file.h revision 255240 
1/*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice unmodified, this list of conditions, and the following
12 *    disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28#ifndef	_LINUX_FILE_H_
29#define	_LINUX_FILE_H_
30
31#include <sys/param.h>
32#include <sys/file.h>
33#include <sys/filedesc.h>
34#include <sys/refcount.h>
35#include <sys/proc.h>
36
37#include <linux/fs.h>
38
39struct linux_file;
40
41#undef file
42
43extern struct fileops linuxfileops;
44
45static inline struct linux_file *
46linux_fget(unsigned int fd)
47{
48	struct file *file;
49
50	if (fget_unlocked(curthread->td_proc->p_fd, fd, NULL, 0, &file,
51	    NULL) != 0) {
52		return (NULL);
53	}
54	return (struct linux_file *)file->f_data;
55}
56
57static inline void
58fput(struct linux_file *filp)
59{
60	if (filp->_file == NULL) {
61		kfree(filp);
62		return;
63	}
64	if (refcount_release(&filp->_file->f_count)) {
65		_fdrop(filp->_file, curthread);
66		kfree(filp);
67	}
68}
69
70static inline void
71put_unused_fd(unsigned int fd)
72{
73	struct file *file;
74
75	if (fget_unlocked(curthread->td_proc->p_fd, fd, NULL, 0, &file,
76	    NULL) != 0) {
77		return;
78	}
79	fdclose(curthread->td_proc->p_fd, file, fd, curthread);
80}
81
82static inline void
83fd_install(unsigned int fd, struct linux_file *filp)
84{
85	struct file *file;
86
87	if (fget_unlocked(curthread->td_proc->p_fd, fd, NULL, 0, &file,
88	    NULL) != 0) {
89		file = NULL;
90	}
91	filp->_file = file;
92        finit(file, filp->f_mode, DTYPE_DEV, filp, &linuxfileops);
93}
94
95static inline int
96get_unused_fd(void)
97{
98	struct file *file;
99	int error;
100	int fd;
101
102	error = falloc(curthread, &file, &fd, 0);
103	if (error)
104		return -error;
105	return fd;
106}
107
108static inline struct linux_file *
109_alloc_file(int mode, const struct file_operations *fops)
110{
111	struct linux_file *filp;
112
113	filp = kzalloc(sizeof(*filp), GFP_KERNEL);
114	if (filp == NULL)
115		return (NULL);
116	filp->f_op = fops;
117	filp->f_mode = mode;
118
119	return filp;
120}
121
122#define	alloc_file(mnt, root, mode, fops)	_alloc_file((mode), (fops))
123
124#define	file	linux_file
125#define	fget	linux_fget
126
127#endif	/* _LINUX_FILE_H_ */
128