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

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>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

4 files changed, 44 insertions, 2 deletions

diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 28db7fb1d96..fdf303207c7 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 a4a1b043a8c..55e96057f47 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 7f63d5ab7b4..8744e3ad4a0 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -229,6 +229,7 @@ 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 e50ec802937..30c4a1b224f 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -1162,6 +1162,31 @@ 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;