dasd_int.h

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/*
 * Author(s)......: Holger Smolinski <[email protected]>
 *          Horst Hummel <[email protected]>
 *          Martin Schwidefsky <[email protected]>
 * Bugreports.to..: <[email protected]>
 * Copyright IBM Corp. 1999, 2009
 */

#ifndef DASD_INT_H
#define DASD_INT_H

/* we keep old device allocation scheme; IOW, minors are still in 0..255 */
#define DASD_PER_MAJOR (1U << (MINORBITS - DASD_PARTN_BITS))
#define DASD_PARTN_MASK ((1 << DASD_PARTN_BITS) - 1)

/*
 * States a dasd device can have:
 *   new: the dasd_device structure is allocated.
 *   known: the discipline for the device is identified.
 *   basic: the device can do basic i/o.
 *   unfmt: the device could not be analyzed (format is unknown).
 *   ready: partition detection is done and the device is can do block io.
 *   online: the device accepts requests from the block device queue.
 *
 * Things to do for startup state transitions:
 *   new -> known: find discipline for the device and create devfs entries.
 *   known -> basic: request irq line for the device.
 *   basic -> ready: do the initial analysis, e.g. format detection,
 *                   do block device setup and detect partitions.
 *   ready -> online: schedule the device tasklet.
 * Things to do for shutdown state transitions:
 *   online -> ready: just set the new device state.
 *   ready -> basic: flush requests from the block device layer, clear
 *                   partition information and reset format information.
 *   basic -> known: terminate all requests and free irq.
 *   known -> new: remove devfs entries and forget discipline.
 */

#define DASD_STATE_NEW    0
#define DASD_STATE_KNOWN  1
#define DASD_STATE_BASIC  2
#define DASD_STATE_UNFMT  3
#define DASD_STATE_READY  4
#define DASD_STATE_ONLINE 5

#include <linux/module.h>
#include <linux/wait.h>
#include <linux/blkdev.h>
#include <linux/genhd.h>
#include <linux/hdreg.h>
#include <linux/interrupt.h>
#include <linux/log2.h>
#include <asm/ccwdev.h>
#include <linux/workqueue.h>
#include <asm/debug.h>
#include <asm/dasd.h>
#include <asm/idals.h>

/* DASD discipline magic */
#define DASD_ECKD_MAGIC 0xC5C3D2C4
#define DASD_DIAG_MAGIC 0xC4C9C1C7
#define DASD_FBA_MAGIC 0xC6C2C140

/*
 * SECTION: Type definitions
 */
struct dasd_device;
struct dasd_block;

/* BIT DEFINITIONS FOR SENSE DATA */
#define DASD_SENSE_BIT_0 0x80
#define DASD_SENSE_BIT_1 0x40
#define DASD_SENSE_BIT_2 0x20
#define DASD_SENSE_BIT_3 0x10

/* BIT DEFINITIONS FOR SIM SENSE */
#define DASD_SIM_SENSE 0x0F
#define DASD_SIM_MSG_TO_OP 0x03
#define DASD_SIM_LOG 0x0C

/* lock class for nested cdev lock */
#define CDEV_NESTED_FIRST 1
#define CDEV_NESTED_SECOND 2

/*
 * SECTION: MACROs for klogd and s390 debug feature (dbf)
 */
#define DBF_DEV_EVENT(d_level, d_device, d_str, d_data...) \
do { \
    debug_sprintf_event(d_device->debug_area, \
                d_level, \
                d_str "\n", \
                d_data); \
} while(0)

#define DBF_DEV_EXC(d_level, d_device, d_str, d_data...) \
do { \
    debug_sprintf_exception(d_device->debug_area, \
                d_level, \
                d_str "\n", \
                d_data); \
} while(0)

#define DBF_EVENT(d_level, d_str, d_data...)\
do { \
    debug_sprintf_event(dasd_debug_area, \
                d_level,\
                d_str "\n", \
                d_data); \
} while(0)

#define DBF_EVENT_DEVID(d_level, d_cdev, d_str, d_data...)  \
do { \
    struct ccw_dev_id __dev_id;         \
    ccw_device_get_id(d_cdev, &__dev_id);       \
    debug_sprintf_event(dasd_debug_area,        \
                d_level,                    \
                "0.%x.%04x " d_str "\n",            \
                __dev_id.ssid, __dev_id.devno, d_data); \
} while (0)

#define DBF_EXC(d_level, d_str, d_data...)\
do { \
    debug_sprintf_exception(dasd_debug_area, \
                d_level,\
                d_str "\n", \
                d_data); \
} while(0)

/* limit size for an errorstring */
#define ERRORLENGTH 30

/* definition of dbf debug levels */
#define DBF_EMERG   0   /* system is unusable           */
#define DBF_ALERT   1   /* action must be taken immediately */
#define DBF_CRIT    2   /* critical conditions          */
#define DBF_ERR     3   /* error conditions         */
#define DBF_WARNING 4   /* warning conditions           */
#define DBF_NOTICE  5   /* normal but significant condition */
#define DBF_INFO    6   /* informational            */
#define DBF_DEBUG   6   /* debug-level messages         */

/* messages to be written via klogd and dbf */
#define DEV_MESSAGE(d_loglevel,d_device,d_string,d_args...)\
do { \
    printk(d_loglevel PRINTK_HEADER " %s: " d_string "\n", \
           dev_name(&d_device->cdev->dev), d_args); \
    DBF_DEV_EVENT(DBF_ALERT, d_device, d_string, d_args); \
} while(0)

#define MESSAGE(d_loglevel,d_string,d_args...)\
do { \
    printk(d_loglevel PRINTK_HEADER " " d_string "\n", d_args); \
    DBF_EVENT(DBF_ALERT, d_string, d_args); \
} while(0)

/* messages to be written via klogd only */
#define DEV_MESSAGE_LOG(d_loglevel,d_device,d_string,d_args...)\
do { \
    printk(d_loglevel PRINTK_HEADER " %s: " d_string "\n", \
           dev_name(&d_device->cdev->dev), d_args); \
} while(0)

#define MESSAGE_LOG(d_loglevel,d_string,d_args...)\
do { \
    printk(d_loglevel PRINTK_HEADER " " d_string "\n", d_args); \
} while(0)

struct dasd_ccw_req {
    unsigned int magic;     /* Eye catcher */
    struct list_head devlist;   /* for dasd_device request queue */
    struct list_head blocklist; /* for dasd_block request queue */

    /* Where to execute what... */
    struct dasd_block *block;   /* the originating block device */
    struct dasd_device *memdev; /* the device used to allocate this */
    struct dasd_device *startdev;   /* device the request is started on */
    void *cpaddr;           /* address of ccw or tcw */
    unsigned char cpmode;       /* 0 = cmd mode, 1 = itcw */
    char status;            /* status of this request */
    short retries;          /* A retry counter */
    unsigned long flags;            /* flags of this request */

    /* ... and how */
    unsigned long starttime;    /* jiffies time of request start */
    unsigned long expires;      /* expiration period in jiffies */
    char lpm;           /* logical path mask */
    void *data;         /* pointer to data area */

    /* these are important for recovering erroneous requests          */
    int intrc;          /* internal error, e.g. from start_IO */
    struct irb irb;         /* device status in case of an error */
    struct dasd_ccw_req *refers;    /* ERP-chain queueing. */
    void *function;         /* originating ERP action */

    /* these are for statistics only */
    unsigned long long buildclk;    /* TOD-clock of request generation */
    unsigned long long startclk;    /* TOD-clock of request start */
    unsigned long long stopclk; /* TOD-clock of request interrupt */
    unsigned long long endclk;  /* TOD-clock of request termination */

        /* Callback that is called after reaching final status. */
    void (*callback)(struct dasd_ccw_req *, void *data);
    void *callback_data;
};

/*
 * dasd_ccw_req -> status can be:
 */
#define DASD_CQR_FILLED     0x00    /* request is ready to be processed */
#define DASD_CQR_DONE       0x01    /* request is completed successfully */
#define DASD_CQR_NEED_ERP   0x02    /* request needs recovery action */
#define DASD_CQR_IN_ERP     0x03    /* request is in recovery */
#define DASD_CQR_FAILED     0x04    /* request is finally failed */
#define DASD_CQR_TERMINATED 0x05    /* request was stopped by driver */

#define DASD_CQR_QUEUED     0x80    /* request is queued to be processed */
#define DASD_CQR_IN_IO      0x81    /* request is currently in IO */
#define DASD_CQR_ERROR      0x82    /* request is completed with error */
#define DASD_CQR_CLEAR_PENDING  0x83    /* request is clear pending */
#define DASD_CQR_CLEARED    0x84    /* request was cleared */
#define DASD_CQR_SUCCESS    0x85    /* request was successful */

/* default expiration time*/
#define DASD_EXPIRES      300
#define DASD_EXPIRES_MAX  40000000

/* per dasd_ccw_req flags */
#define DASD_CQR_FLAGS_USE_ERP   0  /* use ERP for this request */
#define DASD_CQR_FLAGS_FAILFAST  1  /* FAILFAST */
#define DASD_CQR_VERIFY_PATH     2  /* path verification request */
#define DASD_CQR_ALLOW_SLOCK     3  /* Try this request even when lock was
                     * stolen. Should not be combined with
                     * DASD_CQR_FLAGS_USE_ERP
                     */

/* Signature for error recovery functions. */
typedef struct dasd_ccw_req *(*dasd_erp_fn_t) (struct dasd_ccw_req *);

/*
 * Unique identifier for dasd device.
 */
#define UA_NOT_CONFIGURED  0x00
#define UA_BASE_DEVICE     0x01
#define UA_BASE_PAV_ALIAS  0x02
#define UA_HYPER_PAV_ALIAS 0x03

struct dasd_uid {
    __u8 type;
    char vendor[4];
    char serial[15];
    __u16 ssid;
    __u8 real_unit_addr;
    __u8 base_unit_addr;
    char vduit[33];
};

/*
 * the struct dasd_discipline is
 * sth like a table of virtual functions, if you think of dasd_eckd
 * inheriting dasd...
 * no, currently we are not planning to reimplement the driver in C++
 */
struct dasd_discipline {
    struct module *owner;
    char ebcname[8];    /* a name used for tagging and printks */
    char name[8];       /* a name used for tagging and printks */
    int max_blocks;     /* maximum number of blocks to be chained */

    struct list_head list;  /* used for list of disciplines */

    /*
     * Device recognition functions. check_device is used to verify
     * the sense data and the information returned by read device
     * characteristics. It returns 0 if the discipline can be used
     * for the device in question. uncheck_device is called during
     * device shutdown to deregister a device from its discipline.
     */
    int (*check_device) (struct dasd_device *);
    void (*uncheck_device) (struct dasd_device *);

    /*
     * do_analysis is used in the step from device state "basic" to
     * state "accept". It returns 0 if the device can be made ready,
     * it returns -EMEDIUMTYPE if the device can't be made ready or
     * -EAGAIN if do_analysis started a ccw that needs to complete
     * before the analysis may be repeated.
     */
    int (*do_analysis) (struct dasd_block *);

    /*
     * This function is called, when new paths become available.
     * Disciplins may use this callback to do necessary setup work,
     * e.g. verify that new path is compatible with the current
     * configuration.
     */
    int (*verify_path)(struct dasd_device *, __u8);

    /*
     * Last things to do when a device is set online, and first things
     * when it is set offline.
     */
    int (*ready_to_online) (struct dasd_device *);
    int (*online_to_ready) (struct dasd_device *);

    /*
     * Device operation functions. build_cp creates a ccw chain for
     * a block device request, start_io starts the request and
     * term_IO cancels it (e.g. in case of a timeout). format_device
     * returns a ccw chain to be used to format the device.
     * handle_terminated_request allows to examine a cqr and prepare
     * it for retry.
     */
    struct dasd_ccw_req *(*build_cp) (struct dasd_device *,
                      struct dasd_block *,
                      struct request *);
    int (*start_IO) (struct dasd_ccw_req *);
    int (*term_IO) (struct dasd_ccw_req *);
    void (*handle_terminated_request) (struct dasd_ccw_req *);
    struct dasd_ccw_req *(*format_device) (struct dasd_device *,
                           struct format_data_t *);
    int (*free_cp) (struct dasd_ccw_req *, struct request *);

    /*
     * Error recovery functions. examine_error() returns a value that
     * indicates what to do for an error condition. If examine_error()
     * returns 'dasd_era_recover' erp_action() is called to create a
     * special error recovery ccw. erp_postaction() is called after
     * an error recovery ccw has finished its execution. dump_sense
     * is called for every error condition to print the sense data
     * to the console.
     */
    dasd_erp_fn_t(*erp_action) (struct dasd_ccw_req *);
    dasd_erp_fn_t(*erp_postaction) (struct dasd_ccw_req *);
    void (*dump_sense) (struct dasd_device *, struct dasd_ccw_req *,
                struct irb *);
    void (*dump_sense_dbf) (struct dasd_device *, struct irb *, char *);
    void (*check_for_device_change) (struct dasd_device *,
                     struct dasd_ccw_req *,
                     struct irb *);

        /* i/o control functions. */
    int (*fill_geometry) (struct dasd_block *, struct hd_geometry *);
    int (*fill_info) (struct dasd_device *, struct dasd_information2_t *);
    int (*ioctl) (struct dasd_block *, unsigned int, void __user *);

    /* suspend/resume functions */
    int (*freeze) (struct dasd_device *);
    int (*restore) (struct dasd_device *);

    /* reload device after state change */
    int (*reload) (struct dasd_device *);

    int (*get_uid) (struct dasd_device *, struct dasd_uid *);
    void (*kick_validate) (struct dasd_device *);
};

extern struct dasd_discipline *dasd_diag_discipline_pointer;

/*
 * Notification numbers for extended error reporting notifications:
 * The DASD_EER_DISABLE notification is sent before a dasd_device (and it's
 * eer pointer) is freed. The error reporting module needs to do all necessary
 * cleanup steps.
 * The DASD_EER_TRIGGER notification sends the actual error reports (triggers).
 */
#define DASD_EER_DISABLE 0
#define DASD_EER_TRIGGER 1

/* Trigger IDs for extended error reporting DASD_EER_TRIGGER notification */
#define DASD_EER_FATALERROR  1
#define DASD_EER_NOPATH      2
#define DASD_EER_STATECHANGE 3
#define DASD_EER_PPRCSUSPEND 4

struct dasd_path {
    __u8 opm;
    __u8 tbvpm;
    __u8 ppm;
    __u8 npm;
};

struct dasd_profile_info {
    /* legacy part of profile data, as in dasd_profile_info_t */
    unsigned int dasd_io_reqs;   /* number of requests processed */
    unsigned int dasd_io_sects;  /* number of sectors processed */
    unsigned int dasd_io_secs[32];   /* histogram of request's sizes */
    unsigned int dasd_io_times[32];  /* histogram of requests's times */
    unsigned int dasd_io_timps[32];  /* h. of requests's times per sector */
    unsigned int dasd_io_time1[32];  /* hist. of time from build to start */
    unsigned int dasd_io_time2[32];  /* hist. of time from start to irq */
    unsigned int dasd_io_time2ps[32]; /* hist. of time from start to irq */
    unsigned int dasd_io_time3[32];  /* hist. of time from irq to end */
    unsigned int dasd_io_nr_req[32]; /* hist. of # of requests in chanq */

    /* new data */
    struct timespec starttod;      /* time of start or last reset */
    unsigned int dasd_io_alias;    /* requests using an alias */
    unsigned int dasd_io_tpm;      /* requests using transport mode */
    unsigned int dasd_read_reqs;       /* total number of read  requests */
    unsigned int dasd_read_sects;      /* total number read sectors */
    unsigned int dasd_read_alias;      /* read request using an alias */
    unsigned int dasd_read_tpm;    /* read requests in transport mode */
    unsigned int dasd_read_secs[32];   /* histogram of request's sizes */
    unsigned int dasd_read_times[32];  /* histogram of requests's times */
    unsigned int dasd_read_time1[32];  /* hist. time from build to start */
    unsigned int dasd_read_time2[32];  /* hist. of time from start to irq */
    unsigned int dasd_read_time3[32];  /* hist. of time from irq to end */
    unsigned int dasd_read_nr_req[32]; /* hist. of # of requests in chanq */
};

struct dasd_profile {
    struct dentry *dentry;
    struct dasd_profile_info *data;
    spinlock_t lock;
};

struct dasd_device {
    /* Block device stuff. */
    struct dasd_block *block;

        unsigned int devindex;
    unsigned long flags;       /* per device flags */
    unsigned short features;   /* copy of devmap-features (read-only!) */

    /* extended error reporting stuff (eer) */
    struct dasd_ccw_req *eer_cqr;

    /* Device discipline stuff. */
    struct dasd_discipline *discipline;
    struct dasd_discipline *base_discipline;
    char *private;
    struct dasd_path path_data;

    /* Device state and target state. */
    int state, target;
    struct mutex state_mutex;
    int stopped;        /* device (ccw_device_start) was stopped */

    /* reference count. */
        atomic_t ref_count;

    /* ccw queue and memory for static ccw/erp buffers. */
    struct list_head ccw_queue;
    spinlock_t mem_lock;
    void *ccw_mem;
    void *erp_mem;
    struct list_head ccw_chunks;
    struct list_head erp_chunks;

    atomic_t tasklet_scheduled;
        struct tasklet_struct tasklet;
    struct work_struct kick_work;
    struct work_struct restore_device;
    struct work_struct reload_device;
    struct work_struct kick_validate;
    struct timer_list timer;

    debug_info_t *debug_area;

    struct ccw_device *cdev;

    /* hook for alias management */
    struct list_head alias_list;

    /* default expiration time in s */
    unsigned long default_expires;

    struct dentry *debugfs_dentry;
    struct dasd_profile profile;
};

struct dasd_block {
    /* Block device stuff. */
    struct gendisk *gdp;
    struct request_queue *request_queue;
    spinlock_t request_queue_lock;
    struct block_device *bdev;
    atomic_t open_count;

    unsigned long long blocks; /* size of volume in blocks */
    unsigned int bp_block;     /* bytes per block */
    unsigned int s2b_shift;    /* log2 (bp_block/512) */

    struct dasd_device *base;
    struct list_head ccw_queue;
    spinlock_t queue_lock;

    atomic_t tasklet_scheduled;
    struct tasklet_struct tasklet;
    struct timer_list timer;

    struct dentry *debugfs_dentry;
    struct dasd_profile profile;
};



/* reasons why device (ccw_device_start) was stopped */
#define DASD_STOPPED_NOT_ACC 1         /* not accessible */
#define DASD_STOPPED_QUIESCE 2         /* Quiesced */
#define DASD_STOPPED_PENDING 4         /* long busy */
#define DASD_STOPPED_DC_WAIT 8         /* disconnected, wait */
#define DASD_STOPPED_SU      16        /* summary unit check handling */
#define DASD_STOPPED_PM      32        /* pm state transition */
#define DASD_UNRESUMED_PM    64        /* pm resume failed state */

/* per device flags */
#define DASD_FLAG_OFFLINE   3   /* device is in offline processing */
#define DASD_FLAG_EER_SNSS  4   /* A SNSS is required */
#define DASD_FLAG_EER_IN_USE    5   /* A SNSS request is running */
#define DASD_FLAG_DEVICE_RO 6   /* The device itself is read-only. Don't
                     * confuse this with the user specified
                     * read-only feature.
                     */
#define DASD_FLAG_IS_RESERVED   7   /* The device is reserved */
#define DASD_FLAG_LOCK_STOLEN   8   /* The device lock was stolen */
#define DASD_FLAG_SUSPENDED 9   /* The device was suspended */


void dasd_put_device_wake(struct dasd_device *);

/*
 * Reference count inliners
 */
static inline void
dasd_get_device(struct dasd_device *device)
{
    atomic_inc(&device->ref_count);
}

static inline void
dasd_put_device(struct dasd_device *device)
{
    if (atomic_dec_return(&device->ref_count) == 0)
        dasd_put_device_wake(device);
}

/*
 * The static memory in ccw_mem and erp_mem is managed by a sorted
 * list of free memory chunks.
 */
struct dasd_mchunk
{
    struct list_head list;
    unsigned long size;
} __attribute__ ((aligned(8)));

static inline void
dasd_init_chunklist(struct list_head *chunk_list, void *mem,
            unsigned long size)
{
    struct dasd_mchunk *chunk;

    INIT_LIST_HEAD(chunk_list);
    chunk = (struct dasd_mchunk *) mem;
    chunk->size = size - sizeof(struct dasd_mchunk);
    list_add(&chunk->list, chunk_list);
}

static inline void *
dasd_alloc_chunk(struct list_head *chunk_list, unsigned long size)
{
    struct dasd_mchunk *chunk, *tmp;

    size = (size + 7L) & -8L;
    list_for_each_entry(chunk, chunk_list, list) {
        if (chunk->size < size)
            continue;
        if (chunk->size > size + sizeof(struct dasd_mchunk)) {
            char *endaddr = (char *) (chunk + 1) + chunk->size;
            tmp = (struct dasd_mchunk *) (endaddr - size) - 1;
            tmp->size = size;
            chunk->size -= size + sizeof(struct dasd_mchunk);
            chunk = tmp;
        } else
            list_del(&chunk->list);
        return (void *) (chunk + 1);
    }
    return NULL;
}

static inline void
dasd_free_chunk(struct list_head *chunk_list, void *mem)
{
    struct dasd_mchunk *chunk, *tmp;
    struct list_head *p, *left;

    chunk = (struct dasd_mchunk *)
        ((char *) mem - sizeof(struct dasd_mchunk));
    /* Find out the left neighbour in chunk_list. */
    left = chunk_list;
    list_for_each(p, chunk_list) {
        if (list_entry(p, struct dasd_mchunk, list) > chunk)
            break;
        left = p;
    }
    /* Try to merge with right neighbour = next element from left. */
    if (left->next != chunk_list) {
        tmp = list_entry(left->next, struct dasd_mchunk, list);
        if ((char *) (chunk + 1) + chunk->size == (char *) tmp) {
            list_del(&tmp->list);
            chunk->size += tmp->size + sizeof(struct dasd_mchunk);
        }
    }
    /* Try to merge with left neighbour. */
    if (left != chunk_list) {
        tmp = list_entry(left, struct dasd_mchunk, list);
        if ((char *) (tmp + 1) + tmp->size == (char *) chunk) {
            tmp->size += chunk->size + sizeof(struct dasd_mchunk);
            return;
        }
    }
    __list_add(&chunk->list, left, left->next);
}

/*
 * Check if bsize is in { 512, 1024, 2048, 4096 }
 */
static inline int
dasd_check_blocksize(int bsize)
{
    if (bsize < 512 || bsize > 4096 || !is_power_of_2(bsize))
        return -EMEDIUMTYPE;
    return 0;
}

/* externals in dasd.c */
#define DASD_PROFILE_OFF     0
#define DASD_PROFILE_ON      1
#define DASD_PROFILE_GLOBAL_ONLY 2

extern debug_info_t *dasd_debug_area;
extern struct dasd_profile_info dasd_global_profile_data;
extern unsigned int dasd_global_profile_level;
extern const struct block_device_operations dasd_device_operations;

extern struct kmem_cache *dasd_page_cache;

struct dasd_ccw_req *
dasd_kmalloc_request(int , int, int, struct dasd_device *);
struct dasd_ccw_req *
dasd_smalloc_request(int , int, int, struct dasd_device *);
void dasd_kfree_request(struct dasd_ccw_req *, struct dasd_device *);
void dasd_sfree_request(struct dasd_ccw_req *, struct dasd_device *);
void dasd_wakeup_cb(struct dasd_ccw_req *, void *);

static inline int
dasd_kmalloc_set_cda(struct ccw1 *ccw, void *cda, struct dasd_device *device)
{
    return set_normalized_cda(ccw, cda);
}

struct dasd_device *dasd_alloc_device(void);
void dasd_free_device(struct dasd_device *);

struct dasd_block *dasd_alloc_block(void);
void dasd_free_block(struct dasd_block *);

void dasd_enable_device(struct dasd_device *);
void dasd_set_target_state(struct dasd_device *, int);
void dasd_kick_device(struct dasd_device *);
void dasd_restore_device(struct dasd_device *);
void dasd_reload_device(struct dasd_device *);

void dasd_add_request_head(struct dasd_ccw_req *);
void dasd_add_request_tail(struct dasd_ccw_req *);
int  dasd_start_IO(struct dasd_ccw_req *);
int  dasd_term_IO(struct dasd_ccw_req *);
void dasd_schedule_device_bh(struct dasd_device *);
void dasd_schedule_block_bh(struct dasd_block *);
int  dasd_sleep_on(struct dasd_ccw_req *);
int  dasd_sleep_on_immediatly(struct dasd_ccw_req *);
int  dasd_sleep_on_interruptible(struct dasd_ccw_req *);
void dasd_device_set_timer(struct dasd_device *, int);
void dasd_device_clear_timer(struct dasd_device *);
void dasd_block_set_timer(struct dasd_block *, int);
void dasd_block_clear_timer(struct dasd_block *);
int  dasd_cancel_req(struct dasd_ccw_req *);
int dasd_flush_device_queue(struct dasd_device *);
int dasd_generic_probe (struct ccw_device *, struct dasd_discipline *);
void dasd_generic_remove (struct ccw_device *cdev);
int dasd_generic_set_online(struct ccw_device *, struct dasd_discipline *);
int dasd_generic_set_offline (struct ccw_device *cdev);
int dasd_generic_notify(struct ccw_device *, int);
int dasd_generic_last_path_gone(struct dasd_device *);
int dasd_generic_path_operational(struct dasd_device *);
void dasd_generic_shutdown(struct ccw_device *);

void dasd_generic_handle_state_change(struct dasd_device *);
int dasd_generic_pm_freeze(struct ccw_device *);
int dasd_generic_restore_device(struct ccw_device *);
enum uc_todo dasd_generic_uc_handler(struct ccw_device *, struct irb *);
void dasd_generic_path_event(struct ccw_device *, int *);
int dasd_generic_verify_path(struct dasd_device *, __u8);

int dasd_generic_read_dev_chars(struct dasd_device *, int, void *, int);
char *dasd_get_sense(struct irb *);

void dasd_device_set_stop_bits(struct dasd_device *, int);
void dasd_device_remove_stop_bits(struct dasd_device *, int);

int dasd_device_is_ro(struct dasd_device *);

void dasd_profile_reset(struct dasd_profile *);
int dasd_profile_on(struct dasd_profile *);
void dasd_profile_off(struct dasd_profile *);
void dasd_global_profile_reset(void);
char *dasd_get_user_string(const char __user *, size_t);

/* externals in dasd_devmap.c */
extern int dasd_max_devindex;
extern int dasd_probeonly;
extern int dasd_autodetect;
extern int dasd_nopav;
extern int dasd_nofcx;

int dasd_devmap_init(void);
void dasd_devmap_exit(void);

struct dasd_device *dasd_create_device(struct ccw_device *);
void dasd_delete_device(struct dasd_device *);

int dasd_get_feature(struct ccw_device *, int);
int dasd_set_feature(struct ccw_device *, int, int);

int dasd_add_sysfs_files(struct ccw_device *);
void dasd_remove_sysfs_files(struct ccw_device *);

struct dasd_device *dasd_device_from_cdev(struct ccw_device *);
struct dasd_device *dasd_device_from_cdev_locked(struct ccw_device *);
struct dasd_device *dasd_device_from_devindex(int);

void dasd_add_link_to_gendisk(struct gendisk *, struct dasd_device *);
struct dasd_device *dasd_device_from_gendisk(struct gendisk *);

int dasd_parse(void);
int dasd_busid_known(const char *);

/* externals in dasd_gendisk.c */
int  dasd_gendisk_init(void);
void dasd_gendisk_exit(void);
int dasd_gendisk_alloc(struct dasd_block *);
void dasd_gendisk_free(struct dasd_block *);
int dasd_scan_partitions(struct dasd_block *);
void dasd_destroy_partitions(struct dasd_block *);

/* externals in dasd_ioctl.c */
int  dasd_ioctl(struct block_device *, fmode_t, unsigned int, unsigned long);

/* externals in dasd_proc.c */
int dasd_proc_init(void);
void dasd_proc_exit(void);

/* externals in dasd_erp.c */
struct dasd_ccw_req *dasd_default_erp_action(struct dasd_ccw_req *);
struct dasd_ccw_req *dasd_default_erp_postaction(struct dasd_ccw_req *);
struct dasd_ccw_req *dasd_alloc_erp_request(char *, int, int,
                        struct dasd_device *);
void dasd_free_erp_request(struct dasd_ccw_req *, struct dasd_device *);
void dasd_log_sense(struct dasd_ccw_req *, struct irb *);
void dasd_log_sense_dbf(struct dasd_ccw_req *cqr, struct irb *irb);

/* externals in dasd_3990_erp.c */
struct dasd_ccw_req *dasd_3990_erp_action(struct dasd_ccw_req *);
void dasd_3990_erp_handle_sim(struct dasd_device *, char *);

/* externals in dasd_eer.c */
#ifdef CONFIG_DASD_EER
int dasd_eer_init(void);
void dasd_eer_exit(void);
int dasd_eer_enable(struct dasd_device *);
void dasd_eer_disable(struct dasd_device *);
void dasd_eer_write(struct dasd_device *, struct dasd_ccw_req *cqr,
            unsigned int id);
void dasd_eer_snss(struct dasd_device *);

static inline int dasd_eer_enabled(struct dasd_device *device)
{
    return device->eer_cqr != NULL;
}
#else
#define dasd_eer_init()     (0)
#define dasd_eer_exit()     do { } while (0)
#define dasd_eer_enable(d)  (0)
#define dasd_eer_disable(d) do { } while (0)
#define dasd_eer_write(d,c,i)   do { } while (0)
#define dasd_eer_snss(d)    do { } while (0)
#define dasd_eer_enabled(d) (0)
#endif  /* CONFIG_DASD_ERR */

#endif              /* DASD_H */