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-rw-r--r--arch/m68knommu/include/asm/uaccess.h181
1 files changed, 181 insertions, 0 deletions
diff --git a/arch/m68knommu/include/asm/uaccess.h b/arch/m68knommu/include/asm/uaccess.h
new file mode 100644
index 0000000..68bbe9b
--- /dev/null
+++ b/arch/m68knommu/include/asm/uaccess.h
@@ -0,0 +1,181 @@
+#ifndef __M68KNOMMU_UACCESS_H
+#define __M68KNOMMU_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+
+#include <asm/segment.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+#define access_ok(type,addr,size) _access_ok((unsigned long)(addr),(size))
+
+/*
+ * It is not enough to just have access_ok check for a real RAM address.
+ * This would disallow the case of code/ro-data running XIP in flash/rom.
+ * Ideally we would check the possible flash ranges too, but that is
+ * currently not so easy.
+ */
+static inline int _access_ok(unsigned long addr, unsigned long size)
+{
+ return 1;
+}
+
+/*
+ * 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, l); \
+ break; \
+ case 8: \
+ memcpy(ptr, &__pu_val, sizeof (*(ptr))); \
+ break; \
+ default: \
+ __pu_err = __put_user_bad(); \
+ break; \
+ } \
+ __pu_err; \
+})
+#define __put_user(x, ptr) put_user(x, ptr)
+
+extern int __put_user_bad(void);
+
+/*
+ * 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,bwl) \
+ __asm__ ("move" #bwl " %0,%1" \
+ : /* no outputs */ \
+ :"d" (x),"m" (*__ptr(ptr)) : "memory")
+
+#define get_user(x, ptr) \
+({ \
+ int __gu_err = 0; \
+ typeof(x) __gu_val = 0; \
+ switch (sizeof(*(ptr))) { \
+ case 1: \
+ __get_user_asm(__gu_err, __gu_val, ptr, b, "=d"); \
+ break; \
+ case 2: \
+ __get_user_asm(__gu_err, __gu_val, ptr, w, "=r"); \
+ break; \
+ case 4: \
+ __get_user_asm(__gu_err, __gu_val, ptr, l, "=r"); \
+ break; \
+ case 8: \
+ memcpy((void *) &__gu_val, ptr, sizeof (*(ptr))); \
+ break; \
+ default: \
+ __gu_val = 0; \
+ __gu_err = __get_user_bad(); \
+ break; \
+ } \
+ (x) = (typeof(*(ptr))) __gu_val; \
+ __gu_err; \
+})
+#define __get_user(x, ptr) get_user(x, ptr)
+
+extern int __get_user_bad(void);
+
+#define __get_user_asm(err,x,ptr,bwl,reg) \
+ __asm__ ("move" #bwl " %1,%0" \
+ : "=d" (x) \
+ : "m" (*__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_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
+#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;
+}
+
+#define clear_user(to,n) __clear_user(to,n)
+
+#endif /* _M68KNOMMU_UACCESS_H */
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