2692 lines
89 KiB
C
2692 lines
89 KiB
C
#ifndef _LINUX_FS_H
|
|
#define _LINUX_FS_H
|
|
|
|
|
|
#include <linux/linkage.h>
|
|
#include <linux/wait.h>
|
|
#include <linux/kdev_t.h>
|
|
#include <linux/dcache.h>
|
|
#include <linux/path.h>
|
|
#include <linux/stat.h>
|
|
#include <linux/cache.h>
|
|
#include <linux/list.h>
|
|
#include <linux/radix-tree.h>
|
|
#include <linux/rbtree.h>
|
|
#include <linux/init.h>
|
|
#include <linux/pid.h>
|
|
#include <linux/bug.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/capability.h>
|
|
#include <linux/semaphore.h>
|
|
#include <linux/fiemap.h>
|
|
#include <linux/rculist_bl.h>
|
|
#include <linux/atomic.h>
|
|
#include <linux/shrinker.h>
|
|
#include <linux/migrate_mode.h>
|
|
#include <linux/uidgid.h>
|
|
#include <linux/lockdep.h>
|
|
#include <linux/percpu-rwsem.h>
|
|
#include <linux/blk_types.h>
|
|
|
|
#include <asm/byteorder.h>
|
|
#include <uapi/linux/fs.h>
|
|
|
|
struct export_operations;
|
|
struct hd_geometry;
|
|
struct iovec;
|
|
struct nameidata;
|
|
struct kiocb;
|
|
struct kobject;
|
|
struct pipe_inode_info;
|
|
struct poll_table_struct;
|
|
struct kstatfs;
|
|
struct vm_area_struct;
|
|
struct vfsmount;
|
|
struct cred;
|
|
struct swap_info_struct;
|
|
struct seq_file;
|
|
|
|
extern void __init inode_init(void);
|
|
extern void __init inode_init_early(void);
|
|
extern void __init files_init(unsigned long);
|
|
|
|
extern struct files_stat_struct files_stat;
|
|
extern unsigned long get_max_files(void);
|
|
extern int sysctl_nr_open;
|
|
extern struct inodes_stat_t inodes_stat;
|
|
extern int leases_enable, lease_break_time;
|
|
extern int sysctl_protected_symlinks;
|
|
extern int sysctl_protected_hardlinks;
|
|
|
|
struct buffer_head;
|
|
typedef int (get_block_t)(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh_result, int create);
|
|
typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
|
|
ssize_t bytes, void *private, int ret,
|
|
bool is_async);
|
|
|
|
#define MAY_EXEC 0x00000001
|
|
#define MAY_WRITE 0x00000002
|
|
#define MAY_READ 0x00000004
|
|
#define MAY_APPEND 0x00000008
|
|
#define MAY_ACCESS 0x00000010
|
|
#define MAY_OPEN 0x00000020
|
|
#define MAY_CHDIR 0x00000040
|
|
/* called from RCU mode, don't block */
|
|
#define MAY_NOT_BLOCK 0x00000080
|
|
|
|
/*
|
|
* flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond
|
|
* to O_WRONLY and O_RDWR via the strange trick in __dentry_open()
|
|
*/
|
|
|
|
/* file is open for reading */
|
|
#define FMODE_READ ((__force fmode_t)0x1)
|
|
/* file is open for writing */
|
|
#define FMODE_WRITE ((__force fmode_t)0x2)
|
|
/* file is seekable */
|
|
#define FMODE_LSEEK ((__force fmode_t)0x4)
|
|
/* file can be accessed using pread */
|
|
#define FMODE_PREAD ((__force fmode_t)0x8)
|
|
/* file can be accessed using pwrite */
|
|
#define FMODE_PWRITE ((__force fmode_t)0x10)
|
|
/* File is opened for execution with sys_execve / sys_uselib */
|
|
#define FMODE_EXEC ((__force fmode_t)0x20)
|
|
/* File is opened with O_NDELAY (only set for block devices) */
|
|
#define FMODE_NDELAY ((__force fmode_t)0x40)
|
|
/* File is opened with O_EXCL (only set for block devices) */
|
|
#define FMODE_EXCL ((__force fmode_t)0x80)
|
|
/* File is opened using open(.., 3, ..) and is writeable only for ioctls
|
|
(specialy hack for floppy.c) */
|
|
#define FMODE_WRITE_IOCTL ((__force fmode_t)0x100)
|
|
/* 32bit hashes as llseek() offset (for directories) */
|
|
#define FMODE_32BITHASH ((__force fmode_t)0x200)
|
|
/* 64bit hashes as llseek() offset (for directories) */
|
|
#define FMODE_64BITHASH ((__force fmode_t)0x400)
|
|
|
|
/*
|
|
* Don't update ctime and mtime.
|
|
*
|
|
* Currently a special hack for the XFS open_by_handle ioctl, but we'll
|
|
* hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
|
|
*/
|
|
#define FMODE_NOCMTIME ((__force fmode_t)0x800)
|
|
|
|
/* Expect random access pattern */
|
|
#define FMODE_RANDOM ((__force fmode_t)0x1000)
|
|
|
|
/* File is huge (eg. /dev/kmem): treat loff_t as unsigned */
|
|
#define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
|
|
|
|
/* File is opened with O_PATH; almost nothing can be done with it */
|
|
#define FMODE_PATH ((__force fmode_t)0x4000)
|
|
|
|
/* File was opened by fanotify and shouldn't generate fanotify events */
|
|
#define FMODE_NONOTIFY ((__force fmode_t)0x1000000)
|
|
|
|
/*
|
|
* Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
|
|
* that indicates that they should check the contents of the iovec are
|
|
* valid, but not check the memory that the iovec elements
|
|
* points too.
|
|
*/
|
|
#define CHECK_IOVEC_ONLY -1
|
|
|
|
/*
|
|
* The below are the various read and write types that we support. Some of
|
|
* them include behavioral modifiers that send information down to the
|
|
* block layer and IO scheduler. Terminology:
|
|
*
|
|
* The block layer uses device plugging to defer IO a little bit, in
|
|
* the hope that we will see more IO very shortly. This increases
|
|
* coalescing of adjacent IO and thus reduces the number of IOs we
|
|
* have to send to the device. It also allows for better queuing,
|
|
* if the IO isn't mergeable. If the caller is going to be waiting
|
|
* for the IO, then he must ensure that the device is unplugged so
|
|
* that the IO is dispatched to the driver.
|
|
*
|
|
* All IO is handled async in Linux. This is fine for background
|
|
* writes, but for reads or writes that someone waits for completion
|
|
* on, we want to notify the block layer and IO scheduler so that they
|
|
* know about it. That allows them to make better scheduling
|
|
* decisions. So when the below references 'sync' and 'async', it
|
|
* is referencing this priority hint.
|
|
*
|
|
* With that in mind, the available types are:
|
|
*
|
|
* READ A normal read operation. Device will be plugged.
|
|
* READ_SYNC A synchronous read. Device is not plugged, caller can
|
|
* immediately wait on this read without caring about
|
|
* unplugging.
|
|
* READA Used for read-ahead operations. Lower priority, and the
|
|
* block layer could (in theory) choose to ignore this
|
|
* request if it runs into resource problems.
|
|
* WRITE A normal async write. Device will be plugged.
|
|
* WRITE_SYNC Synchronous write. Identical to WRITE, but passes down
|
|
* the hint that someone will be waiting on this IO
|
|
* shortly. The write equivalent of READ_SYNC.
|
|
* WRITE_ODIRECT Special case write for O_DIRECT only.
|
|
* WRITE_FLUSH Like WRITE_SYNC but with preceding cache flush.
|
|
* WRITE_FUA Like WRITE_SYNC but data is guaranteed to be on
|
|
* non-volatile media on completion.
|
|
* WRITE_FLUSH_FUA Combination of WRITE_FLUSH and FUA. The IO is preceded
|
|
* by a cache flush and data is guaranteed to be on
|
|
* non-volatile media on completion.
|
|
*
|
|
*/
|
|
#define RW_MASK REQ_WRITE
|
|
#define RWA_MASK REQ_RAHEAD
|
|
|
|
#define READ 0
|
|
#define WRITE RW_MASK
|
|
#define READA RWA_MASK
|
|
#define KERNEL_READ (READ|REQ_KERNEL)
|
|
#define KERNEL_WRITE (WRITE|REQ_KERNEL)
|
|
|
|
#define READ_SYNC (READ | REQ_SYNC)
|
|
#define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE)
|
|
#define WRITE_ODIRECT (WRITE | REQ_SYNC)
|
|
#define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH)
|
|
#define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA)
|
|
#define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA)
|
|
|
|
/*
|
|
* Attribute flags. These should be or-ed together to figure out what
|
|
* has been changed!
|
|
*/
|
|
#define ATTR_MODE (1 << 0)
|
|
#define ATTR_UID (1 << 1)
|
|
#define ATTR_GID (1 << 2)
|
|
#define ATTR_SIZE (1 << 3)
|
|
#define ATTR_ATIME (1 << 4)
|
|
#define ATTR_MTIME (1 << 5)
|
|
#define ATTR_CTIME (1 << 6)
|
|
#define ATTR_ATIME_SET (1 << 7)
|
|
#define ATTR_MTIME_SET (1 << 8)
|
|
#define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
|
|
#define ATTR_ATTR_FLAG (1 << 10)
|
|
#define ATTR_KILL_SUID (1 << 11)
|
|
#define ATTR_KILL_SGID (1 << 12)
|
|
#define ATTR_FILE (1 << 13)
|
|
#define ATTR_KILL_PRIV (1 << 14)
|
|
#define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
|
|
#define ATTR_TIMES_SET (1 << 16)
|
|
|
|
/*
|
|
* This is the Inode Attributes structure, used for notify_change(). It
|
|
* uses the above definitions as flags, to know which values have changed.
|
|
* Also, in this manner, a Filesystem can look at only the values it cares
|
|
* about. Basically, these are the attributes that the VFS layer can
|
|
* request to change from the FS layer.
|
|
*
|
|
* Derek Atkins <warlord@MIT.EDU> 94-10-20
|
|
*/
|
|
struct iattr {
|
|
unsigned int ia_valid;
|
|
umode_t ia_mode;
|
|
kuid_t ia_uid;
|
|
kgid_t ia_gid;
|
|
loff_t ia_size;
|
|
struct timespec ia_atime;
|
|
struct timespec ia_mtime;
|
|
struct timespec ia_ctime;
|
|
|
|
/*
|
|
* Not an attribute, but an auxiliary info for filesystems wanting to
|
|
* implement an ftruncate() like method. NOTE: filesystem should
|
|
* check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
|
|
*/
|
|
struct file *ia_file;
|
|
};
|
|
|
|
/*
|
|
* Includes for diskquotas.
|
|
*/
|
|
#include <linux/quota.h>
|
|
|
|
/**
|
|
* enum positive_aop_returns - aop return codes with specific semantics
|
|
*
|
|
* @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
|
|
* completed, that the page is still locked, and
|
|
* should be considered active. The VM uses this hint
|
|
* to return the page to the active list -- it won't
|
|
* be a candidate for writeback again in the near
|
|
* future. Other callers must be careful to unlock
|
|
* the page if they get this return. Returned by
|
|
* writepage();
|
|
*
|
|
* @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
|
|
* unlocked it and the page might have been truncated.
|
|
* The caller should back up to acquiring a new page and
|
|
* trying again. The aop will be taking reasonable
|
|
* precautions not to livelock. If the caller held a page
|
|
* reference, it should drop it before retrying. Returned
|
|
* by readpage().
|
|
*
|
|
* address_space_operation functions return these large constants to indicate
|
|
* special semantics to the caller. These are much larger than the bytes in a
|
|
* page to allow for functions that return the number of bytes operated on in a
|
|
* given page.
|
|
*/
|
|
|
|
enum positive_aop_returns {
|
|
AOP_WRITEPAGE_ACTIVATE = 0x80000,
|
|
AOP_TRUNCATED_PAGE = 0x80001,
|
|
};
|
|
|
|
#define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */
|
|
#define AOP_FLAG_CONT_EXPAND 0x0002 /* called from cont_expand */
|
|
#define AOP_FLAG_NOFS 0x0004 /* used by filesystem to direct
|
|
* helper code (eg buffer layer)
|
|
* to clear GFP_FS from alloc */
|
|
|
|
/*
|
|
* oh the beauties of C type declarations.
|
|
*/
|
|
struct page;
|
|
struct address_space;
|
|
struct writeback_control;
|
|
|
|
struct iov_iter {
|
|
const struct iovec *iov;
|
|
unsigned long nr_segs;
|
|
size_t iov_offset;
|
|
size_t count;
|
|
};
|
|
|
|
size_t iov_iter_copy_from_user_atomic(struct page *page,
|
|
struct iov_iter *i, unsigned long offset, size_t bytes);
|
|
size_t iov_iter_copy_from_user(struct page *page,
|
|
struct iov_iter *i, unsigned long offset, size_t bytes);
|
|
void iov_iter_advance(struct iov_iter *i, size_t bytes);
|
|
int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes);
|
|
size_t iov_iter_single_seg_count(const struct iov_iter *i);
|
|
|
|
static inline void iov_iter_init(struct iov_iter *i,
|
|
const struct iovec *iov, unsigned long nr_segs,
|
|
size_t count, size_t written)
|
|
{
|
|
i->iov = iov;
|
|
i->nr_segs = nr_segs;
|
|
i->iov_offset = 0;
|
|
i->count = count + written;
|
|
|
|
iov_iter_advance(i, written);
|
|
}
|
|
|
|
static inline size_t iov_iter_count(struct iov_iter *i)
|
|
{
|
|
return i->count;
|
|
}
|
|
|
|
/*
|
|
* "descriptor" for what we're up to with a read.
|
|
* This allows us to use the same read code yet
|
|
* have multiple different users of the data that
|
|
* we read from a file.
|
|
*
|
|
* The simplest case just copies the data to user
|
|
* mode.
|
|
*/
|
|
typedef struct {
|
|
size_t written;
|
|
size_t count;
|
|
union {
|
|
char __user *buf;
|
|
void *data;
|
|
} arg;
|
|
int error;
|
|
} read_descriptor_t;
|
|
|
|
typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
|
|
unsigned long, unsigned long);
|
|
|
|
struct address_space_operations {
|
|
int (*writepage)(struct page *page, struct writeback_control *wbc);
|
|
int (*readpage)(struct file *, struct page *);
|
|
|
|
/* Write back some dirty pages from this mapping. */
|
|
int (*writepages)(struct address_space *, struct writeback_control *);
|
|
|
|
/* Set a page dirty. Return true if this dirtied it */
|
|
int (*set_page_dirty)(struct page *page);
|
|
|
|
int (*readpages)(struct file *filp, struct address_space *mapping,
|
|
struct list_head *pages, unsigned nr_pages);
|
|
|
|
int (*write_begin)(struct file *, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata);
|
|
int (*write_end)(struct file *, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata);
|
|
|
|
/* Unfortunately this kludge is needed for FIBMAP. Don't use it */
|
|
sector_t (*bmap)(struct address_space *, sector_t);
|
|
void (*invalidatepage) (struct page *, unsigned long);
|
|
int (*releasepage) (struct page *, gfp_t);
|
|
void (*freepage)(struct page *);
|
|
ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
|
|
loff_t offset, unsigned long nr_segs);
|
|
int (*get_xip_mem)(struct address_space *, pgoff_t, int,
|
|
void **, unsigned long *);
|
|
/*
|
|
* migrate the contents of a page to the specified target. If sync
|
|
* is false, it must not block.
|
|
*/
|
|
int (*migratepage) (struct address_space *,
|
|
struct page *, struct page *, enum migrate_mode);
|
|
int (*launder_page) (struct page *);
|
|
int (*is_partially_uptodate) (struct page *, read_descriptor_t *,
|
|
unsigned long);
|
|
int (*error_remove_page)(struct address_space *, struct page *);
|
|
|
|
/* swapfile support */
|
|
int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
|
|
sector_t *span);
|
|
void (*swap_deactivate)(struct file *file);
|
|
};
|
|
|
|
extern const struct address_space_operations empty_aops;
|
|
|
|
/*
|
|
* pagecache_write_begin/pagecache_write_end must be used by general code
|
|
* to write into the pagecache.
|
|
*/
|
|
int pagecache_write_begin(struct file *, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata);
|
|
|
|
int pagecache_write_end(struct file *, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata);
|
|
|
|
struct backing_dev_info;
|
|
struct address_space {
|
|
struct inode *host; /* owner: inode, block_device */
|
|
struct radix_tree_root page_tree; /* radix tree of all pages */
|
|
spinlock_t tree_lock; /* and lock protecting it */
|
|
unsigned int i_mmap_writable;/* count VM_SHARED mappings */
|
|
struct rb_root i_mmap; /* tree of private and shared mappings */
|
|
struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
|
|
struct mutex i_mmap_mutex; /* protect tree, count, list */
|
|
/* Protected by tree_lock together with the radix tree */
|
|
unsigned long nrpages; /* number of total pages */
|
|
pgoff_t writeback_index;/* writeback starts here */
|
|
const struct address_space_operations *a_ops; /* methods */
|
|
unsigned long flags; /* error bits/gfp mask */
|
|
struct backing_dev_info *backing_dev_info; /* device readahead, etc */
|
|
spinlock_t private_lock; /* for use by the address_space */
|
|
struct list_head private_list; /* ditto */
|
|
void *private_data; /* ditto */
|
|
} __attribute__((aligned(sizeof(long))));
|
|
/*
|
|
* On most architectures that alignment is already the case; but
|
|
* must be enforced here for CRIS, to let the least significant bit
|
|
* of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
|
|
*/
|
|
struct request_queue;
|
|
|
|
struct block_device {
|
|
dev_t bd_dev; /* not a kdev_t - it's a search key */
|
|
int bd_openers;
|
|
struct inode * bd_inode; /* will die */
|
|
struct super_block * bd_super;
|
|
struct mutex bd_mutex; /* open/close mutex */
|
|
struct list_head bd_inodes;
|
|
void * bd_claiming;
|
|
void * bd_holder;
|
|
int bd_holders;
|
|
bool bd_write_holder;
|
|
#ifdef CONFIG_SYSFS
|
|
struct list_head bd_holder_disks;
|
|
#endif
|
|
struct block_device * bd_contains;
|
|
unsigned bd_block_size;
|
|
struct hd_struct * bd_part;
|
|
/* number of times partitions within this device have been opened. */
|
|
unsigned bd_part_count;
|
|
int bd_invalidated;
|
|
struct gendisk * bd_disk;
|
|
struct request_queue * bd_queue;
|
|
struct list_head bd_list;
|
|
/*
|
|
* Private data. You must have bd_claim'ed the block_device
|
|
* to use this. NOTE: bd_claim allows an owner to claim
|
|
* the same device multiple times, the owner must take special
|
|
* care to not mess up bd_private for that case.
|
|
*/
|
|
unsigned long bd_private;
|
|
|
|
/* The counter of freeze processes */
|
|
int bd_fsfreeze_count;
|
|
/* Mutex for freeze */
|
|
struct mutex bd_fsfreeze_mutex;
|
|
};
|
|
|
|
/*
|
|
* Radix-tree tags, for tagging dirty and writeback pages within the pagecache
|
|
* radix trees
|
|
*/
|
|
#define PAGECACHE_TAG_DIRTY 0
|
|
#define PAGECACHE_TAG_WRITEBACK 1
|
|
#define PAGECACHE_TAG_TOWRITE 2
|
|
|
|
int mapping_tagged(struct address_space *mapping, int tag);
|
|
|
|
/*
|
|
* Might pages of this file be mapped into userspace?
|
|
*/
|
|
static inline int mapping_mapped(struct address_space *mapping)
|
|
{
|
|
return !RB_EMPTY_ROOT(&mapping->i_mmap) ||
|
|
!list_empty(&mapping->i_mmap_nonlinear);
|
|
}
|
|
|
|
/*
|
|
* Might pages of this file have been modified in userspace?
|
|
* Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
|
|
* marks vma as VM_SHARED if it is shared, and the file was opened for
|
|
* writing i.e. vma may be mprotected writable even if now readonly.
|
|
*/
|
|
static inline int mapping_writably_mapped(struct address_space *mapping)
|
|
{
|
|
return mapping->i_mmap_writable != 0;
|
|
}
|
|
|
|
/*
|
|
* Use sequence counter to get consistent i_size on 32-bit processors.
|
|
*/
|
|
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
|
|
#include <linux/seqlock.h>
|
|
#define __NEED_I_SIZE_ORDERED
|
|
#define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
|
|
#else
|
|
#define i_size_ordered_init(inode) do { } while (0)
|
|
#endif
|
|
|
|
struct posix_acl;
|
|
#define ACL_NOT_CACHED ((void *)(-1))
|
|
|
|
#define IOP_FASTPERM 0x0001
|
|
#define IOP_LOOKUP 0x0002
|
|
#define IOP_NOFOLLOW 0x0004
|
|
|
|
/*
|
|
* Keep mostly read-only and often accessed (especially for
|
|
* the RCU path lookup and 'stat' data) fields at the beginning
|
|
* of the 'struct inode'
|
|
*/
|
|
struct inode {
|
|
umode_t i_mode;
|
|
unsigned short i_opflags;
|
|
kuid_t i_uid;
|
|
kgid_t i_gid;
|
|
unsigned int i_flags;
|
|
|
|
#ifdef CONFIG_FS_POSIX_ACL
|
|
struct posix_acl *i_acl;
|
|
struct posix_acl *i_default_acl;
|
|
#endif
|
|
|
|
const struct inode_operations *i_op;
|
|
struct super_block *i_sb;
|
|
struct address_space *i_mapping;
|
|
|
|
#ifdef CONFIG_SECURITY
|
|
void *i_security;
|
|
#endif
|
|
|
|
/* Stat data, not accessed from path walking */
|
|
unsigned long i_ino;
|
|
/*
|
|
* Filesystems may only read i_nlink directly. They shall use the
|
|
* following functions for modification:
|
|
*
|
|
* (set|clear|inc|drop)_nlink
|
|
* inode_(inc|dec)_link_count
|
|
*/
|
|
union {
|
|
const unsigned int i_nlink;
|
|
unsigned int __i_nlink;
|
|
};
|
|
dev_t i_rdev;
|
|
loff_t i_size;
|
|
struct timespec i_atime;
|
|
struct timespec i_mtime;
|
|
struct timespec i_ctime;
|
|
spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
|
|
unsigned short i_bytes;
|
|
unsigned int i_blkbits;
|
|
blkcnt_t i_blocks;
|
|
|
|
#ifdef __NEED_I_SIZE_ORDERED
|
|
seqcount_t i_size_seqcount;
|
|
#endif
|
|
|
|
/* Misc */
|
|
unsigned long i_state;
|
|
struct mutex i_mutex;
|
|
|
|
unsigned long dirtied_when; /* jiffies of first dirtying */
|
|
|
|
struct hlist_node i_hash;
|
|
struct list_head i_wb_list; /* backing dev IO list */
|
|
struct list_head i_lru; /* inode LRU list */
|
|
struct list_head i_sb_list;
|
|
union {
|
|
struct hlist_head i_dentry;
|
|
struct rcu_head i_rcu;
|
|
};
|
|
u64 i_version;
|
|
atomic_t i_count;
|
|
atomic_t i_dio_count;
|
|
atomic_t i_writecount;
|
|
const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
|
|
struct file_lock *i_flock;
|
|
struct address_space i_data;
|
|
#ifdef CONFIG_QUOTA
|
|
struct dquot *i_dquot[MAXQUOTAS];
|
|
#endif
|
|
struct list_head i_devices;
|
|
union {
|
|
struct pipe_inode_info *i_pipe;
|
|
struct block_device *i_bdev;
|
|
struct cdev *i_cdev;
|
|
};
|
|
|
|
__u32 i_generation;
|
|
|
|
#ifdef CONFIG_FSNOTIFY
|
|
__u32 i_fsnotify_mask; /* all events this inode cares about */
|
|
struct hlist_head i_fsnotify_marks;
|
|
#endif
|
|
|
|
#ifdef CONFIG_IMA
|
|
atomic_t i_readcount; /* struct files open RO */
|
|
#endif
|
|
void *i_private; /* fs or device private pointer */
|
|
};
|
|
|
|
static inline int inode_unhashed(struct inode *inode)
|
|
{
|
|
return hlist_unhashed(&inode->i_hash);
|
|
}
|
|
|
|
/*
|
|
* inode->i_mutex nesting subclasses for the lock validator:
|
|
*
|
|
* 0: the object of the current VFS operation
|
|
* 1: parent
|
|
* 2: child/target
|
|
* 3: quota file
|
|
*
|
|
* The locking order between these classes is
|
|
* parent -> child -> normal -> xattr -> quota
|
|
*/
|
|
enum inode_i_mutex_lock_class
|
|
{
|
|
I_MUTEX_NORMAL,
|
|
I_MUTEX_PARENT,
|
|
I_MUTEX_CHILD,
|
|
I_MUTEX_XATTR,
|
|
I_MUTEX_QUOTA
|
|
};
|
|
|
|
/*
|
|
* NOTE: in a 32bit arch with a preemptable kernel and
|
|
* an UP compile the i_size_read/write must be atomic
|
|
* with respect to the local cpu (unlike with preempt disabled),
|
|
* but they don't need to be atomic with respect to other cpus like in
|
|
* true SMP (so they need either to either locally disable irq around
|
|
* the read or for example on x86 they can be still implemented as a
|
|
* cmpxchg8b without the need of the lock prefix). For SMP compiles
|
|
* and 64bit archs it makes no difference if preempt is enabled or not.
|
|
*/
|
|
static inline loff_t i_size_read(const struct inode *inode)
|
|
{
|
|
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
|
|
loff_t i_size;
|
|
unsigned int seq;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&inode->i_size_seqcount);
|
|
i_size = inode->i_size;
|
|
} while (read_seqcount_retry(&inode->i_size_seqcount, seq));
|
|
return i_size;
|
|
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
|
|
loff_t i_size;
|
|
|
|
preempt_disable();
|
|
i_size = inode->i_size;
|
|
preempt_enable();
|
|
return i_size;
|
|
#else
|
|
return inode->i_size;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* NOTE: unlike i_size_read(), i_size_write() does need locking around it
|
|
* (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
|
|
* can be lost, resulting in subsequent i_size_read() calls spinning forever.
|
|
*/
|
|
static inline void i_size_write(struct inode *inode, loff_t i_size)
|
|
{
|
|
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
|
|
preempt_disable();
|
|
write_seqcount_begin(&inode->i_size_seqcount);
|
|
inode->i_size = i_size;
|
|
write_seqcount_end(&inode->i_size_seqcount);
|
|
preempt_enable();
|
|
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
|
|
preempt_disable();
|
|
inode->i_size = i_size;
|
|
preempt_enable();
|
|
#else
|
|
inode->i_size = i_size;
|
|
#endif
|
|
}
|
|
|
|
/* Helper functions so that in most cases filesystems will
|
|
* not need to deal directly with kuid_t and kgid_t and can
|
|
* instead deal with the raw numeric values that are stored
|
|
* in the filesystem.
|
|
*/
|
|
static inline uid_t i_uid_read(const struct inode *inode)
|
|
{
|
|
return from_kuid(&init_user_ns, inode->i_uid);
|
|
}
|
|
|
|
static inline gid_t i_gid_read(const struct inode *inode)
|
|
{
|
|
return from_kgid(&init_user_ns, inode->i_gid);
|
|
}
|
|
|
|
static inline void i_uid_write(struct inode *inode, uid_t uid)
|
|
{
|
|
inode->i_uid = make_kuid(&init_user_ns, uid);
|
|
}
|
|
|
|
static inline void i_gid_write(struct inode *inode, gid_t gid)
|
|
{
|
|
inode->i_gid = make_kgid(&init_user_ns, gid);
|
|
}
|
|
|
|
static inline unsigned iminor(const struct inode *inode)
|
|
{
|
|
return MINOR(inode->i_rdev);
|
|
}
|
|
|
|
static inline unsigned imajor(const struct inode *inode)
|
|
{
|
|
return MAJOR(inode->i_rdev);
|
|
}
|
|
|
|
extern struct block_device *I_BDEV(struct inode *inode);
|
|
|
|
struct fown_struct {
|
|
rwlock_t lock; /* protects pid, uid, euid fields */
|
|
struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
|
|
enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
|
|
kuid_t uid, euid; /* uid/euid of process setting the owner */
|
|
int signum; /* posix.1b rt signal to be delivered on IO */
|
|
};
|
|
|
|
/*
|
|
* Track a single file's readahead state
|
|
*/
|
|
struct file_ra_state {
|
|
pgoff_t start; /* where readahead started */
|
|
unsigned int size; /* # of readahead pages */
|
|
unsigned int async_size; /* do asynchronous readahead when
|
|
there are only # of pages ahead */
|
|
|
|
unsigned int ra_pages; /* Maximum readahead window */
|
|
unsigned int mmap_miss; /* Cache miss stat for mmap accesses */
|
|
loff_t prev_pos; /* Cache last read() position */
|
|
};
|
|
|
|
/*
|
|
* Check if @index falls in the readahead windows.
|
|
*/
|
|
static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
|
|
{
|
|
return (index >= ra->start &&
|
|
index < ra->start + ra->size);
|
|
}
|
|
|
|
#define FILE_MNT_WRITE_TAKEN 1
|
|
#define FILE_MNT_WRITE_RELEASED 2
|
|
|
|
struct file {
|
|
/*
|
|
* fu_list becomes invalid after file_free is called and queued via
|
|
* fu_rcuhead for RCU freeing
|
|
*/
|
|
union {
|
|
struct list_head fu_list;
|
|
struct rcu_head fu_rcuhead;
|
|
} f_u;
|
|
struct path f_path;
|
|
#define f_dentry f_path.dentry
|
|
struct inode *f_inode; /* cached value */
|
|
const struct file_operations *f_op;
|
|
|
|
/*
|
|
* Protects f_ep_links, f_flags, f_pos vs i_size in lseek SEEK_CUR.
|
|
* Must not be taken from IRQ context.
|
|
*/
|
|
spinlock_t f_lock;
|
|
#ifdef CONFIG_SMP
|
|
int f_sb_list_cpu;
|
|
#endif
|
|
atomic_long_t f_count;
|
|
unsigned int f_flags;
|
|
fmode_t f_mode;
|
|
loff_t f_pos;
|
|
struct fown_struct f_owner;
|
|
const struct cred *f_cred;
|
|
struct file_ra_state f_ra;
|
|
|
|
u64 f_version;
|
|
#ifdef CONFIG_SECURITY
|
|
void *f_security;
|
|
#endif
|
|
/* needed for tty driver, and maybe others */
|
|
void *private_data;
|
|
|
|
#ifdef CONFIG_EPOLL
|
|
/* Used by fs/eventpoll.c to link all the hooks to this file */
|
|
struct list_head f_ep_links;
|
|
struct list_head f_tfile_llink;
|
|
#endif /* #ifdef CONFIG_EPOLL */
|
|
struct address_space *f_mapping;
|
|
#ifdef CONFIG_DEBUG_WRITECOUNT
|
|
unsigned long f_mnt_write_state;
|
|
#endif
|
|
};
|
|
|
|
struct file_handle {
|
|
__u32 handle_bytes;
|
|
int handle_type;
|
|
/* file identifier */
|
|
unsigned char f_handle[0];
|
|
};
|
|
|
|
static inline struct file *get_file(struct file *f)
|
|
{
|
|
atomic_long_inc(&f->f_count);
|
|
return f;
|
|
}
|
|
#define fput_atomic(x) atomic_long_add_unless(&(x)->f_count, -1, 1)
|
|
#define file_count(x) atomic_long_read(&(x)->f_count)
|
|
|
|
#ifdef CONFIG_DEBUG_WRITECOUNT
|
|
static inline void file_take_write(struct file *f)
|
|
{
|
|
WARN_ON(f->f_mnt_write_state != 0);
|
|
f->f_mnt_write_state = FILE_MNT_WRITE_TAKEN;
|
|
}
|
|
static inline void file_release_write(struct file *f)
|
|
{
|
|
f->f_mnt_write_state |= FILE_MNT_WRITE_RELEASED;
|
|
}
|
|
static inline void file_reset_write(struct file *f)
|
|
{
|
|
f->f_mnt_write_state = 0;
|
|
}
|
|
static inline void file_check_state(struct file *f)
|
|
{
|
|
/*
|
|
* At this point, either both or neither of these bits
|
|
* should be set.
|
|
*/
|
|
WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN);
|
|
WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_RELEASED);
|
|
}
|
|
static inline int file_check_writeable(struct file *f)
|
|
{
|
|
if (f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN)
|
|
return 0;
|
|
printk(KERN_WARNING "writeable file with no "
|
|
"mnt_want_write()\n");
|
|
WARN_ON(1);
|
|
return -EINVAL;
|
|
}
|
|
#else /* !CONFIG_DEBUG_WRITECOUNT */
|
|
static inline void file_take_write(struct file *filp) {}
|
|
static inline void file_release_write(struct file *filp) {}
|
|
static inline void file_reset_write(struct file *filp) {}
|
|
static inline void file_check_state(struct file *filp) {}
|
|
static inline int file_check_writeable(struct file *filp)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_DEBUG_WRITECOUNT */
|
|
|
|
#define MAX_NON_LFS ((1UL<<31) - 1)
|
|
|
|
/* Page cache limit. The filesystems should put that into their s_maxbytes
|
|
limits, otherwise bad things can happen in VM. */
|
|
#if BITS_PER_LONG==32
|
|
#define MAX_LFS_FILESIZE (((loff_t)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
|
|
#elif BITS_PER_LONG==64
|
|
#define MAX_LFS_FILESIZE ((loff_t)0x7fffffffffffffffLL)
|
|
#endif
|
|
|
|
#define FL_POSIX 1
|
|
#define FL_FLOCK 2
|
|
#define FL_ACCESS 8 /* not trying to lock, just looking */
|
|
#define FL_EXISTS 16 /* when unlocking, test for existence */
|
|
#define FL_LEASE 32 /* lease held on this file */
|
|
#define FL_CLOSE 64 /* unlock on close */
|
|
#define FL_SLEEP 128 /* A blocking lock */
|
|
#define FL_DOWNGRADE_PENDING 256 /* Lease is being downgraded */
|
|
#define FL_UNLOCK_PENDING 512 /* Lease is being broken */
|
|
|
|
/*
|
|
* Special return value from posix_lock_file() and vfs_lock_file() for
|
|
* asynchronous locking.
|
|
*/
|
|
#define FILE_LOCK_DEFERRED 1
|
|
|
|
/*
|
|
* The POSIX file lock owner is determined by
|
|
* the "struct files_struct" in the thread group
|
|
* (or NULL for no owner - BSD locks).
|
|
*
|
|
* Lockd stuffs a "host" pointer into this.
|
|
*/
|
|
typedef struct files_struct *fl_owner_t;
|
|
|
|
struct file_lock_operations {
|
|
void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
|
|
void (*fl_release_private)(struct file_lock *);
|
|
};
|
|
|
|
struct lock_manager_operations {
|
|
int (*lm_compare_owner)(struct file_lock *, struct file_lock *);
|
|
void (*lm_notify)(struct file_lock *); /* unblock callback */
|
|
int (*lm_grant)(struct file_lock *, struct file_lock *, int);
|
|
void (*lm_break)(struct file_lock *);
|
|
int (*lm_change)(struct file_lock **, int);
|
|
};
|
|
|
|
struct lock_manager {
|
|
struct list_head list;
|
|
};
|
|
|
|
struct net;
|
|
void locks_start_grace(struct net *, struct lock_manager *);
|
|
void locks_end_grace(struct lock_manager *);
|
|
int locks_in_grace(struct net *);
|
|
|
|
/* that will die - we need it for nfs_lock_info */
|
|
#include <linux/nfs_fs_i.h>
|
|
|
|
struct file_lock {
|
|
struct file_lock *fl_next; /* singly linked list for this inode */
|
|
struct list_head fl_link; /* doubly linked list of all locks */
|
|
struct list_head fl_block; /* circular list of blocked processes */
|
|
fl_owner_t fl_owner;
|
|
unsigned int fl_flags;
|
|
unsigned char fl_type;
|
|
unsigned int fl_pid;
|
|
struct pid *fl_nspid;
|
|
wait_queue_head_t fl_wait;
|
|
struct file *fl_file;
|
|
loff_t fl_start;
|
|
loff_t fl_end;
|
|
|
|
struct fasync_struct * fl_fasync; /* for lease break notifications */
|
|
/* for lease breaks: */
|
|
unsigned long fl_break_time;
|
|
unsigned long fl_downgrade_time;
|
|
|
|
const struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
|
|
const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
|
|
union {
|
|
struct nfs_lock_info nfs_fl;
|
|
struct nfs4_lock_info nfs4_fl;
|
|
struct {
|
|
struct list_head link; /* link in AFS vnode's pending_locks list */
|
|
int state; /* state of grant or error if -ve */
|
|
} afs;
|
|
} fl_u;
|
|
};
|
|
|
|
/* The following constant reflects the upper bound of the file/locking space */
|
|
#ifndef OFFSET_MAX
|
|
#define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
|
|
#define OFFSET_MAX INT_LIMIT(loff_t)
|
|
#define OFFT_OFFSET_MAX INT_LIMIT(off_t)
|
|
#endif
|
|
|
|
#include <linux/fcntl.h>
|
|
|
|
extern void send_sigio(struct fown_struct *fown, int fd, int band);
|
|
|
|
#ifdef CONFIG_FILE_LOCKING
|
|
extern int fcntl_getlk(struct file *, struct flock __user *);
|
|
extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
|
|
struct flock __user *);
|
|
|
|
#if BITS_PER_LONG == 32
|
|
extern int fcntl_getlk64(struct file *, struct flock64 __user *);
|
|
extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
|
|
struct flock64 __user *);
|
|
#endif
|
|
|
|
extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
|
|
extern int fcntl_getlease(struct file *filp);
|
|
|
|
/* fs/locks.c */
|
|
void locks_free_lock(struct file_lock *fl);
|
|
extern void locks_init_lock(struct file_lock *);
|
|
extern struct file_lock * locks_alloc_lock(void);
|
|
extern void locks_copy_lock(struct file_lock *, struct file_lock *);
|
|
extern void __locks_copy_lock(struct file_lock *, const struct file_lock *);
|
|
extern void locks_remove_posix(struct file *, fl_owner_t);
|
|
extern void locks_remove_flock(struct file *);
|
|
extern void locks_release_private(struct file_lock *);
|
|
extern void posix_test_lock(struct file *, struct file_lock *);
|
|
extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
|
|
extern int posix_lock_file_wait(struct file *, struct file_lock *);
|
|
extern int posix_unblock_lock(struct file *, struct file_lock *);
|
|
extern int vfs_test_lock(struct file *, struct file_lock *);
|
|
extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
|
|
extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
|
|
extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
|
|
extern int __break_lease(struct inode *inode, unsigned int flags);
|
|
extern void lease_get_mtime(struct inode *, struct timespec *time);
|
|
extern int generic_setlease(struct file *, long, struct file_lock **);
|
|
extern int vfs_setlease(struct file *, long, struct file_lock **);
|
|
extern int lease_modify(struct file_lock **, int);
|
|
extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
|
|
extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
|
|
extern void locks_delete_block(struct file_lock *waiter);
|
|
extern void lock_flocks(void);
|
|
extern void unlock_flocks(void);
|
|
#else /* !CONFIG_FILE_LOCKING */
|
|
static inline int fcntl_getlk(struct file *file, struct flock __user *user)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int fcntl_setlk(unsigned int fd, struct file *file,
|
|
unsigned int cmd, struct flock __user *user)
|
|
{
|
|
return -EACCES;
|
|
}
|
|
|
|
#if BITS_PER_LONG == 32
|
|
static inline int fcntl_getlk64(struct file *file, struct flock64 __user *user)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int fcntl_setlk64(unsigned int fd, struct file *file,
|
|
unsigned int cmd, struct flock64 __user *user)
|
|
{
|
|
return -EACCES;
|
|
}
|
|
#endif
|
|
static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int fcntl_getlease(struct file *filp)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void locks_init_lock(struct file_lock *fl)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static inline void __locks_copy_lock(struct file_lock *new, struct file_lock *fl)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static inline void locks_remove_flock(struct file *filp)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static inline void posix_test_lock(struct file *filp, struct file_lock *fl)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
|
|
struct file_lock *conflock)
|
|
{
|
|
return -ENOLCK;
|
|
}
|
|
|
|
static inline int posix_lock_file_wait(struct file *filp, struct file_lock *fl)
|
|
{
|
|
return -ENOLCK;
|
|
}
|
|
|
|
static inline int posix_unblock_lock(struct file *filp,
|
|
struct file_lock *waiter)
|
|
{
|
|
return -ENOENT;
|
|
}
|
|
|
|
static inline int vfs_test_lock(struct file *filp, struct file_lock *fl)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int vfs_lock_file(struct file *filp, unsigned int cmd,
|
|
struct file_lock *fl, struct file_lock *conf)
|
|
{
|
|
return -ENOLCK;
|
|
}
|
|
|
|
static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int flock_lock_file_wait(struct file *filp,
|
|
struct file_lock *request)
|
|
{
|
|
return -ENOLCK;
|
|
}
|
|
|
|
static inline int __break_lease(struct inode *inode, unsigned int mode)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void lease_get_mtime(struct inode *inode, struct timespec *time)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static inline int generic_setlease(struct file *filp, long arg,
|
|
struct file_lock **flp)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int vfs_setlease(struct file *filp, long arg,
|
|
struct file_lock **lease)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int lease_modify(struct file_lock **before, int arg)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int lock_may_read(struct inode *inode, loff_t start,
|
|
unsigned long len)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static inline int lock_may_write(struct inode *inode, loff_t start,
|
|
unsigned long len)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static inline void locks_delete_block(struct file_lock *waiter)
|
|
{
|
|
}
|
|
|
|
static inline void lock_flocks(void)
|
|
{
|
|
}
|
|
|
|
static inline void unlock_flocks(void)
|
|
{
|
|
}
|
|
|
|
#endif /* !CONFIG_FILE_LOCKING */
|
|
|
|
|
|
struct fasync_struct {
|
|
spinlock_t fa_lock;
|
|
int magic;
|
|
int fa_fd;
|
|
struct fasync_struct *fa_next; /* singly linked list */
|
|
struct file *fa_file;
|
|
struct rcu_head fa_rcu;
|
|
};
|
|
|
|
#define FASYNC_MAGIC 0x4601
|
|
|
|
/* SMP safe fasync helpers: */
|
|
extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
|
|
extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
|
|
extern int fasync_remove_entry(struct file *, struct fasync_struct **);
|
|
extern struct fasync_struct *fasync_alloc(void);
|
|
extern void fasync_free(struct fasync_struct *);
|
|
|
|
/* can be called from interrupts */
|
|
extern void kill_fasync(struct fasync_struct **, int, int);
|
|
|
|
extern int __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
|
|
extern int f_setown(struct file *filp, unsigned long arg, int force);
|
|
extern void f_delown(struct file *filp);
|
|
extern pid_t f_getown(struct file *filp);
|
|
extern int send_sigurg(struct fown_struct *fown);
|
|
|
|
struct mm_struct;
|
|
|
|
/*
|
|
* Umount options
|
|
*/
|
|
|
|
#define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
|
|
#define MNT_DETACH 0x00000002 /* Just detach from the tree */
|
|
#define MNT_EXPIRE 0x00000004 /* Mark for expiry */
|
|
#define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
|
|
#define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
|
|
|
|
extern struct list_head super_blocks;
|
|
extern spinlock_t sb_lock;
|
|
|
|
/* Possible states of 'frozen' field */
|
|
enum {
|
|
SB_UNFROZEN = 0, /* FS is unfrozen */
|
|
SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */
|
|
SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */
|
|
SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop
|
|
* internal threads if needed) */
|
|
SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */
|
|
};
|
|
|
|
#define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
|
|
|
|
struct sb_writers {
|
|
/* Counters for counting writers at each level */
|
|
struct percpu_counter counter[SB_FREEZE_LEVELS];
|
|
wait_queue_head_t wait; /* queue for waiting for
|
|
writers / faults to finish */
|
|
int frozen; /* Is sb frozen? */
|
|
wait_queue_head_t wait_unfrozen; /* queue for waiting for
|
|
sb to be thawed */
|
|
#ifdef CONFIG_DEBUG_LOCK_ALLOC
|
|
struct lockdep_map lock_map[SB_FREEZE_LEVELS];
|
|
#endif
|
|
};
|
|
|
|
struct super_block {
|
|
struct list_head s_list; /* Keep this first */
|
|
dev_t s_dev; /* search index; _not_ kdev_t */
|
|
unsigned char s_blocksize_bits;
|
|
unsigned long s_blocksize;
|
|
loff_t s_maxbytes; /* Max file size */
|
|
struct file_system_type *s_type;
|
|
const struct super_operations *s_op;
|
|
const struct dquot_operations *dq_op;
|
|
const struct quotactl_ops *s_qcop;
|
|
const struct export_operations *s_export_op;
|
|
unsigned long s_flags;
|
|
unsigned long s_magic;
|
|
struct dentry *s_root;
|
|
struct rw_semaphore s_umount;
|
|
int s_count;
|
|
atomic_t s_active;
|
|
#ifdef CONFIG_SECURITY
|
|
void *s_security;
|
|
#endif
|
|
const struct xattr_handler **s_xattr;
|
|
|
|
struct list_head s_inodes; /* all inodes */
|
|
struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */
|
|
#ifdef CONFIG_SMP
|
|
struct list_head __percpu *s_files;
|
|
#else
|
|
struct list_head s_files;
|
|
#endif
|
|
struct list_head s_mounts; /* list of mounts; _not_ for fs use */
|
|
/* s_dentry_lru, s_nr_dentry_unused protected by dcache.c lru locks */
|
|
struct list_head s_dentry_lru; /* unused dentry lru */
|
|
int s_nr_dentry_unused; /* # of dentry on lru */
|
|
|
|
/* s_inode_lru_lock protects s_inode_lru and s_nr_inodes_unused */
|
|
spinlock_t s_inode_lru_lock ____cacheline_aligned_in_smp;
|
|
struct list_head s_inode_lru; /* unused inode lru */
|
|
int s_nr_inodes_unused; /* # of inodes on lru */
|
|
|
|
struct block_device *s_bdev;
|
|
struct backing_dev_info *s_bdi;
|
|
struct mtd_info *s_mtd;
|
|
struct hlist_node s_instances;
|
|
struct quota_info s_dquot; /* Diskquota specific options */
|
|
|
|
struct sb_writers s_writers;
|
|
|
|
char s_id[32]; /* Informational name */
|
|
u8 s_uuid[16]; /* UUID */
|
|
|
|
void *s_fs_info; /* Filesystem private info */
|
|
unsigned int s_max_links;
|
|
fmode_t s_mode;
|
|
|
|
/* Granularity of c/m/atime in ns.
|
|
Cannot be worse than a second */
|
|
u32 s_time_gran;
|
|
|
|
/*
|
|
* The next field is for VFS *only*. No filesystems have any business
|
|
* even looking at it. You had been warned.
|
|
*/
|
|
struct mutex s_vfs_rename_mutex; /* Kludge */
|
|
|
|
/*
|
|
* Filesystem subtype. If non-empty the filesystem type field
|
|
* in /proc/mounts will be "type.subtype"
|
|
*/
|
|
char *s_subtype;
|
|
|
|
/*
|
|
* Saved mount options for lazy filesystems using
|
|
* generic_show_options()
|
|
*/
|
|
char __rcu *s_options;
|
|
const struct dentry_operations *s_d_op; /* default d_op for dentries */
|
|
|
|
/*
|
|
* Saved pool identifier for cleancache (-1 means none)
|
|
*/
|
|
int cleancache_poolid;
|
|
|
|
struct shrinker s_shrink; /* per-sb shrinker handle */
|
|
|
|
/* Number of inodes with nlink == 0 but still referenced */
|
|
atomic_long_t s_remove_count;
|
|
|
|
/* Being remounted read-only */
|
|
int s_readonly_remount;
|
|
};
|
|
|
|
/* superblock cache pruning functions */
|
|
extern void prune_icache_sb(struct super_block *sb, int nr_to_scan);
|
|
extern void prune_dcache_sb(struct super_block *sb, int nr_to_scan);
|
|
|
|
extern struct timespec current_fs_time(struct super_block *sb);
|
|
|
|
/*
|
|
* Snapshotting support.
|
|
*/
|
|
|
|
void __sb_end_write(struct super_block *sb, int level);
|
|
int __sb_start_write(struct super_block *sb, int level, bool wait);
|
|
|
|
/**
|
|
* sb_end_write - drop write access to a superblock
|
|
* @sb: the super we wrote to
|
|
*
|
|
* Decrement number of writers to the filesystem. Wake up possible waiters
|
|
* wanting to freeze the filesystem.
|
|
*/
|
|
static inline void sb_end_write(struct super_block *sb)
|
|
{
|
|
__sb_end_write(sb, SB_FREEZE_WRITE);
|
|
}
|
|
|
|
/**
|
|
* sb_end_pagefault - drop write access to a superblock from a page fault
|
|
* @sb: the super we wrote to
|
|
*
|
|
* Decrement number of processes handling write page fault to the filesystem.
|
|
* Wake up possible waiters wanting to freeze the filesystem.
|
|
*/
|
|
static inline void sb_end_pagefault(struct super_block *sb)
|
|
{
|
|
__sb_end_write(sb, SB_FREEZE_PAGEFAULT);
|
|
}
|
|
|
|
/**
|
|
* sb_end_intwrite - drop write access to a superblock for internal fs purposes
|
|
* @sb: the super we wrote to
|
|
*
|
|
* Decrement fs-internal number of writers to the filesystem. Wake up possible
|
|
* waiters wanting to freeze the filesystem.
|
|
*/
|
|
static inline void sb_end_intwrite(struct super_block *sb)
|
|
{
|
|
__sb_end_write(sb, SB_FREEZE_FS);
|
|
}
|
|
|
|
/**
|
|
* sb_start_write - get write access to a superblock
|
|
* @sb: the super we write to
|
|
*
|
|
* When a process wants to write data or metadata to a file system (i.e. dirty
|
|
* a page or an inode), it should embed the operation in a sb_start_write() -
|
|
* sb_end_write() pair to get exclusion against file system freezing. This
|
|
* function increments number of writers preventing freezing. If the file
|
|
* system is already frozen, the function waits until the file system is
|
|
* thawed.
|
|
*
|
|
* Since freeze protection behaves as a lock, users have to preserve
|
|
* ordering of freeze protection and other filesystem locks. Generally,
|
|
* freeze protection should be the outermost lock. In particular, we have:
|
|
*
|
|
* sb_start_write
|
|
* -> i_mutex (write path, truncate, directory ops, ...)
|
|
* -> s_umount (freeze_super, thaw_super)
|
|
*/
|
|
static inline void sb_start_write(struct super_block *sb)
|
|
{
|
|
__sb_start_write(sb, SB_FREEZE_WRITE, true);
|
|
}
|
|
|
|
static inline int sb_start_write_trylock(struct super_block *sb)
|
|
{
|
|
return __sb_start_write(sb, SB_FREEZE_WRITE, false);
|
|
}
|
|
|
|
/**
|
|
* sb_start_pagefault - get write access to a superblock from a page fault
|
|
* @sb: the super we write to
|
|
*
|
|
* When a process starts handling write page fault, it should embed the
|
|
* operation into sb_start_pagefault() - sb_end_pagefault() pair to get
|
|
* exclusion against file system freezing. This is needed since the page fault
|
|
* is going to dirty a page. This function increments number of running page
|
|
* faults preventing freezing. If the file system is already frozen, the
|
|
* function waits until the file system is thawed.
|
|
*
|
|
* Since page fault freeze protection behaves as a lock, users have to preserve
|
|
* ordering of freeze protection and other filesystem locks. It is advised to
|
|
* put sb_start_pagefault() close to mmap_sem in lock ordering. Page fault
|
|
* handling code implies lock dependency:
|
|
*
|
|
* mmap_sem
|
|
* -> sb_start_pagefault
|
|
*/
|
|
static inline void sb_start_pagefault(struct super_block *sb)
|
|
{
|
|
__sb_start_write(sb, SB_FREEZE_PAGEFAULT, true);
|
|
}
|
|
|
|
/*
|
|
* sb_start_intwrite - get write access to a superblock for internal fs purposes
|
|
* @sb: the super we write to
|
|
*
|
|
* This is the third level of protection against filesystem freezing. It is
|
|
* free for use by a filesystem. The only requirement is that it must rank
|
|
* below sb_start_pagefault.
|
|
*
|
|
* For example filesystem can call sb_start_intwrite() when starting a
|
|
* transaction which somewhat eases handling of freezing for internal sources
|
|
* of filesystem changes (internal fs threads, discarding preallocation on file
|
|
* close, etc.).
|
|
*/
|
|
static inline void sb_start_intwrite(struct super_block *sb)
|
|
{
|
|
__sb_start_write(sb, SB_FREEZE_FS, true);
|
|
}
|
|
|
|
|
|
extern bool inode_owner_or_capable(const struct inode *inode);
|
|
|
|
/*
|
|
* VFS helper functions..
|
|
*/
|
|
extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
|
|
extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
|
|
extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
|
|
extern int vfs_symlink(struct inode *, struct dentry *, const char *);
|
|
extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
|
|
extern int vfs_rmdir(struct inode *, struct dentry *);
|
|
extern int vfs_unlink(struct inode *, struct dentry *);
|
|
extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
|
|
|
|
/*
|
|
* VFS dentry helper functions.
|
|
*/
|
|
extern void dentry_unhash(struct dentry *dentry);
|
|
|
|
/*
|
|
* VFS file helper functions.
|
|
*/
|
|
extern void inode_init_owner(struct inode *inode, const struct inode *dir,
|
|
umode_t mode);
|
|
/*
|
|
* VFS FS_IOC_FIEMAP helper definitions.
|
|
*/
|
|
struct fiemap_extent_info {
|
|
unsigned int fi_flags; /* Flags as passed from user */
|
|
unsigned int fi_extents_mapped; /* Number of mapped extents */
|
|
unsigned int fi_extents_max; /* Size of fiemap_extent array */
|
|
struct fiemap_extent __user *fi_extents_start; /* Start of
|
|
fiemap_extent array */
|
|
};
|
|
int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
|
|
u64 phys, u64 len, u32 flags);
|
|
int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
|
|
|
|
/*
|
|
* File types
|
|
*
|
|
* NOTE! These match bits 12..15 of stat.st_mode
|
|
* (ie "(i_mode >> 12) & 15").
|
|
*/
|
|
#define DT_UNKNOWN 0
|
|
#define DT_FIFO 1
|
|
#define DT_CHR 2
|
|
#define DT_DIR 4
|
|
#define DT_BLK 6
|
|
#define DT_REG 8
|
|
#define DT_LNK 10
|
|
#define DT_SOCK 12
|
|
#define DT_WHT 14
|
|
|
|
/*
|
|
* This is the "filldir" function type, used by readdir() to let
|
|
* the kernel specify what kind of dirent layout it wants to have.
|
|
* This allows the kernel to read directories into kernel space or
|
|
* to have different dirent layouts depending on the binary type.
|
|
*/
|
|
typedef int (*filldir_t)(void *, const char *, int, loff_t, u64, unsigned);
|
|
struct block_device_operations;
|
|
|
|
/* These macros are for out of kernel modules to test that
|
|
* the kernel supports the unlocked_ioctl and compat_ioctl
|
|
* fields in struct file_operations. */
|
|
#define HAVE_COMPAT_IOCTL 1
|
|
#define HAVE_UNLOCKED_IOCTL 1
|
|
|
|
struct file_operations {
|
|
struct module *owner;
|
|
loff_t (*llseek) (struct file *, loff_t, int);
|
|
ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
|
|
ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
|
|
ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
|
|
ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
|
|
int (*readdir) (struct file *, void *, filldir_t);
|
|
unsigned int (*poll) (struct file *, struct poll_table_struct *);
|
|
long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
|
|
long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
|
|
int (*mmap) (struct file *, struct vm_area_struct *);
|
|
int (*open) (struct inode *, struct file *);
|
|
int (*flush) (struct file *, fl_owner_t id);
|
|
int (*release) (struct inode *, struct file *);
|
|
int (*fsync) (struct file *, loff_t, loff_t, int datasync);
|
|
int (*aio_fsync) (struct kiocb *, int datasync);
|
|
int (*fasync) (int, struct file *, int);
|
|
int (*lock) (struct file *, int, struct file_lock *);
|
|
ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
|
|
unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
|
|
int (*check_flags)(int);
|
|
int (*flock) (struct file *, int, struct file_lock *);
|
|
ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
|
|
ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
|
|
int (*setlease)(struct file *, long, struct file_lock **);
|
|
long (*fallocate)(struct file *file, int mode, loff_t offset,
|
|
loff_t len);
|
|
int (*show_fdinfo)(struct seq_file *m, struct file *f);
|
|
};
|
|
|
|
struct inode_operations {
|
|
struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
|
|
void * (*follow_link) (struct dentry *, struct nameidata *);
|
|
int (*permission) (struct inode *, int);
|
|
struct posix_acl * (*get_acl)(struct inode *, int);
|
|
|
|
int (*readlink) (struct dentry *, char __user *,int);
|
|
void (*put_link) (struct dentry *, struct nameidata *, void *);
|
|
|
|
int (*create) (struct inode *,struct dentry *, umode_t, bool);
|
|
int (*link) (struct dentry *,struct inode *,struct dentry *);
|
|
int (*unlink) (struct inode *,struct dentry *);
|
|
int (*symlink) (struct inode *,struct dentry *,const char *);
|
|
int (*mkdir) (struct inode *,struct dentry *,umode_t);
|
|
int (*rmdir) (struct inode *,struct dentry *);
|
|
int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
|
|
int (*rename) (struct inode *, struct dentry *,
|
|
struct inode *, struct dentry *);
|
|
int (*setattr) (struct dentry *, struct iattr *);
|
|
int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
|
|
int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
|
|
ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
|
|
ssize_t (*listxattr) (struct dentry *, char *, size_t);
|
|
int (*removexattr) (struct dentry *, const char *);
|
|
int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
|
|
u64 len);
|
|
int (*update_time)(struct inode *, struct timespec *, int);
|
|
int (*atomic_open)(struct inode *, struct dentry *,
|
|
struct file *, unsigned open_flag,
|
|
umode_t create_mode, int *opened);
|
|
} ____cacheline_aligned;
|
|
|
|
ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
|
|
unsigned long nr_segs, unsigned long fast_segs,
|
|
struct iovec *fast_pointer,
|
|
struct iovec **ret_pointer);
|
|
|
|
extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
|
|
extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
|
|
extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
|
|
unsigned long, loff_t *);
|
|
extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
|
|
unsigned long, loff_t *);
|
|
|
|
struct super_operations {
|
|
struct inode *(*alloc_inode)(struct super_block *sb);
|
|
void (*destroy_inode)(struct inode *);
|
|
|
|
void (*dirty_inode) (struct inode *, int flags);
|
|
int (*write_inode) (struct inode *, struct writeback_control *wbc);
|
|
int (*drop_inode) (struct inode *);
|
|
void (*evict_inode) (struct inode *);
|
|
void (*put_super) (struct super_block *);
|
|
int (*sync_fs)(struct super_block *sb, int wait);
|
|
int (*freeze_fs) (struct super_block *);
|
|
int (*unfreeze_fs) (struct super_block *);
|
|
int (*statfs) (struct dentry *, struct kstatfs *);
|
|
int (*remount_fs) (struct super_block *, int *, char *);
|
|
void (*umount_begin) (struct super_block *);
|
|
|
|
int (*show_options)(struct seq_file *, struct dentry *);
|
|
int (*show_devname)(struct seq_file *, struct dentry *);
|
|
int (*show_path)(struct seq_file *, struct dentry *);
|
|
int (*show_stats)(struct seq_file *, struct dentry *);
|
|
#ifdef CONFIG_QUOTA
|
|
ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
|
|
ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
|
|
#endif
|
|
int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
|
|
int (*nr_cached_objects)(struct super_block *);
|
|
void (*free_cached_objects)(struct super_block *, int);
|
|
};
|
|
|
|
/*
|
|
* Inode flags - they have no relation to superblock flags now
|
|
*/
|
|
#define S_SYNC 1 /* Writes are synced at once */
|
|
#define S_NOATIME 2 /* Do not update access times */
|
|
#define S_APPEND 4 /* Append-only file */
|
|
#define S_IMMUTABLE 8 /* Immutable file */
|
|
#define S_DEAD 16 /* removed, but still open directory */
|
|
#define S_NOQUOTA 32 /* Inode is not counted to quota */
|
|
#define S_DIRSYNC 64 /* Directory modifications are synchronous */
|
|
#define S_NOCMTIME 128 /* Do not update file c/mtime */
|
|
#define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
|
|
#define S_PRIVATE 512 /* Inode is fs-internal */
|
|
#define S_IMA 1024 /* Inode has an associated IMA struct */
|
|
#define S_AUTOMOUNT 2048 /* Automount/referral quasi-directory */
|
|
#define S_NOSEC 4096 /* no suid or xattr security attributes */
|
|
|
|
/*
|
|
* Note that nosuid etc flags are inode-specific: setting some file-system
|
|
* flags just means all the inodes inherit those flags by default. It might be
|
|
* possible to override it selectively if you really wanted to with some
|
|
* ioctl() that is not currently implemented.
|
|
*
|
|
* Exception: MS_RDONLY is always applied to the entire file system.
|
|
*
|
|
* Unfortunately, it is possible to change a filesystems flags with it mounted
|
|
* with files in use. This means that all of the inodes will not have their
|
|
* i_flags updated. Hence, i_flags no longer inherit the superblock mount
|
|
* flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
|
|
*/
|
|
#define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
|
|
|
|
#define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
|
|
#define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
|
|
((inode)->i_flags & S_SYNC))
|
|
#define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
|
|
((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
|
|
#define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
|
|
#define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
|
|
#define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION)
|
|
|
|
#define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
|
|
#define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
|
|
#define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
|
|
#define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
|
|
|
|
#define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
|
|
#define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
|
|
#define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
|
|
#define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
|
|
#define IS_IMA(inode) ((inode)->i_flags & S_IMA)
|
|
#define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
|
|
#define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
|
|
|
|
/*
|
|
* Inode state bits. Protected by inode->i_lock
|
|
*
|
|
* Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
|
|
* I_DIRTY_DATASYNC and I_DIRTY_PAGES.
|
|
*
|
|
* Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
|
|
* until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
|
|
* various stages of removing an inode.
|
|
*
|
|
* Two bits are used for locking and completion notification, I_NEW and I_SYNC.
|
|
*
|
|
* I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
|
|
* fdatasync(). i_atime is the usual cause.
|
|
* I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
|
|
* these changes separately from I_DIRTY_SYNC so that we
|
|
* don't have to write inode on fdatasync() when only
|
|
* mtime has changed in it.
|
|
* I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
|
|
* I_NEW Serves as both a mutex and completion notification.
|
|
* New inodes set I_NEW. If two processes both create
|
|
* the same inode, one of them will release its inode and
|
|
* wait for I_NEW to be released before returning.
|
|
* Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
|
|
* also cause waiting on I_NEW, without I_NEW actually
|
|
* being set. find_inode() uses this to prevent returning
|
|
* nearly-dead inodes.
|
|
* I_WILL_FREE Must be set when calling write_inode_now() if i_count
|
|
* is zero. I_FREEING must be set when I_WILL_FREE is
|
|
* cleared.
|
|
* I_FREEING Set when inode is about to be freed but still has dirty
|
|
* pages or buffers attached or the inode itself is still
|
|
* dirty.
|
|
* I_CLEAR Added by clear_inode(). In this state the inode is
|
|
* clean and can be destroyed. Inode keeps I_FREEING.
|
|
*
|
|
* Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
|
|
* prohibited for many purposes. iget() must wait for
|
|
* the inode to be completely released, then create it
|
|
* anew. Other functions will just ignore such inodes,
|
|
* if appropriate. I_NEW is used for waiting.
|
|
*
|
|
* I_SYNC Writeback of inode is running. The bit is set during
|
|
* data writeback, and cleared with a wakeup on the bit
|
|
* address once it is done. The bit is also used to pin
|
|
* the inode in memory for flusher thread.
|
|
*
|
|
* I_REFERENCED Marks the inode as recently references on the LRU list.
|
|
*
|
|
* I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
|
|
*
|
|
* Q: What is the difference between I_WILL_FREE and I_FREEING?
|
|
*/
|
|
#define I_DIRTY_SYNC (1 << 0)
|
|
#define I_DIRTY_DATASYNC (1 << 1)
|
|
#define I_DIRTY_PAGES (1 << 2)
|
|
#define __I_NEW 3
|
|
#define I_NEW (1 << __I_NEW)
|
|
#define I_WILL_FREE (1 << 4)
|
|
#define I_FREEING (1 << 5)
|
|
#define I_CLEAR (1 << 6)
|
|
#define __I_SYNC 7
|
|
#define I_SYNC (1 << __I_SYNC)
|
|
#define I_REFERENCED (1 << 8)
|
|
#define __I_DIO_WAKEUP 9
|
|
#define I_DIO_WAKEUP (1 << I_DIO_WAKEUP)
|
|
|
|
#define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
|
|
|
|
extern void __mark_inode_dirty(struct inode *, int);
|
|
static inline void mark_inode_dirty(struct inode *inode)
|
|
{
|
|
__mark_inode_dirty(inode, I_DIRTY);
|
|
}
|
|
|
|
static inline void mark_inode_dirty_sync(struct inode *inode)
|
|
{
|
|
__mark_inode_dirty(inode, I_DIRTY_SYNC);
|
|
}
|
|
|
|
extern void inc_nlink(struct inode *inode);
|
|
extern void drop_nlink(struct inode *inode);
|
|
extern void clear_nlink(struct inode *inode);
|
|
extern void set_nlink(struct inode *inode, unsigned int nlink);
|
|
|
|
static inline void inode_inc_link_count(struct inode *inode)
|
|
{
|
|
inc_nlink(inode);
|
|
mark_inode_dirty(inode);
|
|
}
|
|
|
|
static inline void inode_dec_link_count(struct inode *inode)
|
|
{
|
|
drop_nlink(inode);
|
|
mark_inode_dirty(inode);
|
|
}
|
|
|
|
/**
|
|
* inode_inc_iversion - increments i_version
|
|
* @inode: inode that need to be updated
|
|
*
|
|
* Every time the inode is modified, the i_version field will be incremented.
|
|
* The filesystem has to be mounted with i_version flag
|
|
*/
|
|
|
|
static inline void inode_inc_iversion(struct inode *inode)
|
|
{
|
|
spin_lock(&inode->i_lock);
|
|
inode->i_version++;
|
|
spin_unlock(&inode->i_lock);
|
|
}
|
|
|
|
enum file_time_flags {
|
|
S_ATIME = 1,
|
|
S_MTIME = 2,
|
|
S_CTIME = 4,
|
|
S_VERSION = 8,
|
|
};
|
|
|
|
extern void touch_atime(struct path *);
|
|
static inline void file_accessed(struct file *file)
|
|
{
|
|
if (!(file->f_flags & O_NOATIME))
|
|
touch_atime(&file->f_path);
|
|
}
|
|
|
|
int sync_inode(struct inode *inode, struct writeback_control *wbc);
|
|
int sync_inode_metadata(struct inode *inode, int wait);
|
|
|
|
struct file_system_type {
|
|
const char *name;
|
|
int fs_flags;
|
|
#define FS_REQUIRES_DEV 1
|
|
#define FS_BINARY_MOUNTDATA 2
|
|
#define FS_HAS_SUBTYPE 4
|
|
#define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
|
|
#define FS_USERNS_DEV_MOUNT 16 /* A userns mount does not imply MNT_NODEV */
|
|
#define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
|
|
struct dentry *(*mount) (struct file_system_type *, int,
|
|
const char *, void *);
|
|
void (*kill_sb) (struct super_block *);
|
|
struct module *owner;
|
|
struct file_system_type * next;
|
|
struct hlist_head fs_supers;
|
|
|
|
struct lock_class_key s_lock_key;
|
|
struct lock_class_key s_umount_key;
|
|
struct lock_class_key s_vfs_rename_key;
|
|
struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
|
|
|
|
struct lock_class_key i_lock_key;
|
|
struct lock_class_key i_mutex_key;
|
|
struct lock_class_key i_mutex_dir_key;
|
|
};
|
|
|
|
#define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
|
|
|
|
extern struct dentry *mount_ns(struct file_system_type *fs_type, int flags,
|
|
void *data, int (*fill_super)(struct super_block *, void *, int));
|
|
extern struct dentry *mount_bdev(struct file_system_type *fs_type,
|
|
int flags, const char *dev_name, void *data,
|
|
int (*fill_super)(struct super_block *, void *, int));
|
|
extern struct dentry *mount_single(struct file_system_type *fs_type,
|
|
int flags, void *data,
|
|
int (*fill_super)(struct super_block *, void *, int));
|
|
extern struct dentry *mount_nodev(struct file_system_type *fs_type,
|
|
int flags, void *data,
|
|
int (*fill_super)(struct super_block *, void *, int));
|
|
extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
|
|
void generic_shutdown_super(struct super_block *sb);
|
|
void kill_block_super(struct super_block *sb);
|
|
void kill_anon_super(struct super_block *sb);
|
|
void kill_litter_super(struct super_block *sb);
|
|
void deactivate_super(struct super_block *sb);
|
|
void deactivate_locked_super(struct super_block *sb);
|
|
int set_anon_super(struct super_block *s, void *data);
|
|
int get_anon_bdev(dev_t *);
|
|
void free_anon_bdev(dev_t);
|
|
struct super_block *sget(struct file_system_type *type,
|
|
int (*test)(struct super_block *,void *),
|
|
int (*set)(struct super_block *,void *),
|
|
int flags, void *data);
|
|
extern struct dentry *mount_pseudo(struct file_system_type *, char *,
|
|
const struct super_operations *ops,
|
|
const struct dentry_operations *dops,
|
|
unsigned long);
|
|
|
|
/* Alas, no aliases. Too much hassle with bringing module.h everywhere */
|
|
#define fops_get(fops) \
|
|
(((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
|
|
#define fops_put(fops) \
|
|
do { if (fops) module_put((fops)->owner); } while(0)
|
|
|
|
extern int register_filesystem(struct file_system_type *);
|
|
extern int unregister_filesystem(struct file_system_type *);
|
|
extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
|
|
#define kern_mount(type) kern_mount_data(type, NULL)
|
|
extern void kern_unmount(struct vfsmount *mnt);
|
|
extern int may_umount_tree(struct vfsmount *);
|
|
extern int may_umount(struct vfsmount *);
|
|
extern long do_mount(const char *, const char *, const char *, unsigned long, void *);
|
|
extern struct vfsmount *collect_mounts(struct path *);
|
|
extern void drop_collected_mounts(struct vfsmount *);
|
|
extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
|
|
struct vfsmount *);
|
|
extern int vfs_statfs(struct path *, struct kstatfs *);
|
|
extern int user_statfs(const char __user *, struct kstatfs *);
|
|
extern int fd_statfs(int, struct kstatfs *);
|
|
extern int vfs_ustat(dev_t, struct kstatfs *);
|
|
extern int freeze_super(struct super_block *super);
|
|
extern int thaw_super(struct super_block *super);
|
|
extern bool our_mnt(struct vfsmount *mnt);
|
|
|
|
extern int current_umask(void);
|
|
|
|
/* /sys/fs */
|
|
extern struct kobject *fs_kobj;
|
|
|
|
#define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK)
|
|
extern int rw_verify_area(int, struct file *, loff_t *, size_t);
|
|
|
|
#define FLOCK_VERIFY_READ 1
|
|
#define FLOCK_VERIFY_WRITE 2
|
|
|
|
#ifdef CONFIG_FILE_LOCKING
|
|
extern int locks_mandatory_locked(struct inode *);
|
|
extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
|
|
|
|
/*
|
|
* Candidates for mandatory locking have the setgid bit set
|
|
* but no group execute bit - an otherwise meaningless combination.
|
|
*/
|
|
|
|
static inline int __mandatory_lock(struct inode *ino)
|
|
{
|
|
return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
|
|
}
|
|
|
|
/*
|
|
* ... and these candidates should be on MS_MANDLOCK mounted fs,
|
|
* otherwise these will be advisory locks
|
|
*/
|
|
|
|
static inline int mandatory_lock(struct inode *ino)
|
|
{
|
|
return IS_MANDLOCK(ino) && __mandatory_lock(ino);
|
|
}
|
|
|
|
static inline int locks_verify_locked(struct inode *inode)
|
|
{
|
|
if (mandatory_lock(inode))
|
|
return locks_mandatory_locked(inode);
|
|
return 0;
|
|
}
|
|
|
|
static inline int locks_verify_truncate(struct inode *inode,
|
|
struct file *filp,
|
|
loff_t size)
|
|
{
|
|
if (inode->i_flock && mandatory_lock(inode))
|
|
return locks_mandatory_area(
|
|
FLOCK_VERIFY_WRITE, inode, filp,
|
|
size < inode->i_size ? size : inode->i_size,
|
|
(size < inode->i_size ? inode->i_size - size
|
|
: size - inode->i_size)
|
|
);
|
|
return 0;
|
|
}
|
|
|
|
static inline int break_lease(struct inode *inode, unsigned int mode)
|
|
{
|
|
if (inode->i_flock)
|
|
return __break_lease(inode, mode);
|
|
return 0;
|
|
}
|
|
#else /* !CONFIG_FILE_LOCKING */
|
|
static inline int locks_mandatory_locked(struct inode *inode)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int locks_mandatory_area(int rw, struct inode *inode,
|
|
struct file *filp, loff_t offset,
|
|
size_t count)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int __mandatory_lock(struct inode *inode)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int mandatory_lock(struct inode *inode)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int locks_verify_locked(struct inode *inode)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int locks_verify_truncate(struct inode *inode, struct file *filp,
|
|
size_t size)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int break_lease(struct inode *inode, unsigned int mode)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
#endif /* CONFIG_FILE_LOCKING */
|
|
|
|
/* fs/open.c */
|
|
struct audit_names;
|
|
struct filename {
|
|
const char *name; /* pointer to actual string */
|
|
const __user char *uptr; /* original userland pointer */
|
|
struct audit_names *aname;
|
|
bool separate; /* should "name" be freed? */
|
|
};
|
|
|
|
extern long vfs_truncate(struct path *, loff_t);
|
|
extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
|
|
struct file *filp);
|
|
extern int do_fallocate(struct file *file, int mode, loff_t offset,
|
|
loff_t len);
|
|
extern long do_sys_open(int dfd, const char __user *filename, int flags,
|
|
umode_t mode);
|
|
extern struct file *file_open_name(struct filename *, int, umode_t);
|
|
extern struct file *filp_open(const char *, int, umode_t);
|
|
extern struct file *file_open_root(struct dentry *, struct vfsmount *,
|
|
const char *, int);
|
|
extern struct file * dentry_open(const struct path *, int, const struct cred *);
|
|
extern int filp_close(struct file *, fl_owner_t id);
|
|
|
|
extern struct filename *getname(const char __user *);
|
|
|
|
enum {
|
|
FILE_CREATED = 1,
|
|
FILE_OPENED = 2
|
|
};
|
|
extern int finish_open(struct file *file, struct dentry *dentry,
|
|
int (*open)(struct inode *, struct file *),
|
|
int *opened);
|
|
extern int finish_no_open(struct file *file, struct dentry *dentry);
|
|
|
|
/* fs/ioctl.c */
|
|
|
|
extern int ioctl_preallocate(struct file *filp, void __user *argp);
|
|
|
|
/* fs/dcache.c */
|
|
extern void __init vfs_caches_init_early(void);
|
|
extern void __init vfs_caches_init(unsigned long);
|
|
|
|
extern struct kmem_cache *names_cachep;
|
|
|
|
extern void final_putname(struct filename *name);
|
|
|
|
#define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
|
|
#define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
|
|
#ifndef CONFIG_AUDITSYSCALL
|
|
#define putname(name) final_putname(name)
|
|
#else
|
|
extern void putname(struct filename *name);
|
|
#endif
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
extern int register_blkdev(unsigned int, const char *);
|
|
extern void unregister_blkdev(unsigned int, const char *);
|
|
extern struct block_device *bdget(dev_t);
|
|
extern struct block_device *bdgrab(struct block_device *bdev);
|
|
extern void bd_set_size(struct block_device *, loff_t size);
|
|
extern void bd_forget(struct inode *inode);
|
|
extern void bdput(struct block_device *);
|
|
extern void invalidate_bdev(struct block_device *);
|
|
extern void iterate_bdevs(void (*)(struct block_device *, void *), void *);
|
|
extern int sync_blockdev(struct block_device *bdev);
|
|
extern void kill_bdev(struct block_device *);
|
|
extern struct super_block *freeze_bdev(struct block_device *);
|
|
extern void emergency_thaw_all(void);
|
|
extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
|
|
extern int fsync_bdev(struct block_device *);
|
|
#else
|
|
static inline void bd_forget(struct inode *inode) {}
|
|
static inline int sync_blockdev(struct block_device *bdev) { return 0; }
|
|
static inline void kill_bdev(struct block_device *bdev) {}
|
|
static inline void invalidate_bdev(struct block_device *bdev) {}
|
|
|
|
static inline struct super_block *freeze_bdev(struct block_device *sb)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg)
|
|
{
|
|
}
|
|
#endif
|
|
extern int sync_filesystem(struct super_block *);
|
|
extern const struct file_operations def_blk_fops;
|
|
extern const struct file_operations def_chr_fops;
|
|
extern const struct file_operations bad_sock_fops;
|
|
#ifdef CONFIG_BLOCK
|
|
extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
|
|
extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long);
|
|
extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
|
|
extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
|
|
extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
|
|
void *holder);
|
|
extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
|
|
void *holder);
|
|
extern void blkdev_put(struct block_device *bdev, fmode_t mode);
|
|
#ifdef CONFIG_SYSFS
|
|
extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
|
|
extern void bd_unlink_disk_holder(struct block_device *bdev,
|
|
struct gendisk *disk);
|
|
#else
|
|
static inline int bd_link_disk_holder(struct block_device *bdev,
|
|
struct gendisk *disk)
|
|
{
|
|
return 0;
|
|
}
|
|
static inline void bd_unlink_disk_holder(struct block_device *bdev,
|
|
struct gendisk *disk)
|
|
{
|
|
}
|
|
#endif
|
|
#endif
|
|
|
|
/* fs/char_dev.c */
|
|
#define CHRDEV_MAJOR_HASH_SIZE 255
|
|
extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
|
|
extern int register_chrdev_region(dev_t, unsigned, const char *);
|
|
extern int __register_chrdev(unsigned int major, unsigned int baseminor,
|
|
unsigned int count, const char *name,
|
|
const struct file_operations *fops);
|
|
extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
|
|
unsigned int count, const char *name);
|
|
extern void unregister_chrdev_region(dev_t, unsigned);
|
|
extern void chrdev_show(struct seq_file *,off_t);
|
|
|
|
static inline int register_chrdev(unsigned int major, const char *name,
|
|
const struct file_operations *fops)
|
|
{
|
|
return __register_chrdev(major, 0, 256, name, fops);
|
|
}
|
|
|
|
static inline void unregister_chrdev(unsigned int major, const char *name)
|
|
{
|
|
__unregister_chrdev(major, 0, 256, name);
|
|
}
|
|
|
|
/* fs/block_dev.c */
|
|
#define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
|
|
#define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
#define BLKDEV_MAJOR_HASH_SIZE 255
|
|
extern const char *__bdevname(dev_t, char *buffer);
|
|
extern const char *bdevname(struct block_device *bdev, char *buffer);
|
|
extern struct block_device *lookup_bdev(const char *);
|
|
extern void blkdev_show(struct seq_file *,off_t);
|
|
|
|
#else
|
|
#define BLKDEV_MAJOR_HASH_SIZE 0
|
|
#endif
|
|
|
|
extern void init_special_inode(struct inode *, umode_t, dev_t);
|
|
|
|
/* Invalid inode operations -- fs/bad_inode.c */
|
|
extern void make_bad_inode(struct inode *);
|
|
extern int is_bad_inode(struct inode *);
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
/*
|
|
* return READ, READA, or WRITE
|
|
*/
|
|
#define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
|
|
|
|
/*
|
|
* return data direction, READ or WRITE
|
|
*/
|
|
#define bio_data_dir(bio) ((bio)->bi_rw & 1)
|
|
|
|
extern void check_disk_size_change(struct gendisk *disk,
|
|
struct block_device *bdev);
|
|
extern int revalidate_disk(struct gendisk *);
|
|
extern int check_disk_change(struct block_device *);
|
|
extern int __invalidate_device(struct block_device *, bool);
|
|
extern int invalidate_partition(struct gendisk *, int);
|
|
#endif
|
|
unsigned long invalidate_mapping_pages(struct address_space *mapping,
|
|
pgoff_t start, pgoff_t end);
|
|
|
|
static inline void invalidate_remote_inode(struct inode *inode)
|
|
{
|
|
if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
|
|
S_ISLNK(inode->i_mode))
|
|
invalidate_mapping_pages(inode->i_mapping, 0, -1);
|
|
}
|
|
extern int invalidate_inode_pages2(struct address_space *mapping);
|
|
extern int invalidate_inode_pages2_range(struct address_space *mapping,
|
|
pgoff_t start, pgoff_t end);
|
|
extern int write_inode_now(struct inode *, int);
|
|
extern int filemap_fdatawrite(struct address_space *);
|
|
extern int filemap_flush(struct address_space *);
|
|
extern int filemap_fdatawait(struct address_space *);
|
|
extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
|
|
loff_t lend);
|
|
extern int filemap_write_and_wait(struct address_space *mapping);
|
|
extern int filemap_write_and_wait_range(struct address_space *mapping,
|
|
loff_t lstart, loff_t lend);
|
|
extern int __filemap_fdatawrite_range(struct address_space *mapping,
|
|
loff_t start, loff_t end, int sync_mode);
|
|
extern int filemap_fdatawrite_range(struct address_space *mapping,
|
|
loff_t start, loff_t end);
|
|
|
|
extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
|
|
int datasync);
|
|
extern int vfs_fsync(struct file *file, int datasync);
|
|
extern int generic_write_sync(struct file *file, loff_t pos, loff_t count);
|
|
extern void emergency_sync(void);
|
|
extern void emergency_remount(void);
|
|
#ifdef CONFIG_BLOCK
|
|
extern sector_t bmap(struct inode *, sector_t);
|
|
#endif
|
|
extern int notify_change(struct dentry *, struct iattr *);
|
|
extern int inode_permission(struct inode *, int);
|
|
extern int generic_permission(struct inode *, int);
|
|
|
|
static inline bool execute_ok(struct inode *inode)
|
|
{
|
|
return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
|
|
}
|
|
|
|
static inline struct inode *file_inode(struct file *f)
|
|
{
|
|
return f->f_inode;
|
|
}
|
|
|
|
static inline void file_start_write(struct file *file)
|
|
{
|
|
if (!S_ISREG(file_inode(file)->i_mode))
|
|
return;
|
|
__sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true);
|
|
}
|
|
|
|
static inline bool file_start_write_trylock(struct file *file)
|
|
{
|
|
if (!S_ISREG(file_inode(file)->i_mode))
|
|
return true;
|
|
return __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, false);
|
|
}
|
|
|
|
static inline void file_end_write(struct file *file)
|
|
{
|
|
if (!S_ISREG(file_inode(file)->i_mode))
|
|
return;
|
|
__sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
|
|
}
|
|
|
|
/*
|
|
* get_write_access() gets write permission for a file.
|
|
* put_write_access() releases this write permission.
|
|
* This is used for regular files.
|
|
* We cannot support write (and maybe mmap read-write shared) accesses and
|
|
* MAP_DENYWRITE mmappings simultaneously. The i_writecount field of an inode
|
|
* can have the following values:
|
|
* 0: no writers, no VM_DENYWRITE mappings
|
|
* < 0: (-i_writecount) vm_area_structs with VM_DENYWRITE set exist
|
|
* > 0: (i_writecount) users are writing to the file.
|
|
*
|
|
* Normally we operate on that counter with atomic_{inc,dec} and it's safe
|
|
* except for the cases where we don't hold i_writecount yet. Then we need to
|
|
* use {get,deny}_write_access() - these functions check the sign and refuse
|
|
* to do the change if sign is wrong.
|
|
*/
|
|
static inline int get_write_access(struct inode *inode)
|
|
{
|
|
return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
|
|
}
|
|
static inline int deny_write_access(struct file *file)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
|
|
}
|
|
static inline void put_write_access(struct inode * inode)
|
|
{
|
|
atomic_dec(&inode->i_writecount);
|
|
}
|
|
static inline void allow_write_access(struct file *file)
|
|
{
|
|
if (file)
|
|
atomic_inc(&file_inode(file)->i_writecount);
|
|
}
|
|
#ifdef CONFIG_IMA
|
|
static inline void i_readcount_dec(struct inode *inode)
|
|
{
|
|
BUG_ON(!atomic_read(&inode->i_readcount));
|
|
atomic_dec(&inode->i_readcount);
|
|
}
|
|
static inline void i_readcount_inc(struct inode *inode)
|
|
{
|
|
atomic_inc(&inode->i_readcount);
|
|
}
|
|
#else
|
|
static inline void i_readcount_dec(struct inode *inode)
|
|
{
|
|
return;
|
|
}
|
|
static inline void i_readcount_inc(struct inode *inode)
|
|
{
|
|
return;
|
|
}
|
|
#endif
|
|
extern int do_pipe_flags(int *, int);
|
|
|
|
extern int kernel_read(struct file *, loff_t, char *, unsigned long);
|
|
extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
|
|
extern struct file * open_exec(const char *);
|
|
|
|
/* fs/dcache.c -- generic fs support functions */
|
|
extern int is_subdir(struct dentry *, struct dentry *);
|
|
extern int path_is_under(struct path *, struct path *);
|
|
extern ino_t find_inode_number(struct dentry *, struct qstr *);
|
|
|
|
#include <linux/err.h>
|
|
|
|
/* needed for stackable file system support */
|
|
extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
|
|
|
|
extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
|
|
|
|
extern int inode_init_always(struct super_block *, struct inode *);
|
|
extern void inode_init_once(struct inode *);
|
|
extern void address_space_init_once(struct address_space *mapping);
|
|
extern void ihold(struct inode * inode);
|
|
extern void iput(struct inode *);
|
|
extern struct inode * igrab(struct inode *);
|
|
extern ino_t iunique(struct super_block *, ino_t);
|
|
extern int inode_needs_sync(struct inode *inode);
|
|
extern int generic_delete_inode(struct inode *inode);
|
|
static inline int generic_drop_inode(struct inode *inode)
|
|
{
|
|
return !inode->i_nlink || inode_unhashed(inode);
|
|
}
|
|
|
|
extern struct inode *ilookup5_nowait(struct super_block *sb,
|
|
unsigned long hashval, int (*test)(struct inode *, void *),
|
|
void *data);
|
|
extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
|
|
int (*test)(struct inode *, void *), void *data);
|
|
extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
|
|
|
|
extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
|
|
extern struct inode * iget_locked(struct super_block *, unsigned long);
|
|
extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
|
|
extern int insert_inode_locked(struct inode *);
|
|
#ifdef CONFIG_DEBUG_LOCK_ALLOC
|
|
extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
|
|
#else
|
|
static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
|
|
#endif
|
|
extern void unlock_new_inode(struct inode *);
|
|
extern unsigned int get_next_ino(void);
|
|
|
|
extern void __iget(struct inode * inode);
|
|
extern void iget_failed(struct inode *);
|
|
extern void clear_inode(struct inode *);
|
|
extern void __destroy_inode(struct inode *);
|
|
extern struct inode *new_inode_pseudo(struct super_block *sb);
|
|
extern struct inode *new_inode(struct super_block *sb);
|
|
extern void free_inode_nonrcu(struct inode *inode);
|
|
extern int should_remove_suid(struct dentry *);
|
|
extern int file_remove_suid(struct file *);
|
|
|
|
extern void __insert_inode_hash(struct inode *, unsigned long hashval);
|
|
static inline void insert_inode_hash(struct inode *inode)
|
|
{
|
|
__insert_inode_hash(inode, inode->i_ino);
|
|
}
|
|
|
|
extern void __remove_inode_hash(struct inode *);
|
|
static inline void remove_inode_hash(struct inode *inode)
|
|
{
|
|
if (!inode_unhashed(inode))
|
|
__remove_inode_hash(inode);
|
|
}
|
|
|
|
extern void inode_sb_list_add(struct inode *inode);
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
extern void submit_bio(int, struct bio *);
|
|
extern int bdev_read_only(struct block_device *);
|
|
#endif
|
|
extern int set_blocksize(struct block_device *, int);
|
|
extern int sb_set_blocksize(struct super_block *, int);
|
|
extern int sb_min_blocksize(struct super_block *, int);
|
|
|
|
extern int generic_file_mmap(struct file *, struct vm_area_struct *);
|
|
extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
|
|
extern int generic_file_remap_pages(struct vm_area_struct *, unsigned long addr,
|
|
unsigned long size, pgoff_t pgoff);
|
|
extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
|
|
int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
|
|
extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
|
|
extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long,
|
|
loff_t *);
|
|
extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
|
|
extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
|
|
unsigned long *, loff_t, loff_t *, size_t, size_t);
|
|
extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
|
|
unsigned long, loff_t, loff_t *, size_t, ssize_t);
|
|
extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
|
|
extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
|
|
extern int generic_segment_checks(const struct iovec *iov,
|
|
unsigned long *nr_segs, size_t *count, int access_flags);
|
|
|
|
/* fs/block_dev.c */
|
|
extern ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
|
|
unsigned long nr_segs, loff_t pos);
|
|
extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
|
|
int datasync);
|
|
extern void block_sync_page(struct page *page);
|
|
|
|
/* fs/splice.c */
|
|
extern ssize_t generic_file_splice_read(struct file *, loff_t *,
|
|
struct pipe_inode_info *, size_t, unsigned int);
|
|
extern ssize_t default_file_splice_read(struct file *, loff_t *,
|
|
struct pipe_inode_info *, size_t, unsigned int);
|
|
extern ssize_t generic_file_splice_write(struct pipe_inode_info *,
|
|
struct file *, loff_t *, size_t, unsigned int);
|
|
extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
|
|
struct file *out, loff_t *, size_t len, unsigned int flags);
|
|
|
|
extern void
|
|
file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
|
|
extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
|
|
extern loff_t no_llseek(struct file *file, loff_t offset, int whence);
|
|
extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
|
|
extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
|
|
int whence, loff_t maxsize, loff_t eof);
|
|
extern int generic_file_open(struct inode * inode, struct file * filp);
|
|
extern int nonseekable_open(struct inode * inode, struct file * filp);
|
|
|
|
#ifdef CONFIG_FS_XIP
|
|
extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
|
|
loff_t *ppos);
|
|
extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
|
|
extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
|
|
size_t len, loff_t *ppos);
|
|
extern int xip_truncate_page(struct address_space *mapping, loff_t from);
|
|
#else
|
|
static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode,
|
|
loff_t file_offset);
|
|
|
|
enum {
|
|
/* need locking between buffered and direct access */
|
|
DIO_LOCKING = 0x01,
|
|
|
|
/* filesystem does not support filling holes */
|
|
DIO_SKIP_HOLES = 0x02,
|
|
};
|
|
|
|
void dio_end_io(struct bio *bio, int error);
|
|
|
|
ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
|
|
struct block_device *bdev, const struct iovec *iov, loff_t offset,
|
|
unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io,
|
|
dio_submit_t submit_io, int flags);
|
|
|
|
static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
|
|
struct inode *inode, const struct iovec *iov, loff_t offset,
|
|
unsigned long nr_segs, get_block_t get_block)
|
|
{
|
|
return __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
|
|
offset, nr_segs, get_block, NULL, NULL,
|
|
DIO_LOCKING | DIO_SKIP_HOLES);
|
|
}
|
|
#endif
|
|
|
|
void inode_dio_wait(struct inode *inode);
|
|
void inode_dio_done(struct inode *inode);
|
|
|
|
extern const struct file_operations generic_ro_fops;
|
|
|
|
#define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
|
|
|
|
extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
|
|
extern int vfs_follow_link(struct nameidata *, const char *);
|
|
extern int page_readlink(struct dentry *, char __user *, int);
|
|
extern void *page_follow_link_light(struct dentry *, struct nameidata *);
|
|
extern void page_put_link(struct dentry *, struct nameidata *, void *);
|
|
extern int __page_symlink(struct inode *inode, const char *symname, int len,
|
|
int nofs);
|
|
extern int page_symlink(struct inode *inode, const char *symname, int len);
|
|
extern const struct inode_operations page_symlink_inode_operations;
|
|
extern int generic_readlink(struct dentry *, char __user *, int);
|
|
extern void generic_fillattr(struct inode *, struct kstat *);
|
|
extern int vfs_getattr(struct path *, struct kstat *);
|
|
void __inode_add_bytes(struct inode *inode, loff_t bytes);
|
|
void inode_add_bytes(struct inode *inode, loff_t bytes);
|
|
void inode_sub_bytes(struct inode *inode, loff_t bytes);
|
|
loff_t inode_get_bytes(struct inode *inode);
|
|
void inode_set_bytes(struct inode *inode, loff_t bytes);
|
|
|
|
extern int vfs_readdir(struct file *, filldir_t, void *);
|
|
|
|
extern int vfs_stat(const char __user *, struct kstat *);
|
|
extern int vfs_lstat(const char __user *, struct kstat *);
|
|
extern int vfs_fstat(unsigned int, struct kstat *);
|
|
extern int vfs_fstatat(int , const char __user *, struct kstat *, int);
|
|
|
|
extern int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
|
|
unsigned long arg);
|
|
extern int __generic_block_fiemap(struct inode *inode,
|
|
struct fiemap_extent_info *fieinfo,
|
|
loff_t start, loff_t len,
|
|
get_block_t *get_block);
|
|
extern int generic_block_fiemap(struct inode *inode,
|
|
struct fiemap_extent_info *fieinfo, u64 start,
|
|
u64 len, get_block_t *get_block);
|
|
|
|
extern void get_filesystem(struct file_system_type *fs);
|
|
extern void put_filesystem(struct file_system_type *fs);
|
|
extern struct file_system_type *get_fs_type(const char *name);
|
|
extern struct super_block *get_super(struct block_device *);
|
|
extern struct super_block *get_super_thawed(struct block_device *);
|
|
extern struct super_block *get_active_super(struct block_device *bdev);
|
|
extern void drop_super(struct super_block *sb);
|
|
extern void iterate_supers(void (*)(struct super_block *, void *), void *);
|
|
extern void iterate_supers_type(struct file_system_type *,
|
|
void (*)(struct super_block *, void *), void *);
|
|
|
|
extern int dcache_dir_open(struct inode *, struct file *);
|
|
extern int dcache_dir_close(struct inode *, struct file *);
|
|
extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
|
|
extern int dcache_readdir(struct file *, void *, filldir_t);
|
|
extern int simple_setattr(struct dentry *, struct iattr *);
|
|
extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
|
|
extern int simple_statfs(struct dentry *, struct kstatfs *);
|
|
extern int simple_open(struct inode *inode, struct file *file);
|
|
extern int simple_link(struct dentry *, struct inode *, struct dentry *);
|
|
extern int simple_unlink(struct inode *, struct dentry *);
|
|
extern int simple_rmdir(struct inode *, struct dentry *);
|
|
extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
|
|
extern int noop_fsync(struct file *, loff_t, loff_t, int);
|
|
extern int simple_empty(struct dentry *);
|
|
extern int simple_readpage(struct file *file, struct page *page);
|
|
extern int simple_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata);
|
|
extern int simple_write_end(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata);
|
|
|
|
extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
|
|
extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
|
|
extern const struct file_operations simple_dir_operations;
|
|
extern const struct inode_operations simple_dir_inode_operations;
|
|
struct tree_descr { char *name; const struct file_operations *ops; int mode; };
|
|
struct dentry *d_alloc_name(struct dentry *, const char *);
|
|
extern int simple_fill_super(struct super_block *, unsigned long, struct tree_descr *);
|
|
extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
|
|
extern void simple_release_fs(struct vfsmount **mount, int *count);
|
|
|
|
extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
|
|
loff_t *ppos, const void *from, size_t available);
|
|
extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
|
|
const void __user *from, size_t count);
|
|
|
|
extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
|
|
|
|
extern int generic_check_addressable(unsigned, u64);
|
|
|
|
#ifdef CONFIG_MIGRATION
|
|
extern int buffer_migrate_page(struct address_space *,
|
|
struct page *, struct page *,
|
|
enum migrate_mode);
|
|
#else
|
|
#define buffer_migrate_page NULL
|
|
#endif
|
|
|
|
extern int inode_change_ok(const struct inode *, struct iattr *);
|
|
extern int inode_newsize_ok(const struct inode *, loff_t offset);
|
|
extern void setattr_copy(struct inode *inode, const struct iattr *attr);
|
|
|
|
extern int file_update_time(struct file *file);
|
|
|
|
extern int generic_show_options(struct seq_file *m, struct dentry *root);
|
|
extern void save_mount_options(struct super_block *sb, char *options);
|
|
extern void replace_mount_options(struct super_block *sb, char *options);
|
|
|
|
static inline ino_t parent_ino(struct dentry *dentry)
|
|
{
|
|
ino_t res;
|
|
|
|
/*
|
|
* Don't strictly need d_lock here? If the parent ino could change
|
|
* then surely we'd have a deeper race in the caller?
|
|
*/
|
|
spin_lock(&dentry->d_lock);
|
|
res = dentry->d_parent->d_inode->i_ino;
|
|
spin_unlock(&dentry->d_lock);
|
|
return res;
|
|
}
|
|
|
|
/* Transaction based IO helpers */
|
|
|
|
/*
|
|
* An argresp is stored in an allocated page and holds the
|
|
* size of the argument or response, along with its content
|
|
*/
|
|
struct simple_transaction_argresp {
|
|
ssize_t size;
|
|
char data[0];
|
|
};
|
|
|
|
#define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
|
|
|
|
char *simple_transaction_get(struct file *file, const char __user *buf,
|
|
size_t size);
|
|
ssize_t simple_transaction_read(struct file *file, char __user *buf,
|
|
size_t size, loff_t *pos);
|
|
int simple_transaction_release(struct inode *inode, struct file *file);
|
|
|
|
void simple_transaction_set(struct file *file, size_t n);
|
|
|
|
/*
|
|
* simple attribute files
|
|
*
|
|
* These attributes behave similar to those in sysfs:
|
|
*
|
|
* Writing to an attribute immediately sets a value, an open file can be
|
|
* written to multiple times.
|
|
*
|
|
* Reading from an attribute creates a buffer from the value that might get
|
|
* read with multiple read calls. When the attribute has been read
|
|
* completely, no further read calls are possible until the file is opened
|
|
* again.
|
|
*
|
|
* All attributes contain a text representation of a numeric value
|
|
* that are accessed with the get() and set() functions.
|
|
*/
|
|
#define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
|
|
static int __fops ## _open(struct inode *inode, struct file *file) \
|
|
{ \
|
|
__simple_attr_check_format(__fmt, 0ull); \
|
|
return simple_attr_open(inode, file, __get, __set, __fmt); \
|
|
} \
|
|
static const struct file_operations __fops = { \
|
|
.owner = THIS_MODULE, \
|
|
.open = __fops ## _open, \
|
|
.release = simple_attr_release, \
|
|
.read = simple_attr_read, \
|
|
.write = simple_attr_write, \
|
|
.llseek = generic_file_llseek, \
|
|
};
|
|
|
|
static inline __printf(1, 2)
|
|
void __simple_attr_check_format(const char *fmt, ...)
|
|
{
|
|
/* don't do anything, just let the compiler check the arguments; */
|
|
}
|
|
|
|
int simple_attr_open(struct inode *inode, struct file *file,
|
|
int (*get)(void *, u64 *), int (*set)(void *, u64),
|
|
const char *fmt);
|
|
int simple_attr_release(struct inode *inode, struct file *file);
|
|
ssize_t simple_attr_read(struct file *file, char __user *buf,
|
|
size_t len, loff_t *ppos);
|
|
ssize_t simple_attr_write(struct file *file, const char __user *buf,
|
|
size_t len, loff_t *ppos);
|
|
|
|
struct ctl_table;
|
|
int proc_nr_files(struct ctl_table *table, int write,
|
|
void __user *buffer, size_t *lenp, loff_t *ppos);
|
|
int proc_nr_dentry(struct ctl_table *table, int write,
|
|
void __user *buffer, size_t *lenp, loff_t *ppos);
|
|
int proc_nr_inodes(struct ctl_table *table, int write,
|
|
void __user *buffer, size_t *lenp, loff_t *ppos);
|
|
int __init get_filesystem_list(char *buf);
|
|
|
|
#define __FMODE_EXEC ((__force int) FMODE_EXEC)
|
|
#define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
|
|
|
|
#define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
|
|
#define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
|
|
(flag & __FMODE_NONOTIFY)))
|
|
|
|
static inline int is_sxid(umode_t mode)
|
|
{
|
|
return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
|
|
}
|
|
|
|
static inline void inode_has_no_xattr(struct inode *inode)
|
|
{
|
|
if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & MS_NOSEC))
|
|
inode->i_flags |= S_NOSEC;
|
|
}
|
|
|
|
#endif /* _LINUX_FS_H */
|