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/slab.h> 21 22#include "usbip_common.h" 23#include "stub.h" 24 25 26static 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) */ 38void 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 dev_err(&sdev->interface->dev, "alloc stub_unlink\n"); 46 usbip_event_add(&sdev->ud, VDEV_EVENT_ERROR_MALLOC); 47 return; 48 } 49 50 unlink->seqnum = seqnum; 51 unlink->status = status; 52 53 list_add_tail(&unlink->list, &sdev->unlink_tx); 54} 55 56/** 57 * stub_complete - completion handler of a usbip urb 58 * @urb: pointer to the urb completed 59 * 60 * When a urb has completed, the USB core driver calls this function mostly in 61 * the interrupt context. To return the result of a urb, the completed urb is 62 * linked to the pending list of returning. 63 * 64 */ 65void stub_complete(struct urb *urb) 66{ 67 struct stub_priv *priv = (struct stub_priv *) urb->context; 68 struct stub_device *sdev = priv->sdev; 69 unsigned long flags; 70 71 usbip_dbg_stub_tx("complete! status %d\n", urb->status); 72 73 74 switch (urb->status) { 75 case 0: 76 /* OK */ 77 break; 78 case -ENOENT: 79 usbip_uinfo("stopped by a call of usb_kill_urb() because of" 80 "cleaning up a virtual connection\n"); 81 return; 82 case -ECONNRESET: 83 usbip_uinfo("unlinked by a call of usb_unlink_urb()\n"); 84 break; 85 case -EPIPE: 86 usbip_uinfo("endpoint %d is stalled\n", 87 usb_pipeendpoint(urb->pipe)); 88 break; 89 case -ESHUTDOWN: 90 usbip_uinfo("device removed?\n"); 91 break; 92 default: 93 usbip_uinfo("urb completion with non-zero status %d\n", 94 urb->status); 95 } 96 97 /* link a urb to the queue of tx. */ 98 spin_lock_irqsave(&sdev->priv_lock, flags); 99 100 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); 105 106 107 spin_unlock_irqrestore(&sdev->priv_lock, flags); 108 109 /* wake up tx_thread */ 110 wake_up(&sdev->tx_waitq); 111} 112 113 114/*-------------------------------------------------------------------------*/ 115/* fill PDU */ 116 117static inline void setup_base_pdu(struct usbip_header_basic *base, 118 __u32 command, __u32 seqnum) 119{ 120 base->command = command; 121 base->seqnum = seqnum; 122 base->devid = 0; 123 base->ep = 0; 124 base->direction = 0; 125} 126 127static void setup_ret_submit_pdu(struct usbip_header *rpdu, struct urb *urb) 128{ 129 struct stub_priv *priv = (struct stub_priv *) urb->context; 130 131 setup_base_pdu(&rpdu->base, USBIP_RET_SUBMIT, priv->seqnum); 132 133 usbip_pack_pdu(rpdu, urb, USBIP_RET_SUBMIT, 1); 134} 135 136static void setup_ret_unlink_pdu(struct usbip_header *rpdu, 137 struct stub_unlink *unlink) 138{ 139 setup_base_pdu(&rpdu->base, USBIP_RET_UNLINK, unlink->seqnum); 140 141 rpdu->u.ret_unlink.status = unlink->status; 142} 143 144 145/*-------------------------------------------------------------------------*/ 146/* send RET_SUBMIT */ 147 148static struct stub_priv *dequeue_from_priv_tx(struct stub_device *sdev) 149{ 150 unsigned long flags; 151 struct stub_priv *priv, *tmp; 152 153 spin_lock_irqsave(&sdev->priv_lock, flags); 154 155 list_for_each_entry_safe(priv, tmp, &sdev->priv_tx, list) { 156 list_move_tail(&priv->list, &sdev->priv_free); 157 spin_unlock_irqrestore(&sdev->priv_lock, flags); 158 return priv; 159 } 160 161 spin_unlock_irqrestore(&sdev->priv_lock, flags); 162 163 return NULL; 164} 165 166static int stub_send_ret_submit(struct stub_device *sdev) 167{ 168 unsigned long flags; 169 struct stub_priv *priv, *tmp; 170 171 struct msghdr msg; 172 struct kvec iov[3]; 173 size_t txsize; 174 175 size_t total_size = 0; 176 177 while ((priv = dequeue_from_priv_tx(sdev)) != NULL) { 178 int ret; 179 struct urb *urb = priv->urb; 180 struct usbip_header pdu_header; 181 void *iso_buffer = NULL; 182 183 txsize = 0; 184 memset(&pdu_header, 0, sizeof(pdu_header)); 185 memset(&msg, 0, sizeof(msg)); 186 memset(&iov, 0, sizeof(iov)); 187 188 usbip_dbg_stub_tx("setup txdata urb %p\n", urb); 189 190 191 /* 1. setup usbip_header */ 192 setup_ret_submit_pdu(&pdu_header, urb); 193 usbip_header_correct_endian(&pdu_header, 1); 194 195 iov[0].iov_base = &pdu_header; 196 iov[0].iov_len = sizeof(pdu_header); 197 txsize += sizeof(pdu_header); 198 199 /* 2. setup transfer buffer */ 200 if (usb_pipein(urb->pipe) && urb->actual_length > 0) { 201 iov[1].iov_base = urb->transfer_buffer; 202 iov[1].iov_len = urb->actual_length; 203 txsize += urb->actual_length; 204 } 205 206 /* 3. setup iso_packet_descriptor */ 207 if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) { 208 ssize_t len = 0; 209 210 iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len); 211 if (!iso_buffer) { 212 usbip_event_add(&sdev->ud, 213 SDEV_EVENT_ERROR_MALLOC); 214 return -1; 215 } 216 217 iov[2].iov_base = iso_buffer; 218 iov[2].iov_len = len; 219 txsize += len; 220 } 221 222 ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, iov, 223 3, txsize); 224 if (ret != txsize) { 225 dev_err(&sdev->interface->dev, 226 "sendmsg failed!, retval %d for %zd\n", 227 ret, txsize); 228 kfree(iso_buffer); 229 usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP); 230 return -1; 231 } 232 233 kfree(iso_buffer); 234 usbip_dbg_stub_tx("send txdata\n"); 235 236 total_size += txsize; 237 } 238 239 240 spin_lock_irqsave(&sdev->priv_lock, flags); 241 242 list_for_each_entry_safe(priv, tmp, &sdev->priv_free, list) { 243 stub_free_priv_and_urb(priv); 244 } 245 246 spin_unlock_irqrestore(&sdev->priv_lock, flags); 247 248 return total_size; 249} 250 251 252/*-------------------------------------------------------------------------*/ 253/* send RET_UNLINK */ 254 255static struct stub_unlink *dequeue_from_unlink_tx(struct stub_device *sdev) 256{ 257 unsigned long flags; 258 struct stub_unlink *unlink, *tmp; 259 260 spin_lock_irqsave(&sdev->priv_lock, flags); 261 262 list_for_each_entry_safe(unlink, tmp, &sdev->unlink_tx, list) { 263 list_move_tail(&unlink->list, &sdev->unlink_free); 264 spin_unlock_irqrestore(&sdev->priv_lock, flags); 265 return unlink; 266 } 267 268 spin_unlock_irqrestore(&sdev->priv_lock, flags); 269 270 return NULL; 271} 272 273 274static int stub_send_ret_unlink(struct stub_device *sdev) 275{ 276 unsigned long flags; 277 struct stub_unlink *unlink, *tmp; 278 279 struct msghdr msg; 280 struct kvec iov[1]; 281 size_t txsize; 282 283 size_t total_size = 0; 284 285 while ((unlink = dequeue_from_unlink_tx(sdev)) != NULL) { 286 int ret; 287 struct usbip_header pdu_header; 288 289 txsize = 0; 290 memset(&pdu_header, 0, sizeof(pdu_header)); 291 memset(&msg, 0, sizeof(msg)); 292 memset(&iov, 0, sizeof(iov)); 293 294 usbip_dbg_stub_tx("setup ret unlink %lu\n", unlink->seqnum); 295 296 /* 1. setup usbip_header */ 297 setup_ret_unlink_pdu(&pdu_header, unlink); 298 usbip_header_correct_endian(&pdu_header, 1); 299 300 iov[0].iov_base = &pdu_header; 301 iov[0].iov_len = sizeof(pdu_header); 302 txsize += sizeof(pdu_header); 303 304 ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, iov, 305 1, txsize); 306 if (ret != txsize) { 307 dev_err(&sdev->interface->dev, 308 "sendmsg failed!, retval %d for %zd\n", 309 ret, txsize); 310 usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP); 311 return -1; 312 } 313 314 315 usbip_dbg_stub_tx("send txdata\n"); 316 317 total_size += txsize; 318 } 319 320 321 spin_lock_irqsave(&sdev->priv_lock, flags); 322 323 list_for_each_entry_safe(unlink, tmp, &sdev->unlink_free, list) { 324 list_del(&unlink->list); 325 kfree(unlink); 326 } 327 328 spin_unlock_irqrestore(&sdev->priv_lock, flags); 329 330 return total_size; 331} 332 333 334/*-------------------------------------------------------------------------*/ 335 336void stub_tx_loop(struct usbip_task *ut) 337{ 338 struct usbip_device *ud = container_of(ut, struct usbip_device, tcp_tx); 339 struct stub_device *sdev = container_of(ud, struct stub_device, ud); 340 341 while (1) { 342 if (signal_pending(current)) { 343 usbip_dbg_stub_tx("signal catched\n"); 344 break; 345 } 346 347 if (usbip_event_happened(ud)) 348 break; 349 350 /* 351 * send_ret_submit comes earlier than send_ret_unlink. stub_rx 352 * looks at only priv_init queue. If the completion of a URB is 353 * earlier than the receive of CMD_UNLINK, priv is moved to 354 * priv_tx queue and stub_rx does not find the target priv. In 355 * this case, vhci_rx receives the result of the submit request 356 * and then receives the result of the unlink request. The 357 * result of the submit is given back to the usbcore as the 358 * completion of the unlink request. The request of the 359 * unlink is ignored. This is ok because a driver who calls 360 * usb_unlink_urb() understands the unlink was too late by 361 * getting the status of the given-backed URB which has the 362 * status of usb_submit_urb(). 363 */ 364 if (stub_send_ret_submit(sdev) < 0) 365 break; 366 367 if (stub_send_ret_unlink(sdev) < 0) 368 break; 369 370 wait_event_interruptible(sdev->tx_waitq, 371 (!list_empty(&sdev->priv_tx) || 372 !list_empty(&sdev->unlink_tx))); 373 } 374} 375