fs/jfs/jfs_dmap.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_DMAP
  19 #define _H_JFS_DMAP
  20
  21 #include "jfs_txnmgr.h"
  22
  23 #define BMAPVERSION     1       /* version number */
  24 #define TREESIZE        (256+64+16+4+1) /* size of a dmap tree */
  25 #define LEAFIND         (64+16+4+1)     /* index of 1st leaf of a dmap tree */
  26 #define LPERDMAP        256     /* num leaves per dmap tree */
  27 #define L2LPERDMAP      8       /* l2 number of leaves per dmap tree */
  28 #define DBWORD          32      /* # of blks covered by a map word */
  29 #define L2DBWORD        5       /* l2 # of blks covered by a mword */
  30 #define BUDMIN          L2DBWORD        /* max free string in a map word */
  31 #define BPERDMAP        (LPERDMAP * DBWORD)     /* num of blks per dmap */
  32 #define L2BPERDMAP      13      /* l2 num of blks per dmap */
  33 #define CTLTREESIZE     (1024+256+64+16+4+1)    /* size of a dmapctl tree */
  34 #define CTLLEAFIND      (256+64+16+4+1) /* idx of 1st leaf of a dmapctl tree */
  35 #define LPERCTL         1024    /* num of leaves per dmapctl tree */
  36 #define L2LPERCTL       10      /* l2 num of leaves per dmapctl tree */
  37 #define ROOT            0       /* index of the root of a tree */
  38 #define NOFREE          ((s8) -1)       /* no blocks free */
  39 #define MAXAG           128     /* max number of allocation groups */
  40 #define L2MAXAG         7       /* l2 max num of AG */
  41 #define L2MINAGSZ       25      /* l2 of minimum AG size in bytes */
  42 #define BMAPBLKNO       0       /* lblkno of bmap within the map */
  43
  44 /*
  45  * maximum l2 number of disk blocks at the various dmapctl levels.
  46  */
  47 #define L2MAXL0SIZE     (L2BPERDMAP + 1 * L2LPERCTL)
  48 #define L2MAXL1SIZE     (L2BPERDMAP + 2 * L2LPERCTL)
  49 #define L2MAXL2SIZE     (L2BPERDMAP + 3 * L2LPERCTL)
  50
  51 /*
  52  * maximum number of disk blocks at the various dmapctl levels.
  53  */
  54 #define MAXL0SIZE       ((s64)1 << L2MAXL0SIZE)
  55 #define MAXL1SIZE       ((s64)1 << L2MAXL1SIZE)
  56 #define MAXL2SIZE       ((s64)1 << L2MAXL2SIZE)
  57
  58 #define MAXMAPSIZE      MAXL2SIZE       /* maximum aggregate map size */
  59
  60 /*
  61  * determine the maximum free string for four (lower level) nodes
  62  * of the tree.
  63  */
  64 static __inline signed char TREEMAX(signed char *cp)
  65 {
  66         signed char tmp1, tmp2;
  67
  68         tmp1 = max(*(cp+2), *(cp+3));
  69         tmp2 = max(*(cp), *(cp+1));
  70
  71         return max(tmp1, tmp2);
  72 }
  73
  74 /*
  75  * convert disk block number to the logical block number of the dmap
  76  * describing the disk block.  s is the log2(number of logical blocks per page)
  77  *
  78  * The calculation figures out how many logical pages are in front of the dmap.
  79  *      - the number of dmaps preceding it
  80  *      - the number of L0 pages preceding its L0 page
  81  *      - the number of L1 pages preceding its L1 page
  82  *      - 3 is added to account for the L2, L1, and L0 page for this dmap
  83  *      - 1 is added to account for the control page of the map.
  84  */
  85 #define BLKTODMAP(b,s)    \
  86         ((((b) >> 13) + ((b) >> 23) + ((b) >> 33) + 3 + 1) << (s))
  87
  88 /*
  89  * convert disk block number to the logical block number of the LEVEL 0
  90  * dmapctl describing the disk block.  s is the log2(number of logical blocks
  91  * per page)
  92  *
  93  * The calculation figures out how many logical pages are in front of the L0.
  94  *      - the number of dmap pages preceding it
  95  *      - the number of L0 pages preceding it
  96  *      - the number of L1 pages preceding its L1 page
  97  *      - 2 is added to account for the L2, and L1 page for this L0
  98  *      - 1 is added to account for the control page of the map.
  99  */
 100 #define BLKTOL0(b,s)      \
 101         (((((b) >> 23) << 10) + ((b) >> 23) + ((b) >> 33) + 2 + 1) << (s))
 102
 103 /*
 104  * convert disk block number to the logical block number of the LEVEL 1
 105  * dmapctl describing the disk block.  s is the log2(number of logical blocks
 106  * per page)
 107  *
 108  * The calculation figures out how many logical pages are in front of the L1.
 109  *      - the number of dmap pages preceding it
 110  *      - the number of L0 pages preceding it
 111  *      - the number of L1 pages preceding it
 112  *      - 1 is added to account for the L2 page
 113  *      - 1 is added to account for the control page of the map.
 114  */
 115 #define BLKTOL1(b,s)      \
 116      (((((b) >> 33) << 20) + (((b) >> 33) << 10) + ((b) >> 33) + 1 + 1) << (s))
 117
 118 /*
 119  * convert disk block number to the logical block number of the dmapctl
 120  * at the specified level which describes the disk block.
 121  */
 122 #define BLKTOCTL(b,s,l)   \
 123         (((l) == 2) ? 1 : ((l) == 1) ? BLKTOL1((b),(s)) : BLKTOL0((b),(s)))
 124
 125 /*
 126  * convert aggregate map size to the zero origin dmapctl level of the
 127  * top dmapctl.
 128  */
 129 #define BMAPSZTOLEV(size)       \
 130         (((size) <= MAXL0SIZE) ? 0 : ((size) <= MAXL1SIZE) ? 1 : 2)
 131
 132 /* convert disk block number to allocation group number.
 133  */
 134 #define BLKTOAG(b,sbi)  ((b) >> ((sbi)->bmap->db_agl2size))
 135
 136 /* convert allocation group number to starting disk block
 137  * number.
 138  */
 139 #define AGTOBLK(a,ip)   \
 140         ((s64)(a) << (JFS_SBI((ip)->i_sb)->bmap->db_agl2size))
 141
 142 /*
 143  *      dmap summary tree
 144  *
 145  * dmaptree must be consistent with dmapctl.
 146  */
 147 struct dmaptree {
 148         s32 nleafs;             /* 4: number of tree leafs      */
 149         s32 l2nleafs;           /* 4: l2 number of tree leafs   */
 150         s32 leafidx;            /* 4: index of first tree leaf  */
 151         s32 height;             /* 4: height of the tree        */
 152         s8 budmin;              /* 1: min l2 tree leaf value to combine */
 153         s8 stree[TREESIZE];     /* TREESIZE: tree               */
 154         u8 pad[2];              /* 2: pad to word boundary      */
 155 };                              /* - 360 -                      */
 156
 157 /*
 158  *      dmap page per 8K blocks bitmap
 159  */
 160 struct dmap {
 161         s32 nblocks;            /* 4: num blks covered by this dmap     */
 162         s32 nfree;              /* 4: num of free blks in this dmap     */
 163         s64 start;              /* 8: starting blkno for this dmap      */
 164         struct dmaptree tree;   /* 360: dmap tree                       */
 165         u8 pad[1672];           /* 1672: pad to 2048 bytes              */
 166         u32 wmap[LPERDMAP];     /* 1024: bits of the working map        */
 167         u32 pmap[LPERDMAP];     /* 1024: bits of the persistent map     */
 168 };                              /* - 4096 -                             */
 169
 170 /*
 171  *      disk map control page per level.
 172  *
 173  * dmapctl must be consistent with dmaptree.
 174  */
 175 struct dmapctl {
 176         s32 nleafs;             /* 4: number of tree leafs      */
 177         s32 l2nleafs;           /* 4: l2 number of tree leafs   */
 178         s32 leafidx;            /* 4: index of the first tree leaf      */
 179         s32 height;             /* 4: height of tree            */
 180         s8 budmin;              /* 1: minimum l2 tree leaf value        */
 181         s8 stree[CTLTREESIZE];  /* CTLTREESIZE: dmapctl tree    */
 182         u8 pad[2714];           /* 2714: pad to 4096            */
 183 };                              /* - 4096 -                     */
 184
 185 /*
 186  *      common definition for dmaptree within dmap and dmapctl
 187  */
 188 typedef union dmtree {
 189         struct dmaptree t1;
 190         struct dmapctl t2;
 191 } dmtree_t;
 192
 193 /* macros for accessing fields within dmtree */
 194 #define dmt_nleafs      t1.nleafs
 195 #define dmt_l2nleafs    t1.l2nleafs
 196 #define dmt_leafidx     t1.leafidx
 197 #define dmt_height      t1.height
 198 #define dmt_budmin      t1.budmin
 199 #define dmt_stree       t1.stree
 200
 201 /*
 202  *      on-disk aggregate disk allocation map descriptor.
 203  */
 204 struct dbmap {
 205         s64 dn_mapsize;         /* 8: number of blocks in aggregate     */
 206         s64 dn_nfree;           /* 8: num free blks in aggregate map    */
 207         s32 dn_l2nbperpage;     /* 4: number of blks per page           */
 208         s32 dn_numag;           /* 4: total number of ags               */
 209         s32 dn_maxlevel;        /* 4: number of active ags              */
 210         s32 dn_maxag;           /* 4: max active alloc group number     */
 211         s32 dn_agpref;          /* 4: preferred alloc group (hint)      */
 212         s32 dn_aglevel;         /* 4: dmapctl level holding the AG      */
 213         s32 dn_agheigth;        /* 4: height in dmapctl of the AG       */
 214         s32 dn_agwidth;         /* 4: width in dmapctl of the AG        */
 215         s32 dn_agstart;         /* 4: start tree index at AG height     */
 216         s32 dn_agl2size;        /* 4: l2 num of blks per alloc group    */
 217         s64 dn_agfree[MAXAG];   /* 8*MAXAG: per AG free count           */
 218         s64 dn_agsize;          /* 8: num of blks per alloc group       */
 219         s8 dn_maxfreebud;       /* 1: max free buddy system             */
 220         u8 pad[3007];           /* 3007: pad to 4096                    */
 221 };                              /* - 4096 -                             */
 222
 223 /*
 224  *      in-memory aggregate disk allocation map descriptor.
 225  */
 226 struct bmap {
 227         struct dbmap db_bmap;   /* on-disk aggregate map descriptor */
 228         struct inode *db_ipbmap;        /* ptr to aggregate map incore inode */
 229         struct semaphore db_bmaplock;   /* aggregate map lock */
 230         atomic_t db_active[MAXAG];      /* count of active, open files in AG */
 231         u32 *db_DBmap;
 232 };
 233
 234 /* macros for accessing fields within in-memory aggregate map descriptor */
 235 #define db_mapsize      db_bmap.dn_mapsize
 236 #define db_nfree        db_bmap.dn_nfree
 237 #define db_agfree       db_bmap.dn_agfree
 238 #define db_agsize       db_bmap.dn_agsize
 239 #define db_agl2size     db_bmap.dn_agl2size
 240 #define db_agwidth      db_bmap.dn_agwidth
 241 #define db_agheigth     db_bmap.dn_agheigth
 242 #define db_agstart      db_bmap.dn_agstart
 243 #define db_numag        db_bmap.dn_numag
 244 #define db_maxlevel     db_bmap.dn_maxlevel
 245 #define db_aglevel      db_bmap.dn_aglevel
 246 #define db_agpref       db_bmap.dn_agpref
 247 #define db_maxag        db_bmap.dn_maxag
 248 #define db_maxfreebud   db_bmap.dn_maxfreebud
 249 #define db_l2nbperpage  db_bmap.dn_l2nbperpage
 250
 251 /*
 252  * macros for various conversions needed by the allocators.
 253  * blkstol2(), cntlz(), and cnttz() are operating system dependent functions.
 254  */
 255 /* convert number of blocks to log2 number of blocks, rounding up to
 256  * the next log2 value if blocks is not a l2 multiple.
 257  */
 258 #define BLKSTOL2(d)             (blkstol2(d))
 259
 260 /* convert number of leafs to log2 leaf value */
 261 #define NLSTOL2BSZ(n)           (31 - cntlz((n)) + BUDMIN)
 262
 263 /* convert leaf index to log2 leaf value */
 264 #define LITOL2BSZ(n,m,b)        ((((n) == 0) ? (m) : cnttz((n))) + (b))
 265
 266 /* convert a block number to a dmap control leaf index */
 267 #define BLKTOCTLLEAF(b,m)       \
 268         (((b) & (((s64)1 << ((m) + L2LPERCTL)) - 1)) >> (m))
 269
 270 /* convert log2 leaf value to buddy size */
 271 #define BUDSIZE(s,m)            (1 << ((s) - (m)))
 272
 273 /*
 274  *      external references.
 275  */
 276 extern int dbMount(struct inode *ipbmap);
 277
 278 extern int dbUnmount(struct inode *ipbmap, int mounterror);
 279
 280 extern int dbFree(struct inode *ipbmap, s64 blkno, s64 nblocks);
 281
 282 extern int dbUpdatePMap(struct inode *ipbmap,
 283                         int free, s64 blkno, s64 nblocks, struct tblock * tblk);
 284
 285 extern int dbNextAG(struct inode *ipbmap);
 286
 287 extern int dbAlloc(struct inode *ipbmap, s64 hint, s64 nblocks, s64 * results);
 288
 289 extern int dbReAlloc(struct inode *ipbmap,
 290                      s64 blkno, s64 nblocks, s64 addnblocks, s64 * results);
 291
 292 extern int dbSync(struct inode *ipbmap);
 293 extern int dbAllocBottomUp(struct inode *ip, s64 blkno, s64 nblocks);
 294 extern int dbExtendFS(struct inode *ipbmap, s64 blkno, s64 nblocks);
 295 extern void dbFinalizeBmap(struct inode *ipbmap);
 296 extern s64 dbMapFileSizeToMapSize(struct inode *ipbmap);
 297 #endif                          /* _H_JFS_DMAP */