| // SPDX-License-Identifier: GPL-2.0 | |
| // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. | |
| #include <linux/uaccess.h> | |
| #include <linux/types.h> | |
| unsigned long raw_copy_from_user(void *to, const void *from, | |
| unsigned long n) | |
| { | |
| ___copy_from_user(to, from, n); | |
| return n; | |
| } | |
| EXPORT_SYMBOL(raw_copy_from_user); | |
| unsigned long raw_copy_to_user(void *to, const void *from, | |
| unsigned long n) | |
| { | |
| ___copy_to_user(to, from, n); | |
| return n; | |
| } | |
| EXPORT_SYMBOL(raw_copy_to_user); | |
| /* | |
| * copy a null terminated string from userspace. | |
| */ | |
| #define __do_strncpy_from_user(dst, src, count, res) \ | |
| do { \ | |
| int tmp; \ | |
| long faultres; \ | |
| asm volatile( \ | |
| " cmpnei %3, 0 \n" \ | |
| " bf 4f \n" \ | |
| "1: cmpnei %1, 0 \n" \ | |
| " bf 5f \n" \ | |
| "2: ldb %4, (%3, 0) \n" \ | |
| " stb %4, (%2, 0) \n" \ | |
| " cmpnei %4, 0 \n" \ | |
| " bf 3f \n" \ | |
| " addi %3, 1 \n" \ | |
| " addi %2, 1 \n" \ | |
| " subi %1, 1 \n" \ | |
| " br 1b \n" \ | |
| "3: subu %0, %1 \n" \ | |
| " br 5f \n" \ | |
| "4: mov %0, %5 \n" \ | |
| " br 5f \n" \ | |
| ".section __ex_table, \"a\" \n" \ | |
| ".align 2 \n" \ | |
| ".long 2b, 4b \n" \ | |
| ".previous \n" \ | |
| "5: \n" \ | |
| : "=r"(res), "=r"(count), "=r"(dst), \ | |
| "=r"(src), "=r"(tmp), "=r"(faultres) \ | |
| : "5"(-EFAULT), "0"(count), "1"(count), \ | |
| "2"(dst), "3"(src) \ | |
| : "memory", "cc"); \ | |
| } while (0) | |
| /* | |
| * __strncpy_from_user: - Copy a NUL terminated string from userspace, | |
| * with less checking. | |
| * @dst: Destination address, in kernel space. This buffer must be at | |
| * least @count bytes long. | |
| * @src: Source address, in user space. | |
| * @count: Maximum number of bytes to copy, including the trailing NUL. | |
| * | |
| * Copies a NUL-terminated string from userspace to kernel space. | |
| * Caller must check the specified block with access_ok() before calling | |
| * this function. | |
| * | |
| * On success, returns the length of the string (not including the trailing | |
| * NUL). | |
| * | |
| * If access to userspace fails, returns -EFAULT (some data may have been | |
| * copied). | |
| * | |
| * If @count is smaller than the length of the string, copies @count bytes | |
| * and returns @count. | |
| */ | |
| long __strncpy_from_user(char *dst, const char *src, long count) | |
| { | |
| long res; | |
| __do_strncpy_from_user(dst, src, count, res); | |
| return res; | |
| } | |
| EXPORT_SYMBOL(__strncpy_from_user); | |
| /* | |
| * strncpy_from_user: - Copy a NUL terminated string from userspace. | |
| * @dst: Destination address, in kernel space. This buffer must be at | |
| * least @count bytes long. | |
| * @src: Source address, in user space. | |
| * @count: Maximum number of bytes to copy, including the trailing NUL. | |
| * | |
| * Copies a NUL-terminated string from userspace to kernel space. | |
| * | |
| * On success, returns the length of the string (not including the trailing | |
| * NUL). | |
| * | |
| * If access to userspace fails, returns -EFAULT (some data may have been | |
| * copied). | |
| * | |
| * If @count is smaller than the length of the string, copies @count bytes | |
| * and returns @count. | |
| */ | |
| long strncpy_from_user(char *dst, const char *src, long count) | |
| { | |
| long res = -EFAULT; | |
| if (access_ok(src, 1)) | |
| __do_strncpy_from_user(dst, src, count, res); | |
| return res; | |
| } | |
| EXPORT_SYMBOL(strncpy_from_user); | |
| /* | |
| * strlen_user: - Get the size of a string in user space. | |
| * @str: The string to measure. | |
| * @n: The maximum valid length | |
| * | |
| * Get the size of a NUL-terminated string in user space. | |
| * | |
| * Returns the size of the string INCLUDING the terminating NUL. | |
| * On exception, returns 0. | |
| * If the string is too long, returns a value greater than @n. | |
| */ | |
| long strnlen_user(const char *s, long n) | |
| { | |
| unsigned long res, tmp; | |
| if (s == NULL) | |
| return 0; | |
| asm volatile( | |
| " cmpnei %1, 0 \n" | |
| " bf 3f \n" | |
| "1: cmpnei %0, 0 \n" | |
| " bf 3f \n" | |
| "2: ldb %3, (%1, 0) \n" | |
| " cmpnei %3, 0 \n" | |
| " bf 3f \n" | |
| " subi %0, 1 \n" | |
| " addi %1, 1 \n" | |
| " br 1b \n" | |
| "3: subu %2, %0 \n" | |
| " addi %2, 1 \n" | |
| " br 5f \n" | |
| "4: movi %0, 0 \n" | |
| " br 5f \n" | |
| ".section __ex_table, \"a\" \n" | |
| ".align 2 \n" | |
| ".long 2b, 4b \n" | |
| ".previous \n" | |
| "5: \n" | |
| : "=r"(n), "=r"(s), "=r"(res), "=r"(tmp) | |
| : "0"(n), "1"(s), "2"(n) | |
| : "memory", "cc"); | |
| return res; | |
| } | |
| EXPORT_SYMBOL(strnlen_user); | |
| #define __do_clear_user(addr, size) \ | |
| do { \ | |
| int __d0, zvalue, tmp; \ | |
| \ | |
| asm volatile( \ | |
| "0: cmpnei %1, 0 \n" \ | |
| " bf 7f \n" \ | |
| " mov %3, %1 \n" \ | |
| " andi %3, 3 \n" \ | |
| " cmpnei %3, 0 \n" \ | |
| " bf 1f \n" \ | |
| " br 5f \n" \ | |
| "1: cmplti %0, 32 \n" /* 4W */ \ | |
| " bt 3f \n" \ | |
| "8: stw %2, (%1, 0) \n" \ | |
| "10: stw %2, (%1, 4) \n" \ | |
| "11: stw %2, (%1, 8) \n" \ | |
| "12: stw %2, (%1, 12) \n" \ | |
| "13: stw %2, (%1, 16) \n" \ | |
| "14: stw %2, (%1, 20) \n" \ | |
| "15: stw %2, (%1, 24) \n" \ | |
| "16: stw %2, (%1, 28) \n" \ | |
| " addi %1, 32 \n" \ | |
| " subi %0, 32 \n" \ | |
| " br 1b \n" \ | |
| "3: cmplti %0, 4 \n" /* 1W */ \ | |
| " bt 5f \n" \ | |
| "4: stw %2, (%1, 0) \n" \ | |
| " addi %1, 4 \n" \ | |
| " subi %0, 4 \n" \ | |
| " br 3b \n" \ | |
| "5: cmpnei %0, 0 \n" /* 1B */ \ | |
| "9: bf 7f \n" \ | |
| "6: stb %2, (%1, 0) \n" \ | |
| " addi %1, 1 \n" \ | |
| " subi %0, 1 \n" \ | |
| " br 5b \n" \ | |
| ".section __ex_table,\"a\" \n" \ | |
| ".align 2 \n" \ | |
| ".long 8b, 9b \n" \ | |
| ".long 10b, 9b \n" \ | |
| ".long 11b, 9b \n" \ | |
| ".long 12b, 9b \n" \ | |
| ".long 13b, 9b \n" \ | |
| ".long 14b, 9b \n" \ | |
| ".long 15b, 9b \n" \ | |
| ".long 16b, 9b \n" \ | |
| ".long 4b, 9b \n" \ | |
| ".long 6b, 9b \n" \ | |
| ".previous \n" \ | |
| "7: \n" \ | |
| : "=r"(size), "=r" (__d0), \ | |
| "=r"(zvalue), "=r"(tmp) \ | |
| : "0"(size), "1"(addr), "2"(0) \ | |
| : "memory", "cc"); \ | |
| } while (0) | |
| /* | |
| * clear_user: - Zero a block of memory in user space. | |
| * @to: Destination address, in user space. | |
| * @n: Number of bytes to zero. | |
| * | |
| * Zero a block of memory in user space. | |
| * | |
| * Returns number of bytes that could not be cleared. | |
| * On success, this will be zero. | |
| */ | |
| unsigned long | |
| clear_user(void __user *to, unsigned long n) | |
| { | |
| if (access_ok(to, n)) | |
| __do_clear_user(to, n); | |
| return n; | |
| } | |
| EXPORT_SYMBOL(clear_user); | |
| /* | |
| * __clear_user: - Zero a block of memory in user space, with less checking. | |
| * @to: Destination address, in user space. | |
| * @n: Number of bytes to zero. | |
| * | |
| * Zero a block of memory in user space. Caller must check | |
| * the specified block with access_ok() before calling this function. | |
| * | |
| * Returns number of bytes that could not be cleared. | |
| * On success, this will be zero. | |
| */ | |
| unsigned long | |
| __clear_user(void __user *to, unsigned long n) | |
| { | |
| __do_clear_user(to, n); | |
| return n; | |
| } | |
| EXPORT_SYMBOL(__clear_user); |