xref: /openbmc/linux/drivers/s390/block/dasd_int.h (revision a06c488d)
1 /*
2  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
3  *		    Horst Hummel <Horst.Hummel@de.ibm.com>
4  *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
5  * Bugreports.to..: <Linux390@de.ibm.com>
6  * Copyright IBM Corp. 1999, 2009
7  */
8 
9 #ifndef DASD_INT_H
10 #define DASD_INT_H
11 
12 /* we keep old device allocation scheme; IOW, minors are still in 0..255 */
13 #define DASD_PER_MAJOR (1U << (MINORBITS - DASD_PARTN_BITS))
14 #define DASD_PARTN_MASK ((1 << DASD_PARTN_BITS) - 1)
15 
16 /*
17  * States a dasd device can have:
18  *   new: the dasd_device structure is allocated.
19  *   known: the discipline for the device is identified.
20  *   basic: the device can do basic i/o.
21  *   unfmt: the device could not be analyzed (format is unknown).
22  *   ready: partition detection is done and the device is can do block io.
23  *   online: the device accepts requests from the block device queue.
24  *
25  * Things to do for startup state transitions:
26  *   new -> known: find discipline for the device and create devfs entries.
27  *   known -> basic: request irq line for the device.
28  *   basic -> ready: do the initial analysis, e.g. format detection,
29  *                   do block device setup and detect partitions.
30  *   ready -> online: schedule the device tasklet.
31  * Things to do for shutdown state transitions:
32  *   online -> ready: just set the new device state.
33  *   ready -> basic: flush requests from the block device layer, clear
34  *                   partition information and reset format information.
35  *   basic -> known: terminate all requests and free irq.
36  *   known -> new: remove devfs entries and forget discipline.
37  */
38 
39 #define DASD_STATE_NEW	  0
40 #define DASD_STATE_KNOWN  1
41 #define DASD_STATE_BASIC  2
42 #define DASD_STATE_UNFMT  3
43 #define DASD_STATE_READY  4
44 #define DASD_STATE_ONLINE 5
45 
46 #include <linux/module.h>
47 #include <linux/wait.h>
48 #include <linux/blkdev.h>
49 #include <linux/genhd.h>
50 #include <linux/hdreg.h>
51 #include <linux/interrupt.h>
52 #include <linux/log2.h>
53 #include <asm/ccwdev.h>
54 #include <linux/workqueue.h>
55 #include <asm/debug.h>
56 #include <asm/dasd.h>
57 #include <asm/idals.h>
58 
59 /* DASD discipline magic */
60 #define DASD_ECKD_MAGIC 0xC5C3D2C4
61 #define DASD_DIAG_MAGIC 0xC4C9C1C7
62 #define DASD_FBA_MAGIC 0xC6C2C140
63 
64 /*
65  * SECTION: Type definitions
66  */
67 struct dasd_device;
68 struct dasd_block;
69 
70 /* BIT DEFINITIONS FOR SENSE DATA */
71 #define DASD_SENSE_BIT_0 0x80
72 #define DASD_SENSE_BIT_1 0x40
73 #define DASD_SENSE_BIT_2 0x20
74 #define DASD_SENSE_BIT_3 0x10
75 
76 /* BIT DEFINITIONS FOR SIM SENSE */
77 #define DASD_SIM_SENSE 0x0F
78 #define DASD_SIM_MSG_TO_OP 0x03
79 #define DASD_SIM_LOG 0x0C
80 
81 /* lock class for nested cdev lock */
82 #define CDEV_NESTED_FIRST 1
83 #define CDEV_NESTED_SECOND 2
84 
85 /*
86  * SECTION: MACROs for klogd and s390 debug feature (dbf)
87  */
88 #define DBF_DEV_EVENT(d_level, d_device, d_str, d_data...) \
89 do { \
90 	debug_sprintf_event(d_device->debug_area, \
91 			    d_level, \
92 			    d_str "\n", \
93 			    d_data); \
94 } while(0)
95 
96 #define DBF_DEV_EXC(d_level, d_device, d_str, d_data...) \
97 do { \
98 	debug_sprintf_exception(d_device->debug_area, \
99 				d_level, \
100 				d_str "\n", \
101 				d_data); \
102 } while(0)
103 
104 #define DBF_EVENT(d_level, d_str, d_data...)\
105 do { \
106 	debug_sprintf_event(dasd_debug_area, \
107 			    d_level,\
108 			    d_str "\n", \
109 			    d_data); \
110 } while(0)
111 
112 #define DBF_EVENT_DEVID(d_level, d_cdev, d_str, d_data...)	\
113 do { \
114 	struct ccw_dev_id __dev_id;			\
115 	ccw_device_get_id(d_cdev, &__dev_id);		\
116 	debug_sprintf_event(dasd_debug_area,		\
117 			    d_level,					\
118 			    "0.%x.%04x " d_str "\n",			\
119 			    __dev_id.ssid, __dev_id.devno, d_data);	\
120 } while (0)
121 
122 #define DBF_EXC(d_level, d_str, d_data...)\
123 do { \
124 	debug_sprintf_exception(dasd_debug_area, \
125 				d_level,\
126 				d_str "\n", \
127 				d_data); \
128 } while(0)
129 
130 /* limit size for an errorstring */
131 #define ERRORLENGTH 30
132 
133 /* definition of dbf debug levels */
134 #define	DBF_EMERG	0	/* system is unusable			*/
135 #define	DBF_ALERT	1	/* action must be taken immediately	*/
136 #define	DBF_CRIT	2	/* critical conditions			*/
137 #define	DBF_ERR		3	/* error conditions			*/
138 #define	DBF_WARNING	4	/* warning conditions			*/
139 #define	DBF_NOTICE	5	/* normal but significant condition	*/
140 #define	DBF_INFO	6	/* informational			*/
141 #define	DBF_DEBUG	6	/* debug-level messages			*/
142 
143 /* messages to be written via klogd and dbf */
144 #define DEV_MESSAGE(d_loglevel,d_device,d_string,d_args...)\
145 do { \
146 	printk(d_loglevel PRINTK_HEADER " %s: " d_string "\n", \
147 	       dev_name(&d_device->cdev->dev), d_args); \
148 	DBF_DEV_EVENT(DBF_ALERT, d_device, d_string, d_args); \
149 } while(0)
150 
151 #define MESSAGE(d_loglevel,d_string,d_args...)\
152 do { \
153 	printk(d_loglevel PRINTK_HEADER " " d_string "\n", d_args); \
154 	DBF_EVENT(DBF_ALERT, d_string, d_args); \
155 } while(0)
156 
157 /* messages to be written via klogd only */
158 #define DEV_MESSAGE_LOG(d_loglevel,d_device,d_string,d_args...)\
159 do { \
160 	printk(d_loglevel PRINTK_HEADER " %s: " d_string "\n", \
161 	       dev_name(&d_device->cdev->dev), d_args); \
162 } while(0)
163 
164 #define MESSAGE_LOG(d_loglevel,d_string,d_args...)\
165 do { \
166 	printk(d_loglevel PRINTK_HEADER " " d_string "\n", d_args); \
167 } while(0)
168 
169 struct dasd_ccw_req {
170 	unsigned int magic;		/* Eye catcher */
171 	struct list_head devlist;	/* for dasd_device request queue */
172 	struct list_head blocklist;	/* for dasd_block request queue */
173 
174 	/* Where to execute what... */
175 	struct dasd_block *block;	/* the originating block device */
176 	struct dasd_device *memdev;	/* the device used to allocate this */
177 	struct dasd_device *startdev;	/* device the request is started on */
178 	struct dasd_device *basedev;	/* base device if no block->base */
179 	void *cpaddr;			/* address of ccw or tcw */
180 	unsigned char cpmode;		/* 0 = cmd mode, 1 = itcw */
181 	char status;			/* status of this request */
182 	short retries;			/* A retry counter */
183 	unsigned long flags;        	/* flags of this request */
184 
185 	/* ... and how */
186 	unsigned long starttime;	/* jiffies time of request start */
187 	unsigned long expires;		/* expiration period in jiffies */
188 	char lpm;			/* logical path mask */
189 	void *data;			/* pointer to data area */
190 
191 	/* these are important for recovering erroneous requests          */
192 	int intrc;			/* internal error, e.g. from start_IO */
193 	struct irb irb;			/* device status in case of an error */
194 	struct dasd_ccw_req *refers;	/* ERP-chain queueing. */
195 	void *function; 		/* originating ERP action */
196 
197 	/* these are for statistics only */
198 	unsigned long long buildclk;	/* TOD-clock of request generation */
199 	unsigned long long startclk;	/* TOD-clock of request start */
200 	unsigned long long stopclk;	/* TOD-clock of request interrupt */
201 	unsigned long long endclk;	/* TOD-clock of request termination */
202 
203         /* Callback that is called after reaching final status. */
204 	void (*callback)(struct dasd_ccw_req *, void *data);
205 	void *callback_data;
206 };
207 
208 /*
209  * dasd_ccw_req -> status can be:
210  */
211 #define DASD_CQR_FILLED 	0x00	/* request is ready to be processed */
212 #define DASD_CQR_DONE		0x01	/* request is completed successfully */
213 #define DASD_CQR_NEED_ERP	0x02	/* request needs recovery action */
214 #define DASD_CQR_IN_ERP 	0x03	/* request is in recovery */
215 #define DASD_CQR_FAILED 	0x04	/* request is finally failed */
216 #define DASD_CQR_TERMINATED	0x05	/* request was stopped by driver */
217 
218 #define DASD_CQR_QUEUED 	0x80	/* request is queued to be processed */
219 #define DASD_CQR_IN_IO		0x81	/* request is currently in IO */
220 #define DASD_CQR_ERROR		0x82	/* request is completed with error */
221 #define DASD_CQR_CLEAR_PENDING	0x83	/* request is clear pending */
222 #define DASD_CQR_CLEARED	0x84	/* request was cleared */
223 #define DASD_CQR_SUCCESS	0x85	/* request was successful */
224 
225 /* default expiration time*/
226 #define DASD_EXPIRES	  300
227 #define DASD_EXPIRES_MAX  40000000
228 #define DASD_RETRIES	  256
229 #define DASD_RETRIES_MAX  32768
230 
231 /* per dasd_ccw_req flags */
232 #define DASD_CQR_FLAGS_USE_ERP   0	/* use ERP for this request */
233 #define DASD_CQR_FLAGS_FAILFAST  1	/* FAILFAST */
234 #define DASD_CQR_VERIFY_PATH	 2	/* path verification request */
235 #define DASD_CQR_ALLOW_SLOCK	 3	/* Try this request even when lock was
236 					 * stolen. Should not be combined with
237 					 * DASD_CQR_FLAGS_USE_ERP
238 					 */
239 
240 /* Signature for error recovery functions. */
241 typedef struct dasd_ccw_req *(*dasd_erp_fn_t) (struct dasd_ccw_req *);
242 
243 /*
244  * Unique identifier for dasd device.
245  */
246 #define UA_NOT_CONFIGURED  0x00
247 #define UA_BASE_DEVICE	   0x01
248 #define UA_BASE_PAV_ALIAS  0x02
249 #define UA_HYPER_PAV_ALIAS 0x03
250 
251 struct dasd_uid {
252 	__u8 type;
253 	char vendor[4];
254 	char serial[15];
255 	__u16 ssid;
256 	__u8 real_unit_addr;
257 	__u8 base_unit_addr;
258 	char vduit[33];
259 };
260 
261 /*
262  * the struct dasd_discipline is
263  * sth like a table of virtual functions, if you think of dasd_eckd
264  * inheriting dasd...
265  * no, currently we are not planning to reimplement the driver in C++
266  */
267 struct dasd_discipline {
268 	struct module *owner;
269 	char ebcname[8];	/* a name used for tagging and printks */
270 	char name[8];		/* a name used for tagging and printks */
271 	int max_blocks;		/* maximum number of blocks to be chained */
272 
273 	struct list_head list;	/* used for list of disciplines */
274 
275 	/*
276 	 * Device recognition functions. check_device is used to verify
277 	 * the sense data and the information returned by read device
278 	 * characteristics. It returns 0 if the discipline can be used
279 	 * for the device in question. uncheck_device is called during
280 	 * device shutdown to deregister a device from its discipline.
281 	 */
282 	int (*check_device) (struct dasd_device *);
283 	void (*uncheck_device) (struct dasd_device *);
284 
285 	/*
286 	 * do_analysis is used in the step from device state "basic" to
287 	 * state "accept". It returns 0 if the device can be made ready,
288 	 * it returns -EMEDIUMTYPE if the device can't be made ready or
289 	 * -EAGAIN if do_analysis started a ccw that needs to complete
290 	 * before the analysis may be repeated.
291 	 */
292 	int (*do_analysis) (struct dasd_block *);
293 
294 	/*
295 	 * This function is called, when new paths become available.
296 	 * Disciplins may use this callback to do necessary setup work,
297 	 * e.g. verify that new path is compatible with the current
298 	 * configuration.
299 	 */
300 	int (*verify_path)(struct dasd_device *, __u8);
301 
302 	/*
303 	 * Last things to do when a device is set online, and first things
304 	 * when it is set offline.
305 	 */
306 	int (*basic_to_ready) (struct dasd_device *);
307 	int (*online_to_ready) (struct dasd_device *);
308 	int (*basic_to_known)(struct dasd_device *);
309 
310 	/* (struct dasd_device *);
311 	 * Device operation functions. build_cp creates a ccw chain for
312 	 * a block device request, start_io starts the request and
313 	 * term_IO cancels it (e.g. in case of a timeout). format_device
314 	 * returns a ccw chain to be used to format the device.
315 	 * handle_terminated_request allows to examine a cqr and prepare
316 	 * it for retry.
317 	 */
318 	struct dasd_ccw_req *(*build_cp) (struct dasd_device *,
319 					  struct dasd_block *,
320 					  struct request *);
321 	int (*start_IO) (struct dasd_ccw_req *);
322 	int (*term_IO) (struct dasd_ccw_req *);
323 	void (*handle_terminated_request) (struct dasd_ccw_req *);
324 	int (*format_device) (struct dasd_device *,
325 			      struct format_data_t *, int enable_pav);
326 	int (*free_cp) (struct dasd_ccw_req *, struct request *);
327 
328 	/*
329 	 * Error recovery functions. examine_error() returns a value that
330 	 * indicates what to do for an error condition. If examine_error()
331 	 * returns 'dasd_era_recover' erp_action() is called to create a
332 	 * special error recovery ccw. erp_postaction() is called after
333 	 * an error recovery ccw has finished its execution. dump_sense
334 	 * is called for every error condition to print the sense data
335 	 * to the console.
336 	 */
337 	dasd_erp_fn_t(*erp_action) (struct dasd_ccw_req *);
338 	dasd_erp_fn_t(*erp_postaction) (struct dasd_ccw_req *);
339 	void (*dump_sense) (struct dasd_device *, struct dasd_ccw_req *,
340 			    struct irb *);
341 	void (*dump_sense_dbf) (struct dasd_device *, struct irb *, char *);
342 	void (*check_for_device_change) (struct dasd_device *,
343 					 struct dasd_ccw_req *,
344 					 struct irb *);
345 
346         /* i/o control functions. */
347 	int (*fill_geometry) (struct dasd_block *, struct hd_geometry *);
348 	int (*fill_info) (struct dasd_device *, struct dasd_information2_t *);
349 	int (*ioctl) (struct dasd_block *, unsigned int, void __user *);
350 
351 	/* suspend/resume functions */
352 	int (*freeze) (struct dasd_device *);
353 	int (*restore) (struct dasd_device *);
354 
355 	/* reload device after state change */
356 	int (*reload) (struct dasd_device *);
357 
358 	int (*get_uid) (struct dasd_device *, struct dasd_uid *);
359 	void (*kick_validate) (struct dasd_device *);
360 	int (*check_attention)(struct dasd_device *, __u8);
361 };
362 
363 extern struct dasd_discipline *dasd_diag_discipline_pointer;
364 
365 /*
366  * Notification numbers for extended error reporting notifications:
367  * The DASD_EER_DISABLE notification is sent before a dasd_device (and it's
368  * eer pointer) is freed. The error reporting module needs to do all necessary
369  * cleanup steps.
370  * The DASD_EER_TRIGGER notification sends the actual error reports (triggers).
371  */
372 #define DASD_EER_DISABLE 0
373 #define DASD_EER_TRIGGER 1
374 
375 /* Trigger IDs for extended error reporting DASD_EER_TRIGGER notification */
376 #define DASD_EER_FATALERROR  1
377 #define DASD_EER_NOPATH      2
378 #define DASD_EER_STATECHANGE 3
379 #define DASD_EER_PPRCSUSPEND 4
380 
381 struct dasd_path {
382 	__u8 opm;
383 	__u8 tbvpm;
384 	__u8 ppm;
385 	__u8 npm;
386 	/* paths that are not used because of a special condition */
387 	__u8 cablepm; /* miss-cabled */
388 	__u8 hpfpm;   /* the HPF requirements of the other paths are not met */
389 	__u8 cuirpm;  /* CUIR varied offline */
390 };
391 
392 struct dasd_profile_info {
393 	/* legacy part of profile data, as in dasd_profile_info_t */
394 	unsigned int dasd_io_reqs;	 /* number of requests processed */
395 	unsigned int dasd_io_sects;	 /* number of sectors processed */
396 	unsigned int dasd_io_secs[32];	 /* histogram of request's sizes */
397 	unsigned int dasd_io_times[32];	 /* histogram of requests's times */
398 	unsigned int dasd_io_timps[32];	 /* h. of requests's times per sector */
399 	unsigned int dasd_io_time1[32];	 /* hist. of time from build to start */
400 	unsigned int dasd_io_time2[32];	 /* hist. of time from start to irq */
401 	unsigned int dasd_io_time2ps[32]; /* hist. of time from start to irq */
402 	unsigned int dasd_io_time3[32];	 /* hist. of time from irq to end */
403 	unsigned int dasd_io_nr_req[32]; /* hist. of # of requests in chanq */
404 
405 	/* new data */
406 	struct timespec starttod;	   /* time of start or last reset */
407 	unsigned int dasd_io_alias;	   /* requests using an alias */
408 	unsigned int dasd_io_tpm;	   /* requests using transport mode */
409 	unsigned int dasd_read_reqs;	   /* total number of read  requests */
410 	unsigned int dasd_read_sects;	   /* total number read sectors */
411 	unsigned int dasd_read_alias;	   /* read request using an alias */
412 	unsigned int dasd_read_tpm;	   /* read requests in transport mode */
413 	unsigned int dasd_read_secs[32];   /* histogram of request's sizes */
414 	unsigned int dasd_read_times[32];  /* histogram of requests's times */
415 	unsigned int dasd_read_time1[32];  /* hist. time from build to start */
416 	unsigned int dasd_read_time2[32];  /* hist. of time from start to irq */
417 	unsigned int dasd_read_time3[32];  /* hist. of time from irq to end */
418 	unsigned int dasd_read_nr_req[32]; /* hist. of # of requests in chanq */
419 };
420 
421 struct dasd_profile {
422 	struct dentry *dentry;
423 	struct dasd_profile_info *data;
424 	spinlock_t lock;
425 };
426 
427 struct dasd_device {
428 	/* Block device stuff. */
429 	struct dasd_block *block;
430 
431         unsigned int devindex;
432 	unsigned long flags;	   /* per device flags */
433 	unsigned short features;   /* copy of devmap-features (read-only!) */
434 
435 	/* extended error reporting stuff (eer) */
436 	struct dasd_ccw_req *eer_cqr;
437 
438 	/* Device discipline stuff. */
439 	struct dasd_discipline *discipline;
440 	struct dasd_discipline *base_discipline;
441 	char *private;
442 	struct dasd_path path_data;
443 
444 	/* Device state and target state. */
445 	int state, target;
446 	struct mutex state_mutex;
447 	int stopped;		/* device (ccw_device_start) was stopped */
448 
449 	/* reference count. */
450         atomic_t ref_count;
451 
452 	/* ccw queue and memory for static ccw/erp buffers. */
453 	struct list_head ccw_queue;
454 	spinlock_t mem_lock;
455 	void *ccw_mem;
456 	void *erp_mem;
457 	struct list_head ccw_chunks;
458 	struct list_head erp_chunks;
459 
460 	atomic_t tasklet_scheduled;
461         struct tasklet_struct tasklet;
462 	struct work_struct kick_work;
463 	struct work_struct restore_device;
464 	struct work_struct reload_device;
465 	struct work_struct kick_validate;
466 	struct timer_list timer;
467 
468 	debug_info_t *debug_area;
469 
470 	struct ccw_device *cdev;
471 
472 	/* hook for alias management */
473 	struct list_head alias_list;
474 
475 	/* default expiration time in s */
476 	unsigned long default_expires;
477 	unsigned long default_retries;
478 
479 	unsigned long blk_timeout;
480 
481 	struct dentry *debugfs_dentry;
482 	struct dasd_profile profile;
483 };
484 
485 struct dasd_block {
486 	/* Block device stuff. */
487 	struct gendisk *gdp;
488 	struct request_queue *request_queue;
489 	spinlock_t request_queue_lock;
490 	struct block_device *bdev;
491 	atomic_t open_count;
492 
493 	unsigned long long blocks; /* size of volume in blocks */
494 	unsigned int bp_block;	   /* bytes per block */
495 	unsigned int s2b_shift;	   /* log2 (bp_block/512) */
496 
497 	struct dasd_device *base;
498 	struct list_head ccw_queue;
499 	spinlock_t queue_lock;
500 
501 	atomic_t tasklet_scheduled;
502 	struct tasklet_struct tasklet;
503 	struct timer_list timer;
504 
505 	struct dentry *debugfs_dentry;
506 	struct dasd_profile profile;
507 };
508 
509 struct dasd_attention_data {
510 	struct dasd_device *device;
511 	__u8 lpum;
512 };
513 
514 /* reasons why device (ccw_device_start) was stopped */
515 #define DASD_STOPPED_NOT_ACC 1         /* not accessible */
516 #define DASD_STOPPED_QUIESCE 2         /* Quiesced */
517 #define DASD_STOPPED_PENDING 4         /* long busy */
518 #define DASD_STOPPED_DC_WAIT 8         /* disconnected, wait */
519 #define DASD_STOPPED_SU      16        /* summary unit check handling */
520 #define DASD_STOPPED_PM      32        /* pm state transition */
521 #define DASD_UNRESUMED_PM    64        /* pm resume failed state */
522 
523 /* per device flags */
524 #define DASD_FLAG_OFFLINE	3	/* device is in offline processing */
525 #define DASD_FLAG_EER_SNSS	4	/* A SNSS is required */
526 #define DASD_FLAG_EER_IN_USE	5	/* A SNSS request is running */
527 #define DASD_FLAG_DEVICE_RO	6	/* The device itself is read-only. Don't
528 					 * confuse this with the user specified
529 					 * read-only feature.
530 					 */
531 #define DASD_FLAG_IS_RESERVED	7	/* The device is reserved */
532 #define DASD_FLAG_LOCK_STOLEN	8	/* The device lock was stolen */
533 #define DASD_FLAG_SUSPENDED	9	/* The device was suspended */
534 #define DASD_FLAG_SAFE_OFFLINE	10	/* safe offline processing requested*/
535 #define DASD_FLAG_SAFE_OFFLINE_RUNNING	11	/* safe offline running */
536 #define DASD_FLAG_ABORTALL	12	/* Abort all noretry requests */
537 #define DASD_FLAG_PATH_VERIFY	13	/* Path verification worker running */
538 
539 #define DASD_SLEEPON_START_TAG	((void *) 1)
540 #define DASD_SLEEPON_END_TAG	((void *) 2)
541 
542 void dasd_put_device_wake(struct dasd_device *);
543 
544 /*
545  * Reference count inliners
546  */
547 static inline void
548 dasd_get_device(struct dasd_device *device)
549 {
550 	atomic_inc(&device->ref_count);
551 }
552 
553 static inline void
554 dasd_put_device(struct dasd_device *device)
555 {
556 	if (atomic_dec_return(&device->ref_count) == 0)
557 		dasd_put_device_wake(device);
558 }
559 
560 /*
561  * The static memory in ccw_mem and erp_mem is managed by a sorted
562  * list of free memory chunks.
563  */
564 struct dasd_mchunk
565 {
566 	struct list_head list;
567 	unsigned long size;
568 } __attribute__ ((aligned(8)));
569 
570 static inline void
571 dasd_init_chunklist(struct list_head *chunk_list, void *mem,
572 		    unsigned long size)
573 {
574 	struct dasd_mchunk *chunk;
575 
576 	INIT_LIST_HEAD(chunk_list);
577 	chunk = (struct dasd_mchunk *) mem;
578 	chunk->size = size - sizeof(struct dasd_mchunk);
579 	list_add(&chunk->list, chunk_list);
580 }
581 
582 static inline void *
583 dasd_alloc_chunk(struct list_head *chunk_list, unsigned long size)
584 {
585 	struct dasd_mchunk *chunk, *tmp;
586 
587 	size = (size + 7L) & -8L;
588 	list_for_each_entry(chunk, chunk_list, list) {
589 		if (chunk->size < size)
590 			continue;
591 		if (chunk->size > size + sizeof(struct dasd_mchunk)) {
592 			char *endaddr = (char *) (chunk + 1) + chunk->size;
593 			tmp = (struct dasd_mchunk *) (endaddr - size) - 1;
594 			tmp->size = size;
595 			chunk->size -= size + sizeof(struct dasd_mchunk);
596 			chunk = tmp;
597 		} else
598 			list_del(&chunk->list);
599 		return (void *) (chunk + 1);
600 	}
601 	return NULL;
602 }
603 
604 static inline void
605 dasd_free_chunk(struct list_head *chunk_list, void *mem)
606 {
607 	struct dasd_mchunk *chunk, *tmp;
608 	struct list_head *p, *left;
609 
610 	chunk = (struct dasd_mchunk *)
611 		((char *) mem - sizeof(struct dasd_mchunk));
612 	/* Find out the left neighbour in chunk_list. */
613 	left = chunk_list;
614 	list_for_each(p, chunk_list) {
615 		if (list_entry(p, struct dasd_mchunk, list) > chunk)
616 			break;
617 		left = p;
618 	}
619 	/* Try to merge with right neighbour = next element from left. */
620 	if (left->next != chunk_list) {
621 		tmp = list_entry(left->next, struct dasd_mchunk, list);
622 		if ((char *) (chunk + 1) + chunk->size == (char *) tmp) {
623 			list_del(&tmp->list);
624 			chunk->size += tmp->size + sizeof(struct dasd_mchunk);
625 		}
626 	}
627 	/* Try to merge with left neighbour. */
628 	if (left != chunk_list) {
629 		tmp = list_entry(left, struct dasd_mchunk, list);
630 		if ((char *) (tmp + 1) + tmp->size == (char *) chunk) {
631 			tmp->size += chunk->size + sizeof(struct dasd_mchunk);
632 			return;
633 		}
634 	}
635 	__list_add(&chunk->list, left, left->next);
636 }
637 
638 /*
639  * Check if bsize is in { 512, 1024, 2048, 4096 }
640  */
641 static inline int
642 dasd_check_blocksize(int bsize)
643 {
644 	if (bsize < 512 || bsize > 4096 || !is_power_of_2(bsize))
645 		return -EMEDIUMTYPE;
646 	return 0;
647 }
648 
649 /* externals in dasd.c */
650 #define DASD_PROFILE_OFF	 0
651 #define DASD_PROFILE_ON 	 1
652 #define DASD_PROFILE_GLOBAL_ONLY 2
653 
654 extern debug_info_t *dasd_debug_area;
655 extern struct dasd_profile dasd_global_profile;
656 extern unsigned int dasd_global_profile_level;
657 extern const struct block_device_operations dasd_device_operations;
658 
659 extern struct kmem_cache *dasd_page_cache;
660 
661 struct dasd_ccw_req *
662 dasd_kmalloc_request(int , int, int, struct dasd_device *);
663 struct dasd_ccw_req *
664 dasd_smalloc_request(int , int, int, struct dasd_device *);
665 void dasd_kfree_request(struct dasd_ccw_req *, struct dasd_device *);
666 void dasd_sfree_request(struct dasd_ccw_req *, struct dasd_device *);
667 void dasd_wakeup_cb(struct dasd_ccw_req *, void *);
668 
669 static inline int
670 dasd_kmalloc_set_cda(struct ccw1 *ccw, void *cda, struct dasd_device *device)
671 {
672 	return set_normalized_cda(ccw, cda);
673 }
674 
675 struct dasd_device *dasd_alloc_device(void);
676 void dasd_free_device(struct dasd_device *);
677 
678 struct dasd_block *dasd_alloc_block(void);
679 void dasd_free_block(struct dasd_block *);
680 
681 enum blk_eh_timer_return dasd_times_out(struct request *req);
682 
683 void dasd_enable_device(struct dasd_device *);
684 void dasd_set_target_state(struct dasd_device *, int);
685 void dasd_kick_device(struct dasd_device *);
686 void dasd_restore_device(struct dasd_device *);
687 void dasd_reload_device(struct dasd_device *);
688 
689 void dasd_add_request_head(struct dasd_ccw_req *);
690 void dasd_add_request_tail(struct dasd_ccw_req *);
691 int  dasd_start_IO(struct dasd_ccw_req *);
692 int  dasd_term_IO(struct dasd_ccw_req *);
693 void dasd_schedule_device_bh(struct dasd_device *);
694 void dasd_schedule_block_bh(struct dasd_block *);
695 int  dasd_sleep_on(struct dasd_ccw_req *);
696 int  dasd_sleep_on_queue(struct list_head *);
697 int  dasd_sleep_on_immediatly(struct dasd_ccw_req *);
698 int  dasd_sleep_on_interruptible(struct dasd_ccw_req *);
699 void dasd_device_set_timer(struct dasd_device *, int);
700 void dasd_device_clear_timer(struct dasd_device *);
701 void dasd_block_set_timer(struct dasd_block *, int);
702 void dasd_block_clear_timer(struct dasd_block *);
703 int  dasd_cancel_req(struct dasd_ccw_req *);
704 int dasd_flush_device_queue(struct dasd_device *);
705 int dasd_generic_probe (struct ccw_device *, struct dasd_discipline *);
706 void dasd_generic_remove (struct ccw_device *cdev);
707 int dasd_generic_set_online(struct ccw_device *, struct dasd_discipline *);
708 int dasd_generic_set_offline (struct ccw_device *cdev);
709 int dasd_generic_notify(struct ccw_device *, int);
710 int dasd_generic_last_path_gone(struct dasd_device *);
711 int dasd_generic_path_operational(struct dasd_device *);
712 void dasd_generic_shutdown(struct ccw_device *);
713 
714 void dasd_generic_handle_state_change(struct dasd_device *);
715 int dasd_generic_pm_freeze(struct ccw_device *);
716 int dasd_generic_restore_device(struct ccw_device *);
717 enum uc_todo dasd_generic_uc_handler(struct ccw_device *, struct irb *);
718 void dasd_generic_path_event(struct ccw_device *, int *);
719 int dasd_generic_verify_path(struct dasd_device *, __u8);
720 
721 int dasd_generic_read_dev_chars(struct dasd_device *, int, void *, int);
722 char *dasd_get_sense(struct irb *);
723 
724 void dasd_device_set_stop_bits(struct dasd_device *, int);
725 void dasd_device_remove_stop_bits(struct dasd_device *, int);
726 
727 int dasd_device_is_ro(struct dasd_device *);
728 
729 void dasd_profile_reset(struct dasd_profile *);
730 int dasd_profile_on(struct dasd_profile *);
731 void dasd_profile_off(struct dasd_profile *);
732 char *dasd_get_user_string(const char __user *, size_t);
733 
734 /* externals in dasd_devmap.c */
735 extern int dasd_max_devindex;
736 extern int dasd_probeonly;
737 extern int dasd_autodetect;
738 extern int dasd_nopav;
739 extern int dasd_nofcx;
740 
741 int dasd_devmap_init(void);
742 void dasd_devmap_exit(void);
743 
744 struct dasd_device *dasd_create_device(struct ccw_device *);
745 void dasd_delete_device(struct dasd_device *);
746 
747 int dasd_get_feature(struct ccw_device *, int);
748 int dasd_set_feature(struct ccw_device *, int, int);
749 
750 int dasd_add_sysfs_files(struct ccw_device *);
751 void dasd_remove_sysfs_files(struct ccw_device *);
752 
753 struct dasd_device *dasd_device_from_cdev(struct ccw_device *);
754 struct dasd_device *dasd_device_from_cdev_locked(struct ccw_device *);
755 struct dasd_device *dasd_device_from_devindex(int);
756 
757 void dasd_add_link_to_gendisk(struct gendisk *, struct dasd_device *);
758 struct dasd_device *dasd_device_from_gendisk(struct gendisk *);
759 
760 int dasd_parse(void);
761 int dasd_busid_known(const char *);
762 
763 /* externals in dasd_gendisk.c */
764 int  dasd_gendisk_init(void);
765 void dasd_gendisk_exit(void);
766 int dasd_gendisk_alloc(struct dasd_block *);
767 void dasd_gendisk_free(struct dasd_block *);
768 int dasd_scan_partitions(struct dasd_block *);
769 void dasd_destroy_partitions(struct dasd_block *);
770 
771 /* externals in dasd_ioctl.c */
772 int  dasd_ioctl(struct block_device *, fmode_t, unsigned int, unsigned long);
773 
774 /* externals in dasd_proc.c */
775 int dasd_proc_init(void);
776 void dasd_proc_exit(void);
777 
778 /* externals in dasd_erp.c */
779 struct dasd_ccw_req *dasd_default_erp_action(struct dasd_ccw_req *);
780 struct dasd_ccw_req *dasd_default_erp_postaction(struct dasd_ccw_req *);
781 struct dasd_ccw_req *dasd_alloc_erp_request(char *, int, int,
782 					    struct dasd_device *);
783 void dasd_free_erp_request(struct dasd_ccw_req *, struct dasd_device *);
784 void dasd_log_sense(struct dasd_ccw_req *, struct irb *);
785 void dasd_log_sense_dbf(struct dasd_ccw_req *cqr, struct irb *irb);
786 
787 /* externals in dasd_3990_erp.c */
788 struct dasd_ccw_req *dasd_3990_erp_action(struct dasd_ccw_req *);
789 void dasd_3990_erp_handle_sim(struct dasd_device *, char *);
790 
791 /* externals in dasd_eer.c */
792 #ifdef CONFIG_DASD_EER
793 int dasd_eer_init(void);
794 void dasd_eer_exit(void);
795 int dasd_eer_enable(struct dasd_device *);
796 void dasd_eer_disable(struct dasd_device *);
797 void dasd_eer_write(struct dasd_device *, struct dasd_ccw_req *cqr,
798 		    unsigned int id);
799 void dasd_eer_snss(struct dasd_device *);
800 
801 static inline int dasd_eer_enabled(struct dasd_device *device)
802 {
803 	return device->eer_cqr != NULL;
804 }
805 #else
806 #define dasd_eer_init()		(0)
807 #define dasd_eer_exit()		do { } while (0)
808 #define dasd_eer_enable(d)	(0)
809 #define dasd_eer_disable(d)	do { } while (0)
810 #define dasd_eer_write(d,c,i)	do { } while (0)
811 #define dasd_eer_snss(d)	do { } while (0)
812 #define dasd_eer_enabled(d)	(0)
813 #endif	/* CONFIG_DASD_ERR */
814 
815 #endif				/* DASD_H */
816