LXR linux/fs/jfs/jfs

   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 */
  31typedef 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 */
  67struct 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 */
  91typedef 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 */
 111extern int xtLookup(struct inode *ip, s64 lstart, s64 llen,
 112                    int *pflag, s64 * paddr, int *plen, int flag);
 113extern void xtInitRoot(tid_t tid, struct inode *ip);
 114extern int xtInsert(tid_t tid, struct inode *ip,
 115                    int xflag, s64 xoff, int xlen, s64 * xaddrp, int flag);
 116extern int xtExtend(tid_t tid, struct inode *ip, s64 xoff, int xlen,
 117                    int flag);
 118#ifdef _NOTYET
 119extern int xtTailgate(tid_t tid, struct inode *ip,
 120                      s64 xoff, int xlen, s64 xaddr, int flag);
 121#endif
 122extern int xtUpdate(tid_t tid, struct inode *ip, struct xad *nxad);
 123extern int xtDelete(tid_t tid, struct inode *ip, s64 xoff, int xlen,
 124                    int flag);
 125extern s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int type);
 126extern s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size);
 127extern int xtRelocate(tid_t tid, struct inode *ip,
 128                      xad_t * oxad, s64 nxaddr, int xtype);
 129extern 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