http://www.ousob.com --- Legacy Redefined OuSob - File: /wwwroot/clipx/usr/include/asm-i386/uaccess.h

#ifndef __i386_UACCESS_H #define __i386_UACCESS_H /* * User space memory access functions */ #include <linux/config.h> #include <linux/errno.h> #include <linux/thread_info.h> #include <linux/prefetch.h> #include <linux/string.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(0xFFFFFFFFUL) #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 */ #ifdef CONFIG_X86_INTEL_USERCOPY extern struct movsl_mask { int mask; } ____cacheline_aligned_in_smp movsl_mask; #endif #define __addr_ok(addr) ((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_ok(addr,size) ({ \ unsigned long flag,sum; \ __chk_user_ptr(addr); \ asm("addl %3,%1 ; sbbl %0,%0; cmpl %1,%4; sbbl $0,%0" \ :"=&r" (flag), "=r" (sum) \ :"1" (addr),"g" ((int)(size)),"g" (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_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 */ /** * 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) \ ({ int __ret_gu; \ unsigned long __val_gu; \ __chk_user_ptr(ptr); \ switch(sizeof (*(ptr))) { \ case 1: __get_user_x(1,__ret_gu,__val_gu,ptr); break; \ case 2: __get_user_x(2,__ret_gu,__val_gu,ptr); break; \ case 4: __get_user_x(4,__ret_gu,__val_gu,ptr); break; \ default: __get_user_x(X,__ret_gu,__val_gu,ptr); break; \ } \ (x) = (__typeof__(*(ptr)))__val_gu; \ __ret_gu; \ }) extern void __put_user_bad(void); /* * Strange magic calling convention: pointer in %ecx, * value in %eax(:%edx), return value in %eax, no clobbers. */ extern void __put_user_1(void); extern void __put_user_2(void); extern void __put_user_4(void); extern void __put_user_8(void); #define __put_user_1(x, ptr) __asm__ __volatile__("call __put_user_1":"=a" (__ret_pu):"0" ((typeof(*(ptr)))(x)), "c" (ptr)) #define __put_user_2(x, ptr) __asm__ __volatile__("call __put_user_2":"=a" (__ret_pu):"0" ((typeof(*(ptr)))(x)), "c" (ptr)) #define __put_user_4(x, ptr) __asm__ __volatile__("call __put_user_4":"=a" (__ret_pu):"0" ((typeof(*(ptr)))(x)), "c" (ptr)) #define __put_user_8(x, ptr) __asm__ __volatile__("call __put_user_8":"=a" (__ret_pu):"A" ((typeof(*(ptr)))(x)), "c" (ptr)) #define __put_user_X(x, ptr) __asm__ __volatile__("call __put_user_X":"=a" (__ret_pu):"c" (ptr)) /** * 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. */ #ifdef CONFIG_X86_WP_WORKS_OK #define put_user(x,ptr) \ ({ int __ret_pu; \ __chk_user_ptr(ptr); \ switch(sizeof(*(ptr))) { \ case 1: __put_user_1(x, ptr); break; \ case 2: __put_user_2(x, ptr); break; \ case 4: __put_user_4(x, ptr); break; \ case 8: __put_user_8(x, ptr); break; \ default:__put_user_X(x, ptr); break; \ } \ __ret_pu; \ }) #else #define put_user(x,ptr) \ ({ \ int __ret_pu; \ __typeof__(*(ptr)) __pus_tmp = x; \ __ret_pu=0; \ if(unlikely(__copy_to_user_ll(ptr, &__pus_tmp, \ sizeof(*(ptr))) != 0)) \ __ret_pu=-EFAULT; \ __ret_pu; \ }) #endif /** * __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 __put_user_nocheck(x,ptr,size) \ ({ \ long __pu_err; \ __put_user_size((x),(ptr),(size),__pu_err,-EFAULT); \ __pu_err; \ }) #define __put_user_u64(x, addr, err) \ __asm__ __volatile__( \ "1: movl %%eax,0(%2)\n" \ "2: movl %%edx,4(%2)\n" \ "3:\n" \ ".section .fixup,\"ax\"\n" \ "4: movl %3,%0\n" \ " jmp 3b\n" \ ".previous\n" \ ".section __ex_table,\"a\"\n" \ " .align 4\n" \ " .long 1b,4b\n" \ " .long 2b,4b\n" \ ".previous" \ : "=r"(err) \ : "A" (x), "r" (addr), "i"(-EFAULT), "0"(err)) #ifdef CONFIG_X86_WP_WORKS_OK #define __put_user_size(x,ptr,size,retval,errret) \ do { \ retval = 0; \ __chk_user_ptr(ptr); \ switch (size) { \ case 1: __put_user_asm(x,ptr,retval,"b","b","iq",errret);break; \ case 2: __put_user_asm(x,ptr,retval,"w","w","ir",errret);break; \ case 4: __put_user_asm(x,ptr,retval,"l","","ir",errret); break; \ case 8: __put_user_u64((__typeof__(*ptr))(x),ptr,retval); break;\ default: __put_user_bad(); \ } \ } while (0) #else #define __put_user_size(x,ptr,size,retval,errret) \ do { \ __typeof__(*(ptr)) __pus_tmp = x; \ retval = 0; \ \ if(unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0)) \ retval = errret; \ } while (0) #endif struct __large_struct { unsigned long buf[100]; }; #define __m(x) (*(struct __large_struct __user *)(x)) /* * Tell gcc we read from memory instead of writing: this is because * we do not write to any memory gcc knows about, so there are no * aliasing issues. */ #define __put_user_asm(x, addr, err, itype, rtype, ltype, errret) \ __asm__ __volatile__( \ "1: mov"itype" %"rtype"1,%2\n" \ "2:\n" \ ".section .fixup,\"ax\"\n" \ "3: movl %3,%0\n" \ " jmp 2b\n" \ ".previous\n" \ ".section __ex_table,\"a\"\n" \ " .align 4\n" \ " .long 1b,3b\n" \ ".previous" \ : "=r"(err) \ : ltype (x), "m"(__m(addr)), "i"(errret), "0"(err)) #define __get_user_nocheck(x,ptr,size) \ ({ \ long __gu_err; \ unsigned long __gu_val; \ __get_user_size(__gu_val,(ptr),(size),__gu_err,-EFAULT);\ (x) = (__typeof__(*(ptr)))__gu_val; \ __gu_err; \ }) extern long __get_user_bad(void); #define __get_user_size(x,ptr,size,retval,errret) \ do { \ retval = 0; \ __chk_user_ptr(ptr); \ switch (size) { \ case 1: __get_user_asm(x,ptr,retval,"b","b","=q",errret);break; \ case 2: __get_user_asm(x,ptr,retval,"w","w","=r",errret);break; \ case 4: __get_user_asm(x,ptr,retval,"l","","=r",errret);break; \ default: (x) = __get_user_bad(); \ } \ } while (0) #define __get_user_asm(x, addr, err, itype, rtype, ltype, errret) \ __asm__ __volatile__( \ "1: mov"itype" %2,%"rtype"1\n" \ "2:\n" \ ".section .fixup,\"ax\"\n" \ "3: movl %3,%0\n" \ " xor"itype" %"rtype"1,%"rtype"1\n" \ " jmp 2b\n" \ ".previous\n" \ ".section __ex_table,\"a\"\n" \ " .align 4\n" \ " .long 1b,3b\n" \ ".previous" \ : "=r"(err), ltype (x) \ : "m"(__m(addr)), "i"(errret), "0"(err)) unsigned long __must_check __copy_to_user_ll(void __user *to, const void *from, unsigned long n); unsigned long __must_check __copy_from_user_ll(void *to, const void __user *from, unsigned long n); /* * Here we special-case 1, 2 and 4-byte copy_*_user invocations. On a fault * we return the initial request size (1, 2 or 4), as copy_*_user should do. * If a store crosses a page boundary and gets a fault, the x86 will not write * anything, so this is accurate. */ /** * __copy_to_user: - Copy a block of data into user space, with less checking. * @to: Destination address, in user space. * @from: Source address, in kernel space. * @n: Number of bytes to copy. * * Context: User context only. This function may sleep. * * Copy data from kernel space to user space. Caller must check * the specified block with access_ok() before calling this function. * * Returns number of bytes that could not be copied. * On success, this will be zero. */ static __always_inline unsigned long __must_check __copy_to_user_inatomic(void __user *to, const void *from, unsigned long n) { if (__builtin_constant_p(n)) { unsigned long ret; switch (n) { case 1: __put_user_size(*(u8 *)from, (u8 __user *)to, 1, ret, 1); return ret; case 2: __put_user_size(*(u16 *)from, (u16 __user *)to, 2, ret, 2); return ret; case 4: __put_user_size(*(u32 *)from, (u32 __user *)to, 4, ret, 4); return ret; } } return __copy_to_user_ll(to, from, n); } static __always_inline unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n) { might_sleep(); return __copy_to_user_inatomic(to, from, n); } /** * __copy_from_user: - Copy a block of data from user space, with less checking. * @to: Destination address, in kernel space. * @from: Source address, in user space. * @n: Number of bytes to copy. * * Context: User context only. This function may sleep. * * Copy data from user space to kernel space. Caller must check * the specified block with access_ok() before calling this function. * * Returns number of bytes that could not be copied. * On success, this will be zero. * * If some data could not be copied, this function will pad the copied * data to the requested size using zero bytes. */ static __always_inline unsigned long __copy_from_user_inatomic(void *to, const void __user *from, unsigned long n) { if (__builtin_constant_p(n)) { unsigned long ret; switch (n) { case 1: __get_user_size(*(u8 *)to, from, 1, ret, 1); return ret; case 2: __get_user_size(*(u16 *)to, from, 2, ret, 2); return ret; case 4: __get_user_size(*(u32 *)to, from, 4, ret, 4); return ret; } } return __copy_from_user_ll(to, from, n); } static __always_inline unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n) { might_sleep(); return __copy_from_user_inatomic(to, from, n); } unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n); unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n); long __must_check strncpy_from_user(char *dst, const char __user *src, long count); long __must_check __strncpy_from_user(char *dst, const char __user *src, long count); /** * strlen_user: - Get the size of a string in user space. * @str: The string to measure. * * Context: User context only. This function may sleep. * * Get the size of a NUL-terminated string in user space. * * Returns the size of the string INCLUDING the terminating NUL. * On exception, returns 0. * * If there is a limit on the length of a valid string, you may wish to * consider using strnlen_user() instead. */ #define strlen_user(str) strnlen_user(str, ~0UL >> 1) long strnlen_user(const char __user *str, long n); unsigned long __must_check clear_user(void __user *mem, unsigned long len); unsigned long __must_check __clear_user(void __user *mem, unsigned long len); #endif /* __i386_UACCESS_H */