Commit | Line | Data |
---|---|---|
a23ea924 RR |
1 | /* |
2 | * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation | |
17634ba2 | 3 | * Copyright (C) 2009, 2010 Red Hat, Inc. |
31610434 RR |
4 | * |
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 | */ | |
fb08bd27 | 19 | #include <linux/cdev.h> |
d99393ef | 20 | #include <linux/debugfs.h> |
fb08bd27 | 21 | #include <linux/device.h> |
31610434 | 22 | #include <linux/err.h> |
2030fa49 | 23 | #include <linux/fs.h> |
31610434 | 24 | #include <linux/init.h> |
38edf58d | 25 | #include <linux/list.h> |
2030fa49 AS |
26 | #include <linux/poll.h> |
27 | #include <linux/sched.h> | |
5a0e3ad6 | 28 | #include <linux/slab.h> |
38edf58d | 29 | #include <linux/spinlock.h> |
31610434 RR |
30 | #include <linux/virtio.h> |
31 | #include <linux/virtio_console.h> | |
2030fa49 | 32 | #include <linux/wait.h> |
17634ba2 | 33 | #include <linux/workqueue.h> |
31610434 RR |
34 | #include "hvc_console.h" |
35 | ||
38edf58d AS |
36 | /* |
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 | */ | |
44 | struct ports_driver_data { | |
fb08bd27 AS |
45 | /* Used for registering chardevs */ |
46 | struct class *class; | |
47 | ||
d99393ef AS |
48 | /* Used for exporting per-port information to debugfs */ |
49 | struct dentry *debugfs_dir; | |
50 | ||
fb08bd27 AS |
51 | /* Number of devices this driver is handling */ |
52 | unsigned int index; | |
53 | ||
d8a02bd5 RR |
54 | /* |
55 | * This is used to keep track of the number of hvc consoles | |
56 | * spawned by this driver. This number is given as the first | |
57 | * argument to hvc_alloc(). To correctly map an initial | |
58 | * console spawned via hvc_instantiate to the console being | |
59 | * hooked up via hvc_alloc, we need to pass the same vtermno. | |
60 | * | |
61 | * We also just assume the first console being initialised was | |
62 | * the first one that got used as the initial console. | |
63 | */ | |
64 | unsigned int next_vtermno; | |
65 | ||
38edf58d AS |
66 | /* All the console devices handled by this driver */ |
67 | struct list_head consoles; | |
68 | }; | |
69 | static struct ports_driver_data pdrvdata; | |
70 | ||
71 | DEFINE_SPINLOCK(pdrvdata_lock); | |
72 | ||
4f23c573 AS |
73 | /* This struct holds information that's relevant only for console ports */ |
74 | struct console { | |
75 | /* We'll place all consoles in a list in the pdrvdata struct */ | |
76 | struct list_head list; | |
77 | ||
78 | /* The hvc device associated with this console port */ | |
79 | struct hvc_struct *hvc; | |
80 | ||
9778829c AS |
81 | /* The size of the console */ |
82 | struct winsize ws; | |
83 | ||
4f23c573 AS |
84 | /* |
85 | * This number identifies the number that we used to register | |
86 | * with hvc in hvc_instantiate() and hvc_alloc(); this is the | |
87 | * number passed on by the hvc callbacks to us to | |
88 | * differentiate between the other console ports handled by | |
89 | * this driver | |
90 | */ | |
91 | u32 vtermno; | |
92 | }; | |
93 | ||
fdb9a054 AS |
94 | struct port_buffer { |
95 | char *buf; | |
96 | ||
97 | /* size of the buffer in *buf above */ | |
98 | size_t size; | |
99 | ||
100 | /* used length of the buffer */ | |
101 | size_t len; | |
102 | /* offset in the buf from which to consume data */ | |
103 | size_t offset; | |
104 | }; | |
105 | ||
17634ba2 AS |
106 | /* |
107 | * This is a per-device struct that stores data common to all the | |
108 | * ports for that device (vdev->priv). | |
109 | */ | |
110 | struct ports_device { | |
111 | /* | |
112 | * Workqueue handlers where we process deferred work after | |
113 | * notification | |
114 | */ | |
115 | struct work_struct control_work; | |
116 | ||
117 | struct list_head ports; | |
118 | ||
119 | /* To protect the list of ports */ | |
120 | spinlock_t ports_lock; | |
121 | ||
122 | /* To protect the vq operations for the control channel */ | |
123 | spinlock_t cvq_lock; | |
124 | ||
125 | /* The current config space is stored here */ | |
b99fa815 | 126 | struct virtio_console_config config; |
17634ba2 AS |
127 | |
128 | /* The virtio device we're associated with */ | |
129 | struct virtio_device *vdev; | |
130 | ||
131 | /* | |
132 | * A couple of virtqueues for the control channel: one for | |
133 | * guest->host transfers, one for host->guest transfers | |
134 | */ | |
135 | struct virtqueue *c_ivq, *c_ovq; | |
136 | ||
137 | /* Array of per-port IO virtqueues */ | |
138 | struct virtqueue **in_vqs, **out_vqs; | |
fb08bd27 AS |
139 | |
140 | /* Used for numbering devices for sysfs and debugfs */ | |
141 | unsigned int drv_index; | |
142 | ||
143 | /* Major number for this device. Ports will be created as minors. */ | |
144 | int chr_major; | |
17634ba2 AS |
145 | }; |
146 | ||
1c85bf35 | 147 | /* This struct holds the per-port data */ |
21206ede | 148 | struct port { |
17634ba2 AS |
149 | /* Next port in the list, head is in the ports_device */ |
150 | struct list_head list; | |
151 | ||
1c85bf35 AS |
152 | /* Pointer to the parent virtio_console device */ |
153 | struct ports_device *portdev; | |
fdb9a054 AS |
154 | |
155 | /* The current buffer from which data has to be fed to readers */ | |
156 | struct port_buffer *inbuf; | |
21206ede | 157 | |
203baab8 AS |
158 | /* |
159 | * To protect the operations on the in_vq associated with this | |
160 | * port. Has to be a spinlock because it can be called from | |
161 | * interrupt context (get_char()). | |
162 | */ | |
163 | spinlock_t inbuf_lock; | |
164 | ||
cdfadfc1 AS |
165 | /* Protect the operations on the out_vq. */ |
166 | spinlock_t outvq_lock; | |
167 | ||
1c85bf35 AS |
168 | /* The IO vqs for this port */ |
169 | struct virtqueue *in_vq, *out_vq; | |
170 | ||
d99393ef AS |
171 | /* File in the debugfs directory that exposes this port's information */ |
172 | struct dentry *debugfs_file; | |
173 | ||
4f23c573 AS |
174 | /* |
175 | * The entries in this struct will be valid if this port is | |
176 | * hooked up to an hvc console | |
177 | */ | |
178 | struct console cons; | |
17634ba2 | 179 | |
fb08bd27 AS |
180 | /* Each port associates with a separate char device */ |
181 | struct cdev cdev; | |
182 | struct device *dev; | |
183 | ||
2030fa49 AS |
184 | /* A waitqueue for poll() or blocking read operations */ |
185 | wait_queue_head_t waitqueue; | |
186 | ||
431edb8a AS |
187 | /* The 'name' of the port that we expose via sysfs properties */ |
188 | char *name; | |
189 | ||
17634ba2 AS |
190 | /* The 'id' to identify the port with the Host */ |
191 | u32 id; | |
2030fa49 | 192 | |
cdfadfc1 AS |
193 | bool outvq_full; |
194 | ||
2030fa49 AS |
195 | /* Is the host device open */ |
196 | bool host_connected; | |
3c7969cc AS |
197 | |
198 | /* We should allow only one process to open a port */ | |
199 | bool guest_connected; | |
21206ede | 200 | }; |
31610434 | 201 | |
971f3390 RR |
202 | /* This is the very early arch-specified put chars function. */ |
203 | static int (*early_put_chars)(u32, const char *, int); | |
204 | ||
38edf58d AS |
205 | static struct port *find_port_by_vtermno(u32 vtermno) |
206 | { | |
207 | struct port *port; | |
4f23c573 | 208 | struct console *cons; |
38edf58d AS |
209 | unsigned long flags; |
210 | ||
211 | spin_lock_irqsave(&pdrvdata_lock, flags); | |
4f23c573 AS |
212 | list_for_each_entry(cons, &pdrvdata.consoles, list) { |
213 | if (cons->vtermno == vtermno) { | |
214 | port = container_of(cons, struct port, cons); | |
38edf58d | 215 | goto out; |
4f23c573 | 216 | } |
38edf58d AS |
217 | } |
218 | port = NULL; | |
219 | out: | |
220 | spin_unlock_irqrestore(&pdrvdata_lock, flags); | |
221 | return port; | |
222 | } | |
223 | ||
17634ba2 AS |
224 | static struct port *find_port_by_id(struct ports_device *portdev, u32 id) |
225 | { | |
226 | struct port *port; | |
227 | unsigned long flags; | |
228 | ||
229 | spin_lock_irqsave(&portdev->ports_lock, flags); | |
230 | list_for_each_entry(port, &portdev->ports, list) | |
231 | if (port->id == id) | |
232 | goto out; | |
233 | port = NULL; | |
234 | out: | |
235 | spin_unlock_irqrestore(&portdev->ports_lock, flags); | |
236 | ||
237 | return port; | |
238 | } | |
239 | ||
203baab8 AS |
240 | static struct port *find_port_by_vq(struct ports_device *portdev, |
241 | struct virtqueue *vq) | |
242 | { | |
243 | struct port *port; | |
203baab8 AS |
244 | unsigned long flags; |
245 | ||
17634ba2 AS |
246 | spin_lock_irqsave(&portdev->ports_lock, flags); |
247 | list_for_each_entry(port, &portdev->ports, list) | |
203baab8 AS |
248 | if (port->in_vq == vq || port->out_vq == vq) |
249 | goto out; | |
203baab8 AS |
250 | port = NULL; |
251 | out: | |
17634ba2 | 252 | spin_unlock_irqrestore(&portdev->ports_lock, flags); |
203baab8 AS |
253 | return port; |
254 | } | |
255 | ||
17634ba2 AS |
256 | static bool is_console_port(struct port *port) |
257 | { | |
258 | if (port->cons.hvc) | |
259 | return true; | |
260 | return false; | |
261 | } | |
262 | ||
263 | static inline bool use_multiport(struct ports_device *portdev) | |
264 | { | |
265 | /* | |
266 | * This condition can be true when put_chars is called from | |
267 | * early_init | |
268 | */ | |
269 | if (!portdev->vdev) | |
270 | return 0; | |
271 | return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT); | |
272 | } | |
273 | ||
fdb9a054 AS |
274 | static void free_buf(struct port_buffer *buf) |
275 | { | |
276 | kfree(buf->buf); | |
277 | kfree(buf); | |
278 | } | |
279 | ||
280 | static struct port_buffer *alloc_buf(size_t buf_size) | |
281 | { | |
282 | struct port_buffer *buf; | |
283 | ||
284 | buf = kmalloc(sizeof(*buf), GFP_KERNEL); | |
285 | if (!buf) | |
286 | goto fail; | |
287 | buf->buf = kzalloc(buf_size, GFP_KERNEL); | |
288 | if (!buf->buf) | |
289 | goto free_buf; | |
290 | buf->len = 0; | |
291 | buf->offset = 0; | |
292 | buf->size = buf_size; | |
293 | return buf; | |
294 | ||
295 | free_buf: | |
296 | kfree(buf); | |
297 | fail: | |
298 | return NULL; | |
299 | } | |
300 | ||
a3cde449 AS |
301 | /* Callers should take appropriate locks */ |
302 | static void *get_inbuf(struct port *port) | |
303 | { | |
304 | struct port_buffer *buf; | |
305 | struct virtqueue *vq; | |
306 | unsigned int len; | |
307 | ||
308 | vq = port->in_vq; | |
505b0451 | 309 | buf = virtqueue_get_buf(vq, &len); |
a3cde449 AS |
310 | if (buf) { |
311 | buf->len = len; | |
312 | buf->offset = 0; | |
313 | } | |
314 | return buf; | |
315 | } | |
316 | ||
e27b5198 AS |
317 | /* |
318 | * Create a scatter-gather list representing our input buffer and put | |
319 | * it in the queue. | |
320 | * | |
321 | * Callers should take appropriate locks. | |
322 | */ | |
203baab8 | 323 | static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf) |
e27b5198 AS |
324 | { |
325 | struct scatterlist sg[1]; | |
203baab8 | 326 | int ret; |
1c85bf35 | 327 | |
e27b5198 AS |
328 | sg_init_one(sg, buf->buf, buf->size); |
329 | ||
505b0451 MT |
330 | ret = virtqueue_add_buf(vq, sg, 0, 1, buf); |
331 | virtqueue_kick(vq); | |
203baab8 AS |
332 | return ret; |
333 | } | |
334 | ||
88f251ac AS |
335 | /* Discard any unread data this port has. Callers lockers. */ |
336 | static void discard_port_data(struct port *port) | |
337 | { | |
338 | struct port_buffer *buf; | |
339 | struct virtqueue *vq; | |
340 | unsigned int len; | |
d6933561 | 341 | int ret; |
88f251ac AS |
342 | |
343 | vq = port->in_vq; | |
344 | if (port->inbuf) | |
345 | buf = port->inbuf; | |
346 | else | |
505b0451 | 347 | buf = virtqueue_get_buf(vq, &len); |
88f251ac | 348 | |
d6933561 AS |
349 | ret = 0; |
350 | while (buf) { | |
351 | if (add_inbuf(vq, buf) < 0) { | |
352 | ret++; | |
353 | free_buf(buf); | |
354 | } | |
505b0451 | 355 | buf = virtqueue_get_buf(vq, &len); |
88f251ac | 356 | } |
88f251ac | 357 | port->inbuf = NULL; |
d6933561 AS |
358 | if (ret) |
359 | dev_warn(port->dev, "Errors adding %d buffers back to vq\n", | |
360 | ret); | |
88f251ac AS |
361 | } |
362 | ||
203baab8 AS |
363 | static bool port_has_data(struct port *port) |
364 | { | |
365 | unsigned long flags; | |
366 | bool ret; | |
367 | ||
203baab8 | 368 | spin_lock_irqsave(&port->inbuf_lock, flags); |
d6933561 | 369 | if (port->inbuf) { |
203baab8 | 370 | ret = true; |
d6933561 AS |
371 | goto out; |
372 | } | |
373 | port->inbuf = get_inbuf(port); | |
374 | if (port->inbuf) { | |
375 | ret = true; | |
376 | goto out; | |
377 | } | |
378 | ret = false; | |
379 | out: | |
203baab8 | 380 | spin_unlock_irqrestore(&port->inbuf_lock, flags); |
203baab8 AS |
381 | return ret; |
382 | } | |
383 | ||
3425e706 AS |
384 | static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id, |
385 | unsigned int event, unsigned int value) | |
17634ba2 AS |
386 | { |
387 | struct scatterlist sg[1]; | |
388 | struct virtio_console_control cpkt; | |
389 | struct virtqueue *vq; | |
604b2ad7 | 390 | unsigned int len; |
17634ba2 | 391 | |
3425e706 | 392 | if (!use_multiport(portdev)) |
17634ba2 AS |
393 | return 0; |
394 | ||
3425e706 | 395 | cpkt.id = port_id; |
17634ba2 AS |
396 | cpkt.event = event; |
397 | cpkt.value = value; | |
398 | ||
3425e706 | 399 | vq = portdev->c_ovq; |
17634ba2 AS |
400 | |
401 | sg_init_one(sg, &cpkt, sizeof(cpkt)); | |
505b0451 MT |
402 | if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt) >= 0) { |
403 | virtqueue_kick(vq); | |
404 | while (!virtqueue_get_buf(vq, &len)) | |
17634ba2 AS |
405 | cpu_relax(); |
406 | } | |
407 | return 0; | |
408 | } | |
409 | ||
3425e706 AS |
410 | static ssize_t send_control_msg(struct port *port, unsigned int event, |
411 | unsigned int value) | |
412 | { | |
413 | return __send_control_msg(port->portdev, port->id, event, value); | |
414 | } | |
415 | ||
cdfadfc1 AS |
416 | /* Callers must take the port->outvq_lock */ |
417 | static void reclaim_consumed_buffers(struct port *port) | |
418 | { | |
419 | void *buf; | |
420 | unsigned int len; | |
421 | ||
422 | while ((buf = virtqueue_get_buf(port->out_vq, &len))) { | |
423 | kfree(buf); | |
424 | port->outvq_full = false; | |
425 | } | |
426 | } | |
427 | ||
428 | static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count, | |
429 | bool nonblock) | |
f997f00b AS |
430 | { |
431 | struct scatterlist sg[1]; | |
432 | struct virtqueue *out_vq; | |
433 | ssize_t ret; | |
cdfadfc1 | 434 | unsigned long flags; |
f997f00b AS |
435 | unsigned int len; |
436 | ||
437 | out_vq = port->out_vq; | |
438 | ||
cdfadfc1 AS |
439 | spin_lock_irqsave(&port->outvq_lock, flags); |
440 | ||
441 | reclaim_consumed_buffers(port); | |
442 | ||
f997f00b | 443 | sg_init_one(sg, in_buf, in_count); |
505b0451 | 444 | ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf); |
f997f00b AS |
445 | |
446 | /* Tell Host to go! */ | |
505b0451 | 447 | virtqueue_kick(out_vq); |
f997f00b AS |
448 | |
449 | if (ret < 0) { | |
9ff4cfab | 450 | in_count = 0; |
cdfadfc1 | 451 | goto done; |
f997f00b AS |
452 | } |
453 | ||
cdfadfc1 AS |
454 | if (ret == 0) |
455 | port->outvq_full = true; | |
456 | ||
457 | if (nonblock) | |
458 | goto done; | |
459 | ||
460 | /* | |
461 | * Wait till the host acknowledges it pushed out the data we | |
531295e6 AS |
462 | * sent. This is done for data from the hvc_console; the tty |
463 | * operations are performed with spinlocks held so we can't | |
464 | * sleep here. An alternative would be to copy the data to a | |
465 | * buffer and relax the spinning requirement. The downside is | |
466 | * we need to kmalloc a GFP_ATOMIC buffer each time the | |
467 | * console driver writes something out. | |
cdfadfc1 | 468 | */ |
505b0451 | 469 | while (!virtqueue_get_buf(out_vq, &len)) |
f997f00b | 470 | cpu_relax(); |
cdfadfc1 AS |
471 | done: |
472 | spin_unlock_irqrestore(&port->outvq_lock, flags); | |
473 | /* | |
474 | * We're expected to return the amount of data we wrote -- all | |
475 | * of it | |
476 | */ | |
9ff4cfab | 477 | return in_count; |
f997f00b AS |
478 | } |
479 | ||
203baab8 AS |
480 | /* |
481 | * Give out the data that's requested from the buffer that we have | |
482 | * queued up. | |
483 | */ | |
b766ceed AS |
484 | static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count, |
485 | bool to_user) | |
203baab8 AS |
486 | { |
487 | struct port_buffer *buf; | |
488 | unsigned long flags; | |
489 | ||
490 | if (!out_count || !port_has_data(port)) | |
491 | return 0; | |
492 | ||
493 | buf = port->inbuf; | |
b766ceed | 494 | out_count = min(out_count, buf->len - buf->offset); |
203baab8 | 495 | |
b766ceed AS |
496 | if (to_user) { |
497 | ssize_t ret; | |
498 | ||
499 | ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count); | |
500 | if (ret) | |
501 | return -EFAULT; | |
502 | } else { | |
503 | memcpy(out_buf, buf->buf + buf->offset, out_count); | |
504 | } | |
203baab8 | 505 | |
203baab8 AS |
506 | buf->offset += out_count; |
507 | ||
508 | if (buf->offset == buf->len) { | |
509 | /* | |
510 | * We're done using all the data in this buffer. | |
511 | * Re-queue so that the Host can send us more data. | |
512 | */ | |
513 | spin_lock_irqsave(&port->inbuf_lock, flags); | |
514 | port->inbuf = NULL; | |
515 | ||
516 | if (add_inbuf(port->in_vq, buf) < 0) | |
fb08bd27 | 517 | dev_warn(port->dev, "failed add_buf\n"); |
203baab8 AS |
518 | |
519 | spin_unlock_irqrestore(&port->inbuf_lock, flags); | |
520 | } | |
b766ceed | 521 | /* Return the number of bytes actually copied */ |
203baab8 | 522 | return out_count; |
e27b5198 AS |
523 | } |
524 | ||
2030fa49 | 525 | /* The condition that must be true for polling to end */ |
60caacd3 | 526 | static bool will_read_block(struct port *port) |
2030fa49 | 527 | { |
60caacd3 | 528 | return !port_has_data(port) && port->host_connected; |
2030fa49 AS |
529 | } |
530 | ||
cdfadfc1 AS |
531 | static bool will_write_block(struct port *port) |
532 | { | |
533 | bool ret; | |
534 | ||
60e5e0b8 AS |
535 | if (!port->guest_connected) { |
536 | /* Port got hot-unplugged. Let's exit. */ | |
537 | return false; | |
538 | } | |
cdfadfc1 AS |
539 | if (!port->host_connected) |
540 | return true; | |
541 | ||
542 | spin_lock_irq(&port->outvq_lock); | |
543 | /* | |
544 | * Check if the Host has consumed any buffers since we last | |
545 | * sent data (this is only applicable for nonblocking ports). | |
546 | */ | |
547 | reclaim_consumed_buffers(port); | |
548 | ret = port->outvq_full; | |
549 | spin_unlock_irq(&port->outvq_lock); | |
550 | ||
551 | return ret; | |
552 | } | |
553 | ||
2030fa49 AS |
554 | static ssize_t port_fops_read(struct file *filp, char __user *ubuf, |
555 | size_t count, loff_t *offp) | |
556 | { | |
557 | struct port *port; | |
558 | ssize_t ret; | |
559 | ||
560 | port = filp->private_data; | |
561 | ||
562 | if (!port_has_data(port)) { | |
563 | /* | |
564 | * If nothing's connected on the host just return 0 in | |
565 | * case of list_empty; this tells the userspace app | |
566 | * that there's no connection | |
567 | */ | |
568 | if (!port->host_connected) | |
569 | return 0; | |
570 | if (filp->f_flags & O_NONBLOCK) | |
571 | return -EAGAIN; | |
572 | ||
573 | ret = wait_event_interruptible(port->waitqueue, | |
60caacd3 | 574 | !will_read_block(port)); |
2030fa49 AS |
575 | if (ret < 0) |
576 | return ret; | |
577 | } | |
578 | /* | |
579 | * We could've received a disconnection message while we were | |
580 | * waiting for more data. | |
581 | * | |
582 | * This check is not clubbed in the if() statement above as we | |
583 | * might receive some data as well as the host could get | |
584 | * disconnected after we got woken up from our wait. So we | |
585 | * really want to give off whatever data we have and only then | |
586 | * check for host_connected. | |
587 | */ | |
588 | if (!port_has_data(port) && !port->host_connected) | |
589 | return 0; | |
590 | ||
591 | return fill_readbuf(port, ubuf, count, true); | |
592 | } | |
593 | ||
594 | static ssize_t port_fops_write(struct file *filp, const char __user *ubuf, | |
595 | size_t count, loff_t *offp) | |
596 | { | |
597 | struct port *port; | |
598 | char *buf; | |
599 | ssize_t ret; | |
cdfadfc1 | 600 | bool nonblock; |
2030fa49 | 601 | |
65745422 AS |
602 | /* Userspace could be out to fool us */ |
603 | if (!count) | |
604 | return 0; | |
605 | ||
2030fa49 AS |
606 | port = filp->private_data; |
607 | ||
cdfadfc1 AS |
608 | nonblock = filp->f_flags & O_NONBLOCK; |
609 | ||
610 | if (will_write_block(port)) { | |
611 | if (nonblock) | |
612 | return -EAGAIN; | |
613 | ||
614 | ret = wait_event_interruptible(port->waitqueue, | |
615 | !will_write_block(port)); | |
616 | if (ret < 0) | |
617 | return ret; | |
618 | } | |
619 | ||
2030fa49 AS |
620 | count = min((size_t)(32 * 1024), count); |
621 | ||
622 | buf = kmalloc(count, GFP_KERNEL); | |
623 | if (!buf) | |
624 | return -ENOMEM; | |
625 | ||
626 | ret = copy_from_user(buf, ubuf, count); | |
627 | if (ret) { | |
628 | ret = -EFAULT; | |
629 | goto free_buf; | |
630 | } | |
631 | ||
531295e6 AS |
632 | /* |
633 | * We now ask send_buf() to not spin for generic ports -- we | |
634 | * can re-use the same code path that non-blocking file | |
635 | * descriptors take for blocking file descriptors since the | |
636 | * wait is already done and we're certain the write will go | |
637 | * through to the host. | |
638 | */ | |
639 | nonblock = true; | |
cdfadfc1 AS |
640 | ret = send_buf(port, buf, count, nonblock); |
641 | ||
642 | if (nonblock && ret > 0) | |
643 | goto out; | |
644 | ||
2030fa49 AS |
645 | free_buf: |
646 | kfree(buf); | |
cdfadfc1 | 647 | out: |
2030fa49 AS |
648 | return ret; |
649 | } | |
650 | ||
651 | static unsigned int port_fops_poll(struct file *filp, poll_table *wait) | |
652 | { | |
653 | struct port *port; | |
654 | unsigned int ret; | |
655 | ||
656 | port = filp->private_data; | |
657 | poll_wait(filp, &port->waitqueue, wait); | |
658 | ||
659 | ret = 0; | |
6df7aadc | 660 | if (!will_read_block(port)) |
2030fa49 | 661 | ret |= POLLIN | POLLRDNORM; |
cdfadfc1 | 662 | if (!will_write_block(port)) |
2030fa49 AS |
663 | ret |= POLLOUT; |
664 | if (!port->host_connected) | |
665 | ret |= POLLHUP; | |
666 | ||
667 | return ret; | |
668 | } | |
669 | ||
670 | static int port_fops_release(struct inode *inode, struct file *filp) | |
671 | { | |
672 | struct port *port; | |
673 | ||
674 | port = filp->private_data; | |
675 | ||
676 | /* Notify host of port being closed */ | |
677 | send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0); | |
678 | ||
88f251ac | 679 | spin_lock_irq(&port->inbuf_lock); |
3c7969cc AS |
680 | port->guest_connected = false; |
681 | ||
88f251ac AS |
682 | discard_port_data(port); |
683 | ||
684 | spin_unlock_irq(&port->inbuf_lock); | |
685 | ||
cdfadfc1 AS |
686 | spin_lock_irq(&port->outvq_lock); |
687 | reclaim_consumed_buffers(port); | |
688 | spin_unlock_irq(&port->outvq_lock); | |
689 | ||
2030fa49 AS |
690 | return 0; |
691 | } | |
692 | ||
693 | static int port_fops_open(struct inode *inode, struct file *filp) | |
694 | { | |
695 | struct cdev *cdev = inode->i_cdev; | |
696 | struct port *port; | |
697 | ||
698 | port = container_of(cdev, struct port, cdev); | |
699 | filp->private_data = port; | |
700 | ||
701 | /* | |
702 | * Don't allow opening of console port devices -- that's done | |
703 | * via /dev/hvc | |
704 | */ | |
705 | if (is_console_port(port)) | |
706 | return -ENXIO; | |
707 | ||
3c7969cc AS |
708 | /* Allow only one process to open a particular port at a time */ |
709 | spin_lock_irq(&port->inbuf_lock); | |
710 | if (port->guest_connected) { | |
711 | spin_unlock_irq(&port->inbuf_lock); | |
712 | return -EMFILE; | |
713 | } | |
714 | ||
715 | port->guest_connected = true; | |
716 | spin_unlock_irq(&port->inbuf_lock); | |
717 | ||
cdfadfc1 AS |
718 | spin_lock_irq(&port->outvq_lock); |
719 | /* | |
720 | * There might be a chance that we missed reclaiming a few | |
721 | * buffers in the window of the port getting previously closed | |
722 | * and opening now. | |
723 | */ | |
724 | reclaim_consumed_buffers(port); | |
725 | spin_unlock_irq(&port->outvq_lock); | |
726 | ||
2030fa49 AS |
727 | /* Notify host of port being opened */ |
728 | send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1); | |
729 | ||
730 | return 0; | |
731 | } | |
732 | ||
733 | /* | |
734 | * The file operations that we support: programs in the guest can open | |
735 | * a console device, read from it, write to it, poll for data and | |
736 | * close it. The devices are at | |
737 | * /dev/vport<device number>p<port number> | |
738 | */ | |
739 | static const struct file_operations port_fops = { | |
740 | .owner = THIS_MODULE, | |
741 | .open = port_fops_open, | |
742 | .read = port_fops_read, | |
743 | .write = port_fops_write, | |
744 | .poll = port_fops_poll, | |
745 | .release = port_fops_release, | |
746 | }; | |
747 | ||
a23ea924 RR |
748 | /* |
749 | * The put_chars() callback is pretty straightforward. | |
31610434 | 750 | * |
a23ea924 RR |
751 | * We turn the characters into a scatter-gather list, add it to the |
752 | * output queue and then kick the Host. Then we sit here waiting for | |
753 | * it to finish: inefficient in theory, but in practice | |
754 | * implementations will do it immediately (lguest's Launcher does). | |
755 | */ | |
31610434 RR |
756 | static int put_chars(u32 vtermno, const char *buf, int count) |
757 | { | |
21206ede | 758 | struct port *port; |
38edf58d | 759 | |
162a689a FD |
760 | if (unlikely(early_put_chars)) |
761 | return early_put_chars(vtermno, buf, count); | |
762 | ||
38edf58d AS |
763 | port = find_port_by_vtermno(vtermno); |
764 | if (!port) | |
6dc69f97 | 765 | return -EPIPE; |
31610434 | 766 | |
cdfadfc1 | 767 | return send_buf(port, (void *)buf, count, false); |
31610434 RR |
768 | } |
769 | ||
a23ea924 RR |
770 | /* |
771 | * get_chars() is the callback from the hvc_console infrastructure | |
772 | * when an interrupt is received. | |
31610434 | 773 | * |
203baab8 AS |
774 | * We call out to fill_readbuf that gets us the required data from the |
775 | * buffers that are queued up. | |
a23ea924 | 776 | */ |
31610434 RR |
777 | static int get_chars(u32 vtermno, char *buf, int count) |
778 | { | |
21206ede RR |
779 | struct port *port; |
780 | ||
6dc69f97 AS |
781 | /* If we've not set up the port yet, we have no input to give. */ |
782 | if (unlikely(early_put_chars)) | |
783 | return 0; | |
784 | ||
38edf58d AS |
785 | port = find_port_by_vtermno(vtermno); |
786 | if (!port) | |
6dc69f97 | 787 | return -EPIPE; |
21206ede | 788 | |
31610434 | 789 | /* If we don't have an input queue yet, we can't get input. */ |
21206ede | 790 | BUG_ON(!port->in_vq); |
31610434 | 791 | |
b766ceed | 792 | return fill_readbuf(port, buf, count, false); |
31610434 | 793 | } |
31610434 | 794 | |
cb06e367 | 795 | static void resize_console(struct port *port) |
c2983458 | 796 | { |
cb06e367 | 797 | struct virtio_device *vdev; |
c2983458 | 798 | |
2de16a49 | 799 | /* The port could have been hot-unplugged */ |
9778829c | 800 | if (!port || !is_console_port(port)) |
2de16a49 AS |
801 | return; |
802 | ||
cb06e367 | 803 | vdev = port->portdev->vdev; |
9778829c AS |
804 | if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE)) |
805 | hvc_resize(port->cons.hvc, port->cons.ws); | |
c2983458 CB |
806 | } |
807 | ||
38edf58d | 808 | /* We set the configuration at this point, since we now have a tty */ |
91fcad19 CB |
809 | static int notifier_add_vio(struct hvc_struct *hp, int data) |
810 | { | |
38edf58d AS |
811 | struct port *port; |
812 | ||
813 | port = find_port_by_vtermno(hp->vtermno); | |
814 | if (!port) | |
815 | return -EINVAL; | |
816 | ||
91fcad19 | 817 | hp->irq_requested = 1; |
cb06e367 | 818 | resize_console(port); |
c2983458 | 819 | |
91fcad19 CB |
820 | return 0; |
821 | } | |
822 | ||
823 | static void notifier_del_vio(struct hvc_struct *hp, int data) | |
824 | { | |
825 | hp->irq_requested = 0; | |
826 | } | |
827 | ||
17634ba2 | 828 | /* The operations for console ports. */ |
1dff3996 | 829 | static const struct hv_ops hv_ops = { |
971f3390 RR |
830 | .get_chars = get_chars, |
831 | .put_chars = put_chars, | |
832 | .notifier_add = notifier_add_vio, | |
833 | .notifier_del = notifier_del_vio, | |
834 | .notifier_hangup = notifier_del_vio, | |
835 | }; | |
836 | ||
837 | /* | |
838 | * Console drivers are initialized very early so boot messages can go | |
839 | * out, so we do things slightly differently from the generic virtio | |
840 | * initialization of the net and block drivers. | |
841 | * | |
842 | * At this stage, the console is output-only. It's too early to set | |
843 | * up a virtqueue, so we let the drivers do some boutique early-output | |
844 | * thing. | |
845 | */ | |
846 | int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int)) | |
847 | { | |
848 | early_put_chars = put_chars; | |
849 | return hvc_instantiate(0, 0, &hv_ops); | |
850 | } | |
851 | ||
17634ba2 | 852 | int init_port_console(struct port *port) |
cfa6d379 AS |
853 | { |
854 | int ret; | |
855 | ||
856 | /* | |
857 | * The Host's telling us this port is a console port. Hook it | |
858 | * up with an hvc console. | |
859 | * | |
860 | * To set up and manage our virtual console, we call | |
861 | * hvc_alloc(). | |
862 | * | |
863 | * The first argument of hvc_alloc() is the virtual console | |
864 | * number. The second argument is the parameter for the | |
865 | * notification mechanism (like irq number). We currently | |
866 | * leave this as zero, virtqueues have implicit notifications. | |
867 | * | |
868 | * The third argument is a "struct hv_ops" containing the | |
869 | * put_chars() get_chars(), notifier_add() and notifier_del() | |
870 | * pointers. The final argument is the output buffer size: we | |
871 | * can do any size, so we put PAGE_SIZE here. | |
872 | */ | |
873 | port->cons.vtermno = pdrvdata.next_vtermno; | |
874 | ||
875 | port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE); | |
876 | if (IS_ERR(port->cons.hvc)) { | |
877 | ret = PTR_ERR(port->cons.hvc); | |
298add72 AS |
878 | dev_err(port->dev, |
879 | "error %d allocating hvc for port\n", ret); | |
cfa6d379 AS |
880 | port->cons.hvc = NULL; |
881 | return ret; | |
882 | } | |
883 | spin_lock_irq(&pdrvdata_lock); | |
884 | pdrvdata.next_vtermno++; | |
885 | list_add_tail(&port->cons.list, &pdrvdata.consoles); | |
886 | spin_unlock_irq(&pdrvdata_lock); | |
3c7969cc | 887 | port->guest_connected = true; |
cfa6d379 | 888 | |
1d05160b AS |
889 | /* |
890 | * Start using the new console output if this is the first | |
891 | * console to come up. | |
892 | */ | |
893 | if (early_put_chars) | |
894 | early_put_chars = NULL; | |
895 | ||
2030fa49 AS |
896 | /* Notify host of port being opened */ |
897 | send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1); | |
898 | ||
cfa6d379 AS |
899 | return 0; |
900 | } | |
901 | ||
431edb8a AS |
902 | static ssize_t show_port_name(struct device *dev, |
903 | struct device_attribute *attr, char *buffer) | |
904 | { | |
905 | struct port *port; | |
906 | ||
907 | port = dev_get_drvdata(dev); | |
908 | ||
909 | return sprintf(buffer, "%s\n", port->name); | |
910 | } | |
911 | ||
912 | static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL); | |
913 | ||
914 | static struct attribute *port_sysfs_entries[] = { | |
915 | &dev_attr_name.attr, | |
916 | NULL | |
917 | }; | |
918 | ||
919 | static struct attribute_group port_attribute_group = { | |
920 | .name = NULL, /* put in device directory */ | |
921 | .attrs = port_sysfs_entries, | |
922 | }; | |
923 | ||
d99393ef AS |
924 | static int debugfs_open(struct inode *inode, struct file *filp) |
925 | { | |
926 | filp->private_data = inode->i_private; | |
927 | return 0; | |
928 | } | |
929 | ||
930 | static ssize_t debugfs_read(struct file *filp, char __user *ubuf, | |
931 | size_t count, loff_t *offp) | |
932 | { | |
933 | struct port *port; | |
934 | char *buf; | |
935 | ssize_t ret, out_offset, out_count; | |
936 | ||
937 | out_count = 1024; | |
938 | buf = kmalloc(out_count, GFP_KERNEL); | |
939 | if (!buf) | |
940 | return -ENOMEM; | |
941 | ||
942 | port = filp->private_data; | |
943 | out_offset = 0; | |
944 | out_offset += snprintf(buf + out_offset, out_count, | |
945 | "name: %s\n", port->name ? port->name : ""); | |
946 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
947 | "guest_connected: %d\n", port->guest_connected); | |
948 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
949 | "host_connected: %d\n", port->host_connected); | |
cdfadfc1 AS |
950 | out_offset += snprintf(buf + out_offset, out_count - out_offset, |
951 | "outvq_full: %d\n", port->outvq_full); | |
d99393ef AS |
952 | out_offset += snprintf(buf + out_offset, out_count - out_offset, |
953 | "is_console: %s\n", | |
954 | is_console_port(port) ? "yes" : "no"); | |
955 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
956 | "console_vtermno: %u\n", port->cons.vtermno); | |
957 | ||
958 | ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); | |
959 | kfree(buf); | |
960 | return ret; | |
961 | } | |
962 | ||
963 | static const struct file_operations port_debugfs_ops = { | |
964 | .owner = THIS_MODULE, | |
965 | .open = debugfs_open, | |
966 | .read = debugfs_read, | |
967 | }; | |
968 | ||
9778829c AS |
969 | static void set_console_size(struct port *port, u16 rows, u16 cols) |
970 | { | |
971 | if (!port || !is_console_port(port)) | |
972 | return; | |
973 | ||
974 | port->cons.ws.ws_row = rows; | |
975 | port->cons.ws.ws_col = cols; | |
976 | } | |
977 | ||
c446f8fc AS |
978 | static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock) |
979 | { | |
980 | struct port_buffer *buf; | |
981 | unsigned int nr_added_bufs; | |
982 | int ret; | |
983 | ||
984 | nr_added_bufs = 0; | |
985 | do { | |
986 | buf = alloc_buf(PAGE_SIZE); | |
987 | if (!buf) | |
988 | break; | |
989 | ||
990 | spin_lock_irq(lock); | |
991 | ret = add_inbuf(vq, buf); | |
992 | if (ret < 0) { | |
993 | spin_unlock_irq(lock); | |
994 | free_buf(buf); | |
995 | break; | |
996 | } | |
997 | nr_added_bufs++; | |
998 | spin_unlock_irq(lock); | |
999 | } while (ret > 0); | |
1000 | ||
1001 | return nr_added_bufs; | |
1002 | } | |
1003 | ||
1004 | static int add_port(struct ports_device *portdev, u32 id) | |
1005 | { | |
1006 | char debugfs_name[16]; | |
1007 | struct port *port; | |
1008 | struct port_buffer *buf; | |
1009 | dev_t devt; | |
1010 | unsigned int nr_added_bufs; | |
1011 | int err; | |
1012 | ||
1013 | port = kmalloc(sizeof(*port), GFP_KERNEL); | |
1014 | if (!port) { | |
1015 | err = -ENOMEM; | |
1016 | goto fail; | |
1017 | } | |
1018 | ||
1019 | port->portdev = portdev; | |
1020 | port->id = id; | |
1021 | ||
1022 | port->name = NULL; | |
1023 | port->inbuf = NULL; | |
1024 | port->cons.hvc = NULL; | |
1025 | ||
9778829c AS |
1026 | port->cons.ws.ws_row = port->cons.ws.ws_col = 0; |
1027 | ||
c446f8fc AS |
1028 | port->host_connected = port->guest_connected = false; |
1029 | ||
cdfadfc1 AS |
1030 | port->outvq_full = false; |
1031 | ||
c446f8fc AS |
1032 | port->in_vq = portdev->in_vqs[port->id]; |
1033 | port->out_vq = portdev->out_vqs[port->id]; | |
1034 | ||
1035 | cdev_init(&port->cdev, &port_fops); | |
1036 | ||
1037 | devt = MKDEV(portdev->chr_major, id); | |
1038 | err = cdev_add(&port->cdev, devt, 1); | |
1039 | if (err < 0) { | |
1040 | dev_err(&port->portdev->vdev->dev, | |
1041 | "Error %d adding cdev for port %u\n", err, id); | |
1042 | goto free_port; | |
1043 | } | |
1044 | port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev, | |
1045 | devt, port, "vport%up%u", | |
1046 | port->portdev->drv_index, id); | |
1047 | if (IS_ERR(port->dev)) { | |
1048 | err = PTR_ERR(port->dev); | |
1049 | dev_err(&port->portdev->vdev->dev, | |
1050 | "Error %d creating device for port %u\n", | |
1051 | err, id); | |
1052 | goto free_cdev; | |
1053 | } | |
1054 | ||
1055 | spin_lock_init(&port->inbuf_lock); | |
cdfadfc1 | 1056 | spin_lock_init(&port->outvq_lock); |
c446f8fc AS |
1057 | init_waitqueue_head(&port->waitqueue); |
1058 | ||
1059 | /* Fill the in_vq with buffers so the host can send us data. */ | |
1060 | nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock); | |
1061 | if (!nr_added_bufs) { | |
1062 | dev_err(port->dev, "Error allocating inbufs\n"); | |
1063 | err = -ENOMEM; | |
1064 | goto free_device; | |
1065 | } | |
1066 | ||
1067 | /* | |
1068 | * If we're not using multiport support, this has to be a console port | |
1069 | */ | |
1070 | if (!use_multiport(port->portdev)) { | |
1071 | err = init_port_console(port); | |
1072 | if (err) | |
1073 | goto free_inbufs; | |
1074 | } | |
1075 | ||
1076 | spin_lock_irq(&portdev->ports_lock); | |
1077 | list_add_tail(&port->list, &port->portdev->ports); | |
1078 | spin_unlock_irq(&portdev->ports_lock); | |
1079 | ||
1080 | /* | |
1081 | * Tell the Host we're set so that it can send us various | |
1082 | * configuration parameters for this port (eg, port name, | |
1083 | * caching, whether this is a console port, etc.) | |
1084 | */ | |
1085 | send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1); | |
1086 | ||
1087 | if (pdrvdata.debugfs_dir) { | |
1088 | /* | |
1089 | * Finally, create the debugfs file that we can use to | |
1090 | * inspect a port's state at any time | |
1091 | */ | |
1092 | sprintf(debugfs_name, "vport%up%u", | |
1093 | port->portdev->drv_index, id); | |
1094 | port->debugfs_file = debugfs_create_file(debugfs_name, 0444, | |
1095 | pdrvdata.debugfs_dir, | |
1096 | port, | |
1097 | &port_debugfs_ops); | |
1098 | } | |
1099 | return 0; | |
1100 | ||
1101 | free_inbufs: | |
1102 | while ((buf = virtqueue_detach_unused_buf(port->in_vq))) | |
1103 | free_buf(buf); | |
1104 | free_device: | |
1105 | device_destroy(pdrvdata.class, port->dev->devt); | |
1106 | free_cdev: | |
1107 | cdev_del(&port->cdev); | |
1108 | free_port: | |
1109 | kfree(port); | |
1110 | fail: | |
1111 | /* The host might want to notify management sw about port add failure */ | |
0643e4c6 | 1112 | __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0); |
c446f8fc AS |
1113 | return err; |
1114 | } | |
1115 | ||
1f7aa42d AS |
1116 | /* Remove all port-specific data. */ |
1117 | static int remove_port(struct port *port) | |
1118 | { | |
a9cdd485 AS |
1119 | struct port_buffer *buf; |
1120 | ||
0047634d AS |
1121 | if (port->guest_connected) { |
1122 | port->guest_connected = false; | |
1123 | port->host_connected = false; | |
1124 | wake_up_interruptible(&port->waitqueue); | |
1125 | send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0); | |
1126 | } | |
1127 | ||
1f7aa42d AS |
1128 | spin_lock_irq(&port->portdev->ports_lock); |
1129 | list_del(&port->list); | |
1130 | spin_unlock_irq(&port->portdev->ports_lock); | |
1131 | ||
1132 | if (is_console_port(port)) { | |
1133 | spin_lock_irq(&pdrvdata_lock); | |
1134 | list_del(&port->cons.list); | |
1135 | spin_unlock_irq(&pdrvdata_lock); | |
69eb9a9f AS |
1136 | #if 0 |
1137 | /* | |
1138 | * hvc_remove() not called as removing one hvc port | |
1139 | * results in other hvc ports getting frozen. | |
1140 | * | |
1141 | * Once this is resolved in hvc, this functionality | |
1142 | * will be enabled. Till that is done, the -EPIPE | |
1143 | * return from get_chars() above will help | |
1144 | * hvc_console.c to clean up on ports we remove here. | |
1145 | */ | |
1f7aa42d | 1146 | hvc_remove(port->cons.hvc); |
69eb9a9f | 1147 | #endif |
1f7aa42d | 1148 | } |
1f7aa42d AS |
1149 | sysfs_remove_group(&port->dev->kobj, &port_attribute_group); |
1150 | device_destroy(pdrvdata.class, port->dev->devt); | |
1151 | cdev_del(&port->cdev); | |
1152 | ||
a9cdd485 | 1153 | /* Remove unused data this port might have received. */ |
1f7aa42d | 1154 | discard_port_data(port); |
a9cdd485 | 1155 | |
cdfadfc1 AS |
1156 | reclaim_consumed_buffers(port); |
1157 | ||
a9cdd485 | 1158 | /* Remove buffers we queued up for the Host to send us data in. */ |
505b0451 | 1159 | while ((buf = virtqueue_detach_unused_buf(port->in_vq))) |
a9cdd485 AS |
1160 | free_buf(buf); |
1161 | ||
1f7aa42d AS |
1162 | kfree(port->name); |
1163 | ||
d99393ef AS |
1164 | debugfs_remove(port->debugfs_file); |
1165 | ||
1f7aa42d AS |
1166 | kfree(port); |
1167 | return 0; | |
1168 | } | |
1169 | ||
17634ba2 AS |
1170 | /* Any private messages that the Host and Guest want to share */ |
1171 | static void handle_control_message(struct ports_device *portdev, | |
1172 | struct port_buffer *buf) | |
1173 | { | |
1174 | struct virtio_console_control *cpkt; | |
1175 | struct port *port; | |
431edb8a AS |
1176 | size_t name_size; |
1177 | int err; | |
17634ba2 AS |
1178 | |
1179 | cpkt = (struct virtio_console_control *)(buf->buf + buf->offset); | |
1180 | ||
1181 | port = find_port_by_id(portdev, cpkt->id); | |
f909f850 | 1182 | if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) { |
17634ba2 AS |
1183 | /* No valid header at start of buffer. Drop it. */ |
1184 | dev_dbg(&portdev->vdev->dev, | |
1185 | "Invalid index %u in control packet\n", cpkt->id); | |
1186 | return; | |
1187 | } | |
1188 | ||
1189 | switch (cpkt->event) { | |
f909f850 AS |
1190 | case VIRTIO_CONSOLE_PORT_ADD: |
1191 | if (port) { | |
1d05160b AS |
1192 | dev_dbg(&portdev->vdev->dev, |
1193 | "Port %u already added\n", port->id); | |
f909f850 AS |
1194 | send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1); |
1195 | break; | |
1196 | } | |
1197 | if (cpkt->id >= portdev->config.max_nr_ports) { | |
1198 | dev_warn(&portdev->vdev->dev, | |
1199 | "Request for adding port with out-of-bound id %u, max. supported id: %u\n", | |
1200 | cpkt->id, portdev->config.max_nr_ports - 1); | |
1201 | break; | |
1202 | } | |
1203 | add_port(portdev, cpkt->id); | |
1204 | break; | |
1205 | case VIRTIO_CONSOLE_PORT_REMOVE: | |
1206 | remove_port(port); | |
1207 | break; | |
17634ba2 AS |
1208 | case VIRTIO_CONSOLE_CONSOLE_PORT: |
1209 | if (!cpkt->value) | |
1210 | break; | |
1211 | if (is_console_port(port)) | |
1212 | break; | |
1213 | ||
1214 | init_port_console(port); | |
1215 | /* | |
1216 | * Could remove the port here in case init fails - but | |
1217 | * have to notify the host first. | |
1218 | */ | |
1219 | break; | |
8345adbf AS |
1220 | case VIRTIO_CONSOLE_RESIZE: { |
1221 | struct { | |
1222 | __u16 rows; | |
1223 | __u16 cols; | |
1224 | } size; | |
1225 | ||
17634ba2 AS |
1226 | if (!is_console_port(port)) |
1227 | break; | |
8345adbf AS |
1228 | |
1229 | memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt), | |
1230 | sizeof(size)); | |
1231 | set_console_size(port, size.rows, size.cols); | |
1232 | ||
17634ba2 AS |
1233 | port->cons.hvc->irq_requested = 1; |
1234 | resize_console(port); | |
1235 | break; | |
8345adbf | 1236 | } |
2030fa49 AS |
1237 | case VIRTIO_CONSOLE_PORT_OPEN: |
1238 | port->host_connected = cpkt->value; | |
1239 | wake_up_interruptible(&port->waitqueue); | |
cdfadfc1 AS |
1240 | /* |
1241 | * If the host port got closed and the host had any | |
1242 | * unconsumed buffers, we'll be able to reclaim them | |
1243 | * now. | |
1244 | */ | |
1245 | spin_lock_irq(&port->outvq_lock); | |
1246 | reclaim_consumed_buffers(port); | |
1247 | spin_unlock_irq(&port->outvq_lock); | |
2030fa49 | 1248 | break; |
431edb8a AS |
1249 | case VIRTIO_CONSOLE_PORT_NAME: |
1250 | /* | |
1251 | * Skip the size of the header and the cpkt to get the size | |
1252 | * of the name that was sent | |
1253 | */ | |
1254 | name_size = buf->len - buf->offset - sizeof(*cpkt) + 1; | |
1255 | ||
1256 | port->name = kmalloc(name_size, GFP_KERNEL); | |
1257 | if (!port->name) { | |
1258 | dev_err(port->dev, | |
1259 | "Not enough space to store port name\n"); | |
1260 | break; | |
1261 | } | |
1262 | strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt), | |
1263 | name_size - 1); | |
1264 | port->name[name_size - 1] = 0; | |
1265 | ||
1266 | /* | |
1267 | * Since we only have one sysfs attribute, 'name', | |
1268 | * create it only if we have a name for the port. | |
1269 | */ | |
1270 | err = sysfs_create_group(&port->dev->kobj, | |
1271 | &port_attribute_group); | |
ec64213c | 1272 | if (err) { |
431edb8a AS |
1273 | dev_err(port->dev, |
1274 | "Error %d creating sysfs device attributes\n", | |
1275 | err); | |
ec64213c AS |
1276 | } else { |
1277 | /* | |
1278 | * Generate a udev event so that appropriate | |
1279 | * symlinks can be created based on udev | |
1280 | * rules. | |
1281 | */ | |
1282 | kobject_uevent(&port->dev->kobj, KOBJ_CHANGE); | |
1283 | } | |
431edb8a | 1284 | break; |
17634ba2 AS |
1285 | } |
1286 | } | |
1287 | ||
1288 | static void control_work_handler(struct work_struct *work) | |
1289 | { | |
1290 | struct ports_device *portdev; | |
1291 | struct virtqueue *vq; | |
1292 | struct port_buffer *buf; | |
1293 | unsigned int len; | |
1294 | ||
1295 | portdev = container_of(work, struct ports_device, control_work); | |
1296 | vq = portdev->c_ivq; | |
1297 | ||
1298 | spin_lock(&portdev->cvq_lock); | |
505b0451 | 1299 | while ((buf = virtqueue_get_buf(vq, &len))) { |
17634ba2 AS |
1300 | spin_unlock(&portdev->cvq_lock); |
1301 | ||
1302 | buf->len = len; | |
1303 | buf->offset = 0; | |
1304 | ||
1305 | handle_control_message(portdev, buf); | |
1306 | ||
1307 | spin_lock(&portdev->cvq_lock); | |
1308 | if (add_inbuf(portdev->c_ivq, buf) < 0) { | |
1309 | dev_warn(&portdev->vdev->dev, | |
1310 | "Error adding buffer to queue\n"); | |
1311 | free_buf(buf); | |
1312 | } | |
1313 | } | |
1314 | spin_unlock(&portdev->cvq_lock); | |
1315 | } | |
1316 | ||
1317 | static void in_intr(struct virtqueue *vq) | |
1318 | { | |
1319 | struct port *port; | |
1320 | unsigned long flags; | |
1321 | ||
1322 | port = find_port_by_vq(vq->vdev->priv, vq); | |
1323 | if (!port) | |
1324 | return; | |
1325 | ||
1326 | spin_lock_irqsave(&port->inbuf_lock, flags); | |
d6933561 AS |
1327 | if (!port->inbuf) |
1328 | port->inbuf = get_inbuf(port); | |
17634ba2 | 1329 | |
88f251ac AS |
1330 | /* |
1331 | * Don't queue up data when port is closed. This condition | |
1332 | * can be reached when a console port is not yet connected (no | |
1333 | * tty is spawned) and the host sends out data to console | |
1334 | * ports. For generic serial ports, the host won't | |
1335 | * (shouldn't) send data till the guest is connected. | |
1336 | */ | |
1337 | if (!port->guest_connected) | |
1338 | discard_port_data(port); | |
1339 | ||
17634ba2 AS |
1340 | spin_unlock_irqrestore(&port->inbuf_lock, flags); |
1341 | ||
2030fa49 AS |
1342 | wake_up_interruptible(&port->waitqueue); |
1343 | ||
17634ba2 AS |
1344 | if (is_console_port(port) && hvc_poll(port->cons.hvc)) |
1345 | hvc_kick(); | |
1346 | } | |
1347 | ||
1348 | static void control_intr(struct virtqueue *vq) | |
1349 | { | |
1350 | struct ports_device *portdev; | |
1351 | ||
1352 | portdev = vq->vdev->priv; | |
1353 | schedule_work(&portdev->control_work); | |
1354 | } | |
1355 | ||
7f5d810d AS |
1356 | static void config_intr(struct virtio_device *vdev) |
1357 | { | |
1358 | struct ports_device *portdev; | |
1359 | ||
1360 | portdev = vdev->priv; | |
99f905f8 | 1361 | |
4038f5b7 | 1362 | if (!use_multiport(portdev)) { |
9778829c AS |
1363 | struct port *port; |
1364 | u16 rows, cols; | |
1365 | ||
1366 | vdev->config->get(vdev, | |
1367 | offsetof(struct virtio_console_config, cols), | |
1368 | &cols, sizeof(u16)); | |
1369 | vdev->config->get(vdev, | |
1370 | offsetof(struct virtio_console_config, rows), | |
1371 | &rows, sizeof(u16)); | |
1372 | ||
1373 | port = find_port_by_id(portdev, 0); | |
1374 | set_console_size(port, rows, cols); | |
1375 | ||
4038f5b7 AS |
1376 | /* |
1377 | * We'll use this way of resizing only for legacy | |
1378 | * support. For newer userspace | |
1379 | * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages | |
1380 | * to indicate console size changes so that it can be | |
1381 | * done per-port. | |
1382 | */ | |
9778829c | 1383 | resize_console(port); |
4038f5b7 | 1384 | } |
7f5d810d AS |
1385 | } |
1386 | ||
2658a79a AS |
1387 | static int init_vqs(struct ports_device *portdev) |
1388 | { | |
1389 | vq_callback_t **io_callbacks; | |
1390 | char **io_names; | |
1391 | struct virtqueue **vqs; | |
17634ba2 | 1392 | u32 i, j, nr_ports, nr_queues; |
2658a79a AS |
1393 | int err; |
1394 | ||
17634ba2 AS |
1395 | nr_ports = portdev->config.max_nr_ports; |
1396 | nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2; | |
2658a79a AS |
1397 | |
1398 | vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL); | |
1399 | if (!vqs) { | |
1400 | err = -ENOMEM; | |
1401 | goto fail; | |
1402 | } | |
1403 | io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL); | |
1404 | if (!io_callbacks) { | |
1405 | err = -ENOMEM; | |
1406 | goto free_vqs; | |
1407 | } | |
1408 | io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL); | |
1409 | if (!io_names) { | |
1410 | err = -ENOMEM; | |
1411 | goto free_callbacks; | |
1412 | } | |
1413 | portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *), | |
1414 | GFP_KERNEL); | |
1415 | if (!portdev->in_vqs) { | |
1416 | err = -ENOMEM; | |
1417 | goto free_names; | |
1418 | } | |
1419 | portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *), | |
1420 | GFP_KERNEL); | |
1421 | if (!portdev->out_vqs) { | |
1422 | err = -ENOMEM; | |
1423 | goto free_invqs; | |
1424 | } | |
1425 | ||
17634ba2 AS |
1426 | /* |
1427 | * For backward compat (newer host but older guest), the host | |
1428 | * spawns a console port first and also inits the vqs for port | |
1429 | * 0 before others. | |
1430 | */ | |
1431 | j = 0; | |
1432 | io_callbacks[j] = in_intr; | |
1433 | io_callbacks[j + 1] = NULL; | |
1434 | io_names[j] = "input"; | |
1435 | io_names[j + 1] = "output"; | |
1436 | j += 2; | |
1437 | ||
1438 | if (use_multiport(portdev)) { | |
1439 | io_callbacks[j] = control_intr; | |
1440 | io_callbacks[j + 1] = NULL; | |
1441 | io_names[j] = "control-i"; | |
1442 | io_names[j + 1] = "control-o"; | |
1443 | ||
1444 | for (i = 1; i < nr_ports; i++) { | |
1445 | j += 2; | |
1446 | io_callbacks[j] = in_intr; | |
1447 | io_callbacks[j + 1] = NULL; | |
1448 | io_names[j] = "input"; | |
1449 | io_names[j + 1] = "output"; | |
1450 | } | |
1451 | } | |
2658a79a AS |
1452 | /* Find the queues. */ |
1453 | err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs, | |
1454 | io_callbacks, | |
1455 | (const char **)io_names); | |
1456 | if (err) | |
1457 | goto free_outvqs; | |
1458 | ||
17634ba2 | 1459 | j = 0; |
2658a79a AS |
1460 | portdev->in_vqs[0] = vqs[0]; |
1461 | portdev->out_vqs[0] = vqs[1]; | |
17634ba2 AS |
1462 | j += 2; |
1463 | if (use_multiport(portdev)) { | |
1464 | portdev->c_ivq = vqs[j]; | |
1465 | portdev->c_ovq = vqs[j + 1]; | |
1466 | ||
1467 | for (i = 1; i < nr_ports; i++) { | |
1468 | j += 2; | |
1469 | portdev->in_vqs[i] = vqs[j]; | |
1470 | portdev->out_vqs[i] = vqs[j + 1]; | |
1471 | } | |
1472 | } | |
2658a79a AS |
1473 | kfree(io_callbacks); |
1474 | kfree(io_names); | |
1475 | kfree(vqs); | |
1476 | ||
1477 | return 0; | |
1478 | ||
1479 | free_names: | |
1480 | kfree(io_names); | |
1481 | free_callbacks: | |
1482 | kfree(io_callbacks); | |
1483 | free_outvqs: | |
1484 | kfree(portdev->out_vqs); | |
1485 | free_invqs: | |
1486 | kfree(portdev->in_vqs); | |
1487 | free_vqs: | |
1488 | kfree(vqs); | |
1489 | fail: | |
1490 | return err; | |
1491 | } | |
1492 | ||
fb08bd27 AS |
1493 | static const struct file_operations portdev_fops = { |
1494 | .owner = THIS_MODULE, | |
1495 | }; | |
1496 | ||
1c85bf35 AS |
1497 | /* |
1498 | * Once we're further in boot, we get probed like any other virtio | |
1499 | * device. | |
17634ba2 AS |
1500 | * |
1501 | * If the host also supports multiple console ports, we check the | |
1502 | * config space to see how many ports the host has spawned. We | |
1503 | * initialize each port found. | |
1c85bf35 AS |
1504 | */ |
1505 | static int __devinit virtcons_probe(struct virtio_device *vdev) | |
1506 | { | |
1c85bf35 AS |
1507 | struct ports_device *portdev; |
1508 | int err; | |
17634ba2 | 1509 | bool multiport; |
1c85bf35 AS |
1510 | |
1511 | portdev = kmalloc(sizeof(*portdev), GFP_KERNEL); | |
1512 | if (!portdev) { | |
1513 | err = -ENOMEM; | |
1514 | goto fail; | |
1515 | } | |
1516 | ||
1517 | /* Attach this portdev to this virtio_device, and vice-versa. */ | |
1518 | portdev->vdev = vdev; | |
1519 | vdev->priv = portdev; | |
1520 | ||
fb08bd27 AS |
1521 | spin_lock_irq(&pdrvdata_lock); |
1522 | portdev->drv_index = pdrvdata.index++; | |
1523 | spin_unlock_irq(&pdrvdata_lock); | |
1524 | ||
1525 | portdev->chr_major = register_chrdev(0, "virtio-portsdev", | |
1526 | &portdev_fops); | |
1527 | if (portdev->chr_major < 0) { | |
1528 | dev_err(&vdev->dev, | |
1529 | "Error %d registering chrdev for device %u\n", | |
1530 | portdev->chr_major, portdev->drv_index); | |
1531 | err = portdev->chr_major; | |
1532 | goto free; | |
1533 | } | |
1534 | ||
17634ba2 | 1535 | multiport = false; |
17634ba2 AS |
1536 | portdev->config.max_nr_ports = 1; |
1537 | if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) { | |
1538 | multiport = true; | |
1539 | vdev->features[0] |= 1 << VIRTIO_CONSOLE_F_MULTIPORT; | |
1540 | ||
b99fa815 AS |
1541 | vdev->config->get(vdev, offsetof(struct virtio_console_config, |
1542 | max_nr_ports), | |
17634ba2 AS |
1543 | &portdev->config.max_nr_ports, |
1544 | sizeof(portdev->config.max_nr_ports)); | |
17634ba2 AS |
1545 | } |
1546 | ||
1547 | /* Let the Host know we support multiple ports.*/ | |
1548 | vdev->config->finalize_features(vdev); | |
1549 | ||
2658a79a AS |
1550 | err = init_vqs(portdev); |
1551 | if (err < 0) { | |
1552 | dev_err(&vdev->dev, "Error %d initializing vqs\n", err); | |
fb08bd27 | 1553 | goto free_chrdev; |
2658a79a | 1554 | } |
1c85bf35 | 1555 | |
17634ba2 AS |
1556 | spin_lock_init(&portdev->ports_lock); |
1557 | INIT_LIST_HEAD(&portdev->ports); | |
1558 | ||
1559 | if (multiport) { | |
335a64a5 AS |
1560 | unsigned int nr_added_bufs; |
1561 | ||
17634ba2 AS |
1562 | spin_lock_init(&portdev->cvq_lock); |
1563 | INIT_WORK(&portdev->control_work, &control_work_handler); | |
1564 | ||
335a64a5 AS |
1565 | nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock); |
1566 | if (!nr_added_bufs) { | |
22a29eac AS |
1567 | dev_err(&vdev->dev, |
1568 | "Error allocating buffers for control queue\n"); | |
1569 | err = -ENOMEM; | |
1570 | goto free_vqs; | |
1571 | } | |
1d05160b AS |
1572 | } else { |
1573 | /* | |
1574 | * For backward compatibility: Create a console port | |
1575 | * if we're running on older host. | |
1576 | */ | |
1577 | add_port(portdev, 0); | |
17634ba2 AS |
1578 | } |
1579 | ||
f909f850 AS |
1580 | __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID, |
1581 | VIRTIO_CONSOLE_DEVICE_READY, 1); | |
31610434 RR |
1582 | return 0; |
1583 | ||
22a29eac | 1584 | free_vqs: |
0643e4c6 JL |
1585 | /* The host might want to notify mgmt sw about device add failure */ |
1586 | __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID, | |
1587 | VIRTIO_CONSOLE_DEVICE_READY, 0); | |
22a29eac AS |
1588 | vdev->config->del_vqs(vdev); |
1589 | kfree(portdev->in_vqs); | |
1590 | kfree(portdev->out_vqs); | |
fb08bd27 AS |
1591 | free_chrdev: |
1592 | unregister_chrdev(portdev->chr_major, "virtio-portsdev"); | |
31610434 | 1593 | free: |
1c85bf35 | 1594 | kfree(portdev); |
31610434 RR |
1595 | fail: |
1596 | return err; | |
1597 | } | |
1598 | ||
7177876f AS |
1599 | static void virtcons_remove(struct virtio_device *vdev) |
1600 | { | |
1601 | struct ports_device *portdev; | |
1602 | struct port *port, *port2; | |
1603 | struct port_buffer *buf; | |
1604 | unsigned int len; | |
1605 | ||
1606 | portdev = vdev->priv; | |
1607 | ||
02238959 AS |
1608 | /* Disable interrupts for vqs */ |
1609 | vdev->config->reset(vdev); | |
1610 | /* Finish up work that's lined up */ | |
7177876f | 1611 | cancel_work_sync(&portdev->control_work); |
7177876f AS |
1612 | |
1613 | list_for_each_entry_safe(port, port2, &portdev->ports, list) | |
1614 | remove_port(port); | |
1615 | ||
1616 | unregister_chrdev(portdev->chr_major, "virtio-portsdev"); | |
1617 | ||
505b0451 | 1618 | while ((buf = virtqueue_get_buf(portdev->c_ivq, &len))) |
7177876f AS |
1619 | free_buf(buf); |
1620 | ||
505b0451 | 1621 | while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq))) |
7177876f AS |
1622 | free_buf(buf); |
1623 | ||
1624 | vdev->config->del_vqs(vdev); | |
1625 | kfree(portdev->in_vqs); | |
1626 | kfree(portdev->out_vqs); | |
1627 | ||
1628 | kfree(portdev); | |
1629 | } | |
1630 | ||
31610434 RR |
1631 | static struct virtio_device_id id_table[] = { |
1632 | { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID }, | |
1633 | { 0 }, | |
1634 | }; | |
1635 | ||
c2983458 CB |
1636 | static unsigned int features[] = { |
1637 | VIRTIO_CONSOLE_F_SIZE, | |
b99fa815 | 1638 | VIRTIO_CONSOLE_F_MULTIPORT, |
c2983458 CB |
1639 | }; |
1640 | ||
31610434 | 1641 | static struct virtio_driver virtio_console = { |
c2983458 CB |
1642 | .feature_table = features, |
1643 | .feature_table_size = ARRAY_SIZE(features), | |
31610434 RR |
1644 | .driver.name = KBUILD_MODNAME, |
1645 | .driver.owner = THIS_MODULE, | |
1646 | .id_table = id_table, | |
1647 | .probe = virtcons_probe, | |
7177876f | 1648 | .remove = virtcons_remove, |
7f5d810d | 1649 | .config_changed = config_intr, |
31610434 RR |
1650 | }; |
1651 | ||
1652 | static int __init init(void) | |
1653 | { | |
fb08bd27 AS |
1654 | int err; |
1655 | ||
1656 | pdrvdata.class = class_create(THIS_MODULE, "virtio-ports"); | |
1657 | if (IS_ERR(pdrvdata.class)) { | |
1658 | err = PTR_ERR(pdrvdata.class); | |
1659 | pr_err("Error %d creating virtio-ports class\n", err); | |
1660 | return err; | |
1661 | } | |
d99393ef AS |
1662 | |
1663 | pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL); | |
1664 | if (!pdrvdata.debugfs_dir) { | |
1665 | pr_warning("Error %ld creating debugfs dir for virtio-ports\n", | |
1666 | PTR_ERR(pdrvdata.debugfs_dir)); | |
1667 | } | |
38edf58d AS |
1668 | INIT_LIST_HEAD(&pdrvdata.consoles); |
1669 | ||
31610434 RR |
1670 | return register_virtio_driver(&virtio_console); |
1671 | } | |
7177876f AS |
1672 | |
1673 | static void __exit fini(void) | |
1674 | { | |
1675 | unregister_virtio_driver(&virtio_console); | |
1676 | ||
1677 | class_destroy(pdrvdata.class); | |
1678 | if (pdrvdata.debugfs_dir) | |
1679 | debugfs_remove_recursive(pdrvdata.debugfs_dir); | |
1680 | } | |
31610434 | 1681 | module_init(init); |
7177876f | 1682 | module_exit(fini); |
31610434 RR |
1683 | |
1684 | MODULE_DEVICE_TABLE(virtio, id_table); | |
1685 | MODULE_DESCRIPTION("Virtio console driver"); | |
1686 | MODULE_LICENSE("GPL"); |