LXR linux/drivers/s390/block/dasd

   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        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#define DASD_RETRIES      256
 228#define DASD_RETRIES_MAX  32768
 229
 230/* per dasd_ccw_req flags */
 231#define DASD_CQR_FLAGS_USE_ERP   0      /* use ERP for this request */
 232#define DASD_CQR_FLAGS_FAILFAST  1      /* FAILFAST */
 233#define DASD_CQR_VERIFY_PATH     2      /* path verification request */
 234#define DASD_CQR_ALLOW_SLOCK     3      /* Try this request even when lock was
 235                                         * stolen. Should not be combined with
 236                                         * DASD_CQR_FLAGS_USE_ERP
 237                                         */
 238
 239/* Signature for error recovery functions. */
 240typedef struct dasd_ccw_req *(*dasd_erp_fn_t) (struct dasd_ccw_req *);
 241
 242/*
 243 * Unique identifier for dasd device.
 244 */
 245#define UA_NOT_CONFIGURED  0x00
 246#define UA_BASE_DEVICE     0x01
 247#define UA_BASE_PAV_ALIAS  0x02
 248#define UA_HYPER_PAV_ALIAS 0x03
 249
 250struct dasd_uid {
 251        __u8 type;
 252        char vendor[4];
 253        char serial[15];
 254        __u16 ssid;
 255        __u8 real_unit_addr;
 256        __u8 base_unit_addr;
 257        char vduit[33];
 258};
 259
 260/*
 261 * the struct dasd_discipline is
 262 * sth like a table of virtual functions, if you think of dasd_eckd
 263 * inheriting dasd...
 264 * no, currently we are not planning to reimplement the driver in C++
 265 */
 266struct dasd_discipline {
 267        struct module *owner;
 268        char ebcname[8];        /* a name used for tagging and printks */
 269        char name[8];           /* a name used for tagging and printks */
 270        int max_blocks;         /* maximum number of blocks to be chained */
 271
 272        struct list_head list;  /* used for list of disciplines */
 273
 274        /*
 275         * Device recognition functions. check_device is used to verify
 276         * the sense data and the information returned by read device
 277         * characteristics. It returns 0 if the discipline can be used
 278         * for the device in question. uncheck_device is called during
 279         * device shutdown to deregister a device from its discipline.
 280         */
 281        int (*check_device) (struct dasd_device *);
 282        void (*uncheck_device) (struct dasd_device *);
 283
 284        /*
 285         * do_analysis is used in the step from device state "basic" to
 286         * state "accept". It returns 0 if the device can be made ready,
 287         * it returns -EMEDIUMTYPE if the device can't be made ready or
 288         * -EAGAIN if do_analysis started a ccw that needs to complete
 289         * before the analysis may be repeated.
 290         */
 291        int (*do_analysis) (struct dasd_block *);
 292
 293        /*
 294         * This function is called, when new paths become available.
 295         * Disciplins may use this callback to do necessary setup work,
 296         * e.g. verify that new path is compatible with the current
 297         * configuration.
 298         */
 299        int (*verify_path)(struct dasd_device *, __u8);
 300
 301        /*
 302         * Last things to do when a device is set online, and first things
 303         * when it is set offline.
 304         */
 305        int (*basic_to_ready) (struct dasd_device *);
 306        int (*online_to_ready) (struct dasd_device *);
 307        int (*ready_to_basic)  (struct dasd_device *);
 308
 309        /* (struct dasd_device *);
 310         * Device operation functions. build_cp creates a ccw chain for
 311         * a block device request, start_io starts the request and
 312         * term_IO cancels it (e.g. in case of a timeout). format_device
 313         * returns a ccw chain to be used to format the device.
 314         * handle_terminated_request allows to examine a cqr and prepare
 315         * it for retry.
 316         */
 317        struct dasd_ccw_req *(*build_cp) (struct dasd_device *,
 318                                          struct dasd_block *,
 319                                          struct request *);
 320        int (*start_IO) (struct dasd_ccw_req *);
 321        int (*term_IO) (struct dasd_ccw_req *);
 322        void (*handle_terminated_request) (struct dasd_ccw_req *);
 323        int (*format_device) (struct dasd_device *,
 324                              struct format_data_t *);
 325        int (*free_cp) (struct dasd_ccw_req *, struct request *);
 326
 327        /*
 328         * Error recovery functions. examine_error() returns a value that
 329         * indicates what to do for an error condition. If examine_error()
 330         * returns 'dasd_era_recover' erp_action() is called to create a
 331         * special error recovery ccw. erp_postaction() is called after
 332         * an error recovery ccw has finished its execution. dump_sense
 333         * is called for every error condition to print the sense data
 334         * to the console.
 335         */
 336        dasd_erp_fn_t(*erp_action) (struct dasd_ccw_req *);
 337        dasd_erp_fn_t(*erp_postaction) (struct dasd_ccw_req *);
 338        void (*dump_sense) (struct dasd_device *, struct dasd_ccw_req *,
 339                            struct irb *);
 340        void (*dump_sense_dbf) (struct dasd_device *, struct irb *, char *);
 341        void (*check_for_device_change) (struct dasd_device *,
 342                                         struct dasd_ccw_req *,
 343                                         struct irb *);
 344
 345        /* i/o control functions. */
 346        int (*fill_geometry) (struct dasd_block *, struct hd_geometry *);
 347        int (*fill_info) (struct dasd_device *, struct dasd_information2_t *);
 348        int (*ioctl) (struct dasd_block *, unsigned int, void __user *);
 349
 350        /* suspend/resume functions */
 351        int (*freeze) (struct dasd_device *);
 352        int (*restore) (struct dasd_device *);
 353
 354        /* reload device after state change */
 355        int (*reload) (struct dasd_device *);
 356
 357        int (*get_uid) (struct dasd_device *, struct dasd_uid *);
 358        void (*kick_validate) (struct dasd_device *);
 359};
 360
 361extern struct dasd_discipline *dasd_diag_discipline_pointer;
 362
 363/*
 364 * Notification numbers for extended error reporting notifications:
 365 * The DASD_EER_DISABLE notification is sent before a dasd_device (and it's
 366 * eer pointer) is freed. The error reporting module needs to do all necessary
 367 * cleanup steps.
 368 * The DASD_EER_TRIGGER notification sends the actual error reports (triggers).
 369 */
 370#define DASD_EER_DISABLE 0
 371#define DASD_EER_TRIGGER 1
 372
 373/* Trigger IDs for extended error reporting DASD_EER_TRIGGER notification */
 374#define DASD_EER_FATALERROR  1
 375#define DASD_EER_NOPATH      2
 376#define DASD_EER_STATECHANGE 3
 377#define DASD_EER_PPRCSUSPEND 4
 378
 379struct dasd_path {
 380        __u8 opm;
 381        __u8 tbvpm;
 382        __u8 ppm;
 383        __u8 npm;
 384};
 385
 386struct dasd_profile_info {
 387        /* legacy part of profile data, as in dasd_profile_info_t */
 388        unsigned int dasd_io_reqs;       /* number of requests processed */
 389        unsigned int dasd_io_sects;      /* number of sectors processed */
 390        unsigned int dasd_io_secs[32];   /* histogram of request's sizes */
 391        unsigned int dasd_io_times[32];  /* histogram of requests's times */
 392        unsigned int dasd_io_timps[32];  /* h. of requests's times per sector */
 393        unsigned int dasd_io_time1[32];  /* hist. of time from build to start */
 394        unsigned int dasd_io_time2[32];  /* hist. of time from start to irq */
 395        unsigned int dasd_io_time2ps[32]; /* hist. of time from start to irq */
 396        unsigned int dasd_io_time3[32];  /* hist. of time from irq to end */
 397        unsigned int dasd_io_nr_req[32]; /* hist. of # of requests in chanq */
 398
 399        /* new data */
 400        struct timespec starttod;          /* time of start or last reset */
 401        unsigned int dasd_io_alias;        /* requests using an alias */
 402        unsigned int dasd_io_tpm;          /* requests using transport mode */
 403        unsigned int dasd_read_reqs;       /* total number of read  requests */
 404        unsigned int dasd_read_sects;      /* total number read sectors */
 405        unsigned int dasd_read_alias;      /* read request using an alias */
 406        unsigned int dasd_read_tpm;        /* read requests in transport mode */
 407        unsigned int dasd_read_secs[32];   /* histogram of request's sizes */
 408        unsigned int dasd_read_times[32];  /* histogram of requests's times */
 409        unsigned int dasd_read_time1[32];  /* hist. time from build to start */
 410        unsigned int dasd_read_time2[32];  /* hist. of time from start to irq */
 411        unsigned int dasd_read_time3[32];  /* hist. of time from irq to end */
 412        unsigned int dasd_read_nr_req[32]; /* hist. of # of requests in chanq */
 413};
 414
 415struct dasd_profile {
 416        struct dentry *dentry;
 417        struct dasd_profile_info *data;
 418        spinlock_t lock;
 419};
 420
 421struct dasd_device {
 422        /* Block device stuff. */
 423        struct dasd_block *block;
 424
 425        unsigned int devindex;
 426        unsigned long flags;       /* per device flags */
 427        unsigned short features;   /* copy of devmap-features (read-only!) */
 428
 429        /* extended error reporting stuff (eer) */
 430        struct dasd_ccw_req *eer_cqr;
 431
 432        /* Device discipline stuff. */
 433        struct dasd_discipline *discipline;
 434        struct dasd_discipline *base_discipline;
 435        char *private;
 436        struct dasd_path path_data;
 437
 438        /* Device state and target state. */
 439        int state, target;
 440        struct mutex state_mutex;
 441        int stopped;            /* device (ccw_device_start) was stopped */
 442
 443        /* reference count. */
 444        atomic_t ref_count;
 445
 446        /* ccw queue and memory for static ccw/erp buffers. */
 447        struct list_head ccw_queue;
 448        spinlock_t mem_lock;
 449        void *ccw_mem;
 450        void *erp_mem;
 451        struct list_head ccw_chunks;
 452        struct list_head erp_chunks;
 453
 454        atomic_t tasklet_scheduled;
 455        struct tasklet_struct tasklet;
 456        struct work_struct kick_work;
 457        struct work_struct restore_device;
 458        struct work_struct reload_device;
 459        struct work_struct kick_validate;
 460        struct timer_list timer;
 461
 462        debug_info_t *debug_area;
 463
 464        struct ccw_device *cdev;
 465
 466        /* hook for alias management */
 467        struct list_head alias_list;
 468
 469        /* default expiration time in s */
 470        unsigned long default_expires;
 471        unsigned long default_retries;
 472
 473        unsigned long blk_timeout;
 474
 475        struct dentry *debugfs_dentry;
 476        struct dasd_profile profile;
 477};
 478
 479struct dasd_block {
 480        /* Block device stuff. */
 481        struct gendisk *gdp;
 482        struct request_queue *request_queue;
 483        spinlock_t request_queue_lock;
 484        struct block_device *bdev;
 485        atomic_t open_count;
 486
 487        unsigned long long blocks; /* size of volume in blocks */
 488        unsigned int bp_block;     /* bytes per block */
 489        unsigned int s2b_shift;    /* log2 (bp_block/512) */
 490
 491        struct dasd_device *base;
 492        struct list_head ccw_queue;
 493        spinlock_t queue_lock;
 494
 495        atomic_t tasklet_scheduled;
 496        struct tasklet_struct tasklet;
 497        struct timer_list timer;
 498
 499        struct dentry *debugfs_dentry;
 500        struct dasd_profile profile;
 501};
 502
 503
 504
 505/* reasons why device (ccw_device_start) was stopped */
 506#define DASD_STOPPED_NOT_ACC 1         /* not accessible */
 507#define DASD_STOPPED_QUIESCE 2         /* Quiesced */
 508#define DASD_STOPPED_PENDING 4         /* long busy */
 509#define DASD_STOPPED_DC_WAIT 8         /* disconnected, wait */
 510#define DASD_STOPPED_SU      16        /* summary unit check handling */
 511#define DASD_STOPPED_PM      32        /* pm state transition */
 512#define DASD_UNRESUMED_PM    64        /* pm resume failed state */
 513
 514/* per device flags */
 515#define DASD_FLAG_OFFLINE       3       /* device is in offline processing */
 516#define DASD_FLAG_EER_SNSS      4       /* A SNSS is required */
 517#define DASD_FLAG_EER_IN_USE    5       /* A SNSS request is running */
 518#define DASD_FLAG_DEVICE_RO     6       /* The device itself is read-only. Don't
 519                                         * confuse this with the user specified
 520                                         * read-only feature.
 521                                         */
 522#define DASD_FLAG_IS_RESERVED   7       /* The device is reserved */
 523#define DASD_FLAG_LOCK_STOLEN   8       /* The device lock was stolen */
 524#define DASD_FLAG_SUSPENDED     9       /* The device was suspended */
 525#define DASD_FLAG_SAFE_OFFLINE  10      /* safe offline processing requested*/
 526#define DASD_FLAG_SAFE_OFFLINE_RUNNING  11      /* safe offline running */
 527#define DASD_FLAG_ABORTALL      12      /* Abort all noretry requests */
 528
 529#define DASD_SLEEPON_START_TAG  ((void *) 1)
 530#define DASD_SLEEPON_END_TAG    ((void *) 2)
 531
 532void dasd_put_device_wake(struct dasd_device *);
 533
 534/*
 535 * Reference count inliners
 536 */
 537static inline void
 538dasd_get_device(struct dasd_device *device)
 539{
 540        atomic_inc(&device->ref_count);
 541}
 542
 543static inline void
 544dasd_put_device(struct dasd_device *device)
 545{
 546        if (atomic_dec_return(&device->ref_count) == 0)
 547                dasd_put_device_wake(device);
 548}
 549
 550/*
 551 * The static memory in ccw_mem and erp_mem is managed by a sorted
 552 * list of free memory chunks.
 553 */
 554struct dasd_mchunk
 555{
 556        struct list_head list;
 557        unsigned long size;
 558} __attribute__ ((aligned(8)));
 559
 560static inline void
 561dasd_init_chunklist(struct list_head *chunk_list, void *mem,
 562                    unsigned long size)
 563{
 564        struct dasd_mchunk *chunk;
 565
 566        INIT_LIST_HEAD(chunk_list);
 567        chunk = (struct dasd_mchunk *) mem;
 568        chunk->size = size - sizeof(struct dasd_mchunk);
 569        list_add(&chunk->list, chunk_list);
 570}
 571
 572static inline void *
 573dasd_alloc_chunk(struct list_head *chunk_list, unsigned long size)
 574{
 575        struct dasd_mchunk *chunk, *tmp;
 576
 577        size = (size + 7L) & -8L;
 578        list_for_each_entry(chunk, chunk_list, list) {
 579                if (chunk->size < size)
 580                        continue;
 581                if (chunk->size > size + sizeof(struct dasd_mchunk)) {
 582                        char *endaddr = (char *) (chunk + 1) + chunk->size;
 583                        tmp = (struct dasd_mchunk *) (endaddr - size) - 1;
 584                        tmp->size = size;
 585                        chunk->size -= size + sizeof(struct dasd_mchunk);
 586                        chunk = tmp;
 587                } else
 588                        list_del(&chunk->list);
 589                return (void *) (chunk + 1);
 590        }
 591        return NULL;
 592}
 593
 594static inline void
 595dasd_free_chunk(struct list_head *chunk_list, void *mem)
 596{
 597        struct dasd_mchunk *chunk, *tmp;
 598        struct list_head *p, *left;
 599
 600        chunk = (struct dasd_mchunk *)
 601                ((char *) mem - sizeof(struct dasd_mchunk));
 602        /* Find out the left neighbour in chunk_list. */
 603        left = chunk_list;
 604        list_for_each(p, chunk_list) {
 605                if (list_entry(p, struct dasd_mchunk, list) > chunk)
 606                        break;
 607                left = p;
 608        }
 609        /* Try to merge with right neighbour = next element from left. */
 610        if (left->next != chunk_list) {
 611                tmp = list_entry(left->next, struct dasd_mchunk, list);
 612                if ((char *) (chunk + 1) + chunk->size == (char *) tmp) {
 613                        list_del(&tmp->list);
 614                        chunk->size += tmp->size + sizeof(struct dasd_mchunk);
 615                }
 616        }
 617        /* Try to merge with left neighbour. */
 618        if (left != chunk_list) {
 619                tmp = list_entry(left, struct dasd_mchunk, list);
 620                if ((char *) (tmp + 1) + tmp->size == (char *) chunk) {
 621                        tmp->size += chunk->size + sizeof(struct dasd_mchunk);
 622                        return;
 623                }
 624        }
 625        __list_add(&chunk->list, left, left->next);
 626}
 627
 628/*
 629 * Check if bsize is in { 512, 1024, 2048, 4096 }
 630 */
 631static inline int
 632dasd_check_blocksize(int bsize)
 633{
 634        if (bsize < 512 || bsize > 4096 || !is_power_of_2(bsize))
 635                return -EMEDIUMTYPE;
 636        return 0;
 637}
 638
 639/* externals in dasd.c */
 640#define DASD_PROFILE_OFF         0
 641#define DASD_PROFILE_ON          1
 642#define DASD_PROFILE_GLOBAL_ONLY 2
 643
 644extern debug_info_t *dasd_debug_area;
 645extern struct dasd_profile_info dasd_global_profile_data;
 646extern unsigned int dasd_global_profile_level;
 647extern const struct block_device_operations dasd_device_operations;
 648
 649extern struct kmem_cache *dasd_page_cache;
 650
 651struct dasd_ccw_req *
 652dasd_kmalloc_request(int , int, int, struct dasd_device *);
 653struct dasd_ccw_req *
 654dasd_smalloc_request(int , int, int, struct dasd_device *);
 655void dasd_kfree_request(struct dasd_ccw_req *, struct dasd_device *);
 656void dasd_sfree_request(struct dasd_ccw_req *, struct dasd_device *);
 657void dasd_wakeup_cb(struct dasd_ccw_req *, void *);
 658
 659static inline int
 660dasd_kmalloc_set_cda(struct ccw1 *ccw, void *cda, struct dasd_device *device)
 661{
 662        return set_normalized_cda(ccw, cda);
 663}
 664
 665struct dasd_device *dasd_alloc_device(void);
 666void dasd_free_device(struct dasd_device *);
 667
 668struct dasd_block *dasd_alloc_block(void);
 669void dasd_free_block(struct dasd_block *);
 670
 671enum blk_eh_timer_return dasd_times_out(struct request *req);
 672
 673void dasd_enable_device(struct dasd_device *);
 674void dasd_set_target_state(struct dasd_device *, int);
 675void dasd_kick_device(struct dasd_device *);
 676void dasd_restore_device(struct dasd_device *);
 677void dasd_reload_device(struct dasd_device *);
 678
 679void dasd_add_request_head(struct dasd_ccw_req *);
 680void dasd_add_request_tail(struct dasd_ccw_req *);
 681int  dasd_start_IO(struct dasd_ccw_req *);
 682int  dasd_term_IO(struct dasd_ccw_req *);
 683void dasd_schedule_device_bh(struct dasd_device *);
 684void dasd_schedule_block_bh(struct dasd_block *);
 685int  dasd_sleep_on(struct dasd_ccw_req *);
 686int  dasd_sleep_on_queue(struct list_head *);
 687int  dasd_sleep_on_immediatly(struct dasd_ccw_req *);
 688int  dasd_sleep_on_interruptible(struct dasd_ccw_req *);
 689void dasd_device_set_timer(struct dasd_device *, int);
 690void dasd_device_clear_timer(struct dasd_device *);
 691void dasd_block_set_timer(struct dasd_block *, int);
 692void dasd_block_clear_timer(struct dasd_block *);
 693int  dasd_cancel_req(struct dasd_ccw_req *);
 694int dasd_flush_device_queue(struct dasd_device *);
 695int dasd_generic_probe (struct ccw_device *, struct dasd_discipline *);
 696void dasd_generic_remove (struct ccw_device *cdev);
 697int dasd_generic_set_online(struct ccw_device *, struct dasd_discipline *);
 698int dasd_generic_set_offline (struct ccw_device *cdev);
 699int dasd_generic_notify(struct ccw_device *, int);
 700int dasd_generic_last_path_gone(struct dasd_device *);
 701int dasd_generic_path_operational(struct dasd_device *);
 702void dasd_generic_shutdown(struct ccw_device *);
 703
 704void dasd_generic_handle_state_change(struct dasd_device *);
 705int dasd_generic_pm_freeze(struct ccw_device *);
 706int dasd_generic_restore_device(struct ccw_device *);
 707enum uc_todo dasd_generic_uc_handler(struct ccw_device *, struct irb *);
 708void dasd_generic_path_event(struct ccw_device *, int *);
 709int dasd_generic_verify_path(struct dasd_device *, __u8);
 710
 711int dasd_generic_read_dev_chars(struct dasd_device *, int, void *, int);
 712char *dasd_get_sense(struct irb *);
 713
 714void dasd_device_set_stop_bits(struct dasd_device *, int);
 715void dasd_device_remove_stop_bits(struct dasd_device *, int);
 716
 717int dasd_device_is_ro(struct dasd_device *);
 718
 719void dasd_profile_reset(struct dasd_profile *);
 720int dasd_profile_on(struct dasd_profile *);
 721void dasd_profile_off(struct dasd_profile *);
 722void dasd_global_profile_reset(void);
 723char *dasd_get_user_string(const char __user *, size_t);
 724
 725/* externals in dasd_devmap.c */
 726extern int dasd_max_devindex;
 727extern int dasd_probeonly;
 728extern int dasd_autodetect;
 729extern int dasd_nopav;
 730extern int dasd_nofcx;
 731
 732int dasd_devmap_init(void);
 733void dasd_devmap_exit(void);
 734
 735struct dasd_device *dasd_create_device(struct ccw_device *);
 736void dasd_delete_device(struct dasd_device *);
 737
 738int dasd_get_feature(struct ccw_device *, int);
 739int dasd_set_feature(struct ccw_device *, int, int);
 740
 741int dasd_add_sysfs_files(struct ccw_device *);
 742void dasd_remove_sysfs_files(struct ccw_device *);
 743
 744struct dasd_device *dasd_device_from_cdev(struct ccw_device *);
 745struct dasd_device *dasd_device_from_cdev_locked(struct ccw_device *);
 746struct dasd_device *dasd_device_from_devindex(int);
 747
 748void dasd_add_link_to_gendisk(struct gendisk *, struct dasd_device *);
 749struct dasd_device *dasd_device_from_gendisk(struct gendisk *);
 750
 751int dasd_parse(void);
 752int dasd_busid_known(const char *);
 753
 754/* externals in dasd_gendisk.c */
 755int  dasd_gendisk_init(void);
 756void dasd_gendisk_exit(void);
 757int dasd_gendisk_alloc(struct dasd_block *);
 758void dasd_gendisk_free(struct dasd_block *);
 759int dasd_scan_partitions(struct dasd_block *);
 760void dasd_destroy_partitions(struct dasd_block *);
 761
 762/* externals in dasd_ioctl.c */
 763int  dasd_ioctl(struct block_device *, fmode_t, unsigned int, unsigned long);
 764
 765/* externals in dasd_proc.c */
 766int dasd_proc_init(void);
 767void dasd_proc_exit(void);
 768
 769/* externals in dasd_erp.c */
 770struct dasd_ccw_req *dasd_default_erp_action(struct dasd_ccw_req *);
 771struct dasd_ccw_req *dasd_default_erp_postaction(struct dasd_ccw_req *);
 772struct dasd_ccw_req *dasd_alloc_erp_request(char *, int, int,
 773                                            struct dasd_device *);
 774void dasd_free_erp_request(struct dasd_ccw_req *, struct dasd_device *);
 775void dasd_log_sense(struct dasd_ccw_req *, struct irb *);
 776void dasd_log_sense_dbf(struct dasd_ccw_req *cqr, struct irb *irb);
 777
 778/* externals in dasd_3990_erp.c */
 779struct dasd_ccw_req *dasd_3990_erp_action(struct dasd_ccw_req *);
 780void dasd_3990_erp_handle_sim(struct dasd_device *, char *);
 781
 782/* externals in dasd_eer.c */
 783#ifdef CONFIG_DASD_EER
 784int dasd_eer_init(void);
 785void dasd_eer_exit(void);
 786int dasd_eer_enable(struct dasd_device *);
 787void dasd_eer_disable(struct dasd_device *);
 788void dasd_eer_write(struct dasd_device *, struct dasd_ccw_req *cqr,
 789                    unsigned int id);
 790void dasd_eer_snss(struct dasd_device *);
 791
 792static inline int dasd_eer_enabled(struct dasd_device *device)
 793{
 794        return device->eer_cqr != NULL;
 795}
 796#else
 797#define dasd_eer_init()         (0)
 798#define dasd_eer_exit()         do { } while (0)
 799#define dasd_eer_enable(d)      (0)
 800#define dasd_eer_disable(d)     do { } while (0)
 801#define dasd_eer_write(d,c,i)   do { } while (0)
 802#define dasd_eer_snss(d)        do { } while (0)
 803#define dasd_eer_enabled(d)     (0)
 804#endif  /* CONFIG_DASD_ERR */
 805
 806#endif                          /* DASD_H */
 807