usbip: vudc: Add vudc_tx
This file contains functions for returning requests to the client.
It also has functions that add requests completed in vudc_rx and
vudc_transfer to the return queue.
This commit is a result of cooperation between Samsung R&D Institute
Poland and Open Operating Systems Student Society at University
of Warsaw (O2S3@UW) consisting of:
Igor Kotrasinski <ikotrasinsk@gmail.com>
Karol Kosik <karo9@interia.eu>
Ewelina Kosmider <3w3lfin@gmail.com>
Dawid Lazarczyk <lazarczyk.dawid@gmail.com>
Piotr Szulc <ps347277@students.mimuw.edu.pl>
Tutor and project owner:
Krzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: Igor Kotrasinski <i.kotrasinsk@samsung.com>
Signed-off-by: Karol Kosik <karo9@interia.eu>
Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/usbip/vudc_tx.c b/drivers/usb/usbip/vudc_tx.c
new file mode 100644
index 0000000..2346617
--- /dev/null
+++ b/drivers/usb/usbip/vudc_tx.c
@@ -0,0 +1,289 @@
+/*
+ * Copyright (C) 2015 Karol Kosik <karo9@interia.eu>
+ * Copyright (C) 2015-2016 Samsung Electronics
+ * Igor Kotrasinski <i.kotrasinsk@samsung.com>
+ *
+ * This program 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 program 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <net/sock.h>
+#include <linux/list.h>
+#include <linux/kthread.h>
+
+#include "usbip_common.h"
+#include "vudc.h"
+
+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 urbp *urb_p)
+{
+ setup_base_pdu(&rpdu->base, USBIP_RET_SUBMIT, urb_p->seqnum);
+ usbip_pack_pdu(rpdu, urb_p->urb, USBIP_RET_SUBMIT, 1);
+}
+
+static void setup_ret_unlink_pdu(struct usbip_header *rpdu,
+ struct v_unlink *unlink)
+{
+ setup_base_pdu(&rpdu->base, USBIP_RET_UNLINK, unlink->seqnum);
+ rpdu->u.ret_unlink.status = unlink->status;
+}
+
+static int v_send_ret_unlink(struct vudc *udc, struct v_unlink *unlink)
+{
+ struct msghdr msg;
+ struct kvec iov[1];
+ size_t txsize;
+
+ 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));
+
+ /* 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(udc->ud.tcp_socket, &msg, iov,
+ 1, txsize);
+ if (ret != txsize) {
+ usbip_event_add(&udc->ud, VUDC_EVENT_ERROR_TCP);
+ if (ret >= 0)
+ return -EPIPE;
+ return ret;
+ }
+ kfree(unlink);
+
+ return txsize;
+}
+
+static int v_send_ret_submit(struct vudc *udc, struct urbp *urb_p)
+{
+ struct urb *urb = urb_p->urb;
+ struct usbip_header pdu_header;
+ struct usbip_iso_packet_descriptor *iso_buffer = NULL;
+ struct kvec *iov = NULL;
+ int iovnum = 0;
+ int ret = 0;
+ size_t txsize;
+ struct msghdr msg;
+
+ txsize = 0;
+ memset(&pdu_header, 0, sizeof(pdu_header));
+ memset(&msg, 0, sizeof(msg));
+
+ if (urb_p->type == USB_ENDPOINT_XFER_ISOC)
+ iovnum = 2 + urb->number_of_packets;
+ else
+ iovnum = 2;
+
+ iov = kcalloc(iovnum, sizeof(*iov), GFP_KERNEL);
+ if (!iov) {
+ usbip_event_add(&udc->ud, VUDC_EVENT_ERROR_MALLOC);
+ ret = -ENOMEM;
+ goto out;
+ }
+ iovnum = 0;
+
+ /* 1. setup usbip_header */
+ setup_ret_submit_pdu(&pdu_header, urb_p);
+ 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 (urb_p->type != USB_ENDPOINT_XFER_ISOC &&
+ usb_pipein(urb->pipe) && 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 (urb_p->type == USB_ENDPOINT_XFER_ISOC &&
+ usb_pipein(urb->pipe)) {
+ /* FIXME - copypasted from stub_tx, refactor */
+ 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) {
+ usbip_event_add(&udc->ud, VUDC_EVENT_ERROR_TCP);
+ ret = -EPIPE;
+ goto out;
+ }
+ }
+ /* else - no buffer to send */
+
+ /* 3. setup iso_packet_descriptor */
+ if (urb_p->type == USB_ENDPOINT_XFER_ISOC) {
+ ssize_t len = 0;
+
+ iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len);
+ if (!iso_buffer) {
+ usbip_event_add(&udc->ud,
+ VUDC_EVENT_ERROR_MALLOC);
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ iov[iovnum].iov_base = iso_buffer;
+ iov[iovnum].iov_len = len;
+ txsize += len;
+ iovnum++;
+ }
+
+ ret = kernel_sendmsg(udc->ud.tcp_socket, &msg,
+ iov, iovnum, txsize);
+ if (ret != txsize) {
+ usbip_event_add(&udc->ud, VUDC_EVENT_ERROR_TCP);
+ if (ret >= 0)
+ ret = -EPIPE;
+ goto out;
+ }
+
+out:
+ kfree(iov);
+ kfree(iso_buffer);
+ free_urbp_and_urb(urb_p);
+ if (ret < 0)
+ return ret;
+ return txsize;
+}
+
+static int v_send_ret(struct vudc *udc)
+{
+ unsigned long flags;
+ struct tx_item *txi;
+ size_t total_size = 0;
+ int ret = 0;
+
+ spin_lock_irqsave(&udc->lock_tx, flags);
+ while (!list_empty(&udc->tx_queue)) {
+ txi = list_first_entry(&udc->tx_queue, struct tx_item,
+ tx_entry);
+ list_del(&txi->tx_entry);
+ spin_unlock_irqrestore(&udc->lock_tx, flags);
+
+ switch (txi->type) {
+ case TX_SUBMIT:
+ ret = v_send_ret_submit(udc, txi->s);
+ break;
+ case TX_UNLINK:
+ ret = v_send_ret_unlink(udc, txi->u);
+ break;
+ }
+ kfree(txi);
+
+ if (ret < 0)
+ return ret;
+
+ total_size += ret;
+
+ spin_lock_irqsave(&udc->lock_tx, flags);
+ }
+
+ spin_unlock_irqrestore(&udc->lock_tx, flags);
+ return total_size;
+}
+
+
+int v_tx_loop(void *data)
+{
+ struct usbip_device *ud = (struct usbip_device *) data;
+ struct vudc *udc = container_of(ud, struct vudc, ud);
+ int ret;
+
+ while (!kthread_should_stop()) {
+ if (usbip_event_happened(&udc->ud))
+ break;
+ ret = v_send_ret(udc);
+ if (ret < 0) {
+ pr_warn("v_tx exit with error %d", ret);
+ break;
+ }
+ wait_event_interruptible(udc->tx_waitq,
+ (!list_empty(&udc->tx_queue) ||
+ kthread_should_stop()));
+ }
+
+ return 0;
+}
+
+/* called with spinlocks held */
+void v_enqueue_ret_unlink(struct vudc *udc, __u32 seqnum, __u32 status)
+{
+ struct tx_item *txi;
+ struct v_unlink *unlink;
+
+ txi = kzalloc(sizeof(*txi), GFP_ATOMIC);
+ if (!txi) {
+ usbip_event_add(&udc->ud, VDEV_EVENT_ERROR_MALLOC);
+ return;
+ }
+ unlink = kzalloc(sizeof(*unlink), GFP_ATOMIC);
+ if (!unlink) {
+ kfree(txi);
+ usbip_event_add(&udc->ud, VDEV_EVENT_ERROR_MALLOC);
+ return;
+ }
+
+ unlink->seqnum = seqnum;
+ unlink->status = status;
+ txi->type = TX_UNLINK;
+ txi->u = unlink;
+
+ list_add_tail(&txi->tx_entry, &udc->tx_queue);
+}
+
+/* called with spinlocks held */
+void v_enqueue_ret_submit(struct vudc *udc, struct urbp *urb_p)
+{
+ struct tx_item *txi;
+
+ txi = kzalloc(sizeof(*txi), GFP_ATOMIC);
+ if (!txi) {
+ usbip_event_add(&udc->ud, VDEV_EVENT_ERROR_MALLOC);
+ return;
+ }
+
+ txi->type = TX_SUBMIT;
+ txi->s = urb_p;
+
+ list_add_tail(&txi->tx_entry, &udc->tx_queue);
+}