xref: /linux/drivers/s390/char/tape.h (revision 6f7e6393d1ce636bb7ec77a7fe7b77458fddf701)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *    tape device driver for 3490E tapes.
4  *
5  *  S390 and zSeries version
6  *    Copyright IBM Corp. 2001, 2009
7  *    Author(s): Carsten Otte <cotte@de.ibm.com>
8  *		 Tuan Ngo-Anh <ngoanh@de.ibm.com>
9  *		 Martin Schwidefsky <schwidefsky@de.ibm.com>
10  *		 Stefan Bader <shbader@de.ibm.com>
11  */
12 
13 #ifndef _TAPE_H
14 #define _TAPE_H
15 
16 #include <asm/ccwdev.h>
17 #include <asm/debug.h>
18 #include <asm/idals.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/mtio.h>
22 #include <linux/interrupt.h>
23 #include <linux/workqueue.h>
24 
25 struct gendisk;
26 
27 /*
28  * Define DBF_LIKE_HELL for lots of messages in the debug feature.
29  */
30 #define DBF_LIKE_HELL
31 #ifdef  DBF_LIKE_HELL
32 #define DBF_LH(level, str, ...) \
33 do { \
34 	debug_sprintf_event(TAPE_DBF_AREA, level, str, ## __VA_ARGS__); \
35 } while (0)
36 #else
37 #define DBF_LH(level, str, ...) do {} while(0)
38 #endif
39 
40 /*
41  * macros s390 debug feature (dbf)
42  */
43 #define DBF_EVENT(d_level, d_str...) \
44 do { \
45 	debug_sprintf_event(TAPE_DBF_AREA, d_level, d_str); \
46 } while (0)
47 
48 #define DBF_EXCEPTION(d_level, d_str...) \
49 do { \
50 	debug_sprintf_exception(TAPE_DBF_AREA, d_level, d_str); \
51 } while (0)
52 
53 #define TAPE_VERSION_MAJOR 2
54 #define TAPE_VERSION_MINOR 0
55 #define TAPE_MAGIC "tape"
56 
57 #define TAPE_MINORS_PER_DEV 2	    /* two minors per device */
58 #define TAPEBLOCK_HSEC_SIZE	2048
59 #define TAPEBLOCK_HSEC_S2B	2
60 #define TAPEBLOCK_RETRIES	5
61 
62 enum tape_medium_state {
63 	MS_UNKNOWN,
64 	MS_LOADED,
65 	MS_UNLOADED,
66 	MS_SIZE
67 };
68 
69 enum tape_state {
70 	TS_UNUSED=0,
71 	TS_IN_USE,
72 	TS_BLKUSE,
73 	TS_INIT,
74 	TS_NOT_OPER,
75 	TS_SIZE
76 };
77 
78 enum tape_op {
79 	TO_BLOCK,	/* Block read */
80 	TO_BSB,		/* Backward space block */
81 	TO_BSF,		/* Backward space filemark */
82 	TO_DSE,		/* Data security erase */
83 	TO_FSB,		/* Forward space block */
84 	TO_FSF,		/* Forward space filemark */
85 	TO_LBL,		/* Locate block label */
86 	TO_NOP,		/* No operation */
87 	TO_RBA,		/* Read backward */
88 	TO_RBI,		/* Read block information */
89 	TO_RFO,		/* Read forward */
90 	TO_REW,		/* Rewind tape */
91 	TO_RUN,		/* Rewind and unload tape */
92 	TO_WRI,		/* Write block */
93 	TO_WTM,		/* Write tape mark */
94 	TO_MSEN,	/* Medium sense */
95 	TO_LOAD,	/* Load tape */
96 	TO_READ_CONFIG, /* Read configuration data */
97 	TO_READ_ATTMSG, /* Read attention message */
98 	TO_DIS,		/* Tape display */
99 	TO_ASSIGN,	/* Assign tape to channel path */
100 	TO_UNASSIGN,	/* Unassign tape from channel path */
101 	TO_RDC,		/* Read device characteristics */
102 	TO_SIZE,	/* #entries in tape_op_t */
103 };
104 
105 /* Forward declaration */
106 struct tape_device;
107 
108 /* tape_request->status can be: */
109 enum tape_request_status {
110 	TAPE_REQUEST_INIT,	/* request is ready to be processed */
111 	TAPE_REQUEST_QUEUED,	/* request is queued to be processed */
112 	TAPE_REQUEST_IN_IO,	/* request is currently in IO */
113 	TAPE_REQUEST_DONE,	/* request is completed. */
114 	TAPE_REQUEST_CANCEL,	/* request should be canceled. */
115 	TAPE_REQUEST_LONG_BUSY, /* request has to be restarted after long busy */
116 };
117 
118 /* Tape CCW request */
119 struct tape_request {
120 	struct list_head list;		/* list head for request queueing. */
121 	struct tape_device *device;	/* tape device of this request */
122 	struct ccw1 *cpaddr;		/* address of the channel program. */
123 	void *cpdata;			/* pointer to ccw data. */
124 	enum tape_request_status status;/* status of this request */
125 	int options;			/* options for execution. */
126 	int retries;			/* retry counter for error recovery. */
127 	int rescnt;			/* residual count from devstat. */
128 	struct timer_list timer;	/* timer for std_assign_timeout(). */
129 	struct irb irb;			/* device status */
130 
131 	/* Callback for delivering final status. */
132 	void (*callback)(struct tape_request *, void *);
133 	void *callback_data;
134 
135 	enum tape_op op;
136 	int rc;
137 };
138 
139 /* Function type for magnetic tape commands */
140 typedef int (*tape_mtop_fn)(struct tape_device *, int);
141 
142 /* Size of the array containing the mtops for a discipline */
143 #define TAPE_NR_MTOPS (MTMKPART+1)
144 
145 /* Tape Discipline */
146 struct tape_discipline {
147 	struct module *owner;
148 	int  (*setup_device)(struct tape_device *);
149 	void (*cleanup_device)(struct tape_device *);
150 	int (*irq)(struct tape_device *, struct tape_request *, struct irb *);
151 	struct tape_request *(*read_block)(struct tape_device *);
152 	struct tape_request *(*write_block)(struct tape_device *);
153 	void (*process_eov)(struct tape_device*);
154 	/* Array of tape commands with TAPE_NR_MTOPS entries */
155 	tape_mtop_fn *mtop_array;
156 };
157 
158 /*
159  * The discipline irq function either returns an error code (<0) which
160  * means that the request has failed with an error or one of the following:
161  */
162 #define TAPE_IO_SUCCESS		0	/* request successful */
163 #define TAPE_IO_PENDING		1	/* request still running */
164 #define TAPE_IO_RETRY		2	/* retry to current request */
165 #define TAPE_IO_STOP		3	/* stop the running request */
166 #define TAPE_IO_LONG_BUSY	4	/* delay the running request */
167 
168 /* Char Frontend Data */
169 struct tape_char_data {
170 	struct idal_buffer **ibs;	/* idal buffer array for user char data */
171 	int block_size;			/*   of size block_size. */
172 };
173 
174 /* Tape Info */
175 struct tape_device {
176 	/* entry in tape_device_list */
177 	struct list_head		node;
178 
179 	int				cdev_id;
180 	struct ccw_device *		cdev;
181 	struct tape_class_device *	nt;
182 	struct tape_class_device *	rt;
183 
184 	/* Device mutex to serialize tape commands. */
185 	struct mutex			mutex;
186 
187 	/* Device discipline information. */
188 	struct tape_discipline *	discipline;
189 
190 	/* Generic status flags */
191 	long				tape_generic_status;
192 
193 	/* Device state information. */
194 	wait_queue_head_t		state_change_wq;
195 	enum tape_state			tape_state;
196 	enum tape_medium_state		medium_state;
197 	unsigned char *			modeset_byte;
198 
199 	/* Reference count. */
200 	atomic_t			ref_count;
201 
202 	/* Request queue. */
203 	struct list_head		req_queue;
204 
205 	/* Request wait queue. */
206 	wait_queue_head_t		wait_queue;
207 
208 	/* Each tape device has (currently) two minor numbers. */
209 	int				first_minor;
210 
211 	/* Number of tapemarks required for correct termination. */
212 	int				required_tapemarks;
213 
214 	/* Block ID of the BOF */
215 	unsigned int			bof;
216 
217 	/* Character device frontend data */
218 	struct tape_char_data		char_data;
219 
220 	/* Function to start or stop the next request later. */
221 	struct delayed_work		tape_dnr;
222 
223 	/* Timer for long busy */
224 	struct timer_list		lb_timeout;
225 
226 };
227 
228 /* Externals from tape_core.c */
229 extern struct tape_request *tape_alloc_request(int cplength, int datasize);
230 extern void tape_free_request(struct tape_request *);
231 extern int tape_check_idalbuffer(struct tape_device *device, size_t size);
232 extern int tape_do_io(struct tape_device *, struct tape_request *);
233 extern int tape_do_io_async(struct tape_device *, struct tape_request *);
234 extern int tape_do_io_interruptible(struct tape_device *, struct tape_request *);
235 extern int tape_cancel_io(struct tape_device *, struct tape_request *);
236 
237 static inline int
238 tape_do_io_free(struct tape_device *device, struct tape_request *request)
239 {
240 	int rc;
241 
242 	rc = tape_do_io(device, request);
243 	tape_free_request(request);
244 	return rc;
245 }
246 
247 static inline void
248 tape_do_io_async_free(struct tape_device *device, struct tape_request *request)
249 {
250 	request->callback = (void *) tape_free_request;
251 	request->callback_data = NULL;
252 	tape_do_io_async(device, request);
253 }
254 
255 extern int tape_open(struct tape_device *);
256 extern int tape_release(struct tape_device *);
257 extern int tape_mtop(struct tape_device *, int, int);
258 extern void tape_state_set(struct tape_device *, enum tape_state);
259 
260 extern int tape_generic_online(struct tape_device *, struct tape_discipline *);
261 extern int tape_generic_offline(struct ccw_device *);
262 
263 /* Externals from tape_devmap.c */
264 extern int tape_generic_probe(struct ccw_device *);
265 extern void tape_generic_remove(struct ccw_device *);
266 
267 extern struct tape_device *tape_find_device(int devindex);
268 extern struct tape_device *tape_get_device(struct tape_device *);
269 extern void tape_put_device(struct tape_device *);
270 
271 /* Externals from tape_char.c */
272 extern int tapechar_init(void);
273 extern void tapechar_exit(void);
274 extern int  tapechar_setup_device(struct tape_device *);
275 extern void tapechar_cleanup_device(struct tape_device *);
276 
277 /* Externals from tape_3490.c */
278 extern int tape_3490_init(void);
279 extern void tape_3490_exit(void);
280 
281 /* tape initialisation functions */
282 #ifdef CONFIG_PROC_FS
283 extern void tape_proc_init (void);
284 extern void tape_proc_cleanup (void);
285 #else
286 static inline void tape_proc_init (void) {;}
287 static inline void tape_proc_cleanup (void) {;}
288 #endif
289 
290 /* a function for dumping device sense info */
291 extern void tape_dump_sense_dbf(struct tape_device *, struct tape_request *,
292 				struct irb *);
293 
294 /* functions for handling the status of a device */
295 extern void tape_med_state_set(struct tape_device *, enum tape_medium_state);
296 
297 /* The debug area */
298 extern debug_info_t *TAPE_DBF_AREA;
299 
300 /* functions for building ccws */
301 static inline struct ccw1 *
302 tape_ccw_cc(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
303 {
304 	ccw->cmd_code = cmd_code;
305 	ccw->flags = CCW_FLAG_CC;
306 	ccw->count = memsize;
307 	ccw->cda = 0;
308 	if (cda)
309 		ccw->cda = virt_to_dma32(cda);
310 	return ccw + 1;
311 }
312 
313 static inline struct ccw1 *
314 tape_ccw_end(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
315 {
316 	ccw->cmd_code = cmd_code;
317 	ccw->flags = 0;
318 	ccw->count = memsize;
319 	ccw->cda = 0;
320 	if (cda)
321 		ccw->cda = virt_to_dma32(cda);
322 	return ccw + 1;
323 }
324 
325 static inline struct ccw1 *
326 tape_ccw_cmd(struct ccw1 *ccw, __u8 cmd_code)
327 {
328 	ccw->cmd_code = cmd_code;
329 	ccw->flags = 0;
330 	ccw->count = 0;
331 	ccw->cda = virt_to_dma32(&ccw->cmd_code);
332 	return ccw + 1;
333 }
334 
335 static inline struct ccw1 *
336 tape_ccw_repeat(struct ccw1 *ccw, __u8 cmd_code, int count)
337 {
338 	while (count-- > 0) {
339 		ccw->cmd_code = cmd_code;
340 		ccw->flags = CCW_FLAG_CC;
341 		ccw->count = 0;
342 		ccw->cda = virt_to_dma32(&ccw->cmd_code);
343 		ccw++;
344 	}
345 	return ccw;
346 }
347 
348 static inline struct ccw1 *
349 tape_ccw_dc_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
350 {
351 	ccw->cmd_code = cmd_code;
352 	ccw->flags    = CCW_FLAG_DC;
353 	idal_buffer_set_cda(idal, ccw);
354 	return ccw + 1;
355 }
356 
357 static inline struct ccw1 *
358 tape_ccw_cc_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
359 {
360 	ccw->cmd_code = cmd_code;
361 	ccw->flags    = CCW_FLAG_CC;
362 	idal_buffer_set_cda(idal, ccw);
363 	return ccw + 1;
364 }
365 
366 static inline struct ccw1 *
367 tape_ccw_end_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
368 {
369 	ccw->cmd_code = cmd_code;
370 	ccw->flags    = 0;
371 	idal_buffer_set_cda(idal, ccw);
372 	return ccw + 1;
373 }
374 
375 /* Global vars */
376 extern const char *tape_state_verbose[];
377 extern const char *tape_op_verbose[];
378 
379 #endif /* for ifdef tape.h */
380