1 /*
2 * Copyright (c) 2022-2022 Huawei Device Co., Ltd. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without modification,
5 * are permitted provided that the following conditions are met:
6 *
7 * 1. Redistributions of source code must retain the above copyright notice, this list of
8 * conditions and the following disclaimer.
9 *
10 * 2. Redistributions in binary form must reproduce the above copyright notice, this list
11 * of conditions and the following disclaimer in the documentation and/or other materials
12 * provided with the distribution.
13 *
14 * 3. Neither the name of the copyright holder nor the names of its contributors may be used
15 * to endorse or promote products derived from this software without specific prior written
16 * permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
20 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
22 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
23 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
24 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
25 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
26 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
27 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
28 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #define GNU_SOURCE
32 #include "los_syscall.h"
33 #include "los_context.h"
34 #include "los_task.h"
35 #include "los_debug.h"
36 #include "unistd.h"
37 #include "errno.h"
38
39 #define SYS_CALL_NUM_LIMIT (__NR_syscallend + 1)
40 #define SYS_CALL_NUM_REG_OFFSET 7
41 #define NARG_BITS 4
42 #define NARG_MASK 0x0F
43 #define NARG_PER_BYTE 2
44
45 typedef UINT32 (*SyscallFun1)(UINT32);
46 typedef UINT32 (*SyscallFun2)(UINT32, UINT32);
47 typedef UINT32 (*SyscallFun3)(UINT32, UINT32, UINT32);
48 typedef UINT32 (*SyscallFun4)(UINT32, UINT32, UINT32, UINT32);
49 typedef UINT32 (*SyscallFun5)(UINT32, UINT32, UINT32, UINT32, UINT32);
50 typedef UINT32 (*SyscallFun7)(UINT32, UINT32, UINT32, UINT32, UINT32, UINT32, UINT32);
51
52 static UINTPTR g_syscallHandle[SYS_CALL_NUM_LIMIT] = {0};
53 static UINT8 g_syscallNArgs[(SYS_CALL_NUM_LIMIT + 1) / NARG_PER_BYTE] = {0};
54
OsSyscallHandleInit(void)55 void OsSyscallHandleInit(void)
56 {
57 #define SYSCALL_HAND_DEF(id, fun, rType, nArg) \
58 if ((id) < SYS_CALL_NUM_LIMIT) { \
59 g_syscallHandle[(id)] = (UINTPTR)(fun); \
60 g_syscallNArgs[(id) / NARG_PER_BYTE] |= ((id) & 1) ? (nArg) << NARG_BITS : (nArg); \
61 } \
62
63 #include "syscall_lookup.h"
64 #undef SYSCALL_HAND_DEF
65 }
66
67 /* The SYSCALL ID is in R7 on entry. Parameters follow in R0..R6 */
OsSyscallHandle(UINT32 * args)68 VOID OsSyscallHandle(UINT32 *args)
69 {
70 UINT32 ret;
71 UINT8 nArgs;
72 UINTPTR handle;
73 UINT32 svcNum = (UINT32)args[SYS_CALL_NUM_REG_OFFSET];
74
75 if (svcNum >= SYS_CALL_NUM_LIMIT) {
76 PRINT_ERR("Syscall ID: error %d !!!\n", svcNum);
77 return;
78 }
79
80 handle = g_syscallHandle[svcNum];
81 nArgs = g_syscallNArgs[svcNum / NARG_PER_BYTE]; /* 4bit per nargs */
82 nArgs = (svcNum & 1) ? (nArgs >> NARG_BITS) : (nArgs & NARG_MASK);
83 if ((handle == 0) || (nArgs > ARG_NUM_7)) {
84 PRINT_ERR("Unsupported syscall ID: %d nArgs: %d\n", svcNum, nArgs);
85 args[ARG_NUM_0] = -ENOSYS;
86 return;
87 }
88
89 switch (nArgs) {
90 case ARG_NUM_0:
91 case ARG_NUM_1:
92 ret = (*(SyscallFun1)handle)(args[ARG_NUM_0]);
93 break;
94 case ARG_NUM_2:
95 ret = (*(SyscallFun2)handle)(args[ARG_NUM_0], args[ARG_NUM_1]);
96 break;
97 case ARG_NUM_3:
98 ret = (*(SyscallFun3)handle)(args[ARG_NUM_0], args[ARG_NUM_1], args[ARG_NUM_2]);
99 break;
100 case ARG_NUM_4:
101 ret = (*(SyscallFun4)handle)(args[ARG_NUM_0], args[ARG_NUM_1], args[ARG_NUM_2], args[ARG_NUM_3]);
102 break;
103 case ARG_NUM_5:
104 ret = (*(SyscallFun5)handle)(args[ARG_NUM_0], args[ARG_NUM_1], args[ARG_NUM_2], args[ARG_NUM_3], \
105 args[ARG_NUM_4]);
106 break;
107 default:
108 ret = (*(SyscallFun7)handle)(args[ARG_NUM_0], args[ARG_NUM_1], args[ARG_NUM_2], args[ARG_NUM_3], \
109 args[ARG_NUM_4], args[ARG_NUM_5], args[ARG_NUM_6]);
110 }
111
112 args[ARG_NUM_0] = ret;
113
114 return;
115 }