Re: [PATCH] diskquota: 32bit quota tools on 64bit architectures

From: Arnd Bergmann
Date: Wed Oct 25 2006 - 07:04:50 EST


On Wednesday 25 October 2006 12:03, Vasily Tarasov wrote:
> + * This code works only for 32 bit quota tools over 64 bit OS (x86_64, ia64)
> + * and is necessary due to alignment problems.
> + */
> +struct compat_if_dqblk {
> +       compat_uint_t dqb_bhardlimit[2];
> +       compat_uint_t dqb_bsoftlimit[2];
> +       compat_uint_t dqb_curspace[2];
> +       compat_uint_t dqb_ihardlimit[2];
> +       compat_uint_t dqb_isoftlimit[2];
> +       compat_uint_t dqb_curinodes[2];
> +       compat_uint_t dqb_btime[2];
> +       compat_uint_t dqb_itime[2];
> +       compat_uint_t dqb_valid;
> +};
> +
> +/* XFS structures */
> +struct compat_fs_qfilestat {
> +       compat_uint_t dqb_bhardlimit[2];
> +       compat_uint_t   qfs_nblks[2];
> +       compat_uint_t   qfs_nextents;
> +};
> +

The patch looks technically correct, but you have defined the structures
in a somewhat unusual way. I'd have defined them with
attribute((packed, aligned(4))) in the end.

Or even better, we should probably add a

typedef unsigned long long __attribute__((aligned(4))) compat_u64;

for x86 compat and use that instead of compat_uint_t foo[2].

Arnd <><
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/