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
  30 #define BLOCK_FLAG_ENCRYPT      1
  31 #define BLOCK_FLAG_COMPRESS     2
  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_PREALLOC      "preallocation"
  41
  42 typedef struct AIOPool {
  43     void (*cancel)(BlockDriverAIOCB *acb);
  44     int aiocb_size;
  45     BlockDriverAIOCB *free_aiocb;
  46 } AIOPool;
  47
  48 struct BlockDriver {
  49     const char *format_name;
  50     int instance_size;
  51     int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
  52     int (*bdrv_probe_device)(const char *filename);
  53     int (*bdrv_open)(BlockDriverState *bs, const char *filename, int flags);
  54     int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
  55                      uint8_t *buf, int nb_sectors);
  56     int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,
  57                       const uint8_t *buf, int nb_sectors);
  58     void (*bdrv_close)(BlockDriverState *bs);
  59     int (*bdrv_create)(const char *filename, QEMUOptionParameter *options);
  60     void (*bdrv_flush)(BlockDriverState *bs);
  61     int (*bdrv_is_allocated)(BlockDriverState *bs, int64_t sector_num,
  62                              int nb_sectors, int *pnum);
  63     int (*bdrv_set_key)(BlockDriverState *bs, const char *key);
  64     int (*bdrv_make_empty)(BlockDriverState *bs);
  65     /* aio */
  66     BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs,
  67         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
  68         BlockDriverCompletionFunc *cb, void *opaque);
  69     BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,
  70         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
  71         BlockDriverCompletionFunc *cb, void *opaque);
  72     BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
  73         BlockDriverCompletionFunc *cb, void *opaque);
  74
  75     int (*bdrv_aio_multiwrite)(BlockDriverState *bs, BlockRequest *reqs,
  76         int num_reqs);
  77     int (*bdrv_merge_requests)(BlockDriverState *bs, BlockRequest* a,
  78         BlockRequest *b);
  79
  80
  81     const char *protocol_name;
  82     int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
  83     int64_t (*bdrv_getlength)(BlockDriverState *bs);
  84     int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
  85                                  const uint8_t *buf, int nb_sectors);
  86
  87     int (*bdrv_snapshot_create)(BlockDriverState *bs,
  88                                 QEMUSnapshotInfo *sn_info);
  89     int (*bdrv_snapshot_goto)(BlockDriverState *bs,
  90                               const char *snapshot_id);
  91     int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id);
  92     int (*bdrv_snapshot_list)(BlockDriverState *bs,
  93                               QEMUSnapshotInfo **psn_info);
  94     int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
  95
  96     int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf,
  97                              int64_t pos, int size);
  98     int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,
  99                              int64_t pos, int size);
 100
 101     int (*bdrv_change_backing_file)(BlockDriverState *bs,
 102         const char *backing_file, const char *backing_fmt);
 103
 104     /* removable device specific */
 105     int (*bdrv_is_inserted)(BlockDriverState *bs);
 106     int (*bdrv_media_changed)(BlockDriverState *bs);
 107     int (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
 108     int (*bdrv_set_locked)(BlockDriverState *bs, int locked);
 109
 110     /* to control generic scsi devices */
 111     int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);
 112     BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
 113         unsigned long int req, void *buf,
 114         BlockDriverCompletionFunc *cb, void *opaque);
 115
 116     /* List of options for creating images, terminated by name == NULL */
 117     QEMUOptionParameter *create_options;
 118
 119
 120     /* Returns number of errors in image, -errno for internal errors */
 121     int (*bdrv_check)(BlockDriverState* bs);
 122
 123     void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
 124
 125     /* Set if newly created images are not guaranteed to contain only zeros */
 126     int no_zero_init;
 127
 128     struct BlockDriver *next;
 129 };
 130
 131 struct BlockDriverState {
 132     int64_t total_sectors; /* if we are reading a disk image, give its
 133                               size in sectors */
 134     int read_only; /* if true, the media is read only */
 135     int keep_read_only; /* if true, the media was requested to stay read only */
 136     int open_flags; /* flags used to open the file, re-used for re-open */
 137     int removable; /* if true, the media can be removed */
 138     int locked;    /* if true, the media cannot temporarily be ejected */
 139     int encrypted; /* if true, the media is encrypted */
 140     int valid_key; /* if true, a valid encryption key has been set */
 141     int sg;        /* if true, the device is a /dev/sg* */
 142     /* event callback when inserting/removing */
 143     void (*change_cb)(void *opaque);
 144     void *change_opaque;
 145
 146     BlockDriver *drv; /* NULL means no media */
 147     void *opaque;
 148
 149     char filename[1024];
 150     char backing_file[1024]; /* if non zero, the image is a diff of
 151                                 this file image */
 152     char backing_format[16]; /* if non-zero and backing_file exists */
 153     int is_temporary;
 154     int media_changed;
 155
 156     BlockDriverState *backing_hd;
 157     /* async read/write emulation */
 158
 159     void *sync_aiocb;
 160
 161     /* I/O stats (display with "info blockstats"). */
 162     uint64_t rd_bytes;
 163     uint64_t wr_bytes;
 164     uint64_t rd_ops;
 165     uint64_t wr_ops;
 166
 167     /* Whether the disk can expand beyond total_sectors */
 168     int growable;
 169
 170     /* the memory alignment required for the buffers handled by this driver */
 171     int buffer_alignment;
 172
 173     /* do we need to tell the quest if we have a volatile write cache? */
 174     int enable_write_cache;
 175
 176     /* NOTE: the following infos are only hints for real hardware
 177        drivers. They are not used by the block driver */
 178     int cyls, heads, secs, translation;
 179     int type;
 180     char device_name[32];
 181     unsigned long *dirty_bitmap;
 182     int64_t dirty_count;
 183     BlockDriverState *next;
 184     void *private;
 185 };
 186
 187 struct BlockDriverAIOCB {
 188     AIOPool *pool;
 189     BlockDriverState *bs;
 190     BlockDriverCompletionFunc *cb;
 191     void *opaque;
 192     BlockDriverAIOCB *next;
 193 };
 194
 195 void get_tmp_filename(char *filename, int size);
 196
 197 void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
 198                    BlockDriverCompletionFunc *cb, void *opaque);
 199 void qemu_aio_release(void *p);
 200
 201 void *qemu_blockalign(BlockDriverState *bs, size_t size);
 202
 203 extern BlockDriverState *bdrv_first;
 204
 205 #ifdef _WIN32
 206 int is_windows_drive(const char *filename);
 207 #endif
 208
 209 struct DriveInfo;
 210
 211 typedef struct BlockConf {
 212     struct DriveInfo *dinfo;
 213     uint16_t physical_block_size;
 214     uint16_t logical_block_size;
 215     uint16_t min_io_size;
 216     uint32_t opt_io_size;
 217 } BlockConf;
 218
 219 static inline unsigned int get_physical_block_exp(BlockConf *conf)
 220 {
 221     unsigned int exp = 0, size;
 222
 223     for (size = conf->physical_block_size; size > 512; size >>= 1) {
 224         exp++;
 225     }
 226
 227     return exp;
 228 }
 229
 230 #define DEFINE_BLOCK_PROPERTIES(_state, _conf)                          \
 231     DEFINE_PROP_DRIVE("drive", _state, _conf.dinfo),                    \
 232     DEFINE_PROP_UINT16("logical_block_size", _state,                    \
 233                        _conf.logical_block_size, 512),                  \
 234     DEFINE_PROP_UINT16("physical_block_size", _state,                   \
 235                        _conf.physical_block_size, 512),                 \
 236     DEFINE_PROP_UINT16("min_io_size", _state, _conf.min_io_size, 512),  \
 237     DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 512)
 238
 239 #endif /* BLOCK_INT_H */