/* * $Id: stub_rx.c 12 2007-05-27 16:11:48Z hirofuchi $ * * Copyright (C) 2003-2007 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 "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 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)		uinfo("clear_halt error: devnum %d endp %d, %d\n",				urb->dev->devnum, target_endp, ret);	else		uinfo("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);	dbg_stub_rx("set_interface: inf %u alt %u\n", interface, alternate);	ret = usb_set_interface(urb->dev, interface, alternate);	if (ret < 0)		uinfo("set_interface error: inf %u alt %u, %d\n",				interface, alternate, ret);	else		uinfo("set_interface done: inf %u alt %u\n", interface, alternate);	return ret;}static int tweak_set_configuration_cmd(struct urb *urb){	struct usb_ctrlrequest *req;	__u16 config;	info("set_configuration is not fully supported yet\n");	req = (struct usb_ctrlrequest *) urb->setup_packet;	config = le16_to_cpu(req->wValue);	uinfo("set_configuration: devnum %d %d\n", urb->dev->devnum, config);#if 0	return usb_set_configuration(urb->dev, config);#endif	return 0;}/* * clear_halt, set_interface, and set_configuration require special tricks. * TODO: set_configuration. but I have never seen a multi-config device. */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		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){	struct list_head *listhead = &sdev->priv_init;	struct list_head *ptr;	unsigned long flags;	struct stub_priv *priv;	spin_lock_irqsave(&sdev->priv_lock, flags);	for (ptr = listhead->next; ptr != listhead; ptr = ptr->next) {		priv = list_entry(ptr, struct stub_priv, list);		if (priv->seqnum == pdu->u.cmd_unlink.seqnum) {			int ret;			uinfo("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)				uerr("faild to unlink a urb %p, ret %d\n", priv->urb, ret);			return 0;		}	}	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 bus = interface_to_busnum(sdev->interface);	int dev = interface_to_devnum(sdev->interface);	if (pdu->base.busnum == bus && pdu->base.devnum == dev) {		spin_lock(&ud->lock);		if (ud->status == SDEV_ST_USED) {			/* A request is valid. */			spin_unlock(&ud->lock);			return 1;		}		spin_unlock(&ud->lock);	}	return 0;}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_alloc(stub_priv_cache, GFP_ATOMIC);	if (!priv) {		uerr("alloc stub_priv\n");		spin_unlock_irqrestore(&sdev->priv_lock, flags);		usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);		return NULL;	}	memset(priv, 0, sizeof(struct stub_priv));	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 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;	priv = stub_priv_alloc(sdev, pdu);	if (!priv)		return;	/* setup a urb */	if (usb_pipeisoc(pdu->base.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) {		uerr("malloc urb\n");		usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);		return;	}	/* set priv->urb->transfer_buffer */	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) {			uerr("malloc x_buff\n");			usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);			return;		}	}	/* set priv->urb->setup_packet */	priv->urb->setup_packet = kzalloc(8, GFP_KERNEL);	if (!priv->urb->setup_packet) {		uerr("allocate setup_packet\n");		usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);		return;	}	memcpy(priv->urb->setup_packet, &pdu->u.cmd_submit.setup, 8);	/* set other members from the base header of pdu */	priv->urb->context                = (void *) priv;	priv->urb->dev                    = interface_to_usbdev(sdev->interface);	priv->urb->pipe                   = pdu->base.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);	/* urb is now ready to submit */	ret = usb_submit_urb(priv->urb, GFP_KERNEL);	if (ret == 0)		dbg_stub_rx("submit urb ok, seqnum %u\n", pdu->base.seqnum);	else {		uerr("submit_urb error, %d\n", ret);		/*		 * Pessimistic.		 * This connection will be discarded.		 */		usbip_event_add(ud, SDEV_EVENT_ERROR_SUBMIT);	}	dbg_stub_rx("Leave\n");	return;}/* 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);	dbg_stub_rx("Enter\n");	memset(&pdu, 0, sizeof(pdu));	/* 1. receive a pdu header */	ret = usbip_xmit(0, ud->tcp_socket, (char *) &pdu, sizeof(pdu),0);	if (ret != sizeof(pdu)) {		uerr("recv a header, %d\n", ret);		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);		return;	}	usbip_header_correct_endian(&pdu, 0);	if (dbg_flag_stub_rx)		usbip_dump_header(&pdu);	if (!valid_request(sdev, &pdu)) {		uerr("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 */			uerr("unknown pdu\n");			usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);			return;	}}void stub_rx_loop(struct usbip_task *ut){	struct usbip_device *ud = container_of(ut, struct usbip_device, tcp_rx);	while (1) {		if (signal_pending(current)) {			dbg_stub_rx("signal caught!\n");			break;		}		if (usbip_event_happend(ud))			break;		stub_rx_pdu(ud);	}}