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