Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 | 2 | /* |
62b74942 | 3 | * SCLP VT220 terminal driver. |
1da177e4 | 4 | * |
62b74942 MH |
5 | * Copyright IBM Corp. 2003, 2009 |
6 | * | |
7 | * Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com> | |
1da177e4 LT |
8 | */ |
9 | ||
1da177e4 LT |
10 | #include <linux/module.h> |
11 | #include <linux/spinlock.h> | |
12 | #include <linux/list.h> | |
13 | #include <linux/wait.h> | |
14 | #include <linux/timer.h> | |
15 | #include <linux/kernel.h> | |
1d3f9094 | 16 | #include <linux/sysrq.h> |
1da177e4 LT |
17 | #include <linux/tty.h> |
18 | #include <linux/tty_driver.h> | |
33f0f88f | 19 | #include <linux/tty_flip.h> |
1da177e4 LT |
20 | #include <linux/errno.h> |
21 | #include <linux/mm.h> | |
22 | #include <linux/major.h> | |
23 | #include <linux/console.h> | |
24 | #include <linux/kdev_t.h> | |
1da177e4 LT |
25 | #include <linux/interrupt.h> |
26 | #include <linux/init.h> | |
2332ce1a | 27 | #include <linux/reboot.h> |
5a0e3ad6 | 28 | #include <linux/slab.h> |
2332ce1a | 29 | |
7c0f6ba6 | 30 | #include <linux/uaccess.h> |
1da177e4 | 31 | #include "sclp.h" |
1d3f9094 | 32 | #include "ctrlchar.h" |
1da177e4 | 33 | |
1da177e4 LT |
34 | #define SCLP_VT220_MAJOR TTY_MAJOR |
35 | #define SCLP_VT220_MINOR 65 | |
36 | #define SCLP_VT220_DRIVER_NAME "sclp_vt220" | |
37 | #define SCLP_VT220_DEVICE_NAME "ttysclp" | |
38 | #define SCLP_VT220_CONSOLE_NAME "ttyS" | |
39 | #define SCLP_VT220_CONSOLE_INDEX 1 /* console=ttyS1 */ | |
1da177e4 LT |
40 | |
41 | /* Representation of a single write request */ | |
42 | struct sclp_vt220_request { | |
43 | struct list_head list; | |
44 | struct sclp_req sclp_req; | |
45 | int retry_count; | |
46 | }; | |
47 | ||
48 | /* VT220 SCCB */ | |
49 | struct sclp_vt220_sccb { | |
50 | struct sccb_header header; | |
51 | struct evbuf_header evbuf; | |
52 | }; | |
53 | ||
54 | #define SCLP_VT220_MAX_CHARS_PER_BUFFER (PAGE_SIZE - \ | |
55 | sizeof(struct sclp_vt220_request) - \ | |
56 | sizeof(struct sclp_vt220_sccb)) | |
57 | ||
58 | /* Structures and data needed to register tty driver */ | |
59 | static struct tty_driver *sclp_vt220_driver; | |
60 | ||
092f7377 | 61 | static struct tty_port sclp_vt220_port; |
1da177e4 LT |
62 | |
63 | /* Lock to protect internal data from concurrent access */ | |
64 | static spinlock_t sclp_vt220_lock; | |
65 | ||
66 | /* List of empty pages to be used as write request buffers */ | |
67 | static struct list_head sclp_vt220_empty; | |
68 | ||
69 | /* List of pending requests */ | |
70 | static struct list_head sclp_vt220_outqueue; | |
71 | ||
62b74942 MH |
72 | /* Suspend mode flag */ |
73 | static int sclp_vt220_suspended; | |
74 | ||
75 | /* Flag that output queue is currently running */ | |
76 | static int sclp_vt220_queue_running; | |
1da177e4 | 77 | |
1da177e4 LT |
78 | /* Timer used for delaying write requests to merge subsequent messages into |
79 | * a single buffer */ | |
80 | static struct timer_list sclp_vt220_timer; | |
81 | ||
82 | /* Pointer to current request buffer which has been partially filled but not | |
83 | * yet sent */ | |
84 | static struct sclp_vt220_request *sclp_vt220_current_request; | |
85 | ||
86 | /* Number of characters in current request buffer */ | |
87 | static int sclp_vt220_buffered_chars; | |
88 | ||
ad211790 PO |
89 | /* Counter controlling core driver initialization. */ |
90 | static int __initdata sclp_vt220_init_count; | |
1da177e4 LT |
91 | |
92 | /* Flag indicating that sclp_vt220_current_request should really | |
93 | * have been already queued but wasn't because the SCLP was processing | |
94 | * another buffer */ | |
95 | static int sclp_vt220_flush_later; | |
96 | ||
97 | static void sclp_vt220_receiver_fn(struct evbuf_header *evbuf); | |
62b74942 MH |
98 | static void sclp_vt220_pm_event_fn(struct sclp_register *reg, |
99 | enum sclp_pm_event sclp_pm_event); | |
1da177e4 LT |
100 | static int __sclp_vt220_emit(struct sclp_vt220_request *request); |
101 | static void sclp_vt220_emit_current(void); | |
102 | ||
e106e4ea | 103 | /* Registration structure for SCLP output event buffers */ |
1da177e4 | 104 | static struct sclp_register sclp_vt220_register = { |
6d4740c8 | 105 | .send_mask = EVTYP_VT220MSG_MASK, |
e106e4ea PO |
106 | .pm_event_fn = sclp_vt220_pm_event_fn, |
107 | }; | |
108 | ||
109 | /* Registration structure for SCLP input event buffers */ | |
110 | static struct sclp_register sclp_vt220_register_input = { | |
6d4740c8 | 111 | .receive_mask = EVTYP_VT220MSG_MASK, |
62b74942 | 112 | .receiver_fn = sclp_vt220_receiver_fn, |
1da177e4 LT |
113 | }; |
114 | ||
115 | ||
116 | /* | |
117 | * Put provided request buffer back into queue and check emit pending | |
118 | * buffers if necessary. | |
119 | */ | |
120 | static void | |
121 | sclp_vt220_process_queue(struct sclp_vt220_request *request) | |
122 | { | |
123 | unsigned long flags; | |
124 | void *page; | |
125 | ||
126 | do { | |
127 | /* Put buffer back to list of empty buffers */ | |
128 | page = request->sclp_req.sccb; | |
129 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
130 | /* Move request from outqueue to empty queue */ | |
131 | list_del(&request->list); | |
1da177e4 LT |
132 | list_add_tail((struct list_head *) page, &sclp_vt220_empty); |
133 | /* Check if there is a pending buffer on the out queue. */ | |
134 | request = NULL; | |
135 | if (!list_empty(&sclp_vt220_outqueue)) | |
136 | request = list_entry(sclp_vt220_outqueue.next, | |
137 | struct sclp_vt220_request, list); | |
62b74942 MH |
138 | if (!request || sclp_vt220_suspended) { |
139 | sclp_vt220_queue_running = 0; | |
140 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
141 | break; | |
142 | } | |
1da177e4 | 143 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
62b74942 | 144 | } while (__sclp_vt220_emit(request)); |
1da177e4 LT |
145 | if (request == NULL && sclp_vt220_flush_later) |
146 | sclp_vt220_emit_current(); | |
6aad04f2 | 147 | tty_port_tty_wakeup(&sclp_vt220_port); |
1da177e4 LT |
148 | } |
149 | ||
150 | #define SCLP_BUFFER_MAX_RETRY 1 | |
151 | ||
152 | /* | |
153 | * Callback through which the result of a write request is reported by the | |
154 | * SCLP. | |
155 | */ | |
156 | static void | |
157 | sclp_vt220_callback(struct sclp_req *request, void *data) | |
158 | { | |
159 | struct sclp_vt220_request *vt220_request; | |
160 | struct sclp_vt220_sccb *sccb; | |
161 | ||
162 | vt220_request = (struct sclp_vt220_request *) data; | |
163 | if (request->status == SCLP_REQ_FAILED) { | |
164 | sclp_vt220_process_queue(vt220_request); | |
165 | return; | |
166 | } | |
167 | sccb = (struct sclp_vt220_sccb *) vt220_request->sclp_req.sccb; | |
168 | ||
169 | /* Check SCLP response code and choose suitable action */ | |
170 | switch (sccb->header.response_code) { | |
171 | case 0x0020 : | |
172 | break; | |
173 | ||
174 | case 0x05f0: /* Target resource in improper state */ | |
175 | break; | |
176 | ||
177 | case 0x0340: /* Contained SCLP equipment check */ | |
178 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) | |
179 | break; | |
180 | /* Remove processed buffers and requeue rest */ | |
181 | if (sclp_remove_processed((struct sccb_header *) sccb) > 0) { | |
182 | /* Not all buffers were processed */ | |
183 | sccb->header.response_code = 0x0000; | |
184 | vt220_request->sclp_req.status = SCLP_REQ_FILLED; | |
185 | if (sclp_add_request(request) == 0) | |
186 | return; | |
187 | } | |
188 | break; | |
189 | ||
190 | case 0x0040: /* SCLP equipment check */ | |
191 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) | |
192 | break; | |
193 | sccb->header.response_code = 0x0000; | |
194 | vt220_request->sclp_req.status = SCLP_REQ_FILLED; | |
195 | if (sclp_add_request(request) == 0) | |
196 | return; | |
197 | break; | |
198 | ||
199 | default: | |
200 | break; | |
201 | } | |
202 | sclp_vt220_process_queue(vt220_request); | |
203 | } | |
204 | ||
205 | /* | |
206 | * Emit vt220 request buffer to SCLP. Return zero on success, non-zero | |
207 | * otherwise. | |
208 | */ | |
209 | static int | |
210 | __sclp_vt220_emit(struct sclp_vt220_request *request) | |
211 | { | |
ab14de6c | 212 | request->sclp_req.command = SCLP_CMDW_WRITE_EVENT_DATA; |
1da177e4 LT |
213 | request->sclp_req.status = SCLP_REQ_FILLED; |
214 | request->sclp_req.callback = sclp_vt220_callback; | |
215 | request->sclp_req.callback_data = (void *) request; | |
216 | ||
217 | return sclp_add_request(&request->sclp_req); | |
218 | } | |
219 | ||
220 | /* | |
62b74942 | 221 | * Queue and emit current request. |
1da177e4 LT |
222 | */ |
223 | static void | |
224 | sclp_vt220_emit_current(void) | |
225 | { | |
226 | unsigned long flags; | |
227 | struct sclp_vt220_request *request; | |
228 | struct sclp_vt220_sccb *sccb; | |
229 | ||
230 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
62b74942 | 231 | if (sclp_vt220_current_request) { |
1da177e4 LT |
232 | sccb = (struct sclp_vt220_sccb *) |
233 | sclp_vt220_current_request->sclp_req.sccb; | |
234 | /* Only emit buffers with content */ | |
235 | if (sccb->header.length != sizeof(struct sclp_vt220_sccb)) { | |
62b74942 MH |
236 | list_add_tail(&sclp_vt220_current_request->list, |
237 | &sclp_vt220_outqueue); | |
1da177e4 LT |
238 | sclp_vt220_current_request = NULL; |
239 | if (timer_pending(&sclp_vt220_timer)) | |
240 | del_timer(&sclp_vt220_timer); | |
241 | } | |
242 | sclp_vt220_flush_later = 0; | |
243 | } | |
62b74942 MH |
244 | if (sclp_vt220_queue_running || sclp_vt220_suspended) |
245 | goto out_unlock; | |
246 | if (list_empty(&sclp_vt220_outqueue)) | |
247 | goto out_unlock; | |
248 | request = list_first_entry(&sclp_vt220_outqueue, | |
249 | struct sclp_vt220_request, list); | |
250 | sclp_vt220_queue_running = 1; | |
251 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
252 | ||
253 | if (__sclp_vt220_emit(request)) | |
254 | sclp_vt220_process_queue(request); | |
255 | return; | |
256 | out_unlock: | |
1da177e4 | 257 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
1da177e4 LT |
258 | } |
259 | ||
260 | #define SCLP_NORMAL_WRITE 0x00 | |
261 | ||
262 | /* | |
263 | * Helper function to initialize a page with the sclp request structure. | |
264 | */ | |
265 | static struct sclp_vt220_request * | |
266 | sclp_vt220_initialize_page(void *page) | |
267 | { | |
268 | struct sclp_vt220_request *request; | |
269 | struct sclp_vt220_sccb *sccb; | |
270 | ||
271 | /* Place request structure at end of page */ | |
272 | request = ((struct sclp_vt220_request *) | |
273 | ((addr_t) page + PAGE_SIZE)) - 1; | |
274 | request->retry_count = 0; | |
275 | request->sclp_req.sccb = page; | |
276 | /* SCCB goes at start of page */ | |
277 | sccb = (struct sclp_vt220_sccb *) page; | |
278 | memset((void *) sccb, 0, sizeof(struct sclp_vt220_sccb)); | |
279 | sccb->header.length = sizeof(struct sclp_vt220_sccb); | |
280 | sccb->header.function_code = SCLP_NORMAL_WRITE; | |
281 | sccb->header.response_code = 0x0000; | |
6d4740c8 | 282 | sccb->evbuf.type = EVTYP_VT220MSG; |
1da177e4 LT |
283 | sccb->evbuf.length = sizeof(struct evbuf_header); |
284 | ||
285 | return request; | |
286 | } | |
287 | ||
288 | static inline unsigned int | |
289 | sclp_vt220_space_left(struct sclp_vt220_request *request) | |
290 | { | |
291 | struct sclp_vt220_sccb *sccb; | |
292 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
293 | return PAGE_SIZE - sizeof(struct sclp_vt220_request) - | |
294 | sccb->header.length; | |
295 | } | |
296 | ||
297 | static inline unsigned int | |
298 | sclp_vt220_chars_stored(struct sclp_vt220_request *request) | |
299 | { | |
300 | struct sclp_vt220_sccb *sccb; | |
301 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
302 | return sccb->evbuf.length - sizeof(struct evbuf_header); | |
303 | } | |
304 | ||
305 | /* | |
306 | * Add msg to buffer associated with request. Return the number of characters | |
307 | * added. | |
308 | */ | |
309 | static int | |
310 | sclp_vt220_add_msg(struct sclp_vt220_request *request, | |
311 | const unsigned char *msg, int count, int convertlf) | |
312 | { | |
313 | struct sclp_vt220_sccb *sccb; | |
314 | void *buffer; | |
315 | unsigned char c; | |
316 | int from; | |
317 | int to; | |
318 | ||
319 | if (count > sclp_vt220_space_left(request)) | |
320 | count = sclp_vt220_space_left(request); | |
321 | if (count <= 0) | |
322 | return 0; | |
323 | ||
324 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
325 | buffer = (void *) ((addr_t) sccb + sccb->header.length); | |
326 | ||
327 | if (convertlf) { | |
328 | /* Perform Linefeed conversion (0x0a -> 0x0a 0x0d)*/ | |
329 | for (from=0, to=0; | |
330 | (from < count) && (to < sclp_vt220_space_left(request)); | |
331 | from++) { | |
332 | /* Retrieve character */ | |
333 | c = msg[from]; | |
334 | /* Perform conversion */ | |
335 | if (c == 0x0a) { | |
336 | if (to + 1 < sclp_vt220_space_left(request)) { | |
337 | ((unsigned char *) buffer)[to++] = c; | |
338 | ((unsigned char *) buffer)[to++] = 0x0d; | |
339 | } else | |
340 | break; | |
341 | ||
342 | } else | |
343 | ((unsigned char *) buffer)[to++] = c; | |
344 | } | |
345 | sccb->header.length += to; | |
346 | sccb->evbuf.length += to; | |
347 | return from; | |
348 | } else { | |
349 | memcpy(buffer, (const void *) msg, count); | |
350 | sccb->header.length += count; | |
351 | sccb->evbuf.length += count; | |
352 | return count; | |
353 | } | |
354 | } | |
355 | ||
356 | /* | |
357 | * Emit buffer after having waited long enough for more data to arrive. | |
358 | */ | |
359 | static void | |
360 | sclp_vt220_timeout(unsigned long data) | |
361 | { | |
362 | sclp_vt220_emit_current(); | |
363 | } | |
364 | ||
fa331ffc | 365 | #define BUFFER_MAX_DELAY HZ/20 |
1da177e4 | 366 | |
25b41a7b MS |
367 | /* |
368 | * Drop oldest console buffer if sclp_con_drop is set | |
369 | */ | |
370 | static int | |
371 | sclp_vt220_drop_buffer(void) | |
372 | { | |
373 | struct list_head *list; | |
374 | struct sclp_vt220_request *request; | |
375 | void *page; | |
376 | ||
377 | if (!sclp_console_drop) | |
378 | return 0; | |
379 | list = sclp_vt220_outqueue.next; | |
380 | if (sclp_vt220_queue_running) | |
381 | /* The first element is in I/O */ | |
382 | list = list->next; | |
383 | if (list == &sclp_vt220_outqueue) | |
384 | return 0; | |
385 | list_del(list); | |
386 | request = list_entry(list, struct sclp_vt220_request, list); | |
387 | page = request->sclp_req.sccb; | |
388 | list_add_tail((struct list_head *) page, &sclp_vt220_empty); | |
389 | return 1; | |
390 | } | |
391 | ||
1da177e4 LT |
392 | /* |
393 | * Internal implementation of the write function. Write COUNT bytes of data | |
394 | * from memory at BUF | |
395 | * to the SCLP interface. In case that the data does not fit into the current | |
396 | * write buffer, emit the current one and allocate a new one. If there are no | |
397 | * more empty buffers available, wait until one gets emptied. If DO_SCHEDULE | |
398 | * is non-zero, the buffer will be scheduled for emitting after a timeout - | |
399 | * otherwise the user has to explicitly call the flush function. | |
400 | * A non-zero CONVERTLF parameter indicates that 0x0a characters in the message | |
401 | * buffer should be converted to 0x0a 0x0d. After completion, return the number | |
402 | * of bytes written. | |
403 | */ | |
404 | static int | |
405 | __sclp_vt220_write(const unsigned char *buf, int count, int do_schedule, | |
d4820e44 | 406 | int convertlf, int may_fail) |
1da177e4 LT |
407 | { |
408 | unsigned long flags; | |
409 | void *page; | |
410 | int written; | |
411 | int overall_written; | |
412 | ||
413 | if (count <= 0) | |
414 | return 0; | |
415 | overall_written = 0; | |
416 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
417 | do { | |
d4820e44 | 418 | /* Create an sclp output buffer if none exists yet */ |
1da177e4 | 419 | if (sclp_vt220_current_request == NULL) { |
25b41a7b MS |
420 | if (list_empty(&sclp_vt220_empty)) |
421 | sclp_console_full++; | |
1da177e4 | 422 | while (list_empty(&sclp_vt220_empty)) { |
62b74942 | 423 | if (may_fail || sclp_vt220_suspended) |
d4820e44 | 424 | goto out; |
25b41a7b MS |
425 | if (sclp_vt220_drop_buffer()) |
426 | break; | |
427 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
428 | ||
429 | sclp_sync_wait(); | |
1da177e4 LT |
430 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
431 | } | |
432 | page = (void *) sclp_vt220_empty.next; | |
433 | list_del((struct list_head *) page); | |
434 | sclp_vt220_current_request = | |
435 | sclp_vt220_initialize_page(page); | |
436 | } | |
437 | /* Try to write the string to the current request buffer */ | |
438 | written = sclp_vt220_add_msg(sclp_vt220_current_request, | |
439 | buf, count, convertlf); | |
440 | overall_written += written; | |
441 | if (written == count) | |
442 | break; | |
443 | /* | |
444 | * Not all characters could be written to the current | |
445 | * output buffer. Emit the buffer, create a new buffer | |
446 | * and then output the rest of the string. | |
447 | */ | |
448 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
449 | sclp_vt220_emit_current(); | |
450 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
451 | buf += written; | |
452 | count -= written; | |
453 | } while (count > 0); | |
454 | /* Setup timer to output current console buffer after some time */ | |
455 | if (sclp_vt220_current_request != NULL && | |
456 | !timer_pending(&sclp_vt220_timer) && do_schedule) { | |
457 | sclp_vt220_timer.function = sclp_vt220_timeout; | |
458 | sclp_vt220_timer.data = 0UL; | |
459 | sclp_vt220_timer.expires = jiffies + BUFFER_MAX_DELAY; | |
460 | add_timer(&sclp_vt220_timer); | |
461 | } | |
d4820e44 | 462 | out: |
25b41a7b | 463 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
1da177e4 LT |
464 | return overall_written; |
465 | } | |
466 | ||
467 | /* | |
468 | * This routine is called by the kernel to write a series of | |
469 | * characters to the tty device. The characters may come from | |
470 | * user space or kernel space. This routine will return the | |
471 | * number of characters actually accepted for writing. | |
472 | */ | |
473 | static int | |
474 | sclp_vt220_write(struct tty_struct *tty, const unsigned char *buf, int count) | |
475 | { | |
d1e23375 | 476 | return __sclp_vt220_write(buf, count, 1, 0, 1); |
1da177e4 LT |
477 | } |
478 | ||
479 | #define SCLP_VT220_SESSION_ENDED 0x01 | |
480 | #define SCLP_VT220_SESSION_STARTED 0x80 | |
481 | #define SCLP_VT220_SESSION_DATA 0x00 | |
482 | ||
1d3f9094 HB |
483 | #ifdef CONFIG_MAGIC_SYSRQ |
484 | ||
485 | static int sysrq_pressed; | |
486 | static struct sysrq_work sysrq; | |
487 | ||
488 | static void sclp_vt220_reset_session(void) | |
489 | { | |
490 | sysrq_pressed = 0; | |
491 | } | |
492 | ||
493 | static void sclp_vt220_handle_input(const char *buffer, unsigned int count) | |
494 | { | |
495 | int i; | |
496 | ||
497 | for (i = 0; i < count; i++) { | |
498 | /* Handle magic sys request */ | |
499 | if (buffer[i] == ('O' ^ 0100)) { /* CTRL-O */ | |
500 | /* | |
501 | * If pressed again, reset sysrq_pressed | |
502 | * and flip CTRL-O character | |
503 | */ | |
504 | sysrq_pressed = !sysrq_pressed; | |
505 | if (sysrq_pressed) | |
506 | continue; | |
507 | } else if (sysrq_pressed) { | |
508 | sysrq.key = buffer[i]; | |
509 | schedule_sysrq_work(&sysrq); | |
510 | sysrq_pressed = 0; | |
511 | continue; | |
512 | } | |
513 | tty_insert_flip_char(&sclp_vt220_port, buffer[i], 0); | |
514 | } | |
515 | } | |
516 | ||
517 | #else | |
518 | ||
519 | static void sclp_vt220_reset_session(void) | |
520 | { | |
521 | } | |
522 | ||
523 | static void sclp_vt220_handle_input(const char *buffer, unsigned int count) | |
524 | { | |
525 | tty_insert_flip_string(&sclp_vt220_port, buffer, count); | |
526 | } | |
527 | ||
528 | #endif | |
529 | ||
1da177e4 LT |
530 | /* |
531 | * Called by the SCLP to report incoming event buffers. | |
532 | */ | |
533 | static void | |
534 | sclp_vt220_receiver_fn(struct evbuf_header *evbuf) | |
535 | { | |
536 | char *buffer; | |
537 | unsigned int count; | |
538 | ||
1da177e4 LT |
539 | buffer = (char *) ((addr_t) evbuf + sizeof(struct evbuf_header)); |
540 | count = evbuf->length - sizeof(struct evbuf_header); | |
541 | ||
542 | switch (*buffer) { | |
543 | case SCLP_VT220_SESSION_ENDED: | |
544 | case SCLP_VT220_SESSION_STARTED: | |
1d3f9094 | 545 | sclp_vt220_reset_session(); |
1da177e4 LT |
546 | break; |
547 | case SCLP_VT220_SESSION_DATA: | |
548 | /* Send input to line discipline */ | |
549 | buffer++; | |
550 | count--; | |
1d3f9094 | 551 | sclp_vt220_handle_input(buffer, count); |
2e124b4a | 552 | tty_flip_buffer_push(&sclp_vt220_port); |
1da177e4 LT |
553 | break; |
554 | } | |
555 | } | |
556 | ||
557 | /* | |
558 | * This routine is called when a particular tty device is opened. | |
559 | */ | |
560 | static int | |
561 | sclp_vt220_open(struct tty_struct *tty, struct file *filp) | |
562 | { | |
563 | if (tty->count == 1) { | |
092f7377 | 564 | tty_port_tty_set(&sclp_vt220_port, tty); |
d6c53c0e | 565 | sclp_vt220_port.low_latency = 0; |
0b665d77 HB |
566 | if (!tty->winsize.ws_row && !tty->winsize.ws_col) { |
567 | tty->winsize.ws_row = 24; | |
568 | tty->winsize.ws_col = 80; | |
569 | } | |
1da177e4 LT |
570 | } |
571 | return 0; | |
572 | } | |
573 | ||
574 | /* | |
575 | * This routine is called when a particular tty device is closed. | |
576 | */ | |
577 | static void | |
578 | sclp_vt220_close(struct tty_struct *tty, struct file *filp) | |
579 | { | |
b538c4ea | 580 | if (tty->count == 1) |
092f7377 | 581 | tty_port_tty_set(&sclp_vt220_port, NULL); |
1da177e4 LT |
582 | } |
583 | ||
584 | /* | |
585 | * This routine is called by the kernel to write a single | |
586 | * character to the tty device. If the kernel uses this routine, | |
587 | * it must call the flush_chars() routine (if defined) when it is | |
588 | * done stuffing characters into the driver. | |
1da177e4 | 589 | */ |
9e7c9a19 | 590 | static int |
1da177e4 LT |
591 | sclp_vt220_put_char(struct tty_struct *tty, unsigned char ch) |
592 | { | |
d4820e44 | 593 | return __sclp_vt220_write(&ch, 1, 0, 0, 1); |
1da177e4 LT |
594 | } |
595 | ||
596 | /* | |
597 | * This routine is called by the kernel after it has written a | |
598 | * series of characters to the tty device using put_char(). | |
599 | */ | |
600 | static void | |
601 | sclp_vt220_flush_chars(struct tty_struct *tty) | |
602 | { | |
62b74942 | 603 | if (!sclp_vt220_queue_running) |
1da177e4 LT |
604 | sclp_vt220_emit_current(); |
605 | else | |
606 | sclp_vt220_flush_later = 1; | |
607 | } | |
608 | ||
609 | /* | |
610 | * This routine returns the numbers of characters the tty driver | |
611 | * will accept for queuing to be written. This number is subject | |
612 | * to change as output buffers get emptied, or if the output flow | |
613 | * control is acted. | |
614 | */ | |
615 | static int | |
616 | sclp_vt220_write_room(struct tty_struct *tty) | |
617 | { | |
618 | unsigned long flags; | |
619 | struct list_head *l; | |
620 | int count; | |
621 | ||
622 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
623 | count = 0; | |
624 | if (sclp_vt220_current_request != NULL) | |
625 | count = sclp_vt220_space_left(sclp_vt220_current_request); | |
626 | list_for_each(l, &sclp_vt220_empty) | |
627 | count += SCLP_VT220_MAX_CHARS_PER_BUFFER; | |
628 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
629 | return count; | |
630 | } | |
631 | ||
632 | /* | |
633 | * Return number of buffered chars. | |
634 | */ | |
635 | static int | |
636 | sclp_vt220_chars_in_buffer(struct tty_struct *tty) | |
637 | { | |
638 | unsigned long flags; | |
639 | struct list_head *l; | |
640 | struct sclp_vt220_request *r; | |
641 | int count; | |
642 | ||
643 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
644 | count = 0; | |
645 | if (sclp_vt220_current_request != NULL) | |
646 | count = sclp_vt220_chars_stored(sclp_vt220_current_request); | |
647 | list_for_each(l, &sclp_vt220_outqueue) { | |
648 | r = list_entry(l, struct sclp_vt220_request, list); | |
649 | count += sclp_vt220_chars_stored(r); | |
650 | } | |
651 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
652 | return count; | |
653 | } | |
654 | ||
1da177e4 LT |
655 | /* |
656 | * Pass on all buffers to the hardware. Return only when there are no more | |
657 | * buffers pending. | |
658 | */ | |
659 | static void | |
660 | sclp_vt220_flush_buffer(struct tty_struct *tty) | |
661 | { | |
662 | sclp_vt220_emit_current(); | |
663 | } | |
664 | ||
ad211790 PO |
665 | /* Release allocated pages. */ |
666 | static void __init __sclp_vt220_free_pages(void) | |
5aaaf9f0 HC |
667 | { |
668 | struct list_head *page, *p; | |
669 | ||
670 | list_for_each_safe(page, p, &sclp_vt220_empty) { | |
671 | list_del(page); | |
5c0792f6 | 672 | free_page((unsigned long) page); |
5aaaf9f0 HC |
673 | } |
674 | } | |
675 | ||
ad211790 PO |
676 | /* Release memory and unregister from sclp core. Controlled by init counting - |
677 | * only the last invoker will actually perform these actions. */ | |
678 | static void __init __sclp_vt220_cleanup(void) | |
679 | { | |
680 | sclp_vt220_init_count--; | |
681 | if (sclp_vt220_init_count != 0) | |
682 | return; | |
683 | sclp_unregister(&sclp_vt220_register); | |
684 | __sclp_vt220_free_pages(); | |
191c5f10 | 685 | tty_port_destroy(&sclp_vt220_port); |
ad211790 PO |
686 | } |
687 | ||
688 | /* Allocate buffer pages and register with sclp core. Controlled by init | |
689 | * counting - only the first invoker will actually perform these actions. */ | |
690 | static int __init __sclp_vt220_init(int num_pages) | |
1da177e4 LT |
691 | { |
692 | void *page; | |
693 | int i; | |
59eb1ca7 | 694 | int rc; |
1da177e4 | 695 | |
ad211790 PO |
696 | sclp_vt220_init_count++; |
697 | if (sclp_vt220_init_count != 1) | |
1da177e4 | 698 | return 0; |
1da177e4 LT |
699 | spin_lock_init(&sclp_vt220_lock); |
700 | INIT_LIST_HEAD(&sclp_vt220_empty); | |
701 | INIT_LIST_HEAD(&sclp_vt220_outqueue); | |
1da177e4 | 702 | init_timer(&sclp_vt220_timer); |
092f7377 | 703 | tty_port_init(&sclp_vt220_port); |
1da177e4 LT |
704 | sclp_vt220_current_request = NULL; |
705 | sclp_vt220_buffered_chars = 0; | |
1da177e4 LT |
706 | sclp_vt220_flush_later = 0; |
707 | ||
708 | /* Allocate pages for output buffering */ | |
5c0792f6 | 709 | rc = -ENOMEM; |
5aaaf9f0 | 710 | for (i = 0; i < num_pages; i++) { |
5c0792f6 HC |
711 | page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); |
712 | if (!page) | |
ad211790 | 713 | goto out; |
5c0792f6 | 714 | list_add_tail(page, &sclp_vt220_empty); |
1da177e4 | 715 | } |
59eb1ca7 | 716 | rc = sclp_register(&sclp_vt220_register); |
ad211790 | 717 | out: |
59eb1ca7 | 718 | if (rc) { |
ad211790 PO |
719 | __sclp_vt220_free_pages(); |
720 | sclp_vt220_init_count--; | |
191c5f10 | 721 | tty_port_destroy(&sclp_vt220_port); |
59eb1ca7 CB |
722 | } |
723 | return rc; | |
1da177e4 LT |
724 | } |
725 | ||
b68e31d0 | 726 | static const struct tty_operations sclp_vt220_ops = { |
1da177e4 LT |
727 | .open = sclp_vt220_open, |
728 | .close = sclp_vt220_close, | |
729 | .write = sclp_vt220_write, | |
730 | .put_char = sclp_vt220_put_char, | |
731 | .flush_chars = sclp_vt220_flush_chars, | |
732 | .write_room = sclp_vt220_write_room, | |
733 | .chars_in_buffer = sclp_vt220_chars_in_buffer, | |
5aaaf9f0 | 734 | .flush_buffer = sclp_vt220_flush_buffer, |
1da177e4 LT |
735 | }; |
736 | ||
737 | /* | |
738 | * Register driver with SCLP and Linux and initialize internal tty structures. | |
739 | */ | |
5aaaf9f0 | 740 | static int __init sclp_vt220_tty_init(void) |
1da177e4 LT |
741 | { |
742 | struct tty_driver *driver; | |
743 | int rc; | |
744 | ||
745 | /* Note: we're not testing for CONSOLE_IS_SCLP here to preserve | |
746 | * symmetry between VM and LPAR systems regarding ttyS1. */ | |
747 | driver = alloc_tty_driver(1); | |
748 | if (!driver) | |
749 | return -ENOMEM; | |
ad211790 | 750 | rc = __sclp_vt220_init(MAX_KMEM_PAGES); |
5aaaf9f0 HC |
751 | if (rc) |
752 | goto out_driver; | |
1da177e4 | 753 | |
1da177e4 LT |
754 | driver->driver_name = SCLP_VT220_DRIVER_NAME; |
755 | driver->name = SCLP_VT220_DEVICE_NAME; | |
756 | driver->major = SCLP_VT220_MAJOR; | |
757 | driver->minor_start = SCLP_VT220_MINOR; | |
758 | driver->type = TTY_DRIVER_TYPE_SYSTEM; | |
759 | driver->subtype = SYSTEM_TYPE_TTY; | |
760 | driver->init_termios = tty_std_termios; | |
761 | driver->flags = TTY_DRIVER_REAL_RAW; | |
762 | tty_set_operations(driver, &sclp_vt220_ops); | |
b19e2ca7 | 763 | tty_port_link_device(&sclp_vt220_port, driver, 0); |
1da177e4 LT |
764 | |
765 | rc = tty_register_driver(driver); | |
a12c53f4 | 766 | if (rc) |
59eb1ca7 | 767 | goto out_init; |
e106e4ea PO |
768 | rc = sclp_register(&sclp_vt220_register_input); |
769 | if (rc) | |
770 | goto out_reg; | |
1da177e4 LT |
771 | sclp_vt220_driver = driver; |
772 | return 0; | |
1da177e4 | 773 | |
e106e4ea PO |
774 | out_reg: |
775 | tty_unregister_driver(driver); | |
5aaaf9f0 | 776 | out_init: |
ad211790 | 777 | __sclp_vt220_cleanup(); |
5aaaf9f0 HC |
778 | out_driver: |
779 | put_tty_driver(driver); | |
780 | return rc; | |
781 | } | |
782 | __initcall(sclp_vt220_tty_init); | |
1da177e4 | 783 | |
b3b59d33 HC |
784 | static void __sclp_vt220_flush_buffer(void) |
785 | { | |
786 | unsigned long flags; | |
787 | ||
788 | sclp_vt220_emit_current(); | |
789 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
790 | if (timer_pending(&sclp_vt220_timer)) | |
791 | del_timer(&sclp_vt220_timer); | |
62b74942 | 792 | while (sclp_vt220_queue_running) { |
b3b59d33 HC |
793 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
794 | sclp_sync_wait(); | |
795 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
796 | } | |
797 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
798 | } | |
799 | ||
62b74942 MH |
800 | /* |
801 | * Resume console: If there are cached messages, emit them. | |
802 | */ | |
803 | static void sclp_vt220_resume(void) | |
804 | { | |
805 | unsigned long flags; | |
806 | ||
807 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
808 | sclp_vt220_suspended = 0; | |
809 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
810 | sclp_vt220_emit_current(); | |
811 | } | |
812 | ||
813 | /* | |
814 | * Suspend console: Set suspend flag and flush console | |
815 | */ | |
816 | static void sclp_vt220_suspend(void) | |
817 | { | |
818 | unsigned long flags; | |
819 | ||
820 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
821 | sclp_vt220_suspended = 1; | |
822 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
823 | __sclp_vt220_flush_buffer(); | |
824 | } | |
825 | ||
826 | static void sclp_vt220_pm_event_fn(struct sclp_register *reg, | |
827 | enum sclp_pm_event sclp_pm_event) | |
828 | { | |
829 | switch (sclp_pm_event) { | |
830 | case SCLP_PM_EVENT_FREEZE: | |
831 | sclp_vt220_suspend(); | |
832 | break; | |
833 | case SCLP_PM_EVENT_RESTORE: | |
834 | case SCLP_PM_EVENT_THAW: | |
835 | sclp_vt220_resume(); | |
836 | break; | |
837 | } | |
838 | } | |
839 | ||
ac522b63 MH |
840 | #ifdef CONFIG_SCLP_VT220_CONSOLE |
841 | ||
842 | static void | |
843 | sclp_vt220_con_write(struct console *con, const char *buf, unsigned int count) | |
844 | { | |
845 | __sclp_vt220_write((const unsigned char *) buf, count, 1, 1, 0); | |
846 | } | |
847 | ||
848 | static struct tty_driver * | |
849 | sclp_vt220_con_device(struct console *c, int *index) | |
850 | { | |
851 | *index = 0; | |
852 | return sclp_vt220_driver; | |
853 | } | |
854 | ||
2332ce1a HS |
855 | static int |
856 | sclp_vt220_notify(struct notifier_block *self, | |
857 | unsigned long event, void *data) | |
1da177e4 LT |
858 | { |
859 | __sclp_vt220_flush_buffer(); | |
2332ce1a | 860 | return NOTIFY_OK; |
1da177e4 LT |
861 | } |
862 | ||
2332ce1a HS |
863 | static struct notifier_block on_panic_nb = { |
864 | .notifier_call = sclp_vt220_notify, | |
865 | .priority = 1, | |
866 | }; | |
867 | ||
868 | static struct notifier_block on_reboot_nb = { | |
869 | .notifier_call = sclp_vt220_notify, | |
870 | .priority = 1, | |
871 | }; | |
872 | ||
1da177e4 LT |
873 | /* Structure needed to register with printk */ |
874 | static struct console sclp_vt220_console = | |
875 | { | |
876 | .name = SCLP_VT220_CONSOLE_NAME, | |
877 | .write = sclp_vt220_con_write, | |
878 | .device = sclp_vt220_con_device, | |
1da177e4 LT |
879 | .flags = CON_PRINTBUFFER, |
880 | .index = SCLP_VT220_CONSOLE_INDEX | |
881 | }; | |
882 | ||
883 | static int __init | |
884 | sclp_vt220_con_init(void) | |
885 | { | |
886 | int rc; | |
887 | ||
25b41a7b | 888 | rc = __sclp_vt220_init(sclp_console_pages); |
1da177e4 LT |
889 | if (rc) |
890 | return rc; | |
891 | /* Attach linux console */ | |
2332ce1a HS |
892 | atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb); |
893 | register_reboot_notifier(&on_reboot_nb); | |
1da177e4 LT |
894 | register_console(&sclp_vt220_console); |
895 | return 0; | |
896 | } | |
897 | ||
898 | console_initcall(sclp_vt220_con_init); | |
899 | #endif /* CONFIG_SCLP_VT220_CONSOLE */ | |
900 |