Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * __put_user functions. | |
3 | * | |
4 | * (C) Copyright 2005 Linus Torvalds | |
5cbbc3b1 GC |
5 | * (C) Copyright 2005 Andi Kleen |
6 | * (C) Copyright 2008 Glauber Costa | |
1da177e4 LT |
7 | * |
8 | * These functions have a non-standard call interface | |
9 | * to make them more efficient, especially as they | |
10 | * return an error value in addition to the "real" | |
11 | * return value. | |
12 | */ | |
00e065ea JB |
13 | #include <linux/linkage.h> |
14 | #include <asm/dwarf2.h> | |
1da177e4 | 15 | #include <asm/thread_info.h> |
5cbbc3b1 | 16 | #include <asm/errno.h> |
2528de43 | 17 | #include <asm/asm.h> |
63bcff2a | 18 | #include <asm/smap.h> |
1da177e4 LT |
19 | |
20 | ||
21 | /* | |
22 | * __put_user_X | |
23 | * | |
24 | * Inputs: %eax[:%edx] contains the data | |
25 | * %ecx contains the address | |
26 | * | |
27 | * Outputs: %eax is error code (0 or -EFAULT) | |
28 | * | |
29 | * These functions should not modify any other registers, | |
30 | * as they get called from within inline assembly. | |
31 | */ | |
32 | ||
00e065ea | 33 | #define ENTER CFI_STARTPROC ; \ |
2528de43 | 34 | GET_THREAD_INFO(%_ASM_BX) |
63bcff2a PA |
35 | #define EXIT ASM_CLAC ; \ |
36 | ret ; \ | |
00e065ea | 37 | CFI_ENDPROC |
1da177e4 LT |
38 | |
39 | .text | |
00e065ea | 40 | ENTRY(__put_user_1) |
1da177e4 | 41 | ENTER |
2528de43 | 42 | cmp TI_addr_limit(%_ASM_BX),%_ASM_CX |
1da177e4 | 43 | jae bad_put_user |
63bcff2a | 44 | ASM_STAC |
2528de43 | 45 | 1: movb %al,(%_ASM_CX) |
efea505d | 46 | xor %eax,%eax |
1da177e4 | 47 | EXIT |
00e065ea | 48 | ENDPROC(__put_user_1) |
1da177e4 | 49 | |
00e065ea | 50 | ENTRY(__put_user_2) |
1da177e4 | 51 | ENTER |
2528de43 GC |
52 | mov TI_addr_limit(%_ASM_BX),%_ASM_BX |
53 | sub $1,%_ASM_BX | |
54 | cmp %_ASM_BX,%_ASM_CX | |
1da177e4 | 55 | jae bad_put_user |
63bcff2a | 56 | ASM_STAC |
2528de43 | 57 | 2: movw %ax,(%_ASM_CX) |
efea505d | 58 | xor %eax,%eax |
1da177e4 | 59 | EXIT |
00e065ea | 60 | ENDPROC(__put_user_2) |
1da177e4 | 61 | |
00e065ea | 62 | ENTRY(__put_user_4) |
1da177e4 | 63 | ENTER |
2528de43 GC |
64 | mov TI_addr_limit(%_ASM_BX),%_ASM_BX |
65 | sub $3,%_ASM_BX | |
66 | cmp %_ASM_BX,%_ASM_CX | |
1da177e4 | 67 | jae bad_put_user |
63bcff2a | 68 | ASM_STAC |
2528de43 | 69 | 3: movl %eax,(%_ASM_CX) |
efea505d | 70 | xor %eax,%eax |
1da177e4 | 71 | EXIT |
00e065ea | 72 | ENDPROC(__put_user_4) |
1da177e4 | 73 | |
00e065ea | 74 | ENTRY(__put_user_8) |
1da177e4 | 75 | ENTER |
2528de43 GC |
76 | mov TI_addr_limit(%_ASM_BX),%_ASM_BX |
77 | sub $7,%_ASM_BX | |
78 | cmp %_ASM_BX,%_ASM_CX | |
1da177e4 | 79 | jae bad_put_user |
63bcff2a | 80 | ASM_STAC |
5cbbc3b1 GC |
81 | 4: mov %_ASM_AX,(%_ASM_CX) |
82 | #ifdef CONFIG_X86_32 | |
2528de43 | 83 | 5: movl %edx,4(%_ASM_CX) |
5cbbc3b1 | 84 | #endif |
efea505d | 85 | xor %eax,%eax |
1da177e4 | 86 | EXIT |
00e065ea | 87 | ENDPROC(__put_user_8) |
1da177e4 LT |
88 | |
89 | bad_put_user: | |
268cf048 | 90 | CFI_STARTPROC |
5cbbc3b1 | 91 | movl $-EFAULT,%eax |
1da177e4 | 92 | EXIT |
00e065ea | 93 | END(bad_put_user) |
1da177e4 | 94 | |
a53a96e5 PA |
95 | _ASM_EXTABLE(1b,bad_put_user) |
96 | _ASM_EXTABLE(2b,bad_put_user) | |
97 | _ASM_EXTABLE(3b,bad_put_user) | |
98 | _ASM_EXTABLE(4b,bad_put_user) | |
5cbbc3b1 | 99 | #ifdef CONFIG_X86_32 |
a53a96e5 | 100 | _ASM_EXTABLE(5b,bad_put_user) |
5cbbc3b1 | 101 | #endif |