1 /* 2 * Copyright (c) 2000, 2002 Silicon Graphics, Inc. All Rights Reserved. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms of version 2 of the GNU General Public License as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it would be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 11 * 12 * Further, this software is distributed without any warranty that it is 13 * free of the rightful claim of any third person regarding infringement 14 * or the like. Any license provided herein, whether implied or 15 * otherwise, applies only to this software file. Patent licenses, if 16 * any, provided herein do not apply to combinations of this program with 17 * other software, or any other product whatsoever. 18 * 19 * You should have received a copy of the GNU General Public License along 20 * with this program; if not, write the Free Software Foundation, Inc., 59 21 * Temple Place - Suite 330, Boston MA 02111-1307, USA. 22 * 23 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy, 24 * Mountain View, CA 94043, or: 25 * 26 * http://www.sgi.com 27 * 28 * For further information regarding this notice, see: 29 * 30 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/ 31 */ 32 #ifndef __XFS_DA_BTREE_H__ 33 #define __XFS_DA_BTREE_H__ 34 35 struct xfs_buf; 36 struct xfs_bmap_free; 37 struct xfs_inode; 38 struct xfs_mount; 39 struct xfs_trans; 40 struct zone; 41 42 /*======================================================================== 43 * Directory Structure when greater than XFS_LBSIZE(mp) bytes. 44 *========================================================================*/ 45 46 /* 47 * This structure is common to both leaf nodes and non-leaf nodes in the Btree. 48 * 49 * Is is used to manage a doubly linked list of all blocks at the same 50 * level in the Btree, and to identify which type of block this is. 51 */ 52 #define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */ 53 #define XFS_DIR_LEAF_MAGIC 0xfeeb /* magic number: directory leaf blks */ 54 #define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */ 55 #define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */ 56 #define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */ 57 58 #define XFS_DIRX_LEAF_MAGIC(mp) \ 59 (XFS_DIR_IS_V1(mp) ? XFS_DIR_LEAF_MAGIC : XFS_DIR2_LEAFN_MAGIC) 60 61 typedef struct xfs_da_blkinfo { 62 xfs_dablk_t forw; /* previous block in list */ 63 xfs_dablk_t back; /* following block in list */ 64 __uint16_t magic; /* validity check on block */ 65 __uint16_t pad; /* unused */ 66 } xfs_da_blkinfo_t; 67 68 /* 69 * This is the structure of the root and intermediate nodes in the Btree. 70 * The leaf nodes are defined above. 71 * 72 * Entries are not packed. 73 * 74 * Since we have duplicate keys, use a binary search but always follow 75 * all match in the block, not just the first match found. 76 */ 77 #define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */ 78 79 typedef struct xfs_da_intnode { 80 struct xfs_da_node_hdr { /* constant-structure header block */ 81 xfs_da_blkinfo_t info; /* block type, links, etc. */ 82 __uint16_t count; /* count of active entries */ 83 __uint16_t level; /* level above leaves (leaf == 0) */ 84 } hdr; 85 struct xfs_da_node_entry { 86 xfs_dahash_t hashval; /* hash value for this descendant */ 87 xfs_dablk_t before; /* Btree block before this key */ 88 } btree[1]; /* variable sized array of keys */ 89 } xfs_da_intnode_t; 90 typedef struct xfs_da_node_hdr xfs_da_node_hdr_t; 91 typedef struct xfs_da_node_entry xfs_da_node_entry_t; 92 93 #define XFS_DA_MAXHASH ((xfs_dahash_t)-1) /* largest valid hash value */ 94 95 /* 96 * Macros used by directory code to interface to the filesystem. 97 */ 98 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_LBSIZE) 99 int xfs_lbsize(struct xfs_mount *mp); 100 #define XFS_LBSIZE(mp) xfs_lbsize(mp) 101 #else 102 #define XFS_LBSIZE(mp) ((mp)->m_sb.sb_blocksize) 103 #endif 104 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_LBLOG) 105 int xfs_lblog(struct xfs_mount *mp); 106 #define XFS_LBLOG(mp) xfs_lblog(mp) 107 #else 108 #define XFS_LBLOG(mp) ((mp)->m_sb.sb_blocklog) 109 #endif 110 111 /* 112 * Macros used by directory code to interface to the kernel 113 */ 114 115 /* 116 * Macros used to manipulate directory off_t's 117 */ 118 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_MAKE_BNOENTRY) 119 __uint32_t xfs_da_make_bnoentry(struct xfs_mount *mp, xfs_dablk_t bno, 120 int entry); 121 #define XFS_DA_MAKE_BNOENTRY(mp,bno,entry) \ 122 xfs_da_make_bnoentry(mp,bno,entry) 123 #else 124 #define XFS_DA_MAKE_BNOENTRY(mp,bno,entry) \ 125 (((bno) << (mp)->m_dircook_elog) | (entry)) 126 #endif 127 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_MAKE_COOKIE) 128 xfs_off_t xfs_da_make_cookie(struct xfs_mount *mp, xfs_dablk_t bno, int entry, 129 xfs_dahash_t hash); 130 #define XFS_DA_MAKE_COOKIE(mp,bno,entry,hash) \ 131 xfs_da_make_cookie(mp,bno,entry,hash) 132 #else 133 #define XFS_DA_MAKE_COOKIE(mp,bno,entry,hash) \ 134 (((xfs_off_t)XFS_DA_MAKE_BNOENTRY(mp, bno, entry) << 32) | (hash)) 135 #endif 136 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_COOKIE_HASH) 137 xfs_dahash_t xfs_da_cookie_hash(struct xfs_mount *mp, xfs_off_t cookie); 138 #define XFS_DA_COOKIE_HASH(mp,cookie) xfs_da_cookie_hash(mp,cookie) 139 #else 140 #define XFS_DA_COOKIE_HASH(mp,cookie) ((xfs_dahash_t)(cookie)) 141 #endif 142 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_COOKIE_BNO) 143 xfs_dablk_t xfs_da_cookie_bno(struct xfs_mount *mp, xfs_off_t cookie); 144 #define XFS_DA_COOKIE_BNO(mp,cookie) xfs_da_cookie_bno(mp,cookie) 145 #else 146 #define XFS_DA_COOKIE_BNO(mp,cookie) \ 147 (((xfs_off_t)(cookie) >> 31) == -1LL ? \ 148 (xfs_dablk_t)0 : \ 149 (xfs_dablk_t)((xfs_off_t)(cookie) >> ((mp)->m_dircook_elog + 32))) 150 #endif 151 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_COOKIE_ENTRY) 152 int xfs_da_cookie_entry(struct xfs_mount *mp, xfs_off_t cookie); 153 #define XFS_DA_COOKIE_ENTRY(mp,cookie) xfs_da_cookie_entry(mp,cookie) 154 #else 155 #define XFS_DA_COOKIE_ENTRY(mp,cookie) \ 156 (((xfs_off_t)(cookie) >> 31) == -1LL ? \ 157 (xfs_dablk_t)0 : \ 158 (xfs_dablk_t)(((xfs_off_t)(cookie) >> 32) & \ 159 ((1 << (mp)->m_dircook_elog) - 1))) 160 #endif 161 162 163 /*======================================================================== 164 * Btree searching and modification structure definitions. 165 *========================================================================*/ 166 167 /* 168 * Structure to ease passing around component names. 169 */ 170 typedef struct xfs_da_args { 171 uchar_t *name; /* string (maybe not NULL terminated) */ 172 int namelen; /* length of string (maybe no NULL) */ 173 uchar_t *value; /* set of bytes (maybe contain NULLs) */ 174 int valuelen; /* length of value */ 175 int flags; /* argument flags (eg: ATTR_NOCREATE) */ 176 xfs_dahash_t hashval; /* hash value of name */ 177 xfs_ino_t inumber; /* input/output inode number */ 178 struct xfs_inode *dp; /* directory inode to manipulate */ 179 xfs_fsblock_t *firstblock; /* ptr to firstblock for bmap calls */ 180 struct xfs_bmap_free *flist; /* ptr to freelist for bmap_finish */ 181 struct xfs_trans *trans; /* current trans (changes over time) */ 182 xfs_extlen_t total; /* total blocks needed, for 1st bmap */ 183 int whichfork; /* data or attribute fork */ 184 xfs_dablk_t blkno; /* blkno of attr leaf of interest */ 185 int index; /* index of attr of interest in blk */ 186 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */ 187 int rmtblkcnt; /* remote attr value block count */ 188 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */ 189 int index2; /* index of 2nd attr in blk */ 190 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */ 191 int rmtblkcnt2; /* remote attr value block count */ 192 unsigned char justcheck; /* T/F: check for ok with no space */ 193 unsigned char rename; /* T/F: this is an atomic rename op */ 194 unsigned char addname; /* T/F: this is an add operation */ 195 unsigned char oknoent; /* T/F: ok to return ENOENT, else die */ 196 } xfs_da_args_t; 197 198 /* 199 * Structure to describe buffer(s) for a block. 200 * This is needed in the directory version 2 format case, when 201 * multiple non-contiguous fsblocks might be needed to cover one 202 * logical directory block. 203 * If the buffer count is 1 then the data pointer points to the 204 * same place as the b_addr field for the buffer, else to kmem_alloced memory. 205 */ 206 typedef struct xfs_dabuf { 207 int nbuf; /* number of buffer pointers present */ 208 short dirty; /* data needs to be copied back */ 209 short bbcount; /* how large is data in bbs */ 210 void *data; /* pointer for buffers' data */ 211 #ifdef XFS_DABUF_DEBUG 212 inst_t *ra; /* return address of caller to make */ 213 struct xfs_dabuf *next; /* next in global chain */ 214 struct xfs_dabuf *prev; /* previous in global chain */ 215 struct xfs_buftarg *target; /* device for buffer */ 216 xfs_daddr_t blkno; /* daddr first in bps[0] */ 217 #endif 218 struct xfs_buf *bps[1]; /* actually nbuf of these */ 219 } xfs_dabuf_t; 220 #define XFS_DA_BUF_SIZE(n) \ 221 (sizeof(xfs_dabuf_t) + sizeof(struct xfs_buf *) * ((n) - 1)) 222 223 #ifdef XFS_DABUF_DEBUG 224 extern xfs_dabuf_t *xfs_dabuf_global_list; 225 #endif 226 227 /* 228 * Storage for holding state during Btree searches and split/join ops. 229 * 230 * Only need space for 5 intermediate nodes. With a minimum of 62-way 231 * fanout to the Btree, we can support over 900 million directory blocks, 232 * which is slightly more than enough. 233 */ 234 typedef struct xfs_da_state_blk { 235 xfs_dabuf_t *bp; /* buffer containing block */ 236 xfs_dablk_t blkno; /* filesystem blkno of buffer */ 237 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */ 238 int index; /* relevant index into block */ 239 xfs_dahash_t hashval; /* last hash value in block */ 240 int magic; /* blk's magic number, ie: blk type */ 241 } xfs_da_state_blk_t; 242 243 typedef struct xfs_da_state_path { 244 int active; /* number of active levels */ 245 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH]; 246 } xfs_da_state_path_t; 247 248 typedef struct xfs_da_state { 249 xfs_da_args_t *args; /* filename arguments */ 250 struct xfs_mount *mp; /* filesystem mount point */ 251 unsigned int blocksize; /* logical block size */ 252 unsigned int node_ents; /* how many entries in danode */ 253 xfs_da_state_path_t path; /* search/split paths */ 254 xfs_da_state_path_t altpath; /* alternate path for join */ 255 unsigned char inleaf; /* insert into 1->lf, 0->splf */ 256 unsigned char extravalid; /* T/F: extrablk is in use */ 257 unsigned char extraafter; /* T/F: extrablk is after new */ 258 xfs_da_state_blk_t extrablk; /* for double-splits on leafs */ 259 /* for dirv2 extrablk is data */ 260 } xfs_da_state_t; 261 262 /* 263 * Utility macros to aid in logging changed structure fields. 264 */ 265 #define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE)) 266 #define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \ 267 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \ 268 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1) 269 270 271 #ifdef __KERNEL__ 272 /*======================================================================== 273 * Function prototypes for the kernel. 274 *========================================================================*/ 275 276 /* 277 * Routines used for growing the Btree. 278 */ 279 int xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level, 280 xfs_dabuf_t **bpp, int whichfork); 281 int xfs_da_split(xfs_da_state_t *state); 282 283 /* 284 * Routines used for shrinking the Btree. 285 */ 286 int xfs_da_join(xfs_da_state_t *state); 287 void xfs_da_fixhashpath(xfs_da_state_t *state, 288 xfs_da_state_path_t *path_to_to_fix); 289 290 /* 291 * Routines used for finding things in the Btree. 292 */ 293 int xfs_da_node_lookup_int(xfs_da_state_t *state, int *result); 294 int xfs_da_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path, 295 int forward, int release, int *result); 296 /* 297 * Utility routines. 298 */ 299 int xfs_da_blk_unlink(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk, 300 xfs_da_state_blk_t *save_blk); 301 int xfs_da_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk, 302 xfs_da_state_blk_t *new_blk); 303 304 /* 305 * Utility routines. 306 */ 307 int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno); 308 int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp, 309 xfs_dablk_t bno, xfs_daddr_t mappedbno, 310 xfs_dabuf_t **bp, int whichfork); 311 int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp, 312 xfs_dablk_t bno, xfs_daddr_t mappedbno, 313 xfs_dabuf_t **bpp, int whichfork); 314 xfs_daddr_t xfs_da_reada_buf(struct xfs_trans *trans, struct xfs_inode *dp, 315 xfs_dablk_t bno, int whichfork); 316 int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno, 317 xfs_dabuf_t *dead_buf); 318 319 uint xfs_da_hashname(uchar_t *name_string, int name_length); 320 uint xfs_da_log2_roundup(uint i); 321 xfs_da_state_t *xfs_da_state_alloc(void); 322 void xfs_da_state_free(xfs_da_state_t *state); 323 void xfs_da_state_kill_altpath(xfs_da_state_t *state); 324 325 void xfs_da_buf_done(xfs_dabuf_t *dabuf); 326 void xfs_da_log_buf(struct xfs_trans *tp, xfs_dabuf_t *dabuf, uint first, 327 uint last); 328 void xfs_da_brelse(struct xfs_trans *tp, xfs_dabuf_t *dabuf); 329 void xfs_da_binval(struct xfs_trans *tp, xfs_dabuf_t *dabuf); 330 xfs_daddr_t xfs_da_blkno(xfs_dabuf_t *dabuf); 331 332 extern struct kmem_zone *xfs_da_state_zone; 333 #endif /* __KERNEL__ */ 334 335 #endif /* __XFS_DA_BTREE_H__ */ 336