blob: 49a32b4fe5172bea0a6427af42ca4b290b2ed1da (
plain)
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
|
/*
* Variable page size handling -- target specific part.
*
* Copyright (c) 2003 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#define IN_PAGE_VARY 1
#include "qemu/osdep.h"
#include "exec/page-vary.h"
#include "exec/target_page.h"
/*
* For system mode, the minimum comes from the number of bits
* required for maximum alignment (6) and the number of bits
* required for TLB_FLAGS_MASK (3).
*
* For user mode, TARGET_PAGE_BITS_VARY is a hack to allow the target
* page size to match the host page size. Mostly, this reduces the
* ordinary target page size to run on a host with 4KiB pages (i.e. x86).
* There is no true minimum required by the implementation, but keep the
* same minimum as for system mode for sanity.
* See linux-user/mmap.c, mmap_h_lt_g and mmap_h_gt_g.
*/
#define TARGET_PAGE_BITS_MIN 9
#ifndef TARGET_PAGE_BITS_VARY
QEMU_BUILD_BUG_ON(TARGET_PAGE_BITS < TARGET_PAGE_BITS_MIN);
#endif
#ifndef CONFIG_USER_ONLY
#include "exec/tlb-flags.h"
QEMU_BUILD_BUG_ON(TLB_FLAGS_MASK & ((1u < TARGET_PAGE_BITS_MIN) - 1));
int migration_legacy_page_bits(void)
{
#ifdef TARGET_PAGE_BITS_VARY
QEMU_BUILD_BUG_ON(TARGET_PAGE_BITS_LEGACY < TARGET_PAGE_BITS_MIN);
return TARGET_PAGE_BITS_LEGACY;
#else
return TARGET_PAGE_BITS;
#endif
}
#endif
bool set_preferred_target_page_bits(int bits)
{
assert(bits >= TARGET_PAGE_BITS_MIN);
#ifdef TARGET_PAGE_BITS_VARY
return set_preferred_target_page_bits_common(bits);
#else
return true;
#endif
}
void finalize_target_page_bits(void)
{
#ifndef TARGET_PAGE_BITS_VARY
finalize_target_page_bits_common(TARGET_PAGE_BITS);
#elif defined(CONFIG_USER_ONLY)
assert(target_page.bits != 0);
finalize_target_page_bits_common(target_page.bits);
#else
finalize_target_page_bits_common(TARGET_PAGE_BITS_LEGACY);
#endif
}
|
