Re: aligned_{u64,be64,le64} defined in #ifdef __KERNEL__

[Jan Engelhardt]

On Monday 2010-08-30 12:58, Andreas Gruenbacher wrote:
>
>> If we want a version of this type visible to userspace, it needs to,
>> for example, have double underscores prepended to the type name just
>> as we do for things like __u16 and __u32.
>
>How about something like this?


I like that approach:

>From 3bec018a4835d4fdbe35595366a51bd09e3cc1d0 Mon Sep 17 00:00:00 2001
>From: Andreas Gruenbacher <agruen@xxxxxxx>
>Date: Mon, 30 Aug 2010 12:51:01 +0200
>Subject: [PATCH] Define __aligned_{u64,le64,be64} types with 8-byte alignment
>
>Convert the existing #defines into typedefs, prepend two underscores to
>avoid POSIX namespace pollution, and expose the types to user space.
>
>These types are useful for enforcing the same alignment on 32-bit and
>64-bit architectures.  (Some 32-bit architectures only align 64-bit
>values on 4-byte boundaries by default.)
>
>(The aligned types are used by some netfilter user-space headers
>already.)
>
>Signed-off-by: Andreas Gruenbacher <agruen@xxxxxxx>
>---
> include/linux/if_ppp.h                    |   16 +++++++-------
> include/linux/netfilter/nfnetlink_log.h   |    4 +-
> include/linux/netfilter/nfnetlink_queue.h |    4 +-
> include/linux/netfilter/xt_connbytes.h    |    4 +-
> include/linux/netfilter/xt_quota.h        |    2 +-
> include/linux/types.h                     |   10 ++++----
> include/scsi/scsi_tgt_if.h                |   30 ++++++++++++++--------------
> include/xen/interface/hvm/hvm_op.h        |    2 +-
> 8 files changed, 36 insertions(+), 36 deletions(-)
>
>diff --git a/include/linux/if_ppp.h b/include/linux/if_ppp.h
>index fcef103..c9ad383 100644
>--- a/include/linux/if_ppp.h
>+++ b/include/linux/if_ppp.h
>@@ -114,14 +114,14 @@ struct pppol2tp_ioc_stats {
> 	__u16		tunnel_id;	/* redundant */
> 	__u16		session_id;	/* if zero, get tunnel stats */
> 	__u32		using_ipsec:1;	/* valid only for session_id == 0 */
>-	aligned_u64	tx_packets;
>-	aligned_u64	tx_bytes;
>-	aligned_u64	tx_errors;
>-	aligned_u64	rx_packets;
>-	aligned_u64	rx_bytes;
>-	aligned_u64	rx_seq_discards;
>-	aligned_u64	rx_oos_packets;
>-	aligned_u64	rx_errors;
>+	__aligned_u64	tx_packets;
>+	__aligned_u64	tx_bytes;
>+	__aligned_u64	tx_errors;
>+	__aligned_u64	rx_packets;
>+	__aligned_u64	rx_bytes;
>+	__aligned_u64	rx_seq_discards;
>+	__aligned_u64	rx_oos_packets;
>+	__aligned_u64	rx_errors;
--
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