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-rw-r--r--arch/sh/include/asm/uaccess.h256
1 files changed, 256 insertions, 0 deletions
diff --git a/arch/sh/include/asm/uaccess.h b/arch/sh/include/asm/uaccess.h
new file mode 100644
index 00000000000..45c2c9b2993
--- /dev/null
+++ b/arch/sh/include/asm/uaccess.h
@@ -0,0 +1,256 @@
+#ifndef __ASM_SH_UACCESS_H
+#define __ASM_SH_UACCESS_H
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <asm/segment.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+#define __addr_ok(addr) \
+ ((unsigned long __force)(addr) < current_thread_info()->addr_limit.seg)
+
+/*
+ * __access_ok: Check if address with size is OK or not.
+ *
+ * Uhhuh, this needs 33-bit arithmetic. We have a carry..
+ *
+ * sum := addr + size; carry? --> flag = true;
+ * if (sum >= addr_limit) flag = true;
+ */
+#define __access_ok(addr, size) \
+ (__addr_ok((addr) + (size)))
+#define access_ok(type, addr, size) \
+ (__chk_user_ptr(addr), \
+ __access_ok((unsigned long __force)(addr), (size)))
+
+/*
+ * Uh, these should become the main single-value transfer routines ...
+ * They automatically use the right size if we just have the right
+ * pointer type ...
+ *
+ * As SuperH uses the same address space for kernel and user data, we
+ * can just do these as direct assignments.
+ *
+ * Careful to not
+ * (a) re-use the arguments for side effects (sizeof is ok)
+ * (b) require any knowledge of processes at this stage
+ */
+#define put_user(x,ptr) __put_user_check((x), (ptr), sizeof(*(ptr)))
+#define get_user(x,ptr) __get_user_check((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * The "__xxx" versions do not do address space checking, useful when
+ * doing multiple accesses to the same area (the user has to do the
+ * checks by hand with "access_ok()")
+ */
+#define __put_user(x,ptr) __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
+#define __get_user(x,ptr) __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
+
+struct __large_struct { unsigned long buf[100]; };
+#define __m(x) (*(struct __large_struct __user *)(x))
+
+#define __get_user_nocheck(x,ptr,size) \
+({ \
+ long __gu_err; \
+ unsigned long __gu_val; \
+ const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
+ __chk_user_ptr(ptr); \
+ __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
+ (x) = (__typeof__(*(ptr)))__gu_val; \
+ __gu_err; \
+})
+
+#define __get_user_check(x,ptr,size) \
+({ \
+ long __gu_err = -EFAULT; \
+ unsigned long __gu_val = 0; \
+ const __typeof__(*(ptr)) *__gu_addr = (ptr); \
+ if (likely(access_ok(VERIFY_READ, __gu_addr, (size)))) \
+ __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
+ (x) = (__typeof__(*(ptr)))__gu_val; \
+ __gu_err; \
+})
+
+#define __put_user_nocheck(x,ptr,size) \
+({ \
+ long __pu_err; \
+ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
+ __chk_user_ptr(ptr); \
+ __put_user_size((x), __pu_addr, (size), __pu_err); \
+ __pu_err; \
+})
+
+#define __put_user_check(x,ptr,size) \
+({ \
+ long __pu_err = -EFAULT; \
+ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
+ if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) \
+ __put_user_size((x), __pu_addr, (size), \
+ __pu_err); \
+ __pu_err; \
+})
+
+#ifdef CONFIG_SUPERH32
+# include "uaccess_32.h"
+#else
+# include "uaccess_64.h"
+#endif
+
+/* Generic arbitrary sized copy. */
+/* Return the number of bytes NOT copied */
+__kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n);
+
+static __always_inline unsigned long
+__copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+ return __copy_user(to, (__force void *)from, n);
+}
+
+static __always_inline unsigned long __must_check
+__copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ return __copy_user((__force void *)to, from, n);
+}
+
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
+/*
+ * Clear the area and return remaining number of bytes
+ * (on failure. Usually it's 0.)
+ */
+__kernel_size_t __clear_user(void *addr, __kernel_size_t size);
+
+#define clear_user(addr,n) \
+({ \
+ void __user * __cl_addr = (addr); \
+ unsigned long __cl_size = (n); \
+ \
+ if (__cl_size && access_ok(VERIFY_WRITE, \
+ ((unsigned long)(__cl_addr)), __cl_size)) \
+ __cl_size = __clear_user(__cl_addr, __cl_size); \
+ \
+ __cl_size; \
+})
+
+/**
+ * strncpy_from_user: - Copy a NUL terminated string from userspace.
+ * @dst: Destination address, in kernel space. This buffer must be at
+ * least @count bytes long.
+ * @src: Source address, in user space.
+ * @count: Maximum number of bytes to copy, including the trailing NUL.
+ *
+ * Copies a NUL-terminated string from userspace to kernel space.
+ *
+ * On success, returns the length of the string (not including the trailing
+ * NUL).
+ *
+ * If access to userspace fails, returns -EFAULT (some data may have been
+ * copied).
+ *
+ * If @count is smaller than the length of the string, copies @count bytes
+ * and returns @count.
+ */
+#define strncpy_from_user(dest,src,count) \
+({ \
+ unsigned long __sfu_src = (unsigned long)(src); \
+ int __sfu_count = (int)(count); \
+ long __sfu_res = -EFAULT; \
+ \
+ if (__access_ok(__sfu_src, __sfu_count)) \
+ __sfu_res = __strncpy_from_user((unsigned long)(dest), \
+ __sfu_src, __sfu_count); \
+ \
+ __sfu_res; \
+})
+
+static inline unsigned long
+copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+ unsigned long __copy_from = (unsigned long) from;
+ __kernel_size_t __copy_size = (__kernel_size_t) n;
+
+ if (__copy_size && __access_ok(__copy_from, __copy_size))
+ return __copy_user(to, from, __copy_size);
+
+ return __copy_size;
+}
+
+static inline unsigned long
+copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ unsigned long __copy_to = (unsigned long) to;
+ __kernel_size_t __copy_size = (__kernel_size_t) n;
+
+ if (__copy_size && __access_ok(__copy_to, __copy_size))
+ return __copy_user(to, from, __copy_size);
+
+ return __copy_size;
+}
+
+/**
+ * strnlen_user: - Get the size of a string in user space.
+ * @s: The string to measure.
+ * @n: The maximum valid length
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Get the size of a NUL-terminated string in user space.
+ *
+ * Returns the size of the string INCLUDING the terminating NUL.
+ * On exception, returns 0.
+ * If the string is too long, returns a value greater than @n.
+ */
+static inline long strnlen_user(const char __user *s, long n)
+{
+ if (!__addr_ok(s))
+ return 0;
+ else
+ return __strnlen_user(s, n);
+}
+
+/**
+ * strlen_user: - Get the size of a string in user space.
+ * @str: The string to measure.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Get the size of a NUL-terminated string in user space.
+ *
+ * Returns the size of the string INCLUDING the terminating NUL.
+ * On exception, returns 0.
+ *
+ * If there is a limit on the length of a valid string, you may wish to
+ * consider using strnlen_user() instead.
+ */
+#define strlen_user(str) strnlen_user(str, ~0UL >> 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;
+};
+
+#if defined(CONFIG_SUPERH64) && defined(CONFIG_MMU)
+#define ARCH_HAS_SEARCH_EXTABLE
+#endif
+
+int fixup_exception(struct pt_regs *regs);
+/* Returns 0 if exception not found and fixup.unit otherwise. */
+unsigned long search_exception_table(unsigned long addr);
+const struct exception_table_entry *search_exception_tables(unsigned long addr);
+
+
+#endif /* __ASM_SH_UACCESS_H */