block_int.h

   1 /*
   2  * QEMU System Emulator block driver
   3  *
   4  * Copyright (c) 2003 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #ifndef BLOCK_INT_H
  25 #define BLOCK_INT_H
  26
  27 #include "block.h"
  28 #include "qemu-option.h"
  29 #include "qemu-queue.h"
  30 #include "qemu-coroutine.h"
  31 #include "qemu-timer.h"
  32
  33 #define BLOCK_FLAG_ENCRYPT      1
  34 #define BLOCK_FLAG_COMPAT6      4
  35
  36 #define BLOCK_OPT_SIZE          "size"
  37 #define BLOCK_OPT_ENCRYPT       "encryption"
  38 #define BLOCK_OPT_COMPAT6       "compat6"
  39 #define BLOCK_OPT_BACKING_FILE  "backing_file"
  40 #define BLOCK_OPT_BACKING_FMT   "backing_fmt"
  41 #define BLOCK_OPT_CLUSTER_SIZE  "cluster_size"
  42 #define BLOCK_OPT_TABLE_SIZE    "table_size"
  43 #define BLOCK_OPT_PREALLOC      "preallocation"
  44 #define BLOCK_OPT_SUBFMT        "subformat"
  45
  46 typedef struct AIOPool {
  47     void (*cancel)(BlockDriverAIOCB *acb);
  48     int aiocb_size;
  49     BlockDriverAIOCB *free_aiocb;
  50 } AIOPool;
  51
  52 struct BlockDriver {
  53     const char *format_name;
  54     int instance_size;
  55     int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
  56     int (*bdrv_probe_device)(const char *filename);
  57     int (*bdrv_open)(BlockDriverState *bs, int flags);
  58     int (*bdrv_file_open)(BlockDriverState *bs, const char *filename, int flags);
  59     int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
  60                      uint8_t *buf, int nb_sectors);
  61     int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,
  62                       const uint8_t *buf, int nb_sectors);
  63     void (*bdrv_close)(BlockDriverState *bs);
  64     int (*bdrv_create)(const char *filename, QEMUOptionParameter *options);
  65     int (*bdrv_flush)(BlockDriverState *bs);
  66     int (*bdrv_is_allocated)(BlockDriverState *bs, int64_t sector_num,
  67                              int nb_sectors, int *pnum);
  68     int (*bdrv_set_key)(BlockDriverState *bs, const char *key);
  69     int (*bdrv_make_empty)(BlockDriverState *bs);
  70     /* aio */
  71     BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs,
  72         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
  73         BlockDriverCompletionFunc *cb, void *opaque);
  74     BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,
  75         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
  76         BlockDriverCompletionFunc *cb, void *opaque);
  77     BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
  78         BlockDriverCompletionFunc *cb, void *opaque);
  79     int (*bdrv_discard)(BlockDriverState *bs, int64_t sector_num,
  80                         int nb_sectors);
  81
  82     int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs,
  83         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
  84     int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs,
  85         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
  86     int coroutine_fn (*bdrv_co_flush)(BlockDriverState *bs);
  87
  88     int (*bdrv_aio_multiwrite)(BlockDriverState *bs, BlockRequest *reqs,
  89         int num_reqs);
  90     int (*bdrv_merge_requests)(BlockDriverState *bs, BlockRequest* a,
  91         BlockRequest *b);
  92
  93
  94     const char *protocol_name;
  95     int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
  96     int64_t (*bdrv_getlength)(BlockDriverState *bs);
  97     int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs);
  98     int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
  99                                  const uint8_t *buf, int nb_sectors);
 100
 101     int (*bdrv_snapshot_create)(BlockDriverState *bs,
 102                                 QEMUSnapshotInfo *sn_info);
 103     int (*bdrv_snapshot_goto)(BlockDriverState *bs,
 104                               const char *snapshot_id);
 105     int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id);
 106     int (*bdrv_snapshot_list)(BlockDriverState *bs,
 107                               QEMUSnapshotInfo **psn_info);
 108     int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
 109                                   const char *snapshot_name);
 110     int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
 111
 112     int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf,
 113                              int64_t pos, int size);
 114     int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,
 115                              int64_t pos, int size);
 116
 117     int (*bdrv_change_backing_file)(BlockDriverState *bs,
 118         const char *backing_file, const char *backing_fmt);
 119
 120     /* removable device specific */
 121     int (*bdrv_is_inserted)(BlockDriverState *bs);
 122     int (*bdrv_media_changed)(BlockDriverState *bs);
 123     void (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
 124     void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked);
 125
 126     /* to control generic scsi devices */
 127     int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);
 128     BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
 129         unsigned long int req, void *buf,
 130         BlockDriverCompletionFunc *cb, void *opaque);
 131
 132     /* List of options for creating images, terminated by name == NULL */
 133     QEMUOptionParameter *create_options;
 134
 135
 136     /*
 137      * Returns 0 for completed check, -errno for internal errors.
 138      * The check results are stored in result.
 139      */
 140     int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result);
 141
 142     void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
 143
 144     /*
 145      * Returns 1 if newly created images are guaranteed to contain only
 146      * zeros, 0 otherwise.
 147      */
 148     int (*bdrv_has_zero_init)(BlockDriverState *bs);
 149
 150     QLIST_ENTRY(BlockDriver) list;
 151 };
 152
 153 struct BlockDriverState {
 154     int64_t total_sectors; /* if we are reading a disk image, give its
 155                               size in sectors */
 156     int read_only; /* if true, the media is read only */
 157     int keep_read_only; /* if true, the media was requested to stay read only */
 158     int open_flags; /* flags used to open the file, re-used for re-open */
 159     int encrypted; /* if true, the media is encrypted */
 160     int valid_key; /* if true, a valid encryption key has been set */
 161     int sg;        /* if true, the device is a /dev/sg* */
 162
 163     BlockDriver *drv; /* NULL means no media */
 164     void *opaque;
 165
 166     void *dev;                  /* attached device model, if any */
 167     /* TODO change to DeviceState when all users are qdevified */
 168     const BlockDevOps *dev_ops;
 169     void *dev_opaque;
 170
 171     char filename[1024];
 172     char backing_file[1024]; /* if non zero, the image is a diff of
 173                                 this file image */
 174     char backing_format[16]; /* if non-zero and backing_file exists */
 175     int is_temporary;
 176
 177     BlockDriverState *backing_hd;
 178     BlockDriverState *file;
 179
 180     /* async read/write emulation */
 181
 182     void *sync_aiocb;
 183
 184     /* I/O stats (display with "info blockstats"). */
 185     uint64_t nr_bytes[BDRV_MAX_IOTYPE];
 186     uint64_t nr_ops[BDRV_MAX_IOTYPE];
 187     uint64_t total_time_ns[BDRV_MAX_IOTYPE];
 188     uint64_t wr_highest_sector;
 189
 190     /* Whether the disk can expand beyond total_sectors */
 191     int growable;
 192
 193     /* the memory alignment required for the buffers handled by this driver */
 194     int buffer_alignment;
 195
 196     /* do we need to tell the quest if we have a volatile write cache? */
 197     int enable_write_cache;
 198
 199     /* NOTE: the following infos are only hints for real hardware
 200        drivers. They are not used by the block driver */
 201     int cyls, heads, secs, translation;
 202     BlockErrorAction on_read_error, on_write_error;
 203     BlockIOStatus iostatus;
 204     char device_name[32];
 205     unsigned long *dirty_bitmap;
 206     int64_t dirty_count;
 207     int in_use; /* users other than guest access, eg. block migration */
 208     QTAILQ_ENTRY(BlockDriverState) list;
 209     void *private;
 210 };
 211
 212 struct BlockDriverAIOCB {
 213     AIOPool *pool;
 214     BlockDriverState *bs;
 215     BlockDriverCompletionFunc *cb;
 216     void *opaque;
 217     BlockDriverAIOCB *next;
 218 };
 219
 220 void get_tmp_filename(char *filename, int size);
 221
 222 void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
 223                    BlockDriverCompletionFunc *cb, void *opaque);
 224 void qemu_aio_release(void *p);
 225
 226 #ifdef _WIN32
 227 int is_windows_drive(const char *filename);
 228 #endif
 229
 230 #endif /* BLOCK_INT_H */