alistair23-linux/arch/um/include/shared/user.h
Geert Uytterhoeven 9429ec96c2 um: Preinclude include/linux/kern_levels.h
The userspace part of UML uses the asm-offsets.h generator mechanism to
create definitions for UM_KERN_<LEVEL> that match the in-kernel
KERN_<LEVEL> constant definitions.

As of commit 04d2c8c83d ("printk: convert
the format for KERN_<LEVEL> to a 2 byte pattern"), KERN_<LEVEL> is no
longer expanded to the literal '"<LEVEL>"', but to '"\001" "LEVEL"', i.e.
it contains two parts.

However, the combo of DEFINE_STR() in
arch/x86/um/shared/sysdep/kernel-offsets.h and sed-y in Kbuild doesn't
support string literals consisting of multiple parts. Hence for all
UM_KERN_<LEVEL> definitions, only the SOH character is retained in the actual
definition, while the remainder ends up in the comment. E.g. in
include/generated/asm-offsets.h we get

    #define UM_KERN_INFO "\001" /* "6" KERN_INFO */

instead of

    #define UM_KERN_INFO "\001" "6" /* KERN_INFO */

This causes spurious '^A' output in some kernel messages:

    Calibrating delay loop... 4640.76 BogoMIPS (lpj=23203840)
    pid_max: default: 32768 minimum: 301
    Mount-cache hash table entries: 256
    ^AChecking that host ptys support output SIGIO...Yes
    ^AChecking that host ptys support SIGIO on close...No, enabling workaround
    ^AUsing 2.6 host AIO
    NET: Registered protocol family 16
    bio: create slab <bio-0> at 0
    Switching to clocksource itimer

To fix this:
  - Move the mapping from UM_KERN_<LEVEL> to KERN_<LEVEL> from
    arch/um/include/shared/common-offsets.h to
    arch/um/include/shared/user.h, which is preincluded for all userspace
    parts,
  - Preinclude include/linux/kern_levels.h for all userspace parts, to
    obtain the in-kernel KERN_<LEVEL> constant definitions. This doesn't
    violate the kernel/userspace separation, as include/linux/kern_levels.h
    is self-contained and doesn't expose any other kernel internals.
  - Remove the now unused STR() and DEFINE_STR() macros.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-09-27 20:20:09 +02:00

58 lines
1.5 KiB
C

/*
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#ifndef __USER_H__
#define __USER_H__
#include <generated/asm-offsets.h>
/*
* The usual definition - copied here because the kernel provides its own,
* fancier, type-safe, definition. Using that one would require
* copying too much infrastructure for my taste, so userspace files
* get less checking than kernel files.
*/
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
/* This is to get size_t */
#ifdef __KERNEL__
#include <linux/types.h>
#else
#include <stddef.h>
#endif
extern void panic(const char *fmt, ...)
__attribute__ ((format (printf, 1, 2)));
/* Requires preincluding include/linux/kern_levels.h */
#define UM_KERN_EMERG KERN_EMERG
#define UM_KERN_ALERT KERN_ALERT
#define UM_KERN_CRIT KERN_CRIT
#define UM_KERN_ERR KERN_ERR
#define UM_KERN_WARNING KERN_WARNING
#define UM_KERN_NOTICE KERN_NOTICE
#define UM_KERN_INFO KERN_INFO
#define UM_KERN_DEBUG KERN_DEBUG
#define UM_KERN_CONT KERN_CONT
#ifdef UML_CONFIG_PRINTK
extern int printk(const char *fmt, ...)
__attribute__ ((format (printf, 1, 2)));
#else
static inline int printk(const char *fmt, ...)
{
return 0;
}
#endif
extern int in_aton(char *str);
extern size_t strlcpy(char *, const char *, size_t);
extern size_t strlcat(char *, const char *, size_t);
/* Copied from linux/compiler-gcc.h since we can't include it directly */
#define barrier() __asm__ __volatile__("": : :"memory")
#endif