[PATCH 4.4 052/115] afs: Flush outstanding writes when an fd is closed

Greg Kroah-Hartman
2017-12-18T15:56:16Z

From: David Howells <dhowells@redhat.com>

[ Upstream commit 58fed94dfb17e89556b5705f20f90e5b2971b6a1 ]

Flush outstanding writes in afs when an fd is closed. This is what NFS and
CIFS do.

Reported-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/afs/file.c | 1 +
fs/afs/internal.h | 1 +
fs/afs/write.c | 14 ++++++++++++++
3 files changed, 16 insertions(+)

--- a/fs/afs/file.c
+++ b/fs/afs/file.c
@@ -29,6 +29,7 @@ static int afs_readpages(struct file *fi

const struct file_operations afs_file_operations = {
.open = afs_open,
+ .flush = afs_flush,
.release = afs_release,
.llseek = generic_file_llseek,
.read_iter = generic_file_read_iter,
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -749,6 +749,7 @@ extern int afs_writepages(struct address
extern void afs_pages_written_back(struct afs_vnode *, struct afs_call *);
extern ssize_t afs_file_write(struct kiocb *, struct iov_iter *);
extern int afs_writeback_all(struct afs_vnode *);
+extern int afs_flush(struct file *, fl_owner_t);
extern int afs_fsync(struct file *, loff_t, loff_t, int);

--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -741,6 +741,20 @@ out:
}

/*
+ * Flush out all outstanding writes on a file opened for writing when it is
+ * closed.
+ */
+int afs_flush(struct file *file, fl_owner_t id)
+{
+ _enter("");
+
+ if ((file->f_mode & FMODE_WRITE) == 0)
+ return 0;
+
+ return vfs_fsync(file, 0);
+}
+
+/*
* notification that a previously read-only page is about to become writable
* - if it returns an error, the caller will deliver a bus error signal
*/