我的驱动和程序共享内存代码
网上例子很多，最开始始终找不到为撒共享不起的原因，先总结如下。// NOTE: 如果控制界面还未启动而此时映射到用户空间// 等到控制界面启动时再来获取该映射地址则会出错
// 因为该映射地址所在的进程环境不是控制界面的进程环境
//因此该映射地址对控制界面来说不可用
驱动关键代码：
PMDL Mdl;
PVOID UserVAToReturn;//返回的用户地址
PVOID pSMToResturn;//返回的共享内存地址（内核层）
PHYSICAL_ADDRESSLowAddress; //指示物理地址范围的最小值
PHYSICAL_ADDRESSHighAddress; //指示物理地址范围的最大值
NTSTATUSstatus;
DEVICE_EXTENSION*device_extension;
device_extension = (DEVICE_EXTENSION *)pDeviceObject->DeviceExtension;
//分配内存
if (device_extension->pShareMemory == NULL){
pSMToResturn = ExAllocatePool(NonPagedPool, TotalBytes);
if (!pSMToResturn)
{
KdPrint(("Allocate the memory failed!\n"));
status = STATUS_INSUFFICIENT_RESOURCES;
goto quit_flag;
}
//将内存组织为MDL传递给用户层使用
Mdl = IoAllocateMdl(pSMToResturn, TotalBytes,FALSE,FALSE,NULL);
if (!Mdl)
{
status = STATUS_INSUFFICIENT_RESOURCES;
KdPrint(("Allocate MDL failed\n"));
goto quit_flag;
}
//将MDL描述的物理页面集合映射到系统地址空间
MmBuildMdlForNonPagedPool(Mdl);
}
else{
Mdl = device_extension->pMdl;
pSMToResturn = device_extension->pShareMemory;
}
//映射物理页到虚拟内存地址（用户态）可以被使用
UserVAToReturn = MmMapLockedPagesSpecifyCache(Mdl,UserMode,MmCached,NULL,FALSE,NormalPagePriority);
if (!UserVAToReturn)
{
KdPrint(("Map MDL address failed!\n"));
IoFreeMdl(Mdl);
Mdl = NULL;
ExFreePool(pSMToResturn);
pSMToResturn = NULL;
status = STATUS_INSUFFICIENT_RESOURCES;
goto quit_flag;
}
//返回得到的MDL和用户层虚拟地址
*pShareMemory = pSMToResturn;
*pUserAddress = UserVAToReturn;
*PMemMdl = Mdl;
status = STATUS_SUCCESS;
quit_flag:
return status;
程序关键代码：
//获取驱动的共享内存
if (!DeviceIoControl(Device,IOCTL_FILE_DISK_GET_SHARE_MEMORY,NULL,0,&userVA,sizeof(ULONG_PTR),&retBytes,NULL
))
{
sprintf_s(log_msg, sizeof(log_msg), "Get the share memory failed [%d]", GetLastError());
cout<<log_msg<<endl;
cout<<"read:"<<retBytes<<endl;
return -1;
}
pShareMemory = (SHARE_MEMORY *)userVA;
页:
[1]