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        __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 */
  60struct 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 */
  84typedef 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 */
 104extern int xtLookup(struct inode *ip, s64 lstart, s64 llen,
 105                    int *pflag, s64 * paddr, int *plen, int flag);
 106extern void xtInitRoot(tid_t tid, struct inode *ip);
 107extern int xtInsert(tid_t tid, struct inode *ip,
 108                    int xflag, s64 xoff, int xlen, s64 * xaddrp, int flag);
 109extern int xtExtend(tid_t tid, struct inode *ip, s64 xoff, int xlen,
 110                    int flag);
 111#ifdef _NOTYET
 112extern int xtTailgate(tid_t tid, struct inode *ip,
 113                      s64 xoff, int xlen, s64 xaddr, int flag);
 114#endif
 115extern int xtUpdate(tid_t tid, struct inode *ip, struct xad *nxad);
 116extern int xtDelete(tid_t tid, struct inode *ip, s64 xoff, int xlen,
 117                    int flag);
 118extern s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int type);
 119extern s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size);
 120extern int xtRelocate(tid_t tid, struct inode *ip,
 121                      xad_t * oxad, s64 nxaddr, int xtype);
 122extern 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