fs/xfs/xfs_bmap_btree.h

   1 /*
   2  * Copyright (c) 2000,2002-2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * 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 the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #ifndef __XFS_BMAP_BTREE_H__
  19 #define __XFS_BMAP_BTREE_H__
  20
  21 #define XFS_BMAP_MAGIC  0x424d4150      /* 'BMAP' */
  22
  23 struct xfs_btree_cur;
  24 struct xfs_btree_block;
  25 struct xfs_mount;
  26 struct xfs_inode;
  27 struct xfs_trans;
  28
  29 /*
  30  * Bmap root header, on-disk form only.
  31  */
  32 typedef struct xfs_bmdr_block {
  33         __be16          bb_level;       /* 0 is a leaf */
  34         __be16          bb_numrecs;     /* current # of data records */
  35 } xfs_bmdr_block_t;
  36
  37 /*
  38  * Bmap btree record and extent descriptor.
  39  *  l0:63 is an extent flag (value 1 indicates non-normal).
  40  *  l0:9-62 are startoff.
  41  *  l0:0-8 and l1:21-63 are startblock.
  42  *  l1:0-20 are blockcount.
  43  */
  44 #define BMBT_EXNTFLAG_BITLEN    1
  45 #define BMBT_STARTOFF_BITLEN    54
  46 #define BMBT_STARTBLOCK_BITLEN  52
  47 #define BMBT_BLOCKCOUNT_BITLEN  21
  48
  49
  50 #define BMBT_USE_64     1
  51
  52 typedef struct xfs_bmbt_rec_32
  53 {
  54         __uint32_t              l0, l1, l2, l3;
  55 } xfs_bmbt_rec_32_t;
  56 typedef struct xfs_bmbt_rec_64
  57 {
  58         __be64                  l0, l1;
  59 } xfs_bmbt_rec_64_t;
  60
  61 typedef __uint64_t      xfs_bmbt_rec_base_t;    /* use this for casts */
  62 typedef xfs_bmbt_rec_64_t xfs_bmbt_rec_t, xfs_bmdr_rec_t;
  63
  64 typedef struct xfs_bmbt_rec_host {
  65         __uint64_t              l0, l1;
  66 } xfs_bmbt_rec_host_t;
  67
  68 /*
  69  * Values and macros for delayed-allocation startblock fields.
  70  */
  71 #define STARTBLOCKVALBITS       17
  72 #define STARTBLOCKMASKBITS      (15 + XFS_BIG_BLKNOS * 20)
  73 #define DSTARTBLOCKMASKBITS     (15 + 20)
  74 #define STARTBLOCKMASK          \
  75         (((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
  76 #define DSTARTBLOCKMASK         \
  77         (((((xfs_dfsbno_t)1) << DSTARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
  78
  79 static inline int isnullstartblock(xfs_fsblock_t x)
  80 {
  81         return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
  82 }
  83
  84 static inline int isnulldstartblock(xfs_dfsbno_t x)
  85 {
  86         return ((x) & DSTARTBLOCKMASK) == DSTARTBLOCKMASK;
  87 }
  88
  89 static inline xfs_fsblock_t nullstartblock(int k)
  90 {
  91         ASSERT(k < (1 << STARTBLOCKVALBITS));
  92         return STARTBLOCKMASK | (k);
  93 }
  94
  95 static inline xfs_filblks_t startblockval(xfs_fsblock_t x)
  96 {
  97         return (xfs_filblks_t)((x) & ~STARTBLOCKMASK);
  98 }
  99
 100 /*
 101  * Possible extent formats.
 102  */
 103 typedef enum {
 104         XFS_EXTFMT_NOSTATE = 0,
 105         XFS_EXTFMT_HASSTATE
 106 } xfs_exntfmt_t;
 107
 108 /*
 109  * Possible extent states.
 110  */
 111 typedef enum {
 112         XFS_EXT_NORM, XFS_EXT_UNWRITTEN,
 113         XFS_EXT_DMAPI_OFFLINE, XFS_EXT_INVALID
 114 } xfs_exntst_t;
 115
 116 /*
 117  * Extent state and extent format macros.
 118  */
 119 #define XFS_EXTFMT_INODE(x)     \
 120         (xfs_sb_version_hasextflgbit(&((x)->i_mount->m_sb)) ? \
 121                 XFS_EXTFMT_HASSTATE : XFS_EXTFMT_NOSTATE)
 122 #define ISUNWRITTEN(x)  ((x)->br_state == XFS_EXT_UNWRITTEN)
 123
 124 /*
 125  * Incore version of above.
 126  */
 127 typedef struct xfs_bmbt_irec
 128 {
 129         xfs_fileoff_t   br_startoff;    /* starting file offset */
 130         xfs_fsblock_t   br_startblock;  /* starting block number */
 131         xfs_filblks_t   br_blockcount;  /* number of blocks */
 132         xfs_exntst_t    br_state;       /* extent state */
 133 } xfs_bmbt_irec_t;
 134
 135 /*
 136  * Key structure for non-leaf levels of the tree.
 137  */
 138 typedef struct xfs_bmbt_key {
 139         __be64          br_startoff;    /* starting file offset */
 140 } xfs_bmbt_key_t, xfs_bmdr_key_t;
 141
 142 /* btree pointer type */
 143 typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
 144
 145 /*
 146  * Btree block header size depends on a superblock flag.
 147  *
 148  * (not quite yet, but soon)
 149  */
 150 #define XFS_BMBT_BLOCK_LEN(mp)  XFS_BTREE_LBLOCK_LEN
 151
 152 #define XFS_BMBT_REC_ADDR(mp, block, index) \
 153         ((xfs_bmbt_rec_t *) \
 154                 ((char *)(block) + \
 155                  XFS_BMBT_BLOCK_LEN(mp) + \
 156                  ((index) - 1) * sizeof(xfs_bmbt_rec_t)))
 157
 158 #define XFS_BMBT_KEY_ADDR(mp, block, index) \
 159         ((xfs_bmbt_key_t *) \
 160                 ((char *)(block) + \
 161                  XFS_BMBT_BLOCK_LEN(mp) + \
 162                  ((index) - 1) * sizeof(xfs_bmbt_key_t)))
 163
 164 #define XFS_BMBT_PTR_ADDR(mp, block, index, maxrecs) \
 165         ((xfs_bmbt_ptr_t *) \
 166                 ((char *)(block) + \
 167                  XFS_BMBT_BLOCK_LEN(mp) + \
 168                  (maxrecs) * sizeof(xfs_bmbt_key_t) + \
 169                  ((index) - 1) * sizeof(xfs_bmbt_ptr_t)))
 170
 171 #define XFS_BMDR_REC_ADDR(block, index) \
 172         ((xfs_bmdr_rec_t *) \
 173                 ((char *)(block) + \
 174                  sizeof(struct xfs_bmdr_block) + \
 175                  ((index) - 1) * sizeof(xfs_bmdr_rec_t)))
 176
 177 #define XFS_BMDR_KEY_ADDR(block, index) \
 178         ((xfs_bmdr_key_t *) \
 179                 ((char *)(block) + \
 180                  sizeof(struct xfs_bmdr_block) + \
 181                  ((index) - 1) * sizeof(xfs_bmdr_key_t)))
 182
 183 #define XFS_BMDR_PTR_ADDR(block, index, maxrecs) \
 184         ((xfs_bmdr_ptr_t *) \
 185                 ((char *)(block) + \
 186                  sizeof(struct xfs_bmdr_block) + \
 187                  (maxrecs) * sizeof(xfs_bmdr_key_t) + \
 188                  ((index) - 1) * sizeof(xfs_bmdr_ptr_t)))
 189
 190 /*
 191  * These are to be used when we know the size of the block and
 192  * we don't have a cursor.
 193  */
 194 #define XFS_BMAP_BROOT_PTR_ADDR(mp, bb, i, sz) \
 195         XFS_BMBT_PTR_ADDR(mp, bb, i, xfs_bmbt_maxrecs(mp, sz, 0))
 196
 197 #define XFS_BMAP_BROOT_SPACE_CALC(nrecs) \
 198         (int)(XFS_BTREE_LBLOCK_LEN + \
 199                ((nrecs) * (sizeof(xfs_bmbt_key_t) + sizeof(xfs_bmbt_ptr_t))))
 200
 201 #define XFS_BMAP_BROOT_SPACE(bb) \
 202         (XFS_BMAP_BROOT_SPACE_CALC(be16_to_cpu((bb)->bb_numrecs)))
 203 #define XFS_BMDR_SPACE_CALC(nrecs) \
 204         (int)(sizeof(xfs_bmdr_block_t) + \
 205                ((nrecs) * (sizeof(xfs_bmbt_key_t) + sizeof(xfs_bmbt_ptr_t))))
 206
 207 /*
 208  * Maximum number of bmap btree levels.
 209  */
 210 #define XFS_BM_MAXLEVELS(mp,w)          ((mp)->m_bm_maxlevels[(w)])
 211
 212 /*
 213  * Prototypes for xfs_bmap.c to call.
 214  */
 215 extern void xfs_bmdr_to_bmbt(struct xfs_mount *, xfs_bmdr_block_t *, int,
 216                         struct xfs_btree_block *, int);
 217 extern void xfs_bmbt_get_all(xfs_bmbt_rec_host_t *r, xfs_bmbt_irec_t *s);
 218 extern xfs_filblks_t xfs_bmbt_get_blockcount(xfs_bmbt_rec_host_t *r);
 219 extern xfs_fsblock_t xfs_bmbt_get_startblock(xfs_bmbt_rec_host_t *r);
 220 extern xfs_fileoff_t xfs_bmbt_get_startoff(xfs_bmbt_rec_host_t *r);
 221 extern xfs_exntst_t xfs_bmbt_get_state(xfs_bmbt_rec_host_t *r);
 222
 223 extern void xfs_bmbt_disk_get_all(xfs_bmbt_rec_t *r, xfs_bmbt_irec_t *s);
 224 extern xfs_filblks_t xfs_bmbt_disk_get_blockcount(xfs_bmbt_rec_t *r);
 225 extern xfs_fileoff_t xfs_bmbt_disk_get_startoff(xfs_bmbt_rec_t *r);
 226
 227 extern void xfs_bmbt_set_all(xfs_bmbt_rec_host_t *r, xfs_bmbt_irec_t *s);
 228 extern void xfs_bmbt_set_allf(xfs_bmbt_rec_host_t *r, xfs_fileoff_t o,
 229                         xfs_fsblock_t b, xfs_filblks_t c, xfs_exntst_t v);
 230 extern void xfs_bmbt_set_blockcount(xfs_bmbt_rec_host_t *r, xfs_filblks_t v);
 231 extern void xfs_bmbt_set_startblock(xfs_bmbt_rec_host_t *r, xfs_fsblock_t v);
 232 extern void xfs_bmbt_set_startoff(xfs_bmbt_rec_host_t *r, xfs_fileoff_t v);
 233 extern void xfs_bmbt_set_state(xfs_bmbt_rec_host_t *r, xfs_exntst_t v);
 234
 235 extern void xfs_bmbt_disk_set_all(xfs_bmbt_rec_t *r, xfs_bmbt_irec_t *s);
 236 extern void xfs_bmbt_disk_set_allf(xfs_bmbt_rec_t *r, xfs_fileoff_t o,
 237                         xfs_fsblock_t b, xfs_filblks_t c, xfs_exntst_t v);
 238
 239 extern void xfs_bmbt_to_bmdr(struct xfs_mount *, struct xfs_btree_block *, int,
 240                         xfs_bmdr_block_t *, int);
 241
 242 extern int xfs_bmbt_get_maxrecs(struct xfs_btree_cur *, int level);
 243 extern int xfs_bmdr_maxrecs(struct xfs_mount *, int blocklen, int leaf);
 244 extern int xfs_bmbt_maxrecs(struct xfs_mount *, int blocklen, int leaf);
 245
 246 extern struct xfs_btree_cur *xfs_bmbt_init_cursor(struct xfs_mount *,
 247                 struct xfs_trans *, struct xfs_inode *, int);
 248
 249
 250 #endif  /* __XFS_BMAP_BTREE_H__ */