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 * Krzysztof Opasiak <k.opasiak@samsung.com> 7 */ 8 9 #include <linux/device.h> 10 #include <linux/list.h> 11 #include <linux/usb/gadget.h> 12 #include <linux/usb/ch9.h> 13 #include <linux/sysfs.h> 14 #include <linux/kthread.h> 15 #include <linux/byteorder/generic.h> 16 17 #include "usbip_common.h" 18 #include "vudc.h" 19 20 #include <net/sock.h> 21 22 /* called with udc->lock held */ 23 int get_gadget_descs(struct vudc *udc) 24 { 25 struct vrequest *usb_req; 26 struct vep *ep0 = to_vep(udc->gadget.ep0); 27 struct usb_device_descriptor *ddesc = &udc->dev_desc; 28 struct usb_ctrlrequest req; 29 int ret; 30 31 if (!udc->driver || !udc->pullup) 32 return -EINVAL; 33 34 req.bRequestType = USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE; 35 req.bRequest = USB_REQ_GET_DESCRIPTOR; 36 req.wValue = cpu_to_le16(USB_DT_DEVICE << 8); 37 req.wIndex = cpu_to_le16(0); 38 req.wLength = cpu_to_le16(sizeof(*ddesc)); 39 40 spin_unlock(&udc->lock); 41 ret = udc->driver->setup(&(udc->gadget), &req); 42 spin_lock(&udc->lock); 43 if (ret < 0) 44 goto out; 45 46 /* assuming request queue is empty; request is now on top */ 47 usb_req = list_last_entry(&ep0->req_queue, struct vrequest, req_entry); 48 list_del(&usb_req->req_entry); 49 50 if (usb_req->req.length > sizeof(*ddesc)) { 51 ret = -EOVERFLOW; 52 goto giveback_req; 53 } 54 55 memcpy(ddesc, usb_req->req.buf, sizeof(*ddesc)); 56 udc->desc_cached = 1; 57 ret = 0; 58 giveback_req: 59 usb_req->req.status = 0; 60 usb_req->req.actual = usb_req->req.length; 61 usb_gadget_giveback_request(&(ep0->ep), &(usb_req->req)); 62 out: 63 return ret; 64 } 65 66 /* 67 * Exposes device descriptor from the gadget driver. 68 */ 69 static ssize_t dev_desc_read(struct file *file, struct kobject *kobj, 70 struct bin_attribute *attr, char *out, 71 loff_t off, size_t count) 72 { 73 struct device *dev = kobj_to_dev(kobj); 74 struct vudc *udc = (struct vudc *)dev_get_drvdata(dev); 75 char *desc_ptr = (char *) &udc->dev_desc; 76 unsigned long flags; 77 int ret; 78 79 spin_lock_irqsave(&udc->lock, flags); 80 if (!udc->desc_cached) { 81 ret = -ENODEV; 82 goto unlock; 83 } 84 85 memcpy(out, desc_ptr + off, count); 86 ret = count; 87 unlock: 88 spin_unlock_irqrestore(&udc->lock, flags); 89 return ret; 90 } 91 static BIN_ATTR_RO(dev_desc, sizeof(struct usb_device_descriptor)); 92 93 static ssize_t usbip_sockfd_store(struct device *dev, 94 struct device_attribute *attr, 95 const char *in, size_t count) 96 { 97 struct vudc *udc = (struct vudc *) dev_get_drvdata(dev); 98 int rv; 99 int sockfd = 0; 100 int err; 101 struct socket *socket; 102 unsigned long flags; 103 int ret; 104 struct task_struct *tcp_rx = NULL; 105 struct task_struct *tcp_tx = NULL; 106 107 rv = kstrtoint(in, 0, &sockfd); 108 if (rv != 0) 109 return -EINVAL; 110 111 if (!udc) { 112 dev_err(dev, "no device"); 113 return -ENODEV; 114 } 115 spin_lock_irqsave(&udc->lock, flags); 116 /* Don't export what we don't have */ 117 if (!udc->driver || !udc->pullup) { 118 dev_err(dev, "gadget not bound"); 119 ret = -ENODEV; 120 goto unlock; 121 } 122 123 if (sockfd != -1) { 124 if (udc->connected) { 125 dev_err(dev, "Device already connected"); 126 ret = -EBUSY; 127 goto unlock; 128 } 129 130 spin_lock_irq(&udc->ud.lock); 131 132 if (udc->ud.status != SDEV_ST_AVAILABLE) { 133 ret = -EINVAL; 134 goto unlock_ud; 135 } 136 137 socket = sockfd_lookup(sockfd, &err); 138 if (!socket) { 139 dev_err(dev, "failed to lookup sock"); 140 ret = -EINVAL; 141 goto unlock_ud; 142 } 143 144 if (socket->type != SOCK_STREAM) { 145 dev_err(dev, "Expecting SOCK_STREAM - found %d", 146 socket->type); 147 ret = -EINVAL; 148 goto sock_err; 149 } 150 151 /* unlock and create threads and get tasks */ 152 spin_unlock_irq(&udc->ud.lock); 153 spin_unlock_irqrestore(&udc->lock, flags); 154 155 tcp_rx = kthread_create(&v_rx_loop, &udc->ud, "vudc_rx"); 156 if (IS_ERR(tcp_rx)) { 157 sockfd_put(socket); 158 return -EINVAL; 159 } 160 tcp_tx = kthread_create(&v_tx_loop, &udc->ud, "vudc_tx"); 161 if (IS_ERR(tcp_tx)) { 162 kthread_stop(tcp_rx); 163 sockfd_put(socket); 164 return -EINVAL; 165 } 166 167 /* get task structs now */ 168 get_task_struct(tcp_rx); 169 get_task_struct(tcp_tx); 170 171 /* lock and update udc->ud state */ 172 spin_lock_irqsave(&udc->lock, flags); 173 spin_lock_irq(&udc->ud.lock); 174 175 udc->ud.tcp_socket = socket; 176 udc->ud.tcp_rx = tcp_rx; 177 udc->ud.tcp_rx = tcp_tx; 178 udc->ud.status = SDEV_ST_USED; 179 180 spin_unlock_irq(&udc->ud.lock); 181 182 ktime_get_ts64(&udc->start_time); 183 v_start_timer(udc); 184 udc->connected = 1; 185 186 spin_unlock_irqrestore(&udc->lock, flags); 187 188 wake_up_process(udc->ud.tcp_rx); 189 wake_up_process(udc->ud.tcp_tx); 190 return count; 191 192 } else { 193 if (!udc->connected) { 194 dev_err(dev, "Device not connected"); 195 ret = -EINVAL; 196 goto unlock; 197 } 198 199 spin_lock_irq(&udc->ud.lock); 200 if (udc->ud.status != SDEV_ST_USED) { 201 ret = -EINVAL; 202 goto unlock_ud; 203 } 204 spin_unlock_irq(&udc->ud.lock); 205 206 usbip_event_add(&udc->ud, VUDC_EVENT_DOWN); 207 } 208 209 spin_unlock_irqrestore(&udc->lock, flags); 210 211 return count; 212 213 sock_err: 214 sockfd_put(socket); 215 unlock_ud: 216 spin_unlock_irq(&udc->ud.lock); 217 unlock: 218 spin_unlock_irqrestore(&udc->lock, flags); 219 220 return ret; 221 } 222 static DEVICE_ATTR_WO(usbip_sockfd); 223 224 static ssize_t usbip_status_show(struct device *dev, 225 struct device_attribute *attr, char *out) 226 { 227 struct vudc *udc = (struct vudc *) dev_get_drvdata(dev); 228 int status; 229 230 if (!udc) { 231 dev_err(dev, "no device"); 232 return -ENODEV; 233 } 234 spin_lock_irq(&udc->ud.lock); 235 status = udc->ud.status; 236 spin_unlock_irq(&udc->ud.lock); 237 238 return snprintf(out, PAGE_SIZE, "%d\n", status); 239 } 240 static DEVICE_ATTR_RO(usbip_status); 241 242 static struct attribute *dev_attrs[] = { 243 &dev_attr_usbip_sockfd.attr, 244 &dev_attr_usbip_status.attr, 245 NULL, 246 }; 247 248 static struct bin_attribute *dev_bin_attrs[] = { 249 &bin_attr_dev_desc, 250 NULL, 251 }; 252 253 static const struct attribute_group vudc_attr_group = { 254 .attrs = dev_attrs, 255 .bin_attrs = dev_bin_attrs, 256 }; 257 258 const struct attribute_group *vudc_groups[] = { 259 &vudc_attr_group, 260 NULL, 261 }; 262