1 /* 2 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc. 3 * Copyright (c) 2013 Red Hat, Inc. 4 * All Rights Reserved. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it would be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 18 */ 19 #ifndef __XFS_DA_BTREE_H__ 20 #define __XFS_DA_BTREE_H__ 21 22 struct xfs_defer_ops; 23 struct xfs_inode; 24 struct xfs_trans; 25 struct zone; 26 struct xfs_dir_ops; 27 28 /* 29 * Directory/attribute geometry information. There will be one of these for each 30 * data fork type, and it will be passed around via the xfs_da_args. Global 31 * structures will be attached to the xfs_mount. 32 */ 33 struct xfs_da_geometry { 34 int blksize; /* da block size in bytes */ 35 int fsbcount; /* da block size in filesystem blocks */ 36 uint8_t fsblog; /* log2 of _filesystem_ block size */ 37 uint8_t blklog; /* log2 of da block size */ 38 uint node_ents; /* # of entries in a danode */ 39 int magicpct; /* 37% of block size in bytes */ 40 xfs_dablk_t datablk; /* blockno of dir data v2 */ 41 xfs_dablk_t leafblk; /* blockno of leaf data v2 */ 42 xfs_dablk_t freeblk; /* blockno of free data v2 */ 43 }; 44 45 /*======================================================================== 46 * Btree searching and modification structure definitions. 47 *========================================================================*/ 48 49 /* 50 * Search comparison results 51 */ 52 enum xfs_dacmp { 53 XFS_CMP_DIFFERENT, /* names are completely different */ 54 XFS_CMP_EXACT, /* names are exactly the same */ 55 XFS_CMP_CASE /* names are same but differ in case */ 56 }; 57 58 /* 59 * Structure to ease passing around component names. 60 */ 61 typedef struct xfs_da_args { 62 struct xfs_da_geometry *geo; /* da block geometry */ 63 const __uint8_t *name; /* string (maybe not NULL terminated) */ 64 int namelen; /* length of string (maybe no NULL) */ 65 __uint8_t filetype; /* filetype of inode for directories */ 66 __uint8_t *value; /* set of bytes (maybe contain NULLs) */ 67 int valuelen; /* length of value */ 68 int flags; /* argument flags (eg: ATTR_NOCREATE) */ 69 xfs_dahash_t hashval; /* hash value of name */ 70 xfs_ino_t inumber; /* input/output inode number */ 71 struct xfs_inode *dp; /* directory inode to manipulate */ 72 xfs_fsblock_t *firstblock; /* ptr to firstblock for bmap calls */ 73 struct xfs_defer_ops *dfops; /* ptr to freelist for bmap_finish */ 74 struct xfs_trans *trans; /* current trans (changes over time) */ 75 xfs_extlen_t total; /* total blocks needed, for 1st bmap */ 76 int whichfork; /* data or attribute fork */ 77 xfs_dablk_t blkno; /* blkno of attr leaf of interest */ 78 int index; /* index of attr of interest in blk */ 79 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */ 80 int rmtblkcnt; /* remote attr value block count */ 81 int rmtvaluelen; /* remote attr value length in bytes */ 82 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */ 83 int index2; /* index of 2nd attr in blk */ 84 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */ 85 int rmtblkcnt2; /* remote attr value block count */ 86 int rmtvaluelen2; /* remote attr value length in bytes */ 87 int op_flags; /* operation flags */ 88 enum xfs_dacmp cmpresult; /* name compare result for lookups */ 89 } xfs_da_args_t; 90 91 /* 92 * Operation flags: 93 */ 94 #define XFS_DA_OP_JUSTCHECK 0x0001 /* check for ok with no space */ 95 #define XFS_DA_OP_RENAME 0x0002 /* this is an atomic rename op */ 96 #define XFS_DA_OP_ADDNAME 0x0004 /* this is an add operation */ 97 #define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */ 98 #define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */ 99 100 #define XFS_DA_OP_FLAGS \ 101 { XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \ 102 { XFS_DA_OP_RENAME, "RENAME" }, \ 103 { XFS_DA_OP_ADDNAME, "ADDNAME" }, \ 104 { XFS_DA_OP_OKNOENT, "OKNOENT" }, \ 105 { XFS_DA_OP_CILOOKUP, "CILOOKUP" } 106 107 /* 108 * Storage for holding state during Btree searches and split/join ops. 109 * 110 * Only need space for 5 intermediate nodes. With a minimum of 62-way 111 * fanout to the Btree, we can support over 900 million directory blocks, 112 * which is slightly more than enough. 113 */ 114 typedef struct xfs_da_state_blk { 115 struct xfs_buf *bp; /* buffer containing block */ 116 xfs_dablk_t blkno; /* filesystem blkno of buffer */ 117 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */ 118 int index; /* relevant index into block */ 119 xfs_dahash_t hashval; /* last hash value in block */ 120 int magic; /* blk's magic number, ie: blk type */ 121 } xfs_da_state_blk_t; 122 123 typedef struct xfs_da_state_path { 124 int active; /* number of active levels */ 125 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH]; 126 } xfs_da_state_path_t; 127 128 typedef struct xfs_da_state { 129 xfs_da_args_t *args; /* filename arguments */ 130 struct xfs_mount *mp; /* filesystem mount point */ 131 xfs_da_state_path_t path; /* search/split paths */ 132 xfs_da_state_path_t altpath; /* alternate path for join */ 133 unsigned char inleaf; /* insert into 1->lf, 0->splf */ 134 unsigned char extravalid; /* T/F: extrablk is in use */ 135 unsigned char extraafter; /* T/F: extrablk is after new */ 136 xfs_da_state_blk_t extrablk; /* for double-splits on leaves */ 137 /* for dirv2 extrablk is data */ 138 } xfs_da_state_t; 139 140 /* 141 * Utility macros to aid in logging changed structure fields. 142 */ 143 #define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE)) 144 #define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \ 145 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \ 146 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1) 147 148 /* 149 * Name ops for directory and/or attr name operations 150 */ 151 struct xfs_nameops { 152 xfs_dahash_t (*hashname)(struct xfs_name *); 153 enum xfs_dacmp (*compname)(struct xfs_da_args *, 154 const unsigned char *, int); 155 }; 156 157 158 /*======================================================================== 159 * Function prototypes. 160 *========================================================================*/ 161 162 /* 163 * Routines used for growing the Btree. 164 */ 165 int xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno, 166 int level, struct xfs_buf **bpp, int whichfork); 167 int xfs_da3_split(xfs_da_state_t *state); 168 169 /* 170 * Routines used for shrinking the Btree. 171 */ 172 int xfs_da3_join(xfs_da_state_t *state); 173 void xfs_da3_fixhashpath(struct xfs_da_state *state, 174 struct xfs_da_state_path *path_to_to_fix); 175 176 /* 177 * Routines used for finding things in the Btree. 178 */ 179 int xfs_da3_node_lookup_int(xfs_da_state_t *state, int *result); 180 int xfs_da3_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path, 181 int forward, int release, int *result); 182 /* 183 * Utility routines. 184 */ 185 int xfs_da3_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk, 186 xfs_da_state_blk_t *new_blk); 187 int xfs_da3_node_read(struct xfs_trans *tp, struct xfs_inode *dp, 188 xfs_dablk_t bno, xfs_daddr_t mappedbno, 189 struct xfs_buf **bpp, int which_fork); 190 191 /* 192 * Utility routines. 193 */ 194 int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno); 195 int xfs_da_grow_inode_int(struct xfs_da_args *args, xfs_fileoff_t *bno, 196 int count); 197 int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp, 198 xfs_dablk_t bno, xfs_daddr_t mappedbno, 199 struct xfs_buf **bp, int whichfork); 200 int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp, 201 xfs_dablk_t bno, xfs_daddr_t mappedbno, 202 struct xfs_buf **bpp, int whichfork, 203 const struct xfs_buf_ops *ops); 204 int xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno, 205 xfs_daddr_t mapped_bno, int whichfork, 206 const struct xfs_buf_ops *ops); 207 int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno, 208 struct xfs_buf *dead_buf); 209 210 uint xfs_da_hashname(const __uint8_t *name_string, int name_length); 211 enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args, 212 const unsigned char *name, int len); 213 214 215 xfs_da_state_t *xfs_da_state_alloc(void); 216 void xfs_da_state_free(xfs_da_state_t *state); 217 218 extern struct kmem_zone *xfs_da_state_zone; 219 extern const struct xfs_nameops xfs_default_nameops; 220 221 #endif /* __XFS_DA_BTREE_H__ */ 222