inode.c 30.6 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;
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		if (!fc->writeback_cache || !S_ISREG(attr->mode))
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			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
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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
	.write_inode	= fuse_write_inode,
M
Miklos Szeredi 已提交
792
	.drop_inode	= generic_delete_inode,
793
	.remount_fs	= fuse_remount_fs,
M
Miklos Szeredi 已提交
794
	.put_super	= fuse_put_super,
795
	.umount_begin	= fuse_umount_begin,
796
	.statfs		= fuse_statfs,
M
Miklos Szeredi 已提交
797 798 799
	.show_options	= fuse_show_options,
};

800 801 802
static void sanitize_global_limit(unsigned *limit)
{
	if (*limit == 0)
803
		*limit = ((totalram_pages << PAGE_SHIFT) >> 13) /
804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847
			 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;
	}
}

848 849 850 851 852 853 854
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 {
855 856
		unsigned long ra_pages;

857 858
		process_init_limits(fc, arg);

859 860 861 862
		if (arg->minor >= 6) {
			ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
			if (arg->flags & FUSE_ASYNC_READ)
				fc->async_read = 1;
863 864
			if (!(arg->flags & FUSE_POSIX_LOCKS))
				fc->no_lock = 1;
M
Miklos Szeredi 已提交
865 866 867
			if (arg->minor >= 17) {
				if (!(arg->flags & FUSE_FLOCK_LOCKS))
					fc->no_flock = 1;
M
Miklos Szeredi 已提交
868 869 870
			} else {
				if (!(arg->flags & FUSE_POSIX_LOCKS))
					fc->no_flock = 1;
M
Miklos Szeredi 已提交
871
			}
872 873
			if (arg->flags & FUSE_ATOMIC_O_TRUNC)
				fc->atomic_o_trunc = 1;
874 875 876 877 878
			if (arg->minor >= 9) {
				/* LOOKUP has dependency on proto version */
				if (arg->flags & FUSE_EXPORT_SUPPORT)
					fc->export_support = 1;
			}
879 880
			if (arg->flags & FUSE_BIG_WRITES)
				fc->big_writes = 1;
881 882
			if (arg->flags & FUSE_DONT_MASK)
				fc->dont_mask = 1;
883 884
			if (arg->flags & FUSE_AUTO_INVAL_DATA)
				fc->auto_inval_data = 1;
885
			if (arg->flags & FUSE_DO_READDIRPLUS) {
886
				fc->do_readdirplus = 1;
887 888 889
				if (arg->flags & FUSE_READDIRPLUS_AUTO)
					fc->readdirplus_auto = 1;
			}
890 891
			if (arg->flags & FUSE_ASYNC_DIO)
				fc->async_dio = 1;
P
Pavel Emelyanov 已提交
892 893
			if (arg->flags & FUSE_WRITEBACK_CACHE)
				fc->writeback_cache = 1;
894 895 896 897 898
			if (arg->time_gran && arg->time_gran <= 1000000000)
				fc->sb->s_time_gran = arg->time_gran;
			else
				fc->sb->s_time_gran = 1000000000;

899
		} else {
900
			ra_pages = fc->max_read / PAGE_CACHE_SIZE;
901
			fc->no_lock = 1;
M
Miklos Szeredi 已提交
902
			fc->no_flock = 1;
903
		}
904 905

		fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
906 907
		fc->minor = arg->minor;
		fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
908
		fc->max_write = max_t(unsigned, 4096, fc->max_write);
909
		fc->conn_init = 1;
910
	}
M
Maxim Patlasov 已提交
911
	fc->initialized = 1;
912
	wake_up_all(&fc->blocked_waitq);
913 914
}

915
static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
916 917
{
	struct fuse_init_in *arg = &req->misc.init_in;
M
Miklos Szeredi 已提交
918

919 920
	arg->major = FUSE_KERNEL_VERSION;
	arg->minor = FUSE_KERNEL_MINOR_VERSION;
921
	arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
922
	arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
M
Miklos Szeredi 已提交
923
		FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
M
Miklos Szeredi 已提交
924
		FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
925
		FUSE_FLOCK_LOCKS | FUSE_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
P
Pavel Emelyanov 已提交
926 927
		FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO |
		FUSE_WRITEBACK_CACHE;
928 929 930 931 932
	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
933
	/* Variable length argument used for backward compatibility
934 935 936 937 938 939
	   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;
940
	fuse_request_send_background(fc, req);
941 942
}

T
Tejun Heo 已提交
943 944
static void fuse_free_conn(struct fuse_conn *fc)
{
A
Al Viro 已提交
945
	kfree_rcu(fc, rcu);
T
Tejun Heo 已提交
946 947
}

948 949 950 951
static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
{
	int err;

952
	fc->bdi.name = "fuse";
953 954
	fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
	/* fuse does it's own writeback accounting */
955
	fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT;
956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989

	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
990 991 992 993 994 995
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;
996
	struct dentry *root_dentry;
997
	struct fuse_req *init_req;
M
Miklos Szeredi 已提交
998
	int err;
M
Miklos Szeredi 已提交
999
	int is_bdev = sb->s_bdev != NULL;
M
Miklos Szeredi 已提交
1000

1001
	err = -EINVAL;
1002
	if (sb->s_flags & MS_MANDLOCK)
1003
		goto err;
1004

A
Al Viro 已提交
1005 1006
	sb->s_flags &= ~MS_NOSEC;

M
Miklos Szeredi 已提交
1007
	if (!parse_fuse_opt((char *) data, &d, is_bdev))
1008
		goto err;
M
Miklos Szeredi 已提交
1009

M
Miklos Szeredi 已提交
1010
	if (is_bdev) {
1011
#ifdef CONFIG_BLOCK
1012
		err = -EINVAL;
M
Miklos Szeredi 已提交
1013
		if (!sb_set_blocksize(sb, d.blksize))
1014
			goto err;
1015
#endif
M
Miklos Szeredi 已提交
1016 1017 1018 1019
	} else {
		sb->s_blocksize = PAGE_CACHE_SIZE;
		sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	}
M
Miklos Szeredi 已提交
1020 1021 1022
	sb->s_magic = FUSE_SUPER_MAGIC;
	sb->s_op = &fuse_super_operations;
	sb->s_maxbytes = MAX_LFS_FILESIZE;
1023
	sb->s_time_gran = 1;
M
Miklos Szeredi 已提交
1024
	sb->s_export_op = &fuse_export_operations;
M
Miklos Szeredi 已提交
1025 1026

	file = fget(d.fd);
1027
	err = -EINVAL;
M
Miklos Szeredi 已提交
1028
	if (!file)
1029
		goto err;
M
Miklos Szeredi 已提交
1030

1031 1032
	if ((file->f_op != &fuse_dev_operations) ||
	    (file->f_cred->user_ns != &init_user_ns))
1033
		goto err_fput;
M
Miklos Szeredi 已提交
1034

1035
	fc = kmalloc(sizeof(*fc), GFP_KERNEL);
1036 1037 1038
	err = -ENOMEM;
	if (!fc)
		goto err_fput;
M
Miklos Szeredi 已提交
1039

1040 1041 1042
	fuse_conn_init(fc);

	fc->dev = sb->s_dev;
J
John Muir 已提交
1043
	fc->sb = sb;
1044 1045 1046
	err = fuse_bdi_init(fc, sb);
	if (err)
		goto err_put_conn;
1047

J
Jens Axboe 已提交
1048 1049
	sb->s_bdi = &fc->bdi;

1050 1051 1052 1053 1054
	/* 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
1055
	fc->release = fuse_free_conn;
M
Miklos Szeredi 已提交
1056
	fc->flags = d.flags;
M
Miklos Szeredi 已提交
1057
	fc->user_id = d.user_id;
1058
	fc->group_id = d.group_id;
1059
	fc->max_read = max_t(unsigned, 4096, d.max_read);
M
Miklos Szeredi 已提交
1060

1061 1062 1063
	/* Used by get_root_inode() */
	sb->s_fs_info = fc;

M
Miklos Szeredi 已提交
1064
	err = -ENOMEM;
1065
	root = fuse_get_root_inode(sb, d.rootmode);
1066 1067
	root_dentry = d_make_root(root);
	if (!root_dentry)
1068
		goto err_put_conn;
A
Al Viro 已提交
1069 1070
	/* only now - we want root dentry with NULL ->d_op */
	sb->s_d_op = &fuse_dentry_operations;
1071

1072
	init_req = fuse_request_alloc(0);
1073 1074
	if (!init_req)
		goto err_put_root;
1075
	init_req->background = 1;
1076

1077
	if (is_bdev) {
1078
		fc->destroy_req = fuse_request_alloc(0);
1079
		if (!fc->destroy_req)
J
Julia Lawall 已提交
1080
			goto err_free_init_req;
1081 1082
	}

1083
	mutex_lock(&fuse_mutex);
1084 1085
	err = -EINVAL;
	if (file->private_data)
1086
		goto err_unlock;
1087

1088 1089 1090 1091 1092
	err = fuse_ctl_add_conn(fc);
	if (err)
		goto err_unlock;

	list_add_tail(&fc->entry, &fuse_conn_list);
1093 1094
	sb->s_root = root_dentry;
	fc->connected = 1;
1095 1096
	file->private_data = fuse_conn_get(fc);
	mutex_unlock(&fuse_mutex);
M
Miklos Szeredi 已提交
1097 1098 1099 1100 1101 1102
	/*
	 * 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);
1103

1104
	fuse_send_init(fc, init_req);
1105

M
Miklos Szeredi 已提交
1106 1107
	return 0;

1108 1109
 err_unlock:
	mutex_unlock(&fuse_mutex);
J
Julia Lawall 已提交
1110
 err_free_init_req:
1111
	fuse_request_free(init_req);
1112 1113
 err_put_root:
	dput(root_dentry);
1114
 err_put_conn:
1115
	fuse_bdi_destroy(fc);
1116
	fuse_conn_put(fc);
1117 1118 1119
 err_fput:
	fput(file);
 err:
M
Miklos Szeredi 已提交
1120 1121 1122
	return err;
}

A
Al Viro 已提交
1123
static struct dentry *fuse_mount(struct file_system_type *fs_type,
1124
		       int flags, const char *dev_name,
A
Al Viro 已提交
1125
		       void *raw_data)
M
Miklos Szeredi 已提交
1126
{
A
Al Viro 已提交
1127
	return mount_nodev(fs_type, flags, raw_data, fuse_fill_super);
M
Miklos Szeredi 已提交
1128 1129
}

J
John Muir 已提交
1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142
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);
}

1143 1144 1145
static struct file_system_type fuse_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "fuse",
M
Miklos Szeredi 已提交
1146
	.fs_flags	= FS_HAS_SUBTYPE,
A
Al Viro 已提交
1147
	.mount		= fuse_mount,
J
John Muir 已提交
1148
	.kill_sb	= fuse_kill_sb_anon,
1149
};
1150
MODULE_ALIAS_FS("fuse");
1151 1152

#ifdef CONFIG_BLOCK
A
Al Viro 已提交
1153
static struct dentry *fuse_mount_blk(struct file_system_type *fs_type,
1154
			   int flags, const char *dev_name,
A
Al Viro 已提交
1155
			   void *raw_data)
1156
{
A
Al Viro 已提交
1157
	return mount_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super);
1158 1159
}

J
John Muir 已提交
1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172
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);
}

1173 1174 1175
static struct file_system_type fuseblk_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "fuseblk",
A
Al Viro 已提交
1176
	.mount		= fuse_mount_blk,
J
John Muir 已提交
1177
	.kill_sb	= fuse_kill_sb_blk,
A
Alexey Dobriyan 已提交
1178
	.fs_flags	= FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
1179
};
1180
MODULE_ALIAS_FS("fuseblk");
1181

1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201
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

1202
static void fuse_inode_init_once(void *foo)
M
Miklos Szeredi 已提交
1203
{
M
Miklos Szeredi 已提交
1204
	struct inode *inode = foo;
M
Miklos Szeredi 已提交
1205

C
Christoph Lameter 已提交
1206
	inode_init_once(inode);
M
Miklos Szeredi 已提交
1207 1208 1209 1210 1211 1212
}

static int __init fuse_fs_init(void)
{
	int err;

1213 1214 1215
	fuse_inode_cachep = kmem_cache_create("fuse_inode",
					      sizeof(struct fuse_inode),
					      0, SLAB_HWCACHE_ALIGN,
1216
					      fuse_inode_init_once);
1217 1218
	err = -ENOMEM;
	if (!fuse_inode_cachep)
1219 1220 1221 1222 1223 1224 1225 1226 1227
		goto out;

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

	err = register_filesystem(&fuse_fs_type);
	if (err)
		goto out3;
1228 1229

	return 0;
M
Miklos Szeredi 已提交
1230

1231
 out3:
1232
	unregister_fuseblk();
1233 1234
 out2:
	kmem_cache_destroy(fuse_inode_cachep);
1235
 out:
M
Miklos Szeredi 已提交
1236 1237 1238 1239 1240 1241
	return err;
}

static void fuse_fs_cleanup(void)
{
	unregister_filesystem(&fuse_fs_type);
1242
	unregister_fuseblk();
1243 1244 1245 1246 1247 1248

	/*
	 * Make sure all delayed rcu free inodes are flushed before we
	 * destroy cache.
	 */
	rcu_barrier();
M
Miklos Szeredi 已提交
1249 1250 1251
	kmem_cache_destroy(fuse_inode_cachep);
}

1252 1253 1254
static struct kobject *fuse_kobj;
static struct kobject *connections_kobj;

1255 1256 1257 1258
static int fuse_sysfs_init(void)
{
	int err;

1259
	fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
1260 1261
	if (!fuse_kobj) {
		err = -ENOMEM;
1262
		goto out_err;
1263
	}
1264

1265 1266 1267
	connections_kobj = kobject_create_and_add("connections", fuse_kobj);
	if (!connections_kobj) {
		err = -ENOMEM;
1268
		goto out_fuse_unregister;
1269
	}
1270 1271 1272 1273

	return 0;

 out_fuse_unregister:
1274
	kobject_put(fuse_kobj);
1275 1276 1277 1278 1279 1280
 out_err:
	return err;
}

static void fuse_sysfs_cleanup(void)
{
1281 1282
	kobject_put(connections_kobj);
	kobject_put(fuse_kobj);
1283 1284
}

M
Miklos Szeredi 已提交
1285 1286 1287 1288
static int __init fuse_init(void)
{
	int res;

M
Miklos Szeredi 已提交
1289
	printk(KERN_INFO "fuse init (API version %i.%i)\n",
M
Miklos Szeredi 已提交
1290 1291
	       FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);

1292
	INIT_LIST_HEAD(&fuse_conn_list);
M
Miklos Szeredi 已提交
1293 1294 1295 1296
	res = fuse_fs_init();
	if (res)
		goto err;

M
Miklos Szeredi 已提交
1297 1298 1299 1300
	res = fuse_dev_init();
	if (res)
		goto err_fs_cleanup;

1301 1302 1303 1304
	res = fuse_sysfs_init();
	if (res)
		goto err_dev_cleanup;

1305 1306 1307 1308
	res = fuse_ctl_init();
	if (res)
		goto err_sysfs_cleanup;

1309 1310 1311
	sanitize_global_limit(&max_user_bgreq);
	sanitize_global_limit(&max_user_congthresh);

M
Miklos Szeredi 已提交
1312 1313
	return 0;

1314 1315
 err_sysfs_cleanup:
	fuse_sysfs_cleanup();
1316 1317
 err_dev_cleanup:
	fuse_dev_cleanup();
M
Miklos Szeredi 已提交
1318 1319
 err_fs_cleanup:
	fuse_fs_cleanup();
M
Miklos Szeredi 已提交
1320 1321 1322 1323 1324 1325 1326 1327
 err:
	return res;
}

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

1328
	fuse_ctl_cleanup();
1329
	fuse_sysfs_cleanup();
M
Miklos Szeredi 已提交
1330
	fuse_fs_cleanup();
M
Miklos Szeredi 已提交
1331
	fuse_dev_cleanup();
M
Miklos Szeredi 已提交
1332 1333 1334 1335
}

module_init(fuse_init);
module_exit(fuse_exit);