--- /dev/null
+/* MN10300 userspace access functions
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#ifndef _ASM_UACCESS_H
+#define _ASM_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/sched.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/errno.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) })
+
+#define KERNEL_XDS MAKE_MM_SEG(0xBFFFFFFF)
+#define KERNEL_DS MAKE_MM_SEG(0x9FFFFFFF)
+#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 __kernel_ds_p() (current_thread_info()->addr_limit.seg == 0x9FFFFFFF)
+
+#define segment_eq(a, b) ((a).seg == (b).seg)
+
+#define __addr_ok(addr) \
+ ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))
+
+/*
+ * check that a range of addresses falls within the current address limit
+ */
+static inline int ___range_ok(unsigned long addr, unsigned int size)
+{
+ int flag = 1, tmp;
+
+ asm(" add %3,%1 \n" /* set C-flag if addr + size > 4Gb */
+ " bcs 0f \n"
+ " cmp %4,%1 \n" /* jump if addr+size>limit (error) */
+ " bhi 0f \n"
+ " clr %0 \n" /* mark okay */
+ "0: \n"
+ : "=r"(flag), "=&r"(tmp)
+ : "1"(addr), "ir"(size),
+ "r"(current_thread_info()->addr_limit.seg), "0"(flag)
+ : "cc"
+ );
+
+ return flag;
+}
+
+#define __range_ok(addr, size) ___range_ok((unsigned long)(addr), (u32)(size))
+
+#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0)
+#define __access_ok(addr, size) (__range_ok((addr), (size)) == 0)
+
+static inline int verify_area(int type, const void *addr, unsigned long size)
+{
+ return access_ok(type, addr, size) ? 0 : -EFAULT;
+}
+
+
+/*
+ * 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 int fixup_exception(struct pt_regs *regs);
+
+#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)))
+
+/*
+ * The "xxx_ret" versions return constant specified in third argument, if
+ * something bad happens. These macros can be optimized for the
+ * case of just returning from the function xxx_ret is used.
+ */
+
+#define put_user_ret(x, ptr, ret) \
+ ({ if (put_user((x), (ptr))) return (ret); })
+#define get_user_ret(x, ptr, ret) \
+ ({ if (get_user((x), (ptr))) return (ret); })
+#define __put_user_ret(x, ptr, ret) \
+ ({ if (__put_user((x), (ptr))) return (ret); })
+#define __get_user_ret(x, ptr, ret) \
+ ({ if (__get_user((x), (ptr))) return (ret); })
+
+struct __large_struct { unsigned long buf[100]; };
+#define __m(x) (*(struct __large_struct *)(x))
+
+#define __get_user_nocheck(x, ptr, size) \
+({ \
+ __typeof(*(ptr)) __gu_val; \
+ unsigned long __gu_addr; \
+ int __gu_err; \
+ __gu_addr = (unsigned long) (ptr); \
+ switch (size) { \
+ case 1: __get_user_asm("bu"); break; \
+ case 2: __get_user_asm("hu"); break; \
+ case 4: __get_user_asm("" ); break; \
+ default: __get_user_unknown(); break; \
+ } \
+ x = (__typeof__(*(ptr))) __gu_val; \
+ __gu_err; \
+})
+
+#define __get_user_check(x, ptr, size) \
+({ \
+ __typeof__(*(ptr)) __gu_val; \
+ unsigned long __gu_addr; \
+ int __gu_err; \
+ __gu_addr = (unsigned long) (ptr); \
+ if (likely(__access_ok(__gu_addr,size))) { \
+ switch (size) { \
+ case 1: __get_user_asm("bu"); break; \
+ case 2: __get_user_asm("hu"); break; \
+ case 4: __get_user_asm("" ); break; \
+ default: __get_user_unknown(); break; \
+ } \
+ } \
+ else { \
+ __gu_err = -EFAULT; \
+ __gu_val = 0; \
+ } \
+ x = (__typeof__(*(ptr))) __gu_val; \
+ __gu_err; \
+})
+
+#define __get_user_asm(INSN) \
+({ \
+ asm volatile( \
+ "1:\n" \
+ " mov"INSN" %2,%1\n" \
+ " mov 0,%0\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ "3:\n\t" \
+ " mov %3,%0\n" \
+ " jmp 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .balign 4\n" \
+ " .long 1b, 3b\n" \
+ " .previous" \
+ : "=&r" (__gu_err), "=&r" (__gu_val) \
+ : "m" (__m(__gu_addr)), "i" (-EFAULT)); \
+})
+
+extern int __get_user_unknown(void);
+
+#define __put_user_nocheck(x, ptr, size) \
+({ \
+ union { \
+ __typeof__(*(ptr)) val; \
+ u32 bits[2]; \
+ } __pu_val; \
+ unsigned long __pu_addr; \
+ int __pu_err; \
+ __pu_val.val = (x); \
+ __pu_addr = (unsigned long) (ptr); \
+ switch (size) { \
+ case 1: __put_user_asm("bu"); break; \
+ case 2: __put_user_asm("hu"); break; \
+ case 4: __put_user_asm("" ); break; \
+ case 8: __put_user_asm8(); break; \
+ default: __pu_err = __put_user_unknown(); break; \
+ } \
+ __pu_err; \
+})
+
+#define __put_user_check(x, ptr, size) \
+({ \
+ union { \
+ __typeof__(*(ptr)) val; \
+ u32 bits[2]; \
+ } __pu_val; \
+ unsigned long __pu_addr; \
+ int __pu_err; \
+ __pu_val.val = (x); \
+ __pu_addr = (unsigned long) (ptr); \
+ if (likely(__access_ok(__pu_addr, size))) { \
+ switch (size) { \
+ case 1: __put_user_asm("bu"); break; \
+ case 2: __put_user_asm("hu"); break; \
+ case 4: __put_user_asm("" ); break; \
+ case 8: __put_user_asm8(); break; \
+ default: __pu_err = __put_user_unknown(); break; \
+ } \
+ } \
+ else { \
+ __pu_err = -EFAULT; \
+ } \
+ __pu_err; \
+})
+
+#define __put_user_asm(INSN) \
+({ \
+ asm volatile( \
+ "1:\n" \
+ " mov"INSN" %1,%2\n" \
+ " mov 0,%0\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ "3:\n" \
+ " mov %3,%0\n" \
+ " jmp 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .balign 4\n" \
+ " .long 1b, 3b\n" \
+ " .previous" \
+ : "=&r" (__pu_err) \
+ : "r" (__pu_val.val), "m" (__m(__pu_addr)), \
+ "i" (-EFAULT) \
+ ); \
+})
+
+#define __put_user_asm8() \
+({ \
+ asm volatile( \
+ "1: mov %1,%3 \n" \
+ "2: mov %2,%4 \n" \
+ " mov 0,%0 \n" \
+ "3: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "4: \n" \
+ " mov %5,%0 \n" \
+ " jmp 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\"\n" \
+ " .balign 4 \n" \
+ " .long 1b, 4b \n" \
+ " .long 2b, 4b \n" \
+ " .previous \n" \
+ : "=&r" (__pu_err) \
+ : "r" (__pu_val.bits[0]), "r" (__pu_val.bits[1]), \
+ "m" (__m(__pu_addr)), "m" (__m(__pu_addr+4)), \
+ "i" (-EFAULT) \
+ ); \
+})
+
+extern int __put_user_unknown(void);
+
+
+/*
+ * Copy To/From Userspace
+ */
+/* Generic arbitrary sized copy. */
+#define __copy_user(to, from, size) \
+do { \
+ if (size) { \
+ void *__to = to; \
+ const void *__from = from; \
+ int w; \
+ asm volatile( \
+ "0: movbu (%0),%3;\n" \
+ "1: movbu %3,(%1);\n" \
+ " inc %0;\n" \
+ " inc %1;\n" \
+ " add -1,%2;\n" \
+ " bne 0b;\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ "3: jmp 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .balign 4\n" \
+ " .long 0b,3b\n" \
+ " .long 1b,3b\n" \
+ " .previous\n" \
+ : "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\
+ : "0"(__from), "1"(__to), "2"(size) \
+ : "memory"); \
+ } \
+} while (0)
+
+#define __copy_user_zeroing(to, from, size) \
+do { \
+ if (size) { \
+ void *__to = to; \
+ const void *__from = from; \
+ int w; \
+ asm volatile( \
+ "0: movbu (%0),%3;\n" \
+ "1: movbu %3,(%1);\n" \
+ " inc %0;\n" \
+ " inc %1;\n" \
+ " add -1,%2;\n" \
+ " bne 0b;\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ "3:\n" \
+ " mov %2,%0\n" \
+ " clr %3\n" \
+ "4: movbu %3,(%1);\n" \
+ " inc %1;\n" \
+ " add -1,%2;\n" \
+ " bne 4b;\n" \
+ " mov %0,%2\n" \
+ " jmp 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .balign 4\n" \
+ " .long 0b,3b\n" \
+ " .long 1b,3b\n" \
+ " .previous\n" \
+ : "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\
+ : "0"(__from), "1"(__to), "2"(size) \
+ : "memory"); \
+ } \
+} while (0)
+
+/* 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 *from,
+ unsigned long n)
+{
+ __copy_user_zeroing(to, from, n);
+ return n;
+}
+
+static inline
+unsigned long __generic_copy_to_user_nocheck(void *to, const void *from,
+ unsigned long n)
+{
+ __copy_user(to, from, n);
+ return n;
+}
+
+
+#if 0
+#error don't use - these macros don't increment to & from pointers
+/* Optimize just a little bit when we know the size of the move. */
+#define __constant_copy_user(to, from, size) \
+do { \
+ asm volatile( \
+ " mov %0,a0;\n" \
+ "0: movbu (%1),d3;\n" \
+ "1: movbu d3,(%2);\n" \
+ " add -1,a0;\n" \
+ " bne 0b;\n" \
+ "2:;" \
+ ".section .fixup,\"ax\"\n" \
+ "3: jmp 2b\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ " .balign 4\n" \
+ " .long 0b,3b\n" \
+ " .long 1b,3b\n" \
+ ".previous" \
+ : \
+ : "d"(size), "d"(to), "d"(from) \
+ : "d3", "a0"); \
+} while (0)
+
+/* Optimize just a little bit when we know the size of the move. */
+#define __constant_copy_user_zeroing(to, from, size) \
+do { \
+ asm volatile( \
+ " mov %0,a0;\n" \
+ "0: movbu (%1),d3;\n" \
+ "1: movbu d3,(%2);\n" \
+ " add -1,a0;\n" \
+ " bne 0b;\n" \
+ "2:;" \
+ ".section .fixup,\"ax\"\n" \
+ "3: jmp 2b\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ " .balign 4\n" \
+ " .long 0b,3b\n" \
+ " .long 1b,3b\n" \
+ ".previous" \
+ : \
+ : "d"(size), "d"(to), "d"(from) \
+ : "d3", "a0"); \
+} while (0)
+
+static inline
+unsigned long __constant_copy_to_user(void *to, const void *from,
+ unsigned long n)
+{
+ if (access_ok(VERIFY_WRITE, to, n))
+ __constant_copy_user(to, from, n);
+ return n;
+}
+
+static inline
+unsigned long __constant_copy_from_user(void *to, const void *from,
+ unsigned long n)
+{
+ if (access_ok(VERIFY_READ, from, n))
+ __constant_copy_user_zeroing(to, from, n);
+ return n;
+}
+
+static inline
+unsigned long __constant_copy_to_user_nocheck(void *to, const void *from,
+ unsigned long n)
+{
+ __constant_copy_user(to, from, n);
+ return n;
+}
+
+static inline
+unsigned long __constant_copy_from_user_nocheck(void *to, const void *from,
+ unsigned long n)
+{
+ __constant_copy_user_zeroing(to, from, n);
+ return n;
+}
+#endif
+
+extern unsigned long __generic_copy_to_user(void __user *, const void *,
+ unsigned long);
+extern unsigned long __generic_copy_from_user(void *, const void __user *,
+ unsigned long);
+
+#define __copy_to_user_inatomic(to, from, n) \
+ __generic_copy_to_user_nocheck((to), (from), (n))
+#define __copy_from_user_inatomic(to, from, n) \
+ __generic_copy_from_user_nocheck((to), (from), (n))
+
+#define __copy_to_user(to, from, n) \
+({ \
+ might_sleep(); \
+ __copy_to_user_inatomic((to), (from), (n)); \
+})
+
+#define __copy_from_user(to, from, n) \
+({ \
+ might_sleep(); \
+ __copy_from_user_inatomic((to), (from), (n)); \
+})
+
+
+#define copy_to_user(to, from, n) __generic_copy_to_user((to), (from), (n))
+#define copy_from_user(to, from, n) __generic_copy_from_user((to), (from), (n))
+
+extern long strncpy_from_user(char *dst, const char __user *src, long count);
+extern long __strncpy_from_user(char *dst, const char __user *src, long count);
+extern long strnlen_user(const char __user *str, long n);
+#define strlen_user(str) strnlen_user(str, ~0UL >> 1)
+extern unsigned long clear_user(void __user *mem, unsigned long len);
+extern unsigned long __clear_user(void __user *mem, unsigned long len);
+
+#endif /* _ASM_UACCESS_H */
projects / cascardo / linux.git / blobdiff