[PATCH 02/18] VFS: move delegated_inode retry loop into lookup_open()

From: NeilBrown <[email protected]>

By moving this retry into lookup_open() we no longer need to pass around
the delegated_inode pointer.

Various variable assignments need to be moved out of the declaration
block so that they can still happen after the goto.

Signed-off-by: NeilBrown <[email protected]>
---
 fs/namei.c | 42 +++++++++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 19 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 998fde251fcf..b00ff3f2faf7 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -4403,17 +4403,23 @@ static struct dentry *atomic_open(const struct path *path, struct dentry *dentry
  * An error code is returned on failure.
  */
 static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
-				  const struct open_flags *op,
-				  struct delegated_inode *delegated_inode)
+				  const struct open_flags *op)
 {
+	struct delegated_inode delegated_inode = { };
 	struct mnt_idmap *idmap;
 	struct dentry *dir = nd->path.dentry;
 	struct inode *dir_inode = dir->d_inode;
-	int open_flag = op->open_flag;
+	int open_flag;
 	struct dentry *dentry;
-	int error, create_error = 0;
-	umode_t mode = op->mode;
-	bool got_write = false;
+	int error, create_error;
+	umode_t mode;
+	bool got_write;
+
+retry:
+	open_flag = op->open_flag;
+	got_write = false;
+	mode = op->mode;
+	create_error = 0;
 
 	if (open_flag & (O_CREAT | O_TRUNC | O_WRONLY | O_RDWR)) {
 		got_write = !mnt_want_write(nd->path.mnt);
@@ -4511,7 +4517,7 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
 	/* Negative dentry, just create the file */
 	if (!dentry->d_inode && (open_flag & O_CREAT)) {
 		/* but break the directory lease first! */
-		error = try_break_deleg(dir_inode, LEASE_BREAK_DIR_CREATE, delegated_inode);
+		error = try_break_deleg(dir_inode, LEASE_BREAK_DIR_CREATE, &delegated_inode);
 		if (error)
 			goto out_dput;
 
@@ -4546,6 +4552,14 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
 	if (got_write)
 		mnt_drop_write(nd->path.mnt);
 
+	if (is_delegated(&delegated_inode)) {
+		/* Must have come through out_dput */
+		error = break_deleg_wait(&delegated_inode);
+
+		if (!error)
+			goto retry;
+	}
+
 	return dentry;
 
 out_dput:
@@ -4593,7 +4607,6 @@ static struct dentry *lookup_fast_for_open(struct nameidata *nd, int open_flag)
 static const char *open_last_lookups(struct nameidata *nd,
 		   struct file *file, const struct open_flags *op)
 {
-	struct delegated_inode delegated_inode = { };
 	int open_flag = op->open_flag;
 	struct dentry *dentry;
 	const char *res;
@@ -4623,19 +4636,10 @@ static const char *open_last_lookups(struct nameidata *nd,
 				return ERR_PTR(-ECHILD);
 		}
 	}
-retry:
-	dentry = lookup_open(nd, file, op, &delegated_inode);
-
-	if (IS_ERR(dentry)) {
-		if (is_delegated(&delegated_inode)) {
-			int error = break_deleg_wait(&delegated_inode);
 
-			if (!error)
-				goto retry;
-			return ERR_PTR(error);
-		}
+	dentry = lookup_open(nd, file, op);
+	if (IS_ERR(dentry))
 		return ERR_CAST(dentry);
-	}
 
 	if (file->f_mode & (FMODE_OPENED | FMODE_CREATED)) {
 		dput(nd->path.dentry);
-- 
2.50.0.107.gf914562f5916.dirty