1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc. 4 * Copyright (c) 2013 Red Hat, Inc. 5 * All Rights Reserved. 6 */ 7 #ifndef __XFS_DA_BTREE_H__ 8 #define __XFS_DA_BTREE_H__ 9 10 struct xfs_inode; 11 struct xfs_trans; 12 struct zone; 13 14 /* 15 * Directory/attribute geometry information. There will be one of these for each 16 * data fork type, and it will be passed around via the xfs_da_args. Global 17 * structures will be attached to the xfs_mount. 18 */ 19 struct xfs_da_geometry { 20 unsigned int blksize; /* da block size in bytes */ 21 unsigned int fsbcount; /* da block size in filesystem blocks */ 22 uint8_t fsblog; /* log2 of _filesystem_ block size */ 23 uint8_t blklog; /* log2 of da block size */ 24 unsigned int node_hdr_size; /* danode header size in bytes */ 25 unsigned int node_ents; /* # of entries in a danode */ 26 unsigned int magicpct; /* 37% of block size in bytes */ 27 xfs_dablk_t datablk; /* blockno of dir data v2 */ 28 unsigned int leaf_hdr_size; /* dir2 leaf header size */ 29 unsigned int leaf_max_ents; /* # of entries in dir2 leaf */ 30 xfs_dablk_t leafblk; /* blockno of leaf data v2 */ 31 unsigned int free_hdr_size; /* dir2 free header size */ 32 unsigned int free_max_bests; /* # of bests entries in dir2 free */ 33 xfs_dablk_t freeblk; /* blockno of free data v2 */ 34 35 xfs_dir2_data_aoff_t data_first_offset; 36 size_t data_entry_offset; 37 }; 38 39 /*======================================================================== 40 * Btree searching and modification structure definitions. 41 *========================================================================*/ 42 43 /* 44 * Search comparison results 45 */ 46 enum xfs_dacmp { 47 XFS_CMP_DIFFERENT, /* names are completely different */ 48 XFS_CMP_EXACT, /* names are exactly the same */ 49 XFS_CMP_CASE /* names are same but differ in case */ 50 }; 51 52 /* 53 * Structure to ease passing around component names. 54 */ 55 typedef struct xfs_da_args { 56 struct xfs_da_geometry *geo; /* da block geometry */ 57 const uint8_t *name; /* string (maybe not NULL terminated) */ 58 int namelen; /* length of string (maybe no NULL) */ 59 uint8_t filetype; /* filetype of inode for directories */ 60 void *value; /* set of bytes (maybe contain NULLs) */ 61 int valuelen; /* length of value */ 62 unsigned int attr_filter; /* XFS_ATTR_{ROOT,SECURE,INCOMPLETE} */ 63 unsigned int attr_flags; /* XATTR_{CREATE,REPLACE} */ 64 xfs_dahash_t hashval; /* hash value of name */ 65 xfs_ino_t inumber; /* input/output inode number */ 66 struct xfs_inode *dp; /* directory inode to manipulate */ 67 struct xfs_trans *trans; /* current trans (changes over time) */ 68 xfs_extlen_t total; /* total blocks needed, for 1st bmap */ 69 int whichfork; /* data or attribute fork */ 70 xfs_dablk_t blkno; /* blkno of attr leaf of interest */ 71 int index; /* index of attr of interest in blk */ 72 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */ 73 int rmtblkcnt; /* remote attr value block count */ 74 int rmtvaluelen; /* remote attr value length in bytes */ 75 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */ 76 int index2; /* index of 2nd attr in blk */ 77 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */ 78 int rmtblkcnt2; /* remote attr value block count */ 79 int rmtvaluelen2; /* remote attr value length in bytes */ 80 int op_flags; /* operation flags */ 81 enum xfs_dacmp cmpresult; /* name compare result for lookups */ 82 } xfs_da_args_t; 83 84 /* 85 * Operation flags: 86 */ 87 #define XFS_DA_OP_JUSTCHECK 0x0001 /* check for ok with no space */ 88 #define XFS_DA_OP_RENAME 0x0002 /* this is an atomic rename op */ 89 #define XFS_DA_OP_ADDNAME 0x0004 /* this is an add operation */ 90 #define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */ 91 #define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */ 92 #define XFS_DA_OP_NOTIME 0x0020 /* don't update inode timestamps */ 93 94 #define XFS_DA_OP_FLAGS \ 95 { XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \ 96 { XFS_DA_OP_RENAME, "RENAME" }, \ 97 { XFS_DA_OP_ADDNAME, "ADDNAME" }, \ 98 { XFS_DA_OP_OKNOENT, "OKNOENT" }, \ 99 { XFS_DA_OP_CILOOKUP, "CILOOKUP" }, \ 100 { XFS_DA_OP_NOTIME, "NOTIME" } 101 102 /* 103 * Storage for holding state during Btree searches and split/join ops. 104 * 105 * Only need space for 5 intermediate nodes. With a minimum of 62-way 106 * fanout to the Btree, we can support over 900 million directory blocks, 107 * which is slightly more than enough. 108 */ 109 typedef struct xfs_da_state_blk { 110 struct xfs_buf *bp; /* buffer containing block */ 111 xfs_dablk_t blkno; /* filesystem blkno of buffer */ 112 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */ 113 int index; /* relevant index into block */ 114 xfs_dahash_t hashval; /* last hash value in block */ 115 int magic; /* blk's magic number, ie: blk type */ 116 } xfs_da_state_blk_t; 117 118 typedef struct xfs_da_state_path { 119 int active; /* number of active levels */ 120 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH]; 121 } xfs_da_state_path_t; 122 123 typedef struct xfs_da_state { 124 xfs_da_args_t *args; /* filename arguments */ 125 struct xfs_mount *mp; /* filesystem mount point */ 126 xfs_da_state_path_t path; /* search/split paths */ 127 xfs_da_state_path_t altpath; /* alternate path for join */ 128 unsigned char inleaf; /* insert into 1->lf, 0->splf */ 129 unsigned char extravalid; /* T/F: extrablk is in use */ 130 unsigned char extraafter; /* T/F: extrablk is after new */ 131 xfs_da_state_blk_t extrablk; /* for double-splits on leaves */ 132 /* for dirv2 extrablk is data */ 133 } xfs_da_state_t; 134 135 /* 136 * In-core version of the node header to abstract the differences in the v2 and 137 * v3 disk format of the headers. Callers need to convert to/from disk format as 138 * appropriate. 139 */ 140 struct xfs_da3_icnode_hdr { 141 uint32_t forw; 142 uint32_t back; 143 uint16_t magic; 144 uint16_t count; 145 uint16_t level; 146 147 /* 148 * Pointer to the on-disk format entries, which are behind the 149 * variable size (v4 vs v5) header in the on-disk block. 150 */ 151 struct xfs_da_node_entry *btree; 152 }; 153 154 /* 155 * Utility macros to aid in logging changed structure fields. 156 */ 157 #define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE)) 158 #define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \ 159 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \ 160 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1) 161 162 /*======================================================================== 163 * Function prototypes. 164 *========================================================================*/ 165 166 /* 167 * Routines used for growing the Btree. 168 */ 169 int xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno, 170 int level, struct xfs_buf **bpp, int whichfork); 171 int xfs_da3_split(xfs_da_state_t *state); 172 173 /* 174 * Routines used for shrinking the Btree. 175 */ 176 int xfs_da3_join(xfs_da_state_t *state); 177 void xfs_da3_fixhashpath(struct xfs_da_state *state, 178 struct xfs_da_state_path *path_to_to_fix); 179 180 /* 181 * Routines used for finding things in the Btree. 182 */ 183 int xfs_da3_node_lookup_int(xfs_da_state_t *state, int *result); 184 int xfs_da3_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path, 185 int forward, int release, int *result); 186 /* 187 * Utility routines. 188 */ 189 int xfs_da3_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk, 190 xfs_da_state_blk_t *new_blk); 191 int xfs_da3_node_read(struct xfs_trans *tp, struct xfs_inode *dp, 192 xfs_dablk_t bno, struct xfs_buf **bpp, int whichfork); 193 int xfs_da3_node_read_mapped(struct xfs_trans *tp, struct xfs_inode *dp, 194 xfs_daddr_t mappedbno, struct xfs_buf **bpp, 195 int whichfork); 196 197 /* 198 * Utility routines. 199 */ 200 201 #define XFS_DABUF_MAP_HOLE_OK (1 << 0) 202 203 int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno); 204 int xfs_da_grow_inode_int(struct xfs_da_args *args, xfs_fileoff_t *bno, 205 int count); 206 int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp, 207 xfs_dablk_t bno, struct xfs_buf **bp, int whichfork); 208 int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp, 209 xfs_dablk_t bno, unsigned int flags, struct xfs_buf **bpp, 210 int whichfork, const struct xfs_buf_ops *ops); 211 int xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno, 212 unsigned int flags, int whichfork, 213 const struct xfs_buf_ops *ops); 214 int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno, 215 struct xfs_buf *dead_buf); 216 217 uint xfs_da_hashname(const uint8_t *name_string, int name_length); 218 enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args, 219 const unsigned char *name, int len); 220 221 222 xfs_da_state_t *xfs_da_state_alloc(void); 223 void xfs_da_state_free(xfs_da_state_t *state); 224 225 void xfs_da3_node_hdr_from_disk(struct xfs_mount *mp, 226 struct xfs_da3_icnode_hdr *to, struct xfs_da_intnode *from); 227 void xfs_da3_node_hdr_to_disk(struct xfs_mount *mp, 228 struct xfs_da_intnode *to, struct xfs_da3_icnode_hdr *from); 229 230 extern struct kmem_zone *xfs_da_state_zone; 231 232 #endif /* __XFS_DA_BTREE_H__ */ 233