5 #include <linux/linkage.h>
6 #include <linux/wait.h>
7 #include <linux/kdev_t.h>
8 #include <linux/dcache.h>
9 #include <linux/path.h>
10 #include <linux/stat.h>
11 #include <linux/cache.h>
12 #include <linux/list.h>
13 #include <linux/list_lru.h>
14 #include <linux/llist.h>
15 #include <linux/radix-tree.h>
16 #include <linux/rbtree.h>
17 #include <linux/init.h>
18 #include <linux/pid.h>
19 #include <linux/bug.h>
20 #include <linux/mutex.h>
21 #include <linux/capability.h>
22 #include <linux/semaphore.h>
23 #include <linux/fiemap.h>
24 #include <linux/rculist_bl.h>
25 #include <linux/atomic.h>
26 #include <linux/shrinker.h>
27 #include <linux/migrate_mode.h>
28 #include <linux/uidgid.h>
29 #include <linux/lockdep.h>
30 #include <linux/percpu-rwsem.h>
31 #include <linux/blk_types.h>
33 #include <asm/byteorder.h>
34 #include <uapi/linux/fs.h>
36 struct export_operations;
42 struct pipe_inode_info;
43 struct poll_table_struct;
45 struct vm_area_struct;
48 struct swap_info_struct;
50 struct workqueue_struct;
52 extern void __init inode_init(void);
53 extern void __init inode_init_early(void);
54 extern void __init files_init(unsigned long);
56 extern struct files_stat_struct files_stat;
57 extern unsigned long get_max_files(void);
58 extern int sysctl_nr_open;
59 extern struct inodes_stat_t inodes_stat;
60 extern int leases_enable, lease_break_time;
61 extern int sysctl_protected_symlinks;
62 extern int sysctl_protected_hardlinks;
65 typedef int (get_block_t)(struct inode *inode, sector_t iblock,
66 struct buffer_head *bh_result, int create);
67 typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
68 ssize_t bytes, void *private);
70 #define MAY_EXEC 0x00000001
71 #define MAY_WRITE 0x00000002
72 #define MAY_READ 0x00000004
73 #define MAY_APPEND 0x00000008
74 #define MAY_ACCESS 0x00000010
75 #define MAY_OPEN 0x00000020
76 #define MAY_CHDIR 0x00000040
77 /* called from RCU mode, don't block */
78 #define MAY_NOT_BLOCK 0x00000080
81 * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond
82 * to O_WRONLY and O_RDWR via the strange trick in __dentry_open()
85 /* file is open for reading */
86 #define FMODE_READ ((__force fmode_t)0x1)
87 /* file is open for writing */
88 #define FMODE_WRITE ((__force fmode_t)0x2)
89 /* file is seekable */
90 #define FMODE_LSEEK ((__force fmode_t)0x4)
91 /* file can be accessed using pread */
92 #define FMODE_PREAD ((__force fmode_t)0x8)
93 /* file can be accessed using pwrite */
94 #define FMODE_PWRITE ((__force fmode_t)0x10)
95 /* File is opened for execution with sys_execve / sys_uselib */
96 #define FMODE_EXEC ((__force fmode_t)0x20)
97 /* File is opened with O_NDELAY (only set for block devices) */
98 #define FMODE_NDELAY ((__force fmode_t)0x40)
99 /* File is opened with O_EXCL (only set for block devices) */
100 #define FMODE_EXCL ((__force fmode_t)0x80)
101 /* File is opened using open(.., 3, ..) and is writeable only for ioctls
102 (specialy hack for floppy.c) */
103 #define FMODE_WRITE_IOCTL ((__force fmode_t)0x100)
104 /* 32bit hashes as llseek() offset (for directories) */
105 #define FMODE_32BITHASH ((__force fmode_t)0x200)
106 /* 64bit hashes as llseek() offset (for directories) */
107 #define FMODE_64BITHASH ((__force fmode_t)0x400)
110 * Don't update ctime and mtime.
112 * Currently a special hack for the XFS open_by_handle ioctl, but we'll
113 * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
115 #define FMODE_NOCMTIME ((__force fmode_t)0x800)
117 /* Expect random access pattern */
118 #define FMODE_RANDOM ((__force fmode_t)0x1000)
120 /* File is huge (eg. /dev/kmem): treat loff_t as unsigned */
121 #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
123 /* File is opened with O_PATH; almost nothing can be done with it */
124 #define FMODE_PATH ((__force fmode_t)0x4000)
126 /* File needs atomic accesses to f_pos */
127 #define FMODE_ATOMIC_POS ((__force fmode_t)0x8000)
129 /* File was opened by fanotify and shouldn't generate fanotify events */
130 #define FMODE_NONOTIFY ((__force fmode_t)0x1000000)
133 * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
134 * that indicates that they should check the contents of the iovec are
135 * valid, but not check the memory that the iovec elements
138 #define CHECK_IOVEC_ONLY -1
141 * The below are the various read and write types that we support. Some of
142 * them include behavioral modifiers that send information down to the
143 * block layer and IO scheduler. Terminology:
145 * The block layer uses device plugging to defer IO a little bit, in
146 * the hope that we will see more IO very shortly. This increases
147 * coalescing of adjacent IO and thus reduces the number of IOs we
148 * have to send to the device. It also allows for better queuing,
149 * if the IO isn't mergeable. If the caller is going to be waiting
150 * for the IO, then he must ensure that the device is unplugged so
151 * that the IO is dispatched to the driver.
153 * All IO is handled async in Linux. This is fine for background
154 * writes, but for reads or writes that someone waits for completion
155 * on, we want to notify the block layer and IO scheduler so that they
156 * know about it. That allows them to make better scheduling
157 * decisions. So when the below references 'sync' and 'async', it
158 * is referencing this priority hint.
160 * With that in mind, the available types are:
162 * READ A normal read operation. Device will be plugged.
163 * READ_SYNC A synchronous read. Device is not plugged, caller can
164 * immediately wait on this read without caring about
166 * READA Used for read-ahead operations. Lower priority, and the
167 * block layer could (in theory) choose to ignore this
168 * request if it runs into resource problems.
169 * WRITE A normal async write. Device will be plugged.
170 * WRITE_SYNC Synchronous write. Identical to WRITE, but passes down
171 * the hint that someone will be waiting on this IO
172 * shortly. The write equivalent of READ_SYNC.
173 * WRITE_ODIRECT Special case write for O_DIRECT only.
174 * WRITE_FLUSH Like WRITE_SYNC but with preceding cache flush.
175 * WRITE_FUA Like WRITE_SYNC but data is guaranteed to be on
176 * non-volatile media on completion.
177 * WRITE_FLUSH_FUA Combination of WRITE_FLUSH and FUA. The IO is preceded
178 * by a cache flush and data is guaranteed to be on
179 * non-volatile media on completion.
182 #define RW_MASK REQ_WRITE
183 #define RWA_MASK REQ_RAHEAD
186 #define WRITE RW_MASK
187 #define READA RWA_MASK
188 #define KERNEL_READ (READ|REQ_KERNEL)
189 #define KERNEL_WRITE (WRITE|REQ_KERNEL)
191 #define READ_SYNC (READ | REQ_SYNC)
192 #define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE)
193 #define WRITE_ODIRECT (WRITE | REQ_SYNC)
194 #define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH)
195 #define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA)
196 #define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA)
199 * Attribute flags. These should be or-ed together to figure out what
202 #define ATTR_MODE (1 << 0)
203 #define ATTR_UID (1 << 1)
204 #define ATTR_GID (1 << 2)
205 #define ATTR_SIZE (1 << 3)
206 #define ATTR_ATIME (1 << 4)
207 #define ATTR_MTIME (1 << 5)
208 #define ATTR_CTIME (1 << 6)
209 #define ATTR_ATIME_SET (1 << 7)
210 #define ATTR_MTIME_SET (1 << 8)
211 #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
212 #define ATTR_ATTR_FLAG (1 << 10)
213 #define ATTR_KILL_SUID (1 << 11)
214 #define ATTR_KILL_SGID (1 << 12)
215 #define ATTR_FILE (1 << 13)
216 #define ATTR_KILL_PRIV (1 << 14)
217 #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
218 #define ATTR_TIMES_SET (1 << 16)
221 * This is the Inode Attributes structure, used for notify_change(). It
222 * uses the above definitions as flags, to know which values have changed.
223 * Also, in this manner, a Filesystem can look at only the values it cares
224 * about. Basically, these are the attributes that the VFS layer can
225 * request to change from the FS layer.
227 * Derek Atkins <warlord@MIT.EDU> 94-10-20
230 unsigned int ia_valid;
235 struct timespec ia_atime;
236 struct timespec ia_mtime;
237 struct timespec ia_ctime;
240 * Not an attribute, but an auxiliary info for filesystems wanting to
241 * implement an ftruncate() like method. NOTE: filesystem should
242 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
244 struct file *ia_file;
248 * Includes for diskquotas.
250 #include <linux/quota.h>
253 * enum positive_aop_returns - aop return codes with specific semantics
255 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
256 * completed, that the page is still locked, and
257 * should be considered active. The VM uses this hint
258 * to return the page to the active list -- it won't
259 * be a candidate for writeback again in the near
260 * future. Other callers must be careful to unlock
261 * the page if they get this return. Returned by
264 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
265 * unlocked it and the page might have been truncated.
266 * The caller should back up to acquiring a new page and
267 * trying again. The aop will be taking reasonable
268 * precautions not to livelock. If the caller held a page
269 * reference, it should drop it before retrying. Returned
272 * address_space_operation functions return these large constants to indicate
273 * special semantics to the caller. These are much larger than the bytes in a
274 * page to allow for functions that return the number of bytes operated on in a
278 enum positive_aop_returns {
279 AOP_WRITEPAGE_ACTIVATE = 0x80000,
280 AOP_TRUNCATED_PAGE = 0x80001,
283 #define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */
284 #define AOP_FLAG_CONT_EXPAND 0x0002 /* called from cont_expand */
285 #define AOP_FLAG_NOFS 0x0004 /* used by filesystem to direct
286 * helper code (eg buffer layer)
287 * to clear GFP_FS from alloc */
290 * oh the beauties of C type declarations.
293 struct address_space;
294 struct writeback_control;
297 const struct iovec *iov;
298 unsigned long nr_segs;
303 size_t iov_iter_copy_from_user_atomic(struct page *page,
304 struct iov_iter *i, unsigned long offset, size_t bytes);
305 size_t iov_iter_copy_from_user(struct page *page,
306 struct iov_iter *i, unsigned long offset, size_t bytes);
307 void iov_iter_advance(struct iov_iter *i, size_t bytes);
308 int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes);
309 size_t iov_iter_single_seg_count(const struct iov_iter *i);
311 static inline void iov_iter_init(struct iov_iter *i,
312 const struct iovec *iov, unsigned long nr_segs,
313 size_t count, size_t written)
316 i->nr_segs = nr_segs;
318 i->count = count + written;
320 iov_iter_advance(i, written);
323 static inline size_t iov_iter_count(struct iov_iter *i)
329 * "descriptor" for what we're up to with a read.
330 * This allows us to use the same read code yet
331 * have multiple different users of the data that
332 * we read from a file.
334 * The simplest case just copies the data to user
347 typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
348 unsigned long, unsigned long);
350 struct address_space_operations {
351 int (*writepage)(struct page *page, struct writeback_control *wbc);
352 int (*readpage)(struct file *, struct page *);
354 /* Write back some dirty pages from this mapping. */
355 int (*writepages)(struct address_space *, struct writeback_control *);
357 /* Set a page dirty. Return true if this dirtied it */
358 int (*set_page_dirty)(struct page *page);
360 int (*readpages)(struct file *filp, struct address_space *mapping,
361 struct list_head *pages, unsigned nr_pages);
363 int (*write_begin)(struct file *, struct address_space *mapping,
364 loff_t pos, unsigned len, unsigned flags,
365 struct page **pagep, void **fsdata);
366 int (*write_end)(struct file *, struct address_space *mapping,
367 loff_t pos, unsigned len, unsigned copied,
368 struct page *page, void *fsdata);
370 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
371 sector_t (*bmap)(struct address_space *, sector_t);
372 void (*invalidatepage) (struct page *, unsigned int, unsigned int);
373 int (*releasepage) (struct page *, gfp_t);
374 void (*freepage)(struct page *);
375 ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
376 loff_t offset, unsigned long nr_segs);
377 int (*get_xip_mem)(struct address_space *, pgoff_t, int,
378 void **, unsigned long *);
380 * migrate the contents of a page to the specified target. If
381 * migrate_mode is MIGRATE_ASYNC, it must not block.
383 int (*migratepage) (struct address_space *,
384 struct page *, struct page *, enum migrate_mode);
385 int (*launder_page) (struct page *);
386 int (*is_partially_uptodate) (struct page *, read_descriptor_t *,
388 void (*is_dirty_writeback) (struct page *, bool *, bool *);
389 int (*error_remove_page)(struct address_space *, struct page *);
391 /* swapfile support */
392 int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
394 void (*swap_deactivate)(struct file *file);
397 extern const struct address_space_operations empty_aops;
400 * pagecache_write_begin/pagecache_write_end must be used by general code
401 * to write into the pagecache.
403 int pagecache_write_begin(struct file *, struct address_space *mapping,
404 loff_t pos, unsigned len, unsigned flags,
405 struct page **pagep, void **fsdata);
407 int pagecache_write_end(struct file *, struct address_space *mapping,
408 loff_t pos, unsigned len, unsigned copied,
409 struct page *page, void *fsdata);
411 struct backing_dev_info;
412 struct address_space {
413 struct inode *host; /* owner: inode, block_device */
414 struct radix_tree_root page_tree; /* radix tree of all pages */
415 spinlock_t tree_lock; /* and lock protecting it */
416 unsigned int i_mmap_writable;/* count VM_SHARED mappings */
417 struct rb_root i_mmap; /* tree of private and shared mappings */
418 struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
419 struct mutex i_mmap_mutex; /* protect tree, count, list */
420 /* Protected by tree_lock together with the radix tree */
421 unsigned long nrpages; /* number of total pages */
422 unsigned long nrshadows; /* number of shadow entries */
423 pgoff_t writeback_index;/* writeback starts here */
424 const struct address_space_operations *a_ops; /* methods */
425 unsigned long flags; /* error bits/gfp mask */
426 struct backing_dev_info *backing_dev_info; /* device readahead, etc */
427 spinlock_t private_lock; /* for use by the address_space */
428 struct list_head private_list; /* ditto */
429 void *private_data; /* ditto */
430 } __attribute__((aligned(sizeof(long))));
432 * On most architectures that alignment is already the case; but
433 * must be enforced here for CRIS, to let the least significant bit
434 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
436 struct request_queue;
438 struct block_device {
439 dev_t bd_dev; /* not a kdev_t - it's a search key */
441 struct inode * bd_inode; /* will die */
442 struct super_block * bd_super;
443 struct mutex bd_mutex; /* open/close mutex */
444 struct list_head bd_inodes;
448 bool bd_write_holder;
450 struct list_head bd_holder_disks;
452 struct block_device * bd_contains;
453 unsigned bd_block_size;
454 struct hd_struct * bd_part;
455 /* number of times partitions within this device have been opened. */
456 unsigned bd_part_count;
458 struct gendisk * bd_disk;
459 struct request_queue * bd_queue;
460 struct list_head bd_list;
462 * Private data. You must have bd_claim'ed the block_device
463 * to use this. NOTE: bd_claim allows an owner to claim
464 * the same device multiple times, the owner must take special
465 * care to not mess up bd_private for that case.
467 unsigned long bd_private;
469 /* The counter of freeze processes */
470 int bd_fsfreeze_count;
471 /* Mutex for freeze */
472 struct mutex bd_fsfreeze_mutex;
476 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
479 #define PAGECACHE_TAG_DIRTY 0
480 #define PAGECACHE_TAG_WRITEBACK 1
481 #define PAGECACHE_TAG_TOWRITE 2
483 int mapping_tagged(struct address_space *mapping, int tag);
486 * Might pages of this file be mapped into userspace?
488 static inline int mapping_mapped(struct address_space *mapping)
490 return !RB_EMPTY_ROOT(&mapping->i_mmap) ||
491 !list_empty(&mapping->i_mmap_nonlinear);
495 * Might pages of this file have been modified in userspace?
496 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
497 * marks vma as VM_SHARED if it is shared, and the file was opened for
498 * writing i.e. vma may be mprotected writable even if now readonly.
500 static inline int mapping_writably_mapped(struct address_space *mapping)
502 return mapping->i_mmap_writable != 0;
506 * Use sequence counter to get consistent i_size on 32-bit processors.
508 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
509 #include <linux/seqlock.h>
510 #define __NEED_I_SIZE_ORDERED
511 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
513 #define i_size_ordered_init(inode) do { } while (0)
517 #define ACL_NOT_CACHED ((void *)(-1))
519 #define IOP_FASTPERM 0x0001
520 #define IOP_LOOKUP 0x0002
521 #define IOP_NOFOLLOW 0x0004
524 * Keep mostly read-only and often accessed (especially for
525 * the RCU path lookup and 'stat' data) fields at the beginning
526 * of the 'struct inode'
530 unsigned short i_opflags;
533 unsigned int i_flags;
535 #ifdef CONFIG_FS_POSIX_ACL
536 struct posix_acl *i_acl;
537 struct posix_acl *i_default_acl;
540 const struct inode_operations *i_op;
541 struct super_block *i_sb;
542 struct address_space *i_mapping;
544 #ifdef CONFIG_SECURITY
548 /* Stat data, not accessed from path walking */
551 * Filesystems may only read i_nlink directly. They shall use the
552 * following functions for modification:
554 * (set|clear|inc|drop)_nlink
555 * inode_(inc|dec)_link_count
558 const unsigned int i_nlink;
559 unsigned int __i_nlink;
563 struct timespec i_atime;
564 struct timespec i_mtime;
565 struct timespec i_ctime;
566 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
567 unsigned short i_bytes;
568 unsigned int i_blkbits;
571 #ifdef __NEED_I_SIZE_ORDERED
572 seqcount_t i_size_seqcount;
576 unsigned long i_state;
577 struct mutex i_mutex;
579 unsigned long dirtied_when; /* jiffies of first dirtying */
581 struct hlist_node i_hash;
582 struct list_head i_wb_list; /* backing dev IO list */
583 struct list_head i_lru; /* inode LRU list */
584 struct list_head i_sb_list;
586 struct hlist_head i_dentry;
587 struct rcu_head i_rcu;
591 atomic_t i_dio_count;
592 atomic_t i_writecount;
594 atomic_t i_readcount; /* struct files open RO */
596 const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
597 struct file_lock *i_flock;
598 struct address_space i_data;
600 struct dquot *i_dquot[MAXQUOTAS];
602 struct list_head i_devices;
604 struct pipe_inode_info *i_pipe;
605 struct block_device *i_bdev;
611 #ifdef CONFIG_FSNOTIFY
612 __u32 i_fsnotify_mask; /* all events this inode cares about */
613 struct hlist_head i_fsnotify_marks;
616 void *i_private; /* fs or device private pointer */
619 static inline int inode_unhashed(struct inode *inode)
621 return hlist_unhashed(&inode->i_hash);
625 * inode->i_mutex nesting subclasses for the lock validator:
627 * 0: the object of the current VFS operation
631 * 4: second non-directory
632 * The last is for certain operations (such as rename) which lock two
633 * non-directories at once.
635 * The locking order between these classes is
636 * parent -> child -> normal -> xattr -> second non-directory
638 enum inode_i_mutex_lock_class
647 void lock_two_nondirectories(struct inode *, struct inode*);
648 void unlock_two_nondirectories(struct inode *, struct inode*);
651 * NOTE: in a 32bit arch with a preemptable kernel and
652 * an UP compile the i_size_read/write must be atomic
653 * with respect to the local cpu (unlike with preempt disabled),
654 * but they don't need to be atomic with respect to other cpus like in
655 * true SMP (so they need either to either locally disable irq around
656 * the read or for example on x86 they can be still implemented as a
657 * cmpxchg8b without the need of the lock prefix). For SMP compiles
658 * and 64bit archs it makes no difference if preempt is enabled or not.
660 static inline loff_t i_size_read(const struct inode *inode)
662 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
667 seq = read_seqcount_begin(&inode->i_size_seqcount);
668 i_size = inode->i_size;
669 } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
671 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
675 i_size = inode->i_size;
679 return inode->i_size;
684 * NOTE: unlike i_size_read(), i_size_write() does need locking around it
685 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
686 * can be lost, resulting in subsequent i_size_read() calls spinning forever.
688 static inline void i_size_write(struct inode *inode, loff_t i_size)
690 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
692 write_seqcount_begin(&inode->i_size_seqcount);
693 inode->i_size = i_size;
694 write_seqcount_end(&inode->i_size_seqcount);
696 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
698 inode->i_size = i_size;
701 inode->i_size = i_size;
705 /* Helper functions so that in most cases filesystems will
706 * not need to deal directly with kuid_t and kgid_t and can
707 * instead deal with the raw numeric values that are stored
710 static inline uid_t i_uid_read(const struct inode *inode)
712 return from_kuid(&init_user_ns, inode->i_uid);
715 static inline gid_t i_gid_read(const struct inode *inode)
717 return from_kgid(&init_user_ns, inode->i_gid);
720 static inline void i_uid_write(struct inode *inode, uid_t uid)
722 inode->i_uid = make_kuid(&init_user_ns, uid);
725 static inline void i_gid_write(struct inode *inode, gid_t gid)
727 inode->i_gid = make_kgid(&init_user_ns, gid);
730 static inline unsigned iminor(const struct inode *inode)
732 return MINOR(inode->i_rdev);
735 static inline unsigned imajor(const struct inode *inode)
737 return MAJOR(inode->i_rdev);
740 extern struct block_device *I_BDEV(struct inode *inode);
743 rwlock_t lock; /* protects pid, uid, euid fields */
744 struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
745 enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
746 kuid_t uid, euid; /* uid/euid of process setting the owner */
747 int signum; /* posix.1b rt signal to be delivered on IO */
751 * Track a single file's readahead state
753 struct file_ra_state {
754 pgoff_t start; /* where readahead started */
755 unsigned int size; /* # of readahead pages */
756 unsigned int async_size; /* do asynchronous readahead when
757 there are only # of pages ahead */
759 unsigned int ra_pages; /* Maximum readahead window */
760 unsigned int mmap_miss; /* Cache miss stat for mmap accesses */
761 loff_t prev_pos; /* Cache last read() position */
765 * Check if @index falls in the readahead windows.
767 static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
769 return (index >= ra->start &&
770 index < ra->start + ra->size);
773 #define FILE_MNT_WRITE_TAKEN 1
774 #define FILE_MNT_WRITE_RELEASED 2
778 struct llist_node fu_llist;
779 struct rcu_head fu_rcuhead;
782 #define f_dentry f_path.dentry
783 struct inode *f_inode; /* cached value */
784 const struct file_operations *f_op;
787 * Protects f_ep_links, f_flags.
788 * Must not be taken from IRQ context.
791 atomic_long_t f_count;
792 unsigned int f_flags;
794 struct mutex f_pos_lock;
796 struct fown_struct f_owner;
797 const struct cred *f_cred;
798 struct file_ra_state f_ra;
801 #ifdef CONFIG_SECURITY
804 /* needed for tty driver, and maybe others */
808 /* Used by fs/eventpoll.c to link all the hooks to this file */
809 struct list_head f_ep_links;
810 struct list_head f_tfile_llink;
811 #endif /* #ifdef CONFIG_EPOLL */
812 struct address_space *f_mapping;
813 #ifdef CONFIG_DEBUG_WRITECOUNT
814 unsigned long f_mnt_write_state;
816 } __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
821 /* file identifier */
822 unsigned char f_handle[0];
825 static inline struct file *get_file(struct file *f)
827 atomic_long_inc(&f->f_count);
830 #define fput_atomic(x) atomic_long_add_unless(&(x)->f_count, -1, 1)
831 #define file_count(x) atomic_long_read(&(x)->f_count)
833 #ifdef CONFIG_DEBUG_WRITECOUNT
834 static inline void file_take_write(struct file *f)
836 WARN_ON(f->f_mnt_write_state != 0);
837 f->f_mnt_write_state = FILE_MNT_WRITE_TAKEN;
839 static inline void file_release_write(struct file *f)
841 f->f_mnt_write_state |= FILE_MNT_WRITE_RELEASED;
843 static inline void file_reset_write(struct file *f)
845 f->f_mnt_write_state = 0;
847 static inline void file_check_state(struct file *f)
850 * At this point, either both or neither of these bits
853 WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN);
854 WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_RELEASED);
856 static inline int file_check_writeable(struct file *f)
858 if (f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN)
860 printk(KERN_WARNING "writeable file with no "
861 "mnt_want_write()\n");
865 #else /* !CONFIG_DEBUG_WRITECOUNT */
866 static inline void file_take_write(struct file *filp) {}
867 static inline void file_release_write(struct file *filp) {}
868 static inline void file_reset_write(struct file *filp) {}
869 static inline void file_check_state(struct file *filp) {}
870 static inline int file_check_writeable(struct file *filp)
874 #endif /* CONFIG_DEBUG_WRITECOUNT */
876 #define MAX_NON_LFS ((1UL<<31) - 1)
878 /* Page cache limit. The filesystems should put that into their s_maxbytes
879 limits, otherwise bad things can happen in VM. */
880 #if BITS_PER_LONG==32
881 #define MAX_LFS_FILESIZE (((loff_t)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
882 #elif BITS_PER_LONG==64
883 #define MAX_LFS_FILESIZE ((loff_t)0x7fffffffffffffffLL)
888 #define FL_DELEG 4 /* NFSv4 delegation */
889 #define FL_ACCESS 8 /* not trying to lock, just looking */
890 #define FL_EXISTS 16 /* when unlocking, test for existence */
891 #define FL_LEASE 32 /* lease held on this file */
892 #define FL_CLOSE 64 /* unlock on close */
893 #define FL_SLEEP 128 /* A blocking lock */
894 #define FL_DOWNGRADE_PENDING 256 /* Lease is being downgraded */
895 #define FL_UNLOCK_PENDING 512 /* Lease is being broken */
898 * Special return value from posix_lock_file() and vfs_lock_file() for
899 * asynchronous locking.
901 #define FILE_LOCK_DEFERRED 1
904 * The POSIX file lock owner is determined by
905 * the "struct files_struct" in the thread group
906 * (or NULL for no owner - BSD locks).
908 * Lockd stuffs a "host" pointer into this.
910 typedef struct files_struct *fl_owner_t;
912 struct file_lock_operations {
913 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
914 void (*fl_release_private)(struct file_lock *);
917 struct lock_manager_operations {
918 int (*lm_compare_owner)(struct file_lock *, struct file_lock *);
919 unsigned long (*lm_owner_key)(struct file_lock *);
920 void (*lm_notify)(struct file_lock *); /* unblock callback */
921 int (*lm_grant)(struct file_lock *, struct file_lock *, int);
922 void (*lm_break)(struct file_lock *);
923 int (*lm_change)(struct file_lock **, int);
926 struct lock_manager {
927 struct list_head list;
931 void locks_start_grace(struct net *, struct lock_manager *);
932 void locks_end_grace(struct lock_manager *);
933 int locks_in_grace(struct net *);
935 /* that will die - we need it for nfs_lock_info */
936 #include <linux/nfs_fs_i.h>
939 * struct file_lock represents a generic "file lock". It's used to represent
940 * POSIX byte range locks, BSD (flock) locks, and leases. It's important to
941 * note that the same struct is used to represent both a request for a lock and
942 * the lock itself, but the same object is never used for both.
944 * FIXME: should we create a separate "struct lock_request" to help distinguish
947 * The i_flock list is ordered by:
949 * 1) lock type -- FL_LEASEs first, then FL_FLOCK, and finally FL_POSIX
951 * 3) lock range start
954 * Obviously, the last two criteria only matter for POSIX locks.
957 struct file_lock *fl_next; /* singly linked list for this inode */
958 struct hlist_node fl_link; /* node in global lists */
959 struct list_head fl_block; /* circular list of blocked processes */
961 unsigned int fl_flags;
962 unsigned char fl_type;
964 int fl_link_cpu; /* what cpu's list is this on? */
965 struct pid *fl_nspid;
966 wait_queue_head_t fl_wait;
967 struct file *fl_file;
971 struct fasync_struct * fl_fasync; /* for lease break notifications */
972 /* for lease breaks: */
973 unsigned long fl_break_time;
974 unsigned long fl_downgrade_time;
976 const struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
977 const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
979 struct nfs_lock_info nfs_fl;
980 struct nfs4_lock_info nfs4_fl;
982 struct list_head link; /* link in AFS vnode's pending_locks list */
983 int state; /* state of grant or error if -ve */
988 /* The following constant reflects the upper bound of the file/locking space */
990 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
991 #define OFFSET_MAX INT_LIMIT(loff_t)
992 #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
995 #include <linux/fcntl.h>
997 extern void send_sigio(struct fown_struct *fown, int fd, int band);
999 #ifdef CONFIG_FILE_LOCKING
1000 extern int fcntl_getlk(struct file *, struct flock __user *);
1001 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
1002 struct flock __user *);
1004 #if BITS_PER_LONG == 32
1005 extern int fcntl_getlk64(struct file *, struct flock64 __user *);
1006 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
1007 struct flock64 __user *);
1010 extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
1011 extern int fcntl_getlease(struct file *filp);
1014 void locks_free_lock(struct file_lock *fl);
1015 extern void locks_init_lock(struct file_lock *);
1016 extern struct file_lock * locks_alloc_lock(void);
1017 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
1018 extern void __locks_copy_lock(struct file_lock *, const struct file_lock *);
1019 extern void locks_remove_posix(struct file *, fl_owner_t);
1020 extern void locks_remove_flock(struct file *);
1021 extern void locks_release_private(struct file_lock *);
1022 extern void posix_test_lock(struct file *, struct file_lock *);
1023 extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
1024 extern int posix_lock_file_wait(struct file *, struct file_lock *);
1025 extern int posix_unblock_lock(struct file_lock *);
1026 extern int vfs_test_lock(struct file *, struct file_lock *);
1027 extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
1028 extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
1029 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
1030 extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int type);
1031 extern void lease_get_mtime(struct inode *, struct timespec *time);
1032 extern int generic_setlease(struct file *, long, struct file_lock **);
1033 extern int vfs_setlease(struct file *, long, struct file_lock **);
1034 extern int lease_modify(struct file_lock **, int);
1035 extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
1036 extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
1037 #else /* !CONFIG_FILE_LOCKING */
1038 static inline int fcntl_getlk(struct file *file, struct flock __user *user)
1043 static inline int fcntl_setlk(unsigned int fd, struct file *file,
1044 unsigned int cmd, struct flock __user *user)
1049 #if BITS_PER_LONG == 32
1050 static inline int fcntl_getlk64(struct file *file, struct flock64 __user *user)
1055 static inline int fcntl_setlk64(unsigned int fd, struct file *file,
1056 unsigned int cmd, struct flock64 __user *user)
1061 static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
1066 static inline int fcntl_getlease(struct file *filp)
1071 static inline void locks_init_lock(struct file_lock *fl)
1076 static inline void __locks_copy_lock(struct file_lock *new, struct file_lock *fl)
1081 static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
1086 static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
1091 static inline void locks_remove_flock(struct file *filp)
1096 static inline void posix_test_lock(struct file *filp, struct file_lock *fl)
1101 static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
1102 struct file_lock *conflock)
1107 static inline int posix_lock_file_wait(struct file *filp, struct file_lock *fl)
1112 static inline int posix_unblock_lock(struct file_lock *waiter)
1117 static inline int vfs_test_lock(struct file *filp, struct file_lock *fl)
1122 static inline int vfs_lock_file(struct file *filp, unsigned int cmd,
1123 struct file_lock *fl, struct file_lock *conf)
1128 static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
1133 static inline int flock_lock_file_wait(struct file *filp,
1134 struct file_lock *request)
1139 static inline int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
1144 static inline void lease_get_mtime(struct inode *inode, struct timespec *time)
1149 static inline int generic_setlease(struct file *filp, long arg,
1150 struct file_lock **flp)
1155 static inline int vfs_setlease(struct file *filp, long arg,
1156 struct file_lock **lease)
1161 static inline int lease_modify(struct file_lock **before, int arg)
1166 static inline int lock_may_read(struct inode *inode, loff_t start,
1172 static inline int lock_may_write(struct inode *inode, loff_t start,
1177 #endif /* !CONFIG_FILE_LOCKING */
1180 struct fasync_struct {
1184 struct fasync_struct *fa_next; /* singly linked list */
1185 struct file *fa_file;
1186 struct rcu_head fa_rcu;
1189 #define FASYNC_MAGIC 0x4601
1191 /* SMP safe fasync helpers: */
1192 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1193 extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
1194 extern int fasync_remove_entry(struct file *, struct fasync_struct **);
1195 extern struct fasync_struct *fasync_alloc(void);
1196 extern void fasync_free(struct fasync_struct *);
1198 /* can be called from interrupts */
1199 extern void kill_fasync(struct fasync_struct **, int, int);
1201 extern int __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1202 extern int f_setown(struct file *filp, unsigned long arg, int force);
1203 extern void f_delown(struct file *filp);
1204 extern pid_t f_getown(struct file *filp);
1205 extern int send_sigurg(struct fown_struct *fown);
1213 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1214 #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1215 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1216 #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1217 #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1219 extern struct list_head super_blocks;
1220 extern spinlock_t sb_lock;
1222 /* Possible states of 'frozen' field */
1224 SB_UNFROZEN = 0, /* FS is unfrozen */
1225 SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */
1226 SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */
1227 SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop
1228 * internal threads if needed) */
1229 SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */
1232 #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1235 /* Counters for counting writers at each level */
1236 struct percpu_counter counter[SB_FREEZE_LEVELS];
1237 wait_queue_head_t wait; /* queue for waiting for
1238 writers / faults to finish */
1239 int frozen; /* Is sb frozen? */
1240 wait_queue_head_t wait_unfrozen; /* queue for waiting for
1242 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1243 struct lockdep_map lock_map[SB_FREEZE_LEVELS];
1247 struct super_block {
1248 struct list_head s_list; /* Keep this first */
1249 dev_t s_dev; /* search index; _not_ kdev_t */
1250 unsigned char s_blocksize_bits;
1251 unsigned long s_blocksize;
1252 loff_t s_maxbytes; /* Max file size */
1253 struct file_system_type *s_type;
1254 const struct super_operations *s_op;
1255 const struct dquot_operations *dq_op;
1256 const struct quotactl_ops *s_qcop;
1257 const struct export_operations *s_export_op;
1258 unsigned long s_flags;
1259 unsigned long s_magic;
1260 struct dentry *s_root;
1261 struct rw_semaphore s_umount;
1264 #ifdef CONFIG_SECURITY
1267 const struct xattr_handler **s_xattr;
1269 struct list_head s_inodes; /* all inodes */
1270 struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */
1271 struct list_head s_mounts; /* list of mounts; _not_ for fs use */
1272 struct block_device *s_bdev;
1273 struct backing_dev_info *s_bdi;
1274 struct mtd_info *s_mtd;
1275 struct hlist_node s_instances;
1276 struct quota_info s_dquot; /* Diskquota specific options */
1278 struct sb_writers s_writers;
1280 char s_id[32]; /* Informational name */
1281 u8 s_uuid[16]; /* UUID */
1283 void *s_fs_info; /* Filesystem private info */
1284 unsigned int s_max_links;
1287 /* Granularity of c/m/atime in ns.
1288 Cannot be worse than a second */
1292 * The next field is for VFS *only*. No filesystems have any business
1293 * even looking at it. You had been warned.
1295 struct mutex s_vfs_rename_mutex; /* Kludge */
1298 * Filesystem subtype. If non-empty the filesystem type field
1299 * in /proc/mounts will be "type.subtype"
1304 * Saved mount options for lazy filesystems using
1305 * generic_show_options()
1307 char __rcu *s_options;
1308 const struct dentry_operations *s_d_op; /* default d_op for dentries */
1311 * Saved pool identifier for cleancache (-1 means none)
1313 int cleancache_poolid;
1315 struct shrinker s_shrink; /* per-sb shrinker handle */
1317 /* Number of inodes with nlink == 0 but still referenced */
1318 atomic_long_t s_remove_count;
1320 /* Being remounted read-only */
1321 int s_readonly_remount;
1323 /* AIO completions deferred from interrupt context */
1324 struct workqueue_struct *s_dio_done_wq;
1327 * Keep the lru lists last in the structure so they always sit on their
1328 * own individual cachelines.
1330 struct list_lru s_dentry_lru ____cacheline_aligned_in_smp;
1331 struct list_lru s_inode_lru ____cacheline_aligned_in_smp;
1332 struct rcu_head rcu;
1335 extern struct timespec current_fs_time(struct super_block *sb);
1338 * Snapshotting support.
1341 void __sb_end_write(struct super_block *sb, int level);
1342 int __sb_start_write(struct super_block *sb, int level, bool wait);
1345 * sb_end_write - drop write access to a superblock
1346 * @sb: the super we wrote to
1348 * Decrement number of writers to the filesystem. Wake up possible waiters
1349 * wanting to freeze the filesystem.
1351 static inline void sb_end_write(struct super_block *sb)
1353 __sb_end_write(sb, SB_FREEZE_WRITE);
1357 * sb_end_pagefault - drop write access to a superblock from a page fault
1358 * @sb: the super we wrote to
1360 * Decrement number of processes handling write page fault to the filesystem.
1361 * Wake up possible waiters wanting to freeze the filesystem.
1363 static inline void sb_end_pagefault(struct super_block *sb)
1365 __sb_end_write(sb, SB_FREEZE_PAGEFAULT);
1369 * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1370 * @sb: the super we wrote to
1372 * Decrement fs-internal number of writers to the filesystem. Wake up possible
1373 * waiters wanting to freeze the filesystem.
1375 static inline void sb_end_intwrite(struct super_block *sb)
1377 __sb_end_write(sb, SB_FREEZE_FS);
1381 * sb_start_write - get write access to a superblock
1382 * @sb: the super we write to
1384 * When a process wants to write data or metadata to a file system (i.e. dirty
1385 * a page or an inode), it should embed the operation in a sb_start_write() -
1386 * sb_end_write() pair to get exclusion against file system freezing. This
1387 * function increments number of writers preventing freezing. If the file
1388 * system is already frozen, the function waits until the file system is
1391 * Since freeze protection behaves as a lock, users have to preserve
1392 * ordering of freeze protection and other filesystem locks. Generally,
1393 * freeze protection should be the outermost lock. In particular, we have:
1396 * -> i_mutex (write path, truncate, directory ops, ...)
1397 * -> s_umount (freeze_super, thaw_super)
1399 static inline void sb_start_write(struct super_block *sb)
1401 __sb_start_write(sb, SB_FREEZE_WRITE, true);
1404 static inline int sb_start_write_trylock(struct super_block *sb)
1406 return __sb_start_write(sb, SB_FREEZE_WRITE, false);
1410 * sb_start_pagefault - get write access to a superblock from a page fault
1411 * @sb: the super we write to
1413 * When a process starts handling write page fault, it should embed the
1414 * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1415 * exclusion against file system freezing. This is needed since the page fault
1416 * is going to dirty a page. This function increments number of running page
1417 * faults preventing freezing. If the file system is already frozen, the
1418 * function waits until the file system is thawed.
1420 * Since page fault freeze protection behaves as a lock, users have to preserve
1421 * ordering of freeze protection and other filesystem locks. It is advised to
1422 * put sb_start_pagefault() close to mmap_sem in lock ordering. Page fault
1423 * handling code implies lock dependency:
1426 * -> sb_start_pagefault
1428 static inline void sb_start_pagefault(struct super_block *sb)
1430 __sb_start_write(sb, SB_FREEZE_PAGEFAULT, true);
1434 * sb_start_intwrite - get write access to a superblock for internal fs purposes
1435 * @sb: the super we write to
1437 * This is the third level of protection against filesystem freezing. It is
1438 * free for use by a filesystem. The only requirement is that it must rank
1439 * below sb_start_pagefault.
1441 * For example filesystem can call sb_start_intwrite() when starting a
1442 * transaction which somewhat eases handling of freezing for internal sources
1443 * of filesystem changes (internal fs threads, discarding preallocation on file
1446 static inline void sb_start_intwrite(struct super_block *sb)
1448 __sb_start_write(sb, SB_FREEZE_FS, true);
1452 extern bool inode_owner_or_capable(const struct inode *inode);
1455 * VFS helper functions..
1457 extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
1458 extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
1459 extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
1460 extern int vfs_symlink(struct inode *, struct dentry *, const char *);
1461 extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
1462 extern int vfs_rmdir(struct inode *, struct dentry *);
1463 extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
1464 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **);
1467 * VFS dentry helper functions.
1469 extern void dentry_unhash(struct dentry *dentry);
1472 * VFS file helper functions.
1474 extern void inode_init_owner(struct inode *inode, const struct inode *dir,
1477 * VFS FS_IOC_FIEMAP helper definitions.
1479 struct fiemap_extent_info {
1480 unsigned int fi_flags; /* Flags as passed from user */
1481 unsigned int fi_extents_mapped; /* Number of mapped extents */
1482 unsigned int fi_extents_max; /* Size of fiemap_extent array */
1483 struct fiemap_extent __user *fi_extents_start; /* Start of
1484 fiemap_extent array */
1486 int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
1487 u64 phys, u64 len, u32 flags);
1488 int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
1493 * NOTE! These match bits 12..15 of stat.st_mode
1494 * (ie "(i_mode >> 12) & 15").
1496 #define DT_UNKNOWN 0
1507 * This is the "filldir" function type, used by readdir() to let
1508 * the kernel specify what kind of dirent layout it wants to have.
1509 * This allows the kernel to read directories into kernel space or
1510 * to have different dirent layouts depending on the binary type.
1512 typedef int (*filldir_t)(void *, const char *, int, loff_t, u64, unsigned);
1513 struct dir_context {
1514 const filldir_t actor;
1518 struct block_device_operations;
1520 /* These macros are for out of kernel modules to test that
1521 * the kernel supports the unlocked_ioctl and compat_ioctl
1522 * fields in struct file_operations. */
1523 #define HAVE_COMPAT_IOCTL 1
1524 #define HAVE_UNLOCKED_IOCTL 1
1526 struct file_operations {
1527 struct module *owner;
1528 loff_t (*llseek) (struct file *, loff_t, int);
1529 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1530 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1531 ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1532 ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1533 int (*iterate) (struct file *, struct dir_context *);
1534 unsigned int (*poll) (struct file *, struct poll_table_struct *);
1535 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1536 long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1537 int (*mmap) (struct file *, struct vm_area_struct *);
1538 int (*open) (struct inode *, struct file *);
1539 int (*flush) (struct file *, fl_owner_t id);
1540 int (*release) (struct inode *, struct file *);
1541 int (*fsync) (struct file *, loff_t, loff_t, int datasync);
1542 int (*aio_fsync) (struct kiocb *, int datasync);
1543 int (*fasync) (int, struct file *, int);
1544 int (*lock) (struct file *, int, struct file_lock *);
1545 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1546 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1547 int (*check_flags)(int);
1548 int (*flock) (struct file *, int, struct file_lock *);
1549 ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1550 ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1551 int (*setlease)(struct file *, long, struct file_lock **);
1552 long (*fallocate)(struct file *file, int mode, loff_t offset,
1554 int (*show_fdinfo)(struct seq_file *m, struct file *f);
1557 struct inode_operations {
1558 struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
1559 void * (*follow_link) (struct dentry *, struct nameidata *);
1560 int (*permission) (struct inode *, int);
1561 struct posix_acl * (*get_acl)(struct inode *, int);
1563 int (*readlink) (struct dentry *, char __user *,int);
1564 void (*put_link) (struct dentry *, struct nameidata *, void *);
1566 int (*create) (struct inode *,struct dentry *, umode_t, bool);
1567 int (*link) (struct dentry *,struct inode *,struct dentry *);
1568 int (*unlink) (struct inode *,struct dentry *);
1569 int (*symlink) (struct inode *,struct dentry *,const char *);
1570 int (*mkdir) (struct inode *,struct dentry *,umode_t);
1571 int (*rmdir) (struct inode *,struct dentry *);
1572 int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
1573 int (*rename) (struct inode *, struct dentry *,
1574 struct inode *, struct dentry *);
1575 int (*setattr) (struct dentry *, struct iattr *);
1576 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
1577 int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
1578 ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
1579 ssize_t (*listxattr) (struct dentry *, char *, size_t);
1580 int (*removexattr) (struct dentry *, const char *);
1581 int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
1583 int (*update_time)(struct inode *, struct timespec *, int);
1584 int (*atomic_open)(struct inode *, struct dentry *,
1585 struct file *, unsigned open_flag,
1586 umode_t create_mode, int *opened);
1587 int (*tmpfile) (struct inode *, struct dentry *, umode_t);
1588 int (*set_acl)(struct inode *, struct posix_acl *, int);
1589 } ____cacheline_aligned;
1591 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
1592 unsigned long nr_segs, unsigned long fast_segs,
1593 struct iovec *fast_pointer,
1594 struct iovec **ret_pointer);
1596 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1597 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1598 extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
1599 unsigned long, loff_t *);
1600 extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
1601 unsigned long, loff_t *);
1603 struct super_operations {
1604 struct inode *(*alloc_inode)(struct super_block *sb);
1605 void (*destroy_inode)(struct inode *);
1607 void (*dirty_inode) (struct inode *, int flags);
1608 int (*write_inode) (struct inode *, struct writeback_control *wbc);
1609 int (*drop_inode) (struct inode *);
1610 void (*evict_inode) (struct inode *);
1611 void (*put_super) (struct super_block *);
1612 int (*sync_fs)(struct super_block *sb, int wait);
1613 int (*freeze_fs) (struct super_block *);
1614 int (*unfreeze_fs) (struct super_block *);
1615 int (*statfs) (struct dentry *, struct kstatfs *);
1616 int (*remount_fs) (struct super_block *, int *, char *);
1617 void (*umount_begin) (struct super_block *);
1619 int (*show_options)(struct seq_file *, struct dentry *);
1620 int (*show_devname)(struct seq_file *, struct dentry *);
1621 int (*show_path)(struct seq_file *, struct dentry *);
1622 int (*show_stats)(struct seq_file *, struct dentry *);
1624 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1625 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1627 int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
1628 long (*nr_cached_objects)(struct super_block *, int);
1629 long (*free_cached_objects)(struct super_block *, long, int);
1633 * Inode flags - they have no relation to superblock flags now
1635 #define S_SYNC 1 /* Writes are synced at once */
1636 #define S_NOATIME 2 /* Do not update access times */
1637 #define S_APPEND 4 /* Append-only file */
1638 #define S_IMMUTABLE 8 /* Immutable file */
1639 #define S_DEAD 16 /* removed, but still open directory */
1640 #define S_NOQUOTA 32 /* Inode is not counted to quota */
1641 #define S_DIRSYNC 64 /* Directory modifications are synchronous */
1642 #define S_NOCMTIME 128 /* Do not update file c/mtime */
1643 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
1644 #define S_PRIVATE 512 /* Inode is fs-internal */
1645 #define S_IMA 1024 /* Inode has an associated IMA struct */
1646 #define S_AUTOMOUNT 2048 /* Automount/referral quasi-directory */
1647 #define S_NOSEC 4096 /* no suid or xattr security attributes */
1650 * Note that nosuid etc flags are inode-specific: setting some file-system
1651 * flags just means all the inodes inherit those flags by default. It might be
1652 * possible to override it selectively if you really wanted to with some
1653 * ioctl() that is not currently implemented.
1655 * Exception: MS_RDONLY is always applied to the entire file system.
1657 * Unfortunately, it is possible to change a filesystems flags with it mounted
1658 * with files in use. This means that all of the inodes will not have their
1659 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
1660 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
1662 #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
1664 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
1665 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
1666 ((inode)->i_flags & S_SYNC))
1667 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
1668 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
1669 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
1670 #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
1671 #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION)
1673 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
1674 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
1675 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
1676 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
1678 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
1679 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
1680 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
1681 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
1682 #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
1683 #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
1684 #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
1687 * Inode state bits. Protected by inode->i_lock
1689 * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
1690 * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
1692 * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
1693 * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
1694 * various stages of removing an inode.
1696 * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
1698 * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
1699 * fdatasync(). i_atime is the usual cause.
1700 * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
1701 * these changes separately from I_DIRTY_SYNC so that we
1702 * don't have to write inode on fdatasync() when only
1703 * mtime has changed in it.
1704 * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
1705 * I_NEW Serves as both a mutex and completion notification.
1706 * New inodes set I_NEW. If two processes both create
1707 * the same inode, one of them will release its inode and
1708 * wait for I_NEW to be released before returning.
1709 * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
1710 * also cause waiting on I_NEW, without I_NEW actually
1711 * being set. find_inode() uses this to prevent returning
1712 * nearly-dead inodes.
1713 * I_WILL_FREE Must be set when calling write_inode_now() if i_count
1714 * is zero. I_FREEING must be set when I_WILL_FREE is
1716 * I_FREEING Set when inode is about to be freed but still has dirty
1717 * pages or buffers attached or the inode itself is still
1719 * I_CLEAR Added by clear_inode(). In this state the inode is
1720 * clean and can be destroyed. Inode keeps I_FREEING.
1722 * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
1723 * prohibited for many purposes. iget() must wait for
1724 * the inode to be completely released, then create it
1725 * anew. Other functions will just ignore such inodes,
1726 * if appropriate. I_NEW is used for waiting.
1728 * I_SYNC Writeback of inode is running. The bit is set during
1729 * data writeback, and cleared with a wakeup on the bit
1730 * address once it is done. The bit is also used to pin
1731 * the inode in memory for flusher thread.
1733 * I_REFERENCED Marks the inode as recently references on the LRU list.
1735 * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
1737 * Q: What is the difference between I_WILL_FREE and I_FREEING?
1739 #define I_DIRTY_SYNC (1 << 0)
1740 #define I_DIRTY_DATASYNC (1 << 1)
1741 #define I_DIRTY_PAGES (1 << 2)
1743 #define I_NEW (1 << __I_NEW)
1744 #define I_WILL_FREE (1 << 4)
1745 #define I_FREEING (1 << 5)
1746 #define I_CLEAR (1 << 6)
1748 #define I_SYNC (1 << __I_SYNC)
1749 #define I_REFERENCED (1 << 8)
1750 #define __I_DIO_WAKEUP 9
1751 #define I_DIO_WAKEUP (1 << I_DIO_WAKEUP)
1752 #define I_LINKABLE (1 << 10)
1754 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1756 extern void __mark_inode_dirty(struct inode *, int);
1757 static inline void mark_inode_dirty(struct inode *inode)
1759 __mark_inode_dirty(inode, I_DIRTY);
1762 static inline void mark_inode_dirty_sync(struct inode *inode)
1764 __mark_inode_dirty(inode, I_DIRTY_SYNC);
1767 extern void inc_nlink(struct inode *inode);
1768 extern void drop_nlink(struct inode *inode);
1769 extern void clear_nlink(struct inode *inode);
1770 extern void set_nlink(struct inode *inode, unsigned int nlink);
1772 static inline void inode_inc_link_count(struct inode *inode)
1775 mark_inode_dirty(inode);
1778 static inline void inode_dec_link_count(struct inode *inode)
1781 mark_inode_dirty(inode);
1785 * inode_inc_iversion - increments i_version
1786 * @inode: inode that need to be updated
1788 * Every time the inode is modified, the i_version field will be incremented.
1789 * The filesystem has to be mounted with i_version flag
1792 static inline void inode_inc_iversion(struct inode *inode)
1794 spin_lock(&inode->i_lock);
1796 spin_unlock(&inode->i_lock);
1799 enum file_time_flags {
1806 extern void touch_atime(const struct path *);
1807 static inline void file_accessed(struct file *file)
1809 if (!(file->f_flags & O_NOATIME))
1810 touch_atime(&file->f_path);
1813 int sync_inode(struct inode *inode, struct writeback_control *wbc);
1814 int sync_inode_metadata(struct inode *inode, int wait);
1816 struct file_system_type {
1819 #define FS_REQUIRES_DEV 1
1820 #define FS_BINARY_MOUNTDATA 2
1821 #define FS_HAS_SUBTYPE 4
1822 #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
1823 #define FS_USERNS_DEV_MOUNT 16 /* A userns mount does not imply MNT_NODEV */
1824 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
1825 struct dentry *(*mount) (struct file_system_type *, int,
1826 const char *, void *);
1827 void (*kill_sb) (struct super_block *);
1828 struct module *owner;
1829 struct file_system_type * next;
1830 struct hlist_head fs_supers;
1832 struct lock_class_key s_lock_key;
1833 struct lock_class_key s_umount_key;
1834 struct lock_class_key s_vfs_rename_key;
1835 struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
1837 struct lock_class_key i_lock_key;
1838 struct lock_class_key i_mutex_key;
1839 struct lock_class_key i_mutex_dir_key;
1842 #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
1844 extern struct dentry *mount_ns(struct file_system_type *fs_type, int flags,
1845 void *data, int (*fill_super)(struct super_block *, void *, int));
1846 extern struct dentry *mount_bdev(struct file_system_type *fs_type,
1847 int flags, const char *dev_name, void *data,
1848 int (*fill_super)(struct super_block *, void *, int));
1849 extern struct dentry *mount_single(struct file_system_type *fs_type,
1850 int flags, void *data,
1851 int (*fill_super)(struct super_block *, void *, int));
1852 extern struct dentry *mount_nodev(struct file_system_type *fs_type,
1853 int flags, void *data,
1854 int (*fill_super)(struct super_block *, void *, int));
1855 extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
1856 void generic_shutdown_super(struct super_block *sb);
1857 void kill_block_super(struct super_block *sb);
1858 void kill_anon_super(struct super_block *sb);
1859 void kill_litter_super(struct super_block *sb);
1860 void deactivate_super(struct super_block *sb);
1861 void deactivate_locked_super(struct super_block *sb);
1862 int set_anon_super(struct super_block *s, void *data);
1863 int get_anon_bdev(dev_t *);
1864 void free_anon_bdev(dev_t);
1865 struct super_block *sget(struct file_system_type *type,
1866 int (*test)(struct super_block *,void *),
1867 int (*set)(struct super_block *,void *),
1868 int flags, void *data);
1869 extern struct dentry *mount_pseudo(struct file_system_type *, char *,
1870 const struct super_operations *ops,
1871 const struct dentry_operations *dops,
1874 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
1875 #define fops_get(fops) \
1876 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
1877 #define fops_put(fops) \
1878 do { if (fops) module_put((fops)->owner); } while(0)
1880 * This one is to be used *ONLY* from ->open() instances.
1881 * fops must be non-NULL, pinned down *and* module dependencies
1882 * should be sufficient to pin the caller down as well.
1884 #define replace_fops(f, fops) \
1886 struct file *__file = (f); \
1887 fops_put(__file->f_op); \
1888 BUG_ON(!(__file->f_op = (fops))); \
1891 extern int register_filesystem(struct file_system_type *);
1892 extern int unregister_filesystem(struct file_system_type *);
1893 extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
1894 #define kern_mount(type) kern_mount_data(type, NULL)
1895 extern void kern_unmount(struct vfsmount *mnt);
1896 extern int may_umount_tree(struct vfsmount *);
1897 extern int may_umount(struct vfsmount *);
1898 extern long do_mount(const char *, const char *, const char *, unsigned long, void *);
1899 extern struct vfsmount *collect_mounts(struct path *);
1900 extern void drop_collected_mounts(struct vfsmount *);
1901 extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
1903 extern int vfs_statfs(struct path *, struct kstatfs *);
1904 extern int user_statfs(const char __user *, struct kstatfs *);
1905 extern int fd_statfs(int, struct kstatfs *);
1906 extern int vfs_ustat(dev_t, struct kstatfs *);
1907 extern int freeze_super(struct super_block *super);
1908 extern int thaw_super(struct super_block *super);
1909 extern bool our_mnt(struct vfsmount *mnt);
1910 extern bool fs_fully_visible(struct file_system_type *);
1912 extern int current_umask(void);
1914 extern void ihold(struct inode * inode);
1915 extern void iput(struct inode *);
1918 extern struct kobject *fs_kobj;
1920 #define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK)
1922 #define FLOCK_VERIFY_READ 1
1923 #define FLOCK_VERIFY_WRITE 2
1925 #ifdef CONFIG_FILE_LOCKING
1926 extern int locks_mandatory_locked(struct inode *);
1927 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
1930 * Candidates for mandatory locking have the setgid bit set
1931 * but no group execute bit - an otherwise meaningless combination.
1934 static inline int __mandatory_lock(struct inode *ino)
1936 return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
1940 * ... and these candidates should be on MS_MANDLOCK mounted fs,
1941 * otherwise these will be advisory locks
1944 static inline int mandatory_lock(struct inode *ino)
1946 return IS_MANDLOCK(ino) && __mandatory_lock(ino);
1949 static inline int locks_verify_locked(struct inode *inode)
1951 if (mandatory_lock(inode))
1952 return locks_mandatory_locked(inode);
1956 static inline int locks_verify_truncate(struct inode *inode,
1960 if (inode->i_flock && mandatory_lock(inode))
1961 return locks_mandatory_area(
1962 FLOCK_VERIFY_WRITE, inode, filp,
1963 size < inode->i_size ? size : inode->i_size,
1964 (size < inode->i_size ? inode->i_size - size
1965 : size - inode->i_size)
1970 static inline int break_lease(struct inode *inode, unsigned int mode)
1973 return __break_lease(inode, mode, FL_LEASE);
1977 static inline int break_deleg(struct inode *inode, unsigned int mode)
1980 return __break_lease(inode, mode, FL_DELEG);
1984 static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
1988 ret = break_deleg(inode, O_WRONLY|O_NONBLOCK);
1989 if (ret == -EWOULDBLOCK && delegated_inode) {
1990 *delegated_inode = inode;
1996 static inline int break_deleg_wait(struct inode **delegated_inode)
2000 ret = break_deleg(*delegated_inode, O_WRONLY);
2001 iput(*delegated_inode);
2002 *delegated_inode = NULL;
2006 #else /* !CONFIG_FILE_LOCKING */
2007 static inline int locks_mandatory_locked(struct inode *inode)
2012 static inline int locks_mandatory_area(int rw, struct inode *inode,
2013 struct file *filp, loff_t offset,
2019 static inline int __mandatory_lock(struct inode *inode)
2024 static inline int mandatory_lock(struct inode *inode)
2029 static inline int locks_verify_locked(struct inode *inode)
2034 static inline int locks_verify_truncate(struct inode *inode, struct file *filp,
2040 static inline int break_lease(struct inode *inode, unsigned int mode)
2045 static inline int break_deleg(struct inode *inode, unsigned int mode)
2050 static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
2055 static inline int break_deleg_wait(struct inode **delegated_inode)
2061 #endif /* CONFIG_FILE_LOCKING */
2066 const char *name; /* pointer to actual string */
2067 const __user char *uptr; /* original userland pointer */
2068 struct audit_names *aname;
2069 bool separate; /* should "name" be freed? */
2072 extern long vfs_truncate(struct path *, loff_t);
2073 extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
2075 extern int do_fallocate(struct file *file, int mode, loff_t offset,
2077 extern long do_sys_open(int dfd, const char __user *filename, int flags,
2079 extern struct file *file_open_name(struct filename *, int, umode_t);
2080 extern struct file *filp_open(const char *, int, umode_t);
2081 extern struct file *file_open_root(struct dentry *, struct vfsmount *,
2083 extern struct file * dentry_open(const struct path *, int, const struct cred *);
2084 extern int filp_close(struct file *, fl_owner_t id);
2086 extern struct filename *getname(const char __user *);
2087 extern struct filename *getname_kernel(const char *);
2093 extern int finish_open(struct file *file, struct dentry *dentry,
2094 int (*open)(struct inode *, struct file *),
2096 extern int finish_no_open(struct file *file, struct dentry *dentry);
2100 extern int ioctl_preallocate(struct file *filp, void __user *argp);
2103 extern void __init vfs_caches_init_early(void);
2104 extern void __init vfs_caches_init(unsigned long);
2106 extern struct kmem_cache *names_cachep;
2108 extern void final_putname(struct filename *name);
2110 #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
2111 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2112 #ifndef CONFIG_AUDITSYSCALL
2113 #define putname(name) final_putname(name)
2115 extern void putname(struct filename *name);
2119 extern int register_blkdev(unsigned int, const char *);
2120 extern void unregister_blkdev(unsigned int, const char *);
2121 extern struct block_device *bdget(dev_t);
2122 extern struct block_device *bdgrab(struct block_device *bdev);
2123 extern void bd_set_size(struct block_device *, loff_t size);
2124 extern void bd_forget(struct inode *inode);
2125 extern void bdput(struct block_device *);
2126 extern void invalidate_bdev(struct block_device *);
2127 extern void iterate_bdevs(void (*)(struct block_device *, void *), void *);
2128 extern int sync_blockdev(struct block_device *bdev);
2129 extern void kill_bdev(struct block_device *);
2130 extern struct super_block *freeze_bdev(struct block_device *);
2131 extern void emergency_thaw_all(void);
2132 extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
2133 extern int fsync_bdev(struct block_device *);
2134 extern int sb_is_blkdev_sb(struct super_block *sb);
2136 static inline void bd_forget(struct inode *inode) {}
2137 static inline int sync_blockdev(struct block_device *bdev) { return 0; }
2138 static inline void kill_bdev(struct block_device *bdev) {}
2139 static inline void invalidate_bdev(struct block_device *bdev) {}
2141 static inline struct super_block *freeze_bdev(struct block_device *sb)
2146 static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
2151 static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg)
2155 static inline int sb_is_blkdev_sb(struct super_block *sb)
2160 extern int sync_filesystem(struct super_block *);
2161 extern const struct file_operations def_blk_fops;
2162 extern const struct file_operations def_chr_fops;
2163 extern const struct file_operations bad_sock_fops;
2165 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
2166 extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long);
2167 extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
2168 extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
2169 extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
2171 extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
2173 extern void blkdev_put(struct block_device *bdev, fmode_t mode);
2175 extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
2176 extern void bd_unlink_disk_holder(struct block_device *bdev,
2177 struct gendisk *disk);
2179 static inline int bd_link_disk_holder(struct block_device *bdev,
2180 struct gendisk *disk)
2184 static inline void bd_unlink_disk_holder(struct block_device *bdev,
2185 struct gendisk *disk)
2192 #define CHRDEV_MAJOR_HASH_SIZE 255
2193 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
2194 extern int register_chrdev_region(dev_t, unsigned, const char *);
2195 extern int __register_chrdev(unsigned int major, unsigned int baseminor,
2196 unsigned int count, const char *name,
2197 const struct file_operations *fops);
2198 extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
2199 unsigned int count, const char *name);
2200 extern void unregister_chrdev_region(dev_t, unsigned);
2201 extern void chrdev_show(struct seq_file *,off_t);
2203 static inline int register_chrdev(unsigned int major, const char *name,
2204 const struct file_operations *fops)
2206 return __register_chrdev(major, 0, 256, name, fops);
2209 static inline void unregister_chrdev(unsigned int major, const char *name)
2211 __unregister_chrdev(major, 0, 256, name);
2214 /* fs/block_dev.c */
2215 #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
2216 #define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */
2219 #define BLKDEV_MAJOR_HASH_SIZE 255
2220 extern const char *__bdevname(dev_t, char *buffer);
2221 extern const char *bdevname(struct block_device *bdev, char *buffer);
2222 extern struct block_device *lookup_bdev(const char *);
2223 extern void blkdev_show(struct seq_file *,off_t);
2226 #define BLKDEV_MAJOR_HASH_SIZE 0
2229 extern void init_special_inode(struct inode *, umode_t, dev_t);
2231 /* Invalid inode operations -- fs/bad_inode.c */
2232 extern void make_bad_inode(struct inode *);
2233 extern int is_bad_inode(struct inode *);
2237 * return READ, READA, or WRITE
2239 #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
2242 * return data direction, READ or WRITE
2244 #define bio_data_dir(bio) ((bio)->bi_rw & 1)
2246 extern void check_disk_size_change(struct gendisk *disk,
2247 struct block_device *bdev);
2248 extern int revalidate_disk(struct gendisk *);
2249 extern int check_disk_change(struct block_device *);
2250 extern int __invalidate_device(struct block_device *, bool);
2251 extern int invalidate_partition(struct gendisk *, int);
2253 unsigned long invalidate_mapping_pages(struct address_space *mapping,
2254 pgoff_t start, pgoff_t end);
2256 static inline void invalidate_remote_inode(struct inode *inode)
2258 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2259 S_ISLNK(inode->i_mode))
2260 invalidate_mapping_pages(inode->i_mapping, 0, -1);
2262 extern int invalidate_inode_pages2(struct address_space *mapping);
2263 extern int invalidate_inode_pages2_range(struct address_space *mapping,
2264 pgoff_t start, pgoff_t end);
2265 extern int write_inode_now(struct inode *, int);
2266 extern int filemap_fdatawrite(struct address_space *);
2267 extern int filemap_flush(struct address_space *);
2268 extern int filemap_fdatawait(struct address_space *);
2269 extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
2271 extern int filemap_write_and_wait(struct address_space *mapping);
2272 extern int filemap_write_and_wait_range(struct address_space *mapping,
2273 loff_t lstart, loff_t lend);
2274 extern int __filemap_fdatawrite_range(struct address_space *mapping,
2275 loff_t start, loff_t end, int sync_mode);
2276 extern int filemap_fdatawrite_range(struct address_space *mapping,
2277 loff_t start, loff_t end);
2279 extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
2281 extern int vfs_fsync(struct file *file, int datasync);
2282 static inline int generic_write_sync(struct file *file, loff_t pos, loff_t count)
2284 if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
2286 return vfs_fsync_range(file, pos, pos + count - 1,
2287 (file->f_flags & __O_SYNC) ? 0 : 1);
2289 extern void emergency_sync(void);
2290 extern void emergency_remount(void);
2292 extern sector_t bmap(struct inode *, sector_t);
2294 extern int notify_change(struct dentry *, struct iattr *, struct inode **);
2295 extern int inode_permission(struct inode *, int);
2296 extern int generic_permission(struct inode *, int);
2298 static inline bool execute_ok(struct inode *inode)
2300 return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
2303 static inline struct inode *file_inode(struct file *f)
2308 static inline void file_start_write(struct file *file)
2310 if (!S_ISREG(file_inode(file)->i_mode))
2312 __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true);
2315 static inline bool file_start_write_trylock(struct file *file)
2317 if (!S_ISREG(file_inode(file)->i_mode))
2319 return __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, false);
2322 static inline void file_end_write(struct file *file)
2324 if (!S_ISREG(file_inode(file)->i_mode))
2326 __sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
2330 * get_write_access() gets write permission for a file.
2331 * put_write_access() releases this write permission.
2332 * This is used for regular files.
2333 * We cannot support write (and maybe mmap read-write shared) accesses and
2334 * MAP_DENYWRITE mmappings simultaneously. The i_writecount field of an inode
2335 * can have the following values:
2336 * 0: no writers, no VM_DENYWRITE mappings
2337 * < 0: (-i_writecount) vm_area_structs with VM_DENYWRITE set exist
2338 * > 0: (i_writecount) users are writing to the file.
2340 * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2341 * except for the cases where we don't hold i_writecount yet. Then we need to
2342 * use {get,deny}_write_access() - these functions check the sign and refuse
2343 * to do the change if sign is wrong.
2345 static inline int get_write_access(struct inode *inode)
2347 return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
2349 static inline int deny_write_access(struct file *file)
2351 struct inode *inode = file_inode(file);
2352 return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
2354 static inline void put_write_access(struct inode * inode)
2356 atomic_dec(&inode->i_writecount);
2358 static inline void allow_write_access(struct file *file)
2361 atomic_inc(&file_inode(file)->i_writecount);
2363 static inline bool inode_is_open_for_write(const struct inode *inode)
2365 return atomic_read(&inode->i_writecount) > 0;
2369 static inline void i_readcount_dec(struct inode *inode)
2371 BUG_ON(!atomic_read(&inode->i_readcount));
2372 atomic_dec(&inode->i_readcount);
2374 static inline void i_readcount_inc(struct inode *inode)
2376 atomic_inc(&inode->i_readcount);
2379 static inline void i_readcount_dec(struct inode *inode)
2383 static inline void i_readcount_inc(struct inode *inode)
2388 extern int do_pipe_flags(int *, int);
2390 extern int kernel_read(struct file *, loff_t, char *, unsigned long);
2391 extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
2392 extern struct file * open_exec(const char *);
2394 /* fs/dcache.c -- generic fs support functions */
2395 extern int is_subdir(struct dentry *, struct dentry *);
2396 extern int path_is_under(struct path *, struct path *);
2398 #include <linux/err.h>
2400 /* needed for stackable file system support */
2401 extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
2403 extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
2405 extern int inode_init_always(struct super_block *, struct inode *);
2406 extern void inode_init_once(struct inode *);
2407 extern void address_space_init_once(struct address_space *mapping);
2408 extern struct inode * igrab(struct inode *);
2409 extern ino_t iunique(struct super_block *, ino_t);
2410 extern int inode_needs_sync(struct inode *inode);
2411 extern int generic_delete_inode(struct inode *inode);
2412 static inline int generic_drop_inode(struct inode *inode)
2414 return !inode->i_nlink || inode_unhashed(inode);
2417 extern struct inode *ilookup5_nowait(struct super_block *sb,
2418 unsigned long hashval, int (*test)(struct inode *, void *),
2420 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
2421 int (*test)(struct inode *, void *), void *data);
2422 extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
2424 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
2425 extern struct inode * iget_locked(struct super_block *, unsigned long);
2426 extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
2427 extern int insert_inode_locked(struct inode *);
2428 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2429 extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
2431 static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
2433 extern void unlock_new_inode(struct inode *);
2434 extern unsigned int get_next_ino(void);
2436 extern void __iget(struct inode * inode);
2437 extern void iget_failed(struct inode *);
2438 extern void clear_inode(struct inode *);
2439 extern void __destroy_inode(struct inode *);
2440 extern struct inode *new_inode_pseudo(struct super_block *sb);
2441 extern struct inode *new_inode(struct super_block *sb);
2442 extern void free_inode_nonrcu(struct inode *inode);
2443 extern int should_remove_suid(struct dentry *);
2444 extern int file_remove_suid(struct file *);
2446 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
2447 static inline void insert_inode_hash(struct inode *inode)
2449 __insert_inode_hash(inode, inode->i_ino);
2452 extern void __remove_inode_hash(struct inode *);
2453 static inline void remove_inode_hash(struct inode *inode)
2455 if (!inode_unhashed(inode))
2456 __remove_inode_hash(inode);
2459 extern void inode_sb_list_add(struct inode *inode);
2462 extern void submit_bio(int, struct bio *);
2463 extern int bdev_read_only(struct block_device *);
2465 extern int set_blocksize(struct block_device *, int);
2466 extern int sb_set_blocksize(struct super_block *, int);
2467 extern int sb_min_blocksize(struct super_block *, int);
2469 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
2470 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
2471 extern int generic_file_remap_pages(struct vm_area_struct *, unsigned long addr,
2472 unsigned long size, pgoff_t pgoff);
2473 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
2474 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
2475 extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
2476 extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long,
2478 extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
2479 extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
2480 unsigned long *, loff_t, loff_t *, size_t, size_t);
2481 extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
2482 unsigned long, loff_t, loff_t *, size_t, ssize_t);
2483 extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
2484 extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
2485 extern int generic_segment_checks(const struct iovec *iov,
2486 unsigned long *nr_segs, size_t *count, int access_flags);
2488 /* fs/block_dev.c */
2489 extern ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
2490 unsigned long nr_segs, loff_t pos);
2491 extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
2493 extern void block_sync_page(struct page *page);
2496 extern ssize_t generic_file_splice_read(struct file *, loff_t *,
2497 struct pipe_inode_info *, size_t, unsigned int);
2498 extern ssize_t default_file_splice_read(struct file *, loff_t *,
2499 struct pipe_inode_info *, size_t, unsigned int);
2500 extern ssize_t generic_file_splice_write(struct pipe_inode_info *,
2501 struct file *, loff_t *, size_t, unsigned int);
2502 extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
2503 struct file *out, loff_t *, size_t len, unsigned int flags);
2506 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
2507 extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
2508 extern loff_t no_llseek(struct file *file, loff_t offset, int whence);
2509 extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
2510 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
2511 extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
2512 int whence, loff_t maxsize, loff_t eof);
2513 extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
2514 int whence, loff_t size);
2515 extern int generic_file_open(struct inode * inode, struct file * filp);
2516 extern int nonseekable_open(struct inode * inode, struct file * filp);
2518 #ifdef CONFIG_FS_XIP
2519 extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
2521 extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
2522 extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
2523 size_t len, loff_t *ppos);
2524 extern int xip_truncate_page(struct address_space *mapping, loff_t from);
2526 static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
2533 typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode,
2534 loff_t file_offset);
2537 /* need locking between buffered and direct access */
2540 /* filesystem does not support filling holes */
2541 DIO_SKIP_HOLES = 0x02,
2544 void dio_end_io(struct bio *bio, int error);
2546 ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
2547 struct block_device *bdev, const struct iovec *iov, loff_t offset,
2548 unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io,
2549 dio_submit_t submit_io, int flags);
2551 static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
2552 struct inode *inode, const struct iovec *iov, loff_t offset,
2553 unsigned long nr_segs, get_block_t get_block)
2555 return __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
2556 offset, nr_segs, get_block, NULL, NULL,
2557 DIO_LOCKING | DIO_SKIP_HOLES);
2561 void inode_dio_wait(struct inode *inode);
2562 void inode_dio_done(struct inode *inode);
2564 extern const struct file_operations generic_ro_fops;
2566 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
2568 extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
2569 extern int page_readlink(struct dentry *, char __user *, int);
2570 extern void *page_follow_link_light(struct dentry *, struct nameidata *);
2571 extern void page_put_link(struct dentry *, struct nameidata *, void *);
2572 extern int __page_symlink(struct inode *inode, const char *symname, int len,
2574 extern int page_symlink(struct inode *inode, const char *symname, int len);
2575 extern const struct inode_operations page_symlink_inode_operations;
2576 extern void kfree_put_link(struct dentry *, struct nameidata *, void *);
2577 extern int generic_readlink(struct dentry *, char __user *, int);
2578 extern void generic_fillattr(struct inode *, struct kstat *);
2579 int vfs_getattr_nosec(struct path *path, struct kstat *stat);
2580 extern int vfs_getattr(struct path *, struct kstat *);
2581 void __inode_add_bytes(struct inode *inode, loff_t bytes);
2582 void inode_add_bytes(struct inode *inode, loff_t bytes);
2583 void __inode_sub_bytes(struct inode *inode, loff_t bytes);
2584 void inode_sub_bytes(struct inode *inode, loff_t bytes);
2585 loff_t inode_get_bytes(struct inode *inode);
2586 void inode_set_bytes(struct inode *inode, loff_t bytes);
2588 extern int vfs_readdir(struct file *, filldir_t, void *);
2589 extern int iterate_dir(struct file *, struct dir_context *);
2591 extern int vfs_stat(const char __user *, struct kstat *);
2592 extern int vfs_lstat(const char __user *, struct kstat *);
2593 extern int vfs_fstat(unsigned int, struct kstat *);
2594 extern int vfs_fstatat(int , const char __user *, struct kstat *, int);
2596 extern int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
2598 extern int __generic_block_fiemap(struct inode *inode,
2599 struct fiemap_extent_info *fieinfo,
2600 loff_t start, loff_t len,
2601 get_block_t *get_block);
2602 extern int generic_block_fiemap(struct inode *inode,
2603 struct fiemap_extent_info *fieinfo, u64 start,
2604 u64 len, get_block_t *get_block);
2606 extern void get_filesystem(struct file_system_type *fs);
2607 extern void put_filesystem(struct file_system_type *fs);
2608 extern struct file_system_type *get_fs_type(const char *name);
2609 extern struct super_block *get_super(struct block_device *);
2610 extern struct super_block *get_super_thawed(struct block_device *);
2611 extern struct super_block *get_active_super(struct block_device *bdev);
2612 extern void drop_super(struct super_block *sb);
2613 extern void iterate_supers(void (*)(struct super_block *, void *), void *);
2614 extern void iterate_supers_type(struct file_system_type *,
2615 void (*)(struct super_block *, void *), void *);
2617 extern int dcache_dir_open(struct inode *, struct file *);
2618 extern int dcache_dir_close(struct inode *, struct file *);
2619 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
2620 extern int dcache_readdir(struct file *, struct dir_context *);
2621 extern int simple_setattr(struct dentry *, struct iattr *);
2622 extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
2623 extern int simple_statfs(struct dentry *, struct kstatfs *);
2624 extern int simple_open(struct inode *inode, struct file *file);
2625 extern int simple_link(struct dentry *, struct inode *, struct dentry *);
2626 extern int simple_unlink(struct inode *, struct dentry *);
2627 extern int simple_rmdir(struct inode *, struct dentry *);
2628 extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
2629 extern int noop_fsync(struct file *, loff_t, loff_t, int);
2630 extern int simple_empty(struct dentry *);
2631 extern int simple_readpage(struct file *file, struct page *page);
2632 extern int simple_write_begin(struct file *file, struct address_space *mapping,
2633 loff_t pos, unsigned len, unsigned flags,
2634 struct page **pagep, void **fsdata);
2635 extern int simple_write_end(struct file *file, struct address_space *mapping,
2636 loff_t pos, unsigned len, unsigned copied,
2637 struct page *page, void *fsdata);
2638 extern int always_delete_dentry(const struct dentry *);
2639 extern struct inode *alloc_anon_inode(struct super_block *);
2640 extern const struct dentry_operations simple_dentry_operations;
2642 extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
2643 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
2644 extern const struct file_operations simple_dir_operations;
2645 extern const struct inode_operations simple_dir_inode_operations;
2646 struct tree_descr { char *name; const struct file_operations *ops; int mode; };
2647 struct dentry *d_alloc_name(struct dentry *, const char *);
2648 extern int simple_fill_super(struct super_block *, unsigned long, struct tree_descr *);
2649 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
2650 extern void simple_release_fs(struct vfsmount **mount, int *count);
2652 extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
2653 loff_t *ppos, const void *from, size_t available);
2654 extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
2655 const void __user *from, size_t count);
2657 extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
2659 extern int generic_check_addressable(unsigned, u64);
2661 #ifdef CONFIG_MIGRATION
2662 extern int buffer_migrate_page(struct address_space *,
2663 struct page *, struct page *,
2666 #define buffer_migrate_page NULL
2669 extern int inode_change_ok(const struct inode *, struct iattr *);
2670 extern int inode_newsize_ok(const struct inode *, loff_t offset);
2671 extern void setattr_copy(struct inode *inode, const struct iattr *attr);
2673 extern int file_update_time(struct file *file);
2675 extern int generic_show_options(struct seq_file *m, struct dentry *root);
2676 extern void save_mount_options(struct super_block *sb, char *options);
2677 extern void replace_mount_options(struct super_block *sb, char *options);
2679 static inline ino_t parent_ino(struct dentry *dentry)
2684 * Don't strictly need d_lock here? If the parent ino could change
2685 * then surely we'd have a deeper race in the caller?
2687 spin_lock(&dentry->d_lock);
2688 res = dentry->d_parent->d_inode->i_ino;
2689 spin_unlock(&dentry->d_lock);
2693 /* Transaction based IO helpers */
2696 * An argresp is stored in an allocated page and holds the
2697 * size of the argument or response, along with its content
2699 struct simple_transaction_argresp {
2704 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
2706 char *simple_transaction_get(struct file *file, const char __user *buf,
2708 ssize_t simple_transaction_read(struct file *file, char __user *buf,
2709 size_t size, loff_t *pos);
2710 int simple_transaction_release(struct inode *inode, struct file *file);
2712 void simple_transaction_set(struct file *file, size_t n);
2715 * simple attribute files
2717 * These attributes behave similar to those in sysfs:
2719 * Writing to an attribute immediately sets a value, an open file can be
2720 * written to multiple times.
2722 * Reading from an attribute creates a buffer from the value that might get
2723 * read with multiple read calls. When the attribute has been read
2724 * completely, no further read calls are possible until the file is opened
2727 * All attributes contain a text representation of a numeric value
2728 * that are accessed with the get() and set() functions.
2730 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
2731 static int __fops ## _open(struct inode *inode, struct file *file) \
2733 __simple_attr_check_format(__fmt, 0ull); \
2734 return simple_attr_open(inode, file, __get, __set, __fmt); \
2736 static const struct file_operations __fops = { \
2737 .owner = THIS_MODULE, \
2738 .open = __fops ## _open, \
2739 .release = simple_attr_release, \
2740 .read = simple_attr_read, \
2741 .write = simple_attr_write, \
2742 .llseek = generic_file_llseek, \
2745 static inline __printf(1, 2)
2746 void __simple_attr_check_format(const char *fmt, ...)
2748 /* don't do anything, just let the compiler check the arguments; */
2751 int simple_attr_open(struct inode *inode, struct file *file,
2752 int (*get)(void *, u64 *), int (*set)(void *, u64),
2754 int simple_attr_release(struct inode *inode, struct file *file);
2755 ssize_t simple_attr_read(struct file *file, char __user *buf,
2756 size_t len, loff_t *ppos);
2757 ssize_t simple_attr_write(struct file *file, const char __user *buf,
2758 size_t len, loff_t *ppos);
2761 int proc_nr_files(struct ctl_table *table, int write,
2762 void __user *buffer, size_t *lenp, loff_t *ppos);
2763 int proc_nr_dentry(struct ctl_table *table, int write,
2764 void __user *buffer, size_t *lenp, loff_t *ppos);
2765 int proc_nr_inodes(struct ctl_table *table, int write,
2766 void __user *buffer, size_t *lenp, loff_t *ppos);
2767 int __init get_filesystem_list(char *buf);
2769 #define __FMODE_EXEC ((__force int) FMODE_EXEC)
2770 #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
2772 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
2773 #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
2774 (flag & __FMODE_NONOTIFY)))
2776 static inline int is_sxid(umode_t mode)
2778 return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
2781 static inline void inode_has_no_xattr(struct inode *inode)
2783 if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & MS_NOSEC))
2784 inode->i_flags |= S_NOSEC;
2787 static inline bool dir_emit(struct dir_context *ctx,
2788 const char *name, int namelen,
2789 u64 ino, unsigned type)
2791 return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0;
2793 static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
2795 return ctx->actor(ctx, ".", 1, ctx->pos,
2796 file->f_path.dentry->d_inode->i_ino, DT_DIR) == 0;
2798 static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
2800 return ctx->actor(ctx, "..", 2, ctx->pos,
2801 parent_ino(file->f_path.dentry), DT_DIR) == 0;
2803 static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
2805 if (ctx->pos == 0) {
2806 if (!dir_emit_dot(file, ctx))
2810 if (ctx->pos == 1) {
2811 if (!dir_emit_dotdot(file, ctx))
2817 static inline bool dir_relax(struct inode *inode)
2819 mutex_unlock(&inode->i_mutex);
2820 mutex_lock(&inode->i_mutex);
2821 return !IS_DEADDIR(inode);
2824 #endif /* _LINUX_FS_H */