Commit Graph

4 Commits

Author SHA1 Message Date
Bill Paul
63ba67b69c - Correct one aspect of the driver_object/device_object/IRP framework:
when we create a PDO, the driver_object associated with it is that
  of the parent driver, not the driver we're trying to attach. For
  example, if we attach a PCI device, the PDO we pass to the NdisAddDevice()
  function should contain a pointer to fake_pci_driver, not to the NDIS
  driver itself. For PCI or PCMCIA devices this doesn't matter because
  the child never needs to talk to the parent bus driver, but for USB,
  the child needs to be able to send IRPs to the parent USB bus driver, and
  for that to work the parent USB bus driver has to be hung off the PDO.

  This involves modifying windrv_lookup() so that we can search for
  bus drivers by name, if necessary. Our fake bus drivers attach themselves
  as "PCI Bus," "PCCARD Bus" and "USB Bus," so we can search for them
  using those names.

  The individual attachment stubs now create and attach PDOs to the
  parent bus drivers instead of hanging them off the NDIS driver's
  object, and in if_ndis.c, we now search for the correct driver
  object depending on the bus type, and use that to find the correct PDO.

  With this fix, I can get my sample USB ethernet driver to deliver
  an IRP to my fake parent USB bus driver's dispatch routines.

- Add stub modules for USB support: subr_usbd.c, usbd_var.h and
  if_ndis_usb.c. The subr_usbd.c module is hooked up the build
  but currently doesn't do very much. It provides the stub USB
  parent driver object and a dispatch routine for
  IRM_MJ_INTERNAL_DEVICE_CONTROL. The only exported function at
  the moment is USBD_GetUSBDIVersion(). The if_ndis_usb.c stub
  compiles, but is not hooked up to the build yet. I'm putting
  these here so I can keep them under source code control as I
  flesh them out.
2005-02-24 21:49:14 +00:00
Bill Paul
513c5292f8 Fix freeing of custom driver extensions. (ExFreePool() was being
called with the wrong pointer.)
2005-02-16 19:21:07 +00:00
Bill Paul
d8f2dda739 Add support for Windows/x86-64 binaries to Project Evil.
Ville-Pertti Keinonen (will at exomi dot comohmygodnospampleasekthx)
deserves a big thanks for submitting initial patches to make it
work. I have mangled his contributions appropriately.

The main gotcha with Windows/x86-64 is that Microsoft uses a different
calling convention than everyone else. The standard ABI requires using
6 registers for argument passing, with other arguments on the stack.
Microsoft uses only 4 registers, and requires the caller to leave room
on the stack for the register arguments incase the callee needs to
spill them. Unlike x86, where Microsoft uses a mix of _cdecl, _stdcall
and _fastcall, all routines on Windows/x86-64 uses the same convention.
This unfortunately means that all the functions we export to the
driver require an intermediate translation wrapper. Similarly, we have
to wrap all calls back into the driver binary itself.

The original patches provided macros to wrap every single routine at
compile time, providing a secondary jump table with a customized
wrapper for each exported routine. I decided to use a different approach:
the call wrapper for each function is created from a template at
runtime, and the routine to jump to is patched into the wrapper as
it is created. The subr_pe module has been modified to patch in the
wrapped function instead of the original. (On x86, the wrapping
routine is a no-op.)

There are some minor API differences that had to be accounted for:

- KeAcquireSpinLock() is a real function on amd64, not a macro wrapper
  around KfAcquireSpinLock()
- NdisFreeBuffer() is actually IoFreeMdl(). I had to change the whole
  NDIS_BUFFER API a bit to accomodate this.

Bugs fixed along the way:
- IoAllocateMdl() always returned NULL
- kern_windrv.c:windrv_unload() wasn't releasing private driver object
  extensions correctly (found thanks to memguard)

This has only been tested with the driver for the Broadcom 802.11g
chipset, which was the only Windows/x86-64 driver I could find.
2005-02-16 05:41:18 +00:00
Bill Paul
b545a3b822 Next step on the road to IRPs: create and use an imitation of the
Windows DRIVER_OBJECT and DEVICE_OBJECT mechanism so that we can
simulate driver stacking.

In Windows, each loaded driver image is attached to a DRIVER_OBJECT
structure. Windows uses the registry to match up a given vendor/device
ID combination with a corresponding DRIVER_OBJECT. When a driver image
is first loaded, its DriverEntry() routine is invoked, which sets up
the AddDevice() function pointer in the DRIVER_OBJECT and creates
a dispatch table (based on IRP major codes). When a Windows bus driver
detects a new device, it creates a Physical Device Object (PDO) for
it. This is a DEVICE_OBJECT structure, with semantics analagous to
that of a device_t in FreeBSD. The Windows PNP manager will invoke
the driver's AddDevice() function and pass it pointers to the DRIVER_OBJECT
and the PDO.

The AddDevice() function then creates a new DRIVER_OBJECT structure of
its own. This is known as the Functional Device Object (FDO) and
corresponds roughly to a private softc instance. The driver uses
IoAttachDeviceToDeviceStack() to add this device object to the
driver stack for this PDO. Subsequent drivers (called filter drivers
in Windows-speak) can be loaded which add themselves to the stack.
When someone issues an IRP to a device, it travel along the stack
passing through several possible filter drivers until it reaches
the functional driver (which actually knows how to talk to the hardware)
at which point it will be completed. This is how Windows achieves
driver layering.

Project Evil now simulates most of this. if_ndis now has a modevent
handler which will use MOD_LOAD and MOD_UNLOAD events to drive the
creation and destruction of DRIVER_OBJECTs. (The load event also
does the relocation/dynalinking of the image.) We don't have a registry,
so the DRIVER_OBJECTS are stored in a linked list for now. Eventually,
the list entry will contain the vendor/device ID list extracted from
the .INF file. When ndis_probe() is called and detectes a supported
device, it will create a PDO for the device instance and attach it
to the DRIVER_OBJECT just as in Windows. ndis_attach() will then call
our NdisAddDevice() handler to create the FDO. The NDIS miniport block
is now a device extension hung off the FDO, just as it is in Windows.
The miniport characteristics table is now an extension hung off the
DRIVER_OBJECT as well (the characteristics are the same for all devices
handled by a given driver, so they don't need to be per-instance.)
We also do an IoAttachDeviceToDeviceStack() to put the FDO on the
stack for the PDO. There are a couple of fake bus drivers created
for the PCI and pccard buses. Eventually, there will be one for USB,
which will actually accept USB IRP.s

Things should still work just as before, only now we do things in
the proper order and maintain the correct framework to support passing
IRPs between drivers.

Various changes:

- corrected the comments about IRQL handling in subr_hal.c to more
  accurately reflect reality
- update ndiscvt to make the drv_data symbol in ndis_driver_data.h a
  global so that if_ndis_pci.o and/or if_ndis_pccard.o can see it.
- Obtain the softc pointer from the miniport block by referencing
  the PDO rather than a private pointer of our own (nmb_ifp is no
  longer used)
- implement IoAttachDeviceToDeviceStack(), IoDetachDevice(),
  IoGetAttachedDevice(), IoAllocateDriverObjectExtension(),
  IoGetDriverObjectExtension(), IoCreateDevice(), IoDeleteDevice(),
  IoAllocateIrp(), IoReuseIrp(), IoMakeAssociatedIrp(), IoFreeIrp(),
  IoInitializeIrp()
- fix a few mistakes in the driver_object and device_object definitions
- add a new module, kern_windrv.c, to handle the driver registration
  and relocation/dynalinkign duties (which don't really belong in
  kern_ndis.c).
- made ndis_block and ndis_chars in the ndis_softc stucture pointers
  and modified all references to it
- fixed NdisMRegisterMiniport() and NdisInitializeWrapper() so they
  work correctly with the new driver_object mechanism
- changed ndis_attach() to call NdisAddDevice() instead of ndis_load_driver()
  (which is now deprecated)
- used ExAllocatePoolWithTag()/ExFreePool() in lookaside list routines
  instead of kludged up alloc/free routines
- added kern_windrv.c to sys/modules/ndis/Makefile and files.i386.
2005-02-08 17:23:25 +00:00