net/9p: This patch implements TLERROR/RLERROR on the 9P client.

Signed-off-by: NArun R Bharadwaj <arun@linux.vnet.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

include/net/9p/9p.h

@@ -86,6 +86,8 @@ do { \
 
 /**
  * enum p9_msg_t - 9P message types
+ * @P9_TLERROR: not used
+ * @P9_RLERROR: response for any failed request for 9P2000.L
  * @P9_TSTATFS: file system status request
  * @P9_RSTATFS: file system status response
  * @P9_TSYMLINK: make symlink request
@@ -137,6 +139,8 @@ do { \
  */
 
 enum p9_msg_t {
+	P9_TLERROR = 6,
+	P9_RLERROR,
 	P9_TSTATFS = 8,
 	P9_RSTATFS,
 	P9_TLOPEN = 12,

net/9p/client.c

@@ -450,32 +450,43 @@ static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 		return err;
 	}
 
-	if (type == P9_RERROR) {
+	if (type == P9_RERROR || type == P9_RLERROR) {
 		int ecode;
-		char *ename;
 
-		err = p9pdu_readf(req->rc, c->proto_version, "s?d",
-							&ename, &ecode);
-		if (err) {
-			P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
-									err);
-			return err;
-		}
+		if (!p9_is_proto_dotl(c)) {
+			char *ename;
 
-		if (p9_is_proto_dotu(c) ||
-			p9_is_proto_dotl(c))
-			err = -ecode;
+			err = p9pdu_readf(req->rc, c->proto_version, "s?d",
+								&ename, &ecode);
+			if (err)
+				goto out_err;
 
-		if (!err || !IS_ERR_VALUE(err))
-			err = p9_errstr2errno(ename, strlen(ename));
+			if (p9_is_proto_dotu(c))
+				err = -ecode;
 
-		P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
+			if (!err || !IS_ERR_VALUE(err)) {
+				err = p9_errstr2errno(ename, strlen(ename));
+
+				P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
+
+				kfree(ename);
+			}
+		} else {
+			err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
+			err = -ecode;
+
+			P9_DPRINTK(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
+		}
 
-		kfree(ename);
 	} else
 		err = 0;
 
 	return err;
+
+out_err:
+	P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
+
+	return err;
 }
 
 /**