include/block/block-common.h

21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
27 #include "qapi/qapi-types-block-core.h"
31  * co_wrapper{*}: Function specifiers used by block-coroutine-wrapper.py
34  * generated by scripts/block-coroutine-wrapper.py
36  * Usage: read docs/devel/block-coroutine-wrapper.rst
39  * - co_wrapper functions can be called by only non-coroutine context, because
40  *   they always generate a new coroutine.
41  * - co_wrapper_mixed functions can be called by both coroutine and
42  *   non-coroutine context.
43  * - co_wrapper_bdrv_rdlock are co_wrapper functions but automatically take and
44  *   release the graph rdlock when creating a new coroutine
45  * - co_wrapper_mixed_bdrv_rdlock are co_wrapper_mixed functions but
47  *   coroutine.
58  * no_co_wrapper: Function specifier used by block-coroutine-wrapper.py
61  * scripts/block-coroutine-wrapper.py.
64  * functions that must not be called in coroutine context. It achieves this by
65  * scheduling a BH in the bottom half that runs the respective non-coroutine
66  * function. The coroutine yields after scheduling the BH and is reentered when
94     BLK_Z_HM = 0x1, /* Host-managed zoned block device */
95     BLK_Z_HA = 0x2, /* Host-aware zoned block device */
117  * Provides information on a zone with all position and size values in bytes.
168      * driver if the block device is opened with BDRV_O_UNMAP.
176      * Code that replaces the user's QEMUIOVector elements with bounce buffers
191      * Forces request serialisation. Use only with write requests.
203      * BDRV_REQ_PREFETCH makes sense only in the context of copy-on-read
204      * (i.e., together with the BDRV_REQ_COPY_ON_READ flag or when a COR
213      * only together with BDRV_REQ_SERIALISING. Used only with requests aligned
242 #define BDRV_O_AUTO_RDONLY 0x20000 /* degrade to read-only if opening
243                                       read-write fails */
246 #define BDRV_O_CBW_DISCARD_SOURCE 0x80000 /* for copy-before-write filter */
255 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush"
256 #define BDRV_OPT_READ_ONLY      "read-only"
257 #define BDRV_OPT_AUTO_READ_ONLY "auto-read-only"
259 #define BDRV_OPT_FORCE_SHARE    "force-share"
306  *                     returned region. Only valid together with both
308  *                     appear with BDRV_BLOCK_ZERO.
337  * Block status hints: the bitwise-or of these flags emphasize what
388      * self-consistent, representing the contents of a disk at a specific
414      * There was a now-removed bit BLK_PERM_GRAPH_MOD, with value of 0x10. QEMU
415      * 6.1 and earlier may still lock the corresponding byte in block/file-posix
417      * not interfere with this old unused thing.
438  * = Connection with bs->children, bs->file and bs->backing fields =
442  * Filter drivers have drv->is_filter = true.
446  * copy-before-write filter, which also has its target DATA child).
450  * For most filters, the filtered child is linked in bs->file, bs->backing is
452  * drivers will have drv->filtered_child_is_backing set to true (see that
455  * 2. "raw" driver (block/raw-format.c)
457  * Formally it's not a filter (drv->is_filter = false)
459  * bs->backing is always NULL
461  * Only has one child, linked in bs->file. Its role is either FILTERED|PRIMARY
468  * May have at most one COW child. In this case it's linked in bs->backing.
469  * Otherwise bs->backing is NULL. COW child is never PRIMARY.
471  * May have at most one PRIMARY child. In this case it's linked in bs->file.
472  * Otherwise bs->file is NULL.
485      * Any node may have an arbitrary number of metadata-storing
494      * This flag is mutually exclusive with DATA, METADATA, and COW.
503      * This field is mutually exclusive with DATA, METADATA, and