fs.h 96.5 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8
#ifndef _LINUX_FS_H
#define _LINUX_FS_H


#include <linux/linkage.h>
#include <linux/wait.h>
#include <linux/kdev_t.h>
#include <linux/dcache.h>
9
#include <linux/path.h>
L
Linus Torvalds 已提交
10 11 12
#include <linux/stat.h>
#include <linux/cache.h>
#include <linux/list.h>
13
#include <linux/list_lru.h>
14
#include <linux/llist.h>
L
Linus Torvalds 已提交
15
#include <linux/radix-tree.h>
16
#include <linux/rbtree.h>
L
Linus Torvalds 已提交
17
#include <linux/init.h>
18
#include <linux/pid.h>
19
#include <linux/bug.h>
20
#include <linux/mutex.h>
21
#include <linux/rwsem.h>
22
#include <linux/capability.h>
23
#include <linux/semaphore.h>
M
Mark Fasheh 已提交
24
#include <linux/fiemap.h>
25
#include <linux/rculist_bl.h>
26
#include <linux/atomic.h>
27
#include <linux/shrinker.h>
28
#include <linux/migrate_mode.h>
29
#include <linux/uidgid.h>
30
#include <linux/lockdep.h>
31
#include <linux/percpu-rwsem.h>
D
David Howells 已提交
32
#include <linux/blk_types.h>
L
Linus Torvalds 已提交
33 34

#include <asm/byteorder.h>
35
#include <uapi/linux/fs.h>
L
Linus Torvalds 已提交
36

37
struct backing_dev_info;
38
struct export_operations;
39
struct hd_geometry;
L
Linus Torvalds 已提交
40 41
struct iovec;
struct nameidata;
42
struct kiocb;
A
Alexey Dobriyan 已提交
43
struct kobject;
L
Linus Torvalds 已提交
44 45 46 47 48
struct pipe_inode_info;
struct poll_table_struct;
struct kstatfs;
struct vm_area_struct;
struct vfsmount;
49
struct cred;
50
struct swap_info_struct;
51
struct seq_file;
52
struct workqueue_struct;
53
struct iov_iter;
54
struct vm_fault;
L
Linus Torvalds 已提交
55

56
extern void __init inode_init(void);
L
Linus Torvalds 已提交
57 58 59
extern void __init inode_init_early(void);
extern void __init files_init(unsigned long);

60
extern struct files_stat_struct files_stat;
E
Eric Dumazet 已提交
61
extern unsigned long get_max_files(void);
62 63 64
extern int sysctl_nr_open;
extern struct inodes_stat_t inodes_stat;
extern int leases_enable, lease_break_time;
K
Kees Cook 已提交
65 66
extern int sysctl_protected_symlinks;
extern int sysctl_protected_hardlinks;
67

L
Linus Torvalds 已提交
68 69 70
struct buffer_head;
typedef int (get_block_t)(struct inode *inode, sector_t iblock,
			struct buffer_head *bh_result, int create);
71
typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
72
			ssize_t bytes, void *private);
L
Linus Torvalds 已提交
73

D
David Howells 已提交
74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129
#define MAY_EXEC		0x00000001
#define MAY_WRITE		0x00000002
#define MAY_READ		0x00000004
#define MAY_APPEND		0x00000008
#define MAY_ACCESS		0x00000010
#define MAY_OPEN		0x00000020
#define MAY_CHDIR		0x00000040
/* called from RCU mode, don't block */
#define MAY_NOT_BLOCK		0x00000080

/*
 * flags in file.f_mode.  Note that FMODE_READ and FMODE_WRITE must correspond
 * to O_WRONLY and O_RDWR via the strange trick in __dentry_open()
 */

/* file is open for reading */
#define FMODE_READ		((__force fmode_t)0x1)
/* file is open for writing */
#define FMODE_WRITE		((__force fmode_t)0x2)
/* file is seekable */
#define FMODE_LSEEK		((__force fmode_t)0x4)
/* file can be accessed using pread */
#define FMODE_PREAD		((__force fmode_t)0x8)
/* file can be accessed using pwrite */
#define FMODE_PWRITE		((__force fmode_t)0x10)
/* File is opened for execution with sys_execve / sys_uselib */
#define FMODE_EXEC		((__force fmode_t)0x20)
/* File is opened with O_NDELAY (only set for block devices) */
#define FMODE_NDELAY		((__force fmode_t)0x40)
/* File is opened with O_EXCL (only set for block devices) */
#define FMODE_EXCL		((__force fmode_t)0x80)
/* File is opened using open(.., 3, ..) and is writeable only for ioctls
   (specialy hack for floppy.c) */
#define FMODE_WRITE_IOCTL	((__force fmode_t)0x100)
/* 32bit hashes as llseek() offset (for directories) */
#define FMODE_32BITHASH         ((__force fmode_t)0x200)
/* 64bit hashes as llseek() offset (for directories) */
#define FMODE_64BITHASH         ((__force fmode_t)0x400)

/*
 * Don't update ctime and mtime.
 *
 * Currently a special hack for the XFS open_by_handle ioctl, but we'll
 * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
 */
#define FMODE_NOCMTIME		((__force fmode_t)0x800)

/* Expect random access pattern */
#define FMODE_RANDOM		((__force fmode_t)0x1000)

/* File is huge (eg. /dev/kmem): treat loff_t as unsigned */
#define FMODE_UNSIGNED_OFFSET	((__force fmode_t)0x2000)

/* File is opened with O_PATH; almost nothing can be done with it */
#define FMODE_PATH		((__force fmode_t)0x4000)

130 131
/* File needs atomic accesses to f_pos */
#define FMODE_ATOMIC_POS	((__force fmode_t)0x8000)
132 133
/* Write access to underlying fs */
#define FMODE_WRITER		((__force fmode_t)0x10000)
134 135 136 137
/* Has read method(s) */
#define FMODE_CAN_READ          ((__force fmode_t)0x20000)
/* Has write method(s) */
#define FMODE_CAN_WRITE         ((__force fmode_t)0x40000)
138

D
David Howells 已提交
139
/* File was opened by fanotify and shouldn't generate fanotify events */
140
#define FMODE_NONOTIFY		((__force fmode_t)0x4000000)
D
David Howells 已提交
141 142 143 144 145 146 147 148 149

/*
 * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
 * that indicates that they should check the contents of the iovec are
 * valid, but not check the memory that the iovec elements
 * points too.
 */
#define CHECK_IOVEC_ONLY -1

D
David Howells 已提交
150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205
/*
 * The below are the various read and write types that we support. Some of
 * them include behavioral modifiers that send information down to the
 * block layer and IO scheduler. Terminology:
 *
 *	The block layer uses device plugging to defer IO a little bit, in
 *	the hope that we will see more IO very shortly. This increases
 *	coalescing of adjacent IO and thus reduces the number of IOs we
 *	have to send to the device. It also allows for better queuing,
 *	if the IO isn't mergeable. If the caller is going to be waiting
 *	for the IO, then he must ensure that the device is unplugged so
 *	that the IO is dispatched to the driver.
 *
 *	All IO is handled async in Linux. This is fine for background
 *	writes, but for reads or writes that someone waits for completion
 *	on, we want to notify the block layer and IO scheduler so that they
 *	know about it. That allows them to make better scheduling
 *	decisions. So when the below references 'sync' and 'async', it
 *	is referencing this priority hint.
 *
 * With that in mind, the available types are:
 *
 * READ			A normal read operation. Device will be plugged.
 * READ_SYNC		A synchronous read. Device is not plugged, caller can
 *			immediately wait on this read without caring about
 *			unplugging.
 * READA		Used for read-ahead operations. Lower priority, and the
 *			block layer could (in theory) choose to ignore this
 *			request if it runs into resource problems.
 * WRITE		A normal async write. Device will be plugged.
 * WRITE_SYNC		Synchronous write. Identical to WRITE, but passes down
 *			the hint that someone will be waiting on this IO
 *			shortly. The write equivalent of READ_SYNC.
 * WRITE_ODIRECT	Special case write for O_DIRECT only.
 * WRITE_FLUSH		Like WRITE_SYNC but with preceding cache flush.
 * WRITE_FUA		Like WRITE_SYNC but data is guaranteed to be on
 *			non-volatile media on completion.
 * WRITE_FLUSH_FUA	Combination of WRITE_FLUSH and FUA. The IO is preceded
 *			by a cache flush and data is guaranteed to be on
 *			non-volatile media on completion.
 *
 */
#define RW_MASK			REQ_WRITE
#define RWA_MASK		REQ_RAHEAD

#define READ			0
#define WRITE			RW_MASK
#define READA			RWA_MASK

#define READ_SYNC		(READ | REQ_SYNC)
#define WRITE_SYNC		(WRITE | REQ_SYNC | REQ_NOIDLE)
#define WRITE_ODIRECT		(WRITE | REQ_SYNC)
#define WRITE_FLUSH		(WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH)
#define WRITE_FUA		(WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA)
#define WRITE_FLUSH_FUA		(WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA)

L
Linus Torvalds 已提交
206 207 208 209
/*
 * Attribute flags.  These should be or-ed together to figure out what
 * has been changed!
 */
210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226
#define ATTR_MODE	(1 << 0)
#define ATTR_UID	(1 << 1)
#define ATTR_GID	(1 << 2)
#define ATTR_SIZE	(1 << 3)
#define ATTR_ATIME	(1 << 4)
#define ATTR_MTIME	(1 << 5)
#define ATTR_CTIME	(1 << 6)
#define ATTR_ATIME_SET	(1 << 7)
#define ATTR_MTIME_SET	(1 << 8)
#define ATTR_FORCE	(1 << 9) /* Not a change, but a change it */
#define ATTR_ATTR_FLAG	(1 << 10)
#define ATTR_KILL_SUID	(1 << 11)
#define ATTR_KILL_SGID	(1 << 12)
#define ATTR_FILE	(1 << 13)
#define ATTR_KILL_PRIV	(1 << 14)
#define ATTR_OPEN	(1 << 15) /* Truncating from open(O_TRUNC) */
#define ATTR_TIMES_SET	(1 << 16)
L
Linus Torvalds 已提交
227

M
Miklos Szeredi 已提交
228 229 230 231 232 233 234
/*
 * Whiteout is represented by a char device.  The following constants define the
 * mode and device number to use.
 */
#define WHITEOUT_MODE 0
#define WHITEOUT_DEV 0

L
Linus Torvalds 已提交
235 236 237 238 239 240 241 242 243 244 245 246
/*
 * This is the Inode Attributes structure, used for notify_change().  It
 * uses the above definitions as flags, to know which values have changed.
 * Also, in this manner, a Filesystem can look at only the values it cares
 * about.  Basically, these are the attributes that the VFS layer can
 * request to change from the FS layer.
 *
 * Derek Atkins <warlord@MIT.EDU> 94-10-20
 */
struct iattr {
	unsigned int	ia_valid;
	umode_t		ia_mode;
247 248
	kuid_t		ia_uid;
	kgid_t		ia_gid;
L
Linus Torvalds 已提交
249 250 251 252
	loff_t		ia_size;
	struct timespec	ia_atime;
	struct timespec	ia_mtime;
	struct timespec	ia_ctime;
253 254

	/*
L
Lucas De Marchi 已提交
255
	 * Not an attribute, but an auxiliary info for filesystems wanting to
256 257 258 259
	 * implement an ftruncate() like method.  NOTE: filesystem should
	 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
	 */
	struct file	*ia_file;
L
Linus Torvalds 已提交
260 261 262 263 264 265 266
};

/*
 * Includes for diskquotas.
 */
#include <linux/quota.h>

267 268 269 270 271 272
/*
 * Maximum number of layers of fs stack.  Needs to be limited to
 * prevent kernel stack overflow
 */
#define FILESYSTEM_MAX_STACK_DEPTH 2

273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290
/** 
 * enum positive_aop_returns - aop return codes with specific semantics
 *
 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
 * 			    completed, that the page is still locked, and
 * 			    should be considered active.  The VM uses this hint
 * 			    to return the page to the active list -- it won't
 * 			    be a candidate for writeback again in the near
 * 			    future.  Other callers must be careful to unlock
 * 			    the page if they get this return.  Returned by
 * 			    writepage(); 
 *
 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
 *  			unlocked it and the page might have been truncated.
 *  			The caller should back up to acquiring a new page and
 *  			trying again.  The aop will be taking reasonable
 *  			precautions not to livelock.  If the caller held a page
 *  			reference, it should drop it before retrying.  Returned
N
Nick Piggin 已提交
291
 *  			by readpage().
292 293 294 295 296 297 298 299 300 301 302 303
 *
 * address_space_operation functions return these large constants to indicate
 * special semantics to the caller.  These are much larger than the bytes in a
 * page to allow for functions that return the number of bytes operated on in a
 * given page.
 */

enum positive_aop_returns {
	AOP_WRITEPAGE_ACTIVATE	= 0x80000,
	AOP_TRUNCATED_PAGE	= 0x80001,
};

304
#define AOP_FLAG_UNINTERRUPTIBLE	0x0001 /* will not do a short write */
N
Nick Piggin 已提交
305
#define AOP_FLAG_CONT_EXPAND		0x0002 /* called from cont_expand */
306 307 308
#define AOP_FLAG_NOFS			0x0004 /* used by filesystem to direct
						* helper code (eg buffer layer)
						* to clear GFP_FS from alloc */
309

L
Linus Torvalds 已提交
310 311 312 313 314 315 316
/*
 * oh the beauties of C type declarations.
 */
struct page;
struct address_space;
struct writeback_control;

317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337
/*
 * "descriptor" for what we're up to with a read.
 * This allows us to use the same read code yet
 * have multiple different users of the data that
 * we read from a file.
 *
 * The simplest case just copies the data to user
 * mode.
 */
typedef struct {
	size_t written;
	size_t count;
	union {
		char __user *buf;
		void *data;
	} arg;
	int error;
} read_descriptor_t;

typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
		unsigned long, unsigned long);
N
Nick Piggin 已提交
338

L
Linus Torvalds 已提交
339 340 341 342 343 344 345
struct address_space_operations {
	int (*writepage)(struct page *page, struct writeback_control *wbc);
	int (*readpage)(struct file *, struct page *);

	/* Write back some dirty pages from this mapping. */
	int (*writepages)(struct address_space *, struct writeback_control *);

346
	/* Set a page dirty.  Return true if this dirtied it */
L
Linus Torvalds 已提交
347 348 349 350 351
	int (*set_page_dirty)(struct page *page);

	int (*readpages)(struct file *filp, struct address_space *mapping,
			struct list_head *pages, unsigned nr_pages);

352 353 354 355 356 357 358
	int (*write_begin)(struct file *, struct address_space *mapping,
				loff_t pos, unsigned len, unsigned flags,
				struct page **pagep, void **fsdata);
	int (*write_end)(struct file *, struct address_space *mapping,
				loff_t pos, unsigned len, unsigned copied,
				struct page *page, void *fsdata);

L
Linus Torvalds 已提交
359 360
	/* Unfortunately this kludge is needed for FIBMAP. Don't use it */
	sector_t (*bmap)(struct address_space *, sector_t);
361
	void (*invalidatepage) (struct page *, unsigned int, unsigned int);
A
Al Viro 已提交
362
	int (*releasepage) (struct page *, gfp_t);
363
	void (*freepage)(struct page *);
A
Al Viro 已提交
364
	ssize_t (*direct_IO)(int, struct kiocb *, struct iov_iter *iter, loff_t offset);
365
	/*
366 367
	 * migrate the contents of a page to the specified target. If
	 * migrate_mode is MIGRATE_ASYNC, it must not block.
368
	 */
369
	int (*migratepage) (struct address_space *,
370
			struct page *, struct page *, enum migrate_mode);
371
	int (*launder_page) (struct page *);
372
	int (*is_partially_uptodate) (struct page *, unsigned long,
373
					unsigned long);
374
	void (*is_dirty_writeback) (struct page *, bool *, bool *);
375
	int (*error_remove_page)(struct address_space *, struct page *);
376 377

	/* swapfile support */
378 379 380
	int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
				sector_t *span);
	void (*swap_deactivate)(struct file *file);
L
Linus Torvalds 已提交
381 382
};

J
Jens Axboe 已提交
383 384
extern const struct address_space_operations empty_aops;

385 386 387 388 389 390 391 392 393 394 395 396
/*
 * pagecache_write_begin/pagecache_write_end must be used by general code
 * to write into the pagecache.
 */
int pagecache_write_begin(struct file *, struct address_space *mapping,
				loff_t pos, unsigned len, unsigned flags,
				struct page **pagep, void **fsdata);

int pagecache_write_end(struct file *, struct address_space *mapping,
				loff_t pos, unsigned len, unsigned copied,
				struct page *page, void *fsdata);

L
Linus Torvalds 已提交
397 398 399
struct address_space {
	struct inode		*host;		/* owner: inode, block_device */
	struct radix_tree_root	page_tree;	/* radix tree of all pages */
N
Nick Piggin 已提交
400
	spinlock_t		tree_lock;	/* and lock protecting it */
401
	atomic_t		i_mmap_writable;/* count VM_SHARED mappings */
402
	struct rb_root		i_mmap;		/* tree of private and shared mappings */
403
	struct rw_semaphore	i_mmap_rwsem;	/* protect tree, count, list */
404
	/* Protected by tree_lock together with the radix tree */
L
Linus Torvalds 已提交
405
	unsigned long		nrpages;	/* number of total pages */
406
	unsigned long		nrshadows;	/* number of shadow entries */
L
Linus Torvalds 已提交
407
	pgoff_t			writeback_index;/* writeback starts here */
408
	const struct address_space_operations *a_ops;	/* methods */
L
Linus Torvalds 已提交
409 410 411
	unsigned long		flags;		/* error bits/gfp mask */
	spinlock_t		private_lock;	/* for use by the address_space */
	struct list_head	private_list;	/* ditto */
412
	void			*private_data;	/* ditto */
L
Linus Torvalds 已提交
413 414 415
} __attribute__((aligned(sizeof(long))));
	/*
	 * On most architectures that alignment is already the case; but
L
Lucas De Marchi 已提交
416
	 * must be enforced here for CRIS, to let the least significant bit
L
Linus Torvalds 已提交
417 418
	 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
	 */
419
struct request_queue;
L
Linus Torvalds 已提交
420 421 422

struct block_device {
	dev_t			bd_dev;  /* not a kdev_t - it's a search key */
423
	int			bd_openers;
L
Linus Torvalds 已提交
424
	struct inode *		bd_inode;	/* will die */
425
	struct super_block *	bd_super;
426
	struct mutex		bd_mutex;	/* open/close mutex */
L
Linus Torvalds 已提交
427
	struct list_head	bd_inodes;
428
	void *			bd_claiming;
L
Linus Torvalds 已提交
429 430
	void *			bd_holder;
	int			bd_holders;
431
	bool			bd_write_holder;
432
#ifdef CONFIG_SYSFS
433
	struct list_head	bd_holder_disks;
434
#endif
L
Linus Torvalds 已提交
435 436 437 438 439 440 441
	struct block_device *	bd_contains;
	unsigned		bd_block_size;
	struct hd_struct *	bd_part;
	/* number of times partitions within this device have been opened. */
	unsigned		bd_part_count;
	int			bd_invalidated;
	struct gendisk *	bd_disk;
442
	struct request_queue *  bd_queue;
L
Linus Torvalds 已提交
443 444 445 446 447 448 449 450
	struct list_head	bd_list;
	/*
	 * Private data.  You must have bd_claim'ed the block_device
	 * to use this.  NOTE:  bd_claim allows an owner to claim
	 * the same device multiple times, the owner must take special
	 * care to not mess up bd_private for that case.
	 */
	unsigned long		bd_private;
451 452 453 454 455

	/* The counter of freeze processes */
	int			bd_fsfreeze_count;
	/* Mutex for freeze */
	struct mutex		bd_fsfreeze_mutex;
L
Linus Torvalds 已提交
456 457 458 459 460 461 462 463
};

/*
 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
 * radix trees
 */
#define PAGECACHE_TAG_DIRTY	0
#define PAGECACHE_TAG_WRITEBACK	1
464
#define PAGECACHE_TAG_TOWRITE	2
L
Linus Torvalds 已提交
465 466 467

int mapping_tagged(struct address_space *mapping, int tag);

468 469
static inline void i_mmap_lock_write(struct address_space *mapping)
{
470
	down_write(&mapping->i_mmap_rwsem);
471 472 473 474
}

static inline void i_mmap_unlock_write(struct address_space *mapping)
{
475
	up_write(&mapping->i_mmap_rwsem);
476 477
}

D
Davidlohr Bueso 已提交
478 479 480 481 482 483 484 485 486 487
static inline void i_mmap_lock_read(struct address_space *mapping)
{
	down_read(&mapping->i_mmap_rwsem);
}

static inline void i_mmap_unlock_read(struct address_space *mapping)
{
	up_read(&mapping->i_mmap_rwsem);
}

L
Linus Torvalds 已提交
488 489 490 491 492
/*
 * Might pages of this file be mapped into userspace?
 */
static inline int mapping_mapped(struct address_space *mapping)
{
493
	return	!RB_EMPTY_ROOT(&mapping->i_mmap);
L
Linus Torvalds 已提交
494 495 496 497 498 499 500
}

/*
 * Might pages of this file have been modified in userspace?
 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
 * marks vma as VM_SHARED if it is shared, and the file was opened for
 * writing i.e. vma may be mprotected writable even if now readonly.
501 502 503
 *
 * If i_mmap_writable is negative, no new writable mappings are allowed. You
 * can only deny writable mappings, if none exists right now.
L
Linus Torvalds 已提交
504 505 506
 */
static inline int mapping_writably_mapped(struct address_space *mapping)
{
507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529
	return atomic_read(&mapping->i_mmap_writable) > 0;
}

static inline int mapping_map_writable(struct address_space *mapping)
{
	return atomic_inc_unless_negative(&mapping->i_mmap_writable) ?
		0 : -EPERM;
}

static inline void mapping_unmap_writable(struct address_space *mapping)
{
	atomic_dec(&mapping->i_mmap_writable);
}

static inline int mapping_deny_writable(struct address_space *mapping)
{
	return atomic_dec_unless_positive(&mapping->i_mmap_writable) ?
		0 : -EBUSY;
}

static inline void mapping_allow_writable(struct address_space *mapping)
{
	atomic_inc(&mapping->i_mmap_writable);
L
Linus Torvalds 已提交
530 531 532 533 534 535 536 537 538 539 540 541 542
}

/*
 * Use sequence counter to get consistent i_size on 32-bit processors.
 */
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
#include <linux/seqlock.h>
#define __NEED_I_SIZE_ORDERED
#define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
#else
#define i_size_ordered_init(inode) do { } while (0)
#endif

A
Al Viro 已提交
543 544 545
struct posix_acl;
#define ACL_NOT_CACHED ((void *)(-1))

546 547 548 549 550 551 552 553 554
#define IOP_FASTPERM	0x0001
#define IOP_LOOKUP	0x0002
#define IOP_NOFOLLOW	0x0004

/*
 * Keep mostly read-only and often accessed (especially for
 * the RCU path lookup and 'stat' data) fields at the beginning
 * of the 'struct inode'
 */
L
Linus Torvalds 已提交
555
struct inode {
556
	umode_t			i_mode;
557
	unsigned short		i_opflags;
558 559
	kuid_t			i_uid;
	kgid_t			i_gid;
560 561 562 563 564 565 566
	unsigned int		i_flags;

#ifdef CONFIG_FS_POSIX_ACL
	struct posix_acl	*i_acl;
	struct posix_acl	*i_default_acl;
#endif

567 568
	const struct inode_operations	*i_op;
	struct super_block	*i_sb;
569
	struct address_space	*i_mapping;
570

571 572 573
#ifdef CONFIG_SECURITY
	void			*i_security;
#endif
574

575 576
	/* Stat data, not accessed from path walking */
	unsigned long		i_ino;
M
Miklos Szeredi 已提交
577 578 579 580 581 582 583 584 585 586 587
	/*
	 * Filesystems may only read i_nlink directly.  They shall use the
	 * following functions for modification:
	 *
	 *    (set|clear|inc|drop)_nlink
	 *    inode_(inc|dec)_link_count
	 */
	union {
		const unsigned int i_nlink;
		unsigned int __i_nlink;
	};
588
	dev_t			i_rdev;
589
	loff_t			i_size;
590 591 592
	struct timespec		i_atime;
	struct timespec		i_mtime;
	struct timespec		i_ctime;
593 594
	spinlock_t		i_lock;	/* i_blocks, i_bytes, maybe i_size */
	unsigned short          i_bytes;
595
	unsigned int		i_blkbits;
596 597 598 599 600 601 602 603 604
	blkcnt_t		i_blocks;

#ifdef __NEED_I_SIZE_ORDERED
	seqcount_t		i_size_seqcount;
#endif

	/* Misc */
	unsigned long		i_state;
	struct mutex		i_mutex;
605

606
	unsigned long		dirtied_when;	/* jiffies of first dirtying */
607
	unsigned long		dirtied_time_when;
608

L
Linus Torvalds 已提交
609
	struct hlist_node	i_hash;
N
Nick Piggin 已提交
610 611
	struct list_head	i_wb_list;	/* backing dev IO list */
	struct list_head	i_lru;		/* inode LRU list */
L
Linus Torvalds 已提交
612
	struct list_head	i_sb_list;
N
Nick Piggin 已提交
613
	union {
A
Al Viro 已提交
614
		struct hlist_head	i_dentry;
N
Nick Piggin 已提交
615 616
		struct rcu_head		i_rcu;
	};
617
	u64			i_version;
618
	atomic_t		i_count;
C
Christoph Hellwig 已提交
619
	atomic_t		i_dio_count;
620
	atomic_t		i_writecount;
M
Mimi Zohar 已提交
621 622 623
#ifdef CONFIG_IMA
	atomic_t		i_readcount; /* struct files open RO */
#endif
624
	const struct file_operations	*i_fop;	/* former ->i_op->default_file_ops */
625
	struct file_lock_context	*i_flctx;
L
Linus Torvalds 已提交
626 627
	struct address_space	i_data;
	struct list_head	i_devices;
628 629
	union {
		struct pipe_inode_info	*i_pipe;
630
		struct block_device	*i_bdev;
631
		struct cdev		*i_cdev;
632
	};
L
Linus Torvalds 已提交
633 634 635

	__u32			i_generation;

636 637
#ifdef CONFIG_FSNOTIFY
	__u32			i_fsnotify_mask; /* all events this inode cares about */
638
	struct hlist_head	i_fsnotify_marks;
R
Robert Love 已提交
639 640
#endif

641
	void			*i_private; /* fs or device private pointer */
L
Linus Torvalds 已提交
642 643
};

A
Al Viro 已提交
644 645 646 647 648
static inline int inode_unhashed(struct inode *inode)
{
	return hlist_unhashed(&inode->i_hash);
}

I
Ingo Molnar 已提交
649 650 651 652 653 654
/*
 * inode->i_mutex nesting subclasses for the lock validator:
 *
 * 0: the object of the current VFS operation
 * 1: parent
 * 2: child/target
655 656
 * 3: xattr
 * 4: second non-directory
657 658 659
 * 5: second parent (when locking independent directories in rename)
 *
 * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
660
 * non-directories at once.
I
Ingo Molnar 已提交
661 662
 *
 * The locking order between these classes is
663
 * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
I
Ingo Molnar 已提交
664 665 666 667 668 669
 */
enum inode_i_mutex_lock_class
{
	I_MUTEX_NORMAL,
	I_MUTEX_PARENT,
	I_MUTEX_CHILD,
I
Ingo Molnar 已提交
670
	I_MUTEX_XATTR,
671 672
	I_MUTEX_NONDIR2,
	I_MUTEX_PARENT2,
I
Ingo Molnar 已提交
673 674
};

675 676 677
void lock_two_nondirectories(struct inode *, struct inode*);
void unlock_two_nondirectories(struct inode *, struct inode*);

L
Linus Torvalds 已提交
678 679 680 681 682 683 684 685 686 687
/*
 * NOTE: in a 32bit arch with a preemptable kernel and
 * an UP compile the i_size_read/write must be atomic
 * with respect to the local cpu (unlike with preempt disabled),
 * but they don't need to be atomic with respect to other cpus like in
 * true SMP (so they need either to either locally disable irq around
 * the read or for example on x86 they can be still implemented as a
 * cmpxchg8b without the need of the lock prefix). For SMP compiles
 * and 64bit archs it makes no difference if preempt is enabled or not.
 */
J
Jan Engelhardt 已提交
688
static inline loff_t i_size_read(const struct inode *inode)
L
Linus Torvalds 已提交
689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710
{
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
	loff_t i_size;
	unsigned int seq;

	do {
		seq = read_seqcount_begin(&inode->i_size_seqcount);
		i_size = inode->i_size;
	} while (read_seqcount_retry(&inode->i_size_seqcount, seq));
	return i_size;
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
	loff_t i_size;

	preempt_disable();
	i_size = inode->i_size;
	preempt_enable();
	return i_size;
#else
	return inode->i_size;
#endif
}

711 712 713 714 715
/*
 * NOTE: unlike i_size_read(), i_size_write() does need locking around it
 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
 * can be lost, resulting in subsequent i_size_read() calls spinning forever.
 */
L
Linus Torvalds 已提交
716 717 718
static inline void i_size_write(struct inode *inode, loff_t i_size)
{
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
719
	preempt_disable();
L
Linus Torvalds 已提交
720 721 722
	write_seqcount_begin(&inode->i_size_seqcount);
	inode->i_size = i_size;
	write_seqcount_end(&inode->i_size_seqcount);
723
	preempt_enable();
L
Linus Torvalds 已提交
724 725 726 727 728 729 730 731 732
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
	preempt_disable();
	inode->i_size = i_size;
	preempt_enable();
#else
	inode->i_size = i_size;
#endif
}

733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757
/* Helper functions so that in most cases filesystems will
 * not need to deal directly with kuid_t and kgid_t and can
 * instead deal with the raw numeric values that are stored
 * in the filesystem.
 */
static inline uid_t i_uid_read(const struct inode *inode)
{
	return from_kuid(&init_user_ns, inode->i_uid);
}

static inline gid_t i_gid_read(const struct inode *inode)
{
	return from_kgid(&init_user_ns, inode->i_gid);
}

static inline void i_uid_write(struct inode *inode, uid_t uid)
{
	inode->i_uid = make_kuid(&init_user_ns, uid);
}

static inline void i_gid_write(struct inode *inode, gid_t gid)
{
	inode->i_gid = make_kgid(&init_user_ns, gid);
}

J
Jan Engelhardt 已提交
758
static inline unsigned iminor(const struct inode *inode)
L
Linus Torvalds 已提交
759 760 761 762
{
	return MINOR(inode->i_rdev);
}

J
Jan Engelhardt 已提交
763
static inline unsigned imajor(const struct inode *inode)
L
Linus Torvalds 已提交
764 765 766 767 768 769 770 771
{
	return MAJOR(inode->i_rdev);
}

extern struct block_device *I_BDEV(struct inode *inode);

struct fown_struct {
	rwlock_t lock;          /* protects pid, uid, euid fields */
772 773
	struct pid *pid;	/* pid or -pgrp where SIGIO should be sent */
	enum pid_type pid_type;	/* Kind of process group SIGIO should be sent to */
774
	kuid_t uid, euid;	/* uid/euid of process setting the owner */
L
Linus Torvalds 已提交
775 776 777 778 779 780 781
	int signum;		/* posix.1b rt signal to be delivered on IO */
};

/*
 * Track a single file's readahead state
 */
struct file_ra_state {
F
Fengguang Wu 已提交
782 783 784
	pgoff_t start;			/* where readahead started */
	unsigned int size;		/* # of readahead pages */
	unsigned int async_size;	/* do asynchronous readahead when
785
					   there are only # of pages ahead */
786

F
Fengguang Wu 已提交
787
	unsigned int ra_pages;		/* Maximum readahead window */
788
	unsigned int mmap_miss;		/* Cache miss stat for mmap accesses */
789
	loff_t prev_pos;		/* Cache last read() position */
L
Linus Torvalds 已提交
790 791
};

792 793 794 795 796
/*
 * Check if @index falls in the readahead windows.
 */
static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
{
797 798
	return (index >= ra->start &&
		index <  ra->start + ra->size);
799 800
}

L
Linus Torvalds 已提交
801
struct file {
E
Eric Dumazet 已提交
802
	union {
803
		struct llist_node	fu_llist;
E
Eric Dumazet 已提交
804 805
		struct rcu_head 	fu_rcuhead;
	} f_u;
806
	struct path		f_path;
807
	struct inode		*f_inode;	/* cached value */
808
	const struct file_operations	*f_op;
809 810

	/*
811
	 * Protects f_ep_links, f_flags.
812 813 814
	 * Must not be taken from IRQ context.
	 */
	spinlock_t		f_lock;
A
Al Viro 已提交
815
	atomic_long_t		f_count;
L
Linus Torvalds 已提交
816
	unsigned int 		f_flags;
817
	fmode_t			f_mode;
818
	struct mutex		f_pos_lock;
L
Linus Torvalds 已提交
819 820
	loff_t			f_pos;
	struct fown_struct	f_owner;
D
David Howells 已提交
821
	const struct cred	*f_cred;
L
Linus Torvalds 已提交
822 823
	struct file_ra_state	f_ra;

824
	u64			f_version;
825
#ifdef CONFIG_SECURITY
L
Linus Torvalds 已提交
826
	void			*f_security;
827
#endif
L
Linus Torvalds 已提交
828 829 830 831 832 833
	/* needed for tty driver, and maybe others */
	void			*private_data;

#ifdef CONFIG_EPOLL
	/* Used by fs/eventpoll.c to link all the hooks to this file */
	struct list_head	f_ep_links;
J
Jason Baron 已提交
834
	struct list_head	f_tfile_llink;
L
Linus Torvalds 已提交
835 836
#endif /* #ifdef CONFIG_EPOLL */
	struct address_space	*f_mapping;
A
Al Viro 已提交
837
} __attribute__((aligned(4)));	/* lest something weird decides that 2 is OK */
L
Linus Torvalds 已提交
838

839 840 841 842 843 844 845
struct file_handle {
	__u32 handle_bytes;
	int handle_type;
	/* file identifier */
	unsigned char f_handle[0];
};

A
Al Viro 已提交
846 847 848 849 850
static inline struct file *get_file(struct file *f)
{
	atomic_long_inc(&f->f_count);
	return f;
}
851
#define fput_atomic(x)	atomic_long_add_unless(&(x)->f_count, -1, 1)
A
Al Viro 已提交
852
#define file_count(x)	atomic_long_read(&(x)->f_count)
L
Linus Torvalds 已提交
853 854 855 856 857 858

#define	MAX_NON_LFS	((1UL<<31) - 1)

/* Page cache limit. The filesystems should put that into their s_maxbytes 
   limits, otherwise bad things can happen in VM. */ 
#if BITS_PER_LONG==32
C
Chuck Lever 已提交
859
#define MAX_LFS_FILESIZE	(((loff_t)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1) 
L
Linus Torvalds 已提交
860
#elif BITS_PER_LONG==64
861
#define MAX_LFS_FILESIZE 	((loff_t)0x7fffffffffffffffLL)
L
Linus Torvalds 已提交
862 863 864 865
#endif

#define FL_POSIX	1
#define FL_FLOCK	2
866
#define FL_DELEG	4	/* NFSv4 delegation */
L
Linus Torvalds 已提交
867
#define FL_ACCESS	8	/* not trying to lock, just looking */
868
#define FL_EXISTS	16	/* when unlocking, test for existence */
L
Linus Torvalds 已提交
869
#define FL_LEASE	32	/* lease held on this file */
870
#define FL_CLOSE	64	/* unlock on close */
L
Linus Torvalds 已提交
871
#define FL_SLEEP	128	/* A blocking lock */
872 873
#define FL_DOWNGRADE_PENDING	256 /* Lease is being downgraded */
#define FL_UNLOCK_PENDING	512 /* Lease is being broken */
874
#define FL_OFDLCK	1024	/* lock is "owned" by struct file */
C
Christoph Hellwig 已提交
875
#define FL_LAYOUT	2048	/* outstanding pNFS layout */
L
Linus Torvalds 已提交
876

877 878 879 880 881 882
/*
 * Special return value from posix_lock_file() and vfs_lock_file() for
 * asynchronous locking.
 */
#define FILE_LOCK_DEFERRED 1

883
/* legacy typedef, should eventually be removed */
884
typedef void *fl_owner_t;
L
Linus Torvalds 已提交
885

886 887
struct file_lock;

L
Linus Torvalds 已提交
888 889 890 891 892 893
struct file_lock_operations {
	void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
	void (*fl_release_private)(struct file_lock *);
};

struct lock_manager_operations {
J
J. Bruce Fields 已提交
894
	int (*lm_compare_owner)(struct file_lock *, struct file_lock *);
895
	unsigned long (*lm_owner_key)(struct file_lock *);
896 897
	void (*lm_get_owner)(struct file_lock *, struct file_lock *);
	void (*lm_put_owner)(struct file_lock *);
J
J. Bruce Fields 已提交
898
	void (*lm_notify)(struct file_lock *);	/* unblock callback */
899
	int (*lm_grant)(struct file_lock *, int);
J
Jeff Layton 已提交
900
	bool (*lm_break)(struct file_lock *);
901
	int (*lm_change)(struct file_lock *, int, struct list_head *);
902
	void (*lm_setup)(struct file_lock *, void **);
L
Linus Torvalds 已提交
903 904
};

905 906 907 908
struct lock_manager {
	struct list_head list;
};

909 910
struct net;
void locks_start_grace(struct net *, struct lock_manager *);
911
void locks_end_grace(struct lock_manager *);
912
int locks_in_grace(struct net *);
913

L
Linus Torvalds 已提交
914 915 916
/* that will die - we need it for nfs_lock_info */
#include <linux/nfs_fs_i.h>

917 918 919 920 921 922 923 924 925
/*
 * struct file_lock represents a generic "file lock". It's used to represent
 * POSIX byte range locks, BSD (flock) locks, and leases. It's important to
 * note that the same struct is used to represent both a request for a lock and
 * the lock itself, but the same object is never used for both.
 *
 * FIXME: should we create a separate "struct lock_request" to help distinguish
 * these two uses?
 *
926
 * The varous i_flctx lists are ordered by:
927
 *
928 929 930
 * 1) lock owner
 * 2) lock range start
 * 3) lock range end
931 932 933
 *
 * Obviously, the last two criteria only matter for POSIX locks.
 */
L
Linus Torvalds 已提交
934 935
struct file_lock {
	struct file_lock *fl_next;	/* singly linked list for this inode  */
936
	struct list_head fl_list;	/* link into file_lock_context */
937
	struct hlist_node fl_link;	/* node in global lists */
L
Linus Torvalds 已提交
938 939
	struct list_head fl_block;	/* circular list of blocked processes */
	fl_owner_t fl_owner;
940
	unsigned int fl_flags;
941
	unsigned char fl_type;
L
Linus Torvalds 已提交
942
	unsigned int fl_pid;
943
	int fl_link_cpu;		/* what cpu's list is this on? */
944
	struct pid *fl_nspid;
L
Linus Torvalds 已提交
945 946 947 948 949 950
	wait_queue_head_t fl_wait;
	struct file *fl_file;
	loff_t fl_start;
	loff_t fl_end;

	struct fasync_struct *	fl_fasync; /* for lease break notifications */
951 952 953
	/* for lease breaks: */
	unsigned long fl_break_time;
	unsigned long fl_downgrade_time;
L
Linus Torvalds 已提交
954

955
	const struct file_lock_operations *fl_ops;	/* Callbacks for filesystems */
956
	const struct lock_manager_operations *fl_lmops;	/* Callbacks for lockmanagers */
L
Linus Torvalds 已提交
957 958
	union {
		struct nfs_lock_info	nfs_fl;
959
		struct nfs4_lock_info	nfs4_fl;
D
David Howells 已提交
960 961 962 963
		struct {
			struct list_head link;	/* link in AFS vnode's pending_locks list */
			int state;		/* state of grant or error if -ve */
		} afs;
L
Linus Torvalds 已提交
964 965 966
	} fl_u;
};

967
struct file_lock_context {
968
	spinlock_t		flc_lock;
969
	struct list_head	flc_flock;
970
	struct list_head	flc_posix;
971
	struct list_head	flc_lease;
972 973
};

L
Linus Torvalds 已提交
974 975 976 977 978 979 980 981 982
/* The following constant reflects the upper bound of the file/locking space */
#ifndef OFFSET_MAX
#define INT_LIMIT(x)	(~((x)1 << (sizeof(x)*8 - 1)))
#define OFFSET_MAX	INT_LIMIT(loff_t)
#define OFFT_OFFSET_MAX	INT_LIMIT(off_t)
#endif

#include <linux/fcntl.h>

983 984 985
extern void send_sigio(struct fown_struct *fown, int fd, int band);

#ifdef CONFIG_FILE_LOCKING
986
extern int fcntl_getlk(struct file *, unsigned int, struct flock __user *);
987 988
extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
			struct flock __user *);
L
Linus Torvalds 已提交
989 990

#if BITS_PER_LONG == 32
991
extern int fcntl_getlk64(struct file *, unsigned int, struct flock64 __user *);
992 993
extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
			struct flock64 __user *);
L
Linus Torvalds 已提交
994 995 996 997 998 999
#endif

extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
extern int fcntl_getlease(struct file *filp);

/* fs/locks.c */
1000
void locks_free_lock_context(struct file_lock_context *ctx);
1001
void locks_free_lock(struct file_lock *fl);
L
Linus Torvalds 已提交
1002
extern void locks_init_lock(struct file_lock *);
1003
extern struct file_lock * locks_alloc_lock(void);
L
Linus Torvalds 已提交
1004
extern void locks_copy_lock(struct file_lock *, struct file_lock *);
1005
extern void locks_copy_conflock(struct file_lock *, struct file_lock *);
L
Linus Torvalds 已提交
1006
extern void locks_remove_posix(struct file *, fl_owner_t);
1007
extern void locks_remove_file(struct file *);
1008
extern void locks_release_private(struct file_lock *);
1009
extern void posix_test_lock(struct file *, struct file_lock *);
1010
extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
L
Linus Torvalds 已提交
1011
extern int posix_lock_file_wait(struct file *, struct file_lock *);
1012
extern int posix_unblock_lock(struct file_lock *);
1013
extern int vfs_test_lock(struct file *, struct file_lock *);
1014
extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
M
Marc Eshel 已提交
1015
extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
L
Linus Torvalds 已提交
1016
extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
J
J. Bruce Fields 已提交
1017
extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int type);
L
Linus Torvalds 已提交
1018
extern void lease_get_mtime(struct inode *, struct timespec *time);
1019 1020
extern int generic_setlease(struct file *, long, struct file_lock **, void **priv);
extern int vfs_setlease(struct file *, long, struct file_lock **, void **);
1021
extern int lease_modify(struct file_lock *, int, struct list_head *);
1022
#else /* !CONFIG_FILE_LOCKING */
1023 1024
static inline int fcntl_getlk(struct file *file, unsigned int cmd,
			      struct flock __user *user)
1025 1026 1027 1028 1029 1030 1031 1032 1033 1034
{
	return -EINVAL;
}

static inline int fcntl_setlk(unsigned int fd, struct file *file,
			      unsigned int cmd, struct flock __user *user)
{
	return -EACCES;
}

1035
#if BITS_PER_LONG == 32
1036 1037
static inline int fcntl_getlk64(struct file *file, unsigned int cmd,
				struct flock64 __user *user)
1038 1039 1040 1041 1042 1043 1044 1045 1046
{
	return -EINVAL;
}

static inline int fcntl_setlk64(unsigned int fd, struct file *file,
				unsigned int cmd, struct flock64 __user *user)
{
	return -EACCES;
}
1047
#endif
1048 1049
static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
{
1050
	return -EINVAL;
1051 1052 1053 1054
}

static inline int fcntl_getlease(struct file *filp)
{
1055
	return F_UNLCK;
1056 1057
}

1058 1059 1060 1061 1062
static inline void
locks_free_lock_context(struct file_lock_context *ctx)
{
}

1063 1064 1065 1066 1067
static inline void locks_init_lock(struct file_lock *fl)
{
	return;
}

1068
static inline void locks_copy_conflock(struct file_lock *new, struct file_lock *fl)
1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082
{
	return;
}

static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
{
	return;
}

static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
{
	return;
}

1083
static inline void locks_remove_file(struct file *filp)
1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103
{
	return;
}

static inline void posix_test_lock(struct file *filp, struct file_lock *fl)
{
	return;
}

static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
				  struct file_lock *conflock)
{
	return -ENOLCK;
}

static inline int posix_lock_file_wait(struct file *filp, struct file_lock *fl)
{
	return -ENOLCK;
}

1104
static inline int posix_unblock_lock(struct file_lock *waiter)
1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130
{
	return -ENOENT;
}

static inline int vfs_test_lock(struct file *filp, struct file_lock *fl)
{
	return 0;
}

static inline int vfs_lock_file(struct file *filp, unsigned int cmd,
				struct file_lock *fl, struct file_lock *conf)
{
	return -ENOLCK;
}

static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
{
	return 0;
}

static inline int flock_lock_file_wait(struct file *filp,
				       struct file_lock *request)
{
	return -ENOLCK;
}

J
J. Bruce Fields 已提交
1131
static inline int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
1132 1133 1134 1135 1136 1137 1138 1139 1140 1141
{
	return 0;
}

static inline void lease_get_mtime(struct inode *inode, struct timespec *time)
{
	return;
}

static inline int generic_setlease(struct file *filp, long arg,
1142
				    struct file_lock **flp, void **priv)
1143 1144 1145 1146 1147
{
	return -EINVAL;
}

static inline int vfs_setlease(struct file *filp, long arg,
1148
			       struct file_lock **lease, void **priv)
1149 1150 1151 1152
{
	return -EINVAL;
}

1153
static inline int lease_modify(struct file_lock *fl, int arg,
1154
			       struct list_head *dispose)
1155 1156 1157
{
	return -EINVAL;
}
1158 1159
#endif /* !CONFIG_FILE_LOCKING */

L
Linus Torvalds 已提交
1160 1161

struct fasync_struct {
1162 1163 1164 1165 1166 1167
	spinlock_t		fa_lock;
	int			magic;
	int			fa_fd;
	struct fasync_struct	*fa_next; /* singly linked list */
	struct file		*fa_file;
	struct rcu_head		fa_rcu;
L
Linus Torvalds 已提交
1168 1169 1170 1171 1172 1173
};

#define FASYNC_MAGIC 0x4601

/* SMP safe fasync helpers: */
extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1174 1175 1176 1177 1178
extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
extern int fasync_remove_entry(struct file *, struct fasync_struct **);
extern struct fasync_struct *fasync_alloc(void);
extern void fasync_free(struct fasync_struct *);

L
Linus Torvalds 已提交
1179 1180 1181
/* can be called from interrupts */
extern void kill_fasync(struct fasync_struct **, int, int);

1182 1183
extern void __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
extern void f_setown(struct file *filp, unsigned long arg, int force);
L
Linus Torvalds 已提交
1184
extern void f_delown(struct file *filp);
1185
extern pid_t f_getown(struct file *filp);
L
Linus Torvalds 已提交
1186 1187
extern int send_sigurg(struct fown_struct *fown);

1188 1189
struct mm_struct;

L
Linus Torvalds 已提交
1190 1191 1192 1193 1194 1195 1196
/*
 *	Umount options
 */

#define MNT_FORCE	0x00000001	/* Attempt to forcibily umount */
#define MNT_DETACH	0x00000002	/* Just detach from the tree */
#define MNT_EXPIRE	0x00000004	/* Mark for expiry */
1197 1198
#define UMOUNT_NOFOLLOW	0x00000008	/* Don't follow symlink on umount */
#define UMOUNT_UNUSED	0x80000000	/* Flag guaranteed to be unused */
L
Linus Torvalds 已提交
1199 1200


1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225
/* Possible states of 'frozen' field */
enum {
	SB_UNFROZEN = 0,		/* FS is unfrozen */
	SB_FREEZE_WRITE	= 1,		/* Writes, dir ops, ioctls frozen */
	SB_FREEZE_PAGEFAULT = 2,	/* Page faults stopped as well */
	SB_FREEZE_FS = 3,		/* For internal FS use (e.g. to stop
					 * internal threads if needed) */
	SB_FREEZE_COMPLETE = 4,		/* ->freeze_fs finished successfully */
};

#define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)

struct sb_writers {
	/* Counters for counting writers at each level */
	struct percpu_counter	counter[SB_FREEZE_LEVELS];
	wait_queue_head_t	wait;		/* queue for waiting for
						   writers / faults to finish */
	int			frozen;		/* Is sb frozen? */
	wait_queue_head_t	wait_unfrozen;	/* queue for waiting for
						   sb to be thawed */
#ifdef CONFIG_DEBUG_LOCK_ALLOC
	struct lockdep_map	lock_map[SB_FREEZE_LEVELS];
#endif
};

L
Linus Torvalds 已提交
1226 1227 1228
struct super_block {
	struct list_head	s_list;		/* Keep this first */
	dev_t			s_dev;		/* search index; _not_ kdev_t */
1229 1230
	unsigned char		s_blocksize_bits;
	unsigned long		s_blocksize;
1231
	loff_t			s_maxbytes;	/* Max file size */
L
Linus Torvalds 已提交
1232
	struct file_system_type	*s_type;
1233
	const struct super_operations	*s_op;
1234
	const struct dquot_operations	*dq_op;
1235
	const struct quotactl_ops	*s_qcop;
1236
	const struct export_operations *s_export_op;
L
Linus Torvalds 已提交
1237 1238 1239 1240 1241 1242
	unsigned long		s_flags;
	unsigned long		s_magic;
	struct dentry		*s_root;
	struct rw_semaphore	s_umount;
	int			s_count;
	atomic_t		s_active;
1243
#ifdef CONFIG_SECURITY
L
Linus Torvalds 已提交
1244
	void                    *s_security;
1245
#endif
1246
	const struct xattr_handler **s_xattr;
L
Linus Torvalds 已提交
1247 1248

	struct list_head	s_inodes;	/* all inodes */
1249
	struct hlist_bl_head	s_anon;		/* anonymous dentries for (nfs) exporting */
1250
	struct list_head	s_mounts;	/* list of mounts; _not_ for fs use */
L
Linus Torvalds 已提交
1251
	struct block_device	*s_bdev;
J
Jens Axboe 已提交
1252
	struct backing_dev_info *s_bdi;
1253
	struct mtd_info		*s_mtd;
A
Al Viro 已提交
1254
	struct hlist_node	s_instances;
1255
	unsigned int		s_quota_types;	/* Bitmask of supported quota types */
L
Linus Torvalds 已提交
1256 1257
	struct quota_info	s_dquot;	/* Diskquota specific options */

1258
	struct sb_writers	s_writers;
L
Linus Torvalds 已提交
1259 1260

	char s_id[32];				/* Informational name */
1261
	u8 s_uuid[16];				/* UUID */
L
Linus Torvalds 已提交
1262 1263

	void 			*s_fs_info;	/* Filesystem private info */
1264
	unsigned int		s_max_links;
1265
	fmode_t			s_mode;
L
Linus Torvalds 已提交
1266

1267 1268 1269 1270
	/* Granularity of c/m/atime in ns.
	   Cannot be worse than a second */
	u32		   s_time_gran;

L
Linus Torvalds 已提交
1271 1272 1273 1274
	/*
	 * The next field is for VFS *only*. No filesystems have any business
	 * even looking at it. You had been warned.
	 */
1275
	struct mutex s_vfs_rename_mutex;	/* Kludge */
L
Linus Torvalds 已提交
1276

M
Miklos Szeredi 已提交
1277 1278 1279 1280 1281
	/*
	 * Filesystem subtype.  If non-empty the filesystem type field
	 * in /proc/mounts will be "type.subtype"
	 */
	char *s_subtype;
1282 1283 1284 1285 1286

	/*
	 * Saved mount options for lazy filesystems using
	 * generic_show_options()
	 */
A
Arnd Bergmann 已提交
1287
	char __rcu *s_options;
A
Al Viro 已提交
1288
	const struct dentry_operations *s_d_op; /* default d_op for dentries */
1289 1290 1291 1292 1293

	/*
	 * Saved pool identifier for cleancache (-1 means none)
	 */
	int cleancache_poolid;
1294 1295

	struct shrinker s_shrink;	/* per-sb shrinker handle */
1296

M
Miklos Szeredi 已提交
1297 1298 1299
	/* Number of inodes with nlink == 0 but still referenced */
	atomic_long_t s_remove_count;

1300 1301
	/* Being remounted read-only */
	int s_readonly_remount;
1302 1303 1304

	/* AIO completions deferred from interrupt context */
	struct workqueue_struct *s_dio_done_wq;
A
Al Viro 已提交
1305
	struct hlist_head s_pins;
1306 1307 1308 1309 1310 1311 1312

	/*
	 * Keep the lru lists last in the structure so they always sit on their
	 * own individual cachelines.
	 */
	struct list_lru		s_dentry_lru ____cacheline_aligned_in_smp;
	struct list_lru		s_inode_lru ____cacheline_aligned_in_smp;
A
Al Viro 已提交
1313
	struct rcu_head		rcu;
1314 1315 1316 1317 1318

	/*
	 * Indicates how deep in a filesystem stack this SB is
	 */
	int s_stack_depth;
L
Linus Torvalds 已提交
1319 1320 1321 1322 1323 1324 1325 1326
};

extern struct timespec current_fs_time(struct super_block *sb);

/*
 * Snapshotting support.
 */

1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435
void __sb_end_write(struct super_block *sb, int level);
int __sb_start_write(struct super_block *sb, int level, bool wait);

/**
 * sb_end_write - drop write access to a superblock
 * @sb: the super we wrote to
 *
 * Decrement number of writers to the filesystem. Wake up possible waiters
 * wanting to freeze the filesystem.
 */
static inline void sb_end_write(struct super_block *sb)
{
	__sb_end_write(sb, SB_FREEZE_WRITE);
}

/**
 * sb_end_pagefault - drop write access to a superblock from a page fault
 * @sb: the super we wrote to
 *
 * Decrement number of processes handling write page fault to the filesystem.
 * Wake up possible waiters wanting to freeze the filesystem.
 */
static inline void sb_end_pagefault(struct super_block *sb)
{
	__sb_end_write(sb, SB_FREEZE_PAGEFAULT);
}

/**
 * sb_end_intwrite - drop write access to a superblock for internal fs purposes
 * @sb: the super we wrote to
 *
 * Decrement fs-internal number of writers to the filesystem.  Wake up possible
 * waiters wanting to freeze the filesystem.
 */
static inline void sb_end_intwrite(struct super_block *sb)
{
	__sb_end_write(sb, SB_FREEZE_FS);
}

/**
 * sb_start_write - get write access to a superblock
 * @sb: the super we write to
 *
 * When a process wants to write data or metadata to a file system (i.e. dirty
 * a page or an inode), it should embed the operation in a sb_start_write() -
 * sb_end_write() pair to get exclusion against file system freezing. This
 * function increments number of writers preventing freezing. If the file
 * system is already frozen, the function waits until the file system is
 * thawed.
 *
 * Since freeze protection behaves as a lock, users have to preserve
 * ordering of freeze protection and other filesystem locks. Generally,
 * freeze protection should be the outermost lock. In particular, we have:
 *
 * sb_start_write
 *   -> i_mutex			(write path, truncate, directory ops, ...)
 *   -> s_umount		(freeze_super, thaw_super)
 */
static inline void sb_start_write(struct super_block *sb)
{
	__sb_start_write(sb, SB_FREEZE_WRITE, true);
}

static inline int sb_start_write_trylock(struct super_block *sb)
{
	return __sb_start_write(sb, SB_FREEZE_WRITE, false);
}

/**
 * sb_start_pagefault - get write access to a superblock from a page fault
 * @sb: the super we write to
 *
 * When a process starts handling write page fault, it should embed the
 * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
 * exclusion against file system freezing. This is needed since the page fault
 * is going to dirty a page. This function increments number of running page
 * faults preventing freezing. If the file system is already frozen, the
 * function waits until the file system is thawed.
 *
 * Since page fault freeze protection behaves as a lock, users have to preserve
 * ordering of freeze protection and other filesystem locks. It is advised to
 * put sb_start_pagefault() close to mmap_sem in lock ordering. Page fault
 * handling code implies lock dependency:
 *
 * mmap_sem
 *   -> sb_start_pagefault
 */
static inline void sb_start_pagefault(struct super_block *sb)
{
	__sb_start_write(sb, SB_FREEZE_PAGEFAULT, true);
}

/*
 * sb_start_intwrite - get write access to a superblock for internal fs purposes
 * @sb: the super we write to
 *
 * This is the third level of protection against filesystem freezing. It is
 * free for use by a filesystem. The only requirement is that it must rank
 * below sb_start_pagefault.
 *
 * For example filesystem can call sb_start_intwrite() when starting a
 * transaction which somewhat eases handling of freezing for internal sources
 * of filesystem changes (internal fs threads, discarding preallocation on file
 * close, etc.).
 */
static inline void sb_start_intwrite(struct super_block *sb)
{
	__sb_start_write(sb, SB_FREEZE_FS, true);
}
L
Linus Torvalds 已提交
1436 1437


1438
extern bool inode_owner_or_capable(const struct inode *inode);
1439

L
Linus Torvalds 已提交
1440 1441 1442
/*
 * VFS helper functions..
 */
A
Al Viro 已提交
1443
extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
1444
extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
A
Al Viro 已提交
1445
extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
1446
extern int vfs_symlink(struct inode *, struct dentry *, const char *);
J
J. Bruce Fields 已提交
1447
extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
L
Linus Torvalds 已提交
1448
extern int vfs_rmdir(struct inode *, struct dentry *);
1449
extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
M
Miklos Szeredi 已提交
1450
extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
M
Miklos Szeredi 已提交
1451
extern int vfs_whiteout(struct inode *, struct dentry *);
L
Linus Torvalds 已提交
1452 1453 1454 1455 1456 1457

/*
 * VFS dentry helper functions.
 */
extern void dentry_unhash(struct dentry *dentry);

1458 1459 1460
/*
 * VFS file helper functions.
 */
1461
extern void inode_init_owner(struct inode *inode, const struct inode *dir,
A
Al Viro 已提交
1462
			umode_t mode);
M
Mark Fasheh 已提交
1463 1464 1465 1466 1467 1468 1469
/*
 * VFS FS_IOC_FIEMAP helper definitions.
 */
struct fiemap_extent_info {
	unsigned int fi_flags;		/* Flags as passed from user */
	unsigned int fi_extents_mapped;	/* Number of mapped extents */
	unsigned int fi_extents_max;	/* Size of fiemap_extent array */
1470 1471
	struct fiemap_extent __user *fi_extents_start; /* Start of
							fiemap_extent array */
M
Mark Fasheh 已提交
1472 1473 1474 1475 1476
};
int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
			    u64 phys, u64 len, u32 flags);
int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);

L
Linus Torvalds 已提交
1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498
/*
 * File types
 *
 * NOTE! These match bits 12..15 of stat.st_mode
 * (ie "(i_mode >> 12) & 15").
 */
#define DT_UNKNOWN	0
#define DT_FIFO		1
#define DT_CHR		2
#define DT_DIR		4
#define DT_BLK		6
#define DT_REG		8
#define DT_LNK		10
#define DT_SOCK		12
#define DT_WHT		14

/*
 * This is the "filldir" function type, used by readdir() to let
 * the kernel specify what kind of dirent layout it wants to have.
 * This allows the kernel to read directories into kernel space or
 * to have different dirent layouts depending on the binary type.
 */
1499 1500 1501 1502
struct dir_context;
typedef int (*filldir_t)(struct dir_context *, const char *, int, loff_t, u64,
			 unsigned);

1503
struct dir_context {
A
Al Viro 已提交
1504
	const filldir_t actor;
1505
	loff_t pos;
1506
};
1507

1508
struct block_device_operations;
L
Linus Torvalds 已提交
1509 1510 1511 1512 1513 1514 1515

/* These macros are for out of kernel modules to test that
 * the kernel supports the unlocked_ioctl and compat_ioctl
 * fields in struct file_operations. */
#define HAVE_COMPAT_IOCTL 1
#define HAVE_UNLOCKED_IOCTL 1

1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535
/*
 * These flags let !MMU mmap() govern direct device mapping vs immediate
 * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
 *
 * NOMMU_MAP_COPY:	Copy can be mapped (MAP_PRIVATE)
 * NOMMU_MAP_DIRECT:	Can be mapped directly (MAP_SHARED)
 * NOMMU_MAP_READ:	Can be mapped for reading
 * NOMMU_MAP_WRITE:	Can be mapped for writing
 * NOMMU_MAP_EXEC:	Can be mapped for execution
 */
#define NOMMU_MAP_COPY		0x00000001
#define NOMMU_MAP_DIRECT	0x00000008
#define NOMMU_MAP_READ		VM_MAYREAD
#define NOMMU_MAP_WRITE		VM_MAYWRITE
#define NOMMU_MAP_EXEC		VM_MAYEXEC

#define NOMMU_VMFLAGS \
	(NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)


1536 1537
struct iov_iter;

L
Linus Torvalds 已提交
1538 1539 1540 1541 1542
struct file_operations {
	struct module *owner;
	loff_t (*llseek) (struct file *, loff_t, int);
	ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
	ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1543 1544
	ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
	ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1545 1546
	ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
	ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
1547
	int (*iterate) (struct file *, struct dir_context *);
L
Linus Torvalds 已提交
1548 1549 1550 1551
	unsigned int (*poll) (struct file *, struct poll_table_struct *);
	long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
	long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
	int (*mmap) (struct file *, struct vm_area_struct *);
A
Al Viro 已提交
1552
	int (*mremap)(struct file *, struct vm_area_struct *);
L
Linus Torvalds 已提交
1553
	int (*open) (struct inode *, struct file *);
1554
	int (*flush) (struct file *, fl_owner_t id);
L
Linus Torvalds 已提交
1555
	int (*release) (struct inode *, struct file *);
1556
	int (*fsync) (struct file *, loff_t, loff_t, int datasync);
L
Linus Torvalds 已提交
1557 1558 1559 1560 1561 1562 1563
	int (*aio_fsync) (struct kiocb *, int datasync);
	int (*fasync) (int, struct file *, int);
	int (*lock) (struct file *, int, struct file_lock *);
	ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
	unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
	int (*check_flags)(int);
	int (*flock) (struct file *, int, struct file_lock *);
1564 1565
	ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
	ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1566
	int (*setlease)(struct file *, long, struct file_lock **, void **);
1567 1568
	long (*fallocate)(struct file *file, int mode, loff_t offset,
			  loff_t len);
1569
	void (*show_fdinfo)(struct seq_file *m, struct file *f);
1570 1571 1572
#ifndef CONFIG_MMU
	unsigned (*mmap_capabilities)(struct file *);
#endif
L
Linus Torvalds 已提交
1573 1574 1575
};

struct inode_operations {
A
Al Viro 已提交
1576
	struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
1577
	void * (*follow_link) (struct dentry *, struct nameidata *);
1578
	int (*permission) (struct inode *, int);
1579
	struct posix_acl * (*get_acl)(struct inode *, int);
1580 1581 1582 1583

	int (*readlink) (struct dentry *, char __user *,int);
	void (*put_link) (struct dentry *, struct nameidata *, void *);

A
Al Viro 已提交
1584
	int (*create) (struct inode *,struct dentry *, umode_t, bool);
L
Linus Torvalds 已提交
1585 1586 1587
	int (*link) (struct dentry *,struct inode *,struct dentry *);
	int (*unlink) (struct inode *,struct dentry *);
	int (*symlink) (struct inode *,struct dentry *,const char *);
1588
	int (*mkdir) (struct inode *,struct dentry *,umode_t);
L
Linus Torvalds 已提交
1589
	int (*rmdir) (struct inode *,struct dentry *);
A
Al Viro 已提交
1590
	int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
L
Linus Torvalds 已提交
1591 1592
	int (*rename) (struct inode *, struct dentry *,
			struct inode *, struct dentry *);
M
Miklos Szeredi 已提交
1593 1594
	int (*rename2) (struct inode *, struct dentry *,
			struct inode *, struct dentry *, unsigned int);
L
Linus Torvalds 已提交
1595 1596 1597 1598 1599 1600
	int (*setattr) (struct dentry *, struct iattr *);
	int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
	int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
	ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
	ssize_t (*listxattr) (struct dentry *, char *, size_t);
	int (*removexattr) (struct dentry *, const char *);
M
Mark Fasheh 已提交
1601 1602
	int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
		      u64 len);
1603
	int (*update_time)(struct inode *, struct timespec *, int);
A
Al Viro 已提交
1604
	int (*atomic_open)(struct inode *, struct dentry *,
A
Al Viro 已提交
1605
			   struct file *, unsigned open_flag,
A
Al Viro 已提交
1606
			   umode_t create_mode, int *opened);
1607
	int (*tmpfile) (struct inode *, struct dentry *, umode_t);
1608
	int (*set_acl)(struct inode *, struct posix_acl *, int);
M
Miklos Szeredi 已提交
1609 1610 1611

	/* WARNING: probably going away soon, do not use! */
	int (*dentry_open)(struct dentry *, struct file *, const struct cred *);
1612
} ____cacheline_aligned;
L
Linus Torvalds 已提交
1613

B
Badari Pulavarty 已提交
1614
ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
C
Christopher Yeoh 已提交
1615 1616
			      unsigned long nr_segs, unsigned long fast_segs,
			      struct iovec *fast_pointer,
1617
			      struct iovec **ret_pointer);
B
Badari Pulavarty 已提交
1618

D
Dmitry Kasatkin 已提交
1619
extern ssize_t __vfs_read(struct file *, char __user *, size_t, loff_t *);
L
Linus Torvalds 已提交
1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630
extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
		unsigned long, loff_t *);
extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
		unsigned long, loff_t *);

struct super_operations {
   	struct inode *(*alloc_inode)(struct super_block *sb);
	void (*destroy_inode)(struct inode *);

1631
   	void (*dirty_inode) (struct inode *, int flags);
1632
	int (*write_inode) (struct inode *, struct writeback_control *wbc);
1633
	int (*drop_inode) (struct inode *);
A
Al Viro 已提交
1634
	void (*evict_inode) (struct inode *);
L
Linus Torvalds 已提交
1635 1636
	void (*put_super) (struct super_block *);
	int (*sync_fs)(struct super_block *sb, int wait);
1637
	int (*freeze_super) (struct super_block *);
1638
	int (*freeze_fs) (struct super_block *);
1639
	int (*thaw_super) (struct super_block *);
1640
	int (*unfreeze_fs) (struct super_block *);
1641
	int (*statfs) (struct dentry *, struct kstatfs *);
L
Linus Torvalds 已提交
1642
	int (*remount_fs) (struct super_block *, int *, char *);
1643
	void (*umount_begin) (struct super_block *);
L
Linus Torvalds 已提交
1644

1645
	int (*show_options)(struct seq_file *, struct dentry *);
1646
	int (*show_devname)(struct seq_file *, struct dentry *);
1647
	int (*show_path)(struct seq_file *, struct dentry *);
1648
	int (*show_stats)(struct seq_file *, struct dentry *);
1649
#ifdef CONFIG_QUOTA
L
Linus Torvalds 已提交
1650 1651
	ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
	ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1652
	struct dquot **(*get_dquots)(struct inode *);
1653
#endif
1654
	int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
1655 1656 1657 1658
	long (*nr_cached_objects)(struct super_block *,
				  struct shrink_control *);
	long (*free_cached_objects)(struct super_block *,
				    struct shrink_control *);
L
Linus Torvalds 已提交
1659 1660
};

D
David Howells 已提交
1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676
/*
 * Inode flags - they have no relation to superblock flags now
 */
#define S_SYNC		1	/* Writes are synced at once */
#define S_NOATIME	2	/* Do not update access times */
#define S_APPEND	4	/* Append-only file */
#define S_IMMUTABLE	8	/* Immutable file */
#define S_DEAD		16	/* removed, but still open directory */
#define S_NOQUOTA	32	/* Inode is not counted to quota */
#define S_DIRSYNC	64	/* Directory modifications are synchronous */
#define S_NOCMTIME	128	/* Do not update file c/mtime */
#define S_SWAPFILE	256	/* Do not truncate: swapon got its bmaps */
#define S_PRIVATE	512	/* Inode is fs-internal */
#define S_IMA		1024	/* Inode has an associated IMA struct */
#define S_AUTOMOUNT	2048	/* Automount/referral quasi-directory */
#define S_NOSEC		4096	/* no suid or xattr security attributes */
1677
#ifdef CONFIG_FS_DAX
1678 1679 1680 1681
#define S_DAX		8192	/* Direct Access, avoiding the page cache */
#else
#define S_DAX		0	/* Make all the DAX code disappear */
#endif
D
David Howells 已提交
1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718

/*
 * Note that nosuid etc flags are inode-specific: setting some file-system
 * flags just means all the inodes inherit those flags by default. It might be
 * possible to override it selectively if you really wanted to with some
 * ioctl() that is not currently implemented.
 *
 * Exception: MS_RDONLY is always applied to the entire file system.
 *
 * Unfortunately, it is possible to change a filesystems flags with it mounted
 * with files in use.  This means that all of the inodes will not have their
 * i_flags updated.  Hence, i_flags no longer inherit the superblock mount
 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
 */
#define __IS_FLG(inode, flg)	((inode)->i_sb->s_flags & (flg))

#define IS_RDONLY(inode)	((inode)->i_sb->s_flags & MS_RDONLY)
#define IS_SYNC(inode)		(__IS_FLG(inode, MS_SYNCHRONOUS) || \
					((inode)->i_flags & S_SYNC))
#define IS_DIRSYNC(inode)	(__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
					((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
#define IS_MANDLOCK(inode)	__IS_FLG(inode, MS_MANDLOCK)
#define IS_NOATIME(inode)	__IS_FLG(inode, MS_RDONLY|MS_NOATIME)
#define IS_I_VERSION(inode)	__IS_FLG(inode, MS_I_VERSION)

#define IS_NOQUOTA(inode)	((inode)->i_flags & S_NOQUOTA)
#define IS_APPEND(inode)	((inode)->i_flags & S_APPEND)
#define IS_IMMUTABLE(inode)	((inode)->i_flags & S_IMMUTABLE)
#define IS_POSIXACL(inode)	__IS_FLG(inode, MS_POSIXACL)

#define IS_DEADDIR(inode)	((inode)->i_flags & S_DEAD)
#define IS_NOCMTIME(inode)	((inode)->i_flags & S_NOCMTIME)
#define IS_SWAPFILE(inode)	((inode)->i_flags & S_SWAPFILE)
#define IS_PRIVATE(inode)	((inode)->i_flags & S_PRIVATE)
#define IS_IMA(inode)		((inode)->i_flags & S_IMA)
#define IS_AUTOMOUNT(inode)	((inode)->i_flags & S_AUTOMOUNT)
#define IS_NOSEC(inode)		((inode)->i_flags & S_NOSEC)
1719
#define IS_DAX(inode)		((inode)->i_flags & S_DAX)
D
David Howells 已提交
1720

M
Miklos Szeredi 已提交
1721 1722 1723
#define IS_WHITEOUT(inode)	(S_ISCHR(inode->i_mode) && \
				 (inode)->i_rdev == WHITEOUT_DEV)

J
Joern Engel 已提交
1724
/*
1725
 * Inode state bits.  Protected by inode->i_lock
J
Joern Engel 已提交
1726 1727 1728 1729 1730 1731 1732 1733
 *
 * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
 * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
 *
 * Four bits define the lifetime of an inode.  Initially, inodes are I_NEW,
 * until that flag is cleared.  I_WILL_FREE, I_FREEING and I_CLEAR are set at
 * various stages of removing an inode.
 *
C
Christoph Hellwig 已提交
1734
 * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
J
Joern Engel 已提交
1735
 *
J
Joern Engel 已提交
1736 1737
 * I_DIRTY_SYNC		Inode is dirty, but doesn't have to be written on
 *			fdatasync().  i_atime is the usual cause.
1738 1739 1740 1741
 * I_DIRTY_DATASYNC	Data-related inode changes pending. We keep track of
 *			these changes separately from I_DIRTY_SYNC so that we
 *			don't have to write inode on fdatasync() when only
 *			mtime has changed in it.
J
Joern Engel 已提交
1742
 * I_DIRTY_PAGES	Inode has dirty pages.  Inode itself may be clean.
C
Christoph Hellwig 已提交
1743 1744 1745 1746 1747 1748 1749 1750
 * I_NEW		Serves as both a mutex and completion notification.
 *			New inodes set I_NEW.  If two processes both create
 *			the same inode, one of them will release its inode and
 *			wait for I_NEW to be released before returning.
 *			Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
 *			also cause waiting on I_NEW, without I_NEW actually
 *			being set.  find_inode() uses this to prevent returning
 *			nearly-dead inodes.
J
Joern Engel 已提交
1751 1752 1753 1754 1755 1756
 * I_WILL_FREE		Must be set when calling write_inode_now() if i_count
 *			is zero.  I_FREEING must be set when I_WILL_FREE is
 *			cleared.
 * I_FREEING		Set when inode is about to be freed but still has dirty
 *			pages or buffers attached or the inode itself is still
 *			dirty.
1757 1758
 * I_CLEAR		Added by clear_inode().  In this state the inode is
 *			clean and can be destroyed.  Inode keeps I_FREEING.
J
Joern Engel 已提交
1759 1760 1761 1762 1763
 *
 *			Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
 *			prohibited for many purposes.  iget() must wait for
 *			the inode to be completely released, then create it
 *			anew.  Other functions will just ignore such inodes,
C
Christoph Hellwig 已提交
1764
 *			if appropriate.  I_NEW is used for waiting.
J
Joern Engel 已提交
1765
 *
1766 1767 1768 1769
 * I_SYNC		Writeback of inode is running. The bit is set during
 *			data writeback, and cleared with a wakeup on the bit
 *			address once it is done. The bit is also used to pin
 *			the inode in memory for flusher thread.
J
Joern Engel 已提交
1770
 *
C
Christoph Hellwig 已提交
1771 1772 1773 1774
 * I_REFERENCED		Marks the inode as recently references on the LRU list.
 *
 * I_DIO_WAKEUP		Never set.  Only used as a key for wait_on_bit().
 *
J
Joern Engel 已提交
1775 1776
 * Q: What is the difference between I_WILL_FREE and I_FREEING?
 */
1777 1778 1779
#define I_DIRTY_SYNC		(1 << 0)
#define I_DIRTY_DATASYNC	(1 << 1)
#define I_DIRTY_PAGES		(1 << 2)
C
Christoph Hellwig 已提交
1780 1781
#define __I_NEW			3
#define I_NEW			(1 << __I_NEW)
1782 1783 1784
#define I_WILL_FREE		(1 << 4)
#define I_FREEING		(1 << 5)
#define I_CLEAR			(1 << 6)
C
Christoph Hellwig 已提交
1785
#define __I_SYNC		7
J
Joern Engel 已提交
1786
#define I_SYNC			(1 << __I_SYNC)
1787
#define I_REFERENCED		(1 << 8)
C
Christoph Hellwig 已提交
1788 1789
#define __I_DIO_WAKEUP		9
#define I_DIO_WAKEUP		(1 << I_DIO_WAKEUP)
1790
#define I_LINKABLE		(1 << 10)
1791 1792 1793
#define I_DIRTY_TIME		(1 << 11)
#define __I_DIRTY_TIME_EXPIRED	12
#define I_DIRTY_TIME_EXPIRED	(1 << __I_DIRTY_TIME_EXPIRED)
L
Linus Torvalds 已提交
1794 1795

#define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1796
#define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
L
Linus Torvalds 已提交
1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808

extern void __mark_inode_dirty(struct inode *, int);
static inline void mark_inode_dirty(struct inode *inode)
{
	__mark_inode_dirty(inode, I_DIRTY);
}

static inline void mark_inode_dirty_sync(struct inode *inode)
{
	__mark_inode_dirty(inode, I_DIRTY_SYNC);
}

M
Miklos Szeredi 已提交
1809 1810 1811 1812
extern void inc_nlink(struct inode *inode);
extern void drop_nlink(struct inode *inode);
extern void clear_nlink(struct inode *inode);
extern void set_nlink(struct inode *inode, unsigned int nlink);
1813 1814 1815 1816

static inline void inode_inc_link_count(struct inode *inode)
{
	inc_nlink(inode);
1817 1818 1819
	mark_inode_dirty(inode);
}

1820 1821 1822
static inline void inode_dec_link_count(struct inode *inode)
{
	drop_nlink(inode);
1823 1824 1825
	mark_inode_dirty(inode);
}

1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840
/**
 * inode_inc_iversion - increments i_version
 * @inode: inode that need to be updated
 *
 * Every time the inode is modified, the i_version field will be incremented.
 * The filesystem has to be mounted with i_version flag
 */

static inline void inode_inc_iversion(struct inode *inode)
{
       spin_lock(&inode->i_lock);
       inode->i_version++;
       spin_unlock(&inode->i_lock);
}

1841 1842 1843 1844 1845 1846 1847
enum file_time_flags {
	S_ATIME = 1,
	S_MTIME = 2,
	S_CTIME = 4,
	S_VERSION = 8,
};

A
Al Viro 已提交
1848
extern void touch_atime(const struct path *);
L
Linus Torvalds 已提交
1849 1850 1851
static inline void file_accessed(struct file *file)
{
	if (!(file->f_flags & O_NOATIME))
A
Al Viro 已提交
1852
		touch_atime(&file->f_path);
L
Linus Torvalds 已提交
1853 1854 1855
}

int sync_inode(struct inode *inode, struct writeback_control *wbc);
C
Christoph Hellwig 已提交
1856
int sync_inode_metadata(struct inode *inode, int wait);
L
Linus Torvalds 已提交
1857 1858 1859 1860

struct file_system_type {
	const char *name;
	int fs_flags;
D
David Howells 已提交
1861 1862 1863
#define FS_REQUIRES_DEV		1 
#define FS_BINARY_MOUNTDATA	2
#define FS_HAS_SUBTYPE		4
1864 1865
#define FS_USERNS_MOUNT		8	/* Can be mounted by userns root */
#define FS_USERNS_DEV_MOUNT	16 /* A userns mount does not imply MNT_NODEV */
D
David Howells 已提交
1866
#define FS_RENAME_DOES_D_MOVE	32768	/* FS will handle d_move() during rename() internally. */
A
Al Viro 已提交
1867 1868
	struct dentry *(*mount) (struct file_system_type *, int,
		       const char *, void *);
L
Linus Torvalds 已提交
1869 1870 1871
	void (*kill_sb) (struct super_block *);
	struct module *owner;
	struct file_system_type * next;
A
Al Viro 已提交
1872
	struct hlist_head fs_supers;
1873

I
Ingo Molnar 已提交
1874
	struct lock_class_key s_lock_key;
1875
	struct lock_class_key s_umount_key;
1876
	struct lock_class_key s_vfs_rename_key;
1877
	struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
1878 1879 1880

	struct lock_class_key i_lock_key;
	struct lock_class_key i_mutex_key;
1881
	struct lock_class_key i_mutex_dir_key;
L
Linus Torvalds 已提交
1882 1883
};

1884 1885
#define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)

A
Al Viro 已提交
1886 1887
extern struct dentry *mount_ns(struct file_system_type *fs_type, int flags,
	void *data, int (*fill_super)(struct super_block *, void *, int));
A
Al Viro 已提交
1888 1889 1890
extern struct dentry *mount_bdev(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data,
	int (*fill_super)(struct super_block *, void *, int));
A
Al Viro 已提交
1891 1892 1893
extern struct dentry *mount_single(struct file_system_type *fs_type,
	int flags, void *data,
	int (*fill_super)(struct super_block *, void *, int));
A
Al Viro 已提交
1894 1895 1896
extern struct dentry *mount_nodev(struct file_system_type *fs_type,
	int flags, void *data,
	int (*fill_super)(struct super_block *, void *, int));
A
Al Viro 已提交
1897
extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
L
Linus Torvalds 已提交
1898 1899 1900 1901 1902
void generic_shutdown_super(struct super_block *sb);
void kill_block_super(struct super_block *sb);
void kill_anon_super(struct super_block *sb);
void kill_litter_super(struct super_block *sb);
void deactivate_super(struct super_block *sb);
A
Al Viro 已提交
1903
void deactivate_locked_super(struct super_block *sb);
L
Linus Torvalds 已提交
1904
int set_anon_super(struct super_block *s, void *data);
1905 1906
int get_anon_bdev(dev_t *);
void free_anon_bdev(dev_t);
L
Linus Torvalds 已提交
1907 1908 1909
struct super_block *sget(struct file_system_type *type,
			int (*test)(struct super_block *,void *),
			int (*set)(struct super_block *,void *),
D
David Howells 已提交
1910
			int flags, void *data);
A
Al Viro 已提交
1911
extern struct dentry *mount_pseudo(struct file_system_type *, char *,
1912 1913 1914
	const struct super_operations *ops,
	const struct dentry_operations *dops,
	unsigned long);
L
Linus Torvalds 已提交
1915 1916 1917 1918 1919 1920

/* Alas, no aliases. Too much hassle with bringing module.h everywhere */
#define fops_get(fops) \
	(((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
#define fops_put(fops) \
	do { if (fops) module_put((fops)->owner); } while(0)
1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931
/*
 * This one is to be used *ONLY* from ->open() instances.
 * fops must be non-NULL, pinned down *and* module dependencies
 * should be sufficient to pin the caller down as well.
 */
#define replace_fops(f, fops) \
	do {	\
		struct file *__file = (f); \
		fops_put(__file->f_op); \
		BUG_ON(!(__file->f_op = (fops))); \
	} while(0)
L
Linus Torvalds 已提交
1932 1933 1934

extern int register_filesystem(struct file_system_type *);
extern int unregister_filesystem(struct file_system_type *);
1935 1936
extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
#define kern_mount(type) kern_mount_data(type, NULL)
1937
extern void kern_unmount(struct vfsmount *mnt);
L
Linus Torvalds 已提交
1938 1939
extern int may_umount_tree(struct vfsmount *);
extern int may_umount(struct vfsmount *);
1940 1941
extern long do_mount(const char *, const char __user *,
		     const char *, unsigned long, void *);
A
Al Viro 已提交
1942
extern struct vfsmount *collect_mounts(struct path *);
1943
extern void drop_collected_mounts(struct vfsmount *);
A
Al Viro 已提交
1944 1945
extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
			  struct vfsmount *);
1946
extern int vfs_statfs(struct path *, struct kstatfs *);
A
Al Viro 已提交
1947 1948
extern int user_statfs(const char __user *, struct kstatfs *);
extern int fd_statfs(int, struct kstatfs *);
A
Al Viro 已提交
1949
extern int vfs_ustat(dev_t, struct kstatfs *);
1950 1951
extern int freeze_super(struct super_block *super);
extern int thaw_super(struct super_block *super);
1952
extern bool our_mnt(struct vfsmount *mnt);
1953
extern bool fs_fully_visible(struct file_system_type *);
L
Linus Torvalds 已提交
1954

A
Al Viro 已提交
1955 1956
extern int current_umask(void);

1957 1958
extern void ihold(struct inode * inode);
extern void iput(struct inode *);
1959
extern int generic_update_time(struct inode *, struct timespec *, int);
1960

A
Al Viro 已提交
1961
static inline struct inode *file_inode(const struct file *f)
1962 1963 1964 1965
{
	return f->f_inode;
}

M
Miklos Szeredi 已提交
1966
/* /sys/fs */
1967
extern struct kobject *fs_kobj;
M
Miklos Szeredi 已提交
1968

1969
#define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK)
1970

L
Linus Torvalds 已提交
1971 1972 1973
#define FLOCK_VERIFY_READ  1
#define FLOCK_VERIFY_WRITE 2

1974
#ifdef CONFIG_FILE_LOCKING
1975
extern int locks_mandatory_locked(struct file *);
L
Linus Torvalds 已提交
1976 1977 1978 1979 1980 1981
extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);

/*
 * Candidates for mandatory locking have the setgid bit set
 * but no group execute bit -  an otherwise meaningless combination.
 */
1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996

static inline int __mandatory_lock(struct inode *ino)
{
	return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
}

/*
 * ... and these candidates should be on MS_MANDLOCK mounted fs,
 * otherwise these will be advisory locks
 */

static inline int mandatory_lock(struct inode *ino)
{
	return IS_MANDLOCK(ino) && __mandatory_lock(ino);
}
L
Linus Torvalds 已提交
1997

1998
static inline int locks_verify_locked(struct file *file)
L
Linus Torvalds 已提交
1999
{
2000 2001
	if (mandatory_lock(file_inode(file)))
		return locks_mandatory_locked(file);
L
Linus Torvalds 已提交
2002 2003 2004 2005 2006 2007 2008
	return 0;
}

static inline int locks_verify_truncate(struct inode *inode,
				    struct file *filp,
				    loff_t size)
{
2009
	if (inode->i_flctx && mandatory_lock(inode))
L
Linus Torvalds 已提交
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
		return locks_mandatory_area(
			FLOCK_VERIFY_WRITE, inode, filp,
			size < inode->i_size ? size : inode->i_size,
			(size < inode->i_size ? inode->i_size - size
			 : size - inode->i_size)
		);
	return 0;
}

static inline int break_lease(struct inode *inode, unsigned int mode)
{
2021 2022
	/*
	 * Since this check is lockless, we must ensure that any refcounts
2023 2024 2025
	 * taken are done before checking i_flctx->flc_lease. Otherwise, we
	 * could end up racing with tasks trying to set a new lease on this
	 * file.
2026 2027
	 */
	smp_mb();
2028
	if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
J
J. Bruce Fields 已提交
2029
		return __break_lease(inode, mode, FL_LEASE);
L
Linus Torvalds 已提交
2030 2031
	return 0;
}
J
J. Bruce Fields 已提交
2032 2033 2034

static inline int break_deleg(struct inode *inode, unsigned int mode)
{
2035 2036
	/*
	 * Since this check is lockless, we must ensure that any refcounts
2037 2038 2039
	 * taken are done before checking i_flctx->flc_lease. Otherwise, we
	 * could end up racing with tasks trying to set a new lease on this
	 * file.
2040 2041
	 */
	smp_mb();
2042
	if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
J
J. Bruce Fields 已提交
2043
		return __break_lease(inode, mode, FL_DELEG);
L
Linus Torvalds 已提交
2044 2045
	return 0;
}
J
J. Bruce Fields 已提交
2046

2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068
static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
{
	int ret;

	ret = break_deleg(inode, O_WRONLY|O_NONBLOCK);
	if (ret == -EWOULDBLOCK && delegated_inode) {
		*delegated_inode = inode;
		ihold(inode);
	}
	return ret;
}

static inline int break_deleg_wait(struct inode **delegated_inode)
{
	int ret;

	ret = break_deleg(*delegated_inode, O_WRONLY);
	iput(*delegated_inode);
	*delegated_inode = NULL;
	return ret;
}

C
Christoph Hellwig 已提交
2069 2070 2071 2072 2073 2074 2075 2076 2077 2078
static inline int break_layout(struct inode *inode, bool wait)
{
	smp_mb();
	if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
		return __break_lease(inode,
				wait ? O_WRONLY : O_WRONLY | O_NONBLOCK,
				FL_LAYOUT);
	return 0;
}

2079
#else /* !CONFIG_FILE_LOCKING */
2080
static inline int locks_mandatory_locked(struct file *file)
2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101
{
	return 0;
}

static inline int locks_mandatory_area(int rw, struct inode *inode,
				       struct file *filp, loff_t offset,
				       size_t count)
{
	return 0;
}

static inline int __mandatory_lock(struct inode *inode)
{
	return 0;
}

static inline int mandatory_lock(struct inode *inode)
{
	return 0;
}

2102
static inline int locks_verify_locked(struct file *file)
2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117
{
	return 0;
}

static inline int locks_verify_truncate(struct inode *inode, struct file *filp,
					size_t size)
{
	return 0;
}

static inline int break_lease(struct inode *inode, unsigned int mode)
{
	return 0;
}

J
J. Bruce Fields 已提交
2118 2119 2120 2121
static inline int break_deleg(struct inode *inode, unsigned int mode)
{
	return 0;
}
2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133

static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
{
	return 0;
}

static inline int break_deleg_wait(struct inode **delegated_inode)
{
	BUG();
	return 0;
}

C
Christoph Hellwig 已提交
2134 2135 2136 2137 2138
static inline int break_layout(struct inode *inode, bool wait)
{
	return 0;
}

2139
#endif /* CONFIG_FILE_LOCKING */
L
Linus Torvalds 已提交
2140 2141

/* fs/open.c */
2142
struct audit_names;
2143
struct filename {
2144 2145 2146
	const char		*name;	/* pointer to actual string */
	const __user char	*uptr;	/* original userland pointer */
	struct audit_names	*aname;
2147
	int			refcnt;
2148
	bool			separate; /* should "name" be freed? */
2149
};
L
Linus Torvalds 已提交
2150

2151
extern long vfs_truncate(struct path *, loff_t);
2152 2153
extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
		       struct file *filp);
2154
extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
2155
			loff_t len);
J
Jason Uhlenkott 已提交
2156
extern long do_sys_open(int dfd, const char __user *filename, int flags,
2157
			umode_t mode);
2158
extern struct file *file_open_name(struct filename *, int, umode_t);
2159
extern struct file *filp_open(const char *, int, umode_t);
A
Al Viro 已提交
2160 2161
extern struct file *file_open_root(struct dentry *, struct vfsmount *,
				   const char *, int);
M
Miklos Szeredi 已提交
2162
extern int vfs_open(const struct path *, struct file *, const struct cred *);
2163
extern struct file * dentry_open(const struct path *, int, const struct cred *);
L
Linus Torvalds 已提交
2164
extern int filp_close(struct file *, fl_owner_t id);
2165

2166
extern struct filename *getname_flags(const char __user *, int, int *);
2167
extern struct filename *getname(const char __user *);
2168
extern struct filename *getname_kernel(const char *);
2169
extern void putname(struct filename *name);
2170

2171 2172 2173 2174
enum {
	FILE_CREATED = 1,
	FILE_OPENED = 2
};
A
Al Viro 已提交
2175 2176 2177
extern int finish_open(struct file *file, struct dentry *dentry,
			int (*open)(struct inode *, struct file *),
			int *opened);
A
Al Viro 已提交
2178
extern int finish_no_open(struct file *file, struct dentry *dentry);
L
Linus Torvalds 已提交
2179

2180 2181 2182 2183
/* fs/ioctl.c */

extern int ioctl_preallocate(struct file *filp, void __user *argp);

L
Linus Torvalds 已提交
2184 2185 2186 2187
/* fs/dcache.c */
extern void __init vfs_caches_init_early(void);
extern void __init vfs_caches_init(unsigned long);

2188 2189
extern struct kmem_cache *names_cachep;

2190
#define __getname()		kmem_cache_alloc(names_cachep, GFP_KERNEL)
V
Vegard Nossum 已提交
2191
#define __putname(name)		kmem_cache_free(names_cachep, (void *)(name))
L
Linus Torvalds 已提交
2192

2193
#ifdef CONFIG_BLOCK
L
Linus Torvalds 已提交
2194
extern int register_blkdev(unsigned int, const char *);
A
Akinobu Mita 已提交
2195
extern void unregister_blkdev(unsigned int, const char *);
L
Linus Torvalds 已提交
2196
extern struct block_device *bdget(dev_t);
2197
extern struct block_device *bdgrab(struct block_device *bdev);
L
Linus Torvalds 已提交
2198 2199 2200
extern void bd_set_size(struct block_device *, loff_t size);
extern void bd_forget(struct inode *inode);
extern void bdput(struct block_device *);
N
Nick Piggin 已提交
2201
extern void invalidate_bdev(struct block_device *);
2202
extern void iterate_bdevs(void (*)(struct block_device *, void *), void *);
N
Nick Piggin 已提交
2203
extern int sync_blockdev(struct block_device *bdev);
A
Al Viro 已提交
2204
extern void kill_bdev(struct block_device *);
N
Nick Piggin 已提交
2205
extern struct super_block *freeze_bdev(struct block_device *);
2206
extern void emergency_thaw_all(void);
N
Nick Piggin 已提交
2207 2208
extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
extern int fsync_bdev(struct block_device *);
2209
extern int sb_is_blkdev_sb(struct super_block *sb);
2210 2211
#else
static inline void bd_forget(struct inode *inode) {}
2212
static inline int sync_blockdev(struct block_device *bdev) { return 0; }
A
Al Viro 已提交
2213
static inline void kill_bdev(struct block_device *bdev) {}
2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224
static inline void invalidate_bdev(struct block_device *bdev) {}

static inline struct super_block *freeze_bdev(struct block_device *sb)
{
	return NULL;
}

static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
{
	return 0;
}
2225 2226 2227 2228

static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg)
{
}
2229 2230 2231 2232 2233

static inline int sb_is_blkdev_sb(struct super_block *sb)
{
	return 0;
}
2234
#endif
2235
extern int sync_filesystem(struct super_block *);
2236
extern const struct file_operations def_blk_fops;
2237
extern const struct file_operations def_chr_fops;
2238
#ifdef CONFIG_BLOCK
L
Linus Torvalds 已提交
2239
extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
2240
extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long);
L
Linus Torvalds 已提交
2241
extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
2242
extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
2243 2244 2245 2246
extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
					       void *holder);
extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
					      void *holder);
A
Al Viro 已提交
2247
extern void blkdev_put(struct block_device *bdev, fmode_t mode);
2248
#ifdef CONFIG_SYSFS
2249
extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
2250 2251
extern void bd_unlink_disk_holder(struct block_device *bdev,
				  struct gendisk *disk);
2252
#else
2253 2254 2255 2256 2257
static inline int bd_link_disk_holder(struct block_device *bdev,
				      struct gendisk *disk)
{
	return 0;
}
2258 2259 2260 2261
static inline void bd_unlink_disk_holder(struct block_device *bdev,
					 struct gendisk *disk)
{
}
2262
#endif
2263
#endif
L
Linus Torvalds 已提交
2264 2265

/* fs/char_dev.c */
2266
#define CHRDEV_MAJOR_HASH_SIZE	255
L
Linus Torvalds 已提交
2267 2268
extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
extern int register_chrdev_region(dev_t, unsigned, const char *);
2269 2270 2271 2272 2273
extern int __register_chrdev(unsigned int major, unsigned int baseminor,
			     unsigned int count, const char *name,
			     const struct file_operations *fops);
extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
				unsigned int count, const char *name);
L
Linus Torvalds 已提交
2274
extern void unregister_chrdev_region(dev_t, unsigned);
2275
extern void chrdev_show(struct seq_file *,off_t);
L
Linus Torvalds 已提交
2276

2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287
static inline int register_chrdev(unsigned int major, const char *name,
				  const struct file_operations *fops)
{
	return __register_chrdev(major, 0, 256, name, fops);
}

static inline void unregister_chrdev(unsigned int major, const char *name)
{
	__unregister_chrdev(major, 0, 256, name);
}

L
Linus Torvalds 已提交
2288 2289
/* fs/block_dev.c */
#define BDEVNAME_SIZE	32	/* Largest string for a blockdev identifier */
2290
#define BDEVT_SIZE	10	/* Largest string for MAJ:MIN for blkdev */
2291 2292 2293

#ifdef CONFIG_BLOCK
#define BLKDEV_MAJOR_HASH_SIZE	255
L
Linus Torvalds 已提交
2294 2295 2296
extern const char *__bdevname(dev_t, char *buffer);
extern const char *bdevname(struct block_device *bdev, char *buffer);
extern struct block_device *lookup_bdev(const char *);
2297
extern void blkdev_show(struct seq_file *,off_t);
2298

2299 2300 2301
#else
#define BLKDEV_MAJOR_HASH_SIZE	0
#endif
L
Linus Torvalds 已提交
2302 2303 2304 2305 2306 2307 2308

extern void init_special_inode(struct inode *, umode_t, dev_t);

/* Invalid inode operations -- fs/bad_inode.c */
extern void make_bad_inode(struct inode *);
extern int is_bad_inode(struct inode *);

2309
#ifdef CONFIG_BLOCK
L
Linus Torvalds 已提交
2310 2311 2312 2313 2314 2315 2316 2317 2318 2319
/*
 * return READ, READA, or WRITE
 */
#define bio_rw(bio)		((bio)->bi_rw & (RW_MASK | RWA_MASK))

/*
 * return data direction, READ or WRITE
 */
#define bio_data_dir(bio)	((bio)->bi_rw & 1)

2320 2321
extern void check_disk_size_change(struct gendisk *disk,
				   struct block_device *bdev);
2322
extern int revalidate_disk(struct gendisk *);
L
Linus Torvalds 已提交
2323
extern int check_disk_change(struct block_device *);
2324
extern int __invalidate_device(struct block_device *, bool);
L
Linus Torvalds 已提交
2325
extern int invalidate_partition(struct gendisk *, int);
2326
#endif
L
Linus Torvalds 已提交
2327 2328
unsigned long invalidate_mapping_pages(struct address_space *mapping,
					pgoff_t start, pgoff_t end);
2329

L
Linus Torvalds 已提交
2330 2331 2332 2333
static inline void invalidate_remote_inode(struct inode *inode)
{
	if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
	    S_ISLNK(inode->i_mode))
2334
		invalidate_mapping_pages(inode->i_mapping, 0, -1);
L
Linus Torvalds 已提交
2335 2336 2337 2338 2339 2340 2341 2342
}
extern int invalidate_inode_pages2(struct address_space *mapping);
extern int invalidate_inode_pages2_range(struct address_space *mapping,
					 pgoff_t start, pgoff_t end);
extern int write_inode_now(struct inode *, int);
extern int filemap_fdatawrite(struct address_space *);
extern int filemap_flush(struct address_space *);
extern int filemap_fdatawait(struct address_space *);
2343 2344
extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
				   loff_t lend);
L
Linus Torvalds 已提交
2345 2346 2347
extern int filemap_write_and_wait(struct address_space *mapping);
extern int filemap_write_and_wait_range(struct address_space *mapping,
				        loff_t lstart, loff_t lend);
2348 2349
extern int __filemap_fdatawrite_range(struct address_space *mapping,
				loff_t start, loff_t end, int sync_mode);
2350 2351
extern int filemap_fdatawrite_range(struct address_space *mapping,
				loff_t start, loff_t end);
2352

2353 2354 2355
extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
			   int datasync);
extern int vfs_fsync(struct file *file, int datasync);
2356 2357 2358 2359 2360 2361 2362
static inline int generic_write_sync(struct file *file, loff_t pos, loff_t count)
{
	if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
		return 0;
	return vfs_fsync_range(file, pos, pos + count - 1,
			       (file->f_flags & __O_SYNC) ? 0 : 1);
}
L
Linus Torvalds 已提交
2363 2364
extern void emergency_sync(void);
extern void emergency_remount(void);
2365
#ifdef CONFIG_BLOCK
L
Linus Torvalds 已提交
2366
extern sector_t bmap(struct inode *, sector_t);
2367
#endif
2368
extern int notify_change(struct dentry *, struct iattr *, struct inode **);
2369
extern int inode_permission(struct inode *, int);
2370
extern int __inode_permission(struct inode *, int);
2371
extern int generic_permission(struct inode *, int);
M
Miklos Szeredi 已提交
2372
extern int __check_sticky(struct inode *dir, struct inode *inode);
L
Linus Torvalds 已提交
2373

2374 2375 2376 2377 2378
static inline bool execute_ok(struct inode *inode)
{
	return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
}

2379 2380 2381 2382 2383 2384 2385
static inline void file_start_write(struct file *file)
{
	if (!S_ISREG(file_inode(file)->i_mode))
		return;
	__sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true);
}

2386 2387 2388 2389 2390 2391 2392
static inline bool file_start_write_trylock(struct file *file)
{
	if (!S_ISREG(file_inode(file)->i_mode))
		return true;
	return __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, false);
}

2393 2394 2395 2396 2397 2398 2399
static inline void file_end_write(struct file *file)
{
	if (!S_ISREG(file_inode(file)->i_mode))
		return;
	__sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
}

2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421
/*
 * get_write_access() gets write permission for a file.
 * put_write_access() releases this write permission.
 * This is used for regular files.
 * We cannot support write (and maybe mmap read-write shared) accesses and
 * MAP_DENYWRITE mmappings simultaneously. The i_writecount field of an inode
 * can have the following values:
 * 0: no writers, no VM_DENYWRITE mappings
 * < 0: (-i_writecount) vm_area_structs with VM_DENYWRITE set exist
 * > 0: (i_writecount) users are writing to the file.
 *
 * Normally we operate on that counter with atomic_{inc,dec} and it's safe
 * except for the cases where we don't hold i_writecount yet. Then we need to
 * use {get,deny}_write_access() - these functions check the sign and refuse
 * to do the change if sign is wrong.
 */
static inline int get_write_access(struct inode *inode)
{
	return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
}
static inline int deny_write_access(struct file *file)
{
A
Al Viro 已提交
2422
	struct inode *inode = file_inode(file);
2423 2424
	return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
}
L
Linus Torvalds 已提交
2425 2426 2427 2428 2429 2430 2431
static inline void put_write_access(struct inode * inode)
{
	atomic_dec(&inode->i_writecount);
}
static inline void allow_write_access(struct file *file)
{
	if (file)
A
Al Viro 已提交
2432
		atomic_inc(&file_inode(file)->i_writecount);
L
Linus Torvalds 已提交
2433
}
2434 2435 2436 2437 2438
static inline bool inode_is_open_for_write(const struct inode *inode)
{
	return atomic_read(&inode->i_writecount) > 0;
}

M
Mimi Zohar 已提交
2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458
#ifdef CONFIG_IMA
static inline void i_readcount_dec(struct inode *inode)
{
	BUG_ON(!atomic_read(&inode->i_readcount));
	atomic_dec(&inode->i_readcount);
}
static inline void i_readcount_inc(struct inode *inode)
{
	atomic_inc(&inode->i_readcount);
}
#else
static inline void i_readcount_dec(struct inode *inode)
{
	return;
}
static inline void i_readcount_inc(struct inode *inode)
{
	return;
}
#endif
U
Ulrich Drepper 已提交
2459
extern int do_pipe_flags(int *, int);
L
Linus Torvalds 已提交
2460

M
Mimi Zohar 已提交
2461
extern int kernel_read(struct file *, loff_t, char *, unsigned long);
2462
extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
A
Al Viro 已提交
2463
extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
L
Linus Torvalds 已提交
2464 2465 2466 2467
extern struct file * open_exec(const char *);
 
/* fs/dcache.c -- generic fs support functions */
extern int is_subdir(struct dentry *, struct dentry *);
2468
extern int path_is_under(struct path *, struct path *);
L
Linus Torvalds 已提交
2469 2470 2471 2472

#include <linux/err.h>

/* needed for stackable file system support */
2473
extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
L
Linus Torvalds 已提交
2474

2475
extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
L
Linus Torvalds 已提交
2476

2477
extern int inode_init_always(struct super_block *, struct inode *);
L
Linus Torvalds 已提交
2478
extern void inode_init_once(struct inode *);
2479
extern void address_space_init_once(struct address_space *mapping);
L
Linus Torvalds 已提交
2480 2481 2482
extern struct inode * igrab(struct inode *);
extern ino_t iunique(struct super_block *, ino_t);
extern int inode_needs_sync(struct inode *inode);
2483
extern int generic_delete_inode(struct inode *inode);
2484 2485 2486 2487
static inline int generic_drop_inode(struct inode *inode)
{
	return !inode->i_nlink || inode_unhashed(inode);
}
L
Linus Torvalds 已提交
2488

2489 2490 2491
extern struct inode *ilookup5_nowait(struct super_block *sb,
		unsigned long hashval, int (*test)(struct inode *, void *),
		void *data);
L
Linus Torvalds 已提交
2492 2493 2494 2495 2496 2497
extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
		int (*test)(struct inode *, void *), void *data);
extern struct inode *ilookup(struct super_block *sb, unsigned long ino);

extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
extern struct inode * iget_locked(struct super_block *, unsigned long);
2498 2499 2500 2501 2502
extern struct inode *find_inode_nowait(struct super_block *,
				       unsigned long,
				       int (*match)(struct inode *,
						    unsigned long, void *),
				       void *data);
A
Al Viro 已提交
2503 2504
extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
extern int insert_inode_locked(struct inode *);
2505 2506 2507 2508 2509
#ifdef CONFIG_DEBUG_LOCK_ALLOC
extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
#else
static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
#endif
L
Linus Torvalds 已提交
2510
extern void unlock_new_inode(struct inode *);
2511
extern unsigned int get_next_ino(void);
L
Linus Torvalds 已提交
2512 2513

extern void __iget(struct inode * inode);
2514
extern void iget_failed(struct inode *);
2515
extern void clear_inode(struct inode *);
C
Christoph Hellwig 已提交
2516
extern void __destroy_inode(struct inode *);
2517 2518
extern struct inode *new_inode_pseudo(struct super_block *sb);
extern struct inode *new_inode(struct super_block *sb);
2519
extern void free_inode_nonrcu(struct inode *inode);
2520
extern int should_remove_suid(struct dentry *);
2521
extern int file_remove_suid(struct file *);
L
Linus Torvalds 已提交
2522 2523

extern void __insert_inode_hash(struct inode *, unsigned long hashval);
2524 2525
static inline void insert_inode_hash(struct inode *inode)
{
L
Linus Torvalds 已提交
2526 2527
	__insert_inode_hash(inode, inode->i_ino);
}
2528 2529 2530 2531 2532 2533 2534 2535

extern void __remove_inode_hash(struct inode *);
static inline void remove_inode_hash(struct inode *inode)
{
	if (!inode_unhashed(inode))
		__remove_inode_hash(inode);
}

2536
extern void inode_sb_list_add(struct inode *inode);
L
Linus Torvalds 已提交
2537

2538
#ifdef CONFIG_BLOCK
L
Linus Torvalds 已提交
2539 2540
extern void submit_bio(int, struct bio *);
extern int bdev_read_only(struct block_device *);
2541
#endif
L
Linus Torvalds 已提交
2542 2543 2544 2545 2546 2547 2548
extern int set_blocksize(struct block_device *, int);
extern int sb_set_blocksize(struct super_block *, int);
extern int sb_min_blocksize(struct super_block *, int);

extern int generic_file_mmap(struct file *, struct vm_area_struct *);
extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
A
Al Viro 已提交
2549
extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
2550 2551
extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);
A
Al Viro 已提交
2552
extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *, loff_t);
2553
extern ssize_t generic_perform_write(struct file *, struct iov_iter *, loff_t);
L
Linus Torvalds 已提交
2554 2555
extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
2556 2557
extern ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
extern ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
A
Andrew Morton 已提交
2558

2559 2560 2561
ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos);
ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos);

2562
/* fs/block_dev.c */
2563
extern ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to);
2564
extern ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from);
2565 2566
extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
			int datasync);
A
Al Viro 已提交
2567
extern void block_sync_page(struct page *page);
2568

A
Andrew Morton 已提交
2569
/* fs/splice.c */
2570
extern ssize_t generic_file_splice_read(struct file *, loff_t *,
A
Andrew Morton 已提交
2571
		struct pipe_inode_info *, size_t, unsigned int);
2572 2573
extern ssize_t default_file_splice_read(struct file *, loff_t *,
		struct pipe_inode_info *, size_t, unsigned int);
A
Al Viro 已提交
2574
extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
2575
		struct file *, loff_t *, size_t, unsigned int);
A
Andrew Morton 已提交
2576
extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
2577
		struct file *out, loff_t *, size_t len, unsigned int flags);
2578 2579 2580
extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
		loff_t *opos, size_t len, unsigned int flags);

A
Andrew Morton 已提交
2581

L
Linus Torvalds 已提交
2582 2583
extern void
file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
2584 2585
extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
extern loff_t no_llseek(struct file *file, loff_t offset, int whence);
J
Jie Liu 已提交
2586
extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
2587
extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
A
Andi Kleen 已提交
2588
extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
2589
		int whence, loff_t maxsize, loff_t eof);
A
Al Viro 已提交
2590 2591
extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
		int whence, loff_t size);
L
Linus Torvalds 已提交
2592 2593 2594
extern int generic_file_open(struct inode * inode, struct file * filp);
extern int nonseekable_open(struct inode * inode, struct file * filp);

2595 2596
ssize_t dax_do_io(int rw, struct kiocb *, struct inode *, struct iov_iter *,
		loff_t, get_block_t, dio_iodone_t, int flags);
2597
int dax_clear_blocks(struct inode *, sector_t block, long size);
M
Matthew Wilcox 已提交
2598
int dax_zero_page_range(struct inode *, loff_t from, unsigned len, get_block_t);
2599
int dax_truncate_page(struct inode *, loff_t from, get_block_t);
2600 2601
int dax_fault(struct vm_area_struct *, struct vm_fault *, get_block_t);
#define dax_mkwrite(vma, vmf, gb)	dax_fault(vma, vmf, gb)
2602

2603
#ifdef CONFIG_BLOCK
2604 2605
typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode,
			    loff_t file_offset);
L
Linus Torvalds 已提交
2606 2607

enum {
2608 2609 2610 2611 2612
	/* need locking between buffered and direct access */
	DIO_LOCKING	= 0x01,

	/* filesystem does not support filling holes */
	DIO_SKIP_HOLES	= 0x02,
2613 2614 2615

	/* filesystem can handle aio writes beyond i_size */
	DIO_ASYNC_EXTEND = 0x04,
L
Linus Torvalds 已提交
2616 2617
};

2618 2619 2620
void dio_end_io(struct bio *bio, int error);

ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
2621 2622
	struct block_device *bdev, struct iov_iter *iter, loff_t offset,
	get_block_t get_block, dio_iodone_t end_io,
2623
	dio_submit_t submit_io,	int flags);
2624

L
Linus Torvalds 已提交
2625
static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
2626 2627
		struct inode *inode, struct iov_iter *iter, loff_t offset,
		get_block_t get_block)
L
Linus Torvalds 已提交
2628
{
2629 2630
	return __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iter,
				    offset, get_block, NULL, NULL,
2631
				    DIO_LOCKING | DIO_SKIP_HOLES);
L
Linus Torvalds 已提交
2632
}
2633
#endif
L
Linus Torvalds 已提交
2634

2635 2636 2637
void inode_dio_wait(struct inode *inode);
void inode_dio_done(struct inode *inode);

2638 2639 2640
extern void inode_set_flags(struct inode *inode, unsigned int flags,
			    unsigned int mask);

2641
extern const struct file_operations generic_ro_fops;
L
Linus Torvalds 已提交
2642 2643 2644

#define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))

A
Al Viro 已提交
2645
extern int readlink_copy(char __user *, int, const char *);
L
Linus Torvalds 已提交
2646
extern int page_readlink(struct dentry *, char __user *, int);
2647 2648
extern void *page_follow_link_light(struct dentry *, struct nameidata *);
extern void page_put_link(struct dentry *, struct nameidata *, void *);
2649
extern int __page_symlink(struct inode *inode, const char *symname, int len,
2650
		int nofs);
L
Linus Torvalds 已提交
2651
extern int page_symlink(struct inode *inode, const char *symname, int len);
2652
extern const struct inode_operations page_symlink_inode_operations;
A
Al Viro 已提交
2653
extern void kfree_put_link(struct dentry *, struct nameidata *, void *);
L
Linus Torvalds 已提交
2654 2655
extern int generic_readlink(struct dentry *, char __user *, int);
extern void generic_fillattr(struct inode *, struct kstat *);
J
J. Bruce Fields 已提交
2656
int vfs_getattr_nosec(struct path *path, struct kstat *stat);
A
Al Viro 已提交
2657
extern int vfs_getattr(struct path *, struct kstat *);
2658
void __inode_add_bytes(struct inode *inode, loff_t bytes);
L
Linus Torvalds 已提交
2659
void inode_add_bytes(struct inode *inode, loff_t bytes);
2660
void __inode_sub_bytes(struct inode *inode, loff_t bytes);
L
Linus Torvalds 已提交
2661 2662 2663 2664 2665
void inode_sub_bytes(struct inode *inode, loff_t bytes);
loff_t inode_get_bytes(struct inode *inode);
void inode_set_bytes(struct inode *inode, loff_t bytes);

extern int vfs_readdir(struct file *, filldir_t, void *);
2666
extern int iterate_dir(struct file *, struct dir_context *);
L
Linus Torvalds 已提交
2667

2668 2669
extern int vfs_stat(const char __user *, struct kstat *);
extern int vfs_lstat(const char __user *, struct kstat *);
L
Linus Torvalds 已提交
2670
extern int vfs_fstat(unsigned int, struct kstat *);
2671
extern int vfs_fstatat(int , const char __user *, struct kstat *, int);
L
Linus Torvalds 已提交
2672

2673 2674
extern int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
		    unsigned long arg);
2675
extern int __generic_block_fiemap(struct inode *inode,
J
Josef Bacik 已提交
2676 2677 2678
				  struct fiemap_extent_info *fieinfo,
				  loff_t start, loff_t len,
				  get_block_t *get_block);
2679 2680 2681
extern int generic_block_fiemap(struct inode *inode,
				struct fiemap_extent_info *fieinfo, u64 start,
				u64 len, get_block_t *get_block);
L
Linus Torvalds 已提交
2682

2683 2684
extern void get_filesystem(struct file_system_type *fs);
extern void put_filesystem(struct file_system_type *fs);
L
Linus Torvalds 已提交
2685 2686
extern struct file_system_type *get_fs_type(const char *name);
extern struct super_block *get_super(struct block_device *);
2687
extern struct super_block *get_super_thawed(struct block_device *);
2688
extern struct super_block *get_active_super(struct block_device *bdev);
L
Linus Torvalds 已提交
2689
extern void drop_super(struct super_block *sb);
A
Al Viro 已提交
2690
extern void iterate_supers(void (*)(struct super_block *, void *), void *);
A
Al Viro 已提交
2691 2692
extern void iterate_supers_type(struct file_system_type *,
			        void (*)(struct super_block *, void *), void *);
L
Linus Torvalds 已提交
2693 2694 2695 2696

extern int dcache_dir_open(struct inode *, struct file *);
extern int dcache_dir_close(struct inode *, struct file *);
extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
2697
extern int dcache_readdir(struct file *, struct dir_context *);
2698
extern int simple_setattr(struct dentry *, struct iattr *);
L
Linus Torvalds 已提交
2699
extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
2700
extern int simple_statfs(struct dentry *, struct kstatfs *);
S
Stephen Boyd 已提交
2701
extern int simple_open(struct inode *inode, struct file *file);
L
Linus Torvalds 已提交
2702 2703 2704 2705
extern int simple_link(struct dentry *, struct inode *, struct dentry *);
extern int simple_unlink(struct inode *, struct dentry *);
extern int simple_rmdir(struct inode *, struct dentry *);
extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
2706
extern int noop_fsync(struct file *, loff_t, loff_t, int);
L
Linus Torvalds 已提交
2707 2708
extern int simple_empty(struct dentry *);
extern int simple_readpage(struct file *file, struct page *page);
2709 2710 2711 2712 2713 2714
extern int simple_write_begin(struct file *file, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned flags,
			struct page **pagep, void **fsdata);
extern int simple_write_end(struct file *file, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned copied,
			struct page *page, void *fsdata);
2715
extern int always_delete_dentry(const struct dentry *);
A
Al Viro 已提交
2716
extern struct inode *alloc_anon_inode(struct super_block *);
2717
extern int simple_nosetlease(struct file *, long, struct file_lock **, void **);
2718
extern const struct dentry_operations simple_dentry_operations;
L
Linus Torvalds 已提交
2719

A
Al Viro 已提交
2720
extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
L
Linus Torvalds 已提交
2721
extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
2722
extern const struct file_operations simple_dir_operations;
2723
extern const struct inode_operations simple_dir_inode_operations;
2724
struct tree_descr { char *name; const struct file_operations *ops; int mode; };
L
Linus Torvalds 已提交
2725
struct dentry *d_alloc_name(struct dentry *, const char *);
2726
extern int simple_fill_super(struct super_block *, unsigned long, struct tree_descr *);
2727
extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
L
Linus Torvalds 已提交
2728 2729
extern void simple_release_fs(struct vfsmount **mount, int *count);

2730 2731
extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
			loff_t *ppos, const void *from, size_t available);
2732 2733
extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
		const void __user *from, size_t count);
L
Linus Torvalds 已提交
2734

2735
extern int __generic_file_fsync(struct file *, loff_t, loff_t, int);
2736
extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
A
Al Viro 已提交
2737

2738 2739
extern int generic_check_addressable(unsigned, u64);

2740
#ifdef CONFIG_MIGRATION
2741
extern int buffer_migrate_page(struct address_space *,
2742 2743
				struct page *, struct page *,
				enum migrate_mode);
2744 2745 2746 2747
#else
#define buffer_migrate_page NULL
#endif

N
npiggin@suse.de 已提交
2748 2749
extern int inode_change_ok(const struct inode *, struct iattr *);
extern int inode_newsize_ok(const struct inode *, loff_t offset);
C
Christoph Hellwig 已提交
2750
extern void setattr_copy(struct inode *inode, const struct iattr *attr);
L
Linus Torvalds 已提交
2751

2752
extern int file_update_time(struct file *file);
L
Linus Torvalds 已提交
2753

2754
extern int generic_show_options(struct seq_file *m, struct dentry *root);
2755
extern void save_mount_options(struct super_block *sb, char *options);
2756
extern void replace_mount_options(struct super_block *sb, char *options);
2757

2758 2759 2760 2761 2762
static inline bool io_is_direct(struct file *filp)
{
	return (filp->f_flags & O_DIRECT) || IS_DAX(file_inode(filp));
}

L
Linus Torvalds 已提交
2763 2764 2765 2766
static inline ino_t parent_ino(struct dentry *dentry)
{
	ino_t res;

N
Nick Piggin 已提交
2767 2768 2769 2770
	/*
	 * Don't strictly need d_lock here? If the parent ino could change
	 * then surely we'd have a deeper race in the caller?
	 */
L
Linus Torvalds 已提交
2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795
	spin_lock(&dentry->d_lock);
	res = dentry->d_parent->d_inode->i_ino;
	spin_unlock(&dentry->d_lock);
	return res;
}

/* Transaction based IO helpers */

/*
 * An argresp is stored in an allocated page and holds the
 * size of the argument or response, along with its content
 */
struct simple_transaction_argresp {
	ssize_t size;
	char data[0];
};

#define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))

char *simple_transaction_get(struct file *file, const char __user *buf,
				size_t size);
ssize_t simple_transaction_read(struct file *file, char __user *buf,
				size_t size, loff_t *pos);
int simple_transaction_release(struct inode *inode, struct file *file);

2796
void simple_transaction_set(struct file *file, size_t n);
L
Linus Torvalds 已提交
2797

2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819
/*
 * simple attribute files
 *
 * These attributes behave similar to those in sysfs:
 *
 * Writing to an attribute immediately sets a value, an open file can be
 * written to multiple times.
 *
 * Reading from an attribute creates a buffer from the value that might get
 * read with multiple read calls. When the attribute has been read
 * completely, no further read calls are possible until the file is opened
 * again.
 *
 * All attributes contain a text representation of a numeric value
 * that are accessed with the get() and set() functions.
 */
#define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt)		\
static int __fops ## _open(struct inode *inode, struct file *file)	\
{									\
	__simple_attr_check_format(__fmt, 0ull);			\
	return simple_attr_open(inode, file, __get, __set, __fmt);	\
}									\
2820
static const struct file_operations __fops = {				\
2821 2822
	.owner	 = THIS_MODULE,						\
	.open	 = __fops ## _open,					\
2823
	.release = simple_attr_release,					\
2824 2825
	.read	 = simple_attr_read,					\
	.write	 = simple_attr_write,					\
2826
	.llseek	 = generic_file_llseek,					\
2827
}
2828

2829 2830
static inline __printf(1, 2)
void __simple_attr_check_format(const char *fmt, ...)
2831 2832 2833 2834 2835
{
	/* don't do anything, just let the compiler check the arguments; */
}

int simple_attr_open(struct inode *inode, struct file *file,
2836
		     int (*get)(void *, u64 *), int (*set)(void *, u64),
2837
		     const char *fmt);
2838
int simple_attr_release(struct inode *inode, struct file *file);
2839 2840 2841 2842 2843
ssize_t simple_attr_read(struct file *file, char __user *buf,
			 size_t len, loff_t *ppos);
ssize_t simple_attr_write(struct file *file, const char __user *buf,
			  size_t len, loff_t *ppos);

A
Alexey Dobriyan 已提交
2844
struct ctl_table;
2845
int proc_nr_files(struct ctl_table *table, int write,
2846
		  void __user *buffer, size_t *lenp, loff_t *ppos);
2847 2848
int proc_nr_dentry(struct ctl_table *table, int write,
		  void __user *buffer, size_t *lenp, loff_t *ppos);
2849 2850
int proc_nr_inodes(struct ctl_table *table, int write,
		   void __user *buffer, size_t *lenp, loff_t *ppos);
2851
int __init get_filesystem_list(char *buf);
2852

N
Namhyung Kim 已提交
2853
#define __FMODE_EXEC		((__force int) FMODE_EXEC)
2854 2855
#define __FMODE_NONOTIFY	((__force int) FMODE_NONOTIFY)

A
Al Viro 已提交
2856
#define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
E
Eric Paris 已提交
2857
#define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
2858
					    (flag & __FMODE_NONOTIFY)))
A
Al Viro 已提交
2859

A
Al Viro 已提交
2860
static inline int is_sxid(umode_t mode)
2861 2862 2863 2864
{
	return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
}

M
Miklos Szeredi 已提交
2865 2866 2867 2868 2869 2870 2871 2872
static inline int check_sticky(struct inode *dir, struct inode *inode)
{
	if (!(dir->i_mode & S_ISVTX))
		return 0;

	return __check_sticky(dir, inode);
}

2873 2874
static inline void inode_has_no_xattr(struct inode *inode)
{
A
Al Viro 已提交
2875
	if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & MS_NOSEC))
2876 2877 2878
		inode->i_flags |= S_NOSEC;
}

A
Al Viro 已提交
2879 2880 2881 2882 2883
static inline bool is_root_inode(struct inode *inode)
{
	return inode == inode->i_sb->s_root->d_inode;
}

2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913
static inline bool dir_emit(struct dir_context *ctx,
			    const char *name, int namelen,
			    u64 ino, unsigned type)
{
	return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0;
}
static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
{
	return ctx->actor(ctx, ".", 1, ctx->pos,
			  file->f_path.dentry->d_inode->i_ino, DT_DIR) == 0;
}
static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
{
	return ctx->actor(ctx, "..", 2, ctx->pos,
			  parent_ino(file->f_path.dentry), DT_DIR) == 0;
}
static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
{
	if (ctx->pos == 0) {
		if (!dir_emit_dot(file, ctx))
			return false;
		ctx->pos = 1;
	}
	if (ctx->pos == 1) {
		if (!dir_emit_dotdot(file, ctx))
			return false;
		ctx->pos = 2;
	}
	return true;
}
A
Al Viro 已提交
2914 2915 2916 2917 2918 2919
static inline bool dir_relax(struct inode *inode)
{
	mutex_unlock(&inode->i_mutex);
	mutex_lock(&inode->i_mutex);
	return !IS_DEADDIR(inode);
}
2920

L
Linus Torvalds 已提交
2921
#endif /* _LINUX_FS_H */