Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * drivers/s390/char/sclp_vt220.c | |
3 | * SCLP VT220 terminal driver. | |
4 | * | |
5 | * S390 version | |
59eb1ca7 | 6 | * Copyright IBM Corp. 2003,2008 |
1da177e4 LT |
7 | * Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com> |
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> | |
16 | #include <linux/tty.h> | |
17 | #include <linux/tty_driver.h> | |
33f0f88f | 18 | #include <linux/tty_flip.h> |
1da177e4 LT |
19 | #include <linux/errno.h> |
20 | #include <linux/mm.h> | |
21 | #include <linux/major.h> | |
22 | #include <linux/console.h> | |
23 | #include <linux/kdev_t.h> | |
24 | #include <linux/bootmem.h> | |
25 | #include <linux/interrupt.h> | |
26 | #include <linux/init.h> | |
2332ce1a HS |
27 | #include <linux/reboot.h> |
28 | ||
1da177e4 LT |
29 | #include <asm/uaccess.h> |
30 | #include "sclp.h" | |
31 | ||
1da177e4 LT |
32 | #define SCLP_VT220_MAJOR TTY_MAJOR |
33 | #define SCLP_VT220_MINOR 65 | |
34 | #define SCLP_VT220_DRIVER_NAME "sclp_vt220" | |
35 | #define SCLP_VT220_DEVICE_NAME "ttysclp" | |
36 | #define SCLP_VT220_CONSOLE_NAME "ttyS" | |
37 | #define SCLP_VT220_CONSOLE_INDEX 1 /* console=ttyS1 */ | |
38 | #define SCLP_VT220_BUF_SIZE 80 | |
39 | ||
40 | /* Representation of a single write request */ | |
41 | struct sclp_vt220_request { | |
42 | struct list_head list; | |
43 | struct sclp_req sclp_req; | |
44 | int retry_count; | |
45 | }; | |
46 | ||
47 | /* VT220 SCCB */ | |
48 | struct sclp_vt220_sccb { | |
49 | struct sccb_header header; | |
50 | struct evbuf_header evbuf; | |
51 | }; | |
52 | ||
53 | #define SCLP_VT220_MAX_CHARS_PER_BUFFER (PAGE_SIZE - \ | |
54 | sizeof(struct sclp_vt220_request) - \ | |
55 | sizeof(struct sclp_vt220_sccb)) | |
56 | ||
57 | /* Structures and data needed to register tty driver */ | |
58 | static struct tty_driver *sclp_vt220_driver; | |
59 | ||
60 | /* The tty_struct that the kernel associated with us */ | |
61 | static struct tty_struct *sclp_vt220_tty; | |
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 | ||
72 | /* Number of requests in outqueue */ | |
73 | static int sclp_vt220_outqueue_count; | |
74 | ||
1da177e4 LT |
75 | /* Timer used for delaying write requests to merge subsequent messages into |
76 | * a single buffer */ | |
77 | static struct timer_list sclp_vt220_timer; | |
78 | ||
79 | /* Pointer to current request buffer which has been partially filled but not | |
80 | * yet sent */ | |
81 | static struct sclp_vt220_request *sclp_vt220_current_request; | |
82 | ||
83 | /* Number of characters in current request buffer */ | |
84 | static int sclp_vt220_buffered_chars; | |
85 | ||
ad211790 PO |
86 | /* Counter controlling core driver initialization. */ |
87 | static int __initdata sclp_vt220_init_count; | |
1da177e4 LT |
88 | |
89 | /* Flag indicating that sclp_vt220_current_request should really | |
90 | * have been already queued but wasn't because the SCLP was processing | |
91 | * another buffer */ | |
92 | static int sclp_vt220_flush_later; | |
93 | ||
94 | static void sclp_vt220_receiver_fn(struct evbuf_header *evbuf); | |
95 | static int __sclp_vt220_emit(struct sclp_vt220_request *request); | |
96 | static void sclp_vt220_emit_current(void); | |
97 | ||
98 | /* Registration structure for our interest in SCLP event buffers */ | |
99 | static struct sclp_register sclp_vt220_register = { | |
6d4740c8 SH |
100 | .send_mask = EVTYP_VT220MSG_MASK, |
101 | .receive_mask = EVTYP_VT220MSG_MASK, | |
1da177e4 LT |
102 | .state_change_fn = NULL, |
103 | .receiver_fn = sclp_vt220_receiver_fn | |
104 | }; | |
105 | ||
106 | ||
107 | /* | |
108 | * Put provided request buffer back into queue and check emit pending | |
109 | * buffers if necessary. | |
110 | */ | |
111 | static void | |
112 | sclp_vt220_process_queue(struct sclp_vt220_request *request) | |
113 | { | |
114 | unsigned long flags; | |
115 | void *page; | |
116 | ||
117 | do { | |
118 | /* Put buffer back to list of empty buffers */ | |
119 | page = request->sclp_req.sccb; | |
120 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
121 | /* Move request from outqueue to empty queue */ | |
122 | list_del(&request->list); | |
123 | sclp_vt220_outqueue_count--; | |
124 | list_add_tail((struct list_head *) page, &sclp_vt220_empty); | |
125 | /* Check if there is a pending buffer on the out queue. */ | |
126 | request = NULL; | |
127 | if (!list_empty(&sclp_vt220_outqueue)) | |
128 | request = list_entry(sclp_vt220_outqueue.next, | |
129 | struct sclp_vt220_request, list); | |
130 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
131 | } while (request && __sclp_vt220_emit(request)); | |
132 | if (request == NULL && sclp_vt220_flush_later) | |
133 | sclp_vt220_emit_current(); | |
1da177e4 LT |
134 | /* Check if the tty needs a wake up call */ |
135 | if (sclp_vt220_tty != NULL) { | |
136 | tty_wakeup(sclp_vt220_tty); | |
137 | } | |
138 | } | |
139 | ||
140 | #define SCLP_BUFFER_MAX_RETRY 1 | |
141 | ||
142 | /* | |
143 | * Callback through which the result of a write request is reported by the | |
144 | * SCLP. | |
145 | */ | |
146 | static void | |
147 | sclp_vt220_callback(struct sclp_req *request, void *data) | |
148 | { | |
149 | struct sclp_vt220_request *vt220_request; | |
150 | struct sclp_vt220_sccb *sccb; | |
151 | ||
152 | vt220_request = (struct sclp_vt220_request *) data; | |
153 | if (request->status == SCLP_REQ_FAILED) { | |
154 | sclp_vt220_process_queue(vt220_request); | |
155 | return; | |
156 | } | |
157 | sccb = (struct sclp_vt220_sccb *) vt220_request->sclp_req.sccb; | |
158 | ||
159 | /* Check SCLP response code and choose suitable action */ | |
160 | switch (sccb->header.response_code) { | |
161 | case 0x0020 : | |
162 | break; | |
163 | ||
164 | case 0x05f0: /* Target resource in improper state */ | |
165 | break; | |
166 | ||
167 | case 0x0340: /* Contained SCLP equipment check */ | |
168 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) | |
169 | break; | |
170 | /* Remove processed buffers and requeue rest */ | |
171 | if (sclp_remove_processed((struct sccb_header *) sccb) > 0) { | |
172 | /* Not all buffers were processed */ | |
173 | sccb->header.response_code = 0x0000; | |
174 | vt220_request->sclp_req.status = SCLP_REQ_FILLED; | |
175 | if (sclp_add_request(request) == 0) | |
176 | return; | |
177 | } | |
178 | break; | |
179 | ||
180 | case 0x0040: /* SCLP equipment check */ | |
181 | if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY) | |
182 | break; | |
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 | break; | |
188 | ||
189 | default: | |
190 | break; | |
191 | } | |
192 | sclp_vt220_process_queue(vt220_request); | |
193 | } | |
194 | ||
195 | /* | |
196 | * Emit vt220 request buffer to SCLP. Return zero on success, non-zero | |
197 | * otherwise. | |
198 | */ | |
199 | static int | |
200 | __sclp_vt220_emit(struct sclp_vt220_request *request) | |
201 | { | |
d082d3ce | 202 | if (!(sclp_vt220_register.sclp_receive_mask & EVTYP_VT220MSG_MASK)) { |
1da177e4 LT |
203 | request->sclp_req.status = SCLP_REQ_FAILED; |
204 | return -EIO; | |
205 | } | |
ab14de6c | 206 | request->sclp_req.command = SCLP_CMDW_WRITE_EVENT_DATA; |
1da177e4 LT |
207 | request->sclp_req.status = SCLP_REQ_FILLED; |
208 | request->sclp_req.callback = sclp_vt220_callback; | |
209 | request->sclp_req.callback_data = (void *) request; | |
210 | ||
211 | return sclp_add_request(&request->sclp_req); | |
212 | } | |
213 | ||
214 | /* | |
215 | * Queue and emit given request. | |
216 | */ | |
217 | static void | |
218 | sclp_vt220_emit(struct sclp_vt220_request *request) | |
219 | { | |
220 | unsigned long flags; | |
221 | int count; | |
222 | ||
223 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
224 | list_add_tail(&request->list, &sclp_vt220_outqueue); | |
225 | count = sclp_vt220_outqueue_count++; | |
226 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
227 | /* Emit only the first buffer immediately - callback takes care of | |
228 | * the rest */ | |
229 | if (count == 0 && __sclp_vt220_emit(request)) | |
230 | sclp_vt220_process_queue(request); | |
231 | } | |
232 | ||
233 | /* | |
234 | * Queue and emit current request. Return zero on success, non-zero otherwise. | |
235 | */ | |
236 | static void | |
237 | sclp_vt220_emit_current(void) | |
238 | { | |
239 | unsigned long flags; | |
240 | struct sclp_vt220_request *request; | |
241 | struct sclp_vt220_sccb *sccb; | |
242 | ||
243 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
244 | request = NULL; | |
245 | if (sclp_vt220_current_request != NULL) { | |
246 | sccb = (struct sclp_vt220_sccb *) | |
247 | sclp_vt220_current_request->sclp_req.sccb; | |
248 | /* Only emit buffers with content */ | |
249 | if (sccb->header.length != sizeof(struct sclp_vt220_sccb)) { | |
250 | request = sclp_vt220_current_request; | |
251 | sclp_vt220_current_request = NULL; | |
252 | if (timer_pending(&sclp_vt220_timer)) | |
253 | del_timer(&sclp_vt220_timer); | |
254 | } | |
255 | sclp_vt220_flush_later = 0; | |
256 | } | |
257 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
258 | if (request != NULL) | |
259 | sclp_vt220_emit(request); | |
260 | } | |
261 | ||
262 | #define SCLP_NORMAL_WRITE 0x00 | |
263 | ||
264 | /* | |
265 | * Helper function to initialize a page with the sclp request structure. | |
266 | */ | |
267 | static struct sclp_vt220_request * | |
268 | sclp_vt220_initialize_page(void *page) | |
269 | { | |
270 | struct sclp_vt220_request *request; | |
271 | struct sclp_vt220_sccb *sccb; | |
272 | ||
273 | /* Place request structure at end of page */ | |
274 | request = ((struct sclp_vt220_request *) | |
275 | ((addr_t) page + PAGE_SIZE)) - 1; | |
276 | request->retry_count = 0; | |
277 | request->sclp_req.sccb = page; | |
278 | /* SCCB goes at start of page */ | |
279 | sccb = (struct sclp_vt220_sccb *) page; | |
280 | memset((void *) sccb, 0, sizeof(struct sclp_vt220_sccb)); | |
281 | sccb->header.length = sizeof(struct sclp_vt220_sccb); | |
282 | sccb->header.function_code = SCLP_NORMAL_WRITE; | |
283 | sccb->header.response_code = 0x0000; | |
6d4740c8 | 284 | sccb->evbuf.type = EVTYP_VT220MSG; |
1da177e4 LT |
285 | sccb->evbuf.length = sizeof(struct evbuf_header); |
286 | ||
287 | return request; | |
288 | } | |
289 | ||
290 | static inline unsigned int | |
291 | sclp_vt220_space_left(struct sclp_vt220_request *request) | |
292 | { | |
293 | struct sclp_vt220_sccb *sccb; | |
294 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
295 | return PAGE_SIZE - sizeof(struct sclp_vt220_request) - | |
296 | sccb->header.length; | |
297 | } | |
298 | ||
299 | static inline unsigned int | |
300 | sclp_vt220_chars_stored(struct sclp_vt220_request *request) | |
301 | { | |
302 | struct sclp_vt220_sccb *sccb; | |
303 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
304 | return sccb->evbuf.length - sizeof(struct evbuf_header); | |
305 | } | |
306 | ||
307 | /* | |
308 | * Add msg to buffer associated with request. Return the number of characters | |
309 | * added. | |
310 | */ | |
311 | static int | |
312 | sclp_vt220_add_msg(struct sclp_vt220_request *request, | |
313 | const unsigned char *msg, int count, int convertlf) | |
314 | { | |
315 | struct sclp_vt220_sccb *sccb; | |
316 | void *buffer; | |
317 | unsigned char c; | |
318 | int from; | |
319 | int to; | |
320 | ||
321 | if (count > sclp_vt220_space_left(request)) | |
322 | count = sclp_vt220_space_left(request); | |
323 | if (count <= 0) | |
324 | return 0; | |
325 | ||
326 | sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb; | |
327 | buffer = (void *) ((addr_t) sccb + sccb->header.length); | |
328 | ||
329 | if (convertlf) { | |
330 | /* Perform Linefeed conversion (0x0a -> 0x0a 0x0d)*/ | |
331 | for (from=0, to=0; | |
332 | (from < count) && (to < sclp_vt220_space_left(request)); | |
333 | from++) { | |
334 | /* Retrieve character */ | |
335 | c = msg[from]; | |
336 | /* Perform conversion */ | |
337 | if (c == 0x0a) { | |
338 | if (to + 1 < sclp_vt220_space_left(request)) { | |
339 | ((unsigned char *) buffer)[to++] = c; | |
340 | ((unsigned char *) buffer)[to++] = 0x0d; | |
341 | } else | |
342 | break; | |
343 | ||
344 | } else | |
345 | ((unsigned char *) buffer)[to++] = c; | |
346 | } | |
347 | sccb->header.length += to; | |
348 | sccb->evbuf.length += to; | |
349 | return from; | |
350 | } else { | |
351 | memcpy(buffer, (const void *) msg, count); | |
352 | sccb->header.length += count; | |
353 | sccb->evbuf.length += count; | |
354 | return count; | |
355 | } | |
356 | } | |
357 | ||
358 | /* | |
359 | * Emit buffer after having waited long enough for more data to arrive. | |
360 | */ | |
361 | static void | |
362 | sclp_vt220_timeout(unsigned long data) | |
363 | { | |
364 | sclp_vt220_emit_current(); | |
365 | } | |
366 | ||
fa331ffc | 367 | #define BUFFER_MAX_DELAY HZ/20 |
1da177e4 LT |
368 | |
369 | /* | |
370 | * Internal implementation of the write function. Write COUNT bytes of data | |
371 | * from memory at BUF | |
372 | * to the SCLP interface. In case that the data does not fit into the current | |
373 | * write buffer, emit the current one and allocate a new one. If there are no | |
374 | * more empty buffers available, wait until one gets emptied. If DO_SCHEDULE | |
375 | * is non-zero, the buffer will be scheduled for emitting after a timeout - | |
376 | * otherwise the user has to explicitly call the flush function. | |
377 | * A non-zero CONVERTLF parameter indicates that 0x0a characters in the message | |
378 | * buffer should be converted to 0x0a 0x0d. After completion, return the number | |
379 | * of bytes written. | |
380 | */ | |
381 | static int | |
382 | __sclp_vt220_write(const unsigned char *buf, int count, int do_schedule, | |
d4820e44 | 383 | int convertlf, int may_fail) |
1da177e4 LT |
384 | { |
385 | unsigned long flags; | |
386 | void *page; | |
387 | int written; | |
388 | int overall_written; | |
389 | ||
390 | if (count <= 0) | |
391 | return 0; | |
392 | overall_written = 0; | |
393 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
394 | do { | |
d4820e44 | 395 | /* Create an sclp output buffer if none exists yet */ |
1da177e4 LT |
396 | if (sclp_vt220_current_request == NULL) { |
397 | while (list_empty(&sclp_vt220_empty)) { | |
d1e23375 | 398 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); |
d4820e44 HC |
399 | if (may_fail) |
400 | goto out; | |
1da177e4 | 401 | else |
d4820e44 | 402 | sclp_sync_wait(); |
1da177e4 LT |
403 | spin_lock_irqsave(&sclp_vt220_lock, flags); |
404 | } | |
405 | page = (void *) sclp_vt220_empty.next; | |
406 | list_del((struct list_head *) page); | |
407 | sclp_vt220_current_request = | |
408 | sclp_vt220_initialize_page(page); | |
409 | } | |
410 | /* Try to write the string to the current request buffer */ | |
411 | written = sclp_vt220_add_msg(sclp_vt220_current_request, | |
412 | buf, count, convertlf); | |
413 | overall_written += written; | |
414 | if (written == count) | |
415 | break; | |
416 | /* | |
417 | * Not all characters could be written to the current | |
418 | * output buffer. Emit the buffer, create a new buffer | |
419 | * and then output the rest of the string. | |
420 | */ | |
421 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
422 | sclp_vt220_emit_current(); | |
423 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
424 | buf += written; | |
425 | count -= written; | |
426 | } while (count > 0); | |
427 | /* Setup timer to output current console buffer after some time */ | |
428 | if (sclp_vt220_current_request != NULL && | |
429 | !timer_pending(&sclp_vt220_timer) && do_schedule) { | |
430 | sclp_vt220_timer.function = sclp_vt220_timeout; | |
431 | sclp_vt220_timer.data = 0UL; | |
432 | sclp_vt220_timer.expires = jiffies + BUFFER_MAX_DELAY; | |
433 | add_timer(&sclp_vt220_timer); | |
434 | } | |
435 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
d4820e44 | 436 | out: |
1da177e4 LT |
437 | return overall_written; |
438 | } | |
439 | ||
440 | /* | |
441 | * This routine is called by the kernel to write a series of | |
442 | * characters to the tty device. The characters may come from | |
443 | * user space or kernel space. This routine will return the | |
444 | * number of characters actually accepted for writing. | |
445 | */ | |
446 | static int | |
447 | sclp_vt220_write(struct tty_struct *tty, const unsigned char *buf, int count) | |
448 | { | |
d1e23375 | 449 | return __sclp_vt220_write(buf, count, 1, 0, 1); |
1da177e4 LT |
450 | } |
451 | ||
452 | #define SCLP_VT220_SESSION_ENDED 0x01 | |
453 | #define SCLP_VT220_SESSION_STARTED 0x80 | |
454 | #define SCLP_VT220_SESSION_DATA 0x00 | |
455 | ||
456 | /* | |
457 | * Called by the SCLP to report incoming event buffers. | |
458 | */ | |
459 | static void | |
460 | sclp_vt220_receiver_fn(struct evbuf_header *evbuf) | |
461 | { | |
462 | char *buffer; | |
463 | unsigned int count; | |
464 | ||
465 | /* Ignore input if device is not open */ | |
466 | if (sclp_vt220_tty == NULL) | |
467 | return; | |
468 | ||
469 | buffer = (char *) ((addr_t) evbuf + sizeof(struct evbuf_header)); | |
470 | count = evbuf->length - sizeof(struct evbuf_header); | |
471 | ||
472 | switch (*buffer) { | |
473 | case SCLP_VT220_SESSION_ENDED: | |
474 | case SCLP_VT220_SESSION_STARTED: | |
475 | break; | |
476 | case SCLP_VT220_SESSION_DATA: | |
477 | /* Send input to line discipline */ | |
478 | buffer++; | |
479 | count--; | |
33f0f88f | 480 | tty_insert_flip_string(sclp_vt220_tty, buffer, count); |
1da177e4 LT |
481 | tty_flip_buffer_push(sclp_vt220_tty); |
482 | break; | |
483 | } | |
484 | } | |
485 | ||
486 | /* | |
487 | * This routine is called when a particular tty device is opened. | |
488 | */ | |
489 | static int | |
490 | sclp_vt220_open(struct tty_struct *tty, struct file *filp) | |
491 | { | |
492 | if (tty->count == 1) { | |
493 | sclp_vt220_tty = tty; | |
494 | tty->driver_data = kmalloc(SCLP_VT220_BUF_SIZE, GFP_KERNEL); | |
495 | if (tty->driver_data == NULL) | |
496 | return -ENOMEM; | |
497 | tty->low_latency = 0; | |
498 | } | |
499 | return 0; | |
500 | } | |
501 | ||
502 | /* | |
503 | * This routine is called when a particular tty device is closed. | |
504 | */ | |
505 | static void | |
506 | sclp_vt220_close(struct tty_struct *tty, struct file *filp) | |
507 | { | |
508 | if (tty->count == 1) { | |
509 | sclp_vt220_tty = NULL; | |
510 | kfree(tty->driver_data); | |
511 | tty->driver_data = NULL; | |
512 | } | |
513 | } | |
514 | ||
515 | /* | |
516 | * This routine is called by the kernel to write a single | |
517 | * character to the tty device. If the kernel uses this routine, | |
518 | * it must call the flush_chars() routine (if defined) when it is | |
519 | * done stuffing characters into the driver. | |
1da177e4 | 520 | */ |
9e7c9a19 | 521 | static int |
1da177e4 LT |
522 | sclp_vt220_put_char(struct tty_struct *tty, unsigned char ch) |
523 | { | |
d4820e44 | 524 | return __sclp_vt220_write(&ch, 1, 0, 0, 1); |
1da177e4 LT |
525 | } |
526 | ||
527 | /* | |
528 | * This routine is called by the kernel after it has written a | |
529 | * series of characters to the tty device using put_char(). | |
530 | */ | |
531 | static void | |
532 | sclp_vt220_flush_chars(struct tty_struct *tty) | |
533 | { | |
534 | if (sclp_vt220_outqueue_count == 0) | |
535 | sclp_vt220_emit_current(); | |
536 | else | |
537 | sclp_vt220_flush_later = 1; | |
538 | } | |
539 | ||
540 | /* | |
541 | * This routine returns the numbers of characters the tty driver | |
542 | * will accept for queuing to be written. This number is subject | |
543 | * to change as output buffers get emptied, or if the output flow | |
544 | * control is acted. | |
545 | */ | |
546 | static int | |
547 | sclp_vt220_write_room(struct tty_struct *tty) | |
548 | { | |
549 | unsigned long flags; | |
550 | struct list_head *l; | |
551 | int count; | |
552 | ||
553 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
554 | count = 0; | |
555 | if (sclp_vt220_current_request != NULL) | |
556 | count = sclp_vt220_space_left(sclp_vt220_current_request); | |
557 | list_for_each(l, &sclp_vt220_empty) | |
558 | count += SCLP_VT220_MAX_CHARS_PER_BUFFER; | |
559 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
560 | return count; | |
561 | } | |
562 | ||
563 | /* | |
564 | * Return number of buffered chars. | |
565 | */ | |
566 | static int | |
567 | sclp_vt220_chars_in_buffer(struct tty_struct *tty) | |
568 | { | |
569 | unsigned long flags; | |
570 | struct list_head *l; | |
571 | struct sclp_vt220_request *r; | |
572 | int count; | |
573 | ||
574 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
575 | count = 0; | |
576 | if (sclp_vt220_current_request != NULL) | |
577 | count = sclp_vt220_chars_stored(sclp_vt220_current_request); | |
578 | list_for_each(l, &sclp_vt220_outqueue) { | |
579 | r = list_entry(l, struct sclp_vt220_request, list); | |
580 | count += sclp_vt220_chars_stored(r); | |
581 | } | |
582 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
583 | return count; | |
584 | } | |
585 | ||
586 | static void | |
587 | __sclp_vt220_flush_buffer(void) | |
588 | { | |
589 | unsigned long flags; | |
590 | ||
591 | sclp_vt220_emit_current(); | |
592 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
593 | if (timer_pending(&sclp_vt220_timer)) | |
594 | del_timer(&sclp_vt220_timer); | |
595 | while (sclp_vt220_outqueue_count > 0) { | |
596 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
597 | sclp_sync_wait(); | |
598 | spin_lock_irqsave(&sclp_vt220_lock, flags); | |
599 | } | |
600 | spin_unlock_irqrestore(&sclp_vt220_lock, flags); | |
601 | } | |
602 | ||
603 | /* | |
604 | * Pass on all buffers to the hardware. Return only when there are no more | |
605 | * buffers pending. | |
606 | */ | |
607 | static void | |
608 | sclp_vt220_flush_buffer(struct tty_struct *tty) | |
609 | { | |
610 | sclp_vt220_emit_current(); | |
611 | } | |
612 | ||
ad211790 PO |
613 | /* Release allocated pages. */ |
614 | static void __init __sclp_vt220_free_pages(void) | |
5aaaf9f0 HC |
615 | { |
616 | struct list_head *page, *p; | |
617 | ||
618 | list_for_each_safe(page, p, &sclp_vt220_empty) { | |
619 | list_del(page); | |
620 | if (slab_is_available()) | |
621 | free_page((unsigned long) page); | |
622 | else | |
623 | free_bootmem((unsigned long) page, PAGE_SIZE); | |
624 | } | |
625 | } | |
626 | ||
ad211790 PO |
627 | /* Release memory and unregister from sclp core. Controlled by init counting - |
628 | * only the last invoker will actually perform these actions. */ | |
629 | static void __init __sclp_vt220_cleanup(void) | |
630 | { | |
631 | sclp_vt220_init_count--; | |
632 | if (sclp_vt220_init_count != 0) | |
633 | return; | |
634 | sclp_unregister(&sclp_vt220_register); | |
635 | __sclp_vt220_free_pages(); | |
636 | } | |
637 | ||
638 | /* Allocate buffer pages and register with sclp core. Controlled by init | |
639 | * counting - only the first invoker will actually perform these actions. */ | |
640 | static int __init __sclp_vt220_init(int num_pages) | |
1da177e4 LT |
641 | { |
642 | void *page; | |
643 | int i; | |
59eb1ca7 | 644 | int rc; |
1da177e4 | 645 | |
ad211790 PO |
646 | sclp_vt220_init_count++; |
647 | if (sclp_vt220_init_count != 1) | |
1da177e4 | 648 | return 0; |
1da177e4 LT |
649 | spin_lock_init(&sclp_vt220_lock); |
650 | INIT_LIST_HEAD(&sclp_vt220_empty); | |
651 | INIT_LIST_HEAD(&sclp_vt220_outqueue); | |
1da177e4 LT |
652 | init_timer(&sclp_vt220_timer); |
653 | sclp_vt220_current_request = NULL; | |
654 | sclp_vt220_buffered_chars = 0; | |
655 | sclp_vt220_outqueue_count = 0; | |
656 | sclp_vt220_tty = NULL; | |
657 | sclp_vt220_flush_later = 0; | |
658 | ||
659 | /* Allocate pages for output buffering */ | |
5aaaf9f0 HC |
660 | for (i = 0; i < num_pages; i++) { |
661 | if (slab_is_available()) | |
1da177e4 | 662 | page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); |
5aaaf9f0 HC |
663 | else |
664 | page = alloc_bootmem_low_pages(PAGE_SIZE); | |
665 | if (!page) { | |
ad211790 PO |
666 | rc = -ENOMEM; |
667 | goto out; | |
5aaaf9f0 | 668 | } |
1da177e4 LT |
669 | list_add_tail((struct list_head *) page, &sclp_vt220_empty); |
670 | } | |
59eb1ca7 | 671 | rc = sclp_register(&sclp_vt220_register); |
ad211790 | 672 | out: |
59eb1ca7 | 673 | if (rc) { |
ad211790 PO |
674 | __sclp_vt220_free_pages(); |
675 | sclp_vt220_init_count--; | |
59eb1ca7 CB |
676 | } |
677 | return rc; | |
1da177e4 LT |
678 | } |
679 | ||
b68e31d0 | 680 | static const struct tty_operations sclp_vt220_ops = { |
1da177e4 LT |
681 | .open = sclp_vt220_open, |
682 | .close = sclp_vt220_close, | |
683 | .write = sclp_vt220_write, | |
684 | .put_char = sclp_vt220_put_char, | |
685 | .flush_chars = sclp_vt220_flush_chars, | |
686 | .write_room = sclp_vt220_write_room, | |
687 | .chars_in_buffer = sclp_vt220_chars_in_buffer, | |
5aaaf9f0 | 688 | .flush_buffer = sclp_vt220_flush_buffer, |
1da177e4 LT |
689 | }; |
690 | ||
691 | /* | |
692 | * Register driver with SCLP and Linux and initialize internal tty structures. | |
693 | */ | |
5aaaf9f0 | 694 | static int __init sclp_vt220_tty_init(void) |
1da177e4 LT |
695 | { |
696 | struct tty_driver *driver; | |
697 | int rc; | |
698 | ||
699 | /* Note: we're not testing for CONSOLE_IS_SCLP here to preserve | |
700 | * symmetry between VM and LPAR systems regarding ttyS1. */ | |
701 | driver = alloc_tty_driver(1); | |
702 | if (!driver) | |
703 | return -ENOMEM; | |
ad211790 | 704 | rc = __sclp_vt220_init(MAX_KMEM_PAGES); |
5aaaf9f0 HC |
705 | if (rc) |
706 | goto out_driver; | |
1da177e4 LT |
707 | |
708 | driver->owner = THIS_MODULE; | |
709 | driver->driver_name = SCLP_VT220_DRIVER_NAME; | |
710 | driver->name = SCLP_VT220_DEVICE_NAME; | |
711 | driver->major = SCLP_VT220_MAJOR; | |
712 | driver->minor_start = SCLP_VT220_MINOR; | |
713 | driver->type = TTY_DRIVER_TYPE_SYSTEM; | |
714 | driver->subtype = SYSTEM_TYPE_TTY; | |
715 | driver->init_termios = tty_std_termios; | |
716 | driver->flags = TTY_DRIVER_REAL_RAW; | |
717 | tty_set_operations(driver, &sclp_vt220_ops); | |
718 | ||
719 | rc = tty_register_driver(driver); | |
a12c53f4 | 720 | if (rc) |
59eb1ca7 | 721 | goto out_init; |
1da177e4 LT |
722 | sclp_vt220_driver = driver; |
723 | return 0; | |
1da177e4 | 724 | |
5aaaf9f0 | 725 | out_init: |
ad211790 | 726 | __sclp_vt220_cleanup(); |
5aaaf9f0 HC |
727 | out_driver: |
728 | put_tty_driver(driver); | |
729 | return rc; | |
730 | } | |
731 | __initcall(sclp_vt220_tty_init); | |
1da177e4 LT |
732 | |
733 | #ifdef CONFIG_SCLP_VT220_CONSOLE | |
734 | ||
735 | static void | |
736 | sclp_vt220_con_write(struct console *con, const char *buf, unsigned int count) | |
737 | { | |
d1e23375 | 738 | __sclp_vt220_write((const unsigned char *) buf, count, 1, 1, 0); |
1da177e4 LT |
739 | } |
740 | ||
741 | static struct tty_driver * | |
742 | sclp_vt220_con_device(struct console *c, int *index) | |
743 | { | |
744 | *index = 0; | |
745 | return sclp_vt220_driver; | |
746 | } | |
747 | ||
2332ce1a HS |
748 | static int |
749 | sclp_vt220_notify(struct notifier_block *self, | |
750 | unsigned long event, void *data) | |
1da177e4 LT |
751 | { |
752 | __sclp_vt220_flush_buffer(); | |
2332ce1a | 753 | return NOTIFY_OK; |
1da177e4 LT |
754 | } |
755 | ||
2332ce1a HS |
756 | static struct notifier_block on_panic_nb = { |
757 | .notifier_call = sclp_vt220_notify, | |
758 | .priority = 1, | |
759 | }; | |
760 | ||
761 | static struct notifier_block on_reboot_nb = { | |
762 | .notifier_call = sclp_vt220_notify, | |
763 | .priority = 1, | |
764 | }; | |
765 | ||
1da177e4 LT |
766 | /* Structure needed to register with printk */ |
767 | static struct console sclp_vt220_console = | |
768 | { | |
769 | .name = SCLP_VT220_CONSOLE_NAME, | |
770 | .write = sclp_vt220_con_write, | |
771 | .device = sclp_vt220_con_device, | |
1da177e4 LT |
772 | .flags = CON_PRINTBUFFER, |
773 | .index = SCLP_VT220_CONSOLE_INDEX | |
774 | }; | |
775 | ||
776 | static int __init | |
777 | sclp_vt220_con_init(void) | |
778 | { | |
779 | int rc; | |
780 | ||
781 | if (!CONSOLE_IS_SCLP) | |
782 | return 0; | |
ad211790 | 783 | rc = __sclp_vt220_init(MAX_CONSOLE_PAGES); |
1da177e4 LT |
784 | if (rc) |
785 | return rc; | |
786 | /* Attach linux console */ | |
2332ce1a HS |
787 | atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb); |
788 | register_reboot_notifier(&on_reboot_nb); | |
1da177e4 LT |
789 | register_console(&sclp_vt220_console); |
790 | return 0; | |
791 | } | |
792 | ||
793 | console_initcall(sclp_vt220_con_init); | |
794 | #endif /* CONFIG_SCLP_VT220_CONSOLE */ | |
795 |