guest_xfer

Flags for the state read and write requests

Synopsis:

#include <qvm/guest.h>

enum guest_xfer_flags {
    GXF_NONE = 0x00000000,
    GXF_PAUSE = 0x00000001,
    GXF_UNPAUSE = 0x00000002,
    GXF_ASYNC = 0x00000004,
    GXF_GDB = 0x00000008,
    GXF_FLUSH = 0x00000010
};

Data:

GXF_NONE: No flag is set.
GXF_PAUSE: Pause the CPU before the transaction.
GXF_UNPAUSE: Unpause the CPU after the transaction.
GXF_ASYNC: The transaction may be performed asynchronously. Use with caution.
GXF_GDB: For internal use only.
GXF_FLUSH: Flush the data cache after an operation.

Description:

The default read and write states flag setting is GXF_NONE. Use the other values with caution. For example, if you specify GXF_PAUSE and GXF_UNPAUSE, the target CPU is paused before the transaction and resumed after the transaction, which impacts performance.

If you specify GXF_ASYNC, however, the transaction is performed without pausing the CPU. Asynchronous transactions have less impact on performance than transactions that pause the target CPU. However, inappropriate use of asynchronous transactions may lead to undefined behavior.

If you aren't sure about how to use these flags, contact your QNX representative.