diff options
Diffstat (limited to 'arch/nios2/mm/uaccess.c')
| -rw-r--r-- | arch/nios2/mm/uaccess.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/arch/nios2/mm/uaccess.c b/arch/nios2/mm/uaccess.c new file mode 100644 index 000000000000..7663e156ff4f --- /dev/null +++ b/arch/nios2/mm/uaccess.c @@ -0,0 +1,163 @@ +/* + * 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. + * + * Copyright (C) 2009, Wind River Systems Inc + * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com + */ + +#include <linux/export.h> +#include <linux/uaccess.h> + +asm(".global __copy_from_user\n" + " .type __copy_from_user, @function\n" + "__copy_from_user:\n" + " movi r2,7\n" + " mov r3,r4\n" + " bge r2,r6,1f\n" + " xor r2,r4,r5\n" + " andi r2,r2,3\n" + " movi r7,3\n" + " beq r2,zero,4f\n" + "1: addi r6,r6,-1\n" + " movi r2,-1\n" + " beq r6,r2,3f\n" + " mov r7,r2\n" + "2: ldbu r2,0(r5)\n" + " addi r6,r6,-1\n" + " addi r5,r5,1\n" + " stb r2,0(r3)\n" + " addi r3,r3,1\n" + " bne r6,r7,2b\n" + "3:\n" + " addi r2,r6,1\n" + " ret\n" + "13:mov r2,r6\n" + " ret\n" + "4: andi r2,r4,1\n" + " cmpeq r2,r2,zero\n" + " beq r2,zero,7f\n" + "5: andi r2,r3,2\n" + " beq r2,zero,6f\n" + "9: ldhu r2,0(r5)\n" + " addi r6,r6,-2\n" + " addi r5,r5,2\n" + " sth r2,0(r3)\n" + " addi r3,r3,2\n" + "6: bge r7,r6,1b\n" + "10:ldw r2,0(r5)\n" + " addi r6,r6,-4\n" + " addi r5,r5,4\n" + " stw r2,0(r3)\n" + " addi r3,r3,4\n" + " br 6b\n" + "7: ldbu r2,0(r5)\n" + " addi r6,r6,-1\n" + " addi r5,r5,1\n" + " addi r3,r4,1\n" + " stb r2,0(r4)\n" + " br 5b\n" + ".section __ex_table,\"a\"\n" + ".word 2b,3b\n" + ".word 9b,13b\n" + ".word 10b,13b\n" + ".word 7b,13b\n" + ".previous\n" + ); +EXPORT_SYMBOL(__copy_from_user); + +asm( + " .global __copy_to_user\n" + " .type __copy_to_user, @function\n" + "__copy_to_user:\n" + " movi r2,7\n" + " mov r3,r4\n" + " bge r2,r6,1f\n" + " xor r2,r4,r5\n" + " andi r2,r2,3\n" + " movi r7,3\n" + " beq r2,zero,4f\n" + /* Bail if we try to copy zero bytes */ + "1: addi r6,r6,-1\n" + " movi r2,-1\n" + " beq r6,r2,3f\n" + /* Copy byte by byte for small copies and if src^dst != 0 */ + " mov r7,r2\n" + "2: ldbu r2,0(r5)\n" + " addi r5,r5,1\n" + "9: stb r2,0(r3)\n" + " addi r6,r6,-1\n" + " addi r3,r3,1\n" + " bne r6,r7,2b\n" + "3: addi r2,r6,1\n" + " ret\n" + "13:mov r2,r6\n" + " ret\n" + /* If 'to' is an odd address byte copy */ + "4: andi r2,r4,1\n" + " cmpeq r2,r2,zero\n" + " beq r2,zero,7f\n" + /* If 'to' is not divideable by four copy halfwords */ + "5: andi r2,r3,2\n" + " beq r2,zero,6f\n" + " ldhu r2,0(r5)\n" + " addi r5,r5,2\n" + "10:sth r2,0(r3)\n" + " addi r6,r6,-2\n" + " addi r3,r3,2\n" + /* Copy words */ + "6: bge r7,r6,1b\n" + " ldw r2,0(r5)\n" + " addi r5,r5,4\n" + "11:stw r2,0(r3)\n" + " addi r6,r6,-4\n" + " addi r3,r3,4\n" + " br 6b\n" + /* Copy remaining bytes */ + "7: ldbu r2,0(r5)\n" + " addi r5,r5,1\n" + " addi r3,r4,1\n" + "12: stb r2,0(r4)\n" + " addi r6,r6,-1\n" + " br 5b\n" + ".section __ex_table,\"a\"\n" + ".word 9b,3b\n" + ".word 10b,13b\n" + ".word 11b,13b\n" + ".word 12b,13b\n" + ".previous\n"); +EXPORT_SYMBOL(__copy_to_user); + +long strncpy_from_user(char *__to, const char __user *__from, long __len) +{ + int l = strnlen_user(__from, __len); + int is_zt = 1; + + if (l > __len) { + is_zt = 0; + l = __len; + } + + if (l == 0 || copy_from_user(__to, __from, l)) + return -EFAULT; + + if (is_zt) + l--; + return l; +} + +long strnlen_user(const char __user *s, long n) +{ + long i; + + for (i = 0; i < n; i++) { + char c; + + if (get_user(c, s + i) == -EFAULT) + return 0; + if (c == 0) + return i + 1; + } + return n + 1; +} |