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#define F2FS_ENC_STRICT_MODE_FL (1 << 0)
  42#define f2fs_has_strict_mode(sbi) \
  43        (sbi->s_encoding_flags & F2FS_ENC_STRICT_MODE_FL)
  44
  45#define F2FS_IO_SIZE(sbi)       (1 << F2FS_OPTION(sbi).write_io_size_bits) /* Blocks */
  46#define F2FS_IO_SIZE_KB(sbi)    (1 << (F2FS_OPTION(sbi).write_io_size_bits + 2)) /* KB */
  47#define F2FS_IO_SIZE_BYTES(sbi) (1 << (F2FS_OPTION(sbi).write_io_size_bits + 12)) /* B */
  48#define F2FS_IO_SIZE_BITS(sbi)  (F2FS_OPTION(sbi).write_io_size_bits) /* power of 2 */
  49#define F2FS_IO_SIZE_MASK(sbi)  (F2FS_IO_SIZE(sbi) - 1)
  50#define F2FS_IO_ALIGNED(sbi)    (F2FS_IO_SIZE(sbi) > 1)
  51
  52/* This flag is used by node and meta inodes, and by recovery */
  53#define GFP_F2FS_ZERO           (GFP_NOFS | __GFP_ZERO)
  54
  55/*
  56 * For further optimization on multi-head logs, on-disk layout supports maximum
  57 * 16 logs by default. The number, 16, is expected to cover all the cases
  58 * enoughly. The implementaion currently uses no more than 6 logs.
  59 * Half the logs are used for nodes, and the other half are used for data.
  60 */
  61#define MAX_ACTIVE_LOGS 16
  62#define MAX_ACTIVE_NODE_LOGS    8
  63#define MAX_ACTIVE_DATA_LOGS    8
  64
  65#define VERSION_LEN     256
  66#define MAX_VOLUME_NAME         512
  67#define MAX_PATH_LEN            64
  68#define MAX_DEVICES             8
  69
  70/*
  71 * For superblock
  72 */
  73struct f2fs_device {
  74        __u8 path[MAX_PATH_LEN];
  75        __le32 total_segments;
  76} __packed;
  77
  78struct f2fs_super_block {
  79        __le32 magic;                   /* Magic Number */
  80        __le16 major_ver;               /* Major Version */
  81        __le16 minor_ver;               /* Minor Version */
  82        __le32 log_sectorsize;          /* log2 sector size in bytes */
  83        __le32 log_sectors_per_block;   /* log2 # of sectors per block */
  84        __le32 log_blocksize;           /* log2 block size in bytes */
  85        __le32 log_blocks_per_seg;      /* log2 # of blocks per segment */
  86        __le32 segs_per_sec;            /* # of segments per section */
  87        __le32 secs_per_zone;           /* # of sections per zone */
  88        __le32 checksum_offset;         /* checksum offset inside super block */
  89        __le64 block_count;             /* total # of user blocks */
  90        __le32 section_count;           /* total # of sections */
  91        __le32 segment_count;           /* total # of segments */
  92        __le32 segment_count_ckpt;      /* # of segments for checkpoint */
  93        __le32 segment_count_sit;       /* # of segments for SIT */
  94        __le32 segment_count_nat;       /* # of segments for NAT */
  95        __le32 segment_count_ssa;       /* # of segments for SSA */
  96        __le32 segment_count_main;      /* # of segments for main area */
  97        __le32 segment0_blkaddr;        /* start block address of segment 0 */
  98        __le32 cp_blkaddr;              /* start block address of checkpoint */
  99        __le32 sit_blkaddr;             /* start block address of SIT */
 100        __le32 nat_blkaddr;             /* start block address of NAT */
 101        __le32 ssa_blkaddr;             /* start block address of SSA */
 102        __le32 main_blkaddr;            /* start block address of main area */
 103        __le32 root_ino;                /* root inode number */
 104        __le32 node_ino;                /* node inode number */
 105        __le32 meta_ino;                /* meta inode number */
 106        __u8 uuid[16];                  /* 128-bit uuid for volume */
 107        __le16 volume_name[MAX_VOLUME_NAME];    /* volume name */
 108        __le32 extension_count;         /* # of extensions below */
 109        __u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
 110        __le32 cp_payload;
 111        __u8 version[VERSION_LEN];      /* the kernel version */
 112        __u8 init_version[VERSION_LEN]; /* the initial kernel version */
 113        __le32 feature;                 /* defined features */
 114        __u8 encryption_level;          /* versioning level for encryption */
 115        __u8 encrypt_pw_salt[16];       /* Salt used for string2key algorithm */
 116        struct f2fs_device devs[MAX_DEVICES];   /* device list */
 117        __le32 qf_ino[F2FS_MAX_QUOTAS]; /* quota inode numbers */
 118        __u8 hot_ext_count;             /* # of hot file extension */
 119        __le16  s_encoding;             /* Filename charset encoding */
 120        __le16  s_encoding_flags;       /* Filename charset encoding flags */
 121        __u8 reserved[306];             /* valid reserved region */
 122        __le32 crc;                     /* checksum of superblock */
 123} __packed;
 124
 125/*
 126 * For checkpoint
 127 */
 128#define CP_RESIZEFS_FLAG                0x00004000
 129#define CP_DISABLED_QUICK_FLAG          0x00002000
 130#define CP_DISABLED_FLAG                0x00001000
 131#define CP_QUOTA_NEED_FSCK_FLAG         0x00000800
 132#define CP_LARGE_NAT_BITMAP_FLAG        0x00000400
 133#define CP_NOCRC_RECOVERY_FLAG  0x00000200
 134#define CP_TRIMMED_FLAG         0x00000100
 135#define CP_NAT_BITS_FLAG        0x00000080
 136#define CP_CRC_RECOVERY_FLAG    0x00000040
 137#define CP_FASTBOOT_FLAG        0x00000020
 138#define CP_FSCK_FLAG            0x00000010
 139#define CP_ERROR_FLAG           0x00000008
 140#define CP_COMPACT_SUM_FLAG     0x00000004
 141#define CP_ORPHAN_PRESENT_FLAG  0x00000002
 142#define CP_UMOUNT_FLAG          0x00000001
 143
 144#define F2FS_CP_PACKS           2       /* # of checkpoint packs */
 145
 146struct f2fs_checkpoint {
 147        __le64 checkpoint_ver;          /* checkpoint block version number */
 148        __le64 user_block_count;        /* # of user blocks */
 149        __le64 valid_block_count;       /* # of valid blocks in main area */
 150        __le32 rsvd_segment_count;      /* # of reserved segments for gc */
 151        __le32 overprov_segment_count;  /* # of overprovision segments */
 152        __le32 free_segment_count;      /* # of free segments in main area */
 153
 154        /* information of current node segments */
 155        __le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
 156        __le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
 157        /* information of current data segments */
 158        __le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
 159        __le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
 160        __le32 ckpt_flags;              /* Flags : umount and journal_present */
 161        __le32 cp_pack_total_block_count;       /* total # of one cp pack */
 162        __le32 cp_pack_start_sum;       /* start block number of data summary */
 163        __le32 valid_node_count;        /* Total number of valid nodes */
 164        __le32 valid_inode_count;       /* Total number of valid inodes */
 165        __le32 next_free_nid;           /* Next free node number */
 166        __le32 sit_ver_bitmap_bytesize; /* Default value 64 */
 167        __le32 nat_ver_bitmap_bytesize; /* Default value 256 */
 168        __le32 checksum_offset;         /* checksum offset inside cp block */
 169        __le64 elapsed_time;            /* mounted time */
 170        /* allocation type of current segment */
 171        unsigned char alloc_type[MAX_ACTIVE_LOGS];
 172
 173        /* SIT and NAT version bitmap */
 174        unsigned char sit_nat_version_bitmap[1];
 175} __packed;
 176
 177#define CP_CHKSUM_OFFSET        4092    /* default chksum offset in checkpoint */
 178#define CP_MIN_CHKSUM_OFFSET                                            \
 179        (offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
 180
 181/*
 182 * For orphan inode management
 183 */
 184#define F2FS_ORPHANS_PER_BLOCK  1020
 185
 186#define GET_ORPHAN_BLOCKS(n)    (((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
 187                                        F2FS_ORPHANS_PER_BLOCK)
 188
 189struct f2fs_orphan_block {
 190        __le32 ino[F2FS_ORPHANS_PER_BLOCK];     /* inode numbers */
 191        __le32 reserved;        /* reserved */
 192        __le16 blk_addr;        /* block index in current CP */
 193        __le16 blk_count;       /* Number of orphan inode blocks in CP */
 194        __le32 entry_count;     /* Total number of orphan nodes in current CP */
 195        __le32 check_sum;       /* CRC32 for orphan inode block */
 196} __packed;
 197
 198/*
 199 * For NODE structure
 200 */
 201struct f2fs_extent {
 202        __le32 fofs;            /* start file offset of the extent */
 203        __le32 blk;             /* start block address of the extent */
 204        __le32 len;             /* length of the extent */
 205} __packed;
 206
 207#define F2FS_NAME_LEN           255
 208/* 200 bytes for inline xattrs by default */
 209#define DEFAULT_INLINE_XATTR_ADDRS      50
 210#define DEF_ADDRS_PER_INODE     923     /* Address Pointers in an Inode */
 211#define CUR_ADDRS_PER_INODE(inode)      (DEF_ADDRS_PER_INODE - \
 212                                        get_extra_isize(inode))
 213#define DEF_NIDS_PER_INODE      5       /* Node IDs in an Inode */
 214#define ADDRS_PER_INODE(inode)  addrs_per_inode(inode)
 215#define DEF_ADDRS_PER_BLOCK     1018    /* Address Pointers in a Direct Block */
 216#define ADDRS_PER_BLOCK(inode)  addrs_per_block(inode)
 217#define NIDS_PER_BLOCK          1018    /* Node IDs in an Indirect Block */
 218
 219#define ADDRS_PER_PAGE(page, inode)     \
 220        (IS_INODE(page) ? ADDRS_PER_INODE(inode) : ADDRS_PER_BLOCK(inode))
 221
 222#define NODE_DIR1_BLOCK         (DEF_ADDRS_PER_INODE + 1)
 223#define NODE_DIR2_BLOCK         (DEF_ADDRS_PER_INODE + 2)
 224#define NODE_IND1_BLOCK         (DEF_ADDRS_PER_INODE + 3)
 225#define NODE_IND2_BLOCK         (DEF_ADDRS_PER_INODE + 4)
 226#define NODE_DIND_BLOCK         (DEF_ADDRS_PER_INODE + 5)
 227
 228#define F2FS_INLINE_XATTR       0x01    /* file inline xattr flag */
 229#define F2FS_INLINE_DATA        0x02    /* file inline data flag */
 230#define F2FS_INLINE_DENTRY      0x04    /* file inline dentry flag */
 231#define F2FS_DATA_EXIST         0x08    /* file inline data exist flag */
 232#define F2FS_INLINE_DOTS        0x10    /* file having implicit dot dentries */
 233#define F2FS_EXTRA_ATTR         0x20    /* file having extra attribute */
 234#define F2FS_PIN_FILE           0x40    /* file should not be gced */
 235
 236struct f2fs_inode {
 237        __le16 i_mode;                  /* file mode */
 238        __u8 i_advise;                  /* file hints */
 239        __u8 i_inline;                  /* file inline flags */
 240        __le32 i_uid;                   /* user ID */
 241        __le32 i_gid;                   /* group ID */
 242        __le32 i_links;                 /* links count */
 243        __le64 i_size;                  /* file size in bytes */
 244        __le64 i_blocks;                /* file size in blocks */
 245        __le64 i_atime;                 /* access time */
 246        __le64 i_ctime;                 /* change time */
 247        __le64 i_mtime;                 /* modification time */
 248        __le32 i_atime_nsec;            /* access time in nano scale */
 249        __le32 i_ctime_nsec;            /* change time in nano scale */
 250        __le32 i_mtime_nsec;            /* modification time in nano scale */
 251        __le32 i_generation;            /* file version (for NFS) */
 252        union {
 253                __le32 i_current_depth; /* only for directory depth */
 254                __le16 i_gc_failures;   /*
 255                                         * # of gc failures on pinned file.
 256                                         * only for regular files.
 257                                         */
 258        };
 259        __le32 i_xattr_nid;             /* nid to save xattr */
 260        __le32 i_flags;                 /* file attributes */
 261        __le32 i_pino;                  /* parent inode number */
 262        __le32 i_namelen;               /* file name length */
 263        __u8 i_name[F2FS_NAME_LEN];     /* file name for SPOR */
 264        __u8 i_dir_level;               /* dentry_level for large dir */
 265
 266        struct f2fs_extent i_ext;       /* caching a largest extent */
 267
 268        union {
 269                struct {
 270                        __le16 i_extra_isize;   /* extra inode attribute size */
 271                        __le16 i_inline_xattr_size;     /* inline xattr size, unit: 4 bytes */
 272                        __le32 i_projid;        /* project id */
 273                        __le32 i_inode_checksum;/* inode meta checksum */
 274                        __le64 i_crtime;        /* creation time */
 275                        __le32 i_crtime_nsec;   /* creation time in nano scale */
 276                        __le64 i_compr_blocks;  /* # of compressed blocks */
 277                        __u8 i_compress_algorithm;      /* compress algorithm */
 278                        __u8 i_log_cluster_size;        /* log of cluster size */
 279                        __le16 i_padding;               /* padding */
 280                        __le32 i_extra_end[0];  /* for attribute size calculation */
 281                } __packed;
 282                __le32 i_addr[DEF_ADDRS_PER_INODE];     /* Pointers to data blocks */
 283        };
 284        __le32 i_nid[DEF_NIDS_PER_INODE];       /* direct(2), indirect(2),
 285                                                double_indirect(1) node id */
 286} __packed;
 287
 288struct direct_node {
 289        __le32 addr[DEF_ADDRS_PER_BLOCK];       /* array of data block address */
 290} __packed;
 291
 292struct indirect_node {
 293        __le32 nid[NIDS_PER_BLOCK];     /* array of data block address */
 294} __packed;
 295
 296enum {
 297        COLD_BIT_SHIFT = 0,
 298        FSYNC_BIT_SHIFT,
 299        DENT_BIT_SHIFT,
 300        OFFSET_BIT_SHIFT
 301};
 302
 303#define OFFSET_BIT_MASK         (0x07)  /* (0x01 << OFFSET_BIT_SHIFT) - 1 */
 304
 305struct node_footer {
 306        __le32 nid;             /* node id */
 307        __le32 ino;             /* inode number */
 308        __le32 flag;            /* include cold/fsync/dentry marks and offset */
 309        __le64 cp_ver;          /* checkpoint version */
 310        __le32 next_blkaddr;    /* next node page block address */
 311} __packed;
 312
 313struct f2fs_node {
 314        /* can be one of three types: inode, direct, and indirect types */
 315        union {
 316                struct f2fs_inode i;
 317                struct direct_node dn;
 318                struct indirect_node in;
 319        };
 320        struct node_footer footer;
 321} __packed;
 322
 323/*
 324 * For NAT entries
 325 */
 326#define NAT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_nat_entry))
 327
 328struct f2fs_nat_entry {
 329        __u8 version;           /* latest version of cached nat entry */
 330        __le32 ino;             /* inode number */
 331        __le32 block_addr;      /* block address */
 332} __packed;
 333
 334struct f2fs_nat_block {
 335        struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
 336} __packed;
 337
 338/*
 339 * For SIT entries
 340 *
 341 * Each segment is 2MB in size by default so that a bitmap for validity of
 342 * there-in blocks should occupy 64 bytes, 512 bits.
 343 * Not allow to change this.
 344 */
 345#define SIT_VBLOCK_MAP_SIZE 64
 346#define SIT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_sit_entry))
 347
 348/*
 349 * F2FS uses 4 bytes to represent block address. As a result, supported size of
 350 * disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
 351 */
 352#define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
 353
 354/*
 355 * Note that f2fs_sit_entry->vblocks has the following bit-field information.
 356 * [15:10] : allocation type such as CURSEG_XXXX_TYPE
 357 * [9:0] : valid block count
 358 */
 359#define SIT_VBLOCKS_SHIFT       10
 360#define SIT_VBLOCKS_MASK        ((1 << SIT_VBLOCKS_SHIFT) - 1)
 361#define GET_SIT_VBLOCKS(raw_sit)                                \
 362        (le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
 363#define GET_SIT_TYPE(raw_sit)                                   \
 364        ((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)  \
 365         >> SIT_VBLOCKS_SHIFT)
 366
 367struct f2fs_sit_entry {
 368        __le16 vblocks;                         /* reference above */
 369        __u8 valid_map[SIT_VBLOCK_MAP_SIZE];    /* bitmap for valid blocks */
 370        __le64 mtime;                           /* segment age for cleaning */
 371} __packed;
 372
 373struct f2fs_sit_block {
 374        struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
 375} __packed;
 376
 377/*
 378 * For segment summary
 379 *
 380 * One summary block contains exactly 512 summary entries, which represents
 381 * exactly 2MB segment by default. Not allow to change the basic units.
 382 *
 383 * NOTE: For initializing fields, you must use set_summary
 384 *
 385 * - If data page, nid represents dnode's nid
 386 * - If node page, nid represents the node page's nid.
 387 *
 388 * The ofs_in_node is used by only data page. It represents offset
 389 * from node's page's beginning to get a data block address.
 390 * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
 391 */
 392#define ENTRIES_IN_SUM          512
 393#define SUMMARY_SIZE            (7)     /* sizeof(struct summary) */
 394#define SUM_FOOTER_SIZE         (5)     /* sizeof(struct summary_footer) */
 395#define SUM_ENTRY_SIZE          (SUMMARY_SIZE * ENTRIES_IN_SUM)
 396
 397/* a summary entry for a 4KB-sized block in a segment */
 398struct f2fs_summary {
 399        __le32 nid;             /* parent node id */
 400        union {
 401                __u8 reserved[3];
 402                struct {
 403                        __u8 version;           /* node version number */
 404                        __le16 ofs_in_node;     /* block index in parent node */
 405                } __packed;
 406        };
 407} __packed;
 408
 409/* summary block type, node or data, is stored to the summary_footer */
 410#define SUM_TYPE_NODE           (1)
 411#define SUM_TYPE_DATA           (0)
 412
 413struct summary_footer {
 414        unsigned char entry_type;       /* SUM_TYPE_XXX */
 415        __le32 check_sum;               /* summary checksum */
 416} __packed;
 417
 418#define SUM_JOURNAL_SIZE        (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
 419                                SUM_ENTRY_SIZE)
 420#define NAT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 421                                sizeof(struct nat_journal_entry))
 422#define NAT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 423                                sizeof(struct nat_journal_entry))
 424#define SIT_JOURNAL_ENTRIES     ((SUM_JOURNAL_SIZE - 2) /\
 425                                sizeof(struct sit_journal_entry))
 426#define SIT_JOURNAL_RESERVED    ((SUM_JOURNAL_SIZE - 2) %\
 427                                sizeof(struct sit_journal_entry))
 428
 429/* Reserved area should make size of f2fs_extra_info equals to
 430 * that of nat_journal and sit_journal.
 431 */
 432#define EXTRA_INFO_RESERVED     (SUM_JOURNAL_SIZE - 2 - 8)
 433
 434/*
 435 * frequently updated NAT/SIT entries can be stored in the spare area in
 436 * summary blocks
 437 */
 438enum {
 439        NAT_JOURNAL = 0,
 440        SIT_JOURNAL
 441};
 442
 443struct nat_journal_entry {
 444        __le32 nid;
 445        struct f2fs_nat_entry ne;
 446} __packed;
 447
 448struct nat_journal {
 449        struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
 450        __u8 reserved[NAT_JOURNAL_RESERVED];
 451} __packed;
 452
 453struct sit_journal_entry {
 454        __le32 segno;
 455        struct f2fs_sit_entry se;
 456} __packed;
 457
 458struct sit_journal {
 459        struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
 460        __u8 reserved[SIT_JOURNAL_RESERVED];
 461} __packed;
 462
 463struct f2fs_extra_info {
 464        __le64 kbytes_written;
 465        __u8 reserved[EXTRA_INFO_RESERVED];
 466} __packed;
 467
 468struct f2fs_journal {
 469        union {
 470                __le16 n_nats;
 471                __le16 n_sits;
 472        };
 473        /* spare area is used by NAT or SIT journals or extra info */
 474        union {
 475                struct nat_journal nat_j;
 476                struct sit_journal sit_j;
 477                struct f2fs_extra_info info;
 478        };
 479} __packed;
 480
 481/* 4KB-sized summary block structure */
 482struct f2fs_summary_block {
 483        struct f2fs_summary entries[ENTRIES_IN_SUM];
 484        struct f2fs_journal journal;
 485        struct summary_footer footer;
 486} __packed;
 487
 488/*
 489 * For directory operations
 490 */
 491#define F2FS_DOT_HASH           0
 492#define F2FS_DDOT_HASH          F2FS_DOT_HASH
 493#define F2FS_MAX_HASH           (~((0x3ULL) << 62))
 494#define F2FS_HASH_COL_BIT       ((0x1ULL) << 63)
 495
 496typedef __le32  f2fs_hash_t;
 497
 498/* One directory entry slot covers 8bytes-long file name */
 499#define F2FS_SLOT_LEN           8
 500#define F2FS_SLOT_LEN_BITS      3
 501
 502#define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
 503
 504/* MAX level for dir lookup */
 505#define MAX_DIR_HASH_DEPTH      63
 506
 507/* MAX buckets in one level of dir */
 508#define MAX_DIR_BUCKETS         (1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
 509
 510/*
 511 * space utilization of regular dentry and inline dentry (w/o extra reservation)
 512 *              regular dentry          inline dentry (def)     inline dentry (min)
 513 * bitmap       1 * 27 = 27             1 * 23 = 23             1 * 1 = 1
 514 * reserved     1 * 3 = 3               1 * 7 = 7               1 * 1 = 1
 515 * dentry       11 * 214 = 2354         11 * 182 = 2002         11 * 2 = 22
 516 * filename     8 * 214 = 1712          8 * 182 = 1456          8 * 2 = 16
 517 * total        4096                    3488                    40
 518 *
 519 * Note: there are more reserved space in inline dentry than in regular
 520 * dentry, when converting inline dentry we should handle this carefully.
 521 */
 522#define NR_DENTRY_IN_BLOCK      214     /* the number of dentry in a block */
 523#define SIZE_OF_DIR_ENTRY       11      /* by byte */
 524#define SIZE_OF_DENTRY_BITMAP   ((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
 525                                        BITS_PER_BYTE)
 526#define SIZE_OF_RESERVED        (PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
 527                                F2FS_SLOT_LEN) * \
 528                                NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
 529#define MIN_INLINE_DENTRY_SIZE          40      /* just include '.' and '..' entries */
 530
 531/* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
 532struct f2fs_dir_entry {
 533        __le32 hash_code;       /* hash code of file name */
 534        __le32 ino;             /* inode number */
 535        __le16 name_len;        /* length of file name */
 536        __u8 file_type;         /* file type */
 537} __packed;
 538
 539/* 4KB-sized directory entry block */
 540struct f2fs_dentry_block {
 541        /* validity bitmap for directory entries in each block */
 542        __u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
 543        __u8 reserved[SIZE_OF_RESERVED];
 544        struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
 545        __u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
 546} __packed;
 547
 548/* file types used in inode_info->flags */
 549enum {
 550        F2FS_FT_UNKNOWN,
 551        F2FS_FT_REG_FILE,
 552        F2FS_FT_DIR,
 553        F2FS_FT_CHRDEV,
 554        F2FS_FT_BLKDEV,
 555        F2FS_FT_FIFO,
 556        F2FS_FT_SOCK,
 557        F2FS_FT_SYMLINK,
 558        F2FS_FT_MAX
 559};
 560
 561#define S_SHIFT 12
 562
 563#define F2FS_DEF_PROJID         0       /* default project ID */
 564
 565#endif  /* _LINUX_F2FS_FS_H */
 566