1/*
  2 * Copyright (C) 2004-2006 Atmel Corporation
  3 *
  4 * This program is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License version 2 as
  6 * published by the Free Software Foundation.
  7 */
  8
  9#include <linux/highmem.h>
 10#include <linux/unistd.h>
 11
 12#include <asm/cacheflush.h>
 13#include <asm/cachectl.h>
 14#include <asm/processor.h>
 15#include <asm/uaccess.h>
 16#include <asm/syscalls.h>
 17
 18/*
 19 * If you attempt to flush anything more than this, you need superuser
 20 * privileges.  The value is completely arbitrary.
 21 */
 22#define CACHEFLUSH_MAX_LEN	1024
 23
 24void invalidate_dcache_region(void *start, size_t size)
 25{
 26	unsigned long v, begin, end, linesz, mask;
 27
 28	linesz = boot_cpu_data.dcache.linesz;
 29	mask = linesz - 1;
 30
 31	/* when first and/or last cachelines are shared, flush them
 32	 * instead of invalidating ... never discard valid data!
 33	 */
 34	begin = (unsigned long)start;
 35	end = begin + size;
 36
 37	if (begin & mask) {
 38		flush_dcache_line(start);
 39		begin += linesz;
 40	}
 41	if (end & mask) {
 42		flush_dcache_line((void *)end);
 43		end &= ~mask;
 44	}
 45
 46	/* remaining cachelines only need invalidation */
 47	for (v = begin; v < end; v += linesz)
 48		invalidate_dcache_line((void *)v);
 49	flush_write_buffer();
 50}
 51
 52void clean_dcache_region(void *start, size_t size)
 53{
 54	unsigned long v, begin, end, linesz;
 55
 56	linesz = boot_cpu_data.dcache.linesz;
 57	begin = (unsigned long)start & ~(linesz - 1);
 58	end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);
 59
 60	for (v = begin; v < end; v += linesz)
 61		clean_dcache_line((void *)v);
 62	flush_write_buffer();
 63}
 64
 65void flush_dcache_region(void *start, size_t size)
 66{
 67	unsigned long v, begin, end, linesz;
 68
 69	linesz = boot_cpu_data.dcache.linesz;
 70	begin = (unsigned long)start & ~(linesz - 1);
 71	end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);
 72
 73	for (v = begin; v < end; v += linesz)
 74		flush_dcache_line((void *)v);
 75	flush_write_buffer();
 76}
 77
 78void invalidate_icache_region(void *start, size_t size)
 79{
 80	unsigned long v, begin, end, linesz;
 81
 82	linesz = boot_cpu_data.icache.linesz;
 83	begin = (unsigned long)start & ~(linesz - 1);
 84	end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);
 85
 86	for (v = begin; v < end; v += linesz)
 87		invalidate_icache_line((void *)v);
 88}
 89
 90static inline void __flush_icache_range(unsigned long start, unsigned long end)
 91{
 92	unsigned long v, linesz;
 93
 94	linesz = boot_cpu_data.dcache.linesz;
 95	for (v = start; v < end; v += linesz) {
 96		clean_dcache_line((void *)v);
 97		invalidate_icache_line((void *)v);
 98	}
 99
100	flush_write_buffer();
101}
102
103/*
104 * This one is called after a module has been loaded.
105 */
106void flush_icache_range(unsigned long start, unsigned long end)
107{
108	unsigned long linesz;
109
110	linesz = boot_cpu_data.dcache.linesz;
111	__flush_icache_range(start & ~(linesz - 1),
112			     (end + linesz - 1) & ~(linesz - 1));
113}
114
115/*
116 * This one is called from __do_fault() and do_swap_page().
117 */
118void flush_icache_page(struct vm_area_struct *vma, struct page *page)
119{
120	if (vma->vm_flags & VM_EXEC) {
121		void *v = page_address(page);
122		__flush_icache_range((unsigned long)v, (unsigned long)v + PAGE_SIZE);
123	}
124}
125
126asmlinkage int sys_cacheflush(int operation, void __user *addr, size_t len)
127{
128	int ret;
129
130	if (len > CACHEFLUSH_MAX_LEN) {
131		ret = -EPERM;
132		if (!capable(CAP_SYS_ADMIN))
133			goto out;
134	}
135
136	ret = -EFAULT;
137	if (!access_ok(VERIFY_WRITE, addr, len))
138		goto out;
139
140	switch (operation) {
141	case CACHE_IFLUSH:
142		flush_icache_range((unsigned long)addr,
143				   (unsigned long)addr + len);
144		ret = 0;
145		break;
146	default:
147		ret = -EINVAL;
148	}
149
150out:
151	return ret;
152}
153
154void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
155		unsigned long vaddr, void *dst, const void *src,
156		unsigned long len)
157{
158	memcpy(dst, src, len);
159	if (vma->vm_flags & VM_EXEC)
160		flush_icache_range((unsigned long)dst,
161				(unsigned long)dst + len);
162}