From: Rachita Kothiyal <rachita@dewey.fsl.cs.sunysb.edu>
Date: Fri, 29 Feb 2008 16:59:31 +0000 (-0500)
Subject: Unionfs: extend dentry branch configuration lock in open
X-Git-Url: https://git.fsl.cs.stonybrook.edu/?a=commitdiff_plain;h=bf1e8bfee69d50e7331d6f41f53614e3afbcdabb;p=unionfs-odf.git

Unionfs: extend dentry branch configuration lock in open

Dentry branch configuration "info node" lock should extend to calls to
copy_attr_times.

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
---

diff --git a/fs/unionfs/commonfops.c b/fs/unionfs/commonfops.c
index 8eb4e84340..68023164de 100644
--- a/fs/unionfs/commonfops.c
+++ b/fs/unionfs/commonfops.c
@@ -603,11 +603,22 @@ int unionfs_open(struct inode *inode, struct file *file)
 {
 	int err = 0;
 	struct file *lower_file = NULL;
-	struct dentry *dentry = NULL;
+	struct dentry *dentry = file->f_path.dentry;
 	int bindex = 0, bstart = 0, bend = 0;
 	int size;
 
 	unionfs_read_lock(inode->i_sb, UNIONFS_SMUTEX_PARENT);
+	unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);
+
+	/*
+	 * With nfs exporting we cannot get a disconnected dentry here,
+	 * since we already connect it in unionfs_get_parent.  This check
+	 * can probably be removed after sufficient testing.
+	 */
+	if (dentry->d_flags & DCACHE_DISCONNECTED) {
+		err = -ESTALE;
+		goto out;
+	}
 
 	file->private_data =
 		kzalloc(sizeof(struct unionfs_file_info), GFP_KERNEL);
@@ -633,18 +644,6 @@ int unionfs_open(struct inode *inode, struct file *file)
 		goto out;
 	}
 
-	dentry = file->f_path.dentry;
-
-	/*
-	 * With nfs exporting we cannot get a disconnected dentry here,
-	 * since we already connect it in unionfs_get_parent.  This check
-	 * can probably be removed after sufficient testing.
-	 */
-	if (dentry->d_flags & DCACHE_DISCONNECTED) {
-		err = -ESTALE;
-		goto out;
-	}
-	unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);
 
 	bstart = fbstart(file) = dbstart(dentry);
 	bend = fbend(file) = dbend(dentry);
@@ -665,15 +664,12 @@ int unionfs_open(struct inode *inode, struct file *file)
 			if (!lower_file)
 				continue;
 
-			branchput(file->f_path.dentry->d_sb, bindex);
+			branchput(dentry->d_sb, bindex);
 			/* fput calls dput for lower_dentry */
 			fput(lower_file);
 		}
 	}
 
-	/* XXX: should this unlock be moved to the function bottom? */
-	unionfs_unlock_dentry(dentry);
-
 out:
 	if (err) {
 		kfree(UNIONFS_F(file)->lower_files);
@@ -682,12 +678,11 @@ out:
 	}
 out_nofree:
 	if (!err) {
-		dentry = file->f_path.dentry;
-		unionfs_copy_attr_times(dentry->d_parent->d_inode);
 		unionfs_copy_attr_times(inode);
 		unionfs_check_file(file);
 		unionfs_check_inode(inode);
 	}
+	unionfs_unlock_dentry(dentry);
 	unionfs_read_unlock(inode->i_sb);
 	return err;
 }