From 5dbb7975033ac39e17d833bc17a58a85633eccf5 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@fieldses.org>
Date: Tue, 14 Nov 2006 15:51:40 -0500
Subject: [PATCH] --- yaml --- r: 61448 b: refs/heads/master c:
 f9ffed26d6f3e6ac9988947242821579d615fda7 h: refs/heads/master v: v3

---
 [refs]                   |  2 +-
 trunk/fs/locks.c         | 24 ++++++++++++++++++++++--
 trunk/include/linux/fs.h |  1 +
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 43afbedbdcc7..bb1467bdb23c 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a9933cea7a1d80dd9efae9f1acd857f5dce742b9
+refs/heads/master: f9ffed26d6f3e6ac9988947242821579d615fda7
diff --git a/trunk/fs/locks.c b/trunk/fs/locks.c
index a65d85c1fdc2..94f5d8065e3a 100644
--- a/trunk/fs/locks.c
+++ b/trunk/fs/locks.c
@@ -1429,7 +1429,24 @@ static int setlease(struct file *filp, long arg, struct file_lock **flp)
  *	@lease: file_lock to use
  *
  *	Call this to establish a lease on the file.
- *	The fl_lmops fl_break function is required by break_lease
+ *	The (*lease)->fl_lmops->fl_break operation must be set; if not,
+ *	break_lease will oops!
+ *
+ *	This will call the filesystem's setlease file method, if
+ *	defined.  Note that there is no getlease method; instead, the
+ *	filesystem setlease method should call back to setlease() to
+ *	add a lease to the inode's lease list, where fcntl_getlease() can
+ *	find it.  Since fcntl_getlease() only reports whether the current
+ *	task holds a lease, a cluster filesystem need only do this for
+ *	leases held by processes on this node.
+ *
+ *	There is also no break_lease method; filesystems that
+ *	handle their own leases shoud break leases themselves from the
+ *	filesystem's open, create, and (on truncate) setattr methods.
+ *
+ *	Warning: the only current setlease methods exist only to disable
+ *	leases in certain cases.  More vfs changes may be required to
+ *	allow a full filesystem lease implementation.
  */
 
 int vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
@@ -1437,7 +1454,10 @@ int vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
 	int error;
 
 	lock_kernel();
-	error = setlease(filp, arg, lease);
+	if (filp->f_op && filp->f_op->setlease)
+		error = filp->f_op->setlease(filp, arg, lease);
+	else
+		error = setlease(filp, arg, lease);
 	unlock_kernel();
 
 	return error;
diff --git a/trunk/include/linux/fs.h b/trunk/include/linux/fs.h
index a24f029accc0..c8ddf34e9710 100644
--- a/trunk/include/linux/fs.h
+++ b/trunk/include/linux/fs.h
@@ -1122,6 +1122,7 @@ struct file_operations {
 	int (*flock) (struct file *, int, struct file_lock *);
 	ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
 	ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
+	int (*setlease)(struct file *, long, struct file_lock **);
 };
 
 struct inode_operations {