xref: /openbmc/linux/drivers/s390/char/tape.h (revision a09d2831)
1 /*
2  *  drivers/s390/char/tape.h
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/blkdev.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/mtio.h>
23 #include <linux/interrupt.h>
24 #include <linux/workqueue.h>
25 
26 struct gendisk;
27 
28 /*
29  * Define DBF_LIKE_HELL for lots of messages in the debug feature.
30  */
31 #define DBF_LIKE_HELL
32 #ifdef  DBF_LIKE_HELL
33 #define DBF_LH(level, str, ...) \
34 do { \
35 	debug_sprintf_event(TAPE_DBF_AREA, level, str, ## __VA_ARGS__); \
36 } while (0)
37 #else
38 #define DBF_LH(level, str, ...) do {} while(0)
39 #endif
40 
41 /*
42  * macros s390 debug feature (dbf)
43  */
44 #define DBF_EVENT(d_level, d_str...) \
45 do { \
46 	debug_sprintf_event(TAPE_DBF_AREA, d_level, d_str); \
47 } while (0)
48 
49 #define DBF_EXCEPTION(d_level, d_str...) \
50 do { \
51 	debug_sprintf_exception(TAPE_DBF_AREA, d_level, d_str); \
52 } while (0)
53 
54 #define TAPE_VERSION_MAJOR 2
55 #define TAPE_VERSION_MINOR 0
56 #define TAPE_MAGIC "tape"
57 
58 #define TAPE_MINORS_PER_DEV 2	    /* two minors per device */
59 #define TAPEBLOCK_HSEC_SIZE	2048
60 #define TAPEBLOCK_HSEC_S2B	2
61 #define TAPEBLOCK_RETRIES	5
62 
63 enum tape_medium_state {
64 	MS_UNKNOWN,
65 	MS_LOADED,
66 	MS_UNLOADED,
67 	MS_SIZE
68 };
69 
70 enum tape_state {
71 	TS_UNUSED=0,
72 	TS_IN_USE,
73 	TS_BLKUSE,
74 	TS_INIT,
75 	TS_NOT_OPER,
76 	TS_SIZE
77 };
78 
79 enum tape_op {
80 	TO_BLOCK,	/* Block read */
81 	TO_BSB,		/* Backward space block */
82 	TO_BSF,		/* Backward space filemark */
83 	TO_DSE,		/* Data security erase */
84 	TO_FSB,		/* Forward space block */
85 	TO_FSF,		/* Forward space filemark */
86 	TO_LBL,		/* Locate block label */
87 	TO_NOP,		/* No operation */
88 	TO_RBA,		/* Read backward */
89 	TO_RBI,		/* Read block information */
90 	TO_RFO,		/* Read forward */
91 	TO_REW,		/* Rewind tape */
92 	TO_RUN,		/* Rewind and unload tape */
93 	TO_WRI,		/* Write block */
94 	TO_WTM,		/* Write tape mark */
95 	TO_MSEN,	/* Medium sense */
96 	TO_LOAD,	/* Load tape */
97 	TO_READ_CONFIG, /* Read configuration data */
98 	TO_READ_ATTMSG, /* Read attention message */
99 	TO_DIS,		/* Tape display */
100 	TO_ASSIGN,	/* Assign tape to channel path */
101 	TO_UNASSIGN,	/* Unassign tape from channel path */
102 	TO_CRYPT_ON,	/* Enable encrpytion */
103 	TO_CRYPT_OFF,	/* Disable encrpytion */
104 	TO_KEKL_SET,	/* Set KEK label */
105 	TO_KEKL_QUERY,	/* Query KEK label */
106 	TO_RDC,		/* Read device characteristics */
107 	TO_SIZE,	/* #entries in tape_op_t */
108 };
109 
110 /* Forward declaration */
111 struct tape_device;
112 
113 /* tape_request->status can be: */
114 enum tape_request_status {
115 	TAPE_REQUEST_INIT,	/* request is ready to be processed */
116 	TAPE_REQUEST_QUEUED,	/* request is queued to be processed */
117 	TAPE_REQUEST_IN_IO,	/* request is currently in IO */
118 	TAPE_REQUEST_DONE,	/* request is completed. */
119 	TAPE_REQUEST_CANCEL,	/* request should be canceled. */
120 	TAPE_REQUEST_LONG_BUSY, /* request has to be restarted after long busy */
121 };
122 
123 /* Tape CCW request */
124 struct tape_request {
125 	struct list_head list;		/* list head for request queueing. */
126 	struct tape_device *device;	/* tape device of this request */
127 	struct ccw1 *cpaddr;		/* address of the channel program. */
128 	void *cpdata;			/* pointer to ccw data. */
129 	enum tape_request_status status;/* status of this request */
130 	int options;			/* options for execution. */
131 	int retries;			/* retry counter for error recovery. */
132 	int rescnt;			/* residual count from devstat. */
133 
134 	/* Callback for delivering final status. */
135 	void (*callback)(struct tape_request *, void *);
136 	void *callback_data;
137 
138 	enum tape_op op;
139 	int rc;
140 };
141 
142 /* Function type for magnetic tape commands */
143 typedef int (*tape_mtop_fn)(struct tape_device *, int);
144 
145 /* Size of the array containing the mtops for a discipline */
146 #define TAPE_NR_MTOPS (MTMKPART+1)
147 
148 /* Tape Discipline */
149 struct tape_discipline {
150 	struct module *owner;
151 	int  (*setup_device)(struct tape_device *);
152 	void (*cleanup_device)(struct tape_device *);
153 	int (*irq)(struct tape_device *, struct tape_request *, struct irb *);
154 	struct tape_request *(*read_block)(struct tape_device *, size_t);
155 	struct tape_request *(*write_block)(struct tape_device *, size_t);
156 	void (*process_eov)(struct tape_device*);
157 #ifdef CONFIG_S390_TAPE_BLOCK
158 	/* Block device stuff. */
159 	struct tape_request *(*bread)(struct tape_device *, struct request *);
160 	void (*check_locate)(struct tape_device *, struct tape_request *);
161 	void (*free_bread)(struct tape_request *);
162 #endif
163 	/* ioctl function for additional ioctls. */
164 	int (*ioctl_fn)(struct tape_device *, unsigned int, unsigned long);
165 	/* Array of tape commands with TAPE_NR_MTOPS entries */
166 	tape_mtop_fn *mtop_array;
167 };
168 
169 /*
170  * The discipline irq function either returns an error code (<0) which
171  * means that the request has failed with an error or one of the following:
172  */
173 #define TAPE_IO_SUCCESS		0	/* request successful */
174 #define TAPE_IO_PENDING		1	/* request still running */
175 #define TAPE_IO_RETRY		2	/* retry to current request */
176 #define TAPE_IO_STOP		3	/* stop the running request */
177 #define TAPE_IO_LONG_BUSY	4	/* delay the running request */
178 
179 /* Char Frontend Data */
180 struct tape_char_data {
181 	struct idal_buffer *idal_buf;	/* idal buffer for user char data */
182 	int block_size;			/*   of size block_size. */
183 };
184 
185 #ifdef CONFIG_S390_TAPE_BLOCK
186 /* Block Frontend Data */
187 struct tape_blk_data
188 {
189 	struct tape_device *	device;
190 	/* Block device request queue. */
191 	struct request_queue *	request_queue;
192 	spinlock_t		request_queue_lock;
193 
194 	/* Task to move entries from block request to CCS request queue. */
195 	struct work_struct	requeue_task;
196 	atomic_t		requeue_scheduled;
197 
198 	/* Current position on the tape. */
199 	long			block_position;
200 	int			medium_changed;
201 	struct gendisk *	disk;
202 };
203 #endif
204 
205 /* Tape Info */
206 struct tape_device {
207 	/* entry in tape_device_list */
208 	struct list_head		node;
209 
210 	int				cdev_id;
211 	struct ccw_device *		cdev;
212 	struct tape_class_device *	nt;
213 	struct tape_class_device *	rt;
214 
215 	/* Device mutex to serialize tape commands. */
216 	struct mutex			mutex;
217 
218 	/* Device discipline information. */
219 	struct tape_discipline *	discipline;
220 	void *				discdata;
221 
222 	/* Generic status flags */
223 	long				tape_generic_status;
224 
225 	/* Device state information. */
226 	wait_queue_head_t		state_change_wq;
227 	enum tape_state			tape_state;
228 	enum tape_medium_state		medium_state;
229 	unsigned char *			modeset_byte;
230 
231 	/* Reference count. */
232 	atomic_t			ref_count;
233 
234 	/* Request queue. */
235 	struct list_head		req_queue;
236 
237 	/* Request wait queue. */
238 	wait_queue_head_t		wait_queue;
239 
240 	/* Each tape device has (currently) two minor numbers. */
241 	int				first_minor;
242 
243 	/* Number of tapemarks required for correct termination. */
244 	int				required_tapemarks;
245 
246 	/* Block ID of the BOF */
247 	unsigned int			bof;
248 
249 	/* Character device frontend data */
250 	struct tape_char_data		char_data;
251 #ifdef CONFIG_S390_TAPE_BLOCK
252 	/* Block dev frontend data */
253 	struct tape_blk_data		blk_data;
254 #endif
255 
256 	/* Function to start or stop the next request later. */
257 	struct delayed_work		tape_dnr;
258 
259 	/* Timer for long busy */
260 	struct timer_list		lb_timeout;
261 
262 };
263 
264 /* Externals from tape_core.c */
265 extern struct tape_request *tape_alloc_request(int cplength, int datasize);
266 extern void tape_free_request(struct tape_request *);
267 extern int tape_do_io(struct tape_device *, struct tape_request *);
268 extern int tape_do_io_async(struct tape_device *, struct tape_request *);
269 extern int tape_do_io_interruptible(struct tape_device *, struct tape_request *);
270 extern int tape_cancel_io(struct tape_device *, struct tape_request *);
271 void tape_hotplug_event(struct tape_device *, int major, int action);
272 
273 static inline int
274 tape_do_io_free(struct tape_device *device, struct tape_request *request)
275 {
276 	int rc;
277 
278 	rc = tape_do_io(device, request);
279 	tape_free_request(request);
280 	return rc;
281 }
282 
283 extern int tape_oper_handler(int irq, int status);
284 extern void tape_noper_handler(int irq, int status);
285 extern int tape_open(struct tape_device *);
286 extern int tape_release(struct tape_device *);
287 extern int tape_mtop(struct tape_device *, int, int);
288 extern void tape_state_set(struct tape_device *, enum tape_state);
289 
290 extern int tape_generic_online(struct tape_device *, struct tape_discipline *);
291 extern int tape_generic_offline(struct ccw_device *);
292 extern int tape_generic_pm_suspend(struct ccw_device *);
293 
294 /* Externals from tape_devmap.c */
295 extern int tape_generic_probe(struct ccw_device *);
296 extern void tape_generic_remove(struct ccw_device *);
297 
298 extern struct tape_device *tape_find_device(int devindex);
299 extern struct tape_device *tape_get_device(struct tape_device *);
300 extern void tape_put_device(struct tape_device *);
301 
302 /* Externals from tape_char.c */
303 extern int tapechar_init(void);
304 extern void tapechar_exit(void);
305 extern int  tapechar_setup_device(struct tape_device *);
306 extern void tapechar_cleanup_device(struct tape_device *);
307 
308 /* Externals from tape_block.c */
309 #ifdef CONFIG_S390_TAPE_BLOCK
310 extern int tapeblock_init (void);
311 extern void tapeblock_exit(void);
312 extern int tapeblock_setup_device(struct tape_device *);
313 extern void tapeblock_cleanup_device(struct tape_device *);
314 #else
315 static inline int tapeblock_init (void) {return 0;}
316 static inline void tapeblock_exit (void) {;}
317 static inline int tapeblock_setup_device(struct tape_device *t) {return 0;}
318 static inline void tapeblock_cleanup_device (struct tape_device *t) {;}
319 #endif
320 
321 /* tape initialisation functions */
322 #ifdef CONFIG_PROC_FS
323 extern void tape_proc_init (void);
324 extern void tape_proc_cleanup (void);
325 #else
326 static inline void tape_proc_init (void) {;}
327 static inline void tape_proc_cleanup (void) {;}
328 #endif
329 
330 /* a function for dumping device sense info */
331 extern void tape_dump_sense_dbf(struct tape_device *, struct tape_request *,
332 				struct irb *);
333 
334 /* functions for handling the status of a device */
335 extern void tape_med_state_set(struct tape_device *, enum tape_medium_state);
336 
337 /* The debug area */
338 extern debug_info_t *TAPE_DBF_AREA;
339 
340 /* functions for building ccws */
341 static inline struct ccw1 *
342 tape_ccw_cc(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
343 {
344 	ccw->cmd_code = cmd_code;
345 	ccw->flags = CCW_FLAG_CC;
346 	ccw->count = memsize;
347 	ccw->cda = (__u32)(addr_t) cda;
348 	return ccw + 1;
349 }
350 
351 static inline struct ccw1 *
352 tape_ccw_end(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
353 {
354 	ccw->cmd_code = cmd_code;
355 	ccw->flags = 0;
356 	ccw->count = memsize;
357 	ccw->cda = (__u32)(addr_t) cda;
358 	return ccw + 1;
359 }
360 
361 static inline struct ccw1 *
362 tape_ccw_cmd(struct ccw1 *ccw, __u8 cmd_code)
363 {
364 	ccw->cmd_code = cmd_code;
365 	ccw->flags = 0;
366 	ccw->count = 0;
367 	ccw->cda = (__u32)(addr_t) &ccw->cmd_code;
368 	return ccw + 1;
369 }
370 
371 static inline struct ccw1 *
372 tape_ccw_repeat(struct ccw1 *ccw, __u8 cmd_code, int count)
373 {
374 	while (count-- > 0) {
375 		ccw->cmd_code = cmd_code;
376 		ccw->flags = CCW_FLAG_CC;
377 		ccw->count = 0;
378 		ccw->cda = (__u32)(addr_t) &ccw->cmd_code;
379 		ccw++;
380 	}
381 	return ccw;
382 }
383 
384 static inline struct ccw1 *
385 tape_ccw_cc_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
386 {
387 	ccw->cmd_code = cmd_code;
388 	ccw->flags    = CCW_FLAG_CC;
389 	idal_buffer_set_cda(idal, ccw);
390 	return ccw++;
391 }
392 
393 static inline struct ccw1 *
394 tape_ccw_end_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
395 {
396 	ccw->cmd_code = cmd_code;
397 	ccw->flags    = 0;
398 	idal_buffer_set_cda(idal, ccw);
399 	return ccw++;
400 }
401 
402 /* Global vars */
403 extern const char *tape_state_verbose[];
404 extern const char *tape_op_verbose[];
405 
406 #endif /* for ifdef tape.h */
407