[PATCH] v9fs: Support to force umount

Support for force umount
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/9p/mux.c

@@ -323,6 +323,26 @@ v9fs_mux_rpc(struct v9fs_session_info *v9ses, struct v9fs_fcall *tcall,
 	return ret;
 }
 
+/**
+ * v9fs_mux_cancel_requests - cancels all pending requests
+ *
+ * @v9ses: session info structure
+ * @err: error code to return to the requests
+ */
+void v9fs_mux_cancel_requests(struct v9fs_session_info *v9ses, int err)
+{
+	struct v9fs_rpcreq *rptr;
+	struct v9fs_rpcreq *rreq;
+
+	dprintk(DEBUG_MUX, " %d\n", err);
+	spin_lock(&v9ses->muxlock);
+	list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) {
+		rreq->err = err;
+	}
+	spin_unlock(&v9ses->muxlock);
+	wake_up_all(&v9ses->read_wait);
+}
+
 /**
  * v9fs_recvproc - kproc to handle demultiplexing responses
  * @data: session info structure

fs/9p/mux.h

@@ -37,3 +37,4 @@ struct v9fs_rpcreq {
 int v9fs_mux_init(struct v9fs_session_info *v9ses, const char *dev_name);
 long v9fs_mux_rpc(struct v9fs_session_info *v9ses,
 		  struct v9fs_fcall *tcall, struct v9fs_fcall **rcall);
+void v9fs_mux_cancel_requests(struct v9fs_session_info *v9ses, int err);

fs/9p/v9fs.c

@@ -409,6 +409,15 @@ void v9fs_session_close(struct v9fs_session_info *v9ses)
 	putname(v9ses->remotename);
 }
 
+/**
+ * v9fs_session_cancel - mark transport as disconnected
+ * 	and cancel all pending requests.
+ */
+void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
+	v9ses->transport->status = Disconnected;
+	v9fs_mux_cancel_requests(v9ses, -EIO);
+}
+
 extern int v9fs_error_init(void);
 
 /**

fs/9p/v9fs.h

@@ -89,9 +89,7 @@ struct v9fs_session_info *v9fs_inode2v9ses(struct inode *);
 void v9fs_session_close(struct v9fs_session_info *v9ses);
 int v9fs_get_idpool(struct v9fs_idpool *p);
 void v9fs_put_idpool(int id, struct v9fs_idpool *p);
-int v9fs_get_option(char *opts, char *name, char *buf, int buflen);
-long long v9fs_get_int_option(char *opts, char *name, long long dflt);
-int v9fs_parse_tcp_devname(const char *devname, char **addr, char **remotename);
+void v9fs_session_cancel(struct v9fs_session_info *v9ses);
 
 #define V9FS_MAGIC 0x01021997
 

fs/9p/vfs_super.c

@@ -257,10 +257,19 @@ static int v9fs_show_options(struct seq_file *m, struct vfsmount *mnt)
 	return 0;
 }
 
+static void
+v9fs_umount_begin(struct super_block *sb)
+{
+	struct v9fs_session_info *v9ses = sb->s_fs_info;
+
+	v9fs_session_cancel(v9ses);
+}
+
 static struct super_operations v9fs_super_ops = {
 	.statfs = simple_statfs,
 	.clear_inode = v9fs_clear_inode,
 	.show_options = v9fs_show_options,
+	.umount_begin = v9fs_umount_begin,
 };
 
 struct file_system_type v9fs_fs_type = {