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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/usb/usbip/vhci_rx.c
Initial import
Diffstat (limited to 'drivers/usb/usbip/vhci_rx.c')
-rw-r--r--drivers/usb/usbip/vhci_rx.c268
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 000000000..00e4a5430
--- /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;
+}