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 	__u8 flag;	/* 1: flag */
33 	__u8 rsvrd[2];	/* 2: reserved */
34 	__u8 off1;	/* 1: offset in unit of fsblksize */
35 	__le32 off2;	/* 4: offset in unit of fsblksize */
36 	pxd_t loc;	/* 8: length and address in unit of fsblksize */
37 } xad_t;			/* (16) */
38 
39 #define MAXXLEN		((1 << 24) - 1)
40 
41 #define XTSLOTSIZE	16
42 #define L2XTSLOTSIZE	4
43 
44 /* xad_t field construction */
45 #define XADoffset(xad, offset64)\
46 {\
47 	(xad)->off1 = ((u64)offset64) >> 32;\
48 	(xad)->off2 = __cpu_to_le32((offset64) & 0xffffffff);\
49 }
50 #define XADaddress(xad, address64) PXDaddress(&(xad)->loc, address64)
51 #define XADlength(xad, length32) PXDlength(&(xad)->loc, length32)
52 
53 /* xad_t field extraction */
54 #define offsetXAD(xad)\
55 	( ((s64)((xad)->off1)) << 32 | __le32_to_cpu((xad)->off2))
56 #define addressXAD(xad) addressPXD(&(xad)->loc)
57 #define lengthXAD(xad) lengthPXD(&(xad)->loc)
58 
59 /* xad list */
60 struct xadlist {
61 	s16 maxnxad;
62 	s16 nxad;
63 	xad_t *xad;
64 };
65 
66 /* xad_t flags */
67 #define XAD_NEW		0x01	/* new */
68 #define XAD_EXTENDED	0x02	/* extended */
69 #define XAD_COMPRESSED	0x04	/* compressed with recorded length */
70 #define XAD_NOTRECORDED 0x08	/* allocated but not recorded */
71 #define XAD_COW		0x10	/* copy-on-write */
72 
73 
74 /* possible values for maxentry */
75 #define XTROOTINITSLOT_DIR 6
76 #define XTROOTINITSLOT	10
77 #define XTROOTMAXSLOT	18
78 #define XTPAGEMAXSLOT	256
79 #define XTENTRYSTART	2
80 
81 /*
82  *	xtree page:
83  */
84 typedef union {
85 	struct xtheader {
86 		__le64 next;	/* 8: */
87 		__le64 prev;	/* 8: */
88 
89 		u8 flag;	/* 1: */
90 		u8 rsrvd1;	/* 1: */
91 		__le16 nextindex;	/* 2: next index = number of entries */
92 		__le16 maxentry;	/* 2: max number of entries */
93 		__le16 rsrvd2;	/* 2: */
94 
95 		pxd_t self;	/* 8: self */
96 	} header;		/* (32) */
97 
98 	xad_t xad[XTROOTMAXSLOT];	/* 16 * maxentry: xad array */
99 } xtpage_t;
100 
101 /*
102  *	external declaration
103  */
104 extern int xtLookup(struct inode *ip, s64 lstart, s64 llen,
105 		    int *pflag, s64 * paddr, int *plen, int flag);
106 extern void xtInitRoot(tid_t tid, struct inode *ip);
107 extern int xtInsert(tid_t tid, struct inode *ip,
108 		    int xflag, s64 xoff, int xlen, s64 * xaddrp, int flag);
109 extern int xtExtend(tid_t tid, struct inode *ip, s64 xoff, int xlen,
110 		    int flag);
111 #ifdef _NOTYET
112 extern int xtTailgate(tid_t tid, struct inode *ip,
113 		      s64 xoff, int xlen, s64 xaddr, int flag);
114 #endif
115 extern int xtUpdate(tid_t tid, struct inode *ip, struct xad *nxad);
116 extern int xtDelete(tid_t tid, struct inode *ip, s64 xoff, int xlen,
117 		    int flag);
118 extern s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int type);
119 extern s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size);
120 extern int xtRelocate(tid_t tid, struct inode *ip,
121 		      xad_t * oxad, s64 nxaddr, int xtype);
122 extern int xtAppend(tid_t tid,
123 		    struct inode *ip, int xflag, s64 xoff, int maxblocks,
124 		    int *xlenp, s64 * xaddrp, int flag);
125 #endif				/* !_H_JFS_XTREE */
126