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         __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 */