X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=src%2Flttng-abi.c;h=6eb838752111ab207fe94dca18ece53fc85b0161;hb=21f58fb7e62071dae3ddf13817631749bcab4e00;hp=3bc2d1fb7c3df1a979ef1992f14554079dbddff3;hpb=a3fcd49911634cdfe26916b0f5983849debaea0b;p=lttng-modules.git

diff --git a/src/lttng-abi.c b/src/lttng-abi.c
index 3bc2d1fb..6eb83875 100644
--- a/src/lttng-abi.c
+++ b/src/lttng-abi.c
@@ -59,6 +59,7 @@ static const struct file_operations lttng_proc_ops;
 #endif
 
 static const struct file_operations lttng_session_fops;
+static const struct file_operations lttng_event_notifier_group_fops;
 static const struct file_operations lttng_channel_fops;
 static const struct file_operations lttng_metadata_fops;
 static const struct file_operations lttng_event_fops;
@@ -105,6 +106,52 @@ fd_error:
 	return ret;
 }
 
+void event_notifier_send_notification_work_wakeup(struct irq_work *entry)
+{
+	struct lttng_event_notifier_group *event_notifier_group =
+			container_of(entry, struct lttng_event_notifier_group,
+					wakeup_pending);
+	wake_up_interruptible(&event_notifier_group->read_wait);
+}
+
+static
+int lttng_abi_create_event_notifier_group(void)
+{
+	struct lttng_event_notifier_group *event_notifier_group;
+	struct file *event_notifier_group_file;
+	int event_notifier_group_fd, ret;
+
+	event_notifier_group = lttng_event_notifier_group_create();
+	if (!event_notifier_group)
+		return -ENOMEM;
+
+	event_notifier_group_fd = lttng_get_unused_fd();
+	if (event_notifier_group_fd < 0) {
+		ret = event_notifier_group_fd;
+		goto fd_error;
+	}
+	event_notifier_group_file = anon_inode_getfile("[lttng_event_notifier_group]",
+					  &lttng_event_notifier_group_fops,
+					  event_notifier_group, O_RDWR);
+	if (IS_ERR(event_notifier_group_file)) {
+		ret = PTR_ERR(event_notifier_group_file);
+		goto file_error;
+	}
+
+	event_notifier_group->file = event_notifier_group_file;
+	init_waitqueue_head(&event_notifier_group->read_wait);
+	init_irq_work(&event_notifier_group->wakeup_pending,
+		      event_notifier_send_notification_work_wakeup);
+	fd_install(event_notifier_group_fd, event_notifier_group_file);
+	return event_notifier_group_fd;
+
+file_error:
+	put_unused_fd(event_notifier_group_fd);
+fd_error:
+	lttng_event_notifier_group_destroy(event_notifier_group);
+	return ret;
+}
+
 static
 int lttng_abi_tracepoint_list(void)
 {
@@ -306,6 +353,8 @@ long lttng_abi_add_context(struct file *file,
  *		Returns after all previously running probes have completed
  *	LTTNG_KERNEL_TRACER_ABI_VERSION
  *		Returns the LTTng kernel tracer ABI version
+ *	LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_CREATE
+ *		Returns a LTTng event notifier group file descriptor
  *
  * The returned session will be deleted when its file descriptor is closed.
  */
@@ -316,6 +365,8 @@ long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	case LTTNG_KERNEL_OLD_SESSION:
 	case LTTNG_KERNEL_SESSION:
 		return lttng_abi_create_session();
+	case LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_CREATE:
+		return lttng_abi_create_event_notifier_group();
 	case LTTNG_KERNEL_OLD_TRACER_VERSION:
 	{
 		struct lttng_kernel_tracer_version v;
@@ -764,6 +815,10 @@ static const struct file_operations lttng_session_fops = {
 #endif
 };
 
+static const struct file_operations lttng_event_notifier_group_notif_fops = {
+	.owner = THIS_MODULE,
+};
+
 /**
  *	lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
  *	@filp: the file
@@ -1267,6 +1322,41 @@ nomem:
 	return ret;
 }
 
+static
+int lttng_abi_open_event_notifier_group_stream(struct file *notif_file)
+{
+	struct lttng_event_notifier_group *event_notifier_group = notif_file->private_data;
+	struct channel *chan = event_notifier_group->chan;
+	struct lib_ring_buffer *buf;
+	int ret;
+	void *stream_priv;
+
+	buf = event_notifier_group->ops->buffer_read_open(chan);
+	if (!buf)
+		return -ENOENT;
+
+	/* The event_notifier notification fd holds a reference on the event_notifier group */
+	if (!atomic_long_add_unless(&notif_file->f_count, 1, LONG_MAX)) {
+		ret = -EOVERFLOW;
+		goto refcount_error;
+	}
+	event_notifier_group->buf = buf;
+	stream_priv = event_notifier_group;
+	ret = lttng_abi_create_stream_fd(notif_file, stream_priv,
+			&lttng_event_notifier_group_notif_fops,
+			"[lttng_event_notifier_stream]");
+	if (ret < 0)
+		goto fd_error;
+
+	return ret;
+
+fd_error:
+	atomic_long_dec(&notif_file->f_count);
+refcount_error:
+	event_notifier_group->ops->buffer_read_close(buf);
+	return ret;
+}
+
 static
 int lttng_abi_validate_event_param(struct lttng_kernel_event *event_param)
 {
@@ -1398,6 +1488,233 @@ fd_error:
 	return ret;
 }
 
+static
+long lttng_event_notifier_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct lttng_event_notifier_enabler *event_notifier_enabler;
+	enum lttng_event_type *evtype = file->private_data;
+
+	switch (cmd) {
+	case LTTNG_KERNEL_ENABLE:
+		switch (*evtype) {
+		case LTTNG_TYPE_EVENT:
+			return -EINVAL;
+		case LTTNG_TYPE_ENABLER:
+			event_notifier_enabler = file->private_data;
+			return lttng_event_notifier_enabler_enable(event_notifier_enabler);
+		default:
+			WARN_ON_ONCE(1);
+			return -ENOSYS;
+		}
+	case LTTNG_KERNEL_DISABLE:
+		switch (*evtype) {
+		case LTTNG_TYPE_EVENT:
+			return -EINVAL;
+		case LTTNG_TYPE_ENABLER:
+			event_notifier_enabler = file->private_data;
+			return lttng_event_notifier_enabler_disable(event_notifier_enabler);
+		default:
+			WARN_ON_ONCE(1);
+			return -ENOSYS;
+		}
+	case LTTNG_KERNEL_FILTER:
+		switch (*evtype) {
+		case LTTNG_TYPE_EVENT:
+			return -EINVAL;
+		case LTTNG_TYPE_ENABLER:
+			event_notifier_enabler = file->private_data;
+			return lttng_event_notifier_enabler_attach_bytecode(event_notifier_enabler,
+				(struct lttng_kernel_filter_bytecode __user *) arg);
+		default:
+			WARN_ON_ONCE(1);
+			return -ENOSYS;
+		}
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+
+static
+int lttng_event_notifier_release(struct inode *inode, struct file *file)
+{
+	struct lttng_event_notifier *event_notifier;
+	struct lttng_event_notifier_enabler *event_notifier_enabler;
+	enum lttng_event_type *evtype = file->private_data;
+
+	if (!evtype)
+		return 0;
+
+	switch (*evtype) {
+	case LTTNG_TYPE_EVENT:
+		event_notifier = file->private_data;
+		if (event_notifier)
+			fput(event_notifier->group->file);
+		break;
+	case LTTNG_TYPE_ENABLER:
+		event_notifier_enabler = file->private_data;
+		if (event_notifier_enabler)
+			fput(event_notifier_enabler->group->file);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		break;
+	}
+
+	return 0;
+}
+
+static const struct file_operations lttng_event_notifier_fops = {
+	.owner = THIS_MODULE,
+	.release = lttng_event_notifier_release,
+	.unlocked_ioctl = lttng_event_notifier_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = lttng_event_notifier_ioctl,
+#endif
+};
+
+static
+int lttng_abi_create_event_notifier(struct file *event_notifier_group_file,
+		struct lttng_kernel_event_notifier *event_notifier_param)
+{
+	struct lttng_event_notifier_group *event_notifier_group =
+			event_notifier_group_file->private_data;
+	int event_notifier_fd, ret;
+	struct file *event_notifier_file;
+	void *priv;
+
+	switch (event_notifier_param->event.instrumentation) {
+	case LTTNG_KERNEL_TRACEPOINT:
+	case LTTNG_KERNEL_KPROBE:
+	case LTTNG_KERNEL_UPROBE:
+	case LTTNG_KERNEL_KRETPROBE:
+	case LTTNG_KERNEL_FUNCTION:
+	case LTTNG_KERNEL_NOOP:
+	case LTTNG_KERNEL_SYSCALL:
+	default:
+		ret = -EINVAL;
+		goto inval_instr;
+	}
+
+	event_notifier_param->event.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
+
+	event_notifier_fd = lttng_get_unused_fd();
+	if (event_notifier_fd < 0) {
+		ret = event_notifier_fd;
+		goto fd_error;
+	}
+
+	event_notifier_file = anon_inode_getfile("[lttng_event_notifier]",
+					&lttng_event_notifier_fops,
+					NULL, O_RDWR);
+	if (IS_ERR(event_notifier_file)) {
+		ret = PTR_ERR(event_notifier_file);
+		goto file_error;
+	}
+
+	/* The event notifier holds a reference on the event notifier group. */
+	if (!atomic_long_add_unless(&event_notifier_group_file->f_count, 1, LONG_MAX)) {
+		ret = -EOVERFLOW;
+		goto refcount_error;
+	}
+
+	if (event_notifier_param->event.instrumentation == LTTNG_KERNEL_TRACEPOINT
+			|| event_notifier_param->event.instrumentation == LTTNG_KERNEL_SYSCALL) {
+		struct lttng_event_notifier_enabler *enabler;
+
+		if (strutils_is_star_glob_pattern(event_notifier_param->event.name)) {
+			/*
+			 * If the event name is a star globbing pattern,
+			 * we create the special star globbing enabler.
+			 */
+			enabler = lttng_event_notifier_enabler_create(
+					event_notifier_group,
+					LTTNG_ENABLER_FORMAT_STAR_GLOB,
+					event_notifier_param);
+		} else {
+			enabler = lttng_event_notifier_enabler_create(
+					event_notifier_group,
+					LTTNG_ENABLER_FORMAT_NAME,
+					event_notifier_param);
+		}
+		priv = enabler;
+	} else {
+		struct lttng_event_notifier *event_notifier;
+
+		/*
+		 * We tolerate no failure path after event notifier creation.
+		 * It will stay invariant for the rest of the session.
+		 */
+		event_notifier = lttng_event_notifier_create(NULL,
+				event_notifier_param->event.token, event_notifier_group,
+				event_notifier_param, NULL,
+				event_notifier_param->event.instrumentation);
+		WARN_ON_ONCE(!event_notifier);
+		if (IS_ERR(event_notifier)) {
+			ret = PTR_ERR(event_notifier);
+			goto event_notifier_error;
+		}
+		priv = event_notifier;
+	}
+	event_notifier_file->private_data = priv;
+	fd_install(event_notifier_fd, event_notifier_file);
+	return event_notifier_fd;
+
+event_notifier_error:
+	atomic_long_dec(&event_notifier_group_file->f_count);
+refcount_error:
+	fput(event_notifier_file);
+file_error:
+	put_unused_fd(event_notifier_fd);
+fd_error:
+inval_instr:
+	return ret;
+}
+
+static
+long lttng_event_notifier_group_ioctl(struct file *file, unsigned int cmd,
+		unsigned long arg)
+{
+	switch (cmd) {
+	case LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_NOTIFICATION_FD:
+	{
+		return lttng_abi_open_event_notifier_group_stream(file);
+	}
+	case LTTNG_KERNEL_EVENT_NOTIFIER_CREATE:
+	{
+		struct lttng_kernel_event_notifier uevent_notifier_param;
+
+		if (copy_from_user(&uevent_notifier_param,
+				(struct lttng_kernel_event_notifier __user *) arg,
+				sizeof(uevent_notifier_param)))
+			return -EFAULT;
+		return lttng_abi_create_event_notifier(file, &uevent_notifier_param);
+	}
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+static
+int lttng_event_notifier_group_release(struct inode *inode, struct file *file)
+{
+	struct lttng_event_notifier_group *event_notifier_group =
+			file->private_data;
+
+	if (event_notifier_group)
+		lttng_event_notifier_group_destroy(event_notifier_group);
+	return 0;
+}
+
+static const struct file_operations lttng_event_notifier_group_fops = {
+	.owner = THIS_MODULE,
+	.release = lttng_event_notifier_group_release,
+	.unlocked_ioctl = lttng_event_notifier_group_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = lttng_event_notifier_group_ioctl,
+#endif
+};
+
 /**
  *	lttng_channel_ioctl - lttng syscall through ioctl
  *