Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: Russell King linux@armlinux.org.uk Cc: Arnd Bergmann arnd@arndb.de Cc: linux-arm-kernel@lists.infradead.org --- Note: Completely untested --- arch/arm/Kconfig | 1 arch/arm/include/asm/highmem.h | 30 +++++++--- arch/arm/mm/Makefile | 1 arch/arm/mm/highmem.c | 121 ----------------------------------------- 4 files changed, 23 insertions(+), 130 deletions(-)
--- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1499,6 +1499,7 @@ config HAVE_ARCH_PFN_VALID config HIGHMEM bool "High Memory Support" depends on MMU + select KMAP_ATOMIC_GENERIC help The address space of ARM processors is only 4 Gigabytes large and it has to accommodate user address space, kernel address --- a/arch/arm/include/asm/highmem.h +++ b/arch/arm/include/asm/highmem.h @@ -46,19 +46,33 @@ extern pte_t *pkmap_page_table;
#ifdef ARCH_NEEDS_KMAP_HIGH_GET extern void *kmap_high_get(struct page *page); + +#ifdef CONFIG_DEBUG_HIGHMEM +extern void *arch_kmap_temporary_high_get(struct page *page); #else +static inline void *arch_kmap_temporary_high_get(struct page *page) +{ + return kmap_high_get(page); +} +#endif /* !CONFIG_DEBUG_HIGHMEM */ + +#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_temp_post_map(vaddr, pteval) \ + local_flush_tlb_kernel_page(vaddr) + +#define arch_kmap_temp_pre_unmap(vaddr) \ +do { \ + if (cache_is_vivt()) \ + __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); \ +} while (0) + +#define arch_kmap_temp_post_unmap(vaddr) \ + local_flush_tlb_kernel_page(vaddr)
#endif --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -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
--- a/arch/arm/mm/highmem.c +++ /dev/null @@ -1,121 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * arch/arm/mm/highmem.c -- ARM highmem support - * - * Author: Nicolas Pitre - * Created: september 8, 2008 - * Copyright: Marvell Semiconductors Inc. - */ - -#include <linux/module.h> -#include <linux/highmem.h> -#include <linux/interrupt.h> -#include <asm/fixmap.h> -#include <asm/cacheflush.h> -#include <asm/tlbflush.h> -#include "mm.h" - -static inline void set_fixmap_pte(int idx, pte_t pte) -{ - unsigned long vaddr = __fix_to_virt(idx); - pte_t *ptep = virt_to_kpte(vaddr); - - set_pte_ext(ptep, pte, 0); - local_flush_tlb_kernel_page(vaddr); -} - -static inline pte_t get_fixmap_pte(unsigned long vaddr) -{ - pte_t *ptep = virt_to_kpte(vaddr); - - return *ptep; -} - -void *kmap_atomic_high_prot(struct page *page, pgprot_t prot) -{ - unsigned int idx; - unsigned long vaddr; - void *kmap; - int type; - -#ifdef CONFIG_DEBUG_HIGHMEM - /* - * There is no cache coherency issue when non VIVT, so force the - * dedicated kmap usage for better debugging purposes in that case. - */ - if (!cache_is_vivt()) - kmap = NULL; - else -#endif - kmap = kmap_high_get(page); - if (kmap) - return kmap; - - type = kmap_atomic_idx_push(); - - idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); - vaddr = __fix_to_virt(idx); -#ifdef CONFIG_DEBUG_HIGHMEM - /* - * With debugging enabled, kunmap_atomic forces that entry to 0. - * Make sure it was indeed properly unmapped. - */ - BUG_ON(!pte_none(get_fixmap_pte(vaddr))); -#endif - /* - * When debugging is off, kunmap_atomic leaves the previous mapping - * in place, so the contained TLB flush ensures the TLB is updated - * with the new mapping. - */ - set_fixmap_pte(idx, mk_pte(page, prot)); - - return (void *)vaddr; -} -EXPORT_SYMBOL(kmap_atomic_high_prot); - -void kunmap_atomic_high(void *kvaddr) -{ - unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; - int idx, type; - - if (kvaddr >= (void *)FIXADDR_START) { - type = kmap_atomic_idx(); - idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); - - if (cache_is_vivt()) - __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); -#ifdef CONFIG_DEBUG_HIGHMEM - BUG_ON(vaddr != __fix_to_virt(idx)); - set_fixmap_pte(idx, __pte(0)); -#else - (void) idx; /* to kill a warning */ -#endif - kmap_atomic_idx_pop(); - } else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) { - /* this address was obtained through kmap_high_get() */ - kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)])); - } -} -EXPORT_SYMBOL(kunmap_atomic_high); - -void *kmap_atomic_pfn(unsigned long pfn) -{ - unsigned long vaddr; - int idx, type; - struct page *page = pfn_to_page(pfn); - - preempt_disable(); - pagefault_disable(); - if (!PageHighMem(page)) - return page_address(page); - - type = kmap_atomic_idx_push(); - idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); - vaddr = __fix_to_virt(idx); -#ifdef CONFIG_DEBUG_HIGHMEM - BUG_ON(!pte_none(get_fixmap_pte(vaddr))); -#endif - set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot)); - - return (void *)vaddr; -}