]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation | |
3 | * Copyright (C) 2009, 2010, 2011 Red Hat, Inc. | |
4 | * Copyright (C) 2009, 2010, 2011 Amit Shah <amit.shah@redhat.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
19 | */ | |
20 | #include <linux/cdev.h> | |
21 | #include <linux/debugfs.h> | |
22 | #include <linux/completion.h> | |
23 | #include <linux/device.h> | |
24 | #include <linux/err.h> | |
25 | #include <linux/freezer.h> | |
26 | #include <linux/fs.h> | |
27 | #include <linux/init.h> | |
28 | #include <linux/list.h> | |
29 | #include <linux/poll.h> | |
30 | #include <linux/sched.h> | |
31 | #include <linux/slab.h> | |
32 | #include <linux/spinlock.h> | |
33 | #include <linux/virtio.h> | |
34 | #include <linux/virtio_console.h> | |
35 | #include <linux/wait.h> | |
36 | #include <linux/workqueue.h> | |
37 | #include <linux/module.h> | |
38 | #include "../tty/hvc/hvc_console.h" | |
39 | ||
40 | /* | |
41 | * This is a global struct for storing common data for all the devices | |
42 | * this driver handles. | |
43 | * | |
44 | * Mainly, it has a linked list for all the consoles in one place so | |
45 | * that callbacks from hvc for get_chars(), put_chars() work properly | |
46 | * across multiple devices and multiple ports per device. | |
47 | */ | |
48 | struct ports_driver_data { | |
49 | /* Used for registering chardevs */ | |
50 | struct class *class; | |
51 | ||
52 | /* Used for exporting per-port information to debugfs */ | |
53 | struct dentry *debugfs_dir; | |
54 | ||
55 | /* List of all the devices we're handling */ | |
56 | struct list_head portdevs; | |
57 | ||
58 | /* Number of devices this driver is handling */ | |
59 | unsigned int index; | |
60 | ||
61 | /* | |
62 | * This is used to keep track of the number of hvc consoles | |
63 | * spawned by this driver. This number is given as the first | |
64 | * argument to hvc_alloc(). To correctly map an initial | |
65 | * console spawned via hvc_instantiate to the console being | |
66 | * hooked up via hvc_alloc, we need to pass the same vtermno. | |
67 | * | |
68 | * We also just assume the first console being initialised was | |
69 | * the first one that got used as the initial console. | |
70 | */ | |
71 | unsigned int next_vtermno; | |
72 | ||
73 | /* All the console devices handled by this driver */ | |
74 | struct list_head consoles; | |
75 | }; | |
76 | static struct ports_driver_data pdrvdata; | |
77 | ||
78 | DEFINE_SPINLOCK(pdrvdata_lock); | |
79 | DECLARE_COMPLETION(early_console_added); | |
80 | ||
81 | /* This struct holds information that's relevant only for console ports */ | |
82 | struct console { | |
83 | /* We'll place all consoles in a list in the pdrvdata struct */ | |
84 | struct list_head list; | |
85 | ||
86 | /* The hvc device associated with this console port */ | |
87 | struct hvc_struct *hvc; | |
88 | ||
89 | /* The size of the console */ | |
90 | struct winsize ws; | |
91 | ||
92 | /* | |
93 | * This number identifies the number that we used to register | |
94 | * with hvc in hvc_instantiate() and hvc_alloc(); this is the | |
95 | * number passed on by the hvc callbacks to us to | |
96 | * differentiate between the other console ports handled by | |
97 | * this driver | |
98 | */ | |
99 | u32 vtermno; | |
100 | }; | |
101 | ||
102 | struct port_buffer { | |
103 | char *buf; | |
104 | ||
105 | /* size of the buffer in *buf above */ | |
106 | size_t size; | |
107 | ||
108 | /* used length of the buffer */ | |
109 | size_t len; | |
110 | /* offset in the buf from which to consume data */ | |
111 | size_t offset; | |
112 | }; | |
113 | ||
114 | /* | |
115 | * This is a per-device struct that stores data common to all the | |
116 | * ports for that device (vdev->priv). | |
117 | */ | |
118 | struct ports_device { | |
119 | /* Next portdev in the list, head is in the pdrvdata struct */ | |
120 | struct list_head list; | |
121 | ||
122 | /* | |
123 | * Workqueue handlers where we process deferred work after | |
124 | * notification | |
125 | */ | |
126 | struct work_struct control_work; | |
127 | ||
128 | struct list_head ports; | |
129 | ||
130 | /* To protect the list of ports */ | |
131 | spinlock_t ports_lock; | |
132 | ||
133 | /* To protect the vq operations for the control channel */ | |
134 | spinlock_t cvq_lock; | |
135 | ||
136 | /* The current config space is stored here */ | |
137 | struct virtio_console_config config; | |
138 | ||
139 | /* The virtio device we're associated with */ | |
140 | struct virtio_device *vdev; | |
141 | ||
142 | /* | |
143 | * A couple of virtqueues for the control channel: one for | |
144 | * guest->host transfers, one for host->guest transfers | |
145 | */ | |
146 | struct virtqueue *c_ivq, *c_ovq; | |
147 | ||
148 | /* Array of per-port IO virtqueues */ | |
149 | struct virtqueue **in_vqs, **out_vqs; | |
150 | ||
151 | /* Used for numbering devices for sysfs and debugfs */ | |
152 | unsigned int drv_index; | |
153 | ||
154 | /* Major number for this device. Ports will be created as minors. */ | |
155 | int chr_major; | |
156 | }; | |
157 | ||
158 | struct port_stats { | |
159 | unsigned long bytes_sent, bytes_received, bytes_discarded; | |
160 | }; | |
161 | ||
162 | /* This struct holds the per-port data */ | |
163 | struct port { | |
164 | /* Next port in the list, head is in the ports_device */ | |
165 | struct list_head list; | |
166 | ||
167 | /* Pointer to the parent virtio_console device */ | |
168 | struct ports_device *portdev; | |
169 | ||
170 | /* The current buffer from which data has to be fed to readers */ | |
171 | struct port_buffer *inbuf; | |
172 | ||
173 | /* | |
174 | * To protect the operations on the in_vq associated with this | |
175 | * port. Has to be a spinlock because it can be called from | |
176 | * interrupt context (get_char()). | |
177 | */ | |
178 | spinlock_t inbuf_lock; | |
179 | ||
180 | /* Protect the operations on the out_vq. */ | |
181 | spinlock_t outvq_lock; | |
182 | ||
183 | /* The IO vqs for this port */ | |
184 | struct virtqueue *in_vq, *out_vq; | |
185 | ||
186 | /* File in the debugfs directory that exposes this port's information */ | |
187 | struct dentry *debugfs_file; | |
188 | ||
189 | /* | |
190 | * Keep count of the bytes sent, received and discarded for | |
191 | * this port for accounting and debugging purposes. These | |
192 | * counts are not reset across port open / close events. | |
193 | */ | |
194 | struct port_stats stats; | |
195 | ||
196 | /* | |
197 | * The entries in this struct will be valid if this port is | |
198 | * hooked up to an hvc console | |
199 | */ | |
200 | struct console cons; | |
201 | ||
202 | /* Each port associates with a separate char device */ | |
203 | struct cdev *cdev; | |
204 | struct device *dev; | |
205 | ||
206 | /* Reference-counting to handle port hot-unplugs and file operations */ | |
207 | struct kref kref; | |
208 | ||
209 | /* A waitqueue for poll() or blocking read operations */ | |
210 | wait_queue_head_t waitqueue; | |
211 | ||
212 | /* The 'name' of the port that we expose via sysfs properties */ | |
213 | char *name; | |
214 | ||
215 | /* We can notify apps of host connect / disconnect events via SIGIO */ | |
216 | struct fasync_struct *async_queue; | |
217 | ||
218 | /* The 'id' to identify the port with the Host */ | |
219 | u32 id; | |
220 | ||
221 | bool outvq_full; | |
222 | ||
223 | /* Is the host device open */ | |
224 | bool host_connected; | |
225 | ||
226 | /* We should allow only one process to open a port */ | |
227 | bool guest_connected; | |
228 | }; | |
229 | ||
230 | /* This is the very early arch-specified put chars function. */ | |
231 | static int (*early_put_chars)(u32, const char *, int); | |
232 | ||
233 | static struct port *find_port_by_vtermno(u32 vtermno) | |
234 | { | |
235 | struct port *port; | |
236 | struct console *cons; | |
237 | unsigned long flags; | |
238 | ||
239 | spin_lock_irqsave(&pdrvdata_lock, flags); | |
240 | list_for_each_entry(cons, &pdrvdata.consoles, list) { | |
241 | if (cons->vtermno == vtermno) { | |
242 | port = container_of(cons, struct port, cons); | |
243 | goto out; | |
244 | } | |
245 | } | |
246 | port = NULL; | |
247 | out: | |
248 | spin_unlock_irqrestore(&pdrvdata_lock, flags); | |
249 | return port; | |
250 | } | |
251 | ||
252 | static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev, | |
253 | dev_t dev) | |
254 | { | |
255 | struct port *port; | |
256 | unsigned long flags; | |
257 | ||
258 | spin_lock_irqsave(&portdev->ports_lock, flags); | |
259 | list_for_each_entry(port, &portdev->ports, list) | |
260 | if (port->cdev->dev == dev) | |
261 | goto out; | |
262 | port = NULL; | |
263 | out: | |
264 | spin_unlock_irqrestore(&portdev->ports_lock, flags); | |
265 | ||
266 | return port; | |
267 | } | |
268 | ||
269 | static struct port *find_port_by_devt(dev_t dev) | |
270 | { | |
271 | struct ports_device *portdev; | |
272 | struct port *port; | |
273 | unsigned long flags; | |
274 | ||
275 | spin_lock_irqsave(&pdrvdata_lock, flags); | |
276 | list_for_each_entry(portdev, &pdrvdata.portdevs, list) { | |
277 | port = find_port_by_devt_in_portdev(portdev, dev); | |
278 | if (port) | |
279 | goto out; | |
280 | } | |
281 | port = NULL; | |
282 | out: | |
283 | spin_unlock_irqrestore(&pdrvdata_lock, flags); | |
284 | return port; | |
285 | } | |
286 | ||
287 | static struct port *find_port_by_id(struct ports_device *portdev, u32 id) | |
288 | { | |
289 | struct port *port; | |
290 | unsigned long flags; | |
291 | ||
292 | spin_lock_irqsave(&portdev->ports_lock, flags); | |
293 | list_for_each_entry(port, &portdev->ports, list) | |
294 | if (port->id == id) | |
295 | goto out; | |
296 | port = NULL; | |
297 | out: | |
298 | spin_unlock_irqrestore(&portdev->ports_lock, flags); | |
299 | ||
300 | return port; | |
301 | } | |
302 | ||
303 | static struct port *find_port_by_vq(struct ports_device *portdev, | |
304 | struct virtqueue *vq) | |
305 | { | |
306 | struct port *port; | |
307 | unsigned long flags; | |
308 | ||
309 | spin_lock_irqsave(&portdev->ports_lock, flags); | |
310 | list_for_each_entry(port, &portdev->ports, list) | |
311 | if (port->in_vq == vq || port->out_vq == vq) | |
312 | goto out; | |
313 | port = NULL; | |
314 | out: | |
315 | spin_unlock_irqrestore(&portdev->ports_lock, flags); | |
316 | return port; | |
317 | } | |
318 | ||
319 | static bool is_console_port(struct port *port) | |
320 | { | |
321 | if (port->cons.hvc) | |
322 | return true; | |
323 | return false; | |
324 | } | |
325 | ||
326 | static inline bool use_multiport(struct ports_device *portdev) | |
327 | { | |
328 | /* | |
329 | * This condition can be true when put_chars is called from | |
330 | * early_init | |
331 | */ | |
332 | if (!portdev->vdev) | |
333 | return 0; | |
334 | return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT); | |
335 | } | |
336 | ||
337 | static void free_buf(struct port_buffer *buf) | |
338 | { | |
339 | kfree(buf->buf); | |
340 | kfree(buf); | |
341 | } | |
342 | ||
343 | static struct port_buffer *alloc_buf(size_t buf_size) | |
344 | { | |
345 | struct port_buffer *buf; | |
346 | ||
347 | buf = kmalloc(sizeof(*buf), GFP_KERNEL); | |
348 | if (!buf) | |
349 | goto fail; | |
350 | buf->buf = kzalloc(buf_size, GFP_KERNEL); | |
351 | if (!buf->buf) | |
352 | goto free_buf; | |
353 | buf->len = 0; | |
354 | buf->offset = 0; | |
355 | buf->size = buf_size; | |
356 | return buf; | |
357 | ||
358 | free_buf: | |
359 | kfree(buf); | |
360 | fail: | |
361 | return NULL; | |
362 | } | |
363 | ||
364 | /* Callers should take appropriate locks */ | |
365 | static struct port_buffer *get_inbuf(struct port *port) | |
366 | { | |
367 | struct port_buffer *buf; | |
368 | unsigned int len; | |
369 | ||
370 | if (port->inbuf) | |
371 | return port->inbuf; | |
372 | ||
373 | buf = virtqueue_get_buf(port->in_vq, &len); | |
374 | if (buf) { | |
375 | buf->len = len; | |
376 | buf->offset = 0; | |
377 | port->stats.bytes_received += len; | |
378 | } | |
379 | return buf; | |
380 | } | |
381 | ||
382 | /* | |
383 | * Create a scatter-gather list representing our input buffer and put | |
384 | * it in the queue. | |
385 | * | |
386 | * Callers should take appropriate locks. | |
387 | */ | |
388 | static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf) | |
389 | { | |
390 | struct scatterlist sg[1]; | |
391 | int ret; | |
392 | ||
393 | sg_init_one(sg, buf->buf, buf->size); | |
394 | ||
395 | ret = virtqueue_add_buf(vq, sg, 0, 1, buf); | |
396 | virtqueue_kick(vq); | |
397 | return ret; | |
398 | } | |
399 | ||
400 | /* Discard any unread data this port has. Callers lockers. */ | |
401 | static void discard_port_data(struct port *port) | |
402 | { | |
403 | struct port_buffer *buf; | |
404 | unsigned int err; | |
405 | ||
406 | if (!port->portdev) { | |
407 | /* Device has been unplugged. vqs are already gone. */ | |
408 | return; | |
409 | } | |
410 | buf = get_inbuf(port); | |
411 | ||
412 | err = 0; | |
413 | while (buf) { | |
414 | port->stats.bytes_discarded += buf->len - buf->offset; | |
415 | if (add_inbuf(port->in_vq, buf) < 0) { | |
416 | err++; | |
417 | free_buf(buf); | |
418 | } | |
419 | port->inbuf = NULL; | |
420 | buf = get_inbuf(port); | |
421 | } | |
422 | if (err) | |
423 | dev_warn(port->dev, "Errors adding %d buffers back to vq\n", | |
424 | err); | |
425 | } | |
426 | ||
427 | static bool port_has_data(struct port *port) | |
428 | { | |
429 | unsigned long flags; | |
430 | bool ret; | |
431 | ||
432 | ret = false; | |
433 | spin_lock_irqsave(&port->inbuf_lock, flags); | |
434 | port->inbuf = get_inbuf(port); | |
435 | if (port->inbuf) | |
436 | ret = true; | |
437 | ||
438 | spin_unlock_irqrestore(&port->inbuf_lock, flags); | |
439 | return ret; | |
440 | } | |
441 | ||
442 | static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id, | |
443 | unsigned int event, unsigned int value) | |
444 | { | |
445 | struct scatterlist sg[1]; | |
446 | struct virtio_console_control cpkt; | |
447 | struct virtqueue *vq; | |
448 | unsigned int len; | |
449 | ||
450 | if (!use_multiport(portdev)) | |
451 | return 0; | |
452 | ||
453 | cpkt.id = port_id; | |
454 | cpkt.event = event; | |
455 | cpkt.value = value; | |
456 | ||
457 | vq = portdev->c_ovq; | |
458 | ||
459 | sg_init_one(sg, &cpkt, sizeof(cpkt)); | |
460 | if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt) >= 0) { | |
461 | virtqueue_kick(vq); | |
462 | while (!virtqueue_get_buf(vq, &len)) | |
463 | cpu_relax(); | |
464 | } | |
465 | return 0; | |
466 | } | |
467 | ||
468 | static ssize_t send_control_msg(struct port *port, unsigned int event, | |
469 | unsigned int value) | |
470 | { | |
471 | /* Did the port get unplugged before userspace closed it? */ | |
472 | if (port->portdev) | |
473 | return __send_control_msg(port->portdev, port->id, event, value); | |
474 | return 0; | |
475 | } | |
476 | ||
477 | /* Callers must take the port->outvq_lock */ | |
478 | static void reclaim_consumed_buffers(struct port *port) | |
479 | { | |
480 | void *buf; | |
481 | unsigned int len; | |
482 | ||
483 | if (!port->portdev) { | |
484 | /* Device has been unplugged. vqs are already gone. */ | |
485 | return; | |
486 | } | |
487 | while ((buf = virtqueue_get_buf(port->out_vq, &len))) { | |
488 | kfree(buf); | |
489 | port->outvq_full = false; | |
490 | } | |
491 | } | |
492 | ||
493 | static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count, | |
494 | bool nonblock) | |
495 | { | |
496 | struct scatterlist sg[1]; | |
497 | struct virtqueue *out_vq; | |
498 | ssize_t ret; | |
499 | unsigned long flags; | |
500 | unsigned int len; | |
501 | ||
502 | out_vq = port->out_vq; | |
503 | ||
504 | spin_lock_irqsave(&port->outvq_lock, flags); | |
505 | ||
506 | reclaim_consumed_buffers(port); | |
507 | ||
508 | sg_init_one(sg, in_buf, in_count); | |
509 | ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf); | |
510 | ||
511 | /* Tell Host to go! */ | |
512 | virtqueue_kick(out_vq); | |
513 | ||
514 | if (ret < 0) { | |
515 | in_count = 0; | |
516 | goto done; | |
517 | } | |
518 | ||
519 | if (ret == 0) | |
520 | port->outvq_full = true; | |
521 | ||
522 | if (nonblock) | |
523 | goto done; | |
524 | ||
525 | /* | |
526 | * Wait till the host acknowledges it pushed out the data we | |
527 | * sent. This is done for data from the hvc_console; the tty | |
528 | * operations are performed with spinlocks held so we can't | |
529 | * sleep here. An alternative would be to copy the data to a | |
530 | * buffer and relax the spinning requirement. The downside is | |
531 | * we need to kmalloc a GFP_ATOMIC buffer each time the | |
532 | * console driver writes something out. | |
533 | */ | |
534 | while (!virtqueue_get_buf(out_vq, &len)) | |
535 | cpu_relax(); | |
536 | done: | |
537 | spin_unlock_irqrestore(&port->outvq_lock, flags); | |
538 | ||
539 | port->stats.bytes_sent += in_count; | |
540 | /* | |
541 | * We're expected to return the amount of data we wrote -- all | |
542 | * of it | |
543 | */ | |
544 | return in_count; | |
545 | } | |
546 | ||
547 | /* | |
548 | * Give out the data that's requested from the buffer that we have | |
549 | * queued up. | |
550 | */ | |
551 | static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count, | |
552 | bool to_user) | |
553 | { | |
554 | struct port_buffer *buf; | |
555 | unsigned long flags; | |
556 | ||
557 | if (!out_count || !port_has_data(port)) | |
558 | return 0; | |
559 | ||
560 | buf = port->inbuf; | |
561 | out_count = min(out_count, buf->len - buf->offset); | |
562 | ||
563 | if (to_user) { | |
564 | ssize_t ret; | |
565 | ||
566 | ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count); | |
567 | if (ret) | |
568 | return -EFAULT; | |
569 | } else { | |
570 | memcpy(out_buf, buf->buf + buf->offset, out_count); | |
571 | } | |
572 | ||
573 | buf->offset += out_count; | |
574 | ||
575 | if (buf->offset == buf->len) { | |
576 | /* | |
577 | * We're done using all the data in this buffer. | |
578 | * Re-queue so that the Host can send us more data. | |
579 | */ | |
580 | spin_lock_irqsave(&port->inbuf_lock, flags); | |
581 | port->inbuf = NULL; | |
582 | ||
583 | if (add_inbuf(port->in_vq, buf) < 0) | |
584 | dev_warn(port->dev, "failed add_buf\n"); | |
585 | ||
586 | spin_unlock_irqrestore(&port->inbuf_lock, flags); | |
587 | } | |
588 | /* Return the number of bytes actually copied */ | |
589 | return out_count; | |
590 | } | |
591 | ||
592 | /* The condition that must be true for polling to end */ | |
593 | static bool will_read_block(struct port *port) | |
594 | { | |
595 | if (!port->guest_connected) { | |
596 | /* Port got hot-unplugged. Let's exit. */ | |
597 | return false; | |
598 | } | |
599 | return !port_has_data(port) && port->host_connected; | |
600 | } | |
601 | ||
602 | static bool will_write_block(struct port *port) | |
603 | { | |
604 | bool ret; | |
605 | ||
606 | if (!port->guest_connected) { | |
607 | /* Port got hot-unplugged. Let's exit. */ | |
608 | return false; | |
609 | } | |
610 | if (!port->host_connected) | |
611 | return true; | |
612 | ||
613 | spin_lock_irq(&port->outvq_lock); | |
614 | /* | |
615 | * Check if the Host has consumed any buffers since we last | |
616 | * sent data (this is only applicable for nonblocking ports). | |
617 | */ | |
618 | reclaim_consumed_buffers(port); | |
619 | ret = port->outvq_full; | |
620 | spin_unlock_irq(&port->outvq_lock); | |
621 | ||
622 | return ret; | |
623 | } | |
624 | ||
625 | static ssize_t port_fops_read(struct file *filp, char __user *ubuf, | |
626 | size_t count, loff_t *offp) | |
627 | { | |
628 | struct port *port; | |
629 | ssize_t ret; | |
630 | ||
631 | port = filp->private_data; | |
632 | ||
633 | if (!port_has_data(port)) { | |
634 | /* | |
635 | * If nothing's connected on the host just return 0 in | |
636 | * case of list_empty; this tells the userspace app | |
637 | * that there's no connection | |
638 | */ | |
639 | if (!port->host_connected) | |
640 | return 0; | |
641 | if (filp->f_flags & O_NONBLOCK) | |
642 | return -EAGAIN; | |
643 | ||
644 | ret = wait_event_freezable(port->waitqueue, | |
645 | !will_read_block(port)); | |
646 | if (ret < 0) | |
647 | return ret; | |
648 | } | |
649 | /* Port got hot-unplugged. */ | |
650 | if (!port->guest_connected) | |
651 | return -ENODEV; | |
652 | /* | |
653 | * We could've received a disconnection message while we were | |
654 | * waiting for more data. | |
655 | * | |
656 | * This check is not clubbed in the if() statement above as we | |
657 | * might receive some data as well as the host could get | |
658 | * disconnected after we got woken up from our wait. So we | |
659 | * really want to give off whatever data we have and only then | |
660 | * check for host_connected. | |
661 | */ | |
662 | if (!port_has_data(port) && !port->host_connected) | |
663 | return 0; | |
664 | ||
665 | return fill_readbuf(port, ubuf, count, true); | |
666 | } | |
667 | ||
668 | static ssize_t port_fops_write(struct file *filp, const char __user *ubuf, | |
669 | size_t count, loff_t *offp) | |
670 | { | |
671 | struct port *port; | |
672 | char *buf; | |
673 | ssize_t ret; | |
674 | bool nonblock; | |
675 | ||
676 | /* Userspace could be out to fool us */ | |
677 | if (!count) | |
678 | return 0; | |
679 | ||
680 | port = filp->private_data; | |
681 | ||
682 | nonblock = filp->f_flags & O_NONBLOCK; | |
683 | ||
684 | if (will_write_block(port)) { | |
685 | if (nonblock) | |
686 | return -EAGAIN; | |
687 | ||
688 | ret = wait_event_freezable(port->waitqueue, | |
689 | !will_write_block(port)); | |
690 | if (ret < 0) | |
691 | return ret; | |
692 | } | |
693 | /* Port got hot-unplugged. */ | |
694 | if (!port->guest_connected) | |
695 | return -ENODEV; | |
696 | ||
697 | count = min((size_t)(32 * 1024), count); | |
698 | ||
699 | buf = kmalloc(count, GFP_KERNEL); | |
700 | if (!buf) | |
701 | return -ENOMEM; | |
702 | ||
703 | ret = copy_from_user(buf, ubuf, count); | |
704 | if (ret) { | |
705 | ret = -EFAULT; | |
706 | goto free_buf; | |
707 | } | |
708 | ||
709 | /* | |
710 | * We now ask send_buf() to not spin for generic ports -- we | |
711 | * can re-use the same code path that non-blocking file | |
712 | * descriptors take for blocking file descriptors since the | |
713 | * wait is already done and we're certain the write will go | |
714 | * through to the host. | |
715 | */ | |
716 | nonblock = true; | |
717 | ret = send_buf(port, buf, count, nonblock); | |
718 | ||
719 | if (nonblock && ret > 0) | |
720 | goto out; | |
721 | ||
722 | free_buf: | |
723 | kfree(buf); | |
724 | out: | |
725 | return ret; | |
726 | } | |
727 | ||
728 | static unsigned int port_fops_poll(struct file *filp, poll_table *wait) | |
729 | { | |
730 | struct port *port; | |
731 | unsigned int ret; | |
732 | ||
733 | port = filp->private_data; | |
734 | poll_wait(filp, &port->waitqueue, wait); | |
735 | ||
736 | if (!port->guest_connected) { | |
737 | /* Port got unplugged */ | |
738 | return POLLHUP; | |
739 | } | |
740 | ret = 0; | |
741 | if (!will_read_block(port)) | |
742 | ret |= POLLIN | POLLRDNORM; | |
743 | if (!will_write_block(port)) | |
744 | ret |= POLLOUT; | |
745 | if (!port->host_connected) | |
746 | ret |= POLLHUP; | |
747 | ||
748 | return ret; | |
749 | } | |
750 | ||
751 | static void remove_port(struct kref *kref); | |
752 | ||
753 | static int port_fops_release(struct inode *inode, struct file *filp) | |
754 | { | |
755 | struct port *port; | |
756 | ||
757 | port = filp->private_data; | |
758 | ||
759 | /* Notify host of port being closed */ | |
760 | send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0); | |
761 | ||
762 | spin_lock_irq(&port->inbuf_lock); | |
763 | port->guest_connected = false; | |
764 | ||
765 | discard_port_data(port); | |
766 | ||
767 | spin_unlock_irq(&port->inbuf_lock); | |
768 | ||
769 | spin_lock_irq(&port->outvq_lock); | |
770 | reclaim_consumed_buffers(port); | |
771 | spin_unlock_irq(&port->outvq_lock); | |
772 | ||
773 | /* | |
774 | * Locks aren't necessary here as a port can't be opened after | |
775 | * unplug, and if a port isn't unplugged, a kref would already | |
776 | * exist for the port. Plus, taking ports_lock here would | |
777 | * create a dependency on other locks taken by functions | |
778 | * inside remove_port if we're the last holder of the port, | |
779 | * creating many problems. | |
780 | */ | |
781 | kref_put(&port->kref, remove_port); | |
782 | ||
783 | return 0; | |
784 | } | |
785 | ||
786 | static int port_fops_open(struct inode *inode, struct file *filp) | |
787 | { | |
788 | struct cdev *cdev = inode->i_cdev; | |
789 | struct port *port; | |
790 | int ret; | |
791 | ||
792 | port = find_port_by_devt(cdev->dev); | |
793 | filp->private_data = port; | |
794 | ||
795 | /* Prevent against a port getting hot-unplugged at the same time */ | |
796 | spin_lock_irq(&port->portdev->ports_lock); | |
797 | kref_get(&port->kref); | |
798 | spin_unlock_irq(&port->portdev->ports_lock); | |
799 | ||
800 | /* | |
801 | * Don't allow opening of console port devices -- that's done | |
802 | * via /dev/hvc | |
803 | */ | |
804 | if (is_console_port(port)) { | |
805 | ret = -ENXIO; | |
806 | goto out; | |
807 | } | |
808 | ||
809 | /* Allow only one process to open a particular port at a time */ | |
810 | spin_lock_irq(&port->inbuf_lock); | |
811 | if (port->guest_connected) { | |
812 | spin_unlock_irq(&port->inbuf_lock); | |
813 | ret = -EMFILE; | |
814 | goto out; | |
815 | } | |
816 | ||
817 | port->guest_connected = true; | |
818 | spin_unlock_irq(&port->inbuf_lock); | |
819 | ||
820 | spin_lock_irq(&port->outvq_lock); | |
821 | /* | |
822 | * There might be a chance that we missed reclaiming a few | |
823 | * buffers in the window of the port getting previously closed | |
824 | * and opening now. | |
825 | */ | |
826 | reclaim_consumed_buffers(port); | |
827 | spin_unlock_irq(&port->outvq_lock); | |
828 | ||
829 | nonseekable_open(inode, filp); | |
830 | ||
831 | /* Notify host of port being opened */ | |
832 | send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1); | |
833 | ||
834 | return 0; | |
835 | out: | |
836 | kref_put(&port->kref, remove_port); | |
837 | return ret; | |
838 | } | |
839 | ||
840 | static int port_fops_fasync(int fd, struct file *filp, int mode) | |
841 | { | |
842 | struct port *port; | |
843 | ||
844 | port = filp->private_data; | |
845 | return fasync_helper(fd, filp, mode, &port->async_queue); | |
846 | } | |
847 | ||
848 | /* | |
849 | * The file operations that we support: programs in the guest can open | |
850 | * a console device, read from it, write to it, poll for data and | |
851 | * close it. The devices are at | |
852 | * /dev/vport<device number>p<port number> | |
853 | */ | |
854 | static const struct file_operations port_fops = { | |
855 | .owner = THIS_MODULE, | |
856 | .open = port_fops_open, | |
857 | .read = port_fops_read, | |
858 | .write = port_fops_write, | |
859 | .poll = port_fops_poll, | |
860 | .release = port_fops_release, | |
861 | .fasync = port_fops_fasync, | |
862 | .llseek = no_llseek, | |
863 | }; | |
864 | ||
865 | /* | |
866 | * The put_chars() callback is pretty straightforward. | |
867 | * | |
868 | * We turn the characters into a scatter-gather list, add it to the | |
869 | * output queue and then kick the Host. Then we sit here waiting for | |
870 | * it to finish: inefficient in theory, but in practice | |
871 | * implementations will do it immediately (lguest's Launcher does). | |
872 | */ | |
873 | static int put_chars(u32 vtermno, const char *buf, int count) | |
874 | { | |
875 | struct port *port; | |
876 | ||
877 | if (unlikely(early_put_chars)) | |
878 | return early_put_chars(vtermno, buf, count); | |
879 | ||
880 | port = find_port_by_vtermno(vtermno); | |
881 | if (!port) | |
882 | return -EPIPE; | |
883 | ||
884 | return send_buf(port, (void *)buf, count, false); | |
885 | } | |
886 | ||
887 | /* | |
888 | * get_chars() is the callback from the hvc_console infrastructure | |
889 | * when an interrupt is received. | |
890 | * | |
891 | * We call out to fill_readbuf that gets us the required data from the | |
892 | * buffers that are queued up. | |
893 | */ | |
894 | static int get_chars(u32 vtermno, char *buf, int count) | |
895 | { | |
896 | struct port *port; | |
897 | ||
898 | /* If we've not set up the port yet, we have no input to give. */ | |
899 | if (unlikely(early_put_chars)) | |
900 | return 0; | |
901 | ||
902 | port = find_port_by_vtermno(vtermno); | |
903 | if (!port) | |
904 | return -EPIPE; | |
905 | ||
906 | /* If we don't have an input queue yet, we can't get input. */ | |
907 | BUG_ON(!port->in_vq); | |
908 | ||
909 | return fill_readbuf(port, buf, count, false); | |
910 | } | |
911 | ||
912 | static void resize_console(struct port *port) | |
913 | { | |
914 | struct virtio_device *vdev; | |
915 | ||
916 | /* The port could have been hot-unplugged */ | |
917 | if (!port || !is_console_port(port)) | |
918 | return; | |
919 | ||
920 | vdev = port->portdev->vdev; | |
921 | if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE)) | |
922 | hvc_resize(port->cons.hvc, port->cons.ws); | |
923 | } | |
924 | ||
925 | /* We set the configuration at this point, since we now have a tty */ | |
926 | static int notifier_add_vio(struct hvc_struct *hp, int data) | |
927 | { | |
928 | struct port *port; | |
929 | ||
930 | port = find_port_by_vtermno(hp->vtermno); | |
931 | if (!port) | |
932 | return -EINVAL; | |
933 | ||
934 | hp->irq_requested = 1; | |
935 | resize_console(port); | |
936 | ||
937 | return 0; | |
938 | } | |
939 | ||
940 | static void notifier_del_vio(struct hvc_struct *hp, int data) | |
941 | { | |
942 | hp->irq_requested = 0; | |
943 | } | |
944 | ||
945 | /* The operations for console ports. */ | |
946 | static const struct hv_ops hv_ops = { | |
947 | .get_chars = get_chars, | |
948 | .put_chars = put_chars, | |
949 | .notifier_add = notifier_add_vio, | |
950 | .notifier_del = notifier_del_vio, | |
951 | .notifier_hangup = notifier_del_vio, | |
952 | }; | |
953 | ||
954 | /* | |
955 | * Console drivers are initialized very early so boot messages can go | |
956 | * out, so we do things slightly differently from the generic virtio | |
957 | * initialization of the net and block drivers. | |
958 | * | |
959 | * At this stage, the console is output-only. It's too early to set | |
960 | * up a virtqueue, so we let the drivers do some boutique early-output | |
961 | * thing. | |
962 | */ | |
963 | int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int)) | |
964 | { | |
965 | early_put_chars = put_chars; | |
966 | return hvc_instantiate(0, 0, &hv_ops); | |
967 | } | |
968 | ||
969 | int init_port_console(struct port *port) | |
970 | { | |
971 | int ret; | |
972 | ||
973 | /* | |
974 | * The Host's telling us this port is a console port. Hook it | |
975 | * up with an hvc console. | |
976 | * | |
977 | * To set up and manage our virtual console, we call | |
978 | * hvc_alloc(). | |
979 | * | |
980 | * The first argument of hvc_alloc() is the virtual console | |
981 | * number. The second argument is the parameter for the | |
982 | * notification mechanism (like irq number). We currently | |
983 | * leave this as zero, virtqueues have implicit notifications. | |
984 | * | |
985 | * The third argument is a "struct hv_ops" containing the | |
986 | * put_chars() get_chars(), notifier_add() and notifier_del() | |
987 | * pointers. The final argument is the output buffer size: we | |
988 | * can do any size, so we put PAGE_SIZE here. | |
989 | */ | |
990 | port->cons.vtermno = pdrvdata.next_vtermno; | |
991 | ||
992 | port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE); | |
993 | if (IS_ERR(port->cons.hvc)) { | |
994 | ret = PTR_ERR(port->cons.hvc); | |
995 | dev_err(port->dev, | |
996 | "error %d allocating hvc for port\n", ret); | |
997 | port->cons.hvc = NULL; | |
998 | return ret; | |
999 | } | |
1000 | spin_lock_irq(&pdrvdata_lock); | |
1001 | pdrvdata.next_vtermno++; | |
1002 | list_add_tail(&port->cons.list, &pdrvdata.consoles); | |
1003 | spin_unlock_irq(&pdrvdata_lock); | |
1004 | port->guest_connected = true; | |
1005 | ||
1006 | /* | |
1007 | * Start using the new console output if this is the first | |
1008 | * console to come up. | |
1009 | */ | |
1010 | if (early_put_chars) | |
1011 | early_put_chars = NULL; | |
1012 | ||
1013 | /* Notify host of port being opened */ | |
1014 | send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1); | |
1015 | ||
1016 | return 0; | |
1017 | } | |
1018 | ||
1019 | static ssize_t show_port_name(struct device *dev, | |
1020 | struct device_attribute *attr, char *buffer) | |
1021 | { | |
1022 | struct port *port; | |
1023 | ||
1024 | port = dev_get_drvdata(dev); | |
1025 | ||
1026 | return sprintf(buffer, "%s\n", port->name); | |
1027 | } | |
1028 | ||
1029 | static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL); | |
1030 | ||
1031 | static struct attribute *port_sysfs_entries[] = { | |
1032 | &dev_attr_name.attr, | |
1033 | NULL | |
1034 | }; | |
1035 | ||
1036 | static struct attribute_group port_attribute_group = { | |
1037 | .name = NULL, /* put in device directory */ | |
1038 | .attrs = port_sysfs_entries, | |
1039 | }; | |
1040 | ||
1041 | static int debugfs_open(struct inode *inode, struct file *filp) | |
1042 | { | |
1043 | filp->private_data = inode->i_private; | |
1044 | return 0; | |
1045 | } | |
1046 | ||
1047 | static ssize_t debugfs_read(struct file *filp, char __user *ubuf, | |
1048 | size_t count, loff_t *offp) | |
1049 | { | |
1050 | struct port *port; | |
1051 | char *buf; | |
1052 | ssize_t ret, out_offset, out_count; | |
1053 | ||
1054 | out_count = 1024; | |
1055 | buf = kmalloc(out_count, GFP_KERNEL); | |
1056 | if (!buf) | |
1057 | return -ENOMEM; | |
1058 | ||
1059 | port = filp->private_data; | |
1060 | out_offset = 0; | |
1061 | out_offset += snprintf(buf + out_offset, out_count, | |
1062 | "name: %s\n", port->name ? port->name : ""); | |
1063 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1064 | "guest_connected: %d\n", port->guest_connected); | |
1065 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1066 | "host_connected: %d\n", port->host_connected); | |
1067 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1068 | "outvq_full: %d\n", port->outvq_full); | |
1069 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1070 | "bytes_sent: %lu\n", port->stats.bytes_sent); | |
1071 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1072 | "bytes_received: %lu\n", | |
1073 | port->stats.bytes_received); | |
1074 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1075 | "bytes_discarded: %lu\n", | |
1076 | port->stats.bytes_discarded); | |
1077 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1078 | "is_console: %s\n", | |
1079 | is_console_port(port) ? "yes" : "no"); | |
1080 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1081 | "console_vtermno: %u\n", port->cons.vtermno); | |
1082 | ||
1083 | ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); | |
1084 | kfree(buf); | |
1085 | return ret; | |
1086 | } | |
1087 | ||
1088 | static const struct file_operations port_debugfs_ops = { | |
1089 | .owner = THIS_MODULE, | |
1090 | .open = debugfs_open, | |
1091 | .read = debugfs_read, | |
1092 | }; | |
1093 | ||
1094 | static void set_console_size(struct port *port, u16 rows, u16 cols) | |
1095 | { | |
1096 | if (!port || !is_console_port(port)) | |
1097 | return; | |
1098 | ||
1099 | port->cons.ws.ws_row = rows; | |
1100 | port->cons.ws.ws_col = cols; | |
1101 | } | |
1102 | ||
1103 | static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock) | |
1104 | { | |
1105 | struct port_buffer *buf; | |
1106 | unsigned int nr_added_bufs; | |
1107 | int ret; | |
1108 | ||
1109 | nr_added_bufs = 0; | |
1110 | do { | |
1111 | buf = alloc_buf(PAGE_SIZE); | |
1112 | if (!buf) | |
1113 | break; | |
1114 | ||
1115 | spin_lock_irq(lock); | |
1116 | ret = add_inbuf(vq, buf); | |
1117 | if (ret < 0) { | |
1118 | spin_unlock_irq(lock); | |
1119 | free_buf(buf); | |
1120 | break; | |
1121 | } | |
1122 | nr_added_bufs++; | |
1123 | spin_unlock_irq(lock); | |
1124 | } while (ret > 0); | |
1125 | ||
1126 | return nr_added_bufs; | |
1127 | } | |
1128 | ||
1129 | static void send_sigio_to_port(struct port *port) | |
1130 | { | |
1131 | if (port->async_queue && port->guest_connected) | |
1132 | kill_fasync(&port->async_queue, SIGIO, POLL_OUT); | |
1133 | } | |
1134 | ||
1135 | static int add_port(struct ports_device *portdev, u32 id) | |
1136 | { | |
1137 | char debugfs_name[16]; | |
1138 | struct port *port; | |
1139 | struct port_buffer *buf; | |
1140 | dev_t devt; | |
1141 | unsigned int nr_added_bufs; | |
1142 | int err; | |
1143 | ||
1144 | port = kmalloc(sizeof(*port), GFP_KERNEL); | |
1145 | if (!port) { | |
1146 | err = -ENOMEM; | |
1147 | goto fail; | |
1148 | } | |
1149 | kref_init(&port->kref); | |
1150 | ||
1151 | port->portdev = portdev; | |
1152 | port->id = id; | |
1153 | ||
1154 | port->name = NULL; | |
1155 | port->inbuf = NULL; | |
1156 | port->cons.hvc = NULL; | |
1157 | port->async_queue = NULL; | |
1158 | ||
1159 | port->cons.ws.ws_row = port->cons.ws.ws_col = 0; | |
1160 | ||
1161 | port->host_connected = port->guest_connected = false; | |
1162 | port->stats = (struct port_stats) { 0 }; | |
1163 | ||
1164 | port->outvq_full = false; | |
1165 | ||
1166 | port->in_vq = portdev->in_vqs[port->id]; | |
1167 | port->out_vq = portdev->out_vqs[port->id]; | |
1168 | ||
1169 | port->cdev = cdev_alloc(); | |
1170 | if (!port->cdev) { | |
1171 | dev_err(&port->portdev->vdev->dev, "Error allocating cdev\n"); | |
1172 | err = -ENOMEM; | |
1173 | goto free_port; | |
1174 | } | |
1175 | port->cdev->ops = &port_fops; | |
1176 | ||
1177 | devt = MKDEV(portdev->chr_major, id); | |
1178 | err = cdev_add(port->cdev, devt, 1); | |
1179 | if (err < 0) { | |
1180 | dev_err(&port->portdev->vdev->dev, | |
1181 | "Error %d adding cdev for port %u\n", err, id); | |
1182 | goto free_cdev; | |
1183 | } | |
1184 | port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev, | |
1185 | devt, port, "vport%up%u", | |
1186 | port->portdev->drv_index, id); | |
1187 | if (IS_ERR(port->dev)) { | |
1188 | err = PTR_ERR(port->dev); | |
1189 | dev_err(&port->portdev->vdev->dev, | |
1190 | "Error %d creating device for port %u\n", | |
1191 | err, id); | |
1192 | goto free_cdev; | |
1193 | } | |
1194 | ||
1195 | spin_lock_init(&port->inbuf_lock); | |
1196 | spin_lock_init(&port->outvq_lock); | |
1197 | init_waitqueue_head(&port->waitqueue); | |
1198 | ||
1199 | /* Fill the in_vq with buffers so the host can send us data. */ | |
1200 | nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock); | |
1201 | if (!nr_added_bufs) { | |
1202 | dev_err(port->dev, "Error allocating inbufs\n"); | |
1203 | err = -ENOMEM; | |
1204 | goto free_device; | |
1205 | } | |
1206 | ||
1207 | /* | |
1208 | * If we're not using multiport support, this has to be a console port | |
1209 | */ | |
1210 | if (!use_multiport(port->portdev)) { | |
1211 | err = init_port_console(port); | |
1212 | if (err) | |
1213 | goto free_inbufs; | |
1214 | } | |
1215 | ||
1216 | spin_lock_irq(&portdev->ports_lock); | |
1217 | list_add_tail(&port->list, &port->portdev->ports); | |
1218 | spin_unlock_irq(&portdev->ports_lock); | |
1219 | ||
1220 | /* | |
1221 | * Tell the Host we're set so that it can send us various | |
1222 | * configuration parameters for this port (eg, port name, | |
1223 | * caching, whether this is a console port, etc.) | |
1224 | */ | |
1225 | send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1); | |
1226 | ||
1227 | if (pdrvdata.debugfs_dir) { | |
1228 | /* | |
1229 | * Finally, create the debugfs file that we can use to | |
1230 | * inspect a port's state at any time | |
1231 | */ | |
1232 | sprintf(debugfs_name, "vport%up%u", | |
1233 | port->portdev->drv_index, id); | |
1234 | port->debugfs_file = debugfs_create_file(debugfs_name, 0444, | |
1235 | pdrvdata.debugfs_dir, | |
1236 | port, | |
1237 | &port_debugfs_ops); | |
1238 | } | |
1239 | return 0; | |
1240 | ||
1241 | free_inbufs: | |
1242 | while ((buf = virtqueue_detach_unused_buf(port->in_vq))) | |
1243 | free_buf(buf); | |
1244 | free_device: | |
1245 | device_destroy(pdrvdata.class, port->dev->devt); | |
1246 | free_cdev: | |
1247 | cdev_del(port->cdev); | |
1248 | free_port: | |
1249 | kfree(port); | |
1250 | fail: | |
1251 | /* The host might want to notify management sw about port add failure */ | |
1252 | __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0); | |
1253 | return err; | |
1254 | } | |
1255 | ||
1256 | /* No users remain, remove all port-specific data. */ | |
1257 | static void remove_port(struct kref *kref) | |
1258 | { | |
1259 | struct port *port; | |
1260 | ||
1261 | port = container_of(kref, struct port, kref); | |
1262 | ||
1263 | sysfs_remove_group(&port->dev->kobj, &port_attribute_group); | |
1264 | device_destroy(pdrvdata.class, port->dev->devt); | |
1265 | cdev_del(port->cdev); | |
1266 | ||
1267 | kfree(port->name); | |
1268 | ||
1269 | debugfs_remove(port->debugfs_file); | |
1270 | ||
1271 | kfree(port); | |
1272 | } | |
1273 | ||
1274 | /* | |
1275 | * Port got unplugged. Remove port from portdev's list and drop the | |
1276 | * kref reference. If no userspace has this port opened, it will | |
1277 | * result in immediate removal the port. | |
1278 | */ | |
1279 | static void unplug_port(struct port *port) | |
1280 | { | |
1281 | struct port_buffer *buf; | |
1282 | ||
1283 | spin_lock_irq(&port->portdev->ports_lock); | |
1284 | list_del(&port->list); | |
1285 | spin_unlock_irq(&port->portdev->ports_lock); | |
1286 | ||
1287 | if (port->guest_connected) { | |
1288 | port->guest_connected = false; | |
1289 | port->host_connected = false; | |
1290 | wake_up_interruptible(&port->waitqueue); | |
1291 | ||
1292 | /* Let the app know the port is going down. */ | |
1293 | send_sigio_to_port(port); | |
1294 | } | |
1295 | ||
1296 | if (is_console_port(port)) { | |
1297 | spin_lock_irq(&pdrvdata_lock); | |
1298 | list_del(&port->cons.list); | |
1299 | spin_unlock_irq(&pdrvdata_lock); | |
1300 | hvc_remove(port->cons.hvc); | |
1301 | } | |
1302 | ||
1303 | /* Remove unused data this port might have received. */ | |
1304 | discard_port_data(port); | |
1305 | ||
1306 | reclaim_consumed_buffers(port); | |
1307 | ||
1308 | /* Remove buffers we queued up for the Host to send us data in. */ | |
1309 | while ((buf = virtqueue_detach_unused_buf(port->in_vq))) | |
1310 | free_buf(buf); | |
1311 | ||
1312 | /* | |
1313 | * We should just assume the device itself has gone off -- | |
1314 | * else a close on an open port later will try to send out a | |
1315 | * control message. | |
1316 | */ | |
1317 | port->portdev = NULL; | |
1318 | ||
1319 | /* | |
1320 | * Locks around here are not necessary - a port can't be | |
1321 | * opened after we removed the port struct from ports_list | |
1322 | * above. | |
1323 | */ | |
1324 | kref_put(&port->kref, remove_port); | |
1325 | } | |
1326 | ||
1327 | /* Any private messages that the Host and Guest want to share */ | |
1328 | static void handle_control_message(struct ports_device *portdev, | |
1329 | struct port_buffer *buf) | |
1330 | { | |
1331 | struct virtio_console_control *cpkt; | |
1332 | struct port *port; | |
1333 | size_t name_size; | |
1334 | int err; | |
1335 | ||
1336 | cpkt = (struct virtio_console_control *)(buf->buf + buf->offset); | |
1337 | ||
1338 | port = find_port_by_id(portdev, cpkt->id); | |
1339 | if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) { | |
1340 | /* No valid header at start of buffer. Drop it. */ | |
1341 | dev_dbg(&portdev->vdev->dev, | |
1342 | "Invalid index %u in control packet\n", cpkt->id); | |
1343 | return; | |
1344 | } | |
1345 | ||
1346 | switch (cpkt->event) { | |
1347 | case VIRTIO_CONSOLE_PORT_ADD: | |
1348 | if (port) { | |
1349 | dev_dbg(&portdev->vdev->dev, | |
1350 | "Port %u already added\n", port->id); | |
1351 | send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1); | |
1352 | break; | |
1353 | } | |
1354 | if (cpkt->id >= portdev->config.max_nr_ports) { | |
1355 | dev_warn(&portdev->vdev->dev, | |
1356 | "Request for adding port with out-of-bound id %u, max. supported id: %u\n", | |
1357 | cpkt->id, portdev->config.max_nr_ports - 1); | |
1358 | break; | |
1359 | } | |
1360 | add_port(portdev, cpkt->id); | |
1361 | break; | |
1362 | case VIRTIO_CONSOLE_PORT_REMOVE: | |
1363 | unplug_port(port); | |
1364 | break; | |
1365 | case VIRTIO_CONSOLE_CONSOLE_PORT: | |
1366 | if (!cpkt->value) | |
1367 | break; | |
1368 | if (is_console_port(port)) | |
1369 | break; | |
1370 | ||
1371 | init_port_console(port); | |
1372 | complete(&early_console_added); | |
1373 | /* | |
1374 | * Could remove the port here in case init fails - but | |
1375 | * have to notify the host first. | |
1376 | */ | |
1377 | break; | |
1378 | case VIRTIO_CONSOLE_RESIZE: { | |
1379 | struct { | |
1380 | __u16 rows; | |
1381 | __u16 cols; | |
1382 | } size; | |
1383 | ||
1384 | if (!is_console_port(port)) | |
1385 | break; | |
1386 | ||
1387 | memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt), | |
1388 | sizeof(size)); | |
1389 | set_console_size(port, size.rows, size.cols); | |
1390 | ||
1391 | port->cons.hvc->irq_requested = 1; | |
1392 | resize_console(port); | |
1393 | break; | |
1394 | } | |
1395 | case VIRTIO_CONSOLE_PORT_OPEN: | |
1396 | port->host_connected = cpkt->value; | |
1397 | wake_up_interruptible(&port->waitqueue); | |
1398 | /* | |
1399 | * If the host port got closed and the host had any | |
1400 | * unconsumed buffers, we'll be able to reclaim them | |
1401 | * now. | |
1402 | */ | |
1403 | spin_lock_irq(&port->outvq_lock); | |
1404 | reclaim_consumed_buffers(port); | |
1405 | spin_unlock_irq(&port->outvq_lock); | |
1406 | ||
1407 | /* | |
1408 | * If the guest is connected, it'll be interested in | |
1409 | * knowing the host connection state changed. | |
1410 | */ | |
1411 | send_sigio_to_port(port); | |
1412 | break; | |
1413 | case VIRTIO_CONSOLE_PORT_NAME: | |
1414 | /* | |
1415 | * If we woke up after hibernation, we can get this | |
1416 | * again. Skip it in that case. | |
1417 | */ | |
1418 | if (port->name) | |
1419 | break; | |
1420 | ||
1421 | /* | |
1422 | * Skip the size of the header and the cpkt to get the size | |
1423 | * of the name that was sent | |
1424 | */ | |
1425 | name_size = buf->len - buf->offset - sizeof(*cpkt) + 1; | |
1426 | ||
1427 | port->name = kmalloc(name_size, GFP_KERNEL); | |
1428 | if (!port->name) { | |
1429 | dev_err(port->dev, | |
1430 | "Not enough space to store port name\n"); | |
1431 | break; | |
1432 | } | |
1433 | strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt), | |
1434 | name_size - 1); | |
1435 | port->name[name_size - 1] = 0; | |
1436 | ||
1437 | /* | |
1438 | * Since we only have one sysfs attribute, 'name', | |
1439 | * create it only if we have a name for the port. | |
1440 | */ | |
1441 | err = sysfs_create_group(&port->dev->kobj, | |
1442 | &port_attribute_group); | |
1443 | if (err) { | |
1444 | dev_err(port->dev, | |
1445 | "Error %d creating sysfs device attributes\n", | |
1446 | err); | |
1447 | } else { | |
1448 | /* | |
1449 | * Generate a udev event so that appropriate | |
1450 | * symlinks can be created based on udev | |
1451 | * rules. | |
1452 | */ | |
1453 | kobject_uevent(&port->dev->kobj, KOBJ_CHANGE); | |
1454 | } | |
1455 | break; | |
1456 | } | |
1457 | } | |
1458 | ||
1459 | static void control_work_handler(struct work_struct *work) | |
1460 | { | |
1461 | struct ports_device *portdev; | |
1462 | struct virtqueue *vq; | |
1463 | struct port_buffer *buf; | |
1464 | unsigned int len; | |
1465 | ||
1466 | portdev = container_of(work, struct ports_device, control_work); | |
1467 | vq = portdev->c_ivq; | |
1468 | ||
1469 | spin_lock(&portdev->cvq_lock); | |
1470 | while ((buf = virtqueue_get_buf(vq, &len))) { | |
1471 | spin_unlock(&portdev->cvq_lock); | |
1472 | ||
1473 | buf->len = len; | |
1474 | buf->offset = 0; | |
1475 | ||
1476 | handle_control_message(portdev, buf); | |
1477 | ||
1478 | spin_lock(&portdev->cvq_lock); | |
1479 | if (add_inbuf(portdev->c_ivq, buf) < 0) { | |
1480 | dev_warn(&portdev->vdev->dev, | |
1481 | "Error adding buffer to queue\n"); | |
1482 | free_buf(buf); | |
1483 | } | |
1484 | } | |
1485 | spin_unlock(&portdev->cvq_lock); | |
1486 | } | |
1487 | ||
1488 | static void out_intr(struct virtqueue *vq) | |
1489 | { | |
1490 | struct port *port; | |
1491 | ||
1492 | port = find_port_by_vq(vq->vdev->priv, vq); | |
1493 | if (!port) | |
1494 | return; | |
1495 | ||
1496 | wake_up_interruptible(&port->waitqueue); | |
1497 | } | |
1498 | ||
1499 | static void in_intr(struct virtqueue *vq) | |
1500 | { | |
1501 | struct port *port; | |
1502 | unsigned long flags; | |
1503 | ||
1504 | port = find_port_by_vq(vq->vdev->priv, vq); | |
1505 | if (!port) | |
1506 | return; | |
1507 | ||
1508 | spin_lock_irqsave(&port->inbuf_lock, flags); | |
1509 | port->inbuf = get_inbuf(port); | |
1510 | ||
1511 | /* | |
1512 | * Don't queue up data when port is closed. This condition | |
1513 | * can be reached when a console port is not yet connected (no | |
1514 | * tty is spawned) and the host sends out data to console | |
1515 | * ports. For generic serial ports, the host won't | |
1516 | * (shouldn't) send data till the guest is connected. | |
1517 | */ | |
1518 | if (!port->guest_connected) | |
1519 | discard_port_data(port); | |
1520 | ||
1521 | spin_unlock_irqrestore(&port->inbuf_lock, flags); | |
1522 | ||
1523 | wake_up_interruptible(&port->waitqueue); | |
1524 | ||
1525 | /* Send a SIGIO indicating new data in case the process asked for it */ | |
1526 | send_sigio_to_port(port); | |
1527 | ||
1528 | if (is_console_port(port) && hvc_poll(port->cons.hvc)) | |
1529 | hvc_kick(); | |
1530 | } | |
1531 | ||
1532 | static void control_intr(struct virtqueue *vq) | |
1533 | { | |
1534 | struct ports_device *portdev; | |
1535 | ||
1536 | portdev = vq->vdev->priv; | |
1537 | schedule_work(&portdev->control_work); | |
1538 | } | |
1539 | ||
1540 | static void config_intr(struct virtio_device *vdev) | |
1541 | { | |
1542 | struct ports_device *portdev; | |
1543 | ||
1544 | portdev = vdev->priv; | |
1545 | ||
1546 | if (!use_multiport(portdev)) { | |
1547 | struct port *port; | |
1548 | u16 rows, cols; | |
1549 | ||
1550 | vdev->config->get(vdev, | |
1551 | offsetof(struct virtio_console_config, cols), | |
1552 | &cols, sizeof(u16)); | |
1553 | vdev->config->get(vdev, | |
1554 | offsetof(struct virtio_console_config, rows), | |
1555 | &rows, sizeof(u16)); | |
1556 | ||
1557 | port = find_port_by_id(portdev, 0); | |
1558 | set_console_size(port, rows, cols); | |
1559 | ||
1560 | /* | |
1561 | * We'll use this way of resizing only for legacy | |
1562 | * support. For newer userspace | |
1563 | * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages | |
1564 | * to indicate console size changes so that it can be | |
1565 | * done per-port. | |
1566 | */ | |
1567 | resize_console(port); | |
1568 | } | |
1569 | } | |
1570 | ||
1571 | static int init_vqs(struct ports_device *portdev) | |
1572 | { | |
1573 | vq_callback_t **io_callbacks; | |
1574 | char **io_names; | |
1575 | struct virtqueue **vqs; | |
1576 | u32 i, j, nr_ports, nr_queues; | |
1577 | int err; | |
1578 | ||
1579 | nr_ports = portdev->config.max_nr_ports; | |
1580 | nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2; | |
1581 | ||
1582 | vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL); | |
1583 | io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL); | |
1584 | io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL); | |
1585 | portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *), | |
1586 | GFP_KERNEL); | |
1587 | portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *), | |
1588 | GFP_KERNEL); | |
1589 | if (!vqs || !io_callbacks || !io_names || !portdev->in_vqs || | |
1590 | !portdev->out_vqs) { | |
1591 | err = -ENOMEM; | |
1592 | goto free; | |
1593 | } | |
1594 | ||
1595 | /* | |
1596 | * For backward compat (newer host but older guest), the host | |
1597 | * spawns a console port first and also inits the vqs for port | |
1598 | * 0 before others. | |
1599 | */ | |
1600 | j = 0; | |
1601 | io_callbacks[j] = in_intr; | |
1602 | io_callbacks[j + 1] = out_intr; | |
1603 | io_names[j] = "input"; | |
1604 | io_names[j + 1] = "output"; | |
1605 | j += 2; | |
1606 | ||
1607 | if (use_multiport(portdev)) { | |
1608 | io_callbacks[j] = control_intr; | |
1609 | io_callbacks[j + 1] = NULL; | |
1610 | io_names[j] = "control-i"; | |
1611 | io_names[j + 1] = "control-o"; | |
1612 | ||
1613 | for (i = 1; i < nr_ports; i++) { | |
1614 | j += 2; | |
1615 | io_callbacks[j] = in_intr; | |
1616 | io_callbacks[j + 1] = out_intr; | |
1617 | io_names[j] = "input"; | |
1618 | io_names[j + 1] = "output"; | |
1619 | } | |
1620 | } | |
1621 | /* Find the queues. */ | |
1622 | err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs, | |
1623 | io_callbacks, | |
1624 | (const char **)io_names); | |
1625 | if (err) | |
1626 | goto free; | |
1627 | ||
1628 | j = 0; | |
1629 | portdev->in_vqs[0] = vqs[0]; | |
1630 | portdev->out_vqs[0] = vqs[1]; | |
1631 | j += 2; | |
1632 | if (use_multiport(portdev)) { | |
1633 | portdev->c_ivq = vqs[j]; | |
1634 | portdev->c_ovq = vqs[j + 1]; | |
1635 | ||
1636 | for (i = 1; i < nr_ports; i++) { | |
1637 | j += 2; | |
1638 | portdev->in_vqs[i] = vqs[j]; | |
1639 | portdev->out_vqs[i] = vqs[j + 1]; | |
1640 | } | |
1641 | } | |
1642 | kfree(io_names); | |
1643 | kfree(io_callbacks); | |
1644 | kfree(vqs); | |
1645 | ||
1646 | return 0; | |
1647 | ||
1648 | free: | |
1649 | kfree(portdev->out_vqs); | |
1650 | kfree(portdev->in_vqs); | |
1651 | kfree(io_names); | |
1652 | kfree(io_callbacks); | |
1653 | kfree(vqs); | |
1654 | ||
1655 | return err; | |
1656 | } | |
1657 | ||
1658 | static const struct file_operations portdev_fops = { | |
1659 | .owner = THIS_MODULE, | |
1660 | }; | |
1661 | ||
1662 | /* | |
1663 | * Once we're further in boot, we get probed like any other virtio | |
1664 | * device. | |
1665 | * | |
1666 | * If the host also supports multiple console ports, we check the | |
1667 | * config space to see how many ports the host has spawned. We | |
1668 | * initialize each port found. | |
1669 | */ | |
1670 | static int __devinit virtcons_probe(struct virtio_device *vdev) | |
1671 | { | |
1672 | struct ports_device *portdev; | |
1673 | int err; | |
1674 | bool multiport; | |
1675 | bool early = early_put_chars != NULL; | |
1676 | ||
1677 | /* Ensure to read early_put_chars now */ | |
1678 | barrier(); | |
1679 | ||
1680 | portdev = kmalloc(sizeof(*portdev), GFP_KERNEL); | |
1681 | if (!portdev) { | |
1682 | err = -ENOMEM; | |
1683 | goto fail; | |
1684 | } | |
1685 | ||
1686 | /* Attach this portdev to this virtio_device, and vice-versa. */ | |
1687 | portdev->vdev = vdev; | |
1688 | vdev->priv = portdev; | |
1689 | ||
1690 | spin_lock_irq(&pdrvdata_lock); | |
1691 | portdev->drv_index = pdrvdata.index++; | |
1692 | spin_unlock_irq(&pdrvdata_lock); | |
1693 | ||
1694 | portdev->chr_major = register_chrdev(0, "virtio-portsdev", | |
1695 | &portdev_fops); | |
1696 | if (portdev->chr_major < 0) { | |
1697 | dev_err(&vdev->dev, | |
1698 | "Error %d registering chrdev for device %u\n", | |
1699 | portdev->chr_major, portdev->drv_index); | |
1700 | err = portdev->chr_major; | |
1701 | goto free; | |
1702 | } | |
1703 | ||
1704 | multiport = false; | |
1705 | portdev->config.max_nr_ports = 1; | |
1706 | if (virtio_config_val(vdev, VIRTIO_CONSOLE_F_MULTIPORT, | |
1707 | offsetof(struct virtio_console_config, | |
1708 | max_nr_ports), | |
1709 | &portdev->config.max_nr_ports) == 0) | |
1710 | multiport = true; | |
1711 | ||
1712 | err = init_vqs(portdev); | |
1713 | if (err < 0) { | |
1714 | dev_err(&vdev->dev, "Error %d initializing vqs\n", err); | |
1715 | goto free_chrdev; | |
1716 | } | |
1717 | ||
1718 | spin_lock_init(&portdev->ports_lock); | |
1719 | INIT_LIST_HEAD(&portdev->ports); | |
1720 | ||
1721 | if (multiport) { | |
1722 | unsigned int nr_added_bufs; | |
1723 | ||
1724 | spin_lock_init(&portdev->cvq_lock); | |
1725 | INIT_WORK(&portdev->control_work, &control_work_handler); | |
1726 | ||
1727 | nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock); | |
1728 | if (!nr_added_bufs) { | |
1729 | dev_err(&vdev->dev, | |
1730 | "Error allocating buffers for control queue\n"); | |
1731 | err = -ENOMEM; | |
1732 | goto free_vqs; | |
1733 | } | |
1734 | } else { | |
1735 | /* | |
1736 | * For backward compatibility: Create a console port | |
1737 | * if we're running on older host. | |
1738 | */ | |
1739 | add_port(portdev, 0); | |
1740 | } | |
1741 | ||
1742 | spin_lock_irq(&pdrvdata_lock); | |
1743 | list_add_tail(&portdev->list, &pdrvdata.portdevs); | |
1744 | spin_unlock_irq(&pdrvdata_lock); | |
1745 | ||
1746 | __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID, | |
1747 | VIRTIO_CONSOLE_DEVICE_READY, 1); | |
1748 | ||
1749 | /* | |
1750 | * If there was an early virtio console, assume that there are no | |
1751 | * other consoles. We need to wait until the hvc_alloc matches the | |
1752 | * hvc_instantiate, otherwise tty_open will complain, resulting in | |
1753 | * a "Warning: unable to open an initial console" boot failure. | |
1754 | * Without multiport this is done in add_port above. With multiport | |
1755 | * this might take some host<->guest communication - thus we have to | |
1756 | * wait. | |
1757 | */ | |
1758 | if (multiport && early) | |
1759 | wait_for_completion(&early_console_added); | |
1760 | ||
1761 | return 0; | |
1762 | ||
1763 | free_vqs: | |
1764 | /* The host might want to notify mgmt sw about device add failure */ | |
1765 | __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID, | |
1766 | VIRTIO_CONSOLE_DEVICE_READY, 0); | |
1767 | vdev->config->del_vqs(vdev); | |
1768 | kfree(portdev->in_vqs); | |
1769 | kfree(portdev->out_vqs); | |
1770 | free_chrdev: | |
1771 | unregister_chrdev(portdev->chr_major, "virtio-portsdev"); | |
1772 | free: | |
1773 | kfree(portdev); | |
1774 | fail: | |
1775 | return err; | |
1776 | } | |
1777 | ||
1778 | static void virtcons_remove(struct virtio_device *vdev) | |
1779 | { | |
1780 | struct ports_device *portdev; | |
1781 | struct port *port, *port2; | |
1782 | ||
1783 | portdev = vdev->priv; | |
1784 | ||
1785 | spin_lock_irq(&pdrvdata_lock); | |
1786 | list_del(&portdev->list); | |
1787 | spin_unlock_irq(&pdrvdata_lock); | |
1788 | ||
1789 | /* Disable interrupts for vqs */ | |
1790 | vdev->config->reset(vdev); | |
1791 | /* Finish up work that's lined up */ | |
1792 | cancel_work_sync(&portdev->control_work); | |
1793 | ||
1794 | list_for_each_entry_safe(port, port2, &portdev->ports, list) | |
1795 | unplug_port(port); | |
1796 | ||
1797 | unregister_chrdev(portdev->chr_major, "virtio-portsdev"); | |
1798 | ||
1799 | /* | |
1800 | * When yanking out a device, we immediately lose the | |
1801 | * (device-side) queues. So there's no point in keeping the | |
1802 | * guest side around till we drop our final reference. This | |
1803 | * also means that any ports which are in an open state will | |
1804 | * have to just stop using the port, as the vqs are going | |
1805 | * away. | |
1806 | */ | |
1807 | if (use_multiport(portdev)) { | |
1808 | struct port_buffer *buf; | |
1809 | unsigned int len; | |
1810 | ||
1811 | while ((buf = virtqueue_get_buf(portdev->c_ivq, &len))) | |
1812 | free_buf(buf); | |
1813 | ||
1814 | while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq))) | |
1815 | free_buf(buf); | |
1816 | } | |
1817 | ||
1818 | vdev->config->del_vqs(vdev); | |
1819 | kfree(portdev->in_vqs); | |
1820 | kfree(portdev->out_vqs); | |
1821 | ||
1822 | kfree(portdev); | |
1823 | } | |
1824 | ||
1825 | static struct virtio_device_id id_table[] = { | |
1826 | { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID }, | |
1827 | { 0 }, | |
1828 | }; | |
1829 | ||
1830 | static unsigned int features[] = { | |
1831 | VIRTIO_CONSOLE_F_SIZE, | |
1832 | VIRTIO_CONSOLE_F_MULTIPORT, | |
1833 | }; | |
1834 | ||
1835 | static struct virtio_driver virtio_console = { | |
1836 | .feature_table = features, | |
1837 | .feature_table_size = ARRAY_SIZE(features), | |
1838 | .driver.name = KBUILD_MODNAME, | |
1839 | .driver.owner = THIS_MODULE, | |
1840 | .id_table = id_table, | |
1841 | .probe = virtcons_probe, | |
1842 | .remove = virtcons_remove, | |
1843 | .config_changed = config_intr, | |
1844 | }; | |
1845 | ||
1846 | static int __init init(void) | |
1847 | { | |
1848 | int err; | |
1849 | ||
1850 | pdrvdata.class = class_create(THIS_MODULE, "virtio-ports"); | |
1851 | if (IS_ERR(pdrvdata.class)) { | |
1852 | err = PTR_ERR(pdrvdata.class); | |
1853 | pr_err("Error %d creating virtio-ports class\n", err); | |
1854 | return err; | |
1855 | } | |
1856 | ||
1857 | pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL); | |
1858 | if (!pdrvdata.debugfs_dir) { | |
1859 | pr_warning("Error %ld creating debugfs dir for virtio-ports\n", | |
1860 | PTR_ERR(pdrvdata.debugfs_dir)); | |
1861 | } | |
1862 | INIT_LIST_HEAD(&pdrvdata.consoles); | |
1863 | INIT_LIST_HEAD(&pdrvdata.portdevs); | |
1864 | ||
1865 | return register_virtio_driver(&virtio_console); | |
1866 | } | |
1867 | ||
1868 | static void __exit fini(void) | |
1869 | { | |
1870 | unregister_virtio_driver(&virtio_console); | |
1871 | ||
1872 | class_destroy(pdrvdata.class); | |
1873 | if (pdrvdata.debugfs_dir) | |
1874 | debugfs_remove_recursive(pdrvdata.debugfs_dir); | |
1875 | } | |
1876 | module_init(init); | |
1877 | module_exit(fini); | |
1878 | ||
1879 | MODULE_DEVICE_TABLE(virtio, id_table); | |
1880 | MODULE_DESCRIPTION("Virtio console driver"); | |
1881 | MODULE_LICENSE("GPL"); |