xref: /freebsd/sys/compat/linuxkpi/common/include/linux/fs.h (revision 272a12639440c2865fefba8b38771f8dd0ac5778)
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/param.h>
33 #include <sys/systm.h>
34 #include <sys/conf.h>
35 #include <sys/vnode.h>
36 #include <sys/file.h>
37 #include <sys/filedesc.h>
38 #include <linux/types.h>
39 #include <linux/wait.h>
40 #include <linux/semaphore.h>
41 #include <linux/spinlock.h>
42 #include <linux/dcache.h>
43 #include <linux/capability.h>
44 #include <linux/wait_bit.h>
45 #include <linux/kernel.h>
46 #include <linux/mount.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 typedef unsigned int fop_flags_t;
138 
139 struct file_operations {
140 	struct module *owner;
141 	fop_flags_t fop_flags; /* Unused on FreeBSD. */
142 	ssize_t (*read)(struct linux_file *, char __user *, size_t, off_t *);
143 	ssize_t (*write)(struct linux_file *, const char __user *, size_t, off_t *);
144 	unsigned int (*poll) (struct linux_file *, struct poll_table_struct *);
145 	long (*unlocked_ioctl)(struct linux_file *, unsigned int, unsigned long);
146 	long (*compat_ioctl)(struct linux_file *, unsigned int, unsigned long);
147 	int (*mmap)(struct linux_file *, struct vm_area_struct *);
148 	int (*open)(struct inode *, struct file *);
149 	int (*release)(struct inode *, struct linux_file *);
150 	int (*fasync)(int, struct linux_file *, int);
151 
152 /* Although not supported in FreeBSD, to align with Linux code
153  * we are adding llseek() only when it is mapped to no_llseek which returns
154  * an illegal seek error
155  */
156 	off_t (*llseek)(struct linux_file *, off_t, int);
157 /*
158  * Not supported in FreeBSD. That's ok, we never call it and it allows some
159  * drivers like DRM drivers to compile without changes.
160  */
161 	void (*show_fdinfo)(struct seq_file *, struct file *);
162 #if 0
163 	/* We do not support these methods.  Don't permit them to compile. */
164 	loff_t (*llseek)(struct file *, loff_t, int);
165 	ssize_t (*aio_read)(struct kiocb *, const struct iovec *,
166 	    unsigned long, loff_t);
167 	ssize_t (*aio_write)(struct kiocb *, const struct iovec *,
168 	    unsigned long, loff_t);
169 	int (*readdir)(struct file *, void *, filldir_t);
170 	int (*ioctl)(struct inode *, struct file *, unsigned int,
171 	    unsigned long);
172 	int (*flush)(struct file *, fl_owner_t id);
173 	int (*fsync)(struct file *, struct dentry *, int datasync);
174 	int (*aio_fsync)(struct kiocb *, int datasync);
175 	int (*lock)(struct file *, int, struct file_lock *);
176 	ssize_t (*sendpage)(struct file *, struct page *, int, size_t,
177 	    loff_t *, int);
178 	unsigned long (*get_unmapped_area)(struct file *, unsigned long,
179 	    unsigned long, unsigned long, unsigned long);
180 	int (*check_flags)(int);
181 	int (*flock)(struct file *, int, struct file_lock *);
182 	ssize_t (*splice_write)(struct pipe_inode_info *, struct file *,
183 	    loff_t *, size_t, unsigned int);
184 	ssize_t (*splice_read)(struct file *, loff_t *,
185 	    struct pipe_inode_info *, size_t, unsigned int);
186 	int (*setlease)(struct file *, long, struct file_lock **);
187 #endif
188 };
189 
190 #define	FOP_BUFFER_RASYNC	(1 << 0)
191 #define	FOP_BUFFER_WASYNC	(1 << 1)
192 #define	FOP_MMAP_SYNC		(1 << 2)
193 #define	FOP_DIO_PARALLEL_WRITE	(1 << 3)
194 #define	FOP_HUGE_PAGES		(1 << 4)
195 #define	FOP_UNSIGNED_OFFSET	(1 << 5)
196 
197 #define	fops_get(fops)		(fops)
198 #define	replace_fops(f, fops)	((f)->f_op = (fops))
199 
200 #define	FMODE_READ	FREAD
201 #define	FMODE_WRITE	FWRITE
202 #define	FMODE_EXEC	FEXEC
203 #define	FMODE_UNSIGNED_OFFSET	0x2000
204 int __register_chrdev(unsigned int major, unsigned int baseminor,
205     unsigned int count, const char *name,
206     const struct file_operations *fops);
207 int __register_chrdev_p(unsigned int major, unsigned int baseminor,
208     unsigned int count, const char *name,
209     const struct file_operations *fops, uid_t uid,
210     gid_t gid, int mode);
211 void __unregister_chrdev(unsigned int major, unsigned int baseminor,
212     unsigned int count, const char *name);
213 
214 static inline void
unregister_chrdev(unsigned int major,const char * name)215 unregister_chrdev(unsigned int major, const char *name)
216 {
217 
218 	__unregister_chrdev(major, 0, 256, name);
219 }
220 
221 static inline int
register_chrdev(unsigned int major,const char * name,const struct file_operations * fops)222 register_chrdev(unsigned int major, const char *name,
223     const struct file_operations *fops)
224 {
225 
226 	return (__register_chrdev(major, 0, 256, name, fops));
227 }
228 
229 static inline int
register_chrdev_p(unsigned int major,const char * name,const struct file_operations * fops,uid_t uid,gid_t gid,int mode)230 register_chrdev_p(unsigned int major, const char *name,
231     const struct file_operations *fops, uid_t uid, gid_t gid, int mode)
232 {
233 
234 	return (__register_chrdev_p(major, 0, 256, name, fops, uid, gid, mode));
235 }
236 
237 static inline int
register_chrdev_region(dev_t dev,unsigned range,const char * name)238 register_chrdev_region(dev_t dev, unsigned range, const char *name)
239 {
240 
241 	return 0;
242 }
243 
244 static inline void
unregister_chrdev_region(dev_t dev,unsigned range)245 unregister_chrdev_region(dev_t dev, unsigned range)
246 {
247 
248 	return;
249 }
250 
251 static inline int
alloc_chrdev_region(dev_t * dev,unsigned baseminor,unsigned count,const char * name)252 alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count,
253 			const char *name)
254 {
255 
256 	return 0;
257 }
258 
259 /* No current support for seek op in FreeBSD */
260 static inline int
nonseekable_open(struct inode * inode,struct file * filp)261 nonseekable_open(struct inode *inode, struct file *filp)
262 {
263 	return 0;
264 }
265 
266 static inline int
simple_open(struct inode * inode,struct file * filp)267 simple_open(struct inode *inode, struct file *filp)
268 {
269 	filp->private_data = inode->i_private;
270 	return 0;
271 }
272 
273 extern unsigned int linux_iminor(struct inode *);
274 #define	iminor(...) linux_iminor(__VA_ARGS__)
275 
276 static inline struct linux_file *
get_file(struct linux_file * f)277 get_file(struct linux_file *f)
278 {
279 
280 	refcount_acquire(f->_file == NULL ? &f->f_count : &f->_file->f_count);
281 	return (f);
282 }
283 
284 struct linux_file * linux_get_file_rcu(struct linux_file **f);
285 struct linux_file * get_file_active(struct linux_file **f);
286 #if defined(LINUXKPI_VERSION) && LINUXKPI_VERSION < 60700
287 static inline bool
get_file_rcu(struct linux_file * f)288 get_file_rcu(struct linux_file *f)
289 {
290 	return (refcount_acquire_if_not_zero(
291 	    f->_file == NULL ? &f->f_count : &f->_file->f_count));
292 }
293 #else
294 #define	get_file_rcu(f)	linux_get_file_rcu(f)
295 #endif
296 
297 static inline struct inode *
igrab(struct inode * inode)298 igrab(struct inode *inode)
299 {
300 	int error;
301 
302 	error = vget(inode, 0);
303 	if (error)
304 		return (NULL);
305 
306 	return (inode);
307 }
308 
309 static inline void
iput(struct inode * inode)310 iput(struct inode *inode)
311 {
312 
313 	vrele(inode);
314 }
315 
316 static inline loff_t
no_llseek(struct file * file,loff_t offset,int whence)317 no_llseek(struct file *file, loff_t offset, int whence)
318 {
319 
320 	return (-ESPIPE);
321 }
322 
323 static inline loff_t
default_llseek(struct file * file,loff_t offset,int whence)324 default_llseek(struct file *file, loff_t offset, int whence)
325 {
326 	return (no_llseek(file, offset, whence));
327 }
328 
329 static inline loff_t
generic_file_llseek(struct file * file,loff_t offset,int whence)330 generic_file_llseek(struct file *file, loff_t offset, int whence)
331 {
332 	return (no_llseek(file, offset, whence));
333 }
334 
335 static inline loff_t
noop_llseek(struct linux_file * file,loff_t offset,int whence)336 noop_llseek(struct linux_file *file, loff_t offset, int whence)
337 {
338 
339 	return (file->_file->f_offset);
340 }
341 
342 static inline struct vnode *
file_inode(const struct linux_file * file)343 file_inode(const struct linux_file *file)
344 {
345 
346 	return (file->f_vnode);
347 }
348 
349 static inline int
call_mmap(struct linux_file * file,struct vm_area_struct * vma)350 call_mmap(struct linux_file *file, struct vm_area_struct *vma)
351 {
352 
353 	return (file->f_op->mmap(file, vma));
354 }
355 
356 static inline void
i_size_write(struct inode * inode,loff_t i_size)357 i_size_write(struct inode *inode, loff_t i_size)
358 {
359 }
360 
361 /*
362  * simple_read_from_buffer: copy data from kernel-space origin
363  * buffer into user-space destination buffer
364  *
365  * @dest: destination buffer
366  * @read_size: number of bytes to be transferred
367  * @ppos: starting transfer position pointer
368  * @orig: origin buffer
369  * @buf_size: size of destination and origin buffers
370  *
371  * Return value:
372  * On success, total bytes copied with *ppos incremented accordingly.
373  * On failure, negative value.
374  */
375 static inline ssize_t
simple_read_from_buffer(void __user * dest,size_t read_size,loff_t * ppos,void * orig,size_t buf_size)376 simple_read_from_buffer(void __user *dest, size_t read_size, loff_t *ppos,
377     void *orig, size_t buf_size)
378 {
379 	void *read_pos = ((char *) orig) + *ppos;
380 	size_t buf_remain = buf_size - *ppos;
381 	ssize_t num_read;
382 
383 	if (*ppos >= buf_size || read_size == 0)
384 		return (0);
385 
386 	if (read_size > buf_remain)
387 		read_size = buf_remain;
388 
389 	/* copy_to_user returns number of bytes NOT read */
390 	num_read = read_size - copy_to_user(dest, read_pos, read_size);
391 	if (num_read == 0)
392 		return -EFAULT;
393 	*ppos += num_read;
394 
395 	return (num_read);
396 }
397 
398 MALLOC_DECLARE(M_LSATTR);
399 
400 #define	__DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt, __wrfunc)\
401 static inline int							\
402 __fops ## _open(struct inode *inode, struct file *filp)			\
403 {									\
404 	return (simple_attr_open(inode, filp, __get, __set, __fmt));	\
405 }									\
406 static const struct file_operations __fops = {				\
407 	.owner	 = THIS_MODULE,						\
408 	.open	 = __fops ## _open,					\
409 	.release = simple_attr_release,					\
410 	.read	 = simple_attr_read,					\
411 	.write	 = __wrfunc,						\
412 	.llseek	 = no_llseek						\
413 }
414 
415 #define	DEFINE_SIMPLE_ATTRIBUTE(fops, get, set, fmt)			\
416 	__DEFINE_SIMPLE_ATTRIBUTE(fops, get, set, fmt, simple_attr_write)
417 #define	DEFINE_SIMPLE_ATTRIBUTE_SIGNED(fops, get, set, fmt)		\
418 	__DEFINE_SIMPLE_ATTRIBUTE(fops, get, set, fmt, simple_attr_write_signed)
419 
420 int simple_attr_open(struct inode *inode, struct file *filp,
421     int (*get)(void *, uint64_t *), int (*set)(void *, uint64_t),
422     const char *fmt);
423 
424 int simple_attr_release(struct inode *inode, struct file *filp);
425 
426 ssize_t simple_attr_read(struct file *filp, char __user *buf, size_t read_size,
427     loff_t *ppos);
428 
429 ssize_t simple_attr_write(struct file *filp, const char __user *buf,
430     size_t write_size, loff_t *ppos);
431 
432 ssize_t simple_attr_write_signed(struct file *filp, const char __user *buf,
433 	    size_t write_size, loff_t *ppos);
434 
435 #endif /* _LINUXKPI_LINUX_FS_H_ */
436