xref: /linux/fs/jfs/jfs_xtree.h (revision bf5802238dc181b1f7375d358af1d01cd72d1c11)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *   Copyright (C) International Business Machines Corp., 2000-2002
4  */
5 #ifndef _H_JFS_XTREE
6 #define _H_JFS_XTREE
7 
8 /*
9  *	jfs_xtree.h: extent allocation descriptor B+-tree manager
10  */
11 
12 #include "jfs_btree.h"
13 
14 
15 /*
16  *	extent allocation descriptor (xad)
17  */
18 typedef struct xad {
19 	__u8 flag;	/* 1: flag */
20 	__u8 rsvrd[2];	/* 2: reserved */
21 	__u8 off1;	/* 1: offset in unit of fsblksize */
22 	__le32 off2;	/* 4: offset in unit of fsblksize */
23 	pxd_t loc;	/* 8: length and address in unit of fsblksize */
24 } xad_t;			/* (16) */
25 
26 #define MAXXLEN		((1 << 24) - 1)
27 
28 #define XTSLOTSIZE	16
29 #define L2XTSLOTSIZE	4
30 
31 /* xad_t field construction */
32 #define XADoffset(xad, offset64)\
33 {\
34 	(xad)->off1 = ((u64)offset64) >> 32;\
35 	(xad)->off2 = __cpu_to_le32((offset64) & 0xffffffff);\
36 }
37 #define XADaddress(xad, address64) PXDaddress(&(xad)->loc, address64)
38 #define XADlength(xad, length32) PXDlength(&(xad)->loc, length32)
39 
40 /* xad_t field extraction */
41 #define offsetXAD(xad)\
42 	( ((s64)((xad)->off1)) << 32 | __le32_to_cpu((xad)->off2))
43 #define addressXAD(xad) addressPXD(&(xad)->loc)
44 #define lengthXAD(xad) lengthPXD(&(xad)->loc)
45 
46 /* xad list */
47 struct xadlist {
48 	s16 maxnxad;
49 	s16 nxad;
50 	xad_t *xad;
51 };
52 
53 /* xad_t flags */
54 #define XAD_NEW		0x01	/* new */
55 #define XAD_EXTENDED	0x02	/* extended */
56 #define XAD_COMPRESSED	0x04	/* compressed with recorded length */
57 #define XAD_NOTRECORDED 0x08	/* allocated but not recorded */
58 #define XAD_COW		0x10	/* copy-on-write */
59 
60 
61 /* possible values for maxentry */
62 #define XTROOTINITSLOT_DIR 6
63 #define XTROOTINITSLOT	10
64 #define XTROOTMAXSLOT	18
65 #define XTPAGEMAXSLOT	256
66 #define XTENTRYSTART	2
67 
68 struct xtheader {
69 	__le64 next;	/* 8: */
70 	__le64 prev;	/* 8: */
71 
72 	u8 flag;	/* 1: */
73 	u8 rsrvd1;	/* 1: */
74 	__le16 nextindex;	/* 2: next index = number of entries */
75 	__le16 maxentry;	/* 2: max number of entries */
76 	__le16 rsrvd2;	/* 2: */
77 
78 	pxd_t self;	/* 8: self */
79 };
80 
81 /*
82  *	xtree root (in inode):
83  */
84 typedef union {
85 	struct xtheader header;
86 	xad_t xad[XTROOTMAXSLOT];	/* 16 * maxentry: xad array */
87 } xtroot_t;
88 
89 /*
90  *	xtree page:
91  */
92 typedef union {
93 	struct xtheader header;
94 	xad_t xad[XTPAGEMAXSLOT];	/* 16 * maxentry: xad array */
95 } xtpage_t;
96 
97 /*
98  *	external declaration
99  */
100 extern int xtLookup(struct inode *ip, s64 lstart, s64 llen,
101 		    int *pflag, s64 * paddr, int *plen, int flag);
102 extern void xtInitRoot(tid_t tid, struct inode *ip);
103 extern int xtInsert(tid_t tid, struct inode *ip,
104 		    int xflag, s64 xoff, int xlen, s64 * xaddrp, int flag);
105 extern int xtExtend(tid_t tid, struct inode *ip, s64 xoff, int xlen,
106 		    int flag);
107 extern int xtUpdate(tid_t tid, struct inode *ip, struct xad *nxad);
108 extern s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int type);
109 extern s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size);
110 extern int xtAppend(tid_t tid,
111 		    struct inode *ip, int xflag, s64 xoff, int maxblocks,
112 		    int *xlenp, s64 * xaddrp, int flag);
113 #endif				/* !_H_JFS_XTREE */
114