1 /* 2 * include/asm-xtensa/highmem.h 3 * 4 * This file is subject to the terms and conditions of the GNU General 5 * Public License. See the file "COPYING" in the main directory of 6 * this archive for more details. 7 * 8 * Copyright (C) 2003 - 2005 Tensilica Inc. 9 * Copyright (C) 2014 Cadence Design Systems Inc. 10 */ 11 12 #ifndef _XTENSA_HIGHMEM_H 13 #define _XTENSA_HIGHMEM_H 14 15 #include <linux/wait.h> 16 #include <asm/cacheflush.h> 17 #include <asm/fixmap.h> 18 #include <asm/kmap_types.h> 19 #include <asm/pgtable.h> 20 21 #define PKMAP_BASE ((FIXADDR_START - \ 22 (LAST_PKMAP + 1) * PAGE_SIZE) & PMD_MASK) 23 #define LAST_PKMAP (PTRS_PER_PTE * DCACHE_N_COLORS) 24 #define LAST_PKMAP_MASK (LAST_PKMAP - 1) 25 #define PKMAP_NR(virt) (((virt) - PKMAP_BASE) >> PAGE_SHIFT) 26 #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) 27 28 #define kmap_prot PAGE_KERNEL_EXEC 29 30 #if DCACHE_WAY_SIZE > PAGE_SIZE 31 #define get_pkmap_color get_pkmap_color 32 static inline int get_pkmap_color(struct page *page) 33 { 34 return DCACHE_ALIAS(page_to_phys(page)); 35 } 36 37 extern unsigned int last_pkmap_nr_arr[]; 38 39 static inline unsigned int get_next_pkmap_nr(unsigned int color) 40 { 41 last_pkmap_nr_arr[color] = 42 (last_pkmap_nr_arr[color] + DCACHE_N_COLORS) & LAST_PKMAP_MASK; 43 return last_pkmap_nr_arr[color] + color; 44 } 45 46 static inline int no_more_pkmaps(unsigned int pkmap_nr, unsigned int color) 47 { 48 return pkmap_nr < DCACHE_N_COLORS; 49 } 50 51 static inline int get_pkmap_entries_count(unsigned int color) 52 { 53 return LAST_PKMAP / DCACHE_N_COLORS; 54 } 55 56 extern wait_queue_head_t pkmap_map_wait_arr[]; 57 58 static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color) 59 { 60 return pkmap_map_wait_arr + color; 61 } 62 #endif 63 64 extern pte_t *pkmap_page_table; 65 66 void *kmap_high(struct page *page); 67 void kunmap_high(struct page *page); 68 69 static inline void *kmap(struct page *page) 70 { 71 /* Check if this memory layout is broken because PKMAP overlaps 72 * page table. 73 */ 74 BUILD_BUG_ON(PKMAP_BASE < 75 TLBTEMP_BASE_1 + TLBTEMP_SIZE); 76 BUG_ON(in_interrupt()); 77 if (!PageHighMem(page)) 78 return page_address(page); 79 return kmap_high(page); 80 } 81 82 static inline void kunmap(struct page *page) 83 { 84 BUG_ON(in_interrupt()); 85 if (!PageHighMem(page)) 86 return; 87 kunmap_high(page); 88 } 89 90 static inline void flush_cache_kmaps(void) 91 { 92 flush_cache_all(); 93 } 94 95 void *kmap_atomic(struct page *page); 96 void __kunmap_atomic(void *kvaddr); 97 98 void kmap_init(void); 99 100 #endif 101