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@@ -1,5 +1,453 @@
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+#ifndef _ASM_UACCES_H_
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+#define _ASM_UACCES_H_
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+/*
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+ * User space memory access functions
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+ */
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+#include <linux/errno.h>
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+#include <linux/compiler.h>
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+#include <linux/thread_info.h>
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+#include <linux/prefetch.h>
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+#include <linux/string.h>
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+#include <asm/asm.h>
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+#include <asm/page.h>
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+
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+#define VERIFY_READ 0
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+#define VERIFY_WRITE 1
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+
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+/*
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+ * The fs value determines whether argument validity checking should be
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+ * performed or not. If get_fs() == USER_DS, checking is performed, with
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+ * get_fs() == KERNEL_DS, checking is bypassed.
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+ *
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+ * For historical reasons, these macros are grossly misnamed.
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+ */
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+
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+#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
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+
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+#define KERNEL_DS MAKE_MM_SEG(-1UL)
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+#define USER_DS MAKE_MM_SEG(PAGE_OFFSET)
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+
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+#define get_ds() (KERNEL_DS)
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+#define get_fs() (current_thread_info()->addr_limit)
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+#define set_fs(x) (current_thread_info()->addr_limit = (x))
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+
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+#define segment_eq(a, b) ((a).seg == (b).seg)
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+
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+#define __addr_ok(addr) \
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+ ((unsigned long __force)(addr) < \
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+ (current_thread_info()->addr_limit.seg))
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+
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+/*
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+ * Test whether a block of memory is a valid user space address.
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+ * Returns 0 if the range is valid, nonzero otherwise.
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+ *
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+ * This is equivalent to the following test:
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+ * (u33)addr + (u33)size >= (u33)current->addr_limit.seg (u65 for x86_64)
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+ *
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+ * This needs 33-bit (65-bit for x86_64) arithmetic. We have a carry...
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+ */
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+
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+#define __range_not_ok(addr, size) \
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+({ \
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+ unsigned long flag, roksum; \
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+ __chk_user_ptr(addr); \
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+ asm("add %3,%1 ; sbb %0,%0 ; cmp %1,%4 ; sbb $0,%0" \
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+ : "=&r" (flag), "=r" (roksum) \
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+ : "1" (addr), "g" ((long)(size)), \
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+ "rm" (current_thread_info()->addr_limit.seg)); \
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+ flag; \
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+})
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+
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+/**
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+ * access_ok: - Checks if a user space pointer is valid
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+ * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
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+ * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
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+ * to write to a block, it is always safe to read from it.
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+ * @addr: User space pointer to start of block to check
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+ * @size: Size of block to check
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+ *
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+ * Context: User context only. This function may sleep.
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+ *
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+ * Checks if a pointer to a block of memory in user space is valid.
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+ *
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+ * Returns true (nonzero) if the memory block may be valid, false (zero)
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+ * if it is definitely invalid.
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+ *
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+ * Note that, depending on architecture, this function probably just
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+ * checks that the pointer is in the user space range - after calling
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+ * this function, memory access functions may still return -EFAULT.
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+ */
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+#define access_ok(type, addr, size) (likely(__range_not_ok(addr, size) == 0))
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+
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+/*
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+ * The exception table consists of pairs of addresses: the first is the
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+ * address of an instruction that is allowed to fault, and the second is
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+ * the address at which the program should continue. No registers are
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+ * modified, so it is entirely up to the continuation code to figure out
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+ * what to do.
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+ *
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+ * All the routines below use bits of fixup code that are out of line
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+ * with the main instruction path. This means when everything is well,
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+ * we don't even have to jump over them. Further, they do not intrude
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+ * on our cache or tlb entries.
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+ */
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+
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+struct exception_table_entry {
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+ unsigned long insn, fixup;
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+};
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+
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+extern int fixup_exception(struct pt_regs *regs);
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+
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+/*
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+ * These are the main single-value transfer routines. They automatically
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+ * use the right size if we just have the right pointer type.
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+ *
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+ * This gets kind of ugly. We want to return _two_ values in "get_user()"
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+ * and yet we don't want to do any pointers, because that is too much
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+ * of a performance impact. Thus we have a few rather ugly macros here,
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+ * and hide all the ugliness from the user.
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+ *
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+ * The "__xxx" versions of the user access functions are versions that
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+ * do not verify the address space, that must have been done previously
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+ * with a separate "access_ok()" call (this is used when we do multiple
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+ * accesses to the same area of user memory).
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+ */
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+
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+extern int __get_user_1(void);
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+extern int __get_user_2(void);
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+extern int __get_user_4(void);
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+extern int __get_user_8(void);
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+extern int __get_user_bad(void);
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+
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+#define __get_user_x(size, ret, x, ptr) \
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+ asm volatile("call __get_user_" #size \
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+ : "=a" (ret),"=d" (x) \
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+ : "0" (ptr)) \
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+
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+/* Careful: we have to cast the result to the type of the pointer
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+ * for sign reasons */
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+
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+/**
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+ * get_user: - Get a simple variable from user space.
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+ * @x: Variable to store result.
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+ * @ptr: Source address, in user space.
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+ *
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+ * Context: User context only. This function may sleep.
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+ *
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+ * This macro copies a single simple variable from user space to kernel
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+ * space. It supports simple types like char and int, but not larger
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+ * data types like structures or arrays.
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+ *
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+ * @ptr must have pointer-to-simple-variable type, and the result of
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+ * dereferencing @ptr must be assignable to @x without a cast.
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+ *
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+ * Returns zero on success, or -EFAULT on error.
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+ * On error, the variable @x is set to zero.
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+ */
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+#ifdef CONFIG_X86_32
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+#define __get_user_8(__ret_gu, __val_gu, ptr) \
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+ __get_user_x(X, __ret_gu, __val_gu, ptr)
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+#else
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+#define __get_user_8(__ret_gu, __val_gu, ptr) \
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+ __get_user_x(8, __ret_gu, __val_gu, ptr)
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+#endif
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+
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+#define get_user(x, ptr) \
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+({ \
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+ int __ret_gu; \
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+ unsigned long __val_gu; \
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+ __chk_user_ptr(ptr); \
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+ switch (sizeof(*(ptr))) { \
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+ case 1: \
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+ __get_user_x(1, __ret_gu, __val_gu, ptr); \
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+ break; \
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+ case 2: \
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+ __get_user_x(2, __ret_gu, __val_gu, ptr); \
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+ break; \
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+ case 4: \
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+ __get_user_x(4, __ret_gu, __val_gu, ptr); \
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+ break; \
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+ case 8: \
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+ __get_user_8(__ret_gu, __val_gu, ptr); \
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+ break; \
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+ default: \
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+ __get_user_x(X, __ret_gu, __val_gu, ptr); \
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+ break; \
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+ } \
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+ (x) = (__typeof__(*(ptr)))__val_gu; \
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+ __ret_gu; \
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+})
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+
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+#define __put_user_x(size, x, ptr, __ret_pu) \
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+ asm volatile("call __put_user_" #size : "=a" (__ret_pu) \
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+ :"0" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
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+
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+
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+
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+#ifdef CONFIG_X86_32
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+#define __put_user_u64(x, addr, err) \
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+ asm volatile("1: movl %%eax,0(%2)\n" \
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+ "2: movl %%edx,4(%2)\n" \
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+ "3:\n" \
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+ ".section .fixup,\"ax\"\n" \
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+ "4: movl %3,%0\n" \
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+ " jmp 3b\n" \
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+ ".previous\n" \
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+ _ASM_EXTABLE(1b, 4b) \
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+ _ASM_EXTABLE(2b, 4b) \
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+ : "=r" (err) \
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+ : "A" (x), "r" (addr), "i" (-EFAULT), "0" (err))
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+
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+#define __put_user_x8(x, ptr, __ret_pu) \
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+ asm volatile("call __put_user_8" : "=a" (__ret_pu) \
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+ : "A" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
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+#else
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+#define __put_user_u64(x, ptr, retval) \
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+ __put_user_asm(x, ptr, retval, "q", "", "Zr", -EFAULT)
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+#define __put_user_x8(x, ptr, __ret_pu) __put_user_x(8, x, ptr, __ret_pu)
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+#endif
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+
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+extern void __put_user_bad(void);
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+
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+/*
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+ * Strange magic calling convention: pointer in %ecx,
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+ * value in %eax(:%edx), return value in %eax. clobbers %rbx
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+ */
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+extern void __put_user_1(void);
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+extern void __put_user_2(void);
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+extern void __put_user_4(void);
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+extern void __put_user_8(void);
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+
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+#ifdef CONFIG_X86_WP_WORKS_OK
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+
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+/**
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+ * put_user: - Write a simple value into user space.
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+ * @x: Value to copy to user space.
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+ * @ptr: Destination address, in user space.
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+ *
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+ * Context: User context only. This function may sleep.
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+ *
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+ * This macro copies a single simple value from kernel space to user
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+ * space. It supports simple types like char and int, but not larger
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+ * data types like structures or arrays.
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+ *
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+ * @ptr must have pointer-to-simple-variable type, and @x must be assignable
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+ * to the result of dereferencing @ptr.
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+ *
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+ * Returns zero on success, or -EFAULT on error.
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+ */
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+#define put_user(x, ptr) \
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+({ \
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+ int __ret_pu; \
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+ __typeof__(*(ptr)) __pu_val; \
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+ __chk_user_ptr(ptr); \
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+ __pu_val = x; \
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+ switch (sizeof(*(ptr))) { \
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+ case 1: \
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+ __put_user_x(1, __pu_val, ptr, __ret_pu); \
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+ break; \
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+ case 2: \
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+ __put_user_x(2, __pu_val, ptr, __ret_pu); \
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+ break; \
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+ case 4: \
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+ __put_user_x(4, __pu_val, ptr, __ret_pu); \
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+ break; \
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+ case 8: \
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+ __put_user_x8(__pu_val, ptr, __ret_pu); \
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+ break; \
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+ default: \
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+ __put_user_x(X, __pu_val, ptr, __ret_pu); \
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+ break; \
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+ } \
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+ __ret_pu; \
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+})
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+
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+#define __put_user_size(x, ptr, size, retval, errret) \
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+do { \
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+ retval = 0; \
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+ __chk_user_ptr(ptr); \
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+ switch (size) { \
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+ case 1: \
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+ __put_user_asm(x, ptr, retval, "b", "b", "iq", errret); \
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+ break; \
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+ case 2: \
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+ __put_user_asm(x, ptr, retval, "w", "w", "ir", errret); \
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+ break; \
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+ case 4: \
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+ __put_user_asm(x, ptr, retval, "l", "k", "ir", errret);\
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+ break; \
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+ case 8: \
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+ __put_user_u64((__typeof__(*ptr))(x), ptr, retval); \
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+ break; \
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+ default: \
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+ __put_user_bad(); \
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+ } \
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+} while (0)
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+
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+#else
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+
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+#define __put_user_size(x, ptr, size, retval, errret) \
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+do { \
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+ __typeof__(*(ptr))__pus_tmp = x; \
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+ retval = 0; \
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+ \
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+ if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0)) \
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+ retval = errret; \
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+} while (0)
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+
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+#define put_user(x, ptr) \
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+({ \
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+ int __ret_pu; \
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+ __typeof__(*(ptr))__pus_tmp = x; \
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+ __ret_pu = 0; \
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+ if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, \
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+ sizeof(*(ptr))) != 0)) \
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+ __ret_pu = -EFAULT; \
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+ __ret_pu; \
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+})
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+#endif
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+
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+#ifdef CONFIG_X86_32
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+#define __get_user_asm_u64(x, ptr, retval, errret) (x) = __get_user_bad()
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+#else
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+#define __get_user_asm_u64(x, ptr, retval, errret) \
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+ __get_user_asm(x, ptr, retval, "q", "", "=r", errret)
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+#endif
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+
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+#define __get_user_size(x, ptr, size, retval, errret) \
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+do { \
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+ retval = 0; \
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+ __chk_user_ptr(ptr); \
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+ switch (size) { \
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+ case 1: \
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+ __get_user_asm(x, ptr, retval, "b", "b", "=q", errret); \
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+ break; \
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+ case 2: \
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+ __get_user_asm(x, ptr, retval, "w", "w", "=r", errret); \
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+ break; \
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+ case 4: \
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+ __get_user_asm(x, ptr, retval, "l", "k", "=r", errret); \
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+ break; \
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+ case 8: \
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+ __get_user_asm_u64(x, ptr, retval, errret); \
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+ break; \
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+ default: \
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+ (x) = __get_user_bad(); \
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+ } \
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+} while (0)
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+
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+#define __get_user_asm(x, addr, err, itype, rtype, ltype, errret) \
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+ asm volatile("1: mov"itype" %2,%"rtype"1\n" \
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+ "2:\n" \
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+ ".section .fixup,\"ax\"\n" \
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+ "3: mov %3,%0\n" \
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+ " xor"itype" %"rtype"1,%"rtype"1\n" \
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+ " jmp 2b\n" \
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+ ".previous\n" \
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+ _ASM_EXTABLE(1b, 3b) \
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+ : "=r" (err), ltype(x) \
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+ : "m" (__m(addr)), "i" (errret), "0" (err))
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+
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+#define __put_user_nocheck(x, ptr, size) \
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+({ \
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+ long __pu_err; \
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+ __put_user_size((x), (ptr), (size), __pu_err, -EFAULT); \
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+ __pu_err; \
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+})
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+
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+#define __get_user_nocheck(x, ptr, size) \
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+({ \
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+ long __gu_err; \
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+ unsigned long __gu_val; \
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+ __get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT); \
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+ (x) = (__force __typeof__(*(ptr)))__gu_val; \
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+ __gu_err; \
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+})
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+
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+/* FIXME: this hack is definitely wrong -AK */
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+struct __large_struct { unsigned long buf[100]; };
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+#define __m(x) (*(struct __large_struct __user *)(x))
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+
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+/*
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+ * Tell gcc we read from memory instead of writing: this is because
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+ * we do not write to any memory gcc knows about, so there are no
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+ * aliasing issues.
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+ */
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+#define __put_user_asm(x, addr, err, itype, rtype, ltype, errret) \
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+ asm volatile("1: mov"itype" %"rtype"1,%2\n" \
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+ "2:\n" \
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|
|
+ ".section .fixup,\"ax\"\n" \
|
|
|
+ "3: mov %3,%0\n" \
|
|
|
+ " jmp 2b\n" \
|
|
|
+ ".previous\n" \
|
|
|
+ _ASM_EXTABLE(1b, 3b) \
|
|
|
+ : "=r"(err) \
|
|
|
+ : ltype(x), "m" (__m(addr)), "i" (errret), "0" (err))
|
|
|
+/**
|
|
|
+ * __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)))
|
|
|
+/**
|
|
|
+ * __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((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
|
|
|
+
|
|
|
+#define __get_user_unaligned __get_user
|
|
|
+#define __put_user_unaligned __put_user
|
|
|
+
|
|
|
+/*
|
|
|
+ * movsl can be slow when source and dest are not both 8-byte aligned
|
|
|
+ */
|
|
|
+#ifdef CONFIG_X86_INTEL_USERCOPY
|
|
|
+extern struct movsl_mask {
|
|
|
+ int mask;
|
|
|
+} ____cacheline_aligned_in_smp movsl_mask;
|
|
|
+#endif
|
|
|
+
|
|
|
+#define ARCH_HAS_NOCACHE_UACCESS 1
|
|
|
+
|
|
|
#ifdef CONFIG_X86_32
|
|
|
# include "uaccess_32.h"
|
|
|
#else
|
|
|
+# define ARCH_HAS_SEARCH_EXTABLE
|
|
|
# include "uaccess_64.h"
|
|
|
#endif
|
|
|
+
|
|
|
+#endif
|