that should be better.
The old code counted references to mbuf clusters by using the offset
of the cluster from the start of memory allocated for mbufs and
clusters as an index into an array of chars, which did the reference
counting. If the external storage was not a cluster then reference
counting had to be done by the code using that external storage.
NetBSD's system of linked lists of mbufs was cosidered, but Alfred
felt it would have locking issues when the kernel was made more
SMP friendly.
The system implimented uses a pool of unions to track external
storage. The union contains an int for counting the references and
a pointer for forming a free list. The reference counts are
incremented and decremented atomically and so should be SMP friendly.
This system can track reference counts for any sort of external
storage.
Access to the reference counting stuff is now through macros defined
in mbuf.h, so it should be easier to make changes to the system in
the future.
The possibility of storing the reference count in one of the
referencing mbufs was considered, but was rejected 'cos it would
often leave extra mbufs allocated. Storing the reference count in
the cluster was also considered, but because the external storage
may not be a cluster this isn't an option.
The size of the pool of reference counters is available in the
stats provided by "netstat -m".
PR: 19866
Submitted by: Bosko Milekic <bmilekic@dsuper.net>
Reviewed by: alfred (glanced at by others on -net)
if you kldload this driver, all the subordinate devices are probed/attached
as expected. But this is not the case when the driver is statically compiled
into the kernel. Since I do most of my testing with modules, I failed to
notice this. I'm not sure if it's intended behavior or not. I think it may
be, but it seems a little counter-intuitive.
ether_ifdetach().
The former consolidates the operations of if_attach(), ng_ether_attach(),
and bpfattach(). The latter consolidates the corresponding detach operations.
Reviewed by: julian, freebsd-net
after autoneg so we make sure to set the link state and duplex mode
correctly.
- Make sure to set the 'ignore pause frames' bit on the XMAC.
- Small linewrap fix.
of the individual drivers and into the common routine ether_input().
Also, remove the (incomplete) hack for matching ethernet headers
in the ip_fw code.
The good news: net result of 1016 lines removed, and this should make
bridging now work with *all* Ethernet drivers.
The bad news: it's nearly impossible to test every driver, especially
for bridging, and I was unable to get much testing help on the mailing
lists.
Reviewed by: freebsd-net
- Break out the support for the XMAC II's PHY into an miibus driver.
- Reorganize the probe/attach stuff using newbus. Each XMAC is now
attached to the parent GEnesis controller using newbus. This is
necessary since each XMAC must also have an attached miibus, and
the miibus read/write register routines need to be able to get
at the softc struct for each XMAC, not the one for the parent
controller. This allows me to get rid of the grotty code I added
for selecting the unit numbers for the ifnet interfaces: the unit
numbers are now derived from the newbus-assigned unit numbers,
which should track with the ifnet interface numbers. I think.
At the very least, there should never be any collisions.
- Add support for the SK-9821 and SK-9822 1000baseTX adapters. Special
thanks to SysKonnect for loaning me two adapters for testing.
there are stubs compiled into the kernel if BPF support is not enabled,
there aren't any problems with unresolved symbols. The modules in /modules
are compiled with BPF support enabled anyway, so the most this will do is
bloat GENERIC a little.
declaration for the interface driver from "foo" to "if_foo" but leave the
declaration for the miibus attached to the interface driver alone. This
lets the internal module name be "if_foo" while still allowing the miibus
instances to attach to "foo."
This should allow ifconfig to autoload driver modules again without
breaking the miibus attach.
This whole idea isn't going to work until somebody makes the bus/kld
code smarter. The idea here is to change the module's internal name
from "foo" to "if_foo" so that ifconfig can tell a network driver from
a non-network one. However doing this doesn't work correctly no matter
how you slice it. For everything to work, you have to change the name
in both the driver_t struct and the DRIVER_MODULE() declaration. The
problems are:
- If you change the name in both places, then the kernel thinks that
the device's name is now "if_foo", so you get things like:
if_foo0: <FOO ethernet> irq foo at device foo on pcifoo
if_foo0: Ethernet address: foo:foo:foo:foo:foo:foo
This is bogus. Now the device name doesn't agree with the logical
interface name. There's no reason for this, and it violates the
principle of least astonishment.
- If you leave the name in the driver_t struct as "foo" and only
change the names in the DRIVER_MODULE() declaration to "if_foo" then
attaching drivers to child devices doesn't work because the names don't
agree. This breaks miibus: drivers that need to have miibuses and PHY
drivers attached never get them.
In other words: damned if you do, damned if you don't.
This needs to be thought through some more. Since the drivers that
use miibus are broken, I have to change these all back in order to
make them work again. Yes this will stop ifconfig from being able
to demand load driver modules. On the whole, I'd rather have that
than having the drivers not work at all.
This fixes, at least, panics in ncr_attach() on i386's with about 5MB
of memory. The restriction was a hack to leave some low memory for ISA
DMA, but on i386's we now allocate pages from the top down, so all the
restriction did was cause our allocations to fail when there is no free
memory above 1MB.
the driver_t declaration should be "skc" not "sk". Technically, "skc"
is the parent PCI device (the SysKonnect GEnesis controller) and "sk0"
and "sk1" are the network interfaces that get attached to it.
interrupts that were scheduled. Testing shows it didn't really do very much
and it makes the code a little more complicated (which is never a good thing).
Also fix the rambuffer offset initialization for the 512K/64K SRAM case
(512K total using 64K chips). It should be 0. The only case with a
non-standard rambuffer offset address is 1024K/64K according to the
SysKonnect manual. (My card has the 1024/64 configuration and I don't know
which card uses the 512/64 configuration, if any, so I'm not sure that
this was really a problem for anyone.)
gigabit ethernet adapters. This includes two single port cards
(single mode and multimode fiber) and two dual port cards (also single
mode and multimode fiber). SysKonnect is currently the only
vendor with a dual port gigabit ethernet NIC.
The ports on dual port adapters are treated as separate network
interfaces. Thus, if you have an SK-9844 dual port SX card, you
should have both sk0 and sk1 interfaces attached. Dual port cards
are implemented using two XMAC II chips connected to a single
SysKonnect GEnesis controller. Hence, dual port cards are really
one PCI device, as opposed to two separate PCI devices connected
through a PCI to PCI bridge. Note that SysKonnect's drivers use
the two ports for failover purposes rather that as two separate
interfaces, plus they don't support jumbo frames. This applies to
their Linux driver too. :)
Support is provided for hardware multicast filtering, BPF and
jumbo frames. The SysKonnect cards support TCP checksum offload
however this feature is not currently enabled (hopefully it will
be once we get checksum offload support).
There are still a few things that need to be implemeted, like
the ability to communicate with the on-board LM80 voltage/temperature
monitor, but I wanted to get the driver under CVS control and into
-current so people could bang on it.
A big thanks for SysKonnect for making all their programming info
for these cards (and for their FDDI and token ring cards) available
without NDA (see www.syskonnect.com).
