Commit 2a15ba82 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

ARM: highmem: Switch to generic kmap atomic 



No reason having the same code in every architecture.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201103095857.582196476@linutronix.de
parent 39cac191

arch/arm/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -1498,6 +1498,7 @@ config HAVE_ARCH_PFN_VALID 
config HIGHMEM

	bool "High Memory Support"

	depends on MMU

	select KMAP_LOCAL

	help

	  The address space of ARM processors is only 4 Gigabytes large

	  and it has to accommodate user address space, kernel address

arch/arm/include/asm/fixmap.h

+2 −2
Original line number Diff line number Diff line
@@ -7,14 +7,14 @@ 
#define FIXADDR_TOP		(FIXADDR_END - PAGE_SIZE)



#include <linux/pgtable.h>

#include <asm/kmap_types.h>

#include <asm/kmap_size.h>



enum fixed_addresses {

	FIX_EARLYCON_MEM_BASE,

	__end_of_permanent_fixed_addresses,



	FIX_KMAP_BEGIN = __end_of_permanent_fixed_addresses,

	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,

	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,



	/* Support writing RO kernel text via kprobes, jump labels, etc. */

	FIX_TEXT_POKE0,

arch/arm/include/asm/highmem.h

+23 −10
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 
#ifndef _ASM_HIGHMEM_H

#define _ASM_HIGHMEM_H



#include <asm/kmap_types.h>

#include <asm/fixmap.h>



#define PKMAP_BASE		(PAGE_OFFSET - PMD_SIZE)

#define LAST_PKMAP		PTRS_PER_PTE
@@ -46,19 +46,32 @@ extern pte_t *pkmap_page_table; 


#ifdef ARCH_NEEDS_KMAP_HIGH_GET

extern void *kmap_high_get(struct page *page);

#else



static inline void *arch_kmap_local_high_get(struct page *page)

{

	if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !cache_is_vivt())

		return NULL;

	return kmap_high_get(page);

}

#define arch_kmap_local_high_get arch_kmap_local_high_get



#else /* ARCH_NEEDS_KMAP_HIGH_GET */

static inline void *kmap_high_get(struct page *page)

{

	return NULL;

}

#endif

#endif /* !ARCH_NEEDS_KMAP_HIGH_GET */



/*

 * The following functions are already defined by <linux/highmem.h>

 * when CONFIG_HIGHMEM is not set.

 */

#ifdef CONFIG_HIGHMEM

extern void *kmap_atomic_pfn(unsigned long pfn);

#endif

#define arch_kmap_local_post_map(vaddr, pteval)				\

	local_flush_tlb_kernel_page(vaddr)



#define arch_kmap_local_pre_unmap(vaddr)				\

do {									\

	if (cache_is_vivt())						\

		__cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);	\

} while (0)



#define arch_kmap_local_post_unmap(vaddr)				\

	local_flush_tlb_kernel_page(vaddr)



#endif

arch/arm/include/asm/kmap_types.h

deleted100644 → 0
+0 −10
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef __ARM_KMAP_TYPES_H

#define __ARM_KMAP_TYPES_H



/*

 * This is the "bare minimum".  AIO seems to require this.

 */

#define KM_TYPE_NR 16



#endif

arch/arm/mm/Makefile

+0 −1
Original line number Diff line number Diff line
@@ -19,7 +19,6 @@ obj-$(CONFIG_MODULES) += proc-syms.o 
obj-$(CONFIG_DEBUG_VIRTUAL)	+= physaddr.o



obj-$(CONFIG_ALIGNMENT_TRAP)	+= alignment.o

obj-$(CONFIG_HIGHMEM)		+= highmem.o

obj-$(CONFIG_HUGETLB_PAGE)	+= hugetlbpage.o

obj-$(CONFIG_ARM_PV_FIXUP)	+= pv-fixup-asm.o