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Diffstat (limited to 'include/asm-i386/uaccess.h')
| -rw-r--r-- | include/asm-i386/uaccess.h | 590 |
1 files changed, 0 insertions, 590 deletions
diff --git a/include/asm-i386/uaccess.h b/include/asm-i386/uaccess.h deleted file mode 100644 index d2a4f7be9c2c..000000000000 --- a/include/asm-i386/uaccess.h +++ /dev/null @@ -1,590 +0,0 @@ -#ifndef __i386_UACCESS_H -#define __i386_UACCESS_H - -/* - * User space memory access functions - */ -#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,roksum; \ - __chk_user_ptr(addr); \ - asm("addl %3,%1 ; sbbl %0,%0; cmpl %1,%4; sbbl $0,%0" \ - :"=&r" (flag), "=r" (roksum) \ - :"1" (addr),"g" ((int)(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_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; \ - __typeof__(*(ptr)) __pu_val; \ - __chk_user_ptr(ptr); \ - __pu_val = x; \ - switch(sizeof(*(ptr))) { \ - case 1: __put_user_1(__pu_val, ptr); break; \ - case 2: __put_user_2(__pu_val, ptr); break; \ - case 4: __put_user_4(__pu_val, ptr); break; \ - case 8: __put_user_8(__pu_val, ptr); break; \ - default:__put_user_X(__pu_val, 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); -unsigned long __must_check __copy_from_user_ll_nozero(void *to, - const void __user *from, unsigned long n); -unsigned long __must_check __copy_from_user_ll_nocache(void *to, - const void __user *from, unsigned long n); -unsigned long __must_check __copy_from_user_ll_nocache_nozero(void *to, - const void __user *from, unsigned long n); - -/** - * __copy_to_user_inatomic: - 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. - * - * Copy data from kernel space to user space. Caller must check - * the specified block with access_ok() before calling this function. - * The caller should also make sure he pins the user space address - * so that the we don't result in page fault and sleep. - * - * 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. - */ - -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); -} - -/** - * __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(void __user *to, const void *from, unsigned long n) -{ - might_sleep(); - return __copy_to_user_inatomic(to, from, n); -} - -static __always_inline unsigned long -__copy_from_user_inatomic(void *to, const void __user *from, unsigned long n) -{ - /* Avoid zeroing the tail if the copy fails.. - * If 'n' is constant and 1, 2, or 4, we do still zero on a failure, - * but as the zeroing behaviour is only significant when n is not - * constant, that shouldn't be a problem. - */ - 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_nozero(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. - * - * An alternate version - __copy_from_user_inatomic() - may be called from - * atomic context and will fail rather than sleep. In this case the - * uncopied bytes will *NOT* be padded with zeros. See fs/filemap.h - * for explanation of why this is needed. - */ -static __always_inline unsigned long -__copy_from_user(void *to, const void __user *from, unsigned long n) -{ - might_sleep(); - 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); -} - -#define ARCH_HAS_NOCACHE_UACCESS - -static __always_inline unsigned long __copy_from_user_nocache(void *to, - const void __user *from, unsigned long n) -{ - might_sleep(); - 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_nocache(to, from, n); -} - -static __always_inline unsigned long -__copy_from_user_inatomic_nocache(void *to, const void __user *from, unsigned long n) -{ - return __copy_from_user_ll_nocache_nozero(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, LONG_MAX) - -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 */ |