xref: /openbmc/linux/drivers/s390/char/tape.h (revision 8730046c)
1 /*
2  *    tape device driver for 3480/3490E/3590 tapes.
3  *
4  *  S390 and zSeries version
5  *    Copyright IBM Corp. 2001, 2009
6  *    Author(s): Carsten Otte <cotte@de.ibm.com>
7  *		 Tuan Ngo-Anh <ngoanh@de.ibm.com>
8  *		 Martin Schwidefsky <schwidefsky@de.ibm.com>
9  *		 Stefan Bader <shbader@de.ibm.com>
10  */
11 
12 #ifndef _TAPE_H
13 #define _TAPE_H
14 
15 #include <asm/ccwdev.h>
16 #include <asm/debug.h>
17 #include <asm/idals.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/mtio.h>
21 #include <linux/interrupt.h>
22 #include <linux/workqueue.h>
23 
24 struct gendisk;
25 
26 /*
27  * Define DBF_LIKE_HELL for lots of messages in the debug feature.
28  */
29 #define DBF_LIKE_HELL
30 #ifdef  DBF_LIKE_HELL
31 #define DBF_LH(level, str, ...) \
32 do { \
33 	debug_sprintf_event(TAPE_DBF_AREA, level, str, ## __VA_ARGS__); \
34 } while (0)
35 #else
36 #define DBF_LH(level, str, ...) do {} while(0)
37 #endif
38 
39 /*
40  * macros s390 debug feature (dbf)
41  */
42 #define DBF_EVENT(d_level, d_str...) \
43 do { \
44 	debug_sprintf_event(TAPE_DBF_AREA, d_level, d_str); \
45 } while (0)
46 
47 #define DBF_EXCEPTION(d_level, d_str...) \
48 do { \
49 	debug_sprintf_exception(TAPE_DBF_AREA, d_level, d_str); \
50 } while (0)
51 
52 #define TAPE_VERSION_MAJOR 2
53 #define TAPE_VERSION_MINOR 0
54 #define TAPE_MAGIC "tape"
55 
56 #define TAPE_MINORS_PER_DEV 2	    /* two minors per device */
57 #define TAPEBLOCK_HSEC_SIZE	2048
58 #define TAPEBLOCK_HSEC_S2B	2
59 #define TAPEBLOCK_RETRIES	5
60 
61 enum tape_medium_state {
62 	MS_UNKNOWN,
63 	MS_LOADED,
64 	MS_UNLOADED,
65 	MS_SIZE
66 };
67 
68 enum tape_state {
69 	TS_UNUSED=0,
70 	TS_IN_USE,
71 	TS_BLKUSE,
72 	TS_INIT,
73 	TS_NOT_OPER,
74 	TS_SIZE
75 };
76 
77 enum tape_op {
78 	TO_BLOCK,	/* Block read */
79 	TO_BSB,		/* Backward space block */
80 	TO_BSF,		/* Backward space filemark */
81 	TO_DSE,		/* Data security erase */
82 	TO_FSB,		/* Forward space block */
83 	TO_FSF,		/* Forward space filemark */
84 	TO_LBL,		/* Locate block label */
85 	TO_NOP,		/* No operation */
86 	TO_RBA,		/* Read backward */
87 	TO_RBI,		/* Read block information */
88 	TO_RFO,		/* Read forward */
89 	TO_REW,		/* Rewind tape */
90 	TO_RUN,		/* Rewind and unload tape */
91 	TO_WRI,		/* Write block */
92 	TO_WTM,		/* Write tape mark */
93 	TO_MSEN,	/* Medium sense */
94 	TO_LOAD,	/* Load tape */
95 	TO_READ_CONFIG, /* Read configuration data */
96 	TO_READ_ATTMSG, /* Read attention message */
97 	TO_DIS,		/* Tape display */
98 	TO_ASSIGN,	/* Assign tape to channel path */
99 	TO_UNASSIGN,	/* Unassign tape from channel path */
100 	TO_CRYPT_ON,	/* Enable encrpytion */
101 	TO_CRYPT_OFF,	/* Disable encrpytion */
102 	TO_KEKL_SET,	/* Set KEK label */
103 	TO_KEKL_QUERY,	/* Query KEK label */
104 	TO_RDC,		/* Read device characteristics */
105 	TO_SIZE,	/* #entries in tape_op_t */
106 };
107 
108 /* Forward declaration */
109 struct tape_device;
110 
111 /* tape_request->status can be: */
112 enum tape_request_status {
113 	TAPE_REQUEST_INIT,	/* request is ready to be processed */
114 	TAPE_REQUEST_QUEUED,	/* request is queued to be processed */
115 	TAPE_REQUEST_IN_IO,	/* request is currently in IO */
116 	TAPE_REQUEST_DONE,	/* request is completed. */
117 	TAPE_REQUEST_CANCEL,	/* request should be canceled. */
118 	TAPE_REQUEST_LONG_BUSY, /* request has to be restarted after long busy */
119 };
120 
121 /* Tape CCW request */
122 struct tape_request {
123 	struct list_head list;		/* list head for request queueing. */
124 	struct tape_device *device;	/* tape device of this request */
125 	struct ccw1 *cpaddr;		/* address of the channel program. */
126 	void *cpdata;			/* pointer to ccw data. */
127 	enum tape_request_status status;/* status of this request */
128 	int options;			/* options for execution. */
129 	int retries;			/* retry counter for error recovery. */
130 	int rescnt;			/* residual count from devstat. */
131 
132 	/* Callback for delivering final status. */
133 	void (*callback)(struct tape_request *, void *);
134 	void *callback_data;
135 
136 	enum tape_op op;
137 	int rc;
138 };
139 
140 /* Function type for magnetic tape commands */
141 typedef int (*tape_mtop_fn)(struct tape_device *, int);
142 
143 /* Size of the array containing the mtops for a discipline */
144 #define TAPE_NR_MTOPS (MTMKPART+1)
145 
146 /* Tape Discipline */
147 struct tape_discipline {
148 	struct module *owner;
149 	int  (*setup_device)(struct tape_device *);
150 	void (*cleanup_device)(struct tape_device *);
151 	int (*irq)(struct tape_device *, struct tape_request *, struct irb *);
152 	struct tape_request *(*read_block)(struct tape_device *, size_t);
153 	struct tape_request *(*write_block)(struct tape_device *, size_t);
154 	void (*process_eov)(struct tape_device*);
155 	/* ioctl function for additional ioctls. */
156 	int (*ioctl_fn)(struct tape_device *, unsigned int, unsigned long);
157 	/* Array of tape commands with TAPE_NR_MTOPS entries */
158 	tape_mtop_fn *mtop_array;
159 };
160 
161 /*
162  * The discipline irq function either returns an error code (<0) which
163  * means that the request has failed with an error or one of the following:
164  */
165 #define TAPE_IO_SUCCESS		0	/* request successful */
166 #define TAPE_IO_PENDING		1	/* request still running */
167 #define TAPE_IO_RETRY		2	/* retry to current request */
168 #define TAPE_IO_STOP		3	/* stop the running request */
169 #define TAPE_IO_LONG_BUSY	4	/* delay the running request */
170 
171 /* Char Frontend Data */
172 struct tape_char_data {
173 	struct idal_buffer *idal_buf;	/* idal buffer for user char data */
174 	int block_size;			/*   of size block_size. */
175 };
176 
177 /* Tape Info */
178 struct tape_device {
179 	/* entry in tape_device_list */
180 	struct list_head		node;
181 
182 	int				cdev_id;
183 	struct ccw_device *		cdev;
184 	struct tape_class_device *	nt;
185 	struct tape_class_device *	rt;
186 
187 	/* Device mutex to serialize tape commands. */
188 	struct mutex			mutex;
189 
190 	/* Device discipline information. */
191 	struct tape_discipline *	discipline;
192 	void *				discdata;
193 
194 	/* Generic status flags */
195 	long				tape_generic_status;
196 
197 	/* Device state information. */
198 	wait_queue_head_t		state_change_wq;
199 	enum tape_state			tape_state;
200 	enum tape_medium_state		medium_state;
201 	unsigned char *			modeset_byte;
202 
203 	/* Reference count. */
204 	atomic_t			ref_count;
205 
206 	/* Request queue. */
207 	struct list_head		req_queue;
208 
209 	/* Request wait queue. */
210 	wait_queue_head_t		wait_queue;
211 
212 	/* Each tape device has (currently) two minor numbers. */
213 	int				first_minor;
214 
215 	/* Number of tapemarks required for correct termination. */
216 	int				required_tapemarks;
217 
218 	/* Block ID of the BOF */
219 	unsigned int			bof;
220 
221 	/* Character device frontend data */
222 	struct tape_char_data		char_data;
223 
224 	/* Function to start or stop the next request later. */
225 	struct delayed_work		tape_dnr;
226 
227 	/* Timer for long busy */
228 	struct timer_list		lb_timeout;
229 
230 };
231 
232 /* Externals from tape_core.c */
233 extern struct tape_request *tape_alloc_request(int cplength, int datasize);
234 extern void tape_free_request(struct tape_request *);
235 extern int tape_do_io(struct tape_device *, struct tape_request *);
236 extern int tape_do_io_async(struct tape_device *, struct tape_request *);
237 extern int tape_do_io_interruptible(struct tape_device *, struct tape_request *);
238 extern int tape_cancel_io(struct tape_device *, struct tape_request *);
239 void tape_hotplug_event(struct tape_device *, int major, int action);
240 
241 static inline int
242 tape_do_io_free(struct tape_device *device, struct tape_request *request)
243 {
244 	int rc;
245 
246 	rc = tape_do_io(device, request);
247 	tape_free_request(request);
248 	return rc;
249 }
250 
251 static inline void
252 tape_do_io_async_free(struct tape_device *device, struct tape_request *request)
253 {
254 	request->callback = (void *) tape_free_request;
255 	request->callback_data = NULL;
256 	tape_do_io_async(device, request);
257 }
258 
259 extern int tape_oper_handler(int irq, int status);
260 extern void tape_noper_handler(int irq, int status);
261 extern int tape_open(struct tape_device *);
262 extern int tape_release(struct tape_device *);
263 extern int tape_mtop(struct tape_device *, int, int);
264 extern void tape_state_set(struct tape_device *, enum tape_state);
265 
266 extern int tape_generic_online(struct tape_device *, struct tape_discipline *);
267 extern int tape_generic_offline(struct ccw_device *);
268 extern int tape_generic_pm_suspend(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 = (__u32)(addr_t) cda;
311 	return ccw + 1;
312 }
313 
314 static inline struct ccw1 *
315 tape_ccw_end(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
316 {
317 	ccw->cmd_code = cmd_code;
318 	ccw->flags = 0;
319 	ccw->count = memsize;
320 	ccw->cda = (__u32)(addr_t) cda;
321 	return ccw + 1;
322 }
323 
324 static inline struct ccw1 *
325 tape_ccw_cmd(struct ccw1 *ccw, __u8 cmd_code)
326 {
327 	ccw->cmd_code = cmd_code;
328 	ccw->flags = 0;
329 	ccw->count = 0;
330 	ccw->cda = (__u32)(addr_t) &ccw->cmd_code;
331 	return ccw + 1;
332 }
333 
334 static inline struct ccw1 *
335 tape_ccw_repeat(struct ccw1 *ccw, __u8 cmd_code, int count)
336 {
337 	while (count-- > 0) {
338 		ccw->cmd_code = cmd_code;
339 		ccw->flags = CCW_FLAG_CC;
340 		ccw->count = 0;
341 		ccw->cda = (__u32)(addr_t) &ccw->cmd_code;
342 		ccw++;
343 	}
344 	return ccw;
345 }
346 
347 static inline struct ccw1 *
348 tape_ccw_cc_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
349 {
350 	ccw->cmd_code = cmd_code;
351 	ccw->flags    = CCW_FLAG_CC;
352 	idal_buffer_set_cda(idal, ccw);
353 	return ccw++;
354 }
355 
356 static inline struct ccw1 *
357 tape_ccw_end_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
358 {
359 	ccw->cmd_code = cmd_code;
360 	ccw->flags    = 0;
361 	idal_buffer_set_cda(idal, ccw);
362 	return ccw++;
363 }
364 
365 /* Global vars */
366 extern const char *tape_state_verbose[];
367 extern const char *tape_op_verbose[];
368 
369 #endif /* for ifdef tape.h */
370