v8::PageAllocator Class Reference

#include <v8-platform.h>

Inheritance diagram for v8::PageAllocator:

Public Types
enum	Permission {   kNoAccess, kRead, kReadWrite, kReadWriteExecute,   kReadExecute }

Public Member Functions
virtual size_t	AllocatePageSize ()=0
virtual size_t	CommitPageSize ()=0
virtual void	SetRandomMmapSeed (int64_t seed)=0
virtual void *	GetRandomMmapAddr ()=0
virtual void *	AllocatePages (void *address, size_t length, size_t alignment, Permission permissions)=0
virtual bool	FreePages (void *address, size_t length)=0
virtual bool	ReleasePages (void *address, size_t length, size_t new_length)=0
virtual bool	SetPermissions (void *address, size_t length, Permission permissions)=0
virtual bool	DiscardSystemPages (void *address, size_t size)

Detailed Description

A V8 memory page allocator.

Can be implemented by an embedder to manage large host OS allocations.

Definition at line 191 of file v8-platform.h.

Member Enumeration Documentation

Permission

enum v8::PageAllocator::Permission

Memory permissions.

Definition at line 222 of file v8-platform.h.

Member Function Documentation

AllocatePages()

virtual void* v8::PageAllocator::AllocatePages ( void *  address, size_t  length, size_t  alignment, Permission  permissions  )

pure virtual

Allocates memory in range with the given alignment and permission.

Implemented in v8::base::BoundedPageAllocator.

AllocatePageSize()

virtual size_t v8::PageAllocator::AllocatePageSize ( )

pure virtual

Gets the page granularity for AllocatePages and FreePages. Addresses and lengths for those calls should be multiples of AllocatePageSize().

Implemented in v8::base::BoundedPageAllocator.

CommitPageSize()

virtual size_t v8::PageAllocator::CommitPageSize ( )

pure virtual

Gets the page granularity for SetPermissions and ReleasePages. Addresses and lengths for those calls should be multiples of CommitPageSize().

Implemented in v8::base::BoundedPageAllocator.

DiscardSystemPages()

virtual bool v8::PageAllocator::DiscardSystemPages ( void *  address, size_t  size  )

inlinevirtual

Frees memory in the given [address, address + size) range. address and size should be operating system page-aligned. The next write to this memory area brings the memory transparently back.

Reimplemented in v8::base::BoundedPageAllocator.

Definition at line 259 of file v8-platform.h.

FreePages()

virtual bool v8::PageAllocator::FreePages ( void *  address, size_t  length  )

pure virtual

Frees memory in a range that was allocated by a call to AllocatePages.

Implemented in v8::base::BoundedPageAllocator.

GetRandomMmapAddr()

virtual void* v8::PageAllocator::GetRandomMmapAddr ( )

pure virtual

Returns a randomized address, suitable for memory allocation under ASLR. The address will be aligned to AllocatePageSize.

Implemented in v8::base::BoundedPageAllocator.

ReleasePages()

virtual bool v8::PageAllocator::ReleasePages ( void *  address, size_t  length, size_t  new_length  )

pure virtual

Releases memory in a range that was allocated by a call to AllocatePages.

Implemented in v8::base::BoundedPageAllocator.

SetPermissions()

virtual bool v8::PageAllocator::SetPermissions ( void *  address, size_t  length, Permission  permissions  )

pure virtual

Sets permissions on pages in an allocated range.

Implemented in v8::base::BoundedPageAllocator.

SetRandomMmapSeed()

virtual void v8::PageAllocator::SetRandomMmapSeed ( int64_t  seed )

pure virtual

Sets the random seed so that GetRandomMmapAddr() will generate repeatable sequences of random mmap addresses.

Implemented in v8::base::BoundedPageAllocator.

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

• v8/include/v8-platform.h