1 /* SPDX-License-Identifier: BSD-4-Clause-UC */ 2 3 #ifndef _VM_H 4 #define _VM_H 5 6 #include <stdint.h> 7 #include <arch/encoding.h> 8 9 #define EXTRACT_FIELD(val, which) (((val) & (which)) / ((which) & ~((which)-1))) 10 #define INSERT_FIELD(val, which, fieldval) (((val) & ~(which)) | ((fieldval) * ((which) & ~((which)-1)))) 11 12 void mstatus_init(void); // need to setup mstatus so we know we have virtual memory 13 14 #define DEFINE_MPRV_READ_FLAGS(name, type, insn, flags) \ 15 static inline type name(type *p); \ 16 static inline type name(type *p) \ 17 { \ 18 size_t mprv = flags; \ 19 type value; \ 20 asm ( \ 21 "csrs mstatus, %1\n" \ 22 STRINGIFY(insn) " %0, 0(%2)\n" \ 23 "csrc mstatus, %1\n" \ 24 : "=&r"(value) : "r"(mprv), "r"(p) : "memory" \ 25 ); \ 26 return value; \ 27 } 28 29 #define DEFINE_MPRV_READ(name, type, insn) \ 30 DEFINE_MPRV_READ_FLAGS(name, type, insn, MSTATUS_MPRV) 31 32 #define DEFINE_MPRV_READ_MXR(name, type, insn) \ 33 DEFINE_MPRV_READ_FLAGS(name, type, insn, MSTATUS_MPRV | MSTATUS_MXR) 34 35 #define DEFINE_MPRV_WRITE(name, type, insn) \ 36 static inline void name(type *p, type value); \ 37 static inline void name(type *p, type value) \ 38 { \ 39 size_t mprv = MSTATUS_MPRV; \ 40 asm ( \ 41 "csrs mstatus, %0\n" \ 42 STRINGIFY(insn) " %1, 0(%2)\n" \ 43 "csrc mstatus, %0\n" \ 44 :: "r"(mprv), "r"(value), "r"(p) : "memory" \ 45 ); \ 46 } 47 48 /* 49 * mprv_{read,write}_* - Modified privilege memory access functions. 50 * 51 * These inline functions perform a read or write memory operation with the 52 * mstatus.MPRV bit set. This causes the memory protections and translation of 53 * the previous mode (e.g. U-mode, if we're handling a trap from U-mode) to be 54 * applied. 55 * 56 * The user of these functions must make sure to avoid trap loops through 57 * unaligned memory accesses. 58 */ 59 DEFINE_MPRV_READ(mprv_read_u8, uint8_t, lbu) 60 DEFINE_MPRV_READ(mprv_read_u16, uint16_t, lhu) 61 DEFINE_MPRV_READ(mprv_read_u32, uint32_t, lwu) 62 DEFINE_MPRV_READ(mprv_read_u64, uint64_t, ld) 63 DEFINE_MPRV_READ(mprv_read_long, long, ld) 64 DEFINE_MPRV_READ(mprv_read_ulong, unsigned long, ld) 65 DEFINE_MPRV_READ_MXR(mprv_read_mxr_u8, uint8_t, lbu) 66 DEFINE_MPRV_READ_MXR(mprv_read_mxr_u16, uint16_t, lhu) 67 DEFINE_MPRV_READ_MXR(mprv_read_mxr_u32, uint32_t, lwu) 68 DEFINE_MPRV_READ_MXR(mprv_read_mxr_u64, uint64_t, ld) 69 DEFINE_MPRV_READ_MXR(mprv_read_mxr_long, long, ld) 70 DEFINE_MPRV_READ_MXR(mprv_read_mxr_ulong, unsigned long, ld) 71 DEFINE_MPRV_WRITE(mprv_write_u8, uint8_t, sb) 72 DEFINE_MPRV_WRITE(mprv_write_u16, uint16_t, sh) 73 DEFINE_MPRV_WRITE(mprv_write_u32, uint32_t, sw) 74 DEFINE_MPRV_WRITE(mprv_write_u64, uint64_t, sd) 75 DEFINE_MPRV_WRITE(mprv_write_long, long, sd) 76 DEFINE_MPRV_WRITE(mprv_write_ulong, unsigned long, sd) 77 78 #if __riscv_xlen == 32 79 DEFINE_MPRV_READ(mprv_read_uintptr_t, uintptr_t, lw) 80 DEFINE_MPRV_READ(mprv_write_uintptr_t, uintptr_t, sw) 81 #elif __riscv_xlen == 64 82 DEFINE_MPRV_READ(mprv_read_uintptr_t, uintptr_t, ld) 83 DEFINE_MPRV_READ(mprv_write_uintptr_t, uintptr_t, sd) 84 #endif 85 86 #undef DEFINE_MPRV_READ_FLAGS 87 #undef DEFINE_MPRV_READ 88 #undef DEFINE_MPRV_READ_MXR 89 #undef DEFINE_MPRV_WRITE 90 91 #endif 92