Linux-libre 4.5-gnu

1 files changed, 0 insertions, 1123 deletions

diff --git a/fs/aufs/dentry.c b/fs/aufs/dentry.c
deleted file mode 100644
index e47a7e6c4..000000000
--- a/fs/aufs/dentry.c
+++ /dev/null
@@ -1,1123 +0,0 @@
-/*
- * Copyright (C) 2005-2016 Junjiro R. Okajima
- */
-
-/*
- * lookup and dentry operations
- */
-
-#include <linux/namei.h>
-#include "aufs.h"
-
-#define AuLkup_ALLOW_NEG	1
-#define AuLkup_IGNORE_PERM	(1 << 1)
-#define au_ftest_lkup(flags, name)	((flags) & AuLkup_##name)
-#define au_fset_lkup(flags, name) \
-	do { (flags) |= AuLkup_##name; } while (0)
-#define au_fclr_lkup(flags, name) \
-	do { (flags) &= ~AuLkup_##name; } while (0)
-
-struct au_do_lookup_args {
-	unsigned int		flags;
-	mode_t			type;
-};
-
-/*
- * returns positive/negative dentry, NULL or an error.
- * NULL means whiteout-ed or not-found.
- */
-static struct dentry*
-au_do_lookup(struct dentry *h_parent, struct dentry *dentry,
-	     aufs_bindex_t bindex, struct qstr *wh_name,
-	     struct au_do_lookup_args *args)
-{
-	struct dentry *h_dentry;
-	struct inode *h_inode;
-	struct au_branch *br;
-	int wh_found, opq;
-	unsigned char wh_able;
-	const unsigned char allow_neg = !!au_ftest_lkup(args->flags, ALLOW_NEG);
-	const unsigned char ignore_perm = !!au_ftest_lkup(args->flags,
-							  IGNORE_PERM);
-
-	wh_found = 0;
-	br = au_sbr(dentry->d_sb, bindex);
-	wh_able = !!au_br_whable(br->br_perm);
-	if (wh_able)
-		wh_found = au_wh_test(h_parent, wh_name, /*try_sio*/0);
-	h_dentry = ERR_PTR(wh_found);
-	if (!wh_found)
-		goto real_lookup;
-	if (unlikely(wh_found < 0))
-		goto out;
-
-	/* We found a whiteout */
-	/* au_set_dbend(dentry, bindex); */
-	au_set_dbwh(dentry, bindex);
-	if (!allow_neg)
-		return NULL; /* success */
-
-real_lookup:
-	if (!ignore_perm)
-		h_dentry = vfsub_lkup_one(&dentry->d_name, h_parent);
-	else
-		h_dentry = au_sio_lkup_one(&dentry->d_name, h_parent);
-	if (IS_ERR(h_dentry)) {
-		if (PTR_ERR(h_dentry) == -ENAMETOOLONG
-		    && !allow_neg)
-			h_dentry = NULL;
-		goto out;
-	}
-
-	h_inode = d_inode(h_dentry);
-	if (d_is_negative(h_dentry)) {
-		if (!allow_neg)
-			goto out_neg;
-	} else if (wh_found
-		   || (args->type && args->type != (h_inode->i_mode & S_IFMT)))
-		goto out_neg;
-
-	if (au_dbend(dentry) <= bindex)
-		au_set_dbend(dentry, bindex);
-	if (au_dbstart(dentry) < 0 || bindex < au_dbstart(dentry))
-		au_set_dbstart(dentry, bindex);
-	au_set_h_dptr(dentry, bindex, h_dentry);
-
-	if (!d_is_dir(h_dentry)
-	    || !wh_able
-	    || (d_really_is_positive(dentry) && !d_is_dir(dentry)))
-		goto out; /* success */
-
-	mutex_lock_nested(&h_inode->i_mutex, AuLsc_I_CHILD);
-	opq = au_diropq_test(h_dentry);
-	mutex_unlock(&h_inode->i_mutex);
-	if (opq > 0)
-		au_set_dbdiropq(dentry, bindex);
-	else if (unlikely(opq < 0)) {
-		au_set_h_dptr(dentry, bindex, NULL);
-		h_dentry = ERR_PTR(opq);
-	}
-	goto out;
-
-out_neg:
-	dput(h_dentry);
-	h_dentry = NULL;
-out:
-	return h_dentry;
-}
-
-static int au_test_shwh(struct super_block *sb, const struct qstr *name)
-{
-	if (unlikely(!au_opt_test(au_mntflags(sb), SHWH)
-		     && !strncmp(name->name, AUFS_WH_PFX, AUFS_WH_PFX_LEN)))
-		return -EPERM;
-	return 0;
-}
-
-/*
- * returns the number of lower positive dentries,
- * otherwise an error.
- * can be called at unlinking with @type is zero.
- */
-int au_lkup_dentry(struct dentry *dentry, aufs_bindex_t bstart, mode_t type)
-{
-	int npositive, err;
-	aufs_bindex_t bindex, btail, bdiropq;
-	unsigned char isdir, dirperm1;
-	struct qstr whname;
-	struct au_do_lookup_args args = {
-		.flags		= 0,
-		.type		= type
-	};
-	const struct qstr *name = &dentry->d_name;
-	struct dentry *parent;
-	struct super_block *sb;
-
-	sb = dentry->d_sb;
-	err = au_test_shwh(sb, name);
-	if (unlikely(err))
-		goto out;
-
-	err = au_wh_name_alloc(&whname, name);
-	if (unlikely(err))
-		goto out;
-
-	isdir = !!d_is_dir(dentry);
-	if (!type)
-		au_fset_lkup(args.flags, ALLOW_NEG);
-	dirperm1 = !!au_opt_test(au_mntflags(sb), DIRPERM1);
-
-	npositive = 0;
-	parent = dget_parent(dentry);
-	btail = au_dbtaildir(parent);
-	for (bindex = bstart; bindex <= btail; bindex++) {
-		struct dentry *h_parent, *h_dentry;
-		struct inode *h_inode, *h_dir;
-
-		h_dentry = au_h_dptr(dentry, bindex);
-		if (h_dentry) {
-			if (d_is_positive(h_dentry))
-				npositive++;
-			if (type != S_IFDIR)
-				break;
-			continue;
-		}
-		h_parent = au_h_dptr(parent, bindex);
-		if (!h_parent || !d_is_dir(h_parent))
-			continue;
-
-		h_dir = d_inode(h_parent);
-		mutex_lock_nested(&h_dir->i_mutex, AuLsc_I_PARENT);
-		h_dentry = au_do_lookup(h_parent, dentry, bindex, &whname,
-					&args);
-		mutex_unlock(&h_dir->i_mutex);
-		err = PTR_ERR(h_dentry);
-		if (IS_ERR(h_dentry))
-			goto out_parent;
-		if (h_dentry)
-			au_fclr_lkup(args.flags, ALLOW_NEG);
-		if (dirperm1)
-			au_fset_lkup(args.flags, IGNORE_PERM);
-
-		if (au_dbwh(dentry) == bindex)
-			break;
-		if (!h_dentry)
-			continue;
-		if (d_is_negative(h_dentry))
-			continue;
-		h_inode = d_inode(h_dentry);
-		npositive++;
-		if (!args.type)
-			args.type = h_inode->i_mode & S_IFMT;
-		if (args.type != S_IFDIR)
-			break;
-		else if (isdir) {
-			/* the type of lower may be different */
-			bdiropq = au_dbdiropq(dentry);
-			if (bdiropq >= 0 && bdiropq <= bindex)
-				break;
-		}
-	}
-
-	if (npositive) {
-		AuLabel(positive);
-		au_update_dbstart(dentry);
-	}
-	err = npositive;
-	if (unlikely(!au_opt_test(au_mntflags(sb), UDBA_NONE)
-		     && au_dbstart(dentry) < 0)) {
-		err = -EIO;
-		AuIOErr("both of real entry and whiteout found, %pd, err %d\n",
-			dentry, err);
-	}
-
-out_parent:
-	dput(parent);
-	kfree(whname.name);
-out:
-	return err;
-}
-
-struct dentry *au_sio_lkup_one(struct qstr *name, struct dentry *parent)
-{
-	struct dentry *dentry;
-	int wkq_err;
-
-	if (!au_test_h_perm_sio(d_inode(parent), MAY_EXEC))
-		dentry = vfsub_lkup_one(name, parent);
-	else {
-		struct vfsub_lkup_one_args args = {
-			.errp	= &dentry,
-			.name	= name,
-			.parent	= parent
-		};
-
-		wkq_err = au_wkq_wait(vfsub_call_lkup_one, &args);
-		if (unlikely(wkq_err))
-			dentry = ERR_PTR(wkq_err);
-	}
-
-	return dentry;
-}
-
-/*
- * lookup @dentry on @bindex which should be negative.
- */
-int au_lkup_neg(struct dentry *dentry, aufs_bindex_t bindex, int wh)
-{
-	int err;
-	struct dentry *parent, *h_parent, *h_dentry;
-	struct au_branch *br;
-
-	parent = dget_parent(dentry);
-	h_parent = au_h_dptr(parent, bindex);
-	br = au_sbr(dentry->d_sb, bindex);
-	if (wh)
-		h_dentry = au_whtmp_lkup(h_parent, br, &dentry->d_name);
-	else
-		h_dentry = au_sio_lkup_one(&dentry->d_name, h_parent);
-	err = PTR_ERR(h_dentry);
-	if (IS_ERR(h_dentry))
-		goto out;
-	if (unlikely(d_is_positive(h_dentry))) {
-		err = -EIO;
-		AuIOErr("%pd should be negative on b%d.\n", h_dentry, bindex);
-		dput(h_dentry);
-		goto out;
-	}
-
-	err = 0;
-	if (bindex < au_dbstart(dentry))
-		au_set_dbstart(dentry, bindex);
-	if (au_dbend(dentry) < bindex)
-		au_set_dbend(dentry, bindex);
-	au_set_h_dptr(dentry, bindex, h_dentry);
-
-out:
-	dput(parent);
-	return err;
-}
-
-/* ---------------------------------------------------------------------- */
-
-/* subset of struct inode */
-struct au_iattr {
-	unsigned long		i_ino;
-	/* unsigned int		i_nlink; */
-	kuid_t			i_uid;
-	kgid_t			i_gid;
-	u64			i_version;
-/*
-	loff_t			i_size;
-	blkcnt_t		i_blocks;
-*/
-	umode_t			i_mode;
-};
-
-static void au_iattr_save(struct au_iattr *ia, struct inode *h_inode)
-{
-	ia->i_ino = h_inode->i_ino;
-	/* ia->i_nlink = h_inode->i_nlink; */
-	ia->i_uid = h_inode->i_uid;
-	ia->i_gid = h_inode->i_gid;
-	ia->i_version = h_inode->i_version;
-/*
-	ia->i_size = h_inode->i_size;
-	ia->i_blocks = h_inode->i_blocks;
-*/
-	ia->i_mode = (h_inode->i_mode & S_IFMT);
-}
-
-static int au_iattr_test(struct au_iattr *ia, struct inode *h_inode)
-{
-	return ia->i_ino != h_inode->i_ino
-		/* || ia->i_nlink != h_inode->i_nlink */
-		|| !uid_eq(ia->i_uid, h_inode->i_uid)
-		|| !gid_eq(ia->i_gid, h_inode->i_gid)
-		|| ia->i_version != h_inode->i_version
-/*
-		|| ia->i_size != h_inode->i_size
-		|| ia->i_blocks != h_inode->i_blocks
-*/
-		|| ia->i_mode != (h_inode->i_mode & S_IFMT);
-}
-
-static int au_h_verify_dentry(struct dentry *h_dentry, struct dentry *h_parent,
-			      struct au_branch *br)
-{
-	int err;
-	struct au_iattr ia;
-	struct inode *h_inode;
-	struct dentry *h_d;
-	struct super_block *h_sb;
-
-	err = 0;
-	memset(&ia, -1, sizeof(ia));
-	h_sb = h_dentry->d_sb;
-	h_inode = NULL;
-	if (d_is_positive(h_dentry)) {
-		h_inode = d_inode(h_dentry);
-		au_iattr_save(&ia, h_inode);
-	} else if (au_test_nfs(h_sb) || au_test_fuse(h_sb))
-		/* nfs d_revalidate may return 0 for negative dentry */
-		/* fuse d_revalidate always return 0 for negative dentry */
-		goto out;
-
-	/* main purpose is namei.c:cached_lookup() and d_revalidate */
-	h_d = vfsub_lkup_one(&h_dentry->d_name, h_parent);
-	err = PTR_ERR(h_d);
-	if (IS_ERR(h_d))
-		goto out;
-
-	err = 0;
-	if (unlikely(h_d != h_dentry
-		     || d_inode(h_d) != h_inode
-		     || (h_inode && au_iattr_test(&ia, h_inode))))
-		err = au_busy_or_stale();
-	dput(h_d);
-
-out:
-	AuTraceErr(err);
-	return err;
-}
-
-int au_h_verify(struct dentry *h_dentry, unsigned int udba, struct inode *h_dir,
-		struct dentry *h_parent, struct au_branch *br)
-{
-	int err;
-
-	err = 0;
-	if (udba == AuOpt_UDBA_REVAL
-	    && !au_test_fs_remote(h_dentry->d_sb)) {
-		IMustLock(h_dir);
-		err = (d_inode(h_dentry->d_parent) != h_dir);
-	} else if (udba != AuOpt_UDBA_NONE)
-		err = au_h_verify_dentry(h_dentry, h_parent, br);
-
-	return err;
-}
-
-/* ---------------------------------------------------------------------- */
-
-static int au_do_refresh_hdentry(struct dentry *dentry, struct dentry *parent)
-{
-	int err;
-	aufs_bindex_t new_bindex, bindex, bend, bwh, bdiropq;
-	struct au_hdentry tmp, *p, *q;
-	struct au_dinfo *dinfo;
-	struct super_block *sb;
-
-	DiMustWriteLock(dentry);
-
-	sb = dentry->d_sb;
-	dinfo = au_di(dentry);
-	bend = dinfo->di_bend;
-	bwh = dinfo->di_bwh;
-	bdiropq = dinfo->di_bdiropq;
-	p = dinfo->di_hdentry + dinfo->di_bstart;
-	for (bindex = dinfo->di_bstart; bindex <= bend; bindex++, p++) {
-		if (!p->hd_dentry)
-			continue;
-
-		new_bindex = au_br_index(sb, p->hd_id);
-		if (new_bindex == bindex)
-			continue;
-
-		if (dinfo->di_bwh == bindex)
-			bwh = new_bindex;
-		if (dinfo->di_bdiropq == bindex)
-			bdiropq = new_bindex;
-		if (new_bindex < 0) {
-			au_hdput(p);
-			p->hd_dentry = NULL;
-			continue;
-		}
-
-		/* swap two lower dentries, and loop again */
-		q = dinfo->di_hdentry + new_bindex;
-		tmp = *q;
-		*q = *p;
-		*p = tmp;
-		if (tmp.hd_dentry) {
-			bindex--;
-			p--;
-		}
-	}
-
-	dinfo->di_bwh = -1;
-	if (bwh >= 0 && bwh <= au_sbend(sb) && au_sbr_whable(sb, bwh))
-		dinfo->di_bwh = bwh;
-
-	dinfo->di_bdiropq = -1;
-	if (bdiropq >= 0
-	    && bdiropq <= au_sbend(sb)
-	    && au_sbr_whable(sb, bdiropq))
-		dinfo->di_bdiropq = bdiropq;
-
-	err = -EIO;
-	dinfo->di_bstart = -1;
-	dinfo->di_bend = -1;
-	bend = au_dbend(parent);
-	p = dinfo->di_hdentry;
-	for (bindex = 0; bindex <= bend; bindex++, p++)
-		if (p->hd_dentry) {
-			dinfo->di_bstart = bindex;
-			break;
-		}
-
-	if (dinfo->di_bstart >= 0) {
-		p = dinfo->di_hdentry + bend;
-		for (bindex = bend; bindex >= 0; bindex--, p--)
-			if (p->hd_dentry) {
-				dinfo->di_bend = bindex;
-				err = 0;
-				break;
-			}
-	}
-
-	return err;
-}
-
-static void au_do_hide(struct dentry *dentry)
-{
-	struct inode *inode;
-
-	if (d_really_is_positive(dentry)) {
-		inode = d_inode(dentry);
-		if (!d_is_dir(dentry)) {
-			if (inode->i_nlink && !d_unhashed(dentry))
-				drop_nlink(inode);
-		} else {
-			clear_nlink(inode);
-			/* stop next lookup */
-			inode->i_flags |= S_DEAD;
-		}
-		smp_mb(); /* necessary? */
-	}
-	d_drop(dentry);
-}
-
-static int au_hide_children(struct dentry *parent)
-{
-	int err, i, j, ndentry;
-	struct au_dcsub_pages dpages;
-	struct au_dpage *dpage;
-	struct dentry *dentry;
-
-	err = au_dpages_init(&dpages, GFP_NOFS);
-	if (unlikely(err))
-		goto out;
-	err = au_dcsub_pages(&dpages, parent, NULL, NULL);
-	if (unlikely(err))
-		goto out_dpages;
-
-	/* in reverse order */
-	for (i = dpages.ndpage - 1; i >= 0; i--) {
-		dpage = dpages.dpages + i;
-		ndentry = dpage->ndentry;
-		for (j = ndentry - 1; j >= 0; j--) {
-			dentry = dpage->dentries[j];
-			if (dentry != parent)
-				au_do_hide(dentry);
-		}
-	}
-
-out_dpages:
-	au_dpages_free(&dpages);
-out:
-	return err;
-}
-
-static void au_hide(struct dentry *dentry)
-{
-	int err;
-
-	AuDbgDentry(dentry);
-	if (d_is_dir(dentry)) {
-		/* shrink_dcache_parent(dentry); */
-		err = au_hide_children(dentry);
-		if (unlikely(err))
-			AuIOErr("%pd, failed hiding children, ignored %d\n",
-				dentry, err);
-	}
-	au_do_hide(dentry);
-}
-
-/*
- * By adding a dirty branch, a cached dentry may be affected in various ways.
- *
- * a dirty branch is added
- * - on the top of layers
- * - in the middle of layers
- * - to the bottom of layers
- *
- * on the added branch there exists
- * - a whiteout
- * - a diropq
- * - a same named entry
- *   + exist
- *     * negative --> positive
- *     * positive --> positive
- *	 - type is unchanged
- *	 - type is changed
- *   + doesn't exist
- *     * negative --> negative
- *     * positive --> negative (rejected by au_br_del() for non-dir case)
- * - none
- */
-static int au_refresh_by_dinfo(struct dentry *dentry, struct au_dinfo *dinfo,
-			       struct au_dinfo *tmp)
-{
-	int err;
-	aufs_bindex_t bindex, bend;
-	struct {
-		struct dentry *dentry;
-		struct inode *inode;
-		mode_t mode;
-	} orig_h, tmp_h = {
-		.dentry = NULL
-	};
-	struct au_hdentry *hd;
-	struct inode *inode, *h_inode;
-	struct dentry *h_dentry;
-
-	err = 0;
-	AuDebugOn(dinfo->di_bstart < 0);
-	orig_h.mode = 0;
-	orig_h.dentry = dinfo->di_hdentry[dinfo->di_bstart].hd_dentry;
-	orig_h.inode = NULL;
-	if (d_is_positive(orig_h.dentry)) {
-		orig_h.inode = d_inode(orig_h.dentry);
-		orig_h.mode = orig_h.inode->i_mode & S_IFMT;
-	}
-	if (tmp->di_bstart >= 0) {
-		tmp_h.dentry = tmp->di_hdentry[tmp->di_bstart].hd_dentry;
-		if (d_is_positive(tmp_h.dentry)) {
-			tmp_h.inode = d_inode(tmp_h.dentry);
-			tmp_h.mode = tmp_h.inode->i_mode & S_IFMT;
-		}
-	}
-
-	inode = NULL;
-	if (d_really_is_positive(dentry))
-		inode = d_inode(dentry);
-	if (!orig_h.inode) {
-		AuDbg("nagative originally\n");
-		if (inode) {
-			au_hide(dentry);
-			goto out;
-		}
-		AuDebugOn(inode);
-		AuDebugOn(dinfo->di_bstart != dinfo->di_bend);
-		AuDebugOn(dinfo->di_bdiropq != -1);
-
-		if (!tmp_h.inode) {
-			AuDbg("negative --> negative\n");
-			/* should have only one negative lower */
-			if (tmp->di_bstart >= 0
-			    && tmp->di_bstart < dinfo->di_bstart) {
-				AuDebugOn(tmp->di_bstart != tmp->di_bend);
-				AuDebugOn(dinfo->di_bstart != dinfo->di_bend);
-				au_set_h_dptr(dentry, dinfo->di_bstart, NULL);
-				au_di_cp(dinfo, tmp);
-				hd = tmp->di_hdentry + tmp->di_bstart;
-				au_set_h_dptr(dentry, tmp->di_bstart,
-					      dget(hd->hd_dentry));
-			}
-			au_dbg_verify_dinode(dentry);
-		} else {
-			AuDbg("negative --> positive\n");
-			/*
-			 * similar to the behaviour of creating with bypassing
-			 * aufs.
-			 * unhash it in order to force an error in the
-			 * succeeding create operation.
-			 * we should not set S_DEAD here.
-			 */
-			d_drop(dentry);
-			/* au_di_swap(tmp, dinfo); */
-			au_dbg_verify_dinode(dentry);
-		}
-	} else {
-		AuDbg("positive originally\n");
-		/* inode may be NULL */
-		AuDebugOn(inode && (inode->i_mode & S_IFMT) != orig_h.mode);
-		if (!tmp_h.inode) {
-			AuDbg("positive --> negative\n");
-			/* or bypassing aufs */
-			au_hide(dentry);
-			if (tmp->di_bwh >= 0 && tmp->di_bwh <= dinfo->di_bstart)
-				dinfo->di_bwh = tmp->di_bwh;
-			if (inode)
-				err = au_refresh_hinode_self(inode);
-			au_dbg_verify_dinode(dentry);
-		} else if (orig_h.mode == tmp_h.mode) {
-			AuDbg("positive --> positive, same type\n");
-			if (!S_ISDIR(orig_h.mode)
-			    && dinfo->di_bstart > tmp->di_bstart) {
-				/*
-				 * similar to the behaviour of removing and
-				 * creating.
-				 */
-				au_hide(dentry);
-				if (inode)
-					err = au_refresh_hinode_self(inode);
-				au_dbg_verify_dinode(dentry);
-			} else {
-				/* fill empty slots */
-				if (dinfo->di_bstart > tmp->di_bstart)
-					dinfo->di_bstart = tmp->di_bstart;
-				if (dinfo->di_bend < tmp->di_bend)
-					dinfo->di_bend = tmp->di_bend;
-				dinfo->di_bwh = tmp->di_bwh;
-				dinfo->di_bdiropq = tmp->di_bdiropq;
-				hd = tmp->di_hdentry;
-				bend = dinfo->di_bend;
-				for (bindex = tmp->di_bstart; bindex <= bend;
-				     bindex++) {
-					if (au_h_dptr(dentry, bindex))
-						continue;
-					h_dentry = hd[bindex].hd_dentry;
-					if (!h_dentry)
-						continue;
-					AuDebugOn(d_is_negative(h_dentry));
-					h_inode = d_inode(h_dentry);
-					AuDebugOn(orig_h.mode
-						  != (h_inode->i_mode
-						      & S_IFMT));
-					au_set_h_dptr(dentry, bindex,
-						      dget(h_dentry));
-				}
-				err = au_refresh_hinode(inode, dentry);
-				au_dbg_verify_dinode(dentry);
-			}
-		} else {
-			AuDbg("positive --> positive, different type\n");
-			/* similar to the behaviour of removing and creating */
-			au_hide(dentry);
-			if (inode)
-				err = au_refresh_hinode_self(inode);
-			au_dbg_verify_dinode(dentry);
-		}
-	}
-
-out:
-	return err;
-}
-
-void au_refresh_dop(struct dentry *dentry, int force_reval)
-{
-	const struct dentry_operations *dop
-		= force_reval ? &aufs_dop : dentry->d_sb->s_d_op;
-	static const unsigned int mask
-		= DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE;
-
-	BUILD_BUG_ON(sizeof(mask) != sizeof(dentry->d_flags));
-
-	if (dentry->d_op == dop)
-		return;
-
-	AuDbg("%pd\n", dentry);
-	spin_lock(&dentry->d_lock);
-	if (dop == &aufs_dop)
-		dentry->d_flags |= mask;
-	else
-		dentry->d_flags &= ~mask;
-	dentry->d_op = dop;
-	spin_unlock(&dentry->d_lock);
-}
-
-int au_refresh_dentry(struct dentry *dentry, struct dentry *parent)
-{
-	int err, ebrange;
-	unsigned int sigen;
-	struct au_dinfo *dinfo, *tmp;
-	struct super_block *sb;
-	struct inode *inode;
-
-	DiMustWriteLock(dentry);
-	AuDebugOn(IS_ROOT(dentry));
-	AuDebugOn(d_really_is_negative(parent));
-
-	sb = dentry->d_sb;
-	sigen = au_sigen(sb);
-	err = au_digen_test(parent, sigen);
-	if (unlikely(err))
-		goto out;
-
-	dinfo = au_di(dentry);
-	err = au_di_realloc(dinfo, au_sbend(sb) + 1);
-	if (unlikely(err))
-		goto out;
-	ebrange = au_dbrange_test(dentry);
-	if (!ebrange)
-		ebrange = au_do_refresh_hdentry(dentry, parent);
-
-	if (d_unhashed(dentry) || ebrange /* || dinfo->di_tmpfile */) {
-		AuDebugOn(au_dbstart(dentry) < 0 && au_dbend(dentry) >= 0);
-		if (d_really_is_positive(dentry)) {
-			inode = d_inode(dentry);
-			err = au_refresh_hinode_self(inode);
-		}
-		au_dbg_verify_dinode(dentry);
-		if (!err)
-			goto out_dgen; /* success */
-		goto out;
-	}
-
-	/* temporary dinfo */
-	AuDbgDentry(dentry);
-	err = -ENOMEM;
-	tmp = au_di_alloc(sb, AuLsc_DI_TMP);
-	if (unlikely(!tmp))
-		goto out;
-	au_di_swap(tmp, dinfo);
-	/* returns the number of positive dentries */
-	/*
-	 * if current working dir is removed, it returns an error.
-	 * but the dentry is legal.
-	 */
-	err = au_lkup_dentry(dentry, /*bstart*/0, /*type*/0);
-	AuDbgDentry(dentry);
-	au_di_swap(tmp, dinfo);
-	if (err == -ENOENT)
-		err = 0;
-	if (err >= 0) {
-		/* compare/refresh by dinfo */
-		AuDbgDentry(dentry);
-		err = au_refresh_by_dinfo(dentry, dinfo, tmp);
-		au_dbg_verify_dinode(dentry);
-		AuTraceErr(err);
-	}
-	au_rw_write_unlock(&tmp->di_rwsem);
-	au_di_free(tmp);
-	if (unlikely(err))
-		goto out;
-
-out_dgen:
-	au_update_digen(dentry);
-out:
-	if (unlikely(err && !(dentry->d_flags & DCACHE_NFSFS_RENAMED))) {
-		AuIOErr("failed refreshing %pd, %d\n", dentry, err);
-		AuDbgDentry(dentry);
-	}
-	AuTraceErr(err);
-	return err;
-}
-
-static int au_do_h_d_reval(struct dentry *h_dentry, unsigned int flags,
-			   struct dentry *dentry, aufs_bindex_t bindex)
-{
-	int err, valid;
-
-	err = 0;
-	if (!(h_dentry->d_flags & DCACHE_OP_REVALIDATE))
-		goto out;
-
-	AuDbg("b%d\n", bindex);
-	/*
-	 * gave up supporting LOOKUP_CREATE/OPEN for lower fs,
-	 * due to whiteout and branch permission.
-	 */
-	flags &= ~(/*LOOKUP_PARENT |*/ LOOKUP_OPEN | LOOKUP_CREATE
-		   | LOOKUP_FOLLOW | LOOKUP_EXCL);
-	/* it may return tri-state */
-	valid = h_dentry->d_op->d_revalidate(h_dentry, flags);
-
-	if (unlikely(valid < 0))
-		err = valid;
-	else if (!valid)
-		err = -EINVAL;
-
-out:
-	AuTraceErr(err);
-	return err;
-}
-
-/* todo: remove this */
-static int h_d_revalidate(struct dentry *dentry, struct inode *inode,
-			  unsigned int flags, int do_udba)
-{
-	int err;
-	umode_t mode, h_mode;
-	aufs_bindex_t bindex, btail, bstart, ibs, ibe;
-	unsigned char plus, unhashed, is_root, h_plus, h_nfs, tmpfile;
-	struct inode *h_inode, *h_cached_inode;
-	struct dentry *h_dentry;
-	struct qstr *name, *h_name;
-
-	err = 0;
-	plus = 0;
-	mode = 0;
-	ibs = -1;
-	ibe = -1;
-	unhashed = !!d_unhashed(dentry);
-	is_root = !!IS_ROOT(dentry);
-	name = &dentry->d_name;
-	tmpfile = au_di(dentry)->di_tmpfile;
-
-	/*
-	 * Theoretically, REVAL test should be unnecessary in case of
-	 * {FS,I}NOTIFY.
-	 * But {fs,i}notify doesn't fire some necessary events,
-	 *	IN_ATTRIB for atime/nlink/pageio
-	 * Let's do REVAL test too.
-	 */
-	if (do_udba && inode) {
-		mode = (inode->i_mode & S_IFMT);
-		plus = (inode->i_nlink > 0);
-		ibs = au_ibstart(inode);
-		ibe = au_ibend(inode);
-	}
-
-	bstart = au_dbstart(dentry);
-	btail = bstart;
-	if (inode && S_ISDIR(inode->i_mode))
-		btail = au_dbtaildir(dentry);
-	for (bindex = bstart; bindex <= btail; bindex++) {
-		h_dentry = au_h_dptr(dentry, bindex);
-		if (!h_dentry)
-			continue;
-
-		AuDbg("b%d, %pd\n", bindex, h_dentry);
-		h_nfs = !!au_test_nfs(h_dentry->d_sb);
-		spin_lock(&h_dentry->d_lock);
-		h_name = &h_dentry->d_name;
-		if (unlikely(do_udba
-			     && !is_root
-			     && ((!h_nfs
-				  && (unhashed != !!d_unhashed(h_dentry)
-				      || (!tmpfile
-					  && !au_qstreq(name, h_name))
-					  ))
-				 || (h_nfs
-				     && !(flags & LOOKUP_OPEN)
-				     && (h_dentry->d_flags
-					 & DCACHE_NFSFS_RENAMED)))
-			    )) {
-			int h_unhashed;
-
-			h_unhashed = d_unhashed(h_dentry);
-			spin_unlock(&h_dentry->d_lock);
-			AuDbg("unhash 0x%x 0x%x, %pd %pd\n",
-			      unhashed, h_unhashed, dentry, h_dentry);
-			goto err;
-		}
-		spin_unlock(&h_dentry->d_lock);
-
-		err = au_do_h_d_reval(h_dentry, flags, dentry, bindex);
-		if (unlikely(err))
-			/* do not goto err, to keep the errno */
-			break;
-
-		/* todo: plink too? */
-		if (!do_udba)
-			continue;
-
-		/* UDBA tests */
-		if (unlikely(!!inode != d_is_positive(h_dentry)))
-			goto err;
-
-		h_inode = NULL;
-		if (d_is_positive(h_dentry))
-			h_inode = d_inode(h_dentry);
-		h_plus = plus;
-		h_mode = mode;
-		h_cached_inode = h_inode;
-		if (h_inode) {
-			h_mode = (h_inode->i_mode & S_IFMT);
-			h_plus = (h_inode->i_nlink > 0);
-		}
-		if (inode && ibs <= bindex && bindex <= ibe)
-			h_cached_inode = au_h_iptr(inode, bindex);
-
-		if (!h_nfs) {
-			if (unlikely(plus != h_plus && !tmpfile))
-				goto err;
-		} else {
-			if (unlikely(!(h_dentry->d_flags & DCACHE_NFSFS_RENAMED)
-				     && !is_root
-				     && !IS_ROOT(h_dentry)
-				     && unhashed != d_unhashed(h_dentry)))
-				goto err;
-		}
-		if (unlikely(mode != h_mode
-			     || h_cached_inode != h_inode))
-			goto err;
-		continue;
-
-err:
-		err = -EINVAL;
-		break;
-	}
-
-	AuTraceErr(err);
-	return err;
-}
-
-/* todo: consolidate with do_refresh() and au_reval_for_attr() */
-static int simple_reval_dpath(struct dentry *dentry, unsigned int sigen)
-{
-	int err;
-	struct dentry *parent;
-
-	if (!au_digen_test(dentry, sigen))
-		return 0;
-
-	parent = dget_parent(dentry);
-	di_read_lock_parent(parent, AuLock_IR);
-	AuDebugOn(au_digen_test(parent, sigen));
-	au_dbg_verify_gen(parent, sigen);
-	err = au_refresh_dentry(dentry, parent);
-	di_read_unlock(parent, AuLock_IR);
-	dput(parent);
-	AuTraceErr(err);
-	return err;
-}
-
-int au_reval_dpath(struct dentry *dentry, unsigned int sigen)
-{
-	int err;
-	struct dentry *d, *parent;
-
-	if (!au_ftest_si(au_sbi(dentry->d_sb), FAILED_REFRESH_DIR))
-		return simple_reval_dpath(dentry, sigen);
-
-	/* slow loop, keep it simple and stupid */
-	/* cf: au_cpup_dirs() */
-	err = 0;
-	parent = NULL;
-	while (au_digen_test(dentry, sigen)) {
-		d = dentry;
-		while (1) {
-			dput(parent);
-			parent = dget_parent(d);
-			if (!au_digen_test(parent, sigen))
-				break;
-			d = parent;
-		}
-
-		if (d != dentry)
-			di_write_lock_child2(d);
-
-		/* someone might update our dentry while we were sleeping */
-		if (au_digen_test(d, sigen)) {
-			/*
-			 * todo: consolidate with simple_reval_dpath(),
-			 * do_refresh() and au_reval_for_attr().
-			 */
-			di_read_lock_parent(parent, AuLock_IR);
-			err = au_refresh_dentry(d, parent);
-			di_read_unlock(parent, AuLock_IR);
-		}
-
-		if (d != dentry)
-			di_write_unlock(d);
-		dput(parent);
-		if (unlikely(err))
-			break;
-	}
-
-	return err;
-}
-
-/*
- * if valid returns 1, otherwise 0.
- */
-static int aufs_d_revalidate(struct dentry *dentry, unsigned int flags)
-{
-	int valid, err;
-	unsigned int sigen;
-	unsigned char do_udba;
-	struct super_block *sb;
-	struct inode *inode;
-
-	/* todo: support rcu-walk? */
-	if (flags & LOOKUP_RCU)
-		return -ECHILD;
-
-	valid = 0;
-	if (unlikely(!au_di(dentry)))
-		goto out;
-
-	valid = 1;
-	sb = dentry->d_sb;
-	/*
-	 * todo: very ugly
-	 * i_mutex of parent dir may be held,
-	 * but we should not return 'invalid' due to busy.
-	 */
-	err = aufs_read_lock(dentry, AuLock_FLUSH | AuLock_DW | AuLock_NOPLM);
-	if (unlikely(err)) {
-		valid = err;
-		AuTraceErr(err);
-		goto out;
-	}
-	inode = NULL;
-	if (d_really_is_positive(dentry))
-		inode = d_inode(dentry);
-	if (unlikely(inode && is_bad_inode(inode))) {
-		err = -EINVAL;
-		AuTraceErr(err);
-		goto out_dgrade;
-	}
-	if (unlikely(au_dbrange_test(dentry))) {
-		err = -EINVAL;
-		AuTraceErr(err);
-		goto out_dgrade;
-	}
-
-	sigen = au_sigen(sb);
-	if (au_digen_test(dentry, sigen)) {
-		AuDebugOn(IS_ROOT(dentry));
-		err = au_reval_dpath(dentry, sigen);
-		if (unlikely(err)) {
-			AuTraceErr(err);
-			goto out_dgrade;
-		}
-	}
-	di_downgrade_lock(dentry, AuLock_IR);
-
-	err = -EINVAL;
-	if (!(flags & (LOOKUP_OPEN | LOOKUP_EMPTY))
-	    && inode
-	    && !(inode->i_state && I_LINKABLE)
-	    && (IS_DEADDIR(inode) || !inode->i_nlink)) {
-		AuTraceErr(err);
-		goto out_inval;
-	}
-
-	do_udba = !au_opt_test(au_mntflags(sb), UDBA_NONE);
-	if (do_udba && inode) {
-		aufs_bindex_t bstart = au_ibstart(inode);
-		struct inode *h_inode;
-
-		if (bstart >= 0) {
-			h_inode = au_h_iptr(inode, bstart);
-			if (h_inode && au_test_higen(inode, h_inode)) {
-				AuTraceErr(err);
-				goto out_inval;
-			}
-		}
-	}
-
-	err = h_d_revalidate(dentry, inode, flags, do_udba);
-	if (unlikely(!err && do_udba && au_dbstart(dentry) < 0)) {
-		err = -EIO;
-		AuDbg("both of real entry and whiteout found, %p, err %d\n",
-		      dentry, err);
-	}
-	goto out_inval;
-
-out_dgrade:
-	di_downgrade_lock(dentry, AuLock_IR);
-out_inval:
-	aufs_read_unlock(dentry, AuLock_IR);
-	AuTraceErr(err);
-	valid = !err;
-out:
-	if (!valid) {
-		AuDbg("%pd invalid, %d\n", dentry, valid);
-		d_drop(dentry);
-	}
-	return valid;
-}
-
-static void aufs_d_release(struct dentry *dentry)
-{
-	if (au_di(dentry)) {
-		au_di_fin(dentry);
-		au_hn_di_reinit(dentry);
-	}
-}
-
-const struct dentry_operations aufs_dop = {
-	.d_revalidate		= aufs_d_revalidate,
-	.d_weak_revalidate	= aufs_d_revalidate,
-	.d_release		= aufs_d_release
-};
-
-/* aufs_dop without d_revalidate */
-const struct dentry_operations aufs_dop_noreval = {
-	.d_release		= aufs_d_release
-};