x86, boot: Add get_cmd_line_ptr()
Add an accessor function for the command line address.
Later we will add support for holding a 64-bit address via ext_cmd_line_ptr.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1359058816-7615-17-git-send-email-yinghai@kernel.org
Cc: Gokul Caushik <caushik1@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Joe Millenbach <jmillenbach@gmail.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index b88a1fa..62c8ce4 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -112,14 +112,23 @@
(unsigned long) __bss_stop - (unsigned long) __bss_start);
}
+static unsigned long get_cmd_line_ptr(void)
+{
+ unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
+
+ return cmd_line_ptr;
+}
+
static void __init copy_bootdata(char *real_mode_data)
{
char * command_line;
+ unsigned long cmd_line_ptr;
memcpy(&boot_params, real_mode_data, sizeof boot_params);
sanitize_boot_params(&boot_params);
- if (boot_params.hdr.cmd_line_ptr) {
- command_line = __va(boot_params.hdr.cmd_line_ptr);
+ cmd_line_ptr = get_cmd_line_ptr();
+ if (cmd_line_ptr) {
+ command_line = __va(cmd_line_ptr);
memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
}
}
