Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 7306006f authored by H. Peter Anvin's avatar H. Peter Anvin
Browse files

x86, realmode: Pointer walk cleanups, pull out invariant use of __pa() 



The pointer arithmetic in this function was really bizarre, where in
fact all we really wanted was a simple pointer array walk.  Use the
much more idiomatic construction for that (*ptr++).

Factor an invariant use of __pa() out of the relocation loop.  At
least on 64 bits it seems gcc isn't capable of doing that
automatically.

Change the scope of a couple of variables to make it extra obvious
that they are extremely local temp variables.

Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-rd908t9c8kvcojdabtmm94mb@git.kernel.org
parent d8af4ce4

arch/x86/realmode/init.c

+12 −14
Original line number Diff line number Diff line
@@ -29,12 +29,10 @@ void __init reserve_real_mode(void) 
void __init setup_real_mode(void)

{

	u16 real_mode_seg;

	u32 *rel;

	const u32 *rel;

	u32 count;

	u32 *ptr;

	u16 *seg;

	int i;

	unsigned char *base;

	unsigned long phys_base;

	struct trampoline_header *trampoline_header;

	size_t size = PAGE_ALIGN(real_mode_blob_end - real_mode_blob);

#ifdef CONFIG_X86_64
@@ -46,23 +44,23 @@ void __init setup_real_mode(void) 


	memcpy(base, real_mode_blob, size);



	real_mode_seg = __pa(base) >> 4;

	phys_base = __pa(base);

	real_mode_seg = phys_base >> 4;



	rel = (u32 *) real_mode_relocs;



	/* 16-bit segment relocations. */

	count = rel[0];

	rel = &rel[1];

	for (i = 0; i < count; i++) {

		seg = (u16 *) (base + rel[i]);

	count = *rel++;

	while (count--) {

		u16 *seg = (u16 *) (base + *rel++);

		*seg = real_mode_seg;

	}



	/* 32-bit linear relocations. */

	count = rel[i];

	rel =  &rel[i + 1];

	for (i = 0; i < count; i++) {

		ptr = (u32 *) (base + rel[i]);

		*ptr += __pa(base);

	count = *rel++;

	while (count--) {

		u32 *ptr = (u32 *) (base + *rel++);

		*ptr += phys_base;

	}



	/* Must be perfomed *after* relocation. */