xref: /linux/drivers/s390/char/tape.h (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *    tape device driver for 3480/3490E/3590 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_CRYPT_ON,	/* Enable encrpytion */
102 	TO_CRYPT_OFF,	/* Disable encrpytion */
103 	TO_KEKL_SET,	/* Set KEK label */
104 	TO_KEKL_QUERY,	/* Query KEK label */
105 	TO_RDC,		/* Read device characteristics */
106 	TO_SIZE,	/* #entries in tape_op_t */
107 };
108 
109 /* Forward declaration */
110 struct tape_device;
111 
112 /* tape_request->status can be: */
113 enum tape_request_status {
114 	TAPE_REQUEST_INIT,	/* request is ready to be processed */
115 	TAPE_REQUEST_QUEUED,	/* request is queued to be processed */
116 	TAPE_REQUEST_IN_IO,	/* request is currently in IO */
117 	TAPE_REQUEST_DONE,	/* request is completed. */
118 	TAPE_REQUEST_CANCEL,	/* request should be canceled. */
119 	TAPE_REQUEST_LONG_BUSY, /* request has to be restarted after long busy */
120 };
121 
122 /* Tape CCW request */
123 struct tape_request {
124 	struct list_head list;		/* list head for request queueing. */
125 	struct tape_device *device;	/* tape device of this request */
126 	struct ccw1 *cpaddr;		/* address of the channel program. */
127 	void *cpdata;			/* pointer to ccw data. */
128 	enum tape_request_status status;/* status of this request */
129 	int options;			/* options for execution. */
130 	int retries;			/* retry counter for error recovery. */
131 	int rescnt;			/* residual count from devstat. */
132 	struct timer_list timer;	/* timer for std_assign_timeout(). */
133 	struct irb irb;			/* device status */
134 
135 	/* Callback for delivering final status. */
136 	void (*callback)(struct tape_request *, void *);
137 	void *callback_data;
138 
139 	enum tape_op op;
140 	int rc;
141 };
142 
143 /* Function type for magnetic tape commands */
144 typedef int (*tape_mtop_fn)(struct tape_device *, int);
145 
146 /* Size of the array containing the mtops for a discipline */
147 #define TAPE_NR_MTOPS (MTMKPART+1)
148 
149 /* Tape Discipline */
150 struct tape_discipline {
151 	struct module *owner;
152 	int  (*setup_device)(struct tape_device *);
153 	void (*cleanup_device)(struct tape_device *);
154 	int (*irq)(struct tape_device *, struct tape_request *, struct irb *);
155 	struct tape_request *(*read_block)(struct tape_device *);
156 	struct tape_request *(*write_block)(struct tape_device *);
157 	void (*process_eov)(struct tape_device*);
158 	/* ioctl function for additional ioctls. */
159 	int (*ioctl_fn)(struct tape_device *, unsigned int, unsigned long);
160 	/* Array of tape commands with TAPE_NR_MTOPS entries */
161 	tape_mtop_fn *mtop_array;
162 };
163 
164 /*
165  * The discipline irq function either returns an error code (<0) which
166  * means that the request has failed with an error or one of the following:
167  */
168 #define TAPE_IO_SUCCESS		0	/* request successful */
169 #define TAPE_IO_PENDING		1	/* request still running */
170 #define TAPE_IO_RETRY		2	/* retry to current request */
171 #define TAPE_IO_STOP		3	/* stop the running request */
172 #define TAPE_IO_LONG_BUSY	4	/* delay the running request */
173 
174 /* Char Frontend Data */
175 struct tape_char_data {
176 	struct idal_buffer **ibs;	/* idal buffer array for user char data */
177 	int block_size;			/*   of size block_size. */
178 };
179 
180 /* Tape Info */
181 struct tape_device {
182 	/* entry in tape_device_list */
183 	struct list_head		node;
184 
185 	int				cdev_id;
186 	struct ccw_device *		cdev;
187 	struct tape_class_device *	nt;
188 	struct tape_class_device *	rt;
189 
190 	/* Device mutex to serialize tape commands. */
191 	struct mutex			mutex;
192 
193 	/* Device discipline information. */
194 	struct tape_discipline *	discipline;
195 	void *				discdata;
196 
197 	/* Generic status flags */
198 	long				tape_generic_status;
199 
200 	/* Device state information. */
201 	wait_queue_head_t		state_change_wq;
202 	enum tape_state			tape_state;
203 	enum tape_medium_state		medium_state;
204 	unsigned char *			modeset_byte;
205 
206 	/* Reference count. */
207 	atomic_t			ref_count;
208 
209 	/* Request queue. */
210 	struct list_head		req_queue;
211 
212 	/* Request wait queue. */
213 	wait_queue_head_t		wait_queue;
214 
215 	/* Each tape device has (currently) two minor numbers. */
216 	int				first_minor;
217 
218 	/* Number of tapemarks required for correct termination. */
219 	int				required_tapemarks;
220 
221 	/* Block ID of the BOF */
222 	unsigned int			bof;
223 
224 	/* Character device frontend data */
225 	struct tape_char_data		char_data;
226 
227 	/* Function to start or stop the next request later. */
228 	struct delayed_work		tape_dnr;
229 
230 	/* Timer for long busy */
231 	struct timer_list		lb_timeout;
232 
233 };
234 
235 /* Externals from tape_core.c */
236 extern struct tape_request *tape_alloc_request(int cplength, int datasize);
237 extern void tape_free_request(struct tape_request *);
238 extern int tape_check_idalbuffer(struct tape_device *device, size_t size);
239 extern int tape_do_io(struct tape_device *, struct tape_request *);
240 extern int tape_do_io_async(struct tape_device *, struct tape_request *);
241 extern int tape_do_io_interruptible(struct tape_device *, struct tape_request *);
242 extern int tape_cancel_io(struct tape_device *, struct tape_request *);
243 
244 static inline int
245 tape_do_io_free(struct tape_device *device, struct tape_request *request)
246 {
247 	int rc;
248 
249 	rc = tape_do_io(device, request);
250 	tape_free_request(request);
251 	return rc;
252 }
253 
254 static inline void
255 tape_do_io_async_free(struct tape_device *device, struct tape_request *request)
256 {
257 	request->callback = (void *) tape_free_request;
258 	request->callback_data = NULL;
259 	tape_do_io_async(device, request);
260 }
261 
262 extern int tape_open(struct tape_device *);
263 extern int tape_release(struct tape_device *);
264 extern int tape_mtop(struct tape_device *, int, int);
265 extern void tape_state_set(struct tape_device *, enum tape_state);
266 
267 extern int tape_generic_online(struct tape_device *, struct tape_discipline *);
268 extern int tape_generic_offline(struct ccw_device *);
269 
270 /* Externals from tape_devmap.c */
271 extern int tape_generic_probe(struct ccw_device *);
272 extern void tape_generic_remove(struct ccw_device *);
273 
274 extern struct tape_device *tape_find_device(int devindex);
275 extern struct tape_device *tape_get_device(struct tape_device *);
276 extern void tape_put_device(struct tape_device *);
277 
278 /* Externals from tape_char.c */
279 extern int tapechar_init(void);
280 extern void tapechar_exit(void);
281 extern int  tapechar_setup_device(struct tape_device *);
282 extern void tapechar_cleanup_device(struct tape_device *);
283 
284 /* tape initialisation functions */
285 #ifdef CONFIG_PROC_FS
286 extern void tape_proc_init (void);
287 extern void tape_proc_cleanup (void);
288 #else
289 static inline void tape_proc_init (void) {;}
290 static inline void tape_proc_cleanup (void) {;}
291 #endif
292 
293 /* a function for dumping device sense info */
294 extern void tape_dump_sense_dbf(struct tape_device *, struct tape_request *,
295 				struct irb *);
296 
297 /* functions for handling the status of a device */
298 extern void tape_med_state_set(struct tape_device *, enum tape_medium_state);
299 
300 /* The debug area */
301 extern debug_info_t *TAPE_DBF_AREA;
302 
303 /* functions for building ccws */
304 static inline struct ccw1 *
305 tape_ccw_cc(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
306 {
307 	ccw->cmd_code = cmd_code;
308 	ccw->flags = CCW_FLAG_CC;
309 	ccw->count = memsize;
310 	ccw->cda = 0;
311 	if (cda)
312 		ccw->cda = virt_to_dma32(cda);
313 	return ccw + 1;
314 }
315 
316 static inline struct ccw1 *
317 tape_ccw_end(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
318 {
319 	ccw->cmd_code = cmd_code;
320 	ccw->flags = 0;
321 	ccw->count = memsize;
322 	ccw->cda = 0;
323 	if (cda)
324 		ccw->cda = virt_to_dma32(cda);
325 	return ccw + 1;
326 }
327 
328 static inline struct ccw1 *
329 tape_ccw_cmd(struct ccw1 *ccw, __u8 cmd_code)
330 {
331 	ccw->cmd_code = cmd_code;
332 	ccw->flags = 0;
333 	ccw->count = 0;
334 	ccw->cda = virt_to_dma32(&ccw->cmd_code);
335 	return ccw + 1;
336 }
337 
338 static inline struct ccw1 *
339 tape_ccw_repeat(struct ccw1 *ccw, __u8 cmd_code, int count)
340 {
341 	while (count-- > 0) {
342 		ccw->cmd_code = cmd_code;
343 		ccw->flags = CCW_FLAG_CC;
344 		ccw->count = 0;
345 		ccw->cda = virt_to_dma32(&ccw->cmd_code);
346 		ccw++;
347 	}
348 	return ccw;
349 }
350 
351 static inline struct ccw1 *
352 tape_ccw_dc_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
353 {
354 	ccw->cmd_code = cmd_code;
355 	ccw->flags    = CCW_FLAG_DC;
356 	idal_buffer_set_cda(idal, ccw);
357 	return ccw + 1;
358 }
359 
360 static inline struct ccw1 *
361 tape_ccw_cc_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
362 {
363 	ccw->cmd_code = cmd_code;
364 	ccw->flags    = CCW_FLAG_CC;
365 	idal_buffer_set_cda(idal, ccw);
366 	return ccw + 1;
367 }
368 
369 static inline struct ccw1 *
370 tape_ccw_end_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
371 {
372 	ccw->cmd_code = cmd_code;
373 	ccw->flags    = 0;
374 	idal_buffer_set_cda(idal, ccw);
375 	return ccw + 1;
376 }
377 
378 /* Global vars */
379 extern const char *tape_state_verbose[];
380 extern const char *tape_op_verbose[];
381 
382 #endif /* for ifdef tape.h */
383