dir.c 48.9 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/file.h>
#include <linux/sched.h>
#include <linux/namei.h>
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#include <linux/slab.h>
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static bool fuse_use_readdirplus(struct inode *dir, struct dir_context *ctx)
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{
	struct fuse_conn *fc = get_fuse_conn(dir);
	struct fuse_inode *fi = get_fuse_inode(dir);

	if (!fc->do_readdirplus)
		return false;
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	if (!fc->readdirplus_auto)
		return true;
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	if (test_and_clear_bit(FUSE_I_ADVISE_RDPLUS, &fi->state))
		return true;
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	if (ctx->pos == 0)
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		return true;
	return false;
}

static void fuse_advise_use_readdirplus(struct inode *dir)
{
	struct fuse_inode *fi = get_fuse_inode(dir);

	set_bit(FUSE_I_ADVISE_RDPLUS, &fi->state);
}

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#if BITS_PER_LONG >= 64
static inline void fuse_dentry_settime(struct dentry *entry, u64 time)
{
	entry->d_time = time;
}

static inline u64 fuse_dentry_time(struct dentry *entry)
{
	return entry->d_time;
}
#else
/*
 * On 32 bit archs store the high 32 bits of time in d_fsdata
 */
static void fuse_dentry_settime(struct dentry *entry, u64 time)
{
	entry->d_time = time;
	entry->d_fsdata = (void *) (unsigned long) (time >> 32);
}

static u64 fuse_dentry_time(struct dentry *entry)
{
	return (u64) entry->d_time +
		((u64) (unsigned long) entry->d_fsdata << 32);
}
#endif

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/*
 * FUSE caches dentries and attributes with separate timeout.  The
 * time in jiffies until the dentry/attributes are valid is stored in
 * dentry->d_time and fuse_inode->i_time respectively.
 */

/*
 * Calculate the time in jiffies until a dentry/attributes are valid
 */
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static u64 time_to_jiffies(unsigned long sec, unsigned long nsec)
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{
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	if (sec || nsec) {
		struct timespec ts = {sec, nsec};
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		return get_jiffies_64() + timespec_to_jiffies(&ts);
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	} else
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		return 0;
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}

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/*
 * Set dentry and possibly attribute timeouts from the lookup/mk*
 * replies
 */
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static void fuse_change_entry_timeout(struct dentry *entry,
				      struct fuse_entry_out *o)
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{
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	fuse_dentry_settime(entry,
		time_to_jiffies(o->entry_valid, o->entry_valid_nsec));
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}

static u64 attr_timeout(struct fuse_attr_out *o)
{
	return time_to_jiffies(o->attr_valid, o->attr_valid_nsec);
}

static u64 entry_attr_timeout(struct fuse_entry_out *o)
{
	return time_to_jiffies(o->attr_valid, o->attr_valid_nsec);
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}

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/*
 * Mark the attributes as stale, so that at the next call to
 * ->getattr() they will be fetched from userspace
 */
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void fuse_invalidate_attr(struct inode *inode)
{
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	get_fuse_inode(inode)->i_time = 0;
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}

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/**
 * Mark the attributes as stale due to an atime change.  Avoid the invalidate if
 * atime is not used.
 */
void fuse_invalidate_atime(struct inode *inode)
{
	if (!IS_RDONLY(inode))
		fuse_invalidate_attr(inode);
}

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/*
 * Just mark the entry as stale, so that a next attempt to look it up
 * will result in a new lookup call to userspace
 *
 * This is called when a dentry is about to become negative and the
 * timeout is unknown (unlink, rmdir, rename and in some cases
 * lookup)
 */
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void fuse_invalidate_entry_cache(struct dentry *entry)
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{
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	fuse_dentry_settime(entry, 0);
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}

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/*
 * Same as fuse_invalidate_entry_cache(), but also try to remove the
 * dentry from the hash
 */
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static void fuse_invalidate_entry(struct dentry *entry)
{
	d_invalidate(entry);
	fuse_invalidate_entry_cache(entry);
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}

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static void fuse_lookup_init(struct fuse_conn *fc, struct fuse_req *req,
			     u64 nodeid, struct qstr *name,
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			     struct fuse_entry_out *outarg)
{
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	memset(outarg, 0, sizeof(struct fuse_entry_out));
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	req->in.h.opcode = FUSE_LOOKUP;
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	req->in.h.nodeid = nodeid;
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	req->in.numargs = 1;
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	req->in.args[0].size = name->len + 1;
	req->in.args[0].value = name->name;
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	req->out.numargs = 1;
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	if (fc->minor < 9)
		req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
	else
		req->out.args[0].size = sizeof(struct fuse_entry_out);
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	req->out.args[0].value = outarg;
}

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u64 fuse_get_attr_version(struct fuse_conn *fc)
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{
	u64 curr_version;

	/*
	 * The spin lock isn't actually needed on 64bit archs, but we
	 * don't yet care too much about such optimizations.
	 */
	spin_lock(&fc->lock);
	curr_version = fc->attr_version;
	spin_unlock(&fc->lock);

	return curr_version;
}

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/*
 * Check whether the dentry is still valid
 *
 * If the entry validity timeout has expired and the dentry is
 * positive, try to redo the lookup.  If the lookup results in a
 * different inode, then let the VFS invalidate the dentry and redo
 * the lookup once more.  If the lookup results in the same inode,
 * then refresh the attributes, timeouts and mark the dentry valid.
 */
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static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
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{
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	struct inode *inode;
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	struct dentry *parent;
	struct fuse_conn *fc;
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	struct fuse_inode *fi;
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	int ret;
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	inode = ACCESS_ONCE(entry->d_inode);
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	if (inode && is_bad_inode(inode))
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		goto invalid;
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	else if (fuse_dentry_time(entry) < get_jiffies_64()) {
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		int err;
		struct fuse_entry_out outarg;
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		struct fuse_req *req;
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		struct fuse_forget_link *forget;
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		u64 attr_version;
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208
		/* For negative dentries, always do a fresh lookup */
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		if (!inode)
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			goto invalid;
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		ret = -ECHILD;
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		if (flags & LOOKUP_RCU)
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			goto out;
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		fc = get_fuse_conn(inode);
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		req = fuse_get_req_nopages(fc);
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		ret = PTR_ERR(req);
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		if (IS_ERR(req))
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			goto out;
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		forget = fuse_alloc_forget();
		if (!forget) {
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			fuse_put_request(fc, req);
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			ret = -ENOMEM;
			goto out;
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		}

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		attr_version = fuse_get_attr_version(fc);
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		parent = dget_parent(entry);
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		fuse_lookup_init(fc, req, get_node_id(parent->d_inode),
				 &entry->d_name, &outarg);
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		fuse_request_send(fc, req);
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		dput(parent);
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		err = req->out.h.error;
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		fuse_put_request(fc, req);
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		/* Zero nodeid is same as -ENOENT */
		if (!err && !outarg.nodeid)
			err = -ENOENT;
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		if (!err) {
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			fi = get_fuse_inode(inode);
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			if (outarg.nodeid != get_node_id(inode)) {
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				fuse_queue_forget(fc, forget, outarg.nodeid, 1);
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				goto invalid;
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			}
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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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		}
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		kfree(forget);
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		if (err || (outarg.attr.mode ^ inode->i_mode) & S_IFMT)
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			goto invalid;
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		fuse_change_attributes(inode, &outarg.attr,
				       entry_attr_timeout(&outarg),
				       attr_version);
		fuse_change_entry_timeout(entry, &outarg);
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	} else if (inode) {
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		fi = get_fuse_inode(inode);
		if (flags & LOOKUP_RCU) {
			if (test_bit(FUSE_I_INIT_RDPLUS, &fi->state))
				return -ECHILD;
		} else if (test_and_clear_bit(FUSE_I_INIT_RDPLUS, &fi->state)) {
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			parent = dget_parent(entry);
			fuse_advise_use_readdirplus(parent->d_inode);
			dput(parent);
		}
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	}
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	ret = 1;
out:
	return ret;

invalid:
	ret = 0;
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	if (!(flags & LOOKUP_RCU) && check_submounts_and_drop(entry) != 0)
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		ret = 1;
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	goto out;
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}

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static int invalid_nodeid(u64 nodeid)
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{
	return !nodeid || nodeid == FUSE_ROOT_ID;
}

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const struct dentry_operations fuse_dentry_operations = {
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	.d_revalidate	= fuse_dentry_revalidate,
};

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int fuse_valid_type(int m)
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{
	return S_ISREG(m) || S_ISDIR(m) || S_ISLNK(m) || S_ISCHR(m) ||
		S_ISBLK(m) || S_ISFIFO(m) || S_ISSOCK(m);
}

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int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
		     struct fuse_entry_out *outarg, struct inode **inode)
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{
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	struct fuse_conn *fc = get_fuse_conn_super(sb);
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	struct fuse_req *req;
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	struct fuse_forget_link *forget;
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	u64 attr_version;
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	int err;
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	*inode = NULL;
	err = -ENAMETOOLONG;
	if (name->len > FUSE_NAME_MAX)
		goto out;
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	req = fuse_get_req_nopages(fc);
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	err = PTR_ERR(req);
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	if (IS_ERR(req))
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		goto out;
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	forget = fuse_alloc_forget();
	err = -ENOMEM;
	if (!forget) {
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		fuse_put_request(fc, req);
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		goto out;
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	}

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	attr_version = fuse_get_attr_version(fc);
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325
	fuse_lookup_init(fc, req, nodeid, name, outarg);
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	fuse_request_send(fc, req);
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	err = req->out.h.error;
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	fuse_put_request(fc, req);
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	/* Zero nodeid is same as -ENOENT, but with valid timeout */
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	if (err || !outarg->nodeid)
		goto out_put_forget;

	err = -EIO;
	if (!outarg->nodeid)
		goto out_put_forget;
	if (!fuse_valid_type(outarg->attr.mode))
		goto out_put_forget;

	*inode = fuse_iget(sb, outarg->nodeid, outarg->generation,
			   &outarg->attr, entry_attr_timeout(outarg),
			   attr_version);
	err = -ENOMEM;
	if (!*inode) {
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		fuse_queue_forget(fc, forget, outarg->nodeid, 1);
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		goto out;
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	}
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	err = 0;

 out_put_forget:
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	kfree(forget);
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 out:
	return err;
}

static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
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				  unsigned int flags)
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{
	int err;
	struct fuse_entry_out outarg;
	struct inode *inode;
	struct dentry *newent;
	bool outarg_valid = true;

	err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name,
			       &outarg, &inode);
	if (err == -ENOENT) {
		outarg_valid = false;
		err = 0;
	}
	if (err)
		goto out_err;

	err = -EIO;
	if (inode && get_node_id(inode) == FUSE_ROOT_ID)
		goto out_iput;
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377
	newent = d_materialise_unique(entry, inode);
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	err = PTR_ERR(newent);
	if (IS_ERR(newent))
		goto out_err;
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382
	entry = newent ? newent : entry;
383
	if (outarg_valid)
384
		fuse_change_entry_timeout(entry, &outarg);
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	else
		fuse_invalidate_entry_cache(entry);
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388
	fuse_advise_use_readdirplus(dir);
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	return newent;
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 out_iput:
	iput(inode);
 out_err:
	return ERR_PTR(err);
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}

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/*
 * Atomic create+open operation
 *
 * If the filesystem doesn't support this, then fall back to separate
 * 'mknod' + 'open' requests.
 */
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static int fuse_create_open(struct inode *dir, struct dentry *entry,
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			    struct file *file, unsigned flags,
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			    umode_t mode, int *opened)
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{
	int err;
	struct inode *inode;
	struct fuse_conn *fc = get_fuse_conn(dir);
	struct fuse_req *req;
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	struct fuse_forget_link *forget;
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	struct fuse_create_in inarg;
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	struct fuse_open_out outopen;
	struct fuse_entry_out outentry;
	struct fuse_file *ff;

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	/* Userspace expects S_IFREG in create mode */
	BUG_ON((mode & S_IFMT) != S_IFREG);

420
	forget = fuse_alloc_forget();
421
	err = -ENOMEM;
422
	if (!forget)
423
		goto out_err;
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	req = fuse_get_req_nopages(fc);
426
	err = PTR_ERR(req);
427
	if (IS_ERR(req))
428
		goto out_put_forget_req;
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430
	err = -ENOMEM;
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	ff = fuse_file_alloc(fc);
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	if (!ff)
		goto out_put_request;

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	if (!fc->dont_mask)
		mode &= ~current_umask();

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	flags &= ~O_NOCTTY;
	memset(&inarg, 0, sizeof(inarg));
440
	memset(&outentry, 0, sizeof(outentry));
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	inarg.flags = flags;
	inarg.mode = mode;
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	inarg.umask = current_umask();
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	req->in.h.opcode = FUSE_CREATE;
	req->in.h.nodeid = get_node_id(dir);
	req->in.numargs = 2;
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	req->in.args[0].size = fc->minor < 12 ? sizeof(struct fuse_open_in) :
						sizeof(inarg);
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	req->in.args[0].value = &inarg;
	req->in.args[1].size = entry->d_name.len + 1;
	req->in.args[1].value = entry->d_name.name;
	req->out.numargs = 2;
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	if (fc->minor < 9)
		req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
	else
		req->out.args[0].size = sizeof(outentry);
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	req->out.args[0].value = &outentry;
	req->out.args[1].size = sizeof(outopen);
	req->out.args[1].value = &outopen;
460
	fuse_request_send(fc, req);
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	err = req->out.h.error;
462
	if (err)
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		goto out_free_ff;

	err = -EIO;
466
	if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid))
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		goto out_free_ff;

469
	fuse_put_request(fc, req);
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	ff->fh = outopen.fh;
	ff->nodeid = outentry.nodeid;
	ff->open_flags = outopen.open_flags;
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	inode = fuse_iget(dir->i_sb, outentry.nodeid, outentry.generation,
474
			  &outentry.attr, entry_attr_timeout(&outentry), 0);
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	if (!inode) {
		flags &= ~(O_CREAT | O_EXCL | O_TRUNC);
477
		fuse_sync_release(ff, flags);
478
		fuse_queue_forget(fc, forget, outentry.nodeid, 1);
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		err = -ENOMEM;
		goto out_err;
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	}
482
	kfree(forget);
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	d_instantiate(entry, inode);
484
	fuse_change_entry_timeout(entry, &outentry);
485
	fuse_invalidate_attr(dir);
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	err = finish_open(file, entry, generic_file_open, opened);
	if (err) {
488
		fuse_sync_release(ff, flags);
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	} else {
		file->private_data = fuse_file_get(ff);
		fuse_finish_open(inode, file);
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	}
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	return err;
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495
out_free_ff:
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	fuse_file_free(ff);
497
out_put_request:
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	fuse_put_request(fc, req);
499
out_put_forget_req:
500
	kfree(forget);
501
out_err:
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	return err;
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}

static int fuse_mknod(struct inode *, struct dentry *, umode_t, dev_t);
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static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
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			    struct file *file, unsigned flags,
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			    umode_t mode, int *opened)
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{
	int err;
	struct fuse_conn *fc = get_fuse_conn(dir);
	struct dentry *res = NULL;

	if (d_unhashed(entry)) {
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		res = fuse_lookup(dir, entry, 0);
516
		if (IS_ERR(res))
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			return PTR_ERR(res);
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		if (res)
			entry = res;
	}

	if (!(flags & O_CREAT) || entry->d_inode)
		goto no_open;

	/* Only creates */
527
	*opened |= FILE_CREATED;
528 529 530 531

	if (fc->no_create)
		goto mknod;

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	err = fuse_create_open(dir, entry, file, flags, mode, opened);
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	if (err == -ENOSYS) {
534 535 536 537 538
		fc->no_create = 1;
		goto mknod;
	}
out_dput:
	dput(res);
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	return err;
540 541 542

mknod:
	err = fuse_mknod(dir, entry, mode, 0);
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	if (err)
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		goto out_dput;
no_open:
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	return finish_no_open(file, res);
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}

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/*
 * Code shared between mknod, mkdir, symlink and link
 */
552 553
static int create_new_entry(struct fuse_conn *fc, struct fuse_req *req,
			    struct inode *dir, struct dentry *entry,
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			    umode_t mode)
555 556 557 558
{
	struct fuse_entry_out outarg;
	struct inode *inode;
	int err;
559
	struct fuse_forget_link *forget;
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561 562
	forget = fuse_alloc_forget();
	if (!forget) {
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		fuse_put_request(fc, req);
564
		return -ENOMEM;
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	}
566

567
	memset(&outarg, 0, sizeof(outarg));
568 569
	req->in.h.nodeid = get_node_id(dir);
	req->out.numargs = 1;
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	if (fc->minor < 9)
		req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
	else
		req->out.args[0].size = sizeof(outarg);
574
	req->out.args[0].value = &outarg;
575
	fuse_request_send(fc, req);
576
	err = req->out.h.error;
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	fuse_put_request(fc, req);
	if (err)
		goto out_put_forget_req;

581 582
	err = -EIO;
	if (invalid_nodeid(outarg.nodeid))
M
Miklos Szeredi 已提交
583
		goto out_put_forget_req;
584 585

	if ((outarg.attr.mode ^ mode) & S_IFMT)
M
Miklos Szeredi 已提交
586
		goto out_put_forget_req;
587

588
	inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation,
589
			  &outarg.attr, entry_attr_timeout(&outarg), 0);
590
	if (!inode) {
591
		fuse_queue_forget(fc, forget, outarg.nodeid, 1);
592 593
		return -ENOMEM;
	}
594
	kfree(forget);
595

596 597 598
	err = d_instantiate_no_diralias(entry, inode);
	if (err)
		return err;
599

600
	fuse_change_entry_timeout(entry, &outarg);
601 602
	fuse_invalidate_attr(dir);
	return 0;
603

M
Miklos Szeredi 已提交
604
 out_put_forget_req:
605
	kfree(forget);
606
	return err;
607 608
}

A
Al Viro 已提交
609
static int fuse_mknod(struct inode *dir, struct dentry *entry, umode_t mode,
610 611 612 613
		      dev_t rdev)
{
	struct fuse_mknod_in inarg;
	struct fuse_conn *fc = get_fuse_conn(dir);
M
Maxim Patlasov 已提交
614
	struct fuse_req *req = fuse_get_req_nopages(fc);
615 616
	if (IS_ERR(req))
		return PTR_ERR(req);
617

618 619 620
	if (!fc->dont_mask)
		mode &= ~current_umask();

621 622 623
	memset(&inarg, 0, sizeof(inarg));
	inarg.mode = mode;
	inarg.rdev = new_encode_dev(rdev);
624
	inarg.umask = current_umask();
625 626
	req->in.h.opcode = FUSE_MKNOD;
	req->in.numargs = 2;
627 628
	req->in.args[0].size = fc->minor < 12 ? FUSE_COMPAT_MKNOD_IN_SIZE :
						sizeof(inarg);
629 630 631 632 633 634
	req->in.args[0].value = &inarg;
	req->in.args[1].size = entry->d_name.len + 1;
	req->in.args[1].value = entry->d_name.name;
	return create_new_entry(fc, req, dir, entry, mode);
}

A
Al Viro 已提交
635
static int fuse_create(struct inode *dir, struct dentry *entry, umode_t mode,
A
Al Viro 已提交
636
		       bool excl)
637 638 639 640
{
	return fuse_mknod(dir, entry, mode, 0);
}

641
static int fuse_mkdir(struct inode *dir, struct dentry *entry, umode_t mode)
642 643 644
{
	struct fuse_mkdir_in inarg;
	struct fuse_conn *fc = get_fuse_conn(dir);
M
Maxim Patlasov 已提交
645
	struct fuse_req *req = fuse_get_req_nopages(fc);
646 647
	if (IS_ERR(req))
		return PTR_ERR(req);
648

649 650 651
	if (!fc->dont_mask)
		mode &= ~current_umask();

652 653
	memset(&inarg, 0, sizeof(inarg));
	inarg.mode = mode;
654
	inarg.umask = current_umask();
655 656 657 658 659 660 661 662 663 664 665 666 667 668
	req->in.h.opcode = FUSE_MKDIR;
	req->in.numargs = 2;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->in.args[1].size = entry->d_name.len + 1;
	req->in.args[1].value = entry->d_name.name;
	return create_new_entry(fc, req, dir, entry, S_IFDIR);
}

static int fuse_symlink(struct inode *dir, struct dentry *entry,
			const char *link)
{
	struct fuse_conn *fc = get_fuse_conn(dir);
	unsigned len = strlen(link) + 1;
M
Maxim Patlasov 已提交
669
	struct fuse_req *req = fuse_get_req_nopages(fc);
670 671
	if (IS_ERR(req))
		return PTR_ERR(req);
672 673 674 675 676 677 678 679 680 681 682 683 684 685

	req->in.h.opcode = FUSE_SYMLINK;
	req->in.numargs = 2;
	req->in.args[0].size = entry->d_name.len + 1;
	req->in.args[0].value = entry->d_name.name;
	req->in.args[1].size = len;
	req->in.args[1].value = link;
	return create_new_entry(fc, req, dir, entry, S_IFLNK);
}

static int fuse_unlink(struct inode *dir, struct dentry *entry)
{
	int err;
	struct fuse_conn *fc = get_fuse_conn(dir);
M
Maxim Patlasov 已提交
686
	struct fuse_req *req = fuse_get_req_nopages(fc);
687 688
	if (IS_ERR(req))
		return PTR_ERR(req);
689 690 691 692 693 694

	req->in.h.opcode = FUSE_UNLINK;
	req->in.h.nodeid = get_node_id(dir);
	req->in.numargs = 1;
	req->in.args[0].size = entry->d_name.len + 1;
	req->in.args[0].value = entry->d_name.name;
695
	fuse_request_send(fc, req);
696 697 698 699
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (!err) {
		struct inode *inode = entry->d_inode;
M
Miklos Szeredi 已提交
700
		struct fuse_inode *fi = get_fuse_inode(inode);
701

M
Miklos Szeredi 已提交
702 703
		spin_lock(&fc->lock);
		fi->attr_version = ++fc->attr_version;
704 705 706 707 708 709 710 711
		/*
		 * If i_nlink == 0 then unlink doesn't make sense, yet this can
		 * happen if userspace filesystem is careless.  It would be
		 * difficult to enforce correct nlink usage so just ignore this
		 * condition here
		 */
		if (inode->i_nlink > 0)
			drop_nlink(inode);
M
Miklos Szeredi 已提交
712
		spin_unlock(&fc->lock);
713 714
		fuse_invalidate_attr(inode);
		fuse_invalidate_attr(dir);
715
		fuse_invalidate_entry_cache(entry);
716 717 718 719 720 721 722 723 724
	} else if (err == -EINTR)
		fuse_invalidate_entry(entry);
	return err;
}

static int fuse_rmdir(struct inode *dir, struct dentry *entry)
{
	int err;
	struct fuse_conn *fc = get_fuse_conn(dir);
M
Maxim Patlasov 已提交
725
	struct fuse_req *req = fuse_get_req_nopages(fc);
726 727
	if (IS_ERR(req))
		return PTR_ERR(req);
728 729 730 731 732 733

	req->in.h.opcode = FUSE_RMDIR;
	req->in.h.nodeid = get_node_id(dir);
	req->in.numargs = 1;
	req->in.args[0].size = entry->d_name.len + 1;
	req->in.args[0].value = entry->d_name.name;
734
	fuse_request_send(fc, req);
735 736 737
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (!err) {
738
		clear_nlink(entry->d_inode);
739
		fuse_invalidate_attr(dir);
740
		fuse_invalidate_entry_cache(entry);
741 742 743 744 745 746 747 748 749 750 751
	} else if (err == -EINTR)
		fuse_invalidate_entry(entry);
	return err;
}

static int fuse_rename(struct inode *olddir, struct dentry *oldent,
		       struct inode *newdir, struct dentry *newent)
{
	int err;
	struct fuse_rename_in inarg;
	struct fuse_conn *fc = get_fuse_conn(olddir);
M
Maxim Patlasov 已提交
752
	struct fuse_req *req = fuse_get_req_nopages(fc);
753

754 755
	if (IS_ERR(req))
		return PTR_ERR(req);
756 757 758 759 760 761 762 763 764 765 766 767

	memset(&inarg, 0, sizeof(inarg));
	inarg.newdir = get_node_id(newdir);
	req->in.h.opcode = FUSE_RENAME;
	req->in.h.nodeid = get_node_id(olddir);
	req->in.numargs = 3;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->in.args[1].size = oldent->d_name.len + 1;
	req->in.args[1].value = oldent->d_name.name;
	req->in.args[2].size = newent->d_name.len + 1;
	req->in.args[2].value = newent->d_name.name;
768
	fuse_request_send(fc, req);
769 770 771
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (!err) {
772 773 774
		/* ctime changes */
		fuse_invalidate_attr(oldent->d_inode);

775 776 777
		fuse_invalidate_attr(olddir);
		if (olddir != newdir)
			fuse_invalidate_attr(newdir);
778 779

		/* newent will end up negative */
M
Miklos Szeredi 已提交
780 781
		if (newent->d_inode) {
			fuse_invalidate_attr(newent->d_inode);
782
			fuse_invalidate_entry_cache(newent);
M
Miklos Szeredi 已提交
783
		}
784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804
	} else if (err == -EINTR) {
		/* If request was interrupted, DEITY only knows if the
		   rename actually took place.  If the invalidation
		   fails (e.g. some process has CWD under the renamed
		   directory), then there can be inconsistency between
		   the dcache and the real filesystem.  Tough luck. */
		fuse_invalidate_entry(oldent);
		if (newent->d_inode)
			fuse_invalidate_entry(newent);
	}

	return err;
}

static int fuse_link(struct dentry *entry, struct inode *newdir,
		     struct dentry *newent)
{
	int err;
	struct fuse_link_in inarg;
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
M
Maxim Patlasov 已提交
805
	struct fuse_req *req = fuse_get_req_nopages(fc);
806 807
	if (IS_ERR(req))
		return PTR_ERR(req);
808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823

	memset(&inarg, 0, sizeof(inarg));
	inarg.oldnodeid = get_node_id(inode);
	req->in.h.opcode = FUSE_LINK;
	req->in.numargs = 2;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->in.args[1].size = newent->d_name.len + 1;
	req->in.args[1].value = newent->d_name.name;
	err = create_new_entry(fc, req, newdir, newent, inode->i_mode);
	/* Contrary to "normal" filesystems it can happen that link
	   makes two "logical" inodes point to the same "physical"
	   inode.  We invalidate the attributes of the old one, so it
	   will reflect changes in the backing inode (link count,
	   etc.)
	*/
M
Miklos Szeredi 已提交
824 825 826 827 828 829 830
	if (!err) {
		struct fuse_inode *fi = get_fuse_inode(inode);

		spin_lock(&fc->lock);
		fi->attr_version = ++fc->attr_version;
		inc_nlink(inode);
		spin_unlock(&fc->lock);
831
		fuse_invalidate_attr(inode);
M
Miklos Szeredi 已提交
832 833 834
	} else if (err == -EINTR) {
		fuse_invalidate_attr(inode);
	}
835 836 837
	return err;
}

838 839 840
static void fuse_fillattr(struct inode *inode, struct fuse_attr *attr,
			  struct kstat *stat)
{
M
Miklos Szeredi 已提交
841
	unsigned int blkbits;
P
Pavel Emelyanov 已提交
842 843 844
	struct fuse_conn *fc = get_fuse_conn(inode);

	/* see the comment in fuse_change_attributes() */
M
Maxim Patlasov 已提交
845
	if (fc->writeback_cache && S_ISREG(inode->i_mode)) {
P
Pavel Emelyanov 已提交
846
		attr->size = i_size_read(inode);
M
Maxim Patlasov 已提交
847 848 849
		attr->mtime = inode->i_mtime.tv_sec;
		attr->mtimensec = inode->i_mtime.tv_nsec;
	}
M
Miklos Szeredi 已提交
850

851 852 853 854
	stat->dev = inode->i_sb->s_dev;
	stat->ino = attr->ino;
	stat->mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
	stat->nlink = attr->nlink;
855 856
	stat->uid = make_kuid(&init_user_ns, attr->uid);
	stat->gid = make_kgid(&init_user_ns, attr->gid);
857 858 859 860 861 862 863 864 865
	stat->rdev = inode->i_rdev;
	stat->atime.tv_sec = attr->atime;
	stat->atime.tv_nsec = attr->atimensec;
	stat->mtime.tv_sec = attr->mtime;
	stat->mtime.tv_nsec = attr->mtimensec;
	stat->ctime.tv_sec = attr->ctime;
	stat->ctime.tv_nsec = attr->ctimensec;
	stat->size = attr->size;
	stat->blocks = attr->blocks;
M
Miklos Szeredi 已提交
866 867 868 869 870 871 872

	if (attr->blksize != 0)
		blkbits = ilog2(attr->blksize);
	else
		blkbits = inode->i_sb->s_blocksize_bits;

	stat->blksize = 1 << blkbits;
873 874
}

875 876
static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
			   struct file *file)
877 878
{
	int err;
879 880
	struct fuse_getattr_in inarg;
	struct fuse_attr_out outarg;
881
	struct fuse_conn *fc = get_fuse_conn(inode);
882 883 884
	struct fuse_req *req;
	u64 attr_version;

M
Maxim Patlasov 已提交
885
	req = fuse_get_req_nopages(fc);
886 887
	if (IS_ERR(req))
		return PTR_ERR(req);
888

889
	attr_version = fuse_get_attr_version(fc);
890

891
	memset(&inarg, 0, sizeof(inarg));
892
	memset(&outarg, 0, sizeof(outarg));
893 894 895 896 897 898 899
	/* Directories have separate file-handle space */
	if (file && S_ISREG(inode->i_mode)) {
		struct fuse_file *ff = file->private_data;

		inarg.getattr_flags |= FUSE_GETATTR_FH;
		inarg.fh = ff->fh;
	}
900 901
	req->in.h.opcode = FUSE_GETATTR;
	req->in.h.nodeid = get_node_id(inode);
902 903 904
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
905
	req->out.numargs = 1;
906 907 908 909
	if (fc->minor < 9)
		req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
	else
		req->out.args[0].size = sizeof(outarg);
910
	req->out.args[0].value = &outarg;
911
	fuse_request_send(fc, req);
912 913 914
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (!err) {
915
		if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) {
916 917 918
			make_bad_inode(inode);
			err = -EIO;
		} else {
919 920
			fuse_change_attributes(inode, &outarg.attr,
					       attr_timeout(&outarg),
921 922
					       attr_version);
			if (stat)
923
				fuse_fillattr(inode, &outarg.attr, stat);
924 925 926 927 928
		}
	}
	return err;
}

M
Miklos Szeredi 已提交
929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944
int fuse_update_attributes(struct inode *inode, struct kstat *stat,
			   struct file *file, bool *refreshed)
{
	struct fuse_inode *fi = get_fuse_inode(inode);
	int err;
	bool r;

	if (fi->i_time < get_jiffies_64()) {
		r = true;
		err = fuse_do_getattr(inode, stat, file);
	} else {
		r = false;
		err = 0;
		if (stat) {
			generic_fillattr(inode, stat);
			stat->mode = fi->orig_i_mode;
945
			stat->ino = fi->orig_ino;
M
Miklos Szeredi 已提交
946 947 948 949 950 951 952 953 954
		}
	}

	if (refreshed != NULL)
		*refreshed = r;

	return err;
}

J
John Muir 已提交
955
int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
956
			     u64 child_nodeid, struct qstr *name)
J
John Muir 已提交
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
{
	int err = -ENOTDIR;
	struct inode *parent;
	struct dentry *dir;
	struct dentry *entry;

	parent = ilookup5(sb, parent_nodeid, fuse_inode_eq, &parent_nodeid);
	if (!parent)
		return -ENOENT;

	mutex_lock(&parent->i_mutex);
	if (!S_ISDIR(parent->i_mode))
		goto unlock;

	err = -ENOENT;
	dir = d_find_alias(parent);
	if (!dir)
		goto unlock;

	entry = d_lookup(dir, name);
	dput(dir);
	if (!entry)
		goto unlock;

	fuse_invalidate_attr(parent);
	fuse_invalidate_entry(entry);
983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011

	if (child_nodeid != 0 && entry->d_inode) {
		mutex_lock(&entry->d_inode->i_mutex);
		if (get_node_id(entry->d_inode) != child_nodeid) {
			err = -ENOENT;
			goto badentry;
		}
		if (d_mountpoint(entry)) {
			err = -EBUSY;
			goto badentry;
		}
		if (S_ISDIR(entry->d_inode->i_mode)) {
			shrink_dcache_parent(entry);
			if (!simple_empty(entry)) {
				err = -ENOTEMPTY;
				goto badentry;
			}
			entry->d_inode->i_flags |= S_DEAD;
		}
		dont_mount(entry);
		clear_nlink(entry->d_inode);
		err = 0;
 badentry:
		mutex_unlock(&entry->d_inode->i_mutex);
		if (!err)
			d_delete(entry);
	} else {
		err = 0;
	}
J
John Muir 已提交
1012 1013 1014 1015 1016 1017 1018 1019
	dput(entry);

 unlock:
	mutex_unlock(&parent->i_mutex);
	iput(parent);
	return err;
}

1020 1021
/*
 * Calling into a user-controlled filesystem gives the filesystem
1022
 * daemon ptrace-like capabilities over the current process.  This
1023 1024 1025 1026 1027 1028 1029 1030 1031 1032
 * means, that the filesystem daemon is able to record the exact
 * filesystem operations performed, and can also control the behavior
 * of the requester process in otherwise impossible ways.  For example
 * it can delay the operation for arbitrary length of time allowing
 * DoS against the requester.
 *
 * For this reason only those processes can call into the filesystem,
 * for which the owner of the mount has ptrace privilege.  This
 * excludes processes started by other users, suid or sgid processes.
 */
1033
int fuse_allow_current_process(struct fuse_conn *fc)
1034
{
1035
	const struct cred *cred;
1036

1037
	if (fc->flags & FUSE_ALLOW_OTHER)
1038 1039
		return 1;

1040
	cred = current_cred();
1041 1042 1043 1044 1045 1046
	if (uid_eq(cred->euid, fc->user_id) &&
	    uid_eq(cred->suid, fc->user_id) &&
	    uid_eq(cred->uid,  fc->user_id) &&
	    gid_eq(cred->egid, fc->group_id) &&
	    gid_eq(cred->sgid, fc->group_id) &&
	    gid_eq(cred->gid,  fc->group_id))
1047
		return 1;
1048

1049
	return 0;
1050 1051
}

M
Miklos Szeredi 已提交
1052 1053 1054 1055 1056 1057 1058
static int fuse_access(struct inode *inode, int mask)
{
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	struct fuse_access_in inarg;
	int err;

1059 1060
	BUG_ON(mask & MAY_NOT_BLOCK);

M
Miklos Szeredi 已提交
1061 1062 1063
	if (fc->no_access)
		return 0;

M
Maxim Patlasov 已提交
1064
	req = fuse_get_req_nopages(fc);
1065 1066
	if (IS_ERR(req))
		return PTR_ERR(req);
M
Miklos Szeredi 已提交
1067 1068

	memset(&inarg, 0, sizeof(inarg));
1069
	inarg.mask = mask & (MAY_READ | MAY_WRITE | MAY_EXEC);
M
Miklos Szeredi 已提交
1070 1071 1072 1073 1074
	req->in.h.opcode = FUSE_ACCESS;
	req->in.h.nodeid = get_node_id(inode);
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
1075
	fuse_request_send(fc, req);
M
Miklos Szeredi 已提交
1076 1077 1078 1079 1080 1081 1082 1083 1084
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (err == -ENOSYS) {
		fc->no_access = 1;
		err = 0;
	}
	return err;
}

1085
static int fuse_perm_getattr(struct inode *inode, int mask)
1086
{
1087
	if (mask & MAY_NOT_BLOCK)
1088 1089 1090 1091 1092
		return -ECHILD;

	return fuse_do_getattr(inode, NULL, NULL);
}

1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105
/*
 * Check permission.  The two basic access models of FUSE are:
 *
 * 1) Local access checking ('default_permissions' mount option) based
 * on file mode.  This is the plain old disk filesystem permission
 * modell.
 *
 * 2) "Remote" access checking, where server is responsible for
 * checking permission in each inode operation.  An exception to this
 * is if ->permission() was invoked from sys_access() in which case an
 * access request is sent.  Execute permission is still checked
 * locally based on file mode.
 */
1106
static int fuse_permission(struct inode *inode, int mask)
1107 1108
{
	struct fuse_conn *fc = get_fuse_conn(inode);
1109 1110
	bool refreshed = false;
	int err = 0;
1111

1112
	if (!fuse_allow_current_process(fc))
1113
		return -EACCES;
1114 1115

	/*
1116
	 * If attributes are needed, refresh them before proceeding
1117
	 */
1118 1119
	if ((fc->flags & FUSE_DEFAULT_PERMISSIONS) ||
	    ((mask & MAY_EXEC) && S_ISREG(inode->i_mode))) {
1120 1121 1122 1123 1124
		struct fuse_inode *fi = get_fuse_inode(inode);

		if (fi->i_time < get_jiffies_64()) {
			refreshed = true;

1125
			err = fuse_perm_getattr(inode, mask);
1126 1127 1128
			if (err)
				return err;
		}
1129 1130 1131
	}

	if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
1132
		err = generic_permission(inode, mask);
M
Miklos Szeredi 已提交
1133 1134 1135 1136

		/* If permission is denied, try to refresh file
		   attributes.  This is also needed, because the root
		   node will at first have no permissions */
1137
		if (err == -EACCES && !refreshed) {
1138
			err = fuse_perm_getattr(inode, mask);
M
Miklos Szeredi 已提交
1139
			if (!err)
1140
				err = generic_permission(inode, mask);
M
Miklos Szeredi 已提交
1141 1142
		}

1143 1144 1145 1146
		/* Note: the opposite of the above test does not
		   exist.  So if permissions are revoked this won't be
		   noticed immediately, only after the attribute
		   timeout has expired */
E
Eric Paris 已提交
1147
	} else if (mask & (MAY_ACCESS | MAY_CHDIR)) {
1148 1149 1150 1151 1152 1153
		err = fuse_access(inode, mask);
	} else if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) {
		if (!(inode->i_mode & S_IXUGO)) {
			if (refreshed)
				return -EACCES;

1154
			err = fuse_perm_getattr(inode, mask);
1155 1156 1157
			if (!err && !(inode->i_mode & S_IXUGO))
				return -EACCES;
		}
1158
	}
1159
	return err;
1160 1161 1162
}

static int parse_dirfile(char *buf, size_t nbytes, struct file *file,
A
Al Viro 已提交
1163
			 struct dir_context *ctx)
1164 1165 1166 1167 1168 1169 1170 1171
{
	while (nbytes >= FUSE_NAME_OFFSET) {
		struct fuse_dirent *dirent = (struct fuse_dirent *) buf;
		size_t reclen = FUSE_DIRENT_SIZE(dirent);
		if (!dirent->namelen || dirent->namelen > FUSE_NAME_MAX)
			return -EIO;
		if (reclen > nbytes)
			break;
1172 1173
		if (memchr(dirent->name, '/', dirent->namelen) != NULL)
			return -EIO;
1174

A
Al Viro 已提交
1175 1176
		if (!dir_emit(ctx, dirent->name, dirent->namelen,
			       dirent->ino, dirent->type))
1177 1178 1179 1180
			break;

		buf += reclen;
		nbytes -= reclen;
A
Al Viro 已提交
1181
		ctx->pos = dirent->off;
1182 1183 1184 1185 1186
	}

	return 0;
}

1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222
static int fuse_direntplus_link(struct file *file,
				struct fuse_direntplus *direntplus,
				u64 attr_version)
{
	int err;
	struct fuse_entry_out *o = &direntplus->entry_out;
	struct fuse_dirent *dirent = &direntplus->dirent;
	struct dentry *parent = file->f_path.dentry;
	struct qstr name = QSTR_INIT(dirent->name, dirent->namelen);
	struct dentry *dentry;
	struct dentry *alias;
	struct inode *dir = parent->d_inode;
	struct fuse_conn *fc;
	struct inode *inode;

	if (!o->nodeid) {
		/*
		 * Unlike in the case of fuse_lookup, zero nodeid does not mean
		 * ENOENT. Instead, it only means the userspace filesystem did
		 * not want to return attributes/handle for this entry.
		 *
		 * So do nothing.
		 */
		return 0;
	}

	if (name.name[0] == '.') {
		/*
		 * We could potentially refresh the attributes of the directory
		 * and its parent?
		 */
		if (name.len == 1)
			return 0;
		if (name.name[1] == '.' && name.len == 2)
			return 0;
	}
1223 1224 1225 1226 1227 1228

	if (invalid_nodeid(o->nodeid))
		return -EIO;
	if (!fuse_valid_type(o->attr.mode))
		return -EIO;

1229 1230 1231 1232
	fc = get_fuse_conn(dir);

	name.hash = full_name_hash(name.name, name.len);
	dentry = d_lookup(parent, &name);
1233
	if (dentry) {
1234
		inode = dentry->d_inode;
1235 1236
		if (!inode) {
			d_drop(dentry);
1237 1238
		} else if (get_node_id(inode) != o->nodeid ||
			   ((o->attr.mode ^ inode->i_mode) & S_IFMT)) {
1239 1240 1241
			err = d_invalidate(dentry);
			if (err)
				goto out;
1242 1243 1244
		} else if (is_bad_inode(inode)) {
			err = -EIO;
			goto out;
1245
		} else {
1246 1247 1248 1249 1250 1251
			struct fuse_inode *fi;
			fi = get_fuse_inode(inode);
			spin_lock(&fc->lock);
			fi->nlookup++;
			spin_unlock(&fc->lock);

1252 1253 1254 1255
			fuse_change_attributes(inode, &o->attr,
					       entry_attr_timeout(o),
					       attr_version);

1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274
			/*
			 * The other branch to 'found' comes via fuse_iget()
			 * which bumps nlookup inside
			 */
			goto found;
		}
		dput(dentry);
	}

	dentry = d_alloc(parent, &name);
	err = -ENOMEM;
	if (!dentry)
		goto out;

	inode = fuse_iget(dir->i_sb, o->nodeid, o->generation,
			  &o->attr, entry_attr_timeout(o), attr_version);
	if (!inode)
		goto out;

1275
	alias = d_materialise_unique(dentry, inode);
1276 1277 1278
	err = PTR_ERR(alias);
	if (IS_ERR(alias))
		goto out;
1279

1280 1281 1282 1283 1284 1285
	if (alias) {
		dput(dentry);
		dentry = alias;
	}

found:
M
Miklos Szeredi 已提交
1286 1287
	if (fc->readdirplus_auto)
		set_bit(FUSE_I_INIT_RDPLUS, &get_fuse_inode(inode)->state);
1288 1289 1290 1291
	fuse_change_entry_timeout(dentry, o);

	err = 0;
out:
M
Miklos Szeredi 已提交
1292
	dput(dentry);
1293 1294 1295 1296
	return err;
}

static int parse_dirplusfile(char *buf, size_t nbytes, struct file *file,
A
Al Viro 已提交
1297
			     struct dir_context *ctx, u64 attr_version)
1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313
{
	struct fuse_direntplus *direntplus;
	struct fuse_dirent *dirent;
	size_t reclen;
	int over = 0;
	int ret;

	while (nbytes >= FUSE_NAME_OFFSET_DIRENTPLUS) {
		direntplus = (struct fuse_direntplus *) buf;
		dirent = &direntplus->dirent;
		reclen = FUSE_DIRENTPLUS_SIZE(direntplus);

		if (!dirent->namelen || dirent->namelen > FUSE_NAME_MAX)
			return -EIO;
		if (reclen > nbytes)
			break;
1314 1315
		if (memchr(dirent->name, '/', dirent->namelen) != NULL)
			return -EIO;
1316 1317 1318 1319 1320 1321 1322 1323

		if (!over) {
			/* We fill entries into dstbuf only as much as
			   it can hold. But we still continue iterating
			   over remaining entries to link them. If not,
			   we need to send a FORGET for each of those
			   which we did not link.
			*/
A
Al Viro 已提交
1324 1325 1326
			over = !dir_emit(ctx, dirent->name, dirent->namelen,
				       dirent->ino, dirent->type);
			ctx->pos = dirent->off;
1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339
		}

		buf += reclen;
		nbytes -= reclen;

		ret = fuse_direntplus_link(file, direntplus, attr_version);
		if (ret)
			fuse_force_forget(file, direntplus->entry_out.nodeid);
	}

	return 0;
}

A
Al Viro 已提交
1340
static int fuse_readdir(struct file *file, struct dir_context *ctx)
1341
{
1342
	int plus, err;
1343 1344
	size_t nbytes;
	struct page *page;
A
Al Viro 已提交
1345
	struct inode *inode = file_inode(file);
1346
	struct fuse_conn *fc = get_fuse_conn(inode);
1347
	struct fuse_req *req;
1348
	u64 attr_version = 0;
1349 1350 1351 1352

	if (is_bad_inode(inode))
		return -EIO;

M
Maxim Patlasov 已提交
1353
	req = fuse_get_req(fc, 1);
1354 1355
	if (IS_ERR(req))
		return PTR_ERR(req);
1356

1357 1358 1359 1360 1361
	page = alloc_page(GFP_KERNEL);
	if (!page) {
		fuse_put_request(fc, req);
		return -ENOMEM;
	}
1362

A
Al Viro 已提交
1363
	plus = fuse_use_readdirplus(inode, ctx);
1364
	req->out.argpages = 1;
1365 1366
	req->num_pages = 1;
	req->pages[0] = page;
1367
	req->page_descs[0].length = PAGE_SIZE;
1368
	if (plus) {
1369
		attr_version = fuse_get_attr_version(fc);
A
Al Viro 已提交
1370
		fuse_read_fill(req, file, ctx->pos, PAGE_SIZE,
1371 1372
			       FUSE_READDIRPLUS);
	} else {
A
Al Viro 已提交
1373
		fuse_read_fill(req, file, ctx->pos, PAGE_SIZE,
1374 1375
			       FUSE_READDIR);
	}
1376
	fuse_request_send(fc, req);
1377
	nbytes = req->out.args[0].size;
1378 1379
	err = req->out.h.error;
	fuse_put_request(fc, req);
1380
	if (!err) {
1381
		if (plus) {
1382
			err = parse_dirplusfile(page_address(page), nbytes,
A
Al Viro 已提交
1383
						file, ctx,
1384 1385 1386
						attr_version);
		} else {
			err = parse_dirfile(page_address(page), nbytes, file,
A
Al Viro 已提交
1387
					    ctx);
1388 1389
		}
	}
1390

1391
	__free_page(page);
1392
	fuse_invalidate_atime(inode);
1393
	return err;
1394 1395 1396 1397 1398 1399
}

static char *read_link(struct dentry *dentry)
{
	struct inode *inode = dentry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
M
Maxim Patlasov 已提交
1400
	struct fuse_req *req = fuse_get_req_nopages(fc);
1401 1402
	char *link;

1403
	if (IS_ERR(req))
1404
		return ERR_CAST(req);
1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416

	link = (char *) __get_free_page(GFP_KERNEL);
	if (!link) {
		link = ERR_PTR(-ENOMEM);
		goto out;
	}
	req->in.h.opcode = FUSE_READLINK;
	req->in.h.nodeid = get_node_id(inode);
	req->out.argvar = 1;
	req->out.numargs = 1;
	req->out.args[0].size = PAGE_SIZE - 1;
	req->out.args[0].value = link;
1417
	fuse_request_send(fc, req);
1418 1419 1420 1421 1422 1423 1424
	if (req->out.h.error) {
		free_page((unsigned long) link);
		link = ERR_PTR(req->out.h.error);
	} else
		link[req->out.args[0].size] = '\0';
 out:
	fuse_put_request(fc, req);
1425
	fuse_invalidate_atime(inode);
1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447
	return link;
}

static void free_link(char *link)
{
	if (!IS_ERR(link))
		free_page((unsigned long) link);
}

static void *fuse_follow_link(struct dentry *dentry, struct nameidata *nd)
{
	nd_set_link(nd, read_link(dentry));
	return NULL;
}

static void fuse_put_link(struct dentry *dentry, struct nameidata *nd, void *c)
{
	free_link(nd_get_link(nd));
}

static int fuse_dir_open(struct inode *inode, struct file *file)
{
1448
	return fuse_open_common(inode, file, true);
1449 1450 1451 1452
}

static int fuse_dir_release(struct inode *inode, struct file *file)
{
1453 1454 1455
	fuse_release_common(file, FUSE_RELEASEDIR);

	return 0;
1456 1457
}

1458 1459
static int fuse_dir_fsync(struct file *file, loff_t start, loff_t end,
			  int datasync)
1460
{
1461
	return fuse_fsync_common(file, start, end, datasync, 1);
1462 1463
}

1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487
static long fuse_dir_ioctl(struct file *file, unsigned int cmd,
			    unsigned long arg)
{
	struct fuse_conn *fc = get_fuse_conn(file->f_mapping->host);

	/* FUSE_IOCTL_DIR only supported for API version >= 7.18 */
	if (fc->minor < 18)
		return -ENOTTY;

	return fuse_ioctl_common(file, cmd, arg, FUSE_IOCTL_DIR);
}

static long fuse_dir_compat_ioctl(struct file *file, unsigned int cmd,
				   unsigned long arg)
{
	struct fuse_conn *fc = get_fuse_conn(file->f_mapping->host);

	if (fc->minor < 18)
		return -ENOTTY;

	return fuse_ioctl_common(file, cmd, arg,
				 FUSE_IOCTL_COMPAT | FUSE_IOCTL_DIR);
}

M
Maxim Patlasov 已提交
1488
static bool update_mtime(unsigned ivalid, bool trust_local_mtime)
M
Miklos Szeredi 已提交
1489 1490 1491 1492 1493
{
	/* Always update if mtime is explicitly set  */
	if (ivalid & ATTR_MTIME_SET)
		return true;

M
Maxim Patlasov 已提交
1494 1495 1496 1497
	/* Or if kernel i_mtime is the official one */
	if (trust_local_mtime)
		return true;

M
Miklos Szeredi 已提交
1498 1499 1500 1501 1502 1503 1504 1505
	/* If it's an open(O_TRUNC) or an ftruncate(), don't update */
	if ((ivalid & ATTR_SIZE) && (ivalid & (ATTR_OPEN | ATTR_FILE)))
		return false;

	/* In all other cases update */
	return true;
}

M
Maxim Patlasov 已提交
1506 1507
static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg,
			   bool trust_local_mtime)
1508 1509 1510 1511
{
	unsigned ivalid = iattr->ia_valid;

	if (ivalid & ATTR_MODE)
1512
		arg->valid |= FATTR_MODE,   arg->mode = iattr->ia_mode;
1513
	if (ivalid & ATTR_UID)
1514
		arg->valid |= FATTR_UID,    arg->uid = from_kuid(&init_user_ns, iattr->ia_uid);
1515
	if (ivalid & ATTR_GID)
1516
		arg->valid |= FATTR_GID,    arg->gid = from_kgid(&init_user_ns, iattr->ia_gid);
1517
	if (ivalid & ATTR_SIZE)
1518
		arg->valid |= FATTR_SIZE,   arg->size = iattr->ia_size;
M
Miklos Szeredi 已提交
1519 1520
	if (ivalid & ATTR_ATIME) {
		arg->valid |= FATTR_ATIME;
1521
		arg->atime = iattr->ia_atime.tv_sec;
M
Miklos Szeredi 已提交
1522 1523 1524 1525
		arg->atimensec = iattr->ia_atime.tv_nsec;
		if (!(ivalid & ATTR_ATIME_SET))
			arg->valid |= FATTR_ATIME_NOW;
	}
M
Maxim Patlasov 已提交
1526
	if ((ivalid & ATTR_MTIME) && update_mtime(ivalid, trust_local_mtime)) {
M
Miklos Szeredi 已提交
1527
		arg->valid |= FATTR_MTIME;
1528
		arg->mtime = iattr->ia_mtime.tv_sec;
M
Miklos Szeredi 已提交
1529
		arg->mtimensec = iattr->ia_mtime.tv_nsec;
M
Maxim Patlasov 已提交
1530
		if (!(ivalid & ATTR_MTIME_SET) && !trust_local_mtime)
M
Miklos Szeredi 已提交
1531
			arg->valid |= FATTR_MTIME_NOW;
1532
	}
1533 1534
}

M
Miklos Szeredi 已提交
1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578
/*
 * Prevent concurrent writepages on inode
 *
 * This is done by adding a negative bias to the inode write counter
 * and waiting for all pending writes to finish.
 */
void fuse_set_nowrite(struct inode *inode)
{
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_inode *fi = get_fuse_inode(inode);

	BUG_ON(!mutex_is_locked(&inode->i_mutex));

	spin_lock(&fc->lock);
	BUG_ON(fi->writectr < 0);
	fi->writectr += FUSE_NOWRITE;
	spin_unlock(&fc->lock);
	wait_event(fi->page_waitq, fi->writectr == FUSE_NOWRITE);
}

/*
 * Allow writepages on inode
 *
 * Remove the bias from the writecounter and send any queued
 * writepages.
 */
static void __fuse_release_nowrite(struct inode *inode)
{
	struct fuse_inode *fi = get_fuse_inode(inode);

	BUG_ON(fi->writectr != FUSE_NOWRITE);
	fi->writectr = 0;
	fuse_flush_writepages(inode);
}

void fuse_release_nowrite(struct inode *inode)
{
	struct fuse_conn *fc = get_fuse_conn(inode);

	spin_lock(&fc->lock);
	__fuse_release_nowrite(inode);
	spin_unlock(&fc->lock);
}

M
Maxim Patlasov 已提交
1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599
static void fuse_setattr_fill(struct fuse_conn *fc, struct fuse_req *req,
			      struct inode *inode,
			      struct fuse_setattr_in *inarg_p,
			      struct fuse_attr_out *outarg_p)
{
	req->in.h.opcode = FUSE_SETATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(*inarg_p);
	req->in.args[0].value = inarg_p;
	req->out.numargs = 1;
	if (fc->minor < 9)
		req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
	else
		req->out.args[0].size = sizeof(*outarg_p);
	req->out.args[0].value = outarg_p;
}

/*
 * Flush inode->i_mtime to the server
 */
1600
int fuse_flush_times(struct inode *inode, struct fuse_file *ff)
M
Maxim Patlasov 已提交
1601 1602
{
	struct fuse_conn *fc = get_fuse_conn(inode);
M
Miklos Szeredi 已提交
1603
	struct fuse_req *req;
M
Maxim Patlasov 已提交
1604 1605 1606 1607
	struct fuse_setattr_in inarg;
	struct fuse_attr_out outarg;
	int err;

M
Miklos Szeredi 已提交
1608 1609 1610
	req = fuse_get_req_nopages(fc);
	if (IS_ERR(req))
		return PTR_ERR(req);
M
Maxim Patlasov 已提交
1611 1612 1613 1614

	memset(&inarg, 0, sizeof(inarg));
	memset(&outarg, 0, sizeof(outarg));

1615
	inarg.valid = FATTR_MTIME;
M
Maxim Patlasov 已提交
1616 1617
	inarg.mtime = inode->i_mtime.tv_sec;
	inarg.mtimensec = inode->i_mtime.tv_nsec;
1618 1619 1620 1621 1622
	if (fc->minor >= 23) {
		inarg.valid |= FATTR_CTIME;
		inarg.ctime = inode->i_ctime.tv_sec;
		inarg.ctimensec = inode->i_ctime.tv_nsec;
	}
M
Miklos Szeredi 已提交
1623 1624 1625 1626
	if (ff) {
		inarg.valid |= FATTR_FH;
		inarg.fh = ff->fh;
	}
M
Maxim Patlasov 已提交
1627 1628 1629 1630 1631 1632 1633 1634
	fuse_setattr_fill(fc, req, inode, &inarg, &outarg);
	fuse_request_send(fc, req);
	err = req->out.h.error;
	fuse_put_request(fc, req);

	return err;
}

1635 1636 1637 1638 1639
/*
 * Set attributes, and at the same time refresh them.
 *
 * Truncation is slightly complicated, because the 'truncate' request
 * may fail, in which case we don't want to touch the mapping.
M
Miklos Szeredi 已提交
1640 1641
 * vmtruncate() doesn't allow for this case, so do the rlimit checking
 * and the actual truncation by hand.
1642
 */
1643 1644
int fuse_do_setattr(struct inode *inode, struct iattr *attr,
		    struct file *file)
1645 1646
{
	struct fuse_conn *fc = get_fuse_conn(inode);
1647
	struct fuse_inode *fi = get_fuse_inode(inode);
1648 1649 1650
	struct fuse_req *req;
	struct fuse_setattr_in inarg;
	struct fuse_attr_out outarg;
M
Miklos Szeredi 已提交
1651
	bool is_truncate = false;
P
Pavel Emelyanov 已提交
1652
	bool is_wb = fc->writeback_cache;
M
Miklos Szeredi 已提交
1653
	loff_t oldsize;
1654
	int err;
M
Maxim Patlasov 已提交
1655
	bool trust_local_mtime = is_wb && S_ISREG(inode->i_mode);
1656

1657 1658 1659 1660 1661 1662
	if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
		attr->ia_valid |= ATTR_FORCE;

	err = inode_change_ok(inode, attr);
	if (err)
		return err;
M
Miklos Szeredi 已提交
1663

M
Miklos Szeredi 已提交
1664 1665 1666 1667 1668
	if (attr->ia_valid & ATTR_OPEN) {
		if (fc->atomic_o_trunc)
			return 0;
		file = NULL;
	}
1669

1670
	if (attr->ia_valid & ATTR_SIZE)
M
Miklos Szeredi 已提交
1671
		is_truncate = true;
1672

M
Maxim Patlasov 已提交
1673
	req = fuse_get_req_nopages(fc);
1674 1675
	if (IS_ERR(req))
		return PTR_ERR(req);
1676

1677
	if (is_truncate) {
M
Miklos Szeredi 已提交
1678
		fuse_set_nowrite(inode);
1679
		set_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
1680 1681
		if (trust_local_mtime && attr->ia_size != inode->i_size)
			attr->ia_valid |= ATTR_MTIME;
1682
	}
M
Miklos Szeredi 已提交
1683

1684
	memset(&inarg, 0, sizeof(inarg));
1685
	memset(&outarg, 0, sizeof(outarg));
M
Maxim Patlasov 已提交
1686
	iattr_to_fattr(attr, &inarg, trust_local_mtime);
1687 1688 1689 1690 1691
	if (file) {
		struct fuse_file *ff = file->private_data;
		inarg.valid |= FATTR_FH;
		inarg.fh = ff->fh;
	}
1692 1693 1694 1695 1696
	if (attr->ia_valid & ATTR_SIZE) {
		/* For mandatory locking in truncate */
		inarg.valid |= FATTR_LOCKOWNER;
		inarg.lock_owner = fuse_lock_owner_id(fc, current->files);
	}
M
Maxim Patlasov 已提交
1697
	fuse_setattr_fill(fc, req, inode, &inarg, &outarg);
1698
	fuse_request_send(fc, req);
1699 1700
	err = req->out.h.error;
	fuse_put_request(fc, req);
1701 1702 1703
	if (err) {
		if (err == -EINTR)
			fuse_invalidate_attr(inode);
M
Miklos Szeredi 已提交
1704
		goto error;
1705
	}
1706

1707 1708
	if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) {
		make_bad_inode(inode);
M
Miklos Szeredi 已提交
1709 1710 1711 1712 1713
		err = -EIO;
		goto error;
	}

	spin_lock(&fc->lock);
M
Maxim Patlasov 已提交
1714 1715 1716
	/* the kernel maintains i_mtime locally */
	if (trust_local_mtime && (attr->ia_valid & ATTR_MTIME)) {
		inode->i_mtime = attr->ia_mtime;
M
Miklos Szeredi 已提交
1717
		/* FIXME: clear I_DIRTY_SYNC? */
M
Maxim Patlasov 已提交
1718 1719
	}

M
Miklos Szeredi 已提交
1720 1721 1722
	fuse_change_attributes_common(inode, &outarg.attr,
				      attr_timeout(&outarg));
	oldsize = inode->i_size;
P
Pavel Emelyanov 已提交
1723 1724 1725
	/* see the comment in fuse_change_attributes() */
	if (!is_wb || is_truncate || !S_ISREG(inode->i_mode))
		i_size_write(inode, outarg.attr.size);
M
Miklos Szeredi 已提交
1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736

	if (is_truncate) {
		/* NOTE: this may release/reacquire fc->lock */
		__fuse_release_nowrite(inode);
	}
	spin_unlock(&fc->lock);

	/*
	 * Only call invalidate_inode_pages2() after removing
	 * FUSE_NOWRITE, otherwise fuse_launder_page() would deadlock.
	 */
P
Pavel Emelyanov 已提交
1737 1738
	if ((is_truncate || !is_wb) &&
	    S_ISREG(inode->i_mode) && oldsize != outarg.attr.size) {
1739
		truncate_pagecache(inode, outarg.attr.size);
M
Miklos Szeredi 已提交
1740
		invalidate_inode_pages2(inode->i_mapping);
1741 1742
	}

1743
	clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
1744
	return 0;
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Miklos Szeredi 已提交
1745 1746 1747 1748 1749

error:
	if (is_truncate)
		fuse_release_nowrite(inode);

1750
	clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
M
Miklos Szeredi 已提交
1751
	return err;
1752 1753
}

1754 1755
static int fuse_setattr(struct dentry *entry, struct iattr *attr)
{
1756 1757 1758 1759 1760
	struct inode *inode = entry->d_inode;

	if (!fuse_allow_current_process(get_fuse_conn(inode)))
		return -EACCES;

1761
	if (attr->ia_valid & ATTR_FILE)
1762
		return fuse_do_setattr(inode, attr, attr->ia_file);
1763
	else
1764
		return fuse_do_setattr(inode, attr, NULL);
1765 1766
}

1767 1768 1769 1770
static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
			struct kstat *stat)
{
	struct inode *inode = entry->d_inode;
1771 1772
	struct fuse_conn *fc = get_fuse_conn(inode);

1773
	if (!fuse_allow_current_process(fc))
1774 1775
		return -EACCES;

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Miklos Szeredi 已提交
1776
	return fuse_update_attributes(inode, stat, NULL, NULL);
1777 1778
}

1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790
static int fuse_setxattr(struct dentry *entry, const char *name,
			 const void *value, size_t size, int flags)
{
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	struct fuse_setxattr_in inarg;
	int err;

	if (fc->no_setxattr)
		return -EOPNOTSUPP;

M
Maxim Patlasov 已提交
1791
	req = fuse_get_req_nopages(fc);
1792 1793
	if (IS_ERR(req))
		return PTR_ERR(req);
1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806

	memset(&inarg, 0, sizeof(inarg));
	inarg.size = size;
	inarg.flags = flags;
	req->in.h.opcode = FUSE_SETXATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->in.numargs = 3;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->in.args[1].size = strlen(name) + 1;
	req->in.args[1].value = name;
	req->in.args[2].size = size;
	req->in.args[2].value = value;
1807
	fuse_request_send(fc, req);
1808 1809 1810 1811 1812 1813
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (err == -ENOSYS) {
		fc->no_setxattr = 1;
		err = -EOPNOTSUPP;
	}
1814 1815
	if (!err)
		fuse_invalidate_attr(inode);
1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831
	return err;
}

static ssize_t fuse_getxattr(struct dentry *entry, const char *name,
			     void *value, size_t size)
{
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	struct fuse_getxattr_in inarg;
	struct fuse_getxattr_out outarg;
	ssize_t ret;

	if (fc->no_getxattr)
		return -EOPNOTSUPP;

M
Maxim Patlasov 已提交
1832
	req = fuse_get_req_nopages(fc);
1833 1834
	if (IS_ERR(req))
		return PTR_ERR(req);
1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854

	memset(&inarg, 0, sizeof(inarg));
	inarg.size = size;
	req->in.h.opcode = FUSE_GETXATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->in.numargs = 2;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->in.args[1].size = strlen(name) + 1;
	req->in.args[1].value = name;
	/* This is really two different operations rolled into one */
	req->out.numargs = 1;
	if (size) {
		req->out.argvar = 1;
		req->out.args[0].size = size;
		req->out.args[0].value = value;
	} else {
		req->out.args[0].size = sizeof(outarg);
		req->out.args[0].value = &outarg;
	}
1855
	fuse_request_send(fc, req);
1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877
	ret = req->out.h.error;
	if (!ret)
		ret = size ? req->out.args[0].size : outarg.size;
	else {
		if (ret == -ENOSYS) {
			fc->no_getxattr = 1;
			ret = -EOPNOTSUPP;
		}
	}
	fuse_put_request(fc, req);
	return ret;
}

static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
{
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	struct fuse_getxattr_in inarg;
	struct fuse_getxattr_out outarg;
	ssize_t ret;

1878
	if (!fuse_allow_current_process(fc))
M
Miklos Szeredi 已提交
1879 1880
		return -EACCES;

1881 1882 1883
	if (fc->no_listxattr)
		return -EOPNOTSUPP;

M
Maxim Patlasov 已提交
1884
	req = fuse_get_req_nopages(fc);
1885 1886
	if (IS_ERR(req))
		return PTR_ERR(req);
1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904

	memset(&inarg, 0, sizeof(inarg));
	inarg.size = size;
	req->in.h.opcode = FUSE_LISTXATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	/* This is really two different operations rolled into one */
	req->out.numargs = 1;
	if (size) {
		req->out.argvar = 1;
		req->out.args[0].size = size;
		req->out.args[0].value = list;
	} else {
		req->out.args[0].size = sizeof(outarg);
		req->out.args[0].value = &outarg;
	}
1905
	fuse_request_send(fc, req);
1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928
	ret = req->out.h.error;
	if (!ret)
		ret = size ? req->out.args[0].size : outarg.size;
	else {
		if (ret == -ENOSYS) {
			fc->no_listxattr = 1;
			ret = -EOPNOTSUPP;
		}
	}
	fuse_put_request(fc, req);
	return ret;
}

static int fuse_removexattr(struct dentry *entry, const char *name)
{
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	int err;

	if (fc->no_removexattr)
		return -EOPNOTSUPP;

M
Maxim Patlasov 已提交
1929
	req = fuse_get_req_nopages(fc);
1930 1931
	if (IS_ERR(req))
		return PTR_ERR(req);
1932 1933 1934 1935 1936 1937

	req->in.h.opcode = FUSE_REMOVEXATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->in.numargs = 1;
	req->in.args[0].size = strlen(name) + 1;
	req->in.args[0].value = name;
1938
	fuse_request_send(fc, req);
1939 1940 1941 1942 1943 1944
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (err == -ENOSYS) {
		fc->no_removexattr = 1;
		err = -EOPNOTSUPP;
	}
1945 1946
	if (!err)
		fuse_invalidate_attr(inode);
1947 1948 1949
	return err;
}

1950
static const struct inode_operations fuse_dir_inode_operations = {
1951
	.lookup		= fuse_lookup,
1952 1953 1954 1955 1956 1957 1958 1959
	.mkdir		= fuse_mkdir,
	.symlink	= fuse_symlink,
	.unlink		= fuse_unlink,
	.rmdir		= fuse_rmdir,
	.rename		= fuse_rename,
	.link		= fuse_link,
	.setattr	= fuse_setattr,
	.create		= fuse_create,
1960
	.atomic_open	= fuse_atomic_open,
1961
	.mknod		= fuse_mknod,
1962 1963
	.permission	= fuse_permission,
	.getattr	= fuse_getattr,
1964 1965 1966 1967
	.setxattr	= fuse_setxattr,
	.getxattr	= fuse_getxattr,
	.listxattr	= fuse_listxattr,
	.removexattr	= fuse_removexattr,
1968 1969
};

1970
static const struct file_operations fuse_dir_operations = {
M
Miklos Szeredi 已提交
1971
	.llseek		= generic_file_llseek,
1972
	.read		= generic_read_dir,
A
Al Viro 已提交
1973
	.iterate	= fuse_readdir,
1974 1975
	.open		= fuse_dir_open,
	.release	= fuse_dir_release,
1976
	.fsync		= fuse_dir_fsync,
1977 1978
	.unlocked_ioctl	= fuse_dir_ioctl,
	.compat_ioctl	= fuse_dir_compat_ioctl,
1979 1980
};

1981
static const struct inode_operations fuse_common_inode_operations = {
1982
	.setattr	= fuse_setattr,
1983 1984
	.permission	= fuse_permission,
	.getattr	= fuse_getattr,
1985 1986 1987 1988
	.setxattr	= fuse_setxattr,
	.getxattr	= fuse_getxattr,
	.listxattr	= fuse_listxattr,
	.removexattr	= fuse_removexattr,
1989 1990
};

1991
static const struct inode_operations fuse_symlink_inode_operations = {
1992
	.setattr	= fuse_setattr,
1993 1994 1995 1996
	.follow_link	= fuse_follow_link,
	.put_link	= fuse_put_link,
	.readlink	= generic_readlink,
	.getattr	= fuse_getattr,
1997 1998 1999 2000
	.setxattr	= fuse_setxattr,
	.getxattr	= fuse_getxattr,
	.listxattr	= fuse_listxattr,
	.removexattr	= fuse_removexattr,
2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017
};

void fuse_init_common(struct inode *inode)
{
	inode->i_op = &fuse_common_inode_operations;
}

void fuse_init_dir(struct inode *inode)
{
	inode->i_op = &fuse_dir_inode_operations;
	inode->i_fop = &fuse_dir_operations;
}

void fuse_init_symlink(struct inode *inode)
{
	inode->i_op = &fuse_symlink_inode_operations;
}