Commit Graph

369 Commits

Author SHA1 Message Date
John Baldwin
5428776e2c Change vlan interfaces to cope more usefully with the parent interface being
renamed.  Previously the vlan interfaces would lose their configuration as if
the parent interface had been physically removed.  Now vlan interfaces ignore
rename events.
- Add a new ifnet flag (IFF_RENAMING) that is set while an ifnet is being
  renamed.  This flag can be checked in ifnet departure/arrival event
  handlers to treat rename events differently.
- Change the ifnet departure event handler in the if_vlan(4) driver to
  ignore departure events due to a trunk interface being renamed.

Reviewed by:	brooks, rwatson
MFC after:	1 week
2009-12-29 13:35:18 +00:00
John Baldwin
34605f8542 Remove if_timer/if_watchdog now that they are no longer used. The space
used by if_timer is reserved for expanding if_index to an int in the
future.

Reviewed by:	rwatson, brooks
2009-11-30 21:25:57 +00:00
Xin LI
1a9d4dda9b Revert revision 199201 for now as it has introduced a kernel vulnerability
and requires more polishing.
2009-11-12 19:02:10 +00:00
Xin LI
41c8c6e876 Add interface description capability as inspired by OpenBSD.
MFC after:	3 months
2009-11-11 21:30:58 +00:00
Qing Li
46e7f9838b A wrong variable is used when setting up the interface
address route, which broke source address selection in
some code paths.

Submitted by:	noted by bz
Reviewed by:	hrs
MFC after:	immediately
2009-09-20 17:22:19 +00:00
Qing Li
9bb7d0f47a Self pointing routes are installed for configured interface addresses
and address aliases. After an interface is brought down and brought
back up again, those self pointing routes disappeared. This patch
ensures after an interface is brought back up, the loopback routes
are reinstalled properly.

Reviewed by:	bz
MFC after:	immediately
2009-09-15 19:18:34 +00:00
Robert Watson
ed2dabfc68 Add IFNET_HOLD reserved pointer value for the ifindex ifnet array,
which allows an index to be reserved for an ifnet without making
the ifnet available for management operations.  Use this in if_alloc()
while the ifnet lock is released between initial index allocation and
completion of ifnet initialization.

Add ifindex_free() to centralize the implementation of releasing an
ifindex value.  Use in if_free() and if_vmove(), as well as when
releasing a held index in if_alloc().

Reviewed by:	bz
MFC after:	3 days
2009-08-26 11:13:10 +00:00
Robert Watson
61f6986b07 Break out allocation of new ifindex values from if_alloc() and if_vmove(),
and centralize in a single function ifindex_alloc().  Assert the
IFNET_WLOCK, and add missing IFNET_WLOCK in if_alloc().  This does not
close all known races in this code.

Reviewed by:	bz
MFC after:	3 days
2009-08-25 20:21:16 +00:00
Robert Watson
8e937462f4 Make if_grow static -- it's not used outside of if.c, and with the
internals destined to change, it's better if it remains that way.

MFC after:	3 days
2009-08-24 12:52:05 +00:00
Marko Zec
52db6805ea When moving ifnets from one vnet to another, and the ifnet
has ifaddresses of AF_LINK type which thus have an embedded
if_index "backpointer", we must update that if_index backpointer
to reflect the new if_index that our ifnet just got assigned.

This change affects only options VIMAGE builds.

Submitted by:	bz
Reviewed by:	bz
Approved by:	re (rwatson), julian (mentor)
2009-08-24 10:14:09 +00:00
Robert Watson
77dfcdc445 Rework global locks for interface list and index management, correcting
several critical bugs, including race conditions and lock order issues:

Replace the single rwlock, ifnet_lock, with two locks, an rwlock and an
sxlock.  Either can be held to stablize the lists and indexes, but both
are required to write.  This allows the list to be held stable in both
network interrupt contexts and sleepable user threads across sleeping
memory allocations or device driver interactions.  As before, writes to
the interface list must occur from sleepable contexts.

Reviewed by:	bz, julian
MFC after:	3 days
2009-08-23 20:40:19 +00:00
Marko Zec
9abb486279 Appease VNET_DEBUG - in if_vmove we temporarily switch i.e.
recurse from one vnet to another which is OK, so no need
to flood the console with warnings here.

Approved by:	re (rwatson), julian (mentor)
2009-08-14 22:46:45 +00:00
Robert Watson
530c006014 Merge the remainder of kern_vimage.c and vimage.h into vnet.c and
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks.  Minor cleanups are done in the process,
and comments updated to reflect these changes.

Reviewed by:	bz
Approved by:	re (vimage blanket)
2009-08-01 19:26:27 +00:00
Bjoern A. Zeeb
be31e5e7b5 Make the in-kernel logic for the SIOCSIFVNET, SIOCSIFRVNET ioctls
(ifconfig ifN (-)vnet <jname|jid>) work correctly.

Move vi_if_move to if.c and split it up into two functions(*),
one for each ioctl.

In the reclaim case, correctly set the vnet before calling if_vmove.

Instead of silently allowing a move of an interface from the current
vnet to the current vnet, return an error. (*)

There is some duplicate interface name checking before actually moving
the interface between network stacks without locking and thus race
prone. Ideally if_vmove will correctly and automagically handle these
in the future.

Suggested by:	rwatson (*)
Approved by:	re (kib)
2009-07-26 11:29:26 +00:00
Robert Watson
d0728d7174 Introduce and use a sysinit-based initialization scheme for virtual
network stacks, VNET_SYSINIT:

- Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will
  occur each time a network stack is instantiated and destroyed.  In the
  !VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT.
  For the VIMAGE case, we instead use SYSINIT's to track their order and
  properties on registration, using them for each vnet when created/
  destroyed, or immediately on module load for already-started vnets.
- Remove vnet_modinfo mechanism that existed to serve this purpose
  previously, as well as its dependency scheme: we now just use the
  SYSINIT ordering scheme.
- Implement VNET_DOMAIN_SET() to allow protocol domains to declare that
  they want init functions to be called for each virtual network stack
  rather than just once at boot, compiling down to DOMAIN_SET() in the
  non-VIMAGE case.
- Walk all virtualized kernel subsystems and make use of these instead
  of modinfo or DOMAIN_SET() for init/uninit events.  In some cases,
  convert modular components from using modevent to using sysinit (where
  appropriate).  In some cases, do minor rejuggling of SYSINIT ordering
  to make room for or better manage events.

Portions submitted by:	jhb (VNET_SYSINIT), bz (cleanup)
Discussed with:		jhb, bz, julian, zec
Reviewed by:		bz
Approved by:		re (VIMAGE blanket)
2009-07-23 20:46:49 +00:00
Robert Watson
006e9db452 Normalize field naming for struct vnet, fix two debugging printfs that
print them.

Reviewed by:	bz
Approved by:	re (kensmith, kib)
2009-07-19 17:40:45 +00:00
Robert Watson
5ee847d3ac Reimplement and/or implement vnet list locking by replacing a mostly
unused custom mutex/condvar-based sleep locks with two locks: an
rwlock (for non-sleeping use) and sxlock (for sleeping use).  Either
acquired for read is sufficient to stabilize the vnet list, but both
must be acquired for write to modify the list.

Replace previous no-op read locking macros, used in various places
in the stack, with actual locking to prevent race conditions.  Callers
must declare when they may perform unbounded sleeps or not when
selecting how to lock.

Refactor vnet sysinits so that the vnet list and locks are initialized
before kernel modules are linked, as the kernel linker will use them
for modules loaded by the boot loader.

Update various consumers of these KPIs based on whether they may sleep
or not.

Reviewed by:	bz
Approved by:	re (kib)
2009-07-19 14:20:53 +00:00
Jamie Gritton
7afcbc18b3 Remove the interim vimage containers, struct vimage and struct procg,
and the ioctl-based interface that supported them.

Approved by:	re (kib), bz (mentor)
2009-07-17 14:48:21 +00:00
Robert Watson
1e77c1056a Remove unused VNET_SET() and related macros; only VNET_GET() is
ever actually used.  Rename VNET_GET() to VNET() to shorten
variable references.

Discussed with:	bz, julian
Reviewed by:	bz
Approved by:	re (kensmith, kib)
2009-07-16 21:13:04 +00:00
Robert Watson
eddfbb763d Build on Jeff Roberson's linker-set based dynamic per-CPU allocator
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator.  Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...).  This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack.  Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory.  Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy.  Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address.  When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by:  bz
Reviewed by:            bz, zec
Discussed with:         gnn, jamie, jeff, jhb, julian, sam
Suggested by:           peter
Approved by:            re (kensmith)
2009-07-14 22:48:30 +00:00
Brooks Davis
6cb7f168db Remove support for the /dev/net/* per-interface devices. They serve
little purpose and are unused in the base system.

The IOCTL functionality is entirely duplicated and routing sockets
provide a richer interface than the kqueue functionality.

Further, it is not practical for these devices to be made sensible in
the face of VIMAGE.

Bump __FreeBSD_version on the off chance that there is any code out
there that actually uses this stuff.

Reviewed by:	rwatson
Discussed with:	bz, zec
Approved by:	re@ (kensmith)
2009-06-29 19:46:29 +00:00
Robert Watson
395cbe82d2 Remove unnecessary include of kdb.h that snuck in during ifaddr refcount
work.

Reported by:	pluknet <pluknet at gmail.com>
Approved by:	re (kib)
2009-06-27 10:30:28 +00:00
Robert Watson
f9ef96ca71 Define four wrapper functions for interface address locking,
if_addr_rlock() and if_addr_runlock() for regular address lists, and
if_maddr_rlock() and if_maddr_runlock() for multicast address lists.

We will use these in various kernel modules to avoid encoding specific
type and locking strategy information into modules that currently use
IF_ADDR_LOCK() and IF_ADDR_UNLOCK() directly.

MFC after:	6 weeks
2009-06-26 00:36:47 +00:00
Robert Watson
3baaf2974d In if_setlladdr(), use IF_ADDR_LOCK() and ifaddr references to improve
the safety of link layer address manipulation.

MFC after:	6 weeks
2009-06-24 10:36:48 +00:00
Robert Watson
8c0fec805f Modify most routines returning 'struct ifaddr *' to return references
rather than pointers, requiring callers to properly dispose of those
references.  The following routines now return references:

  ifaddr_byindex
  ifa_ifwithaddr
  ifa_ifwithbroadaddr
  ifa_ifwithdstaddr
  ifa_ifwithnet
  ifaof_ifpforaddr
  ifa_ifwithroute
  ifa_ifwithroute_fib
  rt_getifa
  rt_getifa_fib
  IFP_TO_IA
  ip_rtaddr
  in6_ifawithifp
  in6ifa_ifpforlinklocal
  in6ifa_ifpwithaddr
  in6_ifadd
  carp_iamatch6
  ip6_getdstifaddr

Remove unused macro which didn't have required referencing:

  IFP_TO_IA6

This closes many small races in which changes to interface
or address lists while an ifaddr was in use could lead to use of freed
memory (etc).  In a few cases, add missing if_addr_list locking
required to safely acquire references.

Because of a lack of deep copying support, we accept a race in which
an in6_ifaddr pointed to by mbuf tags and extracted with
ip6_getdstifaddr() doesn't hold a reference while in transmit.  Once
we have mbuf tag deep copy support, this can be fixed.

Reviewed by:	bz
Obtained from:	Apple, Inc. (portions)
MFC after:	6 weeks (portions)
2009-06-23 20:19:09 +00:00
Bjoern A. Zeeb
a877d0cffa Remove duplicate #include <net/route.h> from the middle of the file. 2009-06-23 13:16:16 +00:00
Bjoern A. Zeeb
b58ea5f310 Move virtualization of routing related variables into their own
Vimage module, which had been there already but now is stateful.

All variables are now file local; so this further limits the global
spreading of routing related things throughout the kernel.

Add a missing function local variable in case of MPATHing.

Reviewed by:	zec
2009-06-22 17:48:16 +00:00
Robert Watson
8896f83a58 Add a new function, ifa_ifwithaddr_check(), which rather than returning
a pointer to an ifaddr matching the passed socket address, returns a
boolean indicating whether one was present.  In the (near) future,
ifa_ifwithaddr() will return a referenced ifaddr rather than a raw
ifaddr pointer, and the new wrapper will allow callers that care only
about the boolean condition to avoid having to free that reference.

MFC after:	3 weeks
2009-06-22 10:59:34 +00:00
Bjoern A. Zeeb
bed56bb51b After the update to fxp(4) in r194573 we should no longer need
this DELAY(100) hack introduced in r56938.

Thanks to:	yongari
MFC after:	6 weeks
X-MFC note:	not before the fxp(4) changes
2009-06-22 10:27:20 +00:00
Robert Watson
1099f828b3 Clean up common ifaddr management:
- Unify reference count and lock initialization in a single function,
  ifa_init().
- Move tear-down from a macro (IFAFREE) to a function ifa_free().
- Move reference count bump from a macro (IFAREF) to a function ifa_ref().
- Instead of using a u_int protected by a mutex to refcount(9) for
  reference count management.

The ifa_mtx is now used for exactly one ioctl, and possibly should be
removed.

MFC after:	3 weeks
2009-06-21 19:30:33 +00:00
Roman Divacky
e40bae9a45 Switch cmd argument to u_long. This matches what if_ethersubr.c does and
allows the code to compile cleanly on amd64 with clang.

Reviewed by:	rwatson
Approved by:	ed (mentor)
2009-06-21 10:29:31 +00:00
Sam Leffler
d659538f72 r193336 moved ifq_detach to if_free which broke if_alloc followed
by if_free (w/o doing if_attach); move ifq_attach to if_alloc and
rename ifq_attach/detach to ifq_init/ifq_delete to better identify
their purpose

Reviewed by:	jhb, kmacy
2009-06-15 19:50:03 +00:00
Jamie Gritton
679e13901c Manage vnets via the jail system. If a jail is given the boolean
parameter "vnet" when it is created, a new vnet instance will be created
along with the jail.  Networks interfaces can be moved between prisons
with an ioctl similar to the one that moves them between vimages.
For now vnets will co-exist under both jails and vimages, but soon
struct vimage will be going away.

Reviewed by:	zec, julian
Approved by:	bz (mentor)
2009-06-15 18:59:29 +00:00
Bjoern A. Zeeb
259d2d5431 carp(4) allows people to share a set of IP addresses and can only
use IPv4/v6 for inter-node communication (according to my reading).

Properly wrap the carp callouts in INET || INET6 and refelect this
in sys/conf/files as well.  While in theory this should be ok,
it might be a bit optimistic to think that carp could build with
inet6 only[1].

Discussed with:		mlaier [1]
2009-06-11 10:26:38 +00:00
Konstantin Belousov
d8b0556c6d Adapt vfs kqfilter to the shared vnode lock used by zfs write vop. Use
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
2009-06-10 20:59:32 +00:00
Bjoern A. Zeeb
8d8bc0182e After r193232 rt_tables in vnet.h are no longer indirectly dependent on
the ROUTETABLES kernel option thus there is no need to include opt_route.h
anymore in all consumers of vnet.h and no longer depend on it for module
builds.

Remove the hidden include in flowtable.h as well and leave the two
explicit #includes in ip_input.c and ip_output.c.
2009-06-08 19:57:35 +00:00
Marko Zec
bc29160df3 Introduce an infrastructure for dismantling vnet instances.
Vnet modules and protocol domains may now register destructor
functions to clean up and release per-module state.  The destructor
mechanisms can be triggered by invoking "vimage -d", or a future
equivalent command which will be provided via the new jail framework.

While this patch introduces numerous placeholder destructor functions,
many of those are currently incomplete, thus leaking memory or (even
worse) failing to stop all running timers.  Many of such issues are
already known and will be incrementaly fixed over the next weeks in
smaller incremental commits.

Apart from introducing new fields in structs ifnet, domain, protosw
and vnet_net, which requires the kernel and modules to be rebuilt, this
change should have no impact on nooptions VIMAGE builds, since vnet
destructors can only be called in VIMAGE kernels.  Moreover,
destructor functions should be in general compiled in only in
options VIMAGE builds, except for kernel modules which can be safely
kldunloaded at run time.

Bump __FreeBSD_version to 800097.
Reviewed by:	bz, julian
Approved by:	rwatson, kib (re), julian (mentor)
2009-06-08 17:15:40 +00:00
Robert Watson
bcf11e8d00 Move "options MAC" from opt_mac.h to opt_global.h, as it's now in GENERIC
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.

Discussed with:	pjd
2009-06-05 14:55:22 +00:00
Sam Leffler
c9dd371765 move ifq_detach from if_detach to if_free; this permits callers to
reference if_snd in the period between detach+free which helps simplify
detach code

Reviewed by:	jhb, rwatson
2009-06-02 18:53:21 +00:00
Bjoern A. Zeeb
c2c2a7c11e Convert the two dimensional array to be malloced and introduce
an accessor function to get the correct rnh pointer back.

Update netstat to get the correct pointer using kvm_read()
as well.

This not only fixes the ABI problem depending on the kernel
option but also permits the tunable to overwrite the kernel
option at boot time up to MAXFIBS, enlarging the number of
FIBs without having to recompile. So people could just use
GENERIC now.

Reviewed by:	julian, rwatson, zec
X-MFC:		not possible
2009-06-01 15:49:42 +00:00
Marko Zec
feb08d06b9 Introduce an interm userland-kernel API for creating vnets and
assigning ifnets from one vnet to another.  Deletion of vnets is not
yet supported.

The interface is implemented as an ioctl extension so that no syscalls
had to be introduced.  This should be acceptable given that the new
interface will be used for a short / interim period only, until the
new jail management framwork gains the capability of managing vnets.
This method for managing vimages / vnets has been in use for the past
7 years without any observable issues.

The userland tool to be used in conjunction with the interim API can be
found in p4: //depot/projects/vimage-commit2/src/usr.sbin/vimage/... and
will most probably never get commited to svn.

While here, bump copyright notices in kern_vimage.c and vimage.h to
cover work done in year 2009.

Approved by:	julian (mentor)
Discussed with:	bz, rwatson
2009-05-31 12:10:04 +00:00
Marko Zec
67da1f3d8d Set ifp->if_afdata_initialized to 0 while holding IF_AFDATA_LOCK on ifp,
not after the lock has been released.

Reviewed by:	bz
Discussed with:	rwatson
2009-05-22 22:22:21 +00:00
Marko Zec
e0c14af9b3 Introduce the if_vmove() function, which will be used in the future
for reassigning ifnets from one vnet to another.

if_vmove() works by calling a restricted subset of actions normally
executed by if_detach() on an ifnet in the current vnet, and then
switches to the target vnet and executes an appropriate subset of
if_attach() actions there.

if_attach() and if_detach() have become wrapper functions around
if_attach_internal() and if_detach_internal(), where the later
variants have an additional argument, a flag indicating whether a
full attach or detach sequence is to be executed, or only a
restricted subset suitable for moving an ifnet from one vnet to
another.  Hence, if_vmove() will not call if_detach() and if_attach()
directly, but will call the if_detach_internal() and
if_attach_internal() variants instead, with the vmove flag set.

While here, staticize ifnet_setbyindex() since it is not referenced
from outside of sys/net/if.c.

Also rename ifccnt field in struct vimage to ifcnt, and do some minor
whitespace garbage collection where appropriate.

This change should have no functional impact on nooptions VIMAGE kernel
builds.

Reviewed by:	bz, rwatson, brooks?
Approved by:	julian (mentor)
2009-05-22 22:09:00 +00:00
Marko Zec
21ca7b57bd Change the curvnet variable from a global const struct vnet *,
previously always pointing to the default vnet context, to a
dynamically changing thread-local one.  The currvnet context
should be set on entry to networking code via CURVNET_SET() macros,
and reverted to previous state via CURVNET_RESTORE().  Recursions
on curvnet are permitted, though strongly discuouraged.

This change should have no functional impact on nooptions VIMAGE
kernel builds, where CURVNET_* macros expand to whitespace.

The curthread->td_vnet (aka curvnet) variable's purpose is to be an
indicator of the vnet context in which the current network-related
operation takes place, in case we cannot deduce the current vnet
context from any other source, such as by looking at mbuf's
m->m_pkthdr.rcvif->if_vnet, sockets's so->so_vnet etc.  Moreover, so
far curvnet has turned out to be an invaluable consistency checking
aid: it helps to catch cases when sockets, ifnets or any other
vnet-aware structures may have leaked from one vnet to another.

The exact placement of the CURVNET_SET() / CURVNET_RESTORE() macros
was a result of an empirical iterative process, whith an aim to
reduce recursions on CURVNET_SET() to a minimum, while still reducing
the scope of CURVNET_SET() to networking only operations - the
alternative would be calling CURVNET_SET() on each system call entry.
In general, curvnet has to be set in three typicall cases: when
processing socket-related requests from userspace or from within the
kernel; when processing inbound traffic flowing from device drivers
to upper layers of the networking stack, and when executing
timer-driven networking functions.

This change also introduces a DDB subcommand to show the list of all
vnet instances.

Approved by:	julian (mentor)
2009-05-05 10:56:12 +00:00
Marko Zec
f6dfe47a14 Permit buiding kernels with options VIMAGE, restricted to only a single
active network stack instance.  Turning on options VIMAGE at compile
time yields the following changes relative to default kernel build:

1) V_ accessor macros for virtualized variables resolve to structure
fields via base pointers, instead of being resolved as fields in global
structs or plain global variables.  As an example, V_ifnet becomes:

    options VIMAGE:          ((struct vnet_net *) vnet_net)->_ifnet
    default build:           vnet_net_0._ifnet
    options VIMAGE_GLOBALS:  ifnet

2) INIT_VNET_* macros will declare and set up base pointers to be used
by V_ accessor macros, instead of resolving to whitespace:

    INIT_VNET_NET(ifp->if_vnet); becomes

    struct vnet_net *vnet_net = (ifp->if_vnet)->mod_data[VNET_MOD_NET];

3) Memory for vnet modules registered via vnet_mod_register() is now
allocated at run time in sys/kern/kern_vimage.c, instead of per vnet
module structs being declared as globals.  If required, vnet modules
can now request the framework to provide them with allocated bzeroed
memory by filling in the vmi_size field in their vmi_modinfo structures.

4) structs socket, ifnet, inpcbinfo, tcpcb and syncache_head are
extended to hold a pointer to the parent vnet.  options VIMAGE builds
will fill in those fields as required.

5) curvnet is introduced as a new global variable in options VIMAGE
builds, always pointing to the default and only struct vnet.

6) struct sysctl_oid has been extended with additional two fields to
store major and minor virtualization module identifiers, oid_v_subs and
oid_v_mod.  SYSCTL_V_* family of macros will fill in those fields
accordingly, and store the offset in the appropriate vnet container
struct in oid_arg1.
In sysctl handlers dealing with virtualized sysctls, the
SYSCTL_RESOLVE_V_ARG1() macro will compute the address of the target
variable and make it available in arg1 variable for further processing.

Unused fields in structs vnet_inet, vnet_inet6 and vnet_ipfw have
been deleted.

Reviewed by:	bz, rwatson
Approved by:	julian (mentor)
2009-04-30 13:36:26 +00:00
Robert Watson
8bd015a1ca As with ifnet_byindex_ref(), don't return IFF_DYING interfaces from
ifunit_ref().  ifunit() continues to return them.

MFC after:	3 weeks
2009-04-23 15:56:01 +00:00
Robert Watson
6064c5d362 Add ifunit_ref(), a version of ifunit(), that returns not just an
interface pointer, but also a reference to it.

Modify ifioctl() to use ifunit_ref(), holding the reference until
all ioctls, etc, have completed.

This closes a class of reader-writer races in which interfaces
could be removed during long-running ioctls, leading to crashes.
Many other consumers of ifunit() should now use ifunit_ref() to
avoid similar races.

MFC after:	3 weeks
2009-04-23 13:08:47 +00:00
Robert Watson
111c6b617b During if_detach(), invoke if_dead() to set the ifnet's function
pointers to "dead" implementations that no-op rather than invoking
the device driver.  This would generally be unexpected and
possibly quite badly handled by most device drivers after
if_detach() has completed.

Reviewed by:	bms
MFC after:	3 weeks
2009-04-23 11:51:53 +00:00
Robert Watson
d6f157ea9a Move portions of data structure initialization from if_attach() to
if_alloc(), and portions of data structure destruction from if_detach()
to if_free().  These changes leave more of the struct ifnet in a
safe-to-access condition between alloc and attach, and between detach
and free, and focus on attach/detach as stack usage events rather than
data structure initialization.

Affected fields include the linkstate task queue, if_afdata lock,
address lists, kqueue state, and MAC labels.  ifq_attach() ifq_detach()
are not moved as ifq_attach() may use a queue length set by the device
driver between if_alloc() and if_attach().

MFC after:	3 weeks
2009-04-23 10:59:40 +00:00
Robert Watson
242a8e72eb Add a new interface flag, IFF_DYING, which is set when a device driver
calls if_free(), and remains set if the refcount is elevated.  IF_DYING
skips the bit in the if_flags bitmask previously used by IFF_NEEDSGIANT,
so that an MFC can be done without changing which bit is used, as
IFF_NEEDSGIANT is still present in 7.x.

ifnet_byindex_ref() checks for IFF_DYING and returns NULL if it is set,
preventing new references from by acquired by index, preventing
monitoring sysctls from seeing it.  Other lookup mechanisms currently
do not check IFF_DYING, but may need to in the future.

MFC after:	3 weeks
2009-04-23 09:32:30 +00:00