fs/jfs/jfs_xtree.h

   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 */