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