1 files changed, 268 insertions, 0 deletions
diff --git a/drivers/usb/usbip/vhci_rx.c b/drivers/usb/usbip/vhci_rx.c
new file mode 100644
index 0000000..00e4a54
--- /dev/null
+++ b/drivers/usb/usbip/vhci_rx.c
@@ -0,0 +1,268 @@
+/*
+ * Copyright (C) 2003-2008 Takahiro Hirofuchi
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+ * USA.
+ */
+
+#include <linux/kthread.h>
+#include <linux/slab.h>
+
+#include "usbip_common.h"
+#include "vhci.h"
+
+/* get URB from transmitted urb queue. caller must hold vdev->priv_lock */
+struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev, __u32 seqnum)
+{
+	struct vhci_priv *priv, *tmp;
+	struct urb *urb = NULL;
+	int status;
+
+	list_for_each_entry_safe(priv, tmp, &vdev->priv_rx, list) {
+		if (priv->seqnum != seqnum)
+			continue;
+
+		urb = priv->urb;
+		status = urb->status;
+
+		usbip_dbg_vhci_rx("find urb %p vurb %p seqnum %u\n",
+				urb, priv, seqnum);
+
+		switch (status) {
+		case -ENOENT:
+			/* fall through */
+		case -ECONNRESET:
+			dev_info(&urb->dev->dev,
+				 "urb %p was unlinked %ssynchronuously.\n", urb,
+				 status == -ENOENT ? "" : "a");
+			break;
+		case -EINPROGRESS:
+			/* no info output */
+			break;
+		default:
+			dev_info(&urb->dev->dev,
+				 "urb %p may be in a error, status %d\n", urb,
+				 status);
+		}
+
+		list_del(&priv->list);
+		kfree(priv);
+		urb->hcpriv = NULL;
+
+		break;
+	}
+
+	return urb;
+}
+
+static void vhci_recv_ret_submit(struct vhci_device *vdev,
+				 struct usbip_header *pdu)
+{
+	struct usbip_device *ud = &vdev->ud;
+	struct urb *urb;
+
+	spin_lock(&vdev->priv_lock);
+	urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum);
+	spin_unlock(&vdev->priv_lock);
+
+	if (!urb) {
+		pr_err("cannot find a urb of seqnum %u\n", pdu->base.seqnum);
+		pr_info("max seqnum %d\n",
+			atomic_read(&the_controller->seqnum));
+		usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
+		return;
+	}
+
+	/* unpack the pdu to a urb */
+	usbip_pack_pdu(pdu, urb, USBIP_RET_SUBMIT, 0);
+
+	/* recv transfer buffer */
+	if (usbip_recv_xbuff(ud, urb) < 0)
+		return;
+
+	/* recv iso_packet_descriptor */
+	if (usbip_recv_iso(ud, urb) < 0)
+		return;
+
+	/* restore the padding in iso packets */
+	usbip_pad_iso(ud, urb);
+
+	if (usbip_dbg_flag_vhci_rx)
+		usbip_dump_urb(urb);
+
+	usbip_dbg_vhci_rx("now giveback urb %p\n", urb);
+
+	spin_lock(&the_controller->lock);
+	usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
+	spin_unlock(&the_controller->lock);
+
+	usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
+
+	usbip_dbg_vhci_rx("Leave\n");
+}
+
+static struct vhci_unlink *dequeue_pending_unlink(struct vhci_device *vdev,
+						  struct usbip_header *pdu)
+{
+	struct vhci_unlink *unlink, *tmp;
+
+	spin_lock(&vdev->priv_lock);
+
+	list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
+		pr_info("unlink->seqnum %lu\n", unlink->seqnum);
+		if (unlink->seqnum == pdu->base.seqnum) {
+			usbip_dbg_vhci_rx("found pending unlink, %lu\n",
+					  unlink->seqnum);
+			list_del(&unlink->list);
+
+			spin_unlock(&vdev->priv_lock);
+			return unlink;
+		}
+	}
+
+	spin_unlock(&vdev->priv_lock);
+
+	return NULL;
+}
+
+static void vhci_recv_ret_unlink(struct vhci_device *vdev,
+				 struct usbip_header *pdu)
+{
+	struct vhci_unlink *unlink;
+	struct urb *urb;
+
+	usbip_dump_header(pdu);
+
+	unlink = dequeue_pending_unlink(vdev, pdu);
+	if (!unlink) {
+		pr_info("cannot find the pending unlink %u\n",
+			pdu->base.seqnum);
+		return;
+	}
+
+	spin_lock(&vdev->priv_lock);
+	urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
+	spin_unlock(&vdev->priv_lock);
+
+	if (!urb) {
+		/*
+		 * I get the result of a unlink request. But, it seems that I
+		 * already received the result of its submit result and gave
+		 * back the URB.
+		 */
+		pr_info("the urb (seqnum %d) was already given back\n",
+			pdu->base.seqnum);
+	} else {
+		usbip_dbg_vhci_rx("now giveback urb %p\n", urb);
+
+		/* If unlink is successful, status is -ECONNRESET */
+		urb->status = pdu->u.ret_unlink.status;
+		pr_info("urb->status %d\n", urb->status);
+
+		spin_lock(&the_controller->lock);
+		usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
+		spin_unlock(&the_controller->lock);
+
+		usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
+				     urb->status);
+	}
+
+	kfree(unlink);
+}
+
+static int vhci_priv_tx_empty(struct vhci_device *vdev)
+{
+	int empty = 0;
+
+	spin_lock(&vdev->priv_lock);
+	empty = list_empty(&vdev->priv_rx);
+	spin_unlock(&vdev->priv_lock);
+
+	return empty;
+}
+
+/* recv a pdu */
+static void vhci_rx_pdu(struct usbip_device *ud)
+{
+	int ret;
+	struct usbip_header pdu;
+	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
+
+	usbip_dbg_vhci_rx("Enter\n");
+
+	memset(&pdu, 0, sizeof(pdu));
+
+	/* receive a pdu header */
+	ret = usbip_recv(ud->tcp_socket, &pdu, sizeof(pdu));
+	if (ret < 0) {
+		if (ret == -ECONNRESET)
+			pr_info("connection reset by peer\n");
+		else if (ret == -EAGAIN) {
+			/* ignore if connection was idle */
+			if (vhci_priv_tx_empty(vdev))
+				return;
+			pr_info("connection timed out with pending urbs\n");
+		} else if (ret != -ERESTARTSYS)
+			pr_info("xmit failed %d\n", ret);
+
+		usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
+		return;
+	}
+	if (ret == 0) {
+		pr_info("connection closed");
+		usbip_event_add(ud, VDEV_EVENT_DOWN);
+		return;
+	}
+	if (ret != sizeof(pdu)) {
+		pr_err("received pdu size is %d, should be %d\n", ret,
+		       (unsigned int)sizeof(pdu));
+		usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
+		return;
+	}
+
+	usbip_header_correct_endian(&pdu, 0);
+
+	if (usbip_dbg_flag_vhci_rx)
+		usbip_dump_header(&pdu);
+
+	switch (pdu.base.command) {
+	case USBIP_RET_SUBMIT:
+		vhci_recv_ret_submit(vdev, &pdu);
+		break;
+	case USBIP_RET_UNLINK:
+		vhci_recv_ret_unlink(vdev, &pdu);
+		break;
+	default:
+		/* NOT REACHED */
+		pr_err("unknown pdu %u\n", pdu.base.command);
+		usbip_dump_header(&pdu);
+		usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
+		break;
+	}
+}
+
+int vhci_rx_loop(void *data)
+{
+	struct usbip_device *ud = data;
+
+	while (!kthread_should_stop()) {
+		if (usbip_event_happened(ud))
+			break;
+
+		vhci_rx_pdu(ud);
+	}
+
+	return 0;
+}