/* * $Id: stub_tx.c 66 2008-04-20 13:19:42Z hirofuchi $ * * 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 "usbip_common.h"#include "stub.h"static void stub_free_priv_and_urb(struct stub_priv *priv){	struct urb *urb = priv->urb;	if (urb->setup_packet)		kfree(urb->setup_packet);	if (urb->transfer_buffer)		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) {		uerr("alloc stub_unlink\n");		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 * @regs: * * 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. * */#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,21)void stub_complete(struct urb *urb)#elsevoid stub_complete(struct urb *urb, struct pt_regs *regs)#endif{	struct stub_priv *priv = (struct stub_priv *) urb->context;	struct stub_device *sdev = priv->sdev;	unsigned long flags;	dbg_stub_tx("complete! status %d\n", urb->status);	switch (urb->status) {		case 0:			/* OK */			break;		case -ENOENT:			uinfo("stopped by a call of usb_kill_urb()"					"because of cleaning up a virtual connection\n");			return;		case -ECONNRESET:			uinfo("unlinked by a call of usb_unlink_urb()\n");			break;		case -EPIPE:			uinfo("endpoint %d is stalled\n", usb_pipeendpoint(urb->pipe));			break;		case -ESHUTDOWN:			uinfo("device removed?\n");			break;		default:			uinfo("urb completion with non-zero status %d\n", urb->status);	}	/* 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);}/*-------------------------------------------------------------------------*//* fill PDU */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;}/*-------------------------------------------------------------------------*//* send RET_SUBMIT */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;	struct kvec iov[3];	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;		void *iso_buffer = NULL;		txsize = 0;		memset(&pdu_header, 0, sizeof(pdu_header));		memset(&msg, 0, sizeof(msg));		memset(&iov, 0, sizeof(iov));		dbg_stub_tx("setup txdata urb %p\n", urb);		/* 1. setup usbip_header */		setup_ret_submit_pdu(&pdu_header, urb);		usbip_header_correct_endian(&pdu_header, 1);		iov[0].iov_base = &pdu_header;		iov[0].iov_len  = sizeof(pdu_header);		txsize += sizeof(pdu_header);		/* 2. setup transfer buffer */		if (usb_pipein(urb->pipe) && urb->actual_length > 0) {			iov[1].iov_base = urb->transfer_buffer;			iov[1].iov_len  = urb->actual_length;			txsize += urb->actual_length;		}		/* 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);				return -1;			}			iov[2].iov_base = iso_buffer;			iov[2].iov_len  = len;			txsize += len;		}		ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, iov, 3, txsize);		if (ret != txsize) {			uerr("sendmsg failed!, retval %d for %zd\n", ret, txsize);			if (iso_buffer)				kfree(iso_buffer);			usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);			return -1;		}		if (iso_buffer)			kfree(iso_buffer);		dbg_stub_tx("send txdata\n");		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;}/*-------------------------------------------------------------------------*//* send RET_UNLINK */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));		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) {			uerr("sendmsg failed!, retval %d for %zd\n", ret, txsize);			usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);			return -1;		}		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;}/*-------------------------------------------------------------------------*/void stub_tx_loop(struct usbip_task *ut){	struct usbip_device *ud = container_of(ut, struct usbip_device, tcp_tx);	struct stub_device *sdev = container_of(ud, struct stub_device, ud);	while (1) {		if (signal_pending(current)) {			dbg_stub_tx("signal catched\n");			break;		}		if (usbip_event_happend(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)));	}}