linux/drivers/usb/usbip/vudc_tx.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2015 Karol Kosik <karo9@interia.eu>
   4 * Copyright (C) 2015-2016 Samsung Electronics
   5 *               Igor Kotrasinski <i.kotrasinsk@samsung.com>
   6 */
   7
   8#include <net/sock.h>
   9#include <linux/list.h>
  10#include <linux/kthread.h>
  11
  12#include "usbip_common.h"
  13#include "vudc.h"
  14
  15static inline void setup_base_pdu(struct usbip_header_basic *base,
  16                                  __u32 command, __u32 seqnum)
  17{
  18        base->command   = command;
  19        base->seqnum    = seqnum;
  20        base->devid     = 0;
  21        base->ep        = 0;
  22        base->direction = 0;
  23}
  24
  25static void setup_ret_submit_pdu(struct usbip_header *rpdu, struct urbp *urb_p)
  26{
  27        setup_base_pdu(&rpdu->base, USBIP_RET_SUBMIT, urb_p->seqnum);
  28        usbip_pack_pdu(rpdu, urb_p->urb, USBIP_RET_SUBMIT, 1);
  29}
  30
  31static void setup_ret_unlink_pdu(struct usbip_header *rpdu,
  32                                 struct v_unlink *unlink)
  33{
  34        setup_base_pdu(&rpdu->base, USBIP_RET_UNLINK, unlink->seqnum);
  35        rpdu->u.ret_unlink.status = unlink->status;
  36}
  37
  38static int v_send_ret_unlink(struct vudc *udc, struct v_unlink *unlink)
  39{
  40        struct msghdr msg;
  41        struct kvec iov[1];
  42        size_t txsize;
  43
  44        int ret;
  45        struct usbip_header pdu_header;
  46
  47        txsize = 0;
  48        memset(&pdu_header, 0, sizeof(pdu_header));
  49        memset(&msg, 0, sizeof(msg));
  50        memset(&iov, 0, sizeof(iov));
  51
  52        /* 1. setup usbip_header */
  53        setup_ret_unlink_pdu(&pdu_header, unlink);
  54        usbip_header_correct_endian(&pdu_header, 1);
  55
  56        iov[0].iov_base = &pdu_header;
  57        iov[0].iov_len  = sizeof(pdu_header);
  58        txsize += sizeof(pdu_header);
  59
  60        ret = kernel_sendmsg(udc->ud.tcp_socket, &msg, iov,
  61                             1, txsize);
  62        if (ret != txsize) {
  63                usbip_event_add(&udc->ud, VUDC_EVENT_ERROR_TCP);
  64                if (ret >= 0)
  65                        return -EPIPE;
  66                return ret;
  67        }
  68        kfree(unlink);
  69
  70        return txsize;
  71}
  72
  73static int v_send_ret_submit(struct vudc *udc, struct urbp *urb_p)
  74{
  75        struct urb *urb = urb_p->urb;
  76        struct usbip_header pdu_header;
  77        struct usbip_iso_packet_descriptor *iso_buffer = NULL;
  78        struct kvec *iov = NULL;
  79        int iovnum = 0;
  80        int ret = 0;
  81        size_t txsize;
  82        struct msghdr msg;
  83
  84        txsize = 0;
  85        memset(&pdu_header, 0, sizeof(pdu_header));
  86        memset(&msg, 0, sizeof(msg));
  87
  88        if (urb->actual_length > 0 && !urb->transfer_buffer) {
  89                dev_err(&udc->gadget.dev,
  90                        "urb: actual_length %d transfer_buffer null\n",
  91                        urb->actual_length);
  92                return -1;
  93        }
  94
  95        if (urb_p->type == USB_ENDPOINT_XFER_ISOC)
  96                iovnum = 2 + urb->number_of_packets;
  97        else
  98                iovnum = 2;
  99
 100        iov = kcalloc(iovnum, sizeof(*iov), GFP_KERNEL);
 101        if (!iov) {
 102                usbip_event_add(&udc->ud, VUDC_EVENT_ERROR_MALLOC);
 103                ret = -ENOMEM;
 104                goto out;
 105        }
 106        iovnum = 0;
 107
 108        /* 1. setup usbip_header */
 109        setup_ret_submit_pdu(&pdu_header, urb_p);
 110        usbip_dbg_stub_tx("setup txdata seqnum: %d\n",
 111                          pdu_header.base.seqnum);
 112        usbip_header_correct_endian(&pdu_header, 1);
 113
 114        iov[iovnum].iov_base = &pdu_header;
 115        iov[iovnum].iov_len  = sizeof(pdu_header);
 116        iovnum++;
 117        txsize += sizeof(pdu_header);
 118
 119        /* 2. setup transfer buffer */
 120        if (urb_p->type != USB_ENDPOINT_XFER_ISOC &&
 121            usb_pipein(urb->pipe) && urb->actual_length > 0) {
 122                iov[iovnum].iov_base = urb->transfer_buffer;
 123                iov[iovnum].iov_len  = urb->actual_length;
 124                iovnum++;
 125                txsize += urb->actual_length;
 126        } else if (urb_p->type == USB_ENDPOINT_XFER_ISOC &&
 127                usb_pipein(urb->pipe)) {
 128                /* FIXME - copypasted from stub_tx, refactor */
 129                int i;
 130
 131                for (i = 0; i < urb->number_of_packets; i++) {
 132                        iov[iovnum].iov_base = urb->transfer_buffer +
 133                                urb->iso_frame_desc[i].offset;
 134                        iov[iovnum].iov_len =
 135                                urb->iso_frame_desc[i].actual_length;
 136                        iovnum++;
 137                        txsize += urb->iso_frame_desc[i].actual_length;
 138                }
 139
 140                if (txsize != sizeof(pdu_header) + urb->actual_length) {
 141                        usbip_event_add(&udc->ud, VUDC_EVENT_ERROR_TCP);
 142                        ret = -EPIPE;
 143                        goto out;
 144                }
 145        }
 146        /* else - no buffer to send */
 147
 148        /* 3. setup iso_packet_descriptor */
 149        if (urb_p->type == USB_ENDPOINT_XFER_ISOC) {
 150                ssize_t len = 0;
 151
 152                iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len);
 153                if (!iso_buffer) {
 154                        usbip_event_add(&udc->ud,
 155                                        VUDC_EVENT_ERROR_MALLOC);
 156                        ret = -ENOMEM;
 157                        goto out;
 158                }
 159
 160                iov[iovnum].iov_base = iso_buffer;
 161                iov[iovnum].iov_len  = len;
 162                txsize += len;
 163                iovnum++;
 164        }
 165
 166        ret = kernel_sendmsg(udc->ud.tcp_socket, &msg,
 167                                                iov,  iovnum, txsize);
 168        if (ret != txsize) {
 169                usbip_event_add(&udc->ud, VUDC_EVENT_ERROR_TCP);
 170                if (ret >= 0)
 171                        ret = -EPIPE;
 172                goto out;
 173        }
 174
 175out:
 176        kfree(iov);
 177        kfree(iso_buffer);
 178        free_urbp_and_urb(urb_p);
 179        if (ret < 0)
 180                return ret;
 181        return txsize;
 182}
 183
 184static int v_send_ret(struct vudc *udc)
 185{
 186        unsigned long flags;
 187        struct tx_item *txi;
 188        size_t total_size = 0;
 189        int ret = 0;
 190
 191        spin_lock_irqsave(&udc->lock_tx, flags);
 192        while (!list_empty(&udc->tx_queue)) {
 193                txi = list_first_entry(&udc->tx_queue, struct tx_item,
 194                                       tx_entry);
 195                list_del(&txi->tx_entry);
 196                spin_unlock_irqrestore(&udc->lock_tx, flags);
 197
 198                switch (txi->type) {
 199                case TX_SUBMIT:
 200                        ret = v_send_ret_submit(udc, txi->s);
 201                        break;
 202                case TX_UNLINK:
 203                        ret = v_send_ret_unlink(udc, txi->u);
 204                        break;
 205                }
 206                kfree(txi);
 207
 208                if (ret < 0)
 209                        return ret;
 210
 211                total_size += ret;
 212
 213                spin_lock_irqsave(&udc->lock_tx, flags);
 214        }
 215
 216        spin_unlock_irqrestore(&udc->lock_tx, flags);
 217        return total_size;
 218}
 219
 220
 221int v_tx_loop(void *data)
 222{
 223        struct usbip_device *ud = (struct usbip_device *) data;
 224        struct vudc *udc = container_of(ud, struct vudc, ud);
 225        int ret;
 226
 227        while (!kthread_should_stop()) {
 228                if (usbip_event_happened(&udc->ud))
 229                        break;
 230                ret = v_send_ret(udc);
 231                if (ret < 0) {
 232                        pr_warn("v_tx exit with error %d", ret);
 233                        break;
 234                }
 235                wait_event_interruptible(udc->tx_waitq,
 236                                         (!list_empty(&udc->tx_queue) ||
 237                                         kthread_should_stop()));
 238        }
 239
 240        return 0;
 241}
 242
 243/* called with spinlocks held */
 244void v_enqueue_ret_unlink(struct vudc *udc, __u32 seqnum, __u32 status)
 245{
 246        struct tx_item *txi;
 247        struct v_unlink *unlink;
 248
 249        txi = kzalloc(sizeof(*txi), GFP_ATOMIC);
 250        if (!txi) {
 251                usbip_event_add(&udc->ud, VDEV_EVENT_ERROR_MALLOC);
 252                return;
 253        }
 254        unlink = kzalloc(sizeof(*unlink), GFP_ATOMIC);
 255        if (!unlink) {
 256                kfree(txi);
 257                usbip_event_add(&udc->ud, VDEV_EVENT_ERROR_MALLOC);
 258                return;
 259        }
 260
 261        unlink->seqnum = seqnum;
 262        unlink->status = status;
 263        txi->type = TX_UNLINK;
 264        txi->u = unlink;
 265
 266        list_add_tail(&txi->tx_entry, &udc->tx_queue);
 267}
 268
 269/* called with spinlocks held */
 270void v_enqueue_ret_submit(struct vudc *udc, struct urbp *urb_p)
 271{
 272        struct tx_item *txi;
 273
 274        txi = kzalloc(sizeof(*txi), GFP_ATOMIC);
 275        if (!txi) {
 276                usbip_event_add(&udc->ud, VDEV_EVENT_ERROR_MALLOC);
 277                return;
 278        }
 279
 280        txi->type = TX_SUBMIT;
 281        txi->s = urb_p;
 282
 283        list_add_tail(&txi->tx_entry, &udc->tx_queue);
 284}
 285