/* * linux/arch/arm26/lib/putuser.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. * * __put_user_X * * Inputs: r0 contains the address * r1, r2 contains the value * Outputs: r0 is the error code * 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 __put_user_bad is not global. */ #include #include #include .global __put_user_1 __put_user_1: bic r2, sp, #0x1f00 bic r2, r2, #0x00ff str lr, [sp, #-4]! ldr r2, [r2, #TI_ADDR_LIMIT] sub r2, r2, #1 cmp r0, r2 bge __put_user_bad 1: cmp r0, #0x02000000 strlsbt r1, [r0] strgeb r1, [r0] mov r0, #0 ldmfd sp!, {pc}^ .global __put_user_2 __put_user_2: bic r2, sp, #0x1f00 bic r2, r2, #0x00ff str lr, [sp, #-4]! ldr r2, [r2, #TI_ADDR_LIMIT] sub r2, r2, #2 cmp r0, r2 bge __put_user_bad 2: cmp r0, #0x02000000 strlsbt r1, [r0], #1 strgeb r1, [r0], #1 mov r1, r1, lsr #8 3: strlsbt r1, [r0] strgeb r1, [r0] mov r0, #0 ldmfd sp!, {pc}^ .global __put_user_4 __put_user_4: bic r2, sp, #0x1f00 bic r2, r2, #0x00ff str lr, [sp, #-4]! ldr r2, [r2, #TI_ADDR_LIMIT] sub r2, r2, #4 cmp r0, r2 4: bge __put_user_bad cmp r0, #0x02000000 strlst r1, [r0] strge r1, [r0] mov r0, #0 ldmfd sp!, {pc}^ .global __put_user_8 __put_user_8: bic ip, sp, #0x1f00 bic ip, ip, #0x00ff str lr, [sp, #-4]! ldr ip, [ip, #TI_ADDR_LIMIT] sub ip, ip, #8 cmp r0, ip bge __put_user_bad cmp r0, #0x02000000 5: strlst r1, [r0], #4 6: strlst r2, [r0] strge r1, [r0], #4 strge r2, [r0] mov r0, #0 ldmfd sp!, {pc}^ __put_user_bad: mov r0, #-EFAULT mov pc, lr .section __ex_table, "a" .long 1b, __put_user_bad .long 2b, __put_user_bad .long 3b, __put_user_bad .long 4b, __put_user_bad .long 5b, __put_user_bad .long 6b, __put_user_bad .previous