#define BLOCK_H
#include "block/aio.h"
-#include "qapi-types.h"
+#include "qapi/qapi-types-block-core.h"
+#include "block/aio-wait.h"
#include "qemu/iov.h"
#include "qemu/coroutine.h"
#include "block/accounting.h"
* to the LBPRZ flag in the SCSI logical block provisioning page.
*/
bool unallocated_blocks_are_zero;
- /*
- * True if the driver can optimize writing zeroes by unmapping
- * sectors. This is equivalent to the BLKDISCARDZEROES ioctl in Linux
- * with the difference that in qemu a discard is allowed to silently
- * fail. Therefore we have to use bdrv_pwrite_zeroes with the
- * BDRV_REQ_MAY_UNMAP flag for an optimized zero write with unmapping.
- * After this call the driver has to guarantee that the contents read
- * back as zero. It is additionally required that the block device is
- * opened with BDRV_O_UNMAP flag for this to work.
- */
- bool can_write_zeroes_with_unmap;
/*
* True if this block driver only supports compressed writes
*/
* BDRV_BLOCK_ZERO: offset reads as zero
* BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data
* BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
- * layer (short for DATA || ZERO), set by block layer
- * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this layer
+ * layer rather than any backing, set by block layer
+ * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this
+ * layer, set by block layer
*
* Internal flag:
* BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request
* that the block layer recompute the answer from the returned
* BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID.
*
- * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 (BDRV_BLOCK_OFFSET_MASK) of
- * the return value (old interface) or the entire map parameter (new
- * interface) represent the offset in the returned BDS that is allocated for
- * the corresponding raw data. However, whether that offset actually
- * contains data also depends on BDRV_BLOCK_DATA, as follows:
+ * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the
+ * host offset within the returned BDS that is allocated for the
+ * corresponding raw guest data. However, whether that offset
+ * actually contains data also depends on BDRV_BLOCK_DATA, as follows:
*
* DATA ZERO OFFSET_VALID
* t t t sectors read as zero, returned file is zero at offset
void bdrv_init(void);
void bdrv_init_with_whitelist(void);
bool bdrv_uses_whitelist(void);
+int bdrv_is_whitelisted(BlockDriver *drv, bool read_only);
BlockDriver *bdrv_find_protocol(const char *filename,
bool allow_protocol_prefix,
Error **errp);
BlockDriverState* parent,
const BdrvChildRole *child_role,
bool allow_none, Error **errp);
+BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp);
void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd,
Error **errp);
int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options,
void bdrv_drain_all_end(void);
void bdrv_drain_all(void);
+/* Returns NULL when bs == NULL */
+AioWait *bdrv_get_aio_wait(BlockDriverState *bs);
+
#define BDRV_POLL_WHILE(bs, cond) ({ \
- bool waited_ = false; \
- bool busy_ = true; \
BlockDriverState *bs_ = (bs); \
- AioContext *ctx_ = bdrv_get_aio_context(bs_); \
- if (aio_context_in_iothread(ctx_)) { \
- while ((cond) || busy_) { \
- busy_ = aio_poll(ctx_, (cond)); \
- waited_ |= !!(cond) | busy_; \
- } \
- } else { \
- assert(qemu_get_current_aio_context() == \
- qemu_get_aio_context()); \
- /* Ask bdrv_dec_in_flight to wake up the main \
- * QEMU AioContext. Extra I/O threads never take \
- * other I/O threads' AioContexts (see for example \
- * block_job_defer_to_main_loop for how to do it). \
- */ \
- assert(!bs_->wakeup); \
- /* Set bs->wakeup before evaluating cond. */ \
- atomic_mb_set(&bs_->wakeup, true); \
- while (busy_) { \
- if ((cond)) { \
- waited_ = busy_ = true; \
- aio_context_release(ctx_); \
- aio_poll(qemu_get_aio_context(), true); \
- aio_context_acquire(ctx_); \
- } else { \
- busy_ = aio_poll(ctx_, false); \
- waited_ |= busy_; \
- } \
- } \
- atomic_set(&bs_->wakeup, false); \
- } \
- waited_; })
+ AIO_WAIT_WHILE(bdrv_get_aio_wait(bs_), \
+ bdrv_get_aio_context(bs_), \
+ cond); })
int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int bytes);
int bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes);