1 files changed, 675 insertions, 0 deletions

diff --git a/drivers/staging/lustre/lustre/llite/dcache.c b/drivers/staging/lustre/lustre/llite/dcache.c
new file mode 100644
index 000000000000..7d6abfff9740
--- /dev/null
+++ b/drivers/staging/lustre/lustre/llite/dcache.c
@@ -0,0 +1,675 @@
+/*
+ * GPL HEADER START
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * 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 version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see
+ * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
+ */
+
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/quotaops.h>
+
+#define DEBUG_SUBSYSTEM S_LLITE
+
+#include <obd_support.h>
+#include <lustre_lite.h>
+#include <lustre/lustre_idl.h>
+#include <lustre_dlm.h>
+
+#include "llite_internal.h"
+
+static void free_dentry_data(struct rcu_head *head)
+{
+	struct ll_dentry_data *lld;
+
+	lld = container_of(head, struct ll_dentry_data, lld_rcu_head);
+	OBD_FREE_PTR(lld);
+}
+
+/* should NOT be called with the dcache lock, see fs/dcache.c */
+static void ll_release(struct dentry *de)
+{
+	struct ll_dentry_data *lld;
+	ENTRY;
+	LASSERT(de != NULL);
+	lld = ll_d2d(de);
+	if (lld == NULL) /* NFS copies the de->d_op methods (bug 4655) */
+		RETURN_EXIT;
+
+	if (lld->lld_it) {
+		ll_intent_release(lld->lld_it);
+		OBD_FREE(lld->lld_it, sizeof(*lld->lld_it));
+	}
+	LASSERT(lld->lld_cwd_count == 0);
+	LASSERT(lld->lld_mnt_count == 0);
+	de->d_fsdata = NULL;
+	call_rcu(&lld->lld_rcu_head, free_dentry_data);
+
+	EXIT;
+}
+
+/* Compare if two dentries are the same.  Don't match if the existing dentry
+ * is marked invalid.  Returns 1 if different, 0 if the same.
+ *
+ * This avoids a race where ll_lookup_it() instantiates a dentry, but we get
+ * an AST before calling d_revalidate_it().  The dentry still exists (marked
+ * INVALID) so d_lookup() matches it, but we have no lock on it (so
+ * lock_match() fails) and we spin around real_lookup(). */
+int ll_dcompare(const struct dentry *parent, const struct inode *pinode,
+		const struct dentry *dentry, const struct inode *inode,
+		unsigned int len, const char *str, const struct qstr *name)
+{
+	ENTRY;
+
+	if (len != name->len)
+		RETURN(1);
+
+	if (memcmp(str, name->name, len))
+		RETURN(1);
+
+	CDEBUG(D_DENTRY, "found name %.*s(%p) flags %#x refc %d\n",
+	       name->len, name->name, dentry, dentry->d_flags,
+	       d_refcount(dentry));
+
+	/* mountpoint is always valid */
+	if (d_mountpoint((struct dentry *)dentry))
+		RETURN(0);
+
+	if (d_lustre_invalid(dentry))
+		RETURN(1);
+
+	RETURN(0);
+}
+
+static inline int return_if_equal(struct ldlm_lock *lock, void *data)
+{
+	if ((lock->l_flags &
+	     (LDLM_FL_CANCELING | LDLM_FL_DISCARD_DATA)) ==
+	    (LDLM_FL_CANCELING | LDLM_FL_DISCARD_DATA))
+		return LDLM_ITER_CONTINUE;
+	return LDLM_ITER_STOP;
+}
+
+/* find any ldlm lock of the inode in mdc and lov
+ * return 0    not find
+ *	1    find one
+ *      < 0    error */
+static int find_cbdata(struct inode *inode)
+{
+	struct ll_sb_info *sbi = ll_i2sbi(inode);
+	struct lov_stripe_md *lsm;
+	int rc = 0;
+	ENTRY;
+
+	LASSERT(inode);
+	rc = md_find_cbdata(sbi->ll_md_exp, ll_inode2fid(inode),
+			    return_if_equal, NULL);
+	if (rc != 0)
+		 RETURN(rc);
+
+	lsm = ccc_inode_lsm_get(inode);
+	if (lsm == NULL)
+		RETURN(rc);
+
+	rc = obd_find_cbdata(sbi->ll_dt_exp, lsm, return_if_equal, NULL);
+	ccc_inode_lsm_put(inode, lsm);
+
+	RETURN(rc);
+}
+
+/**
+ * Called when last reference to a dentry is dropped and dcache wants to know
+ * whether or not it should cache it:
+ * - return 1 to delete the dentry immediately
+ * - return 0 to cache the dentry
+ * Should NOT be called with the dcache lock, see fs/dcache.c
+ */
+static int ll_ddelete(const struct dentry *de)
+{
+	ENTRY;
+	LASSERT(de);
+
+	CDEBUG(D_DENTRY, "%s dentry %.*s (%p, parent %p, inode %p) %s%s\n",
+	       d_lustre_invalid((struct dentry *)de) ? "deleting" : "keeping",
+	       de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
+	       d_unhashed((struct dentry *)de) ? "" : "hashed,",
+	       list_empty(&de->d_subdirs) ? "" : "subdirs");
+
+	/* kernel >= 2.6.38 last refcount is decreased after this function. */
+	LASSERT(d_refcount(de) == 1);
+
+	/* Disable this piece of code temproarily because this is called
+	 * inside dcache_lock so it's not appropriate to do lots of work
+	 * here. ATTENTION: Before this piece of code enabling, LU-2487 must be
+	 * resolved. */
+#if 0
+	/* if not ldlm lock for this inode, set i_nlink to 0 so that
+	 * this inode can be recycled later b=20433 */
+	if (de->d_inode && !find_cbdata(de->d_inode))
+		clear_nlink(de->d_inode);
+#endif
+
+	if (d_lustre_invalid((struct dentry *)de))
+		RETURN(1);
+	RETURN(0);
+}
+
+static int ll_set_dd(struct dentry *de)
+{
+	ENTRY;
+	LASSERT(de != NULL);
+
+	CDEBUG(D_DENTRY, "ldd on dentry %.*s (%p) parent %p inode %p refc %d\n",
+		de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
+		d_refcount(de));
+
+	if (de->d_fsdata == NULL) {
+		struct ll_dentry_data *lld;
+
+		OBD_ALLOC_PTR(lld);
+		if (likely(lld != NULL)) {
+			spin_lock(&de->d_lock);
+			if (likely(de->d_fsdata == NULL))
+				de->d_fsdata = lld;
+			else
+				OBD_FREE_PTR(lld);
+			spin_unlock(&de->d_lock);
+		} else {
+			RETURN(-ENOMEM);
+		}
+	}
+
+	RETURN(0);
+}
+
+int ll_dops_init(struct dentry *de, int block, int init_sa)
+{
+	struct ll_dentry_data *lld = ll_d2d(de);
+	int rc = 0;
+
+	if (lld == NULL && block != 0) {
+		rc = ll_set_dd(de);
+		if (rc)
+			return rc;
+
+		lld = ll_d2d(de);
+	}
+
+	if (lld != NULL && init_sa != 0)
+		lld->lld_sa_generation = 0;
+
+	/* kernel >= 2.6.38 d_op is set in d_alloc() */
+	LASSERT(de->d_op == &ll_d_ops);
+	return rc;
+}
+
+void ll_intent_drop_lock(struct lookup_intent *it)
+{
+	if (it->it_op && it->d.lustre.it_lock_mode) {
+		struct lustre_handle handle;
+
+		handle.cookie = it->d.lustre.it_lock_handle;
+
+		CDEBUG(D_DLMTRACE, "releasing lock with cookie "LPX64
+		       " from it %p\n", handle.cookie, it);
+		ldlm_lock_decref(&handle, it->d.lustre.it_lock_mode);
+
+		/* bug 494: intent_release may be called multiple times, from
+		 * this thread and we don't want to double-decref this lock */
+		it->d.lustre.it_lock_mode = 0;
+		if (it->d.lustre.it_remote_lock_mode != 0) {
+			handle.cookie = it->d.lustre.it_remote_lock_handle;
+
+			CDEBUG(D_DLMTRACE, "releasing remote lock with cookie"
+			       LPX64" from it %p\n", handle.cookie, it);
+			ldlm_lock_decref(&handle,
+					 it->d.lustre.it_remote_lock_mode);
+			it->d.lustre.it_remote_lock_mode = 0;
+		}
+	}
+}
+
+void ll_intent_release(struct lookup_intent *it)
+{
+	ENTRY;
+
+	CDEBUG(D_INFO, "intent %p released\n", it);
+	ll_intent_drop_lock(it);
+	/* We are still holding extra reference on a request, need to free it */
+	if (it_disposition(it, DISP_ENQ_OPEN_REF))
+		 ptlrpc_req_finished(it->d.lustre.it_data); /* ll_file_open */
+	if (it_disposition(it, DISP_ENQ_CREATE_REF)) /* create rec */
+		ptlrpc_req_finished(it->d.lustre.it_data);
+	if (it_disposition(it, DISP_ENQ_COMPLETE)) /* saved req from revalidate
+						    * to lookup */
+		ptlrpc_req_finished(it->d.lustre.it_data);
+
+	it->d.lustre.it_disposition = 0;
+	it->d.lustre.it_data = NULL;
+	EXIT;
+}
+
+void ll_invalidate_aliases(struct inode *inode)
+{
+	struct dentry *dentry;
+	struct ll_d_hlist_node *p;
+	ENTRY;
+
+	LASSERT(inode != NULL);
+
+	CDEBUG(D_INODE, "marking dentries for ino %lu/%u(%p) invalid\n",
+	       inode->i_ino, inode->i_generation, inode);
+
+	ll_lock_dcache(inode);
+	ll_d_hlist_for_each_entry(dentry, p, &inode->i_dentry, d_alias) {
+		CDEBUG(D_DENTRY, "dentry in drop %.*s (%p) parent %p "
+		       "inode %p flags %d\n", dentry->d_name.len,
+		       dentry->d_name.name, dentry, dentry->d_parent,
+		       dentry->d_inode, dentry->d_flags);
+
+		if (dentry->d_name.len == 1 && dentry->d_name.name[0] == '/') {
+			CERROR("called on root (?) dentry=%p, inode=%p "
+			       "ino=%lu\n", dentry, inode, inode->i_ino);
+			lustre_dump_dentry(dentry, 1);
+			libcfs_debug_dumpstack(NULL);
+		}
+
+		d_lustre_invalidate(dentry, 0);
+	}
+	ll_unlock_dcache(inode);
+
+	EXIT;
+}
+
+int ll_revalidate_it_finish(struct ptlrpc_request *request,
+			    struct lookup_intent *it,
+			    struct dentry *de)
+{
+	int rc = 0;
+	ENTRY;
+
+	if (!request)
+		RETURN(0);
+
+	if (it_disposition(it, DISP_LOOKUP_NEG))
+		RETURN(-ENOENT);
+
+	rc = ll_prep_inode(&de->d_inode, request, NULL, it);
+
+	RETURN(rc);
+}
+
+void ll_lookup_finish_locks(struct lookup_intent *it, struct dentry *dentry)
+{
+	LASSERT(it != NULL);
+	LASSERT(dentry != NULL);
+
+	if (it->d.lustre.it_lock_mode && dentry->d_inode != NULL) {
+		struct inode *inode = dentry->d_inode;
+		struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode);
+
+		CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
+		       inode, inode->i_ino, inode->i_generation);
+		ll_set_lock_data(sbi->ll_md_exp, inode, it, NULL);
+	}
+
+	/* drop lookup or getattr locks immediately */
+	if (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR) {
+		/* on 2.6 there are situation when several lookups and
+		 * revalidations may be requested during single operation.
+		 * therefore, we don't release intent here -bzzz */
+		ll_intent_drop_lock(it);
+	}
+}
+
+void ll_frob_intent(struct lookup_intent **itp, struct lookup_intent *deft)
+{
+	struct lookup_intent *it = *itp;
+
+	if (!it || it->it_op == IT_GETXATTR)
+		it = *itp = deft;
+
+}
+
+int ll_revalidate_it(struct dentry *de, int lookup_flags,
+		     struct lookup_intent *it)
+{
+	struct md_op_data *op_data;
+	struct ptlrpc_request *req = NULL;
+	struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
+	struct obd_export *exp;
+	struct inode *parent = de->d_parent->d_inode;
+	int rc;
+
+	ENTRY;
+	CDEBUG(D_VFSTRACE, "VFS Op:name=%s,intent=%s\n", de->d_name.name,
+	       LL_IT2STR(it));
+
+	if (de->d_inode == NULL) {
+		__u64 ibits;
+
+		/* We can only use negative dentries if this is stat or lookup,
+		   for opens and stuff we do need to query server. */
+		/* If there is IT_CREAT in intent op set, then we must throw
+		   away this negative dentry and actually do the request to
+		   kernel to create whatever needs to be created (if possible)*/
+		if (it && (it->it_op & IT_CREAT))
+			RETURN(0);
+
+		if (d_lustre_invalid(de))
+			RETURN(0);
+
+		ibits = MDS_INODELOCK_UPDATE;
+		rc = ll_have_md_lock(parent, &ibits, LCK_MINMODE);
+		GOTO(out_sa, rc);
+	}
+
+	/* Never execute intents for mount points.
+	 * Attributes will be fixed up in ll_inode_revalidate_it */
+	if (d_mountpoint(de))
+		GOTO(out_sa, rc = 1);
+
+	/* need to get attributes in case root got changed from other client */
+	if (de == de->d_sb->s_root) {
+		rc = __ll_inode_revalidate_it(de, it, MDS_INODELOCK_LOOKUP);
+		if (rc == 0)
+			rc = 1;
+		GOTO(out_sa, rc);
+	}
+
+	exp = ll_i2mdexp(de->d_inode);
+
+	OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
+	ll_frob_intent(&it, &lookup_it);
+	LASSERT(it);
+
+	if (it->it_op == IT_LOOKUP && !d_lustre_invalid(de))
+		RETURN(1);
+
+	if (it->it_op == IT_OPEN) {
+		struct inode *inode = de->d_inode;
+		struct ll_inode_info *lli = ll_i2info(inode);
+		struct obd_client_handle **och_p;
+		__u64 *och_usecount;
+		__u64 ibits;
+
+		/*
+		 * We used to check for MDS_INODELOCK_OPEN here, but in fact
+		 * just having LOOKUP lock is enough to justify inode is the
+		 * same. And if inode is the same and we have suitable
+		 * openhandle, then there is no point in doing another OPEN RPC
+		 * just to throw away newly received openhandle.  There are no
+		 * security implications too, if file owner or access mode is
+		 * change, LOOKUP lock is revoked.
+		 */
+
+
+		if (it->it_flags & FMODE_WRITE) {
+			och_p = &lli->lli_mds_write_och;
+			och_usecount = &lli->lli_open_fd_write_count;
+		} else if (it->it_flags & FMODE_EXEC) {
+			och_p = &lli->lli_mds_exec_och;
+			och_usecount = &lli->lli_open_fd_exec_count;
+		} else {
+			och_p = &lli->lli_mds_read_och;
+			och_usecount = &lli->lli_open_fd_read_count;
+		}
+		/* Check for the proper lock. */
+		ibits = MDS_INODELOCK_LOOKUP;
+		if (!ll_have_md_lock(inode, &ibits, LCK_MINMODE))
+			goto do_lock;
+		mutex_lock(&lli->lli_och_mutex);
+		if (*och_p) { /* Everything is open already, do nothing */
+			/*(*och_usecount)++;  Do not let them steal our open
+			  handle from under us */
+			SET_BUT_UNUSED(och_usecount);
+			/* XXX The code above was my original idea, but in case
+			   we have the handle, but we cannot use it due to later
+			   checks (e.g. O_CREAT|O_EXCL flags set), nobody
+			   would decrement counter increased here. So we just
+			   hope the lock won't be invalidated in between. But
+			   if it would be, we'll reopen the open request to
+			   MDS later during file open path */
+			mutex_unlock(&lli->lli_och_mutex);
+			RETURN(1);
+		} else {
+			mutex_unlock(&lli->lli_och_mutex);
+		}
+	}
+
+	if (it->it_op == IT_GETATTR) {
+		rc = ll_statahead_enter(parent, &de, 0);
+		if (rc == 1)
+			goto mark;
+		else if (rc != -EAGAIN && rc != 0)
+			GOTO(out, rc = 0);
+	}
+
+do_lock:
+	op_data = ll_prep_md_op_data(NULL, parent, de->d_inode,
+				     de->d_name.name, de->d_name.len,
+				     0, LUSTRE_OPC_ANY, NULL);
+	if (IS_ERR(op_data))
+		RETURN(PTR_ERR(op_data));
+
+	if (!IS_POSIXACL(parent) || !exp_connect_umask(exp))
+		it->it_create_mode &= ~current_umask();
+	it->it_create_mode |= M_CHECK_STALE;
+	rc = md_intent_lock(exp, op_data, NULL, 0, it,
+			    lookup_flags,
+			    &req, ll_md_blocking_ast, 0);
+	it->it_create_mode &= ~M_CHECK_STALE;
+	ll_finish_md_op_data(op_data);
+
+	/* If req is NULL, then md_intent_lock only tried to do a lock match;
+	 * if all was well, it will return 1 if it found locks, 0 otherwise. */
+	if (req == NULL && rc >= 0) {
+		if (!rc)
+			goto do_lookup;
+		GOTO(out, rc);
+	}
+
+	if (rc < 0) {
+		if (rc != -ESTALE) {
+			CDEBUG(D_INFO, "ll_intent_lock: rc %d : it->it_status "
+			       "%d\n", rc, it->d.lustre.it_status);
+		}
+		GOTO(out, rc = 0);
+	}
+
+revalidate_finish:
+	rc = ll_revalidate_it_finish(req, it, de);
+	if (rc != 0) {
+		if (rc != -ESTALE && rc != -ENOENT)
+			ll_intent_release(it);
+		GOTO(out, rc = 0);
+	}
+
+	if ((it->it_op & IT_OPEN) && de->d_inode &&
+	    !S_ISREG(de->d_inode->i_mode) &&
+	    !S_ISDIR(de->d_inode->i_mode)) {
+		ll_release_openhandle(de, it);
+	}
+	rc = 1;
+
+out:
+	/* We do not free request as it may be reused during following lookup
+	 * (see comment in mdc/mdc_locks.c::mdc_intent_lock()), request will
+	 * be freed in ll_lookup_it or in ll_intent_release. But if
+	 * request was not completed, we need to free it. (bug 5154, 9903) */
+	if (req != NULL && !it_disposition(it, DISP_ENQ_COMPLETE))
+		ptlrpc_req_finished(req);
+	if (rc == 0) {
+		/* mdt may grant layout lock for the newly created file, so
+		 * release the lock to avoid leaking */
+		ll_intent_drop_lock(it);
+		ll_invalidate_aliases(de->d_inode);
+	} else {
+		__u64 bits = 0;
+		__u64 matched_bits = 0;
+
+		CDEBUG(D_DENTRY, "revalidated dentry %.*s (%p) parent %p "
+		       "inode %p refc %d\n", de->d_name.len,
+		       de->d_name.name, de, de->d_parent, de->d_inode,
+		       d_refcount(de));
+
+		ll_set_lock_data(exp, de->d_inode, it, &bits);
+
+		/* Note: We have to match both LOOKUP and PERM lock
+		 * here to make sure the dentry is valid and no one
+		 * changing the permission.
+		 * But if the client connects < 2.4 server, which will
+		 * only grant LOOKUP lock, so we can only Match LOOKUP
+		 * lock for old server */
+		if (exp_connect_flags(ll_i2mdexp(de->d_inode)) &&
+							OBD_CONNECT_LVB_TYPE)
+			matched_bits =
+				MDS_INODELOCK_LOOKUP | MDS_INODELOCK_PERM;
+		else
+			matched_bits = MDS_INODELOCK_LOOKUP;
+
+		if (((bits & matched_bits) == matched_bits) &&
+		    d_lustre_invalid(de))
+			d_lustre_revalidate(de);
+		ll_lookup_finish_locks(it, de);
+	}
+
+mark:
+	if (it != NULL && it->it_op == IT_GETATTR && rc > 0)
+		ll_statahead_mark(parent, de);
+	RETURN(rc);
+
+	/*
+	 * This part is here to combat evil-evil race in real_lookup on 2.6
+	 * kernels.  The race details are: We enter do_lookup() looking for some
+	 * name, there is nothing in dcache for this name yet and d_lookup()
+	 * returns NULL.  We proceed to real_lookup(), and while we do this,
+	 * another process does open on the same file we looking up (most simple
+	 * reproducer), open succeeds and the dentry is added. Now back to
+	 * us. In real_lookup() we do d_lookup() again and suddenly find the
+	 * dentry, so we call d_revalidate on it, but there is no lock, so
+	 * without this code we would return 0, but unpatched real_lookup just
+	 * returns -ENOENT in such a case instead of retrying the lookup. Once
+	 * this is dealt with in real_lookup(), all of this ugly mess can go and
+	 * we can just check locks in ->d_revalidate without doing any RPCs
+	 * ever.
+	 */
+do_lookup:
+	if (it != &lookup_it) {
+		/* MDS_INODELOCK_UPDATE needed for IT_GETATTR case. */
+		if (it->it_op == IT_GETATTR)
+			lookup_it.it_op = IT_GETATTR;
+		ll_lookup_finish_locks(it, de);
+		it = &lookup_it;
+	}
+
+	/* Do real lookup here. */
+	op_data = ll_prep_md_op_data(NULL, parent, NULL, de->d_name.name,
+				     de->d_name.len, 0, (it->it_op & IT_CREAT ?
+							 LUSTRE_OPC_CREATE :
+							 LUSTRE_OPC_ANY), NULL);
+	if (IS_ERR(op_data))
+		RETURN(PTR_ERR(op_data));
+
+	rc = md_intent_lock(exp, op_data, NULL, 0,  it, 0, &req,
+			    ll_md_blocking_ast, 0);
+	if (rc >= 0) {
+		struct mdt_body *mdt_body;
+		struct lu_fid fid = {.f_seq = 0, .f_oid = 0, .f_ver = 0};
+		mdt_body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
+
+		if (de->d_inode)
+			fid = *ll_inode2fid(de->d_inode);
+
+		/* see if we got same inode, if not - return error */
+		if (lu_fid_eq(&fid, &mdt_body->fid1)) {
+			ll_finish_md_op_data(op_data);
+			op_data = NULL;
+			goto revalidate_finish;
+		}
+		ll_intent_release(it);
+	}
+	ll_finish_md_op_data(op_data);
+	GOTO(out, rc = 0);
+
+out_sa:
+	/*
+	 * For rc == 1 case, should not return directly to prevent losing
+	 * statahead windows; for rc == 0 case, the "lookup" will be done later.
+	 */
+	if (it != NULL && it->it_op == IT_GETATTR && rc == 1)
+		ll_statahead_enter(parent, &de, 1);
+	goto mark;
+}
+
+/*
+ * Always trust cached dentries. Update statahead window if necessary.
+ */
+int ll_revalidate_nd(struct dentry *dentry, unsigned int flags)
+{
+	struct inode *parent = dentry->d_parent->d_inode;
+	int unplug = 0;
+
+	ENTRY;
+	CDEBUG(D_VFSTRACE, "VFS Op:name=%s,flags=%u\n",
+	       dentry->d_name.name, flags);
+
+	if (!(flags & (LOOKUP_PARENT|LOOKUP_OPEN|LOOKUP_CREATE)) &&
+	    ll_need_statahead(parent, dentry) > 0) {
+		if (flags & LOOKUP_RCU)
+			RETURN(-ECHILD);
+
+		if (dentry->d_inode == NULL)
+			unplug = 1;
+		do_statahead_enter(parent, &dentry, unplug);
+		ll_statahead_mark(parent, dentry);
+	}
+
+	RETURN(1);
+}
+
+
+void ll_d_iput(struct dentry *de, struct inode *inode)
+{
+	LASSERT(inode);
+	if (!find_cbdata(inode))
+		clear_nlink(inode);
+	iput(inode);
+}
+
+struct dentry_operations ll_d_ops = {
+	.d_revalidate = ll_revalidate_nd,
+	.d_release = ll_release,
+	.d_delete  = ll_ddelete,
+	.d_iput    = ll_d_iput,
+	.d_compare = ll_dcompare,
+};