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-rw-r--r--drivers/char/virtio_console.c1578
1 files changed, 1432 insertions, 146 deletions
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index a035ae39a359..213373b5f17f 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1,18 +1,6 @@
1/*D:300 1/*
2 * The Guest console driver 2 * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
3 * 3 * Copyright (C) 2009, 2010 Red Hat, Inc.
4 * Writing console drivers is one of the few remaining Dark Arts in Linux.
5 * Fortunately for us, the path of virtual consoles has been well-trodden by
6 * the PowerPC folks, who wrote "hvc_console.c" to generically support any
7 * virtual console. We use that infrastructure which only requires us to write
8 * the basic put_chars and get_chars functions and call the right register
9 * functions.
10 :*/
11
12/*M:002 The console can be flooded: while the Guest is processing input the
13 * Host can send more. Buffering in the Host could alleviate this, but it is a
14 * difficult problem in general. :*/
15/* Copyright (C) 2006, 2007 Rusty Russell, IBM Corporation
16 * 4 *
17 * This program is free software; you can redistribute it and/or modify 5 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by 6 * it under the terms of the GNU General Public License as published by
@@ -28,142 +16,694 @@
28 * along with this program; if not, write to the Free Software 16 * along with this program; if not, write to the Free Software
29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
30 */ 18 */
19#include <linux/cdev.h>
20#include <linux/debugfs.h>
21#include <linux/device.h>
31#include <linux/err.h> 22#include <linux/err.h>
23#include <linux/fs.h>
32#include <linux/init.h> 24#include <linux/init.h>
25#include <linux/list.h>
26#include <linux/poll.h>
27#include <linux/sched.h>
28#include <linux/spinlock.h>
33#include <linux/virtio.h> 29#include <linux/virtio.h>
34#include <linux/virtio_console.h> 30#include <linux/virtio_console.h>
31#include <linux/wait.h>
32#include <linux/workqueue.h>
35#include "hvc_console.h" 33#include "hvc_console.h"
36 34
37/*D:340 These represent our input and output console queues, and the virtio 35/*
38 * operations for them. */ 36 * This is a global struct for storing common data for all the devices
39static struct virtqueue *in_vq, *out_vq; 37 * this driver handles.
40static struct virtio_device *vdev; 38 *
39 * Mainly, it has a linked list for all the consoles in one place so
40 * that callbacks from hvc for get_chars(), put_chars() work properly
41 * across multiple devices and multiple ports per device.
42 */
43struct ports_driver_data {
44 /* Used for registering chardevs */
45 struct class *class;
46
47 /* Used for exporting per-port information to debugfs */
48 struct dentry *debugfs_dir;
49
50 /* Number of devices this driver is handling */
51 unsigned int index;
52
53 /*
54 * This is used to keep track of the number of hvc consoles
55 * spawned by this driver. This number is given as the first
56 * argument to hvc_alloc(). To correctly map an initial
57 * console spawned via hvc_instantiate to the console being
58 * hooked up via hvc_alloc, we need to pass the same vtermno.
59 *
60 * We also just assume the first console being initialised was
61 * the first one that got used as the initial console.
62 */
63 unsigned int next_vtermno;
64
65 /* All the console devices handled by this driver */
66 struct list_head consoles;
67};
68static struct ports_driver_data pdrvdata;
69
70DEFINE_SPINLOCK(pdrvdata_lock);
71
72/* This struct holds information that's relevant only for console ports */
73struct console {
74 /* We'll place all consoles in a list in the pdrvdata struct */
75 struct list_head list;
76
77 /* The hvc device associated with this console port */
78 struct hvc_struct *hvc;
79
80 /*
81 * This number identifies the number that we used to register
82 * with hvc in hvc_instantiate() and hvc_alloc(); this is the
83 * number passed on by the hvc callbacks to us to
84 * differentiate between the other console ports handled by
85 * this driver
86 */
87 u32 vtermno;
88};
89
90struct port_buffer {
91 char *buf;
92
93 /* size of the buffer in *buf above */
94 size_t size;
95
96 /* used length of the buffer */
97 size_t len;
98 /* offset in the buf from which to consume data */
99 size_t offset;
100};
101
102/*
103 * This is a per-device struct that stores data common to all the
104 * ports for that device (vdev->priv).
105 */
106struct ports_device {
107 /*
108 * Workqueue handlers where we process deferred work after
109 * notification
110 */
111 struct work_struct control_work;
112 struct work_struct config_work;
113
114 struct list_head ports;
115
116 /* To protect the list of ports */
117 spinlock_t ports_lock;
118
119 /* To protect the vq operations for the control channel */
120 spinlock_t cvq_lock;
121
122 /* The current config space is stored here */
123 struct virtio_console_config config;
124
125 /* The virtio device we're associated with */
126 struct virtio_device *vdev;
127
128 /*
129 * A couple of virtqueues for the control channel: one for
130 * guest->host transfers, one for host->guest transfers
131 */
132 struct virtqueue *c_ivq, *c_ovq;
133
134 /* Array of per-port IO virtqueues */
135 struct virtqueue **in_vqs, **out_vqs;
136
137 /* Used for numbering devices for sysfs and debugfs */
138 unsigned int drv_index;
139
140 /* Major number for this device. Ports will be created as minors. */
141 int chr_major;
142};
143
144/* This struct holds the per-port data */
145struct port {
146 /* Next port in the list, head is in the ports_device */
147 struct list_head list;
148
149 /* Pointer to the parent virtio_console device */
150 struct ports_device *portdev;
151
152 /* The current buffer from which data has to be fed to readers */
153 struct port_buffer *inbuf;
154
155 /*
156 * To protect the operations on the in_vq associated with this
157 * port. Has to be a spinlock because it can be called from
158 * interrupt context (get_char()).
159 */
160 spinlock_t inbuf_lock;
161
162 /* The IO vqs for this port */
163 struct virtqueue *in_vq, *out_vq;
164
165 /* File in the debugfs directory that exposes this port's information */
166 struct dentry *debugfs_file;
167
168 /*
169 * The entries in this struct will be valid if this port is
170 * hooked up to an hvc console
171 */
172 struct console cons;
173
174 /* Each port associates with a separate char device */
175 struct cdev cdev;
176 struct device *dev;
177
178 /* A waitqueue for poll() or blocking read operations */
179 wait_queue_head_t waitqueue;
180
181 /* The 'name' of the port that we expose via sysfs properties */
182 char *name;
183
184 /* The 'id' to identify the port with the Host */
185 u32 id;
186
187 /* Is the host device open */
188 bool host_connected;
189
190 /* We should allow only one process to open a port */
191 bool guest_connected;
192};
193
194/* This is the very early arch-specified put chars function. */
195static int (*early_put_chars)(u32, const char *, int);
196
197static struct port *find_port_by_vtermno(u32 vtermno)
198{
199 struct port *port;
200 struct console *cons;
201 unsigned long flags;
202
203 spin_lock_irqsave(&pdrvdata_lock, flags);
204 list_for_each_entry(cons, &pdrvdata.consoles, list) {
205 if (cons->vtermno == vtermno) {
206 port = container_of(cons, struct port, cons);
207 goto out;
208 }
209 }
210 port = NULL;
211out:
212 spin_unlock_irqrestore(&pdrvdata_lock, flags);
213 return port;
214}
215
216static struct port *find_port_by_id(struct ports_device *portdev, u32 id)
217{
218 struct port *port;
219 unsigned long flags;
220
221 spin_lock_irqsave(&portdev->ports_lock, flags);
222 list_for_each_entry(port, &portdev->ports, list)
223 if (port->id == id)
224 goto out;
225 port = NULL;
226out:
227 spin_unlock_irqrestore(&portdev->ports_lock, flags);
228
229 return port;
230}
231
232static struct port *find_port_by_vq(struct ports_device *portdev,
233 struct virtqueue *vq)
234{
235 struct port *port;
236 unsigned long flags;
237
238 spin_lock_irqsave(&portdev->ports_lock, flags);
239 list_for_each_entry(port, &portdev->ports, list)
240 if (port->in_vq == vq || port->out_vq == vq)
241 goto out;
242 port = NULL;
243out:
244 spin_unlock_irqrestore(&portdev->ports_lock, flags);
245 return port;
246}
247
248static bool is_console_port(struct port *port)
249{
250 if (port->cons.hvc)
251 return true;
252 return false;
253}
254
255static inline bool use_multiport(struct ports_device *portdev)
256{
257 /*
258 * This condition can be true when put_chars is called from
259 * early_init
260 */
261 if (!portdev->vdev)
262 return 0;
263 return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
264}
41 265
42/* This is our input buffer, and how much data is left in it. */ 266static void free_buf(struct port_buffer *buf)
43static unsigned int in_len; 267{
44static char *in, *inbuf; 268 kfree(buf->buf);
269 kfree(buf);
270}
271
272static struct port_buffer *alloc_buf(size_t buf_size)
273{
274 struct port_buffer *buf;
45 275
46/* The operations for our console. */ 276 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
47static struct hv_ops virtio_cons; 277 if (!buf)
278 goto fail;
279 buf->buf = kzalloc(buf_size, GFP_KERNEL);
280 if (!buf->buf)
281 goto free_buf;
282 buf->len = 0;
283 buf->offset = 0;
284 buf->size = buf_size;
285 return buf;
286
287free_buf:
288 kfree(buf);
289fail:
290 return NULL;
291}
292
293/* Callers should take appropriate locks */
294static void *get_inbuf(struct port *port)
295{
296 struct port_buffer *buf;
297 struct virtqueue *vq;
298 unsigned int len;
48 299
49/* The hvc device */ 300 vq = port->in_vq;
50static struct hvc_struct *hvc; 301 buf = vq->vq_ops->get_buf(vq, &len);
302 if (buf) {
303 buf->len = len;
304 buf->offset = 0;
305 }
306 return buf;
307}
51 308
52/*D:310 The put_chars() callback is pretty straightforward. 309/*
310 * Create a scatter-gather list representing our input buffer and put
311 * it in the queue.
53 * 312 *
54 * We turn the characters into a scatter-gather list, add it to the output 313 * Callers should take appropriate locks.
55 * queue and then kick the Host. Then we sit here waiting for it to finish: 314 */
56 * inefficient in theory, but in practice implementations will do it 315static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
57 * immediately (lguest's Launcher does). */
58static int put_chars(u32 vtermno, const char *buf, int count)
59{ 316{
60 struct scatterlist sg[1]; 317 struct scatterlist sg[1];
318 int ret;
319
320 sg_init_one(sg, buf->buf, buf->size);
321
322 ret = vq->vq_ops->add_buf(vq, sg, 0, 1, buf);
323 vq->vq_ops->kick(vq);
324 return ret;
325}
326
327/* Discard any unread data this port has. Callers lockers. */
328static void discard_port_data(struct port *port)
329{
330 struct port_buffer *buf;
331 struct virtqueue *vq;
61 unsigned int len; 332 unsigned int len;
333 int ret;
62 334
63 /* This is a convenient routine to initialize a single-elem sg list */ 335 vq = port->in_vq;
64 sg_init_one(sg, buf, count); 336 if (port->inbuf)
337 buf = port->inbuf;
338 else
339 buf = vq->vq_ops->get_buf(vq, &len);
65 340
66 /* add_buf wants a token to identify this buffer: we hand it any 341 ret = 0;
67 * non-NULL pointer, since there's only ever one buffer. */ 342 while (buf) {
68 if (out_vq->vq_ops->add_buf(out_vq, sg, 1, 0, (void *)1) >= 0) { 343 if (add_inbuf(vq, buf) < 0) {
69 /* Tell Host to go! */ 344 ret++;
70 out_vq->vq_ops->kick(out_vq); 345 free_buf(buf);
71 /* Chill out until it's done with the buffer. */ 346 }
72 while (!out_vq->vq_ops->get_buf(out_vq, &len)) 347 buf = vq->vq_ops->get_buf(vq, &len);
73 cpu_relax();
74 } 348 }
349 port->inbuf = NULL;
350 if (ret)
351 dev_warn(port->dev, "Errors adding %d buffers back to vq\n",
352 ret);
353}
75 354
76 /* We're expected to return the amount of data we wrote: all of it. */ 355static bool port_has_data(struct port *port)
77 return count; 356{
357 unsigned long flags;
358 bool ret;
359
360 spin_lock_irqsave(&port->inbuf_lock, flags);
361 if (port->inbuf) {
362 ret = true;
363 goto out;
364 }
365 port->inbuf = get_inbuf(port);
366 if (port->inbuf) {
367 ret = true;
368 goto out;
369 }
370 ret = false;
371out:
372 spin_unlock_irqrestore(&port->inbuf_lock, flags);
373 return ret;
78} 374}
79 375
80/* Create a scatter-gather list representing our input buffer and put it in the 376static ssize_t send_control_msg(struct port *port, unsigned int event,
81 * queue. */ 377 unsigned int value)
82static void add_inbuf(void)
83{ 378{
84 struct scatterlist sg[1]; 379 struct scatterlist sg[1];
85 sg_init_one(sg, inbuf, PAGE_SIZE); 380 struct virtio_console_control cpkt;
381 struct virtqueue *vq;
382 int len;
383
384 if (!use_multiport(port->portdev))
385 return 0;
386
387 cpkt.id = port->id;
388 cpkt.event = event;
389 cpkt.value = value;
390
391 vq = port->portdev->c_ovq;
86 392
87 /* We should always be able to add one buffer to an empty queue. */ 393 sg_init_one(sg, &cpkt, sizeof(cpkt));
88 if (in_vq->vq_ops->add_buf(in_vq, sg, 0, 1, inbuf) < 0) 394 if (vq->vq_ops->add_buf(vq, sg, 1, 0, &cpkt) >= 0) {
89 BUG(); 395 vq->vq_ops->kick(vq);
90 in_vq->vq_ops->kick(in_vq); 396 while (!vq->vq_ops->get_buf(vq, &len))
397 cpu_relax();
398 }
399 return 0;
91} 400}
92 401
93/*D:350 get_chars() is the callback from the hvc_console infrastructure when 402static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count)
94 * an interrupt is received.
95 *
96 * Most of the code deals with the fact that the hvc_console() infrastructure
97 * only asks us for 16 bytes at a time. We keep in_offset and in_used fields
98 * for partially-filled buffers. */
99static int get_chars(u32 vtermno, char *buf, int count)
100{ 403{
101 /* If we don't have an input queue yet, we can't get input. */ 404 struct scatterlist sg[1];
102 BUG_ON(!in_vq); 405 struct virtqueue *out_vq;
406 ssize_t ret;
407 unsigned int len;
408
409 out_vq = port->out_vq;
410
411 sg_init_one(sg, in_buf, in_count);
412 ret = out_vq->vq_ops->add_buf(out_vq, sg, 1, 0, in_buf);
413
414 /* Tell Host to go! */
415 out_vq->vq_ops->kick(out_vq);
416
417 if (ret < 0) {
418 len = 0;
419 goto fail;
420 }
421
422 /*
423 * Wait till the host acknowledges it pushed out the data we
424 * sent. Also ensure we return to userspace the number of
425 * bytes that were successfully consumed by the host.
426 */
427 while (!out_vq->vq_ops->get_buf(out_vq, &len))
428 cpu_relax();
429fail:
430 /* We're expected to return the amount of data we wrote */
431 return len;
432}
433
434/*
435 * Give out the data that's requested from the buffer that we have
436 * queued up.
437 */
438static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count,
439 bool to_user)
440{
441 struct port_buffer *buf;
442 unsigned long flags;
443
444 if (!out_count || !port_has_data(port))
445 return 0;
446
447 buf = port->inbuf;
448 out_count = min(out_count, buf->len - buf->offset);
449
450 if (to_user) {
451 ssize_t ret;
452
453 ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count);
454 if (ret)
455 return -EFAULT;
456 } else {
457 memcpy(out_buf, buf->buf + buf->offset, out_count);
458 }
459
460 buf->offset += out_count;
461
462 if (buf->offset == buf->len) {
463 /*
464 * We're done using all the data in this buffer.
465 * Re-queue so that the Host can send us more data.
466 */
467 spin_lock_irqsave(&port->inbuf_lock, flags);
468 port->inbuf = NULL;
469
470 if (add_inbuf(port->in_vq, buf) < 0)
471 dev_warn(port->dev, "failed add_buf\n");
472
473 spin_unlock_irqrestore(&port->inbuf_lock, flags);
474 }
475 /* Return the number of bytes actually copied */
476 return out_count;
477}
103 478
104 /* No buffer? Try to get one. */ 479/* The condition that must be true for polling to end */
105 if (!in_len) { 480static bool wait_is_over(struct port *port)
106 in = in_vq->vq_ops->get_buf(in_vq, &in_len); 481{
107 if (!in) 482 return port_has_data(port) || !port->host_connected;
483}
484
485static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
486 size_t count, loff_t *offp)
487{
488 struct port *port;
489 ssize_t ret;
490
491 port = filp->private_data;
492
493 if (!port_has_data(port)) {
494 /*
495 * If nothing's connected on the host just return 0 in
496 * case of list_empty; this tells the userspace app
497 * that there's no connection
498 */
499 if (!port->host_connected)
108 return 0; 500 return 0;
501 if (filp->f_flags & O_NONBLOCK)
502 return -EAGAIN;
503
504 ret = wait_event_interruptible(port->waitqueue,
505 wait_is_over(port));
506 if (ret < 0)
507 return ret;
508 }
509 /*
510 * We could've received a disconnection message while we were
511 * waiting for more data.
512 *
513 * This check is not clubbed in the if() statement above as we
514 * might receive some data as well as the host could get
515 * disconnected after we got woken up from our wait. So we
516 * really want to give off whatever data we have and only then
517 * check for host_connected.
518 */
519 if (!port_has_data(port) && !port->host_connected)
520 return 0;
521
522 return fill_readbuf(port, ubuf, count, true);
523}
524
525static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
526 size_t count, loff_t *offp)
527{
528 struct port *port;
529 char *buf;
530 ssize_t ret;
531
532 port = filp->private_data;
533
534 count = min((size_t)(32 * 1024), count);
535
536 buf = kmalloc(count, GFP_KERNEL);
537 if (!buf)
538 return -ENOMEM;
539
540 ret = copy_from_user(buf, ubuf, count);
541 if (ret) {
542 ret = -EFAULT;
543 goto free_buf;
109 } 544 }
110 545
111 /* You want more than we have to give? Well, try wanting less! */ 546 ret = send_buf(port, buf, count);
112 if (in_len < count) 547free_buf:
113 count = in_len; 548 kfree(buf);
549 return ret;
550}
551
552static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
553{
554 struct port *port;
555 unsigned int ret;
556
557 port = filp->private_data;
558 poll_wait(filp, &port->waitqueue, wait);
559
560 ret = 0;
561 if (port->inbuf)
562 ret |= POLLIN | POLLRDNORM;
563 if (port->host_connected)
564 ret |= POLLOUT;
565 if (!port->host_connected)
566 ret |= POLLHUP;
567
568 return ret;
569}
570
571static int port_fops_release(struct inode *inode, struct file *filp)
572{
573 struct port *port;
574
575 port = filp->private_data;
576
577 /* Notify host of port being closed */
578 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
579
580 spin_lock_irq(&port->inbuf_lock);
581 port->guest_connected = false;
582
583 discard_port_data(port);
584
585 spin_unlock_irq(&port->inbuf_lock);
586
587 return 0;
588}
589
590static int port_fops_open(struct inode *inode, struct file *filp)
591{
592 struct cdev *cdev = inode->i_cdev;
593 struct port *port;
594
595 port = container_of(cdev, struct port, cdev);
596 filp->private_data = port;
597
598 /*
599 * Don't allow opening of console port devices -- that's done
600 * via /dev/hvc
601 */
602 if (is_console_port(port))
603 return -ENXIO;
604
605 /* Allow only one process to open a particular port at a time */
606 spin_lock_irq(&port->inbuf_lock);
607 if (port->guest_connected) {
608 spin_unlock_irq(&port->inbuf_lock);
609 return -EMFILE;
610 }
114 611
115 /* Copy across to their buffer and increment offset. */ 612 port->guest_connected = true;
116 memcpy(buf, in, count); 613 spin_unlock_irq(&port->inbuf_lock);
117 in += count;
118 in_len -= count;
119 614
120 /* Finished? Re-register buffer so Host will use it again. */ 615 /* Notify host of port being opened */
121 if (in_len == 0) 616 send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1);
122 add_inbuf();
123 617
124 return count; 618 return 0;
125} 619}
126/*:*/
127 620
128/*D:320 Console drivers are initialized very early so boot messages can go out, 621/*
129 * so we do things slightly differently from the generic virtio initialization 622 * The file operations that we support: programs in the guest can open
130 * of the net and block drivers. 623 * a console device, read from it, write to it, poll for data and
624 * close it. The devices are at
625 * /dev/vport<device number>p<port number>
626 */
627static const struct file_operations port_fops = {
628 .owner = THIS_MODULE,
629 .open = port_fops_open,
630 .read = port_fops_read,
631 .write = port_fops_write,
632 .poll = port_fops_poll,
633 .release = port_fops_release,
634};
635
636/*
637 * The put_chars() callback is pretty straightforward.
131 * 638 *
132 * At this stage, the console is output-only. It's too early to set up a 639 * We turn the characters into a scatter-gather list, add it to the
133 * virtqueue, so we let the drivers do some boutique early-output thing. */ 640 * output queue and then kick the Host. Then we sit here waiting for
134int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int)) 641 * it to finish: inefficient in theory, but in practice
642 * implementations will do it immediately (lguest's Launcher does).
643 */
644static int put_chars(u32 vtermno, const char *buf, int count)
135{ 645{
136 virtio_cons.put_chars = put_chars; 646 struct port *port;
137 return hvc_instantiate(0, 0, &virtio_cons); 647
648 port = find_port_by_vtermno(vtermno);
649 if (!port)
650 return 0;
651
652 if (unlikely(early_put_chars))
653 return early_put_chars(vtermno, buf, count);
654
655 return send_buf(port, (void *)buf, count);
138} 656}
139 657
140/* 658/*
141 * virtio console configuration. This supports: 659 * get_chars() is the callback from the hvc_console infrastructure
142 * - console resize 660 * when an interrupt is received.
661 *
662 * We call out to fill_readbuf that gets us the required data from the
663 * buffers that are queued up.
143 */ 664 */
144static void virtcons_apply_config(struct virtio_device *dev) 665static int get_chars(u32 vtermno, char *buf, int count)
145{ 666{
667 struct port *port;
668
669 port = find_port_by_vtermno(vtermno);
670 if (!port)
671 return 0;
672
673 /* If we don't have an input queue yet, we can't get input. */
674 BUG_ON(!port->in_vq);
675
676 return fill_readbuf(port, buf, count, false);
677}
678
679static void resize_console(struct port *port)
680{
681 struct virtio_device *vdev;
146 struct winsize ws; 682 struct winsize ws;
147 683
148 if (virtio_has_feature(dev, VIRTIO_CONSOLE_F_SIZE)) { 684 vdev = port->portdev->vdev;
149 dev->config->get(dev, 685 if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE)) {
150 offsetof(struct virtio_console_config, cols), 686 vdev->config->get(vdev,
151 &ws.ws_col, sizeof(u16)); 687 offsetof(struct virtio_console_config, cols),
152 dev->config->get(dev, 688 &ws.ws_col, sizeof(u16));
153 offsetof(struct virtio_console_config, rows), 689 vdev->config->get(vdev,
154 &ws.ws_row, sizeof(u16)); 690 offsetof(struct virtio_console_config, rows),
155 hvc_resize(hvc, ws); 691 &ws.ws_row, sizeof(u16));
692 hvc_resize(port->cons.hvc, ws);
156 } 693 }
157} 694}
158 695
159/* 696/* We set the configuration at this point, since we now have a tty */
160 * we support only one console, the hvc struct is a global var
161 * We set the configuration at this point, since we now have a tty
162 */
163static int notifier_add_vio(struct hvc_struct *hp, int data) 697static int notifier_add_vio(struct hvc_struct *hp, int data)
164{ 698{
699 struct port *port;
700
701 port = find_port_by_vtermno(hp->vtermno);
702 if (!port)
703 return -EINVAL;
704
165 hp->irq_requested = 1; 705 hp->irq_requested = 1;
166 virtcons_apply_config(vdev); 706 resize_console(port);
167 707
168 return 0; 708 return 0;
169} 709}
@@ -173,79 +713,797 @@ static void notifier_del_vio(struct hvc_struct *hp, int data)
173 hp->irq_requested = 0; 713 hp->irq_requested = 0;
174} 714}
175 715
176static void hvc_handle_input(struct virtqueue *vq) 716/* The operations for console ports. */
717static const struct hv_ops hv_ops = {
718 .get_chars = get_chars,
719 .put_chars = put_chars,
720 .notifier_add = notifier_add_vio,
721 .notifier_del = notifier_del_vio,
722 .notifier_hangup = notifier_del_vio,
723};
724
725/*
726 * Console drivers are initialized very early so boot messages can go
727 * out, so we do things slightly differently from the generic virtio
728 * initialization of the net and block drivers.
729 *
730 * At this stage, the console is output-only. It's too early to set
731 * up a virtqueue, so we let the drivers do some boutique early-output
732 * thing.
733 */
734int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
177{ 735{
178 if (hvc_poll(hvc)) 736 early_put_chars = put_chars;
737 return hvc_instantiate(0, 0, &hv_ops);
738}
739
740int init_port_console(struct port *port)
741{
742 int ret;
743
744 /*
745 * The Host's telling us this port is a console port. Hook it
746 * up with an hvc console.
747 *
748 * To set up and manage our virtual console, we call
749 * hvc_alloc().
750 *
751 * The first argument of hvc_alloc() is the virtual console
752 * number. The second argument is the parameter for the
753 * notification mechanism (like irq number). We currently
754 * leave this as zero, virtqueues have implicit notifications.
755 *
756 * The third argument is a "struct hv_ops" containing the
757 * put_chars() get_chars(), notifier_add() and notifier_del()
758 * pointers. The final argument is the output buffer size: we
759 * can do any size, so we put PAGE_SIZE here.
760 */
761 port->cons.vtermno = pdrvdata.next_vtermno;
762
763 port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE);
764 if (IS_ERR(port->cons.hvc)) {
765 ret = PTR_ERR(port->cons.hvc);
766 dev_err(port->dev,
767 "error %d allocating hvc for port\n", ret);
768 port->cons.hvc = NULL;
769 return ret;
770 }
771 spin_lock_irq(&pdrvdata_lock);
772 pdrvdata.next_vtermno++;
773 list_add_tail(&port->cons.list, &pdrvdata.consoles);
774 spin_unlock_irq(&pdrvdata_lock);
775 port->guest_connected = true;
776
777 /* Notify host of port being opened */
778 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
779
780 return 0;
781}
782
783static ssize_t show_port_name(struct device *dev,
784 struct device_attribute *attr, char *buffer)
785{
786 struct port *port;
787
788 port = dev_get_drvdata(dev);
789
790 return sprintf(buffer, "%s\n", port->name);
791}
792
793static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL);
794
795static struct attribute *port_sysfs_entries[] = {
796 &dev_attr_name.attr,
797 NULL
798};
799
800static struct attribute_group port_attribute_group = {
801 .name = NULL, /* put in device directory */
802 .attrs = port_sysfs_entries,
803};
804
805static int debugfs_open(struct inode *inode, struct file *filp)
806{
807 filp->private_data = inode->i_private;
808 return 0;
809}
810
811static ssize_t debugfs_read(struct file *filp, char __user *ubuf,
812 size_t count, loff_t *offp)
813{
814 struct port *port;
815 char *buf;
816 ssize_t ret, out_offset, out_count;
817
818 out_count = 1024;
819 buf = kmalloc(out_count, GFP_KERNEL);
820 if (!buf)
821 return -ENOMEM;
822
823 port = filp->private_data;
824 out_offset = 0;
825 out_offset += snprintf(buf + out_offset, out_count,
826 "name: %s\n", port->name ? port->name : "");
827 out_offset += snprintf(buf + out_offset, out_count - out_offset,
828 "guest_connected: %d\n", port->guest_connected);
829 out_offset += snprintf(buf + out_offset, out_count - out_offset,
830 "host_connected: %d\n", port->host_connected);
831 out_offset += snprintf(buf + out_offset, out_count - out_offset,
832 "is_console: %s\n",
833 is_console_port(port) ? "yes" : "no");
834 out_offset += snprintf(buf + out_offset, out_count - out_offset,
835 "console_vtermno: %u\n", port->cons.vtermno);
836
837 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
838 kfree(buf);
839 return ret;
840}
841
842static const struct file_operations port_debugfs_ops = {
843 .owner = THIS_MODULE,
844 .open = debugfs_open,
845 .read = debugfs_read,
846};
847
848/* Remove all port-specific data. */
849static int remove_port(struct port *port)
850{
851 struct port_buffer *buf;
852
853 spin_lock_irq(&port->portdev->ports_lock);
854 list_del(&port->list);
855 spin_unlock_irq(&port->portdev->ports_lock);
856
857 if (is_console_port(port)) {
858 spin_lock_irq(&pdrvdata_lock);
859 list_del(&port->cons.list);
860 spin_unlock_irq(&pdrvdata_lock);
861 hvc_remove(port->cons.hvc);
862 }
863 if (port->guest_connected)
864 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
865
866 sysfs_remove_group(&port->dev->kobj, &port_attribute_group);
867 device_destroy(pdrvdata.class, port->dev->devt);
868 cdev_del(&port->cdev);
869
870 /* Remove unused data this port might have received. */
871 discard_port_data(port);
872
873 /* Remove buffers we queued up for the Host to send us data in. */
874 while ((buf = port->in_vq->vq_ops->detach_unused_buf(port->in_vq)))
875 free_buf(buf);
876
877 kfree(port->name);
878
879 debugfs_remove(port->debugfs_file);
880
881 kfree(port);
882 return 0;
883}
884
885/* Any private messages that the Host and Guest want to share */
886static void handle_control_message(struct ports_device *portdev,
887 struct port_buffer *buf)
888{
889 struct virtio_console_control *cpkt;
890 struct port *port;
891 size_t name_size;
892 int err;
893
894 cpkt = (struct virtio_console_control *)(buf->buf + buf->offset);
895
896 port = find_port_by_id(portdev, cpkt->id);
897 if (!port) {
898 /* No valid header at start of buffer. Drop it. */
899 dev_dbg(&portdev->vdev->dev,
900 "Invalid index %u in control packet\n", cpkt->id);
901 return;
902 }
903
904 switch (cpkt->event) {
905 case VIRTIO_CONSOLE_CONSOLE_PORT:
906 if (!cpkt->value)
907 break;
908 if (is_console_port(port))
909 break;
910
911 init_port_console(port);
912 /*
913 * Could remove the port here in case init fails - but
914 * have to notify the host first.
915 */
916 break;
917 case VIRTIO_CONSOLE_RESIZE:
918 if (!is_console_port(port))
919 break;
920 port->cons.hvc->irq_requested = 1;
921 resize_console(port);
922 break;
923 case VIRTIO_CONSOLE_PORT_OPEN:
924 port->host_connected = cpkt->value;
925 wake_up_interruptible(&port->waitqueue);
926 break;
927 case VIRTIO_CONSOLE_PORT_NAME:
928 /*
929 * Skip the size of the header and the cpkt to get the size
930 * of the name that was sent
931 */
932 name_size = buf->len - buf->offset - sizeof(*cpkt) + 1;
933
934 port->name = kmalloc(name_size, GFP_KERNEL);
935 if (!port->name) {
936 dev_err(port->dev,
937 "Not enough space to store port name\n");
938 break;
939 }
940 strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt),
941 name_size - 1);
942 port->name[name_size - 1] = 0;
943
944 /*
945 * Since we only have one sysfs attribute, 'name',
946 * create it only if we have a name for the port.
947 */
948 err = sysfs_create_group(&port->dev->kobj,
949 &port_attribute_group);
950 if (err)
951 dev_err(port->dev,
952 "Error %d creating sysfs device attributes\n",
953 err);
954
955 break;
956 case VIRTIO_CONSOLE_PORT_REMOVE:
957 /*
958 * Hot unplug the port. We don't decrement nr_ports
959 * since we don't want to deal with extra complexities
960 * of using the lowest-available port id: We can just
961 * pick up the nr_ports number as the id and not have
962 * userspace send it to us. This helps us in two
963 * ways:
964 *
965 * - We don't need to have a 'port_id' field in the
966 * config space when a port is hot-added. This is a
967 * good thing as we might queue up multiple hotplug
968 * requests issued in our workqueue.
969 *
970 * - Another way to deal with this would have been to
971 * use a bitmap of the active ports and select the
972 * lowest non-active port from that map. That
973 * bloats the already tight config space and we
974 * would end up artificially limiting the
975 * max. number of ports to sizeof(bitmap). Right
976 * now we can support 2^32 ports (as the port id is
977 * stored in a u32 type).
978 *
979 */
980 remove_port(port);
981 break;
982 }
983}
984
985static void control_work_handler(struct work_struct *work)
986{
987 struct ports_device *portdev;
988 struct virtqueue *vq;
989 struct port_buffer *buf;
990 unsigned int len;
991
992 portdev = container_of(work, struct ports_device, control_work);
993 vq = portdev->c_ivq;
994
995 spin_lock(&portdev->cvq_lock);
996 while ((buf = vq->vq_ops->get_buf(vq, &len))) {
997 spin_unlock(&portdev->cvq_lock);
998
999 buf->len = len;
1000 buf->offset = 0;
1001
1002 handle_control_message(portdev, buf);
1003
1004 spin_lock(&portdev->cvq_lock);
1005 if (add_inbuf(portdev->c_ivq, buf) < 0) {
1006 dev_warn(&portdev->vdev->dev,
1007 "Error adding buffer to queue\n");
1008 free_buf(buf);
1009 }
1010 }
1011 spin_unlock(&portdev->cvq_lock);
1012}
1013
1014static void in_intr(struct virtqueue *vq)
1015{
1016 struct port *port;
1017 unsigned long flags;
1018
1019 port = find_port_by_vq(vq->vdev->priv, vq);
1020 if (!port)
1021 return;
1022
1023 spin_lock_irqsave(&port->inbuf_lock, flags);
1024 if (!port->inbuf)
1025 port->inbuf = get_inbuf(port);
1026
1027 /*
1028 * Don't queue up data when port is closed. This condition
1029 * can be reached when a console port is not yet connected (no
1030 * tty is spawned) and the host sends out data to console
1031 * ports. For generic serial ports, the host won't
1032 * (shouldn't) send data till the guest is connected.
1033 */
1034 if (!port->guest_connected)
1035 discard_port_data(port);
1036
1037 spin_unlock_irqrestore(&port->inbuf_lock, flags);
1038
1039 wake_up_interruptible(&port->waitqueue);
1040
1041 if (is_console_port(port) && hvc_poll(port->cons.hvc))
179 hvc_kick(); 1042 hvc_kick();
180} 1043}
181 1044
182/*D:370 Once we're further in boot, we get probed like any other virtio device. 1045static void control_intr(struct virtqueue *vq)
183 * At this stage we set up the output virtqueue. 1046{
184 * 1047 struct ports_device *portdev;
185 * To set up and manage our virtual console, we call hvc_alloc(). Since we 1048
186 * never remove the console device we never need this pointer again. 1049 portdev = vq->vdev->priv;
1050 schedule_work(&portdev->control_work);
1051}
1052
1053static void config_intr(struct virtio_device *vdev)
1054{
1055 struct ports_device *portdev;
1056
1057 portdev = vdev->priv;
1058 if (use_multiport(portdev)) {
1059 /* Handle port hot-add */
1060 schedule_work(&portdev->config_work);
1061 }
1062 /*
1063 * We'll use this way of resizing only for legacy support.
1064 * For newer userspace (VIRTIO_CONSOLE_F_MULTPORT+), use
1065 * control messages to indicate console size changes so that
1066 * it can be done per-port
1067 */
1068 resize_console(find_port_by_id(portdev, 0));
1069}
1070
1071static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
1072{
1073 struct port_buffer *buf;
1074 unsigned int ret;
1075 int err;
1076
1077 ret = 0;
1078 do {
1079 buf = alloc_buf(PAGE_SIZE);
1080 if (!buf)
1081 break;
1082
1083 spin_lock_irq(lock);
1084 err = add_inbuf(vq, buf);
1085 if (err < 0) {
1086 spin_unlock_irq(lock);
1087 free_buf(buf);
1088 break;
1089 }
1090 ret++;
1091 spin_unlock_irq(lock);
1092 } while (err > 0);
1093
1094 return ret;
1095}
1096
1097static int add_port(struct ports_device *portdev, u32 id)
1098{
1099 char debugfs_name[16];
1100 struct port *port;
1101 struct port_buffer *buf;
1102 dev_t devt;
1103 int err;
1104
1105 port = kmalloc(sizeof(*port), GFP_KERNEL);
1106 if (!port) {
1107 err = -ENOMEM;
1108 goto fail;
1109 }
1110
1111 port->portdev = portdev;
1112 port->id = id;
1113
1114 port->name = NULL;
1115 port->inbuf = NULL;
1116 port->cons.hvc = NULL;
1117
1118 port->host_connected = port->guest_connected = false;
1119
1120 port->in_vq = portdev->in_vqs[port->id];
1121 port->out_vq = portdev->out_vqs[port->id];
1122
1123 cdev_init(&port->cdev, &port_fops);
1124
1125 devt = MKDEV(portdev->chr_major, id);
1126 err = cdev_add(&port->cdev, devt, 1);
1127 if (err < 0) {
1128 dev_err(&port->portdev->vdev->dev,
1129 "Error %d adding cdev for port %u\n", err, id);
1130 goto free_port;
1131 }
1132 port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
1133 devt, port, "vport%up%u",
1134 port->portdev->drv_index, id);
1135 if (IS_ERR(port->dev)) {
1136 err = PTR_ERR(port->dev);
1137 dev_err(&port->portdev->vdev->dev,
1138 "Error %d creating device for port %u\n",
1139 err, id);
1140 goto free_cdev;
1141 }
1142
1143 spin_lock_init(&port->inbuf_lock);
1144 init_waitqueue_head(&port->waitqueue);
1145
1146 /* Fill the in_vq with buffers so the host can send us data. */
1147 err = fill_queue(port->in_vq, &port->inbuf_lock);
1148 if (!err) {
1149 dev_err(port->dev, "Error allocating inbufs\n");
1150 err = -ENOMEM;
1151 goto free_device;
1152 }
1153
1154 /*
1155 * If we're not using multiport support, this has to be a console port
1156 */
1157 if (!use_multiport(port->portdev)) {
1158 err = init_port_console(port);
1159 if (err)
1160 goto free_inbufs;
1161 }
1162
1163 spin_lock_irq(&portdev->ports_lock);
1164 list_add_tail(&port->list, &port->portdev->ports);
1165 spin_unlock_irq(&portdev->ports_lock);
1166
1167 /*
1168 * Tell the Host we're set so that it can send us various
1169 * configuration parameters for this port (eg, port name,
1170 * caching, whether this is a console port, etc.)
1171 */
1172 send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
1173
1174 if (pdrvdata.debugfs_dir) {
1175 /*
1176 * Finally, create the debugfs file that we can use to
1177 * inspect a port's state at any time
1178 */
1179 sprintf(debugfs_name, "vport%up%u",
1180 port->portdev->drv_index, id);
1181 port->debugfs_file = debugfs_create_file(debugfs_name, 0444,
1182 pdrvdata.debugfs_dir,
1183 port,
1184 &port_debugfs_ops);
1185 }
1186 return 0;
1187
1188free_inbufs:
1189 while ((buf = port->in_vq->vq_ops->detach_unused_buf(port->in_vq)))
1190 free_buf(buf);
1191free_device:
1192 device_destroy(pdrvdata.class, port->dev->devt);
1193free_cdev:
1194 cdev_del(&port->cdev);
1195free_port:
1196 kfree(port);
1197fail:
1198 return err;
1199}
1200
1201/*
1202 * The workhandler for config-space updates.
187 * 1203 *
188 * Finally we put our input buffer in the input queue, ready to receive. */ 1204 * This is called when ports are hot-added.
189static int __devinit virtcons_probe(struct virtio_device *dev) 1205 */
1206static void config_work_handler(struct work_struct *work)
1207{
1208 struct virtio_console_config virtconconf;
1209 struct ports_device *portdev;
1210 struct virtio_device *vdev;
1211 int err;
1212
1213 portdev = container_of(work, struct ports_device, config_work);
1214
1215 vdev = portdev->vdev;
1216 vdev->config->get(vdev,
1217 offsetof(struct virtio_console_config, nr_ports),
1218 &virtconconf.nr_ports,
1219 sizeof(virtconconf.nr_ports));
1220
1221 if (portdev->config.nr_ports == virtconconf.nr_ports) {
1222 /*
1223 * Port 0 got hot-added. Since we already did all the
1224 * other initialisation for it, just tell the Host
1225 * that the port is ready if we find the port. In
1226 * case the port was hot-removed earlier, we call
1227 * add_port to add the port.
1228 */
1229 struct port *port;
1230
1231 port = find_port_by_id(portdev, 0);
1232 if (!port)
1233 add_port(portdev, 0);
1234 else
1235 send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
1236 return;
1237 }
1238 if (virtconconf.nr_ports > portdev->config.max_nr_ports) {
1239 dev_warn(&vdev->dev,
1240 "More ports specified (%u) than allowed (%u)",
1241 portdev->config.nr_ports + 1,
1242 portdev->config.max_nr_ports);
1243 return;
1244 }
1245 if (virtconconf.nr_ports < portdev->config.nr_ports)
1246 return;
1247
1248 /* Hot-add ports */
1249 while (virtconconf.nr_ports - portdev->config.nr_ports) {
1250 err = add_port(portdev, portdev->config.nr_ports);
1251 if (err)
1252 break;
1253 portdev->config.nr_ports++;
1254 }
1255}
1256
1257static int init_vqs(struct ports_device *portdev)
190{ 1258{
191 vq_callback_t *callbacks[] = { hvc_handle_input, NULL}; 1259 vq_callback_t **io_callbacks;
192 const char *names[] = { "input", "output" }; 1260 char **io_names;
193 struct virtqueue *vqs[2]; 1261 struct virtqueue **vqs;
1262 u32 i, j, nr_ports, nr_queues;
194 int err; 1263 int err;
195 1264
196 vdev = dev; 1265 nr_ports = portdev->config.max_nr_ports;
1266 nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2;
197 1267
198 /* This is the scratch page we use to receive console input */ 1268 vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL);
199 inbuf = kmalloc(PAGE_SIZE, GFP_KERNEL); 1269 if (!vqs) {
200 if (!inbuf) {
201 err = -ENOMEM; 1270 err = -ENOMEM;
202 goto fail; 1271 goto fail;
203 } 1272 }
1273 io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL);
1274 if (!io_callbacks) {
1275 err = -ENOMEM;
1276 goto free_vqs;
1277 }
1278 io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL);
1279 if (!io_names) {
1280 err = -ENOMEM;
1281 goto free_callbacks;
1282 }
1283 portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
1284 GFP_KERNEL);
1285 if (!portdev->in_vqs) {
1286 err = -ENOMEM;
1287 goto free_names;
1288 }
1289 portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
1290 GFP_KERNEL);
1291 if (!portdev->out_vqs) {
1292 err = -ENOMEM;
1293 goto free_invqs;
1294 }
1295
1296 /*
1297 * For backward compat (newer host but older guest), the host
1298 * spawns a console port first and also inits the vqs for port
1299 * 0 before others.
1300 */
1301 j = 0;
1302 io_callbacks[j] = in_intr;
1303 io_callbacks[j + 1] = NULL;
1304 io_names[j] = "input";
1305 io_names[j + 1] = "output";
1306 j += 2;
204 1307
1308 if (use_multiport(portdev)) {
1309 io_callbacks[j] = control_intr;
1310 io_callbacks[j + 1] = NULL;
1311 io_names[j] = "control-i";
1312 io_names[j + 1] = "control-o";
1313
1314 for (i = 1; i < nr_ports; i++) {
1315 j += 2;
1316 io_callbacks[j] = in_intr;
1317 io_callbacks[j + 1] = NULL;
1318 io_names[j] = "input";
1319 io_names[j + 1] = "output";
1320 }
1321 }
205 /* Find the queues. */ 1322 /* Find the queues. */
206 /* FIXME: This is why we want to wean off hvc: we do nothing 1323 err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
207 * when input comes in. */ 1324 io_callbacks,
208 err = vdev->config->find_vqs(vdev, 2, vqs, callbacks, names); 1325 (const char **)io_names);
209 if (err) 1326 if (err)
1327 goto free_outvqs;
1328
1329 j = 0;
1330 portdev->in_vqs[0] = vqs[0];
1331 portdev->out_vqs[0] = vqs[1];
1332 j += 2;
1333 if (use_multiport(portdev)) {
1334 portdev->c_ivq = vqs[j];
1335 portdev->c_ovq = vqs[j + 1];
1336
1337 for (i = 1; i < nr_ports; i++) {
1338 j += 2;
1339 portdev->in_vqs[i] = vqs[j];
1340 portdev->out_vqs[i] = vqs[j + 1];
1341 }
1342 }
1343 kfree(io_callbacks);
1344 kfree(io_names);
1345 kfree(vqs);
1346
1347 return 0;
1348
1349free_names:
1350 kfree(io_names);
1351free_callbacks:
1352 kfree(io_callbacks);
1353free_outvqs:
1354 kfree(portdev->out_vqs);
1355free_invqs:
1356 kfree(portdev->in_vqs);
1357free_vqs:
1358 kfree(vqs);
1359fail:
1360 return err;
1361}
1362
1363static const struct file_operations portdev_fops = {
1364 .owner = THIS_MODULE,
1365};
1366
1367/*
1368 * Once we're further in boot, we get probed like any other virtio
1369 * device.
1370 *
1371 * If the host also supports multiple console ports, we check the
1372 * config space to see how many ports the host has spawned. We
1373 * initialize each port found.
1374 */
1375static int __devinit virtcons_probe(struct virtio_device *vdev)
1376{
1377 struct ports_device *portdev;
1378 u32 i;
1379 int err;
1380 bool multiport;
1381
1382 portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
1383 if (!portdev) {
1384 err = -ENOMEM;
1385 goto fail;
1386 }
1387
1388 /* Attach this portdev to this virtio_device, and vice-versa. */
1389 portdev->vdev = vdev;
1390 vdev->priv = portdev;
1391
1392 spin_lock_irq(&pdrvdata_lock);
1393 portdev->drv_index = pdrvdata.index++;
1394 spin_unlock_irq(&pdrvdata_lock);
1395
1396 portdev->chr_major = register_chrdev(0, "virtio-portsdev",
1397 &portdev_fops);
1398 if (portdev->chr_major < 0) {
1399 dev_err(&vdev->dev,
1400 "Error %d registering chrdev for device %u\n",
1401 portdev->chr_major, portdev->drv_index);
1402 err = portdev->chr_major;
210 goto free; 1403 goto free;
1404 }
211 1405
212 in_vq = vqs[0]; 1406 multiport = false;
213 out_vq = vqs[1]; 1407 portdev->config.nr_ports = 1;
1408 portdev->config.max_nr_ports = 1;
1409 if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
1410 multiport = true;
1411 vdev->features[0] |= 1 << VIRTIO_CONSOLE_F_MULTIPORT;
214 1412
215 /* Start using the new console output. */ 1413 vdev->config->get(vdev, offsetof(struct virtio_console_config,
216 virtio_cons.get_chars = get_chars; 1414 nr_ports),
217 virtio_cons.put_chars = put_chars; 1415 &portdev->config.nr_ports,
218 virtio_cons.notifier_add = notifier_add_vio; 1416 sizeof(portdev->config.nr_ports));
219 virtio_cons.notifier_del = notifier_del_vio; 1417 vdev->config->get(vdev, offsetof(struct virtio_console_config,
220 virtio_cons.notifier_hangup = notifier_del_vio; 1418 max_nr_ports),
221 1419 &portdev->config.max_nr_ports,
222 /* The first argument of hvc_alloc() is the virtual console number, so 1420 sizeof(portdev->config.max_nr_ports));
223 * we use zero. The second argument is the parameter for the 1421 if (portdev->config.nr_ports > portdev->config.max_nr_ports) {
224 * notification mechanism (like irq number). We currently leave this 1422 dev_warn(&vdev->dev,
225 * as zero, virtqueues have implicit notifications. 1423 "More ports (%u) specified than allowed (%u). Will init %u ports.",
226 * 1424 portdev->config.nr_ports,
227 * The third argument is a "struct hv_ops" containing the put_chars() 1425 portdev->config.max_nr_ports,
228 * get_chars(), notifier_add() and notifier_del() pointers. 1426 portdev->config.max_nr_ports);
229 * The final argument is the output buffer size: we can do any size, 1427
230 * so we put PAGE_SIZE here. */ 1428 portdev->config.nr_ports = portdev->config.max_nr_ports;
231 hvc = hvc_alloc(0, 0, &virtio_cons, PAGE_SIZE); 1429 }
232 if (IS_ERR(hvc)) { 1430 }
233 err = PTR_ERR(hvc); 1431
234 goto free_vqs; 1432 /* Let the Host know we support multiple ports.*/
1433 vdev->config->finalize_features(vdev);
1434
1435 err = init_vqs(portdev);
1436 if (err < 0) {
1437 dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
1438 goto free_chrdev;
1439 }
1440
1441 spin_lock_init(&portdev->ports_lock);
1442 INIT_LIST_HEAD(&portdev->ports);
1443
1444 if (multiport) {
1445 spin_lock_init(&portdev->cvq_lock);
1446 INIT_WORK(&portdev->control_work, &control_work_handler);
1447 INIT_WORK(&portdev->config_work, &config_work_handler);
1448
1449 err = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
1450 if (!err) {
1451 dev_err(&vdev->dev,
1452 "Error allocating buffers for control queue\n");
1453 err = -ENOMEM;
1454 goto free_vqs;
1455 }
235 } 1456 }
236 1457
237 /* Register the input buffer the first time. */ 1458 for (i = 0; i < portdev->config.nr_ports; i++)
238 add_inbuf(); 1459 add_port(portdev, i);
1460
1461 /* Start using the new console output. */
1462 early_put_chars = NULL;
239 return 0; 1463 return 0;
240 1464
241free_vqs: 1465free_vqs:
242 vdev->config->del_vqs(vdev); 1466 vdev->config->del_vqs(vdev);
1467 kfree(portdev->in_vqs);
1468 kfree(portdev->out_vqs);
1469free_chrdev:
1470 unregister_chrdev(portdev->chr_major, "virtio-portsdev");
243free: 1471free:
244 kfree(inbuf); 1472 kfree(portdev);
245fail: 1473fail:
246 return err; 1474 return err;
247} 1475}
248 1476
1477static void virtcons_remove(struct virtio_device *vdev)
1478{
1479 struct ports_device *portdev;
1480 struct port *port, *port2;
1481 struct port_buffer *buf;
1482 unsigned int len;
1483
1484 portdev = vdev->priv;
1485
1486 cancel_work_sync(&portdev->control_work);
1487 cancel_work_sync(&portdev->config_work);
1488
1489 list_for_each_entry_safe(port, port2, &portdev->ports, list)
1490 remove_port(port);
1491
1492 unregister_chrdev(portdev->chr_major, "virtio-portsdev");
1493
1494 while ((buf = portdev->c_ivq->vq_ops->get_buf(portdev->c_ivq, &len)))
1495 free_buf(buf);
1496
1497 while ((buf = portdev->c_ivq->vq_ops->detach_unused_buf(portdev->c_ivq)))
1498 free_buf(buf);
1499
1500 vdev->config->del_vqs(vdev);
1501 kfree(portdev->in_vqs);
1502 kfree(portdev->out_vqs);
1503
1504 kfree(portdev);
1505}
1506
249static struct virtio_device_id id_table[] = { 1507static struct virtio_device_id id_table[] = {
250 { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID }, 1508 { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID },
251 { 0 }, 1509 { 0 },
@@ -253,6 +1511,7 @@ static struct virtio_device_id id_table[] = {
253 1511
254static unsigned int features[] = { 1512static unsigned int features[] = {
255 VIRTIO_CONSOLE_F_SIZE, 1513 VIRTIO_CONSOLE_F_SIZE,
1514 VIRTIO_CONSOLE_F_MULTIPORT,
256}; 1515};
257 1516
258static struct virtio_driver virtio_console = { 1517static struct virtio_driver virtio_console = {
@@ -262,14 +1521,41 @@ static struct virtio_driver virtio_console = {
262 .driver.owner = THIS_MODULE, 1521 .driver.owner = THIS_MODULE,
263 .id_table = id_table, 1522 .id_table = id_table,
264 .probe = virtcons_probe, 1523 .probe = virtcons_probe,
265 .config_changed = virtcons_apply_config, 1524 .remove = virtcons_remove,
1525 .config_changed = config_intr,
266}; 1526};
267 1527
268static int __init init(void) 1528static int __init init(void)
269{ 1529{
1530 int err;
1531
1532 pdrvdata.class = class_create(THIS_MODULE, "virtio-ports");
1533 if (IS_ERR(pdrvdata.class)) {
1534 err = PTR_ERR(pdrvdata.class);
1535 pr_err("Error %d creating virtio-ports class\n", err);
1536 return err;
1537 }
1538
1539 pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL);
1540 if (!pdrvdata.debugfs_dir) {
1541 pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
1542 PTR_ERR(pdrvdata.debugfs_dir));
1543 }
1544 INIT_LIST_HEAD(&pdrvdata.consoles);
1545
270 return register_virtio_driver(&virtio_console); 1546 return register_virtio_driver(&virtio_console);
271} 1547}
1548
1549static void __exit fini(void)
1550{
1551 unregister_virtio_driver(&virtio_console);
1552
1553 class_destroy(pdrvdata.class);
1554 if (pdrvdata.debugfs_dir)
1555 debugfs_remove_recursive(pdrvdata.debugfs_dir);
1556}
272module_init(init); 1557module_init(init);
1558module_exit(fini);
273 1559
274MODULE_DEVICE_TABLE(virtio, id_table); 1560MODULE_DEVICE_TABLE(virtio, id_table);
275MODULE_DESCRIPTION("Virtio console driver"); 1561MODULE_DESCRIPTION("Virtio console driver");
generated by cgit v1.2.2 (git 2.25.0) at 2025-11-03 13:40:39 -0500