Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm/lib/putuser.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 |
| 13 | * them more efficient, especially as they return an error |
| 14 | * value in addition to the "real" return value. |
| 15 | * |
| 16 | * __put_user_X |
| 17 | * |
| 18 | * Inputs: r0 contains the address |
| 19 | * r2, r3 contains the value |
| 20 | * Outputs: r0 is the error code |
| 21 | * lr corrupted |
| 22 | * |
Russell King | 4baa992 | 2008-08-02 10:55:55 +0100 | [diff] [blame] | 23 | * No other registers must be altered. (see <asm/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 __put_user_bad is not global. |
| 28 | */ |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 29 | #include <linux/linkage.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #include <asm/errno.h> |
| 31 | |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 32 | ENTRY(__put_user_1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | 1: strbt r2, [r0] |
| 34 | mov r0, #0 |
| 35 | mov pc, lr |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 36 | ENDPROC(__put_user_1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 38 | ENTRY(__put_user_2) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | mov ip, r2, lsr #8 |
| 40 | #ifndef __ARMEB__ |
| 41 | 2: strbt r2, [r0], #1 |
| 42 | 3: strbt ip, [r0] |
| 43 | #else |
| 44 | 2: strbt ip, [r0], #1 |
| 45 | 3: strbt r2, [r0] |
| 46 | #endif |
| 47 | mov r0, #0 |
| 48 | mov pc, lr |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 49 | ENDPROC(__put_user_2) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 51 | ENTRY(__put_user_4) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | 4: strt r2, [r0] |
| 53 | mov r0, #0 |
| 54 | mov pc, lr |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 55 | ENDPROC(__put_user_4) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 57 | ENTRY(__put_user_8) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | 5: strt r2, [r0], #4 |
| 59 | 6: strt r3, [r0] |
| 60 | mov r0, #0 |
| 61 | mov pc, lr |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 62 | ENDPROC(__put_user_8) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | |
| 64 | __put_user_bad: |
| 65 | mov r0, #-EFAULT |
| 66 | mov pc, lr |
Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame^] | 67 | ENDPROC(__put_user_bad) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | |
| 69 | .section __ex_table, "a" |
| 70 | .long 1b, __put_user_bad |
| 71 | .long 2b, __put_user_bad |
| 72 | .long 3b, __put_user_bad |
| 73 | .long 4b, __put_user_bad |
| 74 | .long 5b, __put_user_bad |
| 75 | .long 6b, __put_user_bad |
| 76 | .previous |