diff options
Diffstat (limited to 'arch/i386/lib/putuser_32.S')
-rw-r--r-- | arch/i386/lib/putuser_32.S | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/arch/i386/lib/putuser_32.S b/arch/i386/lib/putuser_32.S new file mode 100644 index 000000000000..f58fba109d18 --- /dev/null +++ b/arch/i386/lib/putuser_32.S | |||
@@ -0,0 +1,98 @@ | |||
1 | /* | ||
2 | * __put_user functions. | ||
3 | * | ||
4 | * (C) Copyright 2005 Linus Torvalds | ||
5 | * | ||
6 | * These functions have a non-standard call interface | ||
7 | * to make them more efficient, especially as they | ||
8 | * return an error value in addition to the "real" | ||
9 | * return value. | ||
10 | */ | ||
11 | #include <linux/linkage.h> | ||
12 | #include <asm/dwarf2.h> | ||
13 | #include <asm/thread_info.h> | ||
14 | |||
15 | |||
16 | /* | ||
17 | * __put_user_X | ||
18 | * | ||
19 | * Inputs: %eax[:%edx] contains the data | ||
20 | * %ecx contains the address | ||
21 | * | ||
22 | * Outputs: %eax is error code (0 or -EFAULT) | ||
23 | * | ||
24 | * These functions should not modify any other registers, | ||
25 | * as they get called from within inline assembly. | ||
26 | */ | ||
27 | |||
28 | #define ENTER CFI_STARTPROC ; \ | ||
29 | pushl %ebx ; \ | ||
30 | CFI_ADJUST_CFA_OFFSET 4 ; \ | ||
31 | CFI_REL_OFFSET ebx, 0 ; \ | ||
32 | GET_THREAD_INFO(%ebx) | ||
33 | #define EXIT popl %ebx ; \ | ||
34 | CFI_ADJUST_CFA_OFFSET -4 ; \ | ||
35 | CFI_RESTORE ebx ; \ | ||
36 | ret ; \ | ||
37 | CFI_ENDPROC | ||
38 | |||
39 | .text | ||
40 | ENTRY(__put_user_1) | ||
41 | ENTER | ||
42 | cmpl TI_addr_limit(%ebx),%ecx | ||
43 | jae bad_put_user | ||
44 | 1: movb %al,(%ecx) | ||
45 | xorl %eax,%eax | ||
46 | EXIT | ||
47 | ENDPROC(__put_user_1) | ||
48 | |||
49 | ENTRY(__put_user_2) | ||
50 | ENTER | ||
51 | movl TI_addr_limit(%ebx),%ebx | ||
52 | subl $1,%ebx | ||
53 | cmpl %ebx,%ecx | ||
54 | jae bad_put_user | ||
55 | 2: movw %ax,(%ecx) | ||
56 | xorl %eax,%eax | ||
57 | EXIT | ||
58 | ENDPROC(__put_user_2) | ||
59 | |||
60 | ENTRY(__put_user_4) | ||
61 | ENTER | ||
62 | movl TI_addr_limit(%ebx),%ebx | ||
63 | subl $3,%ebx | ||
64 | cmpl %ebx,%ecx | ||
65 | jae bad_put_user | ||
66 | 3: movl %eax,(%ecx) | ||
67 | xorl %eax,%eax | ||
68 | EXIT | ||
69 | ENDPROC(__put_user_4) | ||
70 | |||
71 | ENTRY(__put_user_8) | ||
72 | ENTER | ||
73 | movl TI_addr_limit(%ebx),%ebx | ||
74 | subl $7,%ebx | ||
75 | cmpl %ebx,%ecx | ||
76 | jae bad_put_user | ||
77 | 4: movl %eax,(%ecx) | ||
78 | 5: movl %edx,4(%ecx) | ||
79 | xorl %eax,%eax | ||
80 | EXIT | ||
81 | ENDPROC(__put_user_8) | ||
82 | |||
83 | bad_put_user: | ||
84 | CFI_STARTPROC simple | ||
85 | CFI_DEF_CFA esp, 2*4 | ||
86 | CFI_OFFSET eip, -1*4 | ||
87 | CFI_OFFSET ebx, -2*4 | ||
88 | movl $-14,%eax | ||
89 | EXIT | ||
90 | END(bad_put_user) | ||
91 | |||
92 | .section __ex_table,"a" | ||
93 | .long 1b,bad_put_user | ||
94 | .long 2b,bad_put_user | ||
95 | .long 3b,bad_put_user | ||
96 | .long 4b,bad_put_user | ||
97 | .long 5b,bad_put_user | ||
98 | .previous | ||