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
  32 #define BLOCK_FLAG_ENCRYPT      1
  33 #define BLOCK_FLAG_COMPAT6      4
  34
  35 #define BLOCK_OPT_SIZE          "size"
  36 #define BLOCK_OPT_ENCRYPT       "encryption"
  37 #define BLOCK_OPT_COMPAT6       "compat6"
  38 #define BLOCK_OPT_BACKING_FILE  "backing_file"
  39 #define BLOCK_OPT_BACKING_FMT   "backing_fmt"
  40 #define BLOCK_OPT_CLUSTER_SIZE  "cluster_size"
  41 #define BLOCK_OPT_TABLE_SIZE    "table_size"
  42 #define BLOCK_OPT_PREALLOC      "preallocation"
  43 #define BLOCK_OPT_SUBFMT        "subformat"
  44
  45 typedef struct AIOPool {
  46     void (*cancel)(BlockDriverAIOCB *acb);
  47     int aiocb_size;
  48     BlockDriverAIOCB *free_aiocb;
  49 } AIOPool;
  50
  51 struct BlockDriver {
  52     const char *format_name;
  53     int instance_size;
  54     int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
  55     int (*bdrv_probe_device)(const char *filename);
  56     int (*bdrv_open)(BlockDriverState *bs, int flags);
  57     int (*bdrv_file_open)(BlockDriverState *bs, const char *filename, int flags);
  58     int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
  59                      uint8_t *buf, int nb_sectors);
  60     int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,
  61                       const uint8_t *buf, int nb_sectors);
  62     void (*bdrv_close)(BlockDriverState *bs);
  63     int (*bdrv_create)(const char *filename, QEMUOptionParameter *options);
  64     int (*bdrv_flush)(BlockDriverState *bs);
  65     int (*bdrv_is_allocated)(BlockDriverState *bs, int64_t sector_num,
  66                              int nb_sectors, int *pnum);
  67     int (*bdrv_set_key)(BlockDriverState *bs, const char *key);
  68     int (*bdrv_make_empty)(BlockDriverState *bs);
  69     /* aio */
  70     BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs,
  71         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
  72         BlockDriverCompletionFunc *cb, void *opaque);
  73     BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,
  74         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
  75         BlockDriverCompletionFunc *cb, void *opaque);
  76     BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
  77         BlockDriverCompletionFunc *cb, void *opaque);
  78     int (*bdrv_discard)(BlockDriverState *bs, int64_t sector_num,
  79                         int nb_sectors);
  80
  81     int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs,
  82         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
  83     int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs,
  84         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
  85
  86     int (*bdrv_aio_multiwrite)(BlockDriverState *bs, BlockRequest *reqs,
  87         int num_reqs);
  88     int (*bdrv_merge_requests)(BlockDriverState *bs, BlockRequest* a,
  89         BlockRequest *b);
  90
  91
  92     const char *protocol_name;
  93     int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
  94     int64_t (*bdrv_getlength)(BlockDriverState *bs);
  95     int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs);
  96     int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
  97                                  const uint8_t *buf, int nb_sectors);
  98
  99     int (*bdrv_snapshot_create)(BlockDriverState *bs,
 100                                 QEMUSnapshotInfo *sn_info);
 101     int (*bdrv_snapshot_goto)(BlockDriverState *bs,
 102                               const char *snapshot_id);
 103     int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id);
 104     int (*bdrv_snapshot_list)(BlockDriverState *bs,
 105                               QEMUSnapshotInfo **psn_info);
 106     int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
 107                                   const char *snapshot_name);
 108     int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
 109
 110     int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf,
 111                              int64_t pos, int size);
 112     int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,
 113                              int64_t pos, int size);
 114
 115     int (*bdrv_change_backing_file)(BlockDriverState *bs,
 116         const char *backing_file, const char *backing_fmt);
 117
 118     /* removable device specific */
 119     int (*bdrv_is_inserted)(BlockDriverState *bs);
 120     int (*bdrv_media_changed)(BlockDriverState *bs);
 121     void (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
 122     void (*bdrv_set_locked)(BlockDriverState *bs, int locked);
 123
 124     /* to control generic scsi devices */
 125     int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);
 126     BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
 127         unsigned long int req, void *buf,
 128         BlockDriverCompletionFunc *cb, void *opaque);
 129
 130     /* List of options for creating images, terminated by name == NULL */
 131     QEMUOptionParameter *create_options;
 132
 133
 134     /*
 135      * Returns 0 for completed check, -errno for internal errors.
 136      * The check results are stored in result.
 137      */
 138     int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result);
 139
 140     void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
 141
 142     /*
 143      * Returns 1 if newly created images are guaranteed to contain only
 144      * zeros, 0 otherwise.
 145      */
 146     int (*bdrv_has_zero_init)(BlockDriverState *bs);
 147
 148     QLIST_ENTRY(BlockDriver) list;
 149 };
 150
 151 struct BlockDriverState {
 152     int64_t total_sectors; /* if we are reading a disk image, give its
 153                               size in sectors */
 154     int read_only; /* if true, the media is read only */
 155     int keep_read_only; /* if true, the media was requested to stay read only */
 156     int open_flags; /* flags used to open the file, re-used for re-open */
 157     int removable; /* if true, the media can be removed */
 158     int locked;    /* if true, the media cannot temporarily be ejected */
 159     int tray_open; /* if true, the virtual tray is open */
 160     int encrypted; /* if true, the media is encrypted */
 161     int valid_key; /* if true, a valid encryption key has been set */
 162     int sg;        /* if true, the device is a /dev/sg* */
 163     /* event callback when inserting/removing */
 164     void (*change_cb)(void *opaque, int reason);
 165     void *change_opaque;
 166
 167     BlockDriver *drv; /* NULL means no media */
 168     void *opaque;
 169
 170     DeviceState *peer;
 171
 172     char filename[1024];
 173     char backing_file[1024]; /* if non zero, the image is a diff of
 174                                 this file image */
 175     char backing_format[16]; /* if non-zero and backing_file exists */
 176     int is_temporary;
 177     int media_changed;
 178
 179     BlockDriverState *backing_hd;
 180     BlockDriverState *file;
 181
 182     /* async read/write emulation */
 183
 184     void *sync_aiocb;
 185
 186     /* I/O stats (display with "info blockstats"). */
 187     uint64_t rd_bytes;
 188     uint64_t wr_bytes;
 189     uint64_t rd_ops;
 190     uint64_t wr_ops;
 191     uint64_t wr_highest_sector;
 192
 193     /* Whether the disk can expand beyond total_sectors */
 194     int growable;
 195
 196     /* the memory alignment required for the buffers handled by this driver */
 197     int buffer_alignment;
 198
 199     /* do we need to tell the quest if we have a volatile write cache? */
 200     int enable_write_cache;
 201
 202     /* NOTE: the following infos are only hints for real hardware
 203        drivers. They are not used by the block driver */
 204     int cyls, heads, secs, translation;
 205     BlockErrorAction on_read_error, on_write_error;
 206     char device_name[32];
 207     unsigned long *dirty_bitmap;
 208     int64_t dirty_count;
 209     int in_use; /* users other than guest access, eg. block migration */
 210     QTAILQ_ENTRY(BlockDriverState) list;
 211     void *private;
 212 };
 213
 214 #define CHANGE_MEDIA    0x01
 215 #define CHANGE_SIZE     0x02
 216
 217 struct BlockDriverAIOCB {
 218     AIOPool *pool;
 219     BlockDriverState *bs;
 220     BlockDriverCompletionFunc *cb;
 221     void *opaque;
 222     BlockDriverAIOCB *next;
 223 };
 224
 225 void get_tmp_filename(char *filename, int size);
 226
 227 void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
 228                    BlockDriverCompletionFunc *cb, void *opaque);
 229 void qemu_aio_release(void *p);
 230
 231 void *qemu_blockalign(BlockDriverState *bs, size_t size);
 232
 233 #ifdef _WIN32
 234 int is_windows_drive(const char *filename);
 235 #endif
 236
 237 typedef struct BlockConf {
 238     BlockDriverState *bs;
 239     uint16_t physical_block_size;
 240     uint16_t logical_block_size;
 241     uint16_t min_io_size;
 242     uint32_t opt_io_size;
 243     int32_t bootindex;
 244     uint32_t discard_granularity;
 245 } BlockConf;
 246
 247 static inline unsigned int get_physical_block_exp(BlockConf *conf)
 248 {
 249     unsigned int exp = 0, size;
 250
 251     for (size = conf->physical_block_size;
 252         size > conf->logical_block_size;
 253         size >>= 1) {
 254         exp++;
 255     }
 256
 257     return exp;
 258 }
 259
 260 #define DEFINE_BLOCK_PROPERTIES(_state, _conf)                          \
 261     DEFINE_PROP_DRIVE("drive", _state, _conf.bs),                       \
 262     DEFINE_PROP_UINT16("logical_block_size", _state,                    \
 263                        _conf.logical_block_size, 512),                  \
 264     DEFINE_PROP_UINT16("physical_block_size", _state,                   \
 265                        _conf.physical_block_size, 512),                 \
 266     DEFINE_PROP_UINT16("min_io_size", _state, _conf.min_io_size, 0),  \
 267     DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 0),    \
 268     DEFINE_PROP_INT32("bootindex", _state, _conf.bootindex, -1),        \
 269     DEFINE_PROP_UINT32("discard_granularity", _state, \
 270                        _conf.discard_granularity, 0)
 271
 272 #endif /* BLOCK_INT_H */