xref: /linux/drivers/s390/char/tape.h (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
1 /*
2  *  drivers/s390/char/tape.h
3  *    tape device driver for 3480/3490E/3590 tapes.
4  *
5  *  S390 and zSeries version
6  *    Copyright (C) 2001,2005 IBM Deutschland Entwicklung GmbH, IBM Corporation
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_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 };
116 
117 /* Tape CCW request */
118 struct tape_request {
119 	struct list_head list;		/* list head for request queueing. */
120 	struct tape_device *device;	/* tape device of this request */
121 	struct ccw1 *cpaddr;		/* address of the channel program. */
122 	void *cpdata;			/* pointer to ccw data. */
123 	enum tape_request_status status;/* status of this request */
124 	int options;			/* options for execution. */
125 	int retries;			/* retry counter for error recovery. */
126 	int rescnt;			/* residual count from devstat. */
127 
128 	/* Callback for delivering final status. */
129 	void (*callback)(struct tape_request *, void *);
130 	void *callback_data;
131 
132 	enum tape_op op;
133 	int rc;
134 };
135 
136 /* Function type for magnetic tape commands */
137 typedef int (*tape_mtop_fn)(struct tape_device *, int);
138 
139 /* Size of the array containing the mtops for a discipline */
140 #define TAPE_NR_MTOPS (MTMKPART+1)
141 
142 /* Tape Discipline */
143 struct tape_discipline {
144 	struct module *owner;
145 	int  (*setup_device)(struct tape_device *);
146 	void (*cleanup_device)(struct tape_device *);
147 	int (*irq)(struct tape_device *, struct tape_request *, struct irb *);
148 	struct tape_request *(*read_block)(struct tape_device *, size_t);
149 	struct tape_request *(*write_block)(struct tape_device *, size_t);
150 	void (*process_eov)(struct tape_device*);
151 #ifdef CONFIG_S390_TAPE_BLOCK
152 	/* Block device stuff. */
153 	struct tape_request *(*bread)(struct tape_device *, struct request *);
154 	void (*check_locate)(struct tape_device *, struct tape_request *);
155 	void (*free_bread)(struct tape_request *);
156 #endif
157 	/* ioctl function for additional ioctls. */
158 	int (*ioctl_fn)(struct tape_device *, unsigned int, unsigned long);
159 	/* Array of tape commands with TAPE_NR_MTOPS entries */
160 	tape_mtop_fn *mtop_array;
161 };
162 
163 /*
164  * The discipline irq function either returns an error code (<0) which
165  * means that the request has failed with an error or one of the following:
166  */
167 #define TAPE_IO_SUCCESS 0	/* request successful */
168 #define TAPE_IO_PENDING 1	/* request still running */
169 #define TAPE_IO_RETRY	2	/* retry to current request */
170 #define TAPE_IO_STOP	3	/* stop the running request */
171 
172 /* Char Frontend Data */
173 struct tape_char_data {
174 	struct idal_buffer *idal_buf;	/* idal buffer for user char data */
175 	int block_size;			/*   of size block_size. */
176 };
177 
178 #ifdef CONFIG_S390_TAPE_BLOCK
179 /* Block Frontend Data */
180 struct tape_blk_data
181 {
182 	/* Block device request queue. */
183 	request_queue_t *	request_queue;
184 	spinlock_t		request_queue_lock;
185 
186 	/* Task to move entries from block request to CCS request queue. */
187 	struct work_struct	requeue_task;
188 	atomic_t		requeue_scheduled;
189 
190 	/* Current position on the tape. */
191 	long			block_position;
192 	int			medium_changed;
193 	struct gendisk *	disk;
194 };
195 #endif
196 
197 /* Tape Info */
198 struct tape_device {
199 	/* entry in tape_device_list */
200 	struct list_head		node;
201 
202 	int				cdev_id;
203 	struct ccw_device *		cdev;
204 	struct tape_class_device *	nt;
205 	struct tape_class_device *	rt;
206 
207 	/* Device discipline information. */
208 	struct tape_discipline *	discipline;
209 	void *				discdata;
210 
211 	/* Generic status flags */
212 	long				tape_generic_status;
213 
214 	/* Device state information. */
215 	wait_queue_head_t		state_change_wq;
216 	enum tape_state			tape_state;
217 	enum tape_medium_state		medium_state;
218 	unsigned char *			modeset_byte;
219 
220 	/* Reference count. */
221 	atomic_t			ref_count;
222 
223 	/* Request queue. */
224 	struct list_head		req_queue;
225 
226 	/* Each tape device has (currently) two minor numbers. */
227 	int				first_minor;
228 
229 	/* Number of tapemarks required for correct termination. */
230 	int				required_tapemarks;
231 
232 	/* Block ID of the BOF */
233 	unsigned int			bof;
234 
235 	/* Character device frontend data */
236 	struct tape_char_data		char_data;
237 #ifdef CONFIG_S390_TAPE_BLOCK
238 	/* Block dev frontend data */
239 	struct tape_blk_data		blk_data;
240 #endif
241 
242 	/* Function to start or stop the next request later. */
243 	struct work_struct		tape_dnr;
244 };
245 
246 /* Externals from tape_core.c */
247 extern struct tape_request *tape_alloc_request(int cplength, int datasize);
248 extern void tape_free_request(struct tape_request *);
249 extern int tape_do_io(struct tape_device *, struct tape_request *);
250 extern int tape_do_io_async(struct tape_device *, struct tape_request *);
251 extern int tape_do_io_interruptible(struct tape_device *, struct tape_request *);
252 extern int tape_cancel_io(struct tape_device *, struct tape_request *);
253 void tape_hotplug_event(struct tape_device *, int major, int action);
254 
255 static inline int
256 tape_do_io_free(struct tape_device *device, struct tape_request *request)
257 {
258 	int rc;
259 
260 	rc = tape_do_io(device, request);
261 	tape_free_request(request);
262 	return rc;
263 }
264 
265 extern int tape_oper_handler(int irq, int status);
266 extern void tape_noper_handler(int irq, int status);
267 extern int tape_open(struct tape_device *);
268 extern int tape_release(struct tape_device *);
269 extern int tape_mtop(struct tape_device *, int, int);
270 extern void tape_state_set(struct tape_device *, enum tape_state);
271 
272 extern int tape_generic_online(struct tape_device *, struct tape_discipline *);
273 extern int tape_generic_offline(struct tape_device *device);
274 
275 /* Externals from tape_devmap.c */
276 extern int tape_generic_probe(struct ccw_device *);
277 extern void tape_generic_remove(struct ccw_device *);
278 
279 extern struct tape_device *tape_get_device(int devindex);
280 extern struct tape_device *tape_get_device_reference(struct tape_device *);
281 extern struct tape_device *tape_put_device(struct tape_device *);
282 
283 /* Externals from tape_char.c */
284 extern int tapechar_init(void);
285 extern void tapechar_exit(void);
286 extern int  tapechar_setup_device(struct tape_device *);
287 extern void tapechar_cleanup_device(struct tape_device *);
288 
289 /* Externals from tape_block.c */
290 #ifdef CONFIG_S390_TAPE_BLOCK
291 extern int tapeblock_init (void);
292 extern void tapeblock_exit(void);
293 extern int tapeblock_setup_device(struct tape_device *);
294 extern void tapeblock_cleanup_device(struct tape_device *);
295 #else
296 static inline int tapeblock_init (void) {return 0;}
297 static inline void tapeblock_exit (void) {;}
298 static inline int tapeblock_setup_device(struct tape_device *t) {return 0;}
299 static inline void tapeblock_cleanup_device (struct tape_device *t) {;}
300 #endif
301 
302 /* tape initialisation functions */
303 #ifdef CONFIG_PROC_FS
304 extern void tape_proc_init (void);
305 extern void tape_proc_cleanup (void);
306 #else
307 static inline void tape_proc_init (void) {;}
308 static inline void tape_proc_cleanup (void) {;}
309 #endif
310 
311 /* a function for dumping device sense info */
312 extern void tape_dump_sense(struct tape_device *, struct tape_request *,
313 			    struct irb *);
314 extern void tape_dump_sense_dbf(struct tape_device *, struct tape_request *,
315 				struct irb *);
316 
317 /* functions for handling the status of a device */
318 extern void tape_med_state_set(struct tape_device *, enum tape_medium_state);
319 
320 /* The debug area */
321 extern debug_info_t *TAPE_DBF_AREA;
322 
323 /* functions for building ccws */
324 static inline struct ccw1 *
325 tape_ccw_cc(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
326 {
327 	ccw->cmd_code = cmd_code;
328 	ccw->flags = CCW_FLAG_CC;
329 	ccw->count = memsize;
330 	ccw->cda = (__u32)(addr_t) cda;
331 	return ccw + 1;
332 }
333 
334 static inline struct ccw1 *
335 tape_ccw_end(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
336 {
337 	ccw->cmd_code = cmd_code;
338 	ccw->flags = 0;
339 	ccw->count = memsize;
340 	ccw->cda = (__u32)(addr_t) cda;
341 	return ccw + 1;
342 }
343 
344 static inline struct ccw1 *
345 tape_ccw_cmd(struct ccw1 *ccw, __u8 cmd_code)
346 {
347 	ccw->cmd_code = cmd_code;
348 	ccw->flags = 0;
349 	ccw->count = 0;
350 	ccw->cda = (__u32)(addr_t) &ccw->cmd_code;
351 	return ccw + 1;
352 }
353 
354 static inline struct ccw1 *
355 tape_ccw_repeat(struct ccw1 *ccw, __u8 cmd_code, int count)
356 {
357 	while (count-- > 0) {
358 		ccw->cmd_code = cmd_code;
359 		ccw->flags = CCW_FLAG_CC;
360 		ccw->count = 0;
361 		ccw->cda = (__u32)(addr_t) &ccw->cmd_code;
362 		ccw++;
363 	}
364 	return ccw;
365 }
366 
367 static inline struct ccw1 *
368 tape_ccw_cc_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
369 {
370 	ccw->cmd_code = cmd_code;
371 	ccw->flags    = CCW_FLAG_CC;
372 	idal_buffer_set_cda(idal, ccw);
373 	return ccw++;
374 }
375 
376 static inline struct ccw1 *
377 tape_ccw_end_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
378 {
379 	ccw->cmd_code = cmd_code;
380 	ccw->flags    = 0;
381 	idal_buffer_set_cda(idal, ccw);
382 	return ccw++;
383 }
384 
385 /* Global vars */
386 extern const char *tape_state_verbose[];
387 extern const char *tape_op_verbose[];
388 
389 #endif /* for ifdef tape.h */
390