Using section/view in the driver
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From: Gary Li on 30 Sep 2006 20:09 Can I call ZwCreateSection() and ZwMapViewOfSection() with the same handle in the different processes ? -Gary
From: soviet_bloke on 30 Sep 2006 23:29 > Can I call ZwCreateSection() and ZwMapViewOfSection() with the same handle in > the different processes ? Of course you cannot do it - *ANY* handle is valid only in the context of a process that has opened it, unless it has been duplicated with DuplicateHandle() Anton Bassov Gary Li wrote: > Can I call ZwCreateSection() and ZwMapViewOfSection() with the same handle in > the different processes ? > > -Gary
From: Gary Li on 30 Sep 2006 23:46 Thanks for the feeback. My problem actually is: I need to access a big file in the workitem routine (kernel thread created by driver and running in the PASSIVE_LEVEL). However, ZwCreateSection() will report STATUS_SECTION_TOO_BIG if called in the routines other than DriverEntry() or AddDevice(). Therefore, I am planing to create the file and section in AddDevice(), and to map the view in the workitem routines. Now sure whether they are legal. NtCurrentProcess() will be used to get process handle during mapping the view. If AddDevice() and workitem are in different processes, how to use this mechanism ? or is there any other mechanism to try for the same purpose ? Thanks -Gary "soviet_bloke(a)hotmail.com" wrote: > > Can I call ZwCreateSection() and ZwMapViewOfSection() with the same handle in > > the different processes ? > > Of course you cannot do it - *ANY* handle is valid only in the context > of a process that has opened it, unless it has been duplicated with > DuplicateHandle() > > Anton Bassov > > Gary Li wrote: > > Can I call ZwCreateSection() and ZwMapViewOfSection() with the same handle in > > the different processes ? > > > > -Gary > >
From: Gary Li on 1 Oct 2006 00:20 Accroding to DDK, the workitems are in system thread context, which should be in the same process of AddDevice(). Does it mean the workitem can use the section handle created in AddDevice() to map the view. Otherwise, ZwOpenSection() may have to be be used to get the handle. "Gary Li" wrote: > Thanks for the feeback. > > My problem actually is: > I need to access a big file in the workitem routine (kernel thread created > by driver and running in the PASSIVE_LEVEL). However, ZwCreateSection() will > report STATUS_SECTION_TOO_BIG if called in the routines other than > DriverEntry() or AddDevice(). > Therefore, I am planing to create the file and section in AddDevice(), and > to map the view in the workitem routines. Now sure whether they are legal. > NtCurrentProcess() will be used to get process handle during mapping the view. > If AddDevice() and workitem are in different processes, how to use this > mechanism ? or is there any other mechanism to try for the same purpose ? > > Thanks > > -Gary > > "soviet_bloke(a)hotmail.com" wrote: > > > > Can I call ZwCreateSection() and ZwMapViewOfSection() with the same handle in > > > the different processes ? > > > > Of course you cannot do it - *ANY* handle is valid only in the context > > of a process that has opened it, unless it has been duplicated with > > DuplicateHandle() > > > > Anton Bassov > > > > Gary Li wrote: > > > Can I call ZwCreateSection() and ZwMapViewOfSection() with the same handle in > > > the different processes ? > > > > > > -Gary > > > >
From: David J. Craig on 1 Oct 2006 00:48
Which WorkItems? Your own? If so, it is easy. Just open the file in the work item initialization code before the worker thread begins its loop waiting on new items to process. You can use a special 'work item' to let your system thread know that it should exit. OSR has some nice code from a NT Insider several years ago. It uses its own worker thread(s) to process work items because during NT4 the number of system worker threads was limited and generally reserved for file systems. "Gary Li" <garyli(a)verizon.net> wrote in message news:33F28EC5-3D38-4788-A634-E0FEF0B26F40(a)microsoft.com... > Accroding to DDK, the workitems are in system thread context, which should > be > in the same process of AddDevice(). > Does it mean the workitem can use the section handle created in > AddDevice() > to map the view. Otherwise, ZwOpenSection() may have to be be used to get > the > handle. > > "Gary Li" wrote: > >> Thanks for the feeback. >> >> My problem actually is: >> I need to access a big file in the workitem routine (kernel thread >> created >> by driver and running in the PASSIVE_LEVEL). However, ZwCreateSection() >> will >> report STATUS_SECTION_TOO_BIG if called in the routines other than >> DriverEntry() or AddDevice(). >> Therefore, I am planing to create the file and section in AddDevice(), >> and >> to map the view in the workitem routines. Now sure whether they are >> legal. >> NtCurrentProcess() will be used to get process handle during mapping the >> view. >> If AddDevice() and workitem are in different processes, how to use this >> mechanism ? or is there any other mechanism to try for the same purpose ? >> >> Thanks >> >> -Gary >> >> "soviet_bloke(a)hotmail.com" wrote: >> >> > > Can I call ZwCreateSection() and ZwMapViewOfSection() with the same >> > > handle in >> > > the different processes ? >> > >> > Of course you cannot do it - *ANY* handle is valid only in the context >> > of a process that has opened it, unless it has been duplicated with >> > DuplicateHandle() >> > >> > Anton Bassov >> > >> > Gary Li wrote: >> > > Can I call ZwCreateSection() and ZwMapViewOfSection() with the same >> > > handle in >> > > the different processes ? >> > > >> > > -Gary >> > >> > |