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_COMPRESS     2
  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_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
  77     int (*bdrv_aio_multiwrite)(BlockDriverState *bs, BlockRequest *reqs,
  78         int num_reqs);
  79     int (*bdrv_merge_requests)(BlockDriverState *bs, BlockRequest* a,
  80         BlockRequest *b);
  81
  82
  83     const char *protocol_name;
  84     int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
  85     int64_t (*bdrv_getlength)(BlockDriverState *bs);
  86     int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
  87                                  const uint8_t *buf, int nb_sectors);
  88
  89     int (*bdrv_snapshot_create)(BlockDriverState *bs,
  90                                 QEMUSnapshotInfo *sn_info);
  91     int (*bdrv_snapshot_goto)(BlockDriverState *bs,
  92                               const char *snapshot_id);
  93     int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id);
  94     int (*bdrv_snapshot_list)(BlockDriverState *bs,
  95                               QEMUSnapshotInfo **psn_info);
  96     int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
  97                                   const char *snapshot_name);
  98     int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
  99
 100     int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf,
 101                              int64_t pos, int size);
 102     int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,
 103                              int64_t pos, int size);
 104
 105     int (*bdrv_change_backing_file)(BlockDriverState *bs,
 106         const char *backing_file, const char *backing_fmt);
 107
 108     /* removable device specific */
 109     int (*bdrv_is_inserted)(BlockDriverState *bs);
 110     int (*bdrv_media_changed)(BlockDriverState *bs);
 111     int (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
 112     int (*bdrv_set_locked)(BlockDriverState *bs, int locked);
 113
 114     /* to control generic scsi devices */
 115     int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);
 116     BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
 117         unsigned long int req, void *buf,
 118         BlockDriverCompletionFunc *cb, void *opaque);
 119
 120     /* List of options for creating images, terminated by name == NULL */
 121     QEMUOptionParameter *create_options;
 122
 123
 124     /*
 125      * Returns 0 for completed check, -errno for internal errors.
 126      * The check results are stored in result.
 127      */
 128     int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result);
 129
 130     void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
 131
 132     /*
 133      * Returns 1 if newly created images are guaranteed to contain only
 134      * zeros, 0 otherwise.
 135      */
 136     int (*bdrv_has_zero_init)(BlockDriverState *bs);
 137
 138     QLIST_ENTRY(BlockDriver) list;
 139 };
 140
 141 struct BlockDriverState {
 142     int64_t total_sectors; /* if we are reading a disk image, give its
 143                               size in sectors */
 144     int read_only; /* if true, the media is read only */
 145     int keep_read_only; /* if true, the media was requested to stay read only */
 146     int open_flags; /* flags used to open the file, re-used for re-open */
 147     int removable; /* if true, the media can be removed */
 148     int locked;    /* if true, the media cannot temporarily be ejected */
 149     int tray_open; /* if true, the virtual tray is open */
 150     int encrypted; /* if true, the media is encrypted */
 151     int valid_key; /* if true, a valid encryption key has been set */
 152     int sg;        /* if true, the device is a /dev/sg* */
 153     /* event callback when inserting/removing */
 154     void (*change_cb)(void *opaque);
 155     void *change_opaque;
 156
 157     BlockDriver *drv; /* NULL means no media */
 158     void *opaque;
 159
 160     DeviceState *peer;
 161
 162     char filename[1024];
 163     char backing_file[1024]; /* if non zero, the image is a diff of
 164                                 this file image */
 165     char backing_format[16]; /* if non-zero and backing_file exists */
 166     int is_temporary;
 167     int media_changed;
 168
 169     BlockDriverState *backing_hd;
 170     BlockDriverState *file;
 171
 172     /* async read/write emulation */
 173
 174     void *sync_aiocb;
 175
 176     /* I/O stats (display with "info blockstats"). */
 177     uint64_t rd_bytes;
 178     uint64_t wr_bytes;
 179     uint64_t rd_ops;
 180     uint64_t wr_ops;
 181     uint64_t wr_highest_sector;
 182
 183     /* Whether the disk can expand beyond total_sectors */
 184     int growable;
 185
 186     /* the memory alignment required for the buffers handled by this driver */
 187     int buffer_alignment;
 188
 189     /* do we need to tell the quest if we have a volatile write cache? */
 190     int enable_write_cache;
 191
 192     /* NOTE: the following infos are only hints for real hardware
 193        drivers. They are not used by the block driver */
 194     int cyls, heads, secs, translation;
 195     int type;
 196     BlockErrorAction on_read_error, on_write_error;
 197     char device_name[32];
 198     unsigned long *dirty_bitmap;
 199     int64_t dirty_count;
 200     QTAILQ_ENTRY(BlockDriverState) list;
 201     void *private;
 202 };
 203
 204 struct BlockDriverAIOCB {
 205     AIOPool *pool;
 206     BlockDriverState *bs;
 207     BlockDriverCompletionFunc *cb;
 208     void *opaque;
 209     BlockDriverAIOCB *next;
 210 };
 211
 212 void get_tmp_filename(char *filename, int size);
 213
 214 void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
 215                    BlockDriverCompletionFunc *cb, void *opaque);
 216 void qemu_aio_release(void *p);
 217
 218 void *qemu_blockalign(BlockDriverState *bs, size_t size);
 219
 220 #ifdef _WIN32
 221 int is_windows_drive(const char *filename);
 222 #endif
 223
 224 typedef struct BlockConf {
 225     BlockDriverState *bs;
 226     uint16_t physical_block_size;
 227     uint16_t logical_block_size;
 228     uint16_t min_io_size;
 229     uint32_t opt_io_size;
 230 } BlockConf;
 231
 232 static inline unsigned int get_physical_block_exp(BlockConf *conf)
 233 {
 234     unsigned int exp = 0, size;
 235
 236     for (size = conf->physical_block_size;
 237         size > conf->logical_block_size;
 238         size >>= 1) {
 239         exp++;
 240     }
 241
 242     return exp;
 243 }
 244
 245 #define DEFINE_BLOCK_PROPERTIES(_state, _conf)                          \
 246     DEFINE_PROP_DRIVE("drive", _state, _conf.bs),                       \
 247     DEFINE_PROP_UINT16("logical_block_size", _state,                    \
 248                        _conf.logical_block_size, 512),                  \
 249     DEFINE_PROP_UINT16("physical_block_size", _state,                   \
 250                        _conf.physical_block_size, 512),                 \
 251     DEFINE_PROP_UINT16("min_io_size", _state, _conf.min_io_size, 0),  \
 252     DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 0)
 253
 254 #endif /* BLOCK_INT_H */