Re: Diskfs Questions

[Marcus Brinkmann]

On Fri, Jun 28, 2002 at 04:20:43PM -0530, sajith@mec.ac.in wrote:
> struct jfs_superblock *jfs_sb;
> struct user_pager_info *upi;
> struct port_bucket *pager_bucket;
> [..]
> 
> diskfs_start_disk_pager (upi, pager_bucket, 1, store->size,
>                         &disk_image);
> jfs_sb = (struct jfs_superblock *) ((char *)disk_image + SUPER1_OFF);
> printf ("jfs_sb->s_magic : %s\n", jfs_sb->s_magic);
> 
> With the last printf, translator crashes with this message:
> 
> jfs_sb->s_magic ./my_jfs: BUG: unexpected fault on disk image (10,
> 0x10053000) in [0x1004b000,0x305fb600) eip 0x112d2de err 0xa.

The first thing to make sure is that
SUPER1_OFF + offsetof (jfs_sb,s_magic) + sizeof (jfs_sb->s_magic) - 1
is smaller than store->size of course.

> We haven't implemented all callbacks, could that be the problem?

You must have the pager_read_page callback at least for the disk pager
to get this working.
 
Thanks,
Marcus

-- 
`Rhubarb is no Egyptian god.' Debian http://www.debian.org brinkmd@debian.org
Marcus Brinkmann              GNU    http://www.gnu.org    marcus@gnu.org
Marcus.Brinkmann@ruhr-uni-bochum.de
http://www.marcus-brinkmann.de