db/bmap.c

   1 /*
   2  * Copyright (c) 2000-2001,2005 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
  19 #include <xfs/libxfs.h>
  20 #include "command.h"
  21 #include "type.h"
  22 #include "fprint.h"
  23 #include "faddr.h"
  24 #include "field.h"
  25 #include "bmap.h"
  26 #include "io.h"
  27 #include "inode.h"
  28 #include "output.h"
  29 #include "init.h"
  30
  31 static int              bmap_f(int argc, char **argv);
  32 static int              bmap_one_extent(xfs_bmbt_rec_t *ep,
  33                                         xfs_fileoff_t *offp, xfs_fileoff_t eoff,
  34                                         int *idxp, bmap_ext_t *bep);
  35 static xfs_fsblock_t    select_child(xfs_fileoff_t off, xfs_bmbt_key_t *kp,
  36                                      xfs_bmbt_ptr_t *pp, int nrecs);
  37
  38 static const cmdinfo_t  bmap_cmd =
  39         { "bmap", NULL, bmap_f, 0, 3, 0, N_("[-ad] [block [len]]"),
  40           N_("show block map for current file"), NULL };
  41
  42 void
  43 bmap(
  44         xfs_fileoff_t           offset,
  45         xfs_filblks_t           len,
  46         int                     whichfork,
  47         int                     *nexp,
  48         bmap_ext_t              *bep)
  49 {
  50         struct xfs_btree_block  *block;
  51         xfs_fsblock_t           bno;
  52         xfs_fileoff_t           curoffset;
  53         xfs_dinode_t            *dip;
  54         xfs_fileoff_t           eoffset;
  55         xfs_bmbt_rec_t          *ep;
  56         xfs_dinode_fmt_t        fmt;
  57         int                     fsize;
  58         xfs_bmbt_key_t          *kp;
  59         int                     n;
  60         int                     nex;
  61         xfs_fsblock_t           nextbno;
  62         int                     nextents;
  63         xfs_bmbt_ptr_t          *pp;
  64         xfs_bmdr_block_t        *rblock;
  65         typnm_t                 typ;
  66         xfs_bmbt_rec_t          *xp;
  67
  68         push_cur();
  69         set_cur_inode(iocur_top->ino);
  70         nex = *nexp;
  71         *nexp = 0;
  72         ASSERT(nex > 0);
  73         dip = iocur_top->data;
  74         n = 0;
  75         eoffset = offset + len - 1;
  76         curoffset = offset;
  77         fmt = (xfs_dinode_fmt_t)XFS_DFORK_FORMAT(dip, whichfork);
  78         typ = whichfork == XFS_DATA_FORK ? TYP_BMAPBTD : TYP_BMAPBTA;
  79         ASSERT(typtab[typ].typnm == typ);
  80         ASSERT(fmt == XFS_DINODE_FMT_LOCAL || fmt == XFS_DINODE_FMT_EXTENTS ||
  81                 fmt == XFS_DINODE_FMT_BTREE);
  82         if (fmt == XFS_DINODE_FMT_EXTENTS) {
  83                 nextents = XFS_DFORK_NEXTENTS(dip, whichfork);
  84                 xp = (xfs_bmbt_rec_t *)XFS_DFORK_PTR(dip, whichfork);
  85                 for (ep = xp; ep < &xp[nextents] && n < nex; ep++) {
  86                         if (!bmap_one_extent(ep, &curoffset, eoffset, &n, bep))
  87                                 break;
  88                 }
  89         } else if (fmt == XFS_DINODE_FMT_BTREE) {
  90                 push_cur();
  91                 rblock = (xfs_bmdr_block_t *)XFS_DFORK_PTR(dip, whichfork);
  92                 fsize = XFS_DFORK_SIZE(dip, mp, whichfork);
  93                 pp = XFS_BMDR_PTR_ADDR(rblock, 1, xfs_bmdr_maxrecs(fsize, 0));
  94                 kp = XFS_BMDR_KEY_ADDR(rblock, 1);
  95                 bno = select_child(curoffset, kp, pp,
  96                                         be16_to_cpu(rblock->bb_numrecs));
  97                 for (;;) {
  98                         set_cur(&typtab[typ], XFS_FSB_TO_DADDR(mp, bno),
  99                                 blkbb, DB_RING_IGN, NULL);
 100                         block = (struct xfs_btree_block *)iocur_top->data;
 101                         if (be16_to_cpu(block->bb_level) == 0)
 102                                 break;
 103                         pp = XFS_BMBT_PTR_ADDR(mp, block, 1,
 104                                 xfs_bmbt_maxrecs(mp, mp->m_sb.sb_blocksize, 0));
 105                         kp = XFS_BMBT_KEY_ADDR(mp, block, 1);
 106                         bno = select_child(curoffset, kp, pp,
 107                                         be16_to_cpu(block->bb_numrecs));
 108                 }
 109                 for (;;) {
 110                         nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
 111                         nextents = be16_to_cpu(block->bb_numrecs);
 112                         xp = (xfs_bmbt_rec_t *)
 113                                 XFS_BMBT_REC_ADDR(mp, block, 1);
 114                         for (ep = xp; ep < &xp[nextents] && n < nex; ep++) {
 115                                 if (!bmap_one_extent(ep, &curoffset, eoffset,
 116                                                 &n, bep)) {
 117                                         nextbno = NULLFSBLOCK;
 118                                         break;
 119                                 }
 120                         }
 121                         bno = nextbno;
 122                         if (bno == NULLFSBLOCK)
 123                                 break;
 124                         set_cur(&typtab[typ], XFS_FSB_TO_DADDR(mp, bno),
 125                                 blkbb, DB_RING_IGN, NULL);
 126                         block = (struct xfs_btree_block *)iocur_top->data;
 127                 }
 128                 pop_cur();
 129         }
 130         pop_cur();
 131         *nexp = n;
 132 }
 133
 134 static int
 135 bmap_f(
 136         int             argc,
 137         char            **argv)
 138 {
 139         int             afork = 0;
 140         bmap_ext_t      be;
 141         int             c;
 142         xfs_fileoff_t   co, cosave;
 143         int             dfork = 0;
 144         xfs_dinode_t    *dip;
 145         xfs_fileoff_t   eo;
 146         xfs_filblks_t   len;
 147         int             nex;
 148         char            *p;
 149         int             whichfork;
 150
 151         if (iocur_top->ino == NULLFSINO) {
 152                 dbprintf(_("no current inode\n"));
 153                 return 0;
 154         }
 155         optind = 0;
 156         if (argc) while ((c = getopt(argc, argv, "ad")) != EOF) {
 157                 switch (c) {
 158                 case 'a':
 159                         afork = 1;
 160                         break;
 161                 case 'd':
 162                         dfork = 1;
 163                         break;
 164                 default:
 165                         dbprintf(_("bad option for bmap command\n"));
 166                         return 0;
 167                 }
 168         }
 169         if (afork + dfork == 0) {
 170                 push_cur();
 171                 set_cur_inode(iocur_top->ino);
 172                 dip = iocur_top->data;
 173                 if (be32_to_cpu(dip->di_nextents))
 174                         dfork = 1;
 175                 if (be16_to_cpu(dip->di_anextents))
 176                         afork = 1;
 177                 pop_cur();
 178         }
 179         if (optind < argc) {
 180                 co = (xfs_fileoff_t)strtoull(argv[optind], &p, 0);
 181                 if (*p != '\0') {
 182                         dbprintf(_("bad block number for bmap %s\n"),
 183                                 argv[optind]);
 184                         return 0;
 185                 }
 186                 optind++;
 187                 if (optind < argc) {
 188                         len = (xfs_filblks_t)strtoull(argv[optind], &p, 0);
 189                         if (*p != '\0') {
 190                                 dbprintf(_("bad len for bmap %s\n"), argv[optind]);
 191                                 return 0;
 192                         }
 193                         eo = co + len - 1;
 194                 } else
 195                         eo = co;
 196         } else {
 197                 co = 0;
 198                 eo = -1;
 199         }
 200         cosave = co;
 201         for (whichfork = XFS_DATA_FORK;
 202              whichfork <= XFS_ATTR_FORK;
 203              whichfork++) {
 204                 if (whichfork == XFS_DATA_FORK && !dfork)
 205                         continue;
 206                 if (whichfork == XFS_ATTR_FORK && !afork)
 207                         continue;
 208                 for (;;) {
 209                         nex = 1;
 210                         bmap(co, eo - co + 1, whichfork, &nex, &be);
 211                         if (nex == 0)
 212                                 break;
 213                         dbprintf(_("%s offset %lld startblock %llu (%u/%u) count "
 214                                  "%llu flag %u\n"),
 215                                 whichfork == XFS_DATA_FORK ? _("data") : _("attr"),
 216                                 be.startoff, be.startblock,
 217                                 XFS_FSB_TO_AGNO(mp, be.startblock),
 218                                 XFS_FSB_TO_AGBNO(mp, be.startblock),
 219                                 be.blockcount, be.flag);
 220                         co = be.startoff + be.blockcount;
 221                 }
 222                 co = cosave;
 223         }
 224         return 0;
 225 }
 226
 227 void
 228 bmap_init(void)
 229 {
 230         add_command(&bmap_cmd);
 231 }
 232
 233 static int
 234 bmap_one_extent(
 235         xfs_bmbt_rec_t          *ep,
 236         xfs_fileoff_t           *offp,
 237         xfs_fileoff_t           eoff,
 238         int                     *idxp,
 239         bmap_ext_t              *bep)
 240 {
 241         xfs_filblks_t           c;
 242         xfs_fileoff_t           curoffset;
 243         int                     f;
 244         int                     idx;
 245         xfs_fileoff_t           o;
 246         xfs_fsblock_t           s;
 247
 248         convert_extent(ep, &o, &s, &c, &f);
 249         curoffset = *offp;
 250         idx = *idxp;
 251         if (o + c <= curoffset)
 252                 return 1;
 253         if (o > eoff)
 254                 return 0;
 255         if (o < curoffset) {
 256                 c -= curoffset - o;
 257                 s += curoffset - o;
 258                 o = curoffset;
 259         }
 260         if (o + c - 1 > eoff)
 261                 c -= (o + c - 1) - eoff;
 262         bep[idx].startoff = o;
 263         bep[idx].startblock = s;
 264         bep[idx].blockcount = c;
 265         bep[idx].flag = f;
 266         *idxp = idx + 1;
 267         *offp = o + c;
 268         return 1;
 269 }
 270
 271 void
 272 convert_extent(
 273         xfs_bmbt_rec_t          *rp,
 274         xfs_fileoff_t           *op,
 275         xfs_fsblock_t           *sp,
 276         xfs_filblks_t           *cp,
 277         int                     *fp)
 278 {
 279         struct xfs_bmbt_irec    irec;
 280
 281         libxfs_bmbt_disk_get_all(rp, &irec);
 282         *fp = irec.br_state == XFS_EXT_UNWRITTEN;
 283         *op = irec.br_startoff;
 284         *sp = irec.br_startblock;
 285         *cp = irec.br_blockcount;
 286 }
 287
 288 void
 289 make_bbmap(
 290         bbmap_t         *bbmap,
 291         int             nex,
 292         bmap_ext_t      *bmp)
 293 {
 294         int             i;
 295
 296         for (i = 0; i < nex; i++) {
 297                 bbmap->b[i].bm_bn = XFS_FSB_TO_DADDR(mp, bmp[i].startblock);
 298                 bbmap->b[i].bm_len = XFS_FSB_TO_BB(mp, bmp[i].blockcount);
 299         }
 300         bbmap->nmaps = nex;
 301 }
 302
 303 static xfs_fsblock_t
 304 select_child(
 305         xfs_fileoff_t   off,
 306         xfs_bmbt_key_t  *kp,
 307         xfs_bmbt_ptr_t  *pp,
 308         int             nrecs)
 309 {
 310         int             i;
 311
 312         for (i = 0; i < nrecs; i++) {
 313                 if (be64_to_cpu(kp[i].br_startoff) == off)
 314                         return be64_to_cpu(pp[i]);
 315                 if (be64_to_cpu(kp[i].br_startoff) > off) {
 316                         if (i == 0)
 317                                 return be64_to_cpu(pp[i]);
 318                         else
 319                                 return be64_to_cpu(pp[i - 1]);
 320                 }
 321         }
 322         return be64_to_cpu(pp[nrecs - 1]);
 323 }