ocfs2: Add the 'set version' message to the ocfs2_control device. (d4b95eef) · Commits · e / devices / android_kernel_fairphone_FP5

fs/ocfs2/stack_user.c

+119 −12

Original line number	Diff line number	Diff line
		@@ -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>
		@@ -50,8 +50,22 @@
		* 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>
		*
		@@ -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 ocfs2_control_private {
		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 @@ struct ocfs2_control_message_setn {
		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 @@ struct ocfs2_control_message_down {
		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 @@ static void ocfs2_control_send_down(const char *uuid,
		/*
		* 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 @@ static int ocfs2_control_install_private(struct file *file)

		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 @@ static int ocfs2_control_do_setnode_msg(struct file *file,
		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 @@ static ssize_t ocfs2_control_message(struct file *file,
		!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 @@ static int ocfs2_control_release(struct inode inode, struct file file)
		"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: