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/accounting.h"
28#include "block/block.h"
29#include "block/aio-wait.h"
30#include "qemu/queue.h"
31#include "qemu/coroutine.h"
32#include "qemu/stats64.h"
33#include "qemu/timer.h"
34#include "qemu/hbitmap.h"
35#include "block/snapshot.h"
36#include "qemu/throttle.h"
37
38#define BLOCK_FLAG_LAZY_REFCOUNTS 8
39
40#define BLOCK_OPT_SIZE "size"
41#define BLOCK_OPT_ENCRYPT "encryption"
42#define BLOCK_OPT_ENCRYPT_FORMAT "encrypt.format"
43#define BLOCK_OPT_COMPAT6 "compat6"
44#define BLOCK_OPT_HWVERSION "hwversion"
45#define BLOCK_OPT_BACKING_FILE "backing_file"
46#define BLOCK_OPT_BACKING_FMT "backing_fmt"
47#define BLOCK_OPT_CLUSTER_SIZE "cluster_size"
48#define BLOCK_OPT_TABLE_SIZE "table_size"
49#define BLOCK_OPT_PREALLOC "preallocation"
50#define BLOCK_OPT_SUBFMT "subformat"
51#define BLOCK_OPT_COMPAT_LEVEL "compat"
52#define BLOCK_OPT_LAZY_REFCOUNTS "lazy_refcounts"
53#define BLOCK_OPT_ADAPTER_TYPE "adapter_type"
54#define BLOCK_OPT_REDUNDANCY "redundancy"
55#define BLOCK_OPT_NOCOW "nocow"
56#define BLOCK_OPT_OBJECT_SIZE "object_size"
57#define BLOCK_OPT_REFCOUNT_BITS "refcount_bits"
58#define BLOCK_OPT_DATA_FILE "data_file"
59#define BLOCK_OPT_DATA_FILE_RAW "data_file_raw"
60
61#define BLOCK_PROBE_BUF_SIZE 512
62
63enum BdrvTrackedRequestType {
64 BDRV_TRACKED_READ,
65 BDRV_TRACKED_WRITE,
66 BDRV_TRACKED_DISCARD,
67 BDRV_TRACKED_TRUNCATE,
68};
69
70typedef struct BdrvTrackedRequest {
71 BlockDriverState *bs;
72 int64_t offset;
73 uint64_t bytes;
74 enum BdrvTrackedRequestType type;
75
76 bool serialising;
77 int64_t overlap_offset;
78 uint64_t overlap_bytes;
79
80 QLIST_ENTRY(BdrvTrackedRequest) list;
81 Coroutine *co; /* owner, used for deadlock detection */
82 CoQueue wait_queue; /* coroutines blocked on this request */
83
84 struct BdrvTrackedRequest *waiting_for;
85} BdrvTrackedRequest;
86
87struct BlockDriver {
88 const char *format_name;
89 int instance_size;
90
91 /* set to true if the BlockDriver is a block filter. Block filters pass
92 * certain callbacks that refer to data (see block.c) to their bs->file if
93 * the driver doesn't implement them. Drivers that do not wish to forward
94 * must implement them and return -ENOTSUP.
95 */
96 bool is_filter;
97 /* for snapshots block filter like Quorum can implement the
98 * following recursive callback.
99 * It's purpose is to recurse on the filter children while calling
100 * bdrv_recurse_is_first_non_filter on them.
101 * For a sample implementation look in the future Quorum block filter.
102 */
103 bool (*bdrv_recurse_is_first_non_filter)(BlockDriverState *bs,
104 BlockDriverState *candidate);
105
106 int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
107 int (*bdrv_probe_device)(const char *filename);
108
109 /* Any driver implementing this callback is expected to be able to handle
110 * NULL file names in its .bdrv_open() implementation */
111 void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp);
112 /* Drivers not implementing bdrv_parse_filename nor bdrv_open should have
113 * this field set to true, except ones that are defined only by their
114 * child's bs.
115 * An example of the last type will be the quorum block driver.
116 */
117 bool bdrv_needs_filename;
118
119 /* Set if a driver can support backing files */
120 bool supports_backing;
121
122 /* For handling image reopen for split or non-split files */
123 int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state,
124 BlockReopenQueue *queue, Error **errp);
125 void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state);
126 void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state);
127 void (*bdrv_join_options)(QDict *options, QDict *old_options);
128
129 int (*bdrv_open)(BlockDriverState *bs, QDict *options, int flags,
130 Error **errp);
131
132 /* Protocol drivers should implement this instead of bdrv_open */
133 int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags,
134 Error **errp);
135 void (*bdrv_close)(BlockDriverState *bs);
136 int coroutine_fn (*bdrv_co_create)(BlockdevCreateOptions *opts,
137 Error **errp);
138 int coroutine_fn (*bdrv_co_create_opts)(const char *filename,
139 QemuOpts *opts,
140 Error **errp);
141 int (*bdrv_make_empty)(BlockDriverState *bs);
142
143 /*
144 * Refreshes the bs->exact_filename field. If that is impossible,
145 * bs->exact_filename has to be left empty.
146 */
147 void (*bdrv_refresh_filename)(BlockDriverState *bs);
148
149 /*
150 * Gathers the open options for all children into @target.
151 * A simple format driver (without backing file support) might
152 * implement this function like this:
153 *
154 * QINCREF(bs->file->bs->full_open_options);
155 * qdict_put(target, "file", bs->file->bs->full_open_options);
156 *
157 * If not specified, the generic implementation will simply put
158 * all children's options under their respective name.
159 *
160 * @backing_overridden is true when bs->backing seems not to be
161 * the child that would result from opening bs->backing_file.
162 * Therefore, if it is true, the backing child's options should be
163 * gathered; otherwise, there is no need since the backing child
164 * is the one implied by the image header.
165 *
166 * Note that ideally this function would not be needed. Every
167 * block driver which implements it is probably doing something
168 * shady regarding its runtime option structure.
169 */
170 void (*bdrv_gather_child_options)(BlockDriverState *bs, QDict *target,
171 bool backing_overridden);
172
173 /*
174 * Returns an allocated string which is the directory name of this BDS: It
175 * will be used to make relative filenames absolute by prepending this
176 * function's return value to them.
177 */
178 char *(*bdrv_dirname)(BlockDriverState *bs, Error **errp);
179
180 /* aio */
181 BlockAIOCB *(*bdrv_aio_preadv)(BlockDriverState *bs,
182 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags,
183 BlockCompletionFunc *cb, void *opaque);
184 BlockAIOCB *(*bdrv_aio_pwritev)(BlockDriverState *bs,
185 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags,
186 BlockCompletionFunc *cb, void *opaque);
187 BlockAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
188 BlockCompletionFunc *cb, void *opaque);
189 BlockAIOCB *(*bdrv_aio_pdiscard)(BlockDriverState *bs,
190 int64_t offset, int bytes,
191 BlockCompletionFunc *cb, void *opaque);
192
193 int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs,
194 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
195
196 /**
197 * @offset: position in bytes to read at
198 * @bytes: number of bytes to read
199 * @qiov: the buffers to fill with read data
200 * @flags: currently unused, always 0
201 *
202 * @offset and @bytes will be a multiple of 'request_alignment',
203 * but the length of individual @qiov elements does not have to
204 * be a multiple.
205 *
206 * @bytes will always equal the total size of @qiov, and will be
207 * no larger than 'max_transfer'.
208 *
209 * The buffer in @qiov may point directly to guest memory.
210 */
211 int coroutine_fn (*bdrv_co_preadv)(BlockDriverState *bs,
212 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags);
213 int coroutine_fn (*bdrv_co_preadv_part)(BlockDriverState *bs,
214 uint64_t offset, uint64_t bytes,
215 QEMUIOVector *qiov, size_t qiov_offset, int flags);
216 int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs,
217 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, int flags);
218 /**
219 * @offset: position in bytes to write at
220 * @bytes: number of bytes to write
221 * @qiov: the buffers containing data to write
222 * @flags: zero or more bits allowed by 'supported_write_flags'
223 *
224 * @offset and @bytes will be a multiple of 'request_alignment',
225 * but the length of individual @qiov elements does not have to
226 * be a multiple.
227 *
228 * @bytes will always equal the total size of @qiov, and will be
229 * no larger than 'max_transfer'.
230 *
231 * The buffer in @qiov may point directly to guest memory.
232 */
233 int coroutine_fn (*bdrv_co_pwritev)(BlockDriverState *bs,
234 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags);
235 int coroutine_fn (*bdrv_co_pwritev_part)(BlockDriverState *bs,
236 uint64_t offset, uint64_t bytes,
237 QEMUIOVector *qiov, size_t qiov_offset, int flags);
238
239 /*
240 * Efficiently zero a region of the disk image. Typically an image format
241 * would use a compact metadata representation to implement this. This
242 * function pointer may be NULL or return -ENOSUP and .bdrv_co_writev()
243 * will be called instead.
244 */
245 int coroutine_fn (*bdrv_co_pwrite_zeroes)(BlockDriverState *bs,
246 int64_t offset, int bytes, BdrvRequestFlags flags);
247 int coroutine_fn (*bdrv_co_pdiscard)(BlockDriverState *bs,
248 int64_t offset, int bytes);
249
250 /* Map [offset, offset + nbytes) range onto a child of @bs to copy from,
251 * and invoke bdrv_co_copy_range_from(child, ...), or invoke
252 * bdrv_co_copy_range_to() if @bs is the leaf child to copy data from.
253 *
254 * See the comment of bdrv_co_copy_range for the parameter and return value
255 * semantics.
256 */
257 int coroutine_fn (*bdrv_co_copy_range_from)(BlockDriverState *bs,
258 BdrvChild *src,
259 uint64_t offset,
260 BdrvChild *dst,
261 uint64_t dst_offset,
262 uint64_t bytes,
263 BdrvRequestFlags read_flags,
264 BdrvRequestFlags write_flags);
265
266 /* Map [offset, offset + nbytes) range onto a child of bs to copy data to,
267 * and invoke bdrv_co_copy_range_to(child, src, ...), or perform the copy
268 * operation if @bs is the leaf and @src has the same BlockDriver. Return
269 * -ENOTSUP if @bs is the leaf but @src has a different BlockDriver.
270 *
271 * See the comment of bdrv_co_copy_range for the parameter and return value
272 * semantics.
273 */
274 int coroutine_fn (*bdrv_co_copy_range_to)(BlockDriverState *bs,
275 BdrvChild *src,
276 uint64_t src_offset,
277 BdrvChild *dst,
278 uint64_t dst_offset,
279 uint64_t bytes,
280 BdrvRequestFlags read_flags,
281 BdrvRequestFlags write_flags);
282
283 /*
284 * Building block for bdrv_block_status[_above] and
285 * bdrv_is_allocated[_above]. The driver should answer only
286 * according to the current layer, and should only need to set
287 * BDRV_BLOCK_DATA, BDRV_BLOCK_ZERO, BDRV_BLOCK_OFFSET_VALID,
288 * and/or BDRV_BLOCK_RAW; if the current layer defers to a backing
289 * layer, the result should be 0 (and not BDRV_BLOCK_ZERO). See
290 * block.h for the overall meaning of the bits. As a hint, the
291 * flag want_zero is true if the caller cares more about precise
292 * mappings (favor accurate _OFFSET_VALID/_ZERO) or false for
293 * overall allocation (favor larger *pnum, perhaps by reporting
294 * _DATA instead of _ZERO). The block layer guarantees input
295 * clamped to bdrv_getlength() and aligned to request_alignment,
296 * as well as non-NULL pnum, map, and file; in turn, the driver
297 * must return an error or set pnum to an aligned non-zero value.
298 */
299 int coroutine_fn (*bdrv_co_block_status)(BlockDriverState *bs,
300 bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum,
301 int64_t *map, BlockDriverState **file);
302
303 /*
304 * Invalidate any cached meta-data.
305 */
306 void coroutine_fn (*bdrv_co_invalidate_cache)(BlockDriverState *bs,
307 Error **errp);
308 int (*bdrv_inactivate)(BlockDriverState *bs);
309
310 /*
311 * Flushes all data for all layers by calling bdrv_co_flush for underlying
312 * layers, if needed. This function is needed for deterministic
313 * synchronization of the flush finishing callback.
314 */
315 int coroutine_fn (*bdrv_co_flush)(BlockDriverState *bs);
316
317 /*
318 * Flushes all data that was already written to the OS all the way down to
319 * the disk (for example file-posix.c calls fsync()).
320 */
321 int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs);
322
323 /*
324 * Flushes all internal caches to the OS. The data may still sit in a
325 * writeback cache of the host OS, but it will survive a crash of the qemu
326 * process.
327 */
328 int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs);
329
330 /*
331 * Drivers setting this field must be able to work with just a plain
332 * filename with '<protocol_name>:' as a prefix, and no other options.
333 * Options may be extracted from the filename by implementing
334 * bdrv_parse_filename.
335 */
336 const char *protocol_name;
337 int coroutine_fn (*bdrv_co_truncate)(BlockDriverState *bs, int64_t offset,
338 PreallocMode prealloc, Error **errp);
339
340 int64_t (*bdrv_getlength)(BlockDriverState *bs);
341 bool has_variable_length;
342 int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs);
343 BlockMeasureInfo *(*bdrv_measure)(QemuOpts *opts, BlockDriverState *in_bs,
344 Error **errp);
345
346 int coroutine_fn (*bdrv_co_pwritev_compressed)(BlockDriverState *bs,
347 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov);
348 int coroutine_fn (*bdrv_co_pwritev_compressed_part)(BlockDriverState *bs,
349 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov,
350 size_t qiov_offset);
351
352 int (*bdrv_snapshot_create)(BlockDriverState *bs,
353 QEMUSnapshotInfo *sn_info);
354 int (*bdrv_snapshot_goto)(BlockDriverState *bs,
355 const char *snapshot_id);
356 int (*bdrv_snapshot_delete)(BlockDriverState *bs,
357 const char *snapshot_id,
358 const char *name,
359 Error **errp);
360 int (*bdrv_snapshot_list)(BlockDriverState *bs,
361 QEMUSnapshotInfo **psn_info);
362 int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
363 const char *snapshot_id,
364 const char *name,
365 Error **errp);
366 int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
367 ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs,
368 Error **errp);
369
370 int coroutine_fn (*bdrv_save_vmstate)(BlockDriverState *bs,
371 QEMUIOVector *qiov,
372 int64_t pos);
373 int coroutine_fn (*bdrv_load_vmstate)(BlockDriverState *bs,
374 QEMUIOVector *qiov,
375 int64_t pos);
376
377 int (*bdrv_change_backing_file)(BlockDriverState *bs,
378 const char *backing_file, const char *backing_fmt);
379
380 /* removable device specific */
381 bool (*bdrv_is_inserted)(BlockDriverState *bs);
382 void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag);
383 void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked);
384
385 /* to control generic scsi devices */
386 BlockAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
387 unsigned long int req, void *buf,
388 BlockCompletionFunc *cb, void *opaque);
389 int coroutine_fn (*bdrv_co_ioctl)(BlockDriverState *bs,
390 unsigned long int req, void *buf);
391
392 /* List of options for creating images, terminated by name == NULL */
393 QemuOptsList *create_opts;
394 /*
395 * If this driver supports reopening images this contains a
396 * NULL-terminated list of the runtime options that can be
397 * modified. If an option in this list is unspecified during
398 * reopen then it _must_ be reset to its default value or return
399 * an error.
400 */
401 const char *const *mutable_opts;
402
403 /*
404 * Returns 0 for completed check, -errno for internal errors.
405 * The check results are stored in result.
406 */
407 int coroutine_fn (*bdrv_co_check)(BlockDriverState *bs,
408 BdrvCheckResult *result,
409 BdrvCheckMode fix);
410
411 int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts,
412 BlockDriverAmendStatusCB *status_cb,
413 void *cb_opaque,
414 Error **errp);
415
416 void (*bdrv_debug_event)(BlockDriverState *bs, BlkdebugEvent event);
417
418 /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */
419 int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event,
420 const char *tag);
421 int (*bdrv_debug_remove_breakpoint)(BlockDriverState *bs,
422 const char *tag);
423 int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag);
424 bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag);
425
426 void (*bdrv_refresh_limits)(BlockDriverState *bs, Error **errp);
427
428 /*
429 * Returns 1 if newly created images are guaranteed to contain only
430 * zeros, 0 otherwise.
431 * Must return 0 if .bdrv_has_zero_init_truncate() returns 0.
432 */
433 int (*bdrv_has_zero_init)(BlockDriverState *bs);
434
435 /*
436 * Returns 1 if new areas added by growing the image with
437 * PREALLOC_MODE_OFF contain only zeros, 0 otherwise.
438 */
439 int (*bdrv_has_zero_init_truncate)(BlockDriverState *bs);
440
441 /* Remove fd handlers, timers, and other event loop callbacks so the event
442 * loop is no longer in use. Called with no in-flight requests and in
443 * depth-first traversal order with parents before child nodes.
444 */
445 void (*bdrv_detach_aio_context)(BlockDriverState *bs);
446
447 /* Add fd handlers, timers, and other event loop callbacks so I/O requests
448 * can be processed again. Called with no in-flight requests and in
449 * depth-first traversal order with child nodes before parent nodes.
450 */
451 void (*bdrv_attach_aio_context)(BlockDriverState *bs,
452 AioContext *new_context);
453
454 /* io queue for linux-aio */
455 void (*bdrv_io_plug)(BlockDriverState *bs);
456 void (*bdrv_io_unplug)(BlockDriverState *bs);
457
458 /**
459 * Try to get @bs's logical and physical block size.
460 * On success, store them in @bsz and return zero.
461 * On failure, return negative errno.
462 */
463 int (*bdrv_probe_blocksizes)(BlockDriverState *bs, BlockSizes *bsz);
464 /**
465 * Try to get @bs's geometry (cyls, heads, sectors)
466 * On success, store them in @geo and return 0.
467 * On failure return -errno.
468 * Only drivers that want to override guest geometry implement this
469 * callback; see hd_geometry_guess().
470 */
471 int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo);
472
473 /**
474 * bdrv_co_drain_begin is called if implemented in the beginning of a
475 * drain operation to drain and stop any internal sources of requests in
476 * the driver.
477 * bdrv_co_drain_end is called if implemented at the end of the drain.
478 *
479 * They should be used by the driver to e.g. manage scheduled I/O
480 * requests, or toggle an internal state. After the end of the drain new
481 * requests will continue normally.
482 */
483 void coroutine_fn (*bdrv_co_drain_begin)(BlockDriverState *bs);
484 void coroutine_fn (*bdrv_co_drain_end)(BlockDriverState *bs);
485
486 void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child,
487 Error **errp);
488 void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child,
489 Error **errp);
490
491 /**
492 * Informs the block driver that a permission change is intended. The
493 * driver checks whether the change is permissible and may take other
494 * preparations for the change (e.g. get file system locks). This operation
495 * is always followed either by a call to either .bdrv_set_perm or
496 * .bdrv_abort_perm_update.
497 *
498 * Checks whether the requested set of cumulative permissions in @perm
499 * can be granted for accessing @bs and whether no other users are using
500 * permissions other than those given in @shared (both arguments take
501 * BLK_PERM_* bitmasks).
502 *
503 * If both conditions are met, 0 is returned. Otherwise, -errno is returned
504 * and errp is set to an error describing the conflict.
505 */
506 int (*bdrv_check_perm)(BlockDriverState *bs, uint64_t perm,
507 uint64_t shared, Error **errp);
508
509 /**
510 * Called to inform the driver that the set of cumulative set of used
511 * permissions for @bs has changed to @perm, and the set of sharable
512 * permission to @shared. The driver can use this to propagate changes to
513 * its children (i.e. request permissions only if a parent actually needs
514 * them).
515 *
516 * This function is only invoked after bdrv_check_perm(), so block drivers
517 * may rely on preparations made in their .bdrv_check_perm implementation.
518 */
519 void (*bdrv_set_perm)(BlockDriverState *bs, uint64_t perm, uint64_t shared);
520
521 /*
522 * Called to inform the driver that after a previous bdrv_check_perm()
523 * call, the permission update is not performed and any preparations made
524 * for it (e.g. taken file locks) need to be undone.
525 *
526 * This function can be called even for nodes that never saw a
527 * bdrv_check_perm() call. It is a no-op then.
528 */
529 void (*bdrv_abort_perm_update)(BlockDriverState *bs);
530
531 /**
532 * Returns in @nperm and @nshared the permissions that the driver for @bs
533 * needs on its child @c, based on the cumulative permissions requested by
534 * the parents in @parent_perm and @parent_shared.
535 *
536 * If @c is NULL, return the permissions for attaching a new child for the
537 * given @role.
538 *
539 * If @reopen_queue is non-NULL, don't return the currently needed
540 * permissions, but those that will be needed after applying the
541 * @reopen_queue.
542 */
543 void (*bdrv_child_perm)(BlockDriverState *bs, BdrvChild *c,
544 const BdrvChildRole *role,
545 BlockReopenQueue *reopen_queue,
546 uint64_t parent_perm, uint64_t parent_shared,
547 uint64_t *nperm, uint64_t *nshared);
548
549 /**
550 * Bitmaps should be marked as 'IN_USE' in the image on reopening image
551 * as rw. This handler should realize it. It also should unset readonly
552 * field of BlockDirtyBitmap's in case of success.
553 */
554 int (*bdrv_reopen_bitmaps_rw)(BlockDriverState *bs, Error **errp);
555 bool (*bdrv_can_store_new_dirty_bitmap)(BlockDriverState *bs,
556 const char *name,
557 uint32_t granularity,
558 Error **errp);
559 void (*bdrv_remove_persistent_dirty_bitmap)(BlockDriverState *bs,
560 const char *name,
561 Error **errp);
562
563 /**
564 * Register/unregister a buffer for I/O. For example, when the driver is
565 * interested to know the memory areas that will later be used in iovs, so
566 * that it can do IOMMU mapping with VFIO etc., in order to get better
567 * performance. In the case of VFIO drivers, this callback is used to do
568 * DMA mapping for hot buffers.
569 */
570 void (*bdrv_register_buf)(BlockDriverState *bs, void *host, size_t size);
571 void (*bdrv_unregister_buf)(BlockDriverState *bs, void *host);
572 QLIST_ENTRY(BlockDriver) list;
573
574 /* Pointer to a NULL-terminated array of names of strong options
575 * that can be specified for bdrv_open(). A strong option is one
576 * that changes the data of a BDS.
577 * If this pointer is NULL, the array is considered empty.
578 * "filename" and "driver" are always considered strong. */
579 const char *const *strong_runtime_opts;
580};
581
582static inline bool block_driver_can_compress(BlockDriver *drv)
583{
584 return drv->bdrv_co_pwritev_compressed ||
585 drv->bdrv_co_pwritev_compressed_part;
586}
587
588typedef struct BlockLimits {
589 /* Alignment requirement, in bytes, for offset/length of I/O
590 * requests. Must be a power of 2 less than INT_MAX; defaults to
591 * 1 for drivers with modern byte interfaces, and to 512
592 * otherwise. */
593 uint32_t request_alignment;
594
595 /* Maximum number of bytes that can be discarded at once (since it
596 * is signed, it must be < 2G, if set). Must be multiple of
597 * pdiscard_alignment, but need not be power of 2. May be 0 if no
598 * inherent 32-bit limit */
599 int32_t max_pdiscard;
600
601 /* Optimal alignment for discard requests in bytes. A power of 2
602 * is best but not mandatory. Must be a multiple of
603 * bl.request_alignment, and must be less than max_pdiscard if
604 * that is set. May be 0 if bl.request_alignment is good enough */
605 uint32_t pdiscard_alignment;
606
607 /* Maximum number of bytes that can zeroized at once (since it is
608 * signed, it must be < 2G, if set). Must be multiple of
609 * pwrite_zeroes_alignment. May be 0 if no inherent 32-bit limit */
610 int32_t max_pwrite_zeroes;
611
612 /* Optimal alignment for write zeroes requests in bytes. A power
613 * of 2 is best but not mandatory. Must be a multiple of
614 * bl.request_alignment, and must be less than max_pwrite_zeroes
615 * if that is set. May be 0 if bl.request_alignment is good
616 * enough */
617 uint32_t pwrite_zeroes_alignment;
618
619 /* Optimal transfer length in bytes. A power of 2 is best but not
620 * mandatory. Must be a multiple of bl.request_alignment, or 0 if
621 * no preferred size */
622 uint32_t opt_transfer;
623
624 /* Maximal transfer length in bytes. Need not be power of 2, but
625 * must be multiple of opt_transfer and bl.request_alignment, or 0
626 * for no 32-bit limit. For now, anything larger than INT_MAX is
627 * clamped down. */
628 uint32_t max_transfer;
629
630 /* memory alignment, in bytes so that no bounce buffer is needed */
631 size_t min_mem_alignment;
632
633 /* memory alignment, in bytes, for bounce buffer */
634 size_t opt_mem_alignment;
635
636 /* maximum number of iovec elements */
637 int max_iov;
638} BlockLimits;
639
640typedef struct BdrvOpBlocker BdrvOpBlocker;
641
642typedef struct BdrvAioNotifier {
643 void (*attached_aio_context)(AioContext *new_context, void *opaque);
644 void (*detach_aio_context)(void *opaque);
645
646 void *opaque;
647 bool deleted;
648
649 QLIST_ENTRY(BdrvAioNotifier) list;
650} BdrvAioNotifier;
651
652struct BdrvChildRole {
653 /* If true, bdrv_replace_node() doesn't change the node this BdrvChild
654 * points to. */
655 bool stay_at_node;
656
657 /* If true, the parent is a BlockDriverState and bdrv_next_all_states()
658 * will return it. This information is used for drain_all, where every node
659 * will be drained separately, so the drain only needs to be propagated to
660 * non-BDS parents. */
661 bool parent_is_bds;
662
663 void (*inherit_options)(int *child_flags, QDict *child_options,
664 int parent_flags, QDict *parent_options);
665
666 void (*change_media)(BdrvChild *child, bool load);
667 void (*resize)(BdrvChild *child);
668
669 /* Returns a name that is supposedly more useful for human users than the
670 * node name for identifying the node in question (in particular, a BB
671 * name), or NULL if the parent can't provide a better name. */
672 const char *(*get_name)(BdrvChild *child);
673
674 /* Returns a malloced string that describes the parent of the child for a
675 * human reader. This could be a node-name, BlockBackend name, qdev ID or
676 * QOM path of the device owning the BlockBackend, job type and ID etc. The
677 * caller is responsible for freeing the memory. */
678 char *(*get_parent_desc)(BdrvChild *child);
679
680 /*
681 * If this pair of functions is implemented, the parent doesn't issue new
682 * requests after returning from .drained_begin() until .drained_end() is
683 * called.
684 *
685 * These functions must not change the graph (and therefore also must not
686 * call aio_poll(), which could change the graph indirectly).
687 *
688 * If drained_end() schedules background operations, it must atomically
689 * increment *drained_end_counter for each such operation and atomically
690 * decrement it once the operation has settled.
691 *
692 * Note that this can be nested. If drained_begin() was called twice, new
693 * I/O is allowed only after drained_end() was called twice, too.
694 */
695 void (*drained_begin)(BdrvChild *child);
696 void (*drained_end)(BdrvChild *child, int *drained_end_counter);
697
698 /*
699 * Returns whether the parent has pending requests for the child. This
700 * callback is polled after .drained_begin() has been called until all
701 * activity on the child has stopped.
702 */
703 bool (*drained_poll)(BdrvChild *child);
704
705 /* Notifies the parent that the child has been activated/inactivated (e.g.
706 * when migration is completing) and it can start/stop requesting
707 * permissions and doing I/O on it. */
708 void (*activate)(BdrvChild *child, Error **errp);
709 int (*inactivate)(BdrvChild *child);
710
711 void (*attach)(BdrvChild *child);
712 void (*detach)(BdrvChild *child);
713
714 /* Notifies the parent that the filename of its child has changed (e.g.
715 * because the direct child was removed from the backing chain), so that it
716 * can update its reference. */
717 int (*update_filename)(BdrvChild *child, BlockDriverState *new_base,
718 const char *filename, Error **errp);
719
720 bool (*can_set_aio_ctx)(BdrvChild *child, AioContext *ctx,
721 GSList **ignore, Error **errp);
722 void (*set_aio_ctx)(BdrvChild *child, AioContext *ctx, GSList **ignore);
723};
724
725extern const BdrvChildRole child_file;
726extern const BdrvChildRole child_format;
727extern const BdrvChildRole child_backing;
728
729struct BdrvChild {
730 BlockDriverState *bs;
731 char *name;
732 const BdrvChildRole *role;
733 void *opaque;
734
735 /**
736 * Granted permissions for operating on this BdrvChild (BLK_PERM_* bitmask)
737 */
738 uint64_t perm;
739
740 /**
741 * Permissions that can still be granted to other users of @bs while this
742 * BdrvChild is still attached to it. (BLK_PERM_* bitmask)
743 */
744 uint64_t shared_perm;
745
746 /* backup of permissions during permission update procedure */
747 bool has_backup_perm;
748 uint64_t backup_perm;
749 uint64_t backup_shared_perm;
750
751 /*
752 * This link is frozen: the child can neither be replaced nor
753 * detached from the parent.
754 */
755 bool frozen;
756
757 /*
758 * How many times the parent of this child has been drained
759 * (through role->drained_*).
760 * Usually, this is equal to bs->quiesce_counter (potentially
761 * reduced by bdrv_drain_all_count). It may differ while the
762 * child is entering or leaving a drained section.
763 */
764 int parent_quiesce_counter;
765
766 QLIST_ENTRY(BdrvChild) next;
767 QLIST_ENTRY(BdrvChild) next_parent;
768};
769
770/*
771 * Note: the function bdrv_append() copies and swaps contents of
772 * BlockDriverStates, so if you add new fields to this struct, please
773 * inspect bdrv_append() to determine if the new fields need to be
774 * copied as well.
775 */
776struct BlockDriverState {
777 /* Protected by big QEMU lock or read-only after opening. No special
778 * locking needed during I/O...
779 */
780 int open_flags; /* flags used to open the file, re-used for re-open */
781 bool read_only; /* if true, the media is read only */
782 bool encrypted; /* if true, the media is encrypted */
783 bool sg; /* if true, the device is a /dev/sg* */
784 bool probed; /* if true, format was probed rather than specified */
785 bool force_share; /* if true, always allow all shared permissions */
786 bool implicit; /* if true, this filter node was automatically inserted */
787
788 BlockDriver *drv; /* NULL means no media */
789 void *opaque;
790
791 AioContext *aio_context; /* event loop used for fd handlers, timers, etc */
792 /* long-running tasks intended to always use the same AioContext as this
793 * BDS may register themselves in this list to be notified of changes
794 * regarding this BDS's context */
795 QLIST_HEAD(, BdrvAioNotifier) aio_notifiers;
796 bool walking_aio_notifiers; /* to make removal during iteration safe */
797
798 char filename[PATH_MAX];
799 char backing_file[PATH_MAX]; /* if non zero, the image is a diff of
800 this file image */
801 /* The backing filename indicated by the image header; if we ever
802 * open this file, then this is replaced by the resulting BDS's
803 * filename (i.e. after a bdrv_refresh_filename() run). */
804 char auto_backing_file[PATH_MAX];
805 char backing_format[16]; /* if non-zero and backing_file exists */
806
807 QDict *full_open_options;
808 char exact_filename[PATH_MAX];
809
810 BdrvChild *backing;
811 BdrvChild *file;
812
813 /* I/O Limits */
814 BlockLimits bl;
815
816 /* Flags honored during pwrite (so far: BDRV_REQ_FUA,
817 * BDRV_REQ_WRITE_UNCHANGED).
818 * If a driver does not support BDRV_REQ_WRITE_UNCHANGED, those
819 * writes will be issued as normal writes without the flag set.
820 * This is important to note for drivers that do not explicitly
821 * request a WRITE permission for their children and instead take
822 * the same permissions as their parent did (this is commonly what
823 * block filters do). Such drivers have to be aware that the
824 * parent may have taken a WRITE_UNCHANGED permission only and is
825 * issuing such requests. Drivers either must make sure that
826 * these requests do not result in plain WRITE accesses (usually
827 * by supporting BDRV_REQ_WRITE_UNCHANGED, and then forwarding
828 * every incoming write request as-is, including potentially that
829 * flag), or they have to explicitly take the WRITE permission for
830 * their children. */
831 unsigned int supported_write_flags;
832 /* Flags honored during pwrite_zeroes (so far: BDRV_REQ_FUA,
833 * BDRV_REQ_MAY_UNMAP, BDRV_REQ_WRITE_UNCHANGED) */
834 unsigned int supported_zero_flags;
835
836 /* the following member gives a name to every node on the bs graph. */
837 char node_name[32];
838 /* element of the list of named nodes building the graph */
839 QTAILQ_ENTRY(BlockDriverState) node_list;
840 /* element of the list of all BlockDriverStates (all_bdrv_states) */
841 QTAILQ_ENTRY(BlockDriverState) bs_list;
842 /* element of the list of monitor-owned BDS */
843 QTAILQ_ENTRY(BlockDriverState) monitor_list;
844 int refcnt;
845
846 /* operation blockers */
847 QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX];
848
849 /* The node that this node inherited default options from (and a reopen on
850 * which can affect this node by changing these defaults). This is always a
851 * parent node of this node. */
852 BlockDriverState *inherits_from;
853 QLIST_HEAD(, BdrvChild) children;
854 QLIST_HEAD(, BdrvChild) parents;
855
856 QDict *options;
857 QDict *explicit_options;
858 BlockdevDetectZeroesOptions detect_zeroes;
859
860 /* The error object in use for blocking operations on backing_hd */
861 Error *backing_blocker;
862
863 /* Protected by AioContext lock */
864
865 /* If we are reading a disk image, give its size in sectors.
866 * Generally read-only; it is written to by load_snapshot and
867 * save_snaphost, but the block layer is quiescent during those.
868 */
869 int64_t total_sectors;
870
871 /* Callback before write request is processed */
872 NotifierWithReturnList before_write_notifiers;
873
874 /* threshold limit for writes, in bytes. "High water mark". */
875 uint64_t write_threshold_offset;
876 NotifierWithReturn write_threshold_notifier;
877
878 /* Writing to the list requires the BQL _and_ the dirty_bitmap_mutex.
879 * Reading from the list can be done with either the BQL or the
880 * dirty_bitmap_mutex. Modifying a bitmap only requires
881 * dirty_bitmap_mutex. */
882 QemuMutex dirty_bitmap_mutex;
883 QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps;
884
885 /* Offset after the highest byte written to */
886 Stat64 wr_highest_offset;
887
888 /* If true, copy read backing sectors into image. Can be >1 if more
889 * than one client has requested copy-on-read. Accessed with atomic
890 * ops.
891 */
892 int copy_on_read;
893
894 /* number of in-flight requests; overall and serialising.
895 * Accessed with atomic ops.
896 */
897 unsigned int in_flight;
898 unsigned int serialising_in_flight;
899
900 /* counter for nested bdrv_io_plug.
901 * Accessed with atomic ops.
902 */
903 unsigned io_plugged;
904
905 /* do we need to tell the quest if we have a volatile write cache? */
906 int enable_write_cache;
907
908 /* Accessed with atomic ops. */
909 int quiesce_counter;
910 int recursive_quiesce_counter;
911
912 unsigned int write_gen; /* Current data generation */
913
914 /* Protected by reqs_lock. */
915 CoMutex reqs_lock;
916 QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
917 CoQueue flush_queue; /* Serializing flush queue */
918 bool active_flush_req; /* Flush request in flight? */
919
920 /* Only read/written by whoever has set active_flush_req to true. */
921 unsigned int flushed_gen; /* Flushed write generation */
922
923 /* BdrvChild links to this node may never be frozen */
924 bool never_freeze;
925};
926
927struct BlockBackendRootState {
928 int open_flags;
929 bool read_only;
930 BlockdevDetectZeroesOptions detect_zeroes;
931};
932
933typedef enum BlockMirrorBackingMode {
934 /* Reuse the existing backing chain from the source for the target.
935 * - sync=full: Set backing BDS to NULL.
936 * - sync=top: Use source's backing BDS.
937 * - sync=none: Use source as the backing BDS. */
938 MIRROR_SOURCE_BACKING_CHAIN,
939
940 /* Open the target's backing chain completely anew */
941 MIRROR_OPEN_BACKING_CHAIN,
942
943 /* Do not change the target's backing BDS after job completion */
944 MIRROR_LEAVE_BACKING_CHAIN,
945} BlockMirrorBackingMode;
946
947static inline BlockDriverState *backing_bs(BlockDriverState *bs)
948{
949 return bs->backing ? bs->backing->bs : NULL;
950}
951
952
953/* Essential block drivers which must always be statically linked into qemu, and
954 * which therefore can be accessed without using bdrv_find_format() */
955extern BlockDriver bdrv_file;
956extern BlockDriver bdrv_raw;
957extern BlockDriver bdrv_qcow2;
958
959int coroutine_fn bdrv_co_preadv(BdrvChild *child,
960 int64_t offset, unsigned int bytes, QEMUIOVector *qiov,
961 BdrvRequestFlags flags);
962int coroutine_fn bdrv_co_preadv_part(BdrvChild *child,
963 int64_t offset, unsigned int bytes,
964 QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags);
965int coroutine_fn bdrv_co_pwritev(BdrvChild *child,
966 int64_t offset, unsigned int bytes, QEMUIOVector *qiov,
967 BdrvRequestFlags flags);
968int coroutine_fn bdrv_co_pwritev_part(BdrvChild *child,
969 int64_t offset, unsigned int bytes,
970 QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags);
971
972static inline int coroutine_fn bdrv_co_pread(BdrvChild *child,
973 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags)
974{
975 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
976
977 return bdrv_co_preadv(child, offset, bytes, &qiov, flags);
978}
979
980static inline int coroutine_fn bdrv_co_pwrite(BdrvChild *child,
981 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags)
982{
983 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
984
985 return bdrv_co_pwritev(child, offset, bytes, &qiov, flags);
986}
987
988extern unsigned int bdrv_drain_all_count;
989void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent);
990void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent);
991
992int get_tmp_filename(char *filename, int size);
993BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
994 const char *filename);
995
996void bdrv_parse_filename_strip_prefix(const char *filename, const char *prefix,
997 QDict *options);
998
999
1000/**
1001 * bdrv_add_before_write_notifier:
1002 *
1003 * Register a callback that is invoked before write requests are processed but
1004 * after any throttling or waiting for overlapping requests.
1005 */
1006void bdrv_add_before_write_notifier(BlockDriverState *bs,
1007 NotifierWithReturn *notifier);
1008
1009/**
1010 * bdrv_add_aio_context_notifier:
1011 *
1012 * If a long-running job intends to be always run in the same AioContext as a
1013 * certain BDS, it may use this function to be notified of changes regarding the
1014 * association of the BDS to an AioContext.
1015 *
1016 * attached_aio_context() is called after the target BDS has been attached to a
1017 * new AioContext; detach_aio_context() is called before the target BDS is being
1018 * detached from its old AioContext.
1019 */
1020void bdrv_add_aio_context_notifier(BlockDriverState *bs,
1021 void (*attached_aio_context)(AioContext *new_context, void *opaque),
1022 void (*detach_aio_context)(void *opaque), void *opaque);
1023
1024/**
1025 * bdrv_remove_aio_context_notifier:
1026 *
1027 * Unsubscribe of change notifications regarding the BDS's AioContext. The
1028 * parameters given here have to be the same as those given to
1029 * bdrv_add_aio_context_notifier().
1030 */
1031void bdrv_remove_aio_context_notifier(BlockDriverState *bs,
1032 void (*aio_context_attached)(AioContext *,
1033 void *),
1034 void (*aio_context_detached)(void *),
1035 void *opaque);
1036
1037/**
1038 * bdrv_wakeup:
1039 * @bs: The BlockDriverState for which an I/O operation has been completed.
1040 *
1041 * Wake up the main thread if it is waiting on BDRV_POLL_WHILE. During
1042 * synchronous I/O on a BlockDriverState that is attached to another
1043 * I/O thread, the main thread lets the I/O thread's event loop run,
1044 * waiting for the I/O operation to complete. A bdrv_wakeup will wake
1045 * up the main thread if necessary.
1046 *
1047 * Manual calls to bdrv_wakeup are rarely necessary, because
1048 * bdrv_dec_in_flight already calls it.
1049 */
1050void bdrv_wakeup(BlockDriverState *bs);
1051
1052#ifdef _WIN32
1053int is_windows_drive(const char *filename);
1054#endif
1055
1056/**
1057 * stream_start:
1058 * @job_id: The id of the newly-created job, or %NULL to use the
1059 * device name of @bs.
1060 * @bs: Block device to operate on.
1061 * @base: Block device that will become the new base, or %NULL to
1062 * flatten the whole backing file chain onto @bs.
1063 * @backing_file_str: The file name that will be written to @bs as the
1064 * the new backing file if the job completes. Ignored if @base is %NULL.
1065 * @creation_flags: Flags that control the behavior of the Job lifetime.
1066 * See @BlockJobCreateFlags
1067 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
1068 * @on_error: The action to take upon error.
1069 * @errp: Error object.
1070 *
1071 * Start a streaming operation on @bs. Clusters that are unallocated
1072 * in @bs, but allocated in any image between @base and @bs (both
1073 * exclusive) will be written to @bs. At the end of a successful
1074 * streaming job, the backing file of @bs will be changed to
1075 * @backing_file_str in the written image and to @base in the live
1076 * BlockDriverState.
1077 */
1078void stream_start(const char *job_id, BlockDriverState *bs,
1079 BlockDriverState *base, const char *backing_file_str,
1080 int creation_flags, int64_t speed,
1081 BlockdevOnError on_error, Error **errp);
1082
1083/**
1084 * commit_start:
1085 * @job_id: The id of the newly-created job, or %NULL to use the
1086 * device name of @bs.
1087 * @bs: Active block device.
1088 * @top: Top block device to be committed.
1089 * @base: Block device that will be written into, and become the new top.
1090 * @creation_flags: Flags that control the behavior of the Job lifetime.
1091 * See @BlockJobCreateFlags
1092 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
1093 * @on_error: The action to take upon error.
1094 * @backing_file_str: String to use as the backing file in @top's overlay
1095 * @filter_node_name: The node name that should be assigned to the filter
1096 * driver that the commit job inserts into the graph above @top. NULL means
1097 * that a node name should be autogenerated.
1098 * @errp: Error object.
1099 *
1100 */
1101void commit_start(const char *job_id, BlockDriverState *bs,
1102 BlockDriverState *base, BlockDriverState *top,
1103 int creation_flags, int64_t speed,
1104 BlockdevOnError on_error, const char *backing_file_str,
1105 const char *filter_node_name, Error **errp);
1106/**
1107 * commit_active_start:
1108 * @job_id: The id of the newly-created job, or %NULL to use the
1109 * device name of @bs.
1110 * @bs: Active block device to be committed.
1111 * @base: Block device that will be written into, and become the new top.
1112 * @creation_flags: Flags that control the behavior of the Job lifetime.
1113 * See @BlockJobCreateFlags
1114 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
1115 * @on_error: The action to take upon error.
1116 * @filter_node_name: The node name that should be assigned to the filter
1117 * driver that the commit job inserts into the graph above @bs. NULL means that
1118 * a node name should be autogenerated.
1119 * @cb: Completion function for the job.
1120 * @opaque: Opaque pointer value passed to @cb.
1121 * @auto_complete: Auto complete the job.
1122 * @errp: Error object.
1123 *
1124 */
1125BlockJob *commit_active_start(const char *job_id, BlockDriverState *bs,
1126 BlockDriverState *base, int creation_flags,
1127 int64_t speed, BlockdevOnError on_error,
1128 const char *filter_node_name,
1129 BlockCompletionFunc *cb, void *opaque,
1130 bool auto_complete, Error **errp);
1131/*
1132 * mirror_start:
1133 * @job_id: The id of the newly-created job, or %NULL to use the
1134 * device name of @bs.
1135 * @bs: Block device to operate on.
1136 * @target: Block device to write to.
1137 * @replaces: Block graph node name to replace once the mirror is done. Can
1138 * only be used when full mirroring is selected.
1139 * @creation_flags: Flags that control the behavior of the Job lifetime.
1140 * See @BlockJobCreateFlags
1141 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
1142 * @granularity: The chosen granularity for the dirty bitmap.
1143 * @buf_size: The amount of data that can be in flight at one time.
1144 * @mode: Whether to collapse all images in the chain to the target.
1145 * @backing_mode: How to establish the target's backing chain after completion.
1146 * @zero_target: Whether the target should be explicitly zero-initialized
1147 * @on_source_error: The action to take upon error reading from the source.
1148 * @on_target_error: The action to take upon error writing to the target.
1149 * @unmap: Whether to unmap target where source sectors only contain zeroes.
1150 * @filter_node_name: The node name that should be assigned to the filter
1151 * driver that the mirror job inserts into the graph above @bs. NULL means that
1152 * a node name should be autogenerated.
1153 * @copy_mode: When to trigger writes to the target.
1154 * @errp: Error object.
1155 *
1156 * Start a mirroring operation on @bs. Clusters that are allocated
1157 * in @bs will be written to @target until the job is cancelled or
1158 * manually completed. At the end of a successful mirroring job,
1159 * @bs will be switched to read from @target.
1160 */
1161void mirror_start(const char *job_id, BlockDriverState *bs,
1162 BlockDriverState *target, const char *replaces,
1163 int creation_flags, int64_t speed,
1164 uint32_t granularity, int64_t buf_size,
1165 MirrorSyncMode mode, BlockMirrorBackingMode backing_mode,
1166 bool zero_target,
1167 BlockdevOnError on_source_error,
1168 BlockdevOnError on_target_error,
1169 bool unmap, const char *filter_node_name,
1170 MirrorCopyMode copy_mode, Error **errp);
1171
1172/*
1173 * backup_job_create:
1174 * @job_id: The id of the newly-created job, or %NULL to use the
1175 * device name of @bs.
1176 * @bs: Block device to operate on.
1177 * @target: Block device to write to.
1178 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
1179 * @sync_mode: What parts of the disk image should be copied to the destination.
1180 * @sync_bitmap: The dirty bitmap if sync_mode is 'bitmap' or 'incremental'
1181 * @bitmap_mode: The bitmap synchronization policy to use.
1182 * @on_source_error: The action to take upon error reading from the source.
1183 * @on_target_error: The action to take upon error writing to the target.
1184 * @creation_flags: Flags that control the behavior of the Job lifetime.
1185 * See @BlockJobCreateFlags
1186 * @cb: Completion function for the job.
1187 * @opaque: Opaque pointer value passed to @cb.
1188 * @txn: Transaction that this job is part of (may be NULL).
1189 *
1190 * Create a backup operation on @bs. Clusters in @bs are written to @target
1191 * until the job is cancelled or manually completed.
1192 */
1193BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
1194 BlockDriverState *target, int64_t speed,
1195 MirrorSyncMode sync_mode,
1196 BdrvDirtyBitmap *sync_bitmap,
1197 BitmapSyncMode bitmap_mode,
1198 bool compress,
1199 BlockdevOnError on_source_error,
1200 BlockdevOnError on_target_error,
1201 int creation_flags,
1202 BlockCompletionFunc *cb, void *opaque,
1203 JobTxn *txn, Error **errp);
1204
1205void hmp_drive_add_node(Monitor *mon, const char *optstr);
1206
1207BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs,
1208 const char *child_name,
1209 const BdrvChildRole *child_role,
1210 AioContext *ctx,
1211 uint64_t perm, uint64_t shared_perm,
1212 void *opaque, Error **errp);
1213void bdrv_root_unref_child(BdrvChild *child);
1214
1215/**
1216 * Sets a BdrvChild's permissions. Avoid if the parent is a BDS; use
1217 * bdrv_child_refresh_perms() instead and make the parent's
1218 * .bdrv_child_perm() implementation return the correct values.
1219 */
1220int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared,
1221 Error **errp);
1222
1223/**
1224 * Calls bs->drv->bdrv_child_perm() and updates the child's permission
1225 * masks with the result.
1226 * Drivers should invoke this function whenever an event occurs that
1227 * makes their .bdrv_child_perm() implementation return different
1228 * values than before, but which will not result in the block layer
1229 * automatically refreshing the permissions.
1230 */
1231int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp);
1232
1233/* Default implementation for BlockDriver.bdrv_child_perm() that can be used by
1234 * block filters: Forward CONSISTENT_READ, WRITE, WRITE_UNCHANGED and RESIZE to
1235 * all children */
1236void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c,
1237 const BdrvChildRole *role,
1238 BlockReopenQueue *reopen_queue,
1239 uint64_t perm, uint64_t shared,
1240 uint64_t *nperm, uint64_t *nshared);
1241
1242/* Default implementation for BlockDriver.bdrv_child_perm() that can be used by
1243 * (non-raw) image formats: Like above for bs->backing, but for bs->file it
1244 * requires WRITE | RESIZE for read-write images, always requires
1245 * CONSISTENT_READ and doesn't share WRITE. */
1246void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c,
1247 const BdrvChildRole *role,
1248 BlockReopenQueue *reopen_queue,
1249 uint64_t perm, uint64_t shared,
1250 uint64_t *nperm, uint64_t *nshared);
1251
1252/*
1253 * Default implementation for drivers to pass bdrv_co_block_status() to
1254 * their file.
1255 */
1256int coroutine_fn bdrv_co_block_status_from_file(BlockDriverState *bs,
1257 bool want_zero,
1258 int64_t offset,
1259 int64_t bytes,
1260 int64_t *pnum,
1261 int64_t *map,
1262 BlockDriverState **file);
1263/*
1264 * Default implementation for drivers to pass bdrv_co_block_status() to
1265 * their backing file.
1266 */
1267int coroutine_fn bdrv_co_block_status_from_backing(BlockDriverState *bs,
1268 bool want_zero,
1269 int64_t offset,
1270 int64_t bytes,
1271 int64_t *pnum,
1272 int64_t *map,
1273 BlockDriverState **file);
1274const char *bdrv_get_parent_name(const BlockDriverState *bs);
1275void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp);
1276bool blk_dev_has_removable_media(BlockBackend *blk);
1277bool blk_dev_has_tray(BlockBackend *blk);
1278void blk_dev_eject_request(BlockBackend *blk, bool force);
1279bool blk_dev_is_tray_open(BlockBackend *blk);
1280bool blk_dev_is_medium_locked(BlockBackend *blk);
1281
1282void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes);
1283
1284void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out);
1285void bdrv_restore_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *backup);
1286bool bdrv_dirty_bitmap_merge_internal(BdrvDirtyBitmap *dest,
1287 const BdrvDirtyBitmap *src,
1288 HBitmap **backup, bool lock);
1289
1290void bdrv_inc_in_flight(BlockDriverState *bs);
1291void bdrv_dec_in_flight(BlockDriverState *bs);
1292
1293void blockdev_close_all_bdrv_states(void);
1294
1295int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, uint64_t src_offset,
1296 BdrvChild *dst, uint64_t dst_offset,
1297 uint64_t bytes,
1298 BdrvRequestFlags read_flags,
1299 BdrvRequestFlags write_flags);
1300int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, uint64_t src_offset,
1301 BdrvChild *dst, uint64_t dst_offset,
1302 uint64_t bytes,
1303 BdrvRequestFlags read_flags,
1304 BdrvRequestFlags write_flags);
1305
1306int refresh_total_sectors(BlockDriverState *bs, int64_t hint);
1307
1308#endif /* BLOCK_INT_H */
1309