SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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_bit.h"
  22 #include "xfs_inum.h"
  23 #include "xfs_log.h"
  24 #include "xfs_trans.h"
  25 #include "xfs_sb.h"
  26 #include "xfs_ag.h"
  27 #include "xfs_dir2.h"
  28 #include "xfs_dmapi.h"
  29 #include "xfs_mount.h"
  30 #include "xfs_bmap_btree.h"
  31 #include "xfs_alloc_btree.h"
  32 #include "xfs_ialloc_btree.h"
  33 #include "xfs_dir2_sf.h"
  34 #include "xfs_attr_sf.h"
  35 #include "xfs_dinode.h"
  36 #include "xfs_inode.h"
  37 #include "xfs_inode_item.h"
  38 #include "xfs_btree.h"
  39 #include "xfs_error.h"
  40 #include "xfs_alloc.h"
  41 #include "xfs_ialloc.h"
  42 #include "xfs_fsops.h"
  43 #include "xfs_itable.h"
  44 #include "xfs_trans_space.h"
  45 #include "xfs_rtalloc.h"
  46 #include "xfs_rw.h"
  47 #include "xfs_filestream.h"
  48
  49 /*
  50  * File system operations
  51  */
  52
  53 int
  54 xfs_fs_geometry(
  55         xfs_mount_t             *mp,
  56         xfs_fsop_geom_t         *geo,
  57         int                     new_version)
  58 {
  59         geo->blocksize = mp->m_sb.sb_blocksize;
  60         geo->rtextsize = mp->m_sb.sb_rextsize;
  61         geo->agblocks = mp->m_sb.sb_agblocks;
  62         geo->agcount = mp->m_sb.sb_agcount;
  63         geo->logblocks = mp->m_sb.sb_logblocks;
  64         geo->sectsize = mp->m_sb.sb_sectsize;
  65         geo->inodesize = mp->m_sb.sb_inodesize;
  66         geo->imaxpct = mp->m_sb.sb_imax_pct;
  67         geo->datablocks = mp->m_sb.sb_dblocks;
  68         geo->rtblocks = mp->m_sb.sb_rblocks;
  69         geo->rtextents = mp->m_sb.sb_rextents;
  70         geo->logstart = mp->m_sb.sb_logstart;
  71         ASSERT(sizeof(geo->uuid)==sizeof(mp->m_sb.sb_uuid));
  72         memcpy(geo->uuid, &mp->m_sb.sb_uuid, sizeof(mp->m_sb.sb_uuid));
  73         if (new_version >= 2) {
  74                 geo->sunit = mp->m_sb.sb_unit;
  75                 geo->swidth = mp->m_sb.sb_width;
  76         }
  77         if (new_version >= 3) {
  78                 geo->version = XFS_FSOP_GEOM_VERSION;
  79                 geo->flags =
  80                         (xfs_sb_version_hasattr(&mp->m_sb) ?
  81                                 XFS_FSOP_GEOM_FLAGS_ATTR : 0) |
  82                         (xfs_sb_version_hasnlink(&mp->m_sb) ?
  83                                 XFS_FSOP_GEOM_FLAGS_NLINK : 0) |
  84                         (xfs_sb_version_hasquota(&mp->m_sb) ?
  85                                 XFS_FSOP_GEOM_FLAGS_QUOTA : 0) |
  86                         (xfs_sb_version_hasalign(&mp->m_sb) ?
  87                                 XFS_FSOP_GEOM_FLAGS_IALIGN : 0) |
  88                         (xfs_sb_version_hasdalign(&mp->m_sb) ?
  89                                 XFS_FSOP_GEOM_FLAGS_DALIGN : 0) |
  90                         (xfs_sb_version_hasshared(&mp->m_sb) ?
  91                                 XFS_FSOP_GEOM_FLAGS_SHARED : 0) |
  92                         (xfs_sb_version_hasextflgbit(&mp->m_sb) ?
  93                                 XFS_FSOP_GEOM_FLAGS_EXTFLG : 0) |
  94                         (xfs_sb_version_hasdirv2(&mp->m_sb) ?
  95                                 XFS_FSOP_GEOM_FLAGS_DIRV2 : 0) |
  96                         (xfs_sb_version_hassector(&mp->m_sb) ?
  97                                 XFS_FSOP_GEOM_FLAGS_SECTOR : 0) |
  98                         (xfs_sb_version_hasasciici(&mp->m_sb) ?
  99                                 XFS_FSOP_GEOM_FLAGS_DIRV2CI : 0) |
 100                         (xfs_sb_version_haslazysbcount(&mp->m_sb) ?
 101                                 XFS_FSOP_GEOM_FLAGS_LAZYSB : 0) |
 102                         (xfs_sb_version_hasattr2(&mp->m_sb) ?
 103                                 XFS_FSOP_GEOM_FLAGS_ATTR2 : 0);
 104                 geo->logsectsize = xfs_sb_version_hassector(&mp->m_sb) ?
 105                                 mp->m_sb.sb_logsectsize : BBSIZE;
 106                 geo->rtsectsize = mp->m_sb.sb_blocksize;
 107                 geo->dirblocksize = mp->m_dirblksize;
 108         }
 109         if (new_version >= 4) {
 110                 geo->flags |=
 111                         (xfs_sb_version_haslogv2(&mp->m_sb) ?
 112                                 XFS_FSOP_GEOM_FLAGS_LOGV2 : 0);
 113                 geo->logsunit = mp->m_sb.sb_logsunit;
 114         }
 115         return 0;
 116 }
 117
 118 static int
 119 xfs_growfs_data_private(
 120         xfs_mount_t             *mp,            /* mount point for filesystem */
 121         xfs_growfs_data_t       *in)            /* growfs data input struct */
 122 {
 123         xfs_agf_t               *agf;
 124         xfs_agi_t               *agi;
 125         xfs_agnumber_t          agno;
 126         xfs_extlen_t            agsize;
 127         xfs_extlen_t            tmpsize;
 128         xfs_alloc_rec_t         *arec;
 129         struct xfs_btree_block  *block;
 130         xfs_buf_t               *bp;
 131         int                     bucket;
 132         int                     dpct;
 133         int                     error;
 134         xfs_agnumber_t          nagcount;
 135         xfs_agnumber_t          nagimax = 0;
 136         xfs_rfsblock_t          nb, nb_mod;
 137         xfs_rfsblock_t          new;
 138         xfs_rfsblock_t          nfree;
 139         xfs_agnumber_t          oagcount;
 140         int                     pct;
 141         xfs_trans_t             *tp;
 142
 143         nb = in->newblocks;
 144         pct = in->imaxpct;
 145         if (nb < mp->m_sb.sb_dblocks || pct < 0 || pct > 100)
 146                 return XFS_ERROR(EINVAL);
 147         if ((error = xfs_sb_validate_fsb_count(&mp->m_sb, nb)))
 148                 return error;
 149         dpct = pct - mp->m_sb.sb_imax_pct;
 150         error = xfs_read_buf(mp, mp->m_ddev_targp,
 151                         XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),
 152                         XFS_FSS_TO_BB(mp, 1), 0, &bp);
 153         if (error)
 154                 return error;
 155         ASSERT(bp);
 156         xfs_buf_relse(bp);
 157
 158         new = nb;       /* use new as a temporary here */
 159         nb_mod = do_div(new, mp->m_sb.sb_agblocks);
 160         nagcount = new + (nb_mod != 0);
 161         if (nb_mod && nb_mod < XFS_MIN_AG_BLOCKS) {
 162                 nagcount--;
 163                 nb = (xfs_rfsblock_t)nagcount * mp->m_sb.sb_agblocks;
 164                 if (nb < mp->m_sb.sb_dblocks)
 165                         return XFS_ERROR(EINVAL);
 166         }
 167         new = nb - mp->m_sb.sb_dblocks;
 168         oagcount = mp->m_sb.sb_agcount;
 169         if (nagcount > oagcount) {
 170                 void *new_perag, *old_perag;
 171
 172                 xfs_filestream_flush(mp);
 173
 174                 new_perag = kmem_zalloc(sizeof(xfs_perag_t) * nagcount,
 175                                         KM_MAYFAIL);
 176                 if (!new_perag)
 177                         return XFS_ERROR(ENOMEM);
 178
 179                 down_write(&mp->m_peraglock);
 180                 memcpy(new_perag, mp->m_perag, sizeof(xfs_perag_t) * oagcount);
 181                 old_perag = mp->m_perag;
 182                 mp->m_perag = new_perag;
 183
 184                 mp->m_flags |= XFS_MOUNT_32BITINODES;
 185                 nagimax = xfs_initialize_perag(mp, nagcount);
 186                 up_write(&mp->m_peraglock);
 187
 188                 kmem_free(old_perag);
 189         }
 190         tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFS);
 191         tp->t_flags |= XFS_TRANS_RESERVE;
 192         if ((error = xfs_trans_reserve(tp, XFS_GROWFS_SPACE_RES(mp),
 193                         XFS_GROWDATA_LOG_RES(mp), 0, 0, 0))) {
 194                 xfs_trans_cancel(tp, 0);
 195                 return error;
 196         }
 197
 198         nfree = 0;
 199         for (agno = nagcount - 1; agno >= oagcount; agno--, new -= agsize) {
 200                 /*
 201                  * AG freelist header block
 202                  */
 203                 bp = xfs_buf_get(mp->m_ddev_targp,
 204                                  XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
 205                                  XFS_FSS_TO_BB(mp, 1), XBF_LOCK | XBF_MAPPED);
 206                 agf = XFS_BUF_TO_AGF(bp);
 207                 memset(agf, 0, mp->m_sb.sb_sectsize);
 208                 agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
 209                 agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
 210                 agf->agf_seqno = cpu_to_be32(agno);
 211                 if (agno == nagcount - 1)
 212                         agsize =
 213                                 nb -
 214                                 (agno * (xfs_rfsblock_t)mp->m_sb.sb_agblocks);
 215                 else
 216                         agsize = mp->m_sb.sb_agblocks;
 217                 agf->agf_length = cpu_to_be32(agsize);
 218                 agf->agf_roots[XFS_BTNUM_BNOi] = cpu_to_be32(XFS_BNO_BLOCK(mp));
 219                 agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(XFS_CNT_BLOCK(mp));
 220                 agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(1);
 221                 agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(1);
 222                 agf->agf_flfirst = 0;
 223                 agf->agf_fllast = cpu_to_be32(XFS_AGFL_SIZE(mp) - 1);
 224                 agf->agf_flcount = 0;
 225                 tmpsize = agsize - XFS_PREALLOC_BLOCKS(mp);
 226                 agf->agf_freeblks = cpu_to_be32(tmpsize);
 227                 agf->agf_longest = cpu_to_be32(tmpsize);
 228                 error = xfs_bwrite(mp, bp);
 229                 if (error) {
 230                         goto error0;
 231                 }
 232                 /*
 233                  * AG inode header block
 234                  */
 235                 bp = xfs_buf_get(mp->m_ddev_targp,
 236                                  XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
 237                                  XFS_FSS_TO_BB(mp, 1), XBF_LOCK | XBF_MAPPED);
 238                 agi = XFS_BUF_TO_AGI(bp);
 239                 memset(agi, 0, mp->m_sb.sb_sectsize);
 240                 agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
 241                 agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
 242                 agi->agi_seqno = cpu_to_be32(agno);
 243                 agi->agi_length = cpu_to_be32(agsize);
 244                 agi->agi_count = 0;
 245                 agi->agi_root = cpu_to_be32(XFS_IBT_BLOCK(mp));
 246                 agi->agi_level = cpu_to_be32(1);
 247                 agi->agi_freecount = 0;
 248                 agi->agi_newino = cpu_to_be32(NULLAGINO);
 249                 agi->agi_dirino = cpu_to_be32(NULLAGINO);
 250                 for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
 251                         agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
 252                 error = xfs_bwrite(mp, bp);
 253                 if (error) {
 254                         goto error0;
 255                 }
 256                 /*
 257                  * BNO btree root block
 258                  */
 259                 bp = xfs_buf_get(mp->m_ddev_targp,
 260                                  XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
 261                                  BTOBB(mp->m_sb.sb_blocksize),
 262                                  XBF_LOCK | XBF_MAPPED);
 263                 block = XFS_BUF_TO_BLOCK(bp);
 264                 memset(block, 0, mp->m_sb.sb_blocksize);
 265                 block->bb_magic = cpu_to_be32(XFS_ABTB_MAGIC);
 266                 block->bb_level = 0;
 267                 block->bb_numrecs = cpu_to_be16(1);
 268                 block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
 269                 block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
 270                 arec = XFS_ALLOC_REC_ADDR(mp, block, 1);
 271                 arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
 272                 arec->ar_blockcount = cpu_to_be32(
 273                         agsize - be32_to_cpu(arec->ar_startblock));
 274                 error = xfs_bwrite(mp, bp);
 275                 if (error) {
 276                         goto error0;
 277                 }
 278                 /*
 279                  * CNT btree root block
 280                  */
 281                 bp = xfs_buf_get(mp->m_ddev_targp,
 282                                  XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
 283                                  BTOBB(mp->m_sb.sb_blocksize),
 284                                  XBF_LOCK | XBF_MAPPED);
 285                 block = XFS_BUF_TO_BLOCK(bp);
 286                 memset(block, 0, mp->m_sb.sb_blocksize);
 287                 block->bb_magic = cpu_to_be32(XFS_ABTC_MAGIC);
 288                 block->bb_level = 0;
 289                 block->bb_numrecs = cpu_to_be16(1);
 290                 block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
 291                 block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
 292                 arec = XFS_ALLOC_REC_ADDR(mp, block, 1);
 293                 arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
 294                 arec->ar_blockcount = cpu_to_be32(
 295                         agsize - be32_to_cpu(arec->ar_startblock));
 296                 nfree += be32_to_cpu(arec->ar_blockcount);
 297                 error = xfs_bwrite(mp, bp);
 298                 if (error) {
 299                         goto error0;
 300                 }
 301                 /*
 302                  * INO btree root block
 303                  */
 304                 bp = xfs_buf_get(mp->m_ddev_targp,
 305                                  XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
 306                                  BTOBB(mp->m_sb.sb_blocksize),
 307                                  XBF_LOCK | XBF_MAPPED);
 308                 block = XFS_BUF_TO_BLOCK(bp);
 309                 memset(block, 0, mp->m_sb.sb_blocksize);
 310                 block->bb_magic = cpu_to_be32(XFS_IBT_MAGIC);
 311                 block->bb_level = 0;
 312                 block->bb_numrecs = 0;
 313                 block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
 314                 block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
 315                 error = xfs_bwrite(mp, bp);
 316                 if (error) {
 317                         goto error0;
 318                 }
 319         }
 320         xfs_trans_agblocks_delta(tp, nfree);
 321         /*
 322          * There are new blocks in the old last a.g.
 323          */
 324         if (new) {
 325                 /*
 326                  * Change the agi length.
 327                  */
 328                 error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
 329                 if (error) {
 330                         goto error0;
 331                 }
 332                 ASSERT(bp);
 333                 agi = XFS_BUF_TO_AGI(bp);
 334                 be32_add_cpu(&agi->agi_length, new);
 335                 ASSERT(nagcount == oagcount ||
 336                        be32_to_cpu(agi->agi_length) == mp->m_sb.sb_agblocks);
 337                 xfs_ialloc_log_agi(tp, bp, XFS_AGI_LENGTH);
 338                 /*
 339                  * Change agf length.
 340                  */
 341                 error = xfs_alloc_read_agf(mp, tp, agno, 0, &bp);
 342                 if (error) {
 343                         goto error0;
 344                 }
 345                 ASSERT(bp);
 346                 agf = XFS_BUF_TO_AGF(bp);
 347                 be32_add_cpu(&agf->agf_length, new);
 348                 ASSERT(be32_to_cpu(agf->agf_length) ==
 349                        be32_to_cpu(agi->agi_length));
 350                 xfs_alloc_log_agf(tp, bp, XFS_AGF_LENGTH);
 351                 /*
 352                  * Free the new space.
 353                  */
 354                 error = xfs_free_extent(tp, XFS_AGB_TO_FSB(mp, agno,
 355                         be32_to_cpu(agf->agf_length) - new), new);
 356                 if (error) {
 357                         goto error0;
 358                 }
 359         }
 360         if (nagcount > oagcount)
 361                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);
 362         if (nb > mp->m_sb.sb_dblocks)
 363                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS,
 364                                  nb - mp->m_sb.sb_dblocks);
 365         if (nfree)
 366                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, nfree);
 367         if (dpct)
 368                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);
 369         error = xfs_trans_commit(tp, 0);
 370         if (error) {
 371                 return error;
 372         }
 373         /* New allocation groups fully initialized, so update mount struct */
 374         if (nagimax)
 375                 mp->m_maxagi = nagimax;
 376         if (mp->m_sb.sb_imax_pct) {
 377                 __uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct;
 378                 do_div(icount, 100);
 379                 mp->m_maxicount = icount << mp->m_sb.sb_inopblog;
 380         } else
 381                 mp->m_maxicount = 0;
 382         for (agno = 1; agno < nagcount; agno++) {
 383                 error = xfs_read_buf(mp, mp->m_ddev_targp,
 384                                   XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
 385                                   XFS_FSS_TO_BB(mp, 1), 0, &bp);
 386                 if (error) {
 387                         xfs_fs_cmn_err(CE_WARN, mp,
 388                         "error %d reading secondary superblock for ag %d",
 389                                 error, agno);
 390                         break;
 391                 }
 392                 xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb, XFS_SB_ALL_BITS);
 393                 /*
 394                  * If we get an error writing out the alternate superblocks,
 395                  * just issue a warning and continue.  The real work is
 396                  * already done and committed.
 397                  */
 398                 if (!(error = xfs_bwrite(mp, bp))) {
 399                         continue;
 400                 } else {
 401                         xfs_fs_cmn_err(CE_WARN, mp,
 402                 "write error %d updating secondary superblock for ag %d",
 403                                 error, agno);
 404                         break; /* no point in continuing */
 405                 }
 406         }
 407         return 0;
 408
 409  error0:
 410         xfs_trans_cancel(tp, XFS_TRANS_ABORT);
 411         return error;
 412 }
 413
 414 static int
 415 xfs_growfs_log_private(
 416         xfs_mount_t             *mp,    /* mount point for filesystem */
 417         xfs_growfs_log_t        *in)    /* growfs log input struct */
 418 {
 419         xfs_extlen_t            nb;
 420
 421         nb = in->newblocks;
 422         if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES))
 423                 return XFS_ERROR(EINVAL);
 424         if (nb == mp->m_sb.sb_logblocks &&
 425             in->isint == (mp->m_sb.sb_logstart != 0))
 426                 return XFS_ERROR(EINVAL);
 427         /*
 428          * Moving the log is hard, need new interfaces to sync
 429          * the log first, hold off all activity while moving it.
 430          * Can have shorter or longer log in the same space,
 431          * or transform internal to external log or vice versa.
 432          */
 433         return XFS_ERROR(ENOSYS);
 434 }
 435
 436 /*
 437  * protected versions of growfs function acquire and release locks on the mount
 438  * point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG,
 439  * XFS_IOC_FSGROWFSRT
 440  */
 441
 442
 443 int
 444 xfs_growfs_data(
 445         xfs_mount_t             *mp,
 446         xfs_growfs_data_t       *in)
 447 {
 448         int error;
 449
 450         if (!capable(CAP_SYS_ADMIN))
 451                 return XFS_ERROR(EPERM);
 452         if (!mutex_trylock(&mp->m_growlock))
 453                 return XFS_ERROR(EWOULDBLOCK);
 454         error = xfs_growfs_data_private(mp, in);
 455         mutex_unlock(&mp->m_growlock);
 456         return error;
 457 }
 458
 459 int
 460 xfs_growfs_log(
 461         xfs_mount_t             *mp,
 462         xfs_growfs_log_t        *in)
 463 {
 464         int error;
 465
 466         if (!capable(CAP_SYS_ADMIN))
 467                 return XFS_ERROR(EPERM);
 468         if (!mutex_trylock(&mp->m_growlock))
 469                 return XFS_ERROR(EWOULDBLOCK);
 470         error = xfs_growfs_log_private(mp, in);
 471         mutex_unlock(&mp->m_growlock);
 472         return error;
 473 }
 474
 475 /*
 476  * exported through ioctl XFS_IOC_FSCOUNTS
 477  */
 478
 479 int
 480 xfs_fs_counts(
 481         xfs_mount_t             *mp,
 482         xfs_fsop_counts_t       *cnt)
 483 {
 484         xfs_icsb_sync_counters(mp, XFS_ICSB_LAZY_COUNT);
 485         spin_lock(&mp->m_sb_lock);
 486         cnt->freedata = mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
 487         cnt->freertx = mp->m_sb.sb_frextents;
 488         cnt->freeino = mp->m_sb.sb_ifree;
 489         cnt->allocino = mp->m_sb.sb_icount;
 490         spin_unlock(&mp->m_sb_lock);
 491         return 0;
 492 }
 493
 494 /*
 495  * exported through ioctl XFS_IOC_SET_RESBLKS & XFS_IOC_GET_RESBLKS
 496  *
 497  * xfs_reserve_blocks is called to set m_resblks
 498  * in the in-core mount table. The number of unused reserved blocks
 499  * is kept in m_resblks_avail.
 500  *
 501  * Reserve the requested number of blocks if available. Otherwise return
 502  * as many as possible to satisfy the request. The actual number
 503  * reserved are returned in outval
 504  *
 505  * A null inval pointer indicates that only the current reserved blocks
 506  * available  should  be returned no settings are changed.
 507  */
 508
 509 int
 510 xfs_reserve_blocks(
 511         xfs_mount_t             *mp,
 512         __uint64_t              *inval,
 513         xfs_fsop_resblks_t      *outval)
 514 {
 515         __int64_t               lcounter, delta, fdblks_delta;
 516         __uint64_t              request;
 517
 518         /* If inval is null, report current values and return */
 519         if (inval == (__uint64_t *)NULL) {
 520                 if (!outval)
 521                         return EINVAL;
 522                 outval->resblks = mp->m_resblks;
 523                 outval->resblks_avail = mp->m_resblks_avail;
 524                 return 0;
 525         }
 526
 527         request = *inval;
 528
 529         /*
 530          * With per-cpu counters, this becomes an interesting
 531          * problem. we needto work out if we are freeing or allocation
 532          * blocks first, then we can do the modification as necessary.
 533          *
 534          * We do this under the m_sb_lock so that if we are near
 535          * ENOSPC, we will hold out any changes while we work out
 536          * what to do. This means that the amount of free space can
 537          * change while we do this, so we need to retry if we end up
 538          * trying to reserve more space than is available.
 539          *
 540          * We also use the xfs_mod_incore_sb() interface so that we
 541          * don't have to care about whether per cpu counter are
 542          * enabled, disabled or even compiled in....
 543          */
 544 retry:
 545         spin_lock(&mp->m_sb_lock);
 546         xfs_icsb_sync_counters_locked(mp, 0);
 547
 548         /*
 549          * If our previous reservation was larger than the current value,
 550          * then move any unused blocks back to the free pool.
 551          */
 552         fdblks_delta = 0;
 553         if (mp->m_resblks > request) {
 554                 lcounter = mp->m_resblks_avail - request;
 555                 if (lcounter  > 0) {            /* release unused blocks */
 556                         fdblks_delta = lcounter;
 557                         mp->m_resblks_avail -= lcounter;
 558                 }
 559                 mp->m_resblks = request;
 560         } else {
 561                 __int64_t       free;
 562
 563                 free =  mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
 564                 if (!free)
 565                         goto out; /* ENOSPC and fdblks_delta = 0 */
 566
 567                 delta = request - mp->m_resblks;
 568                 lcounter = free - delta;
 569                 if (lcounter < 0) {
 570                         /* We can't satisfy the request, just get what we can */
 571                         mp->m_resblks += free;
 572                         mp->m_resblks_avail += free;
 573                         fdblks_delta = -free;
 574                 } else {
 575                         fdblks_delta = -delta;
 576                         mp->m_resblks = request;
 577                         mp->m_resblks_avail += delta;
 578                 }
 579         }
 580 out:
 581         if (outval) {
 582                 outval->resblks = mp->m_resblks;
 583                 outval->resblks_avail = mp->m_resblks_avail;
 584         }
 585         spin_unlock(&mp->m_sb_lock);
 586
 587         if (fdblks_delta) {
 588                 /*
 589                  * If we are putting blocks back here, m_resblks_avail is
 590                  * already at its max so this will put it in the free pool.
 591                  *
 592                  * If we need space, we'll either succeed in getting it
 593                  * from the free block count or we'll get an enospc. If
 594                  * we get a ENOSPC, it means things changed while we were
 595                  * calculating fdblks_delta and so we should try again to
 596                  * see if there is anything left to reserve.
 597                  *
 598                  * Don't set the reserved flag here - we don't want to reserve
 599                  * the extra reserve blocks from the reserve.....
 600                  */
 601                 int error;
 602                 error = xfs_mod_incore_sb(mp, XFS_SBS_FDBLOCKS, fdblks_delta, 0);
 603                 if (error == ENOSPC)
 604                         goto retry;
 605         }
 606         return 0;
 607 }
 608
 609 int
 610 xfs_fs_log_dummy(
 611         xfs_mount_t     *mp)
 612 {
 613         xfs_trans_t     *tp;
 614         xfs_inode_t     *ip;
 615         int             error;
 616
 617         tp = _xfs_trans_alloc(mp, XFS_TRANS_DUMMY1, KM_SLEEP);
 618         error = xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0);
 619         if (error) {
 620                 xfs_trans_cancel(tp, 0);
 621                 return error;
 622         }
 623
 624         ip = mp->m_rootip;
 625         xfs_ilock(ip, XFS_ILOCK_EXCL);
 626
 627         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 628         xfs_trans_ihold(tp, ip);
 629         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 630         xfs_trans_set_sync(tp);
 631         error = xfs_trans_commit(tp, 0);
 632
 633         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 634         return error;
 635 }
 636
 637 int
 638 xfs_fs_goingdown(
 639         xfs_mount_t     *mp,
 640         __uint32_t      inflags)
 641 {
 642         switch (inflags) {
 643         case XFS_FSOP_GOING_FLAGS_DEFAULT: {
 644                 struct super_block *sb = freeze_bdev(mp->m_super->s_bdev);
 645
 646                 if (sb && !IS_ERR(sb)) {
 647                         xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
 648                         thaw_bdev(sb->s_bdev, sb);
 649                 }
 650
 651                 break;
 652         }
 653         case XFS_FSOP_GOING_FLAGS_LOGFLUSH:
 654                 xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
 655                 break;
 656         case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH:
 657                 xfs_force_shutdown(mp,
 658                                 SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR);
 659                 break;
 660         default:
 661                 return XFS_ERROR(EINVAL);
 662         }
 663
 664         return 0;
 665 }