diff options
Diffstat (limited to 'drivers/usb/usbip/stub_rx.c')
| -rw-r--r-- | drivers/usb/usbip/stub_rx.c | 594 |
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; +} |