1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
|
// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/highmem.h>
#include <linux/kprobes.h>
/**
* flush_coherent_icache() - if a CPU has a coherent icache, flush it
* Return true if the cache was flushed, false otherwise
*/
static inline bool flush_coherent_icache(void)
{
/*
* For a snooping icache, we still need a dummy icbi to purge all the
* prefetched instructions from the ifetch buffers. We also need a sync
* before the icbi to order the the actual stores to memory that might
* have modified instructions with the icbi.
*/
if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {
mb(); /* sync */
icbi((void *)PAGE_OFFSET);
mb(); /* sync */
isync();
return true;
}
return false;
}
/**
* invalidate_icache_range() - Flush the icache by issuing icbi across an address range
* @start: the start address
* @stop: the stop address (exclusive)
*/
static void invalidate_icache_range(unsigned long start, unsigned long stop)
{
unsigned long shift = l1_icache_shift();
unsigned long bytes = l1_icache_bytes();
char *addr = (char *)(start & ~(bytes - 1));
unsigned long size = stop - (unsigned long)addr + (bytes - 1);
unsigned long i;
for (i = 0; i < size >> shift; i++, addr += bytes)
icbi(addr);
mb(); /* sync */
isync();
}
/**
* flush_icache_range: Write any modified data cache blocks out to memory
* and invalidate the corresponding blocks in the instruction cache
*
* Generic code will call this after writing memory, before executing from it.
*
* @start: the start address
* @stop: the stop address (exclusive)
*/
void flush_icache_range(unsigned long start, unsigned long stop)
{
if (flush_coherent_icache())
return;
clean_dcache_range(start, stop);
if (IS_ENABLED(CONFIG_44x)) {
/*
* Flash invalidate on 44x because we are passed kmapped
* addresses and this doesn't work for userspace pages due to
* the virtually tagged icache.
*/
iccci((void *)start);
mb(); /* sync */
isync();
} else
invalidate_icache_range(start, stop);
}
EXPORT_SYMBOL(flush_icache_range);
#ifdef CONFIG_HIGHMEM
/**
* flush_dcache_icache_phys() - Flush a page by it's physical address
* @physaddr: the physical address of the page
*/
static void flush_dcache_icache_phys(unsigned long physaddr)
{
unsigned long bytes = l1_dcache_bytes();
unsigned long nb = PAGE_SIZE / bytes;
unsigned long addr = physaddr & PAGE_MASK;
unsigned long msr, msr0;
unsigned long loop1 = addr, loop2 = addr;
msr0 = mfmsr();
msr = msr0 & ~MSR_DR;
/*
* This must remain as ASM to prevent potential memory accesses
* while the data MMU is disabled
*/
asm volatile(
" mtctr %2;\n"
" mtmsr %3;\n"
" isync;\n"
"0: dcbst 0, %0;\n"
" addi %0, %0, %4;\n"
" bdnz 0b;\n"
" sync;\n"
" mtctr %2;\n"
"1: icbi 0, %1;\n"
" addi %1, %1, %4;\n"
" bdnz 1b;\n"
" sync;\n"
" mtmsr %5;\n"
" isync;\n"
: "+&r" (loop1), "+&r" (loop2)
: "r" (nb), "r" (msr), "i" (bytes), "r" (msr0)
: "ctr", "memory");
}
NOKPROBE_SYMBOL(flush_dcache_icache_phys)
#else
static void flush_dcache_icache_phys(unsigned long physaddr)
{
}
#endif
/**
* __flush_dcache_icache(): Flush a particular page from the data cache to RAM.
* Note: this is necessary because the instruction cache does *not*
* snoop from the data cache.
*
* @p: the address of the page to flush
*/
static void __flush_dcache_icache(void *p)
{
unsigned long addr = (unsigned long)p & PAGE_MASK;
clean_dcache_range(addr, addr + PAGE_SIZE);
/*
* We don't flush the icache on 44x. Those have a virtual icache and we
* don't have access to the virtual address here (it's not the page
* vaddr but where it's mapped in user space). The flushing of the
* icache on these is handled elsewhere, when a change in the address
* space occurs, before returning to user space.
*/
if (mmu_has_feature(MMU_FTR_TYPE_44x))
return;
invalidate_icache_range(addr, addr + PAGE_SIZE);
}
static void flush_dcache_icache_hugepage(struct page *page)
{
int i;
int nr = compound_nr(page);
if (!PageHighMem(page)) {
for (i = 0; i < nr; i++)
__flush_dcache_icache(lowmem_page_address(page + i));
} else {
for (i = 0; i < nr; i++) {
void *start = kmap_local_page(page + i);
__flush_dcache_icache(start);
kunmap_local(start);
}
}
}
void flush_dcache_icache_page(struct page *page)
{
if (flush_coherent_icache())
return;
if (PageCompound(page))
return flush_dcache_icache_hugepage(page);
if (!PageHighMem(page)) {
__flush_dcache_icache(lowmem_page_address(page));
} else if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {
void *start = kmap_local_page(page);
__flush_dcache_icache(start);
kunmap_local(start);
} else {
flush_dcache_icache_phys(page_to_phys(page));
}
}
EXPORT_SYMBOL(flush_dcache_icache_page);
void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
{
clear_page(page);
/*
* We shouldn't have to do this, but some versions of glibc
* require it (ld.so assumes zero filled pages are icache clean)
* - Anton
*/
flush_dcache_page(pg);
}
EXPORT_SYMBOL(clear_user_page);
void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
struct page *pg)
{
copy_page(vto, vfrom);
/*
* We should be able to use the following optimisation, however
* there are two problems.
* Firstly a bug in some versions of binutils meant PLT sections
* were not marked executable.
* Secondly the first word in the GOT section is blrl, used
* to establish the GOT address. Until recently the GOT was
* not marked executable.
* - Anton
*/
#if 0
if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
return;
#endif
flush_dcache_page(pg);
}
void flush_icache_user_page(struct vm_area_struct *vma, struct page *page,
unsigned long addr, int len)
{
void *maddr;
maddr = kmap_local_page(page) + (addr & ~PAGE_MASK);
flush_icache_range((unsigned long)maddr, (unsigned long)maddr + len);
kunmap_local(maddr);
}
|
