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