inode.c 30.4 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_final(&inode->i_data);
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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)
{
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	sync_filesystem(sb);
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	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;
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	/* mtime from server may be stale due to local buffered write */
	if (!fc->writeback_cache || !S_ISREG(inode->i_mode)) {
		inode->i_mtime.tv_sec   = attr->mtime;
		inode->i_mtime.tv_nsec  = attr->mtimensec;
	}
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	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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	inode->i_mtime.tv_sec  = attr->mtime;
	inode->i_mtime.tv_nsec = attr->mtimensec;
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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;
		if (!fc->writeback_cache || !S_ISREG(inode->i_mode))
			inode->i_flags |= 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;
523 524 525
			d->group_id = make_kgid(current_user_ns(), value);
			if (!gid_valid(d->group_id))
				return 0;
526
			d->group_id_present = 1;
527 528
			break;

M
Miklos Szeredi 已提交
529 530 531 532 533 534 535 536
		case OPT_DEFAULT_PERMISSIONS:
			d->flags |= FUSE_DEFAULT_PERMISSIONS;
			break;

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

537 538 539 540 541 542
		case OPT_MAX_READ:
			if (match_int(&args[0], &value))
				return 0;
			d->max_read = value;
			break;

M
Miklos Szeredi 已提交
543 544 545 546 547 548
		case OPT_BLKSIZE:
			if (!is_bdev || match_int(&args[0], &value))
				return 0;
			d->blksize = value;
			break;

M
Miklos Szeredi 已提交
549 550 551 552
		default:
			return 0;
		}
	}
553 554 555

	if (!d->fd_present || !d->rootmode_present ||
	    !d->user_id_present || !d->group_id_present)
M
Miklos Szeredi 已提交
556 557 558 559 560
		return 0;

	return 1;
}

561
static int fuse_show_options(struct seq_file *m, struct dentry *root)
M
Miklos Szeredi 已提交
562
{
563 564
	struct super_block *sb = root->d_sb;
	struct fuse_conn *fc = get_fuse_conn_super(sb);
M
Miklos Szeredi 已提交
565

566 567
	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
568 569 570 571
	if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
		seq_puts(m, ",default_permissions");
	if (fc->flags & FUSE_ALLOW_OTHER)
		seq_puts(m, ",allow_other");
572 573
	if (fc->max_read != ~0)
		seq_printf(m, ",max_read=%u", fc->max_read);
574 575
	if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
		seq_printf(m, ",blksize=%lu", sb->s_blocksize);
M
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576 577 578
	return 0;
}

579
void fuse_conn_init(struct fuse_conn *fc)
M
Miklos Szeredi 已提交
580
{
581 582
	memset(fc, 0, sizeof(*fc));
	spin_lock_init(&fc->lock);
J
John Muir 已提交
583
	init_rwsem(&fc->killsb);
584 585 586 587 588 589 590 591 592 593
	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);
594
	fc->forget_list_tail = &fc->forget_list_head;
595
	atomic_set(&fc->num_waiting, 0);
596 597
	fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND;
	fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD;
598 599 600
	fc->khctr = 0;
	fc->polled_files = RB_ROOT;
	fc->reqctr = 0;
601
	fc->blocked = 0;
M
Maxim Patlasov 已提交
602
	fc->initialized = 0;
603 604
	fc->attr_version = 1;
	get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
M
Miklos Szeredi 已提交
605
}
606
EXPORT_SYMBOL_GPL(fuse_conn_init);
M
Miklos Szeredi 已提交
607

608 609
void fuse_conn_put(struct fuse_conn *fc)
{
610
	if (atomic_dec_and_test(&fc->count)) {
611 612
		if (fc->destroy_req)
			fuse_request_free(fc->destroy_req);
T
Tejun Heo 已提交
613
		fc->release(fc);
614
	}
615
}
616
EXPORT_SYMBOL_GPL(fuse_conn_put);
617 618 619 620 621 622

struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
{
	atomic_inc(&fc->count);
	return fc;
}
623
EXPORT_SYMBOL_GPL(fuse_conn_get);
624

625
static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
M
Miklos Szeredi 已提交
626 627 628 629 630 631
{
	struct fuse_attr attr;
	memset(&attr, 0, sizeof(attr));

	attr.mode = mode;
	attr.ino = FUSE_ROOT_ID;
632
	attr.nlink = 1;
633
	return fuse_iget(sb, 1, 0, &attr, 0, 0);
M
Miklos Szeredi 已提交
634 635
}

M
Miklos Szeredi 已提交
636
struct fuse_inode_handle {
M
Miklos Szeredi 已提交
637 638 639 640 641 642 643
	u64 nodeid;
	u32 generation;
};

static struct dentry *fuse_get_dentry(struct super_block *sb,
				      struct fuse_inode_handle *handle)
{
644
	struct fuse_conn *fc = get_fuse_conn_super(sb);
M
Miklos Szeredi 已提交
645 646 647 648 649 650 651 652
	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);
653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673
	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
674 675 676 677
	err = -ESTALE;
	if (inode->i_generation != handle->generation)
		goto out_iput;

678
	entry = d_obtain_alias(inode);
A
Al Viro 已提交
679
	if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID)
M
Miklos Szeredi 已提交
680 681 682 683 684 685 686 687 688 689
		fuse_invalidate_entry_cache(entry);

	return entry;

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

A
Al Viro 已提交
690 691
static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len,
			   struct inode *parent)
M
Miklos Szeredi 已提交
692
{
A
Al Viro 已提交
693
	int len = parent ? 6 : 3;
M
Miklos Szeredi 已提交
694 695 696
	u64 nodeid;
	u32 generation;

697 698
	if (*max_len < len) {
		*max_len = len;
699
		return  FILEID_INVALID;
700
	}
M
Miklos Szeredi 已提交
701 702 703 704 705 706 707 708

	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
709
	if (parent) {
M
Miklos Szeredi 已提交
710 711 712 713 714 715 716 717 718
		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
719
	return parent ? 0x82 : 0x81;
M
Miklos Szeredi 已提交
720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749
}

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);
}

750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766
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);
767 768 769
	if (err) {
		if (err == -ENOENT)
			return ERR_PTR(-ESTALE);
770 771
		return ERR_PTR(err);
	}
772 773

	parent = d_obtain_alias(inode);
A
Al Viro 已提交
774
	if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID)
775 776 777 778
		fuse_invalidate_entry_cache(parent);

	return parent;
}
M
Miklos Szeredi 已提交
779 780 781 782 783

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,
784
	.get_parent	= fuse_get_parent,
M
Miklos Szeredi 已提交
785 786
};

787
static const struct super_operations fuse_super_operations = {
M
Miklos Szeredi 已提交
788 789
	.alloc_inode    = fuse_alloc_inode,
	.destroy_inode  = fuse_destroy_inode,
790
	.evict_inode	= fuse_evict_inode,
M
Miklos Szeredi 已提交
791
	.drop_inode	= generic_delete_inode,
792
	.remount_fs	= fuse_remount_fs,
M
Miklos Szeredi 已提交
793
	.put_super	= fuse_put_super,
794
	.umount_begin	= fuse_umount_begin,
795
	.statfs		= fuse_statfs,
M
Miklos Szeredi 已提交
796 797 798
	.show_options	= fuse_show_options,
};

799 800 801
static void sanitize_global_limit(unsigned *limit)
{
	if (*limit == 0)
802
		*limit = ((totalram_pages << PAGE_SHIFT) >> 13) /
803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846
			 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;
	}
}

847 848 849 850 851 852 853
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 {
854 855
		unsigned long ra_pages;

856 857
		process_init_limits(fc, arg);

858 859 860 861
		if (arg->minor >= 6) {
			ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
			if (arg->flags & FUSE_ASYNC_READ)
				fc->async_read = 1;
862 863
			if (!(arg->flags & FUSE_POSIX_LOCKS))
				fc->no_lock = 1;
M
Miklos Szeredi 已提交
864 865 866
			if (arg->minor >= 17) {
				if (!(arg->flags & FUSE_FLOCK_LOCKS))
					fc->no_flock = 1;
M
Miklos Szeredi 已提交
867 868 869
			} else {
				if (!(arg->flags & FUSE_POSIX_LOCKS))
					fc->no_flock = 1;
M
Miklos Szeredi 已提交
870
			}
871 872
			if (arg->flags & FUSE_ATOMIC_O_TRUNC)
				fc->atomic_o_trunc = 1;
873 874 875 876 877
			if (arg->minor >= 9) {
				/* LOOKUP has dependency on proto version */
				if (arg->flags & FUSE_EXPORT_SUPPORT)
					fc->export_support = 1;
			}
878 879
			if (arg->flags & FUSE_BIG_WRITES)
				fc->big_writes = 1;
880 881
			if (arg->flags & FUSE_DONT_MASK)
				fc->dont_mask = 1;
882 883
			if (arg->flags & FUSE_AUTO_INVAL_DATA)
				fc->auto_inval_data = 1;
884
			if (arg->flags & FUSE_DO_READDIRPLUS) {
885
				fc->do_readdirplus = 1;
886 887 888
				if (arg->flags & FUSE_READDIRPLUS_AUTO)
					fc->readdirplus_auto = 1;
			}
889 890
			if (arg->flags & FUSE_ASYNC_DIO)
				fc->async_dio = 1;
P
Pavel Emelyanov 已提交
891 892
			if (arg->flags & FUSE_WRITEBACK_CACHE)
				fc->writeback_cache = 1;
893
		} else {
894
			ra_pages = fc->max_read / PAGE_CACHE_SIZE;
895
			fc->no_lock = 1;
M
Miklos Szeredi 已提交
896
			fc->no_flock = 1;
897
		}
898 899

		fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
900 901
		fc->minor = arg->minor;
		fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
902
		fc->max_write = max_t(unsigned, 4096, fc->max_write);
903
		fc->conn_init = 1;
904
	}
M
Maxim Patlasov 已提交
905
	fc->initialized = 1;
906
	wake_up_all(&fc->blocked_waitq);
907 908
}

909
static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
910 911
{
	struct fuse_init_in *arg = &req->misc.init_in;
M
Miklos Szeredi 已提交
912

913 914
	arg->major = FUSE_KERNEL_VERSION;
	arg->minor = FUSE_KERNEL_MINOR_VERSION;
915
	arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
916
	arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
M
Miklos Szeredi 已提交
917
		FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
M
Miklos Szeredi 已提交
918
		FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
919
		FUSE_FLOCK_LOCKS | FUSE_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
P
Pavel Emelyanov 已提交
920 921
		FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO |
		FUSE_WRITEBACK_CACHE;
922 923 924 925 926
	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
927
	/* Variable length argument used for backward compatibility
928 929 930 931 932 933
	   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;
934
	fuse_request_send_background(fc, req);
935 936
}

T
Tejun Heo 已提交
937 938
static void fuse_free_conn(struct fuse_conn *fc)
{
A
Al Viro 已提交
939
	kfree_rcu(fc, rcu);
T
Tejun Heo 已提交
940 941
}

942 943 944 945
static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
{
	int err;

946
	fc->bdi.name = "fuse";
947 948
	fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
	/* fuse does it's own writeback accounting */
949
	fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT;
950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983

	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
984 985 986 987 988 989
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;
990
	struct dentry *root_dentry;
991
	struct fuse_req *init_req;
M
Miklos Szeredi 已提交
992
	int err;
M
Miklos Szeredi 已提交
993
	int is_bdev = sb->s_bdev != NULL;
M
Miklos Szeredi 已提交
994

995
	err = -EINVAL;
996
	if (sb->s_flags & MS_MANDLOCK)
997
		goto err;
998

A
Al Viro 已提交
999 1000
	sb->s_flags &= ~MS_NOSEC;

M
Miklos Szeredi 已提交
1001
	if (!parse_fuse_opt((char *) data, &d, is_bdev))
1002
		goto err;
M
Miklos Szeredi 已提交
1003

M
Miklos Szeredi 已提交
1004
	if (is_bdev) {
1005
#ifdef CONFIG_BLOCK
1006
		err = -EINVAL;
M
Miklos Szeredi 已提交
1007
		if (!sb_set_blocksize(sb, d.blksize))
1008
			goto err;
1009
#endif
M
Miklos Szeredi 已提交
1010 1011 1012 1013
	} else {
		sb->s_blocksize = PAGE_CACHE_SIZE;
		sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	}
M
Miklos Szeredi 已提交
1014 1015 1016
	sb->s_magic = FUSE_SUPER_MAGIC;
	sb->s_op = &fuse_super_operations;
	sb->s_maxbytes = MAX_LFS_FILESIZE;
1017
	sb->s_time_gran = 1;
M
Miklos Szeredi 已提交
1018
	sb->s_export_op = &fuse_export_operations;
M
Miklos Szeredi 已提交
1019 1020

	file = fget(d.fd);
1021
	err = -EINVAL;
M
Miklos Szeredi 已提交
1022
	if (!file)
1023
		goto err;
M
Miklos Szeredi 已提交
1024

1025 1026
	if ((file->f_op != &fuse_dev_operations) ||
	    (file->f_cred->user_ns != &init_user_ns))
1027
		goto err_fput;
M
Miklos Szeredi 已提交
1028

1029
	fc = kmalloc(sizeof(*fc), GFP_KERNEL);
1030 1031 1032
	err = -ENOMEM;
	if (!fc)
		goto err_fput;
M
Miklos Szeredi 已提交
1033

1034 1035 1036
	fuse_conn_init(fc);

	fc->dev = sb->s_dev;
J
John Muir 已提交
1037
	fc->sb = sb;
1038 1039 1040
	err = fuse_bdi_init(fc, sb);
	if (err)
		goto err_put_conn;
1041

J
Jens Axboe 已提交
1042 1043
	sb->s_bdi = &fc->bdi;

1044 1045 1046 1047 1048
	/* 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
1049
	fc->release = fuse_free_conn;
M
Miklos Szeredi 已提交
1050
	fc->flags = d.flags;
M
Miklos Szeredi 已提交
1051
	fc->user_id = d.user_id;
1052
	fc->group_id = d.group_id;
1053
	fc->max_read = max_t(unsigned, 4096, d.max_read);
M
Miklos Szeredi 已提交
1054

1055 1056 1057
	/* Used by get_root_inode() */
	sb->s_fs_info = fc;

M
Miklos Szeredi 已提交
1058
	err = -ENOMEM;
1059
	root = fuse_get_root_inode(sb, d.rootmode);
1060 1061
	root_dentry = d_make_root(root);
	if (!root_dentry)
1062
		goto err_put_conn;
A
Al Viro 已提交
1063 1064
	/* only now - we want root dentry with NULL ->d_op */
	sb->s_d_op = &fuse_dentry_operations;
1065

1066
	init_req = fuse_request_alloc(0);
1067 1068
	if (!init_req)
		goto err_put_root;
1069
	init_req->background = 1;
1070

1071
	if (is_bdev) {
1072
		fc->destroy_req = fuse_request_alloc(0);
1073
		if (!fc->destroy_req)
J
Julia Lawall 已提交
1074
			goto err_free_init_req;
1075 1076
	}

1077
	mutex_lock(&fuse_mutex);
1078 1079
	err = -EINVAL;
	if (file->private_data)
1080
		goto err_unlock;
1081

1082 1083 1084 1085 1086
	err = fuse_ctl_add_conn(fc);
	if (err)
		goto err_unlock;

	list_add_tail(&fc->entry, &fuse_conn_list);
1087 1088
	sb->s_root = root_dentry;
	fc->connected = 1;
1089 1090
	file->private_data = fuse_conn_get(fc);
	mutex_unlock(&fuse_mutex);
M
Miklos Szeredi 已提交
1091 1092 1093 1094 1095 1096
	/*
	 * 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);
1097

1098
	fuse_send_init(fc, init_req);
1099

M
Miklos Szeredi 已提交
1100 1101
	return 0;

1102 1103
 err_unlock:
	mutex_unlock(&fuse_mutex);
J
Julia Lawall 已提交
1104
 err_free_init_req:
1105
	fuse_request_free(init_req);
1106 1107
 err_put_root:
	dput(root_dentry);
1108
 err_put_conn:
1109
	fuse_bdi_destroy(fc);
1110
	fuse_conn_put(fc);
1111 1112 1113
 err_fput:
	fput(file);
 err:
M
Miklos Szeredi 已提交
1114 1115 1116
	return err;
}

A
Al Viro 已提交
1117
static struct dentry *fuse_mount(struct file_system_type *fs_type,
1118
		       int flags, const char *dev_name,
A
Al Viro 已提交
1119
		       void *raw_data)
M
Miklos Szeredi 已提交
1120
{
A
Al Viro 已提交
1121
	return mount_nodev(fs_type, flags, raw_data, fuse_fill_super);
M
Miklos Szeredi 已提交
1122 1123
}

J
John Muir 已提交
1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136
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);
}

1137 1138 1139
static struct file_system_type fuse_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "fuse",
M
Miklos Szeredi 已提交
1140
	.fs_flags	= FS_HAS_SUBTYPE,
A
Al Viro 已提交
1141
	.mount		= fuse_mount,
J
John Muir 已提交
1142
	.kill_sb	= fuse_kill_sb_anon,
1143
};
1144
MODULE_ALIAS_FS("fuse");
1145 1146

#ifdef CONFIG_BLOCK
A
Al Viro 已提交
1147
static struct dentry *fuse_mount_blk(struct file_system_type *fs_type,
1148
			   int flags, const char *dev_name,
A
Al Viro 已提交
1149
			   void *raw_data)
1150
{
A
Al Viro 已提交
1151
	return mount_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super);
1152 1153
}

J
John Muir 已提交
1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166
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);
}

1167 1168 1169
static struct file_system_type fuseblk_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "fuseblk",
A
Al Viro 已提交
1170
	.mount		= fuse_mount_blk,
J
John Muir 已提交
1171
	.kill_sb	= fuse_kill_sb_blk,
A
Alexey Dobriyan 已提交
1172
	.fs_flags	= FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
1173
};
1174
MODULE_ALIAS_FS("fuseblk");
1175

1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195
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

1196
static void fuse_inode_init_once(void *foo)
M
Miklos Szeredi 已提交
1197
{
M
Miklos Szeredi 已提交
1198
	struct inode *inode = foo;
M
Miklos Szeredi 已提交
1199

C
Christoph Lameter 已提交
1200
	inode_init_once(inode);
M
Miklos Szeredi 已提交
1201 1202 1203 1204 1205 1206
}

static int __init fuse_fs_init(void)
{
	int err;

1207 1208 1209
	fuse_inode_cachep = kmem_cache_create("fuse_inode",
					      sizeof(struct fuse_inode),
					      0, SLAB_HWCACHE_ALIGN,
1210
					      fuse_inode_init_once);
1211 1212
	err = -ENOMEM;
	if (!fuse_inode_cachep)
1213 1214 1215 1216 1217 1218 1219 1220 1221
		goto out;

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

	err = register_filesystem(&fuse_fs_type);
	if (err)
		goto out3;
1222 1223

	return 0;
M
Miklos Szeredi 已提交
1224

1225
 out3:
1226
	unregister_fuseblk();
1227 1228
 out2:
	kmem_cache_destroy(fuse_inode_cachep);
1229
 out:
M
Miklos Szeredi 已提交
1230 1231 1232 1233 1234 1235
	return err;
}

static void fuse_fs_cleanup(void)
{
	unregister_filesystem(&fuse_fs_type);
1236
	unregister_fuseblk();
1237 1238 1239 1240 1241 1242

	/*
	 * Make sure all delayed rcu free inodes are flushed before we
	 * destroy cache.
	 */
	rcu_barrier();
M
Miklos Szeredi 已提交
1243 1244 1245
	kmem_cache_destroy(fuse_inode_cachep);
}

1246 1247 1248
static struct kobject *fuse_kobj;
static struct kobject *connections_kobj;

1249 1250 1251 1252
static int fuse_sysfs_init(void)
{
	int err;

1253
	fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
1254 1255
	if (!fuse_kobj) {
		err = -ENOMEM;
1256
		goto out_err;
1257
	}
1258

1259 1260 1261
	connections_kobj = kobject_create_and_add("connections", fuse_kobj);
	if (!connections_kobj) {
		err = -ENOMEM;
1262
		goto out_fuse_unregister;
1263
	}
1264 1265 1266 1267

	return 0;

 out_fuse_unregister:
1268
	kobject_put(fuse_kobj);
1269 1270 1271 1272 1273 1274
 out_err:
	return err;
}

static void fuse_sysfs_cleanup(void)
{
1275 1276
	kobject_put(connections_kobj);
	kobject_put(fuse_kobj);
1277 1278
}

M
Miklos Szeredi 已提交
1279 1280 1281 1282
static int __init fuse_init(void)
{
	int res;

M
Miklos Szeredi 已提交
1283
	printk(KERN_INFO "fuse init (API version %i.%i)\n",
M
Miklos Szeredi 已提交
1284 1285
	       FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);

1286
	INIT_LIST_HEAD(&fuse_conn_list);
M
Miklos Szeredi 已提交
1287 1288 1289 1290
	res = fuse_fs_init();
	if (res)
		goto err;

M
Miklos Szeredi 已提交
1291 1292 1293 1294
	res = fuse_dev_init();
	if (res)
		goto err_fs_cleanup;

1295 1296 1297 1298
	res = fuse_sysfs_init();
	if (res)
		goto err_dev_cleanup;

1299 1300 1301 1302
	res = fuse_ctl_init();
	if (res)
		goto err_sysfs_cleanup;

1303 1304 1305
	sanitize_global_limit(&max_user_bgreq);
	sanitize_global_limit(&max_user_congthresh);

M
Miklos Szeredi 已提交
1306 1307
	return 0;

1308 1309
 err_sysfs_cleanup:
	fuse_sysfs_cleanup();
1310 1311
 err_dev_cleanup:
	fuse_dev_cleanup();
M
Miklos Szeredi 已提交
1312 1313
 err_fs_cleanup:
	fuse_fs_cleanup();
M
Miklos Szeredi 已提交
1314 1315 1316 1317 1318 1319 1320 1321
 err:
	return res;
}

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

1322
	fuse_ctl_cleanup();
1323
	fuse_sysfs_cleanup();
M
Miklos Szeredi 已提交
1324
	fuse_fs_cleanup();
M
Miklos Szeredi 已提交
1325
	fuse_dev_cleanup();
M
Miklos Szeredi 已提交
1326 1327 1328 1329
}

module_init(fuse_init);
module_exit(fuse_exit);