ocfs2: Hook rest of the file system into dentry locking API

Actually replace the vote calls with the new dentry operations. Make any
necessary adjustments to get the scheme to work.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

4 files changed, 94 insertions, 41 deletions

diff --git a/fs/ocfs2/cluster/tcp_internal.h b/fs/ocfs2/cluster/tcp_internal.h
index ff9e2e2..da42b51 100644
--- a/fs/ocfs2/cluster/tcp_internal.h
+++ b/fs/ocfs2/cluster/tcp_internal.h
@@ -44,11 +44,14 @@
  * locking semantics of the file system using the protocol.  It should 
  * be somewhere else, I'm sure, but right now it isn't.
  *
+ * New in version 3:
+ * 	- Replace dentry votes with a cluster lock
+ *
  * New in version 2:
  * 	- full 64 bit i_size in the metadata lock lvbs
  * 	- introduction of "rw" lock and pushing meta/data locking down
  */
-#define O2NET_PROTOCOL_VERSION 2ULL
+#define O2NET_PROTOCOL_VERSION 3ULL
 struct o2net_handshake {
 	__be64	protocol_version;
 	__be64	connector_id;
diff --git a/fs/ocfs2/export.c b/fs/ocfs2/export.c
index ec55ab3..ffcd797 100644
--- a/fs/ocfs2/export.c
+++ b/fs/ocfs2/export.c
@@ -33,6 +33,7 @@
 
 #include "dir.h"
 #include "dlmglue.h"
+#include "dcache.h"
 #include "export.h"
 #include "inode.h"
 
@@ -77,6 +78,7 @@ static struct dentry *ocfs2_get_dentry(struct super_block *sb, void *vobjp)
 		mlog_errno(-ENOMEM);
 		return ERR_PTR(-ENOMEM);
 	}
+	result->d_op = &ocfs2_dentry_ops;
 
 	mlog_exit_ptr(result);
 	return result;
@@ -127,6 +129,8 @@ static struct dentry *ocfs2_get_parent(struct dentry *child)
 		parent = ERR_PTR(-ENOMEM);
 	}
 
+	parent->d_op = &ocfs2_dentry_ops;
+
 bail_unlock:
 	ocfs2_meta_unlock(dir, 0);
 
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 7bcf691..66ca7a8 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -1025,12 +1025,10 @@ void ocfs2_drop_inode(struct inode *inode)
 	/* Testing ip_orphaned_slot here wouldn't work because we may
 	 * not have gotten a delete_inode vote from any other nodes
 	 * yet. */
-	if (oi->ip_flags & OCFS2_INODE_MAYBE_ORPHANED) {
-		mlog(0, "Inode was orphaned on another node, clearing nlink.\n");
-		inode->i_nlink = 0;
-	}
-
-	generic_drop_inode(inode);
+	if (oi->ip_flags & OCFS2_INODE_MAYBE_ORPHANED)
+		generic_delete_inode(inode);
+	else
+		generic_drop_inode(inode);
 
 	mlog_exit_void();
 }
diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 0d3e939..5a942e0 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -199,10 +199,32 @@ static struct dentry *ocfs2_lookup(struct inode *dir, struct dentry *dentry,
 	spin_unlock(&oi->ip_lock);
 
 bail_add:
-
 	dentry->d_op = &ocfs2_dentry_ops;
 	ret = d_splice_alias(inode, dentry);
 
+	if (inode) {
+		/*
+		 * If d_splice_alias() finds a DCACHE_DISCONNECTED
+		 * dentry, it will d_move() it on top of ourse. The
+		 * return value will indicate this however, so in
+		 * those cases, we switch them around for the locking
+		 * code.
+		 *
+		 * NOTE: This dentry already has ->d_op set from
+		 * ocfs2_get_parent() and ocfs2_get_dentry()
+		 */
+		if (ret)
+			dentry = ret;
+
+		status = ocfs2_dentry_attach_lock(dentry, inode,
+						  OCFS2_I(dir)->ip_blkno, 0);
+		if (status) {
+			mlog_errno(status);
+			ret = ERR_PTR(status);
+			goto bail_unlock;
+		}
+	}
+
 bail_unlock:
 	/* Don't drop the cluster lock until *after* the d_add --
 	 * unlink on another node will message us to remove that
@@ -418,6 +440,13 @@ static int ocfs2_mknod(struct inode *dir,
 		goto leave;
 	}
 
+	status = ocfs2_dentry_attach_lock(dentry, inode,
+					  OCFS2_I(dir)->ip_blkno, 1);
+	if (status) {
+		mlog_errno(status);
+		goto leave;
+	}
+
 	insert_inode_hash(inode);
 	dentry->d_op = &ocfs2_dentry_ops;
 	d_instantiate(dentry, inode);
@@ -725,6 +754,13 @@ static int ocfs2_link(struct dentry *old_dentry,
 		goto bail;
 	}
 
+	err = ocfs2_dentry_attach_lock(dentry, inode, OCFS2_I(dir)->ip_blkno,
+				       0);
+	if (err) {
+		mlog_errno(err);
+		goto bail;
+	}
+
 	atomic_inc(&inode->i_count);
 	dentry->d_op = &ocfs2_dentry_ops;
 	d_instantiate(dentry, inode);
@@ -743,6 +779,23 @@ bail:
 	return err;
 }
 
+/*
+ * Takes and drops an exclusive lock on the given dentry. This will
+ * force other nodes to drop it.
+ */
+static int ocfs2_remote_dentry_delete(struct dentry *dentry)
+{
+	int ret;
+
+	ret = ocfs2_dentry_lock(dentry, 1);
+	if (ret)
+		mlog_errno(ret);
+	else
+		ocfs2_dentry_unlock(dentry, 1);
+
+	return ret;
+}
+
 static int ocfs2_unlink(struct inode *dir,
 			struct dentry *dentry)
 {
@@ -832,8 +885,7 @@ static int ocfs2_unlink(struct inode *dir,
 	else
 		inode->i_nlink--;
 
-	status = ocfs2_request_unlink_vote(inode, dentry,
-					   (unsigned int) inode->i_nlink);
+	status = ocfs2_remote_dentry_delete(dentry);
 	if (status < 0) {
 		/* This vote should succeed under all normal
 		 * circumstances. */
@@ -1019,7 +1071,6 @@ static int ocfs2_rename(struct inode *old_dir,
 	struct buffer_head *old_inode_de_bh = NULL; // if old_dentry is a dir,
 						    // this is the 1st dirent bh
 	nlink_t old_dir_nlink = old_dir->i_nlink, new_dir_nlink = new_dir->i_nlink;
-	unsigned int links_count;
 
 	/* At some point it might be nice to break this function up a
 	 * bit. */
@@ -1093,23 +1144,26 @@ static int ocfs2_rename(struct inode *old_dir,
 		}
 	}
 
-	if (S_ISDIR(old_inode->i_mode)) {
-		/* Directories actually require metadata updates to
-		 * the directory info so we can't get away with not
-		 * doing node locking on it. */
-		status = ocfs2_meta_lock(old_inode, handle, NULL, 1);
-		if (status < 0) {
-			if (status != -ENOENT)
-				mlog_errno(status);
-			goto bail;
-		}
-
-		status = ocfs2_request_rename_vote(old_inode, old_dentry);
-		if (status < 0) {
+	/*
+	 * Though we don't require an inode meta data update if
+	 * old_inode is not a directory, we lock anyway here to ensure
+	 * the vote thread on other nodes won't have to concurrently
+	 * downconvert the inode and the dentry locks.
+	 */
+	status = ocfs2_meta_lock(old_inode, handle, NULL, 1);
+	if (status < 0) {
+		if (status != -ENOENT)
 			mlog_errno(status);
-			goto bail;
-		}
+		goto bail;
+	}
+
+	status = ocfs2_remote_dentry_delete(old_dentry);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
 
+	if (S_ISDIR(old_inode->i_mode)) {
 		status = -EIO;
 		old_inode_de_bh = ocfs2_bread(old_inode, 0, &status, 0);
 		if (!old_inode_de_bh)
@@ -1123,14 +1177,6 @@ static int ocfs2_rename(struct inode *old_dir,
 		if (!new_inode && new_dir!=old_dir &&
 		    new_dir->i_nlink >= OCFS2_LINK_MAX)
 			goto bail;
-	} else {
-		/* Ah, the simple case - we're a file so just send a
-		 * message. */
-		status = ocfs2_request_rename_vote(old_inode, old_dentry);
-		if (status < 0) {
-			mlog_errno(status);
-			goto bail;
-		}
 	}
 
 	status = -ENOENT;
@@ -1202,13 +1248,7 @@ static int ocfs2_rename(struct inode *old_dir,
 			goto bail;
 		}
 
-		if (S_ISDIR(new_inode->i_mode))
-			links_count = 0;
-		else
-			links_count = (unsigned int) (new_inode->i_nlink - 1);
-
-		status = ocfs2_request_unlink_vote(new_inode, new_dentry,
-						   links_count);
+		status = ocfs2_remote_dentry_delete(new_dentry);
 		if (status < 0) {
 			mlog_errno(status);
 			goto bail;
@@ -1387,6 +1427,7 @@ static int ocfs2_rename(struct inode *old_dir,
 		}
 	}
 
+	ocfs2_dentry_move(old_dentry, new_dentry, old_dir, new_dir);
 	status = 0;
 bail:
 	if (rename_lock)
@@ -1675,6 +1716,13 @@ static int ocfs2_symlink(struct inode *dir,
 		goto bail;
 	}
 
+	status = ocfs2_dentry_attach_lock(dentry, inode,
+					  OCFS2_I(dir)->ip_blkno, 1);
+	if (status) {
+		mlog_errno(status);
+		goto bail;
+	}
+
 	insert_inode_hash(inode);
 	dentry->d_op = &ocfs2_dentry_ops;
 	d_instantiate(dentry, inode);