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Diffstat (limited to 'include/asm-blackfin/uaccess.h')
| -rw-r--r-- | include/asm-blackfin/uaccess.h | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/include/asm-blackfin/uaccess.h b/include/asm-blackfin/uaccess.h new file mode 100644 index 0000000..8578166 --- /dev/null +++ b/include/asm-blackfin/uaccess.h @@ -0,0 +1,207 @@ +/* + * U-boot - uaccess.h + * + * Copyright (c) 2005 blackfin.uclinux.org + * + * This file is based on + * Based on: include/asm-m68knommu/uaccess.h + * Changes made by Lineo Inc. May 2001 + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#ifndef __BLACKFIN_UACCESS_H +#define __BLACKFIN_UACCESS_H + +/* + * User space memory access functions + */ +#include <asm/segment.h> +#include <asm/errno.h> + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +/* We let the MMU do all checking */ +static inline int access_ok(int type, const void *addr, unsigned long size) +{ + return ((unsigned long) addr < 0x10f00000); /* need final decision - Tony */ +} + +static inline int verify_area(int type, const void *addr, + unsigned long size) +{ + return access_ok(type, addr, size) ? 0 : -EFAULT; +} + +/* + * The exception table consists of pairs of addresses: the first is the + * address of an instruction that is allowed to fault, and the second is + * the address at which the program should continue. No registers are + * modified, so it is entirely up to the continuation code to figure out + * what to do. + * + * All the routines below use bits of fixup code that are out of line + * with the main instruction path. This means when everything is well, + * we don't even have to jump over them. Further, they do not intrude + * on our cache or tlb entries. + */ + +struct exception_table_entry { + unsigned long insn, fixup; +}; + +/* Returns 0 if exception not found and fixup otherwise. */ +extern unsigned long search_exception_table(unsigned long); + +/* + * These are the main single-value transfer routines. They automatically + * use the right size if we just have the right pointer type. + */ + +#define put_user(x, ptr) \ +({ \ + int __pu_err = 0; \ + typeof(*(ptr)) __pu_val = (x); \ + switch (sizeof (*(ptr))) { \ + case 1: \ + __put_user_asm(__pu_err, __pu_val, ptr, B); \ + break; \ + case 2: \ + __put_user_asm(__pu_err, __pu_val, ptr, W); \ + break; \ + case 4: \ + __put_user_asm(__pu_err, __pu_val, ptr, ); \ + break; \ + default: \ + __pu_err = __put_user_bad(); \ + break; \ + } \ + __pu_err; \ +}) +/* + * [pregs] = dregs ==> 32bits + * H[pregs] = dregs ==> 16bits + * B[pregs] = dregs ==> 8 bits + */ + +#define __put_user(x, ptr) put_user(x, ptr) + +static inline int bad_user_access_length(void) +{ + panic("bad_user_access_length"); + return -1; +} + +#define __put_user_bad() (bad_user_access_length(), (-EFAULT)) + +/* + * Tell gcc we read from memory instead of writing: this is because + * we do not write to any memory gcc knows about, so there are no + * aliasing issues. + */ + +#define __ptr(x) ((unsigned long *)(x)) + +#define __put_user_asm(err,x,ptr,bhw) \ + __asm__ (#bhw"[%1] = %0;\n\t" \ + : /* no outputs */ \ + :"d" (x),"a" (__ptr(ptr)) : "memory") + +#define get_user(x, ptr) \ +({ \ + int __gu_err = 0; \ + typeof(*(ptr)) __gu_val = 0; \ + switch (sizeof(*(ptr))) { \ + case 1: \ + __get_user_asm(__gu_err, __gu_val, ptr, B, "=d",(Z)); \ + break; \ + case 2: \ + __get_user_asm(__gu_err, __gu_val, ptr, W, "=r",(Z)); \ + break; \ + case 4: \ + __get_user_asm(__gu_err, __gu_val, ptr, , "=r",); \ + break; \ + default: \ + __gu_val = 0; \ + __gu_err = __get_user_bad(); \ + break; \ + } \ + (x) = __gu_val; \ + __gu_err; \ +}) + +/* dregs = [pregs] ==> 32bits + * H[pregs] ==> 16bits + * B[pregs] ==> 8 bits + */ + +#define __get_user(x, ptr) get_user(x, ptr) +#define __get_user_bad() (bad_user_access_length(), (-EFAULT)) + +#define __get_user_asm(err,x,ptr,bhw,reg,option) \ + __asm__ ("%0 =" #bhw "[%1]"#option";\n\t" \ + : "=d" (x) \ + : "a" (__ptr(ptr))) + +#define copy_from_user(to, from, n) (memcpy(to, from, n), 0) +#define copy_to_user(to, from, n) (memcpy(to, from, n), 0) + +#define __copy_from_user(to, from, n) copy_from_user(to, from, n) +#define __copy_to_user(to, from, n) copy_to_user(to, from, n) + +#define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n)) return retval; }) +#define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n)) return retval; }) + +/* + * Copy a null terminated string from userspace. + */ + +static inline long strncpy_from_user(char *dst, const char *src, + long count) +{ + char *tmp; + strncpy(dst, src, count); + for (tmp = dst; *tmp && count > 0; tmp++, count--); + return (tmp - dst); /* DAVIDM should we count a NUL ? check getname */ +} + +/* + * Return the size of a string (including the ending 0) + * + * Return 0 on exception, a value greater than N if too long + */ +static inline long strnlen_user(const char *src, long n) +{ + return (strlen(src) + 1); /* DAVIDM make safer */ +} + +#define strlen_user(str) strnlen_user(str, 32767) + +/* + * Zero Userspace + */ + +static inline unsigned long clear_user(void *to, unsigned long n) +{ + memset(to, 0, n); + return (0); +} + +#endif |