1 /*- 2 * Copyright (c) 2010 Isilon Systems, Inc. 3 * Copyright (c) 2010 iX Systems, Inc. 4 * Copyright (c) 2010 Panasas, Inc. 5 * Copyright (c) 2013-2017 Mellanox Technologies, Ltd. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice unmodified, this list of conditions, and the following 13 * disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 #ifndef _LINUX_FILE_H_ 32 #define _LINUX_FILE_H_ 33 34 #include <sys/param.h> 35 #include <sys/file.h> 36 #include <sys/filedesc.h> 37 #include <sys/refcount.h> 38 #include <sys/capsicum.h> 39 #include <sys/proc.h> 40 41 #include <linux/fs.h> 42 #include <linux/slab.h> 43 44 struct linux_file; 45 46 #undef file 47 48 extern struct fileops linuxfileops; 49 50 static inline struct linux_file * 51 linux_fget(unsigned int fd) 52 { 53 cap_rights_t rights; 54 struct file *file; 55 56 if (fget_unlocked(curthread->td_proc->p_fd, fd, 57 cap_rights_init(&rights), &file, NULL) != 0) { 58 return (NULL); 59 } 60 return (struct linux_file *)file->f_data; 61 } 62 63 extern void linux_file_free(struct linux_file *filp); 64 65 static inline void 66 fput(struct linux_file *filp) 67 { 68 if (refcount_release(filp->_file == NULL ? 69 &filp->f_count : &filp->_file->f_count)) { 70 linux_file_free(filp); 71 } 72 } 73 74 static inline unsigned int 75 file_count(struct linux_file *filp) 76 { 77 return (filp->_file == NULL ? 78 filp->f_count : filp->_file->f_count); 79 } 80 81 static inline void 82 put_unused_fd(unsigned int fd) 83 { 84 cap_rights_t rights; 85 struct file *file; 86 87 if (fget_unlocked(curthread->td_proc->p_fd, fd, 88 cap_rights_init(&rights), &file, NULL) != 0) { 89 return; 90 } 91 /* 92 * NOTE: We should only get here when the "fd" has not been 93 * installed, so no need to free the associated Linux file 94 * structure. 95 */ 96 fdclose(curthread, file, fd); 97 98 /* drop extra reference */ 99 fdrop(file, curthread); 100 } 101 102 static inline void 103 fd_install(unsigned int fd, struct linux_file *filp) 104 { 105 cap_rights_t rights; 106 struct file *file; 107 108 if (fget_unlocked(curthread->td_proc->p_fd, fd, 109 cap_rights_init(&rights), &file, NULL) != 0) { 110 filp->_file = NULL; 111 } else { 112 filp->_file = file; 113 finit(file, filp->f_mode, DTYPE_DEV, filp, &linuxfileops); 114 115 /* transfer reference count from "filp" to "file" */ 116 while (refcount_release(&filp->f_count) == 0) 117 refcount_acquire(&file->f_count); 118 } 119 120 /* drop the extra reference */ 121 fput(filp); 122 } 123 124 static inline int 125 get_unused_fd(void) 126 { 127 struct file *file; 128 int error; 129 int fd; 130 131 error = falloc(curthread, &file, &fd, 0); 132 if (error) 133 return -error; 134 /* drop the extra reference */ 135 fdrop(file, curthread); 136 return fd; 137 } 138 139 static inline int 140 get_unused_fd_flags(int flags) 141 { 142 struct file *file; 143 int error; 144 int fd; 145 146 error = falloc(curthread, &file, &fd, flags); 147 if (error) 148 return -error; 149 /* drop the extra reference */ 150 fdrop(file, curthread); 151 return fd; 152 } 153 154 extern struct linux_file *linux_file_alloc(void); 155 156 static inline struct linux_file * 157 alloc_file(int mode, const struct file_operations *fops) 158 { 159 struct linux_file *filp; 160 161 filp = linux_file_alloc(); 162 filp->f_op = fops; 163 filp->f_mode = mode; 164 165 return (filp); 166 } 167 168 struct fd { 169 struct linux_file *linux_file; 170 }; 171 172 static inline void fdput(struct fd fd) 173 { 174 fput(fd.linux_file); 175 } 176 177 static inline struct fd fdget(unsigned int fd) 178 { 179 struct linux_file *f = linux_fget(fd); 180 return (struct fd){f}; 181 } 182 183 #define file linux_file 184 #define fget(...) linux_fget(__VA_ARGS__) 185 186 #endif /* _LINUX_FILE_H_ */ 187