gem5  v20.1.0.0
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VirtIO9PBase Class Referenceabstract

This class implements a VirtIO transport layer for the 9p network file system. More...

#include <fs9p.hh>

Inheritance diagram for VirtIO9PBase:
VirtIODeviceBase SimObject EventManager Serializable Drainable Stats::Group VirtIO9PProxy VirtIO9PDiod VirtIO9PSocket

Classes

struct  Config
 VirtIO 9p configuration structure. More...
 
class  FSQueue
 Virtqueue for 9p requests. More...
 

Public Types

typedef VirtIO9PBaseParams Params
 
- Public Types inherited from 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 SimObject
typedef SimObjectParams Params
 

Public Member Functions

 VirtIO9PBase (Params *params)
 
virtual ~VirtIO9PBase ()
 
void readConfig (PacketPtr pkt, Addr cfgOffset)
 Read from the configuration space of a device. More...
 
- Public Member Functions inherited from VirtIODeviceBase
 BitUnion8 (DeviceStatus) Bitfield< 7 > failed
 
 EndBitUnion (DeviceStatus) typedef VirtIODeviceBaseParams Params
 
 VirtIODeviceBase (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 SimObject
const Paramsparams () const
 
 SimObject (const Params *_params)
 
virtual ~SimObject ()
 
virtual const std::string name () const
 
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 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 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 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 Stats::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 (Stats::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...
 
 Group ()=delete
 
 Group (const Group &)=delete
 
Groupoperator= (const Group &)=delete
 

Protected Member Functions

virtual void recvTMsg (const P9MsgHeader &header, const uint8_t *data, size_t size)=0
 Handle incoming 9p RPC message. More...
 
void sendRMsg (const P9MsgHeader &header, const uint8_t *data, size_t size)
 Send a 9p RPC message reply. More...
 
void dumpMsg (const P9MsgHeader &header, const uint8_t *data, size_t size)
 Dump a 9p RPC message on the debug output. More...
 
- Protected Member Functions inherited from 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 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

struct VirtIO9PBase::Config M5_ATTR_PACKED
 
std::unique_ptr< Configconfig
 Currently active configuration (host byte order) More...
 
FSQueue queue
 
- Protected Attributes inherited from 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 SimObject
const SimObjectParams * _params
 Cached copy of the object parameters. More...
 
- Protected Attributes inherited from EventManager
EventQueueeventq
 A pointer to this object's event queue. More...
 

Static Protected Attributes

static const DeviceId ID_9P = 0x09
 VirtIO device ID. More...
 
Feature bits
static const FeatureBits F_MOUNT_TAG = 0x01
 Device provides a name of the resource in its configuration. More...
 

Private Attributes

std::map< P9Tag, VirtDescriptor * > pendingTransactions
 Map between 9p transaction tags and descriptors where they appeared. More...
 

Additional Inherited Members

- Static Public Member Functions inherited from SimObject
static void serializeAll (CheckpointOut &cp)
 Serialize 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 Public Member Functions inherited from Serializable
static const std::string & currentSection ()
 Gets the fully-qualified name of the active section. More...
 
static void serializeAll (const std::string &cpt_dir)
 Serializes all the SimObjects. More...
 
static void unserializeGlobals (CheckpointIn &cp)
 
- Public Attributes inherited from 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

This class implements a VirtIO transport layer for the 9p network file system.

The 9p VirtIO transport uses the following queues:

  1. 9p requests and replies

Each 9p request and response is sent in its own descriptor chain. The guest initiates a transaction by packing a T message (see the 9p spec) into the first part of a descriptor chain. After the T message, the guest reserves space for the reply (R message) by including one or more writable descriptors. The server replies by writing an R message into the writable descriptors and putting the chain in the used ring (VirtQueue::produceDescriptor()).

See also
https://github.com/rustyrussell/virtio-spec
https://github.com/ericvh/9p-rfc
https://code.google.com/p/diod/wiki/protocol

Definition at line 107 of file fs9p.hh.

Member Typedef Documentation

◆ Params

typedef VirtIO9PBaseParams VirtIO9PBase::Params

Definition at line 110 of file fs9p.hh.

Constructor & Destructor Documentation

◆ VirtIO9PBase()

VirtIO9PBase::VirtIO9PBase ( Params params)

◆ ~VirtIO9PBase()

VirtIO9PBase::~VirtIO9PBase ( )
virtual

Definition at line 130 of file fs9p.cc.

Member Function Documentation

◆ dumpMsg()

void VirtIO9PBase::dumpMsg ( const P9MsgHeader header,
const uint8_t *  data,
size_t  size 
)
protected

Dump a 9p RPC message on the debug output.

Parameters
header9p message header.
dataPointer to data in message.
sizeSize of data (excluding header)

Definition at line 192 of file fs9p.cc.

References data, DDUMP, DPRINTF, DTRACE, header, P9MsgInfo::name, and p9_msg_info.

Referenced by VirtIO9PBase::FSQueue::onNotifyDescriptor(), and sendRMsg().

◆ readConfig()

void VirtIO9PBase::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 VirtIODeviceBase.

Definition at line 135 of file fs9p.cc.

References config, and VirtIODeviceBase::readConfigBlob().

◆ recvTMsg()

virtual void VirtIO9PBase::recvTMsg ( const P9MsgHeader header,
const uint8_t *  data,
size_t  size 
)
protectedpure virtual

Handle incoming 9p RPC message.

Parameters
header9p message header.
dataPointer to data in message.
sizeSize of data (excluding header)

Implemented in VirtIO9PProxy.

Referenced by VirtIO9PBase::FSQueue::onNotifyDescriptor().

◆ sendRMsg()

void VirtIO9PBase::sendRMsg ( const P9MsgHeader header,
const uint8_t *  data,
size_t  size 
)
protected

Send a 9p RPC message reply.

Parameters
header9p message header.
dataPointer to data in message.
sizeSize of data (excluding header)

Definition at line 164 of file fs9p.cc.

References VirtDescriptor::chainWrite(), data, DPRINTF, dumpMsg(), header, htop9(), VirtDescriptor::isOutgoing(), VirtIODeviceBase::kick(), P9MsgHeader::len, VirtDescriptor::next(), panic, pendingTransactions, VirtQueue::produceDescriptor(), and queue.

Referenced by VirtIO9PProxy::serverDataReady().

Member Data Documentation

◆ config

std::unique_ptr<Config> VirtIO9PBase::config
protected

Currently active configuration (host byte order)

Definition at line 129 of file fs9p.hh.

Referenced by readConfig(), and VirtIO9PBase().

◆ F_MOUNT_TAG

const FeatureBits VirtIO9PBase::F_MOUNT_TAG = 0x01
staticprotected

Device provides a name of the resource in its configuration.

Definition at line 138 of file fs9p.hh.

◆ ID_9P

const DeviceId VirtIO9PBase::ID_9P = 0x09
staticprotected

VirtIO device ID.

Definition at line 132 of file fs9p.hh.

◆ M5_ATTR_PACKED

struct VirtIO9PBase::Config VirtIO9PBase::M5_ATTR_PACKED
protected

◆ pendingTransactions

std::map<P9Tag, VirtDescriptor *> VirtIO9PBase::pendingTransactions
private

Map between 9p transaction tags and descriptors where they appeared.

When handling asynchronous requests, we need to ensure that replies are posted in the same descriptor as queries. The 9p RPC protocol uses the tag field in the header to match requests and replies, which we use here to find the relevant descriptor.

Definition at line 200 of file fs9p.hh.

Referenced by VirtIO9PBase::FSQueue::onNotifyDescriptor(), and sendRMsg().

◆ queue

FSQueue VirtIO9PBase::queue
protected

Definition at line 161 of file fs9p.hh.

Referenced by sendRMsg(), and VirtIO9PBase().


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

Generated on Wed Sep 30 2020 14:02:34 for gem5 by doxygen 1.8.17