qemu/include/hw/virtio/virtio-blk.h
Stefan Hajnoczi baf422684d virtio-blk: use BDRV_REQ_REGISTERED_BUF optimization hint
Register guest RAM using BlockRAMRegistrar and set the
BDRV_REQ_REGISTERED_BUF flag so block drivers can optimize memory
accesses in I/O requests.

This is for vdpa-blk, vhost-user-blk, and other I/O interfaces that rely
on DMA mapping/unmapping.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20221013185908.1297568-14-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-10-26 14:56:42 -04:00

99 lines
2.3 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"
#include "sysemu/block-ram-registrar.h"
#include "qom/object.h"
#define TYPE_VIRTIO_BLK "virtio-blk-device"
OBJECT_DECLARE_SIMPLE_TYPE(VirtIOBlock, VIRTIO_BLK)
/* This is the last element of the write scatter-gather list */
struct virtio_blk_inhdr
{
unsigned char status;
};
#define VIRTIO_BLK_AUTO_NUM_QUEUES UINT16_MAX
struct VirtIOBlkConf
{
BlockConf conf;
IOThread *iothread;
char *serial;
uint32_t request_merging;
uint16_t num_queues;
uint16_t queue_size;
bool seg_max_adjust;
bool report_discard_granularity;
uint32_t max_discard_sectors;
uint32_t max_write_zeroes_sectors;
bool x_enable_wce_if_config_wce;
};
struct VirtIOBlockDataPlane;
struct VirtIOBlockReq;
struct VirtIOBlock {
VirtIODevice parent_obj;
BlockBackend *blk;
void *rq;
QEMUBH *bh;
VirtIOBlkConf conf;
unsigned short sector_mask;
bool original_wce;
VMChangeStateEntry *change;
bool dataplane_disabled;
bool dataplane_started;
struct VirtIOBlockDataPlane *dataplane;
uint64_t host_features;
size_t config_size;
BlockRAMRegistrar blk_ram_registrar;
};
typedef struct VirtIOBlockReq {
VirtQueueElement elem;
int64_t sector_num;
VirtIOBlock *dev;
VirtQueue *vq;
IOVDiscardUndo inhdr_undo;
IOVDiscardUndo outhdr_undo;
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_handle_vq(VirtIOBlock *s, VirtQueue *vq);
void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh);
#endif