[PATCH v2 12/17] locks: update Documentation/filesystems with new setlease semantics

Jeff Layton
2014-09-04T12:39:15Z

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
---
Documentation/filesystems/Locking | 11 ++++++-----
Documentation/filesystems/vfs.txt | 7 ++++---
2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index f1997e9da61f..94d93b1f8b53 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -464,15 +464,12 @@ prototypes:
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 **);
+ int (*setlease)(struct file *, long, struct file_lock **, void **);
long (*fallocate)(struct file *, int, loff_t, loff_t);
};

locking rules:
- All may block except for ->setlease.
- No VFS locks held on entry except for ->setlease.
-
-->setlease has the file_list_lock held and must not sleep.
+ All may block.

->llseek() locking has moved from llseek to the individual llseek
implementations. If your fs is not using generic_file_llseek, you
@@ -496,6 +493,10 @@ components. And there are other reasons why the current interface is a mess...
->read on directories probably must go away - we should just enforce -EISDIR
in sys_read() and friends.

+->setlease operations should call generic_setlease() before or after setting
+the lease within the individual filesystem to record the result of the
+operation
+
--------------------------- dquot_operations -------------------------------
prototypes:
int (*write_dquot) (struct dquot *);
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 61d65cc65c54..af9441f32a62 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -826,7 +826,7 @@ struct file_operations {
int (*flock) (struct file *, int, struct file_lock *);
ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, size_t, unsigned int);
ssize_t (*splice_read)(struct file *, struct pipe_inode_info *, size_t, unsigned int);
- int (*setlease)(struct file *, long arg, struct file_lock **);
+ int (*setlease)(struct file *, long arg, struct file_lock **, void **);
long (*fallocate)(struct file *, int mode, loff_t offset, loff_t len);
int (*show_fdinfo)(struct seq_file *m, struct file *f);
};
@@ -895,8 +895,9 @@ otherwise noted.
splice_read: called by the VFS to splice data from file to a pipe. This
method is used by the splice(2) system call

- setlease: called by the VFS to set or release a file lock lease.
- setlease has the file_lock_lock held and must not sleep.
+ setlease: called by the VFS to set or release a file lock lease. setlease
+ implementations should call generic_setlease to record or remove
+ the lease in the inode after setting it

fallocate: called by the VFS to preallocate blocks or punch a hole.

--
1.9.3