Linux-libre 4.2.1-gnupck-4.2.1-gnu

1 files changed, 753 insertions, 0 deletions

diff --git a/fs/aufs/dir.c b/fs/aufs/dir.c
new file mode 100644
index 000000000..7705c2997
--- /dev/null
+++ b/fs/aufs/dir.c
@@ -0,0 +1,753 @@
+/*
+ * Copyright (C) 2005-2015 Junjiro R. Okajima
+ *
+ * This program, aufs is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * directory operations
+ */
+
+#include <linux/fs_stack.h>
+#include "aufs.h"
+
+void au_add_nlink(struct inode *dir, struct inode *h_dir)
+{
+	unsigned int nlink;
+
+	AuDebugOn(!S_ISDIR(dir->i_mode) || !S_ISDIR(h_dir->i_mode));
+
+	nlink = dir->i_nlink;
+	nlink += h_dir->i_nlink - 2;
+	if (h_dir->i_nlink < 2)
+		nlink += 2;
+	smp_mb(); /* for i_nlink */
+	/* 0 can happen in revaliding */
+	set_nlink(dir, nlink);
+}
+
+void au_sub_nlink(struct inode *dir, struct inode *h_dir)
+{
+	unsigned int nlink;
+
+	AuDebugOn(!S_ISDIR(dir->i_mode) || !S_ISDIR(h_dir->i_mode));
+
+	nlink = dir->i_nlink;
+	nlink -= h_dir->i_nlink - 2;
+	if (h_dir->i_nlink < 2)
+		nlink -= 2;
+	smp_mb(); /* for i_nlink */
+	/* nlink == 0 means the branch-fs is broken */
+	set_nlink(dir, nlink);
+}
+
+loff_t au_dir_size(struct file *file, struct dentry *dentry)
+{
+	loff_t sz;
+	aufs_bindex_t bindex, bend;
+	struct file *h_file;
+	struct dentry *h_dentry;
+
+	sz = 0;
+	if (file) {
+		AuDebugOn(!d_is_dir(file->f_path.dentry));
+
+		bend = au_fbend_dir(file);
+		for (bindex = au_fbstart(file);
+		     bindex <= bend && sz < KMALLOC_MAX_SIZE;
+		     bindex++) {
+			h_file = au_hf_dir(file, bindex);
+			if (h_file && file_inode(h_file))
+				sz += vfsub_f_size_read(h_file);
+		}
+	} else {
+		AuDebugOn(!dentry);
+		AuDebugOn(!d_is_dir(dentry));
+
+		bend = au_dbtaildir(dentry);
+		for (bindex = au_dbstart(dentry);
+		     bindex <= bend && sz < KMALLOC_MAX_SIZE;
+		     bindex++) {
+			h_dentry = au_h_dptr(dentry, bindex);
+			if (h_dentry && d_is_positive(h_dentry))
+				sz += i_size_read(d_inode(h_dentry));
+		}
+	}
+	if (sz < KMALLOC_MAX_SIZE)
+		sz = roundup_pow_of_two(sz);
+	if (sz > KMALLOC_MAX_SIZE)
+		sz = KMALLOC_MAX_SIZE;
+	else if (sz < NAME_MAX) {
+		BUILD_BUG_ON(AUFS_RDBLK_DEF < NAME_MAX);
+		sz = AUFS_RDBLK_DEF;
+	}
+	return sz;
+}
+
+struct au_dir_ts_arg {
+	struct dentry *dentry;
+	aufs_bindex_t brid;
+};
+
+static void au_do_dir_ts(void *arg)
+{
+	struct au_dir_ts_arg *a = arg;
+	struct au_dtime dt;
+	struct path h_path;
+	struct inode *dir, *h_dir;
+	struct super_block *sb;
+	struct au_branch *br;
+	struct au_hinode *hdir;
+	int err;
+	aufs_bindex_t bstart, bindex;
+
+	sb = a->dentry->d_sb;
+	if (d_really_is_negative(a->dentry))
+		goto out;
+	aufs_read_lock(a->dentry, AuLock_DW | AuLock_DIR); /* noflush */
+
+	/* no dir->i_mutex lock */
+	dir = d_inode(a->dentry);
+	bstart = au_ibstart(dir);
+	bindex = au_br_index(sb, a->brid);
+	if (bindex < bstart)
+		goto out_unlock;
+
+	br = au_sbr(sb, bindex);
+	h_path.dentry = au_h_dptr(a->dentry, bindex);
+	if (!h_path.dentry)
+		goto out_unlock;
+	h_path.mnt = au_br_mnt(br);
+	au_dtime_store(&dt, a->dentry, &h_path);
+
+	br = au_sbr(sb, bstart);
+	if (!au_br_writable(br->br_perm))
+		goto out_unlock;
+	h_path.dentry = au_h_dptr(a->dentry, bstart);
+	h_path.mnt = au_br_mnt(br);
+	err = vfsub_mnt_want_write(h_path.mnt);
+	if (err)
+		goto out_unlock;
+	hdir = au_hi(dir, bstart);
+	au_hn_imtx_lock_nested(hdir, AuLsc_I_PARENT);
+	h_dir = au_h_iptr(dir, bstart);
+	if (h_dir->i_nlink
+	    && timespec_compare(&h_dir->i_mtime, &dt.dt_mtime) < 0) {
+		dt.dt_h_path = h_path;
+		au_dtime_revert(&dt);
+	}
+	au_hn_imtx_unlock(hdir);
+	vfsub_mnt_drop_write(h_path.mnt);
+	au_cpup_attr_timesizes(dir);
+
+out_unlock:
+	aufs_read_unlock(a->dentry, AuLock_DW);
+out:
+	dput(a->dentry);
+	au_nwt_done(&au_sbi(sb)->si_nowait);
+	kfree(arg);
+}
+
+void au_dir_ts(struct inode *dir, aufs_bindex_t bindex)
+{
+	int perm, wkq_err;
+	aufs_bindex_t bstart;
+	struct au_dir_ts_arg *arg;
+	struct dentry *dentry;
+	struct super_block *sb;
+
+	IMustLock(dir);
+
+	dentry = d_find_any_alias(dir);
+	AuDebugOn(!dentry);
+	sb = dentry->d_sb;
+	bstart = au_ibstart(dir);
+	if (bstart == bindex) {
+		au_cpup_attr_timesizes(dir);
+		goto out;
+	}
+
+	perm = au_sbr_perm(sb, bstart);
+	if (!au_br_writable(perm))
+		goto out;
+
+	arg = kmalloc(sizeof(*arg), GFP_NOFS);
+	if (!arg)
+		goto out;
+
+	arg->dentry = dget(dentry); /* will be dput-ted by au_do_dir_ts() */
+	arg->brid = au_sbr_id(sb, bindex);
+	wkq_err = au_wkq_nowait(au_do_dir_ts, arg, sb, /*flags*/0);
+	if (unlikely(wkq_err)) {
+		pr_err("wkq %d\n", wkq_err);
+		dput(dentry);
+		kfree(arg);
+	}
+
+out:
+	dput(dentry);
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int reopen_dir(struct file *file)
+{
+	int err;
+	unsigned int flags;
+	aufs_bindex_t bindex, btail, bstart;
+	struct dentry *dentry, *h_dentry;
+	struct file *h_file;
+
+	/* open all lower dirs */
+	dentry = file->f_path.dentry;
+	bstart = au_dbstart(dentry);
+	for (bindex = au_fbstart(file); bindex < bstart; bindex++)
+		au_set_h_fptr(file, bindex, NULL);
+	au_set_fbstart(file, bstart);
+
+	btail = au_dbtaildir(dentry);
+	for (bindex = au_fbend_dir(file); btail < bindex; bindex--)
+		au_set_h_fptr(file, bindex, NULL);
+	au_set_fbend_dir(file, btail);
+
+	flags = vfsub_file_flags(file);
+	for (bindex = bstart; bindex <= btail; bindex++) {
+		h_dentry = au_h_dptr(dentry, bindex);
+		if (!h_dentry)
+			continue;
+		h_file = au_hf_dir(file, bindex);
+		if (h_file)
+			continue;
+
+		h_file = au_h_open(dentry, bindex, flags, file, /*force_wr*/0);
+		err = PTR_ERR(h_file);
+		if (IS_ERR(h_file))
+			goto out; /* close all? */
+		au_set_h_fptr(file, bindex, h_file);
+	}
+	au_update_figen(file);
+	/* todo: necessary? */
+	/* file->f_ra = h_file->f_ra; */
+	err = 0;
+
+out:
+	return err;
+}
+
+static int do_open_dir(struct file *file, int flags, struct file *h_file)
+{
+	int err;
+	aufs_bindex_t bindex, btail;
+	struct dentry *dentry, *h_dentry;
+
+	FiMustWriteLock(file);
+	AuDebugOn(h_file);
+
+	err = 0;
+	dentry = file->f_path.dentry;
+	file->f_version = d_inode(dentry)->i_version;
+	bindex = au_dbstart(dentry);
+	au_set_fbstart(file, bindex);
+	btail = au_dbtaildir(dentry);
+	au_set_fbend_dir(file, btail);
+	for (; !err && bindex <= btail; bindex++) {
+		h_dentry = au_h_dptr(dentry, bindex);
+		if (!h_dentry)
+			continue;
+
+		h_file = au_h_open(dentry, bindex, flags, file, /*force_wr*/0);
+		if (IS_ERR(h_file)) {
+			err = PTR_ERR(h_file);
+			break;
+		}
+		au_set_h_fptr(file, bindex, h_file);
+	}
+	au_update_figen(file);
+	/* todo: necessary? */
+	/* file->f_ra = h_file->f_ra; */
+	if (!err)
+		return 0; /* success */
+
+	/* close all */
+	for (bindex = au_fbstart(file); bindex <= btail; bindex++)
+		au_set_h_fptr(file, bindex, NULL);
+	au_set_fbstart(file, -1);
+	au_set_fbend_dir(file, -1);
+
+	return err;
+}
+
+static int aufs_open_dir(struct inode *inode __maybe_unused,
+			 struct file *file)
+{
+	int err;
+	struct super_block *sb;
+	struct au_fidir *fidir;
+
+	err = -ENOMEM;
+	sb = file->f_path.dentry->d_sb;
+	si_read_lock(sb, AuLock_FLUSH);
+	fidir = au_fidir_alloc(sb);
+	if (fidir) {
+		struct au_do_open_args args = {
+			.open	= do_open_dir,
+			.fidir	= fidir
+		};
+		err = au_do_open(file, &args);
+		if (unlikely(err))
+			kfree(fidir);
+	}
+	si_read_unlock(sb);
+	return err;
+}
+
+static int aufs_release_dir(struct inode *inode __maybe_unused,
+			    struct file *file)
+{
+	struct au_vdir *vdir_cache;
+	struct au_finfo *finfo;
+	struct au_fidir *fidir;
+	aufs_bindex_t bindex, bend;
+
+	finfo = au_fi(file);
+	fidir = finfo->fi_hdir;
+	if (fidir) {
+		au_sphl_del(&finfo->fi_hlist,
+			    &au_sbi(file->f_path.dentry->d_sb)->si_files);
+		vdir_cache = fidir->fd_vdir_cache; /* lock-free */
+		if (vdir_cache)
+			au_vdir_free(vdir_cache);
+
+		bindex = finfo->fi_btop;
+		if (bindex >= 0) {
+			/*
+			 * calls fput() instead of filp_close(),
+			 * since no dnotify or lock for the lower file.
+			 */
+			bend = fidir->fd_bbot;
+			for (; bindex <= bend; bindex++)
+				au_set_h_fptr(file, bindex, NULL);
+		}
+		kfree(fidir);
+		finfo->fi_hdir = NULL;
+	}
+	au_finfo_fin(file);
+	return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int au_do_flush_dir(struct file *file, fl_owner_t id)
+{
+	int err;
+	aufs_bindex_t bindex, bend;
+	struct file *h_file;
+
+	err = 0;
+	bend = au_fbend_dir(file);
+	for (bindex = au_fbstart(file); !err && bindex <= bend; bindex++) {
+		h_file = au_hf_dir(file, bindex);
+		if (h_file)
+			err = vfsub_flush(h_file, id);
+	}
+	return err;
+}
+
+static int aufs_flush_dir(struct file *file, fl_owner_t id)
+{
+	return au_do_flush(file, id, au_do_flush_dir);
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int au_do_fsync_dir_no_file(struct dentry *dentry, int datasync)
+{
+	int err;
+	aufs_bindex_t bend, bindex;
+	struct inode *inode;
+	struct super_block *sb;
+
+	err = 0;
+	sb = dentry->d_sb;
+	inode = d_inode(dentry);
+	IMustLock(inode);
+	bend = au_dbend(dentry);
+	for (bindex = au_dbstart(dentry); !err && bindex <= bend; bindex++) {
+		struct path h_path;
+
+		if (au_test_ro(sb, bindex, inode))
+			continue;
+		h_path.dentry = au_h_dptr(dentry, bindex);
+		if (!h_path.dentry)
+			continue;
+
+		h_path.mnt = au_sbr_mnt(sb, bindex);
+		err = vfsub_fsync(NULL, &h_path, datasync);
+	}
+
+	return err;
+}
+
+static int au_do_fsync_dir(struct file *file, int datasync)
+{
+	int err;
+	aufs_bindex_t bend, bindex;
+	struct file *h_file;
+	struct super_block *sb;
+	struct inode *inode;
+
+	err = au_reval_and_lock_fdi(file, reopen_dir, /*wlock*/1);
+	if (unlikely(err))
+		goto out;
+
+	inode = file_inode(file);
+	sb = inode->i_sb;
+	bend = au_fbend_dir(file);
+	for (bindex = au_fbstart(file); !err && bindex <= bend; bindex++) {
+		h_file = au_hf_dir(file, bindex);
+		if (!h_file || au_test_ro(sb, bindex, inode))
+			continue;
+
+		err = vfsub_fsync(h_file, &h_file->f_path, datasync);
+	}
+
+out:
+	return err;
+}
+
+/*
+ * @file may be NULL
+ */
+static int aufs_fsync_dir(struct file *file, loff_t start, loff_t end,
+			  int datasync)
+{
+	int err;
+	struct dentry *dentry;
+	struct inode *inode;
+	struct super_block *sb;
+	struct mutex *mtx;
+
+	err = 0;
+	dentry = file->f_path.dentry;
+	inode = d_inode(dentry);
+	mtx = &inode->i_mutex;
+	mutex_lock(mtx);
+	sb = dentry->d_sb;
+	si_noflush_read_lock(sb);
+	if (file)
+		err = au_do_fsync_dir(file, datasync);
+	else {
+		di_write_lock_child(dentry);
+		err = au_do_fsync_dir_no_file(dentry, datasync);
+	}
+	au_cpup_attr_timesizes(inode);
+	di_write_unlock(dentry);
+	if (file)
+		fi_write_unlock(file);
+
+	si_read_unlock(sb);
+	mutex_unlock(mtx);
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int aufs_iterate(struct file *file, struct dir_context *ctx)
+{
+	int err;
+	struct dentry *dentry;
+	struct inode *inode, *h_inode;
+	struct super_block *sb;
+
+	AuDbg("%pD, ctx{%pf, %llu}\n", file, ctx->actor, ctx->pos);
+
+	dentry = file->f_path.dentry;
+	inode = d_inode(dentry);
+	IMustLock(inode);
+
+	sb = dentry->d_sb;
+	si_read_lock(sb, AuLock_FLUSH);
+	err = au_reval_and_lock_fdi(file, reopen_dir, /*wlock*/1);
+	if (unlikely(err))
+		goto out;
+	err = au_alive_dir(dentry);
+	if (!err)
+		err = au_vdir_init(file);
+	di_downgrade_lock(dentry, AuLock_IR);
+	if (unlikely(err))
+		goto out_unlock;
+
+	h_inode = au_h_iptr(inode, au_ibstart(inode));
+	if (!au_test_nfsd()) {
+		err = au_vdir_fill_de(file, ctx);
+		fsstack_copy_attr_atime(inode, h_inode);
+	} else {
+		/*
+		 * nfsd filldir may call lookup_one_len(), vfs_getattr(),
+		 * encode_fh() and others.
+		 */
+		atomic_inc(&h_inode->i_count);
+		di_read_unlock(dentry, AuLock_IR);
+		si_read_unlock(sb);
+		err = au_vdir_fill_de(file, ctx);
+		fsstack_copy_attr_atime(inode, h_inode);
+		fi_write_unlock(file);
+		iput(h_inode);
+
+		AuTraceErr(err);
+		return err;
+	}
+
+out_unlock:
+	di_read_unlock(dentry, AuLock_IR);
+	fi_write_unlock(file);
+out:
+	si_read_unlock(sb);
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+#define AuTestEmpty_WHONLY	1
+#define AuTestEmpty_CALLED	(1 << 1)
+#define AuTestEmpty_SHWH	(1 << 2)
+#define au_ftest_testempty(flags, name)	((flags) & AuTestEmpty_##name)
+#define au_fset_testempty(flags, name) \
+	do { (flags) |= AuTestEmpty_##name; } while (0)
+#define au_fclr_testempty(flags, name) \
+	do { (flags) &= ~AuTestEmpty_##name; } while (0)
+
+#ifndef CONFIG_AUFS_SHWH
+#undef AuTestEmpty_SHWH
+#define AuTestEmpty_SHWH	0
+#endif
+
+struct test_empty_arg {
+	struct dir_context ctx;
+	struct au_nhash *whlist;
+	unsigned int flags;
+	int err;
+	aufs_bindex_t bindex;
+};
+
+static int test_empty_cb(struct dir_context *ctx, const char *__name,
+			 int namelen, loff_t offset __maybe_unused, u64 ino,
+			 unsigned int d_type)
+{
+	struct test_empty_arg *arg = container_of(ctx, struct test_empty_arg,
+						  ctx);
+	char *name = (void *)__name;
+
+	arg->err = 0;
+	au_fset_testempty(arg->flags, CALLED);
+	/* smp_mb(); */
+	if (name[0] == '.'
+	    && (namelen == 1 || (name[1] == '.' && namelen == 2)))
+		goto out; /* success */
+
+	if (namelen <= AUFS_WH_PFX_LEN
+	    || memcmp(name, AUFS_WH_PFX, AUFS_WH_PFX_LEN)) {
+		if (au_ftest_testempty(arg->flags, WHONLY)
+		    && !au_nhash_test_known_wh(arg->whlist, name, namelen))
+			arg->err = -ENOTEMPTY;
+		goto out;
+	}
+
+	name += AUFS_WH_PFX_LEN;
+	namelen -= AUFS_WH_PFX_LEN;
+	if (!au_nhash_test_known_wh(arg->whlist, name, namelen))
+		arg->err = au_nhash_append_wh
+			(arg->whlist, name, namelen, ino, d_type, arg->bindex,
+			 au_ftest_testempty(arg->flags, SHWH));
+
+out:
+	/* smp_mb(); */
+	AuTraceErr(arg->err);
+	return arg->err;
+}
+
+static int do_test_empty(struct dentry *dentry, struct test_empty_arg *arg)
+{
+	int err;
+	struct file *h_file;
+
+	h_file = au_h_open(dentry, arg->bindex,
+			   O_RDONLY | O_NONBLOCK | O_DIRECTORY | O_LARGEFILE,
+			   /*file*/NULL, /*force_wr*/0);
+	err = PTR_ERR(h_file);
+	if (IS_ERR(h_file))
+		goto out;
+
+	err = 0;
+	if (!au_opt_test(au_mntflags(dentry->d_sb), UDBA_NONE)
+	    && !file_inode(h_file)->i_nlink)
+		goto out_put;
+
+	do {
+		arg->err = 0;
+		au_fclr_testempty(arg->flags, CALLED);
+		/* smp_mb(); */
+		err = vfsub_iterate_dir(h_file, &arg->ctx);
+		if (err >= 0)
+			err = arg->err;
+	} while (!err && au_ftest_testempty(arg->flags, CALLED));
+
+out_put:
+	fput(h_file);
+	au_sbr_put(dentry->d_sb, arg->bindex);
+out:
+	return err;
+}
+
+struct do_test_empty_args {
+	int *errp;
+	struct dentry *dentry;
+	struct test_empty_arg *arg;
+};
+
+static void call_do_test_empty(void *args)
+{
+	struct do_test_empty_args *a = args;
+	*a->errp = do_test_empty(a->dentry, a->arg);
+}
+
+static int sio_test_empty(struct dentry *dentry, struct test_empty_arg *arg)
+{
+	int err, wkq_err;
+	struct dentry *h_dentry;
+	struct inode *h_inode;
+
+	h_dentry = au_h_dptr(dentry, arg->bindex);
+	h_inode = d_inode(h_dentry);
+	/* todo: i_mode changes anytime? */
+	mutex_lock_nested(&h_inode->i_mutex, AuLsc_I_CHILD);
+	err = au_test_h_perm_sio(h_inode, MAY_EXEC | MAY_READ);
+	mutex_unlock(&h_inode->i_mutex);
+	if (!err)
+		err = do_test_empty(dentry, arg);
+	else {
+		struct do_test_empty_args args = {
+			.errp	= &err,
+			.dentry	= dentry,
+			.arg	= arg
+		};
+		unsigned int flags = arg->flags;
+
+		wkq_err = au_wkq_wait(call_do_test_empty, &args);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		arg->flags = flags;
+	}
+
+	return err;
+}
+
+int au_test_empty_lower(struct dentry *dentry)
+{
+	int err;
+	unsigned int rdhash;
+	aufs_bindex_t bindex, bstart, btail;
+	struct au_nhash whlist;
+	struct test_empty_arg arg = {
+		.ctx = {
+			.actor = test_empty_cb
+		}
+	};
+	int (*test_empty)(struct dentry *dentry, struct test_empty_arg *arg);
+
+	SiMustAnyLock(dentry->d_sb);
+
+	rdhash = au_sbi(dentry->d_sb)->si_rdhash;
+	if (!rdhash)
+		rdhash = au_rdhash_est(au_dir_size(/*file*/NULL, dentry));
+	err = au_nhash_alloc(&whlist, rdhash, GFP_NOFS);
+	if (unlikely(err))
+		goto out;
+
+	arg.flags = 0;
+	arg.whlist = &whlist;
+	bstart = au_dbstart(dentry);
+	if (au_opt_test(au_mntflags(dentry->d_sb), SHWH))
+		au_fset_testempty(arg.flags, SHWH);
+	test_empty = do_test_empty;
+	if (au_opt_test(au_mntflags(dentry->d_sb), DIRPERM1))
+		test_empty = sio_test_empty;
+	arg.bindex = bstart;
+	err = test_empty(dentry, &arg);
+	if (unlikely(err))
+		goto out_whlist;
+
+	au_fset_testempty(arg.flags, WHONLY);
+	btail = au_dbtaildir(dentry);
+	for (bindex = bstart + 1; !err && bindex <= btail; bindex++) {
+		struct dentry *h_dentry;
+
+		h_dentry = au_h_dptr(dentry, bindex);
+		if (h_dentry && d_is_positive(h_dentry)) {
+			arg.bindex = bindex;
+			err = test_empty(dentry, &arg);
+		}
+	}
+
+out_whlist:
+	au_nhash_wh_free(&whlist);
+out:
+	return err;
+}
+
+int au_test_empty(struct dentry *dentry, struct au_nhash *whlist)
+{
+	int err;
+	struct test_empty_arg arg = {
+		.ctx = {
+			.actor = test_empty_cb
+		}
+	};
+	aufs_bindex_t bindex, btail;
+
+	err = 0;
+	arg.whlist = whlist;
+	arg.flags = AuTestEmpty_WHONLY;
+	if (au_opt_test(au_mntflags(dentry->d_sb), SHWH))
+		au_fset_testempty(arg.flags, SHWH);
+	btail = au_dbtaildir(dentry);
+	for (bindex = au_dbstart(dentry); !err && bindex <= btail; bindex++) {
+		struct dentry *h_dentry;
+
+		h_dentry = au_h_dptr(dentry, bindex);
+		if (h_dentry && d_is_positive(h_dentry)) {
+			arg.bindex = bindex;
+			err = sio_test_empty(dentry, &arg);
+		}
+	}
+
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+const struct file_operations aufs_dir_fop = {
+	.owner		= THIS_MODULE,
+	.llseek		= default_llseek,
+	.read		= generic_read_dir,
+	.iterate	= aufs_iterate,
+	.unlocked_ioctl	= aufs_ioctl_dir,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= aufs_compat_ioctl_dir,
+#endif
+	.open		= aufs_open_dir,
+	.release	= aufs_release_dir,
+	.flush		= aufs_flush_dir,
+	.fsync		= aufs_fsync_dir
+};