linux-kernel - [PATCH v7 30/49] vfs: make rmdir retry on ESTALE errors

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Message-Id: <1349137018-21948-31-git-send-email-jlayton@redhat.com>
Date:	Mon,  1 Oct 2012 20:16:39 -0400
From:	Jeff Layton <jlayton@...hat.com>
To:	viro@...IV.linux.org.uk
Cc:	eparis@...hat.com, linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-audit@...hat.com
Subject: [PATCH v7 30/49] vfs: make rmdir retry on ESTALE errors

Signed-off-by: Jeff Layton <jlayton@...hat.com>
---
 fs/namei.c | 81 ++++++++++++++++++++++++++++++++++----------------------------
 1 file changed, 44 insertions(+), 37 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index b73315d..0d0b1c0 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3347,49 +3347,56 @@ static long do_rmdir(int dfd, const char __user *pathname)
 	struct getname_info *name;
 	struct dentry *dentry;
 	struct nameidata nd;
+	unsigned int try = 0;
+	unsigned int lookup_flags = LOOKUP_PARENT;
 
-	name = user_path_parent(dfd, pathname, &nd, 0);
-	if (IS_ERR(name))
-		return PTR_ERR(name);
-
-	switch(nd.last_type) {
-	case LAST_DOTDOT:
-		error = -ENOTEMPTY;
-		goto exit1;
-	case LAST_DOT:
-		error = -EINVAL;
-		goto exit1;
-	case LAST_ROOT:
-		error = -EBUSY;
-		goto exit1;
-	}
+	do {
+		name = user_path_parent(dfd, pathname, &nd, try);
+		if (IS_ERR(name))
+			return PTR_ERR(name);
+
+		switch (nd.last_type) {
+		case LAST_DOTDOT:
+			error = -ENOTEMPTY;
+			goto exit1;
+		case LAST_DOT:
+			error = -EINVAL;
+			goto exit1;
+		case LAST_ROOT:
+			error = -EBUSY;
+			goto exit1;
+		}
 
-	nd.flags &= ~LOOKUP_PARENT;
-	error = mnt_want_write(nd.path.mnt);
-	if (error)
-		goto exit1;
+		nd.flags &= ~LOOKUP_PARENT;
+		error = mnt_want_write(nd.path.mnt);
+		if (error)
+			goto exit1;
 
-	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
-	dentry = lookup_hash(&nd);
-	error = PTR_ERR(dentry);
-	if (IS_ERR(dentry))
-		goto exit2;
-	if (!dentry->d_inode) {
-		error = -ENOENT;
-		goto exit3;
-	}
-	error = security_path_rmdir(&nd.path, dentry);
-	if (error)
-		goto exit3;
-	error = vfs_rmdir(nd.path.dentry->d_inode, dentry);
+		mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex,
+					I_MUTEX_PARENT);
+		dentry = lookup_hash(&nd);
+		if (IS_ERR(dentry)) {
+			error = PTR_ERR(dentry);
+			goto exit2;
+		}
+		if (!dentry->d_inode) {
+			error = -ENOENT;
+			goto exit3;
+		}
+		error = security_path_rmdir(&nd.path, dentry);
+		if (error)
+			goto exit3;
+		error = vfs_rmdir(nd.path.dentry->d_inode, dentry);
 exit3:
-	dput(dentry);
+		dput(dentry);
 exit2:
-	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
-	mnt_drop_write(nd.path.mnt);
+		mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
+		mnt_drop_write(nd.path.mnt);
 exit1:
-	path_put(&nd.path);
-	putname(name);
+		path_put(&nd.path);
+		lookup_flags |= LOOKUP_REVAL;
+		putname(name);
+	} while (retry_estale(error, try++));
 	return error;
 }
 
-- 
1.7.11.4

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