Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / usb / usbip / stub_tx.c
diff --git a/kernel/drivers/usb/usbip/stub_tx.c b/kernel/drivers/usb/usbip/stub_tx.c
new file mode 100644 (file)
index 0000000..dbcabc9
--- /dev/null
@@ -0,0 +1,398 @@
+/*
+ * 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/socket.h>
+
+#include "usbip_common.h"
+#include "stub.h"
+
+static void stub_free_priv_and_urb(struct stub_priv *priv)
+{
+       struct urb *urb = priv->urb;
+
+       kfree(urb->setup_packet);
+       kfree(urb->transfer_buffer);
+       list_del(&priv->list);
+       kmem_cache_free(stub_priv_cache, priv);
+       usb_free_urb(urb);
+}
+
+/* be in spin_lock_irqsave(&sdev->priv_lock, flags) */
+void stub_enqueue_ret_unlink(struct stub_device *sdev, __u32 seqnum,
+                            __u32 status)
+{
+       struct stub_unlink *unlink;
+
+       unlink = kzalloc(sizeof(struct stub_unlink), GFP_ATOMIC);
+       if (!unlink) {
+               usbip_event_add(&sdev->ud, VDEV_EVENT_ERROR_MALLOC);
+               return;
+       }
+
+       unlink->seqnum = seqnum;
+       unlink->status = status;
+
+       list_add_tail(&unlink->list, &sdev->unlink_tx);
+}
+
+/**
+ * stub_complete - completion handler of a usbip urb
+ * @urb: pointer to the urb completed
+ *
+ * When a urb has completed, the USB core driver calls this function mostly in
+ * the interrupt context. To return the result of a urb, the completed urb is
+ * linked to the pending list of returning.
+ *
+ */
+void stub_complete(struct urb *urb)
+{
+       struct stub_priv *priv = (struct stub_priv *) urb->context;
+       struct stub_device *sdev = priv->sdev;
+       unsigned long flags;
+
+       usbip_dbg_stub_tx("complete! status %d\n", urb->status);
+
+       switch (urb->status) {
+       case 0:
+               /* OK */
+               break;
+       case -ENOENT:
+               dev_info(&urb->dev->dev,
+                        "stopped by a call to usb_kill_urb() because of cleaning up a virtual connection\n");
+               return;
+       case -ECONNRESET:
+               dev_info(&urb->dev->dev,
+                        "unlinked by a call to usb_unlink_urb()\n");
+               break;
+       case -EPIPE:
+               dev_info(&urb->dev->dev, "endpoint %d is stalled\n",
+                        usb_pipeendpoint(urb->pipe));
+               break;
+       case -ESHUTDOWN:
+               dev_info(&urb->dev->dev, "device removed?\n");
+               break;
+       default:
+               dev_info(&urb->dev->dev,
+                        "urb completion with non-zero status %d\n",
+                        urb->status);
+               break;
+       }
+
+       /* link a urb to the queue of tx. */
+       spin_lock_irqsave(&sdev->priv_lock, flags);
+       if (priv->unlinking) {
+               stub_enqueue_ret_unlink(sdev, priv->seqnum, urb->status);
+               stub_free_priv_and_urb(priv);
+       } else {
+               list_move_tail(&priv->list, &sdev->priv_tx);
+       }
+       spin_unlock_irqrestore(&sdev->priv_lock, flags);
+
+       /* wake up tx_thread */
+       wake_up(&sdev->tx_waitq);
+}
+
+static inline void setup_base_pdu(struct usbip_header_basic *base,
+                                 __u32 command, __u32 seqnum)
+{
+       base->command   = command;
+       base->seqnum    = seqnum;
+       base->devid     = 0;
+       base->ep        = 0;
+       base->direction = 0;
+}
+
+static void setup_ret_submit_pdu(struct usbip_header *rpdu, struct urb *urb)
+{
+       struct stub_priv *priv = (struct stub_priv *) urb->context;
+
+       setup_base_pdu(&rpdu->base, USBIP_RET_SUBMIT, priv->seqnum);
+       usbip_pack_pdu(rpdu, urb, USBIP_RET_SUBMIT, 1);
+}
+
+static void setup_ret_unlink_pdu(struct usbip_header *rpdu,
+                                struct stub_unlink *unlink)
+{
+       setup_base_pdu(&rpdu->base, USBIP_RET_UNLINK, unlink->seqnum);
+       rpdu->u.ret_unlink.status = unlink->status;
+}
+
+static struct stub_priv *dequeue_from_priv_tx(struct stub_device *sdev)
+{
+       unsigned long flags;
+       struct stub_priv *priv, *tmp;
+
+       spin_lock_irqsave(&sdev->priv_lock, flags);
+
+       list_for_each_entry_safe(priv, tmp, &sdev->priv_tx, list) {
+               list_move_tail(&priv->list, &sdev->priv_free);
+               spin_unlock_irqrestore(&sdev->priv_lock, flags);
+               return priv;
+       }
+
+       spin_unlock_irqrestore(&sdev->priv_lock, flags);
+
+       return NULL;
+}
+
+static int stub_send_ret_submit(struct stub_device *sdev)
+{
+       unsigned long flags;
+       struct stub_priv *priv, *tmp;
+
+       struct msghdr msg;
+       size_t txsize;
+
+       size_t total_size = 0;
+
+       while ((priv = dequeue_from_priv_tx(sdev)) != NULL) {
+               int ret;
+               struct urb *urb = priv->urb;
+               struct usbip_header pdu_header;
+               struct usbip_iso_packet_descriptor *iso_buffer = NULL;
+               struct kvec *iov = NULL;
+               int iovnum = 0;
+
+               txsize = 0;
+               memset(&pdu_header, 0, sizeof(pdu_header));
+               memset(&msg, 0, sizeof(msg));
+
+               if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS)
+                       iovnum = 2 + urb->number_of_packets;
+               else
+                       iovnum = 2;
+
+               iov = kcalloc(iovnum, sizeof(struct kvec), GFP_KERNEL);
+
+               if (!iov) {
+                       usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_MALLOC);
+                       return -1;
+               }
+
+               iovnum = 0;
+
+               /* 1. setup usbip_header */
+               setup_ret_submit_pdu(&pdu_header, urb);
+               usbip_dbg_stub_tx("setup txdata seqnum: %d urb: %p\n",
+                                 pdu_header.base.seqnum, urb);
+               usbip_header_correct_endian(&pdu_header, 1);
+
+               iov[iovnum].iov_base = &pdu_header;
+               iov[iovnum].iov_len  = sizeof(pdu_header);
+               iovnum++;
+               txsize += sizeof(pdu_header);
+
+               /* 2. setup transfer buffer */
+               if (usb_pipein(urb->pipe) &&
+                   usb_pipetype(urb->pipe) != PIPE_ISOCHRONOUS &&
+                   urb->actual_length > 0) {
+                       iov[iovnum].iov_base = urb->transfer_buffer;
+                       iov[iovnum].iov_len  = urb->actual_length;
+                       iovnum++;
+                       txsize += urb->actual_length;
+               } else if (usb_pipein(urb->pipe) &&
+                          usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
+                       /*
+                        * For isochronous packets: actual length is the sum of
+                        * the actual length of the individual, packets, but as
+                        * the packet offsets are not changed there will be
+                        * padding between the packets. To optimally use the
+                        * bandwidth the padding is not transmitted.
+                        */
+
+                       int i;
+
+                       for (i = 0; i < urb->number_of_packets; i++) {
+                               iov[iovnum].iov_base = urb->transfer_buffer +
+                                       urb->iso_frame_desc[i].offset;
+                               iov[iovnum].iov_len =
+                                       urb->iso_frame_desc[i].actual_length;
+                               iovnum++;
+                               txsize += urb->iso_frame_desc[i].actual_length;
+                       }
+
+                       if (txsize != sizeof(pdu_header) + urb->actual_length) {
+                               dev_err(&sdev->interface->dev,
+                                       "actual length of urb %d does not match iso packet sizes %zu\n",
+                                       urb->actual_length,
+                                       txsize-sizeof(pdu_header));
+                               kfree(iov);
+                               usbip_event_add(&sdev->ud,
+                                               SDEV_EVENT_ERROR_TCP);
+                          return -1;
+                       }
+               }
+
+               /* 3. setup iso_packet_descriptor */
+               if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
+                       ssize_t len = 0;
+
+                       iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len);
+                       if (!iso_buffer) {
+                               usbip_event_add(&sdev->ud,
+                                               SDEV_EVENT_ERROR_MALLOC);
+                               kfree(iov);
+                               return -1;
+                       }
+
+                       iov[iovnum].iov_base = iso_buffer;
+                       iov[iovnum].iov_len  = len;
+                       txsize += len;
+                       iovnum++;
+               }
+
+               ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg,
+                                               iov,  iovnum, txsize);
+               if (ret != txsize) {
+                       dev_err(&sdev->interface->dev,
+                               "sendmsg failed!, retval %d for %zd\n",
+                               ret, txsize);
+                       kfree(iov);
+                       kfree(iso_buffer);
+                       usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);
+                       return -1;
+               }
+
+               kfree(iov);
+               kfree(iso_buffer);
+
+               total_size += txsize;
+       }
+
+       spin_lock_irqsave(&sdev->priv_lock, flags);
+       list_for_each_entry_safe(priv, tmp, &sdev->priv_free, list) {
+               stub_free_priv_and_urb(priv);
+       }
+       spin_unlock_irqrestore(&sdev->priv_lock, flags);
+
+       return total_size;
+}
+
+static struct stub_unlink *dequeue_from_unlink_tx(struct stub_device *sdev)
+{
+       unsigned long flags;
+       struct stub_unlink *unlink, *tmp;
+
+       spin_lock_irqsave(&sdev->priv_lock, flags);
+
+       list_for_each_entry_safe(unlink, tmp, &sdev->unlink_tx, list) {
+               list_move_tail(&unlink->list, &sdev->unlink_free);
+               spin_unlock_irqrestore(&sdev->priv_lock, flags);
+               return unlink;
+       }
+
+       spin_unlock_irqrestore(&sdev->priv_lock, flags);
+
+       return NULL;
+}
+
+static int stub_send_ret_unlink(struct stub_device *sdev)
+{
+       unsigned long flags;
+       struct stub_unlink *unlink, *tmp;
+
+       struct msghdr msg;
+       struct kvec iov[1];
+       size_t txsize;
+
+       size_t total_size = 0;
+
+       while ((unlink = dequeue_from_unlink_tx(sdev)) != NULL) {
+               int ret;
+               struct usbip_header pdu_header;
+
+               txsize = 0;
+               memset(&pdu_header, 0, sizeof(pdu_header));
+               memset(&msg, 0, sizeof(msg));
+               memset(&iov, 0, sizeof(iov));
+
+               usbip_dbg_stub_tx("setup ret unlink %lu\n", unlink->seqnum);
+
+               /* 1. setup usbip_header */
+               setup_ret_unlink_pdu(&pdu_header, unlink);
+               usbip_header_correct_endian(&pdu_header, 1);
+
+               iov[0].iov_base = &pdu_header;
+               iov[0].iov_len  = sizeof(pdu_header);
+               txsize += sizeof(pdu_header);
+
+               ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, iov,
+                                    1, txsize);
+               if (ret != txsize) {
+                       dev_err(&sdev->interface->dev,
+                               "sendmsg failed!, retval %d for %zd\n",
+                               ret, txsize);
+                       usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);
+                       return -1;
+               }
+
+               usbip_dbg_stub_tx("send txdata\n");
+               total_size += txsize;
+       }
+
+       spin_lock_irqsave(&sdev->priv_lock, flags);
+
+       list_for_each_entry_safe(unlink, tmp, &sdev->unlink_free, list) {
+               list_del(&unlink->list);
+               kfree(unlink);
+       }
+
+       spin_unlock_irqrestore(&sdev->priv_lock, flags);
+
+       return total_size;
+}
+
+int stub_tx_loop(void *data)
+{
+       struct usbip_device *ud = data;
+       struct stub_device *sdev = container_of(ud, struct stub_device, ud);
+
+       while (!kthread_should_stop()) {
+               if (usbip_event_happened(ud))
+                       break;
+
+               /*
+                * send_ret_submit comes earlier than send_ret_unlink.  stub_rx
+                * looks at only priv_init queue. If the completion of a URB is
+                * earlier than the receive of CMD_UNLINK, priv is moved to
+                * priv_tx queue and stub_rx does not find the target priv. In
+                * this case, vhci_rx receives the result of the submit request
+                * and then receives the result of the unlink request. The
+                * result of the submit is given back to the usbcore as the
+                * completion of the unlink request. The request of the
+                * unlink is ignored. This is ok because a driver who calls
+                * usb_unlink_urb() understands the unlink was too late by
+                * getting the status of the given-backed URB which has the
+                * status of usb_submit_urb().
+                */
+               if (stub_send_ret_submit(sdev) < 0)
+                       break;
+
+               if (stub_send_ret_unlink(sdev) < 0)
+                       break;
+
+               wait_event_interruptible(sdev->tx_waitq,
+                                        (!list_empty(&sdev->priv_tx) ||
+                                         !list_empty(&sdev->unlink_tx) ||
+                                         kthread_should_stop()));
+       }
+
+       return 0;
+}