virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0
[deliverable/linux.git] / drivers / char / virtio_console.c
CommitLineData
a23ea924
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1/*
2 * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
5084f893
AS
3 * Copyright (C) 2009, 2010, 2011 Red Hat, Inc.
4 * Copyright (C) 2009, 2010, 2011 Amit Shah <amit.shah@redhat.com>
31610434
RR
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 */
fb08bd27 20#include <linux/cdev.h>
d99393ef 21#include <linux/debugfs.h>
5e38483b 22#include <linux/completion.h>
fb08bd27 23#include <linux/device.h>
31610434 24#include <linux/err.h>
a08fa92d 25#include <linux/freezer.h>
2030fa49 26#include <linux/fs.h>
eb5e89fc
MH
27#include <linux/splice.h>
28#include <linux/pagemap.h>
31610434 29#include <linux/init.h>
38edf58d 30#include <linux/list.h>
2030fa49
AS
31#include <linux/poll.h>
32#include <linux/sched.h>
5a0e3ad6 33#include <linux/slab.h>
38edf58d 34#include <linux/spinlock.h>
31610434
RR
35#include <linux/virtio.h>
36#include <linux/virtio_console.h>
2030fa49 37#include <linux/wait.h>
17634ba2 38#include <linux/workqueue.h>
c22405c9 39#include <linux/module.h>
51df0acc 40#include "../tty/hvc/hvc_console.h"
31610434 41
38edf58d
AS
42/*
43 * This is a global struct for storing common data for all the devices
44 * this driver handles.
45 *
46 * Mainly, it has a linked list for all the consoles in one place so
47 * that callbacks from hvc for get_chars(), put_chars() work properly
48 * across multiple devices and multiple ports per device.
49 */
50struct ports_driver_data {
fb08bd27
AS
51 /* Used for registering chardevs */
52 struct class *class;
53
d99393ef
AS
54 /* Used for exporting per-port information to debugfs */
55 struct dentry *debugfs_dir;
56
6bdf2afd
AS
57 /* List of all the devices we're handling */
58 struct list_head portdevs;
59
fb08bd27
AS
60 /* Number of devices this driver is handling */
61 unsigned int index;
62
d8a02bd5
RR
63 /*
64 * This is used to keep track of the number of hvc consoles
65 * spawned by this driver. This number is given as the first
66 * argument to hvc_alloc(). To correctly map an initial
67 * console spawned via hvc_instantiate to the console being
68 * hooked up via hvc_alloc, we need to pass the same vtermno.
69 *
70 * We also just assume the first console being initialised was
71 * the first one that got used as the initial console.
72 */
73 unsigned int next_vtermno;
74
38edf58d
AS
75 /* All the console devices handled by this driver */
76 struct list_head consoles;
77};
78static struct ports_driver_data pdrvdata;
79
80DEFINE_SPINLOCK(pdrvdata_lock);
5e38483b 81DECLARE_COMPLETION(early_console_added);
38edf58d 82
4f23c573
AS
83/* This struct holds information that's relevant only for console ports */
84struct console {
85 /* We'll place all consoles in a list in the pdrvdata struct */
86 struct list_head list;
87
88 /* The hvc device associated with this console port */
89 struct hvc_struct *hvc;
90
9778829c
AS
91 /* The size of the console */
92 struct winsize ws;
93
4f23c573
AS
94 /*
95 * This number identifies the number that we used to register
96 * with hvc in hvc_instantiate() and hvc_alloc(); this is the
97 * number passed on by the hvc callbacks to us to
98 * differentiate between the other console ports handled by
99 * this driver
100 */
101 u32 vtermno;
102};
103
fdb9a054
AS
104struct port_buffer {
105 char *buf;
106
107 /* size of the buffer in *buf above */
108 size_t size;
109
110 /* used length of the buffer */
111 size_t len;
112 /* offset in the buf from which to consume data */
113 size_t offset;
114};
115
17634ba2
AS
116/*
117 * This is a per-device struct that stores data common to all the
118 * ports for that device (vdev->priv).
119 */
120struct ports_device {
6bdf2afd
AS
121 /* Next portdev in the list, head is in the pdrvdata struct */
122 struct list_head list;
123
17634ba2
AS
124 /*
125 * Workqueue handlers where we process deferred work after
126 * notification
127 */
128 struct work_struct control_work;
129
130 struct list_head ports;
131
132 /* To protect the list of ports */
133 spinlock_t ports_lock;
134
135 /* To protect the vq operations for the control channel */
136 spinlock_t cvq_lock;
137
138 /* The current config space is stored here */
b99fa815 139 struct virtio_console_config config;
17634ba2
AS
140
141 /* The virtio device we're associated with */
142 struct virtio_device *vdev;
143
144 /*
145 * A couple of virtqueues for the control channel: one for
146 * guest->host transfers, one for host->guest transfers
147 */
148 struct virtqueue *c_ivq, *c_ovq;
149
150 /* Array of per-port IO virtqueues */
151 struct virtqueue **in_vqs, **out_vqs;
fb08bd27
AS
152
153 /* Used for numbering devices for sysfs and debugfs */
154 unsigned int drv_index;
155
156 /* Major number for this device. Ports will be created as minors. */
157 int chr_major;
17634ba2
AS
158};
159
17e5b4f2
AS
160struct port_stats {
161 unsigned long bytes_sent, bytes_received, bytes_discarded;
162};
163
1c85bf35 164/* This struct holds the per-port data */
21206ede 165struct port {
17634ba2
AS
166 /* Next port in the list, head is in the ports_device */
167 struct list_head list;
168
1c85bf35
AS
169 /* Pointer to the parent virtio_console device */
170 struct ports_device *portdev;
fdb9a054
AS
171
172 /* The current buffer from which data has to be fed to readers */
173 struct port_buffer *inbuf;
21206ede 174
203baab8
AS
175 /*
176 * To protect the operations on the in_vq associated with this
177 * port. Has to be a spinlock because it can be called from
178 * interrupt context (get_char()).
179 */
180 spinlock_t inbuf_lock;
181
cdfadfc1
AS
182 /* Protect the operations on the out_vq. */
183 spinlock_t outvq_lock;
184
1c85bf35
AS
185 /* The IO vqs for this port */
186 struct virtqueue *in_vq, *out_vq;
187
d99393ef
AS
188 /* File in the debugfs directory that exposes this port's information */
189 struct dentry *debugfs_file;
190
17e5b4f2
AS
191 /*
192 * Keep count of the bytes sent, received and discarded for
193 * this port for accounting and debugging purposes. These
194 * counts are not reset across port open / close events.
195 */
196 struct port_stats stats;
197
4f23c573
AS
198 /*
199 * The entries in this struct will be valid if this port is
200 * hooked up to an hvc console
201 */
202 struct console cons;
17634ba2 203
fb08bd27 204 /* Each port associates with a separate char device */
d22a6989 205 struct cdev *cdev;
fb08bd27
AS
206 struct device *dev;
207
b353a6b8
AS
208 /* Reference-counting to handle port hot-unplugs and file operations */
209 struct kref kref;
210
2030fa49
AS
211 /* A waitqueue for poll() or blocking read operations */
212 wait_queue_head_t waitqueue;
213
431edb8a
AS
214 /* The 'name' of the port that we expose via sysfs properties */
215 char *name;
216
3eae0ade
AS
217 /* We can notify apps of host connect / disconnect events via SIGIO */
218 struct fasync_struct *async_queue;
219
17634ba2
AS
220 /* The 'id' to identify the port with the Host */
221 u32 id;
2030fa49 222
cdfadfc1
AS
223 bool outvq_full;
224
2030fa49
AS
225 /* Is the host device open */
226 bool host_connected;
3c7969cc
AS
227
228 /* We should allow only one process to open a port */
229 bool guest_connected;
21206ede 230};
31610434 231
971f3390
RR
232/* This is the very early arch-specified put chars function. */
233static int (*early_put_chars)(u32, const char *, int);
234
38edf58d
AS
235static struct port *find_port_by_vtermno(u32 vtermno)
236{
237 struct port *port;
4f23c573 238 struct console *cons;
38edf58d
AS
239 unsigned long flags;
240
241 spin_lock_irqsave(&pdrvdata_lock, flags);
4f23c573
AS
242 list_for_each_entry(cons, &pdrvdata.consoles, list) {
243 if (cons->vtermno == vtermno) {
244 port = container_of(cons, struct port, cons);
38edf58d 245 goto out;
4f23c573 246 }
38edf58d
AS
247 }
248 port = NULL;
249out:
250 spin_unlock_irqrestore(&pdrvdata_lock, flags);
251 return port;
252}
253
04950cdf
AS
254static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev,
255 dev_t dev)
256{
257 struct port *port;
258 unsigned long flags;
259
260 spin_lock_irqsave(&portdev->ports_lock, flags);
261 list_for_each_entry(port, &portdev->ports, list)
d22a6989 262 if (port->cdev->dev == dev)
04950cdf
AS
263 goto out;
264 port = NULL;
265out:
266 spin_unlock_irqrestore(&portdev->ports_lock, flags);
267
268 return port;
269}
270
271static struct port *find_port_by_devt(dev_t dev)
272{
273 struct ports_device *portdev;
274 struct port *port;
275 unsigned long flags;
276
277 spin_lock_irqsave(&pdrvdata_lock, flags);
278 list_for_each_entry(portdev, &pdrvdata.portdevs, list) {
279 port = find_port_by_devt_in_portdev(portdev, dev);
280 if (port)
281 goto out;
282 }
283 port = NULL;
284out:
285 spin_unlock_irqrestore(&pdrvdata_lock, flags);
286 return port;
287}
288
17634ba2
AS
289static struct port *find_port_by_id(struct ports_device *portdev, u32 id)
290{
291 struct port *port;
292 unsigned long flags;
293
294 spin_lock_irqsave(&portdev->ports_lock, flags);
295 list_for_each_entry(port, &portdev->ports, list)
296 if (port->id == id)
297 goto out;
298 port = NULL;
299out:
300 spin_unlock_irqrestore(&portdev->ports_lock, flags);
301
302 return port;
303}
304
203baab8
AS
305static struct port *find_port_by_vq(struct ports_device *portdev,
306 struct virtqueue *vq)
307{
308 struct port *port;
203baab8
AS
309 unsigned long flags;
310
17634ba2
AS
311 spin_lock_irqsave(&portdev->ports_lock, flags);
312 list_for_each_entry(port, &portdev->ports, list)
203baab8
AS
313 if (port->in_vq == vq || port->out_vq == vq)
314 goto out;
203baab8
AS
315 port = NULL;
316out:
17634ba2 317 spin_unlock_irqrestore(&portdev->ports_lock, flags);
203baab8
AS
318 return port;
319}
320
17634ba2
AS
321static bool is_console_port(struct port *port)
322{
323 if (port->cons.hvc)
324 return true;
325 return false;
326}
327
328static inline bool use_multiport(struct ports_device *portdev)
329{
330 /*
331 * This condition can be true when put_chars is called from
332 * early_init
333 */
334 if (!portdev->vdev)
335 return 0;
336 return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
337}
338
fdb9a054
AS
339static void free_buf(struct port_buffer *buf)
340{
341 kfree(buf->buf);
342 kfree(buf);
343}
344
345static struct port_buffer *alloc_buf(size_t buf_size)
346{
347 struct port_buffer *buf;
348
349 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
350 if (!buf)
351 goto fail;
352 buf->buf = kzalloc(buf_size, GFP_KERNEL);
353 if (!buf->buf)
354 goto free_buf;
355 buf->len = 0;
356 buf->offset = 0;
357 buf->size = buf_size;
358 return buf;
359
360free_buf:
361 kfree(buf);
362fail:
363 return NULL;
364}
365
a3cde449 366/* Callers should take appropriate locks */
defde669 367static struct port_buffer *get_inbuf(struct port *port)
a3cde449
AS
368{
369 struct port_buffer *buf;
a3cde449
AS
370 unsigned int len;
371
d25a9dda
AS
372 if (port->inbuf)
373 return port->inbuf;
374
375 buf = virtqueue_get_buf(port->in_vq, &len);
a3cde449
AS
376 if (buf) {
377 buf->len = len;
378 buf->offset = 0;
17e5b4f2 379 port->stats.bytes_received += len;
a3cde449
AS
380 }
381 return buf;
382}
383
e27b5198
AS
384/*
385 * Create a scatter-gather list representing our input buffer and put
386 * it in the queue.
387 *
388 * Callers should take appropriate locks.
389 */
203baab8 390static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
e27b5198
AS
391{
392 struct scatterlist sg[1];
203baab8 393 int ret;
1c85bf35 394
e27b5198
AS
395 sg_init_one(sg, buf->buf, buf->size);
396
f96fde41 397 ret = virtqueue_add_buf(vq, sg, 0, 1, buf, GFP_ATOMIC);
505b0451 398 virtqueue_kick(vq);
49e86f16
AS
399 if (!ret)
400 ret = vq->num_free;
203baab8
AS
401 return ret;
402}
403
88f251ac
AS
404/* Discard any unread data this port has. Callers lockers. */
405static void discard_port_data(struct port *port)
406{
407 struct port_buffer *buf;
2d24cdaa 408 unsigned int err;
88f251ac 409
d7a62cd0
AS
410 if (!port->portdev) {
411 /* Device has been unplugged. vqs are already gone. */
412 return;
413 }
2d24cdaa 414 buf = get_inbuf(port);
88f251ac 415
ce072a0c 416 err = 0;
d6933561 417 while (buf) {
17e5b4f2 418 port->stats.bytes_discarded += buf->len - buf->offset;
2d24cdaa 419 if (add_inbuf(port->in_vq, buf) < 0) {
ce072a0c 420 err++;
d6933561
AS
421 free_buf(buf);
422 }
2d24cdaa
AS
423 port->inbuf = NULL;
424 buf = get_inbuf(port);
88f251ac 425 }
ce072a0c 426 if (err)
d6933561 427 dev_warn(port->dev, "Errors adding %d buffers back to vq\n",
ce072a0c 428 err);
88f251ac
AS
429}
430
203baab8
AS
431static bool port_has_data(struct port *port)
432{
433 unsigned long flags;
434 bool ret;
435
d25a9dda 436 ret = false;
203baab8 437 spin_lock_irqsave(&port->inbuf_lock, flags);
d6933561 438 port->inbuf = get_inbuf(port);
d25a9dda 439 if (port->inbuf)
d6933561 440 ret = true;
d25a9dda 441
203baab8 442 spin_unlock_irqrestore(&port->inbuf_lock, flags);
203baab8
AS
443 return ret;
444}
445
3425e706
AS
446static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
447 unsigned int event, unsigned int value)
17634ba2
AS
448{
449 struct scatterlist sg[1];
450 struct virtio_console_control cpkt;
451 struct virtqueue *vq;
604b2ad7 452 unsigned int len;
17634ba2 453
3425e706 454 if (!use_multiport(portdev))
17634ba2
AS
455 return 0;
456
3425e706 457 cpkt.id = port_id;
17634ba2
AS
458 cpkt.event = event;
459 cpkt.value = value;
460
3425e706 461 vq = portdev->c_ovq;
17634ba2
AS
462
463 sg_init_one(sg, &cpkt, sizeof(cpkt));
589575a2 464 if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) == 0) {
505b0451
MT
465 virtqueue_kick(vq);
466 while (!virtqueue_get_buf(vq, &len))
17634ba2
AS
467 cpu_relax();
468 }
469 return 0;
470}
471
3425e706
AS
472static ssize_t send_control_msg(struct port *port, unsigned int event,
473 unsigned int value)
474{
84ec06c5
AS
475 /* Did the port get unplugged before userspace closed it? */
476 if (port->portdev)
477 return __send_control_msg(port->portdev, port->id, event, value);
478 return 0;
3425e706
AS
479}
480
eb5e89fc
MH
481struct buffer_token {
482 union {
483 void *buf;
484 struct scatterlist *sg;
485 } u;
8ca84a50
MH
486 /* If sgpages == 0 then buf is used, else sg is used */
487 unsigned int sgpages;
eb5e89fc
MH
488};
489
8ca84a50 490static void reclaim_sg_pages(struct scatterlist *sg, unsigned int nrpages)
eb5e89fc
MH
491{
492 int i;
493 struct page *page;
494
8ca84a50 495 for (i = 0; i < nrpages; i++) {
eb5e89fc
MH
496 page = sg_page(&sg[i]);
497 if (!page)
498 break;
499 put_page(page);
500 }
501 kfree(sg);
502}
503
cdfadfc1
AS
504/* Callers must take the port->outvq_lock */
505static void reclaim_consumed_buffers(struct port *port)
506{
eb5e89fc 507 struct buffer_token *tok;
cdfadfc1
AS
508 unsigned int len;
509
d7a62cd0
AS
510 if (!port->portdev) {
511 /* Device has been unplugged. vqs are already gone. */
512 return;
513 }
eb5e89fc
MH
514 while ((tok = virtqueue_get_buf(port->out_vq, &len))) {
515 if (tok->sgpages)
8ca84a50 516 reclaim_sg_pages(tok->u.sg, tok->sgpages);
eb5e89fc
MH
517 else
518 kfree(tok->u.buf);
519 kfree(tok);
cdfadfc1
AS
520 port->outvq_full = false;
521 }
522}
523
eb5e89fc
MH
524static ssize_t __send_to_port(struct port *port, struct scatterlist *sg,
525 int nents, size_t in_count,
526 struct buffer_token *tok, bool nonblock)
f997f00b 527{
f997f00b 528 struct virtqueue *out_vq;
589575a2 529 int err;
cdfadfc1 530 unsigned long flags;
f997f00b
AS
531 unsigned int len;
532
533 out_vq = port->out_vq;
534
cdfadfc1
AS
535 spin_lock_irqsave(&port->outvq_lock, flags);
536
537 reclaim_consumed_buffers(port);
538
589575a2 539 err = virtqueue_add_buf(out_vq, sg, nents, 0, tok, GFP_ATOMIC);
f997f00b
AS
540
541 /* Tell Host to go! */
505b0451 542 virtqueue_kick(out_vq);
f997f00b 543
589575a2 544 if (err) {
9ff4cfab 545 in_count = 0;
cdfadfc1 546 goto done;
f997f00b
AS
547 }
548
589575a2 549 if (out_vq->num_free == 0)
cdfadfc1
AS
550 port->outvq_full = true;
551
552 if (nonblock)
553 goto done;
554
555 /*
556 * Wait till the host acknowledges it pushed out the data we
531295e6
AS
557 * sent. This is done for data from the hvc_console; the tty
558 * operations are performed with spinlocks held so we can't
559 * sleep here. An alternative would be to copy the data to a
560 * buffer and relax the spinning requirement. The downside is
561 * we need to kmalloc a GFP_ATOMIC buffer each time the
562 * console driver writes something out.
cdfadfc1 563 */
505b0451 564 while (!virtqueue_get_buf(out_vq, &len))
f997f00b 565 cpu_relax();
cdfadfc1
AS
566done:
567 spin_unlock_irqrestore(&port->outvq_lock, flags);
17e5b4f2
AS
568
569 port->stats.bytes_sent += in_count;
cdfadfc1
AS
570 /*
571 * We're expected to return the amount of data we wrote -- all
572 * of it
573 */
9ff4cfab 574 return in_count;
f997f00b
AS
575}
576
eb5e89fc
MH
577static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
578 bool nonblock)
579{
580 struct scatterlist sg[1];
581 struct buffer_token *tok;
582
583 tok = kmalloc(sizeof(*tok), GFP_ATOMIC);
584 if (!tok)
585 return -ENOMEM;
8ca84a50 586 tok->sgpages = 0;
eb5e89fc
MH
587 tok->u.buf = in_buf;
588
589 sg_init_one(sg, in_buf, in_count);
590
591 return __send_to_port(port, sg, 1, in_count, tok, nonblock);
592}
593
594static ssize_t send_pages(struct port *port, struct scatterlist *sg, int nents,
595 size_t in_count, bool nonblock)
596{
597 struct buffer_token *tok;
598
599 tok = kmalloc(sizeof(*tok), GFP_ATOMIC);
600 if (!tok)
601 return -ENOMEM;
8ca84a50 602 tok->sgpages = nents;
eb5e89fc
MH
603 tok->u.sg = sg;
604
605 return __send_to_port(port, sg, nents, in_count, tok, nonblock);
606}
607
203baab8
AS
608/*
609 * Give out the data that's requested from the buffer that we have
610 * queued up.
611 */
b766ceed
AS
612static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count,
613 bool to_user)
203baab8
AS
614{
615 struct port_buffer *buf;
616 unsigned long flags;
617
618 if (!out_count || !port_has_data(port))
619 return 0;
620
621 buf = port->inbuf;
b766ceed 622 out_count = min(out_count, buf->len - buf->offset);
203baab8 623
b766ceed
AS
624 if (to_user) {
625 ssize_t ret;
626
627 ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count);
628 if (ret)
629 return -EFAULT;
630 } else {
631 memcpy(out_buf, buf->buf + buf->offset, out_count);
632 }
203baab8 633
203baab8
AS
634 buf->offset += out_count;
635
636 if (buf->offset == buf->len) {
637 /*
638 * We're done using all the data in this buffer.
639 * Re-queue so that the Host can send us more data.
640 */
641 spin_lock_irqsave(&port->inbuf_lock, flags);
642 port->inbuf = NULL;
643
644 if (add_inbuf(port->in_vq, buf) < 0)
fb08bd27 645 dev_warn(port->dev, "failed add_buf\n");
203baab8
AS
646
647 spin_unlock_irqrestore(&port->inbuf_lock, flags);
648 }
b766ceed 649 /* Return the number of bytes actually copied */
203baab8 650 return out_count;
e27b5198
AS
651}
652
2030fa49 653/* The condition that must be true for polling to end */
60caacd3 654static bool will_read_block(struct port *port)
2030fa49 655{
3709ea7a
AS
656 if (!port->guest_connected) {
657 /* Port got hot-unplugged. Let's exit. */
658 return false;
659 }
60caacd3 660 return !port_has_data(port) && port->host_connected;
2030fa49
AS
661}
662
cdfadfc1
AS
663static bool will_write_block(struct port *port)
664{
665 bool ret;
666
60e5e0b8
AS
667 if (!port->guest_connected) {
668 /* Port got hot-unplugged. Let's exit. */
669 return false;
670 }
cdfadfc1
AS
671 if (!port->host_connected)
672 return true;
673
674 spin_lock_irq(&port->outvq_lock);
675 /*
676 * Check if the Host has consumed any buffers since we last
677 * sent data (this is only applicable for nonblocking ports).
678 */
679 reclaim_consumed_buffers(port);
680 ret = port->outvq_full;
681 spin_unlock_irq(&port->outvq_lock);
682
683 return ret;
684}
685
2030fa49
AS
686static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
687 size_t count, loff_t *offp)
688{
689 struct port *port;
690 ssize_t ret;
691
692 port = filp->private_data;
693
694 if (!port_has_data(port)) {
695 /*
696 * If nothing's connected on the host just return 0 in
697 * case of list_empty; this tells the userspace app
698 * that there's no connection
699 */
700 if (!port->host_connected)
701 return 0;
702 if (filp->f_flags & O_NONBLOCK)
703 return -EAGAIN;
704
a08fa92d
AS
705 ret = wait_event_freezable(port->waitqueue,
706 !will_read_block(port));
2030fa49
AS
707 if (ret < 0)
708 return ret;
709 }
b3dddb9e
AS
710 /* Port got hot-unplugged. */
711 if (!port->guest_connected)
712 return -ENODEV;
2030fa49
AS
713 /*
714 * We could've received a disconnection message while we were
715 * waiting for more data.
716 *
717 * This check is not clubbed in the if() statement above as we
718 * might receive some data as well as the host could get
719 * disconnected after we got woken up from our wait. So we
720 * really want to give off whatever data we have and only then
721 * check for host_connected.
722 */
723 if (!port_has_data(port) && !port->host_connected)
724 return 0;
725
726 return fill_readbuf(port, ubuf, count, true);
727}
728
efe75d24
MH
729static int wait_port_writable(struct port *port, bool nonblock)
730{
731 int ret;
732
733 if (will_write_block(port)) {
734 if (nonblock)
735 return -EAGAIN;
736
737 ret = wait_event_freezable(port->waitqueue,
738 !will_write_block(port));
739 if (ret < 0)
740 return ret;
741 }
742 /* Port got hot-unplugged. */
743 if (!port->guest_connected)
744 return -ENODEV;
745
746 return 0;
747}
748
2030fa49
AS
749static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
750 size_t count, loff_t *offp)
751{
752 struct port *port;
753 char *buf;
754 ssize_t ret;
cdfadfc1 755 bool nonblock;
2030fa49 756
65745422
AS
757 /* Userspace could be out to fool us */
758 if (!count)
759 return 0;
760
2030fa49
AS
761 port = filp->private_data;
762
cdfadfc1
AS
763 nonblock = filp->f_flags & O_NONBLOCK;
764
efe75d24
MH
765 ret = wait_port_writable(port, nonblock);
766 if (ret < 0)
767 return ret;
cdfadfc1 768
2030fa49
AS
769 count = min((size_t)(32 * 1024), count);
770
771 buf = kmalloc(count, GFP_KERNEL);
772 if (!buf)
773 return -ENOMEM;
774
775 ret = copy_from_user(buf, ubuf, count);
776 if (ret) {
777 ret = -EFAULT;
778 goto free_buf;
779 }
780
531295e6
AS
781 /*
782 * We now ask send_buf() to not spin for generic ports -- we
783 * can re-use the same code path that non-blocking file
784 * descriptors take for blocking file descriptors since the
785 * wait is already done and we're certain the write will go
786 * through to the host.
787 */
788 nonblock = true;
cdfadfc1
AS
789 ret = send_buf(port, buf, count, nonblock);
790
791 if (nonblock && ret > 0)
792 goto out;
793
2030fa49
AS
794free_buf:
795 kfree(buf);
cdfadfc1 796out:
2030fa49
AS
797 return ret;
798}
799
eb5e89fc
MH
800struct sg_list {
801 unsigned int n;
8ca84a50 802 unsigned int size;
eb5e89fc
MH
803 size_t len;
804 struct scatterlist *sg;
805};
806
807static int pipe_to_sg(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
808 struct splice_desc *sd)
809{
810 struct sg_list *sgl = sd->u.data;
ec8fc870 811 unsigned int offset, len;
eb5e89fc 812
8ca84a50 813 if (sgl->n == sgl->size)
eb5e89fc
MH
814 return 0;
815
816 /* Try lock this page */
817 if (buf->ops->steal(pipe, buf) == 0) {
818 /* Get reference and unlock page for moving */
819 get_page(buf->page);
820 unlock_page(buf->page);
821
822 len = min(buf->len, sd->len);
823 sg_set_page(&(sgl->sg[sgl->n]), buf->page, len, buf->offset);
ec8fc870
MH
824 } else {
825 /* Failback to copying a page */
826 struct page *page = alloc_page(GFP_KERNEL);
827 char *src = buf->ops->map(pipe, buf, 1);
828 char *dst;
829
830 if (!page)
831 return -ENOMEM;
832 dst = kmap(page);
833
834 offset = sd->pos & ~PAGE_MASK;
835
836 len = sd->len;
837 if (len + offset > PAGE_SIZE)
838 len = PAGE_SIZE - offset;
839
840 memcpy(dst + offset, src + buf->offset, len);
841
842 kunmap(page);
843 buf->ops->unmap(pipe, buf, src);
844
845 sg_set_page(&(sgl->sg[sgl->n]), page, len, offset);
eb5e89fc 846 }
ec8fc870
MH
847 sgl->n++;
848 sgl->len += len;
eb5e89fc
MH
849
850 return len;
851}
852
853/* Faster zero-copy write by splicing */
854static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe,
855 struct file *filp, loff_t *ppos,
856 size_t len, unsigned int flags)
857{
858 struct port *port = filp->private_data;
859 struct sg_list sgl;
860 ssize_t ret;
861 struct splice_desc sd = {
862 .total_len = len,
863 .flags = flags,
864 .pos = *ppos,
865 .u.data = &sgl,
866 };
867
efe75d24
MH
868 ret = wait_port_writable(port, filp->f_flags & O_NONBLOCK);
869 if (ret < 0)
870 return ret;
871
eb5e89fc
MH
872 sgl.n = 0;
873 sgl.len = 0;
8ca84a50
MH
874 sgl.size = pipe->nrbufs;
875 sgl.sg = kmalloc(sizeof(struct scatterlist) * sgl.size, GFP_KERNEL);
eb5e89fc
MH
876 if (unlikely(!sgl.sg))
877 return -ENOMEM;
878
8ca84a50 879 sg_init_table(sgl.sg, sgl.size);
eb5e89fc
MH
880 ret = __splice_from_pipe(pipe, &sd, pipe_to_sg);
881 if (likely(ret > 0))
882 ret = send_pages(port, sgl.sg, sgl.n, sgl.len, true);
883
884 return ret;
885}
886
2030fa49
AS
887static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
888{
889 struct port *port;
890 unsigned int ret;
891
892 port = filp->private_data;
893 poll_wait(filp, &port->waitqueue, wait);
894
8529a504
AS
895 if (!port->guest_connected) {
896 /* Port got unplugged */
897 return POLLHUP;
898 }
2030fa49 899 ret = 0;
6df7aadc 900 if (!will_read_block(port))
2030fa49 901 ret |= POLLIN | POLLRDNORM;
cdfadfc1 902 if (!will_write_block(port))
2030fa49
AS
903 ret |= POLLOUT;
904 if (!port->host_connected)
905 ret |= POLLHUP;
906
907 return ret;
908}
909
b353a6b8
AS
910static void remove_port(struct kref *kref);
911
2030fa49
AS
912static int port_fops_release(struct inode *inode, struct file *filp)
913{
914 struct port *port;
915
916 port = filp->private_data;
917
918 /* Notify host of port being closed */
919 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
920
88f251ac 921 spin_lock_irq(&port->inbuf_lock);
3c7969cc
AS
922 port->guest_connected = false;
923
88f251ac
AS
924 discard_port_data(port);
925
926 spin_unlock_irq(&port->inbuf_lock);
927
cdfadfc1
AS
928 spin_lock_irq(&port->outvq_lock);
929 reclaim_consumed_buffers(port);
930 spin_unlock_irq(&port->outvq_lock);
931
b353a6b8
AS
932 /*
933 * Locks aren't necessary here as a port can't be opened after
934 * unplug, and if a port isn't unplugged, a kref would already
935 * exist for the port. Plus, taking ports_lock here would
936 * create a dependency on other locks taken by functions
937 * inside remove_port if we're the last holder of the port,
938 * creating many problems.
939 */
940 kref_put(&port->kref, remove_port);
941
2030fa49
AS
942 return 0;
943}
944
945static int port_fops_open(struct inode *inode, struct file *filp)
946{
947 struct cdev *cdev = inode->i_cdev;
948 struct port *port;
8ad37e83 949 int ret;
2030fa49 950
04950cdf 951 port = find_port_by_devt(cdev->dev);
2030fa49
AS
952 filp->private_data = port;
953
b353a6b8
AS
954 /* Prevent against a port getting hot-unplugged at the same time */
955 spin_lock_irq(&port->portdev->ports_lock);
956 kref_get(&port->kref);
957 spin_unlock_irq(&port->portdev->ports_lock);
958
2030fa49
AS
959 /*
960 * Don't allow opening of console port devices -- that's done
961 * via /dev/hvc
962 */
8ad37e83
AS
963 if (is_console_port(port)) {
964 ret = -ENXIO;
965 goto out;
966 }
2030fa49 967
3c7969cc
AS
968 /* Allow only one process to open a particular port at a time */
969 spin_lock_irq(&port->inbuf_lock);
970 if (port->guest_connected) {
971 spin_unlock_irq(&port->inbuf_lock);
8ad37e83
AS
972 ret = -EMFILE;
973 goto out;
3c7969cc
AS
974 }
975
976 port->guest_connected = true;
977 spin_unlock_irq(&port->inbuf_lock);
978
cdfadfc1
AS
979 spin_lock_irq(&port->outvq_lock);
980 /*
981 * There might be a chance that we missed reclaiming a few
982 * buffers in the window of the port getting previously closed
983 * and opening now.
984 */
985 reclaim_consumed_buffers(port);
986 spin_unlock_irq(&port->outvq_lock);
987
299fb61c
AS
988 nonseekable_open(inode, filp);
989
2030fa49
AS
990 /* Notify host of port being opened */
991 send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1);
992
993 return 0;
8ad37e83 994out:
b353a6b8 995 kref_put(&port->kref, remove_port);
8ad37e83 996 return ret;
2030fa49
AS
997}
998
3eae0ade
AS
999static int port_fops_fasync(int fd, struct file *filp, int mode)
1000{
1001 struct port *port;
1002
1003 port = filp->private_data;
1004 return fasync_helper(fd, filp, mode, &port->async_queue);
1005}
1006
2030fa49
AS
1007/*
1008 * The file operations that we support: programs in the guest can open
1009 * a console device, read from it, write to it, poll for data and
1010 * close it. The devices are at
1011 * /dev/vport<device number>p<port number>
1012 */
1013static const struct file_operations port_fops = {
1014 .owner = THIS_MODULE,
1015 .open = port_fops_open,
1016 .read = port_fops_read,
1017 .write = port_fops_write,
eb5e89fc 1018 .splice_write = port_fops_splice_write,
2030fa49
AS
1019 .poll = port_fops_poll,
1020 .release = port_fops_release,
3eae0ade 1021 .fasync = port_fops_fasync,
299fb61c 1022 .llseek = no_llseek,
2030fa49
AS
1023};
1024
a23ea924
RR
1025/*
1026 * The put_chars() callback is pretty straightforward.
31610434 1027 *
a23ea924
RR
1028 * We turn the characters into a scatter-gather list, add it to the
1029 * output queue and then kick the Host. Then we sit here waiting for
1030 * it to finish: inefficient in theory, but in practice
1031 * implementations will do it immediately (lguest's Launcher does).
1032 */
31610434
RR
1033static int put_chars(u32 vtermno, const char *buf, int count)
1034{
21206ede 1035 struct port *port;
38edf58d 1036
162a689a
FD
1037 if (unlikely(early_put_chars))
1038 return early_put_chars(vtermno, buf, count);
1039
38edf58d
AS
1040 port = find_port_by_vtermno(vtermno);
1041 if (!port)
6dc69f97 1042 return -EPIPE;
31610434 1043
cdfadfc1 1044 return send_buf(port, (void *)buf, count, false);
31610434
RR
1045}
1046
a23ea924
RR
1047/*
1048 * get_chars() is the callback from the hvc_console infrastructure
1049 * when an interrupt is received.
31610434 1050 *
203baab8
AS
1051 * We call out to fill_readbuf that gets us the required data from the
1052 * buffers that are queued up.
a23ea924 1053 */
31610434
RR
1054static int get_chars(u32 vtermno, char *buf, int count)
1055{
21206ede
RR
1056 struct port *port;
1057
6dc69f97
AS
1058 /* If we've not set up the port yet, we have no input to give. */
1059 if (unlikely(early_put_chars))
1060 return 0;
1061
38edf58d
AS
1062 port = find_port_by_vtermno(vtermno);
1063 if (!port)
6dc69f97 1064 return -EPIPE;
21206ede 1065
31610434 1066 /* If we don't have an input queue yet, we can't get input. */
21206ede 1067 BUG_ON(!port->in_vq);
31610434 1068
b766ceed 1069 return fill_readbuf(port, buf, count, false);
31610434 1070}
31610434 1071
cb06e367 1072static void resize_console(struct port *port)
c2983458 1073{
cb06e367 1074 struct virtio_device *vdev;
c2983458 1075
2de16a49 1076 /* The port could have been hot-unplugged */
9778829c 1077 if (!port || !is_console_port(port))
2de16a49
AS
1078 return;
1079
cb06e367 1080 vdev = port->portdev->vdev;
9778829c
AS
1081 if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE))
1082 hvc_resize(port->cons.hvc, port->cons.ws);
c2983458
CB
1083}
1084
38edf58d 1085/* We set the configuration at this point, since we now have a tty */
91fcad19
CB
1086static int notifier_add_vio(struct hvc_struct *hp, int data)
1087{
38edf58d
AS
1088 struct port *port;
1089
1090 port = find_port_by_vtermno(hp->vtermno);
1091 if (!port)
1092 return -EINVAL;
1093
91fcad19 1094 hp->irq_requested = 1;
cb06e367 1095 resize_console(port);
c2983458 1096
91fcad19
CB
1097 return 0;
1098}
1099
1100static void notifier_del_vio(struct hvc_struct *hp, int data)
1101{
1102 hp->irq_requested = 0;
1103}
1104
17634ba2 1105/* The operations for console ports. */
1dff3996 1106static const struct hv_ops hv_ops = {
971f3390
RR
1107 .get_chars = get_chars,
1108 .put_chars = put_chars,
1109 .notifier_add = notifier_add_vio,
1110 .notifier_del = notifier_del_vio,
1111 .notifier_hangup = notifier_del_vio,
1112};
1113
1114/*
1115 * Console drivers are initialized very early so boot messages can go
1116 * out, so we do things slightly differently from the generic virtio
1117 * initialization of the net and block drivers.
1118 *
1119 * At this stage, the console is output-only. It's too early to set
1120 * up a virtqueue, so we let the drivers do some boutique early-output
1121 * thing.
1122 */
1123int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
1124{
1125 early_put_chars = put_chars;
1126 return hvc_instantiate(0, 0, &hv_ops);
1127}
1128
17634ba2 1129int init_port_console(struct port *port)
cfa6d379
AS
1130{
1131 int ret;
1132
1133 /*
1134 * The Host's telling us this port is a console port. Hook it
1135 * up with an hvc console.
1136 *
1137 * To set up and manage our virtual console, we call
1138 * hvc_alloc().
1139 *
1140 * The first argument of hvc_alloc() is the virtual console
1141 * number. The second argument is the parameter for the
1142 * notification mechanism (like irq number). We currently
1143 * leave this as zero, virtqueues have implicit notifications.
1144 *
1145 * The third argument is a "struct hv_ops" containing the
1146 * put_chars() get_chars(), notifier_add() and notifier_del()
1147 * pointers. The final argument is the output buffer size: we
1148 * can do any size, so we put PAGE_SIZE here.
1149 */
1150 port->cons.vtermno = pdrvdata.next_vtermno;
1151
1152 port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE);
1153 if (IS_ERR(port->cons.hvc)) {
1154 ret = PTR_ERR(port->cons.hvc);
298add72
AS
1155 dev_err(port->dev,
1156 "error %d allocating hvc for port\n", ret);
cfa6d379
AS
1157 port->cons.hvc = NULL;
1158 return ret;
1159 }
1160 spin_lock_irq(&pdrvdata_lock);
1161 pdrvdata.next_vtermno++;
1162 list_add_tail(&port->cons.list, &pdrvdata.consoles);
1163 spin_unlock_irq(&pdrvdata_lock);
3c7969cc 1164 port->guest_connected = true;
cfa6d379 1165
1d05160b
AS
1166 /*
1167 * Start using the new console output if this is the first
1168 * console to come up.
1169 */
1170 if (early_put_chars)
1171 early_put_chars = NULL;
1172
2030fa49
AS
1173 /* Notify host of port being opened */
1174 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
1175
cfa6d379
AS
1176 return 0;
1177}
1178
431edb8a
AS
1179static ssize_t show_port_name(struct device *dev,
1180 struct device_attribute *attr, char *buffer)
1181{
1182 struct port *port;
1183
1184 port = dev_get_drvdata(dev);
1185
1186 return sprintf(buffer, "%s\n", port->name);
1187}
1188
1189static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL);
1190
1191static struct attribute *port_sysfs_entries[] = {
1192 &dev_attr_name.attr,
1193 NULL
1194};
1195
1196static struct attribute_group port_attribute_group = {
1197 .name = NULL, /* put in device directory */
1198 .attrs = port_sysfs_entries,
1199};
1200
d99393ef
AS
1201static ssize_t debugfs_read(struct file *filp, char __user *ubuf,
1202 size_t count, loff_t *offp)
1203{
1204 struct port *port;
1205 char *buf;
1206 ssize_t ret, out_offset, out_count;
1207
1208 out_count = 1024;
1209 buf = kmalloc(out_count, GFP_KERNEL);
1210 if (!buf)
1211 return -ENOMEM;
1212
1213 port = filp->private_data;
1214 out_offset = 0;
1215 out_offset += snprintf(buf + out_offset, out_count,
1216 "name: %s\n", port->name ? port->name : "");
1217 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1218 "guest_connected: %d\n", port->guest_connected);
1219 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1220 "host_connected: %d\n", port->host_connected);
cdfadfc1
AS
1221 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1222 "outvq_full: %d\n", port->outvq_full);
17e5b4f2
AS
1223 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1224 "bytes_sent: %lu\n", port->stats.bytes_sent);
1225 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1226 "bytes_received: %lu\n",
1227 port->stats.bytes_received);
1228 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1229 "bytes_discarded: %lu\n",
1230 port->stats.bytes_discarded);
d99393ef
AS
1231 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1232 "is_console: %s\n",
1233 is_console_port(port) ? "yes" : "no");
1234 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1235 "console_vtermno: %u\n", port->cons.vtermno);
1236
1237 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
1238 kfree(buf);
1239 return ret;
1240}
1241
1242static const struct file_operations port_debugfs_ops = {
1243 .owner = THIS_MODULE,
234e3405 1244 .open = simple_open,
d99393ef
AS
1245 .read = debugfs_read,
1246};
1247
9778829c
AS
1248static void set_console_size(struct port *port, u16 rows, u16 cols)
1249{
1250 if (!port || !is_console_port(port))
1251 return;
1252
1253 port->cons.ws.ws_row = rows;
1254 port->cons.ws.ws_col = cols;
1255}
1256
c446f8fc
AS
1257static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
1258{
1259 struct port_buffer *buf;
1260 unsigned int nr_added_bufs;
1261 int ret;
1262
1263 nr_added_bufs = 0;
1264 do {
1265 buf = alloc_buf(PAGE_SIZE);
1266 if (!buf)
1267 break;
1268
1269 spin_lock_irq(lock);
1270 ret = add_inbuf(vq, buf);
1271 if (ret < 0) {
1272 spin_unlock_irq(lock);
1273 free_buf(buf);
1274 break;
1275 }
1276 nr_added_bufs++;
1277 spin_unlock_irq(lock);
1278 } while (ret > 0);
1279
1280 return nr_added_bufs;
1281}
1282
3eae0ade
AS
1283static void send_sigio_to_port(struct port *port)
1284{
1285 if (port->async_queue && port->guest_connected)
1286 kill_fasync(&port->async_queue, SIGIO, POLL_OUT);
1287}
1288
c446f8fc
AS
1289static int add_port(struct ports_device *portdev, u32 id)
1290{
1291 char debugfs_name[16];
1292 struct port *port;
1293 struct port_buffer *buf;
1294 dev_t devt;
1295 unsigned int nr_added_bufs;
1296 int err;
1297
1298 port = kmalloc(sizeof(*port), GFP_KERNEL);
1299 if (!port) {
1300 err = -ENOMEM;
1301 goto fail;
1302 }
b353a6b8 1303 kref_init(&port->kref);
c446f8fc
AS
1304
1305 port->portdev = portdev;
1306 port->id = id;
1307
1308 port->name = NULL;
1309 port->inbuf = NULL;
1310 port->cons.hvc = NULL;
3eae0ade 1311 port->async_queue = NULL;
c446f8fc 1312
9778829c
AS
1313 port->cons.ws.ws_row = port->cons.ws.ws_col = 0;
1314
c446f8fc 1315 port->host_connected = port->guest_connected = false;
17e5b4f2 1316 port->stats = (struct port_stats) { 0 };
c446f8fc 1317
cdfadfc1
AS
1318 port->outvq_full = false;
1319
c446f8fc
AS
1320 port->in_vq = portdev->in_vqs[port->id];
1321 port->out_vq = portdev->out_vqs[port->id];
1322
d22a6989
AS
1323 port->cdev = cdev_alloc();
1324 if (!port->cdev) {
1325 dev_err(&port->portdev->vdev->dev, "Error allocating cdev\n");
1326 err = -ENOMEM;
1327 goto free_port;
1328 }
1329 port->cdev->ops = &port_fops;
c446f8fc
AS
1330
1331 devt = MKDEV(portdev->chr_major, id);
d22a6989 1332 err = cdev_add(port->cdev, devt, 1);
c446f8fc
AS
1333 if (err < 0) {
1334 dev_err(&port->portdev->vdev->dev,
1335 "Error %d adding cdev for port %u\n", err, id);
d22a6989 1336 goto free_cdev;
c446f8fc
AS
1337 }
1338 port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
1339 devt, port, "vport%up%u",
1340 port->portdev->drv_index, id);
1341 if (IS_ERR(port->dev)) {
1342 err = PTR_ERR(port->dev);
1343 dev_err(&port->portdev->vdev->dev,
1344 "Error %d creating device for port %u\n",
1345 err, id);
1346 goto free_cdev;
1347 }
1348
1349 spin_lock_init(&port->inbuf_lock);
cdfadfc1 1350 spin_lock_init(&port->outvq_lock);
c446f8fc
AS
1351 init_waitqueue_head(&port->waitqueue);
1352
1353 /* Fill the in_vq with buffers so the host can send us data. */
1354 nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock);
1355 if (!nr_added_bufs) {
1356 dev_err(port->dev, "Error allocating inbufs\n");
1357 err = -ENOMEM;
1358 goto free_device;
1359 }
1360
1361 /*
1362 * If we're not using multiport support, this has to be a console port
1363 */
1364 if (!use_multiport(port->portdev)) {
1365 err = init_port_console(port);
1366 if (err)
1367 goto free_inbufs;
1368 }
1369
1370 spin_lock_irq(&portdev->ports_lock);
1371 list_add_tail(&port->list, &port->portdev->ports);
1372 spin_unlock_irq(&portdev->ports_lock);
1373
1374 /*
1375 * Tell the Host we're set so that it can send us various
1376 * configuration parameters for this port (eg, port name,
1377 * caching, whether this is a console port, etc.)
1378 */
1379 send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
1380
1381 if (pdrvdata.debugfs_dir) {
1382 /*
1383 * Finally, create the debugfs file that we can use to
1384 * inspect a port's state at any time
1385 */
1386 sprintf(debugfs_name, "vport%up%u",
1387 port->portdev->drv_index, id);
1388 port->debugfs_file = debugfs_create_file(debugfs_name, 0444,
1389 pdrvdata.debugfs_dir,
1390 port,
1391 &port_debugfs_ops);
1392 }
1393 return 0;
1394
1395free_inbufs:
1396 while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
1397 free_buf(buf);
1398free_device:
1399 device_destroy(pdrvdata.class, port->dev->devt);
1400free_cdev:
d22a6989 1401 cdev_del(port->cdev);
c446f8fc
AS
1402free_port:
1403 kfree(port);
1404fail:
1405 /* The host might want to notify management sw about port add failure */
0643e4c6 1406 __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0);
c446f8fc
AS
1407 return err;
1408}
1409
b353a6b8
AS
1410/* No users remain, remove all port-specific data. */
1411static void remove_port(struct kref *kref)
1412{
1413 struct port *port;
1414
1415 port = container_of(kref, struct port, kref);
1416
1417 sysfs_remove_group(&port->dev->kobj, &port_attribute_group);
1418 device_destroy(pdrvdata.class, port->dev->devt);
1419 cdev_del(port->cdev);
1420
1421 kfree(port->name);
1422
1423 debugfs_remove(port->debugfs_file);
1424
1425 kfree(port);
1426}
1427
a0e2dbfc
AS
1428static void remove_port_data(struct port *port)
1429{
1430 struct port_buffer *buf;
1431
1432 /* Remove unused data this port might have received. */
1433 discard_port_data(port);
1434
1435 reclaim_consumed_buffers(port);
1436
1437 /* Remove buffers we queued up for the Host to send us data in. */
1438 while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
1439 free_buf(buf);
1440}
1441
b353a6b8
AS
1442/*
1443 * Port got unplugged. Remove port from portdev's list and drop the
1444 * kref reference. If no userspace has this port opened, it will
1445 * result in immediate removal the port.
1446 */
1447static void unplug_port(struct port *port)
1f7aa42d 1448{
b353a6b8
AS
1449 spin_lock_irq(&port->portdev->ports_lock);
1450 list_del(&port->list);
1451 spin_unlock_irq(&port->portdev->ports_lock);
1452
0047634d
AS
1453 if (port->guest_connected) {
1454 port->guest_connected = false;
1455 port->host_connected = false;
1456 wake_up_interruptible(&port->waitqueue);
a461e11e
AS
1457
1458 /* Let the app know the port is going down. */
1459 send_sigio_to_port(port);
0047634d
AS
1460 }
1461
1f7aa42d
AS
1462 if (is_console_port(port)) {
1463 spin_lock_irq(&pdrvdata_lock);
1464 list_del(&port->cons.list);
1465 spin_unlock_irq(&pdrvdata_lock);
1466 hvc_remove(port->cons.hvc);
1467 }
1f7aa42d 1468
a0e2dbfc 1469 remove_port_data(port);
a9cdd485 1470
b353a6b8
AS
1471 /*
1472 * We should just assume the device itself has gone off --
1473 * else a close on an open port later will try to send out a
1474 * control message.
1475 */
1476 port->portdev = NULL;
d99393ef 1477
b353a6b8
AS
1478 /*
1479 * Locks around here are not necessary - a port can't be
1480 * opened after we removed the port struct from ports_list
1481 * above.
1482 */
1483 kref_put(&port->kref, remove_port);
1f7aa42d
AS
1484}
1485
17634ba2
AS
1486/* Any private messages that the Host and Guest want to share */
1487static void handle_control_message(struct ports_device *portdev,
1488 struct port_buffer *buf)
1489{
1490 struct virtio_console_control *cpkt;
1491 struct port *port;
431edb8a
AS
1492 size_t name_size;
1493 int err;
17634ba2
AS
1494
1495 cpkt = (struct virtio_console_control *)(buf->buf + buf->offset);
1496
1497 port = find_port_by_id(portdev, cpkt->id);
f909f850 1498 if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) {
17634ba2
AS
1499 /* No valid header at start of buffer. Drop it. */
1500 dev_dbg(&portdev->vdev->dev,
1501 "Invalid index %u in control packet\n", cpkt->id);
1502 return;
1503 }
1504
1505 switch (cpkt->event) {
f909f850
AS
1506 case VIRTIO_CONSOLE_PORT_ADD:
1507 if (port) {
1d05160b
AS
1508 dev_dbg(&portdev->vdev->dev,
1509 "Port %u already added\n", port->id);
f909f850
AS
1510 send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
1511 break;
1512 }
1513 if (cpkt->id >= portdev->config.max_nr_ports) {
1514 dev_warn(&portdev->vdev->dev,
1515 "Request for adding port with out-of-bound id %u, max. supported id: %u\n",
1516 cpkt->id, portdev->config.max_nr_ports - 1);
1517 break;
1518 }
1519 add_port(portdev, cpkt->id);
1520 break;
1521 case VIRTIO_CONSOLE_PORT_REMOVE:
b353a6b8 1522 unplug_port(port);
f909f850 1523 break;
17634ba2
AS
1524 case VIRTIO_CONSOLE_CONSOLE_PORT:
1525 if (!cpkt->value)
1526 break;
1527 if (is_console_port(port))
1528 break;
1529
1530 init_port_console(port);
5e38483b 1531 complete(&early_console_added);
17634ba2
AS
1532 /*
1533 * Could remove the port here in case init fails - but
1534 * have to notify the host first.
1535 */
1536 break;
8345adbf
AS
1537 case VIRTIO_CONSOLE_RESIZE: {
1538 struct {
1539 __u16 rows;
1540 __u16 cols;
1541 } size;
1542
17634ba2
AS
1543 if (!is_console_port(port))
1544 break;
8345adbf
AS
1545
1546 memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt),
1547 sizeof(size));
1548 set_console_size(port, size.rows, size.cols);
1549
17634ba2
AS
1550 port->cons.hvc->irq_requested = 1;
1551 resize_console(port);
1552 break;
8345adbf 1553 }
2030fa49
AS
1554 case VIRTIO_CONSOLE_PORT_OPEN:
1555 port->host_connected = cpkt->value;
1556 wake_up_interruptible(&port->waitqueue);
cdfadfc1
AS
1557 /*
1558 * If the host port got closed and the host had any
1559 * unconsumed buffers, we'll be able to reclaim them
1560 * now.
1561 */
1562 spin_lock_irq(&port->outvq_lock);
1563 reclaim_consumed_buffers(port);
1564 spin_unlock_irq(&port->outvq_lock);
3eae0ade
AS
1565
1566 /*
1567 * If the guest is connected, it'll be interested in
1568 * knowing the host connection state changed.
1569 */
1570 send_sigio_to_port(port);
2030fa49 1571 break;
431edb8a 1572 case VIRTIO_CONSOLE_PORT_NAME:
291024ef
AS
1573 /*
1574 * If we woke up after hibernation, we can get this
1575 * again. Skip it in that case.
1576 */
1577 if (port->name)
1578 break;
1579
431edb8a
AS
1580 /*
1581 * Skip the size of the header and the cpkt to get the size
1582 * of the name that was sent
1583 */
1584 name_size = buf->len - buf->offset - sizeof(*cpkt) + 1;
1585
1586 port->name = kmalloc(name_size, GFP_KERNEL);
1587 if (!port->name) {
1588 dev_err(port->dev,
1589 "Not enough space to store port name\n");
1590 break;
1591 }
1592 strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt),
1593 name_size - 1);
1594 port->name[name_size - 1] = 0;
1595
1596 /*
1597 * Since we only have one sysfs attribute, 'name',
1598 * create it only if we have a name for the port.
1599 */
1600 err = sysfs_create_group(&port->dev->kobj,
1601 &port_attribute_group);
ec64213c 1602 if (err) {
431edb8a
AS
1603 dev_err(port->dev,
1604 "Error %d creating sysfs device attributes\n",
1605 err);
ec64213c
AS
1606 } else {
1607 /*
1608 * Generate a udev event so that appropriate
1609 * symlinks can be created based on udev
1610 * rules.
1611 */
1612 kobject_uevent(&port->dev->kobj, KOBJ_CHANGE);
1613 }
431edb8a 1614 break;
17634ba2
AS
1615 }
1616}
1617
1618static void control_work_handler(struct work_struct *work)
1619{
1620 struct ports_device *portdev;
1621 struct virtqueue *vq;
1622 struct port_buffer *buf;
1623 unsigned int len;
1624
1625 portdev = container_of(work, struct ports_device, control_work);
1626 vq = portdev->c_ivq;
1627
1628 spin_lock(&portdev->cvq_lock);
505b0451 1629 while ((buf = virtqueue_get_buf(vq, &len))) {
17634ba2
AS
1630 spin_unlock(&portdev->cvq_lock);
1631
1632 buf->len = len;
1633 buf->offset = 0;
1634
1635 handle_control_message(portdev, buf);
1636
1637 spin_lock(&portdev->cvq_lock);
1638 if (add_inbuf(portdev->c_ivq, buf) < 0) {
1639 dev_warn(&portdev->vdev->dev,
1640 "Error adding buffer to queue\n");
1641 free_buf(buf);
1642 }
1643 }
1644 spin_unlock(&portdev->cvq_lock);
1645}
1646
2770c5ea
AS
1647static void out_intr(struct virtqueue *vq)
1648{
1649 struct port *port;
1650
1651 port = find_port_by_vq(vq->vdev->priv, vq);
1652 if (!port)
1653 return;
1654
1655 wake_up_interruptible(&port->waitqueue);
1656}
1657
17634ba2
AS
1658static void in_intr(struct virtqueue *vq)
1659{
1660 struct port *port;
1661 unsigned long flags;
1662
1663 port = find_port_by_vq(vq->vdev->priv, vq);
1664 if (!port)
1665 return;
1666
1667 spin_lock_irqsave(&port->inbuf_lock, flags);
d25a9dda 1668 port->inbuf = get_inbuf(port);
17634ba2 1669
88f251ac
AS
1670 /*
1671 * Don't queue up data when port is closed. This condition
1672 * can be reached when a console port is not yet connected (no
1673 * tty is spawned) and the host sends out data to console
1674 * ports. For generic serial ports, the host won't
1675 * (shouldn't) send data till the guest is connected.
1676 */
1677 if (!port->guest_connected)
1678 discard_port_data(port);
1679
17634ba2
AS
1680 spin_unlock_irqrestore(&port->inbuf_lock, flags);
1681
2030fa49
AS
1682 wake_up_interruptible(&port->waitqueue);
1683
55f6bcce
AS
1684 /* Send a SIGIO indicating new data in case the process asked for it */
1685 send_sigio_to_port(port);
1686
17634ba2
AS
1687 if (is_console_port(port) && hvc_poll(port->cons.hvc))
1688 hvc_kick();
1689}
1690
1691static void control_intr(struct virtqueue *vq)
1692{
1693 struct ports_device *portdev;
1694
1695 portdev = vq->vdev->priv;
1696 schedule_work(&portdev->control_work);
1697}
1698
7f5d810d
AS
1699static void config_intr(struct virtio_device *vdev)
1700{
1701 struct ports_device *portdev;
1702
1703 portdev = vdev->priv;
99f905f8 1704
4038f5b7 1705 if (!use_multiport(portdev)) {
9778829c
AS
1706 struct port *port;
1707 u16 rows, cols;
1708
1709 vdev->config->get(vdev,
1710 offsetof(struct virtio_console_config, cols),
1711 &cols, sizeof(u16));
1712 vdev->config->get(vdev,
1713 offsetof(struct virtio_console_config, rows),
1714 &rows, sizeof(u16));
1715
1716 port = find_port_by_id(portdev, 0);
1717 set_console_size(port, rows, cols);
1718
4038f5b7
AS
1719 /*
1720 * We'll use this way of resizing only for legacy
1721 * support. For newer userspace
1722 * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages
1723 * to indicate console size changes so that it can be
1724 * done per-port.
1725 */
9778829c 1726 resize_console(port);
4038f5b7 1727 }
7f5d810d
AS
1728}
1729
2658a79a
AS
1730static int init_vqs(struct ports_device *portdev)
1731{
1732 vq_callback_t **io_callbacks;
1733 char **io_names;
1734 struct virtqueue **vqs;
17634ba2 1735 u32 i, j, nr_ports, nr_queues;
2658a79a
AS
1736 int err;
1737
17634ba2
AS
1738 nr_ports = portdev->config.max_nr_ports;
1739 nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2;
2658a79a
AS
1740
1741 vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL);
2658a79a 1742 io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL);
2658a79a 1743 io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL);
2658a79a
AS
1744 portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
1745 GFP_KERNEL);
2658a79a
AS
1746 portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
1747 GFP_KERNEL);
22e132ff 1748 if (!vqs || !io_callbacks || !io_names || !portdev->in_vqs ||
286f9a22 1749 !portdev->out_vqs) {
2658a79a 1750 err = -ENOMEM;
22e132ff 1751 goto free;
2658a79a
AS
1752 }
1753
17634ba2
AS
1754 /*
1755 * For backward compat (newer host but older guest), the host
1756 * spawns a console port first and also inits the vqs for port
1757 * 0 before others.
1758 */
1759 j = 0;
1760 io_callbacks[j] = in_intr;
2770c5ea 1761 io_callbacks[j + 1] = out_intr;
17634ba2
AS
1762 io_names[j] = "input";
1763 io_names[j + 1] = "output";
1764 j += 2;
1765
1766 if (use_multiport(portdev)) {
1767 io_callbacks[j] = control_intr;
1768 io_callbacks[j + 1] = NULL;
1769 io_names[j] = "control-i";
1770 io_names[j + 1] = "control-o";
1771
1772 for (i = 1; i < nr_ports; i++) {
1773 j += 2;
1774 io_callbacks[j] = in_intr;
2770c5ea 1775 io_callbacks[j + 1] = out_intr;
17634ba2
AS
1776 io_names[j] = "input";
1777 io_names[j + 1] = "output";
1778 }
1779 }
2658a79a
AS
1780 /* Find the queues. */
1781 err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
1782 io_callbacks,
1783 (const char **)io_names);
1784 if (err)
22e132ff 1785 goto free;
2658a79a 1786
17634ba2 1787 j = 0;
2658a79a
AS
1788 portdev->in_vqs[0] = vqs[0];
1789 portdev->out_vqs[0] = vqs[1];
17634ba2
AS
1790 j += 2;
1791 if (use_multiport(portdev)) {
1792 portdev->c_ivq = vqs[j];
1793 portdev->c_ovq = vqs[j + 1];
1794
1795 for (i = 1; i < nr_ports; i++) {
1796 j += 2;
1797 portdev->in_vqs[i] = vqs[j];
1798 portdev->out_vqs[i] = vqs[j + 1];
1799 }
1800 }
2658a79a 1801 kfree(io_names);
22e132ff 1802 kfree(io_callbacks);
2658a79a
AS
1803 kfree(vqs);
1804
1805 return 0;
1806
22e132ff 1807free:
2658a79a 1808 kfree(portdev->out_vqs);
2658a79a 1809 kfree(portdev->in_vqs);
22e132ff
JS
1810 kfree(io_names);
1811 kfree(io_callbacks);
2658a79a 1812 kfree(vqs);
22e132ff 1813
2658a79a
AS
1814 return err;
1815}
1816
fb08bd27
AS
1817static const struct file_operations portdev_fops = {
1818 .owner = THIS_MODULE,
1819};
1820
a0e2dbfc
AS
1821static void remove_vqs(struct ports_device *portdev)
1822{
1823 portdev->vdev->config->del_vqs(portdev->vdev);
1824 kfree(portdev->in_vqs);
1825 kfree(portdev->out_vqs);
1826}
1827
1828static void remove_controlq_data(struct ports_device *portdev)
1829{
1830 struct port_buffer *buf;
1831 unsigned int len;
1832
1833 if (!use_multiport(portdev))
1834 return;
1835
1836 while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
1837 free_buf(buf);
1838
1839 while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
1840 free_buf(buf);
1841}
1842
1c85bf35
AS
1843/*
1844 * Once we're further in boot, we get probed like any other virtio
1845 * device.
17634ba2
AS
1846 *
1847 * If the host also supports multiple console ports, we check the
1848 * config space to see how many ports the host has spawned. We
1849 * initialize each port found.
1c85bf35
AS
1850 */
1851static int __devinit virtcons_probe(struct virtio_device *vdev)
1852{
1c85bf35
AS
1853 struct ports_device *portdev;
1854 int err;
17634ba2 1855 bool multiport;
5e38483b
CB
1856 bool early = early_put_chars != NULL;
1857
1858 /* Ensure to read early_put_chars now */
1859 barrier();
1c85bf35
AS
1860
1861 portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
1862 if (!portdev) {
1863 err = -ENOMEM;
1864 goto fail;
1865 }
1866
1867 /* Attach this portdev to this virtio_device, and vice-versa. */
1868 portdev->vdev = vdev;
1869 vdev->priv = portdev;
1870
fb08bd27
AS
1871 spin_lock_irq(&pdrvdata_lock);
1872 portdev->drv_index = pdrvdata.index++;
1873 spin_unlock_irq(&pdrvdata_lock);
1874
1875 portdev->chr_major = register_chrdev(0, "virtio-portsdev",
1876 &portdev_fops);
1877 if (portdev->chr_major < 0) {
1878 dev_err(&vdev->dev,
1879 "Error %d registering chrdev for device %u\n",
1880 portdev->chr_major, portdev->drv_index);
1881 err = portdev->chr_major;
1882 goto free;
1883 }
1884
17634ba2 1885 multiport = false;
17634ba2 1886 portdev->config.max_nr_ports = 1;
51c6d61a
SL
1887 if (virtio_config_val(vdev, VIRTIO_CONSOLE_F_MULTIPORT,
1888 offsetof(struct virtio_console_config,
1889 max_nr_ports),
1890 &portdev->config.max_nr_ports) == 0)
17634ba2 1891 multiport = true;
17634ba2 1892
2658a79a
AS
1893 err = init_vqs(portdev);
1894 if (err < 0) {
1895 dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
fb08bd27 1896 goto free_chrdev;
2658a79a 1897 }
1c85bf35 1898
17634ba2
AS
1899 spin_lock_init(&portdev->ports_lock);
1900 INIT_LIST_HEAD(&portdev->ports);
1901
1902 if (multiport) {
335a64a5
AS
1903 unsigned int nr_added_bufs;
1904
17634ba2
AS
1905 spin_lock_init(&portdev->cvq_lock);
1906 INIT_WORK(&portdev->control_work, &control_work_handler);
1907
335a64a5
AS
1908 nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
1909 if (!nr_added_bufs) {
22a29eac
AS
1910 dev_err(&vdev->dev,
1911 "Error allocating buffers for control queue\n");
1912 err = -ENOMEM;
1913 goto free_vqs;
1914 }
1d05160b
AS
1915 } else {
1916 /*
1917 * For backward compatibility: Create a console port
1918 * if we're running on older host.
1919 */
1920 add_port(portdev, 0);
17634ba2
AS
1921 }
1922
6bdf2afd
AS
1923 spin_lock_irq(&pdrvdata_lock);
1924 list_add_tail(&portdev->list, &pdrvdata.portdevs);
1925 spin_unlock_irq(&pdrvdata_lock);
1926
f909f850
AS
1927 __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
1928 VIRTIO_CONSOLE_DEVICE_READY, 1);
5e38483b
CB
1929
1930 /*
1931 * If there was an early virtio console, assume that there are no
1932 * other consoles. We need to wait until the hvc_alloc matches the
1933 * hvc_instantiate, otherwise tty_open will complain, resulting in
1934 * a "Warning: unable to open an initial console" boot failure.
1935 * Without multiport this is done in add_port above. With multiport
1936 * this might take some host<->guest communication - thus we have to
1937 * wait.
1938 */
1939 if (multiport && early)
1940 wait_for_completion(&early_console_added);
1941
31610434
RR
1942 return 0;
1943
22a29eac 1944free_vqs:
0643e4c6
JL
1945 /* The host might want to notify mgmt sw about device add failure */
1946 __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
1947 VIRTIO_CONSOLE_DEVICE_READY, 0);
a0e2dbfc 1948 remove_vqs(portdev);
fb08bd27
AS
1949free_chrdev:
1950 unregister_chrdev(portdev->chr_major, "virtio-portsdev");
31610434 1951free:
1c85bf35 1952 kfree(portdev);
31610434
RR
1953fail:
1954 return err;
1955}
1956
7177876f
AS
1957static void virtcons_remove(struct virtio_device *vdev)
1958{
1959 struct ports_device *portdev;
1960 struct port *port, *port2;
7177876f
AS
1961
1962 portdev = vdev->priv;
1963
6bdf2afd
AS
1964 spin_lock_irq(&pdrvdata_lock);
1965 list_del(&portdev->list);
1966 spin_unlock_irq(&pdrvdata_lock);
1967
02238959
AS
1968 /* Disable interrupts for vqs */
1969 vdev->config->reset(vdev);
1970 /* Finish up work that's lined up */
7177876f 1971 cancel_work_sync(&portdev->control_work);
7177876f
AS
1972
1973 list_for_each_entry_safe(port, port2, &portdev->ports, list)
b353a6b8 1974 unplug_port(port);
7177876f
AS
1975
1976 unregister_chrdev(portdev->chr_major, "virtio-portsdev");
1977
e062013c
AS
1978 /*
1979 * When yanking out a device, we immediately lose the
1980 * (device-side) queues. So there's no point in keeping the
1981 * guest side around till we drop our final reference. This
1982 * also means that any ports which are in an open state will
1983 * have to just stop using the port, as the vqs are going
1984 * away.
1985 */
a0e2dbfc
AS
1986 remove_controlq_data(portdev);
1987 remove_vqs(portdev);
7177876f
AS
1988 kfree(portdev);
1989}
1990
31610434
RR
1991static struct virtio_device_id id_table[] = {
1992 { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID },
1993 { 0 },
1994};
1995
c2983458
CB
1996static unsigned int features[] = {
1997 VIRTIO_CONSOLE_F_SIZE,
b99fa815 1998 VIRTIO_CONSOLE_F_MULTIPORT,
c2983458
CB
1999};
2000
2b8f41d8
AS
2001#ifdef CONFIG_PM
2002static int virtcons_freeze(struct virtio_device *vdev)
2003{
2004 struct ports_device *portdev;
2005 struct port *port;
2006
2007 portdev = vdev->priv;
2008
2009 vdev->config->reset(vdev);
2010
c743d09d 2011 virtqueue_disable_cb(portdev->c_ivq);
2b8f41d8 2012 cancel_work_sync(&portdev->control_work);
c743d09d
AS
2013 /*
2014 * Once more: if control_work_handler() was running, it would
2015 * enable the cb as the last step.
2016 */
2017 virtqueue_disable_cb(portdev->c_ivq);
2b8f41d8
AS
2018 remove_controlq_data(portdev);
2019
2020 list_for_each_entry(port, &portdev->ports, list) {
c743d09d
AS
2021 virtqueue_disable_cb(port->in_vq);
2022 virtqueue_disable_cb(port->out_vq);
2b8f41d8
AS
2023 /*
2024 * We'll ask the host later if the new invocation has
2025 * the port opened or closed.
2026 */
2027 port->host_connected = false;
2028 remove_port_data(port);
2029 }
2030 remove_vqs(portdev);
2031
2032 return 0;
2033}
2034
2035static int virtcons_restore(struct virtio_device *vdev)
2036{
2037 struct ports_device *portdev;
2038 struct port *port;
2039 int ret;
2040
2041 portdev = vdev->priv;
2042
2043 ret = init_vqs(portdev);
2044 if (ret)
2045 return ret;
2046
2047 if (use_multiport(portdev))
2048 fill_queue(portdev->c_ivq, &portdev->cvq_lock);
2049
2050 list_for_each_entry(port, &portdev->ports, list) {
2051 port->in_vq = portdev->in_vqs[port->id];
2052 port->out_vq = portdev->out_vqs[port->id];
2053
2054 fill_queue(port->in_vq, &port->inbuf_lock);
2055
2056 /* Get port open/close status on the host */
2057 send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
fa8b66cc
AS
2058
2059 /*
2060 * If a port was open at the time of suspending, we
2061 * have to let the host know that it's still open.
2062 */
2063 if (port->guest_connected)
2064 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
2b8f41d8
AS
2065 }
2066 return 0;
2067}
2068#endif
2069
31610434 2070static struct virtio_driver virtio_console = {
c2983458
CB
2071 .feature_table = features,
2072 .feature_table_size = ARRAY_SIZE(features),
31610434
RR
2073 .driver.name = KBUILD_MODNAME,
2074 .driver.owner = THIS_MODULE,
2075 .id_table = id_table,
2076 .probe = virtcons_probe,
7177876f 2077 .remove = virtcons_remove,
7f5d810d 2078 .config_changed = config_intr,
2b8f41d8
AS
2079#ifdef CONFIG_PM
2080 .freeze = virtcons_freeze,
2081 .restore = virtcons_restore,
2082#endif
31610434
RR
2083};
2084
2085static int __init init(void)
2086{
fb08bd27
AS
2087 int err;
2088
2089 pdrvdata.class = class_create(THIS_MODULE, "virtio-ports");
2090 if (IS_ERR(pdrvdata.class)) {
2091 err = PTR_ERR(pdrvdata.class);
2092 pr_err("Error %d creating virtio-ports class\n", err);
2093 return err;
2094 }
d99393ef
AS
2095
2096 pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL);
2097 if (!pdrvdata.debugfs_dir) {
2098 pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
2099 PTR_ERR(pdrvdata.debugfs_dir));
2100 }
38edf58d 2101 INIT_LIST_HEAD(&pdrvdata.consoles);
6bdf2afd 2102 INIT_LIST_HEAD(&pdrvdata.portdevs);
38edf58d 2103
33e1afc3
AK
2104 err = register_virtio_driver(&virtio_console);
2105 if (err < 0) {
2106 pr_err("Error %d registering virtio driver\n", err);
2107 goto free;
2108 }
2109 return 0;
2110free:
2111 if (pdrvdata.debugfs_dir)
2112 debugfs_remove_recursive(pdrvdata.debugfs_dir);
2113 class_destroy(pdrvdata.class);
2114 return err;
31610434 2115}
7177876f
AS
2116
2117static void __exit fini(void)
2118{
2119 unregister_virtio_driver(&virtio_console);
2120
2121 class_destroy(pdrvdata.class);
2122 if (pdrvdata.debugfs_dir)
2123 debugfs_remove_recursive(pdrvdata.debugfs_dir);
2124}
31610434 2125module_init(init);
7177876f 2126module_exit(fini);
31610434
RR
2127
2128MODULE_DEVICE_TABLE(virtio, id_table);
2129MODULE_DESCRIPTION("Virtio console driver");
2130MODULE_LICENSE("GPL");
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