1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * Copyright (C) International Business Machines Corp., 2000-2004 4 */ 5 #ifndef _H_JFS_BTREE 6 #define _H_JFS_BTREE 7 8 /* 9 * jfs_btree.h: B+-tree 10 * 11 * JFS B+-tree (dtree and xtree) common definitions 12 */ 13 14 /* 15 * basic btree page - btpage 16 * 17 struct btpage { 18 s64 next; right sibling bn 19 s64 prev; left sibling bn 20 21 u8 flag; 22 u8 rsrvd[7]; type specific 23 s64 self; self address 24 25 u8 entry[4064]; 26 }; */ 27 28 /* btpaget_t flag */ 29 #define BT_TYPE 0x07 /* B+-tree index */ 30 #define BT_ROOT 0x01 /* root page */ 31 #define BT_LEAF 0x02 /* leaf page */ 32 #define BT_INTERNAL 0x04 /* internal page */ 33 #define BT_RIGHTMOST 0x10 /* rightmost page */ 34 #define BT_LEFTMOST 0x20 /* leftmost page */ 35 #define BT_SWAPPED 0x80 /* used by fsck for endian swapping */ 36 37 /* btorder (in inode) */ 38 #define BT_RANDOM 0x0000 39 #define BT_SEQUENTIAL 0x0001 40 #define BT_LOOKUP 0x0010 41 #define BT_INSERT 0x0020 42 #define BT_DELETE 0x0040 43 44 /* 45 * btree page buffer cache access 46 */ 47 #define BT_IS_ROOT(MP) (((MP)->xflag & COMMIT_PAGE) == 0) 48 49 /* get page from buffer page */ 50 #define BT_PAGE(IP, MP, TYPE, ROOT)\ 51 (BT_IS_ROOT(MP) ? (TYPE *)&JFS_IP(IP)->ROOT : (TYPE *)(MP)->data) 52 53 /* get the page buffer and the page for specified block address */ 54 #define BT_GETPAGE(IP, BN, MP, TYPE, SIZE, P, RC, ROOT)\ 55 {\ 56 if ((BN) == 0)\ 57 {\ 58 MP = (struct metapage *)&JFS_IP(IP)->bxflag;\ 59 P = (TYPE *)&JFS_IP(IP)->ROOT;\ 60 RC = 0;\ 61 }\ 62 else\ 63 {\ 64 MP = read_metapage((IP), BN, SIZE, 1);\ 65 if (MP) {\ 66 RC = 0;\ 67 P = (MP)->data;\ 68 } else {\ 69 P = NULL;\ 70 jfs_err("bread failed!");\ 71 RC = -EIO;\ 72 }\ 73 }\ 74 } 75 76 #define BT_MARK_DIRTY(MP, IP)\ 77 {\ 78 if (BT_IS_ROOT(MP))\ 79 mark_inode_dirty(IP);\ 80 else\ 81 mark_metapage_dirty(MP);\ 82 } 83 84 /* put the page buffer */ 85 #define BT_PUTPAGE(MP)\ 86 {\ 87 if (! BT_IS_ROOT(MP)) \ 88 release_metapage(MP); \ 89 } 90 91 92 /* 93 * btree traversal stack 94 * 95 * record the path traversed during the search; 96 * top frame record the leaf page/entry selected. 97 */ 98 struct btframe { /* stack frame */ 99 s64 bn; /* 8: */ 100 s16 index; /* 2: */ 101 s16 lastindex; /* 2: unused */ 102 struct metapage *mp; /* 4/8: */ 103 }; /* (16/24) */ 104 105 struct btstack { 106 struct btframe *top; 107 int nsplit; 108 struct btframe stack[MAXTREEHEIGHT]; 109 }; 110 111 #define BT_CLR(btstack)\ 112 (btstack)->top = (btstack)->stack 113 114 #define BT_STACK_FULL(btstack)\ 115 ( (btstack)->top == &((btstack)->stack[MAXTREEHEIGHT-1])) 116 117 #define BT_PUSH(BTSTACK, BN, INDEX)\ 118 {\ 119 assert(!BT_STACK_FULL(BTSTACK));\ 120 (BTSTACK)->top->bn = BN;\ 121 (BTSTACK)->top->index = INDEX;\ 122 ++(BTSTACK)->top;\ 123 } 124 125 #define BT_POP(btstack)\ 126 ( (btstack)->top == (btstack)->stack ? NULL : --(btstack)->top ) 127 128 #define BT_STACK(btstack)\ 129 ( (btstack)->top == (btstack)->stack ? NULL : (btstack)->top ) 130 131 static inline void BT_STACK_DUMP(struct btstack *btstack) 132 { 133 int i; 134 printk("btstack dump:\n"); 135 for (i = 0; i < MAXTREEHEIGHT; i++) 136 printk(KERN_ERR "bn = %Lx, index = %d\n", 137 (long long)btstack->stack[i].bn, 138 btstack->stack[i].index); 139 } 140 141 /* retrieve search results */ 142 #define BT_GETSEARCH(IP, LEAF, BN, MP, TYPE, P, INDEX, ROOT)\ 143 {\ 144 BN = (LEAF)->bn;\ 145 MP = (LEAF)->mp;\ 146 if (BN)\ 147 P = (TYPE *)MP->data;\ 148 else\ 149 P = (TYPE *)&JFS_IP(IP)->ROOT;\ 150 INDEX = (LEAF)->index;\ 151 } 152 153 /* put the page buffer of search */ 154 #define BT_PUTSEARCH(BTSTACK)\ 155 {\ 156 if (! BT_IS_ROOT((BTSTACK)->top->mp))\ 157 release_metapage((BTSTACK)->top->mp);\ 158 } 159 #endif /* _H_JFS_BTREE */ 160