1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2015 Synopsys, Inc. (www.synopsys.com) 4 */ 5 6 #ifndef _ASM_HIGHMEM_H 7 #define _ASM_HIGHMEM_H 8 9 #ifdef CONFIG_HIGHMEM 10 11 #include <uapi/asm/page.h> 12 #include <asm/kmap_types.h> 13 14 /* start after vmalloc area */ 15 #define FIXMAP_BASE (PAGE_OFFSET - FIXMAP_SIZE - PKMAP_SIZE) 16 #define FIXMAP_SIZE PGDIR_SIZE /* only 1 PGD worth */ 17 #define KM_TYPE_NR ((FIXMAP_SIZE >> PAGE_SHIFT)/NR_CPUS) 18 #define FIXMAP_ADDR(nr) (FIXMAP_BASE + ((nr) << PAGE_SHIFT)) 19 20 /* start after fixmap area */ 21 #define PKMAP_BASE (FIXMAP_BASE + FIXMAP_SIZE) 22 #define PKMAP_SIZE PGDIR_SIZE 23 #define LAST_PKMAP (PKMAP_SIZE >> PAGE_SHIFT) 24 #define LAST_PKMAP_MASK (LAST_PKMAP - 1) 25 #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) 26 #define PKMAP_NR(virt) (((virt) - PKMAP_BASE) >> PAGE_SHIFT) 27 28 #define kmap_prot PAGE_KERNEL 29 30 31 #include <asm/cacheflush.h> 32 33 extern void *kmap(struct page *page); 34 extern void *kmap_high(struct page *page); 35 extern void *kmap_atomic(struct page *page); 36 extern void __kunmap_atomic(void *kvaddr); 37 extern void kunmap_high(struct page *page); 38 39 extern void kmap_init(void); 40 41 static inline void flush_cache_kmaps(void) 42 { 43 flush_cache_all(); 44 } 45 46 static inline void kunmap(struct page *page) 47 { 48 BUG_ON(in_interrupt()); 49 if (!PageHighMem(page)) 50 return; 51 kunmap_high(page); 52 } 53 54 55 #endif 56 57 #endif 58