From 5f037ea3b26767e0b1bdc522948321b282268b49 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 3 Nov 2020 10:27:26 +0100 Subject: [PATCH] nds32/mm/highmem: Switch to generic kmap atomic The mapping code is odd and looks broken. See FIXME in the comment. Also fix the harmless off by one in the FIX_KMAP_END define. Signed-off-by: Thomas Gleixner Cc: Nick Hu Cc: Greentime Hu Cc: Vincent Chen Cc: Arnd Bergmann Link: https://lore.kernel.org/r/20201103095857.980576055@linutronix.de --- arch/nds32/Kconfig.cpu | 1 + arch/nds32/include/asm/fixmap.h | 4 +-- arch/nds32/include/asm/highmem.h | 22 +++++++++++---- arch/nds32/mm/Makefile | 1 - arch/nds32/mm/highmem.c | 48 -------------------------------- 5 files changed, 19 insertions(+), 57 deletions(-) delete mode 100644 arch/nds32/mm/highmem.c diff --git a/arch/nds32/Kconfig.cpu b/arch/nds32/Kconfig.cpu index f88a12fdf0f3..c10759952485 100644 --- a/arch/nds32/Kconfig.cpu +++ b/arch/nds32/Kconfig.cpu @@ -157,6 +157,7 @@ config HW_SUPPORT_UNALIGNMENT_ACCESS config HIGHMEM bool "High Memory Support" depends on MMU && !CPU_CACHE_ALIASING + select KMAP_LOCAL help The address space of Andes processors is only 4 Gigabytes large and it has to accommodate user address space, kernel address diff --git a/arch/nds32/include/asm/fixmap.h b/arch/nds32/include/asm/fixmap.h index 5a4bf11e5800..2fa09a2de428 100644 --- a/arch/nds32/include/asm/fixmap.h +++ b/arch/nds32/include/asm/fixmap.h @@ -6,7 +6,7 @@ #ifdef CONFIG_HIGHMEM #include -#include +#include #endif enum fixed_addresses { @@ -14,7 +14,7 @@ enum fixed_addresses { FIX_KMAP_RESERVED, FIX_KMAP_BEGIN, #ifdef CONFIG_HIGHMEM - FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS), + FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1, #endif FIX_EARLYCON_MEM_BASE, __end_of_fixed_addresses diff --git a/arch/nds32/include/asm/highmem.h b/arch/nds32/include/asm/highmem.h index fe986d0e6e3f..16159a8716f2 100644 --- a/arch/nds32/include/asm/highmem.h +++ b/arch/nds32/include/asm/highmem.h @@ -5,7 +5,6 @@ #define _ASM_HIGHMEM_H #include -#include #include /* @@ -45,11 +44,22 @@ extern pte_t *pkmap_page_table; extern void kmap_init(void); /* - * The following functions are already defined by - * when CONFIG_HIGHMEM is not set. + * FIXME: The below looks broken vs. a kmap_atomic() in task context which + * is interupted and another kmap_atomic() happens in interrupt context. + * But what do I know about nds32. -- tglx */ -#ifdef CONFIG_HIGHMEM -extern void *kmap_atomic_pfn(unsigned long pfn); -#endif +#define arch_kmap_local_post_map(vaddr, pteval) \ + do { \ + __nds32__tlbop_inv(vaddr); \ + __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN); \ + __nds32__tlbop_rwr(pteval); \ + __nds32__isb(); \ + } while (0) + +#define arch_kmap_local_pre_unmap(vaddr) \ + do { \ + __nds32__tlbop_inv(vaddr); \ + __nds32__isb(); \ + } while (0) #endif diff --git a/arch/nds32/mm/Makefile b/arch/nds32/mm/Makefile index 897ecaf5cf54..14fb2e8eb036 100644 --- a/arch/nds32/mm/Makefile +++ b/arch/nds32/mm/Makefile @@ -3,7 +3,6 @@ obj-y := extable.o tlb.o fault.o init.o mmap.o \ mm-nds32.o cacheflush.o proc.o obj-$(CONFIG_ALIGNMENT_TRAP) += alignment.o -obj-$(CONFIG_HIGHMEM) += highmem.o ifdef CONFIG_FUNCTION_TRACER CFLAGS_REMOVE_proc.o = $(CC_FLAGS_FTRACE) diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c deleted file mode 100644 index 4284cd59e21a..000000000000 --- a/arch/nds32/mm/highmem.c +++ /dev/null @@ -1,48 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -// Copyright (C) 2005-2017 Andes Technology Corporation - -#include -#include -#include -#include -#include -#include -#include -#include - -void *kmap_atomic_high_prot(struct page *page, pgprot_t prot) -{ - unsigned int idx; - unsigned long vaddr, pte; - int type; - pte_t *ptep; - - type = kmap_atomic_idx_push(); - - idx = type + KM_TYPE_NR * smp_processor_id(); - vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); - pte = (page_to_pfn(page) << PAGE_SHIFT) | prot; - ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr); - set_pte(ptep, pte); - - __nds32__tlbop_inv(vaddr); - __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN); - __nds32__tlbop_rwr(pte); - __nds32__isb(); - return (void *)vaddr; -} -EXPORT_SYMBOL(kmap_atomic_high_prot); - -void kunmap_atomic_high(void *kvaddr) -{ - if (kvaddr >= (void *)FIXADDR_START) { - unsigned long vaddr = (unsigned long)kvaddr; - pte_t *ptep; - kmap_atomic_idx_pop(); - __nds32__tlbop_inv(vaddr); - __nds32__isb(); - ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr); - set_pte(ptep, 0); - } -} -EXPORT_SYMBOL(kunmap_atomic_high);