- protect td->td_proc->p_pid with the proc lock in linux_getpid
in the amd64 (= non i386) case [1]
Sponsored by: Google SoC 2006
Submitted by: rdivacky
Noticed by: netchild [1]
has in its procfs (do a readlink of /proc/self/fd/<nn> to find the pathname
that corresponds to a given file descriptor). Valgrind-3.x needs this
functionality. This is a placeholder only at this time.
- Send the systrace_args files for all the compat ABIs to /dev/null for
now. Right now makesyscalls.sh generates a file with a hardcoded
function name, so it wouldn't work for any of the ABIs anyway. Probably
the function name should be configurable via a 'systracename' variable
and the functions should be stored in a function pointer in the sysvec
structure.
- TLS - complete
- pid/tid mangling - complete
- thread area - complete
- futexes - complete with issues
- clone() extension - complete with some possible minor issues
- mq*/timer*/clock* stuff - complete but untested and the mq* stuff is
disabled when not build as part of the kernel with native FreeBSD mq*
support (module support for this will come later)
Tested with:
- linux-firefox - works, tested
- linux-opera - works, tested
- linux-realplay - doesnt work, issue with futexes
- linux-skype - doesnt work, issue with futexes
- linux-rt2-demo - works, tested
- linux-acroread - doesnt work, unknown reason (coredump) and sometimes
issue with futexes
- various unix utilities in linux-base-gentoo3 and linux-base-fc4:
everything tried worked
On amd64 not everything is supported like on i386, the catchup is planned for
later when the remaining bugs in the new functions are fixed.
To test this new stuff, you have to run
sysctl compat.linux.osrelease=2.6.16
to switch back use
sysctl compat.linux.osrelease=2.4.2
Don't switch while running a linux program, strange things may or may not
happen.
Sponsored by: Google SoC 2006
Submitted by: rdivacky
Some suggestions/help by: jhb, kib, manu@NetBSD.org, netchild
Please don't style(9) the NetBSD code, we want to stay in sync. Not imported
on a vendor branch since we need local changes.
Sponsored by: Google SoC 2006
Submitted by: rdivacky
With help from: manu@NetBSD.org
Obtained from: NetBSD (linux_{futex,time}.*)
and vn_fullpath (that call malloc(..., M_WAITOK)) from under the
vm object lock, since sleep is not allowed while holding the mutex.
Being there, wrap VOP_GETATTR call with conditional Giant aquire.
Currently this is (almost) noop because pseudofs is Giant-locked.
Tested by: kris
Approved by: pjd (mentor)
MFC after: 2 weeks
mark system calls as being MPSAFE:
- Stop conditionally acquiring Giant around system call invocations.
- Remove all of the 'M' prefixes from the master system call files.
- Remove support for the 'M' prefix from the script that generates the
syscall-related files from the master system call files.
- Don't explicitly set SYF_MPSAFE when registering nfssvc.
except for s_family (which is read-only once after it is set when the
structure is created).
- Mark svr4_sys_ioctl(), svr4_sys_getmsg(), and svr4_sys_putmsg() MPSAFE.
kern_accept() and accept1(). If another thread closed the new file
descriptor and the first thread later got an error trying to copyout the
socket address, then it would attempt to close the wrong file object. To
fix, add a struct file ** argument to kern_accept(). If it is non-NULL,
then on success kern_accept() will store a pointer to the new file object
there and not release any of the references. It is up to the calling code
to drop the references appropriately (including a call to fdclose() in case
of error to safely handle the aforementioned race). While I'm at it, go
ahead and fix the svr4 streams code to not leak the accept fd if it gets an
error trying to copyout the streams structures.
locked.
- Move all the svr4 socket cache code into svr4_socket.c, specifically
move svr4_delete_socket() over from streams.c. Make the socket cache
entry structure and svr4_head private to svr4_socket.c as a result.
- Add a mutex to protect the svr4 socket cache.
- Change svr4_find_socket() to copy the sockaddr_un struct into a
caller-supplied sockaddr_un rather than giving the caller a pointer to
our internal one. This removes the one case where code outside of
svr4_socket.c could access data in the cache.
- Add an eventhandler for process_exit and process_exec to purge the cache
of any entries for the exiting or execing process.
- Add methods to init and destroy the socket cache and call them from the
svr4 ABI module's event handler.
- Conditionally grab Giant around socreate() in streamsopen().
- Use fdclose() instead of inlining it in streamsopen() when handling
socreate() failure.
- Only allocate a stream structure and attach it to a socket in
streamsopen(). Previously, if a svr4 program performed a stream
operation on an arbitrary socket not opened via the streams device,
we would attach streams state data to it and change f_ops of the
associated struct file while it was in use. The latter was especially
not safe, and if a program wants a stream object it should open it via
the streams device anyway.
- Don't bother locking so_emuldata in the streams code now that we only
touch it right after creating a socket (in streamsopen()) or when
tearing it down when the file is closed.
- Remove D_NEEDGIANT from the streams device as it is no longer needed.
Also, call change_dir() instead of doing part of it inline (this now adds
a mac_check_vnode_chdir() call) to match fchdir() and call
mac_check_vnode_chroot() to match chroot(). Also, use the change_root()
function to do the actual change root to match chroot().
Reviewed by: rwatson
Giant VFS locking in that function.
- Remove bogus code to handle the case where namei() returns success but a
NULL vnode pointer.
- Note that this code duplicates exec_check_permissions() and annotate
where it differs.
- Hold the vnode lock longer to protect the write to set VV_TEXT in
v_vflag.
- Mark linux_uselib() MPSAFE.
Reviewed by: rwatson
- If the WNOWAIT flag isn't specified and either of WEXITED or WTRAPPED is
set, then just call kern_wait() and let it do all the work. This means
that this function no longer has to duplicate the work to teardown
zombies that is done in kern_wait(). Instead, if the above conditions
aren't true, then it uses a simpler loop to implement WNOWAIT and/or
tracing for only stopped or continued processes. This function still
has to duplicate code from kern_wait() for the latter two cases, but
those are much simpler.
- Sync the code to handle the WCONTINUED and WSTOPPED cases with the
equivalent code in kern_wait().
- Fix several places that would return with the proctree lock still held.
- Lock the current process to prevent lost wakeup races when blocking.
ibcs2_getdents(), ibcs2_read(), ogetdirentries(), svr4_sys_getdents(),
and svr4_sys_getdents64() similar to that in getdirentries().
- Mark ibcs2_getdents(), ibcs2_read(), linux_getdents(), linux_getdents64(),
linux_readdir(), ogetdirentries(), svr4_sys_getdents(), and
svr4_sys_getdents64() MPSAFE.
use by ABI emulators.
- Alter the interface of kern_recvit() somewhat. Specifically, go ahead
and hard code UIO_USERSPACE in the uio as that's what all the callers
specify. In place, add a new uioseg to indicate what type of pointer
is in mp->msg_name. Previously it was always a userland address, but
ABI emulators may pass in kernel-side sockaddrs. Also, remove the
namelenp field and instead require the two places that used it to
explicitly copy mp->msg_namelen out to userland.
- Use the patched kern_recvit() to replace svr4_recvit() and the stock
kern_sendit() to replace svr4_sendit().
- Use kern_bind() instead of stackgap use in ti_bind().
- Use kern_getpeername() and kern_getsockname() instead of stackgap in
svr4_stream_ti_ioctl().
- Use kern_connect() instead of stackgap in svr4_do_putmsg().
- Use kern_getpeername() and kern_accept() instead of stackgap in
svr4_do_getmsg().
- Retire the stackgap from SVR4 compat as it is no longer used.
mostly consists of pushing a few copyin's and copyout's up into
__semctl() as all the other callers were already doing the UIO_SYSSPACE
case. This also changes kern_semctl() to set the return value in a passed
in pointer to a register_t rather than td->td_retval[0] directly so that
callers can only set td->td_retval[0] if all the various copyout's succeed.
As a result of these changes, kern_semctl() no longer does copyin/copyout
(except for GETALL/SETALL) so simplify the locking to acquire the semakptr
mutex before the MAC check and hold it all the way until the end of the
big switch statement. The GETALL/SETALL cases have to temporarily drop it
while they do copyin/malloc and copyout. Also, simplify the SETALL case to
remove handling for a non-existent race condition.
shmctl(). None of the other ABI's do this (including the native FreeBSD
ABI), and uselessly trying to do a copyin() can actually result in a
bogus EFAULT if the a process specifies NULL for the optional argument
(which is what they should do in this case).
- process state (idle, sleeping, running, ...) [1]
- the process group ID of the process which owns the connected tty
- some page fault stats
- time spend in kernel/userland
- priority/nice value
- starttime [1]
- memory/swap stats
- scheduling policy
Additionally add some new fields and correct some not filled out ones.
This brings us down to 15 dummy fields.
The fields marked with [1] are needed to get Oracle 10 running. The starttime
field is not completely right, since it displays the _same_ starttime for
_every_ process, but at least it is not 0 and Oracle accepts this.
This is a RELENG_x_y candidate.
Noticed by: Dmitry Ganenko <dima@apk-inform.com> [1]
Reviewed by: des, rdivacky
MFC after: 1 week
to a copied-in copy of the 'union semun' and a uioseg to indicate which
memory space the 'buf' pointer of the union points to. This is then used
in linux_semctl() and svr4_sys_semctl() to eliminate use of the stackgap.
- Mark linux_ipc() and svr4_sys_semsys() MPSAFE.
from going away. mount(2) is now MPSAFE.
- Expand the scope of Giant some in unmount(2) to protect the mp structure
(or rather, to handle concurrent unmount races) from going away.
umount(2) is now MPSAFE, as well as linux_umount() and linux_oldumount().
- nmount(2) and linux_mount() were already MPSAFE.
and don't panic.
This fix is different from the patch submitted as it not only prevents
a NULL-pointer dereference, but also skips some work in this case.
Noticed by: Dmitry Ganenko <dima@apk-inform.com>
Reviewed by: rdivacky (the original version as in emulation@)
MFC after: 1 week
Security: This is a RELENG_x_y candidate (local DoS).
Go ahead by: secteam (cperciva)
file objects calling a user-specified predicate function on each object.
The iteration terminates either when the entire list has been iterated
over or the predicate function returns a non-zero value.
linker_file_foreach() returns the value returned by the last invocation
of the predicate function. It also accepts a void * context pointer that
is passed to the predicate function as well. Using an iterator function
avoids exposing linker internals to the rest of the kernel making locking
simpler.
- Use linker_file_foreach() instead of walking the list of linker files
manually to lookup ndis files in ndis(4).
- Use linker_file_foreach() to implement linker_hwpmc_list_objects().
Add back in a scheme to emulate old type major/minor numbers via hooks into
stat, linprocfs to return major/minors that Linux app's expect. Currently
only /dev/null is always registered. Drivers can register via the Linux
type shim similar to the ioctl shim but by using
linux_device_register_handler/linux_device_unregister_handler functions.
The structure is:
struct linux_device_handler {
char *bsd_driver_name;
char *linux_driver_name;
char *bsd_device_name;
char *linux_device_name;
int linux_major;
int linux_minor;
int linux_char_device;
};
Linprocfs uses this to display the major number of the driver. The
soon to be available linsysfs will use it to fill in the driver name.
Linux_stat uses it to translate the major/minor into Linux type values.
Note major numbers are dynamically assigned via passing in a -1 for
the major number so we don't need to keep track of them.
This is somewhat needed due to us switching to our devfs. MegaCli
will not run until I add in the linsysfs and mfi Linux compat changes.
Sponsored by: IronPort Systems
- rename some file local structure definitions, the names clash with
autogenerated names
- on !alpha add some compatibility defines for those renamed structures
- make some functions globally visible on alpha
the callers if the exec either succeeds or fails early.
- Move the code to call exit1() if the exec fails after the vmspace is
gone to the bottom of kern_execve() to cut down on some code duplication.
linux_ioctl.[ch] : Implement LINUX_TIOCGPTN, which returns the pty number
linux_stats.c :
- Return the magic number for devfs.
- In various stats()-related functions, check that we're stating a
file in /dev/pts, and if so, change the st_rdev field to match what linux
expects to be there for a slave pty device. The glibc checks for this, and
their openpty() fails if it is no correct.
went away in the generated files? This didn't happen on my amd64
test machine but did when I committed it on my other i386 machine.
I need to figure this out since a regen on the amd64 doesn't fix it
now. For now make the build work again. Matt caught this before
my local mirror caught up.
with flags bitfield and set BI_CAN_EXEC_DYN flag for all brands that usually
allow executing elf dynamic binaries (aka shared libraries). When it is
requested to execute ET_DYN elf image check if this flag is on after we
know the elf brand allowing execution if so.
PR: kern/87615
Submitted by: Marcin Koziej <creep@desk.pl>
which existed to cleanup the linux_osname mutex. Now that MTX_SYSINIT()
has grown a SYSUNINIT to destroy mutexes on unload, the extra destroy here
was redundant and resulted in panics in debug kernels.
MFC after: 1 week
Reported by: Goran Gajic ggajic at afrodita dot rcub dot bg dot ac dot yu
they are passed by reference. Handle the difference within the
linux_ioctl_termio on the LINUX_TCFLSH path.
Submitted by: Jaroslav Drzik <jaro_AT_coop-voz_dot_sk>
for a Windows ISR is 'BOOLEAN isrfunc(KINTERRUPT *, void *)' meaning
the ISR get a pointer to the interrupt object and a context pointer,
and returns TRUE if the ISR determines the interrupt was really generated
by the associated device, or FALSE if not.
I had mistakenly used 'void isrfunc(void *)' instead. It happens the
only thing this affects is the internal ndis_intr() ISR in subr_ndis.c,
but it should be fixed just in case we ever need to register a real
Windows ISR vi IoConnectInterrupt().
For NDIS miniports that provide a MiniportISR() method, the 'is_our_intr'
value returned by the method serves as the return value from ndis_isr(),
and 'call_isr' is used to decide whether or not to schedule the interrupt
handler via DPC. For drivers that only supply MiniportEnableInterrupt()
and MiniportDisableInterrupt() methods, call_isr is always TRUE and
is_our_intr is always FALSE.
In the end, there should be no functional changes, except that now
ntoskrnl_intr() can terminate early once it finds the ISR that wants
to service the interrupt.
rather than in ifindex_table[]; all (except one) accesses are
through ifp anyway. IF_LLADDR() works faster, and all (except
one) ifaddr_byindex() users were converted to use ifp->if_addr.
- Stop storing a (pointer to) Ethernet address in "struct arpcom",
and drop the IFP2ENADDR() macro; all users have been converted
to use IF_LLADDR() instead.
Intel's web site requires some minor tweaks to get it to work:
- The driver seems to have been released with full WMI tracing enabled,
and makes references to some WMI APIs, namely IoWMIRegistrationControl(),
WmiQueryTraceInformation() and WmiTraceMessage(). Only the first
one is ever called (during intialization). These have been implemented
as do-nothing stubs for now. Also added a definition for STATUS_NOT_FOUND
to ntoskrnl_var.h, which is used as a return code for one of the WMI
routines.
- The driver references KeRaiseIrqlToDpcLevel() and KeLowerIrql()
(the latter as a function, which is unusual because normally
KeLowerIrql() is a macro in the Windows DDK that calls KfLowewIrql()).
I'm not sure why these are being called since they're not really
part of WDM. Presumeably they're being used for backwards
compatibility with old versions of Windows. These have been
implemented in subr_hal.c. (Note that they're _stdcall routines
instead of _fastcall.)
- When querying the OID_802_11_BSSID_LIST OID to get a BSSID list,
you don't know ahead of time how many networks the NIC has found
during scanning, so you're allowed to pass 0 as the list length.
This should cause the driver to return an 'insufficient resources'
error and set the length to indicate how many bytes are actually
needed. However for some reason, the Intel driver does not honor
this convention: if you give it a length of 0, it returns some
other error and doesn't tell you how much space is really needed.
To get around this, if using a length of 0 yields anything besides
the expected error case, we arbitrarily assume a length of 64K.
This is similar to the hack that wpa_supplicant uses when doing
a BSSID list query.
for code to start out on one CPU when thunking into Windows
mode in ctxsw_utow(), and then be pre-empted and migrated to another
CPU before thunking back to UNIX mode in ctxsw_wtou(). This is
bad, because then we can end up looking at the wrong 'thread environment
block' when trying to come back to UNIX mode. To avoid this, we now
pin ourselves to the current CPU when thunking into Windows code.
Few other cleanups, since I'm here:
- Get rid of the ndis_isr(), ndis_enable_interrupt() and
ndis_disable_interrupt() wrappers from kern_ndis.c and just invoke
the miniport's methods directly in the interrupt handling routines
in subr_ndis.c. We may as well lose the function call overhead,
since we don't need to export these things outside of ndis.ko
now anyway.
- Remove call to ndis_enable_interrupt() from ndis_init() in if_ndis.c.
We don't need to do it there anyway (the miniport init routine handles
it, if needed).
- Fix the logic in NdisWriteErrorLogEntry() a little.
- Change some NDIS_STATUS_xxx codes in subr_ntoskrnl.c into STATUS_xxx
codes.
- Handle kthread_create() failure correctly in PsCreateSystemThread().
Having an additional MT_HEADER mbuf type is superfluous and redundant
as nothing depends on it. It only adds a layer of confusion. The
distinction between header mbuf's and data mbuf's is solely done
through the m->m_flags M_PKTHDR flag.
Non-native code is not changed in this commit. For compatibility
MT_HEADER is mapped to MT_DATA.
Sponsored by: TCP/IP Optimization Fundraise 2005
the start of the section headers has to take into account the fact
that the image_nt_header is really variable sized. It happens that
the existing calculation is correct for _most_ production binaries
produced by the Windows DDK, but if we get a binary with oddball
offsets, the PE loader could crash.
Changes from the supplied patch are:
- We don't really need to use the IMAGE_SIZEOF_NT_HEADER() macro when
computing how much of the header to return to callers of
pe_get_optional_header(). While it's important to take the variable
size of the header into account in other calculations, we never
actually look at anything outside the non-variable portion of the
header. This saves callers from having to allocate a variable sized
buffer off the heap (I purposely tried to avoid using malloc()
in subr_pe.c to make it easier to compile in both the -D_KERNEL and
!-D_KERNEL case), and since we're copying into a buffer on the
stack, we always have to copy the same amount of data or else
we'll trash the stack something fierce.
- We need <stddef.h> to get offsetof() in the !-D_KERNEL case.
- ndiscvt.c needs the IMAGE_FIRST_SECTION() macro too, since it does
a little bit of section pre-processing.
PR: kern/83477
and ndis_halt_nic(). It's been disabled for some time anyway, and
it turns out there's a possible deadlock in NdisMInitializeTimer() when
acquiring the miniport block lock to modify the timer list: it's
possible for a driver to call NdisMInitializeTimer() when the miniport
block lock has already been acquired by an earlier piece of code. You
can't acquire the same spinlock twice, so this can deadlock.
Also, implement MmMapIoSpace() and MmUnmapIoSpace(), and make
NdisMMapIoSpace() and NdisMUnmapIoSpace() use them. There are some
drivers that want MmMapIoSpace() and MmUnmapIoSpace() so that they can
map arbitrary register spaces not directly associated with their
device resources. For example, there's an Atheros driver for
a miniPci card (0x168C:0x1014) on the IBM Thinkpad x40 that wants
to map some I/O spaces at 0xF00000 and 0xE00000 which are held by
the acpi0 device. I don't know what it wants these ranges for,
but if it can't map and access them, the MiniportInitialize() method
fails.
This avoids the need for sched_bind() in the default case so that you
can start up the NDIS subsystem at boot time when only CPU 0 is running.
There are potentially ways to fix it so that the DPC threads aren't
started until after the other CPUs are launched, but doing it correctly
is tricky. You need to defer the startup of the ntoskrnl subsystem
(ntoskrnl_libinit()), not just defer ndis_attach().
For now, I don't think it will make much difference having just the
single DPC thread (I started out with just one anyway). Note that this
turns the KeSetTargetProcessorDpc() routine into a no-op, since the
CPU number in struct kdpc is now ignored.
is KeRaiseIrql(newirql, &oldirql), not oldirql = KeRaiseIrql(newirql).
(The macro ultimately translates to KfRaiseIrql() which does use
the latter API, so this has no effect on generated code.)
Also, wait for thread termination the right way: kthread_exit()
will ultimately do a wakeup(td->td_proc). This is the event we
should wait on. Eliminate the previous synchronization machinery
for this since it was never guaranteed to work correctly.
processor, to insure DPC thread 0 runs on CPU0, DPC thread 1 runs on
CPU1, and so on.
Elevate the priority of the workitem threads, though don't use as
high a priority as the DPC threads.
- Change ndis_return() from a DPC to a workitem so that it doesn't
run at DISPATCH_LEVEL (with the dispatcher lock held).
- In if_ndis.c, submit packets to the stack via (*ifp->if_input)() in
a workitem instead of doing it directly in ndis_rxeof(), because
ndis_rxeof() runs in a DPC, and hence at DISPATCH_LEVEL. This
implies that the 'dispatch level' mutex for the current CPU is
being held, and we don't want to call if_input while holding
any locks.
- Reimplement IoConnectInterrupt()/IoDisconnectInterrupt(). The original
approach I used to track down the interrupt resource (by scanning
the device tree starting at the nexus) is prone to problems when
two devices share an interrupt. (E.g removing ndis1 might disable
interrupts for ndis0.) The new approach is to multiplex all the
NDIS interrupts through a common internal dispatcher (ntoskrnl_intr())
and allow IoConnectInterrupt()/IoDisconnectInterrupt() to add or
remove interrupts from the dispatch list.
- Implement KeAcquireInterruptSpinLock() and KeReleaseInterruptSpinLock().
- Change the DPC and workitem threads to use the KeXXXSpinLock
API instead of mtx_lock_spin()/mtx_unlock_spin().
- Simplify the NdisXXXPacket routines by creating an actual
packet pool structure and using the InterlockedSList routines
to manage the packet queue.
- Only honor the value returned by OID_GEN_MAXIMUM_SEND_PACKETS
for serialized drivers. For deserialized drivers, we now create
a packet array of 64 entries. (The Microsoft DDK documentation
says that for deserialized miniports, OID_GEN_MAXIMUM_SEND_PACKETS
is ignored, and the driver for the Marvell 8335 chip, which is
a deserialized miniport, returns 1 when queried.)
- Clean up timer handling in subr_ntoskrnl.
- Add the following conditional debugging code:
NTOSKRNL_DEBUG_TIMERS - add debugging and stats for timers
NDIS_DEBUG_PACKETS - add extra sanity checking for NdisXXXPacket API
NTOSKRNL_DEBUG_SPINLOCKS - add test for spinning too long
- In kern_ndis.c, always start the HAL first and shut it down last,
since Windows spinlocks depend on it. Ntoskrnl should similarly be
started second and shut down next to last.
changes in MD code are trivial, before this change, trapsignal and
sendsig use discrete parameters, now they uses member fields of
ksiginfo_t structure. For sendsig, this change allows us to pass
POSIX realtime signal value to user code.
2. Remove cpu_thread_siginfo, it is no longer needed because we now always
generate ksiginfo_t data and feed it to libpthread.
3. Add p_sigqueue to proc structure to hold shared signals which were
blocked by all threads in the proc.
4. Add td_sigqueue to thread structure to hold all signals delivered to
thread.
5. i386 and amd64 now return POSIX standard si_code, other arches will
be fixed.
6. In this sigqueue implementation, pending signal set is kept as before,
an extra siginfo list holds additional siginfo_t data for signals.
kernel code uses psignal() still behavior as before, it won't be failed
even under memory pressure, only exception is when deleting a signal,
we should call sigqueue_delete to remove signal from sigqueue but
not SIGDELSET. Current there is no kernel code will deliver a signal
with additional data, so kernel should be as stable as before,
a ksiginfo can carry more information, for example, allow signal to
be delivered but throw away siginfo data if memory is not enough.
SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can
not be caught or masked.
The sigqueue() syscall allows user code to queue a signal to target
process, if resource is unavailable, EAGAIN will be returned as
specification said.
Just before thread exits, signal queue memory will be freed by
sigqueue_flush.
Current, all signals are allowed to be queued, not only realtime signals.
Earlier patch reviewed by: jhb, deischen
Tested on: i386, amd64
First and most importantly, I threw out the thread priority-twiddling
implementation of KeRaiseIrql()/KeLowerIrq()/KeGetCurrentIrql() in
favor of a new scheme that uses sleep mutexes. The old scheme was
really very naughty and sought to provide the same behavior as
Windows spinlocks (i.e. blocking pre-emption) but in a way that
wouldn't raise the ire of WITNESS. The new scheme represents
'DISPATCH_LEVEL' as the acquisition of a per-cpu sleep mutex. If
a thread on cpu0 acquires the 'dispatcher mutex,' it will block
any other thread on the same processor that tries to acquire it,
in effect only allowing one thread on the processor to be at
'DISPATCH_LEVEL' at any given time. It can then do the 'atomic sit
and spin' routine on the spinlock variable itself. If a thread on
cpu1 wants to acquire the same spinlock, it acquires the 'dispatcher
mutex' for cpu1 and then it too does an atomic sit and spin to try
acquiring the spinlock.
Unlike real spinlocks, this does not disable pre-emption of all
threads on the CPU, but it does put any threads involved with
the NDISulator to sleep, which is just as good for our purposes.
This means I can now play nice with WITNESS, and I can safely do
things like call malloc() when I'm at 'DISPATCH_LEVEL,' which
you're allowed to do in Windows.
Next, I completely re-wrote most of the event/timer/mutex handling
and wait code. KeWaitForSingleObject() and KeWaitForMultipleObjects()
have been re-written to use condition variables instead of msleep().
This allows us to use the Windows convention whereby thread A can
tell thread B "wake up with a boosted priority." (With msleep(), you
instead have thread B saying "when I get woken up, I'll use this
priority here," and thread A can't tell it to do otherwise.) The
new KeWaitForMultipleObjects() has been better tested and better
duplicates the semantics of its Windows counterpart.
I also overhauled the IoQueueWorkItem() API and underlying code.
Like KeInsertQueueDpc(), IoQueueWorkItem() must insure that the
same work item isn't put on the queue twice. ExQueueWorkItem(),
which in my implementation is built on top of IoQueueWorkItem(),
was also modified to perform a similar test.
I renamed the doubly-linked list macros to give them the same names
as their Windows counterparts and fixed RemoveListTail() and
RemoveListHead() so they properly return the removed item.
I also corrected the list handling code in ntoskrnl_dpc_thread()
and ntoskrnl_workitem_thread(). I realized that the original logic
did not correctly handle the case where a DPC callout tries to
queue up another DPC. It works correctly now.
I implemented IoConnectInterrupt() and IoDisconnectInterrupt() and
modified NdisMRegisterInterrupt() and NdisMDisconnectInterrupt() to
use them. I also tried to duplicate the interrupt handling scheme
used in Windows. The interrupt handling is now internal to ndis.ko,
and the ndis_intr() function has been removed from if_ndis.c. (In
the USB case, interrupt handling isn't needed in if_ndis.c anyway.)
NdisMSleep() has been rewritten to use a KeWaitForSingleObject()
and a KeTimer, which is how it works in Windows. (This is mainly
to insure that the NDISulator uses the KeTimer API so I can spot
any problems with it that may arise.)
KeCancelTimer() has been changed so that it only cancels timers, and
does not attempt to cancel a DPC if the timer managed to fire and
queue one up before KeCancelTimer() was called. The Windows DDK
documentation seems to imply that KeCantelTimer() will also call
KeRemoveQueueDpc() if necessary, but it really doesn't.
The KeTimer implementation has been rewritten to use the callout API
directly instead of timeout()/untimeout(). I still cheat a little in
that I have to manage my own small callout timer wheel, but the timer
code works more smoothly now. I discovered a race condition using
timeout()/untimeout() with periodic timers where untimeout() fails
to actually cancel a timer. I don't quite understand where the race
is, using callout_init()/callout_reset()/callout_stop() directly
seems to fix it.
I also discovered and fixed a bug in winx32_wrap.S related to
translating _stdcall calls. There are a couple of routines
(i.e. the 64-bit arithmetic intrinsics in subr_ntoskrnl) that
return 64-bit quantities. On the x86 arch, 64-bit values are
returned in the %eax and %edx registers. However, it happens
that the ctxsw_utow() routine uses %edx as a scratch register,
and x86_stdcall_wrap() and x86_stdcall_call() were only preserving
%eax before branching to ctxsw_utow(). This means %edx was getting
clobbered in some cases. Curiously, the most noticeable effect of this
bug is that the driver for the TI AXC110 chipset would constantly drop
and reacquire its link for no apparent reason. Both %eax and %edx
are preserved on the stack now. The _fastcall and _regparm
wrappers already handled everything correctly.
I changed if_ndis to use IoAllocateWorkItem() and IoQueueWorkItem()
instead of the NdisScheduleWorkItem() API. This is to avoid possible
deadlocks with any drivers that use NdisScheduleWorkItem() themselves.
The unicode/ansi conversion handling code has been cleaned up. The
internal routines have been moved to subr_ntoskrnl and the
RtlXXX routines have been exported so that subr_ndis can call them.
This removes the incestuous relationship between the two modules
regarding this code and fixes the implementation so that it honors
the 'maxlen' fields correctly. (Previously it was possible for
NdisUnicodeStringToAnsiString() to possibly clobber memory it didn't
own, which was causing many mysterious crashes in the Marvell 8335
driver.)
The registry handling code (NdisOpen/Close/ReadConfiguration()) has
been fixed to allocate memory for all the parameters it hands out to
callers and delete whem when NdisCloseConfiguration() is called.
(Previously, it would secretly use a single static buffer.)
I also substantially updated if_ndis so that the source can now be
built on FreeBSD 7, 6 and 5 without any changes. On FreeBSD 5, only
WEP support is enabled. On FreeBSD 6 and 7, WPA-PSK support is enabled.
The original WPA code has been updated to fit in more cleanly with
the net80211 API, and to eleminate the use of magic numbers. The
ndis_80211_setstate() routine now sets a default authmode of OPEN
and initializes the RTS threshold and fragmentation threshold.
The WPA routines were changed so that the authentication mode is
always set first, followed by the cipher. Some drivers depend on
the operations being performed in this order.
I also added passthrough ioctls that allow application code to
directly call the MiniportSetInformation()/MiniportQueryInformation()
methods via ndis_set_info() and ndis_get_info(). The ndis_linksts()
routine also caches the last 4 events signalled by the driver via
NdisMIndicateStatus(), and they can be queried by an application via
a separate ioctl. This is done to allow wpa_supplicant to directly
program the various crypto and key management options in the driver,
allowing things like WPA2 support to work.
Whew.
osf1_signal.c:1.41, amd64/amd64/trap.c:1.291, linux_socket.c:1.60,
svr4_fcntl.c:1.36, svr4_ioctl.c:1.23, svr4_ipc.c:1.18, svr4_misc.c:1.81,
svr4_signal.c:1.34, svr4_stat.c:1.21, svr4_stream.c:1.55,
svr4_termios.c:1.13, svr4_ttold.c:1.15, svr4_util.h:1.10,
ext2_alloc.c:1.43, i386/i386/trap.c:1.279, vm86.c:1.58,
unaligned.c:1.12, imgact_elf.c:1.164, ffs_alloc.c:1.133:
Now that Giant is acquired in uprintf() and tprintf(), the caller no
longer leads to acquire Giant unless it also holds another mutex that
would generate a lock order reversal when calling into these functions.
Specifically not backed out is the acquisition of Giant in nfs_socket.c
and rpcclnt.c, where local mutexes are held and would otherwise violate
the lock order with Giant.
This aligns this code more with the eventual locking of ttys.
Suggested by: bde
