that describe a buffer of variable size). The problem is, allocating
MDLs off the heap is slow, and it can happen that drivers will allocate
lots and lots of lots of MDLs as they run.
As a compromise, we now do the following: we pre-allocate a zone for
MDLs big enough to describe any buffer with 16 or less pages. If
IoAllocateMdl() needs a MDL for a buffer with 16 or less pages, we'll
allocate it from the zone. Otherwise, we allocate it from the heap.
MDLs allocate from the zone have a flag set in their mdl_flags field.
When the MDL is released, IoMdlFree() will uma_zfree() the MDL if
it has the MDL_ZONE_ALLOCED flag set, otherwise it will release it
to the heap.
The assumption is that 16 pages is a "big number" and we will rarely
need MDLs larger than that.
- Moved the ndis_buffer zone to subr_ntoskrnl.c from kern_ndis.c
and named it mdl_zone.
- Modified IoAllocateMdl() and IoFreeMdl() to use uma_zalloc() and
uma_zfree() if necessary.
- Made ndis_mtop() use IoAllocateMdl() instead of calling uma_zalloc()
directly.
Inspired by: discussion with Giridhar Pemmasani
o change the mapping arrays to have a zero offset rather than base 1;
this eliminates lots of signo adjustments and brings the code
back inline with the original netbsd code
o purge use of SVR4_SIGTBLZ; SVR4_NSIG is the only definition for
how big a mapping array is
o change the mapping loops to explicitly ignore signal 0
o purge some bogus code from bsd_to_svr4_sigset
o adjust svr4_sysentvec to deal with the mapping table change
Enticed into fixing by: Coverity Prevent analysis tool
Glanced at by: marcel, jhb
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.
right for certain MAP_FIXED mappings on ia64 but it will work fine for all
other mappings and works fine on amd64.
Requested by: ps, Christian Zander
MFC after: 1 week
- In kern_ndis.c:ndis_unload_driver(), test that ndis_block->nmb_rlist
is not NULL before trying to free() it.
- In subr_pe.c:pe_get_import_descriptor(), do a case-insensitive
match on the import module name. Most drivers I have encountered
link against "ntoskrnl.exe" but the ASIX USB ethernet driver I'm
testing with wants "NTOSKRNL.EXE."
- In subr_ntoskrnl.c:IoAllocateIrp(), return a pointer to the IRP
instead of NULL. (Stub code leftover.)
- Also in subr_ntoskrnl.c, add ExAllocatePoolWithTag() and ExFreePool()
to the function table list so they'll get exported to drivers properly.
and a machine-independent though inefficient InterlockedExchange().
In Windows, InterlockedExchange() appears to be implemented in header
files via inline assembly. I would prefer using an atomic.h macro for
this, but there doesn't seem to be one that just does a plain old
atomic exchange (as opposed to compare and exchange). Also implement
IoSetCancelRoutine(), which is just a macro that uses InterlockedExchange().
Fill in IoBuildSynchronousFsdRequest(), IoBuildAsynchronousFsdRequest()
and IoBuildDeviceIoControlRequest() so that they do something useful,
and add a bunch of #defines to ntoskrnl_var.h to help make these work.
These may require some tweaks later.
The fundamental problem is that we get only the lower 8 bits of the
minor device number so there is no guarantee that we can actually
find the disk device in question at all.
This was probably a bigger issue pre-GEOM where the upper bits
signaled which slice were in use.
The secondary problem is how we get from (partial) dev_t to vnode.
The correct implementation will involve traversing the mount list
looking for a perfect match or a possible match (for truncated
minor).
pointers in argv and envv in userland and use that together with
kern_execve() and exec_free_args() to implement freebsd32_execve()
without using the stackgap.
- Fix freebsd32_adjtime() to call adjtime() rather than utimes(). Still
uses stackgap for now.
- Use kern_setitimer(), kern_getitimer(), kern_select(), kern_utimes(),
kern_statfs(), kern_fstatfs(), kern_fhstatfs(), kern_stat(),
kern_fstat(), and kern_lstat().
Tested by: cokane (amd64)
Silence on: amd64, ia64
copy op to shift arguments on the stack instead of transfering each
argument one by one through a register. Probably doesn't affect overall
operation, but makes the code a little less grotty and easier to update
later if I choose to make the wrapper handle more args. Also add
comments.
for now) exactly the same as KfAcquireSpinLock() and KfReleaseSpinLock().
I implemented the former as small routines in subr_ntoskrnl.c that just
turned around and invoked the latter. But I don't really need the wrapper
routines: I can just create an entries in the ntoskrnl func table that
map KeAcquireSpinLockRaiseToDpc() and KeReleaseSpinLock() to
KfAcquireSpinLock() and KfReleaseSpinLock() directly. This means
the stubs can go away.
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.
former is callable from user space and the latter from the kernel one. Make
kernel version take additional argument which tells if the respective call
should check for additional restrictions for sending signals to suid/sugid
applications or not.
Make all emulation layers using non-checked version, since signal numbers in
emulation layers can have different meaning that in native mode and such
protection can cause misbehaviour.
As a result remove LIBTHR from the signals allowed to be delivered to a
suid/sugid application.
Requested (sorta) by: rwatson
MFC after: 2 weeks
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.
the semantics in that the returned filename to use is now a kernel
pointer rather than a user space pointer. This required changing the
arguments to the CHECKALT*() macros some and changing the various system
calls that used pathnames to use the kern_foo() functions that can accept
kernel space filename pointers instead of calling the system call
directly.
- Use kern_open(), kern_access(), kern_msgctl(), kern_execve(),
kern_mkfifo(), kern_mknod(), kern_statfs(), kern_fstatfs(),
kern_setitimer(), kern_stat(), kern_lstat(), kern_fstat(), kern_utimes(),
kern_pathconf(), and kern_unlink().
duplicating the contents of the same functions inline.
- Consolidate common code to convert a BSD statfs struct to a Linux struct
into a static worker function.
structure in the struct pointed to by the 3rd argument for IPC_STAT and
get rid of the 4th argument. The old way returned a pointer into the
kernel array that the calling function would then access afterwards
without holding the appropriate locks and doing non-lock-safe things like
copyout() with the data anyways. This change removes that unsafeness and
resulting race conditions as well as simplifying the interface.
- Implement kern_foo wrappers for stat(), lstat(), fstat(), statfs(),
fstatfs(), and fhstatfs(). Use these wrappers to cut out a lot of
code duplication for freebsd4 and netbsd compatability system calls.
- Add a new lookup function kern_alternate_path() that looks up a filename
under an alternate prefix and determines which filename should be used.
This is basically a more general version of linux_emul_convpath() that
can be shared by all the ABIs thus allowing for further reduction of
code duplication.
providing special version of CDIOCREADSUBCHANNEL ioctl(), which assumes that
result has to be placed into kernel space not user space. In the long run
more generic solution has to be designed WRT emulating various ioctl()s
that operate on userspace buffers, but right now there is only one such
ioctl() is emulated, so that it makes little sense.
MFC after: 2 weeks
copies arguments into the kernel space and one that operates
completely in the kernel space;
o use kernel-only version of execve(2) to kill another stackgap in
linuxlator/i386.
Obtained from: DragonFlyBSD (partially)
MFC after: 2 weeks
from the userland and pushes results back and the second which does
actual processing. Use the latter to eliminate stackgap in the linux wrapper
of that syscall.
MFC after: 2 weeks
pops data from the userland and pushes results back and the second which does
actual processing. Use the latter to eliminate stackgap in the linux wrappers
of those syscalls.
MFC after: 2 weeks
attributes in casts (i.e. foo = (__stdcall sometype)bar). This only
happens in two places where we need to set up function pointers, so
work around the problem with some void pointer magic.
USB device support):
- Convert all of my locally chosen function names to their actual
Windows equivalents, where applicable. This is a big no-op change
since it doesn't affect functionality, but it helps avoid a bit
of confusion (it's now a lot easier to see which functions are
emulated Windows API routines and which are just locally defined).
- Turn ndis_buffer into an mdl, like it should have been. The structure
is the same, but now it belongs to the subr_ntoskrnl module.
- Implement a bunch of MDL handling macros from Windows and use them where
applicable.
- Correct the implementation of IoFreeMdl().
- Properly implement IoAllocateMdl() and MmBuildMdlForNonPagedPool().
- Add the definitions for struct irp and struct driver_object.
- Add IMPORT_FUNC() and IMPORT_FUNC_MAP() macros to make formatting
the module function tables a little cleaner. (Should also help
with AMD64 support later on.)
- Fix if_ndis.c to use KeRaiseIrql() and KeLowerIrql() instead of
the previous calls to hal_raise_irql() and hal_lower_irql() which
have been renamed.
The function renaming generated a lot of churn here, but there should
be very little operational effect.
calls MiniportQueryInformation(), it will return NDIS_STATUS_PENDING.
When this happens, ndis_get_info() will sleep waiting for a completion
event. If two threads call ndis_get_info() and both end up having to
sleep, they will both end up waiting on the same wait channel, which
can cause a panic in sleepq_add() if INVARIANTS are turned on.
Fix this by having ndis_get_info() use a common mutex rather than
using the process mutex with PROC_LOCK(). Also do the same for
ndis_set_info(). Note that Pierre's original patch also made ndis_thsuspend()
use the new mutex, but ndis_thsuspend() shouldn't need this since
it will make each thread that calls it sleep on a unique wait channel.
Also, it occured to me that we probably don't want to enter
MiniportQueryInformation() or MiniportSetInformation() from more
than one thread at any given time, so now we acquire a Windows
spinlock before calling either of them. The Microsoft documentation
says that MiniportQueryInformation() and MiniportSetInformation()
are called at DISPATCH_LEVEL, and previously we would call
KeRaiseIrql() to set the IRQL to DISPATCH_LEVEL before entering
either routine, but this only guarantees mutual exclusion on
uniprocessor machines. To make it SMP safe, we need to use a real
spinlock. For now, I'm abusing the spinlock embedded in the
NDIS_MINIPORT_BLOCK structure for this purpose. (This may need to be
applied to some of the other routines in kern_ndis.c at a later date.)
Export ntoskrnl_init_lock() (KeInitializeSpinlock()) from subr_ntoskrnl.c
since we need to use in in kern_ndis.c, and since it's technically part
of the Windows kernel DDK API along with the other spinlock routines. Use
it in subr_ndis.c too rather than frobbing the spinlock directly.
- Mark mount, unmount and nmount MPSAFE.
- Add a stub for _umtx_op().
- Mark open(), link(), unlink(), and freebsd32_sigaction() MPSAFE.
Pointy hats to: several
