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
tape_do_io_free(struct tape_device * device,struct tape_request * request)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
tape_do_io_async_free(struct tape_device * device,struct tape_request * request)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
tape_proc_init(void)287  static inline void tape_proc_init (void) {;}
tape_proc_cleanup(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 *
tape_ccw_cc(struct ccw1 * ccw,__u8 cmd_code,__u16 memsize,void * cda)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 *
tape_ccw_end(struct ccw1 * ccw,__u8 cmd_code,__u16 memsize,void * cda)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 *
tape_ccw_cmd(struct ccw1 * ccw,__u8 cmd_code)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 *
tape_ccw_repeat(struct ccw1 * ccw,__u8 cmd_code,int count)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 *
tape_ccw_cc_idal(struct ccw1 * ccw,__u8 cmd_code,struct idal_buffer * idal)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 *
tape_ccw_end_idal(struct ccw1 * ccw,__u8 cmd_code,struct idal_buffer * idal)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