xref: /openbmc/linux/drivers/s390/char/tape.h (revision 2cf1c348)
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 
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 	/* 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 #define TAPE_IO_LONG_BUSY	4	/* delay the running request */
172 
173 /* Char Frontend Data */
174 struct tape_char_data {
175 	struct idal_buffer *idal_buf;	/* idal buffer for user char data */
176 	int block_size;			/*   of size block_size. */
177 };
178 
179 /* Tape Info */
180 struct tape_device {
181 	/* entry in tape_device_list */
182 	struct list_head		node;
183 
184 	int				cdev_id;
185 	struct ccw_device *		cdev;
186 	struct tape_class_device *	nt;
187 	struct tape_class_device *	rt;
188 
189 	/* Device mutex to serialize tape commands. */
190 	struct mutex			mutex;
191 
192 	/* Device discipline information. */
193 	struct tape_discipline *	discipline;
194 	void *				discdata;
195 
196 	/* Generic status flags */
197 	long				tape_generic_status;
198 
199 	/* Device state information. */
200 	wait_queue_head_t		state_change_wq;
201 	enum tape_state			tape_state;
202 	enum tape_medium_state		medium_state;
203 	unsigned char *			modeset_byte;
204 
205 	/* Reference count. */
206 	atomic_t			ref_count;
207 
208 	/* Request queue. */
209 	struct list_head		req_queue;
210 
211 	/* Request wait queue. */
212 	wait_queue_head_t		wait_queue;
213 
214 	/* Each tape device has (currently) two minor numbers. */
215 	int				first_minor;
216 
217 	/* Number of tapemarks required for correct termination. */
218 	int				required_tapemarks;
219 
220 	/* Block ID of the BOF */
221 	unsigned int			bof;
222 
223 	/* Character device frontend data */
224 	struct tape_char_data		char_data;
225 
226 	/* Function to start or stop the next request later. */
227 	struct delayed_work		tape_dnr;
228 
229 	/* Timer for long busy */
230 	struct timer_list		lb_timeout;
231 
232 };
233 
234 /* Externals from tape_core.c */
235 extern struct tape_request *tape_alloc_request(int cplength, int datasize);
236 extern void tape_free_request(struct tape_request *);
237 extern int tape_do_io(struct tape_device *, struct tape_request *);
238 extern int tape_do_io_async(struct tape_device *, struct tape_request *);
239 extern int tape_do_io_interruptible(struct tape_device *, struct tape_request *);
240 extern int tape_cancel_io(struct tape_device *, struct tape_request *);
241 
242 static inline int
243 tape_do_io_free(struct tape_device *device, struct tape_request *request)
244 {
245 	int rc;
246 
247 	rc = tape_do_io(device, request);
248 	tape_free_request(request);
249 	return rc;
250 }
251 
252 static inline void
253 tape_do_io_async_free(struct tape_device *device, struct tape_request *request)
254 {
255 	request->callback = (void *) tape_free_request;
256 	request->callback_data = NULL;
257 	tape_do_io_async(device, request);
258 }
259 
260 extern int tape_open(struct tape_device *);
261 extern int tape_release(struct tape_device *);
262 extern int tape_mtop(struct tape_device *, int, int);
263 extern void tape_state_set(struct tape_device *, enum tape_state);
264 
265 extern int tape_generic_online(struct tape_device *, struct tape_discipline *);
266 extern int tape_generic_offline(struct ccw_device *);
267 
268 /* Externals from tape_devmap.c */
269 extern int tape_generic_probe(struct ccw_device *);
270 extern void tape_generic_remove(struct ccw_device *);
271 
272 extern struct tape_device *tape_find_device(int devindex);
273 extern struct tape_device *tape_get_device(struct tape_device *);
274 extern void tape_put_device(struct tape_device *);
275 
276 /* Externals from tape_char.c */
277 extern int tapechar_init(void);
278 extern void tapechar_exit(void);
279 extern int  tapechar_setup_device(struct tape_device *);
280 extern void tapechar_cleanup_device(struct tape_device *);
281 
282 /* tape initialisation functions */
283 #ifdef CONFIG_PROC_FS
284 extern void tape_proc_init (void);
285 extern void tape_proc_cleanup (void);
286 #else
287 static inline void tape_proc_init (void) {;}
288 static inline void tape_proc_cleanup (void) {;}
289 #endif
290 
291 /* a function for dumping device sense info */
292 extern void tape_dump_sense_dbf(struct tape_device *, struct tape_request *,
293 				struct irb *);
294 
295 /* functions for handling the status of a device */
296 extern void tape_med_state_set(struct tape_device *, enum tape_medium_state);
297 
298 /* The debug area */
299 extern debug_info_t *TAPE_DBF_AREA;
300 
301 /* functions for building ccws */
302 static inline struct ccw1 *
303 tape_ccw_cc(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
304 {
305 	ccw->cmd_code = cmd_code;
306 	ccw->flags = CCW_FLAG_CC;
307 	ccw->count = memsize;
308 	ccw->cda = (__u32)(addr_t) cda;
309 	return ccw + 1;
310 }
311 
312 static inline struct ccw1 *
313 tape_ccw_end(struct ccw1 *ccw, __u8 cmd_code, __u16 memsize, void *cda)
314 {
315 	ccw->cmd_code = cmd_code;
316 	ccw->flags = 0;
317 	ccw->count = memsize;
318 	ccw->cda = (__u32)(addr_t) cda;
319 	return ccw + 1;
320 }
321 
322 static inline struct ccw1 *
323 tape_ccw_cmd(struct ccw1 *ccw, __u8 cmd_code)
324 {
325 	ccw->cmd_code = cmd_code;
326 	ccw->flags = 0;
327 	ccw->count = 0;
328 	ccw->cda = (__u32)(addr_t) &ccw->cmd_code;
329 	return ccw + 1;
330 }
331 
332 static inline struct ccw1 *
333 tape_ccw_repeat(struct ccw1 *ccw, __u8 cmd_code, int count)
334 {
335 	while (count-- > 0) {
336 		ccw->cmd_code = cmd_code;
337 		ccw->flags = CCW_FLAG_CC;
338 		ccw->count = 0;
339 		ccw->cda = (__u32)(addr_t) &ccw->cmd_code;
340 		ccw++;
341 	}
342 	return ccw;
343 }
344 
345 static inline struct ccw1 *
346 tape_ccw_cc_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
347 {
348 	ccw->cmd_code = cmd_code;
349 	ccw->flags    = CCW_FLAG_CC;
350 	idal_buffer_set_cda(idal, ccw);
351 	return ccw++;
352 }
353 
354 static inline struct ccw1 *
355 tape_ccw_end_idal(struct ccw1 *ccw, __u8 cmd_code, struct idal_buffer *idal)
356 {
357 	ccw->cmd_code = cmd_code;
358 	ccw->flags    = 0;
359 	idal_buffer_set_cda(idal, ccw);
360 	return ccw++;
361 }
362 
363 /* Global vars */
364 extern const char *tape_state_verbose[];
365 extern const char *tape_op_verbose[];
366 
367 #endif /* for ifdef tape.h */
368