| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138 | #ifndef _ASM_IA64_UACCESS_H#define _ASM_IA64_UACCESS_H/* * This file defines various macros to transfer memory areas across * the user/kernel boundary.  This needs to be done carefully because * this code is executed in kernel mode and uses user-specified * addresses.  Thus, we need to be careful not to let the user to * trick us into accessing kernel memory that would normally be * inaccessible.  This code is also fairly performance sensitive, * so we want to spend as little time doing safety checks as * possible. * * To make matters a bit more interesting, these macros sometimes also * called from within the kernel itself, in which case the address * validity check must be skipped.  The get_fs() macro tells us what * to do: if get_fs()==USER_DS, checking is performed, if * get_fs()==KERNEL_DS, checking is bypassed. * * Note that even if the memory area specified by the user is in a * valid address range, it is still possible that we'll get a page * fault while accessing it.  This is handled by filling out an * exception handler fixup entry for each instruction that has the * potential to fault.  When such a fault occurs, the page fault * handler checks to see whether the faulting instruction has a fixup * associated and, if so, sets r8 to -EFAULT and clears r9 to 0 and * then resumes execution at the continuation point. * * Based on <asm-alpha/uaccess.h>. * * Copyright (C) 1998, 1999, 2001-2004 Hewlett-Packard Co *	David Mosberger-Tang <davidm@hpl.hp.com> */#include <linux/compiler.h>#include <linux/errno.h>#include <linux/sched.h>#include <linux/page-flags.h>#include <linux/mm.h>#include <asm/intrinsics.h>#include <asm/pgtable.h>#include <asm/io.h>/* * For historical reasons, the following macros are grossly misnamed: */#define KERNEL_DS	((mm_segment_t) { ~0UL })		/* cf. access_ok() */#define USER_DS		((mm_segment_t) { TASK_SIZE-1 })	/* cf. access_ok() */#define VERIFY_READ	0#define VERIFY_WRITE	1#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)/* * When accessing user memory, we need to make sure the entire area really is in * user-level space.  In order to do this efficiently, we make sure that the page at * address TASK_SIZE is never valid.  We also need to make sure that the address doesn't * point inside the virtually mapped linear page table. */#define __access_ok(addr, size, segment)						\({											\	__chk_user_ptr(addr);								\	(likely((unsigned long) (addr) <= (segment).seg)				\	 && ((segment).seg == KERNEL_DS.seg						\	     || likely(REGION_OFFSET((unsigned long) (addr)) < RGN_MAP_LIMIT)));	\})#define access_ok(type, addr, size)	__access_ok((addr), (size), get_fs())/* * These are the main single-value transfer routines.  They automatically * use the right size if we just have the right pointer type. * * Careful to not * (a) re-use the arguments for side effects (sizeof/typeof is ok) * (b) require any knowledge of processes at this stage */#define put_user(x, ptr)	__put_user_check((__typeof__(*(ptr))) (x), (ptr), sizeof(*(ptr)), get_fs())#define get_user(x, ptr)	__get_user_check((x), (ptr), sizeof(*(ptr)), get_fs())/* * The "__xxx" versions do not do address space checking, useful when * doing multiple accesses to the same area (the programmer has to do the * checks by hand with "access_ok()") */#define __put_user(x, ptr)	__put_user_nocheck((__typeof__(*(ptr))) (x), (ptr), sizeof(*(ptr)))#define __get_user(x, ptr)	__get_user_nocheck((x), (ptr), sizeof(*(ptr)))extern long __put_user_unaligned_unknown (void);#define __put_user_unaligned(x, ptr)								\({												\	long __ret;										\	switch (sizeof(*(ptr))) {								\		case 1: __ret = __put_user((x), (ptr)); break;					\		case 2: __ret = (__put_user((x), (u8 __user *)(ptr)))				\			| (__put_user((x) >> 8, ((u8 __user *)(ptr) + 1))); break;		\		case 4: __ret = (__put_user((x), (u16 __user *)(ptr)))				\			| (__put_user((x) >> 16, ((u16 __user *)(ptr) + 1))); break;		\		case 8: __ret = (__put_user((x), (u32 __user *)(ptr)))				\			| (__put_user((x) >> 32, ((u32 __user *)(ptr) + 1))); break;		\		default: __ret = __put_user_unaligned_unknown();				\	}											\	__ret;											\})extern long __get_user_unaligned_unknown (void);#define __get_user_unaligned(x, ptr)								\({												\	long __ret;										\	switch (sizeof(*(ptr))) {								\		case 1: __ret = __get_user((x), (ptr)); break;					\		case 2: __ret = (__get_user((x), (u8 __user *)(ptr)))				\			| (__get_user((x) >> 8, ((u8 __user *)(ptr) + 1))); break;		\		case 4: __ret = (__get_user((x), (u16 __user *)(ptr)))				\			| (__get_user((x) >> 16, ((u16 __user *)(ptr) + 1))); break;		\		case 8: __ret = (__get_user((x), (u32 __user *)(ptr)))				\			| (__get_user((x) >> 32, ((u32 __user *)(ptr) + 1))); break;		\		default: __ret = __get_user_unaligned_unknown();				\	}											\	__ret;											\})#ifdef ASM_SUPPORTED  struct __large_struct { unsigned long buf[100]; };# define __m(x) (*(struct __large_struct __user *)(x))/* We need to declare the __ex_table section before we can use it in .xdata.  */asm (".section \"__ex_table\", \"a\"\n\t.previous");# define __get_user_size(val, addr, n, err)							\do {												\
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