b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
| 2 | /* |
| 3 | * linux/arch/arm/lib/copy_from_user.S |
| 4 | * |
| 5 | * Author: Nicolas Pitre |
| 6 | * Created: Sep 29, 2005 |
| 7 | * Copyright: MontaVista Software, Inc. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/linkage.h> |
| 11 | #include <asm/assembler.h> |
| 12 | #include <asm/unwind.h> |
| 13 | |
| 14 | /* |
| 15 | * Prototype: |
| 16 | * |
| 17 | * size_t arm_copy_from_user(void *to, const void *from, size_t n) |
| 18 | * |
| 19 | * Purpose: |
| 20 | * |
| 21 | * copy a block to kernel memory from user memory |
| 22 | * |
| 23 | * Params: |
| 24 | * |
| 25 | * to = kernel memory |
| 26 | * from = user memory |
| 27 | * n = number of bytes to copy |
| 28 | * |
| 29 | * Return value: |
| 30 | * |
| 31 | * Number of bytes NOT copied. |
| 32 | */ |
| 33 | |
| 34 | #ifdef CONFIG_CPU_USE_DOMAINS |
| 35 | |
| 36 | #ifndef CONFIG_THUMB2_KERNEL |
| 37 | #define LDR1W_SHIFT 0 |
| 38 | #else |
| 39 | #define LDR1W_SHIFT 1 |
| 40 | #endif |
| 41 | |
| 42 | .macro ldr1w ptr reg abort |
| 43 | ldrusr \reg, \ptr, 4, abort=\abort |
| 44 | .endm |
| 45 | |
| 46 | .macro ldr4w ptr reg1 reg2 reg3 reg4 abort |
| 47 | ldr1w \ptr, \reg1, \abort |
| 48 | ldr1w \ptr, \reg2, \abort |
| 49 | ldr1w \ptr, \reg3, \abort |
| 50 | ldr1w \ptr, \reg4, \abort |
| 51 | .endm |
| 52 | |
| 53 | .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort |
| 54 | ldr4w \ptr, \reg1, \reg2, \reg3, \reg4, \abort |
| 55 | ldr4w \ptr, \reg5, \reg6, \reg7, \reg8, \abort |
| 56 | .endm |
| 57 | |
| 58 | #else |
| 59 | |
| 60 | #define LDR1W_SHIFT 0 |
| 61 | |
| 62 | .macro ldr1w ptr reg abort |
| 63 | USERL(\abort, W(ldr) \reg, [\ptr], #4) |
| 64 | .endm |
| 65 | |
| 66 | .macro ldr4w ptr reg1 reg2 reg3 reg4 abort |
| 67 | USERL(\abort, ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4}) |
| 68 | .endm |
| 69 | |
| 70 | .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort |
| 71 | USERL(\abort, ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}) |
| 72 | .endm |
| 73 | |
| 74 | #endif /* CONFIG_CPU_USE_DOMAINS */ |
| 75 | |
| 76 | .macro ldr1b ptr reg cond=al abort |
| 77 | ldrusr \reg, \ptr, 1, \cond, abort=\abort |
| 78 | .endm |
| 79 | |
| 80 | #define STR1W_SHIFT 0 |
| 81 | |
| 82 | .macro str1w ptr reg abort |
| 83 | W(str) \reg, [\ptr], #4 |
| 84 | .endm |
| 85 | |
| 86 | .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort |
| 87 | stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8} |
| 88 | .endm |
| 89 | |
| 90 | .macro str1b ptr reg cond=al abort |
| 91 | strb\cond \reg, [\ptr], #1 |
| 92 | .endm |
| 93 | |
| 94 | .macro enter reg1 reg2 |
| 95 | mov r3, #0 |
| 96 | stmdb sp!, {r0, r2, r3, \reg1, \reg2} |
| 97 | .endm |
| 98 | |
| 99 | .macro usave reg1 reg2 |
| 100 | UNWIND( .save {r0, r2, r3, \reg1, \reg2} ) |
| 101 | .endm |
| 102 | |
| 103 | .macro exit reg1 reg2 |
| 104 | add sp, sp, #8 |
| 105 | ldmfd sp!, {r0, \reg1, \reg2} |
| 106 | .endm |
| 107 | |
| 108 | .text |
| 109 | |
| 110 | ENTRY(arm_copy_from_user) |
| 111 | #ifdef CONFIG_CPU_SPECTRE |
| 112 | get_thread_info r3 |
| 113 | ldr r3, [r3, #TI_ADDR_LIMIT] |
| 114 | uaccess_mask_range_ptr r1, r2, r3, ip |
| 115 | #endif |
| 116 | |
| 117 | #include "copy_template.S" |
| 118 | |
| 119 | ENDPROC(arm_copy_from_user) |
| 120 | |
| 121 | .pushsection .text.fixup,"ax" |
| 122 | .align 0 |
| 123 | copy_abort_preamble |
| 124 | ldmfd sp!, {r1, r2, r3} |
| 125 | sub r0, r0, r1 |
| 126 | rsb r0, r0, r2 |
| 127 | copy_abort_end |
| 128 | .popsection |
| 129 | |