diff options
Diffstat (limited to 'arch/arc')
| -rw-r--r-- | arch/arc/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arc/include/asm/highmem.h | 26 | ||||
| -rw-r--r-- | arch/arc/include/asm/kmap_types.h | 14 | ||||
| -rw-r--r-- | arch/arc/mm/highmem.c | 54 |
4 files changed, 26 insertions, 69 deletions
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 0a89cc9def65..d8804001d550 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -507,6 +507,7 @@ config LINUX_RAM_BASE config HIGHMEM bool "High Memory Support" select ARCH_DISCONTIGMEM_ENABLE + select KMAP_LOCAL help With ARC 2G:2G address split, only upper 2G is directly addressable by kernel. Enable this to potentially allow access to rest of 2G and PAE diff --git a/arch/arc/include/asm/highmem.h b/arch/arc/include/asm/highmem.h index 6e5eafb3afdd..a6b8e2c352c4 100644 --- a/arch/arc/include/asm/highmem.h +++ b/arch/arc/include/asm/highmem.h @@ -9,17 +9,29 @@ #ifdef CONFIG_HIGHMEM #include <uapi/asm/page.h> -#include <asm/kmap_types.h> +#include <asm/kmap_size.h> + +#define FIXMAP_SIZE PGDIR_SIZE +#define PKMAP_SIZE PGDIR_SIZE /* start after vmalloc area */ #define FIXMAP_BASE (PAGE_OFFSET - FIXMAP_SIZE - PKMAP_SIZE) -#define FIXMAP_SIZE PGDIR_SIZE /* only 1 PGD worth */ -#define KM_TYPE_NR ((FIXMAP_SIZE >> PAGE_SHIFT)/NR_CPUS) -#define FIXMAP_ADDR(nr) (FIXMAP_BASE + ((nr) << PAGE_SHIFT)) + +#define FIX_KMAP_SLOTS (KM_MAX_IDX * NR_CPUS) +#define FIX_KMAP_BEGIN (0UL) +#define FIX_KMAP_END ((FIX_KMAP_BEGIN + FIX_KMAP_SLOTS) - 1) + +#define FIXADDR_TOP (FIXMAP_BASE + (FIX_KMAP_END << PAGE_SHIFT)) + +/* + * This should be converted to the asm-generic version, but of course this + * is needlessly different from all other architectures. Sigh - tglx + */ +#define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT)) +#define __virt_to_fix(x) (((FIXADDR_TOP - ((x) & PAGE_MASK))) >> PAGE_SHIFT) /* start after fixmap area */ #define PKMAP_BASE (FIXMAP_BASE + FIXMAP_SIZE) -#define PKMAP_SIZE PGDIR_SIZE #define LAST_PKMAP (PKMAP_SIZE >> PAGE_SHIFT) #define LAST_PKMAP_MASK (LAST_PKMAP - 1) #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) @@ -29,11 +41,13 @@ extern void kmap_init(void); +#define arch_kmap_local_post_unmap(vaddr) \ + local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE) + static inline void flush_cache_kmaps(void) { flush_cache_all(); } - #endif #endif diff --git a/arch/arc/include/asm/kmap_types.h b/arch/arc/include/asm/kmap_types.h deleted file mode 100644 index fecf7851ec32..000000000000 --- a/arch/arc/include/asm/kmap_types.h +++ /dev/null @@ -1,14 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-only */ -/* - * Copyright (C) 2015 Synopsys, Inc. (www.synopsys.com) - */ - -#ifndef _ASM_KMAP_TYPES_H -#define _ASM_KMAP_TYPES_H - -/* - * We primarily need to define KM_TYPE_NR here but that in turn - * is a function of PGDIR_SIZE etc. - * To avoid circular deps issue, put everything in asm/highmem.h - */ -#endif diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c index 1b9f473c6369..c79912a6b196 100644 --- a/arch/arc/mm/highmem.c +++ b/arch/arc/mm/highmem.c @@ -36,9 +36,8 @@ * This means each only has 1 PGDIR_SIZE worth of kvaddr mappings, which means * 2M of kvaddr space for typical config (8K page and 11:8:13 traversal split) * - * - fixmap anyhow needs a limited number of mappings. So 2M kvaddr == 256 PTE - * slots across NR_CPUS would be more than sufficient (generic code defines - * KM_TYPE_NR as 20). + * - The fixed KMAP slots for kmap_local/atomic() require KM_MAX_IDX slots per + * CPU. So the number of CPUs sharing a single PTE page is limited. * * - pkmap being preemptible, in theory could do with more than 256 concurrent * mappings. However, generic pkmap code: map_new_virtual(), doesn't traverse @@ -47,48 +46,6 @@ */ extern pte_t * pkmap_page_table; -static pte_t * fixmap_page_table; - -void *kmap_atomic_high_prot(struct page *page, pgprot_t prot) -{ - int idx, cpu_idx; - unsigned long vaddr; - - cpu_idx = kmap_atomic_idx_push(); - idx = cpu_idx + KM_TYPE_NR * smp_processor_id(); - vaddr = FIXMAP_ADDR(idx); - - set_pte_at(&init_mm, vaddr, fixmap_page_table + idx, - mk_pte(page, prot)); - - return (void *)vaddr; -} -EXPORT_SYMBOL(kmap_atomic_high_prot); - -void kunmap_atomic_high(void *kv) -{ - unsigned long kvaddr = (unsigned long)kv; - - if (kvaddr >= FIXMAP_BASE && kvaddr < (FIXMAP_BASE + FIXMAP_SIZE)) { - - /* - * Because preemption is disabled, this vaddr can be associated - * with the current allocated index. - * But in case of multiple live kmap_atomic(), it still relies on - * callers to unmap in right order. - */ - int cpu_idx = kmap_atomic_idx(); - int idx = cpu_idx + KM_TYPE_NR * smp_processor_id(); - - WARN_ON(kvaddr != FIXMAP_ADDR(idx)); - - pte_clear(&init_mm, kvaddr, fixmap_page_table + idx); - local_flush_tlb_kernel_range(kvaddr, kvaddr + PAGE_SIZE); - - kmap_atomic_idx_pop(); - } -} -EXPORT_SYMBOL(kunmap_atomic_high); static noinline pte_t * __init alloc_kmap_pgtable(unsigned long kvaddr) { @@ -108,10 +65,9 @@ void __init kmap_init(void) { /* Due to recursive include hell, we can't do this in processor.h */ BUILD_BUG_ON(PAGE_OFFSET < (VMALLOC_END + FIXMAP_SIZE + PKMAP_SIZE)); + BUILD_BUG_ON(LAST_PKMAP > PTRS_PER_PTE); + BUILD_BUG_ON(FIX_KMAP_SLOTS > PTRS_PER_PTE); - BUILD_BUG_ON(KM_TYPE_NR > PTRS_PER_PTE); pkmap_page_table = alloc_kmap_pgtable(PKMAP_BASE); - - BUILD_BUG_ON(LAST_PKMAP > PTRS_PER_PTE); - fixmap_page_table = alloc_kmap_pgtable(FIXMAP_BASE); + alloc_kmap_pgtable(FIXMAP_BASE); } |