@@ -15,39 +15,33 @@ asm (
" .text \n"
" .globl _start \n"
"_start: \n"
- " call 1f \n"
- "1: pop %ebx \n"
- " mov %eax,alloc-1b(%ebx) \n"
- " jmp reloc \n"
- );
-
-/*
- * This is our data. Because the code must be relocatable, no BSS is
- * allowed. All data is accessed PC-relative with inline assembly.
- */
-asm (
- "alloc: \n"
- " .long 0 \n"
+ " push %eax \n"
+ " push 0x8(%esp) \n"
+ " call reloc \n"
+ " ret $0x4 \n"
);
typedef unsigned int u32;
#include "../../../include/xen/multiboot.h"
+#define __stdcall __attribute__((__stdcall__))
+
+#define ALIGN_UP(arg, align) \
+ (((arg) + (align) - 1) & ~((typeof(arg))(align) - 1))
+
+static u32 alloc;
+
static void *reloc_mbi_struct(void *old, unsigned int bytes)
{
void *new;
- asm(
- " call 1f \n"
- "1: pop %%edx \n"
- " mov alloc-1b(%%edx),%0 \n"
- " sub %1,%0 \n"
- " and $~15,%0 \n"
- " mov %0,alloc-1b(%%edx) \n"
- " mov %0,%%edi \n"
- " rep movsb \n"
- : "=&r" (new), "+c" (bytes), "+S" (old)
- : : "edx", "edi", "memory");
- return new;
+
+ alloc -= ALIGN_UP(bytes, 16);
+ new = (void *)alloc;
+
+ while ( bytes-- )
+ *(char *)new++ = *(char *)old++;
+
+ return (void *)alloc;
}
static char *reloc_mbi_string(char *old)
@@ -58,11 +52,15 @@ static char *reloc_mbi_string(char *old)
return reloc_mbi_struct(old, p - old + 1);
}
-multiboot_info_t *reloc(multiboot_info_t *mbi_old)
+multiboot_info_t __stdcall *reloc(multiboot_info_t *mbi_old, u32 trampoline)
{
- multiboot_info_t *mbi = reloc_mbi_struct(mbi_old, sizeof(*mbi));
+ multiboot_info_t *mbi;
int i;
+ alloc = trampoline;
+
+ mbi = reloc_mbi_struct(mbi_old, sizeof(*mbi));
+
if ( mbi->flags & MBI_CMDLINE )
mbi->cmdline = (u32)reloc_mbi_string((char *)mbi->cmdline);
..to increase code readability and ease its maintenance. Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com> --- v5 - suggestions/fixes: - improve commit message (suggested by Jan Beulich). --- xen/arch/x86/boot/reloc.c | 52 ++++++++++++++++++++++----------------------- 1 file changed, 25 insertions(+), 27 deletions(-)