1/* 2 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc. 3 * All Rights Reserved. 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it would be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18#ifndef __XFS_DA_BTREE_H__ 19#define __XFS_DA_BTREE_H__ 20 21struct xfs_buf; 22struct xfs_bmap_free; 23struct xfs_inode; 24struct xfs_mount; 25struct xfs_trans; 26struct zone; 27 28/*======================================================================== 29 * Directory Structure when greater than XFS_LBSIZE(mp) bytes. 30 *========================================================================*/ 31 32/* 33 * This structure is common to both leaf nodes and non-leaf nodes in the Btree. 34 * 35 * Is is used to manage a doubly linked list of all blocks at the same 36 * level in the Btree, and to identify which type of block this is. 37 */ 38#define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */ 39#define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */ 40#define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */ 41#define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */ 42 43typedef struct xfs_da_blkinfo { 44 __be32 forw; /* previous block in list */ 45 __be32 back; /* following block in list */ 46 __be16 magic; /* validity check on block */ 47 __be16 pad; /* unused */ 48} xfs_da_blkinfo_t; 49 50/* 51 * This is the structure of the root and intermediate nodes in the Btree. 52 * The leaf nodes are defined above. 53 * 54 * Entries are not packed. 55 * 56 * Since we have duplicate keys, use a binary search but always follow 57 * all match in the block, not just the first match found. 58 */ 59#define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */ 60 61typedef struct xfs_da_intnode { 62 struct xfs_da_node_hdr { /* constant-structure header block */ 63 xfs_da_blkinfo_t info; /* block type, links, etc. */ 64 __be16 count; /* count of active entries */ 65 __be16 level; /* level above leaves (leaf == 0) */ 66 } hdr; 67 struct xfs_da_node_entry { 68 __be32 hashval; /* hash value for this descendant */ 69 __be32 before; /* Btree block before this key */ 70 } btree[1]; /* variable sized array of keys */ 71} xfs_da_intnode_t; 72typedef struct xfs_da_node_hdr xfs_da_node_hdr_t; 73typedef struct xfs_da_node_entry xfs_da_node_entry_t; 74 75#define XFS_DA_MAXHASH ((xfs_dahash_t)-1) /* largest valid hash value */ 76 77#define XFS_LBSIZE(mp) (mp)->m_sb.sb_blocksize 78#define XFS_LBLOG(mp) (mp)->m_sb.sb_blocklog 79 80#define XFS_DA_MAKE_BNOENTRY(mp,bno,entry) \ 81 (((bno) << (mp)->m_dircook_elog) | (entry)) 82#define XFS_DA_MAKE_COOKIE(mp,bno,entry,hash) \ 83 (((xfs_off_t)XFS_DA_MAKE_BNOENTRY(mp, bno, entry) << 32) | (hash)) 84#define XFS_DA_COOKIE_HASH(mp,cookie) ((xfs_dahash_t)cookie) 85#define XFS_DA_COOKIE_BNO(mp,cookie) \ 86 ((((xfs_off_t)(cookie) >> 31) == -1LL ? \ 87 (xfs_dablk_t)0 : \ 88 (xfs_dablk_t)((xfs_off_t)(cookie) >> \ 89 ((mp)->m_dircook_elog + 32)))) 90#define XFS_DA_COOKIE_ENTRY(mp,cookie) \ 91 ((((xfs_off_t)(cookie) >> 31) == -1LL ? \ 92 (xfs_dablk_t)0 : \ 93 (xfs_dablk_t)(((xfs_off_t)(cookie) >> 32) & \ 94 ((1 << (mp)->m_dircook_elog) - 1)))) 95 96 97/*======================================================================== 98 * Btree searching and modification structure definitions. 99 *========================================================================*/ 100 101/* 102 * Structure to ease passing around component names. 103 */ 104typedef struct xfs_da_args { 105 const uchar_t *name; /* string (maybe not NULL terminated) */ 106 int namelen; /* length of string (maybe no NULL) */ 107 uchar_t *value; /* set of bytes (maybe contain NULLs) */ 108 int valuelen; /* length of value */ 109 int flags; /* argument flags (eg: ATTR_NOCREATE) */ 110 xfs_dahash_t hashval; /* hash value of name */ 111 xfs_ino_t inumber; /* input/output inode number */ 112 struct xfs_inode *dp; /* directory inode to manipulate */ 113 xfs_fsblock_t *firstblock; /* ptr to firstblock for bmap calls */ 114 struct xfs_bmap_free *flist; /* ptr to freelist for bmap_finish */ 115 struct xfs_trans *trans; /* current trans (changes over time) */ 116 xfs_extlen_t total; /* total blocks needed, for 1st bmap */ 117 int whichfork; /* data or attribute fork */ 118 xfs_dablk_t blkno; /* blkno of attr leaf of interest */ 119 int index; /* index of attr of interest in blk */ 120 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */ 121 int rmtblkcnt; /* remote attr value block count */ 122 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */ 123 int index2; /* index of 2nd attr in blk */ 124 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */ 125 int rmtblkcnt2; /* remote attr value block count */ 126 unsigned char justcheck; /* T/F: check for ok with no space */ 127 unsigned char rename; /* T/F: this is an atomic rename op */ 128 unsigned char addname; /* T/F: this is an add operation */ 129 unsigned char oknoent; /* T/F: ok to return ENOENT, else die */ 130} xfs_da_args_t; 131 132/* 133 * Structure to describe buffer(s) for a block. 134 * This is needed in the directory version 2 format case, when 135 * multiple non-contiguous fsblocks might be needed to cover one 136 * logical directory block. 137 * If the buffer count is 1 then the data pointer points to the 138 * same place as the b_addr field for the buffer, else to kmem_alloced memory. 139 */ 140typedef struct xfs_dabuf { 141 int nbuf; /* number of buffer pointers present */ 142 short dirty; /* data needs to be copied back */ 143 short bbcount; /* how large is data in bbs */ 144 void *data; /* pointer for buffers' data */ 145#ifdef XFS_DABUF_DEBUG 146 inst_t *ra; /* return address of caller to make */ 147 struct xfs_dabuf *next; /* next in global chain */ 148 struct xfs_dabuf *prev; /* previous in global chain */ 149 struct xfs_buftarg *target; /* device for buffer */ 150 xfs_daddr_t blkno; /* daddr first in bps[0] */ 151#endif 152 struct xfs_buf *bps[1]; /* actually nbuf of these */ 153} xfs_dabuf_t; 154#define XFS_DA_BUF_SIZE(n) \ 155 (sizeof(xfs_dabuf_t) + sizeof(struct xfs_buf *) * ((n) - 1)) 156 157#ifdef XFS_DABUF_DEBUG 158extern xfs_dabuf_t *xfs_dabuf_global_list; 159#endif 160 161/* 162 * Storage for holding state during Btree searches and split/join ops. 163 * 164 * Only need space for 5 intermediate nodes. With a minimum of 62-way 165 * fanout to the Btree, we can support over 900 million directory blocks, 166 * which is slightly more than enough. 167 */ 168typedef struct xfs_da_state_blk { 169 xfs_dabuf_t *bp; /* buffer containing block */ 170 xfs_dablk_t blkno; /* filesystem blkno of buffer */ 171 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */ 172 int index; /* relevant index into block */ 173 xfs_dahash_t hashval; /* last hash value in block */ 174 int magic; /* blk's magic number, ie: blk type */ 175} xfs_da_state_blk_t; 176 177typedef struct xfs_da_state_path { 178 int active; /* number of active levels */ 179 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH]; 180} xfs_da_state_path_t; 181 182typedef struct xfs_da_state { 183 xfs_da_args_t *args; /* filename arguments */ 184 struct xfs_mount *mp; /* filesystem mount point */ 185 unsigned int blocksize; /* logical block size */ 186 unsigned int node_ents; /* how many entries in danode */ 187 xfs_da_state_path_t path; /* search/split paths */ 188 xfs_da_state_path_t altpath; /* alternate path for join */ 189 unsigned char inleaf; /* insert into 1->lf, 0->splf */ 190 unsigned char extravalid; /* T/F: extrablk is in use */ 191 unsigned char extraafter; /* T/F: extrablk is after new */ 192 xfs_da_state_blk_t extrablk; /* for double-splits on leafs */ 193 /* for dirv2 extrablk is data */ 194} xfs_da_state_t; 195 196/* 197 * Utility macros to aid in logging changed structure fields. 198 */ 199#define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE)) 200#define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \ 201 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \ 202 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1) 203 204 205#ifdef __KERNEL__ 206/*======================================================================== 207 * Function prototypes for the kernel. 208 *========================================================================*/ 209 210/* 211 * Routines used for growing the Btree. 212 */ 213int xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level, 214 xfs_dabuf_t **bpp, int whichfork); 215int xfs_da_split(xfs_da_state_t *state); 216 217/* 218 * Routines used for shrinking the Btree. 219 */ 220int xfs_da_join(xfs_da_state_t *state); 221void xfs_da_fixhashpath(xfs_da_state_t *state, 222 xfs_da_state_path_t *path_to_to_fix); 223 224/* 225 * Routines used for finding things in the Btree. 226 */ 227int xfs_da_node_lookup_int(xfs_da_state_t *state, int *result); 228int xfs_da_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path, 229 int forward, int release, int *result); 230/* 231 * Utility routines. 232 */ 233int xfs_da_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk, 234 xfs_da_state_blk_t *new_blk); 235 236/* 237 * Utility routines. 238 */ 239int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno); 240int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp, 241 xfs_dablk_t bno, xfs_daddr_t mappedbno, 242 xfs_dabuf_t **bp, int whichfork); 243int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp, 244 xfs_dablk_t bno, xfs_daddr_t mappedbno, 245 xfs_dabuf_t **bpp, int whichfork); 246xfs_daddr_t xfs_da_reada_buf(struct xfs_trans *trans, struct xfs_inode *dp, 247 xfs_dablk_t bno, int whichfork); 248int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno, 249 xfs_dabuf_t *dead_buf); 250 251uint xfs_da_hashname(const uchar_t *name_string, int name_length); 252xfs_da_state_t *xfs_da_state_alloc(void); 253void xfs_da_state_free(xfs_da_state_t *state); 254 255void xfs_da_buf_done(xfs_dabuf_t *dabuf); 256void xfs_da_log_buf(struct xfs_trans *tp, xfs_dabuf_t *dabuf, uint first, 257 uint last); 258void xfs_da_brelse(struct xfs_trans *tp, xfs_dabuf_t *dabuf); 259void xfs_da_binval(struct xfs_trans *tp, xfs_dabuf_t *dabuf); 260xfs_daddr_t xfs_da_blkno(xfs_dabuf_t *dabuf); 261 262extern struct kmem_zone *xfs_da_state_zone; 263#endif /* __KERNEL__ */ 264 265#endif /* __XFS_DA_BTREE_H__ */ 266