qemu/include/hw/virtio/vhost.h

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#ifndef VHOST_H
#define VHOST_H
#include "hw/virtio/vhost-backend.h"
#include "hw/virtio/virtio.h"
#include "exec/memory.h"
/* Generic structures common for any vhost based device. */
struct vhost_inflight {
int fd;
void *addr;
uint64_t size;
uint64_t offset;
uint16_t queue_size;
};
struct vhost_virtqueue {
int kick;
int call;
void *desc;
void *avail;
void *used;
int num;
unsigned long long desc_phys;
unsigned desc_size;
unsigned long long avail_phys;
unsigned avail_size;
unsigned long long used_phys;
unsigned used_size;
EventNotifier masked_notifier;
EventNotifier error_notifier;
struct vhost_dev *dev;
};
typedef unsigned long vhost_log_chunk_t;
#define VHOST_LOG_PAGE 0x1000
#define VHOST_LOG_BITS (8 * sizeof(vhost_log_chunk_t))
#define VHOST_LOG_CHUNK (VHOST_LOG_PAGE * VHOST_LOG_BITS)
#define VHOST_INVALID_FEATURE_BIT (0xff)
struct vhost_log {
unsigned long long size;
int refcnt;
int fd;
vhost_log_chunk_t *log;
};
struct vhost_dev;
struct vhost_iommu {
struct vhost_dev *hdev;
MemoryRegion *mr;
hwaddr iommu_offset;
IOMMUNotifier n;
QLIST_ENTRY(vhost_iommu) iommu_next;
};
typedef struct VhostDevConfigOps {
/* Vhost device config space changed callback
*/
int (*vhost_dev_config_notifier)(struct vhost_dev *dev);
} VhostDevConfigOps;
struct vhost_memory;
/**
* struct vhost_dev - common vhost_dev structure
* @vhost_ops: backend specific ops
* @config_ops: ops for config changes (see @vhost_dev_set_config_notifier)
*/
struct vhost_dev {
VirtIODevice *vdev;
MemoryListener memory_listener;
MemoryListener iommu_listener;
struct vhost_memory *mem;
int n_mem_sections;
MemoryRegionSection *mem_sections;
int n_tmp_sections;
MemoryRegionSection *tmp_sections;
struct vhost_virtqueue *vqs;
unsigned int nvqs;
/* the first virtqueue which would be used by this vhost dev */
int vq_index;
/* one past the last vq index for the virtio device (not vhost) */
int vq_index_end;
/* if non-zero, minimum required value for max_queues */
int num_queues;
uint64_t features;
/** @acked_features: final set of negotiated features */
uint64_t acked_features;
/** @backend_features: backend specific feature bits */
uint64_t backend_features;
/** @protocol_features: final negotiated protocol features */
uint64_t protocol_features;
uint64_t max_queues;
uint64_t backend_cap;
/* @started: is the vhost device started? */
bool started;
bool log_enabled;
uint64_t log_size;
Error *migration_blocker;
const VhostOps *vhost_ops;
void *opaque;
struct vhost_log *log;
QLIST_ENTRY(vhost_dev) entry;
QLIST_HEAD(, vhost_iommu) iommu_list;
IOMMUNotifier n;
const VhostDevConfigOps *config_ops;
};
extern const VhostOps kernel_ops;
extern const VhostOps user_ops;
extern const VhostOps vdpa_ops;
struct vhost_net {
struct vhost_dev dev;
struct vhost_virtqueue vqs[2];
int backend;
NetClientState *nc;
};
/**
* vhost_dev_init() - initialise the vhost interface
* @hdev: the common vhost_dev structure
* @opaque: opaque ptr passed to backend (vhost/vhost-user/vdpa)
* @backend_type: type of backend
* @busyloop_timeout: timeout for polling virtqueue
* @errp: error handle
*
* The initialisation of the vhost device will trigger the
* initialisation of the backend and potentially capability
* negotiation of backend interface. Configuration of the VirtIO
* itself won't happen until the interface is started.
*
* Return: 0 on success, non-zero on error while setting errp.
*/
int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
VhostBackendType backend_type,
uint32_t busyloop_timeout, Error **errp);
/**
* vhost_dev_cleanup() - tear down and cleanup vhost interface
* @hdev: the common vhost_dev structure
*/
void vhost_dev_cleanup(struct vhost_dev *hdev);
/**
* vhost_dev_enable_notifiers() - enable event notifiers
* @hdev: common vhost_dev structure
* @vdev: the VirtIODevice structure
*
* Enable notifications directly to the vhost device rather than being
* triggered by QEMU itself. Notifications should be enabled before
* the vhost device is started via @vhost_dev_start.
*
* Return: 0 on success, < 0 on error.
*/
int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev);
/**
* vhost_dev_disable_notifiers - disable event notifications
* @hdev: common vhost_dev structure
* @vdev: the VirtIODevice structure
*
* Disable direct notifications to vhost device.
*/
void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev);
/**
* vhost_dev_is_started() - report status of vhost device
* @hdev: common vhost_dev structure
*
* Return the started status of the vhost device
*/
static inline bool vhost_dev_is_started(struct vhost_dev *hdev)
{
return hdev->started;
}
/**
* vhost_dev_start() - start the vhost device
* @hdev: common vhost_dev structure
* @vdev: the VirtIODevice structure
*
* Starts the vhost device. From this point VirtIO feature negotiation
* can start and the device can start processing VirtIO transactions.
*
* Return: 0 on success, < 0 on error.
*/
int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev);
/**
* vhost_dev_stop() - stop the vhost device
* @hdev: common vhost_dev structure
* @vdev: the VirtIODevice structure
*
* Stop the vhost device. After the device is stopped the notifiers
* can be disabled (@vhost_dev_disable_notifiers) and the device can
* be torn down (@vhost_dev_cleanup).
*/
void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev);
/**
* DOC: vhost device configuration handling
*
* The VirtIO device configuration space is used for rarely changing
* or initialisation time parameters. The configuration can be updated
* by either the guest driver or the device itself. If the device can
* change the configuration over time the vhost handler should
* register a @VhostDevConfigOps structure with
* @vhost_dev_set_config_notifier so the guest can be notified. Some
* devices register a handler anyway and will signal an error if an
* unexpected config change happens.
*/
/**
* vhost_dev_get_config() - fetch device configuration
* @hdev: common vhost_dev_structure
* @config: pointer to device appropriate config structure
* @config_len: size of device appropriate config structure
*
* Return: 0 on success, < 0 on error while setting errp
*/
int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config,
uint32_t config_len, Error **errp);
/**
* vhost_dev_set_config() - set device configuration
* @hdev: common vhost_dev_structure
* @data: pointer to data to set
* @offset: offset into configuration space
* @size: length of set
* @flags: @VhostSetConfigType flags
*
* By use of @offset/@size a subset of the configuration space can be
* written to. The @flags are used to indicate if it is a normal
* transaction or related to migration.
*
* Return: 0 on success, non-zero on error
*/
int vhost_dev_set_config(struct vhost_dev *dev, const uint8_t *data,
uint32_t offset, uint32_t size, uint32_t flags);
/**
* vhost_dev_set_config_notifier() - register VhostDevConfigOps
* @hdev: common vhost_dev_structure
* @ops: notifier ops
*
* If the device is expected to change configuration a notifier can be
* setup to handle the case.
*/
void vhost_dev_set_config_notifier(struct vhost_dev *dev,
const VhostDevConfigOps *ops);
/* Test and clear masked event pending status.
* Should be called after unmask to avoid losing events.
*/
bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n);
/* Mask/unmask events from this vq.
*/
void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n,
bool mask);
/**
* vhost_get_features() - return a sanitised set of feature bits
* @hdev: common vhost_dev structure
* @feature_bits: pointer to terminated table of feature bits
* @features: original feature set
*
* This returns a set of features bits that is an intersection of what
* is supported by the vhost backend (hdev->features), the supported
* feature_bits and the requested feature set.
*/
uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits,
uint64_t features);
/**
* vhost_ack_features() - set vhost acked_features
* @hdev: common vhost_dev structure
* @feature_bits: pointer to terminated table of feature bits
* @features: requested feature set
*
* This sets the internal hdev->acked_features to the intersection of
* the backends advertised features and the supported feature_bits.
*/
void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits,
uint64_t features);
bool vhost_has_free_slot(void);
int vhost_net_set_backend(struct vhost_dev *hdev,
struct vhost_vring_file *file);
int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write);
void vhost_dev_reset_inflight(struct vhost_inflight *inflight);
void vhost_dev_free_inflight(struct vhost_inflight *inflight);
void vhost_dev_save_inflight(struct vhost_inflight *inflight, QEMUFile *f);
int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f);
int vhost_dev_prepare_inflight(struct vhost_dev *hdev, VirtIODevice *vdev);
int vhost_dev_set_inflight(struct vhost_dev *dev,
struct vhost_inflight *inflight);
int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size,
struct vhost_inflight *inflight);
#endif