include/block/block-copy.h

   1 /*
   2  * block_copy API
   3  *
   4  * Copyright (C) 2013 Proxmox Server Solutions
   5  * Copyright (c) 2019 Virtuozzo International GmbH.
   6  *
   7  * Authors:
   8  *  Dietmar Maurer (dietmar@proxmox.com)
   9  *  Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
  10  *
  11  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  12  * See the COPYING file in the top-level directory.
  13  */
  14
  15 #ifndef BLOCK_COPY_H
  16 #define BLOCK_COPY_H
  17
  18 #include "block/block.h"
  19 #include "qemu/co-shared-resource.h"
  20
  21 typedef struct BlockCopyInFlightReq {
  22     int64_t start_byte;
  23     int64_t end_byte;
  24     QLIST_ENTRY(BlockCopyInFlightReq) list;
  25     CoQueue wait_queue; /* coroutines blocked on this request */
  26 } BlockCopyInFlightReq;
  27
  28 typedef void (*ProgressBytesCallbackFunc)(int64_t bytes, void *opaque);
  29 typedef void (*ProgressResetCallbackFunc)(void *opaque);
  30 typedef struct BlockCopyState {
  31     /*
  32      * BdrvChild objects are not owned or managed by block-copy. They are
  33      * provided by block-copy user and user is responsible for appropriate
  34      * permissions on these children.
  35      */
  36     BdrvChild *source;
  37     BdrvChild *target;
  38     BdrvDirtyBitmap *copy_bitmap;
  39     int64_t cluster_size;
  40     bool use_copy_range;
  41     int64_t copy_size;
  42     uint64_t len;
  43     QLIST_HEAD(, BlockCopyInFlightReq) inflight_reqs;
  44
  45     BdrvRequestFlags write_flags;
  46
  47     /*
  48      * skip_unallocated:
  49      *
  50      * Used by sync=top jobs, which first scan the source node for unallocated
  51      * areas and clear them in the copy_bitmap.  During this process, the bitmap
  52      * is thus not fully initialized: It may still have bits set for areas that
  53      * are unallocated and should actually not be copied.
  54      *
  55      * This is indicated by skip_unallocated.
  56      *
  57      * In this case, block_copy() will query the source’s allocation status,
  58      * skip unallocated regions, clear them in the copy_bitmap, and invoke
  59      * block_copy_reset_unallocated() every time it does.
  60      */
  61     bool skip_unallocated;
  62
  63     /* progress_bytes_callback: called when some copying progress is done. */
  64     ProgressBytesCallbackFunc progress_bytes_callback;
  65
  66     /*
  67      * progress_reset_callback: called when some bytes reset from copy_bitmap
  68      * (see @skip_unallocated above). The callee is assumed to recalculate how
  69      * many bytes remain based on the dirty bit count of copy_bitmap.
  70      */
  71     ProgressResetCallbackFunc progress_reset_callback;
  72     void *progress_opaque;
  73
  74     SharedResource *mem;
  75 } BlockCopyState;
  76
  77 BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
  78                                      int64_t cluster_size,
  79                                      BdrvRequestFlags write_flags,
  80                                      Error **errp);
  81
  82 void block_copy_set_callbacks(
  83         BlockCopyState *s,
  84         ProgressBytesCallbackFunc progress_bytes_callback,
  85         ProgressResetCallbackFunc progress_reset_callback,
  86         void *progress_opaque);
  87
  88 void block_copy_state_free(BlockCopyState *s);
  89
  90 int64_t block_copy_reset_unallocated(BlockCopyState *s,
  91                                      int64_t offset, int64_t *count);
  92
  93 int coroutine_fn block_copy(BlockCopyState *s, int64_t start, uint64_t bytes,
  94                             bool *error_is_read);
  95
  96 #endif /* BLOCK_COPY_H */