linux-stable/arch/powerpc/include/asm/fixmap.h
Christophe Leroy 4cfac2f9c7 powerpc/mm: Simplify __set_fixmap()
__set_fixmap() uses __fix_to_virt() then does the boundary checks
by it self. Instead, we can use fix_to_virt() which does the
verification at build time. For this, we need to use it inline
so that GCC can see the real value of idx at buildtime.

In the meantime, we remove the 'fixmaps' variable.
This variable is set but has never been used from the beginning
(commit 2c419bdeca ("[POWERPC] Port fixmap from x86 and use
for kmap_atomic"))

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:58 +10:00

80 lines
2.3 KiB
C

/*
* fixmap.h: compile-time virtual memory allocation
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1998 Ingo Molnar
*
* Copyright 2008 Freescale Semiconductor Inc.
* Port to powerpc added by Kumar Gala
*/
#ifndef _ASM_FIXMAP_H
#define _ASM_FIXMAP_H
#ifndef __ASSEMBLY__
#include <linux/kernel.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#ifdef CONFIG_HIGHMEM
#include <linux/threads.h>
#include <asm/kmap_types.h>
#endif
#define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE))
/*
* Here we define all the compile-time 'special' virtual
* addresses. The point is to have a constant address at
* compile time, but to set the physical address only
* in the boot process. We allocate these special addresses
* from the end of virtual memory (0xfffff000) backwards.
* Also this lets us do fail-safe vmalloc(), we
* can guarantee that these special addresses and
* vmalloc()-ed addresses never overlap.
*
* these 'compile-time allocated' memory buffers are
* fixed-size 4k pages. (or larger if used with an increment
* highger than 1) use fixmap_set(idx,phys) to associate
* physical memory with fixmap indices.
*
* TLB entries of such buffers will not be flushed across
* task switches.
*/
enum fixed_addresses {
FIX_HOLE,
/* reserve the top 128K for early debugging purposes */
FIX_EARLY_DEBUG_TOP = FIX_HOLE,
FIX_EARLY_DEBUG_BASE = FIX_EARLY_DEBUG_TOP+((128*1024)/PAGE_SIZE)-1,
#ifdef CONFIG_HIGHMEM
FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
#endif
#ifdef CONFIG_PPC_8xx
/* For IMMR we need an aligned 512K area */
#define FIX_IMMR_SIZE (512 * 1024 / PAGE_SIZE)
FIX_IMMR_START,
FIX_IMMR_BASE = __ALIGN_MASK(FIX_IMMR_START, FIX_IMMR_SIZE - 1) - 1 +
FIX_IMMR_SIZE,
#endif
/* FIX_PCIE_MCFG, */
__end_of_fixed_addresses
};
#define __FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
#define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE)
#define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NCG
#include <asm-generic/fixmap.h>
static inline void __set_fixmap(enum fixed_addresses idx,
phys_addr_t phys, pgprot_t flags)
{
map_kernel_page(fix_to_virt(idx), phys, pgprot_val(flags));
}
#endif /* !__ASSEMBLY__ */
#endif