x86: merge common parts of uaccess. (ca233862) · Commits · git / linux-nf

include/asm-x86/uaccess.h

+124 −0

Original line number	Diff line number	Diff line
		#ifndef _ASM_UACCES_H_
		#define _ASM_UACCES_H_
		/*
		* User space memory access functions
		*/
		#include <linux/errno.h>
		#include <linux/compiler.h>
		#include <linux/thread_info.h>
		#include <linux/prefetch.h>
		#include <linux/string.h>
		#include <asm/asm.h>
		#include <asm/page.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_DS MAKE_MM_SEG(-1UL)
		#define USER_DS MAKE_MM_SEG(PAGE_OFFSET)

		#define get_ds() (KERNEL_DS)
		#define get_fs() (current_thread_info()->addr_limit)
		#define set_fs(x) (current_thread_info()->addr_limit = (x))

		#define segment_eq(a, b) ((a).seg == (b).seg)

		/*
		* Test whether a block of memory is a valid user space address.
		* Returns 0 if the range is valid, nonzero otherwise.
		*
		* This is equivalent to the following test:
		* (u33)addr + (u33)size >= (u33)current->addr_limit.seg (u65 for x86_64)
		*
		* This needs 33-bit (65-bit for x86_64) arithmetic. We have a carry...
		*/

		#define __range_not_ok(addr, size) \
		({ \
		unsigned long flag, roksum; \
		__chk_user_ptr(addr); \
		asm("add %3,%1 ; sbb %0,%0 ; cmp %1,%4 ; sbb $0,%0" \
		: "=&r" (flag), "=r" (roksum) \
		: "1" (addr), "g" ((long)(size)), \
		"rm" (current_thread_info()->addr_limit.seg)); \
		flag; \
		})

		/**
		* 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(type, addr, size) (likely(__range_not_ok(addr, size) == 0))

		/*
		* 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;
		};

		extern int fixup_exception(struct pt_regs *regs);

		/*
		* These are the main single-value transfer routines. They automatically
		* use the right size if we just have the right pointer type.
		*
		* This gets kind of ugly. We want to return _two_ values in "get_user()"
		* and yet we don't want to do any pointers, because that is too much
		* of a performance impact. Thus we have a few rather ugly macros here,
		* and hide all the ugliness from the user.
		*
		* The "__xxx" versions of the user access functions are versions that
		* do not verify the address space, that must have been done previously
		* with a separate "access_ok()" call (this is used when we do multiple
		* accesses to the same area of user memory).
		*/

		extern int __get_user_1(void);
		extern int __get_user_2(void);
		extern int __get_user_4(void);
		extern int __get_user_8(void);
		extern int __get_user_bad(void);

		#define __get_user_x(size, ret, x, ptr) \
		asm volatile("call __get_user_" #size \
		: "=a" (ret),"=d" (x) \
		: "0" (ptr)) \

		#ifdef CONFIG_X86_32
		# include "uaccess_32.h"
		#else
		# include "uaccess_64.h"
		#endif

		#endif

include/asm-x86/uaccess_32.h

+0 −110

Original line number	Diff line number	Diff line
		@@ -11,29 +11,6 @@
		#include <asm/asm.h>
		#include <asm/page.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_DS MAKE_MM_SEG(-1UL)
		#define USER_DS MAKE_MM_SEG(PAGE_OFFSET)

		#define get_ds() (KERNEL_DS)
		#define get_fs() (current_thread_info()->addr_limit)
		#define set_fs(x) (current_thread_info()->addr_limit = (x))

		#define segment_eq(a, b) ((a).seg == (b).seg)

		/*
		* movsl can be slow when source and dest are not both 8-byte aligned
		*/
		@@ -47,91 +24,6 @@ extern struct movsl_mask {
		((unsigned long __force)(addr) < \
		(current_thread_info()->addr_limit.seg))

		/*
		* Test whether a block of memory is a valid user space address.
		* Returns 0 if the range is valid, nonzero otherwise.
		*
		* This is equivalent to the following test:
		* (u33)addr + (u33)size >= (u33)current->addr_limit.seg
		*
		* This needs 33-bit arithmetic. We have a carry...
		*/
		#define __range_not_ok(addr, size) \
		({ \
		unsigned long flag, roksum; \
		__chk_user_ptr(addr); \
		asm("add %3,%1 ; sbb %0,%0; cmp %1,%4; sbb $0,%0" \
		:"=&r" (flag), "=r" (roksum) \
		:"1" (addr), "g" ((long)(size)), \
		"rm" (current_thread_info()->addr_limit.seg)); \
		flag; \
		})

		/**
		* 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(type, addr, size) (likely(__range_not_ok(addr, size) == 0))

		/*
		* 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;
		};

		extern int fixup_exception(struct pt_regs *regs);

		/*
		* These are the main single-value transfer routines. They automatically
		* use the right size if we just have the right pointer type.
		*
		* This gets kind of ugly. We want to return _two_ values in "get_user()"
		* and yet we don't want to do any pointers, because that is too much
		* of a performance impact. Thus we have a few rather ugly macros here,
		* and hide all the ugliness from the user.
		*
		* The "__xxx" versions of the user access functions are versions that
		* do not verify the address space, that must have been done previously
		* with a separate "access_ok()" call (this is used when we do multiple
		* accesses to the same area of user memory).
		*/

		extern void __get_user_1(void);
		extern void __get_user_2(void);
		extern void __get_user_4(void);

		#define __get_user_x(size, ret, x, ptr) \
		asm volatile("call __get_user_" #size \
		:"=a" (ret),"=d" (x) \
		:"0" (ptr))


		/* Careful: we have to cast the result to the type of the pointer
		* for sign reasons */

		@@ -386,8 +278,6 @@ struct __large_struct { unsigned long buf[100]; };
		__gu_err; \
		})

		extern long __get_user_bad(void);

		#define __get_user_size(x, ptr, size, retval, errret) \
		do { \
		retval = 0; \

include/asm-x86/uaccess_64.h

+0 −83

Original line number	Diff line number	Diff line
		@@ -9,88 +9,11 @@
		#include <linux/prefetch.h>
		#include <asm/page.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_DS MAKE_MM_SEG(-1UL)
		#define USER_DS MAKE_MM_SEG(PAGE_OFFSET)

		#define get_ds() (KERNEL_DS)
		#define get_fs() (current_thread_info()->addr_limit)
		#define set_fs(x) (current_thread_info()->addr_limit = (x))

		#define segment_eq(a, b) ((a).seg == (b).seg)

		#define __addr_ok(addr) (!((unsigned long)(addr) & \
		(current_thread_info()->addr_limit.seg)))

		/*
		* Uhhuh, this needs 65-bit arithmetic. We have a carry..
		*/
		#define __range_not_ok(addr, size) \
		({ \
		unsigned long flag, roksum; \
		__chk_user_ptr(addr); \
		asm("add %3,%1 ; sbb %0,%0 ; cmp %1,%4 ; sbb $0,%0" \
		: "=&r" (flag), "=r" (roksum) \
		: "1" (addr), "g" ((long)(size)), \
		"rm" (current_thread_info()->addr_limit.seg)); \
		flag; \
		})

		#define access_ok(type, addr, size) (likely(__range_not_ok(addr, size) == 0))

		/*
		* 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;
		};

		extern int fixup_exception(struct pt_regs *regs);

		#define ARCH_HAS_SEARCH_EXTABLE

		/*
		* These are the main single-value transfer routines. They automatically
		* use the right size if we just have the right pointer type.
		*
		* This gets kind of ugly. We want to return _two_ values in "get_user()"
		* and yet we don't want to do any pointers, because that is too much
		* of a performance impact. Thus we have a few rather ugly macros here,
		* and hide all the ugliness from the user.
		*
		* The "__xxx" versions of the user access functions are versions that
		* do not verify the address space, that must have been done previously
		* with a separate "access_ok()" call (this is used when we do multiple
		* accesses to the same area of user memory).
		*/

		#define __get_user_x(size, ret, x, ptr) \
		asm volatile("call __get_user_" #size \
		: "=a" (ret),"=d" (x) \
		: "0" (ptr)) \

		/* Careful: we have to cast the result to the type of the pointer
		* for sign reasons */

		@@ -226,12 +149,6 @@ struct __large_struct { unsigned long buf[100]; };
		__gu_err; \
		})

		extern int __get_user_1(void);
		extern int __get_user_2(void);
		extern int __get_user_4(void);
		extern int __get_user_8(void);
		extern int __get_user_bad(void);

		#define __get_user_size(x, ptr, size, retval) \
		do { \
		retval = 0; \