parameter).
Keep using it only in the i386 NOTES for now. It is fairly MI, but it
doesn't use bus-space and has a couple of i386 i/o instructions in pci
intitialization.
intent was to make sure that message structs allocated off of the stack were
4-byte aligned. However, the macros as defined did absolutely nothing.
And since I2O forces you to manually copy messages down to the hardware, there
really is no point of enforced alignment anyways.
rename the control device from rasr%d to asr%d. This starts us down the
path of divorcing ourselves from a very bogus design in the management
apps. Since the apps are open source now, they will likely be updated
and fixed before 5.3.
Adjust staticness and a variable name for the split of cy.c into cy.c and
cy_isa.c. Use the new header required for the split to avoid repeating
declarations in cy_pci.c.
Put @includes in a better spot. Fix many cases of 2 space indents and spaces
between a function name and the parens. Use KASSERT instead of a home-rolled
ASSERT. Remove some undeeded caddr casts.
- Define option FORCECONSPEED to force the serial console to
be CONSPEED. I've run into a lot of boards in which
the detect for prior speed doesn't work and ends up with
broken console since it is at the wrong speed.
- If a serial port is marked as a console, but console=vidconsole
and if the serial ports doesn't exist it will be probed and
attached at a 8250 chip. Then writes to that will freeze the
system.
- Add an option flags 0x400000 to mark this as a potential
comconsole in-case the one flaged with 0x10 does not exist
in the system.
This makes it easier to deploy on systems with one or two serial ports.
Obtained from: IronPort
- Use the dh_inserted member of the dispatch header in the Windows
timer structure to indicate that the timer has been "inserted into
the timer queue" (i.e. armed via timeout()). Use this as the value
to return to the caller in KeCancelTimer(). Previously, I was using
callout_pending(), but you can't use that with timeout()/untimeout()
without creating a potential race condition.
- Make ntoskrnl_init_timer() just a wrapper around ntoskrnl_init_timer_ex()
(reduces some code duplication).
- Drop Giant when entering if_ndis.c:ndis_tick() and
subr_ntorkrnl.c:ntoskrnl_timercall(). At the moment, I'm forced to
use system callwheel via timeout()/untimeout() to handle timers rather
than the callout API (struct callout is too big to fit inside the
Windows struct KTIMER, so I'm kind of hosed). Unfortunately, all
the callouts in the callwhere are not marked as MPSAFE, so when
one of them fires, it implicitly acquires Giant before invoking the
callback routine (and releases it when it returns). I don't need to
hold Giant, but there's no way to stop the callout code from acquiring
it as long as I'm using timeout()/untimeout(), so for now we cheat
by just dropping Giant right away (and re-acquiring it right before
the routine returns so keep the callout code happy). At some point,
I will need to solve this better, but for now this should be a suitable
workaround.
- Remove second license, the first was not that different and should be
fine.
- Add nexus_attach(), and do not perform its task in nexus_probe() any
more.
- Remove nexus_write_ivar(), since it was quite pointless.
- Remove superfluous devinfo members.
- Clean up some comments, minor style issues and prototypes.
as dependent on binutils features/quirks as the current one. This one
loads plain .o files without having to mess with shared object mode.
This happens to be essential on amd64, because binutils hasn't implemented
all the quirks/features that we need for producing the hack non-PIC shared
objects. As it turned out, .o format isn't all that inconvenient after
all. It looks like the ability to use the same .o files for linking
directly into a static kernel or loading as a module might be worth it.
It is still very much a work-in-progress, but it is almost usable. Other
changes are still needed in order to use it though, these have not been
committed yet. There is still a memory corruption/overrun bug somewhere.
For example, test modules load and work, but the machine explodes a few
minutes later in vm_forkproc() or the like. Notable missing things
include kldxref support, and loader(8) support. I wanted to figure out
a working baseline set of code first.
things which compare /etc/fstab entries to results from
getfsstat(). The real way to fix this is to make 'ufs2'
a recognized filesystem (for real, no beating around the
bush).
This should fix things like 'umount -a -t ufs' now.
Appologies for the previous breakage.
boot0sio.s was repo-copied to boot0.S.
- Rename boot0ext.s to boot0ext.S, to stay consistent
with other preprocessed asm files around here, and
for better portability.
Repocopied by: joe
condition where kse_wakeup() doesn't yet see them in (interruptible)
sleep queues. Also add an upcall check to sleepqueue_catch_signals()
suggested by jhb.
This commit should fix recent mysql hangs.
Reviewed by: jhb, davidxu
Mysql'd by: Robin P. Blanchard <robin.blanchard at gactr uga edu>
switch to using C99-style comments everywhere in preprocessed
assembler. The reason is that lines starting with the regexp
'^[[:space:]]#' are treated as preprocessing directives, and
while it seems to work now with GCC, it's not necessarily has
to work. Use C99 comments `//' for the trailing comments to
save whitespace.
bridges, the EBus bridge has resource ranges it claims exclusively to
map its children into in its BARs. Hence, we need to allocate these
completely and manage them for the children, instead of just passing
allocations through to the PCI layer as we did before.
While being there, split ebus_probe(), which did also contain code
normally belonging into the attach method, into ebus_probe() and
ebus_attach(), and perform some minor cleanups.
correct interrupt source.
- Cache a pointer to the i8254_intsrc's pending method to avoid several
pointer indirections in i8254_get_timecount().
Reported by: bde
Merge boot0.s and boot0sio.s into boot0_512.s controlled by "#ifdef SIO".
Add Makefile magic to generate boot0.s and boot0sio.s from boot0_512.s.
The compile boot0 and boot0sio have unchanged MD5 checksums.
channels. This also work when PCI native mode has been selected
(patch for /sys/dev/pci/pci.c needed for that) since pci_get_progif
uses the saved value for progif, not the one stored after we may have
changed from legacy mode to native PCI mode.
jail, which is less restrictive but allows for more flexible
jail usage (for those who are willing to make the sacrifice).
The default is off, but allowing raw sockets within jails can
now be accomplished by tuning security.jail.allow_raw_sockets
to 1.
Turning this on will allow you to use things like ping(8)
or traceroute(8) from within a jail.
The patch being committed is not identical to the patch
in the PR. The committed version is more friendly to
APIs which pjd is working on, so it should integrate
into his work quite nicely. This change has also been
presented and addressed on the freebsd-hackers mailing
list.
Submitted by: Christian S.J. Peron <maneo@bsdpro.com>
PR: kern/65800
libufs, which only works for Charlie root.
This change reverts the introduction of libufs and moves the
check into the kernel. Since the f_fstypename is the same
for both ufs and ufs2, we check fs_magic for presence of
ufs2 and copy "ufs2" explicitly instead.
Submitted by: Christian S.J. Peron <maneo@bsdpro.com>
possible while maintaining compatibility with the widest range of TCP stacks.
The algorithm is as follows:
---
For connections in the ESTABLISHED state, only resets with
sequence numbers exactly matching last_ack_sent will cause a reset,
all other segments will be silently dropped.
For connections in all other states, a reset anywhere in the window
will cause the connection to be reset. All other segments will be
silently dropped.
---
The necessity of accepting all in-window resets was discovered
by jayanth and jlemon, both of whom have seen TCP stacks that
will respond to FIN-ACK packets with resets not meeting the
strict last_ack_sent check.
Idea by: Darren Reed
Reviewed by: truckman, jlemon, others(?)
1) In pci.c, we need to check the child device's state, not the parent
device's state.
2) In acpi_pci.c, we have to run the power state change after the acpi
method when the old_state is > new state, not the other way around.
Submitted by: Dmitry Remesov
PR: 65694
1. rt_check() cleanup:
rt_check() is only necessary for some address families to gain access
to the corresponding arp entry, so call it only in/near the *resolve()
routines where it is actually used -- at the moment this is
arpresolve(), nd6_storelladdr() (the call is embedded here),
and atmresolve() (the call is just before atmresolve to reduce
the number of changes).
This change will make it a lot easier to decouple the arp table
from the routing table.
There is an extra call to rt_check() in if_iso88025subr.c to
determine the routing info length. I have left it alone for
the time being.
The interface of arpresolve() and nd6_storelladdr() now changes slightly:
+ the 'rtentry' parameter (really a hint from the upper level layer)
is now passed unchanged from *_output(), so it becomes the route
to the final destination and not to the gateway.
+ the routines will return 0 if resolution is possible, non-zero
otherwise.
+ arpresolve() returns EWOULDBLOCK in case the mbuf is being held
waiting for an arp reply -- in this case the error code is masked
in the caller so the upper layer protocol will not see a failure.
2. arpcom untangling
Where possible, use 'struct ifnet' instead of 'struct arpcom' variables,
and use the IFP2AC macro to access arpcom fields.
This mostly affects the netatalk code.
=== Detailed changes: ===
net/if_arcsubr.c
rt_check() cleanup, remove a useless variable
net/if_atmsubr.c
rt_check() cleanup
net/if_ethersubr.c
rt_check() cleanup, arpcom untangling
net/if_fddisubr.c
rt_check() cleanup, arpcom untangling
net/if_iso88025subr.c
rt_check() cleanup
netatalk/aarp.c
arpcom untangling, remove a block of duplicated code
netatalk/at_extern.h
arpcom untangling
netinet/if_ether.c
rt_check() cleanup (change arpresolve)
netinet6/nd6.c
rt_check() cleanup (change nd6_storelladdr)
- Fix some comments; remove numerous superfluous or outdated ones.
- Correctly pass on the requesting device when handing requests up
to the parent bus.
- Use the complete device name, including unit number, to build the
IOMMU instance name.
- Inline a function that was only used once, and was trivial.
consistently with the rest of the code, use IFP2AC(ifp) to access
the arpcom structure given the ifp.
In this case also fix a difference in assumptions WRT the rest of
the net/ sources: it is not the 'struct *softc' that starts with a
'struct arpcom', but a 'struct arpcom' that starts with a
'struct ifnet'
- use ifp instead if &ac->ac_if in a couple of nd6* calls;
this removes a useless dependency.
- use IFP2AC(ifp) instead of an extra variable to point to the struct arpcom;
this does not remove the nesting dependency between arpcom and ifnet but
makes it more evident.
caller to vm_page_grab(). Although this gives VM_ALLOC_ZERO a
different meaning for vm_page_grab() than for vm_page_alloc(), I feel
such change is necessary to accomplish other goals. Specifically, I
want to make the PG_ZERO flag immutable between the time it is
allocated by vm_page_alloc() and freed by vm_page_free() or
vm_page_free_zero() to avoid locking overheads. Once we gave up on
the ability to automatically recognize a zeroed page upon entry to
vm_page_free(), the ability to mutate the PG_ZERO flag became useless.
Instead, I would like to say that "Once a page becomes valid, its
PG_ZERO flag must be ignored."
added an arbitrary delay to our readings, causing us to use the ACPI-safe
read method when not necessary. Submitted by: bde
Old:
ACPI timer looks GOOD min = 3, max = 5, width = 2
ACPI timer looks BAD min = 3, max = 19, width = 16
ACPI timer looks GOOD min = 3, max = 5, width = 2
ACPI timer looks GOOD min = 3, max = 5, width = 2
ACPI timer looks GOOD min = 3, max = 5, width = 2
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 5, width = 2
ACPI timer looks BAD min = 3, max = 19, width = 16
ACPI timer looks GOOD min = 3, max = 5, width = 2
ACPI timer looks GOOD min = 3, max = 4, width = 1
Timecounter "ACPI-safe" frequency 3579545 Hz quality 1000
New:
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 4, width = 1
ACPI timer looks GOOD min = 3, max = 4, width = 1
Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000
Also, reduce unnecesary overhead in ACPI-fast by remove the barrier for
reads. The timer in the ACPI-fast case is known to increase monotonically
so there is no need to serialize access to it.
misplaced forward declarations of structs). This also reduces namespace
pollution (the misplaced declarations were declared in the !_KERNEL case
when they are not used).
would actually map the file with read access enabled. According to
http://www.opengroup.org/onlinepubs/007904975/functions/mmap.html this is
an error. Similarly, an madvise(..., MADV_WILLNEED) would enable read
access on a virtual address range that was PROT_NONE.
The solution implemented herein is (1) to pass a vm_prot_t to
vm_map_pmap_enter() describing the allowed access and (2) to make
vm_map_pmap_enter() responsible for understanding the limitations of
pmap_enter_quick().
Submitted by: "Mark W. Krentel" <krentel@dreamscape.com>
PR: kern/64573
from tcp_hostcache would have overridden a (now) lower MTU of
an interface or route that changed since first PMTU discovery.
The bug would have caused TCP to redo the PMTU discovery when
not strictly necessary.
Make a comment about already pre-initialized default values
more clear.
Reviewed by: sam
state. Apparently it happens when both devices try to disconnect RFCOMM
multiplexor channel at the same time.
The scenario is as follows:
- local device initiates RFCOMM connection to the remote device. This
creates both RFCOMM multiplexor channel and data channel;
- remote device terminates RFCOMM data channel (inactivity timeout);
- local device acknowledges RFCOMM data channel termination. Because
there is no more active data channels and local device has initiated
connection it terminates RFCOMM multiplexor channel;
- remote device does not acknowledges RFCOMM multiplexor channel
termination. Instead it sends its own request to terminate RFCOMM
multiplexor channel. Even though local device acknowledges RFCOMM
multiplexor channel termination the remote device still keeps
L2CAP connection open.
Because of hanging RFCOMM multiplexor channel subsequent RFCOMM
connections between local and remote devices will fail.
Reported by: Johann Hugo <jhugo@icomtek.csir.co.za>
modules is a very nice way to produce hard-to-find panics. Who would look for
a bug in a Makefile anyway?
Has anyone seen the pointy hat? :-o
Approved by: njl (mentor)
ip_id again. ip_id is already set to the ip_id of the encapsulated packet.
Make a comment about mbuf allocation failures more realistic.
Reviewed by: sobomax
resource pre-allocation. The problem is that the BARs of the EBus bridges
contain the ranges for the resources for the EBus devices beyond the bridge.
So when the EBus code tries to allocate the resource for an EBus device
it's already allocated by the PCI code.
To be removed again as soon as we have a proper solution in the EBus Code.
Reviewed by: tmm
Approved by: marcel (mentor)
source address of a packet exists in the routing table. The
default route is ignored because it would match everything and
render the check pointless.
This option is very useful for routers with a complete view of
the Internet (BGP) in the routing table to reject packets with
spoofed or unrouteable source addresses.
Example:
ipfw add 1000 deny ip from any to any not versrcreach
also known in Cisco-speak as:
ip verify unicast source reachable-via any
Reviewed by: luigi
secondary bus is 0, we program the primary bus, the secondary bus and
the suborindate bus. This isn't ideal, since we start at parent_bus +
1 and store this in a static.
Ideally, we'd walk the tree and assign bus numbers. However, that's
harder to accomplish without some help from the bus layer which we're
not planning on doing that until 6.
This fixes my CardBus problems on my Sony PCG-Z1WA, and might fix the
Dells that have had problems.
sched_ule, in January 2004. Looking at this, "pagezero" is (one of) the
culprit(s). We had no provision for processes with P_NOLOAD set. With
pagezero not running at PRI_ITHD, kseq_load_{add,rem} count pagezero as
another-normal-process, thus the "expected-plus-one" load reported in
the above thread.
Submitted by: Nikos Ntarmos <ntarmos@ceid.upatras.gr>
gadgets (hotkeys, lcd, ...) on Asus laptops. I aim to closely track the
acpi4asus project which implements these features in the Linux kernel.
If this breaks your laptop, please let me know how it does it :-)
Approved by: njl (mentor)
there are a lot of other dependencies that preclude the kernel from
working). Instead, have a more generic note that isa should not be
removed. This should be less confusing for users.
(I hope.)
My original instinct to make ndis_return_packet() asynchronous was correct.
Making ndis_rxeof() submit packets to the stack asynchronously fixes
one recursive spinlock acquisition, but it's also possible for it to
happen via the ndis_txeof() path too. So:
- In if_ndis.c, revert ndis_rxeof() to its old behavior (and don't bother
putting ndis_rxeof_serial() back since we don't need it anymore).
- In kern_ndis.c, make ndis_return_packet() submit the call to the
MiniportReturnPacket() function to the "ndis swi" thread so that
it always happens in another context no matter who calls it.
workaround was for hardware where the clock was not latched, not for
hardware that was too slow. Also, make variable names more specific for ddb
printing.
While I would have prefered to have a solution that didn't move
knowledge of this into the pci layer. However, this is literally the
only exception that's listed in the PCI standard to the usual way of
decoding BARs. atapci devices in legacy mode now ignore the first 4
bars and hard code the values to the legacy ide values (well, for each
of the controllers that are in legacy mode). The 5th bar is handled
normally.
Remove the zero bar handling. zero bars should be ignored at all
other times, and since we handle that specially, we don't need the
older workaround.
what the ACPI-safe workaround is intended to fix. Requested by phk.
Set the bushandle and tag when attaching the timer, don't do it each time
in read_counter(). Pointed out by bde.
Move test_counter() to the end. Staticize acpi_timer_reg.
Clearly comment the assumptions on the structure of keys (addresses)
and masks, and introduce a macro, LEN(p), to extract the size of these
objects instead of using *(u_char *)p which might be confusing.
Comment the confusion in the types used to pass around pointers
to keys and masks, as a reminder to fix that at some point.
Add a few comments on what some functions do.
Comment a probably inefficient (but still correct) section of code
in rn_walktree_from()
The object code generated after this commit is the same as before.
At some point we should also change same variable identifiers such
as "t, tt, ttt" to fancier names such as "root, left, right" (just
in case someone wants to understand the code!), replace misspelling
of NULL as 0, remove 'register' declarations that make little sense
these days.
like "the foo(4) manual page" to "foo(4)". Uniformized the remaining
instances of "manual page" and "manpage" to "man page". Uniformized
some nearby sentence breaks. Reformatted the whole paragraph containing
these changes only for DUMMYNET.
of you with other cards, please do review and test the drivers for
MP-safety and disable Giant in the interrupt routines when you are
sure of proper functionality.
wireless ever since I added the new spinlock code. Previously, I added
a special ndis_rxeof_serial() function to insure that when we receive
a packet, we never end up calling the MiniportReturnPacket() routine
until after the receive handler has finished. I set things up so that
ndis_rxeof_serial() would only be used for serialized miniports since
they depend on this property. Well, it turns out deserialized miniports
depend on a similar property: you can't let MiniportReturnPacket() be
called from the same context as the receive handler at all. The 2100B
driver happens to use a single spinlock for all of its synchronization,
and it tries to acquire it both while in MiniportHandleInterrupt() and
in MiniportReturnPacket(), so if we call MiniportReturnPacket() from
the MiniportHandleInterrupt() context, we will end up trying to acquire
the spinlock recursively, which you can't do.
To fix this, I made the ndis_rxeof_serial() handler the default. An
alternate solution would be to make ndis_return_packet() submit
the call to MiniportReturnPacket() to the NDIS task queue thread.
I may do that in the future, after I've tested things a bit more.
supported. Symptoms of this bug included unnecessary use of ACPI-safe
and a dmesg that has deltas of about 2^24:
ACPI timer looks BAD min = 2, max = 16777206, width = 16777204
ACPI timer looks BAD min = 2, max = 7, width = 5
ACPI timer looks GOOD min = 4, max = 5, width = 1
ACPI timer looks BAD min = 2, max = 16777206, width = 16777204
ACPI timer looks BAD min = 2, max = 7, width = 5
ACPI timer looks BAD min = 2, max = 16777210, width = 16777208
ACPI timer looks BAD min = 4, max = 16777189, width = 16777185
ACPI timer looks GOOD min = 4, max = 5, width = 1
ACPI timer looks BAD min = 2, max = 7, width = 5
ACPI timer looks BAD min = 4, max = 16777189, width = 16777185
To fix this:
* Use a 32 bit timecounter mask when the timer is 32 bits.
* In test_counter(), use the acpi_TimerDelta function which handles 24/32
bit timers and wraparound.
Miscellaneous fixes:
* Use C99 initializers for timecounter struct.
* Use u_int and uint32_t where appropriate instead of unsigned.
* Remove whitespace-only lines
* Remove the old PIIX4 PCI workaround. The timecounter testing code has
been in use for long enough to prove it's functional.
globally available. acpi_TimerDelta() subtracts two readings from the
ACPI PM timer and returns the difference. It properly distinguishes between
24-bit and 32-bit timers and handles wraparound.
2. Document that this means that kernel modules must be rebuilt.
3. While I'm here, fix my sorting error in callout.h
Requested by: many [1], scottl [2], bde [3]
it checked for rt == NULL after dereferencing the pointer).
We never check for those events elsewhere, so probably these checks
might go away here as well.
Slightly simplify (and document) the logic for memory allocation
in rt_setgate().
The rest is mostly style changes -- replace 0 with NULL where appropriate,
remove the macro SA() that was only used once, remove some useless
debugging code in rt_fixchange, explain some odd-looking casts.
implementation taken directly from OpenBSD.
I've resisted committing this for quite some time because of concern over
TIME_WAIT recycling breakage (sequential allocation ensures that there is a
long time before ports are recycled), but recent testing has shown me that
my fears were unwarranted.
TIME_WAIT recycling cases I was able to generate with http testing tools.
In short, as the old algorithm relied on ticks to create the time offset
component of an ISN, two connections with the exact same host, port pair
that were generated between timer ticks would have the exact same sequence
number. As a result, the second connection would fail to pass the TIME_WAIT
check on the server side, and the SYN would never be acknowledged.
I've "fixed" this by adding random positive increments to the time component
between clock ticks so that ISNs will *always* be increasing, no matter how
quickly the port is recycled.
Except in such contrived benchmarking situations, this problem should never
come up in normal usage... until networks get faster.
No MFC planned, 4.x is missing other optimizations that are needed to even
create the situation in which such quick port recycling will occur.
a NULL crsbuf pointer. This shouldn't happen if it returns AE_OK. We'll
figure out why this is happening later.
Submitted by: Bruno Ducrot <ducrot@poupinou.org>
routine since the error will be reported back to the user buffer.
This will quiet down the bootverbose case when using an ACU which
does brute force discovery of the physical and logical devices.
the same process as the current thread it makes absolutely
no sense to lock the parent process through the pointer in
said thread.
Submitted by: pho (with minor correction)
Pointy Hat To: mtm
this patch were submitted by Maurycy Pawlowski-Wieronski. In addition
to Maurycy's change, break out softc tear down from ppp_clone_destroy()
into ppp_destroy() rather than performing a convoluted series of
extraction casts and indirections during tear down at mod unload.
Submitted by: Maurycy Pawlowski-Wieronski <maurycy@fouk.org>
of the struct, so that a placeholder for it (or unportable C99
initializers) are not needed for entries that don't use it. Use a C99
initializer for the 1 entry that uses it. Removed 91 placeholders.
This also restores API compatibility with NetBSD and RELENG_4 for most
entries.
+ remove useless wrappers around bcmp(), bcopy(), bzero().
The code assumes that bcmp() returns 0 if the size is 0, but
this is true for both the libc and the libkern versions.
+ nuke Bcmp, Bzero, Bcopy from radix.h now that nobody uses them anymore.
Removed the requirement for a particular subvendor/subproduct in
rev.1.26 (VScom PCI-800L card). While the BARs, etc., may depend on
the sub-ids, this is not known to be so, and I think it is better to
guess that they don't. The decision to check sub-id checks in this
file is apparently random; for VScom cards they were checked in 3 of
8 cases.
Reviewed by: timeout by committer (joerg) after 6 months
there so there are no ABI changes);
+ replace 5 redefinitions of the IPF2AC macro with one in if_arp.h
Eventually (but before freezing the ABI) we need to get rid of
struct arpcom (initially with the help of some smart #defines
to avoid having to touch each and every driver, see below).
Apart from the struct ifnet, struct arpcom now only stores a copy
of the MAC address (ac_enaddr, but we already have another copy in
the struct ifnet -- if_addrhead), and a netgraph-specific field
which is _always_ accessed through the ifp, so it might well go
into the struct ifnet too (where, besides, there is already an entry
for AF_NETGRAPH data...)
Too bad ac_enaddr is widely referenced by all drivers. But
this can be fixed as follows:
#define ac_enaddr ac_if.the_original_ac_enaddr_in_struct_ifnet
(note that the right hand side would likely be a pointer rather than
the base address of an array.)
+ replace 0 with NULL where appropriate (not complete)
+ remove register declaration while there
+ add argument names to function prototypes to have a better idea of
what they are used for
+ add 'const' qualifiers in 3 places
