blob: 6c1b676643a9ef43fe3984bb8495996960cf4337 [file] [log] [blame]
Rusty Russella23ea922010-01-18 19:14:55 +05301/*
2 * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
Amit Shah17634ba2009-12-21 21:03:25 +05303 * Copyright (C) 2009, 2010 Red Hat, Inc.
Rusty Russell31610432007-10-22 11:03:39 +10004 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
Amit Shahfb08bd22009-12-21 21:36:04 +053019#include <linux/cdev.h>
Amit Shahd99393e2009-12-21 22:36:21 +053020#include <linux/debugfs.h>
Amit Shahfb08bd22009-12-21 21:36:04 +053021#include <linux/device.h>
Rusty Russell31610432007-10-22 11:03:39 +100022#include <linux/err.h>
Amit Shah2030fa42009-12-21 21:49:30 +053023#include <linux/fs.h>
Rusty Russell31610432007-10-22 11:03:39 +100024#include <linux/init.h>
Amit Shah38edf582010-01-18 19:15:05 +053025#include <linux/list.h>
Amit Shah2030fa42009-12-21 21:49:30 +053026#include <linux/poll.h>
27#include <linux/sched.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090028#include <linux/slab.h>
Amit Shah38edf582010-01-18 19:15:05 +053029#include <linux/spinlock.h>
Rusty Russell31610432007-10-22 11:03:39 +100030#include <linux/virtio.h>
31#include <linux/virtio_console.h>
Amit Shah2030fa42009-12-21 21:49:30 +053032#include <linux/wait.h>
Amit Shah17634ba2009-12-21 21:03:25 +053033#include <linux/workqueue.h>
Rusty Russell31610432007-10-22 11:03:39 +100034#include "hvc_console.h"
35
Amit Shah38edf582010-01-18 19:15:05 +053036/*
37 * This is a global struct for storing common data for all the devices
38 * this driver handles.
39 *
40 * Mainly, it has a linked list for all the consoles in one place so
41 * that callbacks from hvc for get_chars(), put_chars() work properly
42 * across multiple devices and multiple ports per device.
43 */
44struct ports_driver_data {
Amit Shahfb08bd22009-12-21 21:36:04 +053045 /* Used for registering chardevs */
46 struct class *class;
47
Amit Shahd99393e2009-12-21 22:36:21 +053048 /* Used for exporting per-port information to debugfs */
49 struct dentry *debugfs_dir;
50
Amit Shah6bdf2af2010-09-02 18:11:49 +053051 /* List of all the devices we're handling */
52 struct list_head portdevs;
53
Amit Shahfb08bd22009-12-21 21:36:04 +053054 /* Number of devices this driver is handling */
55 unsigned int index;
56
Rusty Russelld8a02bd2010-01-18 19:15:06 +053057 /*
58 * This is used to keep track of the number of hvc consoles
59 * spawned by this driver. This number is given as the first
60 * argument to hvc_alloc(). To correctly map an initial
61 * console spawned via hvc_instantiate to the console being
62 * hooked up via hvc_alloc, we need to pass the same vtermno.
63 *
64 * We also just assume the first console being initialised was
65 * the first one that got used as the initial console.
66 */
67 unsigned int next_vtermno;
68
Amit Shah38edf582010-01-18 19:15:05 +053069 /* All the console devices handled by this driver */
70 struct list_head consoles;
71};
72static struct ports_driver_data pdrvdata;
73
74DEFINE_SPINLOCK(pdrvdata_lock);
75
Amit Shah4f23c572010-01-18 19:15:09 +053076/* This struct holds information that's relevant only for console ports */
77struct console {
78 /* We'll place all consoles in a list in the pdrvdata struct */
79 struct list_head list;
80
81 /* The hvc device associated with this console port */
82 struct hvc_struct *hvc;
83
Amit Shah97788292010-05-06 02:05:08 +053084 /* The size of the console */
85 struct winsize ws;
86
Amit Shah4f23c572010-01-18 19:15:09 +053087 /*
88 * This number identifies the number that we used to register
89 * with hvc in hvc_instantiate() and hvc_alloc(); this is the
90 * number passed on by the hvc callbacks to us to
91 * differentiate between the other console ports handled by
92 * this driver
93 */
94 u32 vtermno;
95};
96
Amit Shahfdb9a052010-01-18 19:15:01 +053097struct port_buffer {
98 char *buf;
99
100 /* size of the buffer in *buf above */
101 size_t size;
102
103 /* used length of the buffer */
104 size_t len;
105 /* offset in the buf from which to consume data */
106 size_t offset;
107};
108
Amit Shah17634ba2009-12-21 21:03:25 +0530109/*
110 * This is a per-device struct that stores data common to all the
111 * ports for that device (vdev->priv).
112 */
113struct ports_device {
Amit Shah6bdf2af2010-09-02 18:11:49 +0530114 /* Next portdev in the list, head is in the pdrvdata struct */
115 struct list_head list;
116
Amit Shah17634ba2009-12-21 21:03:25 +0530117 /*
118 * Workqueue handlers where we process deferred work after
119 * notification
120 */
121 struct work_struct control_work;
122
123 struct list_head ports;
124
125 /* To protect the list of ports */
126 spinlock_t ports_lock;
127
128 /* To protect the vq operations for the control channel */
129 spinlock_t cvq_lock;
130
131 /* The current config space is stored here */
Amit Shahb99fa812010-05-19 22:15:46 -0600132 struct virtio_console_config config;
Amit Shah17634ba2009-12-21 21:03:25 +0530133
134 /* The virtio device we're associated with */
135 struct virtio_device *vdev;
136
137 /*
138 * A couple of virtqueues for the control channel: one for
139 * guest->host transfers, one for host->guest transfers
140 */
141 struct virtqueue *c_ivq, *c_ovq;
142
143 /* Array of per-port IO virtqueues */
144 struct virtqueue **in_vqs, **out_vqs;
Amit Shahfb08bd22009-12-21 21:36:04 +0530145
146 /* Used for numbering devices for sysfs and debugfs */
147 unsigned int drv_index;
148
149 /* Major number for this device. Ports will be created as minors. */
150 int chr_major;
Amit Shah17634ba2009-12-21 21:03:25 +0530151};
152
Amit Shah1c85bf32010-01-18 19:15:07 +0530153/* This struct holds the per-port data */
Rusty Russell21206ed2010-01-18 19:15:00 +0530154struct port {
Amit Shah17634ba2009-12-21 21:03:25 +0530155 /* Next port in the list, head is in the ports_device */
156 struct list_head list;
157
Amit Shah1c85bf32010-01-18 19:15:07 +0530158 /* Pointer to the parent virtio_console device */
159 struct ports_device *portdev;
Amit Shahfdb9a052010-01-18 19:15:01 +0530160
161 /* The current buffer from which data has to be fed to readers */
162 struct port_buffer *inbuf;
Rusty Russell31610432007-10-22 11:03:39 +1000163
Amit Shah203baab2010-01-18 19:15:12 +0530164 /*
165 * To protect the operations on the in_vq associated with this
166 * port. Has to be a spinlock because it can be called from
167 * interrupt context (get_char()).
168 */
169 spinlock_t inbuf_lock;
170
Amit Shahcdfadfc2010-05-19 22:15:50 -0600171 /* Protect the operations on the out_vq. */
172 spinlock_t outvq_lock;
173
Amit Shah1c85bf32010-01-18 19:15:07 +0530174 /* The IO vqs for this port */
175 struct virtqueue *in_vq, *out_vq;
176
Amit Shahd99393e2009-12-21 22:36:21 +0530177 /* File in the debugfs directory that exposes this port's information */
178 struct dentry *debugfs_file;
179
Amit Shah4f23c572010-01-18 19:15:09 +0530180 /*
181 * The entries in this struct will be valid if this port is
182 * hooked up to an hvc console
183 */
184 struct console cons;
Amit Shah17634ba2009-12-21 21:03:25 +0530185
Amit Shahfb08bd22009-12-21 21:36:04 +0530186 /* Each port associates with a separate char device */
Amit Shahd22a6982010-09-02 18:20:59 +0530187 struct cdev *cdev;
Amit Shahfb08bd22009-12-21 21:36:04 +0530188 struct device *dev;
189
Amit Shahb353a6b2010-09-02 18:38:29 +0530190 /* Reference-counting to handle port hot-unplugs and file operations */
191 struct kref kref;
192
Amit Shah2030fa42009-12-21 21:49:30 +0530193 /* A waitqueue for poll() or blocking read operations */
194 wait_queue_head_t waitqueue;
195
Amit Shah431edb82009-12-21 21:57:40 +0530196 /* The 'name' of the port that we expose via sysfs properties */
197 char *name;
198
Amit Shah3eae0ad2010-09-02 18:47:52 +0530199 /* We can notify apps of host connect / disconnect events via SIGIO */
200 struct fasync_struct *async_queue;
201
Amit Shah17634ba2009-12-21 21:03:25 +0530202 /* The 'id' to identify the port with the Host */
203 u32 id;
Amit Shah2030fa42009-12-21 21:49:30 +0530204
Amit Shahcdfadfc2010-05-19 22:15:50 -0600205 bool outvq_full;
206
Amit Shah2030fa42009-12-21 21:49:30 +0530207 /* Is the host device open */
208 bool host_connected;
Amit Shah3c7969c2009-11-26 11:25:38 +0530209
210 /* We should allow only one process to open a port */
211 bool guest_connected;
Rusty Russell21206ed2010-01-18 19:15:00 +0530212};
Rusty Russell31610432007-10-22 11:03:39 +1000213
Rusty Russell971f3392010-01-18 19:14:56 +0530214/* This is the very early arch-specified put chars function. */
215static int (*early_put_chars)(u32, const char *, int);
216
Amit Shah38edf582010-01-18 19:15:05 +0530217static struct port *find_port_by_vtermno(u32 vtermno)
218{
219 struct port *port;
Amit Shah4f23c572010-01-18 19:15:09 +0530220 struct console *cons;
Amit Shah38edf582010-01-18 19:15:05 +0530221 unsigned long flags;
222
223 spin_lock_irqsave(&pdrvdata_lock, flags);
Amit Shah4f23c572010-01-18 19:15:09 +0530224 list_for_each_entry(cons, &pdrvdata.consoles, list) {
225 if (cons->vtermno == vtermno) {
226 port = container_of(cons, struct port, cons);
Amit Shah38edf582010-01-18 19:15:05 +0530227 goto out;
Amit Shah4f23c572010-01-18 19:15:09 +0530228 }
Amit Shah38edf582010-01-18 19:15:05 +0530229 }
230 port = NULL;
231out:
232 spin_unlock_irqrestore(&pdrvdata_lock, flags);
233 return port;
234}
235
Amit Shah04950cd2010-09-02 18:20:58 +0530236static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev,
237 dev_t dev)
238{
239 struct port *port;
240 unsigned long flags;
241
242 spin_lock_irqsave(&portdev->ports_lock, flags);
243 list_for_each_entry(port, &portdev->ports, list)
Amit Shahd22a6982010-09-02 18:20:59 +0530244 if (port->cdev->dev == dev)
Amit Shah04950cd2010-09-02 18:20:58 +0530245 goto out;
246 port = NULL;
247out:
248 spin_unlock_irqrestore(&portdev->ports_lock, flags);
249
250 return port;
251}
252
253static struct port *find_port_by_devt(dev_t dev)
254{
255 struct ports_device *portdev;
256 struct port *port;
257 unsigned long flags;
258
259 spin_lock_irqsave(&pdrvdata_lock, flags);
260 list_for_each_entry(portdev, &pdrvdata.portdevs, list) {
261 port = find_port_by_devt_in_portdev(portdev, dev);
262 if (port)
263 goto out;
264 }
265 port = NULL;
266out:
267 spin_unlock_irqrestore(&pdrvdata_lock, flags);
268 return port;
269}
270
Amit Shah17634ba2009-12-21 21:03:25 +0530271static struct port *find_port_by_id(struct ports_device *portdev, u32 id)
272{
273 struct port *port;
274 unsigned long flags;
275
276 spin_lock_irqsave(&portdev->ports_lock, flags);
277 list_for_each_entry(port, &portdev->ports, list)
278 if (port->id == id)
279 goto out;
280 port = NULL;
281out:
282 spin_unlock_irqrestore(&portdev->ports_lock, flags);
283
284 return port;
285}
286
Amit Shah203baab2010-01-18 19:15:12 +0530287static struct port *find_port_by_vq(struct ports_device *portdev,
288 struct virtqueue *vq)
289{
290 struct port *port;
Amit Shah203baab2010-01-18 19:15:12 +0530291 unsigned long flags;
292
Amit Shah17634ba2009-12-21 21:03:25 +0530293 spin_lock_irqsave(&portdev->ports_lock, flags);
294 list_for_each_entry(port, &portdev->ports, list)
Amit Shah203baab2010-01-18 19:15:12 +0530295 if (port->in_vq == vq || port->out_vq == vq)
296 goto out;
Amit Shah203baab2010-01-18 19:15:12 +0530297 port = NULL;
298out:
Amit Shah17634ba2009-12-21 21:03:25 +0530299 spin_unlock_irqrestore(&portdev->ports_lock, flags);
Amit Shah203baab2010-01-18 19:15:12 +0530300 return port;
301}
302
Amit Shah17634ba2009-12-21 21:03:25 +0530303static bool is_console_port(struct port *port)
304{
305 if (port->cons.hvc)
306 return true;
307 return false;
308}
309
310static inline bool use_multiport(struct ports_device *portdev)
311{
312 /*
313 * This condition can be true when put_chars is called from
314 * early_init
315 */
316 if (!portdev->vdev)
317 return 0;
318 return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
319}
320
Amit Shahfdb9a052010-01-18 19:15:01 +0530321static void free_buf(struct port_buffer *buf)
322{
323 kfree(buf->buf);
324 kfree(buf);
325}
326
327static struct port_buffer *alloc_buf(size_t buf_size)
328{
329 struct port_buffer *buf;
330
331 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
332 if (!buf)
333 goto fail;
334 buf->buf = kzalloc(buf_size, GFP_KERNEL);
335 if (!buf->buf)
336 goto free_buf;
337 buf->len = 0;
338 buf->offset = 0;
339 buf->size = buf_size;
340 return buf;
341
342free_buf:
343 kfree(buf);
344fail:
345 return NULL;
346}
347
Amit Shaha3cde442010-01-18 19:15:03 +0530348/* Callers should take appropriate locks */
349static void *get_inbuf(struct port *port)
350{
351 struct port_buffer *buf;
352 struct virtqueue *vq;
353 unsigned int len;
354
355 vq = port->in_vq;
Michael S. Tsirkin505b0452010-04-12 16:18:32 +0300356 buf = virtqueue_get_buf(vq, &len);
Amit Shaha3cde442010-01-18 19:15:03 +0530357 if (buf) {
358 buf->len = len;
359 buf->offset = 0;
360 }
361 return buf;
362}
363
Rusty Russella23ea922010-01-18 19:14:55 +0530364/*
Amit Shahe27b5192010-01-18 19:15:02 +0530365 * Create a scatter-gather list representing our input buffer and put
366 * it in the queue.
367 *
368 * Callers should take appropriate locks.
369 */
Amit Shah203baab2010-01-18 19:15:12 +0530370static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
Amit Shahe27b5192010-01-18 19:15:02 +0530371{
372 struct scatterlist sg[1];
Amit Shah203baab2010-01-18 19:15:12 +0530373 int ret;
Amit Shah1c85bf32010-01-18 19:15:07 +0530374
Amit Shahe27b5192010-01-18 19:15:02 +0530375 sg_init_one(sg, buf->buf, buf->size);
376
Michael S. Tsirkin505b0452010-04-12 16:18:32 +0300377 ret = virtqueue_add_buf(vq, sg, 0, 1, buf);
378 virtqueue_kick(vq);
Amit Shah203baab2010-01-18 19:15:12 +0530379 return ret;
380}
381
Amit Shah88f251a2009-12-21 22:15:30 +0530382/* Discard any unread data this port has. Callers lockers. */
383static void discard_port_data(struct port *port)
384{
385 struct port_buffer *buf;
386 struct virtqueue *vq;
387 unsigned int len;
Amit Shahd6933562010-02-12 10:32:18 +0530388 int ret;
Amit Shah88f251a2009-12-21 22:15:30 +0530389
390 vq = port->in_vq;
391 if (port->inbuf)
392 buf = port->inbuf;
393 else
Michael S. Tsirkin505b0452010-04-12 16:18:32 +0300394 buf = virtqueue_get_buf(vq, &len);
Amit Shah88f251a2009-12-21 22:15:30 +0530395
Amit Shahd6933562010-02-12 10:32:18 +0530396 ret = 0;
397 while (buf) {
398 if (add_inbuf(vq, buf) < 0) {
399 ret++;
400 free_buf(buf);
401 }
Michael S. Tsirkin505b0452010-04-12 16:18:32 +0300402 buf = virtqueue_get_buf(vq, &len);
Amit Shah88f251a2009-12-21 22:15:30 +0530403 }
Amit Shah88f251a2009-12-21 22:15:30 +0530404 port->inbuf = NULL;
Amit Shahd6933562010-02-12 10:32:18 +0530405 if (ret)
406 dev_warn(port->dev, "Errors adding %d buffers back to vq\n",
407 ret);
Amit Shah88f251a2009-12-21 22:15:30 +0530408}
409
Amit Shah203baab2010-01-18 19:15:12 +0530410static bool port_has_data(struct port *port)
411{
412 unsigned long flags;
413 bool ret;
414
Amit Shah203baab2010-01-18 19:15:12 +0530415 spin_lock_irqsave(&port->inbuf_lock, flags);
Amit Shahd6933562010-02-12 10:32:18 +0530416 if (port->inbuf) {
Amit Shah203baab2010-01-18 19:15:12 +0530417 ret = true;
Amit Shahd6933562010-02-12 10:32:18 +0530418 goto out;
419 }
420 port->inbuf = get_inbuf(port);
421 if (port->inbuf) {
422 ret = true;
423 goto out;
424 }
425 ret = false;
426out:
Amit Shah203baab2010-01-18 19:15:12 +0530427 spin_unlock_irqrestore(&port->inbuf_lock, flags);
Amit Shah203baab2010-01-18 19:15:12 +0530428 return ret;
429}
430
Amit Shah3425e702010-05-19 22:15:46 -0600431static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
432 unsigned int event, unsigned int value)
Amit Shah17634ba2009-12-21 21:03:25 +0530433{
434 struct scatterlist sg[1];
435 struct virtio_console_control cpkt;
436 struct virtqueue *vq;
Amit Shah604b2ad2010-02-24 10:36:51 +0530437 unsigned int len;
Amit Shah17634ba2009-12-21 21:03:25 +0530438
Amit Shah3425e702010-05-19 22:15:46 -0600439 if (!use_multiport(portdev))
Amit Shah17634ba2009-12-21 21:03:25 +0530440 return 0;
441
Amit Shah3425e702010-05-19 22:15:46 -0600442 cpkt.id = port_id;
Amit Shah17634ba2009-12-21 21:03:25 +0530443 cpkt.event = event;
444 cpkt.value = value;
445
Amit Shah3425e702010-05-19 22:15:46 -0600446 vq = portdev->c_ovq;
Amit Shah17634ba2009-12-21 21:03:25 +0530447
448 sg_init_one(sg, &cpkt, sizeof(cpkt));
Michael S. Tsirkin505b0452010-04-12 16:18:32 +0300449 if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt) >= 0) {
450 virtqueue_kick(vq);
451 while (!virtqueue_get_buf(vq, &len))
Amit Shah17634ba2009-12-21 21:03:25 +0530452 cpu_relax();
453 }
454 return 0;
455}
456
Amit Shah3425e702010-05-19 22:15:46 -0600457static ssize_t send_control_msg(struct port *port, unsigned int event,
458 unsigned int value)
459{
Amit Shah84ec06c2010-09-02 18:11:42 +0530460 /* Did the port get unplugged before userspace closed it? */
461 if (port->portdev)
462 return __send_control_msg(port->portdev, port->id, event, value);
463 return 0;
Amit Shah3425e702010-05-19 22:15:46 -0600464}
465
Amit Shahcdfadfc2010-05-19 22:15:50 -0600466/* Callers must take the port->outvq_lock */
467static void reclaim_consumed_buffers(struct port *port)
468{
469 void *buf;
470 unsigned int len;
471
472 while ((buf = virtqueue_get_buf(port->out_vq, &len))) {
473 kfree(buf);
474 port->outvq_full = false;
475 }
476}
477
478static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
479 bool nonblock)
Amit Shahf997f00b2009-12-21 17:28:51 +0530480{
481 struct scatterlist sg[1];
482 struct virtqueue *out_vq;
483 ssize_t ret;
Amit Shahcdfadfc2010-05-19 22:15:50 -0600484 unsigned long flags;
Amit Shahf997f00b2009-12-21 17:28:51 +0530485 unsigned int len;
486
487 out_vq = port->out_vq;
488
Amit Shahcdfadfc2010-05-19 22:15:50 -0600489 spin_lock_irqsave(&port->outvq_lock, flags);
490
491 reclaim_consumed_buffers(port);
492
Amit Shahf997f00b2009-12-21 17:28:51 +0530493 sg_init_one(sg, in_buf, in_count);
Michael S. Tsirkin505b0452010-04-12 16:18:32 +0300494 ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf);
Amit Shahf997f00b2009-12-21 17:28:51 +0530495
496 /* Tell Host to go! */
Michael S. Tsirkin505b0452010-04-12 16:18:32 +0300497 virtqueue_kick(out_vq);
Amit Shahf997f00b2009-12-21 17:28:51 +0530498
499 if (ret < 0) {
Rusty Russell9ff4cfa2010-04-08 09:46:16 -0600500 in_count = 0;
Amit Shahcdfadfc2010-05-19 22:15:50 -0600501 goto done;
Amit Shahf997f00b2009-12-21 17:28:51 +0530502 }
503
Amit Shahcdfadfc2010-05-19 22:15:50 -0600504 if (ret == 0)
505 port->outvq_full = true;
506
507 if (nonblock)
508 goto done;
509
510 /*
511 * Wait till the host acknowledges it pushed out the data we
Amit Shah531295e2010-10-20 13:45:43 +1030512 * sent. This is done for data from the hvc_console; the tty
513 * operations are performed with spinlocks held so we can't
514 * sleep here. An alternative would be to copy the data to a
515 * buffer and relax the spinning requirement. The downside is
516 * we need to kmalloc a GFP_ATOMIC buffer each time the
517 * console driver writes something out.
Amit Shahcdfadfc2010-05-19 22:15:50 -0600518 */
Michael S. Tsirkin505b0452010-04-12 16:18:32 +0300519 while (!virtqueue_get_buf(out_vq, &len))
Amit Shahf997f00b2009-12-21 17:28:51 +0530520 cpu_relax();
Amit Shahcdfadfc2010-05-19 22:15:50 -0600521done:
522 spin_unlock_irqrestore(&port->outvq_lock, flags);
523 /*
524 * We're expected to return the amount of data we wrote -- all
525 * of it
526 */
Rusty Russell9ff4cfa2010-04-08 09:46:16 -0600527 return in_count;
Amit Shahf997f00b2009-12-21 17:28:51 +0530528}
529
Amit Shah203baab2010-01-18 19:15:12 +0530530/*
531 * Give out the data that's requested from the buffer that we have
532 * queued up.
533 */
Amit Shahb766cee2009-12-21 21:26:45 +0530534static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count,
535 bool to_user)
Amit Shah203baab2010-01-18 19:15:12 +0530536{
537 struct port_buffer *buf;
538 unsigned long flags;
539
540 if (!out_count || !port_has_data(port))
541 return 0;
542
543 buf = port->inbuf;
Amit Shahb766cee2009-12-21 21:26:45 +0530544 out_count = min(out_count, buf->len - buf->offset);
Amit Shah203baab2010-01-18 19:15:12 +0530545
Amit Shahb766cee2009-12-21 21:26:45 +0530546 if (to_user) {
547 ssize_t ret;
Amit Shah203baab2010-01-18 19:15:12 +0530548
Amit Shahb766cee2009-12-21 21:26:45 +0530549 ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count);
550 if (ret)
551 return -EFAULT;
552 } else {
553 memcpy(out_buf, buf->buf + buf->offset, out_count);
554 }
555
Amit Shah203baab2010-01-18 19:15:12 +0530556 buf->offset += out_count;
557
558 if (buf->offset == buf->len) {
559 /*
560 * We're done using all the data in this buffer.
561 * Re-queue so that the Host can send us more data.
562 */
563 spin_lock_irqsave(&port->inbuf_lock, flags);
564 port->inbuf = NULL;
565
566 if (add_inbuf(port->in_vq, buf) < 0)
Amit Shahfb08bd22009-12-21 21:36:04 +0530567 dev_warn(port->dev, "failed add_buf\n");
Amit Shah203baab2010-01-18 19:15:12 +0530568
569 spin_unlock_irqrestore(&port->inbuf_lock, flags);
570 }
Amit Shahb766cee2009-12-21 21:26:45 +0530571 /* Return the number of bytes actually copied */
Amit Shah203baab2010-01-18 19:15:12 +0530572 return out_count;
Amit Shahe27b5192010-01-18 19:15:02 +0530573}
574
Amit Shah2030fa42009-12-21 21:49:30 +0530575/* The condition that must be true for polling to end */
Amit Shah60caacd2010-05-19 22:15:49 -0600576static bool will_read_block(struct port *port)
Amit Shah2030fa42009-12-21 21:49:30 +0530577{
Amit Shah3709ea72010-09-02 18:11:43 +0530578 if (!port->guest_connected) {
579 /* Port got hot-unplugged. Let's exit. */
580 return false;
581 }
Amit Shah60caacd2010-05-19 22:15:49 -0600582 return !port_has_data(port) && port->host_connected;
Amit Shah2030fa42009-12-21 21:49:30 +0530583}
584
Amit Shahcdfadfc2010-05-19 22:15:50 -0600585static bool will_write_block(struct port *port)
586{
587 bool ret;
588
Amit Shah60e5e0b2010-05-27 13:24:40 +0530589 if (!port->guest_connected) {
590 /* Port got hot-unplugged. Let's exit. */
591 return false;
592 }
Amit Shahcdfadfc2010-05-19 22:15:50 -0600593 if (!port->host_connected)
594 return true;
595
596 spin_lock_irq(&port->outvq_lock);
597 /*
598 * Check if the Host has consumed any buffers since we last
599 * sent data (this is only applicable for nonblocking ports).
600 */
601 reclaim_consumed_buffers(port);
602 ret = port->outvq_full;
603 spin_unlock_irq(&port->outvq_lock);
604
605 return ret;
606}
607
Amit Shah2030fa42009-12-21 21:49:30 +0530608static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
609 size_t count, loff_t *offp)
610{
611 struct port *port;
612 ssize_t ret;
613
614 port = filp->private_data;
615
616 if (!port_has_data(port)) {
617 /*
618 * If nothing's connected on the host just return 0 in
619 * case of list_empty; this tells the userspace app
620 * that there's no connection
621 */
622 if (!port->host_connected)
623 return 0;
624 if (filp->f_flags & O_NONBLOCK)
625 return -EAGAIN;
626
627 ret = wait_event_interruptible(port->waitqueue,
Amit Shah60caacd2010-05-19 22:15:49 -0600628 !will_read_block(port));
Amit Shah2030fa42009-12-21 21:49:30 +0530629 if (ret < 0)
630 return ret;
631 }
Amit Shahb3dddb92010-09-02 18:11:45 +0530632 /* Port got hot-unplugged. */
633 if (!port->guest_connected)
634 return -ENODEV;
Amit Shah2030fa42009-12-21 21:49:30 +0530635 /*
636 * We could've received a disconnection message while we were
637 * waiting for more data.
638 *
639 * This check is not clubbed in the if() statement above as we
640 * might receive some data as well as the host could get
641 * disconnected after we got woken up from our wait. So we
642 * really want to give off whatever data we have and only then
643 * check for host_connected.
644 */
645 if (!port_has_data(port) && !port->host_connected)
646 return 0;
647
648 return fill_readbuf(port, ubuf, count, true);
649}
650
651static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
652 size_t count, loff_t *offp)
653{
654 struct port *port;
655 char *buf;
656 ssize_t ret;
Amit Shahcdfadfc2010-05-19 22:15:50 -0600657 bool nonblock;
Amit Shah2030fa42009-12-21 21:49:30 +0530658
Amit Shah65745422010-09-14 13:26:16 +0530659 /* Userspace could be out to fool us */
660 if (!count)
661 return 0;
662
Amit Shah2030fa42009-12-21 21:49:30 +0530663 port = filp->private_data;
664
Amit Shahcdfadfc2010-05-19 22:15:50 -0600665 nonblock = filp->f_flags & O_NONBLOCK;
666
667 if (will_write_block(port)) {
668 if (nonblock)
669 return -EAGAIN;
670
671 ret = wait_event_interruptible(port->waitqueue,
672 !will_write_block(port));
673 if (ret < 0)
674 return ret;
675 }
Amit Shahf4028112010-09-02 18:11:46 +0530676 /* Port got hot-unplugged. */
677 if (!port->guest_connected)
678 return -ENODEV;
Amit Shahcdfadfc2010-05-19 22:15:50 -0600679
Amit Shah2030fa42009-12-21 21:49:30 +0530680 count = min((size_t)(32 * 1024), count);
681
682 buf = kmalloc(count, GFP_KERNEL);
683 if (!buf)
684 return -ENOMEM;
685
686 ret = copy_from_user(buf, ubuf, count);
687 if (ret) {
688 ret = -EFAULT;
689 goto free_buf;
690 }
691
Amit Shah531295e2010-10-20 13:45:43 +1030692 /*
693 * We now ask send_buf() to not spin for generic ports -- we
694 * can re-use the same code path that non-blocking file
695 * descriptors take for blocking file descriptors since the
696 * wait is already done and we're certain the write will go
697 * through to the host.
698 */
699 nonblock = true;
Amit Shahcdfadfc2010-05-19 22:15:50 -0600700 ret = send_buf(port, buf, count, nonblock);
701
702 if (nonblock && ret > 0)
703 goto out;
704
Amit Shah2030fa42009-12-21 21:49:30 +0530705free_buf:
706 kfree(buf);
Amit Shahcdfadfc2010-05-19 22:15:50 -0600707out:
Amit Shah2030fa42009-12-21 21:49:30 +0530708 return ret;
709}
710
711static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
712{
713 struct port *port;
714 unsigned int ret;
715
716 port = filp->private_data;
717 poll_wait(filp, &port->waitqueue, wait);
718
Amit Shah8529a502010-09-02 18:11:44 +0530719 if (!port->guest_connected) {
720 /* Port got unplugged */
721 return POLLHUP;
722 }
Amit Shah2030fa42009-12-21 21:49:30 +0530723 ret = 0;
Hans de Goede6df7aad2010-09-16 14:43:08 +0530724 if (!will_read_block(port))
Amit Shah2030fa42009-12-21 21:49:30 +0530725 ret |= POLLIN | POLLRDNORM;
Amit Shahcdfadfc2010-05-19 22:15:50 -0600726 if (!will_write_block(port))
Amit Shah2030fa42009-12-21 21:49:30 +0530727 ret |= POLLOUT;
728 if (!port->host_connected)
729 ret |= POLLHUP;
730
731 return ret;
732}
733
Amit Shahb353a6b2010-09-02 18:38:29 +0530734static void remove_port(struct kref *kref);
735
Amit Shah2030fa42009-12-21 21:49:30 +0530736static int port_fops_release(struct inode *inode, struct file *filp)
737{
738 struct port *port;
739
740 port = filp->private_data;
741
742 /* Notify host of port being closed */
743 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
744
Amit Shah88f251a2009-12-21 22:15:30 +0530745 spin_lock_irq(&port->inbuf_lock);
Amit Shah3c7969c2009-11-26 11:25:38 +0530746 port->guest_connected = false;
747
Amit Shah88f251a2009-12-21 22:15:30 +0530748 discard_port_data(port);
749
750 spin_unlock_irq(&port->inbuf_lock);
751
Amit Shahcdfadfc2010-05-19 22:15:50 -0600752 spin_lock_irq(&port->outvq_lock);
753 reclaim_consumed_buffers(port);
754 spin_unlock_irq(&port->outvq_lock);
755
Amit Shahb353a6b2010-09-02 18:38:29 +0530756 /*
757 * Locks aren't necessary here as a port can't be opened after
758 * unplug, and if a port isn't unplugged, a kref would already
759 * exist for the port. Plus, taking ports_lock here would
760 * create a dependency on other locks taken by functions
761 * inside remove_port if we're the last holder of the port,
762 * creating many problems.
763 */
764 kref_put(&port->kref, remove_port);
765
Amit Shah2030fa42009-12-21 21:49:30 +0530766 return 0;
767}
768
769static int port_fops_open(struct inode *inode, struct file *filp)
770{
771 struct cdev *cdev = inode->i_cdev;
772 struct port *port;
Amit Shah8ad37e82010-09-02 18:11:48 +0530773 int ret;
Amit Shah2030fa42009-12-21 21:49:30 +0530774
Amit Shah04950cd2010-09-02 18:20:58 +0530775 port = find_port_by_devt(cdev->dev);
Amit Shah2030fa42009-12-21 21:49:30 +0530776 filp->private_data = port;
777
Amit Shahb353a6b2010-09-02 18:38:29 +0530778 /* Prevent against a port getting hot-unplugged at the same time */
779 spin_lock_irq(&port->portdev->ports_lock);
780 kref_get(&port->kref);
781 spin_unlock_irq(&port->portdev->ports_lock);
782
Amit Shah2030fa42009-12-21 21:49:30 +0530783 /*
784 * Don't allow opening of console port devices -- that's done
785 * via /dev/hvc
786 */
Amit Shah8ad37e82010-09-02 18:11:48 +0530787 if (is_console_port(port)) {
788 ret = -ENXIO;
789 goto out;
790 }
Amit Shah2030fa42009-12-21 21:49:30 +0530791
Amit Shah3c7969c2009-11-26 11:25:38 +0530792 /* Allow only one process to open a particular port at a time */
793 spin_lock_irq(&port->inbuf_lock);
794 if (port->guest_connected) {
795 spin_unlock_irq(&port->inbuf_lock);
Amit Shah8ad37e82010-09-02 18:11:48 +0530796 ret = -EMFILE;
797 goto out;
Amit Shah3c7969c2009-11-26 11:25:38 +0530798 }
799
800 port->guest_connected = true;
801 spin_unlock_irq(&port->inbuf_lock);
802
Amit Shahcdfadfc2010-05-19 22:15:50 -0600803 spin_lock_irq(&port->outvq_lock);
804 /*
805 * There might be a chance that we missed reclaiming a few
806 * buffers in the window of the port getting previously closed
807 * and opening now.
808 */
809 reclaim_consumed_buffers(port);
810 spin_unlock_irq(&port->outvq_lock);
811
Amit Shah299fb612010-09-16 14:43:09 +0530812 nonseekable_open(inode, filp);
813
Amit Shah2030fa42009-12-21 21:49:30 +0530814 /* Notify host of port being opened */
815 send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1);
816
817 return 0;
Amit Shah8ad37e82010-09-02 18:11:48 +0530818out:
Amit Shahb353a6b2010-09-02 18:38:29 +0530819 kref_put(&port->kref, remove_port);
Amit Shah8ad37e82010-09-02 18:11:48 +0530820 return ret;
Amit Shah2030fa42009-12-21 21:49:30 +0530821}
822
Amit Shah3eae0ad2010-09-02 18:47:52 +0530823static int port_fops_fasync(int fd, struct file *filp, int mode)
824{
825 struct port *port;
826
827 port = filp->private_data;
828 return fasync_helper(fd, filp, mode, &port->async_queue);
829}
830
Amit Shah2030fa42009-12-21 21:49:30 +0530831/*
832 * The file operations that we support: programs in the guest can open
833 * a console device, read from it, write to it, poll for data and
834 * close it. The devices are at
835 * /dev/vport<device number>p<port number>
836 */
837static const struct file_operations port_fops = {
838 .owner = THIS_MODULE,
839 .open = port_fops_open,
840 .read = port_fops_read,
841 .write = port_fops_write,
842 .poll = port_fops_poll,
843 .release = port_fops_release,
Amit Shah3eae0ad2010-09-02 18:47:52 +0530844 .fasync = port_fops_fasync,
Amit Shah299fb612010-09-16 14:43:09 +0530845 .llseek = no_llseek,
Amit Shah2030fa42009-12-21 21:49:30 +0530846};
847
Amit Shahe27b5192010-01-18 19:15:02 +0530848/*
Rusty Russella23ea922010-01-18 19:14:55 +0530849 * The put_chars() callback is pretty straightforward.
Rusty Russell31610432007-10-22 11:03:39 +1000850 *
Rusty Russella23ea922010-01-18 19:14:55 +0530851 * We turn the characters into a scatter-gather list, add it to the
852 * output queue and then kick the Host. Then we sit here waiting for
853 * it to finish: inefficient in theory, but in practice
854 * implementations will do it immediately (lguest's Launcher does).
855 */
Rusty Russell31610432007-10-22 11:03:39 +1000856static int put_chars(u32 vtermno, const char *buf, int count)
857{
Rusty Russell21206ed2010-01-18 19:15:00 +0530858 struct port *port;
Amit Shah38edf582010-01-18 19:15:05 +0530859
François Diakhaté162a6892010-03-23 18:23:15 +0530860 if (unlikely(early_put_chars))
861 return early_put_chars(vtermno, buf, count);
862
Amit Shah38edf582010-01-18 19:15:05 +0530863 port = find_port_by_vtermno(vtermno);
864 if (!port)
Amit Shah6dc69f972010-05-19 22:15:47 -0600865 return -EPIPE;
Rusty Russell31610432007-10-22 11:03:39 +1000866
Amit Shahcdfadfc2010-05-19 22:15:50 -0600867 return send_buf(port, (void *)buf, count, false);
Rusty Russell31610432007-10-22 11:03:39 +1000868}
869
Rusty Russella23ea922010-01-18 19:14:55 +0530870/*
Rusty Russella23ea922010-01-18 19:14:55 +0530871 * get_chars() is the callback from the hvc_console infrastructure
872 * when an interrupt is received.
Rusty Russell31610432007-10-22 11:03:39 +1000873 *
Amit Shah203baab2010-01-18 19:15:12 +0530874 * We call out to fill_readbuf that gets us the required data from the
875 * buffers that are queued up.
Rusty Russella23ea922010-01-18 19:14:55 +0530876 */
Rusty Russell31610432007-10-22 11:03:39 +1000877static int get_chars(u32 vtermno, char *buf, int count)
878{
Rusty Russell21206ed2010-01-18 19:15:00 +0530879 struct port *port;
Rusty Russell31610432007-10-22 11:03:39 +1000880
Amit Shah6dc69f972010-05-19 22:15:47 -0600881 /* If we've not set up the port yet, we have no input to give. */
882 if (unlikely(early_put_chars))
883 return 0;
884
Amit Shah38edf582010-01-18 19:15:05 +0530885 port = find_port_by_vtermno(vtermno);
886 if (!port)
Amit Shah6dc69f972010-05-19 22:15:47 -0600887 return -EPIPE;
Rusty Russell21206ed2010-01-18 19:15:00 +0530888
889 /* If we don't have an input queue yet, we can't get input. */
890 BUG_ON(!port->in_vq);
891
Amit Shahb766cee2009-12-21 21:26:45 +0530892 return fill_readbuf(port, buf, count, false);
Rusty Russell31610432007-10-22 11:03:39 +1000893}
Rusty Russell31610432007-10-22 11:03:39 +1000894
Amit Shahcb06e362010-01-18 19:15:08 +0530895static void resize_console(struct port *port)
Christian Borntraegerc2983452008-11-25 13:36:26 +0100896{
Amit Shahcb06e362010-01-18 19:15:08 +0530897 struct virtio_device *vdev;
Christian Borntraegerc2983452008-11-25 13:36:26 +0100898
Amit Shah2de16a42010-03-19 17:36:44 +0530899 /* The port could have been hot-unplugged */
Amit Shah97788292010-05-06 02:05:08 +0530900 if (!port || !is_console_port(port))
Amit Shah2de16a42010-03-19 17:36:44 +0530901 return;
902
Amit Shahcb06e362010-01-18 19:15:08 +0530903 vdev = port->portdev->vdev;
Amit Shah97788292010-05-06 02:05:08 +0530904 if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE))
905 hvc_resize(port->cons.hvc, port->cons.ws);
Christian Borntraegerc2983452008-11-25 13:36:26 +0100906}
907
Amit Shah38edf582010-01-18 19:15:05 +0530908/* We set the configuration at this point, since we now have a tty */
Christian Borntraeger91fcad12008-06-20 15:24:15 +0200909static int notifier_add_vio(struct hvc_struct *hp, int data)
910{
Amit Shah38edf582010-01-18 19:15:05 +0530911 struct port *port;
912
913 port = find_port_by_vtermno(hp->vtermno);
914 if (!port)
915 return -EINVAL;
916
Christian Borntraeger91fcad12008-06-20 15:24:15 +0200917 hp->irq_requested = 1;
Amit Shahcb06e362010-01-18 19:15:08 +0530918 resize_console(port);
Christian Borntraegerc2983452008-11-25 13:36:26 +0100919
Christian Borntraeger91fcad12008-06-20 15:24:15 +0200920 return 0;
921}
922
923static void notifier_del_vio(struct hvc_struct *hp, int data)
924{
925 hp->irq_requested = 0;
926}
927
Amit Shah17634ba2009-12-21 21:03:25 +0530928/* The operations for console ports. */
Rusty Russell1dff3992009-11-28 12:20:26 +0530929static const struct hv_ops hv_ops = {
Rusty Russell971f3392010-01-18 19:14:56 +0530930 .get_chars = get_chars,
931 .put_chars = put_chars,
932 .notifier_add = notifier_add_vio,
933 .notifier_del = notifier_del_vio,
934 .notifier_hangup = notifier_del_vio,
935};
936
937/*
938 * Console drivers are initialized very early so boot messages can go
939 * out, so we do things slightly differently from the generic virtio
940 * initialization of the net and block drivers.
941 *
942 * At this stage, the console is output-only. It's too early to set
943 * up a virtqueue, so we let the drivers do some boutique early-output
944 * thing.
945 */
946int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
947{
948 early_put_chars = put_chars;
949 return hvc_instantiate(0, 0, &hv_ops);
950}
951
Amit Shah17634ba2009-12-21 21:03:25 +0530952int init_port_console(struct port *port)
Amit Shahcfa6d372010-01-18 19:15:10 +0530953{
954 int ret;
955
956 /*
957 * The Host's telling us this port is a console port. Hook it
958 * up with an hvc console.
959 *
960 * To set up and manage our virtual console, we call
961 * hvc_alloc().
962 *
963 * The first argument of hvc_alloc() is the virtual console
964 * number. The second argument is the parameter for the
965 * notification mechanism (like irq number). We currently
966 * leave this as zero, virtqueues have implicit notifications.
967 *
968 * The third argument is a "struct hv_ops" containing the
969 * put_chars() get_chars(), notifier_add() and notifier_del()
970 * pointers. The final argument is the output buffer size: we
971 * can do any size, so we put PAGE_SIZE here.
972 */
973 port->cons.vtermno = pdrvdata.next_vtermno;
974
975 port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE);
976 if (IS_ERR(port->cons.hvc)) {
977 ret = PTR_ERR(port->cons.hvc);
Amit Shah298add72010-01-18 16:35:23 +0530978 dev_err(port->dev,
979 "error %d allocating hvc for port\n", ret);
Amit Shahcfa6d372010-01-18 19:15:10 +0530980 port->cons.hvc = NULL;
981 return ret;
982 }
983 spin_lock_irq(&pdrvdata_lock);
984 pdrvdata.next_vtermno++;
985 list_add_tail(&port->cons.list, &pdrvdata.consoles);
986 spin_unlock_irq(&pdrvdata_lock);
Amit Shah3c7969c2009-11-26 11:25:38 +0530987 port->guest_connected = true;
Amit Shahcfa6d372010-01-18 19:15:10 +0530988
Amit Shah1d051602010-05-19 22:15:49 -0600989 /*
990 * Start using the new console output if this is the first
991 * console to come up.
992 */
993 if (early_put_chars)
994 early_put_chars = NULL;
995
Amit Shah2030fa42009-12-21 21:49:30 +0530996 /* Notify host of port being opened */
997 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
998
Amit Shahcfa6d372010-01-18 19:15:10 +0530999 return 0;
1000}
1001
Amit Shah431edb82009-12-21 21:57:40 +05301002static ssize_t show_port_name(struct device *dev,
1003 struct device_attribute *attr, char *buffer)
1004{
1005 struct port *port;
1006
1007 port = dev_get_drvdata(dev);
1008
1009 return sprintf(buffer, "%s\n", port->name);
1010}
1011
1012static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL);
1013
1014static struct attribute *port_sysfs_entries[] = {
1015 &dev_attr_name.attr,
1016 NULL
1017};
1018
1019static struct attribute_group port_attribute_group = {
1020 .name = NULL, /* put in device directory */
1021 .attrs = port_sysfs_entries,
1022};
1023
Amit Shahd99393e2009-12-21 22:36:21 +05301024static int debugfs_open(struct inode *inode, struct file *filp)
1025{
1026 filp->private_data = inode->i_private;
1027 return 0;
1028}
1029
1030static ssize_t debugfs_read(struct file *filp, char __user *ubuf,
1031 size_t count, loff_t *offp)
1032{
1033 struct port *port;
1034 char *buf;
1035 ssize_t ret, out_offset, out_count;
1036
1037 out_count = 1024;
1038 buf = kmalloc(out_count, GFP_KERNEL);
1039 if (!buf)
1040 return -ENOMEM;
1041
1042 port = filp->private_data;
1043 out_offset = 0;
1044 out_offset += snprintf(buf + out_offset, out_count,
1045 "name: %s\n", port->name ? port->name : "");
1046 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1047 "guest_connected: %d\n", port->guest_connected);
1048 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1049 "host_connected: %d\n", port->host_connected);
1050 out_offset += snprintf(buf + out_offset, out_count - out_offset,
Amit Shahcdfadfc2010-05-19 22:15:50 -06001051 "outvq_full: %d\n", port->outvq_full);
1052 out_offset += snprintf(buf + out_offset, out_count - out_offset,
Amit Shahd99393e2009-12-21 22:36:21 +05301053 "is_console: %s\n",
1054 is_console_port(port) ? "yes" : "no");
1055 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1056 "console_vtermno: %u\n", port->cons.vtermno);
1057
1058 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
1059 kfree(buf);
1060 return ret;
1061}
1062
1063static const struct file_operations port_debugfs_ops = {
1064 .owner = THIS_MODULE,
1065 .open = debugfs_open,
1066 .read = debugfs_read,
1067};
1068
Amit Shah97788292010-05-06 02:05:08 +05301069static void set_console_size(struct port *port, u16 rows, u16 cols)
1070{
1071 if (!port || !is_console_port(port))
1072 return;
1073
1074 port->cons.ws.ws_row = rows;
1075 port->cons.ws.ws_col = cols;
1076}
1077
Amit Shahc446f8f2010-05-19 22:15:48 -06001078static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
1079{
1080 struct port_buffer *buf;
1081 unsigned int nr_added_bufs;
1082 int ret;
1083
1084 nr_added_bufs = 0;
1085 do {
1086 buf = alloc_buf(PAGE_SIZE);
1087 if (!buf)
1088 break;
1089
1090 spin_lock_irq(lock);
1091 ret = add_inbuf(vq, buf);
1092 if (ret < 0) {
1093 spin_unlock_irq(lock);
1094 free_buf(buf);
1095 break;
1096 }
1097 nr_added_bufs++;
1098 spin_unlock_irq(lock);
1099 } while (ret > 0);
1100
1101 return nr_added_bufs;
1102}
1103
Amit Shah3eae0ad2010-09-02 18:47:52 +05301104static void send_sigio_to_port(struct port *port)
1105{
1106 if (port->async_queue && port->guest_connected)
1107 kill_fasync(&port->async_queue, SIGIO, POLL_OUT);
1108}
1109
Amit Shahc446f8f2010-05-19 22:15:48 -06001110static int add_port(struct ports_device *portdev, u32 id)
1111{
1112 char debugfs_name[16];
1113 struct port *port;
1114 struct port_buffer *buf;
1115 dev_t devt;
1116 unsigned int nr_added_bufs;
1117 int err;
1118
1119 port = kmalloc(sizeof(*port), GFP_KERNEL);
1120 if (!port) {
1121 err = -ENOMEM;
1122 goto fail;
1123 }
Amit Shahb353a6b2010-09-02 18:38:29 +05301124 kref_init(&port->kref);
Amit Shahc446f8f2010-05-19 22:15:48 -06001125
1126 port->portdev = portdev;
1127 port->id = id;
1128
1129 port->name = NULL;
1130 port->inbuf = NULL;
1131 port->cons.hvc = NULL;
Amit Shah3eae0ad2010-09-02 18:47:52 +05301132 port->async_queue = NULL;
Amit Shahc446f8f2010-05-19 22:15:48 -06001133
Amit Shah97788292010-05-06 02:05:08 +05301134 port->cons.ws.ws_row = port->cons.ws.ws_col = 0;
1135
Amit Shahc446f8f2010-05-19 22:15:48 -06001136 port->host_connected = port->guest_connected = false;
1137
Amit Shahcdfadfc2010-05-19 22:15:50 -06001138 port->outvq_full = false;
1139
Amit Shahc446f8f2010-05-19 22:15:48 -06001140 port->in_vq = portdev->in_vqs[port->id];
1141 port->out_vq = portdev->out_vqs[port->id];
1142
Amit Shahd22a6982010-09-02 18:20:59 +05301143 port->cdev = cdev_alloc();
1144 if (!port->cdev) {
1145 dev_err(&port->portdev->vdev->dev, "Error allocating cdev\n");
1146 err = -ENOMEM;
1147 goto free_port;
1148 }
1149 port->cdev->ops = &port_fops;
Amit Shahc446f8f2010-05-19 22:15:48 -06001150
1151 devt = MKDEV(portdev->chr_major, id);
Amit Shahd22a6982010-09-02 18:20:59 +05301152 err = cdev_add(port->cdev, devt, 1);
Amit Shahc446f8f2010-05-19 22:15:48 -06001153 if (err < 0) {
1154 dev_err(&port->portdev->vdev->dev,
1155 "Error %d adding cdev for port %u\n", err, id);
Amit Shahd22a6982010-09-02 18:20:59 +05301156 goto free_cdev;
Amit Shahc446f8f2010-05-19 22:15:48 -06001157 }
1158 port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
1159 devt, port, "vport%up%u",
1160 port->portdev->drv_index, id);
1161 if (IS_ERR(port->dev)) {
1162 err = PTR_ERR(port->dev);
1163 dev_err(&port->portdev->vdev->dev,
1164 "Error %d creating device for port %u\n",
1165 err, id);
1166 goto free_cdev;
1167 }
1168
1169 spin_lock_init(&port->inbuf_lock);
Amit Shahcdfadfc2010-05-19 22:15:50 -06001170 spin_lock_init(&port->outvq_lock);
Amit Shahc446f8f2010-05-19 22:15:48 -06001171 init_waitqueue_head(&port->waitqueue);
1172
1173 /* Fill the in_vq with buffers so the host can send us data. */
1174 nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock);
1175 if (!nr_added_bufs) {
1176 dev_err(port->dev, "Error allocating inbufs\n");
1177 err = -ENOMEM;
1178 goto free_device;
1179 }
1180
1181 /*
1182 * If we're not using multiport support, this has to be a console port
1183 */
1184 if (!use_multiport(port->portdev)) {
1185 err = init_port_console(port);
1186 if (err)
1187 goto free_inbufs;
1188 }
1189
1190 spin_lock_irq(&portdev->ports_lock);
1191 list_add_tail(&port->list, &port->portdev->ports);
1192 spin_unlock_irq(&portdev->ports_lock);
1193
1194 /*
1195 * Tell the Host we're set so that it can send us various
1196 * configuration parameters for this port (eg, port name,
1197 * caching, whether this is a console port, etc.)
1198 */
1199 send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
1200
1201 if (pdrvdata.debugfs_dir) {
1202 /*
1203 * Finally, create the debugfs file that we can use to
1204 * inspect a port's state at any time
1205 */
1206 sprintf(debugfs_name, "vport%up%u",
1207 port->portdev->drv_index, id);
1208 port->debugfs_file = debugfs_create_file(debugfs_name, 0444,
1209 pdrvdata.debugfs_dir,
1210 port,
1211 &port_debugfs_ops);
1212 }
1213 return 0;
1214
1215free_inbufs:
1216 while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
1217 free_buf(buf);
1218free_device:
1219 device_destroy(pdrvdata.class, port->dev->devt);
1220free_cdev:
Amit Shahd22a6982010-09-02 18:20:59 +05301221 cdev_del(port->cdev);
Amit Shahc446f8f2010-05-19 22:15:48 -06001222free_port:
1223 kfree(port);
1224fail:
1225 /* The host might want to notify management sw about port add failure */
Julia Lawall0643e4c2010-05-15 11:45:53 +02001226 __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0);
Amit Shahc446f8f2010-05-19 22:15:48 -06001227 return err;
1228}
1229
Amit Shahb353a6b2010-09-02 18:38:29 +05301230/* No users remain, remove all port-specific data. */
1231static void remove_port(struct kref *kref)
1232{
1233 struct port *port;
1234
1235 port = container_of(kref, struct port, kref);
1236
1237 sysfs_remove_group(&port->dev->kobj, &port_attribute_group);
1238 device_destroy(pdrvdata.class, port->dev->devt);
1239 cdev_del(port->cdev);
1240
1241 kfree(port->name);
1242
1243 debugfs_remove(port->debugfs_file);
1244
1245 kfree(port);
1246}
1247
1248/*
1249 * Port got unplugged. Remove port from portdev's list and drop the
1250 * kref reference. If no userspace has this port opened, it will
1251 * result in immediate removal the port.
1252 */
1253static void unplug_port(struct port *port)
Amit Shah1f7aa422009-12-21 22:27:31 +05301254{
Amit Shaha9cdd482010-02-12 10:32:15 +05301255 struct port_buffer *buf;
1256
Amit Shahb353a6b2010-09-02 18:38:29 +05301257 spin_lock_irq(&port->portdev->ports_lock);
1258 list_del(&port->list);
1259 spin_unlock_irq(&port->portdev->ports_lock);
1260
Amit Shah00476342010-05-27 13:24:39 +05301261 if (port->guest_connected) {
1262 port->guest_connected = false;
1263 port->host_connected = false;
1264 wake_up_interruptible(&port->waitqueue);
Amit Shaha461e112010-09-02 18:47:54 +05301265
1266 /* Let the app know the port is going down. */
1267 send_sigio_to_port(port);
Amit Shah00476342010-05-27 13:24:39 +05301268 }
1269
Amit Shah1f7aa422009-12-21 22:27:31 +05301270 if (is_console_port(port)) {
1271 spin_lock_irq(&pdrvdata_lock);
1272 list_del(&port->cons.list);
1273 spin_unlock_irq(&pdrvdata_lock);
Amit Shah69eb9a92010-05-19 22:15:47 -06001274#if 0
1275 /*
1276 * hvc_remove() not called as removing one hvc port
1277 * results in other hvc ports getting frozen.
1278 *
1279 * Once this is resolved in hvc, this functionality
1280 * will be enabled. Till that is done, the -EPIPE
1281 * return from get_chars() above will help
1282 * hvc_console.c to clean up on ports we remove here.
1283 */
Amit Shah1f7aa422009-12-21 22:27:31 +05301284 hvc_remove(port->cons.hvc);
Amit Shah69eb9a92010-05-19 22:15:47 -06001285#endif
Amit Shah1f7aa422009-12-21 22:27:31 +05301286 }
Amit Shah1f7aa422009-12-21 22:27:31 +05301287
Amit Shaha9cdd482010-02-12 10:32:15 +05301288 /* Remove unused data this port might have received. */
Amit Shah1f7aa422009-12-21 22:27:31 +05301289 discard_port_data(port);
Amit Shaha9cdd482010-02-12 10:32:15 +05301290
Amit Shahcdfadfc2010-05-19 22:15:50 -06001291 reclaim_consumed_buffers(port);
1292
Amit Shaha9cdd482010-02-12 10:32:15 +05301293 /* Remove buffers we queued up for the Host to send us data in. */
Michael S. Tsirkin505b0452010-04-12 16:18:32 +03001294 while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
Amit Shaha9cdd482010-02-12 10:32:15 +05301295 free_buf(buf);
1296
Amit Shahb353a6b2010-09-02 18:38:29 +05301297 /*
1298 * We should just assume the device itself has gone off --
1299 * else a close on an open port later will try to send out a
1300 * control message.
1301 */
1302 port->portdev = NULL;
Amit Shah1f7aa422009-12-21 22:27:31 +05301303
Amit Shahb353a6b2010-09-02 18:38:29 +05301304 /*
1305 * Locks around here are not necessary - a port can't be
1306 * opened after we removed the port struct from ports_list
1307 * above.
1308 */
1309 kref_put(&port->kref, remove_port);
Amit Shah1f7aa422009-12-21 22:27:31 +05301310}
1311
Amit Shah17634ba2009-12-21 21:03:25 +05301312/* Any private messages that the Host and Guest want to share */
1313static void handle_control_message(struct ports_device *portdev,
1314 struct port_buffer *buf)
1315{
1316 struct virtio_console_control *cpkt;
1317 struct port *port;
Amit Shah431edb82009-12-21 21:57:40 +05301318 size_t name_size;
1319 int err;
Amit Shah17634ba2009-12-21 21:03:25 +05301320
1321 cpkt = (struct virtio_console_control *)(buf->buf + buf->offset);
1322
1323 port = find_port_by_id(portdev, cpkt->id);
Amit Shahf909f852010-05-19 22:15:48 -06001324 if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) {
Amit Shah17634ba2009-12-21 21:03:25 +05301325 /* No valid header at start of buffer. Drop it. */
1326 dev_dbg(&portdev->vdev->dev,
1327 "Invalid index %u in control packet\n", cpkt->id);
1328 return;
1329 }
1330
1331 switch (cpkt->event) {
Amit Shahf909f852010-05-19 22:15:48 -06001332 case VIRTIO_CONSOLE_PORT_ADD:
1333 if (port) {
Amit Shah1d051602010-05-19 22:15:49 -06001334 dev_dbg(&portdev->vdev->dev,
1335 "Port %u already added\n", port->id);
Amit Shahf909f852010-05-19 22:15:48 -06001336 send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
1337 break;
1338 }
1339 if (cpkt->id >= portdev->config.max_nr_ports) {
1340 dev_warn(&portdev->vdev->dev,
1341 "Request for adding port with out-of-bound id %u, max. supported id: %u\n",
1342 cpkt->id, portdev->config.max_nr_ports - 1);
1343 break;
1344 }
1345 add_port(portdev, cpkt->id);
1346 break;
1347 case VIRTIO_CONSOLE_PORT_REMOVE:
Amit Shahb353a6b2010-09-02 18:38:29 +05301348 unplug_port(port);
Amit Shahf909f852010-05-19 22:15:48 -06001349 break;
Amit Shah17634ba2009-12-21 21:03:25 +05301350 case VIRTIO_CONSOLE_CONSOLE_PORT:
1351 if (!cpkt->value)
1352 break;
1353 if (is_console_port(port))
1354 break;
1355
1356 init_port_console(port);
1357 /*
1358 * Could remove the port here in case init fails - but
1359 * have to notify the host first.
1360 */
1361 break;
Amit Shah8345adb2010-05-06 02:05:09 +05301362 case VIRTIO_CONSOLE_RESIZE: {
1363 struct {
1364 __u16 rows;
1365 __u16 cols;
1366 } size;
1367
Amit Shah17634ba2009-12-21 21:03:25 +05301368 if (!is_console_port(port))
1369 break;
Amit Shah8345adb2010-05-06 02:05:09 +05301370
1371 memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt),
1372 sizeof(size));
1373 set_console_size(port, size.rows, size.cols);
1374
Amit Shah17634ba2009-12-21 21:03:25 +05301375 port->cons.hvc->irq_requested = 1;
1376 resize_console(port);
1377 break;
Amit Shah8345adb2010-05-06 02:05:09 +05301378 }
Amit Shah2030fa42009-12-21 21:49:30 +05301379 case VIRTIO_CONSOLE_PORT_OPEN:
1380 port->host_connected = cpkt->value;
1381 wake_up_interruptible(&port->waitqueue);
Amit Shahcdfadfc2010-05-19 22:15:50 -06001382 /*
1383 * If the host port got closed and the host had any
1384 * unconsumed buffers, we'll be able to reclaim them
1385 * now.
1386 */
1387 spin_lock_irq(&port->outvq_lock);
1388 reclaim_consumed_buffers(port);
1389 spin_unlock_irq(&port->outvq_lock);
Amit Shah3eae0ad2010-09-02 18:47:52 +05301390
1391 /*
1392 * If the guest is connected, it'll be interested in
1393 * knowing the host connection state changed.
1394 */
1395 send_sigio_to_port(port);
Amit Shah2030fa42009-12-21 21:49:30 +05301396 break;
Amit Shah431edb82009-12-21 21:57:40 +05301397 case VIRTIO_CONSOLE_PORT_NAME:
1398 /*
1399 * Skip the size of the header and the cpkt to get the size
1400 * of the name that was sent
1401 */
1402 name_size = buf->len - buf->offset - sizeof(*cpkt) + 1;
1403
1404 port->name = kmalloc(name_size, GFP_KERNEL);
1405 if (!port->name) {
1406 dev_err(port->dev,
1407 "Not enough space to store port name\n");
1408 break;
1409 }
1410 strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt),
1411 name_size - 1);
1412 port->name[name_size - 1] = 0;
1413
1414 /*
1415 * Since we only have one sysfs attribute, 'name',
1416 * create it only if we have a name for the port.
1417 */
1418 err = sysfs_create_group(&port->dev->kobj,
1419 &port_attribute_group);
Amit Shahec642132010-03-19 17:36:43 +05301420 if (err) {
Amit Shah431edb82009-12-21 21:57:40 +05301421 dev_err(port->dev,
1422 "Error %d creating sysfs device attributes\n",
1423 err);
Amit Shahec642132010-03-19 17:36:43 +05301424 } else {
1425 /*
1426 * Generate a udev event so that appropriate
1427 * symlinks can be created based on udev
1428 * rules.
1429 */
1430 kobject_uevent(&port->dev->kobj, KOBJ_CHANGE);
1431 }
Amit Shah431edb82009-12-21 21:57:40 +05301432 break;
Amit Shah17634ba2009-12-21 21:03:25 +05301433 }
1434}
1435
1436static void control_work_handler(struct work_struct *work)
1437{
1438 struct ports_device *portdev;
1439 struct virtqueue *vq;
1440 struct port_buffer *buf;
1441 unsigned int len;
1442
1443 portdev = container_of(work, struct ports_device, control_work);
1444 vq = portdev->c_ivq;
1445
1446 spin_lock(&portdev->cvq_lock);
Michael S. Tsirkin505b0452010-04-12 16:18:32 +03001447 while ((buf = virtqueue_get_buf(vq, &len))) {
Amit Shah17634ba2009-12-21 21:03:25 +05301448 spin_unlock(&portdev->cvq_lock);
1449
1450 buf->len = len;
1451 buf->offset = 0;
1452
1453 handle_control_message(portdev, buf);
1454
1455 spin_lock(&portdev->cvq_lock);
1456 if (add_inbuf(portdev->c_ivq, buf) < 0) {
1457 dev_warn(&portdev->vdev->dev,
1458 "Error adding buffer to queue\n");
1459 free_buf(buf);
1460 }
1461 }
1462 spin_unlock(&portdev->cvq_lock);
1463}
1464
1465static void in_intr(struct virtqueue *vq)
1466{
1467 struct port *port;
1468 unsigned long flags;
1469
1470 port = find_port_by_vq(vq->vdev->priv, vq);
1471 if (!port)
1472 return;
1473
1474 spin_lock_irqsave(&port->inbuf_lock, flags);
Amit Shahd6933562010-02-12 10:32:18 +05301475 if (!port->inbuf)
1476 port->inbuf = get_inbuf(port);
Amit Shah17634ba2009-12-21 21:03:25 +05301477
Amit Shah88f251a2009-12-21 22:15:30 +05301478 /*
1479 * Don't queue up data when port is closed. This condition
1480 * can be reached when a console port is not yet connected (no
1481 * tty is spawned) and the host sends out data to console
1482 * ports. For generic serial ports, the host won't
1483 * (shouldn't) send data till the guest is connected.
1484 */
1485 if (!port->guest_connected)
1486 discard_port_data(port);
1487
Amit Shah17634ba2009-12-21 21:03:25 +05301488 spin_unlock_irqrestore(&port->inbuf_lock, flags);
1489
Amit Shah2030fa42009-12-21 21:49:30 +05301490 wake_up_interruptible(&port->waitqueue);
1491
Amit Shah55f6bcc2010-09-02 18:47:53 +05301492 /* Send a SIGIO indicating new data in case the process asked for it */
1493 send_sigio_to_port(port);
1494
Amit Shah17634ba2009-12-21 21:03:25 +05301495 if (is_console_port(port) && hvc_poll(port->cons.hvc))
1496 hvc_kick();
1497}
1498
1499static void control_intr(struct virtqueue *vq)
1500{
1501 struct ports_device *portdev;
1502
1503 portdev = vq->vdev->priv;
1504 schedule_work(&portdev->control_work);
1505}
1506
Amit Shah7f5d8102009-12-21 22:22:08 +05301507static void config_intr(struct virtio_device *vdev)
1508{
1509 struct ports_device *portdev;
1510
1511 portdev = vdev->priv;
Amit Shah99f905f2010-05-19 22:15:48 -06001512
Amit Shah4038f5b72010-05-06 02:05:07 +05301513 if (!use_multiport(portdev)) {
Amit Shah97788292010-05-06 02:05:08 +05301514 struct port *port;
1515 u16 rows, cols;
1516
1517 vdev->config->get(vdev,
1518 offsetof(struct virtio_console_config, cols),
1519 &cols, sizeof(u16));
1520 vdev->config->get(vdev,
1521 offsetof(struct virtio_console_config, rows),
1522 &rows, sizeof(u16));
1523
1524 port = find_port_by_id(portdev, 0);
1525 set_console_size(port, rows, cols);
1526
Amit Shah4038f5b72010-05-06 02:05:07 +05301527 /*
1528 * We'll use this way of resizing only for legacy
1529 * support. For newer userspace
1530 * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages
1531 * to indicate console size changes so that it can be
1532 * done per-port.
1533 */
Amit Shah97788292010-05-06 02:05:08 +05301534 resize_console(port);
Amit Shah4038f5b72010-05-06 02:05:07 +05301535 }
Amit Shah7f5d8102009-12-21 22:22:08 +05301536}
1537
Amit Shah2658a79a2010-01-18 19:15:11 +05301538static int init_vqs(struct ports_device *portdev)
1539{
1540 vq_callback_t **io_callbacks;
1541 char **io_names;
1542 struct virtqueue **vqs;
Amit Shah17634ba2009-12-21 21:03:25 +05301543 u32 i, j, nr_ports, nr_queues;
Amit Shah2658a79a2010-01-18 19:15:11 +05301544 int err;
1545
Amit Shah17634ba2009-12-21 21:03:25 +05301546 nr_ports = portdev->config.max_nr_ports;
1547 nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2;
Amit Shah2658a79a2010-01-18 19:15:11 +05301548
1549 vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL);
1550 if (!vqs) {
1551 err = -ENOMEM;
1552 goto fail;
1553 }
1554 io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL);
1555 if (!io_callbacks) {
1556 err = -ENOMEM;
1557 goto free_vqs;
1558 }
1559 io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL);
1560 if (!io_names) {
1561 err = -ENOMEM;
1562 goto free_callbacks;
1563 }
1564 portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
1565 GFP_KERNEL);
1566 if (!portdev->in_vqs) {
1567 err = -ENOMEM;
1568 goto free_names;
1569 }
1570 portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
1571 GFP_KERNEL);
1572 if (!portdev->out_vqs) {
1573 err = -ENOMEM;
1574 goto free_invqs;
1575 }
1576
Amit Shah17634ba2009-12-21 21:03:25 +05301577 /*
1578 * For backward compat (newer host but older guest), the host
1579 * spawns a console port first and also inits the vqs for port
1580 * 0 before others.
1581 */
1582 j = 0;
1583 io_callbacks[j] = in_intr;
1584 io_callbacks[j + 1] = NULL;
1585 io_names[j] = "input";
1586 io_names[j + 1] = "output";
1587 j += 2;
Amit Shah2658a79a2010-01-18 19:15:11 +05301588
Amit Shah17634ba2009-12-21 21:03:25 +05301589 if (use_multiport(portdev)) {
1590 io_callbacks[j] = control_intr;
1591 io_callbacks[j + 1] = NULL;
1592 io_names[j] = "control-i";
1593 io_names[j + 1] = "control-o";
1594
1595 for (i = 1; i < nr_ports; i++) {
1596 j += 2;
1597 io_callbacks[j] = in_intr;
1598 io_callbacks[j + 1] = NULL;
1599 io_names[j] = "input";
1600 io_names[j + 1] = "output";
1601 }
1602 }
Amit Shah2658a79a2010-01-18 19:15:11 +05301603 /* Find the queues. */
1604 err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
1605 io_callbacks,
1606 (const char **)io_names);
1607 if (err)
1608 goto free_outvqs;
1609
Amit Shah17634ba2009-12-21 21:03:25 +05301610 j = 0;
Amit Shah2658a79a2010-01-18 19:15:11 +05301611 portdev->in_vqs[0] = vqs[0];
1612 portdev->out_vqs[0] = vqs[1];
Amit Shah17634ba2009-12-21 21:03:25 +05301613 j += 2;
1614 if (use_multiport(portdev)) {
1615 portdev->c_ivq = vqs[j];
1616 portdev->c_ovq = vqs[j + 1];
Amit Shah2658a79a2010-01-18 19:15:11 +05301617
Amit Shah17634ba2009-12-21 21:03:25 +05301618 for (i = 1; i < nr_ports; i++) {
1619 j += 2;
1620 portdev->in_vqs[i] = vqs[j];
1621 portdev->out_vqs[i] = vqs[j + 1];
1622 }
1623 }
Amit Shah2658a79a2010-01-18 19:15:11 +05301624 kfree(io_callbacks);
1625 kfree(io_names);
1626 kfree(vqs);
1627
1628 return 0;
1629
1630free_names:
1631 kfree(io_names);
1632free_callbacks:
1633 kfree(io_callbacks);
1634free_outvqs:
1635 kfree(portdev->out_vqs);
1636free_invqs:
1637 kfree(portdev->in_vqs);
1638free_vqs:
1639 kfree(vqs);
1640fail:
1641 return err;
1642}
1643
Amit Shahfb08bd22009-12-21 21:36:04 +05301644static const struct file_operations portdev_fops = {
1645 .owner = THIS_MODULE,
1646};
1647
Amit Shah1c85bf32010-01-18 19:15:07 +05301648/*
1649 * Once we're further in boot, we get probed like any other virtio
1650 * device.
Amit Shah17634ba2009-12-21 21:03:25 +05301651 *
1652 * If the host also supports multiple console ports, we check the
1653 * config space to see how many ports the host has spawned. We
1654 * initialize each port found.
Amit Shah1c85bf32010-01-18 19:15:07 +05301655 */
1656static int __devinit virtcons_probe(struct virtio_device *vdev)
1657{
Amit Shah1c85bf32010-01-18 19:15:07 +05301658 struct ports_device *portdev;
1659 int err;
Amit Shah17634ba2009-12-21 21:03:25 +05301660 bool multiport;
Amit Shah1c85bf32010-01-18 19:15:07 +05301661
1662 portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
1663 if (!portdev) {
1664 err = -ENOMEM;
1665 goto fail;
1666 }
1667
1668 /* Attach this portdev to this virtio_device, and vice-versa. */
1669 portdev->vdev = vdev;
1670 vdev->priv = portdev;
1671
Amit Shahfb08bd22009-12-21 21:36:04 +05301672 spin_lock_irq(&pdrvdata_lock);
1673 portdev->drv_index = pdrvdata.index++;
1674 spin_unlock_irq(&pdrvdata_lock);
1675
1676 portdev->chr_major = register_chrdev(0, "virtio-portsdev",
1677 &portdev_fops);
1678 if (portdev->chr_major < 0) {
1679 dev_err(&vdev->dev,
1680 "Error %d registering chrdev for device %u\n",
1681 portdev->chr_major, portdev->drv_index);
1682 err = portdev->chr_major;
1683 goto free;
1684 }
1685
Amit Shah17634ba2009-12-21 21:03:25 +05301686 multiport = false;
Amit Shah17634ba2009-12-21 21:03:25 +05301687 portdev->config.max_nr_ports = 1;
1688 if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
1689 multiport = true;
1690 vdev->features[0] |= 1 << VIRTIO_CONSOLE_F_MULTIPORT;
1691
Amit Shahb99fa812010-05-19 22:15:46 -06001692 vdev->config->get(vdev, offsetof(struct virtio_console_config,
Amit Shahb99fa812010-05-19 22:15:46 -06001693 max_nr_ports),
Amit Shah17634ba2009-12-21 21:03:25 +05301694 &portdev->config.max_nr_ports,
1695 sizeof(portdev->config.max_nr_ports));
Amit Shah17634ba2009-12-21 21:03:25 +05301696 }
1697
1698 /* Let the Host know we support multiple ports.*/
1699 vdev->config->finalize_features(vdev);
1700
Amit Shah2658a79a2010-01-18 19:15:11 +05301701 err = init_vqs(portdev);
1702 if (err < 0) {
1703 dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
Amit Shahfb08bd22009-12-21 21:36:04 +05301704 goto free_chrdev;
Amit Shah2658a79a2010-01-18 19:15:11 +05301705 }
Amit Shah1c85bf32010-01-18 19:15:07 +05301706
Amit Shah17634ba2009-12-21 21:03:25 +05301707 spin_lock_init(&portdev->ports_lock);
1708 INIT_LIST_HEAD(&portdev->ports);
1709
1710 if (multiport) {
Amit Shah335a64a5c2010-02-24 10:37:44 +05301711 unsigned int nr_added_bufs;
1712
Amit Shah17634ba2009-12-21 21:03:25 +05301713 spin_lock_init(&portdev->cvq_lock);
1714 INIT_WORK(&portdev->control_work, &control_work_handler);
1715
Amit Shah335a64a5c2010-02-24 10:37:44 +05301716 nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
1717 if (!nr_added_bufs) {
Amit Shah22a29ea2010-02-12 10:32:17 +05301718 dev_err(&vdev->dev,
1719 "Error allocating buffers for control queue\n");
1720 err = -ENOMEM;
1721 goto free_vqs;
1722 }
Amit Shah1d051602010-05-19 22:15:49 -06001723 } else {
1724 /*
1725 * For backward compatibility: Create a console port
1726 * if we're running on older host.
1727 */
1728 add_port(portdev, 0);
Amit Shah17634ba2009-12-21 21:03:25 +05301729 }
1730
Amit Shah6bdf2af2010-09-02 18:11:49 +05301731 spin_lock_irq(&pdrvdata_lock);
1732 list_add_tail(&portdev->list, &pdrvdata.portdevs);
1733 spin_unlock_irq(&pdrvdata_lock);
1734
Amit Shahf909f852010-05-19 22:15:48 -06001735 __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
1736 VIRTIO_CONSOLE_DEVICE_READY, 1);
Rusty Russell31610432007-10-22 11:03:39 +10001737 return 0;
1738
Amit Shah22a29ea2010-02-12 10:32:17 +05301739free_vqs:
Julia Lawall0643e4c2010-05-15 11:45:53 +02001740 /* The host might want to notify mgmt sw about device add failure */
1741 __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
1742 VIRTIO_CONSOLE_DEVICE_READY, 0);
Amit Shah22a29ea2010-02-12 10:32:17 +05301743 vdev->config->del_vqs(vdev);
1744 kfree(portdev->in_vqs);
1745 kfree(portdev->out_vqs);
Amit Shahfb08bd22009-12-21 21:36:04 +05301746free_chrdev:
1747 unregister_chrdev(portdev->chr_major, "virtio-portsdev");
Rusty Russell31610432007-10-22 11:03:39 +10001748free:
Amit Shah1c85bf32010-01-18 19:15:07 +05301749 kfree(portdev);
Rusty Russell31610432007-10-22 11:03:39 +10001750fail:
1751 return err;
1752}
1753
Amit Shah71778762010-02-12 10:32:16 +05301754static void virtcons_remove(struct virtio_device *vdev)
1755{
1756 struct ports_device *portdev;
1757 struct port *port, *port2;
Amit Shah71778762010-02-12 10:32:16 +05301758
1759 portdev = vdev->priv;
1760
Amit Shah6bdf2af2010-09-02 18:11:49 +05301761 spin_lock_irq(&pdrvdata_lock);
1762 list_del(&portdev->list);
1763 spin_unlock_irq(&pdrvdata_lock);
1764
Amit Shah02238952010-09-02 18:11:40 +05301765 /* Disable interrupts for vqs */
1766 vdev->config->reset(vdev);
1767 /* Finish up work that's lined up */
Amit Shah71778762010-02-12 10:32:16 +05301768 cancel_work_sync(&portdev->control_work);
Amit Shah71778762010-02-12 10:32:16 +05301769
1770 list_for_each_entry_safe(port, port2, &portdev->ports, list)
Amit Shahb353a6b2010-09-02 18:38:29 +05301771 unplug_port(port);
Amit Shah71778762010-02-12 10:32:16 +05301772
1773 unregister_chrdev(portdev->chr_major, "virtio-portsdev");
1774
Amit Shahe0620132010-09-02 18:38:30 +05301775 /*
1776 * When yanking out a device, we immediately lose the
1777 * (device-side) queues. So there's no point in keeping the
1778 * guest side around till we drop our final reference. This
1779 * also means that any ports which are in an open state will
1780 * have to just stop using the port, as the vqs are going
1781 * away.
1782 */
Amit Shah96eb8722010-09-02 18:11:41 +05301783 if (use_multiport(portdev)) {
1784 struct port_buffer *buf;
1785 unsigned int len;
Amit Shah71778762010-02-12 10:32:16 +05301786
Amit Shah96eb8722010-09-02 18:11:41 +05301787 while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
1788 free_buf(buf);
1789
1790 while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
1791 free_buf(buf);
1792 }
Amit Shah71778762010-02-12 10:32:16 +05301793
1794 vdev->config->del_vqs(vdev);
1795 kfree(portdev->in_vqs);
1796 kfree(portdev->out_vqs);
1797
1798 kfree(portdev);
1799}
1800
Rusty Russell31610432007-10-22 11:03:39 +10001801static struct virtio_device_id id_table[] = {
1802 { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID },
1803 { 0 },
1804};
1805
Christian Borntraegerc2983452008-11-25 13:36:26 +01001806static unsigned int features[] = {
1807 VIRTIO_CONSOLE_F_SIZE,
Amit Shahb99fa812010-05-19 22:15:46 -06001808 VIRTIO_CONSOLE_F_MULTIPORT,
Christian Borntraegerc2983452008-11-25 13:36:26 +01001809};
1810
Rusty Russell31610432007-10-22 11:03:39 +10001811static struct virtio_driver virtio_console = {
Christian Borntraegerc2983452008-11-25 13:36:26 +01001812 .feature_table = features,
1813 .feature_table_size = ARRAY_SIZE(features),
Rusty Russell31610432007-10-22 11:03:39 +10001814 .driver.name = KBUILD_MODNAME,
1815 .driver.owner = THIS_MODULE,
1816 .id_table = id_table,
1817 .probe = virtcons_probe,
Amit Shah71778762010-02-12 10:32:16 +05301818 .remove = virtcons_remove,
Amit Shah7f5d8102009-12-21 22:22:08 +05301819 .config_changed = config_intr,
Rusty Russell31610432007-10-22 11:03:39 +10001820};
1821
1822static int __init init(void)
1823{
Amit Shahfb08bd22009-12-21 21:36:04 +05301824 int err;
1825
1826 pdrvdata.class = class_create(THIS_MODULE, "virtio-ports");
1827 if (IS_ERR(pdrvdata.class)) {
1828 err = PTR_ERR(pdrvdata.class);
1829 pr_err("Error %d creating virtio-ports class\n", err);
1830 return err;
1831 }
Amit Shahd99393e2009-12-21 22:36:21 +05301832
1833 pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL);
1834 if (!pdrvdata.debugfs_dir) {
1835 pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
1836 PTR_ERR(pdrvdata.debugfs_dir));
1837 }
Amit Shah38edf582010-01-18 19:15:05 +05301838 INIT_LIST_HEAD(&pdrvdata.consoles);
Amit Shah6bdf2af2010-09-02 18:11:49 +05301839 INIT_LIST_HEAD(&pdrvdata.portdevs);
Amit Shah38edf582010-01-18 19:15:05 +05301840
Rusty Russell31610432007-10-22 11:03:39 +10001841 return register_virtio_driver(&virtio_console);
1842}
Amit Shah71778762010-02-12 10:32:16 +05301843
1844static void __exit fini(void)
1845{
1846 unregister_virtio_driver(&virtio_console);
1847
1848 class_destroy(pdrvdata.class);
1849 if (pdrvdata.debugfs_dir)
1850 debugfs_remove_recursive(pdrvdata.debugfs_dir);
1851}
Rusty Russell31610432007-10-22 11:03:39 +10001852module_init(init);
Amit Shah71778762010-02-12 10:32:16 +05301853module_exit(fini);
Rusty Russell31610432007-10-22 11:03:39 +10001854
1855MODULE_DEVICE_TABLE(virtio, id_table);
1856MODULE_DESCRIPTION("Virtio console driver");
1857MODULE_LICENSE("GPL");