1/*
2 * Based on arch/arm/mm/flush.c
3 *
4 * Copyright (C) 1995-2002 Russell King
5 * Copyright (C) 2012 ARM Ltd.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18 */
19
20#include <linux/export.h>
21#include <linux/mm.h>
22#include <linux/pagemap.h>
23
24#include <asm/cacheflush.h>
25#include <asm/cachetype.h>
26#include <asm/tlbflush.h>
27
28#include "mm.h"
29
30void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
31		       unsigned long end)
32{
33	if (vma->vm_flags & VM_EXEC)
34		__flush_icache_all();
35}
36
37static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
38				unsigned long uaddr, void *kaddr,
39				unsigned long len)
40{
41	if (vma->vm_flags & VM_EXEC) {
42		unsigned long addr = (unsigned long)kaddr;
43		if (icache_is_aliasing()) {
44			__flush_dcache_area(kaddr, len);
45			__flush_icache_all();
46		} else {
47			flush_icache_range(addr, addr + len);
48		}
49	}
50}
51
52/*
53 * Copy user data from/to a page which is mapped into a different processes
54 * address space.  Really, we want to allow our "user space" model to handle
55 * this.
56 *
57 * Note that this code needs to run on the current CPU.
58 */
59void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
60		       unsigned long uaddr, void *dst, const void *src,
61		       unsigned long len)
62{
63#ifdef CONFIG_SMP
64	preempt_disable();
65#endif
66	memcpy(dst, src, len);
67	flush_ptrace_access(vma, page, uaddr, dst, len);
68#ifdef CONFIG_SMP
69	preempt_enable();
70#endif
71}
72
73void __sync_icache_dcache(pte_t pte, unsigned long addr)
74{
75	struct page *page = pte_page(pte);
76
77	/* no flushing needed for anonymous pages */
78	if (!page_mapping(page))
79		return;
80
81	if (!test_and_set_bit(PG_dcache_clean, &page->flags)) {
82		__flush_dcache_area(page_address(page),
83				PAGE_SIZE << compound_order(page));
84		__flush_icache_all();
85	} else if (icache_is_aivivt()) {
86		__flush_icache_all();
87	}
88}
89
90/*
91 * This function is called when a page has been modified by the kernel. Mark
92 * it as dirty for later flushing when mapped in user space (if executable,
93 * see __sync_icache_dcache).
94 */
95void flush_dcache_page(struct page *page)
96{
97	if (test_bit(PG_dcache_clean, &page->flags))
98		clear_bit(PG_dcache_clean, &page->flags);
99}
100EXPORT_SYMBOL(flush_dcache_page);
101
102/*
103 * Additional functions defined in assembly.
104 */
105EXPORT_SYMBOL(flush_cache_all);
106EXPORT_SYMBOL(flush_icache_range);
107
108#ifdef CONFIG_TRANSPARENT_HUGEPAGE
109#ifdef CONFIG_HAVE_RCU_TABLE_FREE
110void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
111			  pmd_t *pmdp)
112{
113	pmd_t pmd = pmd_mksplitting(*pmdp);
114
115	VM_BUG_ON(address & ~PMD_MASK);
116	set_pmd_at(vma->vm_mm, address, pmdp, pmd);
117
118	/* dummy IPI to serialise against fast_gup */
119	kick_all_cpus_sync();
120}
121#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
122#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
123