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 13 /* 14 * Directory/attribute geometry information. There will be one of these for each 15 * data fork type, and it will be passed around via the xfs_da_args. Global 16 * structures will be attached to the xfs_mount. 17 */ 18 struct xfs_da_geometry { 19 unsigned int blksize; /* da block size in bytes */ 20 unsigned int fsbcount; /* da block size in filesystem blocks */ 21 uint8_t fsblog; /* log2 of _filesystem_ block size */ 22 uint8_t blklog; /* log2 of da block size */ 23 unsigned int node_hdr_size; /* danode header size in bytes */ 24 unsigned int node_ents; /* # of entries in a danode */ 25 unsigned int magicpct; /* 37% of block size in bytes */ 26 xfs_dablk_t datablk; /* blockno of dir data v2 */ 27 unsigned int leaf_hdr_size; /* dir2 leaf header size */ 28 unsigned int leaf_max_ents; /* # of entries in dir2 leaf */ 29 xfs_dablk_t leafblk; /* blockno of leaf data v2 */ 30 unsigned int free_hdr_size; /* dir2 free header size */ 31 unsigned int free_max_bests; /* # of bests entries in dir2 free */ 32 xfs_dablk_t freeblk; /* blockno of free data v2 */ 33 xfs_extnum_t max_extents; /* Max. extents in corresponding fork */ 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 uint32_t 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 (1u << 0) /* check for ok with no space */ 88 #define XFS_DA_OP_REPLACE (1u << 1) /* this is an atomic replace op */ 89 #define XFS_DA_OP_ADDNAME (1u << 2) /* this is an add operation */ 90 #define XFS_DA_OP_OKNOENT (1u << 3) /* lookup op, ENOENT ok, else die */ 91 #define XFS_DA_OP_CILOOKUP (1u << 4) /* lookup returns CI name if found */ 92 #define XFS_DA_OP_NOTIME (1u << 5) /* don't update inode timestamps */ 93 #define XFS_DA_OP_REMOVE (1u << 6) /* this is a remove operation */ 94 #define XFS_DA_OP_RECOVERY (1u << 7) /* Log recovery operation */ 95 96 #define XFS_DA_OP_FLAGS \ 97 { XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \ 98 { XFS_DA_OP_REPLACE, "REPLACE" }, \ 99 { XFS_DA_OP_ADDNAME, "ADDNAME" }, \ 100 { XFS_DA_OP_OKNOENT, "OKNOENT" }, \ 101 { XFS_DA_OP_CILOOKUP, "CILOOKUP" }, \ 102 { XFS_DA_OP_NOTIME, "NOTIME" }, \ 103 { XFS_DA_OP_REMOVE, "REMOVE" }, \ 104 { XFS_DA_OP_RECOVERY, "RECOVERY" } 105 106 /* 107 * Storage for holding state during Btree searches and split/join ops. 108 * 109 * Only need space for 5 intermediate nodes. With a minimum of 62-way 110 * fanout to the Btree, we can support over 900 million directory blocks, 111 * which is slightly more than enough. 112 */ 113 typedef struct xfs_da_state_blk { 114 struct xfs_buf *bp; /* buffer containing block */ 115 xfs_dablk_t blkno; /* filesystem blkno of buffer */ 116 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */ 117 int index; /* relevant index into block */ 118 xfs_dahash_t hashval; /* last hash value in block */ 119 int magic; /* blk's magic number, ie: blk type */ 120 } xfs_da_state_blk_t; 121 122 typedef struct xfs_da_state_path { 123 int active; /* number of active levels */ 124 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH]; 125 } xfs_da_state_path_t; 126 127 typedef struct xfs_da_state { 128 xfs_da_args_t *args; /* filename arguments */ 129 struct xfs_mount *mp; /* filesystem mount point */ 130 xfs_da_state_path_t path; /* search/split paths */ 131 xfs_da_state_path_t altpath; /* alternate path for join */ 132 unsigned char inleaf; /* insert into 1->lf, 0->splf */ 133 unsigned char extravalid; /* T/F: extrablk is in use */ 134 unsigned char extraafter; /* T/F: extrablk is after new */ 135 xfs_da_state_blk_t extrablk; /* for double-splits on leaves */ 136 /* for dirv2 extrablk is data */ 137 } xfs_da_state_t; 138 139 /* 140 * In-core version of the node header to abstract the differences in the v2 and 141 * v3 disk format of the headers. Callers need to convert to/from disk format as 142 * appropriate. 143 */ 144 struct xfs_da3_icnode_hdr { 145 uint32_t forw; 146 uint32_t back; 147 uint16_t magic; 148 uint16_t count; 149 uint16_t level; 150 151 /* 152 * Pointer to the on-disk format entries, which are behind the 153 * variable size (v4 vs v5) header in the on-disk block. 154 */ 155 struct xfs_da_node_entry *btree; 156 }; 157 158 /* 159 * Utility macros to aid in logging changed structure fields. 160 */ 161 #define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE)) 162 #define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \ 163 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \ 164 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1) 165 166 /*======================================================================== 167 * Function prototypes. 168 *========================================================================*/ 169 170 /* 171 * Routines used for growing the Btree. 172 */ 173 int xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno, 174 int level, struct xfs_buf **bpp, int whichfork); 175 int xfs_da3_split(xfs_da_state_t *state); 176 177 /* 178 * Routines used for shrinking the Btree. 179 */ 180 int xfs_da3_join(xfs_da_state_t *state); 181 void xfs_da3_fixhashpath(struct xfs_da_state *state, 182 struct xfs_da_state_path *path_to_to_fix); 183 184 /* 185 * Routines used for finding things in the Btree. 186 */ 187 int xfs_da3_node_lookup_int(xfs_da_state_t *state, int *result); 188 int xfs_da3_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path, 189 int forward, int release, int *result); 190 /* 191 * Utility routines. 192 */ 193 int xfs_da3_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk, 194 xfs_da_state_blk_t *new_blk); 195 int xfs_da3_node_read(struct xfs_trans *tp, struct xfs_inode *dp, 196 xfs_dablk_t bno, struct xfs_buf **bpp, int whichfork); 197 int xfs_da3_node_read_mapped(struct xfs_trans *tp, struct xfs_inode *dp, 198 xfs_daddr_t mappedbno, struct xfs_buf **bpp, 199 int whichfork); 200 201 /* 202 * Utility routines. 203 */ 204 205 #define XFS_DABUF_MAP_HOLE_OK (1u << 0) 206 207 int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno); 208 int xfs_da_grow_inode_int(struct xfs_da_args *args, xfs_fileoff_t *bno, 209 int count); 210 int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp, 211 xfs_dablk_t bno, struct xfs_buf **bp, int whichfork); 212 int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp, 213 xfs_dablk_t bno, unsigned int flags, struct xfs_buf **bpp, 214 int whichfork, const struct xfs_buf_ops *ops); 215 int xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno, 216 unsigned int flags, int whichfork, 217 const struct xfs_buf_ops *ops); 218 int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno, 219 struct xfs_buf *dead_buf); 220 221 uint xfs_da_hashname(const uint8_t *name_string, int name_length); 222 enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args, 223 const unsigned char *name, int len); 224 225 226 struct xfs_da_state *xfs_da_state_alloc(struct xfs_da_args *args); 227 void xfs_da_state_free(xfs_da_state_t *state); 228 void xfs_da_state_reset(struct xfs_da_state *state, struct xfs_da_args *args); 229 230 void xfs_da3_node_hdr_from_disk(struct xfs_mount *mp, 231 struct xfs_da3_icnode_hdr *to, struct xfs_da_intnode *from); 232 void xfs_da3_node_hdr_to_disk(struct xfs_mount *mp, 233 struct xfs_da_intnode *to, struct xfs_da3_icnode_hdr *from); 234 235 extern struct kmem_cache *xfs_da_state_cache; 236 237 #endif /* __XFS_DA_BTREE_H__ */ 238