um: Add os_info() for pre-boot information messages

Add os_info() for printing out pre-boot information
level messages in stderr. The messages via os_info()
are suppressed by "quiet" kernel command line.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Masami Hiramatsu 2017-05-18 02:16:05 +09:00 committed by Richard Weinberger
parent e03c78ac2d
commit f7887ee110
2 changed files with 27 additions and 0 deletions

View File

@ -242,6 +242,8 @@ extern void setup_hostinfo(char *buf, int len);
extern void os_dump_core(void) __attribute__ ((noreturn));
extern void um_early_printk(const char *s, unsigned int n);
extern void os_fix_helper_signals(void);
extern void os_info(const char *fmt, ...)
__attribute__ ((format (printf, 1, 2)));
/* time.c */
extern void os_idle_sleep(unsigned long long nsecs);

View File

@ -13,6 +13,7 @@
#include <wait.h>
#include <sys/mman.h>
#include <sys/utsname.h>
#include <init.h>
#include <os.h>
void stack_protections(unsigned long address)
@ -152,3 +153,27 @@ void um_early_printk(const char *s, unsigned int n)
{
printf("%.*s", n, s);
}
static int quiet_info;
static int __init quiet_cmd_param(char *str, int *add)
{
quiet_info = 1;
return 0;
}
__uml_setup("quiet", quiet_cmd_param,
"quiet\n"
" Turns off information messages during boot.\n\n");
void os_info(const char *fmt, ...)
{
va_list list;
if (quiet_info)
return;
va_start(list, fmt);
vfprintf(stderr, fmt, list);
va_end(list);
}