inode.c 30.0 KB
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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.
  See the file COPYING.
*/

#include "fuse_i.h"

#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/file.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/parser.h>
#include <linux/statfs.h>
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#include <linux/random.h>
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#include <linux/sched.h>
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#include <linux/exportfs.h>
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MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
MODULE_DESCRIPTION("Filesystem in Userspace");
MODULE_LICENSE("GPL");

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static struct kmem_cache *fuse_inode_cachep;
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struct list_head fuse_conn_list;
DEFINE_MUTEX(fuse_mutex);
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static int set_global_limit(const char *val, struct kernel_param *kp);

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unsigned max_user_bgreq;
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module_param_call(max_user_bgreq, set_global_limit, param_get_uint,
		  &max_user_bgreq, 0644);
__MODULE_PARM_TYPE(max_user_bgreq, "uint");
MODULE_PARM_DESC(max_user_bgreq,
 "Global limit for the maximum number of backgrounded requests an "
 "unprivileged user can set");

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unsigned max_user_congthresh;
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module_param_call(max_user_congthresh, set_global_limit, param_get_uint,
		  &max_user_congthresh, 0644);
__MODULE_PARM_TYPE(max_user_congthresh, "uint");
MODULE_PARM_DESC(max_user_congthresh,
 "Global limit for the maximum congestion threshold an "
 "unprivileged user can set");

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#define FUSE_SUPER_MAGIC 0x65735546

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#define FUSE_DEFAULT_BLKSIZE 512

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/** Maximum number of outstanding background requests */
#define FUSE_DEFAULT_MAX_BACKGROUND 12

/** Congestion starts at 75% of maximum */
#define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4)

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struct fuse_mount_data {
	int fd;
	unsigned rootmode;
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	kuid_t user_id;
	kgid_t group_id;
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	unsigned fd_present:1;
	unsigned rootmode_present:1;
	unsigned user_id_present:1;
	unsigned group_id_present:1;
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	unsigned flags;
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	unsigned max_read;
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	unsigned blksize;
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};

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struct fuse_forget_link *fuse_alloc_forget(void)
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{
	return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL);
}

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static struct inode *fuse_alloc_inode(struct super_block *sb)
{
	struct inode *inode;
	struct fuse_inode *fi;

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	inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
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	if (!inode)
		return NULL;

	fi = get_fuse_inode(inode);
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	fi->i_time = 0;
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	fi->nodeid = 0;
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	fi->nlookup = 0;
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	fi->attr_version = 0;
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	fi->writectr = 0;
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	fi->orig_ino = 0;
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	fi->state = 0;
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	INIT_LIST_HEAD(&fi->write_files);
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	INIT_LIST_HEAD(&fi->queued_writes);
	INIT_LIST_HEAD(&fi->writepages);
	init_waitqueue_head(&fi->page_waitq);
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	fi->forget = fuse_alloc_forget();
	if (!fi->forget) {
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		kmem_cache_free(fuse_inode_cachep, inode);
		return NULL;
	}
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	return inode;
}

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static void fuse_i_callback(struct rcu_head *head)
{
	struct inode *inode = container_of(head, struct inode, i_rcu);
	kmem_cache_free(fuse_inode_cachep, inode);
}

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static void fuse_destroy_inode(struct inode *inode)
{
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	struct fuse_inode *fi = get_fuse_inode(inode);
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	BUG_ON(!list_empty(&fi->write_files));
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	BUG_ON(!list_empty(&fi->queued_writes));
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	kfree(fi->forget);
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	call_rcu(&inode->i_rcu, fuse_i_callback);
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}

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static void fuse_evict_inode(struct inode *inode)
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{
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	truncate_inode_pages(&inode->i_data, 0);
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	clear_inode(inode);
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	if (inode->i_sb->s_flags & MS_ACTIVE) {
		struct fuse_conn *fc = get_fuse_conn(inode);
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		struct fuse_inode *fi = get_fuse_inode(inode);
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		fuse_queue_forget(fc, fi->forget, fi->nodeid, fi->nlookup);
		fi->forget = NULL;
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	}
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}

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static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
{
	if (*flags & MS_MANDLOCK)
		return -EINVAL;

	return 0;
}

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/*
 * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
 * so that it will fit.
 */
static ino_t fuse_squash_ino(u64 ino64)
{
	ino_t ino = (ino_t) ino64;
	if (sizeof(ino_t) < sizeof(u64))
		ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8;
	return ino;
}

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void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
				   u64 attr_valid)
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{
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	struct fuse_conn *fc = get_fuse_conn(inode);
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	struct fuse_inode *fi = get_fuse_inode(inode);
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	fi->attr_version = ++fc->attr_version;
	fi->i_time = attr_valid;

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	inode->i_ino     = fuse_squash_ino(attr->ino);
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	inode->i_mode    = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
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	set_nlink(inode, attr->nlink);
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	inode->i_uid     = make_kuid(&init_user_ns, attr->uid);
	inode->i_gid     = make_kgid(&init_user_ns, attr->gid);
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	inode->i_blocks  = attr->blocks;
	inode->i_atime.tv_sec   = attr->atime;
	inode->i_atime.tv_nsec  = attr->atimensec;
	inode->i_mtime.tv_sec   = attr->mtime;
	inode->i_mtime.tv_nsec  = attr->mtimensec;
	inode->i_ctime.tv_sec   = attr->ctime;
	inode->i_ctime.tv_nsec  = attr->ctimensec;
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	if (attr->blksize != 0)
		inode->i_blkbits = ilog2(attr->blksize);
	else
		inode->i_blkbits = inode->i_sb->s_blocksize_bits;

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	/*
	 * Don't set the sticky bit in i_mode, unless we want the VFS
	 * to check permissions.  This prevents failures due to the
	 * check in may_delete().
	 */
	fi->orig_i_mode = inode->i_mode;
	if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
		inode->i_mode &= ~S_ISVTX;
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	fi->orig_ino = attr->ino;
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}

void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
			    u64 attr_valid, u64 attr_version)
{
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_inode *fi = get_fuse_inode(inode);
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	bool is_wb = fc->writeback_cache;
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	loff_t oldsize;
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	struct timespec old_mtime;
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	spin_lock(&fc->lock);
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	if ((attr_version != 0 && fi->attr_version > attr_version) ||
	    test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) {
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		spin_unlock(&fc->lock);
		return;
	}

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	old_mtime = inode->i_mtime;
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	fuse_change_attributes_common(inode, attr, attr_valid);
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	oldsize = inode->i_size;
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	/*
	 * In case of writeback_cache enabled, the cached writes beyond EOF
	 * extend local i_size without keeping userspace server in sync. So,
	 * attr->size coming from server can be stale. We cannot trust it.
	 */
	if (!is_wb || !S_ISREG(inode->i_mode))
		i_size_write(inode, attr->size);
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	spin_unlock(&fc->lock);

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	if (!is_wb && S_ISREG(inode->i_mode)) {
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		bool inval = false;

		if (oldsize != attr->size) {
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			truncate_pagecache(inode, attr->size);
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			inval = true;
		} else if (fc->auto_inval_data) {
			struct timespec new_mtime = {
				.tv_sec = attr->mtime,
				.tv_nsec = attr->mtimensec,
			};

			/*
			 * Auto inval mode also checks and invalidates if mtime
			 * has changed.
			 */
			if (!timespec_equal(&old_mtime, &new_mtime))
				inval = true;
		}

		if (inval)
			invalidate_inode_pages2(inode->i_mapping);
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	}
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}

static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
{
	inode->i_mode = attr->mode & S_IFMT;
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	inode->i_size = attr->size;
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	if (S_ISREG(inode->i_mode)) {
		fuse_init_common(inode);
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		fuse_init_file_inode(inode);
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	} else if (S_ISDIR(inode->i_mode))
		fuse_init_dir(inode);
	else if (S_ISLNK(inode->i_mode))
		fuse_init_symlink(inode);
	else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
		 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
		fuse_init_common(inode);
		init_special_inode(inode, inode->i_mode,
				   new_decode_dev(attr->rdev));
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	} else
		BUG();
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}

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int fuse_inode_eq(struct inode *inode, void *_nodeidp)
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{
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	u64 nodeid = *(u64 *) _nodeidp;
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	if (get_node_id(inode) == nodeid)
		return 1;
	else
		return 0;
}

static int fuse_inode_set(struct inode *inode, void *_nodeidp)
{
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	u64 nodeid = *(u64 *) _nodeidp;
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	get_fuse_inode(inode)->nodeid = nodeid;
	return 0;
}

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struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
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			int generation, struct fuse_attr *attr,
			u64 attr_valid, u64 attr_version)
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{
	struct inode *inode;
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	struct fuse_inode *fi;
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	struct fuse_conn *fc = get_fuse_conn_super(sb);

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	inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
	if (!inode)
		return NULL;

	if ((inode->i_state & I_NEW)) {
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		inode->i_flags |= S_NOATIME|S_NOCMTIME;
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		inode->i_generation = generation;
		inode->i_data.backing_dev_info = &fc->bdi;
		fuse_init_inode(inode, attr);
		unlock_new_inode(inode);
	} else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
		/* Inode has changed type, any I/O on the old should fail */
		make_bad_inode(inode);
		iput(inode);
		goto retry;
	}

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	fi = get_fuse_inode(inode);
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	spin_lock(&fc->lock);
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	fi->nlookup++;
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	spin_unlock(&fc->lock);
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	fuse_change_attributes(inode, attr, attr_valid, attr_version);

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	return inode;
}

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int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
			     loff_t offset, loff_t len)
{
	struct inode *inode;
	pgoff_t pg_start;
	pgoff_t pg_end;

	inode = ilookup5(sb, nodeid, fuse_inode_eq, &nodeid);
	if (!inode)
		return -ENOENT;

	fuse_invalidate_attr(inode);
	if (offset >= 0) {
		pg_start = offset >> PAGE_CACHE_SHIFT;
		if (len <= 0)
			pg_end = -1;
		else
			pg_end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
		invalidate_inode_pages2_range(inode->i_mapping,
					      pg_start, pg_end);
	}
	iput(inode);
	return 0;
}

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static void fuse_umount_begin(struct super_block *sb)
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{
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	fuse_abort_conn(get_fuse_conn_super(sb));
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}

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static void fuse_send_destroy(struct fuse_conn *fc)
{
	struct fuse_req *req = fc->destroy_req;
	if (req && fc->conn_init) {
		fc->destroy_req = NULL;
		req->in.h.opcode = FUSE_DESTROY;
		req->force = 1;
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		req->background = 0;
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		fuse_request_send(fc, req);
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		fuse_put_request(fc, req);
	}
}

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static void fuse_bdi_destroy(struct fuse_conn *fc)
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{
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	if (fc->bdi_initialized)
		bdi_destroy(&fc->bdi);
}
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void fuse_conn_kill(struct fuse_conn *fc)
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{
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	spin_lock(&fc->lock);
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	fc->connected = 0;
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	fc->blocked = 0;
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	fc->initialized = 1;
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	spin_unlock(&fc->lock);
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	/* Flush all readers on this fs */
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	kill_fasync(&fc->fasync, SIGIO, POLL_IN);
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	wake_up_all(&fc->waitq);
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	wake_up_all(&fc->blocked_waitq);
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	wake_up_all(&fc->reserved_req_waitq);
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}
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EXPORT_SYMBOL_GPL(fuse_conn_kill);
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static void fuse_put_super(struct super_block *sb)
{
	struct fuse_conn *fc = get_fuse_conn_super(sb);

	fuse_send_destroy(fc);
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	fuse_conn_kill(fc);
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	mutex_lock(&fuse_mutex);
	list_del(&fc->entry);
	fuse_ctl_remove_conn(fc);
	mutex_unlock(&fuse_mutex);
	fuse_bdi_destroy(fc);

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	fuse_conn_put(fc);
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}

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static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
{
	stbuf->f_type    = FUSE_SUPER_MAGIC;
	stbuf->f_bsize   = attr->bsize;
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	stbuf->f_frsize  = attr->frsize;
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	stbuf->f_blocks  = attr->blocks;
	stbuf->f_bfree   = attr->bfree;
	stbuf->f_bavail  = attr->bavail;
	stbuf->f_files   = attr->files;
	stbuf->f_ffree   = attr->ffree;
	stbuf->f_namelen = attr->namelen;
	/* fsid is left zero */
}

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static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
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{
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	struct super_block *sb = dentry->d_sb;
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	struct fuse_conn *fc = get_fuse_conn_super(sb);
	struct fuse_req *req;
	struct fuse_statfs_out outarg;
	int err;

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	if (!fuse_allow_current_process(fc)) {
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		buf->f_type = FUSE_SUPER_MAGIC;
		return 0;
	}

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	req = fuse_get_req_nopages(fc);
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	if (IS_ERR(req))
		return PTR_ERR(req);
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	memset(&outarg, 0, sizeof(outarg));
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	req->in.numargs = 0;
	req->in.h.opcode = FUSE_STATFS;
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	req->in.h.nodeid = get_node_id(dentry->d_inode);
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	req->out.numargs = 1;
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	req->out.args[0].size =
		fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
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	req->out.args[0].value = &outarg;
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	fuse_request_send(fc, req);
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	err = req->out.h.error;
	if (!err)
		convert_fuse_statfs(buf, &outarg.st);
	fuse_put_request(fc, req);
	return err;
}

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enum {
	OPT_FD,
	OPT_ROOTMODE,
	OPT_USER_ID,
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	OPT_GROUP_ID,
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	OPT_DEFAULT_PERMISSIONS,
	OPT_ALLOW_OTHER,
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	OPT_MAX_READ,
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	OPT_BLKSIZE,
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	OPT_ERR
};

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static const match_table_t tokens = {
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	{OPT_FD,			"fd=%u"},
	{OPT_ROOTMODE,			"rootmode=%o"},
	{OPT_USER_ID,			"user_id=%u"},
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	{OPT_GROUP_ID,			"group_id=%u"},
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	{OPT_DEFAULT_PERMISSIONS,	"default_permissions"},
	{OPT_ALLOW_OTHER,		"allow_other"},
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	{OPT_MAX_READ,			"max_read=%u"},
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	{OPT_BLKSIZE,			"blksize=%u"},
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	{OPT_ERR,			NULL}
};

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static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
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{
	char *p;
	memset(d, 0, sizeof(struct fuse_mount_data));
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	d->max_read = ~0;
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	d->blksize = FUSE_DEFAULT_BLKSIZE;
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	while ((p = strsep(&opt, ",")) != NULL) {
		int token;
		int value;
		substring_t args[MAX_OPT_ARGS];
		if (!*p)
			continue;

		token = match_token(p, tokens, args);
		switch (token) {
		case OPT_FD:
			if (match_int(&args[0], &value))
				return 0;
			d->fd = value;
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			d->fd_present = 1;
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			break;

		case OPT_ROOTMODE:
			if (match_octal(&args[0], &value))
				return 0;
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			if (!fuse_valid_type(value))
				return 0;
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			d->rootmode = value;
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			d->rootmode_present = 1;
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			break;

		case OPT_USER_ID:
			if (match_int(&args[0], &value))
				return 0;
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			d->user_id = make_kuid(current_user_ns(), value);
			if (!uid_valid(d->user_id))
				return 0;
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			d->user_id_present = 1;
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			break;

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		case OPT_GROUP_ID:
			if (match_int(&args[0], &value))
				return 0;
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			d->group_id = make_kgid(current_user_ns(), value);
			if (!gid_valid(d->group_id))
				return 0;
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			d->group_id_present = 1;
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			break;

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		case OPT_DEFAULT_PERMISSIONS:
			d->flags |= FUSE_DEFAULT_PERMISSIONS;
			break;

		case OPT_ALLOW_OTHER:
			d->flags |= FUSE_ALLOW_OTHER;
			break;

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		case OPT_MAX_READ:
			if (match_int(&args[0], &value))
				return 0;
			d->max_read = value;
			break;

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Miklos Szeredi 已提交
535 536 537 538 539 540
		case OPT_BLKSIZE:
			if (!is_bdev || match_int(&args[0], &value))
				return 0;
			d->blksize = value;
			break;

M
Miklos Szeredi 已提交
541 542 543 544
		default:
			return 0;
		}
	}
545 546 547

	if (!d->fd_present || !d->rootmode_present ||
	    !d->user_id_present || !d->group_id_present)
M
Miklos Szeredi 已提交
548 549 550 551 552
		return 0;

	return 1;
}

553
static int fuse_show_options(struct seq_file *m, struct dentry *root)
M
Miklos Szeredi 已提交
554
{
555 556
	struct super_block *sb = root->d_sb;
	struct fuse_conn *fc = get_fuse_conn_super(sb);
M
Miklos Szeredi 已提交
557

558 559
	seq_printf(m, ",user_id=%u", from_kuid_munged(&init_user_ns, fc->user_id));
	seq_printf(m, ",group_id=%u", from_kgid_munged(&init_user_ns, fc->group_id));
M
Miklos Szeredi 已提交
560 561 562 563
	if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
		seq_puts(m, ",default_permissions");
	if (fc->flags & FUSE_ALLOW_OTHER)
		seq_puts(m, ",allow_other");
564 565
	if (fc->max_read != ~0)
		seq_printf(m, ",max_read=%u", fc->max_read);
566 567
	if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
		seq_printf(m, ",blksize=%lu", sb->s_blocksize);
M
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568 569 570
	return 0;
}

571
void fuse_conn_init(struct fuse_conn *fc)
M
Miklos Szeredi 已提交
572
{
573 574
	memset(fc, 0, sizeof(*fc));
	spin_lock_init(&fc->lock);
J
John Muir 已提交
575
	init_rwsem(&fc->killsb);
576 577 578 579 580 581 582 583 584 585
	atomic_set(&fc->count, 1);
	init_waitqueue_head(&fc->waitq);
	init_waitqueue_head(&fc->blocked_waitq);
	init_waitqueue_head(&fc->reserved_req_waitq);
	INIT_LIST_HEAD(&fc->pending);
	INIT_LIST_HEAD(&fc->processing);
	INIT_LIST_HEAD(&fc->io);
	INIT_LIST_HEAD(&fc->interrupts);
	INIT_LIST_HEAD(&fc->bg_queue);
	INIT_LIST_HEAD(&fc->entry);
586
	fc->forget_list_tail = &fc->forget_list_head;
587
	atomic_set(&fc->num_waiting, 0);
588 589
	fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND;
	fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD;
590 591 592
	fc->khctr = 0;
	fc->polled_files = RB_ROOT;
	fc->reqctr = 0;
593
	fc->blocked = 0;
M
Maxim Patlasov 已提交
594
	fc->initialized = 0;
595 596
	fc->attr_version = 1;
	get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
M
Miklos Szeredi 已提交
597
}
598
EXPORT_SYMBOL_GPL(fuse_conn_init);
M
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599

600 601
void fuse_conn_put(struct fuse_conn *fc)
{
602
	if (atomic_dec_and_test(&fc->count)) {
603 604
		if (fc->destroy_req)
			fuse_request_free(fc->destroy_req);
T
Tejun Heo 已提交
605
		fc->release(fc);
606
	}
607
}
608
EXPORT_SYMBOL_GPL(fuse_conn_put);
609 610 611 612 613 614

struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
{
	atomic_inc(&fc->count);
	return fc;
}
615
EXPORT_SYMBOL_GPL(fuse_conn_get);
616

617
static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
M
Miklos Szeredi 已提交
618 619 620 621 622 623
{
	struct fuse_attr attr;
	memset(&attr, 0, sizeof(attr));

	attr.mode = mode;
	attr.ino = FUSE_ROOT_ID;
624
	attr.nlink = 1;
625
	return fuse_iget(sb, 1, 0, &attr, 0, 0);
M
Miklos Szeredi 已提交
626 627
}

M
Miklos Szeredi 已提交
628
struct fuse_inode_handle {
M
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629 630 631 632 633 634 635
	u64 nodeid;
	u32 generation;
};

static struct dentry *fuse_get_dentry(struct super_block *sb,
				      struct fuse_inode_handle *handle)
{
636
	struct fuse_conn *fc = get_fuse_conn_super(sb);
M
Miklos Szeredi 已提交
637 638 639 640 641 642 643 644
	struct inode *inode;
	struct dentry *entry;
	int err = -ESTALE;

	if (handle->nodeid == 0)
		goto out_err;

	inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid);
645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665
	if (!inode) {
		struct fuse_entry_out outarg;
		struct qstr name;

		if (!fc->export_support)
			goto out_err;

		name.len = 1;
		name.name = ".";
		err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg,
				       &inode);
		if (err && err != -ENOENT)
			goto out_err;
		if (err || !inode) {
			err = -ESTALE;
			goto out_err;
		}
		err = -EIO;
		if (get_node_id(inode) != handle->nodeid)
			goto out_iput;
	}
M
Miklos Szeredi 已提交
666 667 668 669
	err = -ESTALE;
	if (inode->i_generation != handle->generation)
		goto out_iput;

670
	entry = d_obtain_alias(inode);
A
Al Viro 已提交
671
	if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID)
M
Miklos Szeredi 已提交
672 673 674 675 676 677 678 679 680 681
		fuse_invalidate_entry_cache(entry);

	return entry;

 out_iput:
	iput(inode);
 out_err:
	return ERR_PTR(err);
}

A
Al Viro 已提交
682 683
static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len,
			   struct inode *parent)
M
Miklos Szeredi 已提交
684
{
A
Al Viro 已提交
685
	int len = parent ? 6 : 3;
M
Miklos Szeredi 已提交
686 687 688
	u64 nodeid;
	u32 generation;

689 690
	if (*max_len < len) {
		*max_len = len;
691
		return  FILEID_INVALID;
692
	}
M
Miklos Szeredi 已提交
693 694 695 696 697 698 699 700

	nodeid = get_fuse_inode(inode)->nodeid;
	generation = inode->i_generation;

	fh[0] = (u32)(nodeid >> 32);
	fh[1] = (u32)(nodeid & 0xffffffff);
	fh[2] = generation;

A
Al Viro 已提交
701
	if (parent) {
M
Miklos Szeredi 已提交
702 703 704 705 706 707 708 709 710
		nodeid = get_fuse_inode(parent)->nodeid;
		generation = parent->i_generation;

		fh[3] = (u32)(nodeid >> 32);
		fh[4] = (u32)(nodeid & 0xffffffff);
		fh[5] = generation;
	}

	*max_len = len;
A
Al Viro 已提交
711
	return parent ? 0x82 : 0x81;
M
Miklos Szeredi 已提交
712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741
}

static struct dentry *fuse_fh_to_dentry(struct super_block *sb,
		struct fid *fid, int fh_len, int fh_type)
{
	struct fuse_inode_handle handle;

	if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3)
		return NULL;

	handle.nodeid = (u64) fid->raw[0] << 32;
	handle.nodeid |= (u64) fid->raw[1];
	handle.generation = fid->raw[2];
	return fuse_get_dentry(sb, &handle);
}

static struct dentry *fuse_fh_to_parent(struct super_block *sb,
		struct fid *fid, int fh_len, int fh_type)
{
	struct fuse_inode_handle parent;

	if (fh_type != 0x82 || fh_len < 6)
		return NULL;

	parent.nodeid = (u64) fid->raw[3] << 32;
	parent.nodeid |= (u64) fid->raw[4];
	parent.generation = fid->raw[5];
	return fuse_get_dentry(sb, &parent);
}

742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758
static struct dentry *fuse_get_parent(struct dentry *child)
{
	struct inode *child_inode = child->d_inode;
	struct fuse_conn *fc = get_fuse_conn(child_inode);
	struct inode *inode;
	struct dentry *parent;
	struct fuse_entry_out outarg;
	struct qstr name;
	int err;

	if (!fc->export_support)
		return ERR_PTR(-ESTALE);

	name.len = 2;
	name.name = "..";
	err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
			       &name, &outarg, &inode);
759 760 761
	if (err) {
		if (err == -ENOENT)
			return ERR_PTR(-ESTALE);
762 763
		return ERR_PTR(err);
	}
764 765

	parent = d_obtain_alias(inode);
A
Al Viro 已提交
766
	if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID)
767 768 769 770
		fuse_invalidate_entry_cache(parent);

	return parent;
}
M
Miklos Szeredi 已提交
771 772 773 774 775

static const struct export_operations fuse_export_operations = {
	.fh_to_dentry	= fuse_fh_to_dentry,
	.fh_to_parent	= fuse_fh_to_parent,
	.encode_fh	= fuse_encode_fh,
776
	.get_parent	= fuse_get_parent,
M
Miklos Szeredi 已提交
777 778
};

779
static const struct super_operations fuse_super_operations = {
M
Miklos Szeredi 已提交
780 781
	.alloc_inode    = fuse_alloc_inode,
	.destroy_inode  = fuse_destroy_inode,
782
	.evict_inode	= fuse_evict_inode,
M
Miklos Szeredi 已提交
783
	.drop_inode	= generic_delete_inode,
784
	.remount_fs	= fuse_remount_fs,
M
Miklos Szeredi 已提交
785
	.put_super	= fuse_put_super,
786
	.umount_begin	= fuse_umount_begin,
787
	.statfs		= fuse_statfs,
M
Miklos Szeredi 已提交
788 789 790
	.show_options	= fuse_show_options,
};

791 792 793
static void sanitize_global_limit(unsigned *limit)
{
	if (*limit == 0)
794
		*limit = ((totalram_pages << PAGE_SHIFT) >> 13) /
795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838
			 sizeof(struct fuse_req);

	if (*limit >= 1 << 16)
		*limit = (1 << 16) - 1;
}

static int set_global_limit(const char *val, struct kernel_param *kp)
{
	int rv;

	rv = param_set_uint(val, kp);
	if (rv)
		return rv;

	sanitize_global_limit((unsigned *)kp->arg);

	return 0;
}

static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg)
{
	int cap_sys_admin = capable(CAP_SYS_ADMIN);

	if (arg->minor < 13)
		return;

	sanitize_global_limit(&max_user_bgreq);
	sanitize_global_limit(&max_user_congthresh);

	if (arg->max_background) {
		fc->max_background = arg->max_background;

		if (!cap_sys_admin && fc->max_background > max_user_bgreq)
			fc->max_background = max_user_bgreq;
	}
	if (arg->congestion_threshold) {
		fc->congestion_threshold = arg->congestion_threshold;

		if (!cap_sys_admin &&
		    fc->congestion_threshold > max_user_congthresh)
			fc->congestion_threshold = max_user_congthresh;
	}
}

839 840 841 842 843 844 845
static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
{
	struct fuse_init_out *arg = &req->misc.init_out;

	if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
		fc->conn_error = 1;
	else {
846 847
		unsigned long ra_pages;

848 849
		process_init_limits(fc, arg);

850 851 852 853
		if (arg->minor >= 6) {
			ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
			if (arg->flags & FUSE_ASYNC_READ)
				fc->async_read = 1;
854 855
			if (!(arg->flags & FUSE_POSIX_LOCKS))
				fc->no_lock = 1;
M
Miklos Szeredi 已提交
856 857 858
			if (arg->minor >= 17) {
				if (!(arg->flags & FUSE_FLOCK_LOCKS))
					fc->no_flock = 1;
M
Miklos Szeredi 已提交
859 860 861
			} else {
				if (!(arg->flags & FUSE_POSIX_LOCKS))
					fc->no_flock = 1;
M
Miklos Szeredi 已提交
862
			}
863 864
			if (arg->flags & FUSE_ATOMIC_O_TRUNC)
				fc->atomic_o_trunc = 1;
865 866 867 868 869
			if (arg->minor >= 9) {
				/* LOOKUP has dependency on proto version */
				if (arg->flags & FUSE_EXPORT_SUPPORT)
					fc->export_support = 1;
			}
870 871
			if (arg->flags & FUSE_BIG_WRITES)
				fc->big_writes = 1;
872 873
			if (arg->flags & FUSE_DONT_MASK)
				fc->dont_mask = 1;
874 875
			if (arg->flags & FUSE_AUTO_INVAL_DATA)
				fc->auto_inval_data = 1;
876
			if (arg->flags & FUSE_DO_READDIRPLUS) {
877
				fc->do_readdirplus = 1;
878 879 880
				if (arg->flags & FUSE_READDIRPLUS_AUTO)
					fc->readdirplus_auto = 1;
			}
881 882
			if (arg->flags & FUSE_ASYNC_DIO)
				fc->async_dio = 1;
883
		} else {
884
			ra_pages = fc->max_read / PAGE_CACHE_SIZE;
885
			fc->no_lock = 1;
M
Miklos Szeredi 已提交
886
			fc->no_flock = 1;
887
		}
888 889

		fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
890 891
		fc->minor = arg->minor;
		fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
892
		fc->max_write = max_t(unsigned, 4096, fc->max_write);
893
		fc->conn_init = 1;
894
	}
M
Maxim Patlasov 已提交
895
	fc->initialized = 1;
896
	wake_up_all(&fc->blocked_waitq);
897 898
}

899
static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
900 901
{
	struct fuse_init_in *arg = &req->misc.init_in;
M
Miklos Szeredi 已提交
902

903 904
	arg->major = FUSE_KERNEL_VERSION;
	arg->minor = FUSE_KERNEL_MINOR_VERSION;
905
	arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
906
	arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
M
Miklos Szeredi 已提交
907
		FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
M
Miklos Szeredi 已提交
908
		FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
909
		FUSE_FLOCK_LOCKS | FUSE_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
910
		FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO;
911 912 913 914 915
	req->in.h.opcode = FUSE_INIT;
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(*arg);
	req->in.args[0].value = arg;
	req->out.numargs = 1;
D
Daniel Mack 已提交
916
	/* Variable length argument used for backward compatibility
917 918 919 920 921 922
	   with interface version < 7.5.  Rest of init_out is zeroed
	   by do_get_request(), so a short reply is not a problem */
	req->out.argvar = 1;
	req->out.args[0].size = sizeof(struct fuse_init_out);
	req->out.args[0].value = &req->misc.init_out;
	req->end = process_init_reply;
923
	fuse_request_send_background(fc, req);
924 925
}

T
Tejun Heo 已提交
926 927
static void fuse_free_conn(struct fuse_conn *fc)
{
A
Al Viro 已提交
928
	kfree_rcu(fc, rcu);
T
Tejun Heo 已提交
929 930
}

931 932 933 934
static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
{
	int err;

935
	fc->bdi.name = "fuse";
936 937
	fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
	/* fuse does it's own writeback accounting */
938
	fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT;
939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972

	err = bdi_init(&fc->bdi);
	if (err)
		return err;

	fc->bdi_initialized = 1;

	if (sb->s_bdev) {
		err =  bdi_register(&fc->bdi, NULL, "%u:%u-fuseblk",
				    MAJOR(fc->dev), MINOR(fc->dev));
	} else {
		err = bdi_register_dev(&fc->bdi, fc->dev);
	}

	if (err)
		return err;

	/*
	 * For a single fuse filesystem use max 1% of dirty +
	 * writeback threshold.
	 *
	 * This gives about 1M of write buffer for memory maps on a
	 * machine with 1G and 10% dirty_ratio, which should be more
	 * than enough.
	 *
	 * Privileged users can raise it by writing to
	 *
	 *    /sys/class/bdi/<bdi>/max_ratio
	 */
	bdi_set_max_ratio(&fc->bdi, 1);

	return 0;
}

M
Miklos Szeredi 已提交
973 974 975 976 977 978
static int fuse_fill_super(struct super_block *sb, void *data, int silent)
{
	struct fuse_conn *fc;
	struct inode *root;
	struct fuse_mount_data d;
	struct file *file;
979
	struct dentry *root_dentry;
980
	struct fuse_req *init_req;
M
Miklos Szeredi 已提交
981
	int err;
M
Miklos Szeredi 已提交
982
	int is_bdev = sb->s_bdev != NULL;
M
Miklos Szeredi 已提交
983

984
	err = -EINVAL;
985
	if (sb->s_flags & MS_MANDLOCK)
986
		goto err;
987

A
Al Viro 已提交
988 989
	sb->s_flags &= ~MS_NOSEC;

M
Miklos Szeredi 已提交
990
	if (!parse_fuse_opt((char *) data, &d, is_bdev))
991
		goto err;
M
Miklos Szeredi 已提交
992

M
Miklos Szeredi 已提交
993
	if (is_bdev) {
994
#ifdef CONFIG_BLOCK
995
		err = -EINVAL;
M
Miklos Szeredi 已提交
996
		if (!sb_set_blocksize(sb, d.blksize))
997
			goto err;
998
#endif
M
Miklos Szeredi 已提交
999 1000 1001 1002
	} else {
		sb->s_blocksize = PAGE_CACHE_SIZE;
		sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	}
M
Miklos Szeredi 已提交
1003 1004 1005
	sb->s_magic = FUSE_SUPER_MAGIC;
	sb->s_op = &fuse_super_operations;
	sb->s_maxbytes = MAX_LFS_FILESIZE;
1006
	sb->s_time_gran = 1;
M
Miklos Szeredi 已提交
1007
	sb->s_export_op = &fuse_export_operations;
M
Miklos Szeredi 已提交
1008 1009

	file = fget(d.fd);
1010
	err = -EINVAL;
M
Miklos Szeredi 已提交
1011
	if (!file)
1012
		goto err;
M
Miklos Szeredi 已提交
1013

1014 1015
	if ((file->f_op != &fuse_dev_operations) ||
	    (file->f_cred->user_ns != &init_user_ns))
1016
		goto err_fput;
M
Miklos Szeredi 已提交
1017

1018
	fc = kmalloc(sizeof(*fc), GFP_KERNEL);
1019 1020 1021
	err = -ENOMEM;
	if (!fc)
		goto err_fput;
M
Miklos Szeredi 已提交
1022

1023 1024 1025
	fuse_conn_init(fc);

	fc->dev = sb->s_dev;
J
John Muir 已提交
1026
	fc->sb = sb;
1027 1028 1029
	err = fuse_bdi_init(fc, sb);
	if (err)
		goto err_put_conn;
1030

J
Jens Axboe 已提交
1031 1032
	sb->s_bdi = &fc->bdi;

1033 1034 1035 1036 1037
	/* Handle umasking inside the fuse code */
	if (sb->s_flags & MS_POSIXACL)
		fc->dont_mask = 1;
	sb->s_flags |= MS_POSIXACL;

T
Tejun Heo 已提交
1038
	fc->release = fuse_free_conn;
M
Miklos Szeredi 已提交
1039
	fc->flags = d.flags;
M
Miklos Szeredi 已提交
1040
	fc->user_id = d.user_id;
1041
	fc->group_id = d.group_id;
1042
	fc->max_read = max_t(unsigned, 4096, d.max_read);
M
Miklos Szeredi 已提交
1043

1044 1045 1046
	/* Used by get_root_inode() */
	sb->s_fs_info = fc;

M
Miklos Szeredi 已提交
1047
	err = -ENOMEM;
1048
	root = fuse_get_root_inode(sb, d.rootmode);
1049 1050
	root_dentry = d_make_root(root);
	if (!root_dentry)
1051
		goto err_put_conn;
A
Al Viro 已提交
1052 1053
	/* only now - we want root dentry with NULL ->d_op */
	sb->s_d_op = &fuse_dentry_operations;
1054

1055
	init_req = fuse_request_alloc(0);
1056 1057
	if (!init_req)
		goto err_put_root;
1058
	init_req->background = 1;
1059

1060
	if (is_bdev) {
1061
		fc->destroy_req = fuse_request_alloc(0);
1062
		if (!fc->destroy_req)
J
Julia Lawall 已提交
1063
			goto err_free_init_req;
1064 1065
	}

1066
	mutex_lock(&fuse_mutex);
1067 1068
	err = -EINVAL;
	if (file->private_data)
1069
		goto err_unlock;
1070

1071 1072 1073 1074 1075
	err = fuse_ctl_add_conn(fc);
	if (err)
		goto err_unlock;

	list_add_tail(&fc->entry, &fuse_conn_list);
1076 1077
	sb->s_root = root_dentry;
	fc->connected = 1;
1078 1079
	file->private_data = fuse_conn_get(fc);
	mutex_unlock(&fuse_mutex);
M
Miklos Szeredi 已提交
1080 1081 1082 1083 1084 1085
	/*
	 * atomic_dec_and_test() in fput() provides the necessary
	 * memory barrier for file->private_data to be visible on all
	 * CPUs after this
	 */
	fput(file);
1086

1087
	fuse_send_init(fc, init_req);
1088

M
Miklos Szeredi 已提交
1089 1090
	return 0;

1091 1092
 err_unlock:
	mutex_unlock(&fuse_mutex);
J
Julia Lawall 已提交
1093
 err_free_init_req:
1094
	fuse_request_free(init_req);
1095 1096
 err_put_root:
	dput(root_dentry);
1097
 err_put_conn:
1098
	fuse_bdi_destroy(fc);
1099
	fuse_conn_put(fc);
1100 1101 1102
 err_fput:
	fput(file);
 err:
M
Miklos Szeredi 已提交
1103 1104 1105
	return err;
}

A
Al Viro 已提交
1106
static struct dentry *fuse_mount(struct file_system_type *fs_type,
1107
		       int flags, const char *dev_name,
A
Al Viro 已提交
1108
		       void *raw_data)
M
Miklos Szeredi 已提交
1109
{
A
Al Viro 已提交
1110
	return mount_nodev(fs_type, flags, raw_data, fuse_fill_super);
M
Miklos Szeredi 已提交
1111 1112
}

J
John Muir 已提交
1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125
static void fuse_kill_sb_anon(struct super_block *sb)
{
	struct fuse_conn *fc = get_fuse_conn_super(sb);

	if (fc) {
		down_write(&fc->killsb);
		fc->sb = NULL;
		up_write(&fc->killsb);
	}

	kill_anon_super(sb);
}

1126 1127 1128
static struct file_system_type fuse_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "fuse",
M
Miklos Szeredi 已提交
1129
	.fs_flags	= FS_HAS_SUBTYPE,
A
Al Viro 已提交
1130
	.mount		= fuse_mount,
J
John Muir 已提交
1131
	.kill_sb	= fuse_kill_sb_anon,
1132
};
1133
MODULE_ALIAS_FS("fuse");
1134 1135

#ifdef CONFIG_BLOCK
A
Al Viro 已提交
1136
static struct dentry *fuse_mount_blk(struct file_system_type *fs_type,
1137
			   int flags, const char *dev_name,
A
Al Viro 已提交
1138
			   void *raw_data)
1139
{
A
Al Viro 已提交
1140
	return mount_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super);
1141 1142
}

J
John Muir 已提交
1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155
static void fuse_kill_sb_blk(struct super_block *sb)
{
	struct fuse_conn *fc = get_fuse_conn_super(sb);

	if (fc) {
		down_write(&fc->killsb);
		fc->sb = NULL;
		up_write(&fc->killsb);
	}

	kill_block_super(sb);
}

1156 1157 1158
static struct file_system_type fuseblk_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "fuseblk",
A
Al Viro 已提交
1159
	.mount		= fuse_mount_blk,
J
John Muir 已提交
1160
	.kill_sb	= fuse_kill_sb_blk,
A
Alexey Dobriyan 已提交
1161
	.fs_flags	= FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
1162
};
1163
MODULE_ALIAS_FS("fuseblk");
1164

1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184
static inline int register_fuseblk(void)
{
	return register_filesystem(&fuseblk_fs_type);
}

static inline void unregister_fuseblk(void)
{
	unregister_filesystem(&fuseblk_fs_type);
}
#else
static inline int register_fuseblk(void)
{
	return 0;
}

static inline void unregister_fuseblk(void)
{
}
#endif

1185
static void fuse_inode_init_once(void *foo)
M
Miklos Szeredi 已提交
1186
{
M
Miklos Szeredi 已提交
1187
	struct inode *inode = foo;
M
Miklos Szeredi 已提交
1188

C
Christoph Lameter 已提交
1189
	inode_init_once(inode);
M
Miklos Szeredi 已提交
1190 1191 1192 1193 1194 1195
}

static int __init fuse_fs_init(void)
{
	int err;

1196 1197 1198
	fuse_inode_cachep = kmem_cache_create("fuse_inode",
					      sizeof(struct fuse_inode),
					      0, SLAB_HWCACHE_ALIGN,
1199
					      fuse_inode_init_once);
1200 1201
	err = -ENOMEM;
	if (!fuse_inode_cachep)
1202 1203 1204 1205 1206 1207 1208 1209 1210
		goto out;

	err = register_fuseblk();
	if (err)
		goto out2;

	err = register_filesystem(&fuse_fs_type);
	if (err)
		goto out3;
1211 1212

	return 0;
M
Miklos Szeredi 已提交
1213

1214
 out3:
1215
	unregister_fuseblk();
1216 1217
 out2:
	kmem_cache_destroy(fuse_inode_cachep);
1218
 out:
M
Miklos Szeredi 已提交
1219 1220 1221 1222 1223 1224
	return err;
}

static void fuse_fs_cleanup(void)
{
	unregister_filesystem(&fuse_fs_type);
1225
	unregister_fuseblk();
1226 1227 1228 1229 1230 1231

	/*
	 * Make sure all delayed rcu free inodes are flushed before we
	 * destroy cache.
	 */
	rcu_barrier();
M
Miklos Szeredi 已提交
1232 1233 1234
	kmem_cache_destroy(fuse_inode_cachep);
}

1235 1236 1237
static struct kobject *fuse_kobj;
static struct kobject *connections_kobj;

1238 1239 1240 1241
static int fuse_sysfs_init(void)
{
	int err;

1242
	fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
1243 1244
	if (!fuse_kobj) {
		err = -ENOMEM;
1245
		goto out_err;
1246
	}
1247

1248 1249 1250
	connections_kobj = kobject_create_and_add("connections", fuse_kobj);
	if (!connections_kobj) {
		err = -ENOMEM;
1251
		goto out_fuse_unregister;
1252
	}
1253 1254 1255 1256

	return 0;

 out_fuse_unregister:
1257
	kobject_put(fuse_kobj);
1258 1259 1260 1261 1262 1263
 out_err:
	return err;
}

static void fuse_sysfs_cleanup(void)
{
1264 1265
	kobject_put(connections_kobj);
	kobject_put(fuse_kobj);
1266 1267
}

M
Miklos Szeredi 已提交
1268 1269 1270 1271
static int __init fuse_init(void)
{
	int res;

M
Miklos Szeredi 已提交
1272
	printk(KERN_INFO "fuse init (API version %i.%i)\n",
M
Miklos Szeredi 已提交
1273 1274
	       FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);

1275
	INIT_LIST_HEAD(&fuse_conn_list);
M
Miklos Szeredi 已提交
1276 1277 1278 1279
	res = fuse_fs_init();
	if (res)
		goto err;

M
Miklos Szeredi 已提交
1280 1281 1282 1283
	res = fuse_dev_init();
	if (res)
		goto err_fs_cleanup;

1284 1285 1286 1287
	res = fuse_sysfs_init();
	if (res)
		goto err_dev_cleanup;

1288 1289 1290 1291
	res = fuse_ctl_init();
	if (res)
		goto err_sysfs_cleanup;

1292 1293 1294
	sanitize_global_limit(&max_user_bgreq);
	sanitize_global_limit(&max_user_congthresh);

M
Miklos Szeredi 已提交
1295 1296
	return 0;

1297 1298
 err_sysfs_cleanup:
	fuse_sysfs_cleanup();
1299 1300
 err_dev_cleanup:
	fuse_dev_cleanup();
M
Miklos Szeredi 已提交
1301 1302
 err_fs_cleanup:
	fuse_fs_cleanup();
M
Miklos Szeredi 已提交
1303 1304 1305 1306 1307 1308 1309 1310
 err:
	return res;
}

static void __exit fuse_exit(void)
{
	printk(KERN_DEBUG "fuse exit\n");

1311
	fuse_ctl_cleanup();
1312
	fuse_sysfs_cleanup();
M
Miklos Szeredi 已提交
1313
	fuse_fs_cleanup();
M
Miklos Szeredi 已提交
1314
	fuse_dev_cleanup();
M
Miklos Szeredi 已提交
1315 1316 1317 1318
}

module_init(fuse_init);
module_exit(fuse_exit);