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Diffstat (limited to 'arch/arm26/lib/getuser.S')
| -rw-r--r-- | arch/arm26/lib/getuser.S | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/arch/arm26/lib/getuser.S b/arch/arm26/lib/getuser.S new file mode 100644 index 000000000000..e6d59b334851 --- /dev/null +++ b/arch/arm26/lib/getuser.S | |||
| @@ -0,0 +1,112 @@ | |||
| 1 | /* | ||
| 2 | * linux/arch/arm26/lib/getuser.S | ||
| 3 | * | ||
| 4 | * Copyright (C) 2001 Russell King | ||
| 5 | * | ||
| 6 | * This program is free software; you can redistribute it and/or modify | ||
| 7 | * it under the terms of the GNU General Public License version 2 as | ||
| 8 | * published by the Free Software Foundation. | ||
| 9 | * | ||
| 10 | * Idea from x86 version, (C) Copyright 1998 Linus Torvalds | ||
| 11 | * | ||
| 12 | * These functions have a non-standard call interface to make them more | ||
| 13 | * efficient, especially as they return an error value in addition to | ||
| 14 | * the "real" return value. | ||
| 15 | * | ||
| 16 | * __get_user_X | ||
| 17 | * | ||
| 18 | * Inputs: r0 contains the address | ||
| 19 | * Outputs: r0 is the error code | ||
| 20 | * r1, r2 contains the zero-extended value | ||
| 21 | * lr corrupted | ||
| 22 | * | ||
| 23 | * No other registers must be altered. (see include/asm-arm/uaccess.h | ||
| 24 | * for specific ASM register usage). | ||
| 25 | * | ||
| 26 | * Note that ADDR_LIMIT is either 0 or 0xc0000000. | ||
| 27 | * Note also that it is intended that __get_user_bad is not global. | ||
| 28 | */ | ||
| 29 | #include <asm/asm_offsets.h> | ||
| 30 | #include <asm/thread_info.h> | ||
| 31 | #include <asm/errno.h> | ||
| 32 | |||
| 33 | .global __get_user_1 | ||
| 34 | __get_user_1: | ||
| 35 | bic r1, sp, #0x1f00 | ||
| 36 | bic r1, r1, #0x00ff | ||
| 37 | str lr, [sp, #-4]! | ||
| 38 | ldr r1, [r1, #TI_ADDR_LIMIT] | ||
| 39 | sub r1, r1, #1 | ||
| 40 | cmp r0, r1 | ||
| 41 | bge __get_user_bad | ||
| 42 | cmp r0, #0x02000000 | ||
| 43 | 1: ldrlsbt r1, [r0] | ||
| 44 | ldrgeb r1, [r0] | ||
| 45 | mov r0, #0 | ||
| 46 | ldmfd sp!, {pc}^ | ||
| 47 | |||
| 48 | .global __get_user_2 | ||
| 49 | __get_user_2: | ||
| 50 | bic r2, sp, #0x1f00 | ||
| 51 | bic r2, r2, #0x00ff | ||
| 52 | str lr, [sp, #-4]! | ||
| 53 | ldr r2, [r2, #TI_ADDR_LIMIT] | ||
| 54 | sub r2, r2, #2 | ||
| 55 | cmp r0, r2 | ||
| 56 | bge __get_user_bad | ||
| 57 | cmp r0, #0x02000000 | ||
| 58 | 2: ldrlsbt r1, [r0], #1 | ||
| 59 | 3: ldrlsbt r2, [r0] | ||
| 60 | ldrgeb r1, [r0], #1 | ||
| 61 | ldrgeb r2, [r0] | ||
| 62 | orr r1, r1, r2, lsl #8 | ||
| 63 | mov r0, #0 | ||
| 64 | ldmfd sp!, {pc}^ | ||
| 65 | |||
| 66 | .global __get_user_4 | ||
| 67 | __get_user_4: | ||
| 68 | bic r1, sp, #0x1f00 | ||
| 69 | bic r1, r1, #0x00ff | ||
| 70 | str lr, [sp, #-4]! | ||
| 71 | ldr r1, [r1, #TI_ADDR_LIMIT] | ||
| 72 | sub r1, r1, #4 | ||
| 73 | cmp r0, r1 | ||
| 74 | bge __get_user_bad | ||
| 75 | cmp r0, #0x02000000 | ||
| 76 | 4: ldrlst r1, [r0] | ||
| 77 | ldrge r1, [r0] | ||
| 78 | mov r0, #0 | ||
| 79 | ldmfd sp!, {pc}^ | ||
| 80 | |||
| 81 | .global __get_user_8 | ||
| 82 | __get_user_8: | ||
| 83 | bic r2, sp, #0x1f00 | ||
| 84 | bic r2, r2, #0x00ff | ||
| 85 | str lr, [sp, #-4]! | ||
| 86 | ldr r2, [r2, #TI_ADDR_LIMIT] | ||
| 87 | sub r2, r2, #8 | ||
| 88 | cmp r0, r2 | ||
| 89 | bge __get_user_bad_8 | ||
| 90 | cmp r0, #0x02000000 | ||
| 91 | 5: ldrlst r1, [r0], #4 | ||
| 92 | 6: ldrlst r2, [r0] | ||
| 93 | ldrge r1, [r0], #4 | ||
| 94 | ldrge r2, [r0] | ||
| 95 | mov r0, #0 | ||
| 96 | ldmfd sp!, {pc}^ | ||
| 97 | |||
| 98 | __get_user_bad_8: | ||
| 99 | mov r2, #0 | ||
| 100 | __get_user_bad: | ||
| 101 | mov r1, #0 | ||
| 102 | mov r0, #-EFAULT | ||
| 103 | ldmfd sp!, {pc}^ | ||
| 104 | |||
| 105 | .section __ex_table, "a" | ||
| 106 | .long 1b, __get_user_bad | ||
| 107 | .long 2b, __get_user_bad | ||
| 108 | .long 3b, __get_user_bad | ||
| 109 | .long 4b, __get_user_bad | ||
| 110 | .long 5b, __get_user_bad_8 | ||
| 111 | .long 6b, __get_user_bad_8 | ||
| 112 | .previous | ||