1// SPDX-License-Identifier: GPL-2.0
2/*
3 * IBM/3270 Driver - core functions.
4 *
5 * Author(s):
6 *   Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
7 *   Rewritten for 2.5 by Martin Schwidefsky <schwidefsky@de.ibm.com>
8 *     Copyright IBM Corp. 2003, 2009
9 */
10
11#include <linux/module.h>
12#include <linux/err.h>
13#include <linux/init.h>
14#include <linux/interrupt.h>
15#include <linux/list.h>
16#include <linux/slab.h>
17#include <linux/types.h>
18#include <linux/wait.h>
19
20#include <asm/ccwdev.h>
21#include <asm/cio.h>
22#include <asm/ebcdic.h>
23#include <asm/diag.h>
24
25#include "raw3270.h"
26
27#include <linux/major.h>
28#include <linux/kdev_t.h>
29#include <linux/device.h>
30#include <linux/mutex.h>
31
32struct class *class3270;
33EXPORT_SYMBOL(class3270);
34
35/* The main 3270 data structure. */
36struct raw3270 {
37	struct list_head list;
38	struct ccw_device *cdev;
39	int minor;
40
41	int model, rows, cols;
42	int old_model, old_rows, old_cols;
43	unsigned int state;
44	unsigned long flags;
45
46	struct list_head req_queue;	/* Request queue. */
47	struct list_head view_list;	/* List of available views. */
48	struct raw3270_view *view;	/* Active view. */
49
50	struct timer_list timer;	/* Device timer. */
51
52	unsigned char *ascebc;		/* ascii -> ebcdic table */
53
54	struct raw3270_view init_view;
55	struct raw3270_request init_reset;
56	struct raw3270_request init_readpart;
57	struct raw3270_request init_readmod;
58	unsigned char init_data[256];
59	struct work_struct resize_work;
60};
61
62/* raw3270->state */
63#define RAW3270_STATE_INIT	0	/* Initial state */
64#define RAW3270_STATE_RESET	1	/* Reset command is pending */
65#define RAW3270_STATE_W4ATTN	2	/* Wait for attention interrupt */
66#define RAW3270_STATE_READMOD	3	/* Read partition is pending */
67#define RAW3270_STATE_READY	4	/* Device is usable by views */
68
69/* raw3270->flags */
70#define RAW3270_FLAGS_14BITADDR	0	/* 14-bit buffer addresses */
71#define RAW3270_FLAGS_BUSY	1	/* Device busy, leave it alone */
72#define RAW3270_FLAGS_CONSOLE	2	/* Device is the console. */
73
74/* Semaphore to protect global data of raw3270 (devices, views, etc). */
75static DEFINE_MUTEX(raw3270_mutex);
76
77/* List of 3270 devices. */
78static LIST_HEAD(raw3270_devices);
79
80/*
81 * Flag to indicate if the driver has been registered. Some operations
82 * like waiting for the end of i/o need to be done differently as long
83 * as the kernel is still starting up (console support).
84 */
85static int raw3270_registered;
86
87/* Module parameters */
88static bool tubxcorrect;
89module_param(tubxcorrect, bool, 0);
90
91/*
92 * Wait queue for device init/delete, view delete.
93 */
94DECLARE_WAIT_QUEUE_HEAD(raw3270_wait_queue);
95EXPORT_SYMBOL(raw3270_wait_queue);
96
97static void __raw3270_disconnect(struct raw3270 *rp);
98
99/*
100 * Encode array for 12 bit 3270 addresses.
101 */
102static unsigned char raw3270_ebcgraf[64] =	{
103	0x40, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
104	0xc8, 0xc9, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
105	0x50, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
106	0xd8, 0xd9, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
107	0x60, 0x61, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
108	0xe8, 0xe9, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
109	0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
110	0xf8, 0xf9, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f
111};
112
113static inline int raw3270_state_ready(struct raw3270 *rp)
114{
115	return rp->state == RAW3270_STATE_READY;
116}
117
118void raw3270_buffer_address(struct raw3270 *rp, char *cp, int x, int y)
119{
120	int addr;
121
122	if (x < 0)
123		x = max_t(int, 0, rp->view->cols + x);
124	if (y < 0)
125		y = max_t(int, 0, rp->view->rows + y);
126	addr = (y * rp->view->cols) + x;
127	if (test_bit(RAW3270_FLAGS_14BITADDR, &rp->flags)) {
128		cp[0] = (addr >> 8) & 0x3f;
129		cp[1] = addr & 0xff;
130	} else {
131		cp[0] = raw3270_ebcgraf[(addr >> 6) & 0x3f];
132		cp[1] = raw3270_ebcgraf[addr & 0x3f];
133	}
134}
135EXPORT_SYMBOL(raw3270_buffer_address);
136
137/*
138 * Allocate a new 3270 ccw request
139 */
140struct raw3270_request *raw3270_request_alloc(size_t size)
141{
142	struct raw3270_request *rq;
143
144	/* Allocate request structure */
145	rq = kzalloc(sizeof(*rq), GFP_KERNEL | GFP_DMA);
146	if (!rq)
147		return ERR_PTR(-ENOMEM);
148
149	/* alloc output buffer. */
150	if (size > 0) {
151		rq->buffer = kmalloc(size, GFP_KERNEL | GFP_DMA);
152		if (!rq->buffer) {
153			kfree(rq);
154			return ERR_PTR(-ENOMEM);
155		}
156	}
157	rq->size = size;
158	INIT_LIST_HEAD(&rq->list);
159
160	/*
161	 * Setup ccw.
162	 */
163	rq->ccw.cda = __pa(rq->buffer);
164	rq->ccw.flags = CCW_FLAG_SLI;
165
166	return rq;
167}
168EXPORT_SYMBOL(raw3270_request_alloc);
169
170/*
171 * Free 3270 ccw request
172 */
173void raw3270_request_free(struct raw3270_request *rq)
174{
175	kfree(rq->buffer);
176	kfree(rq);
177}
178EXPORT_SYMBOL(raw3270_request_free);
179
180/*
181 * Reset request to initial state.
182 */
183int raw3270_request_reset(struct raw3270_request *rq)
184{
185	if (WARN_ON_ONCE(!list_empty(&rq->list)))
186		return -EBUSY;
187	rq->ccw.cmd_code = 0;
188	rq->ccw.count = 0;
189	rq->ccw.cda = __pa(rq->buffer);
190	rq->ccw.flags = CCW_FLAG_SLI;
191	rq->rescnt = 0;
192	rq->rc = 0;
193	return 0;
194}
195EXPORT_SYMBOL(raw3270_request_reset);
196
197/*
198 * Set command code to ccw of a request.
199 */
200void raw3270_request_set_cmd(struct raw3270_request *rq, u8 cmd)
201{
202	rq->ccw.cmd_code = cmd;
203}
204EXPORT_SYMBOL(raw3270_request_set_cmd);
205
206/*
207 * Add data fragment to output buffer.
208 */
209int raw3270_request_add_data(struct raw3270_request *rq, void *data, size_t size)
210{
211	if (size + rq->ccw.count > rq->size)
212		return -E2BIG;
213	memcpy(rq->buffer + rq->ccw.count, data, size);
214	rq->ccw.count += size;
215	return 0;
216}
217EXPORT_SYMBOL(raw3270_request_add_data);
218
219/*
220 * Set address/length pair to ccw of a request.
221 */
222void raw3270_request_set_data(struct raw3270_request *rq, void *data, size_t size)
223{
224	rq->ccw.cda = __pa(data);
225	rq->ccw.count = size;
226}
227EXPORT_SYMBOL(raw3270_request_set_data);
228
229/*
230 * Set idal buffer to ccw of a request.
231 */
232void raw3270_request_set_idal(struct raw3270_request *rq, struct idal_buffer *ib)
233{
234	rq->ccw.cda = __pa(ib->data);
235	rq->ccw.count = ib->size;
236	rq->ccw.flags |= CCW_FLAG_IDA;
237}
238EXPORT_SYMBOL(raw3270_request_set_idal);
239
240/*
241 * Add the request to the request queue, try to start it if the
242 * 3270 device is idle. Return without waiting for end of i/o.
243 */
244static int __raw3270_start(struct raw3270 *rp, struct raw3270_view *view,
245			   struct raw3270_request *rq)
246{
247	rq->view = view;
248	raw3270_get_view(view);
249	if (list_empty(&rp->req_queue) &&
250	    !test_bit(RAW3270_FLAGS_BUSY, &rp->flags)) {
251		/* No other requests are on the queue. Start this one. */
252		rq->rc = ccw_device_start(rp->cdev, &rq->ccw,
253					  (unsigned long)rq, 0, 0);
254		if (rq->rc) {
255			raw3270_put_view(view);
256			return rq->rc;
257		}
258	}
259	list_add_tail(&rq->list, &rp->req_queue);
260	return 0;
261}
262
263int raw3270_view_active(struct raw3270_view *view)
264{
265	struct raw3270 *rp = view->dev;
266
267	return rp && rp->view == view;
268}
269
270int raw3270_start(struct raw3270_view *view, struct raw3270_request *rq)
271{
272	unsigned long flags;
273	struct raw3270 *rp;
274	int rc;
275
276	spin_lock_irqsave(get_ccwdev_lock(view->dev->cdev), flags);
277	rp = view->dev;
278	if (!rp || rp->view != view)
279		rc = -EACCES;
280	else if (!raw3270_state_ready(rp))
281		rc = -EBUSY;
282	else
283		rc =  __raw3270_start(rp, view, rq);
284	spin_unlock_irqrestore(get_ccwdev_lock(view->dev->cdev), flags);
285	return rc;
286}
287EXPORT_SYMBOL(raw3270_start);
288
289int raw3270_start_request(struct raw3270_view *view, struct raw3270_request *rq,
290			  int cmd, void *data, size_t len)
291{
292	int rc;
293
294	rc = raw3270_request_reset(rq);
295	if (rc)
296		return rc;
297	raw3270_request_set_cmd(rq, cmd);
298	rc = raw3270_request_add_data(rq, data, len);
299	if (rc)
300		return rc;
301	return raw3270_start(view, rq);
302}
303EXPORT_SYMBOL(raw3270_start_request);
304
305int raw3270_start_locked(struct raw3270_view *view, struct raw3270_request *rq)
306{
307	struct raw3270 *rp;
308	int rc;
309
310	rp = view->dev;
311	if (!rp || rp->view != view)
312		rc = -EACCES;
313	else if (!raw3270_state_ready(rp))
314		rc = -EBUSY;
315	else
316		rc =  __raw3270_start(rp, view, rq);
317	return rc;
318}
319EXPORT_SYMBOL(raw3270_start_locked);
320
321int raw3270_start_irq(struct raw3270_view *view, struct raw3270_request *rq)
322{
323	struct raw3270 *rp;
324
325	rp = view->dev;
326	rq->view = view;
327	raw3270_get_view(view);
328	list_add_tail(&rq->list, &rp->req_queue);
329	return 0;
330}
331EXPORT_SYMBOL(raw3270_start_irq);
332
333/*
334 * 3270 interrupt routine, called from the ccw_device layer
335 */
336static void raw3270_irq(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
337{
338	struct raw3270 *rp;
339	struct raw3270_view *view;
340	struct raw3270_request *rq;
341
342	rp = dev_get_drvdata(&cdev->dev);
343	if (!rp)
344		return;
345	rq = (struct raw3270_request *)intparm;
346	view = rq ? rq->view : rp->view;
347
348	if (!IS_ERR(irb)) {
349		/* Handle CE-DE-UE and subsequent UDE */
350		if (irb->scsw.cmd.dstat & DEV_STAT_DEV_END)
351			clear_bit(RAW3270_FLAGS_BUSY, &rp->flags);
352		if (irb->scsw.cmd.dstat == (DEV_STAT_CHN_END |
353					    DEV_STAT_DEV_END |
354					    DEV_STAT_UNIT_EXCEP))
355			set_bit(RAW3270_FLAGS_BUSY, &rp->flags);
356		/* Handle disconnected devices */
357		if ((irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
358		    (irb->ecw[0] & SNS0_INTERVENTION_REQ)) {
359			set_bit(RAW3270_FLAGS_BUSY, &rp->flags);
360			if (rp->state > RAW3270_STATE_RESET)
361				__raw3270_disconnect(rp);
362		}
363		/* Call interrupt handler of the view */
364		if (view)
365			view->fn->intv(view, rq, irb);
366	}
367
368	if (test_bit(RAW3270_FLAGS_BUSY, &rp->flags))
369		/* Device busy, do not start I/O */
370		return;
371
372	if (rq && !list_empty(&rq->list)) {
373		/* The request completed, remove from queue and do callback. */
374		list_del_init(&rq->list);
375		if (rq->callback)
376			rq->callback(rq, rq->callback_data);
377		/* Do put_device for get_device in raw3270_start. */
378		raw3270_put_view(view);
379	}
380
381	/*
382	 * Try to start each request on request queue until one is
383	 * started successful.
384	 */
385	while (!list_empty(&rp->req_queue)) {
386		rq = list_entry(rp->req_queue.next, struct raw3270_request, list);
387		rq->rc = ccw_device_start(rp->cdev, &rq->ccw,
388					  (unsigned long)rq, 0, 0);
389		if (rq->rc == 0)
390			break;
391		/* Start failed. Remove request and do callback. */
392		list_del_init(&rq->list);
393		if (rq->callback)
394			rq->callback(rq, rq->callback_data);
395		/* Do put_device for get_device in raw3270_start. */
396		raw3270_put_view(view);
397	}
398}
399
400/*
401 * To determine the size of the 3270 device we need to do:
402 * 1) send a 'read partition' data stream to the device
403 * 2) wait for the attn interrupt that precedes the query reply
404 * 3) do a read modified to get the query reply
405 * To make things worse we have to cope with intervention
406 * required (3270 device switched to 'stand-by') and command
407 * rejects (old devices that can't do 'read partition').
408 */
409struct raw3270_ua {	/* Query Reply structure for Usable Area */
410	struct {	/* Usable Area Query Reply Base */
411		short l;	/* Length of this structured field */
412		char  sfid;	/* 0x81 if Query Reply */
413		char  qcode;	/* 0x81 if Usable Area */
414		char  flags0;
415		char  flags1;
416		short w;	/* Width of usable area */
417		short h;	/* Heigth of usavle area */
418		char  units;	/* 0x00:in; 0x01:mm */
419		int   xr;
420		int   yr;
421		char  aw;
422		char  ah;
423		short buffsz;	/* Character buffer size, bytes */
424		char  xmin;
425		char  ymin;
426		char  xmax;
427		char  ymax;
428	} __packed uab;
429	struct {	/* Alternate Usable Area Self-Defining Parameter */
430		char  l;	/* Length of this Self-Defining Parm */
431		char  sdpid;	/* 0x02 if Alternate Usable Area */
432		char  res;
433		char  auaid;	/* 0x01 is Id for the A U A */
434		short wauai;	/* Width of AUAi */
435		short hauai;	/* Height of AUAi */
436		char  auaunits;	/* 0x00:in, 0x01:mm */
437		int   auaxr;
438		int   auayr;
439		char  awauai;
440		char  ahauai;
441	} __packed aua;
442} __packed;
443
444static void raw3270_size_device_vm(struct raw3270 *rp)
445{
446	int rc, model;
447	struct ccw_dev_id dev_id;
448	struct diag210 diag_data;
449	struct diag8c diag8c_data;
450
451	ccw_device_get_id(rp->cdev, &dev_id);
452	rc = diag8c(&diag8c_data, &dev_id);
453	if (!rc) {
454		rp->model = 2;
455		rp->rows = diag8c_data.height;
456		rp->cols = diag8c_data.width;
457		if (diag8c_data.flags & 1)
458			set_bit(RAW3270_FLAGS_14BITADDR, &rp->flags);
459		return;
460	}
461
462	diag_data.vrdcdvno = dev_id.devno;
463	diag_data.vrdclen = sizeof(struct diag210);
464	rc = diag210(&diag_data);
465	model = diag_data.vrdccrmd;
466	/* Use default model 2 if the size could not be detected */
467	if (rc || model < 2 || model > 5)
468		model = 2;
469	switch (model) {
470	case 2:
471		rp->model = model;
472		rp->rows = 24;
473		rp->cols = 80;
474		break;
475	case 3:
476		rp->model = model;
477		rp->rows = 32;
478		rp->cols = 80;
479		break;
480	case 4:
481		rp->model = model;
482		rp->rows = 43;
483		rp->cols = 80;
484		break;
485	case 5:
486		rp->model = model;
487		rp->rows = 27;
488		rp->cols = 132;
489		break;
490	}
491}
492
493static void raw3270_size_device(struct raw3270 *rp, char *init_data)
494{
495	struct raw3270_ua *uap;
496
497	/* Got a Query Reply */
498	uap = (struct raw3270_ua *)(init_data + 1);
499	/* Paranoia check. */
500	if (init_data[0] != 0x88 || uap->uab.qcode != 0x81) {
501		/* Couldn't detect size. Use default model 2. */
502		rp->model = 2;
503		rp->rows = 24;
504		rp->cols = 80;
505		return;
506	}
507	/* Copy rows/columns of default Usable Area */
508	rp->rows = uap->uab.h;
509	rp->cols = uap->uab.w;
510	/* Check for 14 bit addressing */
511	if ((uap->uab.flags0 & 0x0d) == 0x01)
512		set_bit(RAW3270_FLAGS_14BITADDR, &rp->flags);
513	/* Check for Alternate Usable Area */
514	if (uap->uab.l == sizeof(struct raw3270_ua) &&
515	    uap->aua.sdpid == 0x02) {
516		rp->rows = uap->aua.hauai;
517		rp->cols = uap->aua.wauai;
518	}
519	/* Try to find a model. */
520	rp->model = 0;
521	if (rp->rows == 24 && rp->cols == 80)
522		rp->model = 2;
523	if (rp->rows == 32 && rp->cols == 80)
524		rp->model = 3;
525	if (rp->rows == 43 && rp->cols == 80)
526		rp->model = 4;
527	if (rp->rows == 27 && rp->cols == 132)
528		rp->model = 5;
529}
530
531static void raw3270_resize_work(struct work_struct *work)
532{
533	struct raw3270 *rp = container_of(work, struct raw3270, resize_work);
534	struct raw3270_view *view;
535
536	/* Notify views about new size */
537	list_for_each_entry(view, &rp->view_list, list) {
538		if (view->fn->resize)
539			view->fn->resize(view, rp->model, rp->rows, rp->cols,
540					 rp->old_model, rp->old_rows, rp->old_cols);
541	}
542	rp->old_cols = rp->cols;
543	rp->old_rows = rp->rows;
544	rp->old_model = rp->model;
545	/* Setup processing done, now activate a view */
546	list_for_each_entry(view, &rp->view_list, list) {
547		rp->view = view;
548		if (view->fn->activate(view) == 0)
549			break;
550		rp->view = NULL;
551	}
552}
553
554static void raw3270_size_device_done(struct raw3270 *rp)
555{
556	rp->view = NULL;
557	rp->state = RAW3270_STATE_READY;
558	schedule_work(&rp->resize_work);
559}
560
561void raw3270_read_modified_cb(struct raw3270_request *rq, void *data)
562{
563	struct raw3270 *rp = rq->view->dev;
564
565	raw3270_size_device(rp, data);
566	raw3270_size_device_done(rp);
567}
568EXPORT_SYMBOL(raw3270_read_modified_cb);
569
570static void raw3270_read_modified(struct raw3270 *rp)
571{
572	if (rp->state != RAW3270_STATE_W4ATTN)
573		return;
574	/* Use 'read modified' to get the result of a read partition. */
575	memset(&rp->init_readmod, 0, sizeof(rp->init_readmod));
576	memset(&rp->init_data, 0, sizeof(rp->init_data));
577	rp->init_readmod.ccw.cmd_code = TC_READMOD;
578	rp->init_readmod.ccw.flags = CCW_FLAG_SLI;
579	rp->init_readmod.ccw.count = sizeof(rp->init_data);
580	rp->init_readmod.ccw.cda = (__u32)__pa(rp->init_data);
581	rp->init_readmod.callback = raw3270_read_modified_cb;
582	rp->init_readmod.callback_data = rp->init_data;
583	rp->state = RAW3270_STATE_READMOD;
584	raw3270_start_irq(&rp->init_view, &rp->init_readmod);
585}
586
587static void raw3270_writesf_readpart(struct raw3270 *rp)
588{
589	static const unsigned char wbuf[] = {
590		0x00, 0x07, 0x01, 0xff, 0x03, 0x00, 0x81
591	};
592
593	/* Store 'read partition' data stream to init_data */
594	memset(&rp->init_readpart, 0, sizeof(rp->init_readpart));
595	memset(&rp->init_data, 0, sizeof(rp->init_data));
596	memcpy(&rp->init_data, wbuf, sizeof(wbuf));
597	rp->init_readpart.ccw.cmd_code = TC_WRITESF;
598	rp->init_readpart.ccw.flags = CCW_FLAG_SLI;
599	rp->init_readpart.ccw.count = sizeof(wbuf);
600	rp->init_readpart.ccw.cda = (__u32)__pa(&rp->init_data);
601	rp->state = RAW3270_STATE_W4ATTN;
602	raw3270_start_irq(&rp->init_view, &rp->init_readpart);
603}
604
605/*
606 * Device reset
607 */
608static void raw3270_reset_device_cb(struct raw3270_request *rq, void *data)
609{
610	struct raw3270 *rp = rq->view->dev;
611
612	if (rp->state != RAW3270_STATE_RESET)
613		return;
614	if (rq->rc) {
615		/* Reset command failed. */
616		rp->state = RAW3270_STATE_INIT;
617	} else if (MACHINE_IS_VM) {
618		raw3270_size_device_vm(rp);
619		raw3270_size_device_done(rp);
620	} else {
621		raw3270_writesf_readpart(rp);
622	}
623	memset(&rp->init_reset, 0, sizeof(rp->init_reset));
624}
625
626static int __raw3270_reset_device(struct raw3270 *rp)
627{
628	int rc;
629
630	/* Check if reset is already pending */
631	if (rp->init_reset.view)
632		return -EBUSY;
633	/* Store reset data stream to init_data/init_reset */
634	rp->init_data[0] = TW_KR;
635	rp->init_reset.ccw.cmd_code = TC_EWRITEA;
636	rp->init_reset.ccw.flags = CCW_FLAG_SLI;
637	rp->init_reset.ccw.count = 1;
638	rp->init_reset.ccw.cda = (__u32)__pa(rp->init_data);
639	rp->init_reset.callback = raw3270_reset_device_cb;
640	rc = __raw3270_start(rp, &rp->init_view, &rp->init_reset);
641	if (rc == 0 && rp->state == RAW3270_STATE_INIT)
642		rp->state = RAW3270_STATE_RESET;
643	return rc;
644}
645
646static int raw3270_reset_device(struct raw3270 *rp)
647{
648	unsigned long flags;
649	int rc;
650
651	spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
652	rc = __raw3270_reset_device(rp);
653	spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
654	return rc;
655}
656
657int raw3270_reset(struct raw3270_view *view)
658{
659	struct raw3270 *rp;
660	int rc;
661
662	rp = view->dev;
663	if (!rp || rp->view != view)
664		rc = -EACCES;
665	else if (!raw3270_state_ready(rp))
666		rc = -EBUSY;
667	else
668		rc = raw3270_reset_device(view->dev);
669	return rc;
670}
671EXPORT_SYMBOL(raw3270_reset);
672
673static void __raw3270_disconnect(struct raw3270 *rp)
674{
675	struct raw3270_request *rq;
676	struct raw3270_view *view;
677
678	rp->state = RAW3270_STATE_INIT;
679	rp->view = &rp->init_view;
680	/* Cancel all queued requests */
681	while (!list_empty(&rp->req_queue)) {
682		rq = list_entry(rp->req_queue.next, struct raw3270_request, list);
683		view = rq->view;
684		rq->rc = -EACCES;
685		list_del_init(&rq->list);
686		if (rq->callback)
687			rq->callback(rq, rq->callback_data);
688		raw3270_put_view(view);
689	}
690	/* Start from scratch */
691	__raw3270_reset_device(rp);
692}
693
694static void raw3270_init_irq(struct raw3270_view *view, struct raw3270_request *rq,
695			     struct irb *irb)
696{
697	struct raw3270 *rp;
698
699	if (rq) {
700		if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) {
701			if (irb->ecw[0] & SNS0_CMD_REJECT)
702				rq->rc = -EOPNOTSUPP;
703			else
704				rq->rc = -EIO;
705		}
706	}
707	if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
708		/* Queue read modified after attention interrupt */
709		rp = view->dev;
710		raw3270_read_modified(rp);
711	}
712}
713
714static struct raw3270_fn raw3270_init_fn = {
715	.intv = raw3270_init_irq
716};
717
718/*
719 * Setup new 3270 device.
720 */
721static int raw3270_setup_device(struct ccw_device *cdev, struct raw3270 *rp,
722				char *ascebc)
723{
724	struct list_head *l;
725	struct raw3270 *tmp;
726	int minor;
727
728	memset(rp, 0, sizeof(struct raw3270));
729	/* Copy ebcdic -> ascii translation table. */
730	memcpy(ascebc, _ascebc, 256);
731	if (tubxcorrect) {
732		/* correct brackets and circumflex */
733		ascebc['['] = 0xad;
734		ascebc[']'] = 0xbd;
735		ascebc['^'] = 0xb0;
736	}
737	rp->ascebc = ascebc;
738
739	/* Set defaults. */
740	rp->rows = 24;
741	rp->cols = 80;
742	rp->old_rows = rp->rows;
743	rp->old_cols = rp->cols;
744
745	INIT_LIST_HEAD(&rp->req_queue);
746	INIT_LIST_HEAD(&rp->view_list);
747
748	rp->init_view.dev = rp;
749	rp->init_view.fn = &raw3270_init_fn;
750	rp->view = &rp->init_view;
751	INIT_WORK(&rp->resize_work, raw3270_resize_work);
752
753	/*
754	 * Add device to list and find the smallest unused minor
755	 * number for it. Note: there is no device with minor 0,
756	 * see special case for fs3270.c:fs3270_open().
757	 */
758	mutex_lock(&raw3270_mutex);
759	/* Keep the list sorted. */
760	minor = RAW3270_FIRSTMINOR;
761	rp->minor = -1;
762	list_for_each(l, &raw3270_devices) {
763		tmp = list_entry(l, struct raw3270, list);
764		if (tmp->minor > minor) {
765			rp->minor = minor;
766			__list_add(&rp->list, l->prev, l);
767			break;
768		}
769		minor++;
770	}
771	if (rp->minor == -1 && minor < RAW3270_MAXDEVS + RAW3270_FIRSTMINOR) {
772		rp->minor = minor;
773		list_add_tail(&rp->list, &raw3270_devices);
774	}
775	mutex_unlock(&raw3270_mutex);
776	/* No free minor number? Then give up. */
777	if (rp->minor == -1)
778		return -EUSERS;
779	rp->cdev = cdev;
780	dev_set_drvdata(&cdev->dev, rp);
781	cdev->handler = raw3270_irq;
782	return 0;
783}
784
785#ifdef CONFIG_TN3270_CONSOLE
786/* Tentative definition - see below for actual definition. */
787static struct ccw_driver raw3270_ccw_driver;
788
789static inline int raw3270_state_final(struct raw3270 *rp)
790{
791	return rp->state == RAW3270_STATE_INIT ||
792		rp->state == RAW3270_STATE_READY;
793}
794
795/*
796 * Setup 3270 device configured as console.
797 */
798struct raw3270 __init *raw3270_setup_console(void)
799{
800	struct ccw_device *cdev;
801	unsigned long flags;
802	struct raw3270 *rp;
803	char *ascebc;
804	int rc;
805
806	cdev = ccw_device_create_console(&raw3270_ccw_driver);
807	if (IS_ERR(cdev))
808		return ERR_CAST(cdev);
809
810	rp = kzalloc(sizeof(*rp), GFP_KERNEL | GFP_DMA);
811	ascebc = kzalloc(256, GFP_KERNEL);
812	rc = raw3270_setup_device(cdev, rp, ascebc);
813	if (rc)
814		return ERR_PTR(rc);
815	set_bit(RAW3270_FLAGS_CONSOLE, &rp->flags);
816
817	rc = ccw_device_enable_console(cdev);
818	if (rc) {
819		ccw_device_destroy_console(cdev);
820		return ERR_PTR(rc);
821	}
822
823	spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
824	do {
825		__raw3270_reset_device(rp);
826		while (!raw3270_state_final(rp)) {
827			ccw_device_wait_idle(rp->cdev);
828			barrier();
829		}
830	} while (rp->state != RAW3270_STATE_READY);
831	spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
832	return rp;
833}
834
835void raw3270_wait_cons_dev(struct raw3270 *rp)
836{
837	unsigned long flags;
838
839	spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
840	ccw_device_wait_idle(rp->cdev);
841	spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
842}
843
844#endif
845
846/*
847 * Create a 3270 device structure.
848 */
849static struct raw3270 *raw3270_create_device(struct ccw_device *cdev)
850{
851	struct raw3270 *rp;
852	char *ascebc;
853	int rc;
854
855	rp = kzalloc(sizeof(*rp), GFP_KERNEL | GFP_DMA);
856	if (!rp)
857		return ERR_PTR(-ENOMEM);
858	ascebc = kmalloc(256, GFP_KERNEL);
859	if (!ascebc) {
860		kfree(rp);
861		return ERR_PTR(-ENOMEM);
862	}
863	rc = raw3270_setup_device(cdev, rp, ascebc);
864	if (rc) {
865		kfree(rp->ascebc);
866		kfree(rp);
867		rp = ERR_PTR(rc);
868	}
869	/* Get reference to ccw_device structure. */
870	get_device(&cdev->dev);
871	return rp;
872}
873
874/*
875 * This helper just validates that it is safe to activate a
876 * view in the panic() context, due to locking restrictions.
877 */
878int raw3270_view_lock_unavailable(struct raw3270_view *view)
879{
880	struct raw3270 *rp = view->dev;
881
882	if (!rp)
883		return -ENODEV;
884	if (spin_is_locked(get_ccwdev_lock(rp->cdev)))
885		return -EBUSY;
886	return 0;
887}
888
889static int raw3270_assign_activate_view(struct raw3270 *rp, struct raw3270_view *view)
890{
891	rp->view = view;
892	return view->fn->activate(view);
893}
894
895static int __raw3270_activate_view(struct raw3270 *rp, struct raw3270_view *view)
896{
897	struct raw3270_view *oldview = NULL, *nv;
898	int rc;
899
900	if (rp->view == view)
901		return 0;
902
903	if (!raw3270_state_ready(rp))
904		return -EBUSY;
905
906	if (rp->view && rp->view->fn->deactivate) {
907		oldview = rp->view;
908		oldview->fn->deactivate(oldview);
909	}
910
911	rc = raw3270_assign_activate_view(rp, view);
912	if (!rc)
913		return 0;
914
915	/* Didn't work. Try to reactivate the old view. */
916	if (oldview) {
917		rc = raw3270_assign_activate_view(rp, oldview);
918		if (!rc)
919			return 0;
920	}
921
922	/* Didn't work as well. Try any other view. */
923	list_for_each_entry(nv, &rp->view_list, list) {
924		if (nv == view || nv == oldview)
925			continue;
926		rc = raw3270_assign_activate_view(rp, nv);
927		if (!rc)
928			break;
929		rp->view = NULL;
930	}
931	return rc;
932}
933
934/*
935 * Activate a view.
936 */
937int raw3270_activate_view(struct raw3270_view *view)
938{
939	struct raw3270 *rp;
940	unsigned long flags;
941	int rc;
942
943	rp = view->dev;
944	if (!rp)
945		return -ENODEV;
946	spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
947	rc = __raw3270_activate_view(rp, view);
948	spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
949	return rc;
950}
951EXPORT_SYMBOL(raw3270_activate_view);
952
953/*
954 * Deactivate current view.
955 */
956void raw3270_deactivate_view(struct raw3270_view *view)
957{
958	unsigned long flags;
959	struct raw3270 *rp;
960
961	rp = view->dev;
962	if (!rp)
963		return;
964	spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
965	if (rp->view == view) {
966		view->fn->deactivate(view);
967		rp->view = NULL;
968		/* Move deactivated view to end of list. */
969		list_del_init(&view->list);
970		list_add_tail(&view->list, &rp->view_list);
971		/* Try to activate another view. */
972		if (raw3270_state_ready(rp)) {
973			list_for_each_entry(view, &rp->view_list, list) {
974				rp->view = view;
975				if (view->fn->activate(view) == 0)
976					break;
977				rp->view = NULL;
978			}
979		}
980	}
981	spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
982}
983EXPORT_SYMBOL(raw3270_deactivate_view);
984
985/*
986 * Add view to device with minor "minor".
987 */
988int raw3270_add_view(struct raw3270_view *view, struct raw3270_fn *fn,
989		     int minor, int subclass)
990{
991	unsigned long flags;
992	struct raw3270 *rp;
993	int rc;
994
995	if (minor <= 0)
996		return -ENODEV;
997	mutex_lock(&raw3270_mutex);
998	rc = -ENODEV;
999	list_for_each_entry(rp, &raw3270_devices, list) {
1000		if (rp->minor != minor)
1001			continue;
1002		spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
1003		atomic_set(&view->ref_count, 2);
1004		view->dev = rp;
1005		view->fn = fn;
1006		view->model = rp->model;
1007		view->rows = rp->rows;
1008		view->cols = rp->cols;
1009		view->ascebc = rp->ascebc;
1010		spin_lock_init(&view->lock);
1011		lockdep_set_subclass(&view->lock, subclass);
1012		list_add(&view->list, &rp->view_list);
1013		rc = 0;
1014		spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
1015		break;
1016	}
1017	mutex_unlock(&raw3270_mutex);
1018	return rc;
1019}
1020EXPORT_SYMBOL(raw3270_add_view);
1021
1022/*
1023 * Find specific view of device with minor "minor".
1024 */
1025struct raw3270_view *raw3270_find_view(struct raw3270_fn *fn, int minor)
1026{
1027	struct raw3270 *rp;
1028	struct raw3270_view *view, *tmp;
1029	unsigned long flags;
1030
1031	mutex_lock(&raw3270_mutex);
1032	view = ERR_PTR(-ENODEV);
1033	list_for_each_entry(rp, &raw3270_devices, list) {
1034		if (rp->minor != minor)
1035			continue;
1036		spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
1037		list_for_each_entry(tmp, &rp->view_list, list) {
1038			if (tmp->fn == fn) {
1039				raw3270_get_view(tmp);
1040				view = tmp;
1041				break;
1042			}
1043		}
1044		spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
1045		break;
1046	}
1047	mutex_unlock(&raw3270_mutex);
1048	return view;
1049}
1050EXPORT_SYMBOL(raw3270_find_view);
1051
1052/*
1053 * Remove view from device and free view structure via call to view->fn->free.
1054 */
1055void raw3270_del_view(struct raw3270_view *view)
1056{
1057	unsigned long flags;
1058	struct raw3270 *rp;
1059	struct raw3270_view *nv;
1060
1061	rp = view->dev;
1062	spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
1063	if (rp->view == view) {
1064		view->fn->deactivate(view);
1065		rp->view = NULL;
1066	}
1067	list_del_init(&view->list);
1068	if (!rp->view && raw3270_state_ready(rp)) {
1069		/* Try to activate another view. */
1070		list_for_each_entry(nv, &rp->view_list, list) {
1071			if (nv->fn->activate(nv) == 0) {
1072				rp->view = nv;
1073				break;
1074			}
1075		}
1076	}
1077	spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
1078	/* Wait for reference counter to drop to zero. */
1079	atomic_dec(&view->ref_count);
1080	wait_event(raw3270_wait_queue, atomic_read(&view->ref_count) == 0);
1081	if (view->fn->free)
1082		view->fn->free(view);
1083}
1084EXPORT_SYMBOL(raw3270_del_view);
1085
1086/*
1087 * Remove a 3270 device structure.
1088 */
1089static void raw3270_delete_device(struct raw3270 *rp)
1090{
1091	struct ccw_device *cdev;
1092
1093	/* Remove from device chain. */
1094	mutex_lock(&raw3270_mutex);
1095	list_del_init(&rp->list);
1096	mutex_unlock(&raw3270_mutex);
1097
1098	/* Disconnect from ccw_device. */
1099	cdev = rp->cdev;
1100	rp->cdev = NULL;
1101	dev_set_drvdata(&cdev->dev, NULL);
1102	cdev->handler = NULL;
1103
1104	/* Put ccw_device structure. */
1105	put_device(&cdev->dev);
1106
1107	/* Now free raw3270 structure. */
1108	kfree(rp->ascebc);
1109	kfree(rp);
1110}
1111
1112static int raw3270_probe(struct ccw_device *cdev)
1113{
1114	return 0;
1115}
1116
1117/*
1118 * Additional attributes for a 3270 device
1119 */
1120static ssize_t model_show(struct device *dev, struct device_attribute *attr,
1121			  char *buf)
1122{
1123	return sysfs_emit(buf, "%i\n",
1124			  ((struct raw3270 *)dev_get_drvdata(dev))->model);
1125}
1126static DEVICE_ATTR_RO(model);
1127
1128static ssize_t rows_show(struct device *dev, struct device_attribute *attr,
1129			 char *buf)
1130{
1131	return sysfs_emit(buf, "%i\n",
1132			  ((struct raw3270 *)dev_get_drvdata(dev))->rows);
1133}
1134static DEVICE_ATTR_RO(rows);
1135
1136static ssize_t
1137columns_show(struct device *dev, struct device_attribute *attr,
1138	     char *buf)
1139{
1140	return sysfs_emit(buf, "%i\n",
1141			  ((struct raw3270 *)dev_get_drvdata(dev))->cols);
1142}
1143static DEVICE_ATTR_RO(columns);
1144
1145static struct attribute *raw3270_attrs[] = {
1146	&dev_attr_model.attr,
1147	&dev_attr_rows.attr,
1148	&dev_attr_columns.attr,
1149	NULL,
1150};
1151
1152static const struct attribute_group raw3270_attr_group = {
1153	.attrs = raw3270_attrs,
1154};
1155
1156static int raw3270_create_attributes(struct raw3270 *rp)
1157{
1158	return sysfs_create_group(&rp->cdev->dev.kobj, &raw3270_attr_group);
1159}
1160
1161/*
1162 * Notifier for device addition/removal
1163 */
1164static LIST_HEAD(raw3270_notifier);
1165
1166int raw3270_register_notifier(struct raw3270_notifier *notifier)
1167{
1168	struct raw3270 *rp;
1169
1170	mutex_lock(&raw3270_mutex);
1171	list_add_tail(&notifier->list, &raw3270_notifier);
1172	list_for_each_entry(rp, &raw3270_devices, list)
1173		notifier->create(rp->minor);
1174	mutex_unlock(&raw3270_mutex);
1175	return 0;
1176}
1177EXPORT_SYMBOL(raw3270_register_notifier);
1178
1179void raw3270_unregister_notifier(struct raw3270_notifier *notifier)
1180{
1181	struct raw3270 *rp;
1182
1183	mutex_lock(&raw3270_mutex);
1184	list_for_each_entry(rp, &raw3270_devices, list)
1185		notifier->destroy(rp->minor);
1186	list_del(&notifier->list);
1187	mutex_unlock(&raw3270_mutex);
1188}
1189EXPORT_SYMBOL(raw3270_unregister_notifier);
1190
1191/*
1192 * Set 3270 device online.
1193 */
1194static int raw3270_set_online(struct ccw_device *cdev)
1195{
1196	struct raw3270_notifier *np;
1197	struct raw3270 *rp;
1198	int rc;
1199
1200	rp = raw3270_create_device(cdev);
1201	if (IS_ERR(rp))
1202		return PTR_ERR(rp);
1203	rc = raw3270_create_attributes(rp);
1204	if (rc)
1205		goto failure;
1206	raw3270_reset_device(rp);
1207	mutex_lock(&raw3270_mutex);
1208	list_for_each_entry(np, &raw3270_notifier, list)
1209		np->create(rp->minor);
1210	mutex_unlock(&raw3270_mutex);
1211	return 0;
1212
1213failure:
1214	raw3270_delete_device(rp);
1215	return rc;
1216}
1217
1218/*
1219 * Remove 3270 device structure.
1220 */
1221static void raw3270_remove(struct ccw_device *cdev)
1222{
1223	unsigned long flags;
1224	struct raw3270 *rp;
1225	struct raw3270_view *v;
1226	struct raw3270_notifier *np;
1227
1228	rp = dev_get_drvdata(&cdev->dev);
1229	/*
1230	 * _remove is the opposite of _probe; it's probe that
1231	 * should set up rp.  raw3270_remove gets entered for
1232	 * devices even if they haven't been varied online.
1233	 * Thus, rp may validly be NULL here.
1234	 */
1235	if (!rp)
1236		return;
1237
1238	sysfs_remove_group(&cdev->dev.kobj, &raw3270_attr_group);
1239
1240	/* Deactivate current view and remove all views. */
1241	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1242	if (rp->view) {
1243		if (rp->view->fn->deactivate)
1244			rp->view->fn->deactivate(rp->view);
1245		rp->view = NULL;
1246	}
1247	while (!list_empty(&rp->view_list)) {
1248		v = list_entry(rp->view_list.next, struct raw3270_view, list);
1249		if (v->fn->release)
1250			v->fn->release(v);
1251		spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1252		raw3270_del_view(v);
1253		spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1254	}
1255	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1256
1257	mutex_lock(&raw3270_mutex);
1258	list_for_each_entry(np, &raw3270_notifier, list)
1259		np->destroy(rp->minor);
1260	mutex_unlock(&raw3270_mutex);
1261
1262	/* Reset 3270 device. */
1263	raw3270_reset_device(rp);
1264	/* And finally remove it. */
1265	raw3270_delete_device(rp);
1266}
1267
1268/*
1269 * Set 3270 device offline.
1270 */
1271static int raw3270_set_offline(struct ccw_device *cdev)
1272{
1273	struct raw3270 *rp;
1274
1275	rp = dev_get_drvdata(&cdev->dev);
1276	if (test_bit(RAW3270_FLAGS_CONSOLE, &rp->flags))
1277		return -EBUSY;
1278	raw3270_remove(cdev);
1279	return 0;
1280}
1281
1282static struct ccw_device_id raw3270_id[] = {
1283	{ CCW_DEVICE(0x3270, 0) },
1284	{ CCW_DEVICE(0x3271, 0) },
1285	{ CCW_DEVICE(0x3272, 0) },
1286	{ CCW_DEVICE(0x3273, 0) },
1287	{ CCW_DEVICE(0x3274, 0) },
1288	{ CCW_DEVICE(0x3275, 0) },
1289	{ CCW_DEVICE(0x3276, 0) },
1290	{ CCW_DEVICE(0x3277, 0) },
1291	{ CCW_DEVICE(0x3278, 0) },
1292	{ CCW_DEVICE(0x3279, 0) },
1293	{ CCW_DEVICE(0x3174, 0) },
1294	{ /* end of list */ },
1295};
1296
1297static struct ccw_driver raw3270_ccw_driver = {
1298	.driver = {
1299		.name	= "3270",
1300		.owner	= THIS_MODULE,
1301	},
1302	.ids		= raw3270_id,
1303	.probe		= &raw3270_probe,
1304	.remove		= &raw3270_remove,
1305	.set_online	= &raw3270_set_online,
1306	.set_offline	= &raw3270_set_offline,
1307	.int_class	= IRQIO_C70,
1308};
1309
1310static int raw3270_init(void)
1311{
1312	struct raw3270 *rp;
1313	int rc;
1314
1315	if (raw3270_registered)
1316		return 0;
1317	raw3270_registered = 1;
1318	rc = ccw_driver_register(&raw3270_ccw_driver);
1319	if (rc == 0) {
1320		/* Create attributes for early (= console) device. */
1321		mutex_lock(&raw3270_mutex);
1322		class3270 = class_create("3270");
1323		list_for_each_entry(rp, &raw3270_devices, list) {
1324			get_device(&rp->cdev->dev);
1325			raw3270_create_attributes(rp);
1326		}
1327		mutex_unlock(&raw3270_mutex);
1328	}
1329	return rc;
1330}
1331
1332static void raw3270_exit(void)
1333{
1334	ccw_driver_unregister(&raw3270_ccw_driver);
1335	class_destroy(class3270);
1336}
1337
1338MODULE_LICENSE("GPL");
1339
1340module_init(raw3270_init);
1341module_exit(raw3270_exit);
1342