xref: /openbmc/linux/fs/jfs/jfs_xtree.h (revision 588b48ca)
1 /*
2  *   Copyright (C) International Business Machines Corp., 2000-2002
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_XTREE
19 #define _H_JFS_XTREE
20 
21 /*
22  *	jfs_xtree.h: extent allocation descriptor B+-tree manager
23  */
24 
25 #include "jfs_btree.h"
26 
27 
28 /*
29  *	extent allocation descriptor (xad)
30  */
31 typedef struct xad {
32 	unsigned flag:8;	/* 1: flag */
33 	unsigned rsvrd:16;	/* 2: reserved */
34 	unsigned off1:8;	/* 1: offset in unit of fsblksize */
35 	__le32 off2;		/* 4: offset in unit of fsblksize */
36 	unsigned len:24;	/* 3: length in unit of fsblksize */
37 	unsigned addr1:8;	/* 1: address in unit of fsblksize */
38 	__le32 addr2;		/* 4: address in unit of fsblksize */
39 } xad_t;			/* (16) */
40 
41 #define MAXXLEN		((1 << 24) - 1)
42 
43 #define XTSLOTSIZE	16
44 #define L2XTSLOTSIZE	4
45 
46 /* xad_t field construction */
47 #define XADoffset(xad, offset64)\
48 {\
49 	(xad)->off1 = ((u64)offset64) >> 32;\
50 	(xad)->off2 = __cpu_to_le32((offset64) & 0xffffffff);\
51 }
52 #define XADaddress(xad, address64)\
53 {\
54 	(xad)->addr1 = ((u64)address64) >> 32;\
55 	(xad)->addr2 = __cpu_to_le32((address64) & 0xffffffff);\
56 }
57 #define XADlength(xad, length32)	(xad)->len = __cpu_to_le24(length32)
58 
59 /* xad_t field extraction */
60 #define offsetXAD(xad)\
61 	( ((s64)((xad)->off1)) << 32 | __le32_to_cpu((xad)->off2))
62 #define addressXAD(xad)\
63 	( ((s64)((xad)->addr1)) << 32 | __le32_to_cpu((xad)->addr2))
64 #define lengthXAD(xad)	__le24_to_cpu((xad)->len)
65 
66 /* xad list */
67 struct xadlist {
68 	s16 maxnxad;
69 	s16 nxad;
70 	xad_t *xad;
71 };
72 
73 /* xad_t flags */
74 #define XAD_NEW		0x01	/* new */
75 #define XAD_EXTENDED	0x02	/* extended */
76 #define XAD_COMPRESSED	0x04	/* compressed with recorded length */
77 #define XAD_NOTRECORDED 0x08	/* allocated but not recorded */
78 #define XAD_COW		0x10	/* copy-on-write */
79 
80 
81 /* possible values for maxentry */
82 #define XTROOTINITSLOT_DIR 6
83 #define XTROOTINITSLOT	10
84 #define XTROOTMAXSLOT	18
85 #define XTPAGEMAXSLOT	256
86 #define XTENTRYSTART	2
87 
88 /*
89  *	xtree page:
90  */
91 typedef union {
92 	struct xtheader {
93 		__le64 next;	/* 8: */
94 		__le64 prev;	/* 8: */
95 
96 		u8 flag;	/* 1: */
97 		u8 rsrvd1;	/* 1: */
98 		__le16 nextindex;	/* 2: next index = number of entries */
99 		__le16 maxentry;	/* 2: max number of entries */
100 		__le16 rsrvd2;	/* 2: */
101 
102 		pxd_t self;	/* 8: self */
103 	} header;		/* (32) */
104 
105 	xad_t xad[XTROOTMAXSLOT];	/* 16 * maxentry: xad array */
106 } xtpage_t;
107 
108 /*
109  *	external declaration
110  */
111 extern int xtLookup(struct inode *ip, s64 lstart, s64 llen,
112 		    int *pflag, s64 * paddr, int *plen, int flag);
113 extern void xtInitRoot(tid_t tid, struct inode *ip);
114 extern int xtInsert(tid_t tid, struct inode *ip,
115 		    int xflag, s64 xoff, int xlen, s64 * xaddrp, int flag);
116 extern int xtExtend(tid_t tid, struct inode *ip, s64 xoff, int xlen,
117 		    int flag);
118 #ifdef _NOTYET
119 extern int xtTailgate(tid_t tid, struct inode *ip,
120 		      s64 xoff, int xlen, s64 xaddr, int flag);
121 #endif
122 extern int xtUpdate(tid_t tid, struct inode *ip, struct xad *nxad);
123 extern int xtDelete(tid_t tid, struct inode *ip, s64 xoff, int xlen,
124 		    int flag);
125 extern s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int type);
126 extern s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size);
127 extern int xtRelocate(tid_t tid, struct inode *ip,
128 		      xad_t * oxad, s64 nxaddr, int xtype);
129 extern int xtAppend(tid_t tid,
130 		    struct inode *ip, int xflag, s64 xoff, int maxblocks,
131 		    int *xlenp, s64 * xaddrp, int flag);
132 #endif				/* !_H_JFS_XTREE */
133