Struct TChunkCreateInfo

struct TChunkCreateInfo;

Description

This structure specifies the type and properties of the chunk to be created. It is passed as a parameter to the RChunk::Create(TChunkCreateInfo &) method.

Members

Defined in TChunkCreateInfo:

• ESharedKernelMultipleA chunk which may be opened by any number of user side processes.
• ESharedKernelSingleA chunk which may only be opened by one user side process at a time. Chunks of t...
• SetClearByte(TUint8)Sets the byte value that all memory committed to the chunk will be cleared to.
• SetCode(TInt,TInt)Sets the chunk to be create to be user writable and to be marked by the kernel a...
• SetDisconnected(TInt,TInt,TInt)Set the chunk to be created to have a committed region consisting of an arbitrar...
• SetDoubleEnded(TInt,TInt,TInt)Sets the chunk to be created to have a commited region that that can be any cont...
• SetGlobal(const TDesC &)Sets the chunk to be created to be global, i.e. it is potentially visible to all...
• SetNormal(TInt,TInt)Sets the chunk to be created to have a committed region that always starts at th...
• SetOwner(TOwnerType)Sets the owner of the chunk to be created.
• TChunkCreateInfo()Constructor which zeros all member data.
• TChunkCreateInfo()Default constructor.
• TTypeEnumeration representing the type of chunk to be created.
• iDestroyedDfcPointer to a DFC which will be queued on destruction of chunk.
• iMapAttrCaching attributes for the chunks memory.
• iOwnsMemorySet to true if the chunk is to own its committed memory. In which case all memor...
• iTypeThe chunk type to be created.

inline TChunkCreateInfo();

Description

Constructor which zeros all member data.

IMPORT_C TChunkCreateInfo();

Description

Default constructor.

This defaults the chunk to be created to be local, to have no attributes set and to use the default clear byte.

A local chunk is private to the process creating it and is not intended for access by other user processes.

IMPORT_C void SetNormal(TInt aInitialSize, TInt aMaxSize);

Description

Sets the chunk to be created to have a committed region that always starts at the bottom of the reserved region.

Parameters

See also:

• RChunk::CreateLocal(TInt,TInt,TOwnerType)Creates a local chunk.

IMPORT_C void SetCode(TInt aInitialSize, TInt aMaxSize);

Description

Sets the chunk to be create to be user writable and to be marked by the kernel as containing code. This is can only be set on local chunks.

Parameters

See also:

• RChunk::CreateLocalCode(TInt,TInt,TOwnerType)Creates a user writable chunk that is marked by the kernel as containing code.

IMPORT_C void SetDoubleEnded(TInt aInitialBottom, TInt aInitialTop, TInt aMaxSize);

Description

Sets the chunk to be created to have a commited region that that can be any contiguous subset of the reserved region.

Parameters

See also:

• RChunk::CreateDoubleEndedLocal(TInt,TInt,TInt,TOwnerType)Creates a local, double ended, chunk.

IMPORT_C void SetDisconnected(TInt aInitialBottom, TInt aInitialTop, TInt aMaxSize);

Description

Set the chunk to be created to have a committed region consisting of an arbitrary set of MMU pages within the reserved region.

Parameters

See also:

• RChunk::CreateDisconnectedLocal(TInt,TInt,TInt,TOwnerType)Creates a local, disconnected chunk.

IMPORT_C void SetOwner(TOwnerType aType);

Description

Sets the owner of the chunk to be created.

Parameters

IMPORT_C void SetGlobal(const TDesC &aName);

Description

Sets the chunk to be created to be global, i.e. it is potentially visible to all processes and is intended for access by other user processes.

Parameters

IMPORT_C void SetClearByte(TUint8 aClearByte);

Description

Sets the byte value that all memory committed to the chunk will be cleared to.

Parameters

TType

Description

Enumeration representing the type of chunk to be created.

TType iType;

Description

The chunk type to be created.

See also:

• TChunkCreateInfo::TTypeEnumeration representing the type of chunk to be created.

TUint32 iMapAttr;

Description

Caching attributes for the chunks memory.

This is a value constructed from the TMappingAttributes values. E.g. EMapAttrFullyBlocking (no caching) or EMapAttrCachedMax (full caching).

Note that if the MMU doesn't support the requested attributes then a lesser cached attribute will be used. The actual value used is returned in aMapAttr of Kern::ChunkCreate(const TChunkCreateInfo &,DChunk *&,TLinAddr &,TUint32 &)

TUint8 iOwnsMemory;

Description

Set to true if the chunk is to own its committed memory. In which case all memory committed to the chunk will come from the system's free pool and will be returned there when the chunk is destroyed.

TDfc * iDestroyedDfc;

Description

Pointer to a DFC which will be queued on destruction of chunk.