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 */
67struct dasd_device;
68struct 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...) \
89do { \
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...) \
97do { \
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...)\
105do { \
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...)	\
113do { \
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...)\
123do { \
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...)\
145do { \
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...)\
152do { \
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...)\
159do { \
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...)\
165do { \
166	printk(d_loglevel PRINTK_HEADER " " d_string "\n", d_args); \
167} while(0)
168
169struct 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. */
241typedef 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
251struct 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 */
267struct 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
363extern 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
381struct 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
392struct 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
421struct dasd_profile {
422	struct dentry *dentry;
423	struct dasd_profile_info *data;
424	spinlock_t lock;
425};
426
427struct 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
485struct 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
509struct 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
538#define DASD_SLEEPON_START_TAG	((void *) 1)
539#define DASD_SLEEPON_END_TAG	((void *) 2)
540
541void dasd_put_device_wake(struct dasd_device *);
542
543/*
544 * Reference count inliners
545 */
546static inline void
547dasd_get_device(struct dasd_device *device)
548{
549	atomic_inc(&device->ref_count);
550}
551
552static inline void
553dasd_put_device(struct dasd_device *device)
554{
555	if (atomic_dec_return(&device->ref_count) == 0)
556		dasd_put_device_wake(device);
557}
558
559/*
560 * The static memory in ccw_mem and erp_mem is managed by a sorted
561 * list of free memory chunks.
562 */
563struct dasd_mchunk
564{
565	struct list_head list;
566	unsigned long size;
567} __attribute__ ((aligned(8)));
568
569static inline void
570dasd_init_chunklist(struct list_head *chunk_list, void *mem,
571		    unsigned long size)
572{
573	struct dasd_mchunk *chunk;
574
575	INIT_LIST_HEAD(chunk_list);
576	chunk = (struct dasd_mchunk *) mem;
577	chunk->size = size - sizeof(struct dasd_mchunk);
578	list_add(&chunk->list, chunk_list);
579}
580
581static inline void *
582dasd_alloc_chunk(struct list_head *chunk_list, unsigned long size)
583{
584	struct dasd_mchunk *chunk, *tmp;
585
586	size = (size + 7L) & -8L;
587	list_for_each_entry(chunk, chunk_list, list) {
588		if (chunk->size < size)
589			continue;
590		if (chunk->size > size + sizeof(struct dasd_mchunk)) {
591			char *endaddr = (char *) (chunk + 1) + chunk->size;
592			tmp = (struct dasd_mchunk *) (endaddr - size) - 1;
593			tmp->size = size;
594			chunk->size -= size + sizeof(struct dasd_mchunk);
595			chunk = tmp;
596		} else
597			list_del(&chunk->list);
598		return (void *) (chunk + 1);
599	}
600	return NULL;
601}
602
603static inline void
604dasd_free_chunk(struct list_head *chunk_list, void *mem)
605{
606	struct dasd_mchunk *chunk, *tmp;
607	struct list_head *p, *left;
608
609	chunk = (struct dasd_mchunk *)
610		((char *) mem - sizeof(struct dasd_mchunk));
611	/* Find out the left neighbour in chunk_list. */
612	left = chunk_list;
613	list_for_each(p, chunk_list) {
614		if (list_entry(p, struct dasd_mchunk, list) > chunk)
615			break;
616		left = p;
617	}
618	/* Try to merge with right neighbour = next element from left. */
619	if (left->next != chunk_list) {
620		tmp = list_entry(left->next, struct dasd_mchunk, list);
621		if ((char *) (chunk + 1) + chunk->size == (char *) tmp) {
622			list_del(&tmp->list);
623			chunk->size += tmp->size + sizeof(struct dasd_mchunk);
624		}
625	}
626	/* Try to merge with left neighbour. */
627	if (left != chunk_list) {
628		tmp = list_entry(left, struct dasd_mchunk, list);
629		if ((char *) (tmp + 1) + tmp->size == (char *) chunk) {
630			tmp->size += chunk->size + sizeof(struct dasd_mchunk);
631			return;
632		}
633	}
634	__list_add(&chunk->list, left, left->next);
635}
636
637/*
638 * Check if bsize is in { 512, 1024, 2048, 4096 }
639 */
640static inline int
641dasd_check_blocksize(int bsize)
642{
643	if (bsize < 512 || bsize > 4096 || !is_power_of_2(bsize))
644		return -EMEDIUMTYPE;
645	return 0;
646}
647
648/* externals in dasd.c */
649#define DASD_PROFILE_OFF	 0
650#define DASD_PROFILE_ON 	 1
651#define DASD_PROFILE_GLOBAL_ONLY 2
652
653extern debug_info_t *dasd_debug_area;
654extern struct dasd_profile dasd_global_profile;
655extern unsigned int dasd_global_profile_level;
656extern const struct block_device_operations dasd_device_operations;
657
658extern struct kmem_cache *dasd_page_cache;
659
660struct dasd_ccw_req *
661dasd_kmalloc_request(int , int, int, struct dasd_device *);
662struct dasd_ccw_req *
663dasd_smalloc_request(int , int, int, struct dasd_device *);
664void dasd_kfree_request(struct dasd_ccw_req *, struct dasd_device *);
665void dasd_sfree_request(struct dasd_ccw_req *, struct dasd_device *);
666void dasd_wakeup_cb(struct dasd_ccw_req *, void *);
667
668static inline int
669dasd_kmalloc_set_cda(struct ccw1 *ccw, void *cda, struct dasd_device *device)
670{
671	return set_normalized_cda(ccw, cda);
672}
673
674struct dasd_device *dasd_alloc_device(void);
675void dasd_free_device(struct dasd_device *);
676
677struct dasd_block *dasd_alloc_block(void);
678void dasd_free_block(struct dasd_block *);
679
680enum blk_eh_timer_return dasd_times_out(struct request *req);
681
682void dasd_enable_device(struct dasd_device *);
683void dasd_set_target_state(struct dasd_device *, int);
684void dasd_kick_device(struct dasd_device *);
685void dasd_restore_device(struct dasd_device *);
686void dasd_reload_device(struct dasd_device *);
687
688void dasd_add_request_head(struct dasd_ccw_req *);
689void dasd_add_request_tail(struct dasd_ccw_req *);
690int  dasd_start_IO(struct dasd_ccw_req *);
691int  dasd_term_IO(struct dasd_ccw_req *);
692void dasd_schedule_device_bh(struct dasd_device *);
693void dasd_schedule_block_bh(struct dasd_block *);
694int  dasd_sleep_on(struct dasd_ccw_req *);
695int  dasd_sleep_on_queue(struct list_head *);
696int  dasd_sleep_on_immediatly(struct dasd_ccw_req *);
697int  dasd_sleep_on_interruptible(struct dasd_ccw_req *);
698void dasd_device_set_timer(struct dasd_device *, int);
699void dasd_device_clear_timer(struct dasd_device *);
700void dasd_block_set_timer(struct dasd_block *, int);
701void dasd_block_clear_timer(struct dasd_block *);
702int  dasd_cancel_req(struct dasd_ccw_req *);
703int dasd_flush_device_queue(struct dasd_device *);
704int dasd_generic_probe (struct ccw_device *, struct dasd_discipline *);
705void dasd_generic_remove (struct ccw_device *cdev);
706int dasd_generic_set_online(struct ccw_device *, struct dasd_discipline *);
707int dasd_generic_set_offline (struct ccw_device *cdev);
708int dasd_generic_notify(struct ccw_device *, int);
709int dasd_generic_last_path_gone(struct dasd_device *);
710int dasd_generic_path_operational(struct dasd_device *);
711void dasd_generic_shutdown(struct ccw_device *);
712
713void dasd_generic_handle_state_change(struct dasd_device *);
714int dasd_generic_pm_freeze(struct ccw_device *);
715int dasd_generic_restore_device(struct ccw_device *);
716enum uc_todo dasd_generic_uc_handler(struct ccw_device *, struct irb *);
717void dasd_generic_path_event(struct ccw_device *, int *);
718int dasd_generic_verify_path(struct dasd_device *, __u8);
719
720int dasd_generic_read_dev_chars(struct dasd_device *, int, void *, int);
721char *dasd_get_sense(struct irb *);
722
723void dasd_device_set_stop_bits(struct dasd_device *, int);
724void dasd_device_remove_stop_bits(struct dasd_device *, int);
725
726int dasd_device_is_ro(struct dasd_device *);
727
728void dasd_profile_reset(struct dasd_profile *);
729int dasd_profile_on(struct dasd_profile *);
730void dasd_profile_off(struct dasd_profile *);
731char *dasd_get_user_string(const char __user *, size_t);
732
733/* externals in dasd_devmap.c */
734extern int dasd_max_devindex;
735extern int dasd_probeonly;
736extern int dasd_autodetect;
737extern int dasd_nopav;
738extern int dasd_nofcx;
739
740int dasd_devmap_init(void);
741void dasd_devmap_exit(void);
742
743struct dasd_device *dasd_create_device(struct ccw_device *);
744void dasd_delete_device(struct dasd_device *);
745
746int dasd_get_feature(struct ccw_device *, int);
747int dasd_set_feature(struct ccw_device *, int, int);
748
749int dasd_add_sysfs_files(struct ccw_device *);
750void dasd_remove_sysfs_files(struct ccw_device *);
751
752struct dasd_device *dasd_device_from_cdev(struct ccw_device *);
753struct dasd_device *dasd_device_from_cdev_locked(struct ccw_device *);
754struct dasd_device *dasd_device_from_devindex(int);
755
756void dasd_add_link_to_gendisk(struct gendisk *, struct dasd_device *);
757struct dasd_device *dasd_device_from_gendisk(struct gendisk *);
758
759int dasd_parse(void);
760int dasd_busid_known(const char *);
761
762/* externals in dasd_gendisk.c */
763int  dasd_gendisk_init(void);
764void dasd_gendisk_exit(void);
765int dasd_gendisk_alloc(struct dasd_block *);
766void dasd_gendisk_free(struct dasd_block *);
767int dasd_scan_partitions(struct dasd_block *);
768void dasd_destroy_partitions(struct dasd_block *);
769
770/* externals in dasd_ioctl.c */
771int  dasd_ioctl(struct block_device *, fmode_t, unsigned int, unsigned long);
772
773/* externals in dasd_proc.c */
774int dasd_proc_init(void);
775void dasd_proc_exit(void);
776
777/* externals in dasd_erp.c */
778struct dasd_ccw_req *dasd_default_erp_action(struct dasd_ccw_req *);
779struct dasd_ccw_req *dasd_default_erp_postaction(struct dasd_ccw_req *);
780struct dasd_ccw_req *dasd_alloc_erp_request(char *, int, int,
781					    struct dasd_device *);
782void dasd_free_erp_request(struct dasd_ccw_req *, struct dasd_device *);
783void dasd_log_sense(struct dasd_ccw_req *, struct irb *);
784void dasd_log_sense_dbf(struct dasd_ccw_req *cqr, struct irb *irb);
785
786/* externals in dasd_3990_erp.c */
787struct dasd_ccw_req *dasd_3990_erp_action(struct dasd_ccw_req *);
788void dasd_3990_erp_handle_sim(struct dasd_device *, char *);
789
790/* externals in dasd_eer.c */
791#ifdef CONFIG_DASD_EER
792int dasd_eer_init(void);
793void dasd_eer_exit(void);
794int dasd_eer_enable(struct dasd_device *);
795void dasd_eer_disable(struct dasd_device *);
796void dasd_eer_write(struct dasd_device *, struct dasd_ccw_req *cqr,
797		    unsigned int id);
798void dasd_eer_snss(struct dasd_device *);
799
800static inline int dasd_eer_enabled(struct dasd_device *device)
801{
802	return device->eer_cqr != NULL;
803}
804#else
805#define dasd_eer_init()		(0)
806#define dasd_eer_exit()		do { } while (0)
807#define dasd_eer_enable(d)	(0)
808#define dasd_eer_disable(d)	do { } while (0)
809#define dasd_eer_write(d,c,i)	do { } while (0)
810#define dasd_eer_snss(d)	do { } while (0)
811#define dasd_eer_enabled(d)	(0)
812#endif	/* CONFIG_DASD_ERR */
813
814#endif				/* DASD_H */
815