LXR qemu/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
  21typedef 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
  28typedef void (*ProgressBytesCallbackFunc)(int64_t bytes, void *opaque);
  29typedef void (*ProgressResetCallbackFunc)(void *opaque);
  30typedef 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
  77BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
  78                                     int64_t cluster_size,
  79                                     BdrvRequestFlags write_flags,
  80                                     Error **errp);
  81
  82void block_copy_set_callbacks(
  83        BlockCopyState *s,
  84        ProgressBytesCallbackFunc progress_bytes_callback,
  85        ProgressResetCallbackFunc progress_reset_callback,
  86        void *progress_opaque);
  87
  88void block_copy_state_free(BlockCopyState *s);
  89
  90int64_t block_copy_reset_unallocated(BlockCopyState *s,
  91                                     int64_t offset, int64_t *count);
  92
  93int coroutine_fn block_copy(BlockCopyState *s, int64_t start, uint64_t bytes,
  94                            bool *error_is_read);
  95
  96#endif /* BLOCK_COPY_H */
  97