Commit ab893fb9 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Catalin Marinas
Browse files

arm64: introduce KIMAGE_VADDR as the virtual base of the kernel region 



This introduces the preprocessor symbol KIMAGE_VADDR which will serve as
the symbolic virtual base of the kernel region, i.e., the kernel's virtual
offset will be KIMAGE_VADDR + TEXT_OFFSET. For now, we define it as being
equal to PAGE_OFFSET, but in the future, it will be moved below it once
we move the kernel virtual mapping out of the linear mapping.

Reviewed-by: default avatarMark Rutland <mark.rutland@arm.com>
Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 324420bf

arch/arm64/include/asm/memory.h

+8 −2
Original line number Diff line number Diff line
@@ -51,7 +51,8 @@ 
#define VA_BITS			(CONFIG_ARM64_VA_BITS)

#define VA_START		(UL(0xffffffffffffffff) << VA_BITS)

#define PAGE_OFFSET		(UL(0xffffffffffffffff) << (VA_BITS - 1))

#define MODULES_END		(PAGE_OFFSET)

#define KIMAGE_VADDR		(PAGE_OFFSET)

#define MODULES_END		(KIMAGE_VADDR)

#define MODULES_VADDR		(MODULES_END - SZ_64M)

#define PCI_IO_END		(MODULES_VADDR - SZ_2M)

#define PCI_IO_START		(PCI_IO_END - PCI_IO_SIZE)
@@ -75,8 +76,13 @@ 
 * private definitions which should NOT be used outside memory.h

 * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.

 */

#define __virt_to_phys(x)	(((phys_addr_t)(x) - PAGE_OFFSET + PHYS_OFFSET))

#define __virt_to_phys(x) ({						\

	phys_addr_t __x = (phys_addr_t)(x);				\

	__x >= PAGE_OFFSET ? (__x - PAGE_OFFSET + PHYS_OFFSET) :	\

			     (__x - KIMAGE_VADDR + PHYS_OFFSET); })



#define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET + PAGE_OFFSET))

#define __phys_to_kimg(x)	((unsigned long)((x) - PHYS_OFFSET + KIMAGE_VADDR))



/*

 * Convert a page to/from a physical address

arch/arm64/kernel/head.S

+1 −1
Original line number Diff line number Diff line
@@ -389,7 +389,7 @@ __create_page_tables: 
	 * Map the kernel image (starting with PHYS_OFFSET).

	 */

	mov	x0, x26				// swapper_pg_dir

	mov	x5, #PAGE_OFFSET

	ldr	x5, =KIMAGE_VADDR

	create_pgd_entry x0, x5, x3, x6

	ldr	x6, =KERNEL_END			// __va(KERNEL_END)

	mov	x3, x24				// phys offset

arch/arm64/kernel/vmlinux.lds.S

+2 −2
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ SECTIONS 
		*(.discard.*)

	}



	. = PAGE_OFFSET + TEXT_OFFSET;

	. = KIMAGE_VADDR + TEXT_OFFSET;



	.head.text : {

		_text = .;
@@ -186,4 +186,4 @@ ASSERT(__idmap_text_end - (__idmap_text_start & ~(SZ_4K - 1)) <= SZ_4K, 
/*

 * If padding is applied before .head.text, virt<->phys conversions will fail.

 */

ASSERT(_text == (PAGE_OFFSET + TEXT_OFFSET), "HEAD is misaligned")
 
ASSERT(_text == (KIMAGE_VADDR + TEXT_OFFSET), "HEAD is misaligned")

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