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+/*
+ * 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