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
|
/* SPDX-License-Identifier: BSD-4-Clause-UC */
#ifndef _VM_H
#define _VM_H
#include <string.h>
#include <stdint.h>
#include <arch/encoding.h>
#define EXTRACT_FIELD(val, which) (((val) & (which)) / ((which) & ~((which)-1)))
#define INSERT_FIELD(val, which, fieldval) (((val) & ~(which)) | ((fieldval) * ((which) & ~((which)-1))))
void mstatus_init(void); // need to setup mstatus so we know we have virtual memory
#define DEFINE_MPRV_READ_FLAGS(name, type, insn, flags) \
static inline type name(type *p); \
static inline type name(type *p) \
{ \
size_t mprv = flags; \
type value; \
asm ( \
"csrs mstatus, %1\n" \
STRINGIFY(insn) " %0, 0(%2)\n" \
"csrc mstatus, %1\n" \
: "=&r"(value) : "r"(mprv), "r"(p) : "memory" \
); \
return value; \
}
#define DEFINE_MPRV_READ(name, type, insn) \
DEFINE_MPRV_READ_FLAGS(name, type, insn, MSTATUS_MPRV)
#define DEFINE_MPRV_READ_MXR(name, type, insn) \
DEFINE_MPRV_READ_FLAGS(name, type, insn, MSTATUS_MPRV | MSTATUS_MXR)
#define DEFINE_MPRV_WRITE(name, type, insn) \
static inline void name(type *p, type value); \
static inline void name(type *p, type value) \
{ \
size_t mprv = MSTATUS_MPRV; \
asm ( \
"csrs mstatus, %0\n" \
STRINGIFY(insn) " %1, 0(%2)\n" \
"csrc mstatus, %0\n" \
:: "r"(mprv), "r"(value), "r"(p) : "memory" \
); \
}
/*
* mprv_{read,write}_* - Modified privilege memory access functions.
*
* These inline functions perform a read or write memory operation with the
* mstatus.MPRV bit set. This causes the memory protections and translation of
* the previous mode (e.g. U-mode, if we're handling a trap from U-mode) to be
* applied.
*
* The user of these functions must make sure to avoid trap loops through
* unaligned memory accesses.
*/
DEFINE_MPRV_READ(mprv_read_u8, uint8_t, lbu)
DEFINE_MPRV_READ(mprv_read_u16, uint16_t, lhu)
DEFINE_MPRV_READ(mprv_read_u32, uint32_t, lwu)
DEFINE_MPRV_READ(mprv_read_u64, uint64_t, ld)
DEFINE_MPRV_READ(mprv_read_long, long, ld)
DEFINE_MPRV_READ(mprv_read_ulong, unsigned long, ld)
DEFINE_MPRV_READ_MXR(mprv_read_mxr_u8, uint8_t, lbu)
DEFINE_MPRV_READ_MXR(mprv_read_mxr_u16, uint16_t, lhu)
DEFINE_MPRV_READ_MXR(mprv_read_mxr_u32, uint32_t, lwu)
DEFINE_MPRV_READ_MXR(mprv_read_mxr_u64, uint64_t, ld)
DEFINE_MPRV_READ_MXR(mprv_read_mxr_long, long, ld)
DEFINE_MPRV_READ_MXR(mprv_read_mxr_ulong, unsigned long, ld)
DEFINE_MPRV_WRITE(mprv_write_u8, uint8_t, sb)
DEFINE_MPRV_WRITE(mprv_write_u16, uint16_t, sh)
DEFINE_MPRV_WRITE(mprv_write_u32, uint32_t, sw)
DEFINE_MPRV_WRITE(mprv_write_u64, uint64_t, sd)
DEFINE_MPRV_WRITE(mprv_write_long, long, sd)
DEFINE_MPRV_WRITE(mprv_write_ulong, unsigned long, sd)
#if __riscv_xlen == 32
DEFINE_MPRV_READ(mprv_read_uintptr_t, uintptr_t, lw)
DEFINE_MPRV_READ(mprv_write_uintptr_t, uintptr_t, sw)
#elif __riscv_xlen == 64
DEFINE_MPRV_READ(mprv_read_uintptr_t, uintptr_t, ld)
DEFINE_MPRV_READ(mprv_write_uintptr_t, uintptr_t, sd)
#endif
#undef DEFINE_MPRV_READ_FLAGS
#undef DEFINE_MPRV_READ
#undef DEFINE_MPRV_READ_MXR
#undef DEFINE_MPRV_WRITE
#endif
|