src/patches/suse-2.6.27.25/patches.suse/ext2-fsync-err

   1 From: Chris Mason <mason@suse.com>
   2 Subject: ext2 should force the FS readonly for metadata write errors
   3 References: 65718
   4
   5 During fsync we should check for write errors to the block device in order to make
   6 sure all metadata writes have been properly written to the disk.  Without this check
   7 writes that happen through the normal async mechanisms might hit errors without
   8 reporting them back to the application.
   9
  10 Acked-by: Jeff Mahoney <jeffm@suse.com>
  11
  12 ---
  13  fs/ext2/fsync.c |   17 +++++++++++++++++
  14  1 file changed, 17 insertions(+)
  15
  16 --- a/fs/ext2/fsync.c
  17 +++ b/fs/ext2/fsync.c
  18 @@ -24,6 +24,7 @@
  19
  20  #include "ext2.h"
  21  #include <linux/buffer_head.h>         /* for sync_mapping_buffers() */
  22 +#include <linux/pagemap.h>
  23
  24
  25  /*
  26 @@ -34,10 +35,26 @@
  27  int ext2_sync_file(struct file *file, struct dentry *dentry, int datasync)
  28  {
  29         struct inode *inode = dentry->d_inode;
  30 +       struct super_block *sb = inode->i_sb;
  31         int err;
  32         int ret;
  33
  34         ret = sync_mapping_buffers(inode->i_mapping);
  35 +
  36 +       /* it might make more sense to ext2_error on -EIO from
  37 +        * sync_mapping_buffers as well, but those errors are isolated to just
  38 +        * this file. We can safely return -EIO to fsync and let the app know
  39 +        * they have a problem.
  40 +        *
  41 +        * AS_EIO indicates a failure to write a metadata page, but we have no
  42 +        * way of knowing which one.  It's best to force readonly and let fsck
  43 +        * figure it all out.
  44 +        */
  45 +       if (test_and_clear_bit(AS_EIO, &sb->s_bdev->bd_inode->i_mapping->flags)) {
  46 +               ext2_error(sb, "ext2_sync_file", "metadata io error");
  47 +               if (!ret)
  48 +                       ret = -EIO;
  49 +       }
  50         if (!(inode->i_state & I_DIRTY))
  51                 return ret;
  52         if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))