diff options
| author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
| commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
| tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/lib/getuser.S | |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/arm/lib/getuser.S')
| -rw-r--r-- | arch/arm/lib/getuser.S | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/arch/arm/lib/getuser.S b/arch/arm/lib/getuser.S new file mode 100644 index 000000000000..64aa6f4fe5e4 --- /dev/null +++ b/arch/arm/lib/getuser.S @@ -0,0 +1,78 @@ +/* + * linux/arch/arm/lib/getuser.S + * + * Copyright (C) 2001 Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Idea from x86 version, (C) Copyright 1998 Linus Torvalds + * + * These functions have a non-standard call interface to make them more + * efficient, especially as they return an error value in addition to + * the "real" return value. + * + * __get_user_X + * + * Inputs: r0 contains the address + * Outputs: r0 is the error code + * r2, r3 contains the zero-extended value + * lr corrupted + * + * No other registers must be altered. (see include/asm-arm/uaccess.h + * for specific ASM register usage). + * + * Note that ADDR_LIMIT is either 0 or 0xc0000000. + * Note also that it is intended that __get_user_bad is not global. + */ +#include <asm/constants.h> +#include <asm/thread_info.h> +#include <asm/errno.h> + + .global __get_user_1 +__get_user_1: +1: ldrbt r2, [r0] + mov r0, #0 + mov pc, lr + + .global __get_user_2 +__get_user_2: +2: ldrbt r2, [r0], #1 +3: ldrbt r3, [r0] +#ifndef __ARMEB__ + orr r2, r2, r3, lsl #8 +#else + orr r2, r3, r2, lsl #8 +#endif + mov r0, #0 + mov pc, lr + + .global __get_user_4 +__get_user_4: +4: ldrt r2, [r0] + mov r0, #0 + mov pc, lr + + .global __get_user_8 +__get_user_8: +5: ldrt r2, [r0], #4 +6: ldrt r3, [r0] + mov r0, #0 + mov pc, lr + +__get_user_bad_8: + mov r3, #0 +__get_user_bad: + mov r2, #0 + mov r0, #-EFAULT + mov pc, lr + +.section __ex_table, "a" + .long 1b, __get_user_bad + .long 2b, __get_user_bad + .long 3b, __get_user_bad + .long 4b, __get_user_bad + .long 5b, __get_user_bad_8 + .long 6b, __get_user_bad_8 +.previous |