[deliverable/linux.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 (sdev->ud.tcp_socket == NULL) {
		usbip_dbg_stub_tx("ignore urb for closed connection %p", urb);
		/* It will be freed in stub_device_cleanup_urbs(). */
	} else 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->udev->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->udev->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->udev->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);
6dc38da4 NI	100	if (sdev->ud.tcp_socket == NULL) {
	101	usbip_dbg_stub_tx("ignore urb for closed connection %p", urb);
	102	/* It will be freed in stub_device_cleanup_urbs(). */
	103	} else if (priv->unlinking) {
4d7b5c7f TH	104	stub_enqueue_ret_unlink(sdev, priv->seqnum, urb->status);
4d7b5c7f TH	105	stub_free_priv_and_urb(priv);
87352760	106	} else {
4d7b5c7f	107	list_move_tail(&priv->list, &sdev->priv_tx);
87352760	108	}
4d7b5c7f TH	109	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	110
	111	/* wake up tx_thread */
	112	wake_up(&sdev->tx_waitq);
	113	}
	114
4d7b5c7f	115	static inline void setup_base_pdu(struct usbip_header_basic *base,
c6956c97	116	__u32 command, __u32 seqnum)
4d7b5c7f	117	{
87352760	118	base->command = command;
	119	base->seqnum = seqnum;
	120	base->devid = 0;
	121	base->ep = 0;
c6956c97	122	base->direction = 0;
4d7b5c7f TH	123	}
	124
	125	static void setup_ret_submit_pdu(struct usbip_header rpdu, struct urb urb)
	126	{
	127	struct stub_priv priv = (struct stub_priv ) urb->context;
	128
	129	setup_base_pdu(&rpdu->base, USBIP_RET_SUBMIT, priv->seqnum);
4d7b5c7f TH	130	usbip_pack_pdu(rpdu, urb, USBIP_RET_SUBMIT, 1);
	131	}
	132
	133	static void setup_ret_unlink_pdu(struct usbip_header *rpdu,
c6956c97	134	struct stub_unlink *unlink)
4d7b5c7f TH	135	{
4d7b5c7f TH	136	setup_base_pdu(&rpdu->base, USBIP_RET_UNLINK, unlink->seqnum);
4d7b5c7f TH	137	rpdu->u.ret_unlink.status = unlink->status;
	138	}
	139
4d7b5c7f TH	140	static struct stub_priv dequeue_from_priv_tx(struct stub_device sdev)
	141	{
	142	unsigned long flags;
	143	struct stub_priv priv, tmp;
	144
	145	spin_lock_irqsave(&sdev->priv_lock, flags);
	146
	147	list_for_each_entry_safe(priv, tmp, &sdev->priv_tx, list) {
	148	list_move_tail(&priv->list, &sdev->priv_free);
	149	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	150	return priv;
	151	}
	152
	153	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	154
	155	return NULL;
	156	}
	157
	158	static int stub_send_ret_submit(struct stub_device *sdev)
	159	{
	160	unsigned long flags;
	161	struct stub_priv priv, tmp;
	162
	163	struct msghdr msg;
4d7b5c7f TH	164	size_t txsize;
	165
	166	size_t total_size = 0;
	167
	168	while ((priv = dequeue_from_priv_tx(sdev)) != NULL) {
	169	int ret;
	170	struct urb *urb = priv->urb;
	171	struct usbip_header pdu_header;
36ac9b05	172	struct usbip_iso_packet_descriptor *iso_buffer = NULL;
28276a28 AM	173	struct kvec *iov = NULL;
28276a28 AM	174	int iovnum = 0;
4d7b5c7f TH	175
	176	txsize = 0;
	177	memset(&pdu_header, 0, sizeof(pdu_header));
	178	memset(&msg, 0, sizeof(msg));
4d7b5c7f	179
28276a28 AM	180	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS)
	181	iovnum = 2 + urb->number_of_packets;
	182	else
	183	iovnum = 2;
4d7b5c7f	184
6baf139e	185	iov = kcalloc(iovnum, sizeof(struct kvec), GFP_KERNEL);
28276a28 AM	186
	187	if (!iov) {
	188	usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_MALLOC);
	189	return -1;
	190	}
	191
	192	iovnum = 0;
4d7b5c7f TH	193
	194	/* 1. setup usbip_header */
	195	setup_ret_submit_pdu(&pdu_header, urb);
28276a28	196	usbip_dbg_stub_tx("setup txdata seqnum: %d urb: %p\n",
c6956c97	197	pdu_header.base.seqnum, urb);
4d7b5c7f TH	198	usbip_header_correct_endian(&pdu_header, 1);
4d7b5c7f TH	199
28276a28 AM	200	iov[iovnum].iov_base = &pdu_header;
	201	iov[iovnum].iov_len = sizeof(pdu_header);
	202	iovnum++;
4d7b5c7f TH	203	txsize += sizeof(pdu_header);
	204
	205	/* 2. setup transfer buffer */
28276a28	206	if (usb_pipein(urb->pipe) &&
c6956c97	207	usb_pipetype(urb->pipe) != PIPE_ISOCHRONOUS &&
c6956c97	208	urb->actual_length > 0) {
28276a28 AM	209	iov[iovnum].iov_base = urb->transfer_buffer;
	210	iov[iovnum].iov_len = urb->actual_length;
	211	iovnum++;
4d7b5c7f	212	txsize += urb->actual_length;
28276a28	213	} else if (usb_pipein(urb->pipe) &&
c6956c97	214	usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
28276a28 AM	215	/*
	216	* For isochronous packets: actual length is the sum of
	217	* the actual length of the individual, packets, but as
	218	* the packet offsets are not changed there will be
	219	* padding between the packets. To optimally use the
	220	* bandwidth the padding is not transmitted.
	221	*/
	222
	223	int i;
3eed8c03	224
28276a28	225	for (i = 0; i < urb->number_of_packets; i++) {
c6956c97	226	iov[iovnum].iov_base = urb->transfer_buffer +
	227	urb->iso_frame_desc[i].offset;
	228	iov[iovnum].iov_len =
	229	urb->iso_frame_desc[i].actual_length;
28276a28 AM	230	iovnum++;
	231	txsize += urb->iso_frame_desc[i].actual_length;
	232	}
	233
	234	if (txsize != sizeof(pdu_header) + urb->actual_length) {
8c7003a3	235	dev_err(&sdev->udev->dev,
6bb3ee69	236	"actual length of urb %d does not match iso packet sizes %zu\n",
c6956c97	237	urb->actual_length,
c6956c97	238	txsize-sizeof(pdu_header));
28276a28	239	kfree(iov);
c6956c97	240	usbip_event_add(&sdev->ud,
c6956c97	241	SDEV_EVENT_ERROR_TCP);
28276a28 AM	242	return -1;
28276a28 AM	243	}
4d7b5c7f TH	244	}
	245
	246	/* 3. setup iso_packet_descriptor */
	247	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
	248	ssize_t len = 0;
	249
	250	iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len);
	251	if (!iso_buffer) {
	252	usbip_event_add(&sdev->ud,
	253	SDEV_EVENT_ERROR_MALLOC);
28276a28	254	kfree(iov);
4d7b5c7f TH	255	return -1;
	256	}
	257
28276a28 AM	258	iov[iovnum].iov_base = iso_buffer;
28276a28 AM	259	iov[iovnum].iov_len = len;
4d7b5c7f	260	txsize += len;
28276a28	261	iovnum++;
4d7b5c7f TH	262	}
4d7b5c7f TH	263
28276a28 AM	264	ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg,
28276a28 AM	265	iov, iovnum, txsize);
4d7b5c7f	266	if (ret != txsize) {
8c7003a3	267	dev_err(&sdev->udev->dev,
4d7b5c7f TH	268	"sendmsg failed!, retval %d for %zd\n",
4d7b5c7f TH	269	ret, txsize);
28276a28	270	kfree(iov);
4d7b5c7f TH	271	kfree(iso_buffer);
	272	usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);
	273	return -1;
	274	}
	275
28276a28	276	kfree(iov);
4d7b5c7f	277	kfree(iso_buffer);
4d7b5c7f TH	278
	279	total_size += txsize;
	280	}
	281
4d7b5c7f	282	spin_lock_irqsave(&sdev->priv_lock, flags);
4d7b5c7f TH	283	list_for_each_entry_safe(priv, tmp, &sdev->priv_free, list) {
	284	stub_free_priv_and_urb(priv);
	285	}
4d7b5c7f TH	286	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	287
	288	return total_size;
	289	}
	290
4d7b5c7f TH	291	static struct stub_unlink dequeue_from_unlink_tx(struct stub_device sdev)
	292	{
	293	unsigned long flags;
	294	struct stub_unlink unlink, tmp;
	295
	296	spin_lock_irqsave(&sdev->priv_lock, flags);
	297
	298	list_for_each_entry_safe(unlink, tmp, &sdev->unlink_tx, list) {
	299	list_move_tail(&unlink->list, &sdev->unlink_free);
	300	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	301	return unlink;
	302	}
	303
	304	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	305
	306	return NULL;
	307	}
	308
4d7b5c7f TH	309	static int stub_send_ret_unlink(struct stub_device *sdev)
	310	{
	311	unsigned long flags;
	312	struct stub_unlink unlink, tmp;
	313
	314	struct msghdr msg;
	315	struct kvec iov[1];
	316	size_t txsize;
	317
	318	size_t total_size = 0;
	319
	320	while ((unlink = dequeue_from_unlink_tx(sdev)) != NULL) {
	321	int ret;
	322	struct usbip_header pdu_header;
	323
	324	txsize = 0;
	325	memset(&pdu_header, 0, sizeof(pdu_header));
	326	memset(&msg, 0, sizeof(msg));
	327	memset(&iov, 0, sizeof(iov));
	328
b8868e45	329	usbip_dbg_stub_tx("setup ret unlink %lu\n", unlink->seqnum);
4d7b5c7f TH	330
	331	/* 1. setup usbip_header */
	332	setup_ret_unlink_pdu(&pdu_header, unlink);
	333	usbip_header_correct_endian(&pdu_header, 1);
	334
	335	iov[0].iov_base = &pdu_header;
	336	iov[0].iov_len = sizeof(pdu_header);
	337	txsize += sizeof(pdu_header);
	338
	339	ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, iov,
	340	1, txsize);
	341	if (ret != txsize) {
8c7003a3	342	dev_err(&sdev->udev->dev,
4d7b5c7f TH	343	"sendmsg failed!, retval %d for %zd\n",
	344	ret, txsize);
	345	usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP);
	346	return -1;
	347	}
	348
b8868e45	349	usbip_dbg_stub_tx("send txdata\n");
4d7b5c7f TH	350	total_size += txsize;
	351	}
	352
4d7b5c7f TH	353	spin_lock_irqsave(&sdev->priv_lock, flags);
	354
	355	list_for_each_entry_safe(unlink, tmp, &sdev->unlink_free, list) {
	356	list_del(&unlink->list);
	357	kfree(unlink);
	358	}
	359
	360	spin_unlock_irqrestore(&sdev->priv_lock, flags);
	361
	362	return total_size;
	363	}
	364
9720b4bc	365	int stub_tx_loop(void *data)
4d7b5c7f	366	{
9720b4bc	367	struct usbip_device *ud = data;
4d7b5c7f TH	368	struct stub_device *sdev = container_of(ud, struct stub_device, ud);
4d7b5c7f TH	369
9720b4bc	370	while (!kthread_should_stop()) {
b8868e45	371	if (usbip_event_happened(ud))
4d7b5c7f TH	372	break;
	373
	374	/*
	375	* send_ret_submit comes earlier than send_ret_unlink. stub_rx
	376	* looks at only priv_init queue. If the completion of a URB is
	377	* earlier than the receive of CMD_UNLINK, priv is moved to
	378	* priv_tx queue and stub_rx does not find the target priv. In
	379	* this case, vhci_rx receives the result of the submit request
	380	* and then receives the result of the unlink request. The
	381	* result of the submit is given back to the usbcore as the
	382	* completion of the unlink request. The request of the
	383	* unlink is ignored. This is ok because a driver who calls
	384	* usb_unlink_urb() understands the unlink was too late by
	385	* getting the status of the given-backed URB which has the
	386	* status of usb_submit_urb().
	387	*/
	388	if (stub_send_ret_submit(sdev) < 0)
	389	break;
	390
	391	if (stub_send_ret_unlink(sdev) < 0)
	392	break;
	393
	394	wait_event_interruptible(sdev->tx_waitq,
c6956c97	395	(!list_empty(&sdev->priv_tx) \|\|
	396	!list_empty(&sdev->unlink_tx) \|\|
	397	kthread_should_stop()));
4d7b5c7f	398	}
9720b4bc AB	399
9720b4bc AB	400	return 0;
4d7b5c7f	401	}