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authorRussell King <rmk+kernel@arm.linux.org.uk>2009-09-24 21:22:33 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2009-09-24 21:22:33 +0100
commitbaea7b946f00a291b166ccae7fcfed6c01530cc6 (patch)
tree4aa275fbdbec9c7b9b4629e8bee2bbecd3c6a6af /arch/score/include/asm/uaccess.h
parentae19ffbadc1b2100285a5b5b3d0a4e0a11390904 (diff)
parent94e0fb086fc5663c38bbc0fe86d698be8314f82f (diff)
Merge branch 'origin' into for-linus
Conflicts: MAINTAINERS
Diffstat (limited to 'arch/score/include/asm/uaccess.h')
-rw-r--r--arch/score/include/asm/uaccess.h424
1 files changed, 424 insertions, 0 deletions
diff --git a/arch/score/include/asm/uaccess.h b/arch/score/include/asm/uaccess.h
new file mode 100644
index 00000000000..ab66ddde777
--- /dev/null
+++ b/arch/score/include/asm/uaccess.h
@@ -0,0 +1,424 @@
+#ifndef __SCORE_UACCESS_H
+#define __SCORE_UACCESS_H
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/thread_info.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+#define get_ds() (KERNEL_DS)
+#define get_fs() (current_thread_info()->addr_limit)
+#define segment_eq(a, b) ((a).seg == (b).seg)
+
+/*
+ * Is a address valid? This does a straighforward calculation rather
+ * than tests.
+ *
+ * Address valid if:
+ * - "addr" doesn't have any high-bits set
+ * - AND "size" doesn't have any high-bits set
+ * - AND "addr+size" doesn't have any high-bits set
+ * - OR we are in kernel mode.
+ *
+ * __ua_size() is a trick to avoid runtime checking of positive constant
+ * sizes; for those we already know at compile time that the size is ok.
+ */
+#define __ua_size(size) \
+ ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
+
+/*
+ * access_ok: - Checks if a user space pointer is valid
+ * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
+ * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
+ * to write to a block, it is always safe to read from it.
+ * @addr: User space pointer to start of block to check
+ * @size: Size of block to check
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Checks if a pointer to a block of memory in user space is valid.
+ *
+ * Returns true (nonzero) if the memory block may be valid, false (zero)
+ * if it is definitely invalid.
+ *
+ * Note that, depending on architecture, this function probably just
+ * checks that the pointer is in the user space range - after calling
+ * this function, memory access functions may still return -EFAULT.
+ */
+
+#define __access_ok(addr, size) \
+ (((long)((get_fs().seg) & \
+ ((addr) | ((addr) + (size)) | \
+ __ua_size(size)))) == 0)
+
+#define access_ok(type, addr, size) \
+ likely(__access_ok((unsigned long)(addr), (size)))
+
+/*
+ * put_user: - Write a simple value into user space.
+ * @x: Value to copy to user space.
+ * @ptr: Destination address, in user space.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * This macro copies a single simple value from kernel space to user
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and @x must be assignable
+ * to the result of dereferencing @ptr.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ */
+#define put_user(x, ptr) __put_user_check((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * get_user: - Get a simple variable from user space.
+ * @x: Variable to store result.
+ * @ptr: Source address, in user space.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * This macro copies a single simple variable from user space to kernel
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and the result of
+ * dereferencing @ptr must be assignable to @x without a cast.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ * On error, the variable @x is set to zero.
+ */
+#define get_user(x, ptr) __get_user_check((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * __put_user: - Write a simple value into user space, with less checking.
+ * @x: Value to copy to user space.
+ * @ptr: Destination address, in user space.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * This macro copies a single simple value from kernel space to user
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and @x must be assignable
+ * to the result of dereferencing @ptr.
+ *
+ * Caller must check the pointer with access_ok() before calling this
+ * function.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ */
+#define __put_user(x, ptr) __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * __get_user: - Get a simple variable from user space, with less checking.
+ * @x: Variable to store result.
+ * @ptr: Source address, in user space.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * This macro copies a single simple variable from user space to kernel
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and the result of
+ * dereferencing @ptr must be assignable to @x without a cast.
+ *
+ * Caller must check the pointer with access_ok() before calling this
+ * function.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ * On error, the variable @x is set to zero.
+ */
+#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))
+
+/*
+ * Yuck. We need two variants, one for 64bit operation and one
+ * for 32 bit mode and old iron.
+ */
+extern void __get_user_unknown(void);
+
+#define __get_user_common(val, size, ptr) \
+do { \
+ switch (size) { \
+ case 1: \
+ __get_user_asm(val, "lb", ptr); \
+ break; \
+ case 2: \
+ __get_user_asm(val, "lh", ptr); \
+ break; \
+ case 4: \
+ __get_user_asm(val, "lw", ptr); \
+ break; \
+ case 8: \
+ if ((copy_from_user((void *)&val, ptr, 8)) == 0) \
+ __gu_err = 0; \
+ else \
+ __gu_err = -EFAULT; \
+ break; \
+ default: \
+ __get_user_unknown(); \
+ break; \
+ } \
+} while (0)
+
+#define __get_user_nocheck(x, ptr, size) \
+({ \
+ long __gu_err = 0; \
+ __get_user_common((x), size, ptr); \
+ __gu_err; \
+})
+
+#define __get_user_check(x, ptr, size) \
+({ \
+ long __gu_err = -EFAULT; \
+ const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \
+ \
+ if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) \
+ __get_user_common((x), size, __gu_ptr); \
+ \
+ __gu_err; \
+})
+
+#define __get_user_asm(val, insn, addr) \
+{ \
+ long __gu_tmp; \
+ \
+ __asm__ __volatile__( \
+ "1:" insn " %1, %3\n" \
+ "2:\n" \
+ ".section .fixup,\"ax\"\n" \
+ "3:li %0, %4\n" \
+ "j 2b\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ ".word 1b, 3b\n" \
+ ".previous\n" \
+ : "=r" (__gu_err), "=r" (__gu_tmp) \
+ : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
+ \
+ (val) = (__typeof__(*(addr))) __gu_tmp; \
+}
+
+/*
+ * Yuck. We need two variants, one for 64bit operation and one
+ * for 32 bit mode and old iron.
+ */
+#define __put_user_nocheck(val, ptr, size) \
+({ \
+ __typeof__(*(ptr)) __pu_val; \
+ long __pu_err = 0; \
+ \
+ __pu_val = (val); \
+ switch (size) { \
+ case 1: \
+ __put_user_asm("sb", ptr); \
+ break; \
+ case 2: \
+ __put_user_asm("sh", ptr); \
+ break; \
+ case 4: \
+ __put_user_asm("sw", ptr); \
+ break; \
+ case 8: \
+ if ((__copy_to_user((void *)ptr, &__pu_val, 8)) == 0) \
+ __pu_err = 0; \
+ else \
+ __pu_err = -EFAULT; \
+ break; \
+ default: \
+ __put_user_unknown(); \
+ break; \
+ } \
+ __pu_err; \
+})
+
+
+#define __put_user_check(val, ptr, size) \
+({ \
+ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
+ __typeof__(*(ptr)) __pu_val = (val); \
+ long __pu_err = -EFAULT; \
+ \
+ if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
+ switch (size) { \
+ case 1: \
+ __put_user_asm("sb", __pu_addr); \
+ break; \
+ case 2: \
+ __put_user_asm("sh", __pu_addr); \
+ break; \
+ case 4: \
+ __put_user_asm("sw", __pu_addr); \
+ break; \
+ case 8: \
+ if ((__copy_to_user((void *)__pu_addr, &__pu_val, 8)) == 0)\
+ __pu_err = 0; \
+ else \
+ __pu_err = -EFAULT; \
+ break; \
+ default: \
+ __put_user_unknown(); \
+ break; \
+ } \
+ } \
+ __pu_err; \
+})
+
+#define __put_user_asm(insn, ptr) \
+ __asm__ __volatile__( \
+ "1:" insn " %2, %3\n" \
+ "2:\n" \
+ ".section .fixup,\"ax\"\n" \
+ "3:li %0, %4\n" \
+ "j 2b\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ ".word 1b, 3b\n" \
+ ".previous\n" \
+ : "=r" (__pu_err) \
+ : "0" (0), "r" (__pu_val), "o" (__m(ptr)), \
+ "i" (-EFAULT));
+
+extern void __put_user_unknown(void);
+extern int __copy_tofrom_user(void *to, const void *from, unsigned long len);
+
+static inline unsigned long
+copy_from_user(void *to, const void *from, unsigned long len)
+{
+ unsigned long over;
+
+ if (access_ok(VERIFY_READ, from, len))
+ return __copy_tofrom_user(to, from, len);
+
+ if ((unsigned long)from < TASK_SIZE) {
+ over = (unsigned long)from + len - TASK_SIZE;
+ return __copy_tofrom_user(to, from, len - over) + over;
+ }
+ return len;
+}
+
+static inline unsigned long
+copy_to_user(void *to, const void *from, unsigned long len)
+{
+ unsigned long over;
+
+ if (access_ok(VERIFY_WRITE, to, len))
+ return __copy_tofrom_user(to, from, len);
+
+ if ((unsigned long)to < TASK_SIZE) {
+ over = (unsigned long)to + len - TASK_SIZE;
+ return __copy_tofrom_user(to, from, len - over) + over;
+ }
+ return len;
+}
+
+#define __copy_from_user(to, from, len) \
+ __copy_tofrom_user((to), (from), (len))
+
+#define __copy_to_user(to, from, len) \
+ __copy_tofrom_user((to), (from), (len))
+
+static inline unsigned long
+__copy_to_user_inatomic(void *to, const void *from, unsigned long len)
+{
+ return __copy_to_user(to, from, len);
+}
+
+static inline unsigned long
+__copy_from_user_inatomic(void *to, const void *from, unsigned long len)
+{
+ return __copy_from_user(to, from, len);
+}
+
+#define __copy_in_user(to, from, len) __copy_from_user(to, from, len)
+
+static inline unsigned long
+copy_in_user(void *to, const void *from, unsigned long len)
+{
+ if (access_ok(VERIFY_READ, from, len) &&
+ access_ok(VERFITY_WRITE, to, len))
+ return copy_from_user(to, from, len);
+}
+
+/*
+ * __clear_user: - Zero a block of memory in user space, with less checking.
+ * @to: Destination address, in user space.
+ * @n: Number of bytes to zero.
+ *
+ * Zero a block of memory in user space. Caller must check
+ * the specified block with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+extern unsigned long __clear_user(void __user *src, unsigned long size);
+
+static inline unsigned long clear_user(char *src, unsigned long size)
+{
+ if (access_ok(VERIFY_WRITE, src, size))
+ return __clear_user(src, size);
+
+ return -EFAULT;
+}
+/*
+ * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
+ * @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.
+ * Caller must check the specified block with access_ok() before calling
+ * this function.
+ *
+ * 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.
+ */
+extern int __strncpy_from_user(char *dst, const char *src, long len);
+
+static inline int strncpy_from_user(char *dst, const char *src, long len)
+{
+ if (access_ok(VERIFY_READ, src, 1))
+ return __strncpy_from_user(dst, src, len);
+
+ return -EFAULT;
+}
+
+extern int __strlen_user(const char *src);
+static inline long strlen_user(const char __user *src)
+{
+ return __strlen_user(src);
+}
+
+extern int __strnlen_user(const char *str, long len);
+static inline long strnlen_user(const char __user *str, long len)
+{
+ if (!access_ok(VERIFY_READ, str, 0))
+ return 0;
+ else
+ return __strnlen_user(str, len);
+}
+
+struct exception_table_entry {
+ unsigned long insn;
+ unsigned long fixup;
+};
+
+extern int fixup_exception(struct pt_regs *regs);
+
+#endif /* __SCORE_UACCESS_H */
+