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