Device_Io.allocatebuffer() - Intel Extensible Firmware Interface Specification

6.2.5

DEVICE_IO.AllocateBuffer()

Summary
Allocates pages that are suitable for an
Prototype
typedef
EFI_STATUS
(EFIAPI *EFI_IO_ALLOCATE_BUFFER) (
IN EFI_DEVICE_IO_INTERFACE
IN EFI_ALLOCATE_TYPE
IN EFI_MEMORY_TYPE
IN UINTN
IN OUT EFI_PHYSICAL_ADDRESS
);
Parameters
This
Type
MemoryType
Pages
HostAddress
Description
The
AllocateBuffer()
EFIBusMasterCommonBuffer
The
AllocateBuffer()
range that can be mapped as an EFIBusMasterCommonBuffer. When the buffer is no longer
needed, the driver frees the memory with a call to FreeBuffer().
Allocation requests of
satisfies the request. On input the data pointed to by
Version 1.02
EFIBusMasterCommonBuffer
A pointer to the EFI_DEVICE_IO_INTERFACE. Type
EFI_DEVICE_IO_INTERFACE
The type allocation to perform. Type
defined in Chapter 3.
The type of memory to allocate,
EfiRuntimeServicesData. Type
in Chapter 3.
The number of pages to allocate.
A pointer to store the base address of the allocated range. Type
PHYSICAL_ADDRESS
function allocates pages that are suitable for an
mapping.
function internally calls
Type AllocateAnyPages
*This,
Type,
MemoryType,
Pages,
*HostAddress
is defined in Section 6.2.
EFI_ALLOCATE_TYPE
EfiBootServicesData
EFI_MEMORY_TYPE
is defined in Chapter 3.
AllocatePages()
will allocate any available range of pages that
is ignored.
HostAddress
12/12/00
Device I/O Protocol
mapping.
is
or
is defined
EFI_
to allocate a memory
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