Beispiel #1
0
/**
 *	relayfs_create_entry - create a relayfs directory or file
 *	@name: the name of the file to create
 *	@parent: parent directory
 *	@mode: mode
 *	@chan: relay channel associated with the file
 *
 *	Returns the new dentry, NULL on failure
 *
 *	Creates a file or directory with the specifed permissions.
 */
static struct dentry *relayfs_create_entry(const char *name,
					   struct dentry *parent,
					   int mode,
					   struct rchan *chan)
{
	struct dentry *d;
	struct inode *inode;
	int error = 0;

	BUG_ON(!name || !(S_ISREG(mode) || S_ISDIR(mode)));

	error = simple_pin_fs("relayfs", &relayfs_mount, &relayfs_mount_count);
	if (error) {
		printk(KERN_ERR "Couldn't mount relayfs: errcode %d\n", error);
		return NULL;
	}

	if (!parent && relayfs_mount && relayfs_mount->mnt_sb)
		parent = relayfs_mount->mnt_sb->s_root;

	if (!parent) {
		simple_release_fs(&relayfs_mount, &relayfs_mount_count);
		return NULL;
	}

	parent = dget(parent);
	down(&parent->d_inode->i_sem);
	d = lookup_one_len(name, parent, strlen(name));
	if (IS_ERR(d)) {
		d = NULL;
		goto release_mount;
	}

	if (d->d_inode) {
		d = NULL;
		goto release_mount;
	}

	inode = relayfs_get_inode(parent->d_inode->i_sb, mode, chan);
	if (!inode) {
		d = NULL;
		goto release_mount;
	}

	d_instantiate(d, inode);
	dget(d);	/* Extra count - pin the dentry in core */

	if (S_ISDIR(mode))
		parent->d_inode->i_nlink++;

	goto exit;

release_mount:
	simple_release_fs(&relayfs_mount, &relayfs_mount_count);

exit:
	up(&parent->d_inode->i_sem);
	dput(parent);
	return d;
}
Beispiel #2
0
/**
 * sysfs_chmod_file - update the modified mode value on an object attribute.
 * @kobj: object we're acting for.
 * @attr: attribute descriptor.
 * @mode: file permissions.
 *
 */
int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
{
	struct dentry *dir = kobj->dentry;
	struct dentry *victim;
	struct inode * inode;
	struct iattr newattrs;
	int res = -ENOENT;

	mutex_lock(&dir->d_inode->i_mutex);
	victim = lookup_one_len(attr->name, dir, strlen(attr->name));
	if (!IS_ERR(victim)) {
		if (victim->d_inode &&
		    (victim->d_parent->d_inode == dir->d_inode)) {
			inode = victim->d_inode;
			mutex_lock(&inode->i_mutex);
			newattrs.ia_mode = (mode & S_IALLUGO) |
						(inode->i_mode & ~S_IALLUGO);
			newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
			res = notify_change(victim, &newattrs);
			mutex_unlock(&inode->i_mutex);
		}
		dput(victim);
	}
	mutex_unlock(&dir->d_inode->i_mutex);

	return res;
}
Beispiel #3
0
static struct dentry *get_node(int num)
{
	char s[10];
	struct dentry *root = capifs_root;
	mutex_lock(&root->d_inode->i_mutex);
	return lookup_one_len(s, root, sprintf(s, "%d", num));
}
Beispiel #4
0
static int create_by_name(const char *name, mode_t mode,
			  struct dentry *parent,
			  struct dentry **dentry)
{
	int error = 0;

	*dentry = NULL;

	/* If the parent is not specified, we create it in the root.
	 * We need the root dentry to do this, which is in the super
	 * block. A pointer to that is in the struct vfsmount that we
	 * have around.
	 */
	if (!parent)
		parent = mount->mnt_sb->s_root;

	mutex_lock(&parent->d_inode->i_mutex);
	*dentry = lookup_one_len(name, parent, strlen(name));
	if (!IS_ERR(*dentry)) {
		if ((mode & S_IFMT) == S_IFDIR)
			error = mkdir(parent->d_inode, *dentry, mode);
		else
			error = create(parent->d_inode, *dentry, mode);
		if (error)
			dput(*dentry);
	} else
		error = PTR_ERR(*dentry);
	mutex_unlock(&parent->d_inode->i_mutex);

	return error;
}
Beispiel #5
0
static struct dentry *lookup_whiteout(struct dentry *dentry)
{
	char *whname;
	int bindex = -1, bstart = -1, bend = -1;
	struct dentry *parent, *hidden_parent, *wh_dentry;

	whname = alloc_whname(dentry->d_name.name, dentry->d_name.len);
	if (IS_ERR(whname))
		return (void *)whname;

	parent = dget_parent(dentry);
	unionfs_lock_dentry(parent);
	bstart = dbstart(parent);
	bend = dbend(parent);
	wh_dentry = ERR_PTR(-ENOENT);
	for (bindex = bstart; bindex <= bend; bindex++) {
		hidden_parent = unionfs_lower_dentry_idx(parent, bindex);
		if (!hidden_parent)
			continue;
		wh_dentry = lookup_one_len(whname, hidden_parent,
				   dentry->d_name.len + UNIONFS_WHLEN);
		if (IS_ERR(wh_dentry))
			continue;
		if (wh_dentry->d_inode)
			break;
		dput(wh_dentry);
		wh_dentry = ERR_PTR(-ENOENT);
	}
	unionfs_unlock_dentry(parent);
	dput(parent);
	kfree(whname);
	return wh_dentry;
}
/*
 * Lookup one path component @name relative to a <base,mnt> path pair.
 * Behaves nearly the same as lookup_one_len (i.e., return negative dentry
 * on ENOENT), but uses the @mnt passed, so it can cross bind mounts and
 * other lower mounts properly.  If @new_mnt is non-null, will fill in the
 * new mnt there.  Caller is responsible to dput/mntput/path_put returned
 * @dentry and @new_mnt.
 */
struct dentry *__lookup_one(struct dentry *base, struct vfsmount *mnt,
			    const char *name, struct vfsmount **new_mnt)
{
	struct dentry *dentry = NULL;
	struct nameidata lower_nd;
	int err;

	/* we use flags=0 to get basic lookup */
	err = vfs_path_lookup(base, mnt, name, 0, &lower_nd);

	switch (err) {
	case 0: /* no error */
		dentry = lower_nd.path.dentry;
		if (new_mnt)
			*new_mnt = lower_nd.path.mnt; /* rc already inc'ed */
		break;
	case -ENOENT:
		 /*
		  * We don't consider ENOENT an error, and we want to return
		  * a negative dentry (ala lookup_one_len).  As we know
		  * there was no inode for this name before (-ENOENT), then
		  * it's safe to call lookup_one_len (which doesn't take a
		  * vfsmount).
		  */
		dentry = lookup_one_len(name, base, strlen(name));
		if (new_mnt)
			*new_mnt = mntget(lower_nd.path.mnt);
		break;
	default: /* all other real errors */
		dentry = ERR_PTR(err);
		break;
	}

	return dentry;
}
Beispiel #7
0
static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
			    struct kstat *stat, const char *link,
			    struct dentry *hardlink)
{
	struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
	struct inode *udir = upperdir->d_inode;
	struct dentry *newdentry;
	int err;

	mutex_lock_nested(&udir->i_mutex, I_MUTEX_PARENT);
	newdentry = lookup_one_len(dentry->d_name.name, upperdir,
				   dentry->d_name.len);
	err = PTR_ERR(newdentry);
	if (IS_ERR(newdentry))
		goto out_unlock;
	err = ovl_create_real(udir, newdentry, stat, link, hardlink, false);
	if (err)
		goto out_dput;

	ovl_dentry_version_inc(dentry->d_parent);
	ovl_dentry_update(dentry, newdentry);
	ovl_copyattr(newdentry->d_inode, inode);
	d_instantiate(dentry, inode);
	newdentry = NULL;
out_dput:
	dput(newdentry);
out_unlock:
	mutex_unlock(&udir->i_mutex);
	return err;
}
Beispiel #8
0
/**
 * Prepares a directory operation by taking the mutex on the parent inode of
 * an entry and returning a dentry for the entry.
 *
 * @param child_name   path to the entry, assumed absolute from configfs
 *		       scheduler subsystem entry.
 *
 * @return	       a valid dentry to the target entry, or error. The valid
 *		       dentry must be released with put_child_dentry.
 */
static struct dentry *get_child_dentry(const char *child_name)
{
	struct dentry *d_dir;
	struct dentry *d_child;
	const char *last_child_comp;
	const char *real_child_name = child_name;
	int err;

	d_dir = dget(krg_scheduler_subsys.su_group.cg_item.ci_dentry);

	last_child_comp = strrchr(child_name, '/');
	if (last_child_comp) {
		struct nameidata nd;

		err = vfs_path_lookup(d_dir, scheduler_fs_mount,
				      child_name, LOOKUP_PARENT, &nd);

		dput(d_dir);

		if (err)
			return ERR_PTR(err);

		d_dir = dget(nd.path.dentry);
		path_put(&nd.path);
		BUG_ON(!last_child_comp[1]);
		real_child_name = last_child_comp + 1;
	}

	mutex_lock_nested(&d_dir->d_inode->i_mutex, I_MUTEX_PARENT);
	d_child = lookup_one_len(real_child_name, d_dir, strlen(real_child_name));
	if (IS_ERR(d_child))
		mutex_unlock(&d_dir->d_inode->i_mutex);
	dput(d_dir);
	return d_child;
}
Beispiel #9
0
static int lookup_and_delete_xattr(struct inode *inode, const char *name)
{
	int err = 0;
	struct dentry *dentry, *xadir;

	xadir = open_xa_dir(inode, XATTR_REPLACE);
	if (IS_ERR(xadir))
		return PTR_ERR(xadir);

	mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
	dentry = lookup_one_len(name, xadir, strlen(name));
	if (IS_ERR(dentry)) {
		err = PTR_ERR(dentry);
		goto out_dput;
	}

	if (dentry->d_inode) {
		reiserfs_write_lock(inode->i_sb);
		err = xattr_unlink(xadir->d_inode, dentry);
		reiserfs_write_unlock(inode->i_sb);
		update_ctime(inode);
	}

	dput(dentry);
out_dput:
	mutex_unlock(&xadir->d_inode->i_mutex);
	dput(xadir);
	return err;
}
Beispiel #10
0
static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
			    struct cattr *attr, struct dentry *hardlink)
{
	struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
	struct inode *udir = upperdir->d_inode;
	struct dentry *newdentry;
	int err;

	if (!hardlink && !IS_POSIXACL(udir))
		attr->mode &= ~current_umask();

	inode_lock_nested(udir, I_MUTEX_PARENT);
	newdentry = lookup_one_len(dentry->d_name.name, upperdir,
				   dentry->d_name.len);
	err = PTR_ERR(newdentry);
	if (IS_ERR(newdentry))
		goto out_unlock;
	err = ovl_create_real(udir, newdentry, attr, hardlink, false);
	if (err)
		goto out_dput;

	if (ovl_type_merge(dentry->d_parent)) {
		/* Setting opaque here is just an optimization, allow to fail */
		ovl_set_opaque(dentry, newdentry);
	}

	ovl_instantiate(dentry, inode, newdentry, !!hardlink);
	newdentry = NULL;
out_dput:
	dput(newdentry);
out_unlock:
	inode_unlock(udir);
	return err;
}
Beispiel #11
0
static struct dentry *get_node(int num)
{
	char s[12];
	struct dentry *root = devpts_root;
	down(&root->d_inode->i_sem);
	return lookup_one_len(s, root, sprintf(s, "%d", num));
}
Beispiel #12
0
static int remove_file(struct dentry *parent, char *name)
{
	struct dentry *tmp;
	int ret;

	tmp = lookup_one_len(name, parent, strlen(name));

	if (IS_ERR(tmp)) {
		ret = PTR_ERR(tmp);
		goto bail;
	}

	spin_lock(&dcache_lock);
	spin_lock(&tmp->d_lock);
	if (!(d_unhashed(tmp) && tmp->d_inode)) {
		dget_locked(tmp);
		__d_drop(tmp);
		spin_unlock(&tmp->d_lock);
		spin_unlock(&dcache_lock);
		simple_unlink(parent->d_inode, tmp);
	} else {
		spin_unlock(&tmp->d_lock);
		spin_unlock(&dcache_lock);
	}

	ret = 0;
bail:
	/*
	 * We don't expect clients to care about the return value, but
	 * it's there if they need it.
	 */
	return ret;
}
Beispiel #13
0
Datei: dir.c Projekt: krzk/linux
static int ovl_mkdir_real(struct inode *dir, struct dentry **newdentry,
			  umode_t mode)
{
	int err;
	struct dentry *d, *dentry = *newdentry;

	err = ovl_do_mkdir(dir, dentry, mode);
	if (err)
		return err;

	if (likely(!d_unhashed(dentry)))
		return 0;

	/*
	 * vfs_mkdir() may succeed and leave the dentry passed
	 * to it unhashed and negative. If that happens, try to
	 * lookup a new hashed and positive dentry.
	 */
	d = lookup_one_len(dentry->d_name.name, dentry->d_parent,
			   dentry->d_name.len);
	if (IS_ERR(d)) {
		pr_warn("overlayfs: failed lookup after mkdir (%pd2, err=%i).\n",
			dentry, err);
		return PTR_ERR(d);
	}
	dput(dentry);
	*newdentry = d;

	return 0;
}
Beispiel #14
0
Datei: dir.c Projekt: gxt/linux
static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
			    struct kstat *stat, const char *link,
			    struct dentry *hardlink)
{
	struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
	struct inode *udir = upperdir->d_inode;
	struct dentry *newdentry;
	int err;

	if (!hardlink && !IS_POSIXACL(udir))
		stat->mode &= ~current_umask();

	inode_lock_nested(udir, I_MUTEX_PARENT);
	newdentry = lookup_one_len(dentry->d_name.name, upperdir,
				   dentry->d_name.len);
	err = PTR_ERR(newdentry);
	if (IS_ERR(newdentry))
		goto out_unlock;
	err = ovl_create_real(udir, newdentry, stat, link, hardlink, false);
	if (err)
		goto out_dput;

	ovl_instantiate(dentry, inode, newdentry, !!hardlink);
	newdentry = NULL;
out_dput:
	dput(newdentry);
out_unlock:
	inode_unlock(udir);
	return err;
}
Beispiel #15
0
static int dev_rmdir(const char *name)
{
	struct nameidata nd;
	struct dentry *dentry;
	int err;

	err = kern_path_parent(name, &nd);
	if (err)
		return err;

	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
	dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);
	if (!IS_ERR(dentry)) {
		if (dentry->d_inode) {
			if (dentry->d_inode->i_private == &thread)
				err = vfs_rmdir(nd.path.dentry->d_inode,
						dentry);
			else
				err = -EPERM;
		} else {
			err = -ENOENT;
		}
		dput(dentry);
	} else {
		err = PTR_ERR(dentry);
	}

	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
	path_put(&nd.path);
	return err;
}
Beispiel #16
0
static int
fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset,
		    u64 ino, unsigned int d_type)
{
	struct reiserfs_dentry_buf *dbuf = buf;
	struct dentry *dentry;
	WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex));

	if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
		return -ENOSPC;

	if (name[0] == '.' && (namelen < 2 ||
			       (namelen == 2 && name[1] == '.')))
		return 0;

	dentry = lookup_one_len(name, dbuf->xadir, namelen);
	if (IS_ERR(dentry)) {
		return PTR_ERR(dentry);
	} else if (!dentry->d_inode) {
		/* A directory entry exists, but no file? */
		reiserfs_error(dentry->d_sb, "xattr-20003",
			       "Corrupted directory: xattr %s listed but "
			       "not found for file %s.\n",
			       dentry->d_name.name, dbuf->xadir->d_name.name);
		dput(dentry);
		return -EIO;
	}

	dbuf->dentries[dbuf->count++] = dentry;
	return 0;
}
Beispiel #17
0
static struct dentry *ovl_workdir_create(struct vfsmount *mnt,
					 struct dentry *dentry)
{
	struct inode *dir = dentry->d_inode;
	struct dentry *work;
	int err;
	bool retried = false;

	err = mnt_want_write(mnt);
	if (err)
		return ERR_PTR(err);

	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
retry:
	work = lookup_one_len(OVL_WORKDIR_NAME, dentry,
			      strlen(OVL_WORKDIR_NAME));

	if (!IS_ERR(work)) {
		struct kstat stat = {
			.mode = S_IFDIR | 0,
		};

		if (work->d_inode) {
			err = -EEXIST;
			if (retried)
				goto out_dput;

			retried = true;
			ovl_cleanup(dir, work);
			dput(work);
			goto retry;
		}

		err = ovl_create_real(dir, work, &stat, NULL, NULL, true);
		if (err)
			goto out_dput;
	}
out_unlock:
	mutex_unlock(&dir->i_mutex);
	mnt_drop_write(mnt);

	return work;

out_dput:
	dput(work);
	work = ERR_PTR(err);
	goto out_unlock;
}

static int ovl_mount_dir(const char *name, struct path *path)
{
	int err;

	err = kern_path(name, LOOKUP_FOLLOW, path);
	if (err) {
		pr_err("overlayfs: failed to resolve '%s': %i\n", name, err);
		err = -EINVAL;
	}
	return err;
}
Beispiel #18
0
static int remove_device_files(struct super_block *sb,
			       struct ipath_devdata *dd)
{
	struct dentry *dir, *root;
	char unit[10];
	int ret;

	root = dget(sb->s_root);
	mutex_lock(&root->d_inode->i_mutex);
	snprintf(unit, sizeof unit, "%02d", dd->ipath_unit);
	dir = lookup_one_len(unit, root, strlen(unit));

	if (IS_ERR(dir)) {
		ret = PTR_ERR(dir);
		printk(KERN_ERR "Lookup of %s failed\n", unit);
		goto bail;
	}

	remove_file(dir, "flash");
	remove_file(dir, "atomic_counters");
	d_delete(dir);
	ret = simple_rmdir(root->d_inode, dir);

bail:
	mutex_unlock(&root->d_inode->i_mutex);
	dput(root);
	return ret;
}
Beispiel #19
0
static struct dentry *open_xa_dir(const struct inode *inode, int flags)
{
	struct dentry *xaroot, *xadir;
	char namebuf[17];

	xaroot = open_xa_root(inode->i_sb, flags);
	if (IS_ERR(xaroot))
		return xaroot;

	snprintf(namebuf, sizeof(namebuf), "%X.%X",
		 le32_to_cpu(INODE_PKEY(inode)->k_objectid),
		 inode->i_generation);

	mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR);

	xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
	if (!IS_ERR(xadir) && !xadir->d_inode) {
		int err = -ENODATA;
		if (xattr_may_create(flags))
			err = xattr_mkdir(xaroot->d_inode, xadir, 0700);
		if (err) {
			dput(xadir);
			xadir = ERR_PTR(err);
		}
	}

	mutex_unlock(&xaroot->d_inode->i_mutex);
	dput(xaroot);
	return xadir;
}
Beispiel #20
0
static int dev_rmdir(const char *name)
{
	struct nameidata nd;
	struct dentry *dentry;
	int err;
	struct vfsmount *dev_mnt = ve_devmnt();

	err = vfs_path_lookup(dev_mnt->mnt_root, dev_mnt,
			      name, LOOKUP_PARENT, &nd);
	if (err)
		return err;

	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
	dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);
	if (!IS_ERR(dentry)) {
		if (dentry->d_inode)
			err = vfs_rmdir(nd.path.dentry->d_inode, dentry);
		else
			err = -ENOENT;
		dput(dentry);
	} else {
		err = PTR_ERR(dentry);
	}
	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);

	path_put(&nd.path);
	return err;
}
Beispiel #21
0
/**
 * sysfs_update_file - update the modified timestamp on an object attribute.
 * @kobj: object we're acting for.
 * @attr: attribute descriptor.
 */
int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
{
	struct dentry * dir = kobj->dentry;
	struct dentry * victim;
	int res = -ENOENT;

	mutex_lock(&dir->d_inode->i_mutex);
	victim = lookup_one_len(attr->name, dir, strlen(attr->name));
	if (!IS_ERR(victim)) {
		/* make sure dentry is really there */
		if (victim->d_inode && 
		    (victim->d_parent->d_inode == dir->d_inode)) {
			victim->d_inode->i_mtime = CURRENT_TIME;
			fsnotify_modify(victim);
			res = 0;
		} else
			d_drop(victim);
		
		/**
		 * Drop the reference acquired from lookup_one_len() above.
		 */
		dput(victim);
	}
	mutex_unlock(&dir->d_inode->i_mutex);

	return res;
}
Beispiel #22
0
static int ovl_whiteout(struct dentry *upperdir, struct dentry *dentry)
{
	int err;
	struct dentry *newdentry;
	const struct cred *old_cred;
	struct cred *override_cred;

	/* FIXME: recheck lower dentry to see if whiteout is really needed */

	err = -ENOMEM;
	override_cred = ovl_prepare_creds(dentry->d_sb);
	if (!override_cred)
		goto out;

	override_cred->fsuid = make_kuid(override_cred->user_ns, 0);
	if (!uid_valid(override_cred->fsuid))
		override_cred->fsuid = GLOBAL_ROOT_UID;
	override_cred->fsgid = make_kgid(override_cred->user_ns, 0);
	if (!gid_valid(override_cred->fsgid))
		override_cred->fsgid = GLOBAL_ROOT_GID;
	old_cred = override_creds(override_cred);

	newdentry = lookup_one_len(dentry->d_name.name, upperdir,
				   dentry->d_name.len);
	err = PTR_ERR(newdentry);
	if (IS_ERR(newdentry))
		goto out_put_cred;

	/* Just been removed within the same locked region */
	WARN_ON(newdentry->d_inode);

	err = vfs_symlink(upperdir->d_inode, newdentry, ovl_whiteout_symlink);
	if (err)
		goto out_dput;

	ovl_dentry_version_inc(dentry->d_parent);

	err = ovl_do_setxattr(newdentry, ovl_whiteout_xattr, "y", 1, 0);
	if (err)
		vfs_unlink(upperdir->d_inode, newdentry, NULL);

out_dput:
	dput(newdentry);
out_put_cred:
	revert_creds(old_cred);
	put_cred(override_cred);
out:
	if (err) {
		/*
		 * There's no way to recover from failure to whiteout.
		 * What should we do?  Log a big fat error and... ?
		 */
		pr_err("overlayfs: ERROR - failed to whiteout '%s'\n",
		       dentry->d_name.name);
	}

	return err;
}
Beispiel #23
0
/*
 * Get root dentry from superblock according to prefix path mount option.
 * Return dentry with refcount + 1 on success and NULL otherwise.
 */
static struct dentry *
cifs_get_root(struct smb_vol *vol, struct super_block *sb)
{
	struct dentry *dentry;
	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
	char *full_path = NULL;
	char *s, *p;
	char sep;
	int xid;

	full_path = cifs_build_path_to_root(vol, cifs_sb,
					    cifs_sb_master_tcon(cifs_sb));
	if (full_path == NULL)
		return ERR_PTR(-ENOMEM);

	cFYI(1, "Get root dentry for %s", full_path);

	xid = GetXid();
	sep = CIFS_DIR_SEP(cifs_sb);
	dentry = dget(sb->s_root);
	p = s = full_path;

	do {
		struct inode *dir = dentry->d_inode;
		struct dentry *child;

		if (!dir) {
			dput(dentry);
			dentry = ERR_PTR(-ENOENT);
			break;
		}

		if (!S_ISDIR(dir->i_mode)) {
			dput(dentry);
			dentry = ERR_PTR(-ENOTDIR);
			break;
		}

		/* skip separators */
		while (*s == sep)
			s++;
		if (!*s)
			break;
		p = s++;
		/* next separator */
		while (*s && *s != sep)
			s++;

		mutex_lock(&dir->i_mutex);
		child = lookup_one_len(p, dentry, s - p);
		mutex_unlock(&dir->i_mutex);
		dput(dentry);
		dentry = child;
	} while (!IS_ERR(dentry));
	_FreeXid(xid);
	kfree(full_path);
	return dentry;
}
Beispiel #24
0
static void __init aafs_remove(const char *name)
{
	struct dentry *dentry;

	dentry = lookup_one_len(name, aa_fs_dentry, strlen(name));
	if (!IS_ERR(dentry)) {
		securityfs_remove(dentry);
		dput(dentry);
	}
}
Beispiel #25
0
int	do_lookup2 (struct inode *inode, const char *name, int len,
		    struct dentry **result, int lock_f)
{
	struct dentry	*tmp_dent;
	struct dentry	*r_dent;
	int		ret_code;

	if ( lock_f )
		DOWN(&(inode->i_sem));


		/* Grab a dentry for the directory. */

	tmp_dent = ovlfs_inode2dentry(inode);

	if ( tmp_dent == NULL )
	{
		WARN("failed to obtain dentry for dir inode %lu",
		      inode->i_ino);

		return	-ENOENT;
	}

		/* Perform the lookup; this will call the filesystem's */
		/*  lookup entry-point, if needed.                     */

	r_dent = lookup_one_len(name, tmp_dent, len);

	if ( IS_ERR(r_dent) )
	{
		ret_code = PTR_ERR(r_dent);
	}
	else if ( r_dent == NULL )
	{
		ret_code = -ENOENT;
	}
	else if ( r_dent->d_inode == NULL )
	{
		dput(r_dent);
		ret_code = -ENOENT;
	}
	else
	{
		ret_code = 0;

		result[0] = r_dent;
	}

	dput(tmp_dent);

	if ( lock_f )
		UP(&(inode->i_sem));

	return	ret_code;
}
Beispiel #26
0
struct dentry *__create_file(const char *name, umode_t mode,
				   struct dentry *parent, void *data,
				   const struct file_operations *fops)
{
	struct dentry *dentry = NULL;
	int error;

	pr_debug("debugfs: creating file '%s'\n",name);

	error = simple_pin_fs(&debug_fs_type, &debugfs_mount,
			      &debugfs_mount_count);
	if (error)
		goto exit;

	/* If the parent is not specified, we create it in the root.
	 * We need the root dentry to do this, which is in the super 
	 * block. A pointer to that is in the struct vfsmount that we
	 * have around.
	 */
	if (!parent)
		parent = debugfs_mount->mnt_root;

	dentry = NULL;
	mutex_lock(&parent->d_inode->i_mutex);
	dentry = lookup_one_len(name, parent, strlen(name));
	if (!IS_ERR(dentry)) {
		switch (mode & S_IFMT) {
		case S_IFDIR:
			error = debugfs_mkdir(parent->d_inode, dentry, mode);
					      
			break;
		case S_IFLNK:
			error = debugfs_link(parent->d_inode, dentry, mode,
					     data);
			break;
		default:
			error = debugfs_create(parent->d_inode, dentry, mode,
					       data, fops);
			break;
		}
		dput(dentry);
	} else
		error = PTR_ERR(dentry);
	mutex_unlock(&parent->d_inode->i_mutex);

	if (error) {
		dentry = NULL;
		simple_release_fs(&debugfs_mount, &debugfs_mount_count);
	}
exit:
	return dentry;
}
Beispiel #27
0
int devtmpfs_delete_node(struct device *dev)
{
	const char *tmp = NULL;
	const char *nodename;
	const struct cred *curr_cred;
	struct nameidata nd;
	struct dentry *dentry;
	struct kstat stat;
	int deleted = 1;
	int err;

	if (!dev_mnt)
		return 0;

	nodename = device_get_devnode(dev, NULL, &tmp);
	if (!nodename)
		return -ENOMEM;

	curr_cred = override_creds(&init_cred);
	err = vfs_path_lookup(dev_mnt->mnt_root, dev_mnt,
			      nodename, LOOKUP_PARENT, &nd);
	if (err)
		goto out;

	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
	dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);
	if (!IS_ERR(dentry)) {
		if (dentry->d_inode) {
			err = vfs_getattr(nd.path.mnt, dentry, &stat);
			if (!err && dev_mynode(dev, dentry->d_inode, &stat)) {
				err = vfs_unlink(nd.path.dentry->d_inode,
						 dentry);
				if (!err || err == -ENOENT)
					deleted = 1;
			}
		} else {
			err = -ENOENT;
		}
		dput(dentry);
	} else {
		err = PTR_ERR(dentry);
	}
	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);

	path_put(&nd.path);
	if (deleted && strchr(nodename, '/'))
		delete_path(nodename);
out:
	kfree(tmp);
	revert_creds(curr_cred);
	return err;
}
Beispiel #28
0
struct dentry *vfsub_lookup_one_len(const char *name, struct dentry *parent,
				    int len)
{
	struct dentry *d;

	LKTRTrace("%.*s/%.*s\n", AuDLNPair(parent), len, name);
	IMustLock(parent->d_inode);

	d = lookup_one_len(name, parent, len);
	if (!IS_ERR(d))
		au_update_fuse_h_inode(NULL, d); /*ignore*/
	return d;
}
Beispiel #29
0
/*
 * Create a new subvolume below @parent.  This is largely modeled after
 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 * inside this filesystem so it's quite a bit simpler.
 */
static noinline int btrfs_mksubvol(struct path *parent,
				   char *name, int namelen,
				   struct btrfs_root *snap_src)
{
	struct inode *dir  = parent->dentry->d_inode;
	struct dentry *dentry;
	int error;

	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);

	dentry = lookup_one_len(name, parent->dentry, namelen);
	error = PTR_ERR(dentry);
	if (IS_ERR(dentry))
		goto out_unlock;

	error = -EEXIST;
	if (dentry->d_inode)
		goto out_dput;

	error = mnt_want_write(parent->mnt);
	if (error)
		goto out_dput;

	error = btrfs_may_create(dir, dentry);
	if (error)
		goto out_drop_write;

	down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);

	if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
		goto out_up_read;

	if (snap_src) {
		error = create_snapshot(snap_src, dentry,
					name, namelen);
	} else {
		error = create_subvol(BTRFS_I(dir)->root, dentry,
				      name, namelen);
	}
	if (!error)
		fsnotify_mkdir(dir, dentry);
out_up_read:
	up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
out_drop_write:
	mnt_drop_write(parent->mnt);
out_dput:
	dput(dentry);
out_unlock:
	mutex_unlock(&dir->i_mutex);
	return error;
}
Beispiel #30
0
static int handle_remove(const char *nodename, struct device *dev)
{
	struct nameidata nd;
	struct dentry *dentry;
	struct kstat stat;
	int deleted = 1;
	int err;

	err = kern_path_parent(nodename, &nd);
	if (err)
		return err;

	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
	dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);
	if (!IS_ERR(dentry)) {
		if (dentry->d_inode) {
			err = vfs_getattr(nd.path.mnt, dentry, &stat);
			if (!err && dev_mynode(dev, dentry->d_inode, &stat)) {
				struct iattr newattrs;
				/*
				 * before unlinking this node, reset permissions
				 * of possible references like hardlinks
				 */
				newattrs.ia_uid = 0;
				newattrs.ia_gid = 0;
				newattrs.ia_mode = stat.mode & ~0777;
				newattrs.ia_valid =
					ATTR_UID|ATTR_GID|ATTR_MODE;
				mutex_lock(&dentry->d_inode->i_mutex);
				notify_change(dentry, &newattrs);
				mutex_unlock(&dentry->d_inode->i_mutex);
				err = vfs_unlink(nd.path.dentry->d_inode,
						 dentry);
				if (!err || err == -ENOENT)
					deleted = 1;
			}
		} else {
			err = -ENOENT;
		}
		dput(dentry);
	} else {
		err = PTR_ERR(dentry);
	}
	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);

	path_put(&nd.path);
	if (deleted && strchr(nodename, '/'))
		delete_path(nodename);
	return err;
}