IPC interface for virtio over L4 IPC. More...

#include <l4virtio>

Inheritance diagram for L4virtio::Device:

Collaboration diagram for L4virtio::Device:

Public Member Functions
long	set_status (unsigned status)
	Write the VIRTIO status register.

long	config_queue (unsigned queue)
	Trigger queue configuration of the given queue.

long	register_ds (L4::Ipc::Cap< L4Re::Dataspace > ds_cap, l4_uint64_t base, l4_umword_t offset, l4_umword_t size)
	Register a shared data space with VIRTIO host.

long	device_config (L4::Ipc::Out< L4::Cap< L4Re::Dataspace > > config_ds, l4_addr_t *ds_offset)
	Get the dataspace with the L4virtio configuration page.

long	device_notification_irq (unsigned index, L4::Ipc::Out< L4::Cap< L4::Triggerable > > irq)
	Get the notification interrupt corresponding to the given index.

Public Member Functions inherited from L4::Icu
l4_msgtag_t	bind (unsigned irqnum, L4::Cap< Triggerable > irq, l4_utcb_t *utcb=l4_utcb()) noexcept
	Bind an interrupt line of an interrupt controller to an interrupt object.

l4_msgtag_t	unbind (unsigned irqnum, L4::Cap< Triggerable > irq, l4_utcb_t *utcb=l4_utcb()) noexcept
	Remove binding of an interrupt line from the interrupt controller object.

l4_msgtag_t	info (l4_icu_info_t info, l4_utcb_t utcb=l4_utcb()) noexcept
	Get information about the ICU features.

l4_msgtag_t	msi_info (l4_umword_t irqnum, l4_uint64_t source, l4_icu_msi_info_t *msi_info)
	Get MSI info about IRQ.

l4_msgtag_t	mask (unsigned irqnum, l4_umword_t label=0, l4_timeout_t to=L4_IPC_NEVER, l4_utcb_t utcb=l4_utcb()) noexcept
	Mask an IRQ line.

l4_msgtag_t	set_mode (unsigned irqnum, l4_umword_t mode, l4_utcb_t *utcb=l4_utcb()) noexcept
	Set interrupt mode.

Public Member Functions inherited from L4::Irq_eoi
l4_msgtag_t	unmask (unsigned irqnum, l4_umword_t label=0, l4_timeout_t to=L4_IPC_NEVER, l4_utcb_t utcb=l4_utcb()) noexcept
	Unmask the given interrupt line.

Additional Inherited Members
Protected Types inherited from L4::Kobject_t< Device, L4::Icu, L4VIRTIO_PROTOCOL, L4::Type_info::Demand_t< 1 > >
typedef Device	Class
	The target interface type (inheriting from Kobject_t)

typedef Typeid::Iface< PROTO, Device >	__Iface
	The interface description for the derived class.

typedef Typeid::Merge_list< Typeid::Iface_list< __Iface >, typename Base::__Iface_list >	__Iface_list
	The list of all RPC interfaces provided directly or through inheritance.

Protected Types inherited from L4::Kobject_t< Icu, Irq_eoi, L4_PROTO_IRQ, Type_info::Demand_t< 1 > >
typedef Icu	Class
	The target interface type (inheriting from Kobject_t)

typedef Typeid::Iface< PROTO, Icu >	__Iface
	The interface description for the derived class.

typedef Typeid::Merge_list< Typeid::Iface_list< __Iface >, typename Base::__Iface_list >	__Iface_list
	The list of all RPC interfaces provided directly or through inheritance.

Protected Member Functions inherited from L4::Kobject_t< Device, L4::Icu, L4VIRTIO_PROTOCOL, L4::Type_info::Demand_t< 1 > >
L4::Cap< Class >	c () const noexcept
	Get the capability to ourselves.

Protected Member Functions inherited from L4::Kobject_t< Icu, Irq_eoi, L4_PROTO_IRQ, Type_info::Demand_t< 1 > >
L4::Cap< Class >	c () const noexcept
	Get the capability to ourselves.

Static Protected Member Functions inherited from L4::Kobject_t< Device, L4::Icu, L4VIRTIO_PROTOCOL, L4::Type_info::Demand_t< 1 > >
static void	__check_protocols__ () noexcept
	Helper to check for protocol conflicts.

Static Protected Member Functions inherited from L4::Kobject_t< Icu, Irq_eoi, L4_PROTO_IRQ, Type_info::Demand_t< 1 > >
static void	__check_protocols__ () noexcept
	Helper to check for protocol conflicts.

Detailed Description

IPC interface for virtio over L4 IPC.

The L4virtio protocol is an adaption of the mmio virtio transport 1.0(4). This interface allows to exchange the necessary resources: device configuration page, notification interrupts and dataspaces for payload.

Notification interrupts can be configured independently for changes to the configuration space and each queue through special L4virtio-specific notify_index fields in the config page and queue configuration. The interface distinguishes between device-to-driver and driver-to-device notification interrupts.

Device-to-driver interrupts are configured via the ICU interface. The device announces the maximum number of supported interrupts via Icu::info(). The driver can then bind interrupts using Icu::bind().

Driver-to-device interrupts must be requested from the device through device_notification_irq().

Definition at line 39 of file l4virtio.

Member Function Documentation

◆ config_queue()

long L4virtio::Device::config_queue ( unsigned queue )

Trigger queue configuration of the given queue.

Usually all queues are configured when the status is written to running. However, in some cases queues shall be disabled or enabled dynamically, in this case this function triggers a reconfiguration from the shared memory register of the queue config.

Parameters

queue Queue index for the queue to be configured.

Return values

0	on success.
-L4_EIO	The queue's status is invalid.
-L4_ERANGE	The queue index exceeds the number of queues.
-L4_EINVAL	Otherwise.

Referenced by L4virtio::Driver::Device::config_queue().

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◆ device_config()

long L4virtio::Device::device_config	(	L4::Ipc::Out< L4::Cap< L4Re::Dataspace > >	config_ds,
		l4_addr_t *	ds_offset
	)

Get the dataspace with the L4virtio configuration page.

Parameters

config_ds	Capability for receiving the dataspace capability for the shared L4-VIRTIO config data space.
ds_offset	Offset into the dataspace where the device configuration structure starts.

Referenced by L4virtio::Driver::Device::driver_connect().

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◆ device_notification_irq()

long L4virtio::Device::device_notification_irq	(	unsigned	index,
		L4::Ipc::Out< L4::Cap< L4::Triggerable > >	irq
	)

Get the notification interrupt corresponding to the given index.

Parameters

	index	Index of the interrupt.
[out]	irq	Triggerable for the given index.

Return values

L4_EOK	Success.
L4_ENOSYS	IRQ notification not supported by device.
<0	Other error.

An index is only guaranteed to return an IRQ object when the index is set in one of the device notify index fields. The device must return the same interrupt for a given index as long as the index is in use. If an index disappears as a result of a configuration change and then is reused later, the interrupt is not guaranteed to be the same.

Interrupts must always be rerequested after a device reset.

Referenced by L4virtio::Driver::Device::driver_connect().

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◆ register_ds()

long L4virtio::Device::register_ds	(	L4::Ipc::Cap< L4Re::Dataspace >	ds_cap,
		l4_uint64_t	base,
		l4_umword_t	offset,
		l4_umword_t	size
	)

Register a shared data space with VIRTIO host.

Parameters

ds_cap	Dataspace capability to register. The lower 8 bits determine the rights mask with which the guest's rights are masked during the registration of the dataspace at the VIRTIO host.
base	VIRTIO guest physical start address of shared memory region
offset	Offset within the data space that is attached to the given `base` in the guest physical memory.
size	Size of the memory region in the guest

Return values

L4_EOK	Operation successful.
-L4_EINVAL	The `ds_cap` capability is invalid, does not refer to a valid dataspace, is not a trusted dataspace if trusted dataspace validation is enabled, or `size` and `offset` specify an invalid region.
-L4_ENOMEM	The limit of dataspaces that can be registered has been reached or no capability slot could be allocated.
-L4_ERANGE	`offset` is lager than the size of the dataspace.
<0	Any error returned by the dataspace when queried for information during setup or any error returned by the region manager from attaching the dataspace.

Referenced by L4virtio::Driver::Device::register_ds().

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◆ set_status()

long L4virtio::Device::set_status ( unsigned status )

Write the VIRTIO status register.

Parameters

status Status word to write to the VIRTIO status.

Return values

0	on success.

Note: All other registers are accessed via shared memory.

Referenced by L4virtio::Driver::Device::driver_acknowledge(), and L4virtio::Driver::Device::driver_connect().

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The documentation for this class was generated from the following file:

l4/l4virtio/l4virtio

Public Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ config_queue()

◆ device_config()

◆ device_notification_irq()

◆ register_ds()

◆ set_status()