fs/xfs/xfs_rw.c

   1 /*
   2  * Copyright (c) 2000-2003,2005 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_log.h"
  23 #include "xfs_inum.h"
  24 #include "xfs_trans.h"
  25 #include "xfs_sb.h"
  26 #include "xfs_ag.h"
  27 #include "xfs_dir.h"
  28 #include "xfs_dir2.h"
  29 #include "xfs_dmapi.h"
  30 #include "xfs_mount.h"
  31 #include "xfs_bmap_btree.h"
  32 #include "xfs_alloc_btree.h"
  33 #include "xfs_ialloc_btree.h"
  34 #include "xfs_dir_sf.h"
  35 #include "xfs_dir2_sf.h"
  36 #include "xfs_attr_sf.h"
  37 #include "xfs_dinode.h"
  38 #include "xfs_inode.h"
  39 #include "xfs_inode_item.h"
  40 #include "xfs_itable.h"
  41 #include "xfs_btree.h"
  42 #include "xfs_alloc.h"
  43 #include "xfs_ialloc.h"
  44 #include "xfs_attr.h"
  45 #include "xfs_bmap.h"
  46 #include "xfs_acl.h"
  47 #include "xfs_mac.h"
  48 #include "xfs_error.h"
  49 #include "xfs_buf_item.h"
  50 #include "xfs_rw.h"
  51
  52 /*
  53  * This is a subroutine for xfs_write() and other writers (xfs_ioctl)
  54  * which clears the setuid and setgid bits when a file is written.
  55  */
  56 int
  57 xfs_write_clear_setuid(
  58         xfs_inode_t     *ip)
  59 {
  60         xfs_mount_t     *mp;
  61         xfs_trans_t     *tp;
  62         int             error;
  63
  64         mp = ip->i_mount;
  65         tp = xfs_trans_alloc(mp, XFS_TRANS_WRITEID);
  66         if ((error = xfs_trans_reserve(tp, 0,
  67                                       XFS_WRITEID_LOG_RES(mp),
  68                                       0, 0, 0))) {
  69                 xfs_trans_cancel(tp, 0);
  70                 return error;
  71         }
  72         xfs_ilock(ip, XFS_ILOCK_EXCL);
  73         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
  74         xfs_trans_ihold(tp, ip);
  75         ip->i_d.di_mode &= ~S_ISUID;
  76
  77         /*
  78          * Note that we don't have to worry about mandatory
  79          * file locking being disabled here because we only
  80          * clear the S_ISGID bit if the Group execute bit is
  81          * on, but if it was on then mandatory locking wouldn't
  82          * have been enabled.
  83          */
  84         if (ip->i_d.di_mode & S_IXGRP) {
  85                 ip->i_d.di_mode &= ~S_ISGID;
  86         }
  87         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
  88         xfs_trans_set_sync(tp);
  89         error = xfs_trans_commit(tp, 0, NULL);
  90         xfs_iunlock(ip, XFS_ILOCK_EXCL);
  91         return 0;
  92 }
  93
  94 /*
  95  * Force a shutdown of the filesystem instantly while keeping
  96  * the filesystem consistent. We don't do an unmount here; just shutdown
  97  * the shop, make sure that absolutely nothing persistent happens to
  98  * this filesystem after this point.
  99  */
 100
 101 void
 102 xfs_do_force_shutdown(
 103         bhv_desc_t      *bdp,
 104         int             flags,
 105         char            *fname,
 106         int             lnnum)
 107 {
 108         int             logerror;
 109         xfs_mount_t     *mp;
 110
 111         mp = XFS_BHVTOM(bdp);
 112         logerror = flags & XFS_LOG_IO_ERROR;
 113
 114         if (!(flags & XFS_FORCE_UMOUNT)) {
 115                 cmn_err(CE_NOTE,
 116                 "xfs_force_shutdown(%s,0x%x) called from line %d of file %s.  Return address = 0x%p",
 117                         mp->m_fsname,flags,lnnum,fname,__return_address);
 118         }
 119         /*
 120          * No need to duplicate efforts.
 121          */
 122         if (XFS_FORCED_SHUTDOWN(mp) && !logerror)
 123                 return;
 124
 125         /*
 126          * This flags XFS_MOUNT_FS_SHUTDOWN, makes sure that we don't
 127          * queue up anybody new on the log reservations, and wakes up
 128          * everybody who's sleeping on log reservations and tells
 129          * them the bad news.
 130          */
 131         if (xfs_log_force_umount(mp, logerror))
 132                 return;
 133
 134         if (flags & XFS_CORRUPT_INCORE) {
 135                 xfs_cmn_err(XFS_PTAG_SHUTDOWN_CORRUPT, CE_ALERT, mp,
 136     "Corruption of in-memory data detected.  Shutting down filesystem: %s",
 137                         mp->m_fsname);
 138                 if (XFS_ERRLEVEL_HIGH <= xfs_error_level) {
 139                         xfs_stack_trace();
 140                 }
 141         } else if (!(flags & XFS_FORCE_UMOUNT)) {
 142                 if (logerror) {
 143                         xfs_cmn_err(XFS_PTAG_SHUTDOWN_LOGERROR, CE_ALERT, mp,
 144                         "Log I/O Error Detected.  Shutting down filesystem: %s",
 145                                 mp->m_fsname);
 146                 } else if (!(flags & XFS_SHUTDOWN_REMOTE_REQ)) {
 147                         xfs_cmn_err(XFS_PTAG_SHUTDOWN_IOERROR, CE_ALERT, mp,
 148                                 "I/O Error Detected.  Shutting down filesystem: %s",
 149                                 mp->m_fsname);
 150                 }
 151         }
 152         if (!(flags & XFS_FORCE_UMOUNT)) {
 153                 cmn_err(CE_ALERT,
 154                 "Please umount the filesystem, and rectify the problem(s)");
 155         }
 156 }
 157
 158
 159 /*
 160  * Called when we want to stop a buffer from getting written or read.
 161  * We attach the EIO error, muck with its flags, and call biodone
 162  * so that the proper iodone callbacks get called.
 163  */
 164 int
 165 xfs_bioerror(
 166         xfs_buf_t *bp)
 167 {
 168
 169 #ifdef XFSERRORDEBUG
 170         ASSERT(XFS_BUF_ISREAD(bp) || bp->b_iodone);
 171 #endif
 172
 173         /*
 174          * No need to wait until the buffer is unpinned.
 175          * We aren't flushing it.
 176          */
 177         xfs_buftrace("XFS IOERROR", bp);
 178         XFS_BUF_ERROR(bp, EIO);
 179         /*
 180          * We're calling biodone, so delete B_DONE flag. Either way
 181          * we have to call the iodone callback, and calling biodone
 182          * probably is the best way since it takes care of
 183          * GRIO as well.
 184          */
 185         XFS_BUF_UNREAD(bp);
 186         XFS_BUF_UNDELAYWRITE(bp);
 187         XFS_BUF_UNDONE(bp);
 188         XFS_BUF_STALE(bp);
 189
 190         XFS_BUF_CLR_BDSTRAT_FUNC(bp);
 191         xfs_biodone(bp);
 192
 193         return (EIO);
 194 }
 195
 196 /*
 197  * Same as xfs_bioerror, except that we are releasing the buffer
 198  * here ourselves, and avoiding the biodone call.
 199  * This is meant for userdata errors; metadata bufs come with
 200  * iodone functions attached, so that we can track down errors.
 201  */
 202 int
 203 xfs_bioerror_relse(
 204         xfs_buf_t *bp)
 205 {
 206         int64_t fl;
 207
 208         ASSERT(XFS_BUF_IODONE_FUNC(bp) != xfs_buf_iodone_callbacks);
 209         ASSERT(XFS_BUF_IODONE_FUNC(bp) != xlog_iodone);
 210
 211         xfs_buftrace("XFS IOERRELSE", bp);
 212         fl = XFS_BUF_BFLAGS(bp);
 213         /*
 214          * No need to wait until the buffer is unpinned.
 215          * We aren't flushing it.
 216          *
 217          * chunkhold expects B_DONE to be set, whether
 218          * we actually finish the I/O or not. We don't want to
 219          * change that interface.
 220          */
 221         XFS_BUF_UNREAD(bp);
 222         XFS_BUF_UNDELAYWRITE(bp);
 223         XFS_BUF_DONE(bp);
 224         XFS_BUF_STALE(bp);
 225         XFS_BUF_CLR_IODONE_FUNC(bp);
 226         XFS_BUF_CLR_BDSTRAT_FUNC(bp);
 227         if (!(fl & XFS_B_ASYNC)) {
 228                 /*
 229                  * Mark b_error and B_ERROR _both_.
 230                  * Lot's of chunkcache code assumes that.
 231                  * There's no reason to mark error for
 232                  * ASYNC buffers.
 233                  */
 234                 XFS_BUF_ERROR(bp, EIO);
 235                 XFS_BUF_V_IODONESEMA(bp);
 236         } else {
 237                 xfs_buf_relse(bp);
 238         }
 239         return (EIO);
 240 }
 241 /*
 242  * Prints out an ALERT message about I/O error.
 243  */
 244 void
 245 xfs_ioerror_alert(
 246         char                    *func,
 247         struct xfs_mount        *mp,
 248         xfs_buf_t               *bp,
 249         xfs_daddr_t             blkno)
 250 {
 251         cmn_err(CE_ALERT,
 252  "I/O error in filesystem (\"%s\") meta-data dev %s block 0x%llx"
 253  "       (\"%s\") error %d buf count %zd",
 254                 (!mp || !mp->m_fsname) ? "(fs name not set)" : mp->m_fsname,
 255                 XFS_BUFTARG_NAME(bp->pb_target),
 256                 (__uint64_t)blkno,
 257                 func,
 258                 XFS_BUF_GETERROR(bp),
 259                 XFS_BUF_COUNT(bp));
 260 }
 261
 262 /*
 263  * This isn't an absolute requirement, but it is
 264  * just a good idea to call xfs_read_buf instead of
 265  * directly doing a read_buf call. For one, we shouldn't
 266  * be doing this disk read if we are in SHUTDOWN state anyway,
 267  * so this stops that from happening. Secondly, this does all
 268  * the error checking stuff and the brelse if appropriate for
 269  * the caller, so the code can be a little leaner.
 270  */
 271
 272 int
 273 xfs_read_buf(
 274         struct xfs_mount *mp,
 275         xfs_buftarg_t    *target,
 276         xfs_daddr_t      blkno,
 277         int              len,
 278         uint             flags,
 279         xfs_buf_t        **bpp)
 280 {
 281         xfs_buf_t        *bp;
 282         int              error;
 283
 284         if (flags)
 285                 bp = xfs_buf_read_flags(target, blkno, len, flags);
 286         else
 287                 bp = xfs_buf_read(target, blkno, len, flags);
 288         if (!bp)
 289                 return XFS_ERROR(EIO);
 290         error = XFS_BUF_GETERROR(bp);
 291         if (bp && !error && !XFS_FORCED_SHUTDOWN(mp)) {
 292                 *bpp = bp;
 293         } else {
 294                 *bpp = NULL;
 295                 if (error) {
 296                         xfs_ioerror_alert("xfs_read_buf", mp, bp, XFS_BUF_ADDR(bp));
 297                 } else {
 298                         error = XFS_ERROR(EIO);
 299                 }
 300                 if (bp) {
 301                         XFS_BUF_UNDONE(bp);
 302                         XFS_BUF_UNDELAYWRITE(bp);
 303                         XFS_BUF_STALE(bp);
 304                         /*
 305                          * brelse clears B_ERROR and b_error
 306                          */
 307                         xfs_buf_relse(bp);
 308                 }
 309         }
 310         return (error);
 311 }
 312
 313 /*
 314  * Wrapper around bwrite() so that we can trap
 315  * write errors, and act accordingly.
 316  */
 317 int
 318 xfs_bwrite(
 319         struct xfs_mount *mp,
 320         struct xfs_buf   *bp)
 321 {
 322         int     error;
 323
 324         /*
 325          * XXXsup how does this work for quotas.
 326          */
 327         XFS_BUF_SET_BDSTRAT_FUNC(bp, xfs_bdstrat_cb);
 328         XFS_BUF_SET_FSPRIVATE3(bp, mp);
 329         XFS_BUF_WRITE(bp);
 330
 331         if ((error = XFS_bwrite(bp))) {
 332                 ASSERT(mp);
 333                 /*
 334                  * Cannot put a buftrace here since if the buffer is not
 335                  * B_HOLD then we will brelse() the buffer before returning
 336                  * from bwrite and we could be tracing a buffer that has
 337                  * been reused.
 338                  */
 339                 xfs_force_shutdown(mp, XFS_METADATA_IO_ERROR);
 340         }
 341         return (error);
 342 }