[mirror_ubuntu-artful-kernel.git] / drivers / usb / usbip / stub_tx.c

/*
 * 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 <linux/kthread.h>
#include <linux/socket.h>

#include "usbip_common.h"
#include "stub.h"

static void stub_free_priv_and_urb(struct stub_priv *priv)
{
	struct urb *urb = priv->urb;

	kfree(urb->setup_packet);
	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) {
		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
 *
 * 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.
 *
 */
void stub_complete(struct urb *urb)
{
	struct stub_priv *priv = (struct stub_priv *) urb->context;
	struct stub_device *sdev = priv->sdev;
	unsigned long flags;

	usbip_dbg_stub_tx("complete! status %d\n", urb->status);

	switch (urb->status) {
	case 0:
		/* OK */
		break;
	case -ENOENT:
		dev_info(&urb->dev->dev,
			 "stopped by a call to usb_kill_urb() because of cleaning up a virtual connection\n");
		return;
	case -ECONNRESET:
		dev_info(&urb->dev->dev,
			 "unlinked by a call to usb_unlink_urb()\n");
		break;
	case -EPIPE:
		dev_info(&urb->dev->dev, "endpoint %d is stalled\n",
			 usb_pipeendpoint(urb->pipe));
		break;
	case -ESHUTDOWN:
		dev_info(&urb->dev->dev, "device removed?\n");
		break;
	default:
		dev_info(&urb->dev->dev,
			 "urb completion with non-zero status %d\n",
			 urb->status);
		break;
	}

	/* 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);
}

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;
}

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;
	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;
		struct usbip_iso_packet_descriptor *iso_buffer = NULL;
		struct kvec *iov = NULL;
		int iovnum = 0;

		txsize = 0;
		memset(&pdu_header, 0, sizeof(pdu_header));
		memset(&msg, 0, sizeof(msg));

		if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS)
			iovnum = 2 + urb->number_of_packets;
		else
			iovnum = 2;

		iov = kcalloc(iovnum, sizeof(struct kvec), GFP_KERNEL);

		if (!iov) {
			usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_MALLOC);
			return -1;
		}

		iovnum = 0;

		/* 1. setup usbip_header */
		setup_ret_submit_pdu(&pdu_header, urb);
		usbip_dbg_stub_tx("setup txdata seqnum: %d urb: %p\n",
				  pdu_header.base.seqnum, urb);
		usbip_header_correct_endian(&pdu_header, 1);

		iov[iovnum].iov_base = &pdu_header;
		iov[iovnum].iov_len  = sizeof(pdu_header);
		iovnum++;
		txsize += sizeof(pdu_header);

		/* 2. setup transfer buffer */
		if (usb_pipein(urb->pipe) &&
		    usb_pipetype(urb->pipe) != PIPE_ISOCHRONOUS &&
		    urb->actual_length > 0) {
			iov[iovnum].iov_base = urb->transfer_buffer;
			iov[iovnum].iov_len  = urb->actual_length;
			iovnum++;
			txsize += urb->actual_length;
		} else if (usb_pipein(urb->pipe) &&
			   usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
			/*
			 * For isochronous packets: actual length is the sum of
			 * the actual length of the individual, packets, but as
			 * the packet offsets are not changed there will be
			 * padding between the packets. To optimally use the
			 * bandwidth the padding is not transmitted.
			 */

			int i;

			for (i = 0; i < urb->number_of_packets; i++) {
				iov[iovnum].iov_base = urb->transfer_buffer +
					urb->iso_frame_desc[i].offset;
				iov[iovnum].iov_len =
					urb->iso_frame_desc[i].actual_length;
				iovnum++;
				txsize += urb->iso_frame_desc[i].actual_length;
			}

			if (txsize != sizeof(pdu_header) + urb->actual_length) {
				dev_err(&sdev->interface->dev,
					"actual length of urb %d does not match iso packet sizes %zu\n",
					urb->actual_length,
					txsize-sizeof(pdu_header));
				kfree(iov);
				usbip_event_add(&sdev->ud,
						SDEV_EVENT_ERROR_TCP);
			   return -1;
			}
		}

		/* 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);
				kfree(iov);
				return -1;
			}

			iov[iovnum].iov_base = iso_buffer;
			iov[iovnum].iov_len  = len;
			txsize += len;
			iovnum++;
		}

		ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg,
						iov,  iovnum, txsize);
		if (ret != txsize) {
			dev_err(&sdev->interface->dev,
				"sendmsg failed!, retval %d for %zd\n",
				ret, txsize);
			kfree(iov);
			kfree(iso_buffer);
			usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);
			return -1;
		}

		kfree(iov);
		kfree(iso_buffer);

		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;
}

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));

		usbip_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) {
			dev_err(&sdev->interface->dev,
				"sendmsg failed!, retval %d for %zd\n",
				ret, txsize);
			usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);
			return -1;
		}

		usbip_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;
}

int stub_tx_loop(void *data)
{
	struct usbip_device *ud = data;
	struct stub_device *sdev = container_of(ud, struct stub_device, ud);

	while (!kthread_should_stop()) {
		if (usbip_event_happened(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) ||
					  kthread_should_stop()));
	}

	return 0;
}
Commit	Line	Data
4d7b5c7f TH	1	/*
	2	* Copyright (C) 2003-2008 Takahiro Hirofuchi
	3	*
	4	* This is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation; either version 2 of the License, or
	7	* (at your option) any later version.
	8	*
	9	* This is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write to the Free Software
	16	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
	17	* USA.
	18	*/
	19
9720b4bc	20	#include <linux/kthread.h>
7aaacb43	21	#include <linux/socket.h>
5a0e3ad6	22
4d7b5c7f TH	23	#include "usbip_common.h"
	24	#include "stub.h"
	25
4d7b5c7f TH	26	static void stub_free_priv_and_urb(struct stub_priv *priv)
	27	{
	28	struct urb *urb = priv->urb;
	29
	30	kfree(urb->setup_packet);
	31	kfree(urb->transfer_buffer);
	32	list_del(&priv->list);
	33	kmem_cache_free(stub_priv_cache, priv);
	34	usb_free_urb(urb);
	35	}
	36
	37	/* be in spin_lock_irqsave(&sdev->priv_lock, flags) */
	38	void stub_enqueue_ret_unlink(struct stub_device *sdev, __u32 seqnum,
	39	__u32 status)
	40	{
	41	struct stub_unlink *unlink;
	42
	43	unlink = kzalloc(sizeof(struct stub_unlink), GFP_ATOMIC);
	44	if (!unlink) {
4d7b5c7f TH	45	usbip_event_add(&sdev->ud, VDEV_EVENT_ERROR_MALLOC);
	46	return;
	47	}
	48
	49	unlink->seqnum = seqnum;
	50	unlink->status = status;
	51
	52	list_add_tail(&unlink->list, &sdev->unlink_tx);
	53	}
	54
	55	/**
	56	* stub_complete - completion handler of a usbip urb
	57	* @urb: pointer to the urb completed
4d7b5c7f TH	58	*
	59	* When a urb has completed, the USB core driver calls this function mostly in
	60	* the interrupt context. To return the result of a urb, the completed urb is
	61	* linked to the pending list of returning.
	62	*
	63	*/
	64	void stub_complete(struct urb *urb)
	65	{
	66	struct stub_priv priv = (struct stub_priv ) urb->context;
	67	struct stub_device *sdev = priv->sdev;
	68	unsigned long flags;
	69
b8868e45	70	usbip_dbg_stub_tx("complete! status %d\n", urb->status);
4d7b5c7f	71
4d7b5c7f TH	72	switch (urb->status) {
	73	case 0:
	74	/* OK */
	75	break;
	76	case -ENOENT:
6bb3ee69 CC	77	dev_info(&urb->dev->dev,
6bb3ee69 CC	78	"stopped by a call to usb_kill_urb() because of cleaning up a virtual connection\n");
4d7b5c7f TH	79	return;
4d7b5c7f TH	80	case -ECONNRESET:
6bb3ee69 CC	81	dev_info(&urb->dev->dev,
6bb3ee69 CC	82	"unlinked by a call to usb_unlink_urb()\n");
4d7b5c7f TH	83	break;
4d7b5c7f TH	84	case -EPIPE:
1a4b6f66	85	dev_info(&urb->dev->dev, "endpoint %d is stalled\n",
1a4b6f66	86	usb_pipeendpoint(urb->pipe));
4d7b5c7f TH	87	break;
4d7b5c7f TH	88	case -ESHUTDOWN:
1a4b6f66	89	dev_info(&urb->dev->dev, "device removed?\n");
4d7b5c7f TH	90	break;
4d7b5c7f TH	91	default:
6bb3ee69 CC	92	dev_info(&urb->dev->dev,
	93	"urb completion with non-zero status %d\n",
	94	urb->status);
49aecefc	95	break;
4d7b5c7f TH	96	}
	97
	98	/* link a urb to the queue of tx. */
	99	spin_lock_irqsave(&sdev->priv_lock, flags);
4d7b5c7f TH	100	if (priv->unlinking) {
	101	stub_enqueue_ret_unlink(sdev, priv->seqnum, urb->status);
	102	stub_free_priv_and_urb(priv);
87352760	103	} else {
4d7b5c7f	104	list_move_tail(&priv->list, &sdev->priv_tx);
87352760	105	}
4d7b5c7f TH	106	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	107
	108	/* wake up tx_thread */
	109	wake_up(&sdev->tx_waitq);
	110	}
	111
4d7b5c7f	112	static inline void setup_base_pdu(struct usbip_header_basic *base,
c6956c97	113	__u32 command, __u32 seqnum)
4d7b5c7f	114	{
87352760	115	base->command = command;
	116	base->seqnum = seqnum;
	117	base->devid = 0;
	118	base->ep = 0;
c6956c97	119	base->direction = 0;
4d7b5c7f TH	120	}
	121
	122	static void setup_ret_submit_pdu(struct usbip_header rpdu, struct urb urb)
	123	{
	124	struct stub_priv priv = (struct stub_priv ) urb->context;
	125
	126	setup_base_pdu(&rpdu->base, USBIP_RET_SUBMIT, priv->seqnum);
4d7b5c7f TH	127	usbip_pack_pdu(rpdu, urb, USBIP_RET_SUBMIT, 1);
	128	}
	129
	130	static void setup_ret_unlink_pdu(struct usbip_header *rpdu,
c6956c97	131	struct stub_unlink *unlink)
4d7b5c7f TH	132	{
4d7b5c7f TH	133	setup_base_pdu(&rpdu->base, USBIP_RET_UNLINK, unlink->seqnum);
4d7b5c7f TH	134	rpdu->u.ret_unlink.status = unlink->status;
	135	}
	136
4d7b5c7f TH	137	static struct stub_priv dequeue_from_priv_tx(struct stub_device sdev)
	138	{
	139	unsigned long flags;
	140	struct stub_priv priv, tmp;
	141
	142	spin_lock_irqsave(&sdev->priv_lock, flags);
	143
	144	list_for_each_entry_safe(priv, tmp, &sdev->priv_tx, list) {
	145	list_move_tail(&priv->list, &sdev->priv_free);
	146	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	147	return priv;
	148	}
	149
	150	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	151
	152	return NULL;
	153	}
	154
	155	static int stub_send_ret_submit(struct stub_device *sdev)
	156	{
	157	unsigned long flags;
	158	struct stub_priv priv, tmp;
	159
	160	struct msghdr msg;
4d7b5c7f TH	161	size_t txsize;
	162
	163	size_t total_size = 0;
	164
	165	while ((priv = dequeue_from_priv_tx(sdev)) != NULL) {
	166	int ret;
	167	struct urb *urb = priv->urb;
	168	struct usbip_header pdu_header;
36ac9b05	169	struct usbip_iso_packet_descriptor *iso_buffer = NULL;
28276a28 AM	170	struct kvec *iov = NULL;
28276a28 AM	171	int iovnum = 0;
4d7b5c7f TH	172
	173	txsize = 0;
	174	memset(&pdu_header, 0, sizeof(pdu_header));
	175	memset(&msg, 0, sizeof(msg));
4d7b5c7f	176
28276a28 AM	177	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS)
	178	iovnum = 2 + urb->number_of_packets;
	179	else
	180	iovnum = 2;
4d7b5c7f	181
6baf139e	182	iov = kcalloc(iovnum, sizeof(struct kvec), GFP_KERNEL);
28276a28 AM	183
	184	if (!iov) {
	185	usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_MALLOC);
	186	return -1;
	187	}
	188
	189	iovnum = 0;
4d7b5c7f TH	190
	191	/* 1. setup usbip_header */
	192	setup_ret_submit_pdu(&pdu_header, urb);
28276a28	193	usbip_dbg_stub_tx("setup txdata seqnum: %d urb: %p\n",
c6956c97	194	pdu_header.base.seqnum, urb);
4d7b5c7f TH	195	usbip_header_correct_endian(&pdu_header, 1);
4d7b5c7f TH	196
28276a28 AM	197	iov[iovnum].iov_base = &pdu_header;
	198	iov[iovnum].iov_len = sizeof(pdu_header);
	199	iovnum++;
4d7b5c7f TH	200	txsize += sizeof(pdu_header);
	201
	202	/* 2. setup transfer buffer */
28276a28	203	if (usb_pipein(urb->pipe) &&
c6956c97	204	usb_pipetype(urb->pipe) != PIPE_ISOCHRONOUS &&
c6956c97	205	urb->actual_length > 0) {
28276a28 AM	206	iov[iovnum].iov_base = urb->transfer_buffer;
	207	iov[iovnum].iov_len = urb->actual_length;
	208	iovnum++;
4d7b5c7f	209	txsize += urb->actual_length;
28276a28	210	} else if (usb_pipein(urb->pipe) &&
c6956c97	211	usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
28276a28 AM	212	/*
	213	* For isochronous packets: actual length is the sum of
	214	* the actual length of the individual, packets, but as
	215	* the packet offsets are not changed there will be
	216	* padding between the packets. To optimally use the
	217	* bandwidth the padding is not transmitted.
	218	*/
	219
	220	int i;
3eed8c03	221
28276a28	222	for (i = 0; i < urb->number_of_packets; i++) {
c6956c97	223	iov[iovnum].iov_base = urb->transfer_buffer +
	224	urb->iso_frame_desc[i].offset;
	225	iov[iovnum].iov_len =
	226	urb->iso_frame_desc[i].actual_length;
28276a28 AM	227	iovnum++;
	228	txsize += urb->iso_frame_desc[i].actual_length;
	229	}
	230
	231	if (txsize != sizeof(pdu_header) + urb->actual_length) {
	232	dev_err(&sdev->interface->dev,
6bb3ee69	233	"actual length of urb %d does not match iso packet sizes %zu\n",
c6956c97	234	urb->actual_length,
c6956c97	235	txsize-sizeof(pdu_header));
28276a28	236	kfree(iov);
c6956c97	237	usbip_event_add(&sdev->ud,
c6956c97	238	SDEV_EVENT_ERROR_TCP);
28276a28 AM	239	return -1;
28276a28 AM	240	}
4d7b5c7f TH	241	}
	242
	243	/* 3. setup iso_packet_descriptor */
	244	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
	245	ssize_t len = 0;
	246
	247	iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len);
	248	if (!iso_buffer) {
	249	usbip_event_add(&sdev->ud,
	250	SDEV_EVENT_ERROR_MALLOC);
28276a28	251	kfree(iov);
4d7b5c7f TH	252	return -1;
	253	}
	254
28276a28 AM	255	iov[iovnum].iov_base = iso_buffer;
28276a28 AM	256	iov[iovnum].iov_len = len;
4d7b5c7f	257	txsize += len;
28276a28	258	iovnum++;
4d7b5c7f TH	259	}
4d7b5c7f TH	260
28276a28 AM	261	ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg,
28276a28 AM	262	iov, iovnum, txsize);
4d7b5c7f TH	263	if (ret != txsize) {
	264	dev_err(&sdev->interface->dev,
	265	"sendmsg failed!, retval %d for %zd\n",
	266	ret, txsize);
28276a28	267	kfree(iov);
4d7b5c7f TH	268	kfree(iso_buffer);
	269	usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);
	270	return -1;
	271	}
	272
28276a28	273	kfree(iov);
4d7b5c7f	274	kfree(iso_buffer);
4d7b5c7f TH	275
	276	total_size += txsize;
	277	}
	278
4d7b5c7f	279	spin_lock_irqsave(&sdev->priv_lock, flags);
4d7b5c7f TH	280	list_for_each_entry_safe(priv, tmp, &sdev->priv_free, list) {
	281	stub_free_priv_and_urb(priv);
	282	}
4d7b5c7f TH	283	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	284
	285	return total_size;
	286	}
	287
4d7b5c7f TH	288	static struct stub_unlink dequeue_from_unlink_tx(struct stub_device sdev)
	289	{
	290	unsigned long flags;
	291	struct stub_unlink unlink, tmp;
	292
	293	spin_lock_irqsave(&sdev->priv_lock, flags);
	294
	295	list_for_each_entry_safe(unlink, tmp, &sdev->unlink_tx, list) {
	296	list_move_tail(&unlink->list, &sdev->unlink_free);
	297	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	298	return unlink;
	299	}
	300
	301	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	302
	303	return NULL;
	304	}
	305
4d7b5c7f TH	306	static int stub_send_ret_unlink(struct stub_device *sdev)
	307	{
	308	unsigned long flags;
	309	struct stub_unlink unlink, tmp;
	310
	311	struct msghdr msg;
	312	struct kvec iov[1];
	313	size_t txsize;
	314
	315	size_t total_size = 0;
	316
	317	while ((unlink = dequeue_from_unlink_tx(sdev)) != NULL) {
	318	int ret;
	319	struct usbip_header pdu_header;
	320
	321	txsize = 0;
	322	memset(&pdu_header, 0, sizeof(pdu_header));
	323	memset(&msg, 0, sizeof(msg));
	324	memset(&iov, 0, sizeof(iov));
	325
b8868e45	326	usbip_dbg_stub_tx("setup ret unlink %lu\n", unlink->seqnum);
4d7b5c7f TH	327
	328	/* 1. setup usbip_header */
	329	setup_ret_unlink_pdu(&pdu_header, unlink);
	330	usbip_header_correct_endian(&pdu_header, 1);
	331
	332	iov[0].iov_base = &pdu_header;
	333	iov[0].iov_len = sizeof(pdu_header);
	334	txsize += sizeof(pdu_header);
	335
	336	ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, iov,
	337	1, txsize);
	338	if (ret != txsize) {
	339	dev_err(&sdev->interface->dev,
	340	"sendmsg failed!, retval %d for %zd\n",
	341	ret, txsize);
	342	usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);
	343	return -1;
	344	}
	345
b8868e45	346	usbip_dbg_stub_tx("send txdata\n");
4d7b5c7f TH	347	total_size += txsize;
	348	}
	349
4d7b5c7f TH	350	spin_lock_irqsave(&sdev->priv_lock, flags);
	351
	352	list_for_each_entry_safe(unlink, tmp, &sdev->unlink_free, list) {
	353	list_del(&unlink->list);
	354	kfree(unlink);
	355	}
	356
	357	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	358
	359	return total_size;
	360	}
	361
9720b4bc	362	int stub_tx_loop(void *data)
4d7b5c7f	363	{
9720b4bc	364	struct usbip_device *ud = data;
4d7b5c7f TH	365	struct stub_device *sdev = container_of(ud, struct stub_device, ud);
4d7b5c7f TH	366
9720b4bc	367	while (!kthread_should_stop()) {
b8868e45	368	if (usbip_event_happened(ud))
4d7b5c7f TH	369	break;
	370
	371	/*
	372	* send_ret_submit comes earlier than send_ret_unlink. stub_rx
	373	* looks at only priv_init queue. If the completion of a URB is
	374	* earlier than the receive of CMD_UNLINK, priv is moved to
	375	* priv_tx queue and stub_rx does not find the target priv. In
	376	* this case, vhci_rx receives the result of the submit request
	377	* and then receives the result of the unlink request. The
	378	* result of the submit is given back to the usbcore as the
	379	* completion of the unlink request. The request of the
	380	* unlink is ignored. This is ok because a driver who calls
	381	* usb_unlink_urb() understands the unlink was too late by
	382	* getting the status of the given-backed URB which has the
	383	* status of usb_submit_urb().
	384	*/
	385	if (stub_send_ret_submit(sdev) < 0)
	386	break;
	387
	388	if (stub_send_ret_unlink(sdev) < 0)
	389	break;
	390
	391	wait_event_interruptible(sdev->tx_waitq,
c6956c97	392	(!list_empty(&sdev->priv_tx) \|\|
	393	!list_empty(&sdev->unlink_tx) \|\|
	394	kthread_should_stop()));
4d7b5c7f	395	}
9720b4bc AB	396
9720b4bc AB	397	return 0;
4d7b5c7f	398	}