Commit | Line | Data |
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a23ea924 RR |
1 | /* |
2 | * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation | |
5084f893 AS |
3 | * Copyright (C) 2009, 2010, 2011 Red Hat, Inc. |
4 | * Copyright (C) 2009, 2010, 2011 Amit Shah <amit.shah@redhat.com> | |
31610434 RR |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
19 | */ | |
fb08bd27 | 20 | #include <linux/cdev.h> |
d99393ef | 21 | #include <linux/debugfs.h> |
5e38483b | 22 | #include <linux/completion.h> |
fb08bd27 | 23 | #include <linux/device.h> |
31610434 | 24 | #include <linux/err.h> |
a08fa92d | 25 | #include <linux/freezer.h> |
2030fa49 | 26 | #include <linux/fs.h> |
eb5e89fc MH |
27 | #include <linux/splice.h> |
28 | #include <linux/pagemap.h> | |
31610434 | 29 | #include <linux/init.h> |
38edf58d | 30 | #include <linux/list.h> |
2030fa49 AS |
31 | #include <linux/poll.h> |
32 | #include <linux/sched.h> | |
5a0e3ad6 | 33 | #include <linux/slab.h> |
38edf58d | 34 | #include <linux/spinlock.h> |
31610434 RR |
35 | #include <linux/virtio.h> |
36 | #include <linux/virtio_console.h> | |
2030fa49 | 37 | #include <linux/wait.h> |
17634ba2 | 38 | #include <linux/workqueue.h> |
c22405c9 | 39 | #include <linux/module.h> |
51df0acc | 40 | #include "../tty/hvc/hvc_console.h" |
31610434 | 41 | |
38edf58d AS |
42 | /* |
43 | * This is a global struct for storing common data for all the devices | |
44 | * this driver handles. | |
45 | * | |
46 | * Mainly, it has a linked list for all the consoles in one place so | |
47 | * that callbacks from hvc for get_chars(), put_chars() work properly | |
48 | * across multiple devices and multiple ports per device. | |
49 | */ | |
50 | struct ports_driver_data { | |
fb08bd27 AS |
51 | /* Used for registering chardevs */ |
52 | struct class *class; | |
53 | ||
d99393ef AS |
54 | /* Used for exporting per-port information to debugfs */ |
55 | struct dentry *debugfs_dir; | |
56 | ||
6bdf2afd AS |
57 | /* List of all the devices we're handling */ |
58 | struct list_head portdevs; | |
59 | ||
fb08bd27 AS |
60 | /* Number of devices this driver is handling */ |
61 | unsigned int index; | |
62 | ||
d8a02bd5 RR |
63 | /* |
64 | * This is used to keep track of the number of hvc consoles | |
65 | * spawned by this driver. This number is given as the first | |
66 | * argument to hvc_alloc(). To correctly map an initial | |
67 | * console spawned via hvc_instantiate to the console being | |
68 | * hooked up via hvc_alloc, we need to pass the same vtermno. | |
69 | * | |
70 | * We also just assume the first console being initialised was | |
71 | * the first one that got used as the initial console. | |
72 | */ | |
73 | unsigned int next_vtermno; | |
74 | ||
38edf58d AS |
75 | /* All the console devices handled by this driver */ |
76 | struct list_head consoles; | |
77 | }; | |
78 | static struct ports_driver_data pdrvdata; | |
79 | ||
80 | DEFINE_SPINLOCK(pdrvdata_lock); | |
5e38483b | 81 | DECLARE_COMPLETION(early_console_added); |
38edf58d | 82 | |
4f23c573 AS |
83 | /* This struct holds information that's relevant only for console ports */ |
84 | struct console { | |
85 | /* We'll place all consoles in a list in the pdrvdata struct */ | |
86 | struct list_head list; | |
87 | ||
88 | /* The hvc device associated with this console port */ | |
89 | struct hvc_struct *hvc; | |
90 | ||
9778829c AS |
91 | /* The size of the console */ |
92 | struct winsize ws; | |
93 | ||
4f23c573 AS |
94 | /* |
95 | * This number identifies the number that we used to register | |
96 | * with hvc in hvc_instantiate() and hvc_alloc(); this is the | |
97 | * number passed on by the hvc callbacks to us to | |
98 | * differentiate between the other console ports handled by | |
99 | * this driver | |
100 | */ | |
101 | u32 vtermno; | |
102 | }; | |
103 | ||
fdb9a054 AS |
104 | struct port_buffer { |
105 | char *buf; | |
106 | ||
107 | /* size of the buffer in *buf above */ | |
108 | size_t size; | |
109 | ||
110 | /* used length of the buffer */ | |
111 | size_t len; | |
112 | /* offset in the buf from which to consume data */ | |
113 | size_t offset; | |
114 | }; | |
115 | ||
17634ba2 AS |
116 | /* |
117 | * This is a per-device struct that stores data common to all the | |
118 | * ports for that device (vdev->priv). | |
119 | */ | |
120 | struct ports_device { | |
6bdf2afd AS |
121 | /* Next portdev in the list, head is in the pdrvdata struct */ |
122 | struct list_head list; | |
123 | ||
17634ba2 AS |
124 | /* |
125 | * Workqueue handlers where we process deferred work after | |
126 | * notification | |
127 | */ | |
128 | struct work_struct control_work; | |
129 | ||
130 | struct list_head ports; | |
131 | ||
132 | /* To protect the list of ports */ | |
133 | spinlock_t ports_lock; | |
134 | ||
135 | /* To protect the vq operations for the control channel */ | |
136 | spinlock_t cvq_lock; | |
137 | ||
138 | /* The current config space is stored here */ | |
b99fa815 | 139 | struct virtio_console_config config; |
17634ba2 AS |
140 | |
141 | /* The virtio device we're associated with */ | |
142 | struct virtio_device *vdev; | |
143 | ||
144 | /* | |
145 | * A couple of virtqueues for the control channel: one for | |
146 | * guest->host transfers, one for host->guest transfers | |
147 | */ | |
148 | struct virtqueue *c_ivq, *c_ovq; | |
149 | ||
150 | /* Array of per-port IO virtqueues */ | |
151 | struct virtqueue **in_vqs, **out_vqs; | |
fb08bd27 AS |
152 | |
153 | /* Used for numbering devices for sysfs and debugfs */ | |
154 | unsigned int drv_index; | |
155 | ||
156 | /* Major number for this device. Ports will be created as minors. */ | |
157 | int chr_major; | |
17634ba2 AS |
158 | }; |
159 | ||
17e5b4f2 AS |
160 | struct port_stats { |
161 | unsigned long bytes_sent, bytes_received, bytes_discarded; | |
162 | }; | |
163 | ||
1c85bf35 | 164 | /* This struct holds the per-port data */ |
21206ede | 165 | struct port { |
17634ba2 AS |
166 | /* Next port in the list, head is in the ports_device */ |
167 | struct list_head list; | |
168 | ||
1c85bf35 AS |
169 | /* Pointer to the parent virtio_console device */ |
170 | struct ports_device *portdev; | |
fdb9a054 AS |
171 | |
172 | /* The current buffer from which data has to be fed to readers */ | |
173 | struct port_buffer *inbuf; | |
21206ede | 174 | |
203baab8 AS |
175 | /* |
176 | * To protect the operations on the in_vq associated with this | |
177 | * port. Has to be a spinlock because it can be called from | |
178 | * interrupt context (get_char()). | |
179 | */ | |
180 | spinlock_t inbuf_lock; | |
181 | ||
cdfadfc1 AS |
182 | /* Protect the operations on the out_vq. */ |
183 | spinlock_t outvq_lock; | |
184 | ||
1c85bf35 AS |
185 | /* The IO vqs for this port */ |
186 | struct virtqueue *in_vq, *out_vq; | |
187 | ||
d99393ef AS |
188 | /* File in the debugfs directory that exposes this port's information */ |
189 | struct dentry *debugfs_file; | |
190 | ||
17e5b4f2 AS |
191 | /* |
192 | * Keep count of the bytes sent, received and discarded for | |
193 | * this port for accounting and debugging purposes. These | |
194 | * counts are not reset across port open / close events. | |
195 | */ | |
196 | struct port_stats stats; | |
197 | ||
4f23c573 AS |
198 | /* |
199 | * The entries in this struct will be valid if this port is | |
200 | * hooked up to an hvc console | |
201 | */ | |
202 | struct console cons; | |
17634ba2 | 203 | |
fb08bd27 | 204 | /* Each port associates with a separate char device */ |
d22a6989 | 205 | struct cdev *cdev; |
fb08bd27 AS |
206 | struct device *dev; |
207 | ||
b353a6b8 AS |
208 | /* Reference-counting to handle port hot-unplugs and file operations */ |
209 | struct kref kref; | |
210 | ||
2030fa49 AS |
211 | /* A waitqueue for poll() or blocking read operations */ |
212 | wait_queue_head_t waitqueue; | |
213 | ||
431edb8a AS |
214 | /* The 'name' of the port that we expose via sysfs properties */ |
215 | char *name; | |
216 | ||
3eae0ade AS |
217 | /* We can notify apps of host connect / disconnect events via SIGIO */ |
218 | struct fasync_struct *async_queue; | |
219 | ||
17634ba2 AS |
220 | /* The 'id' to identify the port with the Host */ |
221 | u32 id; | |
2030fa49 | 222 | |
cdfadfc1 AS |
223 | bool outvq_full; |
224 | ||
2030fa49 AS |
225 | /* Is the host device open */ |
226 | bool host_connected; | |
3c7969cc AS |
227 | |
228 | /* We should allow only one process to open a port */ | |
229 | bool guest_connected; | |
21206ede | 230 | }; |
31610434 | 231 | |
971f3390 RR |
232 | /* This is the very early arch-specified put chars function. */ |
233 | static int (*early_put_chars)(u32, const char *, int); | |
234 | ||
38edf58d AS |
235 | static struct port *find_port_by_vtermno(u32 vtermno) |
236 | { | |
237 | struct port *port; | |
4f23c573 | 238 | struct console *cons; |
38edf58d AS |
239 | unsigned long flags; |
240 | ||
241 | spin_lock_irqsave(&pdrvdata_lock, flags); | |
4f23c573 AS |
242 | list_for_each_entry(cons, &pdrvdata.consoles, list) { |
243 | if (cons->vtermno == vtermno) { | |
244 | port = container_of(cons, struct port, cons); | |
38edf58d | 245 | goto out; |
4f23c573 | 246 | } |
38edf58d AS |
247 | } |
248 | port = NULL; | |
249 | out: | |
250 | spin_unlock_irqrestore(&pdrvdata_lock, flags); | |
251 | return port; | |
252 | } | |
253 | ||
04950cdf AS |
254 | static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev, |
255 | dev_t dev) | |
256 | { | |
257 | struct port *port; | |
258 | unsigned long flags; | |
259 | ||
260 | spin_lock_irqsave(&portdev->ports_lock, flags); | |
261 | list_for_each_entry(port, &portdev->ports, list) | |
d22a6989 | 262 | if (port->cdev->dev == dev) |
04950cdf AS |
263 | goto out; |
264 | port = NULL; | |
265 | out: | |
266 | spin_unlock_irqrestore(&portdev->ports_lock, flags); | |
267 | ||
268 | return port; | |
269 | } | |
270 | ||
271 | static struct port *find_port_by_devt(dev_t dev) | |
272 | { | |
273 | struct ports_device *portdev; | |
274 | struct port *port; | |
275 | unsigned long flags; | |
276 | ||
277 | spin_lock_irqsave(&pdrvdata_lock, flags); | |
278 | list_for_each_entry(portdev, &pdrvdata.portdevs, list) { | |
279 | port = find_port_by_devt_in_portdev(portdev, dev); | |
280 | if (port) | |
281 | goto out; | |
282 | } | |
283 | port = NULL; | |
284 | out: | |
285 | spin_unlock_irqrestore(&pdrvdata_lock, flags); | |
286 | return port; | |
287 | } | |
288 | ||
17634ba2 AS |
289 | static struct port *find_port_by_id(struct ports_device *portdev, u32 id) |
290 | { | |
291 | struct port *port; | |
292 | unsigned long flags; | |
293 | ||
294 | spin_lock_irqsave(&portdev->ports_lock, flags); | |
295 | list_for_each_entry(port, &portdev->ports, list) | |
296 | if (port->id == id) | |
297 | goto out; | |
298 | port = NULL; | |
299 | out: | |
300 | spin_unlock_irqrestore(&portdev->ports_lock, flags); | |
301 | ||
302 | return port; | |
303 | } | |
304 | ||
203baab8 AS |
305 | static struct port *find_port_by_vq(struct ports_device *portdev, |
306 | struct virtqueue *vq) | |
307 | { | |
308 | struct port *port; | |
203baab8 AS |
309 | unsigned long flags; |
310 | ||
17634ba2 AS |
311 | spin_lock_irqsave(&portdev->ports_lock, flags); |
312 | list_for_each_entry(port, &portdev->ports, list) | |
203baab8 AS |
313 | if (port->in_vq == vq || port->out_vq == vq) |
314 | goto out; | |
203baab8 AS |
315 | port = NULL; |
316 | out: | |
17634ba2 | 317 | spin_unlock_irqrestore(&portdev->ports_lock, flags); |
203baab8 AS |
318 | return port; |
319 | } | |
320 | ||
17634ba2 AS |
321 | static bool is_console_port(struct port *port) |
322 | { | |
323 | if (port->cons.hvc) | |
324 | return true; | |
325 | return false; | |
326 | } | |
327 | ||
328 | static inline bool use_multiport(struct ports_device *portdev) | |
329 | { | |
330 | /* | |
331 | * This condition can be true when put_chars is called from | |
332 | * early_init | |
333 | */ | |
334 | if (!portdev->vdev) | |
335 | return 0; | |
336 | return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT); | |
337 | } | |
338 | ||
fdb9a054 AS |
339 | static void free_buf(struct port_buffer *buf) |
340 | { | |
341 | kfree(buf->buf); | |
342 | kfree(buf); | |
343 | } | |
344 | ||
345 | static struct port_buffer *alloc_buf(size_t buf_size) | |
346 | { | |
347 | struct port_buffer *buf; | |
348 | ||
349 | buf = kmalloc(sizeof(*buf), GFP_KERNEL); | |
350 | if (!buf) | |
351 | goto fail; | |
352 | buf->buf = kzalloc(buf_size, GFP_KERNEL); | |
353 | if (!buf->buf) | |
354 | goto free_buf; | |
355 | buf->len = 0; | |
356 | buf->offset = 0; | |
357 | buf->size = buf_size; | |
358 | return buf; | |
359 | ||
360 | free_buf: | |
361 | kfree(buf); | |
362 | fail: | |
363 | return NULL; | |
364 | } | |
365 | ||
a3cde449 | 366 | /* Callers should take appropriate locks */ |
defde669 | 367 | static struct port_buffer *get_inbuf(struct port *port) |
a3cde449 AS |
368 | { |
369 | struct port_buffer *buf; | |
a3cde449 AS |
370 | unsigned int len; |
371 | ||
d25a9dda AS |
372 | if (port->inbuf) |
373 | return port->inbuf; | |
374 | ||
375 | buf = virtqueue_get_buf(port->in_vq, &len); | |
a3cde449 AS |
376 | if (buf) { |
377 | buf->len = len; | |
378 | buf->offset = 0; | |
17e5b4f2 | 379 | port->stats.bytes_received += len; |
a3cde449 AS |
380 | } |
381 | return buf; | |
382 | } | |
383 | ||
e27b5198 AS |
384 | /* |
385 | * Create a scatter-gather list representing our input buffer and put | |
386 | * it in the queue. | |
387 | * | |
388 | * Callers should take appropriate locks. | |
389 | */ | |
203baab8 | 390 | static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf) |
e27b5198 AS |
391 | { |
392 | struct scatterlist sg[1]; | |
203baab8 | 393 | int ret; |
1c85bf35 | 394 | |
e27b5198 AS |
395 | sg_init_one(sg, buf->buf, buf->size); |
396 | ||
f96fde41 | 397 | ret = virtqueue_add_buf(vq, sg, 0, 1, buf, GFP_ATOMIC); |
505b0451 | 398 | virtqueue_kick(vq); |
49e86f16 AS |
399 | if (!ret) |
400 | ret = vq->num_free; | |
203baab8 AS |
401 | return ret; |
402 | } | |
403 | ||
88f251ac AS |
404 | /* Discard any unread data this port has. Callers lockers. */ |
405 | static void discard_port_data(struct port *port) | |
406 | { | |
407 | struct port_buffer *buf; | |
2d24cdaa | 408 | unsigned int err; |
88f251ac | 409 | |
d7a62cd0 AS |
410 | if (!port->portdev) { |
411 | /* Device has been unplugged. vqs are already gone. */ | |
412 | return; | |
413 | } | |
2d24cdaa | 414 | buf = get_inbuf(port); |
88f251ac | 415 | |
ce072a0c | 416 | err = 0; |
d6933561 | 417 | while (buf) { |
17e5b4f2 | 418 | port->stats.bytes_discarded += buf->len - buf->offset; |
2d24cdaa | 419 | if (add_inbuf(port->in_vq, buf) < 0) { |
ce072a0c | 420 | err++; |
d6933561 AS |
421 | free_buf(buf); |
422 | } | |
2d24cdaa AS |
423 | port->inbuf = NULL; |
424 | buf = get_inbuf(port); | |
88f251ac | 425 | } |
ce072a0c | 426 | if (err) |
d6933561 | 427 | dev_warn(port->dev, "Errors adding %d buffers back to vq\n", |
ce072a0c | 428 | err); |
88f251ac AS |
429 | } |
430 | ||
203baab8 AS |
431 | static bool port_has_data(struct port *port) |
432 | { | |
433 | unsigned long flags; | |
434 | bool ret; | |
435 | ||
d25a9dda | 436 | ret = false; |
203baab8 | 437 | spin_lock_irqsave(&port->inbuf_lock, flags); |
d6933561 | 438 | port->inbuf = get_inbuf(port); |
d25a9dda | 439 | if (port->inbuf) |
d6933561 | 440 | ret = true; |
d25a9dda | 441 | |
203baab8 | 442 | spin_unlock_irqrestore(&port->inbuf_lock, flags); |
203baab8 AS |
443 | return ret; |
444 | } | |
445 | ||
3425e706 AS |
446 | static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id, |
447 | unsigned int event, unsigned int value) | |
17634ba2 AS |
448 | { |
449 | struct scatterlist sg[1]; | |
450 | struct virtio_console_control cpkt; | |
451 | struct virtqueue *vq; | |
604b2ad7 | 452 | unsigned int len; |
17634ba2 | 453 | |
3425e706 | 454 | if (!use_multiport(portdev)) |
17634ba2 AS |
455 | return 0; |
456 | ||
3425e706 | 457 | cpkt.id = port_id; |
17634ba2 AS |
458 | cpkt.event = event; |
459 | cpkt.value = value; | |
460 | ||
3425e706 | 461 | vq = portdev->c_ovq; |
17634ba2 AS |
462 | |
463 | sg_init_one(sg, &cpkt, sizeof(cpkt)); | |
589575a2 | 464 | if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) == 0) { |
505b0451 MT |
465 | virtqueue_kick(vq); |
466 | while (!virtqueue_get_buf(vq, &len)) | |
17634ba2 AS |
467 | cpu_relax(); |
468 | } | |
469 | return 0; | |
470 | } | |
471 | ||
3425e706 AS |
472 | static ssize_t send_control_msg(struct port *port, unsigned int event, |
473 | unsigned int value) | |
474 | { | |
84ec06c5 AS |
475 | /* Did the port get unplugged before userspace closed it? */ |
476 | if (port->portdev) | |
477 | return __send_control_msg(port->portdev, port->id, event, value); | |
478 | return 0; | |
3425e706 AS |
479 | } |
480 | ||
eb5e89fc MH |
481 | struct buffer_token { |
482 | union { | |
483 | void *buf; | |
484 | struct scatterlist *sg; | |
485 | } u; | |
8ca84a50 MH |
486 | /* If sgpages == 0 then buf is used, else sg is used */ |
487 | unsigned int sgpages; | |
eb5e89fc MH |
488 | }; |
489 | ||
8ca84a50 | 490 | static void reclaim_sg_pages(struct scatterlist *sg, unsigned int nrpages) |
eb5e89fc MH |
491 | { |
492 | int i; | |
493 | struct page *page; | |
494 | ||
8ca84a50 | 495 | for (i = 0; i < nrpages; i++) { |
eb5e89fc MH |
496 | page = sg_page(&sg[i]); |
497 | if (!page) | |
498 | break; | |
499 | put_page(page); | |
500 | } | |
501 | kfree(sg); | |
502 | } | |
503 | ||
cdfadfc1 AS |
504 | /* Callers must take the port->outvq_lock */ |
505 | static void reclaim_consumed_buffers(struct port *port) | |
506 | { | |
eb5e89fc | 507 | struct buffer_token *tok; |
cdfadfc1 AS |
508 | unsigned int len; |
509 | ||
d7a62cd0 AS |
510 | if (!port->portdev) { |
511 | /* Device has been unplugged. vqs are already gone. */ | |
512 | return; | |
513 | } | |
eb5e89fc MH |
514 | while ((tok = virtqueue_get_buf(port->out_vq, &len))) { |
515 | if (tok->sgpages) | |
8ca84a50 | 516 | reclaim_sg_pages(tok->u.sg, tok->sgpages); |
eb5e89fc MH |
517 | else |
518 | kfree(tok->u.buf); | |
519 | kfree(tok); | |
cdfadfc1 AS |
520 | port->outvq_full = false; |
521 | } | |
522 | } | |
523 | ||
eb5e89fc MH |
524 | static ssize_t __send_to_port(struct port *port, struct scatterlist *sg, |
525 | int nents, size_t in_count, | |
526 | struct buffer_token *tok, bool nonblock) | |
f997f00b | 527 | { |
f997f00b | 528 | struct virtqueue *out_vq; |
589575a2 | 529 | int err; |
cdfadfc1 | 530 | unsigned long flags; |
f997f00b AS |
531 | unsigned int len; |
532 | ||
533 | out_vq = port->out_vq; | |
534 | ||
cdfadfc1 AS |
535 | spin_lock_irqsave(&port->outvq_lock, flags); |
536 | ||
537 | reclaim_consumed_buffers(port); | |
538 | ||
589575a2 | 539 | err = virtqueue_add_buf(out_vq, sg, nents, 0, tok, GFP_ATOMIC); |
f997f00b AS |
540 | |
541 | /* Tell Host to go! */ | |
505b0451 | 542 | virtqueue_kick(out_vq); |
f997f00b | 543 | |
589575a2 | 544 | if (err) { |
9ff4cfab | 545 | in_count = 0; |
cdfadfc1 | 546 | goto done; |
f997f00b AS |
547 | } |
548 | ||
589575a2 | 549 | if (out_vq->num_free == 0) |
cdfadfc1 AS |
550 | port->outvq_full = true; |
551 | ||
552 | if (nonblock) | |
553 | goto done; | |
554 | ||
555 | /* | |
556 | * Wait till the host acknowledges it pushed out the data we | |
531295e6 AS |
557 | * sent. This is done for data from the hvc_console; the tty |
558 | * operations are performed with spinlocks held so we can't | |
559 | * sleep here. An alternative would be to copy the data to a | |
560 | * buffer and relax the spinning requirement. The downside is | |
561 | * we need to kmalloc a GFP_ATOMIC buffer each time the | |
562 | * console driver writes something out. | |
cdfadfc1 | 563 | */ |
505b0451 | 564 | while (!virtqueue_get_buf(out_vq, &len)) |
f997f00b | 565 | cpu_relax(); |
cdfadfc1 AS |
566 | done: |
567 | spin_unlock_irqrestore(&port->outvq_lock, flags); | |
17e5b4f2 AS |
568 | |
569 | port->stats.bytes_sent += in_count; | |
cdfadfc1 AS |
570 | /* |
571 | * We're expected to return the amount of data we wrote -- all | |
572 | * of it | |
573 | */ | |
9ff4cfab | 574 | return in_count; |
f997f00b AS |
575 | } |
576 | ||
eb5e89fc MH |
577 | static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count, |
578 | bool nonblock) | |
579 | { | |
580 | struct scatterlist sg[1]; | |
581 | struct buffer_token *tok; | |
582 | ||
583 | tok = kmalloc(sizeof(*tok), GFP_ATOMIC); | |
584 | if (!tok) | |
585 | return -ENOMEM; | |
8ca84a50 | 586 | tok->sgpages = 0; |
eb5e89fc MH |
587 | tok->u.buf = in_buf; |
588 | ||
589 | sg_init_one(sg, in_buf, in_count); | |
590 | ||
591 | return __send_to_port(port, sg, 1, in_count, tok, nonblock); | |
592 | } | |
593 | ||
594 | static ssize_t send_pages(struct port *port, struct scatterlist *sg, int nents, | |
595 | size_t in_count, bool nonblock) | |
596 | { | |
597 | struct buffer_token *tok; | |
598 | ||
599 | tok = kmalloc(sizeof(*tok), GFP_ATOMIC); | |
600 | if (!tok) | |
601 | return -ENOMEM; | |
8ca84a50 | 602 | tok->sgpages = nents; |
eb5e89fc MH |
603 | tok->u.sg = sg; |
604 | ||
605 | return __send_to_port(port, sg, nents, in_count, tok, nonblock); | |
606 | } | |
607 | ||
203baab8 AS |
608 | /* |
609 | * Give out the data that's requested from the buffer that we have | |
610 | * queued up. | |
611 | */ | |
b766ceed AS |
612 | static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count, |
613 | bool to_user) | |
203baab8 AS |
614 | { |
615 | struct port_buffer *buf; | |
616 | unsigned long flags; | |
617 | ||
618 | if (!out_count || !port_has_data(port)) | |
619 | return 0; | |
620 | ||
621 | buf = port->inbuf; | |
b766ceed | 622 | out_count = min(out_count, buf->len - buf->offset); |
203baab8 | 623 | |
b766ceed AS |
624 | if (to_user) { |
625 | ssize_t ret; | |
626 | ||
627 | ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count); | |
628 | if (ret) | |
629 | return -EFAULT; | |
630 | } else { | |
631 | memcpy(out_buf, buf->buf + buf->offset, out_count); | |
632 | } | |
203baab8 | 633 | |
203baab8 AS |
634 | buf->offset += out_count; |
635 | ||
636 | if (buf->offset == buf->len) { | |
637 | /* | |
638 | * We're done using all the data in this buffer. | |
639 | * Re-queue so that the Host can send us more data. | |
640 | */ | |
641 | spin_lock_irqsave(&port->inbuf_lock, flags); | |
642 | port->inbuf = NULL; | |
643 | ||
644 | if (add_inbuf(port->in_vq, buf) < 0) | |
fb08bd27 | 645 | dev_warn(port->dev, "failed add_buf\n"); |
203baab8 AS |
646 | |
647 | spin_unlock_irqrestore(&port->inbuf_lock, flags); | |
648 | } | |
b766ceed | 649 | /* Return the number of bytes actually copied */ |
203baab8 | 650 | return out_count; |
e27b5198 AS |
651 | } |
652 | ||
2030fa49 | 653 | /* The condition that must be true for polling to end */ |
60caacd3 | 654 | static bool will_read_block(struct port *port) |
2030fa49 | 655 | { |
3709ea7a AS |
656 | if (!port->guest_connected) { |
657 | /* Port got hot-unplugged. Let's exit. */ | |
658 | return false; | |
659 | } | |
60caacd3 | 660 | return !port_has_data(port) && port->host_connected; |
2030fa49 AS |
661 | } |
662 | ||
cdfadfc1 AS |
663 | static bool will_write_block(struct port *port) |
664 | { | |
665 | bool ret; | |
666 | ||
60e5e0b8 AS |
667 | if (!port->guest_connected) { |
668 | /* Port got hot-unplugged. Let's exit. */ | |
669 | return false; | |
670 | } | |
cdfadfc1 AS |
671 | if (!port->host_connected) |
672 | return true; | |
673 | ||
674 | spin_lock_irq(&port->outvq_lock); | |
675 | /* | |
676 | * Check if the Host has consumed any buffers since we last | |
677 | * sent data (this is only applicable for nonblocking ports). | |
678 | */ | |
679 | reclaim_consumed_buffers(port); | |
680 | ret = port->outvq_full; | |
681 | spin_unlock_irq(&port->outvq_lock); | |
682 | ||
683 | return ret; | |
684 | } | |
685 | ||
2030fa49 AS |
686 | static ssize_t port_fops_read(struct file *filp, char __user *ubuf, |
687 | size_t count, loff_t *offp) | |
688 | { | |
689 | struct port *port; | |
690 | ssize_t ret; | |
691 | ||
692 | port = filp->private_data; | |
693 | ||
694 | if (!port_has_data(port)) { | |
695 | /* | |
696 | * If nothing's connected on the host just return 0 in | |
697 | * case of list_empty; this tells the userspace app | |
698 | * that there's no connection | |
699 | */ | |
700 | if (!port->host_connected) | |
701 | return 0; | |
702 | if (filp->f_flags & O_NONBLOCK) | |
703 | return -EAGAIN; | |
704 | ||
a08fa92d AS |
705 | ret = wait_event_freezable(port->waitqueue, |
706 | !will_read_block(port)); | |
2030fa49 AS |
707 | if (ret < 0) |
708 | return ret; | |
709 | } | |
b3dddb9e AS |
710 | /* Port got hot-unplugged. */ |
711 | if (!port->guest_connected) | |
712 | return -ENODEV; | |
2030fa49 AS |
713 | /* |
714 | * We could've received a disconnection message while we were | |
715 | * waiting for more data. | |
716 | * | |
717 | * This check is not clubbed in the if() statement above as we | |
718 | * might receive some data as well as the host could get | |
719 | * disconnected after we got woken up from our wait. So we | |
720 | * really want to give off whatever data we have and only then | |
721 | * check for host_connected. | |
722 | */ | |
723 | if (!port_has_data(port) && !port->host_connected) | |
724 | return 0; | |
725 | ||
726 | return fill_readbuf(port, ubuf, count, true); | |
727 | } | |
728 | ||
efe75d24 MH |
729 | static int wait_port_writable(struct port *port, bool nonblock) |
730 | { | |
731 | int ret; | |
732 | ||
733 | if (will_write_block(port)) { | |
734 | if (nonblock) | |
735 | return -EAGAIN; | |
736 | ||
737 | ret = wait_event_freezable(port->waitqueue, | |
738 | !will_write_block(port)); | |
739 | if (ret < 0) | |
740 | return ret; | |
741 | } | |
742 | /* Port got hot-unplugged. */ | |
743 | if (!port->guest_connected) | |
744 | return -ENODEV; | |
745 | ||
746 | return 0; | |
747 | } | |
748 | ||
2030fa49 AS |
749 | static ssize_t port_fops_write(struct file *filp, const char __user *ubuf, |
750 | size_t count, loff_t *offp) | |
751 | { | |
752 | struct port *port; | |
753 | char *buf; | |
754 | ssize_t ret; | |
cdfadfc1 | 755 | bool nonblock; |
2030fa49 | 756 | |
65745422 AS |
757 | /* Userspace could be out to fool us */ |
758 | if (!count) | |
759 | return 0; | |
760 | ||
2030fa49 AS |
761 | port = filp->private_data; |
762 | ||
cdfadfc1 AS |
763 | nonblock = filp->f_flags & O_NONBLOCK; |
764 | ||
efe75d24 MH |
765 | ret = wait_port_writable(port, nonblock); |
766 | if (ret < 0) | |
767 | return ret; | |
cdfadfc1 | 768 | |
2030fa49 AS |
769 | count = min((size_t)(32 * 1024), count); |
770 | ||
771 | buf = kmalloc(count, GFP_KERNEL); | |
772 | if (!buf) | |
773 | return -ENOMEM; | |
774 | ||
775 | ret = copy_from_user(buf, ubuf, count); | |
776 | if (ret) { | |
777 | ret = -EFAULT; | |
778 | goto free_buf; | |
779 | } | |
780 | ||
531295e6 AS |
781 | /* |
782 | * We now ask send_buf() to not spin for generic ports -- we | |
783 | * can re-use the same code path that non-blocking file | |
784 | * descriptors take for blocking file descriptors since the | |
785 | * wait is already done and we're certain the write will go | |
786 | * through to the host. | |
787 | */ | |
788 | nonblock = true; | |
cdfadfc1 AS |
789 | ret = send_buf(port, buf, count, nonblock); |
790 | ||
791 | if (nonblock && ret > 0) | |
792 | goto out; | |
793 | ||
2030fa49 AS |
794 | free_buf: |
795 | kfree(buf); | |
cdfadfc1 | 796 | out: |
2030fa49 AS |
797 | return ret; |
798 | } | |
799 | ||
eb5e89fc MH |
800 | struct sg_list { |
801 | unsigned int n; | |
8ca84a50 | 802 | unsigned int size; |
eb5e89fc MH |
803 | size_t len; |
804 | struct scatterlist *sg; | |
805 | }; | |
806 | ||
807 | static int pipe_to_sg(struct pipe_inode_info *pipe, struct pipe_buffer *buf, | |
808 | struct splice_desc *sd) | |
809 | { | |
810 | struct sg_list *sgl = sd->u.data; | |
ec8fc870 | 811 | unsigned int offset, len; |
eb5e89fc | 812 | |
8ca84a50 | 813 | if (sgl->n == sgl->size) |
eb5e89fc MH |
814 | return 0; |
815 | ||
816 | /* Try lock this page */ | |
817 | if (buf->ops->steal(pipe, buf) == 0) { | |
818 | /* Get reference and unlock page for moving */ | |
819 | get_page(buf->page); | |
820 | unlock_page(buf->page); | |
821 | ||
822 | len = min(buf->len, sd->len); | |
823 | sg_set_page(&(sgl->sg[sgl->n]), buf->page, len, buf->offset); | |
ec8fc870 MH |
824 | } else { |
825 | /* Failback to copying a page */ | |
826 | struct page *page = alloc_page(GFP_KERNEL); | |
827 | char *src = buf->ops->map(pipe, buf, 1); | |
828 | char *dst; | |
829 | ||
830 | if (!page) | |
831 | return -ENOMEM; | |
832 | dst = kmap(page); | |
833 | ||
834 | offset = sd->pos & ~PAGE_MASK; | |
835 | ||
836 | len = sd->len; | |
837 | if (len + offset > PAGE_SIZE) | |
838 | len = PAGE_SIZE - offset; | |
839 | ||
840 | memcpy(dst + offset, src + buf->offset, len); | |
841 | ||
842 | kunmap(page); | |
843 | buf->ops->unmap(pipe, buf, src); | |
844 | ||
845 | sg_set_page(&(sgl->sg[sgl->n]), page, len, offset); | |
eb5e89fc | 846 | } |
ec8fc870 MH |
847 | sgl->n++; |
848 | sgl->len += len; | |
eb5e89fc MH |
849 | |
850 | return len; | |
851 | } | |
852 | ||
853 | /* Faster zero-copy write by splicing */ | |
854 | static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe, | |
855 | struct file *filp, loff_t *ppos, | |
856 | size_t len, unsigned int flags) | |
857 | { | |
858 | struct port *port = filp->private_data; | |
859 | struct sg_list sgl; | |
860 | ssize_t ret; | |
861 | struct splice_desc sd = { | |
862 | .total_len = len, | |
863 | .flags = flags, | |
864 | .pos = *ppos, | |
865 | .u.data = &sgl, | |
866 | }; | |
867 | ||
efe75d24 MH |
868 | ret = wait_port_writable(port, filp->f_flags & O_NONBLOCK); |
869 | if (ret < 0) | |
870 | return ret; | |
871 | ||
eb5e89fc MH |
872 | sgl.n = 0; |
873 | sgl.len = 0; | |
8ca84a50 MH |
874 | sgl.size = pipe->nrbufs; |
875 | sgl.sg = kmalloc(sizeof(struct scatterlist) * sgl.size, GFP_KERNEL); | |
eb5e89fc MH |
876 | if (unlikely(!sgl.sg)) |
877 | return -ENOMEM; | |
878 | ||
8ca84a50 | 879 | sg_init_table(sgl.sg, sgl.size); |
eb5e89fc MH |
880 | ret = __splice_from_pipe(pipe, &sd, pipe_to_sg); |
881 | if (likely(ret > 0)) | |
882 | ret = send_pages(port, sgl.sg, sgl.n, sgl.len, true); | |
883 | ||
884 | return ret; | |
885 | } | |
886 | ||
2030fa49 AS |
887 | static unsigned int port_fops_poll(struct file *filp, poll_table *wait) |
888 | { | |
889 | struct port *port; | |
890 | unsigned int ret; | |
891 | ||
892 | port = filp->private_data; | |
893 | poll_wait(filp, &port->waitqueue, wait); | |
894 | ||
8529a504 AS |
895 | if (!port->guest_connected) { |
896 | /* Port got unplugged */ | |
897 | return POLLHUP; | |
898 | } | |
2030fa49 | 899 | ret = 0; |
6df7aadc | 900 | if (!will_read_block(port)) |
2030fa49 | 901 | ret |= POLLIN | POLLRDNORM; |
cdfadfc1 | 902 | if (!will_write_block(port)) |
2030fa49 AS |
903 | ret |= POLLOUT; |
904 | if (!port->host_connected) | |
905 | ret |= POLLHUP; | |
906 | ||
907 | return ret; | |
908 | } | |
909 | ||
b353a6b8 AS |
910 | static void remove_port(struct kref *kref); |
911 | ||
2030fa49 AS |
912 | static int port_fops_release(struct inode *inode, struct file *filp) |
913 | { | |
914 | struct port *port; | |
915 | ||
916 | port = filp->private_data; | |
917 | ||
918 | /* Notify host of port being closed */ | |
919 | send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0); | |
920 | ||
88f251ac | 921 | spin_lock_irq(&port->inbuf_lock); |
3c7969cc AS |
922 | port->guest_connected = false; |
923 | ||
88f251ac AS |
924 | discard_port_data(port); |
925 | ||
926 | spin_unlock_irq(&port->inbuf_lock); | |
927 | ||
cdfadfc1 AS |
928 | spin_lock_irq(&port->outvq_lock); |
929 | reclaim_consumed_buffers(port); | |
930 | spin_unlock_irq(&port->outvq_lock); | |
931 | ||
b353a6b8 AS |
932 | /* |
933 | * Locks aren't necessary here as a port can't be opened after | |
934 | * unplug, and if a port isn't unplugged, a kref would already | |
935 | * exist for the port. Plus, taking ports_lock here would | |
936 | * create a dependency on other locks taken by functions | |
937 | * inside remove_port if we're the last holder of the port, | |
938 | * creating many problems. | |
939 | */ | |
940 | kref_put(&port->kref, remove_port); | |
941 | ||
2030fa49 AS |
942 | return 0; |
943 | } | |
944 | ||
945 | static int port_fops_open(struct inode *inode, struct file *filp) | |
946 | { | |
947 | struct cdev *cdev = inode->i_cdev; | |
948 | struct port *port; | |
8ad37e83 | 949 | int ret; |
2030fa49 | 950 | |
04950cdf | 951 | port = find_port_by_devt(cdev->dev); |
2030fa49 AS |
952 | filp->private_data = port; |
953 | ||
b353a6b8 AS |
954 | /* Prevent against a port getting hot-unplugged at the same time */ |
955 | spin_lock_irq(&port->portdev->ports_lock); | |
956 | kref_get(&port->kref); | |
957 | spin_unlock_irq(&port->portdev->ports_lock); | |
958 | ||
2030fa49 AS |
959 | /* |
960 | * Don't allow opening of console port devices -- that's done | |
961 | * via /dev/hvc | |
962 | */ | |
8ad37e83 AS |
963 | if (is_console_port(port)) { |
964 | ret = -ENXIO; | |
965 | goto out; | |
966 | } | |
2030fa49 | 967 | |
3c7969cc AS |
968 | /* Allow only one process to open a particular port at a time */ |
969 | spin_lock_irq(&port->inbuf_lock); | |
970 | if (port->guest_connected) { | |
971 | spin_unlock_irq(&port->inbuf_lock); | |
8ad37e83 AS |
972 | ret = -EMFILE; |
973 | goto out; | |
3c7969cc AS |
974 | } |
975 | ||
976 | port->guest_connected = true; | |
977 | spin_unlock_irq(&port->inbuf_lock); | |
978 | ||
cdfadfc1 AS |
979 | spin_lock_irq(&port->outvq_lock); |
980 | /* | |
981 | * There might be a chance that we missed reclaiming a few | |
982 | * buffers in the window of the port getting previously closed | |
983 | * and opening now. | |
984 | */ | |
985 | reclaim_consumed_buffers(port); | |
986 | spin_unlock_irq(&port->outvq_lock); | |
987 | ||
299fb61c AS |
988 | nonseekable_open(inode, filp); |
989 | ||
2030fa49 AS |
990 | /* Notify host of port being opened */ |
991 | send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1); | |
992 | ||
993 | return 0; | |
8ad37e83 | 994 | out: |
b353a6b8 | 995 | kref_put(&port->kref, remove_port); |
8ad37e83 | 996 | return ret; |
2030fa49 AS |
997 | } |
998 | ||
3eae0ade AS |
999 | static int port_fops_fasync(int fd, struct file *filp, int mode) |
1000 | { | |
1001 | struct port *port; | |
1002 | ||
1003 | port = filp->private_data; | |
1004 | return fasync_helper(fd, filp, mode, &port->async_queue); | |
1005 | } | |
1006 | ||
2030fa49 AS |
1007 | /* |
1008 | * The file operations that we support: programs in the guest can open | |
1009 | * a console device, read from it, write to it, poll for data and | |
1010 | * close it. The devices are at | |
1011 | * /dev/vport<device number>p<port number> | |
1012 | */ | |
1013 | static const struct file_operations port_fops = { | |
1014 | .owner = THIS_MODULE, | |
1015 | .open = port_fops_open, | |
1016 | .read = port_fops_read, | |
1017 | .write = port_fops_write, | |
eb5e89fc | 1018 | .splice_write = port_fops_splice_write, |
2030fa49 AS |
1019 | .poll = port_fops_poll, |
1020 | .release = port_fops_release, | |
3eae0ade | 1021 | .fasync = port_fops_fasync, |
299fb61c | 1022 | .llseek = no_llseek, |
2030fa49 AS |
1023 | }; |
1024 | ||
a23ea924 RR |
1025 | /* |
1026 | * The put_chars() callback is pretty straightforward. | |
31610434 | 1027 | * |
a23ea924 RR |
1028 | * We turn the characters into a scatter-gather list, add it to the |
1029 | * output queue and then kick the Host. Then we sit here waiting for | |
1030 | * it to finish: inefficient in theory, but in practice | |
1031 | * implementations will do it immediately (lguest's Launcher does). | |
1032 | */ | |
31610434 RR |
1033 | static int put_chars(u32 vtermno, const char *buf, int count) |
1034 | { | |
21206ede | 1035 | struct port *port; |
38edf58d | 1036 | |
162a689a FD |
1037 | if (unlikely(early_put_chars)) |
1038 | return early_put_chars(vtermno, buf, count); | |
1039 | ||
38edf58d AS |
1040 | port = find_port_by_vtermno(vtermno); |
1041 | if (!port) | |
6dc69f97 | 1042 | return -EPIPE; |
31610434 | 1043 | |
cdfadfc1 | 1044 | return send_buf(port, (void *)buf, count, false); |
31610434 RR |
1045 | } |
1046 | ||
a23ea924 RR |
1047 | /* |
1048 | * get_chars() is the callback from the hvc_console infrastructure | |
1049 | * when an interrupt is received. | |
31610434 | 1050 | * |
203baab8 AS |
1051 | * We call out to fill_readbuf that gets us the required data from the |
1052 | * buffers that are queued up. | |
a23ea924 | 1053 | */ |
31610434 RR |
1054 | static int get_chars(u32 vtermno, char *buf, int count) |
1055 | { | |
21206ede RR |
1056 | struct port *port; |
1057 | ||
6dc69f97 AS |
1058 | /* If we've not set up the port yet, we have no input to give. */ |
1059 | if (unlikely(early_put_chars)) | |
1060 | return 0; | |
1061 | ||
38edf58d AS |
1062 | port = find_port_by_vtermno(vtermno); |
1063 | if (!port) | |
6dc69f97 | 1064 | return -EPIPE; |
21206ede | 1065 | |
31610434 | 1066 | /* If we don't have an input queue yet, we can't get input. */ |
21206ede | 1067 | BUG_ON(!port->in_vq); |
31610434 | 1068 | |
b766ceed | 1069 | return fill_readbuf(port, buf, count, false); |
31610434 | 1070 | } |
31610434 | 1071 | |
cb06e367 | 1072 | static void resize_console(struct port *port) |
c2983458 | 1073 | { |
cb06e367 | 1074 | struct virtio_device *vdev; |
c2983458 | 1075 | |
2de16a49 | 1076 | /* The port could have been hot-unplugged */ |
9778829c | 1077 | if (!port || !is_console_port(port)) |
2de16a49 AS |
1078 | return; |
1079 | ||
cb06e367 | 1080 | vdev = port->portdev->vdev; |
9778829c AS |
1081 | if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE)) |
1082 | hvc_resize(port->cons.hvc, port->cons.ws); | |
c2983458 CB |
1083 | } |
1084 | ||
38edf58d | 1085 | /* We set the configuration at this point, since we now have a tty */ |
91fcad19 CB |
1086 | static int notifier_add_vio(struct hvc_struct *hp, int data) |
1087 | { | |
38edf58d AS |
1088 | struct port *port; |
1089 | ||
1090 | port = find_port_by_vtermno(hp->vtermno); | |
1091 | if (!port) | |
1092 | return -EINVAL; | |
1093 | ||
91fcad19 | 1094 | hp->irq_requested = 1; |
cb06e367 | 1095 | resize_console(port); |
c2983458 | 1096 | |
91fcad19 CB |
1097 | return 0; |
1098 | } | |
1099 | ||
1100 | static void notifier_del_vio(struct hvc_struct *hp, int data) | |
1101 | { | |
1102 | hp->irq_requested = 0; | |
1103 | } | |
1104 | ||
17634ba2 | 1105 | /* The operations for console ports. */ |
1dff3996 | 1106 | static const struct hv_ops hv_ops = { |
971f3390 RR |
1107 | .get_chars = get_chars, |
1108 | .put_chars = put_chars, | |
1109 | .notifier_add = notifier_add_vio, | |
1110 | .notifier_del = notifier_del_vio, | |
1111 | .notifier_hangup = notifier_del_vio, | |
1112 | }; | |
1113 | ||
1114 | /* | |
1115 | * Console drivers are initialized very early so boot messages can go | |
1116 | * out, so we do things slightly differently from the generic virtio | |
1117 | * initialization of the net and block drivers. | |
1118 | * | |
1119 | * At this stage, the console is output-only. It's too early to set | |
1120 | * up a virtqueue, so we let the drivers do some boutique early-output | |
1121 | * thing. | |
1122 | */ | |
1123 | int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int)) | |
1124 | { | |
1125 | early_put_chars = put_chars; | |
1126 | return hvc_instantiate(0, 0, &hv_ops); | |
1127 | } | |
1128 | ||
17634ba2 | 1129 | int init_port_console(struct port *port) |
cfa6d379 AS |
1130 | { |
1131 | int ret; | |
1132 | ||
1133 | /* | |
1134 | * The Host's telling us this port is a console port. Hook it | |
1135 | * up with an hvc console. | |
1136 | * | |
1137 | * To set up and manage our virtual console, we call | |
1138 | * hvc_alloc(). | |
1139 | * | |
1140 | * The first argument of hvc_alloc() is the virtual console | |
1141 | * number. The second argument is the parameter for the | |
1142 | * notification mechanism (like irq number). We currently | |
1143 | * leave this as zero, virtqueues have implicit notifications. | |
1144 | * | |
1145 | * The third argument is a "struct hv_ops" containing the | |
1146 | * put_chars() get_chars(), notifier_add() and notifier_del() | |
1147 | * pointers. The final argument is the output buffer size: we | |
1148 | * can do any size, so we put PAGE_SIZE here. | |
1149 | */ | |
1150 | port->cons.vtermno = pdrvdata.next_vtermno; | |
1151 | ||
1152 | port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE); | |
1153 | if (IS_ERR(port->cons.hvc)) { | |
1154 | ret = PTR_ERR(port->cons.hvc); | |
298add72 AS |
1155 | dev_err(port->dev, |
1156 | "error %d allocating hvc for port\n", ret); | |
cfa6d379 AS |
1157 | port->cons.hvc = NULL; |
1158 | return ret; | |
1159 | } | |
1160 | spin_lock_irq(&pdrvdata_lock); | |
1161 | pdrvdata.next_vtermno++; | |
1162 | list_add_tail(&port->cons.list, &pdrvdata.consoles); | |
1163 | spin_unlock_irq(&pdrvdata_lock); | |
3c7969cc | 1164 | port->guest_connected = true; |
cfa6d379 | 1165 | |
1d05160b AS |
1166 | /* |
1167 | * Start using the new console output if this is the first | |
1168 | * console to come up. | |
1169 | */ | |
1170 | if (early_put_chars) | |
1171 | early_put_chars = NULL; | |
1172 | ||
2030fa49 AS |
1173 | /* Notify host of port being opened */ |
1174 | send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1); | |
1175 | ||
cfa6d379 AS |
1176 | return 0; |
1177 | } | |
1178 | ||
431edb8a AS |
1179 | static ssize_t show_port_name(struct device *dev, |
1180 | struct device_attribute *attr, char *buffer) | |
1181 | { | |
1182 | struct port *port; | |
1183 | ||
1184 | port = dev_get_drvdata(dev); | |
1185 | ||
1186 | return sprintf(buffer, "%s\n", port->name); | |
1187 | } | |
1188 | ||
1189 | static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL); | |
1190 | ||
1191 | static struct attribute *port_sysfs_entries[] = { | |
1192 | &dev_attr_name.attr, | |
1193 | NULL | |
1194 | }; | |
1195 | ||
1196 | static struct attribute_group port_attribute_group = { | |
1197 | .name = NULL, /* put in device directory */ | |
1198 | .attrs = port_sysfs_entries, | |
1199 | }; | |
1200 | ||
d99393ef AS |
1201 | static ssize_t debugfs_read(struct file *filp, char __user *ubuf, |
1202 | size_t count, loff_t *offp) | |
1203 | { | |
1204 | struct port *port; | |
1205 | char *buf; | |
1206 | ssize_t ret, out_offset, out_count; | |
1207 | ||
1208 | out_count = 1024; | |
1209 | buf = kmalloc(out_count, GFP_KERNEL); | |
1210 | if (!buf) | |
1211 | return -ENOMEM; | |
1212 | ||
1213 | port = filp->private_data; | |
1214 | out_offset = 0; | |
1215 | out_offset += snprintf(buf + out_offset, out_count, | |
1216 | "name: %s\n", port->name ? port->name : ""); | |
1217 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1218 | "guest_connected: %d\n", port->guest_connected); | |
1219 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1220 | "host_connected: %d\n", port->host_connected); | |
cdfadfc1 AS |
1221 | out_offset += snprintf(buf + out_offset, out_count - out_offset, |
1222 | "outvq_full: %d\n", port->outvq_full); | |
17e5b4f2 AS |
1223 | out_offset += snprintf(buf + out_offset, out_count - out_offset, |
1224 | "bytes_sent: %lu\n", port->stats.bytes_sent); | |
1225 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1226 | "bytes_received: %lu\n", | |
1227 | port->stats.bytes_received); | |
1228 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1229 | "bytes_discarded: %lu\n", | |
1230 | port->stats.bytes_discarded); | |
d99393ef AS |
1231 | out_offset += snprintf(buf + out_offset, out_count - out_offset, |
1232 | "is_console: %s\n", | |
1233 | is_console_port(port) ? "yes" : "no"); | |
1234 | out_offset += snprintf(buf + out_offset, out_count - out_offset, | |
1235 | "console_vtermno: %u\n", port->cons.vtermno); | |
1236 | ||
1237 | ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); | |
1238 | kfree(buf); | |
1239 | return ret; | |
1240 | } | |
1241 | ||
1242 | static const struct file_operations port_debugfs_ops = { | |
1243 | .owner = THIS_MODULE, | |
234e3405 | 1244 | .open = simple_open, |
d99393ef AS |
1245 | .read = debugfs_read, |
1246 | }; | |
1247 | ||
9778829c AS |
1248 | static void set_console_size(struct port *port, u16 rows, u16 cols) |
1249 | { | |
1250 | if (!port || !is_console_port(port)) | |
1251 | return; | |
1252 | ||
1253 | port->cons.ws.ws_row = rows; | |
1254 | port->cons.ws.ws_col = cols; | |
1255 | } | |
1256 | ||
c446f8fc AS |
1257 | static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock) |
1258 | { | |
1259 | struct port_buffer *buf; | |
1260 | unsigned int nr_added_bufs; | |
1261 | int ret; | |
1262 | ||
1263 | nr_added_bufs = 0; | |
1264 | do { | |
1265 | buf = alloc_buf(PAGE_SIZE); | |
1266 | if (!buf) | |
1267 | break; | |
1268 | ||
1269 | spin_lock_irq(lock); | |
1270 | ret = add_inbuf(vq, buf); | |
1271 | if (ret < 0) { | |
1272 | spin_unlock_irq(lock); | |
1273 | free_buf(buf); | |
1274 | break; | |
1275 | } | |
1276 | nr_added_bufs++; | |
1277 | spin_unlock_irq(lock); | |
1278 | } while (ret > 0); | |
1279 | ||
1280 | return nr_added_bufs; | |
1281 | } | |
1282 | ||
3eae0ade AS |
1283 | static void send_sigio_to_port(struct port *port) |
1284 | { | |
1285 | if (port->async_queue && port->guest_connected) | |
1286 | kill_fasync(&port->async_queue, SIGIO, POLL_OUT); | |
1287 | } | |
1288 | ||
c446f8fc AS |
1289 | static int add_port(struct ports_device *portdev, u32 id) |
1290 | { | |
1291 | char debugfs_name[16]; | |
1292 | struct port *port; | |
1293 | struct port_buffer *buf; | |
1294 | dev_t devt; | |
1295 | unsigned int nr_added_bufs; | |
1296 | int err; | |
1297 | ||
1298 | port = kmalloc(sizeof(*port), GFP_KERNEL); | |
1299 | if (!port) { | |
1300 | err = -ENOMEM; | |
1301 | goto fail; | |
1302 | } | |
b353a6b8 | 1303 | kref_init(&port->kref); |
c446f8fc AS |
1304 | |
1305 | port->portdev = portdev; | |
1306 | port->id = id; | |
1307 | ||
1308 | port->name = NULL; | |
1309 | port->inbuf = NULL; | |
1310 | port->cons.hvc = NULL; | |
3eae0ade | 1311 | port->async_queue = NULL; |
c446f8fc | 1312 | |
9778829c AS |
1313 | port->cons.ws.ws_row = port->cons.ws.ws_col = 0; |
1314 | ||
c446f8fc | 1315 | port->host_connected = port->guest_connected = false; |
17e5b4f2 | 1316 | port->stats = (struct port_stats) { 0 }; |
c446f8fc | 1317 | |
cdfadfc1 AS |
1318 | port->outvq_full = false; |
1319 | ||
c446f8fc AS |
1320 | port->in_vq = portdev->in_vqs[port->id]; |
1321 | port->out_vq = portdev->out_vqs[port->id]; | |
1322 | ||
d22a6989 AS |
1323 | port->cdev = cdev_alloc(); |
1324 | if (!port->cdev) { | |
1325 | dev_err(&port->portdev->vdev->dev, "Error allocating cdev\n"); | |
1326 | err = -ENOMEM; | |
1327 | goto free_port; | |
1328 | } | |
1329 | port->cdev->ops = &port_fops; | |
c446f8fc AS |
1330 | |
1331 | devt = MKDEV(portdev->chr_major, id); | |
d22a6989 | 1332 | err = cdev_add(port->cdev, devt, 1); |
c446f8fc AS |
1333 | if (err < 0) { |
1334 | dev_err(&port->portdev->vdev->dev, | |
1335 | "Error %d adding cdev for port %u\n", err, id); | |
d22a6989 | 1336 | goto free_cdev; |
c446f8fc AS |
1337 | } |
1338 | port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev, | |
1339 | devt, port, "vport%up%u", | |
1340 | port->portdev->drv_index, id); | |
1341 | if (IS_ERR(port->dev)) { | |
1342 | err = PTR_ERR(port->dev); | |
1343 | dev_err(&port->portdev->vdev->dev, | |
1344 | "Error %d creating device for port %u\n", | |
1345 | err, id); | |
1346 | goto free_cdev; | |
1347 | } | |
1348 | ||
1349 | spin_lock_init(&port->inbuf_lock); | |
cdfadfc1 | 1350 | spin_lock_init(&port->outvq_lock); |
c446f8fc AS |
1351 | init_waitqueue_head(&port->waitqueue); |
1352 | ||
1353 | /* Fill the in_vq with buffers so the host can send us data. */ | |
1354 | nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock); | |
1355 | if (!nr_added_bufs) { | |
1356 | dev_err(port->dev, "Error allocating inbufs\n"); | |
1357 | err = -ENOMEM; | |
1358 | goto free_device; | |
1359 | } | |
1360 | ||
1361 | /* | |
1362 | * If we're not using multiport support, this has to be a console port | |
1363 | */ | |
1364 | if (!use_multiport(port->portdev)) { | |
1365 | err = init_port_console(port); | |
1366 | if (err) | |
1367 | goto free_inbufs; | |
1368 | } | |
1369 | ||
1370 | spin_lock_irq(&portdev->ports_lock); | |
1371 | list_add_tail(&port->list, &port->portdev->ports); | |
1372 | spin_unlock_irq(&portdev->ports_lock); | |
1373 | ||
1374 | /* | |
1375 | * Tell the Host we're set so that it can send us various | |
1376 | * configuration parameters for this port (eg, port name, | |
1377 | * caching, whether this is a console port, etc.) | |
1378 | */ | |
1379 | send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1); | |
1380 | ||
1381 | if (pdrvdata.debugfs_dir) { | |
1382 | /* | |
1383 | * Finally, create the debugfs file that we can use to | |
1384 | * inspect a port's state at any time | |
1385 | */ | |
1386 | sprintf(debugfs_name, "vport%up%u", | |
1387 | port->portdev->drv_index, id); | |
1388 | port->debugfs_file = debugfs_create_file(debugfs_name, 0444, | |
1389 | pdrvdata.debugfs_dir, | |
1390 | port, | |
1391 | &port_debugfs_ops); | |
1392 | } | |
1393 | return 0; | |
1394 | ||
1395 | free_inbufs: | |
1396 | while ((buf = virtqueue_detach_unused_buf(port->in_vq))) | |
1397 | free_buf(buf); | |
1398 | free_device: | |
1399 | device_destroy(pdrvdata.class, port->dev->devt); | |
1400 | free_cdev: | |
d22a6989 | 1401 | cdev_del(port->cdev); |
c446f8fc AS |
1402 | free_port: |
1403 | kfree(port); | |
1404 | fail: | |
1405 | /* The host might want to notify management sw about port add failure */ | |
0643e4c6 | 1406 | __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0); |
c446f8fc AS |
1407 | return err; |
1408 | } | |
1409 | ||
b353a6b8 AS |
1410 | /* No users remain, remove all port-specific data. */ |
1411 | static void remove_port(struct kref *kref) | |
1412 | { | |
1413 | struct port *port; | |
1414 | ||
1415 | port = container_of(kref, struct port, kref); | |
1416 | ||
1417 | sysfs_remove_group(&port->dev->kobj, &port_attribute_group); | |
1418 | device_destroy(pdrvdata.class, port->dev->devt); | |
1419 | cdev_del(port->cdev); | |
1420 | ||
1421 | kfree(port->name); | |
1422 | ||
1423 | debugfs_remove(port->debugfs_file); | |
1424 | ||
1425 | kfree(port); | |
1426 | } | |
1427 | ||
a0e2dbfc AS |
1428 | static void remove_port_data(struct port *port) |
1429 | { | |
1430 | struct port_buffer *buf; | |
1431 | ||
1432 | /* Remove unused data this port might have received. */ | |
1433 | discard_port_data(port); | |
1434 | ||
1435 | reclaim_consumed_buffers(port); | |
1436 | ||
1437 | /* Remove buffers we queued up for the Host to send us data in. */ | |
1438 | while ((buf = virtqueue_detach_unused_buf(port->in_vq))) | |
1439 | free_buf(buf); | |
1440 | } | |
1441 | ||
b353a6b8 AS |
1442 | /* |
1443 | * Port got unplugged. Remove port from portdev's list and drop the | |
1444 | * kref reference. If no userspace has this port opened, it will | |
1445 | * result in immediate removal the port. | |
1446 | */ | |
1447 | static void unplug_port(struct port *port) | |
1f7aa42d | 1448 | { |
b353a6b8 AS |
1449 | spin_lock_irq(&port->portdev->ports_lock); |
1450 | list_del(&port->list); | |
1451 | spin_unlock_irq(&port->portdev->ports_lock); | |
1452 | ||
0047634d AS |
1453 | if (port->guest_connected) { |
1454 | port->guest_connected = false; | |
1455 | port->host_connected = false; | |
1456 | wake_up_interruptible(&port->waitqueue); | |
a461e11e AS |
1457 | |
1458 | /* Let the app know the port is going down. */ | |
1459 | send_sigio_to_port(port); | |
0047634d AS |
1460 | } |
1461 | ||
1f7aa42d AS |
1462 | if (is_console_port(port)) { |
1463 | spin_lock_irq(&pdrvdata_lock); | |
1464 | list_del(&port->cons.list); | |
1465 | spin_unlock_irq(&pdrvdata_lock); | |
1466 | hvc_remove(port->cons.hvc); | |
1467 | } | |
1f7aa42d | 1468 | |
a0e2dbfc | 1469 | remove_port_data(port); |
a9cdd485 | 1470 | |
b353a6b8 AS |
1471 | /* |
1472 | * We should just assume the device itself has gone off -- | |
1473 | * else a close on an open port later will try to send out a | |
1474 | * control message. | |
1475 | */ | |
1476 | port->portdev = NULL; | |
d99393ef | 1477 | |
b353a6b8 AS |
1478 | /* |
1479 | * Locks around here are not necessary - a port can't be | |
1480 | * opened after we removed the port struct from ports_list | |
1481 | * above. | |
1482 | */ | |
1483 | kref_put(&port->kref, remove_port); | |
1f7aa42d AS |
1484 | } |
1485 | ||
17634ba2 AS |
1486 | /* Any private messages that the Host and Guest want to share */ |
1487 | static void handle_control_message(struct ports_device *portdev, | |
1488 | struct port_buffer *buf) | |
1489 | { | |
1490 | struct virtio_console_control *cpkt; | |
1491 | struct port *port; | |
431edb8a AS |
1492 | size_t name_size; |
1493 | int err; | |
17634ba2 AS |
1494 | |
1495 | cpkt = (struct virtio_console_control *)(buf->buf + buf->offset); | |
1496 | ||
1497 | port = find_port_by_id(portdev, cpkt->id); | |
f909f850 | 1498 | if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) { |
17634ba2 AS |
1499 | /* No valid header at start of buffer. Drop it. */ |
1500 | dev_dbg(&portdev->vdev->dev, | |
1501 | "Invalid index %u in control packet\n", cpkt->id); | |
1502 | return; | |
1503 | } | |
1504 | ||
1505 | switch (cpkt->event) { | |
f909f850 AS |
1506 | case VIRTIO_CONSOLE_PORT_ADD: |
1507 | if (port) { | |
1d05160b AS |
1508 | dev_dbg(&portdev->vdev->dev, |
1509 | "Port %u already added\n", port->id); | |
f909f850 AS |
1510 | send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1); |
1511 | break; | |
1512 | } | |
1513 | if (cpkt->id >= portdev->config.max_nr_ports) { | |
1514 | dev_warn(&portdev->vdev->dev, | |
1515 | "Request for adding port with out-of-bound id %u, max. supported id: %u\n", | |
1516 | cpkt->id, portdev->config.max_nr_ports - 1); | |
1517 | break; | |
1518 | } | |
1519 | add_port(portdev, cpkt->id); | |
1520 | break; | |
1521 | case VIRTIO_CONSOLE_PORT_REMOVE: | |
b353a6b8 | 1522 | unplug_port(port); |
f909f850 | 1523 | break; |
17634ba2 AS |
1524 | case VIRTIO_CONSOLE_CONSOLE_PORT: |
1525 | if (!cpkt->value) | |
1526 | break; | |
1527 | if (is_console_port(port)) | |
1528 | break; | |
1529 | ||
1530 | init_port_console(port); | |
5e38483b | 1531 | complete(&early_console_added); |
17634ba2 AS |
1532 | /* |
1533 | * Could remove the port here in case init fails - but | |
1534 | * have to notify the host first. | |
1535 | */ | |
1536 | break; | |
8345adbf AS |
1537 | case VIRTIO_CONSOLE_RESIZE: { |
1538 | struct { | |
1539 | __u16 rows; | |
1540 | __u16 cols; | |
1541 | } size; | |
1542 | ||
17634ba2 AS |
1543 | if (!is_console_port(port)) |
1544 | break; | |
8345adbf AS |
1545 | |
1546 | memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt), | |
1547 | sizeof(size)); | |
1548 | set_console_size(port, size.rows, size.cols); | |
1549 | ||
17634ba2 AS |
1550 | port->cons.hvc->irq_requested = 1; |
1551 | resize_console(port); | |
1552 | break; | |
8345adbf | 1553 | } |
2030fa49 AS |
1554 | case VIRTIO_CONSOLE_PORT_OPEN: |
1555 | port->host_connected = cpkt->value; | |
1556 | wake_up_interruptible(&port->waitqueue); | |
cdfadfc1 AS |
1557 | /* |
1558 | * If the host port got closed and the host had any | |
1559 | * unconsumed buffers, we'll be able to reclaim them | |
1560 | * now. | |
1561 | */ | |
1562 | spin_lock_irq(&port->outvq_lock); | |
1563 | reclaim_consumed_buffers(port); | |
1564 | spin_unlock_irq(&port->outvq_lock); | |
3eae0ade AS |
1565 | |
1566 | /* | |
1567 | * If the guest is connected, it'll be interested in | |
1568 | * knowing the host connection state changed. | |
1569 | */ | |
1570 | send_sigio_to_port(port); | |
2030fa49 | 1571 | break; |
431edb8a | 1572 | case VIRTIO_CONSOLE_PORT_NAME: |
291024ef AS |
1573 | /* |
1574 | * If we woke up after hibernation, we can get this | |
1575 | * again. Skip it in that case. | |
1576 | */ | |
1577 | if (port->name) | |
1578 | break; | |
1579 | ||
431edb8a AS |
1580 | /* |
1581 | * Skip the size of the header and the cpkt to get the size | |
1582 | * of the name that was sent | |
1583 | */ | |
1584 | name_size = buf->len - buf->offset - sizeof(*cpkt) + 1; | |
1585 | ||
1586 | port->name = kmalloc(name_size, GFP_KERNEL); | |
1587 | if (!port->name) { | |
1588 | dev_err(port->dev, | |
1589 | "Not enough space to store port name\n"); | |
1590 | break; | |
1591 | } | |
1592 | strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt), | |
1593 | name_size - 1); | |
1594 | port->name[name_size - 1] = 0; | |
1595 | ||
1596 | /* | |
1597 | * Since we only have one sysfs attribute, 'name', | |
1598 | * create it only if we have a name for the port. | |
1599 | */ | |
1600 | err = sysfs_create_group(&port->dev->kobj, | |
1601 | &port_attribute_group); | |
ec64213c | 1602 | if (err) { |
431edb8a AS |
1603 | dev_err(port->dev, |
1604 | "Error %d creating sysfs device attributes\n", | |
1605 | err); | |
ec64213c AS |
1606 | } else { |
1607 | /* | |
1608 | * Generate a udev event so that appropriate | |
1609 | * symlinks can be created based on udev | |
1610 | * rules. | |
1611 | */ | |
1612 | kobject_uevent(&port->dev->kobj, KOBJ_CHANGE); | |
1613 | } | |
431edb8a | 1614 | break; |
17634ba2 AS |
1615 | } |
1616 | } | |
1617 | ||
1618 | static void control_work_handler(struct work_struct *work) | |
1619 | { | |
1620 | struct ports_device *portdev; | |
1621 | struct virtqueue *vq; | |
1622 | struct port_buffer *buf; | |
1623 | unsigned int len; | |
1624 | ||
1625 | portdev = container_of(work, struct ports_device, control_work); | |
1626 | vq = portdev->c_ivq; | |
1627 | ||
1628 | spin_lock(&portdev->cvq_lock); | |
505b0451 | 1629 | while ((buf = virtqueue_get_buf(vq, &len))) { |
17634ba2 AS |
1630 | spin_unlock(&portdev->cvq_lock); |
1631 | ||
1632 | buf->len = len; | |
1633 | buf->offset = 0; | |
1634 | ||
1635 | handle_control_message(portdev, buf); | |
1636 | ||
1637 | spin_lock(&portdev->cvq_lock); | |
1638 | if (add_inbuf(portdev->c_ivq, buf) < 0) { | |
1639 | dev_warn(&portdev->vdev->dev, | |
1640 | "Error adding buffer to queue\n"); | |
1641 | free_buf(buf); | |
1642 | } | |
1643 | } | |
1644 | spin_unlock(&portdev->cvq_lock); | |
1645 | } | |
1646 | ||
2770c5ea AS |
1647 | static void out_intr(struct virtqueue *vq) |
1648 | { | |
1649 | struct port *port; | |
1650 | ||
1651 | port = find_port_by_vq(vq->vdev->priv, vq); | |
1652 | if (!port) | |
1653 | return; | |
1654 | ||
1655 | wake_up_interruptible(&port->waitqueue); | |
1656 | } | |
1657 | ||
17634ba2 AS |
1658 | static void in_intr(struct virtqueue *vq) |
1659 | { | |
1660 | struct port *port; | |
1661 | unsigned long flags; | |
1662 | ||
1663 | port = find_port_by_vq(vq->vdev->priv, vq); | |
1664 | if (!port) | |
1665 | return; | |
1666 | ||
1667 | spin_lock_irqsave(&port->inbuf_lock, flags); | |
d25a9dda | 1668 | port->inbuf = get_inbuf(port); |
17634ba2 | 1669 | |
88f251ac AS |
1670 | /* |
1671 | * Don't queue up data when port is closed. This condition | |
1672 | * can be reached when a console port is not yet connected (no | |
1673 | * tty is spawned) and the host sends out data to console | |
1674 | * ports. For generic serial ports, the host won't | |
1675 | * (shouldn't) send data till the guest is connected. | |
1676 | */ | |
1677 | if (!port->guest_connected) | |
1678 | discard_port_data(port); | |
1679 | ||
17634ba2 AS |
1680 | spin_unlock_irqrestore(&port->inbuf_lock, flags); |
1681 | ||
2030fa49 AS |
1682 | wake_up_interruptible(&port->waitqueue); |
1683 | ||
55f6bcce AS |
1684 | /* Send a SIGIO indicating new data in case the process asked for it */ |
1685 | send_sigio_to_port(port); | |
1686 | ||
17634ba2 AS |
1687 | if (is_console_port(port) && hvc_poll(port->cons.hvc)) |
1688 | hvc_kick(); | |
1689 | } | |
1690 | ||
1691 | static void control_intr(struct virtqueue *vq) | |
1692 | { | |
1693 | struct ports_device *portdev; | |
1694 | ||
1695 | portdev = vq->vdev->priv; | |
1696 | schedule_work(&portdev->control_work); | |
1697 | } | |
1698 | ||
7f5d810d AS |
1699 | static void config_intr(struct virtio_device *vdev) |
1700 | { | |
1701 | struct ports_device *portdev; | |
1702 | ||
1703 | portdev = vdev->priv; | |
99f905f8 | 1704 | |
4038f5b7 | 1705 | if (!use_multiport(portdev)) { |
9778829c AS |
1706 | struct port *port; |
1707 | u16 rows, cols; | |
1708 | ||
1709 | vdev->config->get(vdev, | |
1710 | offsetof(struct virtio_console_config, cols), | |
1711 | &cols, sizeof(u16)); | |
1712 | vdev->config->get(vdev, | |
1713 | offsetof(struct virtio_console_config, rows), | |
1714 | &rows, sizeof(u16)); | |
1715 | ||
1716 | port = find_port_by_id(portdev, 0); | |
1717 | set_console_size(port, rows, cols); | |
1718 | ||
4038f5b7 AS |
1719 | /* |
1720 | * We'll use this way of resizing only for legacy | |
1721 | * support. For newer userspace | |
1722 | * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages | |
1723 | * to indicate console size changes so that it can be | |
1724 | * done per-port. | |
1725 | */ | |
9778829c | 1726 | resize_console(port); |
4038f5b7 | 1727 | } |
7f5d810d AS |
1728 | } |
1729 | ||
2658a79a AS |
1730 | static int init_vqs(struct ports_device *portdev) |
1731 | { | |
1732 | vq_callback_t **io_callbacks; | |
1733 | char **io_names; | |
1734 | struct virtqueue **vqs; | |
17634ba2 | 1735 | u32 i, j, nr_ports, nr_queues; |
2658a79a AS |
1736 | int err; |
1737 | ||
17634ba2 AS |
1738 | nr_ports = portdev->config.max_nr_ports; |
1739 | nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2; | |
2658a79a AS |
1740 | |
1741 | vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL); | |
2658a79a | 1742 | io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL); |
2658a79a | 1743 | io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL); |
2658a79a AS |
1744 | portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *), |
1745 | GFP_KERNEL); | |
2658a79a AS |
1746 | portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *), |
1747 | GFP_KERNEL); | |
22e132ff | 1748 | if (!vqs || !io_callbacks || !io_names || !portdev->in_vqs || |
286f9a22 | 1749 | !portdev->out_vqs) { |
2658a79a | 1750 | err = -ENOMEM; |
22e132ff | 1751 | goto free; |
2658a79a AS |
1752 | } |
1753 | ||
17634ba2 AS |
1754 | /* |
1755 | * For backward compat (newer host but older guest), the host | |
1756 | * spawns a console port first and also inits the vqs for port | |
1757 | * 0 before others. | |
1758 | */ | |
1759 | j = 0; | |
1760 | io_callbacks[j] = in_intr; | |
2770c5ea | 1761 | io_callbacks[j + 1] = out_intr; |
17634ba2 AS |
1762 | io_names[j] = "input"; |
1763 | io_names[j + 1] = "output"; | |
1764 | j += 2; | |
1765 | ||
1766 | if (use_multiport(portdev)) { | |
1767 | io_callbacks[j] = control_intr; | |
1768 | io_callbacks[j + 1] = NULL; | |
1769 | io_names[j] = "control-i"; | |
1770 | io_names[j + 1] = "control-o"; | |
1771 | ||
1772 | for (i = 1; i < nr_ports; i++) { | |
1773 | j += 2; | |
1774 | io_callbacks[j] = in_intr; | |
2770c5ea | 1775 | io_callbacks[j + 1] = out_intr; |
17634ba2 AS |
1776 | io_names[j] = "input"; |
1777 | io_names[j + 1] = "output"; | |
1778 | } | |
1779 | } | |
2658a79a AS |
1780 | /* Find the queues. */ |
1781 | err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs, | |
1782 | io_callbacks, | |
1783 | (const char **)io_names); | |
1784 | if (err) | |
22e132ff | 1785 | goto free; |
2658a79a | 1786 | |
17634ba2 | 1787 | j = 0; |
2658a79a AS |
1788 | portdev->in_vqs[0] = vqs[0]; |
1789 | portdev->out_vqs[0] = vqs[1]; | |
17634ba2 AS |
1790 | j += 2; |
1791 | if (use_multiport(portdev)) { | |
1792 | portdev->c_ivq = vqs[j]; | |
1793 | portdev->c_ovq = vqs[j + 1]; | |
1794 | ||
1795 | for (i = 1; i < nr_ports; i++) { | |
1796 | j += 2; | |
1797 | portdev->in_vqs[i] = vqs[j]; | |
1798 | portdev->out_vqs[i] = vqs[j + 1]; | |
1799 | } | |
1800 | } | |
2658a79a | 1801 | kfree(io_names); |
22e132ff | 1802 | kfree(io_callbacks); |
2658a79a AS |
1803 | kfree(vqs); |
1804 | ||
1805 | return 0; | |
1806 | ||
22e132ff | 1807 | free: |
2658a79a | 1808 | kfree(portdev->out_vqs); |
2658a79a | 1809 | kfree(portdev->in_vqs); |
22e132ff JS |
1810 | kfree(io_names); |
1811 | kfree(io_callbacks); | |
2658a79a | 1812 | kfree(vqs); |
22e132ff | 1813 | |
2658a79a AS |
1814 | return err; |
1815 | } | |
1816 | ||
fb08bd27 AS |
1817 | static const struct file_operations portdev_fops = { |
1818 | .owner = THIS_MODULE, | |
1819 | }; | |
1820 | ||
a0e2dbfc AS |
1821 | static void remove_vqs(struct ports_device *portdev) |
1822 | { | |
1823 | portdev->vdev->config->del_vqs(portdev->vdev); | |
1824 | kfree(portdev->in_vqs); | |
1825 | kfree(portdev->out_vqs); | |
1826 | } | |
1827 | ||
1828 | static void remove_controlq_data(struct ports_device *portdev) | |
1829 | { | |
1830 | struct port_buffer *buf; | |
1831 | unsigned int len; | |
1832 | ||
1833 | if (!use_multiport(portdev)) | |
1834 | return; | |
1835 | ||
1836 | while ((buf = virtqueue_get_buf(portdev->c_ivq, &len))) | |
1837 | free_buf(buf); | |
1838 | ||
1839 | while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq))) | |
1840 | free_buf(buf); | |
1841 | } | |
1842 | ||
1c85bf35 AS |
1843 | /* |
1844 | * Once we're further in boot, we get probed like any other virtio | |
1845 | * device. | |
17634ba2 AS |
1846 | * |
1847 | * If the host also supports multiple console ports, we check the | |
1848 | * config space to see how many ports the host has spawned. We | |
1849 | * initialize each port found. | |
1c85bf35 AS |
1850 | */ |
1851 | static int __devinit virtcons_probe(struct virtio_device *vdev) | |
1852 | { | |
1c85bf35 AS |
1853 | struct ports_device *portdev; |
1854 | int err; | |
17634ba2 | 1855 | bool multiport; |
5e38483b CB |
1856 | bool early = early_put_chars != NULL; |
1857 | ||
1858 | /* Ensure to read early_put_chars now */ | |
1859 | barrier(); | |
1c85bf35 AS |
1860 | |
1861 | portdev = kmalloc(sizeof(*portdev), GFP_KERNEL); | |
1862 | if (!portdev) { | |
1863 | err = -ENOMEM; | |
1864 | goto fail; | |
1865 | } | |
1866 | ||
1867 | /* Attach this portdev to this virtio_device, and vice-versa. */ | |
1868 | portdev->vdev = vdev; | |
1869 | vdev->priv = portdev; | |
1870 | ||
fb08bd27 AS |
1871 | spin_lock_irq(&pdrvdata_lock); |
1872 | portdev->drv_index = pdrvdata.index++; | |
1873 | spin_unlock_irq(&pdrvdata_lock); | |
1874 | ||
1875 | portdev->chr_major = register_chrdev(0, "virtio-portsdev", | |
1876 | &portdev_fops); | |
1877 | if (portdev->chr_major < 0) { | |
1878 | dev_err(&vdev->dev, | |
1879 | "Error %d registering chrdev for device %u\n", | |
1880 | portdev->chr_major, portdev->drv_index); | |
1881 | err = portdev->chr_major; | |
1882 | goto free; | |
1883 | } | |
1884 | ||
17634ba2 | 1885 | multiport = false; |
17634ba2 | 1886 | portdev->config.max_nr_ports = 1; |
51c6d61a SL |
1887 | if (virtio_config_val(vdev, VIRTIO_CONSOLE_F_MULTIPORT, |
1888 | offsetof(struct virtio_console_config, | |
1889 | max_nr_ports), | |
1890 | &portdev->config.max_nr_ports) == 0) | |
17634ba2 | 1891 | multiport = true; |
17634ba2 | 1892 | |
2658a79a AS |
1893 | err = init_vqs(portdev); |
1894 | if (err < 0) { | |
1895 | dev_err(&vdev->dev, "Error %d initializing vqs\n", err); | |
fb08bd27 | 1896 | goto free_chrdev; |
2658a79a | 1897 | } |
1c85bf35 | 1898 | |
17634ba2 AS |
1899 | spin_lock_init(&portdev->ports_lock); |
1900 | INIT_LIST_HEAD(&portdev->ports); | |
1901 | ||
1902 | if (multiport) { | |
335a64a5 AS |
1903 | unsigned int nr_added_bufs; |
1904 | ||
17634ba2 AS |
1905 | spin_lock_init(&portdev->cvq_lock); |
1906 | INIT_WORK(&portdev->control_work, &control_work_handler); | |
1907 | ||
335a64a5 AS |
1908 | nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock); |
1909 | if (!nr_added_bufs) { | |
22a29eac AS |
1910 | dev_err(&vdev->dev, |
1911 | "Error allocating buffers for control queue\n"); | |
1912 | err = -ENOMEM; | |
1913 | goto free_vqs; | |
1914 | } | |
1d05160b AS |
1915 | } else { |
1916 | /* | |
1917 | * For backward compatibility: Create a console port | |
1918 | * if we're running on older host. | |
1919 | */ | |
1920 | add_port(portdev, 0); | |
17634ba2 AS |
1921 | } |
1922 | ||
6bdf2afd AS |
1923 | spin_lock_irq(&pdrvdata_lock); |
1924 | list_add_tail(&portdev->list, &pdrvdata.portdevs); | |
1925 | spin_unlock_irq(&pdrvdata_lock); | |
1926 | ||
f909f850 AS |
1927 | __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID, |
1928 | VIRTIO_CONSOLE_DEVICE_READY, 1); | |
5e38483b CB |
1929 | |
1930 | /* | |
1931 | * If there was an early virtio console, assume that there are no | |
1932 | * other consoles. We need to wait until the hvc_alloc matches the | |
1933 | * hvc_instantiate, otherwise tty_open will complain, resulting in | |
1934 | * a "Warning: unable to open an initial console" boot failure. | |
1935 | * Without multiport this is done in add_port above. With multiport | |
1936 | * this might take some host<->guest communication - thus we have to | |
1937 | * wait. | |
1938 | */ | |
1939 | if (multiport && early) | |
1940 | wait_for_completion(&early_console_added); | |
1941 | ||
31610434 RR |
1942 | return 0; |
1943 | ||
22a29eac | 1944 | free_vqs: |
0643e4c6 JL |
1945 | /* The host might want to notify mgmt sw about device add failure */ |
1946 | __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID, | |
1947 | VIRTIO_CONSOLE_DEVICE_READY, 0); | |
a0e2dbfc | 1948 | remove_vqs(portdev); |
fb08bd27 AS |
1949 | free_chrdev: |
1950 | unregister_chrdev(portdev->chr_major, "virtio-portsdev"); | |
31610434 | 1951 | free: |
1c85bf35 | 1952 | kfree(portdev); |
31610434 RR |
1953 | fail: |
1954 | return err; | |
1955 | } | |
1956 | ||
7177876f AS |
1957 | static void virtcons_remove(struct virtio_device *vdev) |
1958 | { | |
1959 | struct ports_device *portdev; | |
1960 | struct port *port, *port2; | |
7177876f AS |
1961 | |
1962 | portdev = vdev->priv; | |
1963 | ||
6bdf2afd AS |
1964 | spin_lock_irq(&pdrvdata_lock); |
1965 | list_del(&portdev->list); | |
1966 | spin_unlock_irq(&pdrvdata_lock); | |
1967 | ||
02238959 AS |
1968 | /* Disable interrupts for vqs */ |
1969 | vdev->config->reset(vdev); | |
1970 | /* Finish up work that's lined up */ | |
7177876f | 1971 | cancel_work_sync(&portdev->control_work); |
7177876f AS |
1972 | |
1973 | list_for_each_entry_safe(port, port2, &portdev->ports, list) | |
b353a6b8 | 1974 | unplug_port(port); |
7177876f AS |
1975 | |
1976 | unregister_chrdev(portdev->chr_major, "virtio-portsdev"); | |
1977 | ||
e062013c AS |
1978 | /* |
1979 | * When yanking out a device, we immediately lose the | |
1980 | * (device-side) queues. So there's no point in keeping the | |
1981 | * guest side around till we drop our final reference. This | |
1982 | * also means that any ports which are in an open state will | |
1983 | * have to just stop using the port, as the vqs are going | |
1984 | * away. | |
1985 | */ | |
a0e2dbfc AS |
1986 | remove_controlq_data(portdev); |
1987 | remove_vqs(portdev); | |
7177876f AS |
1988 | kfree(portdev); |
1989 | } | |
1990 | ||
31610434 RR |
1991 | static struct virtio_device_id id_table[] = { |
1992 | { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID }, | |
1993 | { 0 }, | |
1994 | }; | |
1995 | ||
c2983458 CB |
1996 | static unsigned int features[] = { |
1997 | VIRTIO_CONSOLE_F_SIZE, | |
b99fa815 | 1998 | VIRTIO_CONSOLE_F_MULTIPORT, |
c2983458 CB |
1999 | }; |
2000 | ||
2b8f41d8 AS |
2001 | #ifdef CONFIG_PM |
2002 | static int virtcons_freeze(struct virtio_device *vdev) | |
2003 | { | |
2004 | struct ports_device *portdev; | |
2005 | struct port *port; | |
2006 | ||
2007 | portdev = vdev->priv; | |
2008 | ||
2009 | vdev->config->reset(vdev); | |
2010 | ||
c743d09d | 2011 | virtqueue_disable_cb(portdev->c_ivq); |
2b8f41d8 | 2012 | cancel_work_sync(&portdev->control_work); |
c743d09d AS |
2013 | /* |
2014 | * Once more: if control_work_handler() was running, it would | |
2015 | * enable the cb as the last step. | |
2016 | */ | |
2017 | virtqueue_disable_cb(portdev->c_ivq); | |
2b8f41d8 AS |
2018 | remove_controlq_data(portdev); |
2019 | ||
2020 | list_for_each_entry(port, &portdev->ports, list) { | |
c743d09d AS |
2021 | virtqueue_disable_cb(port->in_vq); |
2022 | virtqueue_disable_cb(port->out_vq); | |
2b8f41d8 AS |
2023 | /* |
2024 | * We'll ask the host later if the new invocation has | |
2025 | * the port opened or closed. | |
2026 | */ | |
2027 | port->host_connected = false; | |
2028 | remove_port_data(port); | |
2029 | } | |
2030 | remove_vqs(portdev); | |
2031 | ||
2032 | return 0; | |
2033 | } | |
2034 | ||
2035 | static int virtcons_restore(struct virtio_device *vdev) | |
2036 | { | |
2037 | struct ports_device *portdev; | |
2038 | struct port *port; | |
2039 | int ret; | |
2040 | ||
2041 | portdev = vdev->priv; | |
2042 | ||
2043 | ret = init_vqs(portdev); | |
2044 | if (ret) | |
2045 | return ret; | |
2046 | ||
2047 | if (use_multiport(portdev)) | |
2048 | fill_queue(portdev->c_ivq, &portdev->cvq_lock); | |
2049 | ||
2050 | list_for_each_entry(port, &portdev->ports, list) { | |
2051 | port->in_vq = portdev->in_vqs[port->id]; | |
2052 | port->out_vq = portdev->out_vqs[port->id]; | |
2053 | ||
2054 | fill_queue(port->in_vq, &port->inbuf_lock); | |
2055 | ||
2056 | /* Get port open/close status on the host */ | |
2057 | send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1); | |
fa8b66cc AS |
2058 | |
2059 | /* | |
2060 | * If a port was open at the time of suspending, we | |
2061 | * have to let the host know that it's still open. | |
2062 | */ | |
2063 | if (port->guest_connected) | |
2064 | send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1); | |
2b8f41d8 AS |
2065 | } |
2066 | return 0; | |
2067 | } | |
2068 | #endif | |
2069 | ||
31610434 | 2070 | static struct virtio_driver virtio_console = { |
c2983458 CB |
2071 | .feature_table = features, |
2072 | .feature_table_size = ARRAY_SIZE(features), | |
31610434 RR |
2073 | .driver.name = KBUILD_MODNAME, |
2074 | .driver.owner = THIS_MODULE, | |
2075 | .id_table = id_table, | |
2076 | .probe = virtcons_probe, | |
7177876f | 2077 | .remove = virtcons_remove, |
7f5d810d | 2078 | .config_changed = config_intr, |
2b8f41d8 AS |
2079 | #ifdef CONFIG_PM |
2080 | .freeze = virtcons_freeze, | |
2081 | .restore = virtcons_restore, | |
2082 | #endif | |
31610434 RR |
2083 | }; |
2084 | ||
2085 | static int __init init(void) | |
2086 | { | |
fb08bd27 AS |
2087 | int err; |
2088 | ||
2089 | pdrvdata.class = class_create(THIS_MODULE, "virtio-ports"); | |
2090 | if (IS_ERR(pdrvdata.class)) { | |
2091 | err = PTR_ERR(pdrvdata.class); | |
2092 | pr_err("Error %d creating virtio-ports class\n", err); | |
2093 | return err; | |
2094 | } | |
d99393ef AS |
2095 | |
2096 | pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL); | |
2097 | if (!pdrvdata.debugfs_dir) { | |
2098 | pr_warning("Error %ld creating debugfs dir for virtio-ports\n", | |
2099 | PTR_ERR(pdrvdata.debugfs_dir)); | |
2100 | } | |
38edf58d | 2101 | INIT_LIST_HEAD(&pdrvdata.consoles); |
6bdf2afd | 2102 | INIT_LIST_HEAD(&pdrvdata.portdevs); |
38edf58d | 2103 | |
33e1afc3 AK |
2104 | err = register_virtio_driver(&virtio_console); |
2105 | if (err < 0) { | |
2106 | pr_err("Error %d registering virtio driver\n", err); | |
2107 | goto free; | |
2108 | } | |
2109 | return 0; | |
2110 | free: | |
2111 | if (pdrvdata.debugfs_dir) | |
2112 | debugfs_remove_recursive(pdrvdata.debugfs_dir); | |
2113 | class_destroy(pdrvdata.class); | |
2114 | return err; | |
31610434 | 2115 | } |
7177876f AS |
2116 | |
2117 | static void __exit fini(void) | |
2118 | { | |
2119 | unregister_virtio_driver(&virtio_console); | |
2120 | ||
2121 | class_destroy(pdrvdata.class); | |
2122 | if (pdrvdata.debugfs_dir) | |
2123 | debugfs_remove_recursive(pdrvdata.debugfs_dir); | |
2124 | } | |
31610434 | 2125 | module_init(init); |
7177876f | 2126 | module_exit(fini); |
31610434 RR |
2127 | |
2128 | MODULE_DEVICE_TABLE(virtio, id_table); | |
2129 | MODULE_DESCRIPTION("Virtio console driver"); | |
2130 | MODULE_LICENSE("GPL"); |