1 files changed, 404 insertions, 0 deletions

diff --git a/arch/cris/include/asm/uaccess.h b/arch/cris/include/asm/uaccess.h
new file mode 100644
index 000000000000..914540801c5e
--- /dev/null
+++ b/arch/cris/include/asm/uaccess.h
@@ -0,0 +1,404 @@
+/* 
+ * Authors:    Bjorn Wesen (bjornw@axis.com)
+ *             Hans-Peter Nilsson (hp@axis.com)
+ */
+
+/* Asm:s have been tweaked (within the domain of correctness) to give
+   satisfactory results for "gcc version 2.96 20000427 (experimental)".
+
+   Check regularly...
+
+   Register $r9 is chosen for temporaries, being a call-clobbered register
+   first in line to be used (notably for local blocks), not colliding with
+   parameter registers.  */
+
+#ifndef _CRIS_UACCESS_H
+#define _CRIS_UACCESS_H
+
+#ifndef __ASSEMBLY__
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <asm/processor.h>
+#include <asm/page.h>
+
+#define VERIFY_READ     0
+#define VERIFY_WRITE    1
+
+/*
+ * The fs value determines whether argument validity checking should be
+ * performed or not.  If get_fs() == USER_DS, checking is performed, with
+ * get_fs() == KERNEL_DS, checking is bypassed.
+ *
+ * For historical reasons, these macros are grossly misnamed.
+ */
+
+#define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
+
+/* addr_limit is the maximum accessible address for the task. we misuse
+ * the KERNEL_DS and USER_DS values to both assign and compare the 
+ * addr_limit values through the equally misnamed get/set_fs macros.
+ * (see above)
+ */
+
+#define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFF)
+#define USER_DS         MAKE_MM_SEG(TASK_SIZE)
+
+#define get_ds()        (KERNEL_DS)
+#define get_fs()        (current_thread_info()->addr_limit)
+#define set_fs(x)       (current_thread_info()->addr_limit = (x))
+
+#define segment_eq(a,b) ((a).seg == (b).seg)
+
+#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))
+#define __user_ok(addr,size) (((size) <= TASK_SIZE)&&((addr) <= TASK_SIZE-(size)))
+#define __access_ok(addr,size) (__kernel_ok || __user_ok((addr),(size)))
+#define access_ok(type,addr,size) __access_ok((unsigned long)(addr),(size))
+
+#include <arch/uaccess.h>
+
+/*
+ * 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;
+};
+
+/*
+ * These are the main single-value transfer routines.  They automatically
+ * use the right size if we just have the right pointer type.
+ *
+ * This gets kind of ugly. We want to return _two_ values in "get_user()"
+ * and yet we don't want to do any pointers, because that is too much
+ * of a performance impact. Thus we have a few rather ugly macros here,
+ * and hide all the ugliness from the user.
+ *
+ * The "__xxx" versions of the user access functions are versions that
+ * do not verify the address space, that must have been done previously
+ * with a separate "access_ok()" call (this is used when we do multiple
+ * accesses to the same area of user memory).
+ *
+ * As we use the same address space for kernel and user data on
+ * CRIS, we can just do these as direct assignments.  (Of course, the
+ * exception handling means that it's no longer "just"...)
+ */
+#define get_user(x,ptr) \
+  __get_user_check((x),(ptr),sizeof(*(ptr)))
+#define put_user(x,ptr) \
+  __put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
+
+#define __get_user(x,ptr) \
+  __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
+#define __put_user(x,ptr) \
+  __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
+
+extern long __put_user_bad(void);
+
+#define __put_user_size(x,ptr,size,retval)                      \
+do {                                                            \
+        retval = 0;                                             \
+        switch (size) {                                         \
+          case 1: __put_user_asm(x,ptr,retval,"move.b"); break; \
+          case 2: __put_user_asm(x,ptr,retval,"move.w"); break; \
+          case 4: __put_user_asm(x,ptr,retval,"move.d"); break; \
+          case 8: __put_user_asm_64(x,ptr,retval); break;       \
+          default: __put_user_bad();                            \
+        }                                                       \
+} while (0)
+
+#define __get_user_size(x,ptr,size,retval)                      \
+do {                                                            \
+        retval = 0;                                             \
+        switch (size) {                                         \
+          case 1: __get_user_asm(x,ptr,retval,"move.b"); break; \
+          case 2: __get_user_asm(x,ptr,retval,"move.w"); break; \
+          case 4: __get_user_asm(x,ptr,retval,"move.d"); break; \
+          case 8: __get_user_asm_64(x,ptr,retval); break;       \
+          default: (x) = __get_user_bad();                      \
+        }                                                       \
+} while (0)
+
+#define __put_user_nocheck(x,ptr,size)                  \
+({                                                      \
+        long __pu_err;                                  \
+        __put_user_size((x),(ptr),(size),__pu_err);     \
+        __pu_err;                                       \
+})
+
+#define __put_user_check(x,ptr,size)                            \
+({                                                              \
+        long __pu_err = -EFAULT;                                \
+        __typeof__(*(ptr)) *__pu_addr = (ptr);                  \
+        if (access_ok(VERIFY_WRITE,__pu_addr,size))             \
+                __put_user_size((x),__pu_addr,(size),__pu_err); \
+        __pu_err;                                               \
+})
+
+struct __large_struct { unsigned long buf[100]; };
+#define __m(x) (*(struct __large_struct *)(x))
+
+
+
+#define __get_user_nocheck(x,ptr,size)                          \
+({                                                              \
+        long __gu_err, __gu_val;                                \
+        __get_user_size(__gu_val,(ptr),(size),__gu_err);        \
+        (x) = (__typeof__(*(ptr)))__gu_val;                     \
+        __gu_err;                                               \
+})
+
+#define __get_user_check(x,ptr,size)                                    \
+({                                                                      \
+        long __gu_err = -EFAULT, __gu_val = 0;                          \
+        const __typeof__(*(ptr)) *__gu_addr = (ptr);                    \
+        if (access_ok(VERIFY_READ,__gu_addr,size))                      \
+                __get_user_size(__gu_val,__gu_addr,(size),__gu_err);    \
+        (x) = (__typeof__(*(ptr)))__gu_val;                             \
+        __gu_err;                                                       \
+})
+
+extern long __get_user_bad(void);
+
+/* More complex functions.  Most are inline, but some call functions that
+   live in lib/usercopy.c  */
+
+extern unsigned long __copy_user(void __user *to, const void *from, unsigned long n);
+extern unsigned long __copy_user_zeroing(void *to, const void __user *from, unsigned long n);
+extern unsigned long __do_clear_user(void __user *to, unsigned long n);
+
+static inline unsigned long
+__generic_copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+        if (access_ok(VERIFY_WRITE, to, n))
+                return __copy_user(to,from,n);
+        return n;
+}
+
+static inline unsigned long
+__generic_copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+        if (access_ok(VERIFY_READ, from, n))
+                return __copy_user_zeroing(to,from,n);
+        return n;
+}
+
+static inline unsigned long
+__generic_clear_user(void __user *to, unsigned long n)
+{
+        if (access_ok(VERIFY_WRITE, to, n))
+                return __do_clear_user(to,n);
+        return n;
+}
+
+static inline long
+__strncpy_from_user(char *dst, const char __user *src, long count)
+{
+        return __do_strncpy_from_user(dst, src, count);
+}
+
+static inline long
+strncpy_from_user(char *dst, const char __user *src, long count)
+{
+        long res = -EFAULT;
+        if (access_ok(VERIFY_READ, src, 1))
+                res = __do_strncpy_from_user(dst, src, count);
+        return res;
+}
+
+
+/* Note that these expand awfully if made into switch constructs, so
+   don't do that.  */
+
+static inline unsigned long
+__constant_copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+        unsigned long ret = 0;
+        if (n == 0)
+                ;
+        else if (n == 1)
+                __asm_copy_from_user_1(to, from, ret);
+        else if (n == 2)
+                __asm_copy_from_user_2(to, from, ret);
+        else if (n == 3)
+                __asm_copy_from_user_3(to, from, ret);
+        else if (n == 4)
+                __asm_copy_from_user_4(to, from, ret);
+        else if (n == 5)
+                __asm_copy_from_user_5(to, from, ret);
+        else if (n == 6)
+                __asm_copy_from_user_6(to, from, ret);
+        else if (n == 7)
+                __asm_copy_from_user_7(to, from, ret);
+        else if (n == 8)
+                __asm_copy_from_user_8(to, from, ret);
+        else if (n == 9)
+                __asm_copy_from_user_9(to, from, ret);
+        else if (n == 10)
+                __asm_copy_from_user_10(to, from, ret);
+        else if (n == 11)
+                __asm_copy_from_user_11(to, from, ret);
+        else if (n == 12)
+                __asm_copy_from_user_12(to, from, ret);
+        else if (n == 13)
+                __asm_copy_from_user_13(to, from, ret);
+        else if (n == 14)
+                __asm_copy_from_user_14(to, from, ret);
+        else if (n == 15)
+                __asm_copy_from_user_15(to, from, ret);
+        else if (n == 16)
+                __asm_copy_from_user_16(to, from, ret);
+        else if (n == 20)
+                __asm_copy_from_user_20(to, from, ret);
+        else if (n == 24)
+                __asm_copy_from_user_24(to, from, ret);
+        else
+                ret = __generic_copy_from_user(to, from, n);
+
+        return ret;
+}
+
+/* Ditto, don't make a switch out of this.  */
+
+static inline unsigned long
+__constant_copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+        unsigned long ret = 0;
+        if (n == 0)
+                ;
+        else if (n == 1)
+                __asm_copy_to_user_1(to, from, ret);
+        else if (n == 2)
+                __asm_copy_to_user_2(to, from, ret);
+        else if (n == 3)
+                __asm_copy_to_user_3(to, from, ret);
+        else if (n == 4)
+                __asm_copy_to_user_4(to, from, ret);
+        else if (n == 5)
+                __asm_copy_to_user_5(to, from, ret);
+        else if (n == 6)
+                __asm_copy_to_user_6(to, from, ret);
+        else if (n == 7)
+                __asm_copy_to_user_7(to, from, ret);
+        else if (n == 8)
+                __asm_copy_to_user_8(to, from, ret);
+        else if (n == 9)
+                __asm_copy_to_user_9(to, from, ret);
+        else if (n == 10)
+                __asm_copy_to_user_10(to, from, ret);
+        else if (n == 11)
+                __asm_copy_to_user_11(to, from, ret);
+        else if (n == 12)
+                __asm_copy_to_user_12(to, from, ret);
+        else if (n == 13)
+                __asm_copy_to_user_13(to, from, ret);
+        else if (n == 14)
+                __asm_copy_to_user_14(to, from, ret);
+        else if (n == 15)
+                __asm_copy_to_user_15(to, from, ret);
+        else if (n == 16)
+                __asm_copy_to_user_16(to, from, ret);
+        else if (n == 20)
+                __asm_copy_to_user_20(to, from, ret);
+        else if (n == 24)
+                __asm_copy_to_user_24(to, from, ret);
+        else
+                ret = __generic_copy_to_user(to, from, n);
+
+        return ret;
+}
+
+/* No switch, please.  */
+
+static inline unsigned long
+__constant_clear_user(void __user *to, unsigned long n)
+{
+        unsigned long ret = 0;
+        if (n == 0)
+                ;
+        else if (n == 1)
+                __asm_clear_1(to, ret);
+        else if (n == 2)
+                __asm_clear_2(to, ret);
+        else if (n == 3)
+                __asm_clear_3(to, ret);
+        else if (n == 4)
+                __asm_clear_4(to, ret);
+        else if (n == 8)
+                __asm_clear_8(to, ret);
+        else if (n == 12)
+                __asm_clear_12(to, ret);
+        else if (n == 16)
+                __asm_clear_16(to, ret);
+        else if (n == 20)
+                __asm_clear_20(to, ret);
+        else if (n == 24)
+                __asm_clear_24(to, ret);
+        else
+                ret = __generic_clear_user(to, n);
+
+        return ret;
+}
+
+
+#define clear_user(to, n)                       \
+(__builtin_constant_p(n) ?                      \
+ __constant_clear_user(to, n) :                 \
+ __generic_clear_user(to, n))
+
+#define copy_from_user(to, from, n)             \
+(__builtin_constant_p(n) ?                      \
+ __constant_copy_from_user(to, from, n) :       \
+ __generic_copy_from_user(to, from, n))
+
+#define copy_to_user(to, from, n)               \
+(__builtin_constant_p(n) ?                      \
+ __constant_copy_to_user(to, from, n) :         \
+ __generic_copy_to_user(to, from, n))
+
+/* We let the __ versions of copy_from/to_user inline, because they're often
+ * used in fast paths and have only a small space overhead.
+ */
+
+static inline unsigned long
+__generic_copy_from_user_nocheck(void *to, const void __user *from,
+                                 unsigned long n)
+{
+        return __copy_user_zeroing(to,from,n);
+}
+
+static inline unsigned long
+__generic_copy_to_user_nocheck(void __user *to, const void *from,
+                               unsigned long n)
+{
+        return __copy_user(to,from,n);
+}
+
+static inline unsigned long
+__generic_clear_user_nocheck(void __user *to, unsigned long n)
+{
+        return __do_clear_user(to,n);
+}
+
+/* without checking */
+
+#define __copy_to_user(to,from,n)   __generic_copy_to_user_nocheck((to),(from),(n))
+#define __copy_from_user(to,from,n) __generic_copy_from_user_nocheck((to),(from),(n))
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+#define __clear_user(to,n) __generic_clear_user_nocheck((to),(n))
+
+#define strlen_user(str)        strnlen_user((str), 0x7ffffffe)
+
+#endif  /* __ASSEMBLY__ */
+
+#endif  /* _CRIS_UACCESS_H */