1 /*- 2 * Copyright (c) 2010 Isilon Systems, Inc. 3 * Copyright (c) 2010 iX Systems, Inc. 4 * Copyright (c) 2010 Panasas, Inc. 5 * Copyright (c) 2013-2016 Mellanox Technologies, Ltd. 6 * Copyright (c) 2015 François Tigeot 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice unmodified, this list of conditions, and the following 14 * disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef _LINUXKPI_LINUX_UACCESS_H_ 32 #define _LINUXKPI_LINUX_UACCESS_H_ 33 34 #include <sys/param.h> 35 #include <sys/lock.h> 36 #include <sys/proc.h> 37 38 #include <vm/vm.h> 39 #include <vm/vm_extern.h> 40 41 #include <linux/compiler.h> 42 43 #define VERIFY_READ VM_PROT_READ 44 #define VERIFY_WRITE VM_PROT_WRITE 45 46 #define __get_user(_x, _p) ({ \ 47 int __err; \ 48 __typeof(*(_p)) __x; \ 49 __err = linux_copyin((_p), &(__x), sizeof(*(_p))); \ 50 (_x) = __x; \ 51 __err; \ 52 }) 53 54 #define __put_user(_x, _p) ({ \ 55 __typeof(*(_p)) __x = (_x); \ 56 linux_copyout(&(__x), (_p), sizeof(*(_p))); \ 57 }) 58 #define get_user(_x, _p) linux_copyin((_p), &(_x), sizeof(*(_p))) 59 #define put_user(_x, _p) __put_user(_x, _p) 60 #define clear_user(...) linux_clear_user(__VA_ARGS__) 61 62 #define access_ok(a,b) linux_access_ok(a,b) 63 64 extern int linux_copyin(const void *uaddr, void *kaddr, size_t len); 65 extern int linux_copyout(const void *kaddr, void *uaddr, size_t len); 66 extern size_t linux_clear_user(void *uaddr, size_t len); 67 extern int linux_access_ok(const void *uaddr, size_t len); 68 69 /* 70 * NOTE: Each pagefault_disable() call must have a corresponding 71 * pagefault_enable() call in the same scope. The former creates a new 72 * block and defines a temporary variable, and the latter uses the 73 * temporary variable and closes the block. Failure to balance the 74 * calls will result in a compile-time error. 75 */ 76 #define pagefault_disable(void) do { \ 77 int __saved_pflags = \ 78 vm_fault_disable_pagefaults() 79 80 #define pagefault_enable(void) \ 81 vm_fault_enable_pagefaults(__saved_pflags); \ 82 } while (0) 83 84 static inline bool 85 pagefault_disabled(void) 86 { 87 return ((curthread->td_pflags & TDP_NOFAULTING) != 0); 88 } 89 90 static inline int 91 __copy_to_user_inatomic(void __user *to, const void *from, unsigned n) 92 { 93 94 return (copyout_nofault(from, to, n) != 0 ? n : 0); 95 } 96 #define __copy_to_user_inatomic_nocache(to, from, n) \ 97 __copy_to_user_inatomic((to), (from), (n)) 98 99 static inline unsigned long 100 __copy_from_user_inatomic(void *to, const void __user *from, 101 unsigned long n) 102 { 103 /* 104 * XXXKIB. Equivalent Linux function is implemented using 105 * MOVNTI for aligned moves. For unaligned head and tail, 106 * normal move is performed. As such, it is not incorrect, if 107 * only somewhat slower, to use normal copyin. All uses 108 * except shmem_pwrite_fast() have the destination mapped WC. 109 */ 110 return ((copyin_nofault(__DECONST(void *, from), to, n) != 0 ? n : 0)); 111 } 112 #define __copy_from_user_inatomic_nocache(to, from, n) \ 113 __copy_from_user_inatomic((to), (from), (n)) 114 115 #endif /* _LINUXKPI_LINUX_UACCESS_H_ */ 116