gem5  v21.1.0.2
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gem5::VirtIOBlock Class Reference

VirtIO block device. More...

#include <block.hh>

Inheritance diagram for gem5::VirtIOBlock:
gem5::VirtIODeviceBase gem5::SimObject gem5::EventManager gem5::Serializable gem5::Drainable gem5::statistics::Group gem5::Named

Classes

struct  BlkRequest
 VirtIO block device request as sent by guest. More...
 
struct  Config
 Block device configuration structure. More...
 
class  RequestQueue
 Virtqueue for disk requests. More...
 

Public Types

typedef VirtIOBlockParams Params
 
- Public Types inherited from gem5::VirtIODeviceBase
typedef uint16_t QueueID
 
typedef uint32_t FeatureBits
 
typedef uint16_t VirtAddress
 This is a VirtQueue address as exposed through the low-level interface. The address needs to be multiplied by the page size (seems to be hardcoded to 4096 in the spec) to get the real physical address. More...
 
typedef uint16_t DeviceId
 Device Type (sometimes known as subsystem ID) More...
 
- Public Types inherited from gem5::SimObject
typedef SimObjectParams Params
 

Public Member Functions

 VirtIOBlock (const Params &params)
 
virtual ~VirtIOBlock ()
 
void readConfig (PacketPtr pkt, Addr cfgOffset)
 Read from the configuration space of a device. More...
 
- Public Member Functions inherited from gem5::VirtIODeviceBase
 BitUnion8 (DeviceStatus) Bitfield< 7 > failed
 
 EndBitUnion (DeviceStatus) typedef VirtIODeviceBaseParams Params
 
 VirtIODeviceBase (const Params &params, DeviceId id, size_t config_size, FeatureBits features)
 
virtual ~VirtIODeviceBase ()
 
void serialize (CheckpointOut &cp) const override
 Serialize an object. More...
 
void unserialize (CheckpointIn &cp) override
 Unserialize an object. More...
 
virtual void writeConfig (PacketPtr pkt, Addr cfgOffset)
 Write to the configuration space of a device. More...
 
virtual void reset ()
 Driver-request device reset. More...
 
void registerKickCallback (const std::function< void()> &callback)
 Register a callback to kick the guest through the transport interface. More...
 
void onNotify (QueueID index)
 Driver is requesting service. More...
 
void setQueueSelect (QueueID idx)
 Change currently active queue. More...
 
QueueID getQueueSelect () const
 Get the currently active queue. More...
 
void setQueueAddress (uint32_t address)
 Change the host physical address of the currently active queue. More...
 
uint32_t getQueueAddress () const
 Get the host physical address of the currently active queue. More...
 
uint16_t getQueueSize () const
 Get the size (descriptors) of the currently active queue. More...
 
void setDeviceStatus (DeviceStatus status)
 Update device status and optionally reset device. More...
 
DeviceStatus getDeviceStatus () const
 Retrieve the device status. More...
 
void setGuestFeatures (FeatureBits features)
 Set feature bits accepted by the guest driver. More...
 
FeatureBits getGuestFeatures () const
 Get features accepted by the guest driver. More...
 
- Public Member Functions inherited from gem5::SimObject
const Paramsparams () const
 
 SimObject (const Params &p)
 
virtual ~SimObject ()
 
virtual void init ()
 init() is called after all C++ SimObjects have been created and all ports are connected. More...
 
virtual void loadState (CheckpointIn &cp)
 loadState() is called on each SimObject when restoring from a checkpoint. More...
 
virtual void initState ()
 initState() is called on each SimObject when not restoring from a checkpoint. More...
 
virtual void regProbePoints ()
 Register probe points for this object. More...
 
virtual void regProbeListeners ()
 Register probe listeners for this object. More...
 
ProbeManagergetProbeManager ()
 Get the probe manager for this object. More...
 
virtual PortgetPort (const std::string &if_name, PortID idx=InvalidPortID)
 Get a port with a given name and index. More...
 
virtual void startup ()
 startup() is the final initialization call before simulation. More...
 
DrainState drain () override
 Provide a default implementation of the drain interface for objects that don't need draining. More...
 
virtual void memWriteback ()
 Write back dirty buffers to memory using functional writes. More...
 
virtual void memInvalidate ()
 Invalidate the contents of memory buffers. More...
 
void serialize (CheckpointOut &cp) const override
 Serialize an object. More...
 
void unserialize (CheckpointIn &cp) override
 Unserialize an object. More...
 
- Public Member Functions inherited from gem5::EventManager
EventQueueeventQueue () const
 
void schedule (Event &event, Tick when)
 
void deschedule (Event &event)
 
void reschedule (Event &event, Tick when, bool always=false)
 
void schedule (Event *event, Tick when)
 
void deschedule (Event *event)
 
void reschedule (Event *event, Tick when, bool always=false)
 
void wakeupEventQueue (Tick when=(Tick) -1)
 This function is not needed by the usual gem5 event loop but may be necessary in derived EventQueues which host gem5 on other schedulers. More...
 
void setCurTick (Tick newVal)
 
 EventManager (EventManager &em)
 Event manger manages events in the event queue. More...
 
 EventManager (EventManager *em)
 
 EventManager (EventQueue *eq)
 
- Public Member Functions inherited from gem5::Serializable
 Serializable ()
 
virtual ~Serializable ()
 
void serializeSection (CheckpointOut &cp, const char *name) const
 Serialize an object into a new section. More...
 
void serializeSection (CheckpointOut &cp, const std::string &name) const
 
void unserializeSection (CheckpointIn &cp, const char *name)
 Unserialize an a child object. More...
 
void unserializeSection (CheckpointIn &cp, const std::string &name)
 
- Public Member Functions inherited from gem5::Drainable
DrainState drainState () const
 Return the current drain state of an object. More...
 
virtual void notifyFork ()
 Notify a child process of a fork. More...
 
- Public Member Functions inherited from gem5::statistics::Group
 Group (Group *parent, const char *name=nullptr)
 Construct a new statistics group. More...
 
virtual ~Group ()
 
virtual void regStats ()
 Callback to set stat parameters. More...
 
virtual void resetStats ()
 Callback to reset stats. More...
 
virtual void preDumpStats ()
 Callback before stats are dumped. More...
 
void addStat (statistics::Info *info)
 Register a stat with this group. More...
 
const std::map< std::string, Group * > & getStatGroups () const
 Get all child groups associated with this object. More...
 
const std::vector< Info * > & getStats () const
 Get all stats associated with this object. More...
 
void addStatGroup (const char *name, Group *block)
 Add a stat block as a child of this block. More...
 
const InforesolveStat (std::string name) const
 Resolve a stat by its name within this group. More...
 
void mergeStatGroup (Group *block)
 Merge the contents (stats & children) of a block to this block. More...
 
 Group ()=delete
 
 Group (const Group &)=delete
 
Groupoperator= (const Group &)=delete
 
- Public Member Functions inherited from gem5::Named
 Named (const std::string &name_)
 
virtual ~Named ()=default
 
virtual std::string name () const
 

Protected Member Functions

Status read (const BlkRequest &req, VirtDescriptor *desc_chain, size_t off_data, size_t size)
 Device read request. More...
 
Status write (const BlkRequest &req, VirtDescriptor *desc_chain, size_t off_data, size_t size)
 Device write request. More...
 
- Protected Member Functions inherited from gem5::VirtIODeviceBase
void kick ()
 Inform the guest of available buffers. More...
 
void registerQueue (VirtQueue &queue)
 Register a new VirtQueue with the device model. More...
 
void readConfigBlob (PacketPtr pkt, Addr cfgOffset, const uint8_t *cfg)
 Read configuration data from a device structure. More...
 
void writeConfigBlob (PacketPtr pkt, Addr cfgOffset, uint8_t *cfg)
 Write configuration data to a device structure. More...
 
- Protected Member Functions inherited from gem5::Drainable
 Drainable ()
 
virtual ~Drainable ()
 
virtual void drainResume ()
 Resume execution after a successful drain. More...
 
void signalDrainDone () const
 Signal that an object is drained. More...
 

Protected Attributes

Config config
 
RequestQueue qRequests
 Device I/O request queue. More...
 
DiskImageimage
 Image backing this device. More...
 
- Protected Attributes inherited from gem5::VirtIODeviceBase
FeatureBits guestFeatures
 Feature set accepted by the guest. More...
 
ByteOrder byteOrder
 The byte order of the queues, descriptors, etc. More...
 
- Protected Attributes inherited from gem5::SimObject
const SimObjectParams & _params
 Cached copy of the object parameters. More...
 
- Protected Attributes inherited from gem5::EventManager
EventQueueeventq
 A pointer to this object's event queue. More...
 

Static Protected Attributes

static const DeviceId ID_BLOCK = 0x02
 
Feature bits
static const FeatureBits F_SIZE_MAX = (1 << 1)
 
static const FeatureBits F_SEG_MAX = (1 << 2)
 
static const FeatureBits F_GEOMETRY = (1 << 4)
 
static const FeatureBits F_RO = (1 << 5)
 
static const FeatureBits F_BLK_SIZE = (1 << 6)
 
static const FeatureBits F_TOPOLOGY = (1 << 10)
 

VirtIO block requests

typedef uint32_t RequestType
 
static const RequestType T_IN = 0
 Read request. More...
 
static const RequestType T_OUT = 1
 Write request. More...
 
static const RequestType T_FLUSH = 4
 Flush device buffers. More...
 

VirtIO block request status

typedef uint8_t Status
 
static const Status S_OK = 0
 Request succeeded. More...
 
static const Status S_IOERR = 1
 Request failed due to a device error. More...
 
static const Status S_UNSUPP = 2
 Request not supported. More...
 

Additional Inherited Members

- Static Public Member Functions inherited from gem5::SimObject
static void serializeAll (const std::string &cpt_dir)
 Create a checkpoint by serializing all SimObjects in the system. More...
 
static SimObjectfind (const char *name)
 Find the SimObject with the given name and return a pointer to it. More...
 
static void setSimObjectResolver (SimObjectResolver *resolver)
 There is a single object name resolver, and it is only set when simulation is restoring from checkpoints. More...
 
static SimObjectResolvergetSimObjectResolver ()
 There is a single object name resolver, and it is only set when simulation is restoring from checkpoints. More...
 
- Static Public Member Functions inherited from gem5::Serializable
static const std::string & currentSection ()
 Gets the fully-qualified name of the active section. More...
 
static void generateCheckpointOut (const std::string &cpt_dir, std::ofstream &outstream)
 Generate a checkpoint file so that the serialization can be routed to it. More...
 
- Public Attributes inherited from gem5::VirtIODeviceBase
Bitfield< 2 > driver_ok
 
Bitfield< 1 > driver
 
Bitfield< 0 > acknowledge
 
const DeviceId deviceId
 Device ID (sometimes known as subsystem ID) More...
 
const size_t configSize
 Size of the device's configuration space. More...
 
const FeatureBits deviceFeatures
 Feature set offered by the device. More...
 

Detailed Description

VirtIO block device.

The block device uses the following queues:

  1. Requests

A guest issues a request by creating a descriptor chain that starts with a BlkRequest. Immediately after the BlkRequest follows the data for the request. The data buffer(s) are either input or output descriptors depending on the request type. The last byte in the descriptor chain should always be writable by the host and contains the request status code (OK/Error).

The protocol supports asynchronous request completion by returning descriptor chains when they have been populated by the backing store. However, there is little point in doing so here.

See also
https://github.com/rustyrussell/virtio-spec
http://docs.oasis-open.org/virtio/virtio/v1.0/virtio-v1.0.html

Definition at line 70 of file block.hh.

Member Typedef Documentation

◆ Params

typedef VirtIOBlockParams gem5::VirtIOBlock::Params

Definition at line 73 of file block.hh.

◆ RequestType

typedef uint32_t gem5::VirtIOBlock::RequestType
protected

Definition at line 108 of file block.hh.

◆ Status

typedef uint8_t gem5::VirtIOBlock::Status
protected

Definition at line 120 of file block.hh.

Constructor & Destructor Documentation

◆ VirtIOBlock()

gem5::VirtIOBlock::VirtIOBlock ( const Params params)

◆ ~VirtIOBlock()

gem5::VirtIOBlock::~VirtIOBlock ( )
virtual

Definition at line 59 of file block.cc.

Member Function Documentation

◆ read()

VirtIOBlock::Status gem5::VirtIOBlock::read ( const BlkRequest req,
VirtDescriptor desc_chain,
size_t  off_data,
size_t  size 
)
protected

Device read request.

Parameters
reqDisk request from guest.
desc_chainRequest descriptor chain (from start of request)
off_dataOffset into the descriptor chain where data should be written.
sizeRequest data size.

Definition at line 73 of file block.cc.

References gem5::VirtDescriptor::chainWrite(), data, DPRINTF, image, gem5::ArmISA::offset, panic, gem5::DiskImage::read(), S_IOERR, S_OK, gem5::VirtIOBlock::BlkRequest::sector, SectorSize, and warn.

Referenced by gem5::VirtIOBlock::RequestQueue::onNotifyDescriptor().

◆ readConfig()

void gem5::VirtIOBlock::readConfig ( PacketPtr  pkt,
Addr  cfgOffset 
)
virtual

Read from the configuration space of a device.

This method is called by the transport interface to read data from a device model's configuration space. The device model should use the cfgOffset parameter as the offset into its configuration space.

Warning
The address in the packet should not be used to determine the offset into a device's configuration space.
Parameters
pktRead request packet.
cfgOffsetOffset into the device's configuration space.

Reimplemented from gem5::VirtIODeviceBase.

Definition at line 64 of file block.cc.

References gem5::VirtIODeviceBase::byteOrder, gem5::VirtIOBlock::Config::capacity, config, gem5::htog(), and gem5::VirtIODeviceBase::readConfigBlob().

◆ write()

VirtIOBlock::Status gem5::VirtIOBlock::write ( const BlkRequest req,
VirtDescriptor desc_chain,
size_t  off_data,
size_t  size 
)
protected

Device write request.

Parameters
reqDisk request from guest.
desc_chainRequest descriptor chain (from start of request)
off_dataOffset into the descriptor chain where data should be read.
sizeRequest data size.

Definition at line 99 of file block.cc.

References gem5::VirtDescriptor::chainRead(), data, DPRINTF, image, gem5::ArmISA::offset, panic, S_IOERR, S_OK, gem5::VirtIOBlock::BlkRequest::sector, SectorSize, warn, and gem5::DiskImage::write().

Referenced by gem5::VirtIOBlock::RequestQueue::onNotifyDescriptor().

Member Data Documentation

◆ config

Config gem5::VirtIOBlock::config
protected

Definition at line 92 of file block.hh.

Referenced by readConfig(), and VirtIOBlock().

◆ F_BLK_SIZE

const FeatureBits gem5::VirtIOBlock::F_BLK_SIZE = (1 << 6)
staticprotected

Definition at line 101 of file block.hh.

◆ F_GEOMETRY

const FeatureBits gem5::VirtIOBlock::F_GEOMETRY = (1 << 4)
staticprotected

Definition at line 99 of file block.hh.

◆ F_RO

const FeatureBits gem5::VirtIOBlock::F_RO = (1 << 5)
staticprotected

Definition at line 100 of file block.hh.

◆ F_SEG_MAX

const FeatureBits gem5::VirtIOBlock::F_SEG_MAX = (1 << 2)
staticprotected

Definition at line 98 of file block.hh.

◆ F_SIZE_MAX

const FeatureBits gem5::VirtIOBlock::F_SIZE_MAX = (1 << 1)
staticprotected

Definition at line 97 of file block.hh.

◆ F_TOPOLOGY

const FeatureBits gem5::VirtIOBlock::F_TOPOLOGY = (1 << 10)
staticprotected

Definition at line 102 of file block.hh.

◆ ID_BLOCK

const DeviceId gem5::VirtIOBlock::ID_BLOCK = 0x02
staticprotected

Definition at line 80 of file block.hh.

◆ image

DiskImage& gem5::VirtIOBlock::image
protected

Image backing this device.

Definition at line 187 of file block.hh.

Referenced by read(), VirtIOBlock(), and write().

◆ qRequests

RequestQueue gem5::VirtIOBlock::qRequests
protected

Device I/O request queue.

Definition at line 184 of file block.hh.

Referenced by VirtIOBlock().

◆ S_IOERR

const Status gem5::VirtIOBlock::S_IOERR = 1
staticprotected

Request failed due to a device error.

Definition at line 124 of file block.hh.

Referenced by read(), and write().

◆ S_OK

const Status gem5::VirtIOBlock::S_OK = 0
staticprotected

Request succeeded.

Definition at line 122 of file block.hh.

Referenced by gem5::VirtIOBlock::RequestQueue::onNotifyDescriptor(), read(), and write().

◆ S_UNSUPP

const Status gem5::VirtIOBlock::S_UNSUPP = 2
staticprotected

Request not supported.

Definition at line 126 of file block.hh.

Referenced by gem5::VirtIOBlock::RequestQueue::onNotifyDescriptor().

◆ T_FLUSH

const RequestType gem5::VirtIOBlock::T_FLUSH = 4
staticprotected

Flush device buffers.

Definition at line 114 of file block.hh.

Referenced by gem5::VirtIOBlock::RequestQueue::onNotifyDescriptor().

◆ T_IN

const RequestType gem5::VirtIOBlock::T_IN = 0
staticprotected

Read request.

Definition at line 110 of file block.hh.

Referenced by gem5::VirtIOBlock::RequestQueue::onNotifyDescriptor().

◆ T_OUT

const RequestType gem5::VirtIOBlock::T_OUT = 1
staticprotected

Write request.

Definition at line 112 of file block.hh.

Referenced by gem5::VirtIOBlock::RequestQueue::onNotifyDescriptor().


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

Generated on Tue Sep 21 2021 12:28:20 for gem5 by doxygen 1.8.17