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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 | /* * Copyright (c) 2000,2005 Silicon Graphics, Inc. * All Rights Reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation. * * This program is distributed in the hope that it would be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef __XFS_DIR2_DATA_H__ #define __XFS_DIR2_DATA_H__ /* * Directory format 2, data block structures. */ struct xfs_dabuf; struct xfs_da_args; struct xfs_inode; struct xfs_trans; /* * Constants. */ #define XFS_DIR2_DATA_MAGIC 0x58443244 /* XD2D: for multiblock dirs */ #define XFS_DIR2_DATA_ALIGN_LOG 3 /* i.e., 8 bytes */ #define XFS_DIR2_DATA_ALIGN (1 << XFS_DIR2_DATA_ALIGN_LOG) #define XFS_DIR2_DATA_FREE_TAG 0xffff #define XFS_DIR2_DATA_FD_COUNT 3 /* * Directory address space divided into sections, * spaces separated by 32GB. */ #define XFS_DIR2_SPACE_SIZE (1ULL << (32 + XFS_DIR2_DATA_ALIGN_LOG)) #define XFS_DIR2_DATA_SPACE 0 #define XFS_DIR2_DATA_OFFSET (XFS_DIR2_DATA_SPACE * XFS_DIR2_SPACE_SIZE) #define XFS_DIR2_DATA_FIRSTDB(mp) \ xfs_dir2_byte_to_db(mp, XFS_DIR2_DATA_OFFSET) /* * Offsets of . and .. in data space (always block 0) */ #define XFS_DIR2_DATA_DOT_OFFSET \ ((xfs_dir2_data_aoff_t)sizeof(xfs_dir2_data_hdr_t)) #define XFS_DIR2_DATA_DOTDOT_OFFSET \ (XFS_DIR2_DATA_DOT_OFFSET + xfs_dir2_data_entsize(1)) #define XFS_DIR2_DATA_FIRST_OFFSET \ (XFS_DIR2_DATA_DOTDOT_OFFSET + xfs_dir2_data_entsize(2)) /* * Structures. */ /* * Describe a free area in the data block. * The freespace will be formatted as a xfs_dir2_data_unused_t. */ typedef struct xfs_dir2_data_free { __be16 offset; /* start of freespace */ __be16 length; /* length of freespace */ } xfs_dir2_data_free_t; /* * Header for the data blocks. * Always at the beginning of a directory-sized block. * The code knows that XFS_DIR2_DATA_FD_COUNT is 3. */ typedef struct xfs_dir2_data_hdr { __be32 magic; /* XFS_DIR2_DATA_MAGIC */ /* or XFS_DIR2_BLOCK_MAGIC */ xfs_dir2_data_free_t bestfree[XFS_DIR2_DATA_FD_COUNT]; } xfs_dir2_data_hdr_t; /* * Active entry in a data block. Aligned to 8 bytes. * Tag appears as the last 2 bytes. */ typedef struct xfs_dir2_data_entry { __be64 inumber; /* inode number */ __u8 namelen; /* name length */ __u8 name[1]; /* name bytes, no null */ /* variable offset */ __be16 tag; /* starting offset of us */ } xfs_dir2_data_entry_t; /* * Unused entry in a data block. Aligned to 8 bytes. * Tag appears as the last 2 bytes. */ typedef struct xfs_dir2_data_unused { __be16 freetag; /* XFS_DIR2_DATA_FREE_TAG */ __be16 length; /* total free length */ /* variable offset */ __be16 tag; /* starting offset of us */ } xfs_dir2_data_unused_t; typedef union { xfs_dir2_data_entry_t entry; xfs_dir2_data_unused_t unused; } xfs_dir2_data_union_t; /* * Generic data block structure, for xfs_db. */ typedef struct xfs_dir2_data { xfs_dir2_data_hdr_t hdr; /* magic XFS_DIR2_DATA_MAGIC */ xfs_dir2_data_union_t u[1]; } xfs_dir2_data_t; /* * Macros. */ /* * Size of a data entry. */ static inline int xfs_dir2_data_entsize(int n) { return (int)roundup(offsetof(xfs_dir2_data_entry_t, name[0]) + (n) + \ (uint)sizeof(xfs_dir2_data_off_t), XFS_DIR2_DATA_ALIGN); } /* * Pointer to an entry's tag word. */ static inline __be16 * xfs_dir2_data_entry_tag_p(xfs_dir2_data_entry_t *dep) { return (__be16 *)((char *)dep + xfs_dir2_data_entsize(dep->namelen) - sizeof(__be16)); } /* * Pointer to a freespace's tag word. */ static inline __be16 * xfs_dir2_data_unused_tag_p(xfs_dir2_data_unused_t *dup) { return (__be16 *)((char *)dup + be16_to_cpu(dup->length) - sizeof(__be16)); } /* * Function declarations. */ #ifdef DEBUG extern void xfs_dir2_data_check(struct xfs_inode *dp, struct xfs_dabuf *bp); #else #define xfs_dir2_data_check(dp,bp) #endif extern xfs_dir2_data_free_t *xfs_dir2_data_freefind(xfs_dir2_data_t *d, xfs_dir2_data_unused_t *dup); extern xfs_dir2_data_free_t *xfs_dir2_data_freeinsert(xfs_dir2_data_t *d, xfs_dir2_data_unused_t *dup, int *loghead); extern void xfs_dir2_data_freescan(struct xfs_mount *mp, xfs_dir2_data_t *d, int *loghead); extern int xfs_dir2_data_init(struct xfs_da_args *args, xfs_dir2_db_t blkno, struct xfs_dabuf **bpp); extern void xfs_dir2_data_log_entry(struct xfs_trans *tp, struct xfs_dabuf *bp, xfs_dir2_data_entry_t *dep); extern void xfs_dir2_data_log_header(struct xfs_trans *tp, struct xfs_dabuf *bp); extern void xfs_dir2_data_log_unused(struct xfs_trans *tp, struct xfs_dabuf *bp, xfs_dir2_data_unused_t *dup); extern void xfs_dir2_data_make_free(struct xfs_trans *tp, struct xfs_dabuf *bp, xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp); extern void xfs_dir2_data_use_free(struct xfs_trans *tp, struct xfs_dabuf *bp, xfs_dir2_data_unused_t *dup, xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp); #endif /* __XFS_DIR2_DATA_H__ */ |