file.h revision 277139
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 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#ifndef _LINUX_FILE_H_ 30#define _LINUX_FILE_H_ 31 32#include <sys/param.h> 33#include <sys/file.h> 34#include <sys/filedesc.h> 35#include <sys/refcount.h> 36#include <sys/proc.h> 37 38#include <linux/fs.h> 39 40struct linux_file; 41 42#undef file 43 44extern struct fileops linuxfileops; 45 46static inline struct linux_file * 47linux_fget(unsigned int fd) 48{ 49 struct file *file; 50 51 if (fget_unlocked(curthread->td_proc->p_fd, fd, NULL, 0, &file, 52 NULL) != 0) { 53 return (NULL); 54 } 55 return (struct linux_file *)file->f_data; 56} 57 58static inline void 59fput(struct linux_file *filp) 60{ 61 if (filp->_file == NULL) { 62 kfree(filp); 63 return; 64 } 65 if (refcount_release(&filp->_file->f_count)) { 66 _fdrop(filp->_file, curthread); 67 kfree(filp); 68 } 69} 70 71static inline void 72put_unused_fd(unsigned int fd) 73{ 74 struct file *file; 75 76 if (fget_unlocked(curthread->td_proc->p_fd, fd, NULL, 0, &file, 77 NULL) != 0) { 78 return; 79 } 80 /* 81 * NOTE: We should only get here when the "fd" has not been 82 * installed, so no need to free the associated Linux file 83 * structure. 84 */ 85 fdclose(curthread->td_proc->p_fd, file, fd, curthread); 86 87 /* drop extra reference */ 88 fdrop(file, curthread); 89} 90 91static inline void 92fd_install(unsigned int fd, struct linux_file *filp) 93{ 94 struct file *file; 95 96 if (fget_unlocked(curthread->td_proc->p_fd, fd, NULL, 0, &file, 97 NULL) != 0) { 98 file = NULL; 99 } 100 filp->_file = file; 101 finit(file, filp->f_mode, DTYPE_DEV, filp, &linuxfileops); 102 103 /* drop the extra reference */ 104 fput(filp); 105} 106 107static inline int 108get_unused_fd(void) 109{ 110 struct file *file; 111 int error; 112 int fd; 113 114 error = falloc(curthread, &file, &fd, 0); 115 if (error) 116 return -error; 117 /* drop the extra reference */ 118 fdrop(file, curthread); 119 return fd; 120} 121 122static inline struct linux_file * 123alloc_file(int mode, const struct file_operations *fops) 124{ 125 struct linux_file *filp; 126 127 filp = kzalloc(sizeof(*filp), GFP_KERNEL); 128 if (filp == NULL) 129 return (NULL); 130 filp->f_op = fops; 131 filp->f_mode = mode; 132 133 return filp; 134} 135 136struct fd { 137 struct linux_file *linux_file; 138}; 139 140static inline void fdput(struct fd fd) 141{ 142 fput(fd.linux_file); 143} 144 145static inline struct fd fdget(unsigned int fd) 146{ 147 struct linux_file *f = linux_fget(fd); 148 return (struct fd){f}; 149} 150 151#define file linux_file 152#define fget linux_fget 153 154#endif /* _LINUX_FILE_H_ */ 155