It seems the D_PSEUDO flag was meant to allow make_dev() to return NULL.
Nowadays we have a different interface for that; make_dev_p(). There's
no need to keep it there.
While there, remove an unneeded D_NEEDMINOR from the gpio driver.
Discussed with: gonzo@ (gpio)
If a selinfo object is recorded (via selrecord()) and then it is
quickly destroyed, with the waiters missing the opportunity to awake,
at the next iteration they will find the selinfo object destroyed,
causing a PF#.
That happens because the selinfo interface has no way to drain the
waiters before to destroy the registered selinfo object. Also this
race is quite rare to get in practice, because it would require a
selrecord(), a poll request by another thread and a quick destruction
of the selrecord()'ed selinfo object.
Fix this by adding the seldrain() routine which should be called
before to destroy the selinfo objects (in order to avoid such case),
and fix the present cases where it might have already been called.
Sometimes, the context is safe enough to prevent this type of race,
like it happens in device drivers which installs selinfo objects on
poll callbacks. There, the destruction of the selinfo object happens
at driver detach time, when all the filedescriptors should be already
closed, thus there cannot be a race.
For this case, mfi(4) device driver can be set as an example, as it
implements a full correct logic for preventing this from happening.
Sponsored by: Sandvine Incorporated
Reported by: rstone
Tested by: pluknet
Reviewed by: jhb, kib
Approved by: re (bz)
MFC after: 3 weeks
driver-maintained ifnet fields (such as if_drv_flags).
- Use soft locks as the mutex that protects each interface's knote list
rather than using the global knote list lock. Also, use the softc
for kn_hook instead of the cdev.
- Use mtx_sleep() instead of tsleep() when blocking in the read routines.
This fixes a lost wakeup race.
- Remove D_NEEDGIANT now that the cdevsw routines use the softc lock
where locking is needed.
- Lock IFQ when calculating the result for FIONREAD in tap(4). tun(4)
already did this.
- Remove remaining spl calls.
Submitted by: Marcin Cieslak saper of saper|info (3)
MFC after: 2 weeks
if the interface has such capability. The interface
capability flag indicates whether such capability
exists. This approach is much more backward compatible.
Physical device driver changes will be part of another
commit.
Also updated the ifconfig utility to show the LINKSTATE
capability if present.
Reviewed by: rwatson, imp, juli
MFC after: 3 days
does not set or update the if_link_state variable.
As such RT_LINK_IS_UP() fails for the if_tap interface.
Also, the RT_LINK_IS_UP() needs to bypass all loopback
interfaces because loopback interfaces are considered
up logically as long as the system is running.
This patch fixes the above issues by setting and updating
the if_link_state variable when the tap interface is
opened or closed respectively. Similary approach is
already done in the if_tun device.
MFC after: 3 days
Do not do additional dev_ref() on the newly created interface in the
if_clone create method [1]. This reference is not needed and never
removed, causing struct cdevpriv leakage. Remove the setting of
SI_CHEAPCLONE flag as well, since it is unused.
For dev_clone handlers, create cdevs with the call make_dev_credf(MAKEDEV_REF)
instead of calling make_dev() and then dev_ref(), to avoid a race.
Call drain_dev_clone_events() at the module unload time after dev_clone
handler is deinstalled.
Submitted by: Mikolaj Golub <to.my.trociny gmail com> [1]
MFC after: 1 week
Note that this does not actually enable full-range i/o requests for
64 architectures, and is done now to update KBI only.
Tested by: pho
Reviewed by: jhb, bde (as part of the review of the bigger patch)
vnode interlock to protect the knote fields [1]. The locking assumes
that shared vnode lock is held, thus we get exclusive access to knote
either by exclusive vnode lock protection, or by shared vnode lock +
vnode interlock.
Do not use kl_locked() method to assert either lock ownership or the
fact that curthread does not own the lock. For shared locks, ownership
is not recorded, e.g. VOP_ISLOCKED can return LK_SHARED for the shared
lock not owned by curthread, causing false positives in kqueue subsystem
assertions about knlist lock.
Remove kl_locked method from knlist lock vector, and add two separate
assertion methods kl_assert_locked and kl_assert_unlocked, that are
supposed to use proper asserts. Change knlist_init accordingly.
Add convenience function knlist_init_mtx to reduce number of arguments
for typical knlist initialization.
Submitted by: jhb [1]
Noted by: jhb [2]
Reviewed by: jhb
Tested by: rnoland
no-op's that I inadvertently added. Even if locking is needed in general
for the ioctl's, setting a single long will not need it due to the operation
being atomic.
Reported by: rwatson
have its MTU set higher than 1500 (ETHERMTU). Its new limit is now
65535 as enforced by ifhwioctl() in if.c
This allows a tap(4) device to be added to a bridge, which requires all
interface members to have the same MTU, with an interface configured for
jumbo frames. QEMU may now connect to a network via tap(4) without
requiring the real interface to have its MTU set to 1500 or lower.
Reviewed by: rpaulo, bms
MFC after: 1 week
After I removed all the unit2minor()/minor2unit() calls from the kernel
yesterday, I realised calling minor() everywhere is quite confusing.
Character devices now only have the ability to store a unit number, not
a minor number. Remove the confusion by using dev2unit() everywhere.
This commit could also be considered as a bug fix. A lot of drivers call
minor(), while they should actually be calling dev2unit(). In -CURRENT
this isn't a problem, but it turns out we never had any problem reports
related to that issue in the past. I suspect not many people connect
more than 256 pieces of the same hardware.
Reviewed by: kib
When I changed kern_conf.c three months ago I made device unit numbers
equal to (unneeded) device minor numbers. We used to require
bitshifting, because there were eight bits in the middle that were
reserved for a device major number. Not very long after I turned
dev2unit(), minor(), unit2minor() and minor2unit() into macro's.
The unit2minor() and minor2unit() macro's were no-ops.
We'd better not remove these four macro's from the kernel, because there
is a lot of (external) code that may still depend on them. For now it's
harmless to remove all invocations of unit2minor() and minor2unit().
Reviewed by: kib
Except for the case where we use the cloner library (clone_create() and
friends), there is no reason to enforce a unique device minor number
policy. There are various drivers in the source tree that allocate unr
pools and such to provide minor numbers, without using them themselves.
Because we still need to support unique device minor numbers for the
cloner library, introduce a new flag called D_NEEDMINOR. All cdevsw's
that are used in combination with the cloner library should be marked
with this flag to make the cloning work.
This means drivers can now freely use si_drv0 to store their own flags
and state, making it effectively the same as si_drv1 and si_drv2. We
still keep the minor() and dev2unit() routines around to make drivers
happy.
The NTFS code also used the minor number in its hash table. We should
not do this anymore. If the si_drv0 field would be changed, it would no
longer end up in the same list.
Approved by: philip (mentor)
Make devfs cloning a sysctl/tunable which defaults to on.
If devfs cloning is enabled, only the super-user may create
tun(4)/tap(4)/vmnet(4) instances. Devfs cloning is still enabled by
default; it may be disabled from the loader or via sysctl with
"net.link.tap.devfs_cloning" and "net.link.tun.devfs_cloning".
Disabling its use affects potentially all tun(4)/tap(4) consumers
including OpenSSH, OpenVPN and VMware.
PR: 105228 (potentially also 90413, 105570)
Submitted by: Landon Fuller
Tested by: Andrej Tobola
Approved by: core (rwatson)
MFC after: 4 weeks
of a tap(4) instance, if IFF_PROMISC is not set.
In tap(4), we should emulate the effect IFF_PROMISC would have on
hardware, otherwise we risk introducing layer 2 loops if tap(4) is
used with bridges. This means not even bpf(4) gets to see them.
This patch has been tested in a variety of situations. Multicast and
broadcast frames are correctly allowed through. I have observed this
behaviour causing problems with multiple QEMU instances hosted on
the same FreeBSD machine.
The checks in in ether_demux() [if_ethersubr.c, rev 1.222, line 638]
are insufficient to prevent this bug from occurring, as ifp->if_vlantrunk
will always be NULL for the non-vlan case.
MFC after: 3 weeks
PR: 86429
Submitted by: Pieter de Boer (with changes)
specific privilege names to a broad range of privileges. These may
require some future tweaking.
Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>
we never initialize it to anything else. However, in the case that
m_uiotombuf fails, we return error (effectively reporting success).
This appears to be a relic of an older revision of this file, where
"error" used to be doing something useful. (See revision 1.1, where
error is used in a loop with uiomove() instead of using m_uiotomubf).
So instead on unconditionally reporting success in the case there is
a failure in m_uiotombuf, explicitly return ENOBUFS. While we are
here, garbage collect the error variable since it's no longer required.
MFC after: 2 weeks
mbuf clusters. Add a flags parameter to accept M_PKTHDR and M_EOR mbuf
chain flags. Provide compatibility macro for m_getm() calling m_getm2()
with M_PKTHDR set.
Rewrite m_uiotombuf() to use m_getm2() for mbuf allocation and do the
uiomove() in a tight loop over the mbuf chain. Add a flags parameter to
accept mbuf flags to be passed to m_getm2(). Adjust all callers for the
extra parameter.
Sponsored by: TCP/IP Optimization Fundraise 2005
MFC after: 3 month
ioctls passing integer arguments should use the _IOWINT() macro.
This fixes a lot of ioctl's not working on sparc64, most notable
being keyboard/syscons ioctls.
Full ABI compatibility is provided, with the bonus of fixing the
handling of old ioctls on sparc64.
Reviewed by: bde (with contributions)
Tested by: emax, marius
MFC after: 1 week
for IOCTLs where casting data to intptr_t * isn't the right thing to do
as _IO() isn't used for them but _IOR(..., int)/_IOW(..., int) are (i.e.
for all IOCTLs except VMIO_SIOCSIFFLAGS), fixing tap(4) on big-endian
LP64 machines.
PR: sparc64/98084
OK'ed by: emax
MFC after: 1 week
actually destroyed. Also move call to knlist_init() into tapcreate(). This
should fix panic described in kern/95357.
PR: kern/95357
No response from: freebsd-current@
MFC after: 3 days
K&R style function declarations with ANSI style. Also fix endian bugs
accessing ioctl arguments that are passed by value.
PR: kern/93897
Submitted by: Vilmos Nebehaj < vili at huwico dot hu >
MFC after: 1 week
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.
IFF_DRV_RUNNING, as well as the move from ifnet.if_flags to
ifnet.if_drv_flags. Device drivers are now responsible for
synchronizing access to these flags, as they are in if_drv_flags. This
helps prevent races between the network stack and device driver in
maintaining the interface flags field.
Many __FreeBSD__ and __FreeBSD_version checks maintained and continued;
some less so.
Reviewed by: pjd, bz
MFC after: 7 days
event handler, dev_clone, which accepts a credential argument.
Implementors of the event can ignore it if they're not interested,
and most do. This avoids having multiple event handler types and
fall-back/precedence logic in devfs.
This changes the kernel API for /dev cloning, and may affect third
party packages containg cloning kernel modules.
Requested by: phk
MFC after: 3 days
struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.
This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.
Other changes of note:
- Struct arpcom is no longer referenced in normal interface code.
Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
To enforce this ac_enaddr has been renamed to _ac_enaddr.
- The second argument to ether_ifattach is now always the mac address
from driver private storage rather than sometimes being ac_enaddr.
Reviewed by: sobomax, sam
so if_tap doesn't need to rely on locally-rolled code to do same.
The observable symptom of if_tap's bzero'ing the address details
was a crash in "ifconfig tap0" after an if_tap device was closed.
Reported By: Matti Saarinen (mjsaarin at cc dot helsinki dot fi)
to the mbuf. Offset cannot exceed MHLEN bytes. This is currently used to
fix Ethernet header alignment problem on alpha and sparc64. Also change all
users of m_uiotombuf to pass proper offset.
Reviewed by: jmg, sam
Tested by: Sten Spans "sten AT blinkenlights DOT nl"
MFC after: 1 week
The big lines are:
NODEV -> NULL
NOUDEV -> NODEV
udev_t -> dev_t
udev2dev() -> findcdev()
Various minor adjustments including handling of userland access to kernel
space struct cdev etc.
the tap driver, even with Giant over the cdev operation vector, due to
a non-atomic test-and-set of the si_drv1 field in the dev_t. This bug
exists with Giant under high memory pressure, as malloc() may sleep
in tapcreate(), but is less likely to occur. The resolution will
probably be to cover si_drv1 using the global tapmtx since no softc is
available, but I need to think about this problem more generally
across a range of drivers using si_drv1 in combination with SI_CHEAPCLONE
to defer expensive allocation to open().
Correct what appears to be a bug in the original if_tap implementation,
in which tapopen() will panic if a tap device instance is opened more
than once due to an incorrect assertion -- only triggered if INVARIANTS
is compiled in (i.e., when built into a kernel). Return EBUSY instead.
Expand mtx_lock() coverage using tp->tap_mtx to include tp->ether_addr.
(tap_pid, tap_flags). if_tap should now be entirely MPSAFE.
Committed from: Bamboo house by ocean in Taiwan
Tropical paradise provided by: Chia-liang Kao <clkao@clkao.org>
add tapmtx, which protects globale variables.
Notes:
- The EBUSY check in MOD_UNLOAD may be subject to a race. Moving the
event handler unregister inside the mutex grab may prevent that race.
- Locking of global variables safely is now possible because tapclones
is only modified when the module is loading or unloading, thanks to
phk's recent chang to clone_setup().
- softc locking to follow.