PsReadMmioLinear

Reads MMIO contents using a linear address.

Syntax

PULSE_STATUS PsReadMmioLinear(
 [in] PPS_ENGINE pEngine,
 [in] uint64_t PageTableAddress,
 [in] uint64_t Address,
 [in] uint8_t AccessSize,
 [in, out] PS_CACHE_TYPE *pCacheType,
 [out] void* pBuffer,
 [in] uint64_t cbToRead,
 [out, optional] uint64_t* pcbRead
);

Parameters

PPS_ENGINE pEngine

An opaque handle to an engine created by the EngCreateEngine function.

uint64_t PageTableAddress

The target page table root address. This page table is used to perform the page walk for the given address. The currently loaded page table address is in the CR3 register.

uint64_t Address

The linear address from which to read.

uint8_t AccessSize

The size of the access that will be used for MMIO reads. Valid values are 1, 2, 4 and 8.

PS_CACHE_TYPE *pCacheType

The memory caching type that will be used for MMIO reads. Receives the effective memory-caching type used for the operation. See Remarks for more information.

void* pBuffer

The buffer that stores the read data.

uint64_t cbToRead

Specifies how many bytes should be read.

uint64_t* pcbRead

Returns the number of bytes that were actually read.

Return value

If the function succeeds, the return value is PULSE_STATUS_SUCCESS.

If it fails, it returns one of the PULSE_STATUS values. Possible return codes include, but are not limited to, the following:

PULSE_STATUS_PARTIAL_READ
0x00000001		 Only a portion of memory was read. Check the *pcbRead parameter value to determine how many bytes were read.
PULSE_STATUS_INSUFFICIENT_RESOURCES
0xC0000002		 One of the memory allocations failed during initialization.
PULSE_STATUS_READ_FAILED
0xC0000003		 Transport communication failed during a read operation.
PULSE_STATUS_WRITE_FAILED
0xC0000004		 Transport communication failed during a write operation.
PULSE_STATUS_TIMEOUT
0xC0000007		 Might happen if
  • Transport I/O timed out.
  • No response was received from the debuggee within the request timeout period.
PULSE_STATUS_INVALID_PARAMETER
0xC0000010		 Might happen if
  • The pEngine parameter is NULL.
  • The pBuffer parameter is NULL.
  • The pCacheType parameter is NULL.
  • The offset parameter is not aligned to the AccessSize.
  • The cbToRead parameter is not aligned to the AccessSize.
  • The AccessSize is not equal to 1, 2, 4 or 8.
PULSE_STATUS_INVALID_PACKET
0xC0000031		 An invalid or unexpected packet was received in response.
PULSE_STATUS_INVALID_TRANSLATION
0xC0000021		 Linear to physical address translation failed. Might happen if there is no valid page in the translation.
PULSE_STATUS_DEVICE_CONNECTION_LOST
0xC0000308		 The connection to the transport was lost. Try restarting the engine or the transport.

Remarks

The maximum number of bytes that can be read in a single request can be determined using the PsRequestGetMaxReadMmioLinearBufferSize function. If a larger amount is specified, this function performs multiple requests to the debug target.

Partial reads may occur when address translation is not available beyond a certain point.

The function attempts to use the memory caching type specified by pCacheType, but platform settings may override it. The effective memory caching type used for the operation is returned through pCacheType