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On networked filesystems file data can be changed externally. FUSE provides notification messages for filesystem to inform kernel that metadata or data region of a file needs to be invalidated in local page cache. That provides the basis for filesystem implementations to invalidate kernel cache explicitly based on observed filesystem-specific events. FUSE has also "automatic" invalidation mode(*) when the kernel automatically invalidates data cache of a file if it sees mtime change. It also automatically invalidates whole data cache of a file if it sees file size being changed. The automatic mode has corresponding capability - FUSE_AUTO_INVAL_DATA. However, due to probably historical reason, that capability controls only whether mtime change should be resulting in automatic invalidation or not. A change in file size always results in invalidating whole data cache of a file irregardless of whether FUSE_AUTO_INVAL_DATA was negotiated(+). The filesystem I write[1] represents data arrays stored in networked database as local files suitable for mmap. It is read-only filesystem - changes to data are committed externally via database interfaces and the filesystem only glues data into contiguous file streams suitable for mmap and traditional array processing. The files are big - starting from hundreds gigabytes and more. The files change regularly, and frequently by data being appended to their end. The size of files thus changes frequently. If a file was accessed locally and some part of its data got into page cache, we want that data to stay cached unless there is memory pressure, or unless corresponding part of the file was actually changed. However current FUSE behaviour - when it sees file size change - is to invalidate the whole file. The data cache of the file is thus completely lost even on small size change, and despite that the filesystem server is careful to accurately translate database changes into FUSE invalidation messages to kernel. Let's fix it: if a filesystem, through new FUSE_EXPLICIT_INVAL_DATA capability, indicates to kernel that it is fully responsible for data cache invalidation, then the kernel won't invalidate files data cache on size change and only truncate that cache to new size in case the size decreased. (*) see72d0d248ca
"fuse: add FUSE_AUTO_INVAL_DATA init flag",eed2179efe
"fuse: invalidate inode mapping if mtime changes" (+) in writeback mode the kernel does not invalidate data cache on file size change, but neither it allows the filesystem to set the size due to external event (see8373200b12
"fuse: Trust kernel i_size only") [1] https://lab.nexedi.com/kirr/wendelin.core/blob/a50f1d9f/wcfs/wcfs.go#L20 Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
1097 lines
26 KiB
C
1097 lines
26 KiB
C
/*
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FUSE: Filesystem in Userspace
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Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
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This program can be distributed under the terms of the GNU GPL.
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See the file COPYING.
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*/
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#ifndef _FS_FUSE_I_H
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#define _FS_FUSE_I_H
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#ifndef pr_fmt
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# define pr_fmt(fmt) "fuse: " fmt
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#endif
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#include <linux/fuse.h>
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#include <linux/fs.h>
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#include <linux/mount.h>
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#include <linux/wait.h>
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#include <linux/list.h>
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#include <linux/spinlock.h>
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#include <linux/mm.h>
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#include <linux/backing-dev.h>
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#include <linux/mutex.h>
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#include <linux/rwsem.h>
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#include <linux/rbtree.h>
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#include <linux/poll.h>
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#include <linux/workqueue.h>
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#include <linux/kref.h>
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#include <linux/xattr.h>
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#include <linux/pid_namespace.h>
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#include <linux/refcount.h>
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#include <linux/user_namespace.h>
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/** Default max number of pages that can be used in a single read request */
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#define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32
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/** Maximum of max_pages received in init_out */
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#define FUSE_MAX_MAX_PAGES 256
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/** Bias for fi->writectr, meaning new writepages must not be sent */
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#define FUSE_NOWRITE INT_MIN
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/** It could be as large as PATH_MAX, but would that have any uses? */
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#define FUSE_NAME_MAX 1024
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/** Number of dentries for each connection in the control filesystem */
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#define FUSE_CTL_NUM_DENTRIES 5
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/** Number of page pointers embedded in fuse_req */
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#define FUSE_REQ_INLINE_PAGES 1
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/** List of active connections */
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extern struct list_head fuse_conn_list;
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/** Global mutex protecting fuse_conn_list and the control filesystem */
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extern struct mutex fuse_mutex;
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/** Module parameters */
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extern unsigned max_user_bgreq;
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extern unsigned max_user_congthresh;
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/* One forget request */
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struct fuse_forget_link {
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struct fuse_forget_one forget_one;
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struct fuse_forget_link *next;
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};
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/** FUSE inode */
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struct fuse_inode {
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/** Inode data */
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struct inode inode;
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/** Unique ID, which identifies the inode between userspace
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* and kernel */
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u64 nodeid;
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/** Number of lookups on this inode */
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u64 nlookup;
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/** The request used for sending the FORGET message */
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struct fuse_forget_link *forget;
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/** Time in jiffies until the file attributes are valid */
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u64 i_time;
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/* Which attributes are invalid */
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u32 inval_mask;
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/** The sticky bit in inode->i_mode may have been removed, so
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preserve the original mode */
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umode_t orig_i_mode;
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/** 64 bit inode number */
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u64 orig_ino;
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/** Version of last attribute change */
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u64 attr_version;
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union {
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/* Write related fields (regular file only) */
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struct {
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/* Files usable in writepage. Protected by fi->lock */
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struct list_head write_files;
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/* Writepages pending on truncate or fsync */
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struct list_head queued_writes;
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/* Number of sent writes, a negative bias
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* (FUSE_NOWRITE) means more writes are blocked */
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int writectr;
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/* Waitq for writepage completion */
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wait_queue_head_t page_waitq;
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/* List of writepage requestst (pending or sent) */
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struct list_head writepages;
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};
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/* readdir cache (directory only) */
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struct {
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/* true if fully cached */
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bool cached;
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/* size of cache */
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loff_t size;
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/* position at end of cache (position of next entry) */
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loff_t pos;
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/* version of the cache */
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u64 version;
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/* modification time of directory when cache was
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* started */
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struct timespec64 mtime;
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/* iversion of directory when cache was started */
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u64 iversion;
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/* protects above fields */
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spinlock_t lock;
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} rdc;
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};
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/** Miscellaneous bits describing inode state */
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unsigned long state;
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/** Lock for serializing lookup and readdir for back compatibility*/
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struct mutex mutex;
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/** Lock to protect write related fields */
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spinlock_t lock;
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};
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/** FUSE inode state bits */
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enum {
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/** Advise readdirplus */
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FUSE_I_ADVISE_RDPLUS,
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/** Initialized with readdirplus */
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FUSE_I_INIT_RDPLUS,
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/** An operation changing file size is in progress */
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FUSE_I_SIZE_UNSTABLE,
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};
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struct fuse_conn;
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/** FUSE specific file data */
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struct fuse_file {
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/** Fuse connection for this file */
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struct fuse_conn *fc;
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/*
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* Request reserved for flush and release.
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* Modified under relative fuse_inode::lock.
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*/
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struct fuse_req *reserved_req;
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/** Kernel file handle guaranteed to be unique */
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u64 kh;
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/** File handle used by userspace */
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u64 fh;
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/** Node id of this file */
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u64 nodeid;
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/** Refcount */
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refcount_t count;
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/** FOPEN_* flags returned by open */
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u32 open_flags;
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/** Entry on inode's write_files list */
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struct list_head write_entry;
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/* Readdir related */
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struct {
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/*
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* Protects below fields against (crazy) parallel readdir on
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* same open file. Uncontended in the normal case.
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*/
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struct mutex lock;
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/* Dir stream position */
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loff_t pos;
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/* Offset in cache */
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loff_t cache_off;
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/* Version of cache we are reading */
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u64 version;
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} readdir;
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/** RB node to be linked on fuse_conn->polled_files */
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struct rb_node polled_node;
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/** Wait queue head for poll */
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wait_queue_head_t poll_wait;
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/** Has flock been performed on this file? */
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bool flock:1;
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};
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/** One input argument of a request */
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struct fuse_in_arg {
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unsigned size;
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const void *value;
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};
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/** The request input */
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struct fuse_in {
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/** The request header */
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struct fuse_in_header h;
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/** True if the data for the last argument is in req->pages */
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unsigned argpages:1;
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/** Number of arguments */
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unsigned numargs;
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/** Array of arguments */
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struct fuse_in_arg args[3];
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};
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/** One output argument of a request */
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struct fuse_arg {
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unsigned size;
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void *value;
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};
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/** The request output */
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struct fuse_out {
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/** Header returned from userspace */
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struct fuse_out_header h;
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/*
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* The following bitfields are not changed during the request
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* processing
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*/
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/** Last argument is variable length (can be shorter than
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arg->size) */
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unsigned argvar:1;
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/** Last argument is a list of pages to copy data to */
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unsigned argpages:1;
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/** Zero partially or not copied pages */
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unsigned page_zeroing:1;
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/** Pages may be replaced with new ones */
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unsigned page_replace:1;
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/** Number or arguments */
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unsigned numargs;
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/** Array of arguments */
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struct fuse_arg args[2];
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};
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/** FUSE page descriptor */
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struct fuse_page_desc {
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unsigned int length;
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unsigned int offset;
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};
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struct fuse_args {
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struct {
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struct {
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uint32_t opcode;
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uint64_t nodeid;
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} h;
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unsigned numargs;
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struct fuse_in_arg args[3];
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} in;
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struct {
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unsigned argvar:1;
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unsigned numargs;
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struct fuse_arg args[2];
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} out;
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};
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#define FUSE_ARGS(args) struct fuse_args args = {}
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/** The request IO state (for asynchronous processing) */
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struct fuse_io_priv {
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struct kref refcnt;
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int async;
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spinlock_t lock;
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unsigned reqs;
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ssize_t bytes;
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size_t size;
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__u64 offset;
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bool write;
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bool should_dirty;
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int err;
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struct kiocb *iocb;
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struct completion *done;
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bool blocking;
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};
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#define FUSE_IO_PRIV_SYNC(i) \
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{ \
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.refcnt = KREF_INIT(1), \
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.async = 0, \
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.iocb = i, \
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}
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/**
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* Request flags
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*
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* FR_ISREPLY: set if the request has reply
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* FR_FORCE: force sending of the request even if interrupted
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* FR_BACKGROUND: request is sent in the background
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* FR_WAITING: request is counted as "waiting"
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* FR_ABORTED: the request was aborted
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* FR_INTERRUPTED: the request has been interrupted
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* FR_LOCKED: data is being copied to/from the request
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* FR_PENDING: request is not yet in userspace
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* FR_SENT: request is in userspace, waiting for an answer
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* FR_FINISHED: request is finished
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* FR_PRIVATE: request is on private list
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*/
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enum fuse_req_flag {
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FR_ISREPLY,
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FR_FORCE,
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FR_BACKGROUND,
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FR_WAITING,
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FR_ABORTED,
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FR_INTERRUPTED,
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FR_LOCKED,
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FR_PENDING,
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FR_SENT,
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FR_FINISHED,
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FR_PRIVATE,
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};
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/**
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* A request to the client
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*
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* .waitq.lock protects the following fields:
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* - FR_ABORTED
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* - FR_LOCKED (may also be modified under fc->lock, tested under both)
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*/
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struct fuse_req {
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/** This can be on either pending processing or io lists in
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fuse_conn */
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struct list_head list;
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/** Entry on the interrupts list */
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struct list_head intr_entry;
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/** refcount */
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refcount_t count;
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/* Request flags, updated with test/set/clear_bit() */
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unsigned long flags;
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/** The request input */
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struct fuse_in in;
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/** The request output */
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struct fuse_out out;
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/** Used to wake up the task waiting for completion of request*/
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wait_queue_head_t waitq;
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/** Data for asynchronous requests */
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union {
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struct {
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struct fuse_release_in in;
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struct inode *inode;
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} release;
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struct fuse_init_in init_in;
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struct fuse_init_out init_out;
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struct cuse_init_in cuse_init_in;
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struct {
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struct fuse_read_in in;
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u64 attr_ver;
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} read;
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struct {
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struct fuse_write_in in;
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struct fuse_write_out out;
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struct fuse_req *next;
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} write;
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struct fuse_notify_retrieve_in retrieve_in;
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} misc;
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/** page vector */
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struct page **pages;
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/** page-descriptor vector */
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struct fuse_page_desc *page_descs;
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/** size of the 'pages' array */
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unsigned max_pages;
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/** inline page vector */
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struct page *inline_pages[FUSE_REQ_INLINE_PAGES];
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/** inline page-descriptor vector */
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struct fuse_page_desc inline_page_descs[FUSE_REQ_INLINE_PAGES];
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/** number of pages in vector */
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unsigned num_pages;
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/** File used in the request (or NULL) */
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struct fuse_file *ff;
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/** Inode used in the request or NULL */
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struct inode *inode;
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/** AIO control block */
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struct fuse_io_priv *io;
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/** Link on fi->writepages */
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struct list_head writepages_entry;
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/** Request completion callback */
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void (*end)(struct fuse_conn *, struct fuse_req *);
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/** Request is stolen from fuse_file->reserved_req */
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struct file *stolen_file;
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};
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struct fuse_iqueue {
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/** Connection established */
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unsigned connected;
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/** Readers of the connection are waiting on this */
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wait_queue_head_t waitq;
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/** The next unique request id */
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u64 reqctr;
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/** The list of pending requests */
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struct list_head pending;
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/** Pending interrupts */
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struct list_head interrupts;
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/** Queue of pending forgets */
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struct fuse_forget_link forget_list_head;
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struct fuse_forget_link *forget_list_tail;
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/** Batching of FORGET requests (positive indicates FORGET batch) */
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int forget_batch;
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/** O_ASYNC requests */
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struct fasync_struct *fasync;
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};
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#define FUSE_PQ_HASH_BITS 8
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#define FUSE_PQ_HASH_SIZE (1 << FUSE_PQ_HASH_BITS)
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struct fuse_pqueue {
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/** Connection established */
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unsigned connected;
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/** Lock protecting accessess to members of this structure */
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spinlock_t lock;
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/** Hash table of requests being processed */
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struct list_head *processing;
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/** The list of requests under I/O */
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struct list_head io;
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};
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/**
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* Fuse device instance
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*/
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struct fuse_dev {
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/** Fuse connection for this device */
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struct fuse_conn *fc;
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/** Processing queue */
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struct fuse_pqueue pq;
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/** list entry on fc->devices */
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struct list_head entry;
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};
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/**
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* A Fuse connection.
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*
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* This structure is created, when the filesystem is mounted, and is
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* destroyed, when the client device is closed and the filesystem is
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* unmounted.
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*/
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struct fuse_conn {
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/** Lock protecting accessess to members of this structure */
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spinlock_t lock;
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/** Refcount */
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refcount_t count;
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/** Number of fuse_dev's */
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atomic_t dev_count;
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struct rcu_head rcu;
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/** The user id for this mount */
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kuid_t user_id;
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/** The group id for this mount */
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kgid_t group_id;
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/** The pid namespace for this mount */
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struct pid_namespace *pid_ns;
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/** The user namespace for this mount */
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struct user_namespace *user_ns;
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/** Maximum read size */
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unsigned max_read;
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/** Maximum write size */
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unsigned max_write;
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/** Maxmum number of pages that can be used in a single request */
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unsigned int max_pages;
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/** Input queue */
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struct fuse_iqueue iq;
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/** The next unique kernel file handle */
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atomic64_t khctr;
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/** rbtree of fuse_files waiting for poll events indexed by ph */
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struct rb_root polled_files;
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/** Maximum number of outstanding background requests */
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unsigned max_background;
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/** Number of background requests at which congestion starts */
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unsigned congestion_threshold;
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/** Number of requests currently in the background */
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unsigned num_background;
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/** Number of background requests currently queued for userspace */
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unsigned active_background;
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/** The list of background requests set aside for later queuing */
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struct list_head bg_queue;
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|
|
/** Protects: max_background, congestion_threshold, num_background,
|
|
* active_background, bg_queue, blocked */
|
|
spinlock_t bg_lock;
|
|
|
|
/** Flag indicating that INIT reply has been received. Allocating
|
|
* any fuse request will be suspended until the flag is set */
|
|
int initialized;
|
|
|
|
/** Flag indicating if connection is blocked. This will be
|
|
the case before the INIT reply is received, and if there
|
|
are too many outstading backgrounds requests */
|
|
int blocked;
|
|
|
|
/** waitq for blocked connection */
|
|
wait_queue_head_t blocked_waitq;
|
|
|
|
/** waitq for reserved requests */
|
|
wait_queue_head_t reserved_req_waitq;
|
|
|
|
/** Connection established, cleared on umount, connection
|
|
abort and device release */
|
|
unsigned connected;
|
|
|
|
/** Connection aborted via sysfs */
|
|
bool aborted;
|
|
|
|
/** Connection failed (version mismatch). Cannot race with
|
|
setting other bitfields since it is only set once in INIT
|
|
reply, before any other request, and never cleared */
|
|
unsigned conn_error:1;
|
|
|
|
/** Connection successful. Only set in INIT */
|
|
unsigned conn_init:1;
|
|
|
|
/** Do readpages asynchronously? Only set in INIT */
|
|
unsigned async_read:1;
|
|
|
|
/** Return an unique read error after abort. Only set in INIT */
|
|
unsigned abort_err:1;
|
|
|
|
/** Do not send separate SETATTR request before open(O_TRUNC) */
|
|
unsigned atomic_o_trunc:1;
|
|
|
|
/** Filesystem supports NFS exporting. Only set in INIT */
|
|
unsigned export_support:1;
|
|
|
|
/** write-back cache policy (default is write-through) */
|
|
unsigned writeback_cache:1;
|
|
|
|
/** allow parallel lookups and readdir (default is serialized) */
|
|
unsigned parallel_dirops:1;
|
|
|
|
/** handle fs handles killing suid/sgid/cap on write/chown/trunc */
|
|
unsigned handle_killpriv:1;
|
|
|
|
/** cache READLINK responses in page cache */
|
|
unsigned cache_symlinks:1;
|
|
|
|
/*
|
|
* The following bitfields are only for optimization purposes
|
|
* and hence races in setting them will not cause malfunction
|
|
*/
|
|
|
|
/** Is open/release not implemented by fs? */
|
|
unsigned no_open:1;
|
|
|
|
/** Is opendir/releasedir not implemented by fs? */
|
|
unsigned no_opendir:1;
|
|
|
|
/** Is fsync not implemented by fs? */
|
|
unsigned no_fsync:1;
|
|
|
|
/** Is fsyncdir not implemented by fs? */
|
|
unsigned no_fsyncdir:1;
|
|
|
|
/** Is flush not implemented by fs? */
|
|
unsigned no_flush:1;
|
|
|
|
/** Is setxattr not implemented by fs? */
|
|
unsigned no_setxattr:1;
|
|
|
|
/** Is getxattr not implemented by fs? */
|
|
unsigned no_getxattr:1;
|
|
|
|
/** Is listxattr not implemented by fs? */
|
|
unsigned no_listxattr:1;
|
|
|
|
/** Is removexattr not implemented by fs? */
|
|
unsigned no_removexattr:1;
|
|
|
|
/** Are posix file locking primitives not implemented by fs? */
|
|
unsigned no_lock:1;
|
|
|
|
/** Is access not implemented by fs? */
|
|
unsigned no_access:1;
|
|
|
|
/** Is create not implemented by fs? */
|
|
unsigned no_create:1;
|
|
|
|
/** Is interrupt not implemented by fs? */
|
|
unsigned no_interrupt:1;
|
|
|
|
/** Is bmap not implemented by fs? */
|
|
unsigned no_bmap:1;
|
|
|
|
/** Is poll not implemented by fs? */
|
|
unsigned no_poll:1;
|
|
|
|
/** Do multi-page cached writes */
|
|
unsigned big_writes:1;
|
|
|
|
/** Don't apply umask to creation modes */
|
|
unsigned dont_mask:1;
|
|
|
|
/** Are BSD file locking primitives not implemented by fs? */
|
|
unsigned no_flock:1;
|
|
|
|
/** Is fallocate not implemented by fs? */
|
|
unsigned no_fallocate:1;
|
|
|
|
/** Is rename with flags implemented by fs? */
|
|
unsigned no_rename2:1;
|
|
|
|
/** Use enhanced/automatic page cache invalidation. */
|
|
unsigned auto_inval_data:1;
|
|
|
|
/** Filesystem is fully reponsible for page cache invalidation. */
|
|
unsigned explicit_inval_data:1;
|
|
|
|
/** Does the filesystem support readdirplus? */
|
|
unsigned do_readdirplus:1;
|
|
|
|
/** Does the filesystem want adaptive readdirplus? */
|
|
unsigned readdirplus_auto:1;
|
|
|
|
/** Does the filesystem support asynchronous direct-IO submission? */
|
|
unsigned async_dio:1;
|
|
|
|
/** Is lseek not implemented by fs? */
|
|
unsigned no_lseek:1;
|
|
|
|
/** Does the filesystem support posix acls? */
|
|
unsigned posix_acl:1;
|
|
|
|
/** Check permissions based on the file mode or not? */
|
|
unsigned default_permissions:1;
|
|
|
|
/** Allow other than the mounter user to access the filesystem ? */
|
|
unsigned allow_other:1;
|
|
|
|
/** Does the filesystem support copy_file_range? */
|
|
unsigned no_copy_file_range:1;
|
|
|
|
/** The number of requests waiting for completion */
|
|
atomic_t num_waiting;
|
|
|
|
/** Negotiated minor version */
|
|
unsigned minor;
|
|
|
|
/** Entry on the fuse_conn_list */
|
|
struct list_head entry;
|
|
|
|
/** Device ID from super block */
|
|
dev_t dev;
|
|
|
|
/** Dentries in the control filesystem */
|
|
struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];
|
|
|
|
/** number of dentries used in the above array */
|
|
int ctl_ndents;
|
|
|
|
/** Key for lock owner ID scrambling */
|
|
u32 scramble_key[4];
|
|
|
|
/** Reserved request for the DESTROY message */
|
|
struct fuse_req *destroy_req;
|
|
|
|
/** Version counter for attribute changes */
|
|
atomic64_t attr_version;
|
|
|
|
/** Called on final put */
|
|
void (*release)(struct fuse_conn *);
|
|
|
|
/** Super block for this connection. */
|
|
struct super_block *sb;
|
|
|
|
/** Read/write semaphore to hold when accessing sb. */
|
|
struct rw_semaphore killsb;
|
|
|
|
/** List of device instances belonging to this connection */
|
|
struct list_head devices;
|
|
};
|
|
|
|
static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
|
|
{
|
|
return sb->s_fs_info;
|
|
}
|
|
|
|
static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
|
|
{
|
|
return get_fuse_conn_super(inode->i_sb);
|
|
}
|
|
|
|
static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
|
|
{
|
|
return container_of(inode, struct fuse_inode, inode);
|
|
}
|
|
|
|
static inline u64 get_node_id(struct inode *inode)
|
|
{
|
|
return get_fuse_inode(inode)->nodeid;
|
|
}
|
|
|
|
static inline int invalid_nodeid(u64 nodeid)
|
|
{
|
|
return !nodeid || nodeid == FUSE_ROOT_ID;
|
|
}
|
|
|
|
static inline u64 fuse_get_attr_version(struct fuse_conn *fc)
|
|
{
|
|
return atomic64_read(&fc->attr_version);
|
|
}
|
|
|
|
/** Device operations */
|
|
extern const struct file_operations fuse_dev_operations;
|
|
|
|
extern const struct dentry_operations fuse_dentry_operations;
|
|
extern const struct dentry_operations fuse_root_dentry_operations;
|
|
|
|
/**
|
|
* Inode to nodeid comparison.
|
|
*/
|
|
int fuse_inode_eq(struct inode *inode, void *_nodeidp);
|
|
|
|
/**
|
|
* Get a filled in inode
|
|
*/
|
|
struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
|
|
int generation, struct fuse_attr *attr,
|
|
u64 attr_valid, u64 attr_version);
|
|
|
|
int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name,
|
|
struct fuse_entry_out *outarg, struct inode **inode);
|
|
|
|
/**
|
|
* Send FORGET command
|
|
*/
|
|
void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
|
|
u64 nodeid, u64 nlookup);
|
|
|
|
struct fuse_forget_link *fuse_alloc_forget(void);
|
|
|
|
/* Used by READDIRPLUS */
|
|
void fuse_force_forget(struct file *file, u64 nodeid);
|
|
|
|
/**
|
|
* Initialize READ or READDIR request
|
|
*/
|
|
void fuse_read_fill(struct fuse_req *req, struct file *file,
|
|
loff_t pos, size_t count, int opcode);
|
|
|
|
/**
|
|
* Send OPEN or OPENDIR request
|
|
*/
|
|
int fuse_open_common(struct inode *inode, struct file *file, bool isdir);
|
|
|
|
struct fuse_file *fuse_file_alloc(struct fuse_conn *fc);
|
|
void fuse_file_free(struct fuse_file *ff);
|
|
void fuse_finish_open(struct inode *inode, struct file *file);
|
|
|
|
void fuse_sync_release(struct fuse_inode *fi, struct fuse_file *ff, int flags);
|
|
|
|
/**
|
|
* Send RELEASE or RELEASEDIR request
|
|
*/
|
|
void fuse_release_common(struct file *file, bool isdir);
|
|
|
|
/**
|
|
* Send FSYNC or FSYNCDIR request
|
|
*/
|
|
int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
|
|
int datasync, int opcode);
|
|
|
|
/**
|
|
* Notify poll wakeup
|
|
*/
|
|
int fuse_notify_poll_wakeup(struct fuse_conn *fc,
|
|
struct fuse_notify_poll_wakeup_out *outarg);
|
|
|
|
/**
|
|
* Initialize file operations on a regular file
|
|
*/
|
|
void fuse_init_file_inode(struct inode *inode);
|
|
|
|
/**
|
|
* Initialize inode operations on regular files and special files
|
|
*/
|
|
void fuse_init_common(struct inode *inode);
|
|
|
|
/**
|
|
* Initialize inode and file operations on a directory
|
|
*/
|
|
void fuse_init_dir(struct inode *inode);
|
|
|
|
/**
|
|
* Initialize inode operations on a symlink
|
|
*/
|
|
void fuse_init_symlink(struct inode *inode);
|
|
|
|
/**
|
|
* Change attributes of an inode
|
|
*/
|
|
void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
|
|
u64 attr_valid, u64 attr_version);
|
|
|
|
void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
|
|
u64 attr_valid);
|
|
|
|
/**
|
|
* Initialize the client device
|
|
*/
|
|
int fuse_dev_init(void);
|
|
|
|
/**
|
|
* Cleanup the client device
|
|
*/
|
|
void fuse_dev_cleanup(void);
|
|
|
|
int fuse_ctl_init(void);
|
|
void __exit fuse_ctl_cleanup(void);
|
|
|
|
/**
|
|
* Allocate a request
|
|
*/
|
|
struct fuse_req *fuse_request_alloc(unsigned npages);
|
|
|
|
struct fuse_req *fuse_request_alloc_nofs(unsigned npages);
|
|
|
|
bool fuse_req_realloc_pages(struct fuse_conn *fc, struct fuse_req *req,
|
|
gfp_t flags);
|
|
|
|
|
|
/**
|
|
* Free a request
|
|
*/
|
|
void fuse_request_free(struct fuse_req *req);
|
|
|
|
/**
|
|
* Get a request, may fail with -ENOMEM,
|
|
* caller should specify # elements in req->pages[] explicitly
|
|
*/
|
|
struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages);
|
|
struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
|
|
unsigned npages);
|
|
|
|
/*
|
|
* Increment reference count on request
|
|
*/
|
|
void __fuse_get_request(struct fuse_req *req);
|
|
|
|
/**
|
|
* Gets a requests for a file operation, always succeeds
|
|
*/
|
|
struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
|
|
struct file *file);
|
|
|
|
/**
|
|
* Decrement reference count of a request. If count goes to zero free
|
|
* the request.
|
|
*/
|
|
void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);
|
|
|
|
/**
|
|
* Send a request (synchronous)
|
|
*/
|
|
void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req);
|
|
|
|
/**
|
|
* Simple request sending that does request allocation and freeing
|
|
*/
|
|
ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args);
|
|
|
|
/**
|
|
* Send a request in the background
|
|
*/
|
|
void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req);
|
|
bool fuse_request_queue_background(struct fuse_conn *fc, struct fuse_req *req);
|
|
|
|
/* Abort all requests */
|
|
void fuse_abort_conn(struct fuse_conn *fc);
|
|
void fuse_wait_aborted(struct fuse_conn *fc);
|
|
|
|
/**
|
|
* Invalidate inode attributes
|
|
*/
|
|
void fuse_invalidate_attr(struct inode *inode);
|
|
|
|
void fuse_invalidate_entry_cache(struct dentry *entry);
|
|
|
|
void fuse_invalidate_atime(struct inode *inode);
|
|
|
|
u64 entry_attr_timeout(struct fuse_entry_out *o);
|
|
void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o);
|
|
|
|
/**
|
|
* Acquire reference to fuse_conn
|
|
*/
|
|
struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
|
|
|
|
/**
|
|
* Initialize fuse_conn
|
|
*/
|
|
void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns);
|
|
|
|
/**
|
|
* Release reference to fuse_conn
|
|
*/
|
|
void fuse_conn_put(struct fuse_conn *fc);
|
|
|
|
struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc);
|
|
void fuse_dev_free(struct fuse_dev *fud);
|
|
|
|
/**
|
|
* Add connection to control filesystem
|
|
*/
|
|
int fuse_ctl_add_conn(struct fuse_conn *fc);
|
|
|
|
/**
|
|
* Remove connection from control filesystem
|
|
*/
|
|
void fuse_ctl_remove_conn(struct fuse_conn *fc);
|
|
|
|
/**
|
|
* Is file type valid?
|
|
*/
|
|
int fuse_valid_type(int m);
|
|
|
|
/**
|
|
* Is current process allowed to perform filesystem operation?
|
|
*/
|
|
int fuse_allow_current_process(struct fuse_conn *fc);
|
|
|
|
u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
|
|
|
|
void fuse_update_ctime(struct inode *inode);
|
|
|
|
int fuse_update_attributes(struct inode *inode, struct file *file);
|
|
|
|
void fuse_flush_writepages(struct inode *inode);
|
|
|
|
void fuse_set_nowrite(struct inode *inode);
|
|
void fuse_release_nowrite(struct inode *inode);
|
|
|
|
/**
|
|
* File-system tells the kernel to invalidate cache for the given node id.
|
|
*/
|
|
int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
|
|
loff_t offset, loff_t len);
|
|
|
|
/**
|
|
* File-system tells the kernel to invalidate parent attributes and
|
|
* the dentry matching parent/name.
|
|
*
|
|
* If the child_nodeid is non-zero and:
|
|
* - matches the inode number for the dentry matching parent/name,
|
|
* - is not a mount point
|
|
* - is a file or oan empty directory
|
|
* then the dentry is unhashed (d_delete()).
|
|
*/
|
|
int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
|
|
u64 child_nodeid, struct qstr *name);
|
|
|
|
int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
|
|
bool isdir);
|
|
|
|
/**
|
|
* fuse_direct_io() flags
|
|
*/
|
|
|
|
/** If set, it is WRITE; otherwise - READ */
|
|
#define FUSE_DIO_WRITE (1 << 0)
|
|
|
|
/** CUSE pass fuse_direct_io() a file which f_mapping->host is not from FUSE */
|
|
#define FUSE_DIO_CUSE (1 << 1)
|
|
|
|
ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
|
|
loff_t *ppos, int flags);
|
|
long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
|
|
unsigned int flags);
|
|
long fuse_ioctl_common(struct file *file, unsigned int cmd,
|
|
unsigned long arg, unsigned int flags);
|
|
__poll_t fuse_file_poll(struct file *file, poll_table *wait);
|
|
int fuse_dev_release(struct inode *inode, struct file *file);
|
|
|
|
bool fuse_write_update_size(struct inode *inode, loff_t pos);
|
|
|
|
int fuse_flush_times(struct inode *inode, struct fuse_file *ff);
|
|
int fuse_write_inode(struct inode *inode, struct writeback_control *wbc);
|
|
|
|
int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
|
|
struct file *file);
|
|
|
|
void fuse_set_initialized(struct fuse_conn *fc);
|
|
|
|
void fuse_unlock_inode(struct inode *inode, bool locked);
|
|
bool fuse_lock_inode(struct inode *inode);
|
|
|
|
int fuse_setxattr(struct inode *inode, const char *name, const void *value,
|
|
size_t size, int flags);
|
|
ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value,
|
|
size_t size);
|
|
ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size);
|
|
int fuse_removexattr(struct inode *inode, const char *name);
|
|
extern const struct xattr_handler *fuse_xattr_handlers[];
|
|
extern const struct xattr_handler *fuse_acl_xattr_handlers[];
|
|
extern const struct xattr_handler *fuse_no_acl_xattr_handlers[];
|
|
|
|
struct posix_acl;
|
|
struct posix_acl *fuse_get_acl(struct inode *inode, int type);
|
|
int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type);
|
|
|
|
|
|
/* readdir.c */
|
|
int fuse_readdir(struct file *file, struct dir_context *ctx);
|
|
|
|
#endif /* _FS_FUSE_I_H */
|