[PATCH 09/27] afs: Flush outstanding writes when an fd is closed

From: David Howells
Date: Thu Mar 09 2017 - 13:57:07 EST


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

Reported-by: Marc Dionne <marc.c.dionne@xxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

fs/afs/file.c | 1 +
fs/afs/internal.h | 1 +
fs/afs/write.c | 14 ++++++++++++++
3 files changed, 16 insertions(+)

diff --git a/fs/afs/file.c b/fs/afs/file.c
index a38e1c30d110..b5829443ff69 100644
--- a/fs/afs/file.c
+++ b/fs/afs/file.c
@@ -30,6 +30,7 @@ static int afs_readpages(struct file *filp, struct address_space *mapping,

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,
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index dc2cb486e127..af1d91ec7f2c 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -720,6 +720,7 @@ extern int afs_writepages(struct address_space *, struct writeback_control *);
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);


diff --git a/fs/afs/write.c b/fs/afs/write.c
index ea66890fc188..f1450ea09406 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -758,6 +758,20 @@ int afs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
}

/*
+ * 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
*/