/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_VDPA_H
#define _LINUX_VDPA_H
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/vhost_iotlb.h>
/**
* struct vdpa_calllback - vDPA callback definition.
* @callback: interrupt callback function
* @private: the data passed to the callback function
*/
struct vdpa_callback {
irqreturn_t (*callback)(void *data);
void *private;
};
/**
* struct vdpa_notification_area - vDPA notification area
* @addr: base address of the notification area
* @size: size of the notification area
*/
struct vdpa_notification_area {
resource_size_t addr;
resource_size_t size;
};
/**
* struct vdpa_vq_state_split - vDPA split virtqueue state
* @avail_index: available index
*/
struct vdpa_vq_state_split {
u16 avail_index;
};
/**
* struct vdpa_vq_state_packed - vDPA packed virtqueue state
* @last_avail_counter: last driver ring wrap counter observed by device
* @last_avail_idx: device available index
* @last_used_counter: device ring wrap counter
* @last_used_idx: used index
*/
struct vdpa_vq_state_packed {
u16 last_avail_counter:1;
u16 last_avail_idx:15;
u16 last_used_counter:1;
u16 last_used_idx:15;
};
struct vdpa_vq_state {
union {
struct vdpa_vq_state_split split;
struct vdpa_vq_state_packed packed;
};
};
struct vdpa_mgmt_dev;
/**
* struct vdpa_device - representation of a vDPA device
* @dev: underlying device
* @dma_dev: the actual device that is performing DMA
* @config: the configuration ops for this device.
* @index: device index
* @features_valid: were features initialized? for legacy guests
* @nvqs: maximum number of supported virtqueues
* @mdev: management device pointer; caller must setup when registering device as part
* of dev_add() mgmtdev ops callback before invoking _vdpa_register_device().
*/
struct vdpa_device {
struct device dev;
struct device *dma_dev;
const struct vdpa_config_ops *config;
unsigned int index;
bool features_valid;
int nvqs;
struct vdpa_mgmt_dev *mdev;
};
/**
* struct vdpa_iova_range - the IOVA range support by the device
* @first: start of the IOVA range
* @last: end of the IOVA range
*/
struct vdpa_iova_range {
u64 first;
u64 last;
};
/**
* struct vdpa_config_ops - operations for configuring a vDPA device.
* Note: vDPA device drivers are required to implement all of the
* operations unless it is mentioned to be optional in the following
* list.
*
* @set_vq_address: Set the address of virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
* @desc_area: address of desc area
* @driver_area: address of driver area
* @device_area: address of device area
* Returns integer: success (0) or error (< 0)
* @set_vq_num: Set the size of virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
* @num: the size of virtqueue
* @kick_vq: Kick the virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
* @set_vq_cb: Set the interrupt callback function for
* a virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
* @cb: virtio-vdev interrupt callback structure
* @set_vq_ready: Set ready status for a virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
* @ready: ready (true) not ready(false)
* @get_vq_ready: Get ready status for a virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
* Returns boolean: ready (true) or not (false)
* @set_vq_state: Set the state for a virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
* @state: pointer to set virtqueue state (last_avail_idx)
* Returns integer: success (0) or error (< 0)
* @get_vq_state: Get the state for a virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
* @state: pointer to returned state (last_avail_idx)
* @get_vq_notification: Get the notification area for a virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
* Returns the notifcation area
* @get_vq_irq: Get the irq number of a virtqueue (optional,
* but must implemented if require vq irq offloading)
* @vdev: vdpa device
* @idx: virtqueue index
* Returns int: irq number of a virtqueue,
* negative number if no irq assigned.
* @get_vq_align: Get the virtqueue align requirement
* for the device
* @vdev: vdpa device
* Returns virtqueue algin requirement
* @get_features: Get virtio features supported by the device
* @vdev: vdpa device
* Returns the virtio features support by the
* device
* @set_features: Set virtio features supported by the driver
* @vdev: vdpa device
* @features: feature support by the driver
* Returns integer: success (0) or error (< 0)
* @set_config_cb: Set the config interrupt callback
* @vdev: vdpa device
* @cb: virtio-vdev interrupt callback structure
* @get_vq_num_max: Get the max size of virtqueue
* @vdev: vdpa device
* Returns u16: max size of virtqueue
* @get_device_id: Get virtio device id
* @vdev: vdpa device
* Returns u32: virtio device id
* @get_vendor_id: Get id for the vendor that provides this device
* @vdev: vdpa device
* Returns u32: virtio vendor id
* @get_status: Get the device status
* @vdev: vdpa device
* Returns u8: virtio device status
* @set_status: Set the device status
* @vdev: vdpa device
* @status: virtio device status
* @get_config_size: Get the size of the configuration space
* @vdev: vdpa device
* Returns size_t: configuration size
* @get_config: Read from device specific configuration space
* @vdev: vdpa device
* @offset: offset from the beginning of
* configuration space
* @buf: buffer used to read to
* @len: the length to read from
* configuration space
* @set_config: Write to device specific configuration space
* @vdev: vdpa device
* @offset: offset from the beginning of
* configuration space
* @buf: buffer used to write from
* @len: the length to write to
* configuration space
* @get_generation: Get device config generation (optional)
* @vdev: vdpa device
* Returns u32: device generation
* @get_iova_range: Get supported iova range (optional)
* @vdev: vdpa device
* Returns the iova range supported by
* the device.
* @set_map: Set device memory mapping (optional)
* Needed for device that using device
* specific DMA translation (on-chip IOMMU)
* @vdev: vdpa device
* @iotlb: vhost memory mapping to be
* used by the vDPA
* Returns integer: success (0) or error (< 0)
* @dma_map: Map an area of PA to IOVA (optional)
* Needed for device that using device
* specific DMA translation (on-chip IOMMU)
* and preferring incremental map.
* @vdev: vdpa device
* @iova: iova to be mapped
* @size: size of the area
* @pa: physical address for the map
* @perm: device access permission (VHOST_MAP_XX)
* Returns integer: success (0) or error (< 0)
* @dma_unmap: Unmap an area of IOVA (optional but
* must be implemented with dma_map)
* Needed for device that using device
* specific DMA translation (on-chip IOMMU)
* and preferring incremental unmap.
* @vdev: vdpa device
* @iova: iova to be unmapped
* @size: size of the area
* Returns integer: success (0) or error (< 0)
* @free: Free resources that belongs to vDPA (optional)
* @vdev: vdpa device
*/
struct vdpa_config_ops {
/* Virtqueue ops */
int (*set_vq_address)(struct vdpa_device *vdev,
u16 idx, u64 desc_area, u64 driver_area,
u64 device_area);
void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num);
void (*kick_vq)(struct vdpa_device *vdev, u16 idx);
void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx,
struct vdpa_callback *cb);
void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready);
bool (*get_vq_ready)(struct vdpa_device *vdev, u16 idx);
int (*set_vq_state)(struct vdpa_device *vdev, u16 idx,
const struct vdpa_vq_state *state);
int (*get_vq_state)(struct vdpa_device *vdev, u16 idx,
struct vdpa_vq_state *state);
struct vdpa_notification_area
(*get_vq_notification)(struct vdpa_device *vdev, u16 idx);
/* vq irq is not expected to be changed once DRIVER_OK is set */
int (*get_vq_irq)(struct vdpa_device *vdv, u16 idx);
/* Device ops */
u32 (*get_vq_align)(struct vdpa_device *vdev);
u64 (*get_features)(struct vdpa_device *vdev);
int (*set_features)(struct vdpa_device *vdev, u64 features);
void (*set_config_cb)(struct vdpa_device *vdev,
struct vdpa_callback *cb);
u16 (*get_vq_num_max)(struct vdpa_device *vdev);
u32 (*get_device_id)(struct vdpa_device *vdev);
u32 (*get_vendor_id)(struct vdpa_device *vdev);
u8 (*get_status)(struct vdpa_device *vdev);
void (*set_status)(struct vdpa_device *vdev, u8 status);
size_t (*get_config_size)(struct vdpa_device *vdev);
void (*get_config)(struct vdpa_device *vdev, unsigned int offset,
void *buf, unsigned int len);
void (*set_config)(struct vdpa_device *vdev, unsigned int offset,
const void *buf, unsigned int len);
u32 (*get_generation)(struct vdpa_device *vdev);
struct vdpa_iova_range (*get_iova_range)(struct vdpa_device *vdev);
/* DMA ops */
int (*set_map)(struct vdpa_device *vdev, struct vhost_iotlb *iotlb);
int (*dma_map)(struct vdpa_device *vdev, u64 iova, u64 size,
u64 pa, u32 perm);
int (*dma_unmap)(struct vdpa_device *vdev, u64 iova, u64 size);
/* Free device resources */
void (*free)(struct vdpa_device *vdev);
};
struct vdpa_device *__vdpa_alloc_device(struct device *parent,
const struct vdpa_config_ops *config,
size_t size, const char *name);
/**
* vdpa_alloc_device - allocate and initilaize a vDPA device
*
* @dev_struct: the type of the parent structure
* @member: the name of struct vdpa_device within the @dev_struct
* @parent: the parent device
* @config: the bus operations that is supported by this device
* @name: name of the vdpa device
*
* Return allocated data structure or ERR_PTR upon error
*/
#define vdpa_alloc_device(dev_struct, member, parent, config, name) \
container_of(__vdpa_alloc_device( \
parent, config, \
sizeof(dev_struct) + \
BUILD_BUG_ON_ZERO(offsetof( \
dev_struct, member)), name), \
dev_struct, member)
int vdpa_register_device(struct vdpa_device *vdev, int nvqs);
void vdpa_unregister_device(struct vdpa_device *vdev);
int _vdpa_register_device(struct vdpa_device *vdev, int nvqs);
void _vdpa_unregister_device(struct vdpa_device *vdev);
/**
* struct vdpa_driver - operations for a vDPA driver
* @driver: underlying device driver
* @probe: the function to call when a device is found. Returns 0 or -errno.
* @remove: the function to call when a device is removed.
*/
struct vdpa_driver {
struct device_driver driver;
int (*probe)(struct vdpa_device *vdev);
void (*remove)(struct vdpa_device *vdev);
};
#define vdpa_register_driver(drv) \
__vdpa_register_driver(drv, THIS_MODULE)
int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner);
void vdpa_unregister_driver(struct vdpa_driver *drv);
#define module_vdpa_driver(__vdpa_driver) \
module_driver(__vdpa_driver, vdpa_register_driver, \
vdpa_unregister_driver)
static inline struct vdpa_driver *drv_to_vdpa(struct device_driver *driver)
{
return container_of(driver, struct vdpa_driver, driver);
}
static inline struct vdpa_device *dev_to_vdpa(struct device *_dev)
{
return container_of(_dev, struct vdpa_device, dev);
}
static inline void *vdpa_get_drvdata(const struct vdpa_device *vdev)
{
return dev_get_drvdata(&vdev->dev);
}
static inline void vdpa_set_drvdata(struct vdpa_device *vdev, void *data)
{
dev_set_drvdata(&vdev->dev, data);
}
static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev)
{
return vdev->dma_dev;
}
static inline void vdpa_reset(struct vdpa_device *vdev)
{
const struct vdpa_config_ops *ops = vdev->config;
vdev->features_valid = false;
ops->set_status(vdev, 0);
}
static inline int vdpa_set_features(struct vdpa_device *vdev, u64 features)
{
const struct vdpa_config_ops *ops = vdev->config;
vdev->features_valid = true;
return ops->set_features(vdev, features);
}
static inline void vdpa_get_config(struct vdpa_device *vdev, unsigned offset,
void *buf, unsigned int len)
{
const struct vdpa_config_ops *ops = vdev->config;
/*
* Config accesses aren't supposed to trigger before features are set.
* If it does happen we assume a legacy guest.
*/
if (!vdev->features_valid)
vdpa_set_features(vdev, 0);
ops->get_config(vdev, offset, buf, len);
}
/**
* struct vdpa_mgmtdev_ops - vdpa device ops
* @dev_add: Add a vdpa device using alloc and register
* @mdev: parent device to use for device addition
* @name: name of the new vdpa device
* Driver need to add a new device using _vdpa_register_device()
* after fully initializing the vdpa device. Driver must return 0
* on success or appropriate error code.
* @dev_del: Remove a vdpa device using unregister
* @mdev: parent device to use for device removal
* @dev: vdpa device to remove
* Driver need to remove the specified device by calling
* _vdpa_unregister_device().
*/
struct vdpa_mgmtdev_ops {
int (*dev_add)(struct vdpa_mgmt_dev *mdev, const char *name);
void (*dev_del)(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev);
};
struct vdpa_mgmt_dev {
struct device *device;
const struct vdpa_mgmtdev_ops *ops;
const struct virtio_device_id *id_table; /* supported ids */
struct list_head list;
};
int vdpa_mgmtdev_register(struct vdpa_mgmt_dev *mdev);
void vdpa_mgmtdev_unregister(struct vdpa_mgmt_dev *mdev);
#endif /* _LINUX_VDPA_H */
