qemu/include/hw/virtio/virtio-blk.h
Michael S. Tsirkin 8a2fad57eb virtio-blk: use aio handler for data plane
In addition to handling IO in vcpu thread and in io thread, dataplane
introduces yet another mode: handling it by AioContext.

This reuses the same handler as previous modes, which triggers races as
these were not designed to be reentrant.  Use a separate handler just
for aio, and disable regular handlers when dataplane is active.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-04-07 19:57:33 +03:00

92 lines
2.1 KiB
C

/*
* Virtio Block Device
*
* Copyright IBM, Corp. 2007
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#ifndef _QEMU_VIRTIO_BLK_H
#define _QEMU_VIRTIO_BLK_H
#include "standard-headers/linux/virtio_blk.h"
#include "hw/virtio/virtio.h"
#include "hw/block/block.h"
#include "sysemu/iothread.h"
#include "sysemu/block-backend.h"
#define TYPE_VIRTIO_BLK "virtio-blk-device"
#define VIRTIO_BLK(obj) \
OBJECT_CHECK(VirtIOBlock, (obj), TYPE_VIRTIO_BLK)
/* This is the last element of the write scatter-gather list */
struct virtio_blk_inhdr
{
unsigned char status;
};
struct VirtIOBlkConf
{
BlockConf conf;
IOThread *iothread;
char *serial;
uint32_t scsi;
uint32_t config_wce;
uint32_t request_merging;
};
struct VirtIOBlockDataPlane;
struct VirtIOBlockReq;
typedef struct VirtIOBlock {
VirtIODevice parent_obj;
BlockBackend *blk;
VirtQueue *vq;
void *rq;
QEMUBH *bh;
VirtIOBlkConf conf;
unsigned short sector_mask;
bool original_wce;
VMChangeStateEntry *change;
bool dataplane_disabled;
bool dataplane_started;
struct VirtIOBlockDataPlane *dataplane;
} VirtIOBlock;
typedef struct VirtIOBlockReq {
VirtQueueElement elem;
int64_t sector_num;
VirtIOBlock *dev;
struct virtio_blk_inhdr *in;
struct virtio_blk_outhdr out;
QEMUIOVector qiov;
size_t in_len;
struct VirtIOBlockReq *next;
struct VirtIOBlockReq *mr_next;
BlockAcctCookie acct;
} VirtIOBlockReq;
#define VIRTIO_BLK_MAX_MERGE_REQS 32
typedef struct MultiReqBuffer {
VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS];
unsigned int num_reqs;
bool is_write;
} MultiReqBuffer;
void virtio_blk_init_request(VirtIOBlock *s, VirtIOBlockReq *req);
void virtio_blk_free_request(VirtIOBlockReq *req);
void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb);
void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb);
void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq);
#endif