projects / mirror_ubuntu-eoan-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 1da177e4 LT |
2 | /* |
| 3 | * __put_user functions. | |
| 4 | * | |
| 5 | * (C) Copyright 2005 Linus Torvalds | |
| 5cbbc3b1 GC |
6 | * (C) Copyright 2005 Andi Kleen |
| 7 | * (C) Copyright 2008 Glauber Costa | |
| 1da177e4 LT |
8 | * |
| 9 | * These functions have a non-standard call interface | |
| 10 | * to make them more efficient, especially as they | |
| 11 | * return an error value in addition to the "real" | |
| 12 | * return value. | |
| 13 | */ | |
| 00e065ea | 14 | #include <linux/linkage.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> |
| 784d5699 | 19 | #include <asm/export.h> |
| 1da177e4 LT |
20 | |
| 21 | ||
| 22 | /* | |
| 23 | * __put_user_X | |
| 24 | * | |
| 25 | * Inputs: %eax[:%edx] contains the data | |
| 26 | * %ecx contains the address | |
| 27 | * | |
| 28 | * Outputs: %eax is error code (0 or -EFAULT) | |
| 29 | * | |
| 30 | * These functions should not modify any other registers, | |
| 31 | * as they get called from within inline assembly. | |
| 32 | */ | |
| 33 | ||
| 13d4ea09 | 34 | #define ENTER mov PER_CPU_VAR(current_task), %_ASM_BX |
| 1da177e4 LT |
35 | |
| 36 | .text | |
| 00e065ea | 37 | ENTRY(__put_user_1) |
| 1da177e4 | 38 | ENTER |
| 13d4ea09 | 39 | cmp TASK_addr_limit(%_ASM_BX),%_ASM_CX |
| 1da177e4 | 40 | jae bad_put_user |
| 63bcff2a | 41 | ASM_STAC |
| 2528de43 | 42 | 1: movb %al,(%_ASM_CX) |
| efea505d | 43 | xor %eax,%eax |
| 82e844a6 JP |
44 | ASM_CLAC |
| 45 | ret | |
| 00e065ea | 46 | ENDPROC(__put_user_1) |
| 784d5699 | 47 | EXPORT_SYMBOL(__put_user_1) |
| 1da177e4 | 48 | |
| 00e065ea | 49 | ENTRY(__put_user_2) |
| 1da177e4 | 50 | ENTER |
| 13d4ea09 | 51 | mov TASK_addr_limit(%_ASM_BX),%_ASM_BX |
| 2528de43 GC |
52 | sub $1,%_ASM_BX |
| 53 | cmp %_ASM_BX,%_ASM_CX | |
| 1da177e4 | 54 | jae bad_put_user |
| 63bcff2a | 55 | ASM_STAC |
| 2528de43 | 56 | 2: movw %ax,(%_ASM_CX) |
| efea505d | 57 | xor %eax,%eax |
| 82e844a6 JP |
58 | ASM_CLAC |
| 59 | ret | |
| 00e065ea | 60 | ENDPROC(__put_user_2) |
| 784d5699 | 61 | EXPORT_SYMBOL(__put_user_2) |
| 1da177e4 | 62 | |
| 00e065ea | 63 | ENTRY(__put_user_4) |
| 1da177e4 | 64 | ENTER |
| 13d4ea09 | 65 | mov TASK_addr_limit(%_ASM_BX),%_ASM_BX |
| 2528de43 GC |
66 | sub $3,%_ASM_BX |
| 67 | cmp %_ASM_BX,%_ASM_CX | |
| 1da177e4 | 68 | jae bad_put_user |
| 63bcff2a | 69 | ASM_STAC |
| 2528de43 | 70 | 3: movl %eax,(%_ASM_CX) |
| efea505d | 71 | xor %eax,%eax |
| 82e844a6 JP |
72 | ASM_CLAC |
| 73 | ret | |
| 00e065ea | 74 | ENDPROC(__put_user_4) |
| 784d5699 | 75 | EXPORT_SYMBOL(__put_user_4) |
| 1da177e4 | 76 | |
| 00e065ea | 77 | ENTRY(__put_user_8) |
| 1da177e4 | 78 | ENTER |
| 13d4ea09 | 79 | mov TASK_addr_limit(%_ASM_BX),%_ASM_BX |
| 2528de43 GC |
80 | sub $7,%_ASM_BX |
| 81 | cmp %_ASM_BX,%_ASM_CX | |
| 1da177e4 | 82 | jae bad_put_user |
| 63bcff2a | 83 | ASM_STAC |
| 5cbbc3b1 GC |
84 | 4: mov %_ASM_AX,(%_ASM_CX) |
| 85 | #ifdef CONFIG_X86_32 | |
| 2528de43 | 86 | 5: movl %edx,4(%_ASM_CX) |
| 5cbbc3b1 | 87 | #endif |
| efea505d | 88 | xor %eax,%eax |
| 82e844a6 JP |
89 | ASM_CLAC |
| 90 | RET | |
| 00e065ea | 91 | ENDPROC(__put_user_8) |
| 784d5699 | 92 | EXPORT_SYMBOL(__put_user_8) |
| 1da177e4 | 93 | |
| 82e844a6 JP |
94 | bad_put_user_clac: |
| 95 | ASM_CLAC | |
| 1da177e4 | 96 | bad_put_user: |
| 5cbbc3b1 | 97 | movl $-EFAULT,%eax |
| 82e844a6 | 98 | RET |
| 1da177e4 | 99 | |
| 82e844a6 JP |
100 | _ASM_EXTABLE_UA(1b, bad_put_user_clac) |
| 101 | _ASM_EXTABLE_UA(2b, bad_put_user_clac) | |
| 102 | _ASM_EXTABLE_UA(3b, bad_put_user_clac) | |
| 103 | _ASM_EXTABLE_UA(4b, bad_put_user_clac) | |
| 5cbbc3b1 | 104 | #ifdef CONFIG_X86_32 |
| 82e844a6 | 105 | _ASM_EXTABLE_UA(5b, bad_put_user_clac) |
| 5cbbc3b1 | 106 | #endif |