fs/xfs/xfs_rw.c

   1 /*
   2  * Copyright (c) 2000-2006 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_mount.h"
  28 #include "xfs_bmap_btree.h"
  29 #include "xfs_dinode.h"
  30 #include "xfs_inode.h"
  31 #include "xfs_error.h"
  32 #include "xfs_rw.h"
  33
  34 /*
  35  * Force a shutdown of the filesystem instantly while keeping
  36  * the filesystem consistent. We don't do an unmount here; just shutdown
  37  * the shop, make sure that absolutely nothing persistent happens to
  38  * this filesystem after this point.
  39  */
  40 void
  41 xfs_do_force_shutdown(
  42         xfs_mount_t     *mp,
  43         int             flags,
  44         char            *fname,
  45         int             lnnum)
  46 {
  47         int             logerror;
  48
  49         logerror = flags & SHUTDOWN_LOG_IO_ERROR;
  50
  51         if (!(flags & SHUTDOWN_FORCE_UMOUNT)) {
  52                 xfs_notice(mp,
  53         "%s(0x%x) called from line %d of file %s.  Return address = 0x%p",
  54                         __func__, flags, lnnum, fname, __return_address);
  55         }
  56         /*
  57          * No need to duplicate efforts.
  58          */
  59         if (XFS_FORCED_SHUTDOWN(mp) && !logerror)
  60                 return;
  61
  62         /*
  63          * This flags XFS_MOUNT_FS_SHUTDOWN, makes sure that we don't
  64          * queue up anybody new on the log reservations, and wakes up
  65          * everybody who's sleeping on log reservations to tell them
  66          * the bad news.
  67          */
  68         if (xfs_log_force_umount(mp, logerror))
  69                 return;
  70
  71         if (flags & SHUTDOWN_CORRUPT_INCORE) {
  72                 xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_CORRUPT,
  73     "Corruption of in-memory data detected.  Shutting down filesystem");
  74                 if (XFS_ERRLEVEL_HIGH <= xfs_error_level)
  75                         xfs_stack_trace();
  76         } else if (!(flags & SHUTDOWN_FORCE_UMOUNT)) {
  77                 if (logerror) {
  78                         xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_LOGERROR,
  79                 "Log I/O Error Detected.  Shutting down filesystem");
  80                 } else if (flags & SHUTDOWN_DEVICE_REQ) {
  81                         xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_IOERROR,
  82                 "All device paths lost.  Shutting down filesystem");
  83                 } else if (!(flags & SHUTDOWN_REMOTE_REQ)) {
  84                         xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_IOERROR,
  85                 "I/O Error Detected. Shutting down filesystem");
  86                 }
  87         }
  88         if (!(flags & SHUTDOWN_FORCE_UMOUNT)) {
  89                 xfs_alert(mp,
  90         "Please umount the filesystem and rectify the problem(s)");
  91         }
  92 }
  93
  94 /*
  95  * This isn't an absolute requirement, but it is
  96  * just a good idea to call xfs_read_buf instead of
  97  * directly doing a read_buf call. For one, we shouldn't
  98  * be doing this disk read if we are in SHUTDOWN state anyway,
  99  * so this stops that from happening. Secondly, this does all
 100  * the error checking stuff and the brelse if appropriate for
 101  * the caller, so the code can be a little leaner.
 102  */
 103
 104 int
 105 xfs_read_buf(
 106         struct xfs_mount *mp,
 107         xfs_buftarg_t    *target,
 108         xfs_daddr_t      blkno,
 109         int              len,
 110         uint             flags,
 111         xfs_buf_t        **bpp)
 112 {
 113         xfs_buf_t        *bp;
 114         int              error;
 115
 116         if (!flags)
 117                 flags = XBF_LOCK | XBF_MAPPED;
 118
 119         bp = xfs_buf_read(target, blkno, len, flags);
 120         if (!bp)
 121                 return XFS_ERROR(EIO);
 122         error = bp->b_error;
 123         if (!error && !XFS_FORCED_SHUTDOWN(mp)) {
 124                 *bpp = bp;
 125         } else {
 126                 *bpp = NULL;
 127                 if (error) {
 128                         xfs_buf_ioerror_alert(bp, __func__);
 129                 } else {
 130                         error = XFS_ERROR(EIO);
 131                 }
 132                 if (bp) {
 133                         XFS_BUF_UNDONE(bp);
 134                         xfs_buf_stale(bp);
 135                         /*
 136                          * brelse clears B_ERROR and b_error
 137                          */
 138                         xfs_buf_relse(bp);
 139                 }
 140         }
 141         return (error);
 142 }
 143
 144 /*
 145  * helper function to extract extent size hint from inode
 146  */
 147 xfs_extlen_t
 148 xfs_get_extsz_hint(
 149         struct xfs_inode        *ip)
 150 {
 151         if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
 152                 return ip->i_d.di_extsize;
 153         if (XFS_IS_REALTIME_INODE(ip))
 154                 return ip->i_mount->m_sb.sb_rextsize;
 155         return 0;
 156 }