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![Vivek Goyal](/assets/img/avatar_default.png)
commit4f06dd92b5
upstream. There are two modes for write(2) and friends in fuse: a) write through (update page cache, send sync WRITE request to userspace) b) buffered write (update page cache, async writeout later) The write through method kept all the page cache pages locked that were used for the request. Keeping more than one page locked is deadlock prone and Qian Cai demonstrated this with trinity fuzzing. The reason for keeping the pages locked is that concurrent mapped reads shouldn't try to pull possibly stale data into the page cache. For full page writes, the easy way to fix this is to make the cached page be the authoritative source by marking the page PG_uptodate immediately. After this the page can be safely unlocked, since mapped/cached reads will take the written data from the cache. Concurrent mapped writes will now cause data in the original WRITE request to be updated; this however doesn't cause any data inconsistency and this scenario should be exceedingly rare anyway. If the WRITE request returns with an error in the above case, currently the page is not marked uptodate; this means that a concurrent read will always read consistent data. After this patch the page is uptodate between writing to the cache and receiving the error: there's window where a cached read will read the wrong data. While theoretically this could be a regression, it is unlikely to be one in practice, since this is normal for buffered writes. In case of a partial page write to an already uptodate page the locking is also unnecessary, with the above caveats. Partial write of a not uptodate page still needs to be handled. One way would be to read the complete page before doing the write. This is not possible, since it might break filesystems that don't expect any READ requests when the file was opened O_WRONLY. The other solution is to serialize the synchronous write with reads from the partial pages. The easiest way to do this is to keep the partial pages locked. The problem is that a write() may involve two such pages (one head and one tail). This patch fixes it by only locking the partial tail page. If there's a partial head page as well, then split that off as a separate WRITE request. Reported-by: Qian Cai <cai@lca.pw> Link: https://lore.kernel.org/linux-fsdevel/4794a3fa3742a5e84fb0f934944204b55730829b.camel@lca.pw/ Fixes:ea9b9907b8
("fuse: implement perform_write") Cc: <stable@vger.kernel.org> # v2.6.26 Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1110 lines
26 KiB
C
1110 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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/** 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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/* Bad inode */
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FUSE_I_BAD,
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};
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struct fuse_conn;
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struct fuse_release_args;
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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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/* Argument space reserved for release */
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struct fuse_release_args *release_args;
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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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/** 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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/** 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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uint64_t nodeid;
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uint32_t opcode;
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unsigned short in_numargs;
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unsigned short out_numargs;
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bool force:1;
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bool noreply:1;
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bool nocreds:1;
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bool in_pages:1;
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bool out_pages:1;
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bool out_argvar:1;
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bool page_zeroing:1;
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bool page_replace:1;
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bool may_block:1;
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struct fuse_in_arg in_args[3];
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struct fuse_arg out_args[2];
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void (*end)(struct fuse_conn *fc, struct fuse_args *args, int error);
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};
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struct fuse_args_pages {
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struct fuse_args args;
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struct page **pages;
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struct fuse_page_desc *descs;
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unsigned int num_pages;
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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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* FR_ASYNC: request is asynchronous
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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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FR_ASYNC,
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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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/* Input/output arguments */
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struct fuse_args *args;
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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 header */
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struct {
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struct fuse_in_header h;
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} in;
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/* The request output header */
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struct {
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struct fuse_out_header h;
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} 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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#if IS_ENABLED(CONFIG_VIRTIO_FS)
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/** virtio-fs's physically contiguous buffer for in and out args */
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void *argbuf;
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#endif
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};
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struct fuse_iqueue;
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/**
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* Input queue callbacks
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*
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* Input queue signalling is device-specific. For example, the /dev/fuse file
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* uses fiq->waitq and fasync to wake processes that are waiting on queue
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* readiness. These callbacks allow other device types to respond to input
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* queue activity.
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*/
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struct fuse_iqueue_ops {
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/**
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* Signal that a forget has been queued
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*/
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void (*wake_forget_and_unlock)(struct fuse_iqueue *fiq)
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__releases(fiq->lock);
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/**
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* Signal that an INTERRUPT request has been queued
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*/
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void (*wake_interrupt_and_unlock)(struct fuse_iqueue *fiq)
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__releases(fiq->lock);
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/**
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* Signal that a request has been queued
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*/
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void (*wake_pending_and_unlock)(struct fuse_iqueue *fiq)
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__releases(fiq->lock);
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/**
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* Clean up when fuse_iqueue is destroyed
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*/
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void (*release)(struct fuse_iqueue *fiq);
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};
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/** /dev/fuse input queue operations */
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extern const struct fuse_iqueue_ops fuse_dev_fiq_ops;
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struct fuse_iqueue {
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/** Connection established */
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unsigned connected;
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/** Lock protecting accesses to members of this structure */
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spinlock_t lock;
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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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/** Device-specific callbacks */
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const struct fuse_iqueue_ops *ops;
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/** Device-specific state */
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void *priv;
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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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struct fuse_fs_context {
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int fd;
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unsigned int rootmode;
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kuid_t user_id;
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kgid_t group_id;
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bool is_bdev:1;
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bool fd_present:1;
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bool rootmode_present:1;
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bool user_id_present:1;
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bool group_id_present:1;
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bool default_permissions:1;
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bool allow_other:1;
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bool destroy:1;
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bool no_control:1;
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bool no_force_umount:1;
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bool no_mount_options:1;
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unsigned int max_read;
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unsigned int blksize;
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const char *subtype;
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/* fuse_dev pointer to fill in, should contain NULL on entry */
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void **fudptr;
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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;
|
|
|
|
/** The list of background requests set aside for later queuing */
|
|
struct list_head bg_queue;
|
|
|
|
/** 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;
|
|
|
|
/** 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;
|
|
|
|
/* Send DESTROY request */
|
|
unsigned int destroy:1;
|
|
|
|
/* Delete dentries that have gone stale */
|
|
unsigned int delete_stale:1;
|
|
|
|
/** Do not create entry in fusectl fs */
|
|
unsigned int no_control:1;
|
|
|
|
/** Do not allow MNT_FORCE umount */
|
|
unsigned int no_force_umount:1;
|
|
|
|
/* Do not show mount options */
|
|
unsigned int no_mount_options: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];
|
|
|
|
/** 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);
|
|
}
|
|
|
|
static inline void fuse_make_bad(struct inode *inode)
|
|
{
|
|
remove_inode_hash(inode);
|
|
set_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state);
|
|
}
|
|
|
|
static inline bool fuse_is_bad(struct inode *inode)
|
|
{
|
|
return unlikely(test_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state));
|
|
}
|
|
|
|
/** 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);
|
|
|
|
struct fuse_forget_link *fuse_dequeue_forget(struct fuse_iqueue *fiq,
|
|
unsigned int max,
|
|
unsigned int *countp);
|
|
|
|
/*
|
|
* Initialize READ or READDIR request
|
|
*/
|
|
struct fuse_io_args {
|
|
union {
|
|
struct {
|
|
struct fuse_read_in in;
|
|
u64 attr_ver;
|
|
} read;
|
|
struct {
|
|
struct fuse_write_in in;
|
|
struct fuse_write_out out;
|
|
bool page_locked;
|
|
} write;
|
|
};
|
|
struct fuse_args_pages ap;
|
|
struct fuse_io_priv *io;
|
|
struct fuse_file *ff;
|
|
};
|
|
|
|
void fuse_read_args_fill(struct fuse_io_args *ia, 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);
|
|
|
|
/**
|
|
* Simple request sending that does request allocation and freeing
|
|
*/
|
|
ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args);
|
|
int fuse_simple_background(struct fuse_conn *fc, struct fuse_args *args,
|
|
gfp_t gfp_flags);
|
|
|
|
/**
|
|
* End a finished request
|
|
*/
|
|
void fuse_request_end(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,
|
|
const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv);
|
|
|
|
/**
|
|
* Release reference to fuse_conn
|
|
*/
|
|
void fuse_conn_put(struct fuse_conn *fc);
|
|
|
|
struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc);
|
|
struct fuse_dev *fuse_dev_alloc(void);
|
|
void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc);
|
|
void fuse_dev_free(struct fuse_dev *fud);
|
|
void fuse_send_init(struct fuse_conn *fc);
|
|
|
|
/**
|
|
* Fill in superblock and initialize fuse connection
|
|
* @sb: partially-initialized superblock to fill in
|
|
* @ctx: mount context
|
|
*/
|
|
int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx);
|
|
|
|
/**
|
|
* Disassociate fuse connection from superblock and kill the superblock
|
|
*
|
|
* Calls kill_anon_super(), do not use with bdev mounts.
|
|
*/
|
|
void fuse_kill_sb_anon(struct super_block *sb);
|
|
|
|
/**
|
|
* 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);
|
|
|
|
bool fuse_invalid_attr(struct fuse_attr *attr);
|
|
|
|
/**
|
|
* 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);
|
|
|
|
/**
|
|
* Return the number of bytes in an arguments list
|
|
*/
|
|
unsigned int fuse_len_args(unsigned int numargs, struct fuse_arg *args);
|
|
|
|
/**
|
|
* Get the next unique ID for a request
|
|
*/
|
|
u64 fuse_get_unique(struct fuse_iqueue *fiq);
|
|
void fuse_free_conn(struct fuse_conn *fc);
|
|
|
|
#endif /* _FS_FUSE_I_H */
|