drivers/s390/block/dasd_int.h

   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         void *cpaddr;                   /* address of ccw or tcw */
 179         unsigned char cpmode;           /* 0 = cmd mode, 1 = itcw */
 180         char status;                    /* status of this request */
 181         short retries;                  /* A retry counter */
 182         unsigned long flags;            /* flags of this request */
 183
 184         /* ... and how */
 185         unsigned long starttime;        /* jiffies time of request start */
 186         unsigned long expires;          /* expiration period in jiffies */
 187         char lpm;                       /* logical path mask */
 188         void *data;                     /* pointer to data area */
 189
 190         /* these are important for recovering erroneous requests          */
 191         int intrc;                      /* internal error, e.g. from start_IO */
 192         struct irb irb;                 /* device status in case of an error */
 193         struct dasd_ccw_req *refers;    /* ERP-chain queueing. */
 194         void *function;                 /* originating ERP action */
 195
 196         /* these are for statistics only */
 197         unsigned long long buildclk;    /* TOD-clock of request generation */
 198         unsigned long long startclk;    /* TOD-clock of request start */
 199         unsigned long long stopclk;     /* TOD-clock of request interrupt */
 200         unsigned long long endclk;      /* TOD-clock of request termination */
 201
 202         /* Callback that is called after reaching final status. */
 203         void (*callback)(struct dasd_ccw_req *, void *data);
 204         void *callback_data;
 205 };
 206
 207 /*
 208  * dasd_ccw_req -> status can be:
 209  */
 210 #define DASD_CQR_FILLED         0x00    /* request is ready to be processed */
 211 #define DASD_CQR_DONE           0x01    /* request is completed successfully */
 212 #define DASD_CQR_NEED_ERP       0x02    /* request needs recovery action */
 213 #define DASD_CQR_IN_ERP         0x03    /* request is in recovery */
 214 #define DASD_CQR_FAILED         0x04    /* request is finally failed */
 215 #define DASD_CQR_TERMINATED     0x05    /* request was stopped by driver */
 216
 217 #define DASD_CQR_QUEUED         0x80    /* request is queued to be processed */
 218 #define DASD_CQR_IN_IO          0x81    /* request is currently in IO */
 219 #define DASD_CQR_ERROR          0x82    /* request is completed with error */
 220 #define DASD_CQR_CLEAR_PENDING  0x83    /* request is clear pending */
 221 #define DASD_CQR_CLEARED        0x84    /* request was cleared */
 222 #define DASD_CQR_SUCCESS        0x85    /* request was successful */
 223
 224 /* default expiration time*/
 225 #define DASD_EXPIRES      300
 226 #define DASD_EXPIRES_MAX  40000000
 227
 228 /* per dasd_ccw_req flags */
 229 #define DASD_CQR_FLAGS_USE_ERP   0      /* use ERP for this request */
 230 #define DASD_CQR_FLAGS_FAILFAST  1      /* FAILFAST */
 231 #define DASD_CQR_VERIFY_PATH     2      /* path verification request */
 232 #define DASD_CQR_ALLOW_SLOCK     3      /* Try this request even when lock was
 233                                          * stolen. Should not be combined with
 234                                          * DASD_CQR_FLAGS_USE_ERP
 235                                          */
 236
 237 /* Signature for error recovery functions. */
 238 typedef struct dasd_ccw_req *(*dasd_erp_fn_t) (struct dasd_ccw_req *);
 239
 240 /*
 241  * Unique identifier for dasd device.
 242  */
 243 #define UA_NOT_CONFIGURED  0x00
 244 #define UA_BASE_DEVICE     0x01
 245 #define UA_BASE_PAV_ALIAS  0x02
 246 #define UA_HYPER_PAV_ALIAS 0x03
 247
 248 struct dasd_uid {
 249         __u8 type;
 250         char vendor[4];
 251         char serial[15];
 252         __u16 ssid;
 253         __u8 real_unit_addr;
 254         __u8 base_unit_addr;
 255         char vduit[33];
 256 };
 257
 258 /*
 259  * the struct dasd_discipline is
 260  * sth like a table of virtual functions, if you think of dasd_eckd
 261  * inheriting dasd...
 262  * no, currently we are not planning to reimplement the driver in C++
 263  */
 264 struct dasd_discipline {
 265         struct module *owner;
 266         char ebcname[8];        /* a name used for tagging and printks */
 267         char name[8];           /* a name used for tagging and printks */
 268         int max_blocks;         /* maximum number of blocks to be chained */
 269
 270         struct list_head list;  /* used for list of disciplines */
 271
 272         /*
 273          * Device recognition functions. check_device is used to verify
 274          * the sense data and the information returned by read device
 275          * characteristics. It returns 0 if the discipline can be used
 276          * for the device in question. uncheck_device is called during
 277          * device shutdown to deregister a device from its discipline.
 278          */
 279         int (*check_device) (struct dasd_device *);
 280         void (*uncheck_device) (struct dasd_device *);
 281
 282         /*
 283          * do_analysis is used in the step from device state "basic" to
 284          * state "accept". It returns 0 if the device can be made ready,
 285          * it returns -EMEDIUMTYPE if the device can't be made ready or
 286          * -EAGAIN if do_analysis started a ccw that needs to complete
 287          * before the analysis may be repeated.
 288          */
 289         int (*do_analysis) (struct dasd_block *);
 290
 291         /*
 292          * This function is called, when new paths become available.
 293          * Disciplins may use this callback to do necessary setup work,
 294          * e.g. verify that new path is compatible with the current
 295          * configuration.
 296          */
 297         int (*verify_path)(struct dasd_device *, __u8);
 298
 299         /*
 300          * Last things to do when a device is set online, and first things
 301          * when it is set offline.
 302          */
 303         int (*ready_to_online) (struct dasd_device *);
 304         int (*online_to_ready) (struct dasd_device *);
 305
 306         /*
 307          * Device operation functions. build_cp creates a ccw chain for
 308          * a block device request, start_io starts the request and
 309          * term_IO cancels it (e.g. in case of a timeout). format_device
 310          * returns a ccw chain to be used to format the device.
 311          * handle_terminated_request allows to examine a cqr and prepare
 312          * it for retry.
 313          */
 314         struct dasd_ccw_req *(*build_cp) (struct dasd_device *,
 315                                           struct dasd_block *,
 316                                           struct request *);
 317         int (*start_IO) (struct dasd_ccw_req *);
 318         int (*term_IO) (struct dasd_ccw_req *);
 319         void (*handle_terminated_request) (struct dasd_ccw_req *);
 320         struct dasd_ccw_req *(*format_device) (struct dasd_device *,
 321                                                struct format_data_t *);
 322         int (*free_cp) (struct dasd_ccw_req *, struct request *);
 323
 324         /*
 325          * Error recovery functions. examine_error() returns a value that
 326          * indicates what to do for an error condition. If examine_error()
 327          * returns 'dasd_era_recover' erp_action() is called to create a
 328          * special error recovery ccw. erp_postaction() is called after
 329          * an error recovery ccw has finished its execution. dump_sense
 330          * is called for every error condition to print the sense data
 331          * to the console.
 332          */
 333         dasd_erp_fn_t(*erp_action) (struct dasd_ccw_req *);
 334         dasd_erp_fn_t(*erp_postaction) (struct dasd_ccw_req *);
 335         void (*dump_sense) (struct dasd_device *, struct dasd_ccw_req *,
 336                             struct irb *);
 337         void (*dump_sense_dbf) (struct dasd_device *, struct irb *, char *);
 338         void (*check_for_device_change) (struct dasd_device *,
 339                                          struct dasd_ccw_req *,
 340                                          struct irb *);
 341
 342         /* i/o control functions. */
 343         int (*fill_geometry) (struct dasd_block *, struct hd_geometry *);
 344         int (*fill_info) (struct dasd_device *, struct dasd_information2_t *);
 345         int (*ioctl) (struct dasd_block *, unsigned int, void __user *);
 346
 347         /* suspend/resume functions */
 348         int (*freeze) (struct dasd_device *);
 349         int (*restore) (struct dasd_device *);
 350
 351         /* reload device after state change */
 352         int (*reload) (struct dasd_device *);
 353
 354         int (*get_uid) (struct dasd_device *, struct dasd_uid *);
 355         void (*kick_validate) (struct dasd_device *);
 356 };
 357
 358 extern struct dasd_discipline *dasd_diag_discipline_pointer;
 359
 360 /*
 361  * Notification numbers for extended error reporting notifications:
 362  * The DASD_EER_DISABLE notification is sent before a dasd_device (and it's
 363  * eer pointer) is freed. The error reporting module needs to do all necessary
 364  * cleanup steps.
 365  * The DASD_EER_TRIGGER notification sends the actual error reports (triggers).
 366  */
 367 #define DASD_EER_DISABLE 0
 368 #define DASD_EER_TRIGGER 1
 369
 370 /* Trigger IDs for extended error reporting DASD_EER_TRIGGER notification */
 371 #define DASD_EER_FATALERROR  1
 372 #define DASD_EER_NOPATH      2
 373 #define DASD_EER_STATECHANGE 3
 374 #define DASD_EER_PPRCSUSPEND 4
 375
 376 struct dasd_path {
 377         __u8 opm;
 378         __u8 tbvpm;
 379         __u8 ppm;
 380         __u8 npm;
 381 };
 382
 383 struct dasd_profile_info {
 384         /* legacy part of profile data, as in dasd_profile_info_t */
 385         unsigned int dasd_io_reqs;       /* number of requests processed */
 386         unsigned int dasd_io_sects;      /* number of sectors processed */
 387         unsigned int dasd_io_secs[32];   /* histogram of request's sizes */
 388         unsigned int dasd_io_times[32];  /* histogram of requests's times */
 389         unsigned int dasd_io_timps[32];  /* h. of requests's times per sector */
 390         unsigned int dasd_io_time1[32];  /* hist. of time from build to start */
 391         unsigned int dasd_io_time2[32];  /* hist. of time from start to irq */
 392         unsigned int dasd_io_time2ps[32]; /* hist. of time from start to irq */
 393         unsigned int dasd_io_time3[32];  /* hist. of time from irq to end */
 394         unsigned int dasd_io_nr_req[32]; /* hist. of # of requests in chanq */
 395
 396         /* new data */
 397         struct timespec starttod;          /* time of start or last reset */
 398         unsigned int dasd_io_alias;        /* requests using an alias */
 399         unsigned int dasd_io_tpm;          /* requests using transport mode */
 400         unsigned int dasd_read_reqs;       /* total number of read  requests */
 401         unsigned int dasd_read_sects;      /* total number read sectors */
 402         unsigned int dasd_read_alias;      /* read request using an alias */
 403         unsigned int dasd_read_tpm;        /* read requests in transport mode */
 404         unsigned int dasd_read_secs[32];   /* histogram of request's sizes */
 405         unsigned int dasd_read_times[32];  /* histogram of requests's times */
 406         unsigned int dasd_read_time1[32];  /* hist. time from build to start */
 407         unsigned int dasd_read_time2[32];  /* hist. of time from start to irq */
 408         unsigned int dasd_read_time3[32];  /* hist. of time from irq to end */
 409         unsigned int dasd_read_nr_req[32]; /* hist. of # of requests in chanq */
 410 };
 411
 412 struct dasd_profile {
 413         struct dentry *dentry;
 414         struct dasd_profile_info *data;
 415         spinlock_t lock;
 416 };
 417
 418 struct dasd_device {
 419         /* Block device stuff. */
 420         struct dasd_block *block;
 421
 422         unsigned int devindex;
 423         unsigned long flags;       /* per device flags */
 424         unsigned short features;   /* copy of devmap-features (read-only!) */
 425
 426         /* extended error reporting stuff (eer) */
 427         struct dasd_ccw_req *eer_cqr;
 428
 429         /* Device discipline stuff. */
 430         struct dasd_discipline *discipline;
 431         struct dasd_discipline *base_discipline;
 432         char *private;
 433         struct dasd_path path_data;
 434
 435         /* Device state and target state. */
 436         int state, target;
 437         struct mutex state_mutex;
 438         int stopped;            /* device (ccw_device_start) was stopped */
 439
 440         /* reference count. */
 441         atomic_t ref_count;
 442
 443         /* ccw queue and memory for static ccw/erp buffers. */
 444         struct list_head ccw_queue;
 445         spinlock_t mem_lock;
 446         void *ccw_mem;
 447         void *erp_mem;
 448         struct list_head ccw_chunks;
 449         struct list_head erp_chunks;
 450
 451         atomic_t tasklet_scheduled;
 452         struct tasklet_struct tasklet;
 453         struct work_struct kick_work;
 454         struct work_struct restore_device;
 455         struct work_struct reload_device;
 456         struct work_struct kick_validate;
 457         struct timer_list timer;
 458
 459         debug_info_t *debug_area;
 460
 461         struct ccw_device *cdev;
 462
 463         /* hook for alias management */
 464         struct list_head alias_list;
 465
 466         /* default expiration time in s */
 467         unsigned long default_expires;
 468
 469         struct dentry *debugfs_dentry;
 470         struct dasd_profile profile;
 471 };
 472
 473 struct dasd_block {
 474         /* Block device stuff. */
 475         struct gendisk *gdp;
 476         struct request_queue *request_queue;
 477         spinlock_t request_queue_lock;
 478         struct block_device *bdev;
 479         atomic_t open_count;
 480
 481         unsigned long long blocks; /* size of volume in blocks */
 482         unsigned int bp_block;     /* bytes per block */
 483         unsigned int s2b_shift;    /* log2 (bp_block/512) */
 484
 485         struct dasd_device *base;
 486         struct list_head ccw_queue;
 487         spinlock_t queue_lock;
 488
 489         atomic_t tasklet_scheduled;
 490         struct tasklet_struct tasklet;
 491         struct timer_list timer;
 492
 493         struct dentry *debugfs_dentry;
 494         struct dasd_profile profile;
 495 };
 496
 497
 498
 499 /* reasons why device (ccw_device_start) was stopped */
 500 #define DASD_STOPPED_NOT_ACC 1         /* not accessible */
 501 #define DASD_STOPPED_QUIESCE 2         /* Quiesced */
 502 #define DASD_STOPPED_PENDING 4         /* long busy */
 503 #define DASD_STOPPED_DC_WAIT 8         /* disconnected, wait */
 504 #define DASD_STOPPED_SU      16        /* summary unit check handling */
 505 #define DASD_STOPPED_PM      32        /* pm state transition */
 506 #define DASD_UNRESUMED_PM    64        /* pm resume failed state */
 507
 508 /* per device flags */
 509 #define DASD_FLAG_OFFLINE       3       /* device is in offline processing */
 510 #define DASD_FLAG_EER_SNSS      4       /* A SNSS is required */
 511 #define DASD_FLAG_EER_IN_USE    5       /* A SNSS request is running */
 512 #define DASD_FLAG_DEVICE_RO     6       /* The device itself is read-only. Don't
 513                                          * confuse this with the user specified
 514                                          * read-only feature.
 515                                          */
 516 #define DASD_FLAG_IS_RESERVED   7       /* The device is reserved */
 517 #define DASD_FLAG_LOCK_STOLEN   8       /* The device lock was stolen */
 518 #define DASD_FLAG_SUSPENDED     9       /* The device was suspended */
 519
 520
 521 void dasd_put_device_wake(struct dasd_device *);
 522
 523 /*
 524  * Reference count inliners
 525  */
 526 static inline void
 527 dasd_get_device(struct dasd_device *device)
 528 {
 529         atomic_inc(&device->ref_count);
 530 }
 531
 532 static inline void
 533 dasd_put_device(struct dasd_device *device)
 534 {
 535         if (atomic_dec_return(&device->ref_count) == 0)
 536                 dasd_put_device_wake(device);
 537 }
 538
 539 /*
 540  * The static memory in ccw_mem and erp_mem is managed by a sorted
 541  * list of free memory chunks.
 542  */
 543 struct dasd_mchunk
 544 {
 545         struct list_head list;
 546         unsigned long size;
 547 } __attribute__ ((aligned(8)));
 548
 549 static inline void
 550 dasd_init_chunklist(struct list_head *chunk_list, void *mem,
 551                     unsigned long size)
 552 {
 553         struct dasd_mchunk *chunk;
 554
 555         INIT_LIST_HEAD(chunk_list);
 556         chunk = (struct dasd_mchunk *) mem;
 557         chunk->size = size - sizeof(struct dasd_mchunk);
 558         list_add(&chunk->list, chunk_list);
 559 }
 560
 561 static inline void *
 562 dasd_alloc_chunk(struct list_head *chunk_list, unsigned long size)
 563 {
 564         struct dasd_mchunk *chunk, *tmp;
 565
 566         size = (size + 7L) & -8L;
 567         list_for_each_entry(chunk, chunk_list, list) {
 568                 if (chunk->size < size)
 569                         continue;
 570                 if (chunk->size > size + sizeof(struct dasd_mchunk)) {
 571                         char *endaddr = (char *) (chunk + 1) + chunk->size;
 572                         tmp = (struct dasd_mchunk *) (endaddr - size) - 1;
 573                         tmp->size = size;
 574                         chunk->size -= size + sizeof(struct dasd_mchunk);
 575                         chunk = tmp;
 576                 } else
 577                         list_del(&chunk->list);
 578                 return (void *) (chunk + 1);
 579         }
 580         return NULL;
 581 }
 582
 583 static inline void
 584 dasd_free_chunk(struct list_head *chunk_list, void *mem)
 585 {
 586         struct dasd_mchunk *chunk, *tmp;
 587         struct list_head *p, *left;
 588
 589         chunk = (struct dasd_mchunk *)
 590                 ((char *) mem - sizeof(struct dasd_mchunk));
 591         /* Find out the left neighbour in chunk_list. */
 592         left = chunk_list;
 593         list_for_each(p, chunk_list) {
 594                 if (list_entry(p, struct dasd_mchunk, list) > chunk)
 595                         break;
 596                 left = p;
 597         }
 598         /* Try to merge with right neighbour = next element from left. */
 599         if (left->next != chunk_list) {
 600                 tmp = list_entry(left->next, struct dasd_mchunk, list);
 601                 if ((char *) (chunk + 1) + chunk->size == (char *) tmp) {
 602                         list_del(&tmp->list);
 603                         chunk->size += tmp->size + sizeof(struct dasd_mchunk);
 604                 }
 605         }
 606         /* Try to merge with left neighbour. */
 607         if (left != chunk_list) {
 608                 tmp = list_entry(left, struct dasd_mchunk, list);
 609                 if ((char *) (tmp + 1) + tmp->size == (char *) chunk) {
 610                         tmp->size += chunk->size + sizeof(struct dasd_mchunk);
 611                         return;
 612                 }
 613         }
 614         __list_add(&chunk->list, left, left->next);
 615 }
 616
 617 /*
 618  * Check if bsize is in { 512, 1024, 2048, 4096 }
 619  */
 620 static inline int
 621 dasd_check_blocksize(int bsize)
 622 {
 623         if (bsize < 512 || bsize > 4096 || !is_power_of_2(bsize))
 624                 return -EMEDIUMTYPE;
 625         return 0;
 626 }
 627
 628 /* externals in dasd.c */
 629 #define DASD_PROFILE_OFF         0
 630 #define DASD_PROFILE_ON          1
 631 #define DASD_PROFILE_GLOBAL_ONLY 2
 632
 633 extern debug_info_t *dasd_debug_area;
 634 extern struct dasd_profile_info dasd_global_profile_data;
 635 extern unsigned int dasd_global_profile_level;
 636 extern const struct block_device_operations dasd_device_operations;
 637
 638 extern struct kmem_cache *dasd_page_cache;
 639
 640 struct dasd_ccw_req *
 641 dasd_kmalloc_request(int , int, int, struct dasd_device *);
 642 struct dasd_ccw_req *
 643 dasd_smalloc_request(int , int, int, struct dasd_device *);
 644 void dasd_kfree_request(struct dasd_ccw_req *, struct dasd_device *);
 645 void dasd_sfree_request(struct dasd_ccw_req *, struct dasd_device *);
 646 void dasd_wakeup_cb(struct dasd_ccw_req *, void *);
 647
 648 static inline int
 649 dasd_kmalloc_set_cda(struct ccw1 *ccw, void *cda, struct dasd_device *device)
 650 {
 651         return set_normalized_cda(ccw, cda);
 652 }
 653
 654 struct dasd_device *dasd_alloc_device(void);
 655 void dasd_free_device(struct dasd_device *);
 656
 657 struct dasd_block *dasd_alloc_block(void);
 658 void dasd_free_block(struct dasd_block *);
 659
 660 void dasd_enable_device(struct dasd_device *);
 661 void dasd_set_target_state(struct dasd_device *, int);
 662 void dasd_kick_device(struct dasd_device *);
 663 void dasd_restore_device(struct dasd_device *);
 664 void dasd_reload_device(struct dasd_device *);
 665
 666 void dasd_add_request_head(struct dasd_ccw_req *);
 667 void dasd_add_request_tail(struct dasd_ccw_req *);
 668 int  dasd_start_IO(struct dasd_ccw_req *);
 669 int  dasd_term_IO(struct dasd_ccw_req *);
 670 void dasd_schedule_device_bh(struct dasd_device *);
 671 void dasd_schedule_block_bh(struct dasd_block *);
 672 int  dasd_sleep_on(struct dasd_ccw_req *);
 673 int  dasd_sleep_on_immediatly(struct dasd_ccw_req *);
 674 int  dasd_sleep_on_interruptible(struct dasd_ccw_req *);
 675 void dasd_device_set_timer(struct dasd_device *, int);
 676 void dasd_device_clear_timer(struct dasd_device *);
 677 void dasd_block_set_timer(struct dasd_block *, int);
 678 void dasd_block_clear_timer(struct dasd_block *);
 679 int  dasd_cancel_req(struct dasd_ccw_req *);
 680 int dasd_flush_device_queue(struct dasd_device *);
 681 int dasd_generic_probe (struct ccw_device *, struct dasd_discipline *);
 682 void dasd_generic_remove (struct ccw_device *cdev);
 683 int dasd_generic_set_online(struct ccw_device *, struct dasd_discipline *);
 684 int dasd_generic_set_offline (struct ccw_device *cdev);
 685 int dasd_generic_notify(struct ccw_device *, int);
 686 int dasd_generic_last_path_gone(struct dasd_device *);
 687 int dasd_generic_path_operational(struct dasd_device *);
 688 void dasd_generic_shutdown(struct ccw_device *);
 689
 690 void dasd_generic_handle_state_change(struct dasd_device *);
 691 int dasd_generic_pm_freeze(struct ccw_device *);
 692 int dasd_generic_restore_device(struct ccw_device *);
 693 enum uc_todo dasd_generic_uc_handler(struct ccw_device *, struct irb *);
 694 void dasd_generic_path_event(struct ccw_device *, int *);
 695 int dasd_generic_verify_path(struct dasd_device *, __u8);
 696
 697 int dasd_generic_read_dev_chars(struct dasd_device *, int, void *, int);
 698 char *dasd_get_sense(struct irb *);
 699
 700 void dasd_device_set_stop_bits(struct dasd_device *, int);
 701 void dasd_device_remove_stop_bits(struct dasd_device *, int);
 702
 703 int dasd_device_is_ro(struct dasd_device *);
 704
 705 void dasd_profile_reset(struct dasd_profile *);
 706 int dasd_profile_on(struct dasd_profile *);
 707 void dasd_profile_off(struct dasd_profile *);
 708 void dasd_global_profile_reset(void);
 709 char *dasd_get_user_string(const char __user *, size_t);
 710
 711 /* externals in dasd_devmap.c */
 712 extern int dasd_max_devindex;
 713 extern int dasd_probeonly;
 714 extern int dasd_autodetect;
 715 extern int dasd_nopav;
 716 extern int dasd_nofcx;
 717
 718 int dasd_devmap_init(void);
 719 void dasd_devmap_exit(void);
 720
 721 struct dasd_device *dasd_create_device(struct ccw_device *);
 722 void dasd_delete_device(struct dasd_device *);
 723
 724 int dasd_get_feature(struct ccw_device *, int);
 725 int dasd_set_feature(struct ccw_device *, int, int);
 726
 727 int dasd_add_sysfs_files(struct ccw_device *);
 728 void dasd_remove_sysfs_files(struct ccw_device *);
 729
 730 struct dasd_device *dasd_device_from_cdev(struct ccw_device *);
 731 struct dasd_device *dasd_device_from_cdev_locked(struct ccw_device *);
 732 struct dasd_device *dasd_device_from_devindex(int);
 733
 734 void dasd_add_link_to_gendisk(struct gendisk *, struct dasd_device *);
 735 struct dasd_device *dasd_device_from_gendisk(struct gendisk *);
 736
 737 int dasd_parse(void);
 738 int dasd_busid_known(const char *);
 739
 740 /* externals in dasd_gendisk.c */
 741 int  dasd_gendisk_init(void);
 742 void dasd_gendisk_exit(void);
 743 int dasd_gendisk_alloc(struct dasd_block *);
 744 void dasd_gendisk_free(struct dasd_block *);
 745 int dasd_scan_partitions(struct dasd_block *);
 746 void dasd_destroy_partitions(struct dasd_block *);
 747
 748 /* externals in dasd_ioctl.c */
 749 int  dasd_ioctl(struct block_device *, fmode_t, unsigned int, unsigned long);
 750
 751 /* externals in dasd_proc.c */
 752 int dasd_proc_init(void);
 753 void dasd_proc_exit(void);
 754
 755 /* externals in dasd_erp.c */
 756 struct dasd_ccw_req *dasd_default_erp_action(struct dasd_ccw_req *);
 757 struct dasd_ccw_req *dasd_default_erp_postaction(struct dasd_ccw_req *);
 758 struct dasd_ccw_req *dasd_alloc_erp_request(char *, int, int,
 759                                             struct dasd_device *);
 760 void dasd_free_erp_request(struct dasd_ccw_req *, struct dasd_device *);
 761 void dasd_log_sense(struct dasd_ccw_req *, struct irb *);
 762 void dasd_log_sense_dbf(struct dasd_ccw_req *cqr, struct irb *irb);
 763
 764 /* externals in dasd_3990_erp.c */
 765 struct dasd_ccw_req *dasd_3990_erp_action(struct dasd_ccw_req *);
 766 void dasd_3990_erp_handle_sim(struct dasd_device *, char *);
 767
 768 /* externals in dasd_eer.c */
 769 #ifdef CONFIG_DASD_EER
 770 int dasd_eer_init(void);
 771 void dasd_eer_exit(void);
 772 int dasd_eer_enable(struct dasd_device *);
 773 void dasd_eer_disable(struct dasd_device *);
 774 void dasd_eer_write(struct dasd_device *, struct dasd_ccw_req *cqr,
 775                     unsigned int id);
 776 void dasd_eer_snss(struct dasd_device *);
 777
 778 static inline int dasd_eer_enabled(struct dasd_device *device)
 779 {
 780         return device->eer_cqr != NULL;
 781 }
 782 #else
 783 #define dasd_eer_init()         (0)
 784 #define dasd_eer_exit()         do { } while (0)
 785 #define dasd_eer_enable(d)      (0)
 786 #define dasd_eer_disable(d)     do { } while (0)
 787 #define dasd_eer_write(d,c,i)   do { } while (0)
 788 #define dasd_eer_snss(d)        do { } while (0)
 789 #define dasd_eer_enabled(d)     (0)
 790 #endif  /* CONFIG_DASD_ERR */
 791
 792 #endif                          /* DASD_H */