Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / usb / usbip / stub_rx.c
diff --git a/kernel/drivers/usb/usbip/stub_rx.c b/kernel/drivers/usb/usbip/stub_rx.c
new file mode 100644 (file)
index 0000000..00e475c
--- /dev/null
@@ -0,0 +1,594 @@
+/*
+ * 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 <asm/byteorder.h>
+#include <linux/kthread.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+
+#include "usbip_common.h"
+#include "stub.h"
+
+static int is_clear_halt_cmd(struct urb *urb)
+{
+       struct usb_ctrlrequest *req;
+
+       req = (struct usb_ctrlrequest *) urb->setup_packet;
+
+        return (req->bRequest == USB_REQ_CLEAR_FEATURE) &&
+                (req->bRequestType == USB_RECIP_ENDPOINT) &&
+                (req->wValue == USB_ENDPOINT_HALT);
+}
+
+static int is_set_interface_cmd(struct urb *urb)
+{
+       struct usb_ctrlrequest *req;
+
+       req = (struct usb_ctrlrequest *) urb->setup_packet;
+
+       return (req->bRequest == USB_REQ_SET_INTERFACE) &&
+               (req->bRequestType == USB_RECIP_INTERFACE);
+}
+
+static int is_set_configuration_cmd(struct urb *urb)
+{
+       struct usb_ctrlrequest *req;
+
+       req = (struct usb_ctrlrequest *) urb->setup_packet;
+
+       return (req->bRequest == USB_REQ_SET_CONFIGURATION) &&
+               (req->bRequestType == USB_RECIP_DEVICE);
+}
+
+static int is_reset_device_cmd(struct urb *urb)
+{
+       struct usb_ctrlrequest *req;
+       __u16 value;
+       __u16 index;
+
+       req = (struct usb_ctrlrequest *) urb->setup_packet;
+       value = le16_to_cpu(req->wValue);
+       index = le16_to_cpu(req->wIndex);
+
+       if ((req->bRequest == USB_REQ_SET_FEATURE) &&
+           (req->bRequestType == USB_RT_PORT) &&
+           (value == USB_PORT_FEAT_RESET)) {
+               usbip_dbg_stub_rx("reset_device_cmd, port %u\n", index);
+               return 1;
+       } else
+               return 0;
+}
+
+static int tweak_clear_halt_cmd(struct urb *urb)
+{
+       struct usb_ctrlrequest *req;
+       int target_endp;
+       int target_dir;
+       int target_pipe;
+       int ret;
+
+       req = (struct usb_ctrlrequest *) urb->setup_packet;
+
+       /*
+        * The stalled endpoint is specified in the wIndex value. The endpoint
+        * of the urb is the target of this clear_halt request (i.e., control
+        * endpoint).
+        */
+       target_endp = le16_to_cpu(req->wIndex) & 0x000f;
+
+       /* the stalled endpoint direction is IN or OUT?. USB_DIR_IN is 0x80.  */
+       target_dir = le16_to_cpu(req->wIndex) & 0x0080;
+
+       if (target_dir)
+               target_pipe = usb_rcvctrlpipe(urb->dev, target_endp);
+       else
+               target_pipe = usb_sndctrlpipe(urb->dev, target_endp);
+
+       ret = usb_clear_halt(urb->dev, target_pipe);
+       if (ret < 0)
+               dev_err(&urb->dev->dev,
+                       "usb_clear_halt error: devnum %d endp %d ret %d\n",
+                       urb->dev->devnum, target_endp, ret);
+       else
+               dev_info(&urb->dev->dev,
+                        "usb_clear_halt done: devnum %d endp %d\n",
+                        urb->dev->devnum, target_endp);
+
+       return ret;
+}
+
+static int tweak_set_interface_cmd(struct urb *urb)
+{
+       struct usb_ctrlrequest *req;
+       __u16 alternate;
+       __u16 interface;
+       int ret;
+
+       req = (struct usb_ctrlrequest *) urb->setup_packet;
+       alternate = le16_to_cpu(req->wValue);
+       interface = le16_to_cpu(req->wIndex);
+
+       usbip_dbg_stub_rx("set_interface: inf %u alt %u\n",
+                         interface, alternate);
+
+       ret = usb_set_interface(urb->dev, interface, alternate);
+       if (ret < 0)
+               dev_err(&urb->dev->dev,
+                       "usb_set_interface error: inf %u alt %u ret %d\n",
+                       interface, alternate, ret);
+       else
+               dev_info(&urb->dev->dev,
+                       "usb_set_interface done: inf %u alt %u\n",
+                       interface, alternate);
+
+       return ret;
+}
+
+static int tweak_set_configuration_cmd(struct urb *urb)
+{
+       struct stub_priv *priv = (struct stub_priv *) urb->context;
+       struct stub_device *sdev = priv->sdev;
+       struct usb_ctrlrequest *req;
+       __u16 config;
+       int err;
+
+       req = (struct usb_ctrlrequest *) urb->setup_packet;
+       config = le16_to_cpu(req->wValue);
+
+       err = usb_set_configuration(sdev->udev, config);
+       if (err && err != -ENODEV)
+               dev_err(&sdev->udev->dev, "can't set config #%d, error %d\n",
+                       config, err);
+       return 0;
+}
+
+static int tweak_reset_device_cmd(struct urb *urb)
+{
+       struct stub_priv *priv = (struct stub_priv *) urb->context;
+       struct stub_device *sdev = priv->sdev;
+
+       dev_info(&urb->dev->dev, "usb_queue_reset_device\n");
+
+       /*
+        * With the implementation of pre_reset and post_reset the driver no
+        * longer unbinds. This allows the use of synchronous reset.
+        */
+
+       if (usb_lock_device_for_reset(sdev->udev, sdev->interface) < 0) {
+               dev_err(&urb->dev->dev, "could not obtain lock to reset device\n");
+               return 0;
+       }
+       usb_reset_device(sdev->udev);
+       usb_unlock_device(sdev->udev);
+
+       return 0;
+}
+
+/*
+ * clear_halt, set_interface, and set_configuration require special tricks.
+ */
+static void tweak_special_requests(struct urb *urb)
+{
+       if (!urb || !urb->setup_packet)
+               return;
+
+       if (usb_pipetype(urb->pipe) != PIPE_CONTROL)
+               return;
+
+       if (is_clear_halt_cmd(urb))
+               /* tweak clear_halt */
+                tweak_clear_halt_cmd(urb);
+
+       else if (is_set_interface_cmd(urb))
+               /* tweak set_interface */
+               tweak_set_interface_cmd(urb);
+
+       else if (is_set_configuration_cmd(urb))
+               /* tweak set_configuration */
+               tweak_set_configuration_cmd(urb);
+
+       else if (is_reset_device_cmd(urb))
+               tweak_reset_device_cmd(urb);
+       else
+               usbip_dbg_stub_rx("no need to tweak\n");
+}
+
+/*
+ * stub_recv_unlink() unlinks the URB by a call to usb_unlink_urb().
+ * By unlinking the urb asynchronously, stub_rx can continuously
+ * process coming urbs.  Even if the urb is unlinked, its completion
+ * handler will be called and stub_tx will send a return pdu.
+ *
+ * See also comments about unlinking strategy in vhci_hcd.c.
+ */
+static int stub_recv_cmd_unlink(struct stub_device *sdev,
+                               struct usbip_header *pdu)
+{
+       int ret;
+       unsigned long flags;
+       struct stub_priv *priv;
+
+       spin_lock_irqsave(&sdev->priv_lock, flags);
+
+       list_for_each_entry(priv, &sdev->priv_init, list) {
+               if (priv->seqnum != pdu->u.cmd_unlink.seqnum)
+                       continue;
+
+               dev_info(&priv->urb->dev->dev, "unlink urb %p\n",
+                        priv->urb);
+
+               /*
+                * This matched urb is not completed yet (i.e., be in
+                * flight in usb hcd hardware/driver). Now we are
+                * cancelling it. The unlinking flag means that we are
+                * now not going to return the normal result pdu of a
+                * submission request, but going to return a result pdu
+                * of the unlink request.
+                */
+               priv->unlinking = 1;
+
+               /*
+                * In the case that unlinking flag is on, prev->seqnum
+                * is changed from the seqnum of the cancelling urb to
+                * the seqnum of the unlink request. This will be used
+                * to make the result pdu of the unlink request.
+                */
+               priv->seqnum = pdu->base.seqnum;
+
+               spin_unlock_irqrestore(&sdev->priv_lock, flags);
+
+               /*
+                * usb_unlink_urb() is now out of spinlocking to avoid
+                * spinlock recursion since stub_complete() is
+                * sometimes called in this context but not in the
+                * interrupt context.  If stub_complete() is executed
+                * before we call usb_unlink_urb(), usb_unlink_urb()
+                * will return an error value. In this case, stub_tx
+                * will return the result pdu of this unlink request
+                * though submission is completed and actual unlinking
+                * is not executed. OK?
+                */
+               /* In the above case, urb->status is not -ECONNRESET,
+                * so a driver in a client host will know the failure
+                * of the unlink request ?
+                */
+               ret = usb_unlink_urb(priv->urb);
+               if (ret != -EINPROGRESS)
+                       dev_err(&priv->urb->dev->dev,
+                               "failed to unlink a urb %p, ret %d\n",
+                               priv->urb, ret);
+
+               return 0;
+       }
+
+       usbip_dbg_stub_rx("seqnum %d is not pending\n",
+                         pdu->u.cmd_unlink.seqnum);
+
+       /*
+        * The urb of the unlink target is not found in priv_init queue. It was
+        * already completed and its results is/was going to be sent by a
+        * CMD_RET pdu. In this case, usb_unlink_urb() is not needed. We only
+        * return the completeness of this unlink request to vhci_hcd.
+        */
+       stub_enqueue_ret_unlink(sdev, pdu->base.seqnum, 0);
+
+       spin_unlock_irqrestore(&sdev->priv_lock, flags);
+
+       return 0;
+}
+
+static int valid_request(struct stub_device *sdev, struct usbip_header *pdu)
+{
+       struct usbip_device *ud = &sdev->ud;
+       int valid = 0;
+
+       if (pdu->base.devid == sdev->devid) {
+               spin_lock_irq(&ud->lock);
+               if (ud->status == SDEV_ST_USED) {
+                       /* A request is valid. */
+                       valid = 1;
+               }
+               spin_unlock_irq(&ud->lock);
+       }
+
+       return valid;
+}
+
+static struct stub_priv *stub_priv_alloc(struct stub_device *sdev,
+                                        struct usbip_header *pdu)
+{
+       struct stub_priv *priv;
+       struct usbip_device *ud = &sdev->ud;
+       unsigned long flags;
+
+       spin_lock_irqsave(&sdev->priv_lock, flags);
+
+       priv = kmem_cache_zalloc(stub_priv_cache, GFP_ATOMIC);
+       if (!priv) {
+               dev_err(&sdev->interface->dev, "alloc stub_priv\n");
+               spin_unlock_irqrestore(&sdev->priv_lock, flags);
+               usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
+               return NULL;
+       }
+
+       priv->seqnum = pdu->base.seqnum;
+       priv->sdev = sdev;
+
+       /*
+        * After a stub_priv is linked to a list_head,
+        * our error handler can free allocated data.
+        */
+       list_add_tail(&priv->list, &sdev->priv_init);
+
+       spin_unlock_irqrestore(&sdev->priv_lock, flags);
+
+       return priv;
+}
+
+static int get_pipe(struct stub_device *sdev, int epnum, int dir)
+{
+       struct usb_device *udev = sdev->udev;
+       struct usb_host_endpoint *ep;
+       struct usb_endpoint_descriptor *epd = NULL;
+
+       if (dir == USBIP_DIR_IN)
+               ep = udev->ep_in[epnum & 0x7f];
+       else
+               ep = udev->ep_out[epnum & 0x7f];
+       if (!ep) {
+               dev_err(&sdev->interface->dev, "no such endpoint?, %d\n",
+                       epnum);
+               BUG();
+       }
+
+       epd = &ep->desc;
+       if (usb_endpoint_xfer_control(epd)) {
+               if (dir == USBIP_DIR_OUT)
+                       return usb_sndctrlpipe(udev, epnum);
+               else
+                       return usb_rcvctrlpipe(udev, epnum);
+       }
+
+       if (usb_endpoint_xfer_bulk(epd)) {
+               if (dir == USBIP_DIR_OUT)
+                       return usb_sndbulkpipe(udev, epnum);
+               else
+                       return usb_rcvbulkpipe(udev, epnum);
+       }
+
+       if (usb_endpoint_xfer_int(epd)) {
+               if (dir == USBIP_DIR_OUT)
+                       return usb_sndintpipe(udev, epnum);
+               else
+                       return usb_rcvintpipe(udev, epnum);
+       }
+
+       if (usb_endpoint_xfer_isoc(epd)) {
+               if (dir == USBIP_DIR_OUT)
+                       return usb_sndisocpipe(udev, epnum);
+               else
+                       return usb_rcvisocpipe(udev, epnum);
+       }
+
+       /* NOT REACHED */
+       dev_err(&sdev->interface->dev, "get pipe, epnum %d\n", epnum);
+       return 0;
+}
+
+static void masking_bogus_flags(struct urb *urb)
+{
+       int                             xfertype;
+       struct usb_device               *dev;
+       struct usb_host_endpoint        *ep;
+       int                             is_out;
+       unsigned int    allowed;
+
+       if (!urb || urb->hcpriv || !urb->complete)
+               return;
+       dev = urb->dev;
+       if ((!dev) || (dev->state < USB_STATE_UNAUTHENTICATED))
+               return;
+
+       ep = (usb_pipein(urb->pipe) ? dev->ep_in : dev->ep_out)
+               [usb_pipeendpoint(urb->pipe)];
+       if (!ep)
+               return;
+
+       xfertype = usb_endpoint_type(&ep->desc);
+       if (xfertype == USB_ENDPOINT_XFER_CONTROL) {
+               struct usb_ctrlrequest *setup =
+                       (struct usb_ctrlrequest *) urb->setup_packet;
+
+               if (!setup)
+                       return;
+               is_out = !(setup->bRequestType & USB_DIR_IN) ||
+                       !setup->wLength;
+       } else {
+               is_out = usb_endpoint_dir_out(&ep->desc);
+       }
+
+       /* enforce simple/standard policy */
+       allowed = (URB_NO_TRANSFER_DMA_MAP | URB_NO_INTERRUPT |
+                  URB_DIR_MASK | URB_FREE_BUFFER);
+       switch (xfertype) {
+       case USB_ENDPOINT_XFER_BULK:
+               if (is_out)
+                       allowed |= URB_ZERO_PACKET;
+               /* FALLTHROUGH */
+       case USB_ENDPOINT_XFER_CONTROL:
+               allowed |= URB_NO_FSBR; /* only affects UHCI */
+               /* FALLTHROUGH */
+       default:                        /* all non-iso endpoints */
+               if (!is_out)
+                       allowed |= URB_SHORT_NOT_OK;
+               break;
+       case USB_ENDPOINT_XFER_ISOC:
+               allowed |= URB_ISO_ASAP;
+               break;
+       }
+       urb->transfer_flags &= allowed;
+}
+
+static void stub_recv_cmd_submit(struct stub_device *sdev,
+                                struct usbip_header *pdu)
+{
+       int ret;
+       struct stub_priv *priv;
+       struct usbip_device *ud = &sdev->ud;
+       struct usb_device *udev = sdev->udev;
+       int pipe = get_pipe(sdev, pdu->base.ep, pdu->base.direction);
+
+       priv = stub_priv_alloc(sdev, pdu);
+       if (!priv)
+               return;
+
+       /* setup a urb */
+       if (usb_pipeisoc(pipe))
+               priv->urb = usb_alloc_urb(pdu->u.cmd_submit.number_of_packets,
+                                         GFP_KERNEL);
+       else
+               priv->urb = usb_alloc_urb(0, GFP_KERNEL);
+
+       if (!priv->urb) {
+               dev_err(&sdev->interface->dev, "malloc urb\n");
+               usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
+               return;
+       }
+
+       /* allocate urb transfer buffer, if needed */
+       if (pdu->u.cmd_submit.transfer_buffer_length > 0) {
+               priv->urb->transfer_buffer =
+                       kzalloc(pdu->u.cmd_submit.transfer_buffer_length,
+                               GFP_KERNEL);
+               if (!priv->urb->transfer_buffer) {
+                       usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
+                       return;
+               }
+       }
+
+       /* copy urb setup packet */
+       priv->urb->setup_packet = kmemdup(&pdu->u.cmd_submit.setup, 8,
+                                         GFP_KERNEL);
+       if (!priv->urb->setup_packet) {
+               dev_err(&sdev->interface->dev, "allocate setup_packet\n");
+               usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
+               return;
+       }
+
+       /* set other members from the base header of pdu */
+       priv->urb->context                = (void *) priv;
+       priv->urb->dev                    = udev;
+       priv->urb->pipe                   = pipe;
+       priv->urb->complete               = stub_complete;
+
+       usbip_pack_pdu(pdu, priv->urb, USBIP_CMD_SUBMIT, 0);
+
+
+       if (usbip_recv_xbuff(ud, priv->urb) < 0)
+               return;
+
+       if (usbip_recv_iso(ud, priv->urb) < 0)
+               return;
+
+       /* no need to submit an intercepted request, but harmless? */
+       tweak_special_requests(priv->urb);
+
+       masking_bogus_flags(priv->urb);
+       /* urb is now ready to submit */
+       ret = usb_submit_urb(priv->urb, GFP_KERNEL);
+
+       if (ret == 0)
+               usbip_dbg_stub_rx("submit urb ok, seqnum %u\n",
+                                 pdu->base.seqnum);
+       else {
+               dev_err(&sdev->interface->dev, "submit_urb error, %d\n", ret);
+               usbip_dump_header(pdu);
+               usbip_dump_urb(priv->urb);
+
+               /*
+                * Pessimistic.
+                * This connection will be discarded.
+                */
+               usbip_event_add(ud, SDEV_EVENT_ERROR_SUBMIT);
+       }
+
+       usbip_dbg_stub_rx("Leave\n");
+}
+
+/* recv a pdu */
+static void stub_rx_pdu(struct usbip_device *ud)
+{
+       int ret;
+       struct usbip_header pdu;
+       struct stub_device *sdev = container_of(ud, struct stub_device, ud);
+       struct device *dev = &sdev->udev->dev;
+
+       usbip_dbg_stub_rx("Enter\n");
+
+       memset(&pdu, 0, sizeof(pdu));
+
+       /* receive a pdu header */
+       ret = usbip_recv(ud->tcp_socket, &pdu, sizeof(pdu));
+       if (ret != sizeof(pdu)) {
+               dev_err(dev, "recv a header, %d\n", ret);
+               usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
+               return;
+       }
+
+       usbip_header_correct_endian(&pdu, 0);
+
+       if (usbip_dbg_flag_stub_rx)
+               usbip_dump_header(&pdu);
+
+       if (!valid_request(sdev, &pdu)) {
+               dev_err(dev, "recv invalid request\n");
+               usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
+               return;
+       }
+
+       switch (pdu.base.command) {
+       case USBIP_CMD_UNLINK:
+               stub_recv_cmd_unlink(sdev, &pdu);
+               break;
+
+       case USBIP_CMD_SUBMIT:
+               stub_recv_cmd_submit(sdev, &pdu);
+               break;
+
+       default:
+               /* NOTREACHED */
+               dev_err(dev, "unknown pdu\n");
+               usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
+               break;
+       }
+}
+
+int stub_rx_loop(void *data)
+{
+       struct usbip_device *ud = data;
+
+       while (!kthread_should_stop()) {
+               if (usbip_event_happened(ud))
+                       break;
+
+               stub_rx_pdu(ud);
+       }
+
+       return 0;
+}