summaryrefslogtreecommitdiff
path: root/include/block/block_int.h
blob: 211087aa9170f8f9a583877360391c16c2715b9b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
/*
 * QEMU System Emulator block driver
 *
 * Copyright (c) 2003 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#ifndef BLOCK_INT_H
#define BLOCK_INT_H

#include "block/block.h"
#include "qemu/option.h"
#include "qemu/queue.h"
#include "block/coroutine.h"
#include "qemu/timer.h"
#include "qapi-types.h"
#include "qapi/qmp/qerror.h"
#include "monitor/monitor.h"
#include "qemu/hbitmap.h"
#include "block/snapshot.h"
#include "qemu/main-loop.h"
#include "qemu/throttle.h"

#define BLOCK_FLAG_ENCRYPT          1
#define BLOCK_FLAG_COMPAT6          4
#define BLOCK_FLAG_LAZY_REFCOUNTS   8

#define BLOCK_OPT_SIZE              "size"
#define BLOCK_OPT_ENCRYPT           "encryption"
#define BLOCK_OPT_COMPAT6           "compat6"
#define BLOCK_OPT_BACKING_FILE      "backing_file"
#define BLOCK_OPT_BACKING_FMT       "backing_fmt"
#define BLOCK_OPT_CLUSTER_SIZE      "cluster_size"
#define BLOCK_OPT_TABLE_SIZE        "table_size"
#define BLOCK_OPT_PREALLOC          "preallocation"
#define BLOCK_OPT_SUBFMT            "subformat"
#define BLOCK_OPT_COMPAT_LEVEL      "compat"
#define BLOCK_OPT_LAZY_REFCOUNTS    "lazy_refcounts"
#define BLOCK_OPT_ADAPTER_TYPE      "adapter_type"

typedef struct BdrvTrackedRequest {
    BlockDriverState *bs;
    int64_t sector_num;
    int nb_sectors;
    bool is_write;
    QLIST_ENTRY(BdrvTrackedRequest) list;
    Coroutine *co; /* owner, used for deadlock detection */
    CoQueue wait_queue; /* coroutines blocked on this request */
} BdrvTrackedRequest;

struct BlockDriver {
    const char *format_name;
    int instance_size;
    int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
    int (*bdrv_probe_device)(const char *filename);

    /* Any driver implementing this callback is expected to be able to handle
     * NULL file names in its .bdrv_open() implementation */
    void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp);
    /* Drivers not implementing bdrv_parse_filename nor bdrv_open should have
     * this field set to true, except ones that are defined only by their
     * child's bs.
     * An example of the last type will be the quorum block driver.
     */
    bool bdrv_needs_filename;

    /* For handling image reopen for split or non-split files */
    int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state,
                               BlockReopenQueue *queue, Error **errp);
    void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state);
    void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state);

    int (*bdrv_open)(BlockDriverState *bs, QDict *options, int flags,
                     Error **errp);
    int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags,
                          Error **errp);
    int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
                     uint8_t *buf, int nb_sectors);
    int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,
                      const uint8_t *buf, int nb_sectors);
    void (*bdrv_close)(BlockDriverState *bs);
    void (*bdrv_rebind)(BlockDriverState *bs);
    int (*bdrv_create)(const char *filename, QEMUOptionParameter *options,
                       Error **errp);
    int (*bdrv_set_key)(BlockDriverState *bs, const char *key);
    int (*bdrv_make_empty)(BlockDriverState *bs);
    /* aio */
    BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs,
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
        BlockDriverCompletionFunc *cb, void *opaque);
    BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
        BlockDriverCompletionFunc *cb, void *opaque);
    BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
        BlockDriverCompletionFunc *cb, void *opaque);
    BlockDriverAIOCB *(*bdrv_aio_discard)(BlockDriverState *bs,
        int64_t sector_num, int nb_sectors,
        BlockDriverCompletionFunc *cb, void *opaque);

    int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs,
        int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
    int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs,
        int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
    /*
     * Efficiently zero a region of the disk image.  Typically an image format
     * would use a compact metadata representation to implement this.  This
     * function pointer may be NULL and .bdrv_co_writev() will be called
     * instead.
     */
    int coroutine_fn (*bdrv_co_write_zeroes)(BlockDriverState *bs,
        int64_t sector_num, int nb_sectors);
    int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs,
        int64_t sector_num, int nb_sectors);
    int64_t coroutine_fn (*bdrv_co_get_block_status)(BlockDriverState *bs,
        int64_t sector_num, int nb_sectors, int *pnum);

    /*
     * Invalidate any cached meta-data.
     */
    void (*bdrv_invalidate_cache)(BlockDriverState *bs);

    /*
     * Flushes all data that was already written to the OS all the way down to
     * the disk (for example raw-posix calls fsync()).
     */
    int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs);

    /*
     * Flushes all internal caches to the OS. The data may still sit in a
     * writeback cache of the host OS, but it will survive a crash of the qemu
     * process.
     */
    int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs);

    const char *protocol_name;
    int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
    int64_t (*bdrv_getlength)(BlockDriverState *bs);
    int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs);
    int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
                                 const uint8_t *buf, int nb_sectors);

    int (*bdrv_snapshot_create)(BlockDriverState *bs,
                                QEMUSnapshotInfo *sn_info);
    int (*bdrv_snapshot_goto)(BlockDriverState *bs,
                              const char *snapshot_id);
    int (*bdrv_snapshot_delete)(BlockDriverState *bs,
                                const char *snapshot_id,
                                const char *name,
                                Error **errp);
    int (*bdrv_snapshot_list)(BlockDriverState *bs,
                              QEMUSnapshotInfo **psn_info);
    int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
                                  const char *snapshot_name);
    int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);

    int (*bdrv_save_vmstate)(BlockDriverState *bs, QEMUIOVector *qiov,
                             int64_t pos);
    int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,
                             int64_t pos, int size);

    int (*bdrv_change_backing_file)(BlockDriverState *bs,
        const char *backing_file, const char *backing_fmt);

    /* removable device specific */
    int (*bdrv_is_inserted)(BlockDriverState *bs);
    int (*bdrv_media_changed)(BlockDriverState *bs);
    void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag);
    void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked);

    /* to control generic scsi devices */
    int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);
    BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
        unsigned long int req, void *buf,
        BlockDriverCompletionFunc *cb, void *opaque);

    /* List of options for creating images, terminated by name == NULL */
    QEMUOptionParameter *create_options;


    /*
     * Returns 0 for completed check, -errno for internal errors.
     * The check results are stored in result.
     */
    int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result,
        BdrvCheckMode fix);

    int (*bdrv_amend_options)(BlockDriverState *bs,
        QEMUOptionParameter *options);

    void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);

    /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */
    int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event,
        const char *tag);
    int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag);
    bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag);

    /*
     * Returns 1 if newly created images are guaranteed to contain only
     * zeros, 0 otherwise.
     */
    int (*bdrv_has_zero_init)(BlockDriverState *bs);

    QLIST_ENTRY(BlockDriver) list;
};

/*
 * Note: the function bdrv_append() copies and swaps contents of
 * BlockDriverStates, so if you add new fields to this struct, please
 * inspect bdrv_append() to determine if the new fields need to be
 * copied as well.
 */
struct BlockDriverState {
    int64_t total_sectors; /* if we are reading a disk image, give its
                              size in sectors */
    int read_only; /* if true, the media is read only */
    int open_flags; /* flags used to open the file, re-used for re-open */
    int encrypted; /* if true, the media is encrypted */
    int valid_key; /* if true, a valid encryption key has been set */
    int sg;        /* if true, the device is a /dev/sg* */
    int copy_on_read; /* if true, copy read backing sectors into image
                         note this is a reference count */

    BlockDriver *drv; /* NULL means no media */
    void *opaque;

    void *dev;                  /* attached device model, if any */
    /* TODO change to DeviceState when all users are qdevified */
    const BlockDevOps *dev_ops;
    void *dev_opaque;

    char filename[1024];
    char backing_file[1024]; /* if non zero, the image is a diff of
                                this file image */
    char backing_format[16]; /* if non-zero and backing_file exists */
    int is_temporary;

    BlockDriverState *backing_hd;
    BlockDriverState *file;

    NotifierList close_notifiers;

    /* Callback before write request is processed */
    NotifierWithReturnList before_write_notifiers;

    /* number of in-flight copy-on-read requests */
    unsigned int copy_on_read_in_flight;

    /* I/O throttling */
    ThrottleState throttle_state;
    CoQueue      throttled_reqs[2];
    bool         io_limits_enabled;

    /* I/O stats (display with "info blockstats"). */
    uint64_t nr_bytes[BDRV_MAX_IOTYPE];
    uint64_t nr_ops[BDRV_MAX_IOTYPE];
    uint64_t total_time_ns[BDRV_MAX_IOTYPE];
    uint64_t wr_highest_sector;

    /* Whether the disk can expand beyond total_sectors */
    int growable;

    /* Whether produces zeros when read beyond eof */
    bool zero_beyond_eof;

    /* the memory alignment required for the buffers handled by this driver */
    int buffer_alignment;

    /* do we need to tell the quest if we have a volatile write cache? */
    int enable_write_cache;

    /* NOTE: the following infos are only hints for real hardware
       drivers. They are not used by the block driver */
    BlockdevOnError on_read_error, on_write_error;
    bool iostatus_enabled;
    BlockDeviceIoStatus iostatus;
    char device_name[32];
    HBitmap *dirty_bitmap;
    int refcnt;
    int in_use; /* users other than guest access, eg. block migration */
    QTAILQ_ENTRY(BlockDriverState) list;

    QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;

    /* long-running background operation */
    BlockJob *job;

    QDict *options;
};

int get_tmp_filename(char *filename, int size);

void bdrv_set_io_limits(BlockDriverState *bs,
                        ThrottleConfig *cfg);


/**
 * bdrv_add_before_write_notifier:
 *
 * Register a callback that is invoked before write requests are processed but
 * after any throttling or waiting for overlapping requests.
 */
void bdrv_add_before_write_notifier(BlockDriverState *bs,
                                    NotifierWithReturn *notifier);

/**
 * bdrv_get_aio_context:
 *
 * Returns: the currently bound #AioContext
 */
AioContext *bdrv_get_aio_context(BlockDriverState *bs);

#ifdef _WIN32
int is_windows_drive(const char *filename);
#endif
void bdrv_emit_qmp_error_event(const BlockDriverState *bdrv,
                               enum MonitorEvent ev,
                               BlockErrorAction action, bool is_read);

/**
 * stream_start:
 * @bs: Block device to operate on.
 * @base: Block device that will become the new base, or %NULL to
 * flatten the whole backing file chain onto @bs.
 * @base_id: The file name that will be written to @bs as the new
 * backing file if the job completes.  Ignored if @base is %NULL.
 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
 * @on_error: The action to take upon error.
 * @cb: Completion function for the job.
 * @opaque: Opaque pointer value passed to @cb.
 * @errp: Error object.
 *
 * Start a streaming operation on @bs.  Clusters that are unallocated
 * in @bs, but allocated in any image between @base and @bs (both
 * exclusive) will be written to @bs.  At the end of a successful
 * streaming job, the backing file of @bs will be changed to
 * @base_id in the written image and to @base in the live BlockDriverState.
 */
void stream_start(BlockDriverState *bs, BlockDriverState *base,
                  const char *base_id, int64_t speed, BlockdevOnError on_error,
                  BlockDriverCompletionFunc *cb,
                  void *opaque, Error **errp);

/**
 * commit_start:
 * @bs: Top Block device
 * @base: Block device that will be written into, and become the new top
 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
 * @on_error: The action to take upon error.
 * @cb: Completion function for the job.
 * @opaque: Opaque pointer value passed to @cb.
 * @errp: Error object.
 *
 */
void commit_start(BlockDriverState *bs, BlockDriverState *base,
                 BlockDriverState *top, int64_t speed,
                 BlockdevOnError on_error, BlockDriverCompletionFunc *cb,
                 void *opaque, Error **errp);

/*
 * mirror_start:
 * @bs: Block device to operate on.
 * @target: Block device to write to.
 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
 * @granularity: The chosen granularity for the dirty bitmap.
 * @buf_size: The amount of data that can be in flight at one time.
 * @mode: Whether to collapse all images in the chain to the target.
 * @on_source_error: The action to take upon error reading from the source.
 * @on_target_error: The action to take upon error writing to the target.
 * @cb: Completion function for the job.
 * @opaque: Opaque pointer value passed to @cb.
 * @errp: Error object.
 *
 * Start a mirroring operation on @bs.  Clusters that are allocated
 * in @bs will be written to @bs until the job is cancelled or
 * manually completed.  At the end of a successful mirroring job,
 * @bs will be switched to read from @target.
 */
void mirror_start(BlockDriverState *bs, BlockDriverState *target,
                  int64_t speed, int64_t granularity, int64_t buf_size,
                  MirrorSyncMode mode, BlockdevOnError on_source_error,
                  BlockdevOnError on_target_error,
                  BlockDriverCompletionFunc *cb,
                  void *opaque, Error **errp);

/*
 * backup_start:
 * @bs: Block device to operate on.
 * @target: Block device to write to.
 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
 * @sync_mode: What parts of the disk image should be copied to the destination.
 * @on_source_error: The action to take upon error reading from the source.
 * @on_target_error: The action to take upon error writing to the target.
 * @cb: Completion function for the job.
 * @opaque: Opaque pointer value passed to @cb.
 *
 * Start a backup operation on @bs.  Clusters in @bs are written to @target
 * until the job is cancelled or manually completed.
 */
void backup_start(BlockDriverState *bs, BlockDriverState *target,
                  int64_t speed, MirrorSyncMode sync_mode,
                  BlockdevOnError on_source_error,
                  BlockdevOnError on_target_error,
                  BlockDriverCompletionFunc *cb, void *opaque,
                  Error **errp);

#endif /* BLOCK_INT_H */