1 /* 2 * Copyright (C) International Business Machines Corp., 2000-2004 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 12 * the 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 to the Free Software 16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 17 */ 18 #ifndef _H_JFS_BTREE 19 #define _H_JFS_BTREE 20 21 /* 22 * jfs_btree.h: B+-tree 23 * 24 * JFS B+-tree (dtree and xtree) common definitions 25 */ 26 27 /* 28 * basic btree page - btpage 29 * 30 struct btpage { 31 s64 next; right sibling bn 32 s64 prev; left sibling bn 33 34 u8 flag; 35 u8 rsrvd[7]; type specific 36 s64 self; self address 37 38 u8 entry[4064]; 39 }; */ 40 41 /* btpaget_t flag */ 42 #define BT_TYPE 0x07 /* B+-tree index */ 43 #define BT_ROOT 0x01 /* root page */ 44 #define BT_LEAF 0x02 /* leaf page */ 45 #define BT_INTERNAL 0x04 /* internal page */ 46 #define BT_RIGHTMOST 0x10 /* rightmost page */ 47 #define BT_LEFTMOST 0x20 /* leftmost page */ 48 #define BT_SWAPPED 0x80 /* used by fsck for endian swapping */ 49 50 /* btorder (in inode) */ 51 #define BT_RANDOM 0x0000 52 #define BT_SEQUENTIAL 0x0001 53 #define BT_LOOKUP 0x0010 54 #define BT_INSERT 0x0020 55 #define BT_DELETE 0x0040 56 57 /* 58 * btree page buffer cache access 59 */ 60 #define BT_IS_ROOT(MP) (((MP)->xflag & COMMIT_PAGE) == 0) 61 62 /* get page from buffer page */ 63 #define BT_PAGE(IP, MP, TYPE, ROOT)\ 64 (BT_IS_ROOT(MP) ? (TYPE *)&JFS_IP(IP)->ROOT : (TYPE *)(MP)->data) 65 66 /* get the page buffer and the page for specified block address */ 67 #define BT_GETPAGE(IP, BN, MP, TYPE, SIZE, P, RC, ROOT)\ 68 {\ 69 if ((BN) == 0)\ 70 {\ 71 MP = (struct metapage *)&JFS_IP(IP)->bxflag;\ 72 P = (TYPE *)&JFS_IP(IP)->ROOT;\ 73 RC = 0;\ 74 }\ 75 else\ 76 {\ 77 MP = read_metapage((IP), BN, SIZE, 1);\ 78 if (MP) {\ 79 RC = 0;\ 80 P = (MP)->data;\ 81 } else {\ 82 P = NULL;\ 83 jfs_err("bread failed!");\ 84 RC = -EIO;\ 85 }\ 86 }\ 87 } 88 89 #define BT_MARK_DIRTY(MP, IP)\ 90 {\ 91 if (BT_IS_ROOT(MP))\ 92 mark_inode_dirty(IP);\ 93 else\ 94 mark_metapage_dirty(MP);\ 95 } 96 97 /* put the page buffer */ 98 #define BT_PUTPAGE(MP)\ 99 {\ 100 if (! BT_IS_ROOT(MP)) \ 101 release_metapage(MP); \ 102 } 103 104 105 /* 106 * btree traversal stack 107 * 108 * record the path traversed during the search; 109 * top frame record the leaf page/entry selected. 110 */ 111 struct btframe { /* stack frame */ 112 s64 bn; /* 8: */ 113 s16 index; /* 2: */ 114 s16 lastindex; /* 2: unused */ 115 struct metapage *mp; /* 4/8: */ 116 }; /* (16/24) */ 117 118 struct btstack { 119 struct btframe *top; 120 int nsplit; 121 struct btframe stack[MAXTREEHEIGHT]; 122 }; 123 124 #define BT_CLR(btstack)\ 125 (btstack)->top = (btstack)->stack 126 127 #define BT_STACK_FULL(btstack)\ 128 ( (btstack)->top == &((btstack)->stack[MAXTREEHEIGHT-1])) 129 130 #define BT_PUSH(BTSTACK, BN, INDEX)\ 131 {\ 132 assert(!BT_STACK_FULL(BTSTACK));\ 133 (BTSTACK)->top->bn = BN;\ 134 (BTSTACK)->top->index = INDEX;\ 135 ++(BTSTACK)->top;\ 136 } 137 138 #define BT_POP(btstack)\ 139 ( (btstack)->top == (btstack)->stack ? NULL : --(btstack)->top ) 140 141 #define BT_STACK(btstack)\ 142 ( (btstack)->top == (btstack)->stack ? NULL : (btstack)->top ) 143 144 static inline void BT_STACK_DUMP(struct btstack *btstack) 145 { 146 int i; 147 printk("btstack dump:\n"); 148 for (i = 0; i < MAXTREEHEIGHT; i++) 149 printk(KERN_ERR "bn = %Lx, index = %d\n", 150 (long long)btstack->stack[i].bn, 151 btstack->stack[i].index); 152 } 153 154 /* retrieve search results */ 155 #define BT_GETSEARCH(IP, LEAF, BN, MP, TYPE, P, INDEX, ROOT)\ 156 {\ 157 BN = (LEAF)->bn;\ 158 MP = (LEAF)->mp;\ 159 if (BN)\ 160 P = (TYPE *)MP->data;\ 161 else\ 162 P = (TYPE *)&JFS_IP(IP)->ROOT;\ 163 INDEX = (LEAF)->index;\ 164 } 165 166 /* put the page buffer of search */ 167 #define BT_PUTSEARCH(BTSTACK)\ 168 {\ 169 if (! BT_IS_ROOT((BTSTACK)->top->mp))\ 170 release_metapage((BTSTACK)->top->mp);\ 171 } 172 #endif /* _H_JFS_BTREE */ 173