/* * 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