diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/block/block.h | 32 | ||||
| -rw-r--r-- | include/block/block_int.h | 38 |
2 files changed, 70 insertions, 0 deletions
diff --git a/include/block/block.h b/include/block/block.h index 3894edda9d..6cc6c7e699 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -611,4 +611,36 @@ bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, */ void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); void bdrv_unregister_buf(BlockDriverState *bs, void *host); + +/** + * + * bdrv_co_copy_range: + * + * Do offloaded copy between two children. If the operation is not implemented + * by the driver, or if the backend storage doesn't support it, a negative + * error code will be returned. + * + * Note: block layer doesn't emulate or fallback to a bounce buffer approach + * because usually the caller shouldn't attempt offloaded copy any more (e.g. + * calling copy_file_range(2)) after the first error, thus it should fall back + * to a read+write path in the caller level. + * + * @src: Source child to copy data from + * @src_offset: offset in @src image to read data + * @dst: Destination child to copy data to + * @dst_offset: offset in @dst image to write data + * @bytes: number of bytes to copy + * @flags: request flags. Must be one of: + * 0 - actually read data from src; + * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero + * write on @dst as if bdrv_co_pwrite_zeroes is + * called. Used to simplify caller code, or + * during BlockDriver.bdrv_co_copy_range_from() + * recursion. + * + * Returns: 0 if succeeded; negative error code if failed. + **/ +int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset, + BdrvChild *dst, uint64_t dst_offset, + uint64_t bytes, BdrvRequestFlags flags); #endif diff --git a/include/block/block_int.h b/include/block/block_int.h index 6c0927bce3..888b7f7bff 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -204,6 +204,37 @@ struct BlockDriver { int coroutine_fn (*bdrv_co_pdiscard)(BlockDriverState *bs, int64_t offset, int bytes); + /* Map [offset, offset + nbytes) range onto a child of @bs to copy from, + * and invoke bdrv_co_copy_range_from(child, ...), or invoke + * bdrv_co_copy_range_to() if @bs is the leaf child to copy data from. + * + * See the comment of bdrv_co_copy_range for the parameter and return value + * semantics. + */ + int coroutine_fn (*bdrv_co_copy_range_from)(BlockDriverState *bs, + BdrvChild *src, + uint64_t offset, + BdrvChild *dst, + uint64_t dst_offset, + uint64_t bytes, + BdrvRequestFlags flags); + + /* Map [offset, offset + nbytes) range onto a child of bs to copy data to, + * and invoke bdrv_co_copy_range_to(child, src, ...), or perform the copy + * operation if @bs is the leaf and @src has the same BlockDriver. Return + * -ENOTSUP if @bs is the leaf but @src has a different BlockDriver. + * + * See the comment of bdrv_co_copy_range for the parameter and return value + * semantics. + */ + int coroutine_fn (*bdrv_co_copy_range_to)(BlockDriverState *bs, + BdrvChild *src, + uint64_t src_offset, + BdrvChild *dst, + uint64_t dst_offset, + uint64_t bytes, + BdrvRequestFlags flags); + /* * Building block for bdrv_block_status[_above] and * bdrv_is_allocated[_above]. The driver should answer only @@ -1102,4 +1133,11 @@ void bdrv_dec_in_flight(BlockDriverState *bs); void blockdev_close_all_bdrv_states(void); +int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, uint64_t src_offset, + BdrvChild *dst, uint64_t dst_offset, + uint64_t bytes, BdrvRequestFlags flags); +int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, uint64_t src_offset, + BdrvChild *dst, uint64_t dst_offset, + uint64_t bytes, BdrvRequestFlags flags); + #endif /* BLOCK_INT_H */ |