ocfs2: Add the 'set version' message to the ocfs2_control device.

The "SETV" message sets the filesystem locking protocol version as negotiated by the client. The client negotiates based on the maximum version advertised in /sys/fs/ocfs2/max_locking_protocol. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>

ocfs2: Add the 'set version' message to the ocfs2_control device.
The "SETV" message sets the filesystem locking protocol version as negotiated by the client. The client negotiates based on the maximum version advertised in /sys/fs/ocfs2/max_locking_protocol. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Joel Becker · Mark Fasheh
1 parent 3cfd4ab6b6
Showing 1 changed file with 119 additions and 12 deletions Side-by-side Diff
fs/ocfs2/stack_user.c
@@ -40,7 +40,7 @@
  * unknown, -EINVAL is returned.  Once the negotiation is complete, the
  * client can start sending messages.
  *
- * The T01 protocol only has two messages.  First is the "SETN" message.
+ * The T01 protocol has three messages.  First is the "SETN" message.
  * It has the following syntax:
  *
  *  SETN<space><8-char-hex-nodenum><newline>
  
@@ -50,9 +50,23 @@
  * The "SETN" message must be the first message following the protocol.
  * It tells ocfs2_control the local node number.
  *
- * Once the local node number has been set, the "DOWN" message can be
- * sent for node down notification.  It has the following syntax:
+ * Next comes the "SETV" message.  It has the following syntax:
  *
+ *  SETV<space><2-char-hex-major><space><2-char-hex-minor><newline>
+ *
+ * This is 11 characters.
+ *
+ * The "SETV" message sets the filesystem locking protocol version as
+ * negotiated by the client.  The client negotiates based on the maximum
+ * version advertised in /sys/fs/ocfs2/max_locking_protocol.  The major
+ * number from the "SETV" message must match
+ * user_stack.sp_proto->lp_max_version.pv_major, and the minor number
+ * must be less than or equal to ...->lp_max_version.pv_minor.
+ *
+ * Once this information has been set, mounts will be allowed.  From this
+ * point on, the "DOWN" message can be sent for node down notification.
+ * It has the following syntax:
+ *
  *  DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline>
  *
  * eg:
  
@@ -79,9 +93,12 @@
 #define OCFS2_CONTROL_MESSAGE_OP_LEN		4
 #define OCFS2_CONTROL_MESSAGE_SETNODE_OP	"SETN"
 #define OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN	14
+#define OCFS2_CONTROL_MESSAGE_SETVERSION_OP	"SETV"
+#define OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN	11
 #define OCFS2_CONTROL_MESSAGE_DOWN_OP		"DOWN"
 #define OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN	47
 #define OCFS2_TEXT_UUID_LEN			32
+#define OCFS2_CONTROL_MESSAGE_VERNUM_LEN	2
 #define OCFS2_CONTROL_MESSAGE_NODENUM_LEN	8
  
 /*
@@ -97,6 +114,7 @@
 	struct list_head op_list;
 	int op_state;
 	int op_this_node;
+	struct ocfs2_protocol_version op_proto;
 };
  
 /* SETN<space><8-char-hex-nodenum><newline> */
@@ -107,6 +125,16 @@
 	char	newline;
 };
  
+/* SETV<space><2-char-hex-major><space><2-char-hex-minor><newline> */
+struct ocfs2_control_message_setv {
+	char	tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
+	char	space1;
+	char	major[OCFS2_CONTROL_MESSAGE_VERNUM_LEN];
+	char	space2;
+	char	minor[OCFS2_CONTROL_MESSAGE_VERNUM_LEN];
+	char	newline;
+};
+
 /* DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline> */
 struct ocfs2_control_message_down {
 	char	tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
  
@@ -120,11 +148,13 @@
 union ocfs2_control_message {
 	char					tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
 	struct ocfs2_control_message_setn	u_setn;
+	struct ocfs2_control_message_setv	u_setv;
 	struct ocfs2_control_message_down	u_down;
 };
  
 static atomic_t ocfs2_control_opened;
 static int ocfs2_control_this_node = -1;
+static struct ocfs2_protocol_version running_proto;
  
 static LIST_HEAD(ocfs2_live_connection_list);
 static LIST_HEAD(ocfs2_control_private_list);
@@ -264,8 +294,9 @@
 /*
  * Called whenever configuration elements are sent to /dev/ocfs2_control.
  * If all configuration elements are present, try to set the global
- * values.  If not, return -EAGAIN.  If there is a problem, return a
- * different error.
+ * values.  If there is a problem, return an error.  Skip any missing
+ * elements, and only bump ocfs2_control_opened when we have all elements
+ * and are successful.
  */
 static int ocfs2_control_install_private(struct file *file)
 {
  
  
  
@@ -275,15 +306,32 @@
  
 	BUG_ON(p->op_state != OCFS2_CONTROL_HANDSHAKE_PROTOCOL);
  
-	if (p->op_this_node < 0)
+	mutex_lock(&ocfs2_control_lock);
+
+	if (p->op_this_node < 0) {
 		set_p = 0;
+	} else if ((ocfs2_control_this_node >= 0) &&
+		   (ocfs2_control_this_node != p->op_this_node)) {
+		rc = -EINVAL;
+		goto out_unlock;
+	}
  
-	mutex_lock(&ocfs2_control_lock);
-	if (ocfs2_control_this_node < 0) {
-		if (set_p)
-			ocfs2_control_this_node = p->op_this_node;
-	} else if (ocfs2_control_this_node != p->op_this_node)
+	if (!p->op_proto.pv_major) {
+		set_p = 0;
+	} else if (!list_empty(&ocfs2_live_connection_list) &&
+		   ((running_proto.pv_major != p->op_proto.pv_major) ||
+		    (running_proto.pv_minor != p->op_proto.pv_minor))) {
 		rc = -EINVAL;
+		goto out_unlock;
+	}
+
+	if (set_p) {
+		ocfs2_control_this_node = p->op_this_node;
+		running_proto.pv_major = p->op_proto.pv_major;
+		running_proto.pv_minor = p->op_proto.pv_minor;
+	}
+
+out_unlock:
 	mutex_unlock(&ocfs2_control_lock);
  
 	if (!rc && set_p) {
@@ -327,6 +375,56 @@
 	return ocfs2_control_install_private(file);
 }
  
+static int ocfs2_control_do_setversion_msg(struct file *file,
+					   struct ocfs2_control_message_setv *msg)
+ {
+	long major, minor;
+	char *ptr = NULL;
+	struct ocfs2_control_private *p = file->private_data;
+	struct ocfs2_protocol_version *max =
+		&user_stack.sp_proto->lp_max_version;
+
+	if (ocfs2_control_get_handshake_state(file) !=
+	    OCFS2_CONTROL_HANDSHAKE_PROTOCOL)
+		return -EINVAL;
+
+	if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP,
+		    OCFS2_CONTROL_MESSAGE_OP_LEN))
+		return -EINVAL;
+
+	if ((msg->space1 != ' ') || (msg->space2 != ' ') ||
+	    (msg->newline != '\n'))
+		return -EINVAL;
+	msg->space1 = msg->space2 = msg->newline = '\0';
+
+	major = simple_strtol(msg->major, &ptr, 16);
+	if (!ptr || *ptr)
+		return -EINVAL;
+	minor = simple_strtol(msg->minor, &ptr, 16);
+	if (!ptr || *ptr)
+		return -EINVAL;
+
+	/*
+	 * The major must be between 1 and 255, inclusive.  The minor
+	 * must be between 0 and 255, inclusive.  The version passed in
+	 * must be within the maximum version supported by the filesystem.
+	 */
+	if ((major == LONG_MIN) || (major == LONG_MAX) ||
+	    (major > (u8)-1) || (major < 1))
+		return -ERANGE;
+	if ((minor == LONG_MIN) || (minor == LONG_MAX) ||
+	    (minor > (u8)-1) || (minor < 0))
+		return -ERANGE;
+	if ((major != max->pv_major) ||
+	    (minor > max->pv_minor))
+		return -EINVAL;
+
+	p->op_proto.pv_major = major;
+	p->op_proto.pv_minor = minor;
+
+	return ocfs2_control_install_private(file);
+}
+
 static int ocfs2_control_do_down_msg(struct file *file,
 				     struct ocfs2_control_message_down *msg)
 {
@@ -379,6 +477,10 @@
 	    !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP,
 		     OCFS2_CONTROL_MESSAGE_OP_LEN))
 		ret = ocfs2_control_do_setnode_msg(file, &msg.u_setn);
+	else if ((count == OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN) &&
+		 !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP,
+			  OCFS2_CONTROL_MESSAGE_OP_LEN))
+		ret = ocfs2_control_do_setversion_msg(file, &msg.u_setv);
 	else if ((count == OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN) &&
 		 !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_DOWN_OP,
 			  OCFS2_CONTROL_MESSAGE_OP_LEN))
  
@@ -471,8 +573,13 @@
 			       "an emergency restart!\n");
 			emergency_restart();
 		}
-		/* Last valid close clears the node number */
+		/*
+		 * Last valid close clears the node number and resets
+		 * the locking protocol version
+		 */
 		ocfs2_control_this_node = -1;
+		running_proto.pv_major = 0;
+		running_proto.pv_major = 0;
 	}
  
 out:
...	...	@@ -40,7 +40,7 @@
40	40	* unknown, -EINVAL is returned. Once the negotiation is complete, the
41	41	* client can start sending messages.
42	42	*
43		- * The T01 protocol only has two messages. First is the "SETN" message.
	43	+ * The T01 protocol has three messages. First is the "SETN" message.
44	44	* It has the following syntax:
45	45	*
46	46	* SETN<space><8-char-hex-nodenum><newline>
47	47
...	...	@@ -50,9 +50,23 @@
50	50	* The "SETN" message must be the first message following the protocol.
51	51	* It tells ocfs2_control the local node number.
52	52	*
53		- * Once the local node number has been set, the "DOWN" message can be
54		- * sent for node down notification. It has the following syntax:
	53	+ * Next comes the "SETV" message. It has the following syntax:
55	54	*
	55	+ * SETV<space><2-char-hex-major><space><2-char-hex-minor><newline>
	56	+ *
	57	+ * This is 11 characters.
	58	+ *
	59	+ * The "SETV" message sets the filesystem locking protocol version as
	60	+ * negotiated by the client. The client negotiates based on the maximum
	61	+ * version advertised in /sys/fs/ocfs2/max_locking_protocol. The major
	62	+ * number from the "SETV" message must match
	63	+ * user_stack.sp_proto->lp_max_version.pv_major, and the minor number
	64	+ * must be less than or equal to ...->lp_max_version.pv_minor.
	65	+ *
	66	+ * Once this information has been set, mounts will be allowed. From this
	67	+ * point on, the "DOWN" message can be sent for node down notification.
	68	+ * It has the following syntax:
	69	+ *
56	70	* DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline>
57	71	*
58	72	* eg:
59	73
...	...	@@ -79,9 +93,12 @@
79	93	#define OCFS2_CONTROL_MESSAGE_OP_LEN 4
80	94	#define OCFS2_CONTROL_MESSAGE_SETNODE_OP "SETN"
81	95	#define OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN 14
	96	+#define OCFS2_CONTROL_MESSAGE_SETVERSION_OP "SETV"
	97	+#define OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN 11
82	98	#define OCFS2_CONTROL_MESSAGE_DOWN_OP "DOWN"
83	99	#define OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN 47
84	100	#define OCFS2_TEXT_UUID_LEN 32
	101	+#define OCFS2_CONTROL_MESSAGE_VERNUM_LEN 2
85	102	#define OCFS2_CONTROL_MESSAGE_NODENUM_LEN 8
86	103
87	104	/*
...	...	@@ -97,6 +114,7 @@
97	114	struct list_head op_list;
98	115	int op_state;
99	116	int op_this_node;
	117	+ struct ocfs2_protocol_version op_proto;
100	118	};
101	119
102	120	/* SETN<space><8-char-hex-nodenum><newline> */
...	...	@@ -107,6 +125,16 @@
107	125	char newline;
108	126	};
109	127
	128	+/* SETV<space><2-char-hex-major><space><2-char-hex-minor><newline> */
	129	+struct ocfs2_control_message_setv {
	130	+ char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
	131	+ char space1;
	132	+ char major[OCFS2_CONTROL_MESSAGE_VERNUM_LEN];
	133	+ char space2;
	134	+ char minor[OCFS2_CONTROL_MESSAGE_VERNUM_LEN];
	135	+ char newline;
	136	+};
	137	+
110	138	/* DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline> */
111	139	struct ocfs2_control_message_down {
112	140	char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
113	141
...	...	@@ -120,11 +148,13 @@
120	148	union ocfs2_control_message {
121	149	char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
122	150	struct ocfs2_control_message_setn u_setn;
	151	+ struct ocfs2_control_message_setv u_setv;
123	152	struct ocfs2_control_message_down u_down;
124	153	};
125	154
126	155	static atomic_t ocfs2_control_opened;
127	156	static int ocfs2_control_this_node = -1;
	157	+static struct ocfs2_protocol_version running_proto;
128	158
129	159	static LIST_HEAD(ocfs2_live_connection_list);
130	160	static LIST_HEAD(ocfs2_control_private_list);
...	...	@@ -264,8 +294,9 @@
264	294	/*
265	295	* Called whenever configuration elements are sent to /dev/ocfs2_control.
266	296	* If all configuration elements are present, try to set the global
267		- * values. If not, return -EAGAIN. If there is a problem, return a
268		- * different error.
	297	+ * values. If there is a problem, return an error. Skip any missing
	298	+ * elements, and only bump ocfs2_control_opened when we have all elements
	299	+ * and are successful.
269	300	*/
270	301	static int ocfs2_control_install_private(struct file *file)
271	302	{
272	303
273	304
274	305
...	...	@@ -275,15 +306,32 @@
275	306
276	307	BUG_ON(p->op_state != OCFS2_CONTROL_HANDSHAKE_PROTOCOL);
277	308
278		- if (p->op_this_node < 0)
	309	+ mutex_lock(&ocfs2_control_lock);
	310	+
	311	+ if (p->op_this_node < 0) {
279	312	set_p = 0;
	313	+ } else if ((ocfs2_control_this_node >= 0) &&
	314	+ (ocfs2_control_this_node != p->op_this_node)) {
	315	+ rc = -EINVAL;
	316	+ goto out_unlock;
	317	+ }
280	318
281		- mutex_lock(&ocfs2_control_lock);
282		- if (ocfs2_control_this_node < 0) {
283		- if (set_p)
284		- ocfs2_control_this_node = p->op_this_node;
285		- } else if (ocfs2_control_this_node != p->op_this_node)
	319	+ if (!p->op_proto.pv_major) {
	320	+ set_p = 0;
	321	+ } else if (!list_empty(&ocfs2_live_connection_list) &&
	322	+ ((running_proto.pv_major != p->op_proto.pv_major) \|\|
	323	+ (running_proto.pv_minor != p->op_proto.pv_minor))) {
286	324	rc = -EINVAL;
	325	+ goto out_unlock;
	326	+ }
	327	+
	328	+ if (set_p) {
	329	+ ocfs2_control_this_node = p->op_this_node;
	330	+ running_proto.pv_major = p->op_proto.pv_major;
	331	+ running_proto.pv_minor = p->op_proto.pv_minor;
	332	+ }
	333	+
	334	+out_unlock:
287	335	mutex_unlock(&ocfs2_control_lock);
288	336
289	337	if (!rc && set_p) {
...	...	@@ -327,6 +375,56 @@
327	375	return ocfs2_control_install_private(file);
328	376	}
329	377
	378	+static int ocfs2_control_do_setversion_msg(struct file *file,
	379	+ struct ocfs2_control_message_setv *msg)
	380	+ {
	381	+ long major, minor;
	382	+ char *ptr = NULL;
	383	+ struct ocfs2_control_private *p = file->private_data;
	384	+ struct ocfs2_protocol_version *max =
	385	+ &user_stack.sp_proto->lp_max_version;
	386	+
	387	+ if (ocfs2_control_get_handshake_state(file) !=
	388	+ OCFS2_CONTROL_HANDSHAKE_PROTOCOL)
	389	+ return -EINVAL;
	390	+
	391	+ if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP,
	392	+ OCFS2_CONTROL_MESSAGE_OP_LEN))
	393	+ return -EINVAL;
	394	+
	395	+ if ((msg->space1 != ' ') \|\| (msg->space2 != ' ') \|\|
	396	+ (msg->newline != '\n'))
	397	+ return -EINVAL;
	398	+ msg->space1 = msg->space2 = msg->newline = '\0';
	399	+
	400	+ major = simple_strtol(msg->major, &ptr, 16);
	401	+ if (!ptr \|\| *ptr)
	402	+ return -EINVAL;
	403	+ minor = simple_strtol(msg->minor, &ptr, 16);
	404	+ if (!ptr \|\| *ptr)
	405	+ return -EINVAL;
	406	+
	407	+ /*
	408	+ * The major must be between 1 and 255, inclusive. The minor
	409	+ * must be between 0 and 255, inclusive. The version passed in
	410	+ * must be within the maximum version supported by the filesystem.
	411	+ */
	412	+ if ((major == LONG_MIN) \|\| (major == LONG_MAX) \|\|
	413	+ (major > (u8)-1) \|\| (major < 1))
	414	+ return -ERANGE;
	415	+ if ((minor == LONG_MIN) \|\| (minor == LONG_MAX) \|\|
	416	+ (minor > (u8)-1) \|\| (minor < 0))
	417	+ return -ERANGE;
	418	+ if ((major != max->pv_major) \|\|
	419	+ (minor > max->pv_minor))
	420	+ return -EINVAL;
	421	+
	422	+ p->op_proto.pv_major = major;
	423	+ p->op_proto.pv_minor = minor;
	424	+
	425	+ return ocfs2_control_install_private(file);
	426	+}
	427	+
330	428	static int ocfs2_control_do_down_msg(struct file *file,
331	429	struct ocfs2_control_message_down *msg)
332	430	{
...	...	@@ -379,6 +477,10 @@
379	477	!strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP,
380	478	OCFS2_CONTROL_MESSAGE_OP_LEN))
381	479	ret = ocfs2_control_do_setnode_msg(file, &msg.u_setn);
	480	+ else if ((count == OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN) &&
	481	+ !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP,
	482	+ OCFS2_CONTROL_MESSAGE_OP_LEN))
	483	+ ret = ocfs2_control_do_setversion_msg(file, &msg.u_setv);
382	484	else if ((count == OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN) &&
383	485	!strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_DOWN_OP,
384	486	OCFS2_CONTROL_MESSAGE_OP_LEN))
385	487
...	...	@@ -471,8 +573,13 @@
471	573	"an emergency restart!\n");
472	574	emergency_restart();
473	575	}
474		- /* Last valid close clears the node number */
	576	+ /*
	577	+ * Last valid close clears the node number and resets
	578	+ * the locking protocol version
	579	+ */
475	580	ocfs2_control_this_node = -1;
	581	+ running_proto.pv_major = 0;
	582	+ running_proto.pv_major = 0;
476	583	}
477	584
478	585	out: