inode.c 31.3 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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	}
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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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	inode->i_ctime.tv_sec  = attr->ctime;
	inode->i_ctime.tv_nsec = attr->ctimensec;
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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;
		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) {
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		pg_start = offset >> PAGE_SHIFT;
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		if (len <= 0)
			pg_end = -1;
		else
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			pg_end = (offset + len - 1) >> PAGE_SHIFT;
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		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;
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		__set_bit(FR_FORCE, &req->flags);
		__clear_bit(FR_BACKGROUND, &req->flags);
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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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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_abort_conn(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);
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	FUSE_ARGS(args);
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	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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	memset(&outarg, 0, sizeof(outarg));
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	args.in.numargs = 0;
	args.in.h.opcode = FUSE_STATFS;
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	args.in.h.nodeid = get_node_id(d_inode(dentry));
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	args.out.numargs = 1;
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	args.out.args[0].size = sizeof(outarg);
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	args.out.args[0].value = &outarg;
	err = fuse_simple_request(fc, &args);
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	if (!err)
		convert_fuse_statfs(buf, &outarg.st);
	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 fuse_match_uint(substring_t *s, unsigned int *res)
{
	int err = -ENOMEM;
	char *buf = match_strdup(s);
	if (buf) {
		err = kstrtouint(buf, 10, res);
		kfree(buf);
	}
	return err;
}

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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;
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		unsigned uv;
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		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:
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			if (fuse_match_uint(&args[0], &uv))
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				return 0;
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			d->user_id = make_kuid(current_user_ns(), uv);
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			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:
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			if (fuse_match_uint(&args[0], &uv))
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				return 0;
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			d->group_id = make_kgid(current_user_ns(), uv);
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			if (!gid_valid(d->group_id))
				return 0;
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			d->group_id_present = 1;
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			break;

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Miklos Szeredi 已提交
520 521 522 523 524 525 526 527
		case OPT_DEFAULT_PERMISSIONS:
			d->flags |= FUSE_DEFAULT_PERMISSIONS;
			break;

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

528 529 530 531 532 533
		case OPT_MAX_READ:
			if (match_int(&args[0], &value))
				return 0;
			d->max_read = value;
			break;

M
Miklos Szeredi 已提交
534 535 536 537 538 539
		case OPT_BLKSIZE:
			if (!is_bdev || match_int(&args[0], &value))
				return 0;
			d->blksize = value;
			break;

M
Miklos Szeredi 已提交
540 541 542 543
		default:
			return 0;
		}
	}
544 545 546

	if (!d->fd_present || !d->rootmode_present ||
	    !d->user_id_present || !d->group_id_present)
M
Miklos Szeredi 已提交
547 548 549 550 551
		return 0;

	return 1;
}

552
static int fuse_show_options(struct seq_file *m, struct dentry *root)
M
Miklos Szeredi 已提交
553
{
554 555
	struct super_block *sb = root->d_sb;
	struct fuse_conn *fc = get_fuse_conn_super(sb);
M
Miklos Szeredi 已提交
556

557 558
	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
559 560 561 562
	if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
		seq_puts(m, ",default_permissions");
	if (fc->flags & FUSE_ALLOW_OTHER)
		seq_puts(m, ",allow_other");
563 564
	if (fc->max_read != ~0)
		seq_printf(m, ",max_read=%u", fc->max_read);
565 566
	if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
		seq_printf(m, ",blksize=%lu", sb->s_blocksize);
M
Miklos Szeredi 已提交
567 568 569
	return 0;
}

M
Miklos Szeredi 已提交
570 571 572 573 574 575 576
static void fuse_iqueue_init(struct fuse_iqueue *fiq)
{
	memset(fiq, 0, sizeof(struct fuse_iqueue));
	init_waitqueue_head(&fiq->waitq);
	INIT_LIST_HEAD(&fiq->pending);
	INIT_LIST_HEAD(&fiq->interrupts);
	fiq->forget_list_tail = &fiq->forget_list_head;
577
	fiq->connected = 1;
M
Miklos Szeredi 已提交
578 579
}

580 581 582
static void fuse_pqueue_init(struct fuse_pqueue *fpq)
{
	memset(fpq, 0, sizeof(struct fuse_pqueue));
M
Miklos Szeredi 已提交
583
	spin_lock_init(&fpq->lock);
584 585
	INIT_LIST_HEAD(&fpq->processing);
	INIT_LIST_HEAD(&fpq->io);
586
	fpq->connected = 1;
587 588
}

589
void fuse_conn_init(struct fuse_conn *fc)
M
Miklos Szeredi 已提交
590
{
591 592
	memset(fc, 0, sizeof(*fc));
	spin_lock_init(&fc->lock);
J
John Muir 已提交
593
	init_rwsem(&fc->killsb);
594
	atomic_set(&fc->count, 1);
595
	atomic_set(&fc->dev_count, 1);
596 597
	init_waitqueue_head(&fc->blocked_waitq);
	init_waitqueue_head(&fc->reserved_req_waitq);
M
Miklos Szeredi 已提交
598
	fuse_iqueue_init(&fc->iq);
599 600
	INIT_LIST_HEAD(&fc->bg_queue);
	INIT_LIST_HEAD(&fc->entry);
601
	INIT_LIST_HEAD(&fc->devices);
602
	atomic_set(&fc->num_waiting, 0);
603 604
	fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND;
	fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD;
605 606
	fc->khctr = 0;
	fc->polled_files = RB_ROOT;
607
	fc->blocked = 0;
M
Maxim Patlasov 已提交
608
	fc->initialized = 0;
609
	fc->connected = 1;
610 611
	fc->attr_version = 1;
	get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
M
Miklos Szeredi 已提交
612
}
613
EXPORT_SYMBOL_GPL(fuse_conn_init);
M
Miklos Szeredi 已提交
614

615 616
void fuse_conn_put(struct fuse_conn *fc)
{
617
	if (atomic_dec_and_test(&fc->count)) {
618 619
		if (fc->destroy_req)
			fuse_request_free(fc->destroy_req);
T
Tejun Heo 已提交
620
		fc->release(fc);
621
	}
622
}
623
EXPORT_SYMBOL_GPL(fuse_conn_put);
624 625 626 627 628 629

struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
{
	atomic_inc(&fc->count);
	return fc;
}
630
EXPORT_SYMBOL_GPL(fuse_conn_get);
631

632
static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
M
Miklos Szeredi 已提交
633 634 635 636 637 638
{
	struct fuse_attr attr;
	memset(&attr, 0, sizeof(attr));

	attr.mode = mode;
	attr.ino = FUSE_ROOT_ID;
639
	attr.nlink = 1;
640
	return fuse_iget(sb, 1, 0, &attr, 0, 0);
M
Miklos Szeredi 已提交
641 642
}

M
Miklos Szeredi 已提交
643
struct fuse_inode_handle {
M
Miklos Szeredi 已提交
644 645 646 647 648 649 650
	u64 nodeid;
	u32 generation;
};

static struct dentry *fuse_get_dentry(struct super_block *sb,
				      struct fuse_inode_handle *handle)
{
651
	struct fuse_conn *fc = get_fuse_conn_super(sb);
M
Miklos Szeredi 已提交
652 653 654 655 656 657 658 659
	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);
660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680
	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
681 682 683 684
	err = -ESTALE;
	if (inode->i_generation != handle->generation)
		goto out_iput;

685
	entry = d_obtain_alias(inode);
A
Al Viro 已提交
686
	if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID)
M
Miklos Szeredi 已提交
687 688 689 690 691 692 693 694 695 696
		fuse_invalidate_entry_cache(entry);

	return entry;

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

A
Al Viro 已提交
697 698
static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len,
			   struct inode *parent)
M
Miklos Szeredi 已提交
699
{
A
Al Viro 已提交
700
	int len = parent ? 6 : 3;
M
Miklos Szeredi 已提交
701 702 703
	u64 nodeid;
	u32 generation;

704 705
	if (*max_len < len) {
		*max_len = len;
706
		return  FILEID_INVALID;
707
	}
M
Miklos Szeredi 已提交
708 709 710 711 712 713 714 715

	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
716
	if (parent) {
M
Miklos Szeredi 已提交
717 718 719 720 721 722 723 724 725
		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
726
	return parent ? 0x82 : 0x81;
M
Miklos Szeredi 已提交
727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756
}

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);
}

757 758
static struct dentry *fuse_get_parent(struct dentry *child)
{
759
	struct inode *child_inode = d_inode(child);
760 761 762 763 764 765 766 767 768 769 770 771 772 773
	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);
774 775 776
	if (err) {
		if (err == -ENOENT)
			return ERR_PTR(-ESTALE);
777 778
		return ERR_PTR(err);
	}
779 780

	parent = d_obtain_alias(inode);
A
Al Viro 已提交
781
	if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID)
782 783 784 785
		fuse_invalidate_entry_cache(parent);

	return parent;
}
M
Miklos Szeredi 已提交
786 787 788 789 790

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,
791
	.get_parent	= fuse_get_parent,
M
Miklos Szeredi 已提交
792 793
};

794
static const struct super_operations fuse_super_operations = {
M
Miklos Szeredi 已提交
795 796
	.alloc_inode    = fuse_alloc_inode,
	.destroy_inode  = fuse_destroy_inode,
797
	.evict_inode	= fuse_evict_inode,
M
Miklos Szeredi 已提交
798
	.write_inode	= fuse_write_inode,
M
Miklos Szeredi 已提交
799
	.drop_inode	= generic_delete_inode,
800
	.remount_fs	= fuse_remount_fs,
M
Miklos Szeredi 已提交
801
	.put_super	= fuse_put_super,
802
	.umount_begin	= fuse_umount_begin,
803
	.statfs		= fuse_statfs,
M
Miklos Szeredi 已提交
804 805 806
	.show_options	= fuse_show_options,
};

807 808 809
static void sanitize_global_limit(unsigned *limit)
{
	if (*limit == 0)
810
		*limit = ((totalram_pages << PAGE_SHIFT) >> 13) /
811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854
			 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;
	}
}

855 856 857 858 859 860 861
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 {
862 863
		unsigned long ra_pages;

864 865
		process_init_limits(fc, arg);

866
		if (arg->minor >= 6) {
867
			ra_pages = arg->max_readahead / PAGE_SIZE;
868 869
			if (arg->flags & FUSE_ASYNC_READ)
				fc->async_read = 1;
870 871
			if (!(arg->flags & FUSE_POSIX_LOCKS))
				fc->no_lock = 1;
M
Miklos Szeredi 已提交
872 873 874
			if (arg->minor >= 17) {
				if (!(arg->flags & FUSE_FLOCK_LOCKS))
					fc->no_flock = 1;
M
Miklos Szeredi 已提交
875 876 877
			} else {
				if (!(arg->flags & FUSE_POSIX_LOCKS))
					fc->no_flock = 1;
M
Miklos Szeredi 已提交
878
			}
879 880
			if (arg->flags & FUSE_ATOMIC_O_TRUNC)
				fc->atomic_o_trunc = 1;
881 882 883 884 885
			if (arg->minor >= 9) {
				/* LOOKUP has dependency on proto version */
				if (arg->flags & FUSE_EXPORT_SUPPORT)
					fc->export_support = 1;
			}
886 887
			if (arg->flags & FUSE_BIG_WRITES)
				fc->big_writes = 1;
888 889
			if (arg->flags & FUSE_DONT_MASK)
				fc->dont_mask = 1;
890 891
			if (arg->flags & FUSE_AUTO_INVAL_DATA)
				fc->auto_inval_data = 1;
892
			if (arg->flags & FUSE_DO_READDIRPLUS) {
893
				fc->do_readdirplus = 1;
894 895 896
				if (arg->flags & FUSE_READDIRPLUS_AUTO)
					fc->readdirplus_auto = 1;
			}
897 898
			if (arg->flags & FUSE_ASYNC_DIO)
				fc->async_dio = 1;
P
Pavel Emelyanov 已提交
899 900
			if (arg->flags & FUSE_WRITEBACK_CACHE)
				fc->writeback_cache = 1;
901 902
			if (arg->time_gran && arg->time_gran <= 1000000000)
				fc->sb->s_time_gran = arg->time_gran;
903
		} else {
904
			ra_pages = fc->max_read / PAGE_SIZE;
905
			fc->no_lock = 1;
M
Miklos Szeredi 已提交
906
			fc->no_flock = 1;
907
		}
908 909

		fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
910 911
		fc->minor = arg->minor;
		fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
912
		fc->max_write = max_t(unsigned, 4096, fc->max_write);
913
		fc->conn_init = 1;
914
	}
915
	fuse_set_initialized(fc);
916
	wake_up_all(&fc->blocked_waitq);
917 918
}

919
static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
920 921
{
	struct fuse_init_in *arg = &req->misc.init_in;
M
Miklos Szeredi 已提交
922

923 924
	arg->major = FUSE_KERNEL_VERSION;
	arg->minor = FUSE_KERNEL_MINOR_VERSION;
925
	arg->max_readahead = fc->bdi.ra_pages * PAGE_SIZE;
926
	arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
M
Miklos Szeredi 已提交
927
		FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
M
Miklos Szeredi 已提交
928
		FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
929
		FUSE_FLOCK_LOCKS | FUSE_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
P
Pavel Emelyanov 已提交
930
		FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO |
931
		FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT;
932 933 934 935 936
	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
937
	/* Variable length argument used for backward compatibility
938 939 940 941 942 943
	   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;
944
	fuse_request_send_background(fc, req);
945 946
}

T
Tejun Heo 已提交
947 948
static void fuse_free_conn(struct fuse_conn *fc)
{
949
	WARN_ON(!list_empty(&fc->devices));
A
Al Viro 已提交
950
	kfree_rcu(fc, rcu);
T
Tejun Heo 已提交
951 952
}

953 954 955 956
static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
{
	int err;

957
	fc->bdi.name = "fuse";
958
	fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_SIZE;
959
	/* fuse does it's own writeback accounting */
960
	fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT;
961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994

	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;
}

995 996 997 998 999 1000 1001
struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc)
{
	struct fuse_dev *fud;

	fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL);
	if (fud) {
		fud->fc = fuse_conn_get(fc);
1002
		fuse_pqueue_init(&fud->pq);
1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027

		spin_lock(&fc->lock);
		list_add_tail(&fud->entry, &fc->devices);
		spin_unlock(&fc->lock);
	}

	return fud;
}
EXPORT_SYMBOL_GPL(fuse_dev_alloc);

void fuse_dev_free(struct fuse_dev *fud)
{
	struct fuse_conn *fc = fud->fc;

	if (fc) {
		spin_lock(&fc->lock);
		list_del(&fud->entry);
		spin_unlock(&fc->lock);

		fuse_conn_put(fc);
	}
	kfree(fud);
}
EXPORT_SYMBOL_GPL(fuse_dev_free);

M
Miklos Szeredi 已提交
1028 1029
static int fuse_fill_super(struct super_block *sb, void *data, int silent)
{
1030
	struct fuse_dev *fud;
M
Miklos Szeredi 已提交
1031 1032 1033 1034
	struct fuse_conn *fc;
	struct inode *root;
	struct fuse_mount_data d;
	struct file *file;
1035
	struct dentry *root_dentry;
1036
	struct fuse_req *init_req;
M
Miklos Szeredi 已提交
1037
	int err;
M
Miklos Szeredi 已提交
1038
	int is_bdev = sb->s_bdev != NULL;
M
Miklos Szeredi 已提交
1039

1040
	err = -EINVAL;
1041
	if (sb->s_flags & MS_MANDLOCK)
1042
		goto err;
1043

M
Miklos Szeredi 已提交
1044
	sb->s_flags &= ~(MS_NOSEC | MS_I_VERSION);
A
Al Viro 已提交
1045

H
Himangi Saraogi 已提交
1046
	if (!parse_fuse_opt(data, &d, is_bdev))
1047
		goto err;
M
Miklos Szeredi 已提交
1048

M
Miklos Szeredi 已提交
1049
	if (is_bdev) {
1050
#ifdef CONFIG_BLOCK
1051
		err = -EINVAL;
M
Miklos Szeredi 已提交
1052
		if (!sb_set_blocksize(sb, d.blksize))
1053
			goto err;
1054
#endif
M
Miklos Szeredi 已提交
1055
	} else {
1056 1057
		sb->s_blocksize = PAGE_SIZE;
		sb->s_blocksize_bits = PAGE_SHIFT;
M
Miklos Szeredi 已提交
1058
	}
M
Miklos Szeredi 已提交
1059 1060 1061
	sb->s_magic = FUSE_SUPER_MAGIC;
	sb->s_op = &fuse_super_operations;
	sb->s_maxbytes = MAX_LFS_FILESIZE;
1062
	sb->s_time_gran = 1;
M
Miklos Szeredi 已提交
1063
	sb->s_export_op = &fuse_export_operations;
M
Miklos Szeredi 已提交
1064 1065

	file = fget(d.fd);
1066
	err = -EINVAL;
M
Miklos Szeredi 已提交
1067
	if (!file)
1068
		goto err;
M
Miklos Szeredi 已提交
1069

1070 1071
	if ((file->f_op != &fuse_dev_operations) ||
	    (file->f_cred->user_ns != &init_user_ns))
1072
		goto err_fput;
M
Miklos Szeredi 已提交
1073

1074
	fc = kmalloc(sizeof(*fc), GFP_KERNEL);
1075 1076 1077
	err = -ENOMEM;
	if (!fc)
		goto err_fput;
M
Miklos Szeredi 已提交
1078

1079
	fuse_conn_init(fc);
1080
	fc->release = fuse_free_conn;
1081

1082 1083 1084 1085
	fud = fuse_dev_alloc(fc);
	if (!fud)
		goto err_put_conn;

1086
	fc->dev = sb->s_dev;
J
John Muir 已提交
1087
	fc->sb = sb;
1088 1089
	err = fuse_bdi_init(fc, sb);
	if (err)
1090
		goto err_dev_free;
1091

J
Jens Axboe 已提交
1092 1093
	sb->s_bdi = &fc->bdi;

1094 1095 1096 1097 1098
	/* Handle umasking inside the fuse code */
	if (sb->s_flags & MS_POSIXACL)
		fc->dont_mask = 1;
	sb->s_flags |= MS_POSIXACL;

M
Miklos Szeredi 已提交
1099
	fc->flags = d.flags;
M
Miklos Szeredi 已提交
1100
	fc->user_id = d.user_id;
1101
	fc->group_id = d.group_id;
1102
	fc->max_read = max_t(unsigned, 4096, d.max_read);
M
Miklos Szeredi 已提交
1103

1104 1105 1106
	/* Used by get_root_inode() */
	sb->s_fs_info = fc;

M
Miklos Szeredi 已提交
1107
	err = -ENOMEM;
1108
	root = fuse_get_root_inode(sb, d.rootmode);
1109 1110
	root_dentry = d_make_root(root);
	if (!root_dentry)
1111
		goto err_dev_free;
A
Al Viro 已提交
1112 1113
	/* only now - we want root dentry with NULL ->d_op */
	sb->s_d_op = &fuse_dentry_operations;
1114

1115
	init_req = fuse_request_alloc(0);
1116 1117
	if (!init_req)
		goto err_put_root;
M
Miklos Szeredi 已提交
1118
	__set_bit(FR_BACKGROUND, &init_req->flags);
1119

1120
	if (is_bdev) {
1121
		fc->destroy_req = fuse_request_alloc(0);
1122
		if (!fc->destroy_req)
J
Julia Lawall 已提交
1123
			goto err_free_init_req;
1124 1125
	}

1126
	mutex_lock(&fuse_mutex);
1127 1128
	err = -EINVAL;
	if (file->private_data)
1129
		goto err_unlock;
1130

1131 1132 1133 1134 1135
	err = fuse_ctl_add_conn(fc);
	if (err)
		goto err_unlock;

	list_add_tail(&fc->entry, &fuse_conn_list);
1136
	sb->s_root = root_dentry;
1137
	file->private_data = fud;
1138
	mutex_unlock(&fuse_mutex);
M
Miklos Szeredi 已提交
1139 1140 1141 1142 1143 1144
	/*
	 * 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);
1145

1146
	fuse_send_init(fc, init_req);
1147

M
Miklos Szeredi 已提交
1148 1149
	return 0;

1150 1151
 err_unlock:
	mutex_unlock(&fuse_mutex);
J
Julia Lawall 已提交
1152
 err_free_init_req:
1153
	fuse_request_free(init_req);
1154 1155
 err_put_root:
	dput(root_dentry);
1156 1157
 err_dev_free:
	fuse_dev_free(fud);
1158
 err_put_conn:
1159
	fuse_bdi_destroy(fc);
1160
	fuse_conn_put(fc);
1161 1162 1163
 err_fput:
	fput(file);
 err:
M
Miklos Szeredi 已提交
1164 1165 1166
	return err;
}

A
Al Viro 已提交
1167
static struct dentry *fuse_mount(struct file_system_type *fs_type,
1168
		       int flags, const char *dev_name,
A
Al Viro 已提交
1169
		       void *raw_data)
M
Miklos Szeredi 已提交
1170
{
A
Al Viro 已提交
1171
	return mount_nodev(fs_type, flags, raw_data, fuse_fill_super);
M
Miklos Szeredi 已提交
1172 1173
}

J
John Muir 已提交
1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186
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);
}

1187 1188 1189
static struct file_system_type fuse_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "fuse",
M
Miklos Szeredi 已提交
1190
	.fs_flags	= FS_HAS_SUBTYPE,
A
Al Viro 已提交
1191
	.mount		= fuse_mount,
J
John Muir 已提交
1192
	.kill_sb	= fuse_kill_sb_anon,
1193
};
1194
MODULE_ALIAS_FS("fuse");
1195 1196

#ifdef CONFIG_BLOCK
A
Al Viro 已提交
1197
static struct dentry *fuse_mount_blk(struct file_system_type *fs_type,
1198
			   int flags, const char *dev_name,
A
Al Viro 已提交
1199
			   void *raw_data)
1200
{
A
Al Viro 已提交
1201
	return mount_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super);
1202 1203
}

J
John Muir 已提交
1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216
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);
}

1217 1218 1219
static struct file_system_type fuseblk_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "fuseblk",
A
Al Viro 已提交
1220
	.mount		= fuse_mount_blk,
J
John Muir 已提交
1221
	.kill_sb	= fuse_kill_sb_blk,
A
Alexey Dobriyan 已提交
1222
	.fs_flags	= FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
1223
};
1224
MODULE_ALIAS_FS("fuseblk");
1225

1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245
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

1246
static void fuse_inode_init_once(void *foo)
M
Miklos Szeredi 已提交
1247
{
M
Miklos Szeredi 已提交
1248
	struct inode *inode = foo;
M
Miklos Szeredi 已提交
1249

C
Christoph Lameter 已提交
1250
	inode_init_once(inode);
M
Miklos Szeredi 已提交
1251 1252 1253 1254 1255 1256
}

static int __init fuse_fs_init(void)
{
	int err;

1257
	fuse_inode_cachep = kmem_cache_create("fuse_inode",
1258 1259
					      sizeof(struct fuse_inode), 0,
					      SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT,
1260
					      fuse_inode_init_once);
1261 1262
	err = -ENOMEM;
	if (!fuse_inode_cachep)
1263 1264 1265 1266 1267 1268 1269 1270 1271
		goto out;

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

	err = register_filesystem(&fuse_fs_type);
	if (err)
		goto out3;
1272 1273

	return 0;
M
Miklos Szeredi 已提交
1274

1275
 out3:
1276
	unregister_fuseblk();
1277 1278
 out2:
	kmem_cache_destroy(fuse_inode_cachep);
1279
 out:
M
Miklos Szeredi 已提交
1280 1281 1282 1283 1284 1285
	return err;
}

static void fuse_fs_cleanup(void)
{
	unregister_filesystem(&fuse_fs_type);
1286
	unregister_fuseblk();
1287 1288 1289 1290 1291 1292

	/*
	 * Make sure all delayed rcu free inodes are flushed before we
	 * destroy cache.
	 */
	rcu_barrier();
M
Miklos Szeredi 已提交
1293 1294 1295
	kmem_cache_destroy(fuse_inode_cachep);
}

1296 1297
static struct kobject *fuse_kobj;

1298 1299 1300 1301
static int fuse_sysfs_init(void)
{
	int err;

1302
	fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
1303 1304
	if (!fuse_kobj) {
		err = -ENOMEM;
1305
		goto out_err;
1306
	}
1307

1308 1309
	err = sysfs_create_mount_point(fuse_kobj, "connections");
	if (err)
1310 1311 1312 1313 1314
		goto out_fuse_unregister;

	return 0;

 out_fuse_unregister:
1315
	kobject_put(fuse_kobj);
1316 1317 1318 1319 1320 1321
 out_err:
	return err;
}

static void fuse_sysfs_cleanup(void)
{
1322
	sysfs_remove_mount_point(fuse_kobj, "connections");
1323
	kobject_put(fuse_kobj);
1324 1325
}

M
Miklos Szeredi 已提交
1326 1327 1328 1329
static int __init fuse_init(void)
{
	int res;

M
Miklos Szeredi 已提交
1330
	printk(KERN_INFO "fuse init (API version %i.%i)\n",
M
Miklos Szeredi 已提交
1331 1332
	       FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);

1333
	INIT_LIST_HEAD(&fuse_conn_list);
M
Miklos Szeredi 已提交
1334 1335 1336 1337
	res = fuse_fs_init();
	if (res)
		goto err;

M
Miklos Szeredi 已提交
1338 1339 1340 1341
	res = fuse_dev_init();
	if (res)
		goto err_fs_cleanup;

1342 1343 1344 1345
	res = fuse_sysfs_init();
	if (res)
		goto err_dev_cleanup;

1346 1347 1348 1349
	res = fuse_ctl_init();
	if (res)
		goto err_sysfs_cleanup;

1350 1351 1352
	sanitize_global_limit(&max_user_bgreq);
	sanitize_global_limit(&max_user_congthresh);

M
Miklos Szeredi 已提交
1353 1354
	return 0;

1355 1356
 err_sysfs_cleanup:
	fuse_sysfs_cleanup();
1357 1358
 err_dev_cleanup:
	fuse_dev_cleanup();
M
Miklos Szeredi 已提交
1359 1360
 err_fs_cleanup:
	fuse_fs_cleanup();
M
Miklos Szeredi 已提交
1361 1362 1363 1364 1365 1366 1367 1368
 err:
	return res;
}

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

1369
	fuse_ctl_cleanup();
1370
	fuse_sysfs_cleanup();
M
Miklos Szeredi 已提交
1371
	fuse_fs_cleanup();
M
Miklos Szeredi 已提交
1372
	fuse_dev_cleanup();
M
Miklos Szeredi 已提交
1373 1374 1375 1376
}

module_init(fuse_init);
module_exit(fuse_exit);