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
  31 #define BLOCK_FLAG_ENCRYPT      1
  32 #define BLOCK_FLAG_COMPAT6      4
  33
  34 #define BLOCK_OPT_SIZE          "size"
  35 #define BLOCK_OPT_ENCRYPT       "encryption"
  36 #define BLOCK_OPT_COMPAT6       "compat6"
  37 #define BLOCK_OPT_BACKING_FILE  "backing_file"
  38 #define BLOCK_OPT_BACKING_FMT   "backing_fmt"
  39 #define BLOCK_OPT_CLUSTER_SIZE  "cluster_size"
  40 #define BLOCK_OPT_TABLE_SIZE    "table_size"
  41 #define BLOCK_OPT_PREALLOC      "preallocation"
  42
  43 typedef struct AIOPool {
  44     void (*cancel)(BlockDriverAIOCB *acb);
  45     int aiocb_size;
  46     BlockDriverAIOCB *free_aiocb;
  47 } AIOPool;
  48
  49 struct BlockDriver {
  50     const char *format_name;
  51     int instance_size;
  52     int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
  53     int (*bdrv_probe_device)(const char *filename);
  54     int (*bdrv_open)(BlockDriverState *bs, int flags);
  55     int (*bdrv_file_open)(BlockDriverState *bs, const char *filename, int flags);
  56     int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
  57                      uint8_t *buf, int nb_sectors);
  58     int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,
  59                       const uint8_t *buf, int nb_sectors);
  60     void (*bdrv_close)(BlockDriverState *bs);
  61     int (*bdrv_create)(const char *filename, QEMUOptionParameter *options);
  62     int (*bdrv_flush)(BlockDriverState *bs);
  63     int (*bdrv_is_allocated)(BlockDriverState *bs, int64_t sector_num,
  64                              int nb_sectors, int *pnum);
  65     int (*bdrv_set_key)(BlockDriverState *bs, const char *key);
  66     int (*bdrv_make_empty)(BlockDriverState *bs);
  67     /* aio */
  68     BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs,
  69         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
  70         BlockDriverCompletionFunc *cb, void *opaque);
  71     BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,
  72         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
  73         BlockDriverCompletionFunc *cb, void *opaque);
  74     BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
  75         BlockDriverCompletionFunc *cb, void *opaque);
  76     int (*bdrv_discard)(BlockDriverState *bs, int64_t sector_num,
  77                         int nb_sectors);
  78
  79     int (*bdrv_aio_multiwrite)(BlockDriverState *bs, BlockRequest *reqs,
  80         int num_reqs);
  81     int (*bdrv_merge_requests)(BlockDriverState *bs, BlockRequest* a,
  82         BlockRequest *b);
  83
  84
  85     const char *protocol_name;
  86     int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
  87     int64_t (*bdrv_getlength)(BlockDriverState *bs);
  88     int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
  89                                  const uint8_t *buf, int nb_sectors);
  90
  91     int (*bdrv_snapshot_create)(BlockDriverState *bs,
  92                                 QEMUSnapshotInfo *sn_info);
  93     int (*bdrv_snapshot_goto)(BlockDriverState *bs,
  94                               const char *snapshot_id);
  95     int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id);
  96     int (*bdrv_snapshot_list)(BlockDriverState *bs,
  97                               QEMUSnapshotInfo **psn_info);
  98     int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
  99                                   const char *snapshot_name);
 100     int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
 101
 102     int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf,
 103                              int64_t pos, int size);
 104     int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,
 105                              int64_t pos, int size);
 106
 107     int (*bdrv_change_backing_file)(BlockDriverState *bs,
 108         const char *backing_file, const char *backing_fmt);
 109
 110     /* removable device specific */
 111     int (*bdrv_is_inserted)(BlockDriverState *bs);
 112     int (*bdrv_media_changed)(BlockDriverState *bs);
 113     int (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
 114     int (*bdrv_set_locked)(BlockDriverState *bs, int locked);
 115
 116     /* to control generic scsi devices */
 117     int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);
 118     BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
 119         unsigned long int req, void *buf,
 120         BlockDriverCompletionFunc *cb, void *opaque);
 121
 122     /* List of options for creating images, terminated by name == NULL */
 123     QEMUOptionParameter *create_options;
 124
 125
 126     /*
 127      * Returns 0 for completed check, -errno for internal errors.
 128      * The check results are stored in result.
 129      */
 130     int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result);
 131
 132     void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
 133
 134     /*
 135      * Returns 1 if newly created images are guaranteed to contain only
 136      * zeros, 0 otherwise.
 137      */
 138     int (*bdrv_has_zero_init)(BlockDriverState *bs);
 139
 140     QLIST_ENTRY(BlockDriver) list;
 141 };
 142
 143 struct BlockDriverState {
 144     int64_t total_sectors; /* if we are reading a disk image, give its
 145                               size in sectors */
 146     int read_only; /* if true, the media is read only */
 147     int keep_read_only; /* if true, the media was requested to stay read only */
 148     int open_flags; /* flags used to open the file, re-used for re-open */
 149     int removable; /* if true, the media can be removed */
 150     int locked;    /* if true, the media cannot temporarily be ejected */
 151     int tray_open; /* if true, the virtual tray is open */
 152     int encrypted; /* if true, the media is encrypted */
 153     int valid_key; /* if true, a valid encryption key has been set */
 154     int sg;        /* if true, the device is a /dev/sg* */
 155     /* event callback when inserting/removing */
 156     void (*change_cb)(void *opaque, int reason);
 157     void *change_opaque;
 158
 159     BlockDriver *drv; /* NULL means no media */
 160     void *opaque;
 161
 162     DeviceState *peer;
 163
 164     char filename[1024];
 165     char backing_file[1024]; /* if non zero, the image is a diff of
 166                                 this file image */
 167     char backing_format[16]; /* if non-zero and backing_file exists */
 168     int is_temporary;
 169     int media_changed;
 170
 171     BlockDriverState *backing_hd;
 172     BlockDriverState *file;
 173
 174     /* async read/write emulation */
 175
 176     void *sync_aiocb;
 177
 178     /* I/O stats (display with "info blockstats"). */
 179     uint64_t rd_bytes;
 180     uint64_t wr_bytes;
 181     uint64_t rd_ops;
 182     uint64_t wr_ops;
 183     uint64_t wr_highest_sector;
 184
 185     /* Whether the disk can expand beyond total_sectors */
 186     int growable;
 187
 188     /* the memory alignment required for the buffers handled by this driver */
 189     int buffer_alignment;
 190
 191     /* do we need to tell the quest if we have a volatile write cache? */
 192     int enable_write_cache;
 193
 194     /* NOTE: the following infos are only hints for real hardware
 195        drivers. They are not used by the block driver */
 196     int cyls, heads, secs, translation;
 197     BlockErrorAction on_read_error, on_write_error;
 198     char device_name[32];
 199     unsigned long *dirty_bitmap;
 200     int64_t dirty_count;
 201     int in_use; /* users other than guest access, eg. block migration */
 202     QTAILQ_ENTRY(BlockDriverState) list;
 203     void *private;
 204 };
 205
 206 #define CHANGE_MEDIA    0x01
 207 #define CHANGE_SIZE     0x02
 208
 209 struct BlockDriverAIOCB {
 210     AIOPool *pool;
 211     BlockDriverState *bs;
 212     BlockDriverCompletionFunc *cb;
 213     void *opaque;
 214     BlockDriverAIOCB *next;
 215 };
 216
 217 void get_tmp_filename(char *filename, int size);
 218
 219 void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
 220                    BlockDriverCompletionFunc *cb, void *opaque);
 221 void qemu_aio_release(void *p);
 222
 223 void *qemu_blockalign(BlockDriverState *bs, size_t size);
 224
 225 #ifdef _WIN32
 226 int is_windows_drive(const char *filename);
 227 #endif
 228
 229 typedef struct BlockConf {
 230     BlockDriverState *bs;
 231     uint16_t physical_block_size;
 232     uint16_t logical_block_size;
 233     uint16_t min_io_size;
 234     uint32_t opt_io_size;
 235     int32_t bootindex;
 236     uint32_t discard_granularity;
 237 } BlockConf;
 238
 239 static inline unsigned int get_physical_block_exp(BlockConf *conf)
 240 {
 241     unsigned int exp = 0, size;
 242
 243     for (size = conf->physical_block_size;
 244         size > conf->logical_block_size;
 245         size >>= 1) {
 246         exp++;
 247     }
 248
 249     return exp;
 250 }
 251
 252 #define DEFINE_BLOCK_PROPERTIES(_state, _conf)                          \
 253     DEFINE_PROP_DRIVE("drive", _state, _conf.bs),                       \
 254     DEFINE_PROP_UINT16("logical_block_size", _state,                    \
 255                        _conf.logical_block_size, 512),                  \
 256     DEFINE_PROP_UINT16("physical_block_size", _state,                   \
 257                        _conf.physical_block_size, 512),                 \
 258     DEFINE_PROP_UINT16("min_io_size", _state, _conf.min_io_size, 0),  \
 259     DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 0),    \
 260     DEFINE_PROP_INT32("bootindex", _state, _conf.bootindex, -1),        \
 261     DEFINE_PROP_UINT32("discard_granularity", _state, \
 262                        _conf.discard_granularity, 0)
 263
 264 #endif /* BLOCK_INT_H */