[PATCH 2/2] [9p] Introduce client side TFSYNC/RFSYNC for dotl.

["Venkateswararao Jujjuri (JV)" <jvrao@linux.vnet.ibm.com>]

SYNOPSIS
    size[4] Tfsync tag[2] fid[4]

    size[4] Rfsync tag[2]

DESCRIPTION

The Tfsync transaction transfers ("flushes") all modified in-core data of
file identified by fid to the disk device (or other  permanent  storage
device)  where that  file  resides.

Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
---
 fs/9p/vfs_file.c        |   18 ++++++++++++++++--
 include/net/9p/9p.h     |    2 ++
 include/net/9p/client.h |    1 +
 net/9p/client.c         |   25 +++++++++++++++++++++++++
 4 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 28db7fb..fdf3032 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -290,6 +290,20 @@ static int v9fs_file_fsync(struct file *filp, int datasync)
 	return retval;
 }
 
+static int v9fs_file_fsync_dotl(struct file *filp, int datasync)
+{
+	struct p9_fid *fid;
+	int retval;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "v9fs_file_fsync_dotl: filp %p datasync %x\n",
+			filp, datasync);
+
+	fid = filp->private_data;
+
+	retval = p9_client_fsync(fid);
+	return retval;
+}
+
 static const struct file_operations v9fs_cached_file_operations = {
 	.llseek = generic_file_llseek,
 	.read = do_sync_read,
@@ -311,7 +325,7 @@ static const struct file_operations v9fs_cached_file_operations_dotl = {
 	.release = v9fs_dir_release,
 	.lock = v9fs_file_lock,
 	.mmap = generic_file_readonly_mmap,
-	.fsync = v9fs_file_fsync,
+	.fsync = v9fs_file_fsync_dotl,
 };
 
 const struct file_operations v9fs_file_operations = {
@@ -333,5 +347,5 @@ const struct file_operations v9fs_file_operations_dotl = {
 	.release = v9fs_dir_release,
 	.lock = v9fs_file_lock,
 	.mmap = generic_file_readonly_mmap,
-	.fsync = v9fs_file_fsync,
+	.fsync = v9fs_file_fsync_dotl,
 };
diff --git a/include/net/9p/9p.h b/include/net/9p/9p.h
index a4a1b04..55e9605 100644
--- a/include/net/9p/9p.h
+++ b/include/net/9p/9p.h
@@ -163,6 +163,8 @@ enum p9_msg_t {
 	P9_RXATTRCREATE,
 	P9_TREADDIR = 40,
 	P9_RREADDIR,
+	P9_TFSYNC = 50,
+	P9_RFSYNC,
 	P9_TLINK = 70,
 	P9_RLINK,
 	P9_TMKDIR = 72,
diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index d1aa2cf..fbb23b4 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -232,6 +232,7 @@ int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, gid_t gid,
 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
 		gid_t gid, struct p9_qid *qid);
 int p9_client_clunk(struct p9_fid *fid);
+int p9_client_fsync(struct p9_fid *fid);
 int p9_client_remove(struct p9_fid *fid);
 int p9_client_read(struct p9_fid *fid, char *data, char __user *udata,
 							u64 offset, u32 count);
diff --git a/net/9p/client.c b/net/9p/client.c
index 208efce..124241b 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -1211,6 +1211,31 @@ int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
 }
 EXPORT_SYMBOL(p9_client_link);
 
+int p9_client_fsync(struct p9_fid *fid)
+{
+	int err;
+	struct p9_client *clnt;
+	struct p9_req_t *req;
+
+	P9_DPRINTK(P9_DEBUG_9P, ">>> TFSYNC fid %d\n", fid->fid);
+	err = 0;
+	clnt = fid->clnt;
+
+	req = p9_client_rpc(clnt, P9_TFSYNC, "d", fid->fid);
+	if (IS_ERR(req)) {
+		err = PTR_ERR(req);
+		goto error;
+	}
+
+	P9_DPRINTK(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
+
+	p9_free_req(clnt, req);
+
+error:
+	return err;
+}
+EXPORT_SYMBOL(p9_client_fsync);
+
 int p9_client_clunk(struct p9_fid *fid)
 {
 	int err;
-- 
1.6.5.2