 275                        __u8 i_log_cluster_size;        /* log of cluster size */
 276                        __le16 i_padding;               /* padding */
 277                        __le32 i_extra_end[0];  /* for attribute size calculation */
 278                } __packed;
 279                __le32 i_addr[DEF_ADDRS_PER_INODE];     /* Pointers to data blocks */
 280        };
 281        __le32 i_nid[DEF_NIDS_PER_INODE];       /* direct(2), indirect(2),
 282                                                double_indirect(1) node id */
 283} __packed;
 284
 285struct direct_node {
 286        __le32 addr[DEF_ADDRS_PER_BLOCK];       /* array of data block address */
 287} __packed;
 288
 289struct indirect_node {
 290        __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 291} __packed;
 292
 293enum {
 294        COLD_BIT_SHIFT = 0,
 295        FSYNC_BIT_SHIFT,
 296        DENT_BIT_SHIFT,
 297        OFFSET_BIT_SHIFT
 298};
 299
 300#define OFFSET_BIT_MASK         (0x07)  /* (0x01 << OFFSET_BIT_SHIFT) - 1 */
 301
 302struct node_footer {
 303        __le32 nid;             /* node id */
 304        __le32 ino;             /* inode number */
 305        __le32 flag;            /* include cold/fsync/dentry marks and offset */
 306        __le64 cp_ver;          /* checkpoint version */
 307        __le32 next_blkaddr;    /* next node page block address */
 308} __packed;
 309
 310struct f2fs_node {
 311        /* can be one of three types: inode, direct, and indirect types */
 312        union {
 313                struct f2fs_inode i;
 314                struct direct_node dn;
 315                struct indirect_node in;
 316        };
 317        struct node_footer footer;
 318} __packed;
 319
 320/*
 321 * For NAT entries
 322 */
 323#define NAT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_nat_entry))
 324
 325struct f2fs_nat_entry {
 326        __u8 version;           /* latest version of cached nat entry */
 327        __le32 ino;             /* inode number */
 328        __le32 block_addr;      /* block address */
 329} __packed;
 330
 331struct f2fs_nat_block {
 332        struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
 333} __packed;
 334
 335/*
 336 * For SIT entries
 337 *
 338 * Each segment is 2MB in size by default so that a bitmap for validity of
 339 * there-in blocks should occupy 64 bytes, 512 bits.
 340 * Not allow to change this.
 341 */
 342#define SIT_VBLOCK_MAP_SIZE 64
 343#define SIT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_sit_entry))
 344
 345/*
 346 * F2FS uses 4 bytes to represent block address. As a result, supported size of
 347 * disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
 348 */
 349#define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
 350
 351/*
 352 * Note that f2fs_sit_entry->vblocks has the following bit-field information.
 353 * [15:10] : allocation type such as CURSEG_XXXX_TYPE
 354 * [9:0] : valid block count
 355 */
 356#define SIT_VBLOCKS_SHIFT       10
 357#define SIT_VBLOCKS_MASK        ((1 << SIT_VBLOCKS_SHIFT) - 1)
 358#define GET_SIT_VBLOCKS(raw_sit)                                \
 359        (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
 360#define GET_SIT_TYPE(raw_sit)                                   \
 361        ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)  \
 362         >> SIT_VBLOCKS_SHIFT)
 363
 364struct f2fs_sit_entry {
 365        __le16 vblocks;                         /* reference above */
 366        __u8 valid_map[SIT_VBLOCK_MAP_SIZE];    /* bitmap for valid blocks */
 367        __le64 mtime;                           /* segment age for cleaning */
 368} __packed;
 369
 370struct f2fs_sit_block {
 371        struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
 372} __packed;
 373
 374/*
 375 * For segment summary
 376 *
 377 * One summary block contains exactly 512 summary entries, which represents
 378 * exactly 2MB segment by default. Not allow to change the basic units.
 379 *
 380 * NOTE: For initializing fields, you must use set_summary
 381 *
 382 * - If data page, nid represents dnode's nid
 383 * - If node page, nid represents the node page's nid.
 384 *
 385 * The ofs_in_node is used by only data page. It represents offset
 386 * from node's page's beginning to get a data block address.
 387 * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
 388 */
 389#define ENTRIES_IN_SUM          512
 390#define SUMMARY_SIZE            (7)     /* sizeof(struct summary) */
 391#define SUM_FOOTER_SIZE         (5)     /* sizeof(struct summary_footer) */
 392#define SUM_ENTRY_SIZE          (SUMMARY_SIZE * ENTRIES_IN_SUM)
 393
 394/* a summary entry for a 4KB-sized block in a segment */
 395struct f2fs_summary {
 396        __le32 nid;             /* parent node id */
 397        union {
 398                __u8 reserved[3];
 399                struct {
 400                        __u8 version;           /* node version number */
 401                        __le16 ofs_in_node;     /* block index in parent node */
 402                } __packed;
 403        };
 404} __packed;
 405
 406/* summary block type, node or data, is stored to the summary_footer */
 407#define SUM_TYPE_NODE           (1)
 408#define SUM_TYPE_DATA           (0)
 409
 410struct summary_footer {
 411        unsigned char entry_type;       /* SUM_TYPE_XXX */
 412        __le32 check_sum;               /* summary checksum */
 413} __packed;
 414
 415#define SUM_JOURNAL_SIZE        (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
 416                                SUM_ENTRY_SIZE)
 417#define NAT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 418                                sizeof(struct nat_journal_entry))
 419#define NAT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 420                                sizeof(struct nat_journal_entry))
 421#define SIT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 422                                sizeof(struct sit_journal_entry))
 423#define SIT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 424                                sizeof(struct sit_journal_entry))
 425
 426/* Reserved area should make size of f2fs_extra_info equals to
 427 * that of nat_journal and sit_journal.
 428 */
 429#define EXTRA_INFO_RESERVED     (SUM_JOURNAL_SIZE - 2 - 8)
 430
 431/*
 432 * frequently updated NAT/SIT entries can be stored in the spare area in
 433 * summary blocks
 434 */
 435enum {
 436        NAT_JOURNAL = 0,
 437        SIT_JOURNAL
 438};
 439
 440struct nat_journal_entry {
 441        __le32 nid;
 442        struct f2fs_nat_entry ne;
 443} __packed;
 444
 445struct nat_journal {
 446        struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 447        __u8 reserved[NAT_JOURNAL_RESERVED];
 448} __packed;
 449
 450struct sit_journal_entry {
 451        __le32 segno;
 452        struct f2fs_sit_entry se;
 453} __packed;
 454
 455struct sit_journal {
 456        struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
 457        __u8 reserved[SIT_JOURNAL_RESERVED];
 458} __packed;
 459
 460struct f2fs_extra_info {
 461        __le64 kbytes_written;
 462        __u8 reserved[EXTRA_INFO_RESERVED];
 463} __packed;
 464
 465struct f2fs_journal {
 466        union {
 467                __le16 n_nats;
 468                __le16 n_sits;
 469        };
 470        /* spare area is used by NAT or SIT journals or extra info */
 471        union {
 472                struct nat_journal nat_j;
 473                struct sit_journal sit_j;
 474                struct f2fs_extra_info info;
 475        };
 476} __packed;
 477
 478/* 4KB-sized summary block structure */
 479struct f2fs_summary_block {
 480        struct f2fs_summary entries[ENTRIES_IN_SUM];
 481        struct f2fs_journal journal;
 482        struct summary_footer footer;
 483} __packed;
 484
 485/*
 486 * For directory operations
 487 */
 488#define F2FS_DOT_HASH           0
 489#define F2FS_DDOT_HASH          F2FS_DOT_HASH
 490#define F2FS_MAX_HASH           (~((0x3ULL) << 62))
 491#define F2FS_HASH_COL_BIT       ((0x1ULL) << 63)
 492
 493typedef __le32  f2fs_hash_t;
 494
 495/* One directory entry slot covers 8bytes-long file name */
 496#define F2FS_SLOT_LEN           8
 497#define F2FS_SLOT_LEN_BITS      3
 498
 499#define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
 500
 501/* MAX level for dir lookup */
 502#define MAX_DIR_HASH_DEPTH      63
 503
 504/* MAX buckets in one level of dir */
 505#define MAX_DIR_BUCKETS         (1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
 506
 507/*
 508 * space utilization of regular dentry and inline dentry (w/o extra reservation)
 509 *              regular dentry          inline dentry (def)     inline dentry (min)
 510 * bitmap       1 * 27 = 27             1 * 23 = 23             1 * 1 = 1
 511 * reserved     1 * 3 = 3               1 * 7 = 7               1 * 1 = 1
 512 * dentry       11 * 214 = 2354         11 * 182 = 2002         11 * 2 = 22
 513 * filename     8 * 214 = 1712          8 * 182 = 1456          8 * 2 = 16
 514 * total        4096                    3488                    40
 515 *
 516 * Note: there are more reserved space in inline dentry than in regular
 517 * dentry, when converting inline dentry we should handle this carefully.
 518 */
 519#define NR_DENTRY_IN_BLOCK      214     /* the number of dentry in a block */
 520#define SIZE_OF_DIR_ENTRY       11      /* by byte */
 521#define SIZE_OF_DENTRY_BITMAP   ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
 522                                        BITS_PER_BYTE)
 523#define SIZE_OF_RESERVED        (PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
 524                                F2FS_SLOT_LEN) * \
 525                                NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
 526#define MIN_INLINE_DENTRY_SIZE          40      /* just include '.' and '..' entries */
 527
 528/* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
 529struct f2fs_dir_entry {
 530        __le32 hash_code;       /* hash code of file name */
 531        __le32 ino;             /* inode number */
 532        __le16 name_len;        /* length of file name */
 533        __u8 file_type;         /* file type */
 534} __packed;
 535
 536/* 4KB-sized directory entry block */
 537struct f2fs_dentry_block {
 538        /* validity bitmap for directory entries in each block */
 539        __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
 540        __u8 reserved[SIZE_OF_RESERVED];
 541        struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
 542        __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
 543} __packed;
 544
 545/* file types used in inode_info->flags */
 546enum {
 547        F2FS_FT_UNKNOWN,
 548        F2FS_FT_REG_FILE,
 549        F2FS_FT_DIR,
 550        F2FS_FT_CHRDEV,
 551        F2FS_FT_BLKDEV,
 552        F2FS_FT_FIFO,
 553        F2FS_FT_SOCK,
 554        F2FS_FT_SYMLINK,
 555        F2FS_FT_MAX
 556};
 557
 558#define S_SHIFT 12
 559
 560#define F2FS_DEF_PROJID         0       /* default project ID */
 561
 562#endif  /* _LINUX_F2FS_FS_H */
 563