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ca3865bae5
Word copying is used only for aligned addresses. Here is space for improving to use any better copying technique. Look at memcpy implementation. Signed-off-by: Michal Simek <monstr@monstr.eu>
153 lines
2.8 KiB
ArmAsm
153 lines
2.8 KiB
ArmAsm
/*
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* Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
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* Copyright (C) 2009 PetaLogix
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* Copyright (C) 2007 LynuxWorks, Inc.
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*/
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#include <linux/errno.h>
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#include <linux/linkage.h>
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/*
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* int __strncpy_user(char *to, char *from, int len);
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*
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* Returns:
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* -EFAULT for an exception
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* len if we hit the buffer limit
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* bytes copied
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*/
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.text
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.globl __strncpy_user;
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.type __strncpy_user, @function
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.align 4;
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__strncpy_user:
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/*
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* r5 - to
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* r6 - from
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* r7 - len
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* r3 - temp count
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* r4 - temp val
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*/
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addik r3,r7,0 /* temp_count = len */
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beqi r3,3f
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1:
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lbu r4,r6,r0
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sb r4,r5,r0
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addik r3,r3,-1
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beqi r3,2f /* break on len */
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addik r5,r5,1
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bneid r4,1b
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addik r6,r6,1 /* delay slot */
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addik r3,r3,1 /* undo "temp_count--" */
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2:
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rsubk r3,r3,r7 /* temp_count = len - temp_count */
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3:
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rtsd r15,8
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nop
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.size __strncpy_user, . - __strncpy_user
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.section .fixup, "ax"
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.align 2
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4:
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brid 3b
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addik r3,r0, -EFAULT
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.section __ex_table, "a"
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.word 1b,4b
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/*
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* int __strnlen_user(char __user *str, int maxlen);
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*
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* Returns:
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* 0 on error
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* maxlen + 1 if no NUL byte found within maxlen bytes
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* size of the string (including NUL byte)
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*/
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.text
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.globl __strnlen_user;
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.type __strnlen_user, @function
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.align 4;
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__strnlen_user:
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addik r3,r6,0
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beqi r3,3f
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1:
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lbu r4,r5,r0
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beqid r4,2f /* break on NUL */
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addik r3,r3,-1 /* delay slot */
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bneid r3,1b
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addik r5,r5,1 /* delay slot */
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addik r3,r3,-1 /* for break on len */
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2:
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rsubk r3,r3,r6
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3:
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rtsd r15,8
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nop
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.size __strnlen_user, . - __strnlen_user
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.section .fixup,"ax"
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4:
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brid 3b
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addk r3,r0,r0
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.section __ex_table,"a"
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.word 1b,4b
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/*
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* int __copy_tofrom_user(char *to, char *from, int len)
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* Return:
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* 0 on success
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* number of not copied bytes on error
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*/
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.text
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.globl __copy_tofrom_user;
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.type __copy_tofrom_user, @function
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.align 4;
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__copy_tofrom_user:
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/*
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* r5 - to
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* r6 - from
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* r7, r3 - count
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* r4 - tempval
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*/
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beqid r7, 3f /* zero size is not likely */
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andi r3, r7, 0x3 /* filter add count */
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bneid r3, 4f /* if is odd value then byte copying */
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or r3, r5, r6 /* find if is any to/from unaligned */
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andi r3, r3, 0x3 /* mask unaligned */
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bneid r3, 1f /* it is unaligned -> then jump */
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or r3, r0, r0
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/* at least one 4 byte copy */
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5: lw r4, r6, r3
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6: sw r4, r5, r3
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addik r7, r7, -4
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bneid r7, 5b
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addik r3, r3, 4
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addik r3, r7, 0
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rtsd r15, 8
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nop
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4: or r3, r0, r0
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1: lbu r4,r6,r3
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2: sb r4,r5,r3
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addik r7,r7,-1
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bneid r7,1b
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addik r3,r3,1 /* delay slot */
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3:
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addik r3,r7,0
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rtsd r15,8
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nop
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.size __copy_tofrom_user, . - __copy_tofrom_user
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.section __ex_table,"a"
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.word 1b,3b,2b,3b,5b,3b,6b,3b
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