1 files changed, 594 insertions, 0 deletions

diff --git a/drivers/usb/usbip/stub_rx.c b/drivers/usb/usbip/stub_rx.c
new file mode 100644
index 000000000000..00e475c51a12
--- /dev/null
+++ b/drivers/usb/usbip/stub_rx.c
@@ -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;
+}