fs/xfs/xfs_fsops.c

   1 /*
   2  * Copyright (c) 2000-2005 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 #include "xfs.h"
  19 #include "xfs_fs.h"
  20 #include "xfs_types.h"
  21 #include "xfs_log.h"
  22 #include "xfs_trans.h"
  23 #include "xfs_sb.h"
  24 #include "xfs_ag.h"
  25 #include "xfs_mount.h"
  26 #include "xfs_bmap_btree.h"
  27 #include "xfs_alloc_btree.h"
  28 #include "xfs_ialloc_btree.h"
  29 #include "xfs_dinode.h"
  30 #include "xfs_inode.h"
  31 #include "xfs_inode_item.h"
  32 #include "xfs_btree.h"
  33 #include "xfs_error.h"
  34 #include "xfs_alloc.h"
  35 #include "xfs_ialloc.h"
  36 #include "xfs_fsops.h"
  37 #include "xfs_itable.h"
  38 #include "xfs_trans_space.h"
  39 #include "xfs_rtalloc.h"
  40 #include "xfs_filestream.h"
  41 #include "xfs_trace.h"
  42
  43 /*
  44  * File system operations
  45  */
  46
  47 int
  48 xfs_fs_geometry(
  49         xfs_mount_t             *mp,
  50         xfs_fsop_geom_t         *geo,
  51         int                     new_version)
  52 {
  53
  54         memset(geo, 0, sizeof(*geo));
  55
  56         geo->blocksize = mp->m_sb.sb_blocksize;
  57         geo->rtextsize = mp->m_sb.sb_rextsize;
  58         geo->agblocks = mp->m_sb.sb_agblocks;
  59         geo->agcount = mp->m_sb.sb_agcount;
  60         geo->logblocks = mp->m_sb.sb_logblocks;
  61         geo->sectsize = mp->m_sb.sb_sectsize;
  62         geo->inodesize = mp->m_sb.sb_inodesize;
  63         geo->imaxpct = mp->m_sb.sb_imax_pct;
  64         geo->datablocks = mp->m_sb.sb_dblocks;
  65         geo->rtblocks = mp->m_sb.sb_rblocks;
  66         geo->rtextents = mp->m_sb.sb_rextents;
  67         geo->logstart = mp->m_sb.sb_logstart;
  68         ASSERT(sizeof(geo->uuid)==sizeof(mp->m_sb.sb_uuid));
  69         memcpy(geo->uuid, &mp->m_sb.sb_uuid, sizeof(mp->m_sb.sb_uuid));
  70         if (new_version >= 2) {
  71                 geo->sunit = mp->m_sb.sb_unit;
  72                 geo->swidth = mp->m_sb.sb_width;
  73         }
  74         if (new_version >= 3) {
  75                 geo->version = XFS_FSOP_GEOM_VERSION;
  76                 geo->flags =
  77                         (xfs_sb_version_hasattr(&mp->m_sb) ?
  78                                 XFS_FSOP_GEOM_FLAGS_ATTR : 0) |
  79                         (xfs_sb_version_hasnlink(&mp->m_sb) ?
  80                                 XFS_FSOP_GEOM_FLAGS_NLINK : 0) |
  81                         (xfs_sb_version_hasquota(&mp->m_sb) ?
  82                                 XFS_FSOP_GEOM_FLAGS_QUOTA : 0) |
  83                         (xfs_sb_version_hasalign(&mp->m_sb) ?
  84                                 XFS_FSOP_GEOM_FLAGS_IALIGN : 0) |
  85                         (xfs_sb_version_hasdalign(&mp->m_sb) ?
  86                                 XFS_FSOP_GEOM_FLAGS_DALIGN : 0) |
  87                         (xfs_sb_version_hasshared(&mp->m_sb) ?
  88                                 XFS_FSOP_GEOM_FLAGS_SHARED : 0) |
  89                         (xfs_sb_version_hasextflgbit(&mp->m_sb) ?
  90                                 XFS_FSOP_GEOM_FLAGS_EXTFLG : 0) |
  91                         (xfs_sb_version_hasdirv2(&mp->m_sb) ?
  92                                 XFS_FSOP_GEOM_FLAGS_DIRV2 : 0) |
  93                         (xfs_sb_version_hassector(&mp->m_sb) ?
  94                                 XFS_FSOP_GEOM_FLAGS_SECTOR : 0) |
  95                         (xfs_sb_version_hasasciici(&mp->m_sb) ?
  96                                 XFS_FSOP_GEOM_FLAGS_DIRV2CI : 0) |
  97                         (xfs_sb_version_haslazysbcount(&mp->m_sb) ?
  98                                 XFS_FSOP_GEOM_FLAGS_LAZYSB : 0) |
  99                         (xfs_sb_version_hasattr2(&mp->m_sb) ?
 100                                 XFS_FSOP_GEOM_FLAGS_ATTR2 : 0);
 101                 geo->logsectsize = xfs_sb_version_hassector(&mp->m_sb) ?
 102                                 mp->m_sb.sb_logsectsize : BBSIZE;
 103                 geo->rtsectsize = mp->m_sb.sb_blocksize;
 104                 geo->dirblocksize = mp->m_dirblksize;
 105         }
 106         if (new_version >= 4) {
 107                 geo->flags |=
 108                         (xfs_sb_version_haslogv2(&mp->m_sb) ?
 109                                 XFS_FSOP_GEOM_FLAGS_LOGV2 : 0);
 110                 geo->logsunit = mp->m_sb.sb_logsunit;
 111         }
 112         return 0;
 113 }
 114
 115 static int
 116 xfs_growfs_data_private(
 117         xfs_mount_t             *mp,            /* mount point for filesystem */
 118         xfs_growfs_data_t       *in)            /* growfs data input struct */
 119 {
 120         xfs_agf_t               *agf;
 121         xfs_agi_t               *agi;
 122         xfs_agnumber_t          agno;
 123         xfs_extlen_t            agsize;
 124         xfs_extlen_t            tmpsize;
 125         xfs_alloc_rec_t         *arec;
 126         struct xfs_btree_block  *block;
 127         xfs_buf_t               *bp;
 128         int                     bucket;
 129         int                     dpct;
 130         int                     error;
 131         xfs_agnumber_t          nagcount;
 132         xfs_agnumber_t          nagimax = 0;
 133         xfs_rfsblock_t          nb, nb_mod;
 134         xfs_rfsblock_t          new;
 135         xfs_rfsblock_t          nfree;
 136         xfs_agnumber_t          oagcount;
 137         int                     pct;
 138         xfs_trans_t             *tp;
 139
 140         nb = in->newblocks;
 141         pct = in->imaxpct;
 142         if (nb < mp->m_sb.sb_dblocks || pct < 0 || pct > 100)
 143                 return XFS_ERROR(EINVAL);
 144         if ((error = xfs_sb_validate_fsb_count(&mp->m_sb, nb)))
 145                 return error;
 146         dpct = pct - mp->m_sb.sb_imax_pct;
 147         bp = xfs_buf_read_uncached(mp->m_ddev_targp,
 148                                 XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),
 149                                 XFS_FSS_TO_BB(mp, 1), 0);
 150         if (!bp)
 151                 return EIO;
 152         xfs_buf_relse(bp);
 153
 154         new = nb;       /* use new as a temporary here */
 155         nb_mod = do_div(new, mp->m_sb.sb_agblocks);
 156         nagcount = new + (nb_mod != 0);
 157         if (nb_mod && nb_mod < XFS_MIN_AG_BLOCKS) {
 158                 nagcount--;
 159                 nb = (xfs_rfsblock_t)nagcount * mp->m_sb.sb_agblocks;
 160                 if (nb < mp->m_sb.sb_dblocks)
 161                         return XFS_ERROR(EINVAL);
 162         }
 163         new = nb - mp->m_sb.sb_dblocks;
 164         oagcount = mp->m_sb.sb_agcount;
 165
 166         /* allocate the new per-ag structures */
 167         if (nagcount > oagcount) {
 168                 error = xfs_initialize_perag(mp, nagcount, &nagimax);
 169                 if (error)
 170                         return error;
 171         }
 172
 173         tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFS);
 174         tp->t_flags |= XFS_TRANS_RESERVE;
 175         if ((error = xfs_trans_reserve(tp, XFS_GROWFS_SPACE_RES(mp),
 176                         XFS_GROWDATA_LOG_RES(mp), 0, 0, 0))) {
 177                 xfs_trans_cancel(tp, 0);
 178                 return error;
 179         }
 180
 181         /*
 182          * Write new AG headers to disk. Non-transactional, but written
 183          * synchronously so they are completed prior to the growfs transaction
 184          * being logged.
 185          */
 186         nfree = 0;
 187         for (agno = nagcount - 1; agno >= oagcount; agno--, new -= agsize) {
 188                 /*
 189                  * AG freelist header block
 190                  */
 191                 bp = xfs_buf_get(mp->m_ddev_targp,
 192                                  XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
 193                                  XFS_FSS_TO_BB(mp, 1), 0);
 194                 if (!bp) {
 195                         error = ENOMEM;
 196                         goto error0;
 197                 }
 198                 agf = XFS_BUF_TO_AGF(bp);
 199                 memset(agf, 0, mp->m_sb.sb_sectsize);
 200                 agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
 201                 agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
 202                 agf->agf_seqno = cpu_to_be32(agno);
 203                 if (agno == nagcount - 1)
 204                         agsize =
 205                                 nb -
 206                                 (agno * (xfs_rfsblock_t)mp->m_sb.sb_agblocks);
 207                 else
 208                         agsize = mp->m_sb.sb_agblocks;
 209                 agf->agf_length = cpu_to_be32(agsize);
 210                 agf->agf_roots[XFS_BTNUM_BNOi] = cpu_to_be32(XFS_BNO_BLOCK(mp));
 211                 agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(XFS_CNT_BLOCK(mp));
 212                 agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(1);
 213                 agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(1);
 214                 agf->agf_flfirst = 0;
 215                 agf->agf_fllast = cpu_to_be32(XFS_AGFL_SIZE(mp) - 1);
 216                 agf->agf_flcount = 0;
 217                 tmpsize = agsize - XFS_PREALLOC_BLOCKS(mp);
 218                 agf->agf_freeblks = cpu_to_be32(tmpsize);
 219                 agf->agf_longest = cpu_to_be32(tmpsize);
 220                 error = xfs_bwrite(bp);
 221                 xfs_buf_relse(bp);
 222                 if (error)
 223                         goto error0;
 224
 225                 /*
 226                  * AG inode header block
 227                  */
 228                 bp = xfs_buf_get(mp->m_ddev_targp,
 229                                  XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
 230                                  XFS_FSS_TO_BB(mp, 1), 0);
 231                 if (!bp) {
 232                         error = ENOMEM;
 233                         goto error0;
 234                 }
 235                 agi = XFS_BUF_TO_AGI(bp);
 236                 memset(agi, 0, mp->m_sb.sb_sectsize);
 237                 agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
 238                 agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
 239                 agi->agi_seqno = cpu_to_be32(agno);
 240                 agi->agi_length = cpu_to_be32(agsize);
 241                 agi->agi_count = 0;
 242                 agi->agi_root = cpu_to_be32(XFS_IBT_BLOCK(mp));
 243                 agi->agi_level = cpu_to_be32(1);
 244                 agi->agi_freecount = 0;
 245                 agi->agi_newino = cpu_to_be32(NULLAGINO);
 246                 agi->agi_dirino = cpu_to_be32(NULLAGINO);
 247                 for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
 248                         agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
 249                 error = xfs_bwrite(bp);
 250                 xfs_buf_relse(bp);
 251                 if (error)
 252                         goto error0;
 253
 254                 /*
 255                  * BNO btree root block
 256                  */
 257                 bp = xfs_buf_get(mp->m_ddev_targp,
 258                                  XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
 259                                  BTOBB(mp->m_sb.sb_blocksize), 0);
 260                 if (!bp) {
 261                         error = ENOMEM;
 262                         goto error0;
 263                 }
 264                 block = XFS_BUF_TO_BLOCK(bp);
 265                 memset(block, 0, mp->m_sb.sb_blocksize);
 266                 block->bb_magic = cpu_to_be32(XFS_ABTB_MAGIC);
 267                 block->bb_level = 0;
 268                 block->bb_numrecs = cpu_to_be16(1);
 269                 block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
 270                 block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
 271                 arec = XFS_ALLOC_REC_ADDR(mp, block, 1);
 272                 arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
 273                 arec->ar_blockcount = cpu_to_be32(
 274                         agsize - be32_to_cpu(arec->ar_startblock));
 275                 error = xfs_bwrite(bp);
 276                 xfs_buf_relse(bp);
 277                 if (error)
 278                         goto error0;
 279
 280                 /*
 281                  * CNT btree root block
 282                  */
 283                 bp = xfs_buf_get(mp->m_ddev_targp,
 284                                  XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
 285                                  BTOBB(mp->m_sb.sb_blocksize), 0);
 286                 if (!bp) {
 287                         error = ENOMEM;
 288                         goto error0;
 289                 }
 290                 block = XFS_BUF_TO_BLOCK(bp);
 291                 memset(block, 0, mp->m_sb.sb_blocksize);
 292                 block->bb_magic = cpu_to_be32(XFS_ABTC_MAGIC);
 293                 block->bb_level = 0;
 294                 block->bb_numrecs = cpu_to_be16(1);
 295                 block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
 296                 block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
 297                 arec = XFS_ALLOC_REC_ADDR(mp, block, 1);
 298                 arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
 299                 arec->ar_blockcount = cpu_to_be32(
 300                         agsize - be32_to_cpu(arec->ar_startblock));
 301                 nfree += be32_to_cpu(arec->ar_blockcount);
 302                 error = xfs_bwrite(bp);
 303                 xfs_buf_relse(bp);
 304                 if (error)
 305                         goto error0;
 306
 307                 /*
 308                  * INO btree root block
 309                  */
 310                 bp = xfs_buf_get(mp->m_ddev_targp,
 311                                  XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
 312                                  BTOBB(mp->m_sb.sb_blocksize), 0);
 313                 if (!bp) {
 314                         error = ENOMEM;
 315                         goto error0;
 316                 }
 317                 block = XFS_BUF_TO_BLOCK(bp);
 318                 memset(block, 0, mp->m_sb.sb_blocksize);
 319                 block->bb_magic = cpu_to_be32(XFS_IBT_MAGIC);
 320                 block->bb_level = 0;
 321                 block->bb_numrecs = 0;
 322                 block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
 323                 block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
 324                 error = xfs_bwrite(bp);
 325                 xfs_buf_relse(bp);
 326                 if (error)
 327                         goto error0;
 328         }
 329         xfs_trans_agblocks_delta(tp, nfree);
 330         /*
 331          * There are new blocks in the old last a.g.
 332          */
 333         if (new) {
 334                 /*
 335                  * Change the agi length.
 336                  */
 337                 error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
 338                 if (error) {
 339                         goto error0;
 340                 }
 341                 ASSERT(bp);
 342                 agi = XFS_BUF_TO_AGI(bp);
 343                 be32_add_cpu(&agi->agi_length, new);
 344                 ASSERT(nagcount == oagcount ||
 345                        be32_to_cpu(agi->agi_length) == mp->m_sb.sb_agblocks);
 346                 xfs_ialloc_log_agi(tp, bp, XFS_AGI_LENGTH);
 347                 /*
 348                  * Change agf length.
 349                  */
 350                 error = xfs_alloc_read_agf(mp, tp, agno, 0, &bp);
 351                 if (error) {
 352                         goto error0;
 353                 }
 354                 ASSERT(bp);
 355                 agf = XFS_BUF_TO_AGF(bp);
 356                 be32_add_cpu(&agf->agf_length, new);
 357                 ASSERT(be32_to_cpu(agf->agf_length) ==
 358                        be32_to_cpu(agi->agi_length));
 359
 360                 xfs_alloc_log_agf(tp, bp, XFS_AGF_LENGTH);
 361                 /*
 362                  * Free the new space.
 363                  */
 364                 error = xfs_free_extent(tp, XFS_AGB_TO_FSB(mp, agno,
 365                         be32_to_cpu(agf->agf_length) - new), new);
 366                 if (error) {
 367                         goto error0;
 368                 }
 369         }
 370
 371         /*
 372          * Update changed superblock fields transactionally. These are not
 373          * seen by the rest of the world until the transaction commit applies
 374          * them atomically to the superblock.
 375          */
 376         if (nagcount > oagcount)
 377                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);
 378         if (nb > mp->m_sb.sb_dblocks)
 379                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS,
 380                                  nb - mp->m_sb.sb_dblocks);
 381         if (nfree)
 382                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, nfree);
 383         if (dpct)
 384                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);
 385         error = xfs_trans_commit(tp, 0);
 386         if (error)
 387                 return error;
 388
 389         /* New allocation groups fully initialized, so update mount struct */
 390         if (nagimax)
 391                 mp->m_maxagi = nagimax;
 392         if (mp->m_sb.sb_imax_pct) {
 393                 __uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct;
 394                 do_div(icount, 100);
 395                 mp->m_maxicount = icount << mp->m_sb.sb_inopblog;
 396         } else
 397                 mp->m_maxicount = 0;
 398         xfs_set_low_space_thresholds(mp);
 399
 400         /* update secondary superblocks. */
 401         for (agno = 1; agno < nagcount; agno++) {
 402                 error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp,
 403                                   XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
 404                                   XFS_FSS_TO_BB(mp, 1), 0, &bp);
 405                 if (error) {
 406                         xfs_warn(mp,
 407                 "error %d reading secondary superblock for ag %d",
 408                                 error, agno);
 409                         break;
 410                 }
 411                 xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb, XFS_SB_ALL_BITS);
 412                 /*
 413                  * If we get an error writing out the alternate superblocks,
 414                  * just issue a warning and continue.  The real work is
 415                  * already done and committed.
 416                  */
 417                 error = xfs_bwrite(bp);
 418                 xfs_buf_relse(bp);
 419                 if (error) {
 420                         xfs_warn(mp,
 421                 "write error %d updating secondary superblock for ag %d",
 422                                 error, agno);
 423                         break; /* no point in continuing */
 424                 }
 425         }
 426         return 0;
 427
 428  error0:
 429         xfs_trans_cancel(tp, XFS_TRANS_ABORT);
 430         return error;
 431 }
 432
 433 static int
 434 xfs_growfs_log_private(
 435         xfs_mount_t             *mp,    /* mount point for filesystem */
 436         xfs_growfs_log_t        *in)    /* growfs log input struct */
 437 {
 438         xfs_extlen_t            nb;
 439
 440         nb = in->newblocks;
 441         if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES))
 442                 return XFS_ERROR(EINVAL);
 443         if (nb == mp->m_sb.sb_logblocks &&
 444             in->isint == (mp->m_sb.sb_logstart != 0))
 445                 return XFS_ERROR(EINVAL);
 446         /*
 447          * Moving the log is hard, need new interfaces to sync
 448          * the log first, hold off all activity while moving it.
 449          * Can have shorter or longer log in the same space,
 450          * or transform internal to external log or vice versa.
 451          */
 452         return XFS_ERROR(ENOSYS);
 453 }
 454
 455 /*
 456  * protected versions of growfs function acquire and release locks on the mount
 457  * point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG,
 458  * XFS_IOC_FSGROWFSRT
 459  */
 460
 461
 462 int
 463 xfs_growfs_data(
 464         xfs_mount_t             *mp,
 465         xfs_growfs_data_t       *in)
 466 {
 467         int error;
 468
 469         if (!capable(CAP_SYS_ADMIN))
 470                 return XFS_ERROR(EPERM);
 471         if (!mutex_trylock(&mp->m_growlock))
 472                 return XFS_ERROR(EWOULDBLOCK);
 473         error = xfs_growfs_data_private(mp, in);
 474         mutex_unlock(&mp->m_growlock);
 475         return error;
 476 }
 477
 478 int
 479 xfs_growfs_log(
 480         xfs_mount_t             *mp,
 481         xfs_growfs_log_t        *in)
 482 {
 483         int error;
 484
 485         if (!capable(CAP_SYS_ADMIN))
 486                 return XFS_ERROR(EPERM);
 487         if (!mutex_trylock(&mp->m_growlock))
 488                 return XFS_ERROR(EWOULDBLOCK);
 489         error = xfs_growfs_log_private(mp, in);
 490         mutex_unlock(&mp->m_growlock);
 491         return error;
 492 }
 493
 494 /*
 495  * exported through ioctl XFS_IOC_FSCOUNTS
 496  */
 497
 498 int
 499 xfs_fs_counts(
 500         xfs_mount_t             *mp,
 501         xfs_fsop_counts_t       *cnt)
 502 {
 503         xfs_icsb_sync_counters(mp, XFS_ICSB_LAZY_COUNT);
 504         spin_lock(&mp->m_sb_lock);
 505         cnt->freedata = mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
 506         cnt->freertx = mp->m_sb.sb_frextents;
 507         cnt->freeino = mp->m_sb.sb_ifree;
 508         cnt->allocino = mp->m_sb.sb_icount;
 509         spin_unlock(&mp->m_sb_lock);
 510         return 0;
 511 }
 512
 513 /*
 514  * exported through ioctl XFS_IOC_SET_RESBLKS & XFS_IOC_GET_RESBLKS
 515  *
 516  * xfs_reserve_blocks is called to set m_resblks
 517  * in the in-core mount table. The number of unused reserved blocks
 518  * is kept in m_resblks_avail.
 519  *
 520  * Reserve the requested number of blocks if available. Otherwise return
 521  * as many as possible to satisfy the request. The actual number
 522  * reserved are returned in outval
 523  *
 524  * A null inval pointer indicates that only the current reserved blocks
 525  * available  should  be returned no settings are changed.
 526  */
 527
 528 int
 529 xfs_reserve_blocks(
 530         xfs_mount_t             *mp,
 531         __uint64_t              *inval,
 532         xfs_fsop_resblks_t      *outval)
 533 {
 534         __int64_t               lcounter, delta, fdblks_delta;
 535         __uint64_t              request;
 536
 537         /* If inval is null, report current values and return */
 538         if (inval == (__uint64_t *)NULL) {
 539                 if (!outval)
 540                         return EINVAL;
 541                 outval->resblks = mp->m_resblks;
 542                 outval->resblks_avail = mp->m_resblks_avail;
 543                 return 0;
 544         }
 545
 546         request = *inval;
 547
 548         /*
 549          * With per-cpu counters, this becomes an interesting
 550          * problem. we needto work out if we are freeing or allocation
 551          * blocks first, then we can do the modification as necessary.
 552          *
 553          * We do this under the m_sb_lock so that if we are near
 554          * ENOSPC, we will hold out any changes while we work out
 555          * what to do. This means that the amount of free space can
 556          * change while we do this, so we need to retry if we end up
 557          * trying to reserve more space than is available.
 558          *
 559          * We also use the xfs_mod_incore_sb() interface so that we
 560          * don't have to care about whether per cpu counter are
 561          * enabled, disabled or even compiled in....
 562          */
 563 retry:
 564         spin_lock(&mp->m_sb_lock);
 565         xfs_icsb_sync_counters_locked(mp, 0);
 566
 567         /*
 568          * If our previous reservation was larger than the current value,
 569          * then move any unused blocks back to the free pool.
 570          */
 571         fdblks_delta = 0;
 572         if (mp->m_resblks > request) {
 573                 lcounter = mp->m_resblks_avail - request;
 574                 if (lcounter  > 0) {            /* release unused blocks */
 575                         fdblks_delta = lcounter;
 576                         mp->m_resblks_avail -= lcounter;
 577                 }
 578                 mp->m_resblks = request;
 579         } else {
 580                 __int64_t       free;
 581
 582                 free =  mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
 583                 if (!free)
 584                         goto out; /* ENOSPC and fdblks_delta = 0 */
 585
 586                 delta = request - mp->m_resblks;
 587                 lcounter = free - delta;
 588                 if (lcounter < 0) {
 589                         /* We can't satisfy the request, just get what we can */
 590                         mp->m_resblks += free;
 591                         mp->m_resblks_avail += free;
 592                         fdblks_delta = -free;
 593                 } else {
 594                         fdblks_delta = -delta;
 595                         mp->m_resblks = request;
 596                         mp->m_resblks_avail += delta;
 597                 }
 598         }
 599 out:
 600         if (outval) {
 601                 outval->resblks = mp->m_resblks;
 602                 outval->resblks_avail = mp->m_resblks_avail;
 603         }
 604         spin_unlock(&mp->m_sb_lock);
 605
 606         if (fdblks_delta) {
 607                 /*
 608                  * If we are putting blocks back here, m_resblks_avail is
 609                  * already at its max so this will put it in the free pool.
 610                  *
 611                  * If we need space, we'll either succeed in getting it
 612                  * from the free block count or we'll get an enospc. If
 613                  * we get a ENOSPC, it means things changed while we were
 614                  * calculating fdblks_delta and so we should try again to
 615                  * see if there is anything left to reserve.
 616                  *
 617                  * Don't set the reserved flag here - we don't want to reserve
 618                  * the extra reserve blocks from the reserve.....
 619                  */
 620                 int error;
 621                 error = xfs_icsb_modify_counters(mp, XFS_SBS_FDBLOCKS,
 622                                                  fdblks_delta, 0);
 623                 if (error == ENOSPC)
 624                         goto retry;
 625         }
 626         return 0;
 627 }
 628
 629 /*
 630  * Dump a transaction into the log that contains no real change. This is needed
 631  * to be able to make the log dirty or stamp the current tail LSN into the log
 632  * during the covering operation.
 633  *
 634  * We cannot use an inode here for this - that will push dirty state back up
 635  * into the VFS and then periodic inode flushing will prevent log covering from
 636  * making progress. Hence we log a field in the superblock instead and use a
 637  * synchronous transaction to ensure the superblock is immediately unpinned
 638  * and can be written back.
 639  */
 640 int
 641 xfs_fs_log_dummy(
 642         xfs_mount_t     *mp)
 643 {
 644         xfs_trans_t     *tp;
 645         int             error;
 646
 647         tp = _xfs_trans_alloc(mp, XFS_TRANS_DUMMY1, KM_SLEEP);
 648         error = xfs_trans_reserve(tp, 0, mp->m_sb.sb_sectsize + 128, 0, 0,
 649                                         XFS_DEFAULT_LOG_COUNT);
 650         if (error) {
 651                 xfs_trans_cancel(tp, 0);
 652                 return error;
 653         }
 654
 655         /* log the UUID because it is an unchanging field */
 656         xfs_mod_sb(tp, XFS_SB_UUID);
 657         xfs_trans_set_sync(tp);
 658         return xfs_trans_commit(tp, 0);
 659 }
 660
 661 int
 662 xfs_fs_goingdown(
 663         xfs_mount_t     *mp,
 664         __uint32_t      inflags)
 665 {
 666         switch (inflags) {
 667         case XFS_FSOP_GOING_FLAGS_DEFAULT: {
 668                 struct super_block *sb = freeze_bdev(mp->m_super->s_bdev);
 669
 670                 if (sb && !IS_ERR(sb)) {
 671                         xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
 672                         thaw_bdev(sb->s_bdev, sb);
 673                 }
 674
 675                 break;
 676         }
 677         case XFS_FSOP_GOING_FLAGS_LOGFLUSH:
 678                 xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
 679                 break;
 680         case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH:
 681                 xfs_force_shutdown(mp,
 682                                 SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR);
 683                 break;
 684         default:
 685                 return XFS_ERROR(EINVAL);
 686         }
 687
 688         return 0;
 689 }
 690
 691 /*
 692  * Force a shutdown of the filesystem instantly while keeping the filesystem
 693  * consistent. We don't do an unmount here; just shutdown the shop, make sure
 694  * that absolutely nothing persistent happens to this filesystem after this
 695  * point.
 696  */
 697 void
 698 xfs_do_force_shutdown(
 699         xfs_mount_t     *mp,
 700         int             flags,
 701         char            *fname,
 702         int             lnnum)
 703 {
 704         int             logerror;
 705
 706         logerror = flags & SHUTDOWN_LOG_IO_ERROR;
 707
 708         if (!(flags & SHUTDOWN_FORCE_UMOUNT)) {
 709                 xfs_notice(mp,
 710         "%s(0x%x) called from line %d of file %s.  Return address = 0x%p",
 711                         __func__, flags, lnnum, fname, __return_address);
 712         }
 713         /*
 714          * No need to duplicate efforts.
 715          */
 716         if (XFS_FORCED_SHUTDOWN(mp) && !logerror)
 717                 return;
 718
 719         /*
 720          * This flags XFS_MOUNT_FS_SHUTDOWN, makes sure that we don't
 721          * queue up anybody new on the log reservations, and wakes up
 722          * everybody who's sleeping on log reservations to tell them
 723          * the bad news.
 724          */
 725         if (xfs_log_force_umount(mp, logerror))
 726                 return;
 727
 728         if (flags & SHUTDOWN_CORRUPT_INCORE) {
 729                 xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_CORRUPT,
 730     "Corruption of in-memory data detected.  Shutting down filesystem");
 731                 if (XFS_ERRLEVEL_HIGH <= xfs_error_level)
 732                         xfs_stack_trace();
 733         } else if (!(flags & SHUTDOWN_FORCE_UMOUNT)) {
 734                 if (logerror) {
 735                         xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_LOGERROR,
 736                 "Log I/O Error Detected.  Shutting down filesystem");
 737                 } else if (flags & SHUTDOWN_DEVICE_REQ) {
 738                         xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_IOERROR,
 739                 "All device paths lost.  Shutting down filesystem");
 740                 } else if (!(flags & SHUTDOWN_REMOTE_REQ)) {
 741                         xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_IOERROR,
 742                 "I/O Error Detected. Shutting down filesystem");
 743                 }
 744         }
 745         if (!(flags & SHUTDOWN_FORCE_UMOUNT)) {
 746                 xfs_alert(mp,
 747         "Please umount the filesystem and rectify the problem(s)");
 748         }
 749 }