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 (priv->unlinking) { 101 stub_enqueue_ret_unlink(sdev, priv->seqnum, urb->status); 102 stub_free_priv_and_urb(priv); 103 } else { 104 list_move_tail(&priv->list, &sdev->priv_tx); 105 } 106 spin_unlock_irqrestore(&sdev->priv_lock, flags); 107 108 /* wake up tx_thread */ 109 wake_up(&sdev->tx_waitq); 110 } 111 112 static inline void setup_base_pdu(struct usbip_header_basic *base, 113 __u32 command, __u32 seqnum) 114 { 115 base->command = command; 116 base->seqnum = seqnum; 117 base->devid = 0; 118 base->ep = 0; 119 base->direction = 0; 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); 127 usbip_pack_pdu(rpdu, urb, USBIP_RET_SUBMIT, 1); 128 } 129 130 static void setup_ret_unlink_pdu(struct usbip_header *rpdu, 131 struct stub_unlink *unlink) 132 { 133 setup_base_pdu(&rpdu->base, USBIP_RET_UNLINK, unlink->seqnum); 134 rpdu->u.ret_unlink.status = unlink->status; 135 } 136 137 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; 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; 169 struct usbip_iso_packet_descriptor *iso_buffer = NULL; 170 struct kvec *iov = NULL; 171 int iovnum = 0; 172 173 txsize = 0; 174 memset(&pdu_header, 0, sizeof(pdu_header)); 175 memset(&msg, 0, sizeof(msg)); 176 177 if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) 178 iovnum = 2 + urb->number_of_packets; 179 else 180 iovnum = 2; 181 182 iov = kcalloc(iovnum, sizeof(struct kvec), GFP_KERNEL); 183 184 if (!iov) { 185 usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_MALLOC); 186 return -1; 187 } 188 189 iovnum = 0; 190 191 /* 1. setup usbip_header */ 192 setup_ret_submit_pdu(&pdu_header, urb); 193 usbip_dbg_stub_tx("setup txdata seqnum: %d urb: %p\n", 194 pdu_header.base.seqnum, urb); 195 usbip_header_correct_endian(&pdu_header, 1); 196 197 iov[iovnum].iov_base = &pdu_header; 198 iov[iovnum].iov_len = sizeof(pdu_header); 199 iovnum++; 200 txsize += sizeof(pdu_header); 201 202 /* 2. setup transfer buffer */ 203 if (usb_pipein(urb->pipe) && 204 usb_pipetype(urb->pipe) != PIPE_ISOCHRONOUS && 205 urb->actual_length > 0) { 206 iov[iovnum].iov_base = urb->transfer_buffer; 207 iov[iovnum].iov_len = urb->actual_length; 208 iovnum++; 209 txsize += urb->actual_length; 210 } else if (usb_pipein(urb->pipe) && 211 usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) { 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; 221 222 for (i = 0; i < urb->number_of_packets; i++) { 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; 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, 233 "actual length of urb %d does not match iso packet sizes %zu\n", 234 urb->actual_length, 235 txsize-sizeof(pdu_header)); 236 kfree(iov); 237 usbip_event_add(&sdev->ud, 238 SDEV_EVENT_ERROR_TCP); 239 return -1; 240 } 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); 251 kfree(iov); 252 return -1; 253 } 254 255 iov[iovnum].iov_base = iso_buffer; 256 iov[iovnum].iov_len = len; 257 txsize += len; 258 iovnum++; 259 } 260 261 ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, 262 iov, iovnum, txsize); 263 if (ret != txsize) { 264 dev_err(&sdev->interface->dev, 265 "sendmsg failed!, retval %d for %zd\n", 266 ret, txsize); 267 kfree(iov); 268 kfree(iso_buffer); 269 usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP); 270 return -1; 271 } 272 273 kfree(iov); 274 kfree(iso_buffer); 275 276 total_size += txsize; 277 } 278 279 spin_lock_irqsave(&sdev->priv_lock, flags); 280 list_for_each_entry_safe(priv, tmp, &sdev->priv_free, list) { 281 stub_free_priv_and_urb(priv); 282 } 283 spin_unlock_irqrestore(&sdev->priv_lock, flags); 284 285 return total_size; 286 } 287 288 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 } 305 306 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)); 325 326 usbip_dbg_stub_tx("setup ret unlink %lu\n", unlink->seqnum); 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 } 345 346 usbip_dbg_stub_tx("send txdata\n"); 347 total_size += txsize; 348 } 349 350 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 } 361 362 int stub_tx_loop(void *data) 363 { 364 struct usbip_device *ud = data; 365 struct stub_device *sdev = container_of(ud, struct stub_device, ud); 366 367 while (!kthread_should_stop()) { 368 if (usbip_event_happened(ud)) 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, 392 (!list_empty(&sdev->priv_tx) || 393 !list_empty(&sdev->unlink_tx) || 394 kthread_should_stop())); 395 } 396 397 return 0; 398 } 399