xref: /freebsd/sys/compat/linuxkpi/common/include/linux/fs.h (revision 63f537551380d2dab29fa402ad1269feae17e594)
1 /*-
2  * Copyright (c) 2010 Isilon Systems, Inc.
3  * Copyright (c) 2010 iX Systems, Inc.
4  * Copyright (c) 2010 Panasas, Inc.
5  * Copyright (c) 2013-2018 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	_LINUXKPI_LINUX_FS_H_
30 #define	_LINUXKPI_LINUX_FS_H_
31 
32 #include <sys/cdefs.h>
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/conf.h>
36 #include <sys/vnode.h>
37 #include <sys/file.h>
38 #include <sys/filedesc.h>
39 #include <linux/types.h>
40 #include <linux/wait.h>
41 #include <linux/semaphore.h>
42 #include <linux/spinlock.h>
43 #include <linux/dcache.h>
44 #include <linux/capability.h>
45 #include <linux/wait_bit.h>
46 #include <linux/kernel.h>
47 #include <linux/mutex.h>
48 
49 struct module;
50 struct kiocb;
51 struct iovec;
52 struct dentry;
53 struct page;
54 struct file_lock;
55 struct pipe_inode_info;
56 struct vm_area_struct;
57 struct poll_table_struct;
58 struct files_struct;
59 struct pfs_node;
60 struct linux_cdev;
61 
62 #define	inode	vnode
63 #define	i_cdev	v_rdev
64 #define	i_private v_data
65 
66 #define	S_IRUGO	(S_IRUSR | S_IRGRP | S_IROTH)
67 #define	S_IWUGO	(S_IWUSR | S_IWGRP | S_IWOTH)
68 
69 typedef struct files_struct *fl_owner_t;
70 
71 struct file_operations;
72 
73 struct linux_file_wait_queue {
74 	struct wait_queue wq;
75 	struct wait_queue_head *wqh;
76 	atomic_t state;
77 #define	LINUX_FWQ_STATE_INIT 0
78 #define	LINUX_FWQ_STATE_NOT_READY 1
79 #define	LINUX_FWQ_STATE_QUEUED 2
80 #define	LINUX_FWQ_STATE_READY 3
81 #define	LINUX_FWQ_STATE_MAX 4
82 };
83 
84 struct linux_file {
85 	struct file	*_file;
86 	const struct file_operations	*f_op;
87 	void		*private_data;
88 	int		f_flags;
89 	int		f_mode;	/* Just starting mode. */
90 	struct dentry	*f_dentry;
91 	struct dentry	f_dentry_store;
92 	struct selinfo	f_selinfo;
93 	struct sigio	*f_sigio;
94 	struct vnode	*f_vnode;
95 #define	f_inode	f_vnode
96 	volatile u_int	f_count;
97 
98 	/* anonymous shmem object */
99 	vm_object_t	f_shmem;
100 
101 	/* kqfilter support */
102 	int		f_kqflags;
103 #define	LINUX_KQ_FLAG_HAS_READ (1 << 0)
104 #define	LINUX_KQ_FLAG_HAS_WRITE (1 << 1)
105 #define	LINUX_KQ_FLAG_NEED_READ (1 << 2)
106 #define	LINUX_KQ_FLAG_NEED_WRITE (1 << 3)
107 	/* protects f_selinfo.si_note */
108 	spinlock_t	f_kqlock;
109 	struct linux_file_wait_queue f_wait_queue;
110 
111 	/* pointer to associated character device, if any */
112 	struct linux_cdev *f_cdev;
113 
114 	struct rcu_head	rcu;
115 };
116 
117 #define	file		linux_file
118 #define	fasync_struct	sigio *
119 
120 #define	fasync_helper(fd, filp, on, queue)				\
121 ({									\
122 	if ((on))							\
123 		*(queue) = &(filp)->f_sigio;				\
124 	else								\
125 		*(queue) = NULL;					\
126 	0;								\
127 })
128 
129 #define	kill_fasync(queue, sig, pollstat)				\
130 do {									\
131 	if (*(queue) != NULL)						\
132 		pgsigio(*(queue), (sig), 0);				\
133 } while (0)
134 
135 typedef int (*filldir_t)(void *, const char *, int, off_t, u64, unsigned);
136 
137 struct file_operations {
138 	struct module *owner;
139 	ssize_t (*read)(struct linux_file *, char __user *, size_t, off_t *);
140 	ssize_t (*write)(struct linux_file *, const char __user *, size_t, off_t *);
141 	unsigned int (*poll) (struct linux_file *, struct poll_table_struct *);
142 	long (*unlocked_ioctl)(struct linux_file *, unsigned int, unsigned long);
143 	long (*compat_ioctl)(struct linux_file *, unsigned int, unsigned long);
144 	int (*mmap)(struct linux_file *, struct vm_area_struct *);
145 	int (*open)(struct inode *, struct file *);
146 	int (*release)(struct inode *, struct linux_file *);
147 	int (*fasync)(int, struct linux_file *, int);
148 
149 /* Although not supported in FreeBSD, to align with Linux code
150  * we are adding llseek() only when it is mapped to no_llseek which returns
151  * an illegal seek error
152  */
153 	off_t (*llseek)(struct linux_file *, off_t, int);
154 #if 0
155 	/* We do not support these methods.  Don't permit them to compile. */
156 	loff_t (*llseek)(struct file *, loff_t, int);
157 	ssize_t (*aio_read)(struct kiocb *, const struct iovec *,
158 	    unsigned long, loff_t);
159 	ssize_t (*aio_write)(struct kiocb *, const struct iovec *,
160 	    unsigned long, loff_t);
161 	int (*readdir)(struct file *, void *, filldir_t);
162 	int (*ioctl)(struct inode *, struct file *, unsigned int,
163 	    unsigned long);
164 	int (*flush)(struct file *, fl_owner_t id);
165 	int (*fsync)(struct file *, struct dentry *, int datasync);
166 	int (*aio_fsync)(struct kiocb *, int datasync);
167 	int (*lock)(struct file *, int, struct file_lock *);
168 	ssize_t (*sendpage)(struct file *, struct page *, int, size_t,
169 	    loff_t *, int);
170 	unsigned long (*get_unmapped_area)(struct file *, unsigned long,
171 	    unsigned long, unsigned long, unsigned long);
172 	int (*check_flags)(int);
173 	int (*flock)(struct file *, int, struct file_lock *);
174 	ssize_t (*splice_write)(struct pipe_inode_info *, struct file *,
175 	    loff_t *, size_t, unsigned int);
176 	ssize_t (*splice_read)(struct file *, loff_t *,
177 	    struct pipe_inode_info *, size_t, unsigned int);
178 	int (*setlease)(struct file *, long, struct file_lock **);
179 #endif
180 };
181 #define	fops_get(fops)		(fops)
182 #define	replace_fops(f, fops)	((f)->f_op = (fops))
183 
184 #define	FMODE_READ	FREAD
185 #define	FMODE_WRITE	FWRITE
186 #define	FMODE_EXEC	FEXEC
187 #define	FMODE_UNSIGNED_OFFSET	0x2000
188 int __register_chrdev(unsigned int major, unsigned int baseminor,
189     unsigned int count, const char *name,
190     const struct file_operations *fops);
191 int __register_chrdev_p(unsigned int major, unsigned int baseminor,
192     unsigned int count, const char *name,
193     const struct file_operations *fops, uid_t uid,
194     gid_t gid, int mode);
195 void __unregister_chrdev(unsigned int major, unsigned int baseminor,
196     unsigned int count, const char *name);
197 
198 static inline void
199 unregister_chrdev(unsigned int major, const char *name)
200 {
201 
202 	__unregister_chrdev(major, 0, 256, name);
203 }
204 
205 static inline int
206 register_chrdev(unsigned int major, const char *name,
207     const struct file_operations *fops)
208 {
209 
210 	return (__register_chrdev(major, 0, 256, name, fops));
211 }
212 
213 static inline int
214 register_chrdev_p(unsigned int major, const char *name,
215     const struct file_operations *fops, uid_t uid, gid_t gid, int mode)
216 {
217 
218 	return (__register_chrdev_p(major, 0, 256, name, fops, uid, gid, mode));
219 }
220 
221 static inline int
222 register_chrdev_region(dev_t dev, unsigned range, const char *name)
223 {
224 
225 	return 0;
226 }
227 
228 static inline void
229 unregister_chrdev_region(dev_t dev, unsigned range)
230 {
231 
232 	return;
233 }
234 
235 static inline int
236 alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count,
237 			const char *name)
238 {
239 
240 	return 0;
241 }
242 
243 /* No current support for seek op in FreeBSD */
244 static inline int
245 nonseekable_open(struct inode *inode, struct file *filp)
246 {
247 	return 0;
248 }
249 
250 static inline int
251 simple_open(struct inode *inode, struct file *filp)
252 {
253 	filp->private_data = inode->i_private;
254 	return 0;
255 }
256 
257 extern unsigned int linux_iminor(struct inode *);
258 #define	iminor(...) linux_iminor(__VA_ARGS__)
259 
260 static inline struct linux_file *
261 get_file(struct linux_file *f)
262 {
263 
264 	refcount_acquire(f->_file == NULL ? &f->f_count : &f->_file->f_count);
265 	return (f);
266 }
267 
268 static inline bool
269 get_file_rcu(struct linux_file *f)
270 {
271 	return (refcount_acquire_if_not_zero(
272 	    f->_file == NULL ? &f->f_count : &f->_file->f_count));
273 }
274 
275 static inline struct inode *
276 igrab(struct inode *inode)
277 {
278 	int error;
279 
280 	error = vget(inode, 0);
281 	if (error)
282 		return (NULL);
283 
284 	return (inode);
285 }
286 
287 static inline void
288 iput(struct inode *inode)
289 {
290 
291 	vrele(inode);
292 }
293 
294 static inline loff_t
295 no_llseek(struct file *file, loff_t offset, int whence)
296 {
297 
298 	return (-ESPIPE);
299 }
300 
301 static inline loff_t
302 default_llseek(struct file *file, loff_t offset, int whence)
303 {
304 	return (no_llseek(file, offset, whence));
305 }
306 
307 static inline loff_t
308 generic_file_llseek(struct file *file, loff_t offset, int whence)
309 {
310 	return (no_llseek(file, offset, whence));
311 }
312 
313 static inline loff_t
314 noop_llseek(struct linux_file *file, loff_t offset, int whence)
315 {
316 
317 	return (file->_file->f_offset);
318 }
319 
320 static inline struct vnode *
321 file_inode(const struct linux_file *file)
322 {
323 
324 	return (file->f_vnode);
325 }
326 
327 static inline int
328 call_mmap(struct linux_file *file, struct vm_area_struct *vma)
329 {
330 
331 	return (file->f_op->mmap(file, vma));
332 }
333 
334 static inline void
335 i_size_write(struct inode *inode, loff_t i_size)
336 {
337 }
338 
339 /*
340  * simple_read_from_buffer: copy data from kernel-space origin
341  * buffer into user-space destination buffer
342  *
343  * @dest: destination buffer
344  * @read_size: number of bytes to be transferred
345  * @ppos: starting transfer position pointer
346  * @orig: origin buffer
347  * @buf_size: size of destination and origin buffers
348  *
349  * Return value:
350  * On success, total bytes copied with *ppos incremented accordingly.
351  * On failure, negative value.
352  */
353 static inline ssize_t
354 simple_read_from_buffer(void __user *dest, size_t read_size, loff_t *ppos,
355     void *orig, size_t buf_size)
356 {
357 	void *read_pos = ((char *) orig) + *ppos;
358 	size_t buf_remain = buf_size - *ppos;
359 	ssize_t num_read;
360 
361 	if (buf_remain < 0 || buf_remain > buf_size)
362 		return -EINVAL;
363 
364 	if (read_size > buf_remain)
365 		read_size = buf_remain;
366 
367 	/* copy_to_user returns number of bytes NOT read */
368 	num_read = read_size - copy_to_user(dest, read_pos, read_size);
369 	if (num_read == 0)
370 		return -EFAULT;
371 	*ppos += num_read;
372 
373 	return (num_read);
374 }
375 
376 MALLOC_DECLARE(M_LSATTR);
377 
378 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt)		\
379 static inline int							\
380 __fops ## _open(struct inode *inode, struct file *filp)			\
381 {									\
382 	return (simple_attr_open(inode, filp, __get, __set, __fmt));	\
383 }									\
384 static const struct file_operations __fops = {				\
385 	.owner	 = THIS_MODULE,						\
386 	.open	 = __fops ## _open,					\
387 	.release = simple_attr_release,					\
388 	.read	 = simple_attr_read,					\
389 	.write	 = simple_attr_write,					\
390 	.llseek	 = no_llseek						\
391 }
392 
393 int simple_attr_open(struct inode *inode, struct file *filp,
394     int (*get)(void *, uint64_t *), int (*set)(void *, uint64_t),
395     const char *fmt);
396 
397 int simple_attr_release(struct inode *inode, struct file *filp);
398 
399 ssize_t simple_attr_read(struct file *filp, char *buf, size_t read_size, loff_t *ppos);
400 
401 ssize_t simple_attr_write(struct file *filp, const char *buf, size_t write_size, loff_t *ppos);
402 
403 #endif /* _LINUXKPI_LINUX_FS_H_ */
404