xref: /openbmc/qemu/include/block/block.h (revision ac1d8878)
1 #ifndef BLOCK_H
2 #define BLOCK_H
3 
4 #include "block/aio.h"
5 #include "qemu-common.h"
6 #include "qemu/option.h"
7 #include "qemu/coroutine.h"
8 #include "block/accounting.h"
9 #include "qapi/qmp/qobject.h"
10 #include "qapi-types.h"
11 
12 /* block.c */
13 typedef struct BlockDriver BlockDriver;
14 typedef struct BlockJob BlockJob;
15 typedef struct BdrvChild BdrvChild;
16 typedef struct BdrvChildRole BdrvChildRole;
17 typedef struct BlockJobTxn BlockJobTxn;
18 
19 typedef struct BlockDriverInfo {
20     /* in bytes, 0 if irrelevant */
21     int cluster_size;
22     /* offset at which the VM state can be saved (0 if not possible) */
23     int64_t vm_state_offset;
24     bool is_dirty;
25     /*
26      * True if unallocated blocks read back as zeroes. This is equivalent
27      * to the LBPRZ flag in the SCSI logical block provisioning page.
28      */
29     bool unallocated_blocks_are_zero;
30     /*
31      * True if the driver can optimize writing zeroes by unmapping
32      * sectors. This is equivalent to the BLKDISCARDZEROES ioctl in Linux
33      * with the difference that in qemu a discard is allowed to silently
34      * fail. Therefore we have to use bdrv_write_zeroes with the
35      * BDRV_REQ_MAY_UNMAP flag for an optimized zero write with unmapping.
36      * After this call the driver has to guarantee that the contents read
37      * back as zero. It is additionally required that the block device is
38      * opened with BDRV_O_UNMAP flag for this to work.
39      */
40     bool can_write_zeroes_with_unmap;
41     /*
42      * True if this block driver only supports compressed writes
43      */
44     bool needs_compressed_writes;
45 } BlockDriverInfo;
46 
47 typedef struct BlockFragInfo {
48     uint64_t allocated_clusters;
49     uint64_t total_clusters;
50     uint64_t fragmented_clusters;
51     uint64_t compressed_clusters;
52 } BlockFragInfo;
53 
54 typedef enum {
55     BDRV_REQ_COPY_ON_READ       = 0x1,
56     BDRV_REQ_ZERO_WRITE         = 0x2,
57     /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver
58      * is allowed to optimize a write zeroes request by unmapping (discarding)
59      * blocks if it is guaranteed that the result will read back as
60      * zeroes. The flag is only passed to the driver if the block device is
61      * opened with BDRV_O_UNMAP.
62      */
63     BDRV_REQ_MAY_UNMAP          = 0x4,
64     BDRV_REQ_NO_SERIALISING     = 0x8,
65 } BdrvRequestFlags;
66 
67 typedef struct BlockSizes {
68     uint32_t phys;
69     uint32_t log;
70 } BlockSizes;
71 
72 typedef struct HDGeometry {
73     uint32_t heads;
74     uint32_t sectors;
75     uint32_t cylinders;
76 } HDGeometry;
77 
78 #define BDRV_O_RDWR        0x0002
79 #define BDRV_O_SNAPSHOT    0x0008 /* open the file read only and save writes in a snapshot */
80 #define BDRV_O_TEMPORARY   0x0010 /* delete the file after use */
81 #define BDRV_O_NOCACHE     0x0020 /* do not use the host page cache */
82 #define BDRV_O_CACHE_WB    0x0040 /* use write-back caching */
83 #define BDRV_O_NATIVE_AIO  0x0080 /* use native AIO instead of the thread pool */
84 #define BDRV_O_NO_BACKING  0x0100 /* don't open the backing file */
85 #define BDRV_O_NO_FLUSH    0x0200 /* disable flushing on this disk */
86 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
87 #define BDRV_O_INCOMING    0x0800  /* consistency hint for incoming migration */
88 #define BDRV_O_CHECK       0x1000  /* open solely for consistency check */
89 #define BDRV_O_ALLOW_RDWR  0x2000  /* allow reopen to change from r/o to r/w */
90 #define BDRV_O_UNMAP       0x4000  /* execute guest UNMAP/TRIM operations */
91 #define BDRV_O_PROTOCOL    0x8000  /* if no block driver is explicitly given:
92                                       select an appropriate protocol driver,
93                                       ignoring the format layer */
94 
95 #define BDRV_O_CACHE_MASK  (BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH)
96 
97 
98 /* Option names of options parsed by the block layer */
99 
100 #define BDRV_OPT_CACHE_WB       "cache.writeback"
101 #define BDRV_OPT_CACHE_DIRECT   "cache.direct"
102 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush"
103 
104 
105 #define BDRV_SECTOR_BITS   9
106 #define BDRV_SECTOR_SIZE   (1ULL << BDRV_SECTOR_BITS)
107 #define BDRV_SECTOR_MASK   ~(BDRV_SECTOR_SIZE - 1)
108 
109 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \
110                                      INT_MAX >> BDRV_SECTOR_BITS)
111 
112 /*
113  * Allocation status flags
114  * BDRV_BLOCK_DATA: data is read from bs->file or another file
115  * BDRV_BLOCK_ZERO: sectors read as zero
116  * BDRV_BLOCK_OFFSET_VALID: sector stored in bs->file as raw data
117  * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
118  *                       layer (as opposed to the backing file)
119  * BDRV_BLOCK_RAW: used internally to indicate that the request
120  *                 was answered by the raw driver and that one
121  *                 should look in bs->file directly.
122  *
123  * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 represent the offset in
124  * bs->file where sector data can be read from as raw data.
125  *
126  * DATA == 0 && ZERO == 0 means that data is read from backing_hd if present.
127  *
128  * DATA ZERO OFFSET_VALID
129  *  t    t        t       sectors read as zero, bs->file is zero at offset
130  *  t    f        t       sectors read as valid from bs->file at offset
131  *  f    t        t       sectors preallocated, read as zero, bs->file not
132  *                        necessarily zero at offset
133  *  f    f        t       sectors preallocated but read from backing_hd,
134  *                        bs->file contains garbage at offset
135  *  t    t        f       sectors preallocated, read as zero, unknown offset
136  *  t    f        f       sectors read from unknown file or offset
137  *  f    t        f       not allocated or unknown offset, read as zero
138  *  f    f        f       not allocated or unknown offset, read from backing_hd
139  */
140 #define BDRV_BLOCK_DATA         0x01
141 #define BDRV_BLOCK_ZERO         0x02
142 #define BDRV_BLOCK_OFFSET_VALID 0x04
143 #define BDRV_BLOCK_RAW          0x08
144 #define BDRV_BLOCK_ALLOCATED    0x10
145 #define BDRV_BLOCK_OFFSET_MASK  BDRV_SECTOR_MASK
146 
147 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue;
148 
149 typedef struct BDRVReopenState {
150     BlockDriverState *bs;
151     int flags;
152     QDict *options;
153     void *opaque;
154 } BDRVReopenState;
155 
156 /*
157  * Block operation types
158  */
159 typedef enum BlockOpType {
160     BLOCK_OP_TYPE_BACKUP_SOURCE,
161     BLOCK_OP_TYPE_BACKUP_TARGET,
162     BLOCK_OP_TYPE_CHANGE,
163     BLOCK_OP_TYPE_COMMIT_SOURCE,
164     BLOCK_OP_TYPE_COMMIT_TARGET,
165     BLOCK_OP_TYPE_DATAPLANE,
166     BLOCK_OP_TYPE_DRIVE_DEL,
167     BLOCK_OP_TYPE_EJECT,
168     BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
169     BLOCK_OP_TYPE_INTERNAL_SNAPSHOT,
170     BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE,
171     BLOCK_OP_TYPE_MIRROR,
172     BLOCK_OP_TYPE_RESIZE,
173     BLOCK_OP_TYPE_STREAM,
174     BLOCK_OP_TYPE_REPLACE,
175     BLOCK_OP_TYPE_MAX,
176 } BlockOpType;
177 
178 void bdrv_info_print(Monitor *mon, const QObject *data);
179 void bdrv_info(Monitor *mon, QObject **ret_data);
180 void bdrv_stats_print(Monitor *mon, const QObject *data);
181 void bdrv_info_stats(Monitor *mon, QObject **ret_data);
182 
183 /* disk I/O throttling */
184 void bdrv_io_limits_enable(BlockDriverState *bs, const char *group);
185 void bdrv_io_limits_disable(BlockDriverState *bs);
186 void bdrv_io_limits_update_group(BlockDriverState *bs, const char *group);
187 
188 void bdrv_init(void);
189 void bdrv_init_with_whitelist(void);
190 BlockDriver *bdrv_find_protocol(const char *filename,
191                                 bool allow_protocol_prefix,
192                                 Error **errp);
193 BlockDriver *bdrv_find_format(const char *format_name);
194 int bdrv_create(BlockDriver *drv, const char* filename,
195                 QemuOpts *opts, Error **errp);
196 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp);
197 BlockDriverState *bdrv_new_root(void);
198 BlockDriverState *bdrv_new(void);
199 void bdrv_make_anon(BlockDriverState *bs);
200 void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old);
201 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top);
202 void bdrv_replace_in_backing_chain(BlockDriverState *old,
203                                    BlockDriverState *new);
204 
205 int bdrv_parse_cache_flags(const char *mode, int *flags);
206 int bdrv_parse_discard_flags(const char *mode, int *flags);
207 BdrvChild *bdrv_open_child(const char *filename,
208                            QDict *options, const char *bdref_key,
209                            BlockDriverState* parent,
210                            const BdrvChildRole *child_role,
211                            bool allow_none, Error **errp);
212 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd);
213 int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp);
214 int bdrv_append_temp_snapshot(BlockDriverState *bs, int flags, Error **errp);
215 int bdrv_open(BlockDriverState **pbs, const char *filename,
216               const char *reference, QDict *options, int flags, Error **errp);
217 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
218                                     BlockDriverState *bs,
219                                     QDict *options, int flags);
220 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp);
221 int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp);
222 int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
223                         BlockReopenQueue *queue, Error **errp);
224 void bdrv_reopen_commit(BDRVReopenState *reopen_state);
225 void bdrv_reopen_abort(BDRVReopenState *reopen_state);
226 void bdrv_close(BlockDriverState *bs);
227 void bdrv_add_close_notifier(BlockDriverState *bs, Notifier *notify);
228 int bdrv_read(BlockDriverState *bs, int64_t sector_num,
229               uint8_t *buf, int nb_sectors);
230 int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
231                           uint8_t *buf, int nb_sectors);
232 int bdrv_write(BlockDriverState *bs, int64_t sector_num,
233                const uint8_t *buf, int nb_sectors);
234 int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num,
235                int nb_sectors, BdrvRequestFlags flags);
236 BlockAIOCB *bdrv_aio_write_zeroes(BlockDriverState *bs, int64_t sector_num,
237                                   int nb_sectors, BdrvRequestFlags flags,
238                                   BlockCompletionFunc *cb, void *opaque);
239 int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags);
240 int bdrv_pread(BlockDriverState *bs, int64_t offset,
241                void *buf, int count);
242 int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
243                 const void *buf, int count);
244 int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov);
245 int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
246     const void *buf, int count);
247 int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num,
248     int nb_sectors, QEMUIOVector *qiov);
249 int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
250     int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
251 int coroutine_fn bdrv_co_readv_no_serialising(BlockDriverState *bs,
252     int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
253 int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,
254     int nb_sectors, QEMUIOVector *qiov);
255 /*
256  * Efficiently zero a region of the disk image.  Note that this is a regular
257  * I/O request like read or write and should have a reasonable size.  This
258  * function is not suitable for zeroing the entire image in a single request
259  * because it may allocate memory for the entire region.
260  */
261 int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
262     int nb_sectors, BdrvRequestFlags flags);
263 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
264     const char *backing_file);
265 int bdrv_get_backing_file_depth(BlockDriverState *bs);
266 void bdrv_refresh_filename(BlockDriverState *bs);
267 int bdrv_truncate(BlockDriverState *bs, int64_t offset);
268 int64_t bdrv_nb_sectors(BlockDriverState *bs);
269 int64_t bdrv_getlength(BlockDriverState *bs);
270 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs);
271 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
272 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp);
273 int bdrv_commit(BlockDriverState *bs);
274 int bdrv_commit_all(void);
275 int bdrv_change_backing_file(BlockDriverState *bs,
276     const char *backing_file, const char *backing_fmt);
277 void bdrv_register(BlockDriver *bdrv);
278 int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
279                            BlockDriverState *base,
280                            const char *backing_file_str);
281 BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
282                                     BlockDriverState *bs);
283 BlockDriverState *bdrv_find_base(BlockDriverState *bs);
284 
285 
286 typedef struct BdrvCheckResult {
287     int corruptions;
288     int leaks;
289     int check_errors;
290     int corruptions_fixed;
291     int leaks_fixed;
292     int64_t image_end_offset;
293     BlockFragInfo bfi;
294 } BdrvCheckResult;
295 
296 typedef enum {
297     BDRV_FIX_LEAKS    = 1,
298     BDRV_FIX_ERRORS   = 2,
299 } BdrvCheckMode;
300 
301 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
302 
303 /* The units of offset and total_work_size may be chosen arbitrarily by the
304  * block driver; total_work_size may change during the course of the amendment
305  * operation */
306 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset,
307                                       int64_t total_work_size);
308 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts,
309                        BlockDriverAmendStatusCB *status_cb);
310 
311 /* external snapshots */
312 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,
313                                       BlockDriverState *candidate);
314 bool bdrv_is_first_non_filter(BlockDriverState *candidate);
315 
316 /* check if a named node can be replaced when doing drive-mirror */
317 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs,
318                                         const char *node_name, Error **errp);
319 
320 /* async block I/O */
321 typedef void BlockDriverDirtyHandler(BlockDriverState *bs, int64_t sector,
322                                      int sector_num);
323 BlockAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
324                            QEMUIOVector *iov, int nb_sectors,
325                            BlockCompletionFunc *cb, void *opaque);
326 BlockAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
327                             QEMUIOVector *iov, int nb_sectors,
328                             BlockCompletionFunc *cb, void *opaque);
329 BlockAIOCB *bdrv_aio_flush(BlockDriverState *bs,
330                            BlockCompletionFunc *cb, void *opaque);
331 BlockAIOCB *bdrv_aio_discard(BlockDriverState *bs,
332                              int64_t sector_num, int nb_sectors,
333                              BlockCompletionFunc *cb, void *opaque);
334 void bdrv_aio_cancel(BlockAIOCB *acb);
335 void bdrv_aio_cancel_async(BlockAIOCB *acb);
336 
337 typedef struct BlockRequest {
338     /* Fields to be filled by multiwrite caller */
339     union {
340         struct {
341             int64_t sector;
342             int nb_sectors;
343             int flags;
344             QEMUIOVector *qiov;
345         };
346         struct {
347             int req;
348             void *buf;
349         };
350     };
351     BlockCompletionFunc *cb;
352     void *opaque;
353 
354     /* Filled by multiwrite implementation */
355     int error;
356 } BlockRequest;
357 
358 int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs,
359     int num_reqs);
360 
361 /* sg packet commands */
362 int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf);
363 BlockAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
364         unsigned long int req, void *buf,
365         BlockCompletionFunc *cb, void *opaque);
366 
367 /* Invalidate any cached metadata used by image formats */
368 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
369 void bdrv_invalidate_cache_all(Error **errp);
370 
371 /* Ensure contents are flushed to disk.  */
372 int bdrv_flush(BlockDriverState *bs);
373 int coroutine_fn bdrv_co_flush(BlockDriverState *bs);
374 int bdrv_flush_all(void);
375 void bdrv_close_all(void);
376 void bdrv_drain(BlockDriverState *bs);
377 void bdrv_drain_all(void);
378 
379 int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
380 int bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
381 int bdrv_has_zero_init_1(BlockDriverState *bs);
382 int bdrv_has_zero_init(BlockDriverState *bs);
383 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs);
384 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs);
385 int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num,
386                               int nb_sectors, int *pnum);
387 int64_t bdrv_get_block_status_above(BlockDriverState *bs,
388                                     BlockDriverState *base,
389                                     int64_t sector_num,
390                                     int nb_sectors, int *pnum);
391 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
392                       int *pnum);
393 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,
394                             int64_t sector_num, int nb_sectors, int *pnum);
395 
396 int bdrv_is_read_only(BlockDriverState *bs);
397 int bdrv_is_sg(BlockDriverState *bs);
398 int bdrv_enable_write_cache(BlockDriverState *bs);
399 void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce);
400 bool bdrv_is_inserted(BlockDriverState *bs);
401 int bdrv_media_changed(BlockDriverState *bs);
402 void bdrv_lock_medium(BlockDriverState *bs, bool locked);
403 void bdrv_eject(BlockDriverState *bs, bool eject_flag);
404 const char *bdrv_get_format_name(BlockDriverState *bs);
405 BlockDriverState *bdrv_find_node(const char *node_name);
406 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp);
407 BlockDriverState *bdrv_lookup_bs(const char *device,
408                                  const char *node_name,
409                                  Error **errp);
410 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base);
411 BlockDriverState *bdrv_next_node(BlockDriverState *bs);
412 BlockDriverState *bdrv_next(BlockDriverState *bs);
413 int bdrv_is_encrypted(BlockDriverState *bs);
414 int bdrv_key_required(BlockDriverState *bs);
415 int bdrv_set_key(BlockDriverState *bs, const char *key);
416 void bdrv_add_key(BlockDriverState *bs, const char *key, Error **errp);
417 int bdrv_query_missing_keys(void);
418 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
419                          void *opaque);
420 const char *bdrv_get_node_name(const BlockDriverState *bs);
421 const char *bdrv_get_device_name(const BlockDriverState *bs);
422 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs);
423 int bdrv_get_flags(BlockDriverState *bs);
424 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
425                           const uint8_t *buf, int nb_sectors);
426 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi);
427 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs);
428 void bdrv_round_to_clusters(BlockDriverState *bs,
429                             int64_t sector_num, int nb_sectors,
430                             int64_t *cluster_sector_num,
431                             int *cluster_nb_sectors);
432 
433 const char *bdrv_get_encrypted_filename(BlockDriverState *bs);
434 void bdrv_get_backing_filename(BlockDriverState *bs,
435                                char *filename, int filename_size);
436 void bdrv_get_full_backing_filename(BlockDriverState *bs,
437                                     char *dest, size_t sz, Error **errp);
438 void bdrv_get_full_backing_filename_from_filename(const char *backed,
439                                                   const char *backing,
440                                                   char *dest, size_t sz,
441                                                   Error **errp);
442 int bdrv_is_snapshot(BlockDriverState *bs);
443 
444 int path_has_protocol(const char *path);
445 int path_is_absolute(const char *path);
446 void path_combine(char *dest, int dest_size,
447                   const char *base_path,
448                   const char *filename);
449 
450 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
451 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
452                       int64_t pos, int size);
453 
454 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
455                       int64_t pos, int size);
456 
457 void bdrv_img_create(const char *filename, const char *fmt,
458                      const char *base_filename, const char *base_fmt,
459                      char *options, uint64_t img_size, int flags,
460                      Error **errp, bool quiet);
461 
462 /* Returns the alignment in bytes that is required so that no bounce buffer
463  * is required throughout the stack */
464 size_t bdrv_min_mem_align(BlockDriverState *bs);
465 /* Returns optimal alignment in bytes for bounce buffer */
466 size_t bdrv_opt_mem_align(BlockDriverState *bs);
467 void *qemu_blockalign(BlockDriverState *bs, size_t size);
468 void *qemu_blockalign0(BlockDriverState *bs, size_t size);
469 void *qemu_try_blockalign(BlockDriverState *bs, size_t size);
470 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size);
471 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);
472 
473 struct HBitmapIter;
474 typedef struct BdrvDirtyBitmap BdrvDirtyBitmap;
475 BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
476                                           uint32_t granularity,
477                                           const char *name,
478                                           Error **errp);
479 int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs,
480                                        BdrvDirtyBitmap *bitmap,
481                                        Error **errp);
482 BdrvDirtyBitmap *bdrv_dirty_bitmap_abdicate(BlockDriverState *bs,
483                                             BdrvDirtyBitmap *bitmap,
484                                             Error **errp);
485 BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
486                                            BdrvDirtyBitmap *bitmap,
487                                            Error **errp);
488 BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
489                                         const char *name);
490 void bdrv_dirty_bitmap_make_anon(BdrvDirtyBitmap *bitmap);
491 void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
492 void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
493 void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
494 BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
495 uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
496 uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap);
497 bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
498 bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap);
499 DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap);
500 int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
501 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
502                            int64_t cur_sector, int nr_sectors);
503 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
504                              int64_t cur_sector, int nr_sectors);
505 void bdrv_dirty_iter_init(BdrvDirtyBitmap *bitmap, struct HBitmapIter *hbi);
506 void bdrv_set_dirty_iter(struct HBitmapIter *hbi, int64_t offset);
507 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap);
508 
509 void bdrv_enable_copy_on_read(BlockDriverState *bs);
510 void bdrv_disable_copy_on_read(BlockDriverState *bs);
511 
512 void bdrv_ref(BlockDriverState *bs);
513 void bdrv_unref(BlockDriverState *bs);
514 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child);
515 
516 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
517 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
518 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason);
519 void bdrv_op_block_all(BlockDriverState *bs, Error *reason);
520 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason);
521 bool bdrv_op_blocker_is_empty(BlockDriverState *bs);
522 
523 #define BLKDBG_EVENT(child, evt) \
524     do { \
525         if (child) { \
526             bdrv_debug_event(child->bs, evt); \
527         } \
528     } while (0)
529 
530 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event);
531 
532 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
533                            const char *tag);
534 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag);
535 int bdrv_debug_resume(BlockDriverState *bs, const char *tag);
536 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag);
537 
538 /**
539  * bdrv_get_aio_context:
540  *
541  * Returns: the currently bound #AioContext
542  */
543 AioContext *bdrv_get_aio_context(BlockDriverState *bs);
544 
545 /**
546  * bdrv_set_aio_context:
547  *
548  * Changes the #AioContext used for fd handlers, timers, and BHs by this
549  * BlockDriverState and all its children.
550  *
551  * This function must be called with iothread lock held.
552  */
553 void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context);
554 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz);
555 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo);
556 
557 void bdrv_io_plug(BlockDriverState *bs);
558 void bdrv_io_unplug(BlockDriverState *bs);
559 void bdrv_flush_io_queue(BlockDriverState *bs);
560 
561 /**
562  * bdrv_drained_begin:
563  *
564  * Begin a quiesced section for exclusive access to the BDS, by disabling
565  * external request sources including NBD server and device model. Note that
566  * this doesn't block timers or coroutines from submitting more requests, which
567  * means block_job_pause is still necessary.
568  *
569  * This function can be recursive.
570  */
571 void bdrv_drained_begin(BlockDriverState *bs);
572 
573 /**
574  * bdrv_drained_end:
575  *
576  * End a quiescent section started by bdrv_drained_begin().
577  */
578 void bdrv_drained_end(BlockDriverState *bs);
579 
580 #endif
581