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| /*
| * Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
| * Copyright (C) 2009 PetaLogix
| * Copyright (C) 2007 LynuxWorks, Inc.
| *
| * This file is subject to the terms and conditions of the GNU General Public
| * License. See the file "COPYING" in the main directory of this archive
| * for more details.
| */
|
| #include <linux/errno.h>
| #include <linux/linkage.h>
| #include <asm/page.h>
|
| /*
| * int __strncpy_user(char *to, char *from, int len);
| *
| * Returns:
| * -EFAULT for an exception
| * len if we hit the buffer limit
| * bytes copied
| */
|
| .text
| .globl __strncpy_user;
| .type __strncpy_user, @function
| .align 4;
| __strncpy_user:
|
| /*
| * r5 - to
| * r6 - from
| * r7 - len
| * r3 - temp count
| * r4 - temp val
| */
| beqid r7,3f
| addik r3,r7,0 /* temp_count = len */
| 1:
| lbu r4,r6,r0
| beqid r4,2f
| sb r4,r5,r0
|
| addik r5,r5,1
| addik r6,r6,1 /* delay slot */
|
| addik r3,r3,-1
| bnei r3,1b /* break on len */
| 2:
| rsubk r3,r3,r7 /* temp_count = len - temp_count */
| 3:
| rtsd r15,8
| nop
| .size __strncpy_user, . - __strncpy_user
|
| .section .fixup, "ax"
| .align 2
| 4:
| brid 3b
| addik r3,r0, -EFAULT
|
| .section __ex_table, "a"
| .word 1b,4b
|
| /*
| * int __strnlen_user(char __user *str, int maxlen);
| *
| * Returns:
| * 0 on error
| * maxlen + 1 if no NUL byte found within maxlen bytes
| * size of the string (including NUL byte)
| */
|
| .text
| .globl __strnlen_user;
| .type __strnlen_user, @function
| .align 4;
| __strnlen_user:
| beqid r6,3f
| addik r3,r6,0
| 1:
| lbu r4,r5,r0
| beqid r4,2f /* break on NUL */
| addik r3,r3,-1 /* delay slot */
|
| bneid r3,1b
| addik r5,r5,1 /* delay slot */
|
| addik r3,r3,-1 /* for break on len */
| 2:
| rsubk r3,r3,r6
| 3:
| rtsd r15,8
| nop
| .size __strnlen_user, . - __strnlen_user
|
| .section .fixup,"ax"
| 4:
| brid 3b
| addk r3,r0,r0
|
| .section __ex_table,"a"
| .word 1b,4b
|
| /* Loop unrolling for __copy_tofrom_user */
| #define COPY(offset) \
| 1: lwi r4 , r6, 0x0000 + offset; \
| 2: lwi r19, r6, 0x0004 + offset; \
| 3: lwi r20, r6, 0x0008 + offset; \
| 4: lwi r21, r6, 0x000C + offset; \
| 5: lwi r22, r6, 0x0010 + offset; \
| 6: lwi r23, r6, 0x0014 + offset; \
| 7: lwi r24, r6, 0x0018 + offset; \
| 8: lwi r25, r6, 0x001C + offset; \
| 9: swi r4 , r5, 0x0000 + offset; \
| 10: swi r19, r5, 0x0004 + offset; \
| 11: swi r20, r5, 0x0008 + offset; \
| 12: swi r21, r5, 0x000C + offset; \
| 13: swi r22, r5, 0x0010 + offset; \
| 14: swi r23, r5, 0x0014 + offset; \
| 15: swi r24, r5, 0x0018 + offset; \
| 16: swi r25, r5, 0x001C + offset; \
| .section __ex_table,"a"; \
| .word 1b, 33f; \
| .word 2b, 33f; \
| .word 3b, 33f; \
| .word 4b, 33f; \
| .word 5b, 33f; \
| .word 6b, 33f; \
| .word 7b, 33f; \
| .word 8b, 33f; \
| .word 9b, 33f; \
| .word 10b, 33f; \
| .word 11b, 33f; \
| .word 12b, 33f; \
| .word 13b, 33f; \
| .word 14b, 33f; \
| .word 15b, 33f; \
| .word 16b, 33f; \
| .text
|
| #define COPY_80(offset) \
| COPY(0x00 + offset);\
| COPY(0x20 + offset);\
| COPY(0x40 + offset);\
| COPY(0x60 + offset);
|
| /*
| * int __copy_tofrom_user(char *to, char *from, int len)
| * Return:
| * 0 on success
| * number of not copied bytes on error
| */
| .text
| .globl __copy_tofrom_user;
| .type __copy_tofrom_user, @function
| .align 4;
| __copy_tofrom_user:
| /*
| * r5 - to
| * r6 - from
| * r7, r3 - count
| * r4 - tempval
| */
| beqid r7, 0f /* zero size is not likely */
| or r3, r5, r6 /* find if is any to/from unaligned */
| or r3, r3, r7 /* find if count is unaligned */
| andi r3, r3, 0x3 /* mask last 3 bits */
| bneid r3, bu1 /* if r3 is not zero then byte copying */
| or r3, r0, r0
|
| rsubi r3, r7, PAGE_SIZE /* detect PAGE_SIZE */
| beqid r3, page;
| or r3, r0, r0
|
| w1: lw r4, r6, r3 /* at least one 4 byte copy */
| w2: sw r4, r5, r3
| addik r7, r7, -4
| bneid r7, w1
| addik r3, r3, 4
| addik r3, r7, 0
| rtsd r15, 8
| nop
|
| .section __ex_table,"a"
| .word w1, 0f;
| .word w2, 0f;
| .text
|
| .align 4 /* Alignment is important to keep icache happy */
| page: /* Create room on stack and save registers for storign values */
| addik r1, r1, -40
| swi r5, r1, 0
| swi r6, r1, 4
| swi r7, r1, 8
| swi r19, r1, 12
| swi r20, r1, 16
| swi r21, r1, 20
| swi r22, r1, 24
| swi r23, r1, 28
| swi r24, r1, 32
| swi r25, r1, 36
| loop: /* r4, r19, r20, r21, r22, r23, r24, r25 are used for storing values */
| /* Loop unrolling to get performance boost */
| COPY_80(0x000);
| COPY_80(0x080);
| COPY_80(0x100);
| COPY_80(0x180);
| /* copy loop */
| addik r6, r6, 0x200
| addik r7, r7, -0x200
| bneid r7, loop
| addik r5, r5, 0x200
|
| /* Restore register content */
| lwi r5, r1, 0
| lwi r6, r1, 4
| lwi r7, r1, 8
| lwi r19, r1, 12
| lwi r20, r1, 16
| lwi r21, r1, 20
| lwi r22, r1, 24
| lwi r23, r1, 28
| lwi r24, r1, 32
| lwi r25, r1, 36
| addik r1, r1, 40
| /* return back */
| addik r3, r0, 0
| rtsd r15, 8
| nop
|
| /* Fault case - return temp count */
| 33:
| addik r3, r7, 0
| /* Restore register content */
| lwi r5, r1, 0
| lwi r6, r1, 4
| lwi r7, r1, 8
| lwi r19, r1, 12
| lwi r20, r1, 16
| lwi r21, r1, 20
| lwi r22, r1, 24
| lwi r23, r1, 28
| lwi r24, r1, 32
| lwi r25, r1, 36
| addik r1, r1, 40
| /* return back */
| rtsd r15, 8
| nop
|
| .align 4 /* Alignment is important to keep icache happy */
| bu1: lbu r4,r6,r3
| bu2: sb r4,r5,r3
| addik r7,r7,-1
| bneid r7,bu1
| addik r3,r3,1 /* delay slot */
| 0:
| addik r3,r7,0
| rtsd r15,8
| nop
| .size __copy_tofrom_user, . - __copy_tofrom_user
|
| .section __ex_table,"a"
| .word bu1, 0b;
| .word bu2, 0b;
| .text
|
|
