Archipelago » qemu

/*

 * QEMU System Emulator block driver

 *

 * Copyright (c) 2003 Fabrice Bellard

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#ifndef BLOCK_INT_H

#define BLOCK_INT_H

#include "block.h"

#include "qemu-option.h"

#include "qemu-queue.h"

#include "qemu-coroutine.h"

#include "qemu-timer.h"

#include "qapi-types.h"

#define BLOCK_FLAG_ENCRYPT        1

#define BLOCK_FLAG_COMPAT6        4

#define BLOCK_IO_LIMIT_READ     0

#define BLOCK_IO_LIMIT_WRITE    1

#define BLOCK_IO_LIMIT_TOTAL    2

#define BLOCK_IO_SLICE_TIME     100000000

#define NANOSECONDS_PER_SECOND  1000000000.0

#define BLOCK_OPT_SIZE          "size"

#define BLOCK_OPT_ENCRYPT       "encryption"

#define BLOCK_OPT_COMPAT6       "compat6"

#define BLOCK_OPT_BACKING_FILE  "backing_file"

#define BLOCK_OPT_BACKING_FMT   "backing_fmt"

#define BLOCK_OPT_CLUSTER_SIZE  "cluster_size"

#define BLOCK_OPT_TABLE_SIZE    "table_size"

#define BLOCK_OPT_PREALLOC      "preallocation"

#define BLOCK_OPT_SUBFMT        "subformat"

typedef struct BdrvTrackedRequest BdrvTrackedRequest;

typedef struct AIOPool {

    void (*cancel)(BlockDriverAIOCB *acb);

    int aiocb_size;

    BlockDriverAIOCB *free_aiocb;

} AIOPool;

typedef struct BlockIOLimit {

    int64_t bps[3];

    int64_t iops[3];

} BlockIOLimit;

typedef struct BlockIOBaseValue {

    uint64_t bytes[2];

    uint64_t ios[2];

} BlockIOBaseValue;

typedef void BlockJobCancelFunc(void *opaque);

typedef struct BlockJob BlockJob;

typedef struct BlockJobType {

    /** Derived BlockJob struct size */

    size_t instance_size;

    /** String describing the operation, part of query-block-jobs QMP API */

    const char *job_type;

    /** Optional callback for job types that support setting a speed limit */

    int (*set_speed)(BlockJob *job, int64_t value);

} BlockJobType;

/**

 * Long-running operation on a BlockDriverState

 */

struct BlockJob {

    const BlockJobType *job_type;

    BlockDriverState *bs;

    bool cancelled;

    /* These fields are published by the query-block-jobs QMP API */

    int64_t offset;

    int64_t len;

    int64_t speed;

    BlockDriverCompletionFunc *cb;

    void *opaque;

};

struct BlockDriver {

    const char *format_name;

    int instance_size;

    int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);

    int (*bdrv_probe_device)(const char *filename);

    int (*bdrv_open)(BlockDriverState *bs, int flags);

    int (*bdrv_file_open)(BlockDriverState *bs, const char *filename, int flags);

    int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,

                     uint8_t *buf, int nb_sectors);

    int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,

                      const uint8_t *buf, int nb_sectors);

    void (*bdrv_close)(BlockDriverState *bs);

    int (*bdrv_create)(const char *filename, QEMUOptionParameter *options);

    int (*bdrv_set_key)(BlockDriverState *bs, const char *key);

    int (*bdrv_make_empty)(BlockDriverState *bs);

    /* aio */

    BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs,

        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,

        BlockDriverCompletionFunc *cb, void *opaque);

    BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,

        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,

        BlockDriverCompletionFunc *cb, void *opaque);

    BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,

        BlockDriverCompletionFunc *cb, void *opaque);

    BlockDriverAIOCB *(*bdrv_aio_discard)(BlockDriverState *bs,

        int64_t sector_num, int nb_sectors,

        BlockDriverCompletionFunc *cb, void *opaque);

    int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs,

        int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);

    int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs,

        int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);

    /*

     * Efficiently zero a region of the disk image.  Typically an image format

     * would use a compact metadata representation to implement this.  This

     * function pointer may be NULL and .bdrv_co_writev() will be called

     * instead.

     */

    int coroutine_fn (*bdrv_co_write_zeroes)(BlockDriverState *bs,

        int64_t sector_num, int nb_sectors);

    int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs,

        int64_t sector_num, int nb_sectors);

    int coroutine_fn (*bdrv_co_is_allocated)(BlockDriverState *bs,

        int64_t sector_num, int nb_sectors, int *pnum);

    /*

     * Invalidate any cached meta-data.

     */

    void (*bdrv_invalidate_cache)(BlockDriverState *bs);

    /*

     * Flushes all data that was already written to the OS all the way down to

     * the disk (for example raw-posix calls fsync()).

     */

    int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs);

    /*

     * Flushes all internal caches to the OS. The data may still sit in a

     * writeback cache of the host OS, but it will survive a crash of the qemu

     * process.

     */

    int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs);

    int (*bdrv_aio_multiwrite)(BlockDriverState *bs, BlockRequest *reqs,

        int num_reqs);

    int (*bdrv_merge_requests)(BlockDriverState *bs, BlockRequest* a,

        BlockRequest *b);

    const char *protocol_name;

    int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);

    int64_t (*bdrv_getlength)(BlockDriverState *bs);

    int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs);

    int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,

                                 const uint8_t *buf, int nb_sectors);

    int (*bdrv_snapshot_create)(BlockDriverState *bs,

                                QEMUSnapshotInfo *sn_info);

    int (*bdrv_snapshot_goto)(BlockDriverState *bs,

                              const char *snapshot_id);

    int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id);

    int (*bdrv_snapshot_list)(BlockDriverState *bs,

                              QEMUSnapshotInfo **psn_info);

    int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,

                                  const char *snapshot_name);

    int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);

    int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf,

                             int64_t pos, int size);

    int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,

                             int64_t pos, int size);

    int (*bdrv_change_backing_file)(BlockDriverState *bs,

        const char *backing_file, const char *backing_fmt);

    /* removable device specific */

    int (*bdrv_is_inserted)(BlockDriverState *bs);

    int (*bdrv_media_changed)(BlockDriverState *bs);

    void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag);

    void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked);

    /* to control generic scsi devices */

    int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);

    BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,

        unsigned long int req, void *buf,

        BlockDriverCompletionFunc *cb, void *opaque);

    /* List of options for creating images, terminated by name == NULL */

    QEMUOptionParameter *create_options;

    /*

     * Returns 0 for completed check, -errno for internal errors.

     * The check results are stored in result.

     */

    int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result);

    void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);

    /*

     * Returns 1 if newly created images are guaranteed to contain only

     * zeros, 0 otherwise.

     */

    int (*bdrv_has_zero_init)(BlockDriverState *bs);

    QLIST_ENTRY(BlockDriver) list;

};

struct BlockDriverState {

    int64_t total_sectors; /* if we are reading a disk image, give its

                              size in sectors */

    int read_only; /* if true, the media is read only */

    int keep_read_only; /* if true, the media was requested to stay read only */

    int open_flags; /* flags used to open the file, re-used for re-open */

    int encrypted; /* if true, the media is encrypted */

    int valid_key; /* if true, a valid encryption key has been set */

    int sg;        /* if true, the device is a /dev/sg* */

    int copy_on_read; /* if true, copy read backing sectors into image

                         note this is a reference count */

    BlockDriver *drv; /* NULL means no media */

    void *opaque;

    void *dev;                  /* attached device model, if any */

    /* TODO change to DeviceState when all users are qdevified */

    const BlockDevOps *dev_ops;

    void *dev_opaque;

    char filename[1024];

    char backing_file[1024]; /* if non zero, the image is a diff of

                                this file image */

    char backing_format[16]; /* if non-zero and backing_file exists */

    int is_temporary;

    BlockDriverState *backing_hd;

    BlockDriverState *file;

    /* number of in-flight copy-on-read requests */

    unsigned int copy_on_read_in_flight;

    /* async read/write emulation */

    void *sync_aiocb;

    /* the time for latest disk I/O */

    int64_t slice_time;

    int64_t slice_start;

    int64_t slice_end;

    BlockIOLimit io_limits;

    BlockIOBaseValue  io_base;

    CoQueue      throttled_reqs;

    QEMUTimer    *block_timer;

    bool         io_limits_enabled;

    /* I/O stats (display with "info blockstats"). */

    uint64_t nr_bytes[BDRV_MAX_IOTYPE];

    uint64_t nr_ops[BDRV_MAX_IOTYPE];

    uint64_t total_time_ns[BDRV_MAX_IOTYPE];

    uint64_t wr_highest_sector;

    /* Whether the disk can expand beyond total_sectors */

    int growable;

    /* the memory alignment required for the buffers handled by this driver */

    int buffer_alignment;

    /* do we need to tell the quest if we have a volatile write cache? */

    int enable_write_cache;

    /* NOTE: the following infos are only hints for real hardware

       drivers. They are not used by the block driver */

    int cyls, heads, secs, translation;

    BlockErrorAction on_read_error, on_write_error;

    bool iostatus_enabled;

    BlockDeviceIoStatus iostatus;

    char device_name[32];

    unsigned long *dirty_bitmap;

    int64_t dirty_count;

    int in_use; /* users other than guest access, eg. block migration */

    QTAILQ_ENTRY(BlockDriverState) list;

    void *private;

    QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;

    /* long-running background operation */

    BlockJob *job;

};

struct BlockDriverAIOCB {

    AIOPool *pool;

    BlockDriverState *bs;

    BlockDriverCompletionFunc *cb;

    void *opaque;

    BlockDriverAIOCB *next;

};

void get_tmp_filename(char *filename, int size);

void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,

                   BlockDriverCompletionFunc *cb, void *opaque);

void qemu_aio_release(void *p);

void bdrv_set_io_limits(BlockDriverState *bs,

                        BlockIOLimit *io_limits);

#ifdef _WIN32

int is_windows_drive(const char *filename);

#endif

void *block_job_create(const BlockJobType *job_type, BlockDriverState *bs,

                       BlockDriverCompletionFunc *cb, void *opaque);

void block_job_complete(BlockJob *job, int ret);

int block_job_set_speed(BlockJob *job, int64_t value);

void block_job_cancel(BlockJob *job);

bool block_job_is_cancelled(BlockJob *job);

int stream_start(BlockDriverState *bs, BlockDriverState *base,

                 const char *base_id, BlockDriverCompletionFunc *cb,

                 void *opaque);

#endif /* BLOCK_INT_H */