/*
+ * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2008-2009 PetaLogix
* Copyright (C) 2006 Atmark Techno, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
#include <asm/mmu.h>
#include <asm/page.h>
#include <asm/pgtable.h>
-#include <asm/segment.h>
#include <linux/string.h>
#define VERIFY_READ 0
#define VERIFY_WRITE 1
-extern int ___range_ok(unsigned long addr, unsigned long size);
+/*
+ * On Microblaze the fs value is actually the top of the corresponding
+ * address space.
+ *
+ * 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.
+ *
+ * For non-MMU arch like Microblaze, KERNEL_DS and USER_DS is equal.
+ */
+# define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
+
+# ifndef CONFIG_MMU
+# define KERNEL_DS MAKE_MM_SEG(0)
+# define USER_DS KERNEL_DS
+# else
+# define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF)
+# define USER_DS MAKE_MM_SEG(TASK_SIZE - 1)
+# endif
+
+# define get_ds() (KERNEL_DS)
+# define get_fs() (current_thread_info()->addr_limit)
+# define set_fs(val) (current_thread_info()->addr_limit = (val))
+
+# define segment_eq(a, b) ((a).seg == (b).seg)
+
+/*
+ * 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);
+
+#ifndef CONFIG_MMU
+
+/* Check against bounds of physical memory */
+static inline int ___range_ok(unsigned long addr, unsigned long size)
+{
+ return ((addr < memory_start) ||
+ ((addr + size) > memory_end));
+}
#define __range_ok(addr, size) \
___range_ok((unsigned long)(addr), (unsigned long)(size))
#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0)
-#define __access_ok(add, size) (__range_ok((addr), (size)) == 0)
-extern inline int bad_user_access_length(void)
+#else
+
+/*
+ * Address is valid if:
+ * - "addr", "addr + size" and "size" are all below the limit
+ */
+#define access_ok(type, addr, size) \
+ (get_fs().seg > (((unsigned long)(addr)) | \
+ (size) | ((unsigned long)(addr) + (size))))
+
+/* || printk("access_ok failed for %s at 0x%08lx (size %d), seg 0x%08x\n",
+ type?"WRITE":"READ",addr,size,get_fs().seg)) */
+
+#endif
+
+#ifdef CONFIG_MMU
+# define __FIXUP_SECTION ".section .fixup,\"ax\"\n"
+# define __EX_TABLE_SECTION ".section __ex_table,\"a\"\n"
+#else
+# define __FIXUP_SECTION ".section .discard,\"ax\"\n"
+# define __EX_TABLE_SECTION ".section .discard,\"a\"\n"
+#endif
+
+extern unsigned long __copy_tofrom_user(void __user *to,
+ const void __user *from, unsigned long size);
+
+/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */
+static inline unsigned long __must_check __clear_user(void __user *to,
+ unsigned long n)
{
- return 0;
+ /* normal memset with two words to __ex_table */
+ __asm__ __volatile__ ( \
+ "1: sb r0, %2, r0;" \
+ " addik %0, %0, -1;" \
+ " bneid %0, 1b;" \
+ " addik %2, %2, 1;" \
+ "2: " \
+ __EX_TABLE_SECTION \
+ ".word 1b,2b;" \
+ ".previous;" \
+ : "=r"(n) \
+ : "0"(n), "r"(to)
+ );
+ return n;
}
-/* FIXME this is function for optimalization -> memcpy */
-#define __get_user(var, ptr) \
- ({ \
- int __gu_err = 0; \
- switch (sizeof(*(ptr))) { \
- case 1: \
- case 2: \
- case 4: \
- (var) = *(ptr); \
- break; \
- case 8: \
- memcpy((void *) &(var), (ptr), 8); \
- break; \
- default: \
- (var) = 0; \
- __gu_err = __get_user_bad(); \
- break; \
- } \
- __gu_err; \
- })
-
-#define __get_user_bad() (bad_user_access_length(), (-EFAULT))
-
-#define __put_user(var, ptr) \
- ({ \
- int __pu_err = 0; \
- switch (sizeof(*(ptr))) { \
- case 1: \
- case 2: \
- case 4: \
- *(ptr) = (var); \
- break; \
- case 8: { \
- typeof(*(ptr)) __pu_val = var; \
- memcpy(ptr, &__pu_val, sizeof(__pu_val));\
- } \
- break; \
- default: \
- __pu_err = __put_user_bad(); \
- break; \
+
+static inline unsigned long __must_check clear_user(void __user *to,
+ unsigned long n)
+{
+ might_sleep();
+ if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
+ return n;
+
+ return __clear_user(to, n);
+}
+
+/* put_user and get_user macros */
+extern long __user_bad(void);
+
+#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
+({ \
+ __asm__ __volatile__ ( \
+ "1:" insn " %1, %2, r0;" \
+ " addk %0, r0, r0;" \
+ "2: " \
+ __FIXUP_SECTION \
+ "3: brid 2b;" \
+ " addik %0, r0, %3;" \
+ ".previous;" \
+ __EX_TABLE_SECTION \
+ ".word 1b,3b;" \
+ ".previous;" \
+ : "=&r"(__gu_err), "=r"(__gu_val) \
+ : "r"(__gu_ptr), "i"(-EFAULT) \
+ ); \
+})
+
+/**
+ * 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)))
+
+#define __get_user_check(x, ptr, size) \
+({ \
+ unsigned long __gu_val = 0; \
+ const typeof(*(ptr)) __user *__gu_addr = (ptr); \
+ int __gu_err = 0; \
+ \
+ if (access_ok(VERIFY_READ, __gu_addr, size)) { \
+ switch (size) { \
+ case 1: \
+ __get_user_asm("lbu", __gu_addr, __gu_val, \
+ __gu_err); \
+ break; \
+ case 2: \
+ __get_user_asm("lhu", __gu_addr, __gu_val, \
+ __gu_err); \
+ break; \
+ case 4: \
+ __get_user_asm("lw", __gu_addr, __gu_val, \
+ __gu_err); \
+ break; \
+ default: \
+ __gu_err = __user_bad(); \
+ break; \
} \
- __pu_err; \
- })
+ } else { \
+ __gu_err = -EFAULT; \
+ } \
+ x = (typeof(*(ptr)))__gu_val; \
+ __gu_err; \
+})
-#define __put_user_bad() (bad_user_access_length(), (-EFAULT))
+#define __get_user(x, ptr) \
+({ \
+ unsigned long __gu_val; \
+ /*unsigned long __gu_ptr = (unsigned long)(ptr);*/ \
+ long __gu_err; \
+ switch (sizeof(*(ptr))) { \
+ case 1: \
+ __get_user_asm("lbu", (ptr), __gu_val, __gu_err); \
+ break; \
+ case 2: \
+ __get_user_asm("lhu", (ptr), __gu_val, __gu_err); \
+ break; \
+ case 4: \
+ __get_user_asm("lw", (ptr), __gu_val, __gu_err); \
+ break; \
+ default: \
+ /* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\
+ } \
+ x = (__typeof__(*(ptr))) __gu_val; \
+ __gu_err; \
+})
-#define put_user(x, ptr) __put_user(x, ptr)
-#define get_user(x, ptr) __get_user(x, ptr)
-#define copy_to_user(to, from, n) (memcpy(to, from, n), 0)
-#define copy_from_user(to, from, n) (memcpy(to, from, n), 0)
+#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
+({ \
+ __asm__ __volatile__ ( \
+ "1:" insn " %1, %2, r0;" \
+ " addk %0, r0, r0;" \
+ "2: " \
+ __FIXUP_SECTION \
+ "3: brid 2b;" \
+ " addik %0, r0, %3;" \
+ ".previous;" \
+ __EX_TABLE_SECTION \
+ ".word 1b,3b;" \
+ ".previous;" \
+ : "=&r"(__gu_err) \
+ : "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \
+ ); \
+})
-#define __copy_to_user(to, from, n) (copy_to_user(to, from, n))
-#define __copy_from_user(to, from, n) (copy_from_user(to, from, n))
-#define __copy_to_user_inatomic(to, from, n) (__copy_to_user(to, from, n))
-#define __copy_from_user_inatomic(to, from, n) (__copy_from_user(to, from, n))
+#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err) \
+({ \
+ __asm__ __volatile__ (" lwi %0, %1, 0;" \
+ "1: swi %0, %2, 0;" \
+ " lwi %0, %1, 4;" \
+ "2: swi %0, %2, 4;" \
+ " addk %0, r0, r0;" \
+ "3: " \
+ __FIXUP_SECTION \
+ "4: brid 3b;" \
+ " addik %0, r0, %3;" \
+ ".previous;" \
+ __EX_TABLE_SECTION \
+ ".word 1b,4b,2b,4b;" \
+ ".previous;" \
+ : "=&r"(__gu_err) \
+ : "r"(&__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \
+ ); \
+})
-#define __clear_user(addr, n) (memset((void *)addr, 0, n), 0)
+/**
+ * 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)))
+
+#define __put_user_check(x, ptr, size) \
+({ \
+ typeof(*(ptr)) __pu_val; \
+ typeof(*(ptr)) __user *__pu_addr = (ptr); \
+ int __pu_err = 0; \
+ \
+ __pu_val = (x); \
+ if (access_ok(VERIFY_WRITE, __pu_addr, size)) { \
+ switch (size) { \
+ case 1: \
+ __put_user_asm("sb", __pu_addr, __pu_val, \
+ __pu_err); \
+ break; \
+ case 2: \
+ __put_user_asm("sh", __pu_addr, __pu_val, \
+ __pu_err); \
+ break; \
+ case 4: \
+ __put_user_asm("sw", __pu_addr, __pu_val, \
+ __pu_err); \
+ break; \
+ case 8: \
+ __put_user_asm_8(__pu_addr, __pu_val, __pu_err);\
+ break; \
+ default: \
+ __pu_err = __user_bad(); \
+ break; \
+ } \
+ } else { \
+ __pu_err = -EFAULT; \
+ } \
+ __pu_err; \
+})
+
+#define __put_user(x, ptr) \
+({ \
+ __typeof__(*(ptr)) volatile __gu_val = (x); \
+ long __gu_err = 0; \
+ switch (sizeof(__gu_val)) { \
+ case 1: \
+ __put_user_asm("sb", (ptr), __gu_val, __gu_err); \
+ break; \
+ case 2: \
+ __put_user_asm("sh", (ptr), __gu_val, __gu_err); \
+ break; \
+ case 4: \
+ __put_user_asm("sw", (ptr), __gu_val, __gu_err); \
+ break; \
+ case 8: \
+ __put_user_asm_8((ptr), __gu_val, __gu_err); \
+ break; \
+ default: \
+ /*__gu_err = -EINVAL;*/ __gu_err = __user_bad(); \
+ } \
+ __gu_err; \
+})
-static inline unsigned long clear_user(void *addr, unsigned long size)
+
+/* copy_to_from_user */
+#define __copy_from_user(to, from, n) \
+ __copy_tofrom_user((__force void __user *)(to), \
+ (void __user *)(from), (n))
+#define __copy_from_user_inatomic(to, from, n) \
+ copy_from_user((to), (from), (n))
+
+static inline long copy_from_user(void *to,
+ const void __user *from, unsigned long n)
{
- if (access_ok(VERIFY_WRITE, addr, size))
- size = __clear_user(addr, size);
- return size;
+ might_sleep();
+ if (access_ok(VERIFY_READ, from, n))
+ return __copy_from_user(to, from, n);
+ return n;
}
-/* Returns 0 if exception not found and fixup otherwise. */
-extern unsigned long search_exception_table(unsigned long);
+#define __copy_to_user(to, from, n) \
+ __copy_tofrom_user((void __user *)(to), \
+ (__force const void __user *)(from), (n))
+#define __copy_to_user_inatomic(to, from, n) copy_to_user((to), (from), (n))
+
+static inline long copy_to_user(void __user *to,
+ const void *from, unsigned long n)
+{
+ might_sleep();
+ if (access_ok(VERIFY_WRITE, to, n))
+ return __copy_to_user(to, from, n);
+ return n;
+}
+
+/*
+ * Copy a null terminated string from userspace.
+ */
+extern int __strncpy_user(char *to, const char __user *from, int len);
+#define __strncpy_from_user __strncpy_user
-extern long strncpy_from_user(char *dst, const char __user *src, long count);
-extern long strnlen_user(const char __user *src, long count);
-extern long __strncpy_from_user(char *dst, const char __user *src, long count);
+static inline long
+strncpy_from_user(char *dst, const char __user *src, long count)
+{
+ if (!access_ok(VERIFY_READ, src, 1))
+ return -EFAULT;
+ return __strncpy_from_user(dst, src, count);
+}
/*
- * 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.
+ * Return the size of a string (including the ending 0)
*
- * 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.
+ * Return 0 on exception, a value greater than N if too long
*/
-struct exception_table_entry {
- unsigned long insn, fixup;
-};
+extern int __strnlen_user(const char __user *sstr, int len);
+
+static inline long strnlen_user(const char __user *src, long n)
+{
+ if (!access_ok(VERIFY_READ, src, 1))
+ return 0;
+ return __strnlen_user(src, n);
+}
#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff