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 20 #include <linux/kthread.h> 21 #include <linux/socket.h> 22 23 #include "usbip_common.h" 24 #include "stub.h" 25 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) { 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 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 70 usbip_dbg_stub_tx("complete! status %d\n", urb->status); 71 72 switch (urb->status) { 73 case 0: 74 /* OK */ 75 break; 76 case -ENOENT: 77 dev_info(&urb->dev->dev, 78 "stopped by a call to usb_kill_urb() because of cleaning up a virtual connection\n"); 79 return; 80 case -ECONNRESET: 81 dev_info(&urb->dev->dev, 82 "unlinked by a call to usb_unlink_urb()\n"); 83 break; 84 case -EPIPE: 85 dev_info(&urb->dev->dev, "endpoint %d is stalled\n", 86 usb_pipeendpoint(urb->pipe)); 87 break; 88 case -ESHUTDOWN: 89 dev_info(&urb->dev->dev, "device removed?\n"); 90 break; 91 default: 92 dev_info(&urb->dev->dev, 93 "urb completion with non-zero status %d\n", 94 urb->status); 95 break; 96 } 97 98 /* link a urb to the queue of tx. */ 99 spin_lock_irqsave(&sdev->priv_lock, flags); 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) { 104 stub_enqueue_ret_unlink(sdev, priv->seqnum, urb->status); 105 stub_free_priv_and_urb(priv); 106 } else { 107 list_move_tail(&priv->list, &sdev->priv_tx); 108 } 109 spin_unlock_irqrestore(&sdev->priv_lock, flags); 110 111 /* wake up tx_thread */ 112 wake_up(&sdev->tx_waitq); 113 } 114 115 static inline void setup_base_pdu(struct usbip_header_basic *base, 116 __u32 command, __u32 seqnum) 117 { 118 base->command = command; 119 base->seqnum = seqnum; 120 base->devid = 0; 121 base->ep = 0; 122 base->direction = 0; 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); 130 usbip_pack_pdu(rpdu, urb, USBIP_RET_SUBMIT, 1); 131 } 132 133 static void setup_ret_unlink_pdu(struct usbip_header *rpdu, 134 struct stub_unlink *unlink) 135 { 136 setup_base_pdu(&rpdu->base, USBIP_RET_UNLINK, unlink->seqnum); 137 rpdu->u.ret_unlink.status = unlink->status; 138 } 139 140 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; 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; 172 struct usbip_iso_packet_descriptor *iso_buffer = NULL; 173 struct kvec *iov = NULL; 174 int iovnum = 0; 175 176 txsize = 0; 177 memset(&pdu_header, 0, sizeof(pdu_header)); 178 memset(&msg, 0, sizeof(msg)); 179 180 if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) 181 iovnum = 2 + urb->number_of_packets; 182 else 183 iovnum = 2; 184 185 iov = kcalloc(iovnum, sizeof(struct kvec), GFP_KERNEL); 186 187 if (!iov) { 188 usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_MALLOC); 189 return -1; 190 } 191 192 iovnum = 0; 193 194 /* 1. setup usbip_header */ 195 setup_ret_submit_pdu(&pdu_header, urb); 196 usbip_dbg_stub_tx("setup txdata seqnum: %d urb: %p\n", 197 pdu_header.base.seqnum, urb); 198 usbip_header_correct_endian(&pdu_header, 1); 199 200 iov[iovnum].iov_base = &pdu_header; 201 iov[iovnum].iov_len = sizeof(pdu_header); 202 iovnum++; 203 txsize += sizeof(pdu_header); 204 205 /* 2. setup transfer buffer */ 206 if (usb_pipein(urb->pipe) && 207 usb_pipetype(urb->pipe) != PIPE_ISOCHRONOUS && 208 urb->actual_length > 0) { 209 iov[iovnum].iov_base = urb->transfer_buffer; 210 iov[iovnum].iov_len = urb->actual_length; 211 iovnum++; 212 txsize += urb->actual_length; 213 } else if (usb_pipein(urb->pipe) && 214 usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) { 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; 224 225 for (i = 0; i < urb->number_of_packets; i++) { 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; 230 iovnum++; 231 txsize += urb->iso_frame_desc[i].actual_length; 232 } 233 234 if (txsize != sizeof(pdu_header) + urb->actual_length) { 235 dev_err(&sdev->udev->dev, 236 "actual length of urb %d does not match iso packet sizes %zu\n", 237 urb->actual_length, 238 txsize-sizeof(pdu_header)); 239 kfree(iov); 240 usbip_event_add(&sdev->ud, 241 SDEV_EVENT_ERROR_TCP); 242 return -1; 243 } 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); 254 kfree(iov); 255 return -1; 256 } 257 258 iov[iovnum].iov_base = iso_buffer; 259 iov[iovnum].iov_len = len; 260 txsize += len; 261 iovnum++; 262 } 263 264 ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, 265 iov, iovnum, txsize); 266 if (ret != txsize) { 267 dev_err(&sdev->udev->dev, 268 "sendmsg failed!, retval %d for %zd\n", 269 ret, txsize); 270 kfree(iov); 271 kfree(iso_buffer); 272 usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP); 273 return -1; 274 } 275 276 kfree(iov); 277 kfree(iso_buffer); 278 279 total_size += txsize; 280 } 281 282 spin_lock_irqsave(&sdev->priv_lock, flags); 283 list_for_each_entry_safe(priv, tmp, &sdev->priv_free, list) { 284 stub_free_priv_and_urb(priv); 285 } 286 spin_unlock_irqrestore(&sdev->priv_lock, flags); 287 288 return total_size; 289 } 290 291 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 } 308 309 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)); 328 329 usbip_dbg_stub_tx("setup ret unlink %lu\n", unlink->seqnum); 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) { 342 dev_err(&sdev->udev->dev, 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 } 348 349 usbip_dbg_stub_tx("send txdata\n"); 350 total_size += txsize; 351 } 352 353 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 } 364 365 int stub_tx_loop(void *data) 366 { 367 struct usbip_device *ud = data; 368 struct stub_device *sdev = container_of(ud, struct stub_device, ud); 369 370 while (!kthread_should_stop()) { 371 if (usbip_event_happened(ud)) 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, 395 (!list_empty(&sdev->priv_tx) || 396 !list_empty(&sdev->unlink_tx) || 397 kthread_should_stop())); 398 } 399 400 return 0; 401 } 402