Commit 412f84cf authored by Hans de Goede's avatar Hans de Goede Committed by Greg Kroah-Hartman
Browse files

virt: vbox: Add vbg_set_host_capabilities() helper function 



Add vbg_set_host_capabilities() helper function,  this is a preparation
patch for adding support for the VBGL_IOCTL_GUEST_CAPS_ACQUIRE ioctl.

Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200709120858.63928-5-hdegoede@redhat.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent fd01cc59

drivers/virt/vboxguest/vboxguest_core.c

+46 −33
Original line number Diff line number Diff line
@@ -661,6 +661,48 @@ static int vbg_reset_host_capabilities(struct vbg_dev *gdev) 
	return vbg_status_code_to_errno(rc);

}



/**

 * Set guest capabilities on the host.

 * Must be called with gdev->session_mutex hold.

 * Return: 0 or negative errno value.

 * @gdev:			The Guest extension device.

 * @session:			The session.

 * @session_termination:	Set if we're called by the session cleanup code.

 */

static int vbg_set_host_capabilities(struct vbg_dev *gdev,

				     struct vbg_session *session,

				     bool session_termination)

{

	struct vmmdev_mask *req;

	u32 caps;

	int rc;



	WARN_ON(!mutex_is_locked(&gdev->session_mutex));



	caps = gdev->set_guest_caps_tracker.mask;



	if (gdev->guest_caps_host == caps)

		return 0;



	/* On termination the requestor is the kernel, as we're cleaning up. */

	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_SET_GUEST_CAPABILITIES,

			    session_termination ? VBG_KERNEL_REQUEST :

						  session->requestor);

	if (!req) {

		gdev->guest_caps_host = U32_MAX;

		return -ENOMEM;

	}



	req->or_mask = caps;

	req->not_mask = ~caps;

	rc = vbg_req_perform(gdev, req);

	vbg_req_free(req, sizeof(*req));



	gdev->guest_caps_host = (rc >= 0) ? caps : U32_MAX;



	return vbg_status_code_to_errno(rc);

}



/**

 * Sets the guest capabilities for a session. Takes the session spinlock.

 * Return: 0 or negative errno value.
@@ -678,23 +720,8 @@ static int vbg_set_session_capabilities(struct vbg_dev *gdev, 
					u32 or_mask, u32 not_mask,

					bool session_termination)

{

	struct vmmdev_mask *req;

	u32 changed, previous;

	int rc, ret = 0;



	/*

	 * Allocate a request buffer before taking the spinlock, when

	 * the session is being terminated the requestor is the kernel,

	 * as we're cleaning up.

	 */

	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_SET_GUEST_CAPABILITIES,

			    session_termination ? VBG_KERNEL_REQUEST :

						  session->requestor);

	if (!req) {

		if (!session_termination)

			return -ENOMEM;

		/* Ignore allocation failure, we must do session cleanup. */

	}

	int ret = 0;



	mutex_lock(&gdev->session_mutex);
@@ -709,23 +736,10 @@ static int vbg_set_session_capabilities(struct vbg_dev *gdev, 
		goto out;



	vbg_track_bit_usage(&gdev->set_guest_caps_tracker, changed, previous);

	or_mask = gdev->set_guest_caps_tracker.mask;



	if (gdev->guest_caps_host == or_mask || !req)

		goto out;



	gdev->guest_caps_host = or_mask;

	req->or_mask = or_mask;

	req->not_mask = ~or_mask;

	rc = vbg_req_perform(gdev, req);

	if (rc < 0) {

		ret = vbg_status_code_to_errno(rc);



		/* Failed, roll back (unless it's session termination time). */

		gdev->guest_caps_host = U32_MAX;

		if (session_termination)

			goto out;



	ret = vbg_set_host_capabilities(gdev, session, session_termination);

	/* Roll back on failure, unless it's session termination time. */

	if (ret < 0 && !session_termination) {

		vbg_track_bit_usage(&gdev->set_guest_caps_tracker, changed,

				    session->set_guest_caps);

		session->set_guest_caps = previous;
@@ -733,7 +747,6 @@ static int vbg_set_session_capabilities(struct vbg_dev *gdev, 


out:

	mutex_unlock(&gdev->session_mutex);

	vbg_req_free(req, sizeof(*req));



	return ret;

}