Commit Graph

4512 Commits

Author SHA1 Message Date
Alexander V. Chernikov
f733d9701b Fix default route handling in radix4_lockless algo.
Improve nexthop debugging.

Reported by:	Florian Smeets <flo at smeets.xyz>
2020-12-26 22:51:02 +00:00
Alexander V. Chernikov
4e19e0d92a Use light-weight versions of routing lookup functions in ng_netflow.
Use recently-added combination of `fib[46]_lookup_rt()` which
 returns rtentry & raw nexthop with `rt_get_inet[6]_plen()` which
 returns address/prefix length of prefix inside `rt`.

Add `nhop_select_func()` wrapper around inlined `nhop_select()` to
 allow callers external to the routing subsystem select the proper
 nexthop from the multipath group without including internal headers.

New calls does not require reference counting objects and reduce
 the amount of copied/processed rtentry data.

Differential Revision: https://reviews.freebsd.org/D27675
2020-12-26 11:27:38 +00:00
Alexander V. Chernikov
f5baf8bb12 Add modular fib lookup framework.
This change introduces framework that allows to dynamically
 attach or detach longest prefix match (lpm) lookup algorithms
 to speed up datapath route tables lookups.

Framework takes care of handling initial synchronisation,
 route subscription, nhop/nhop groups reference and indexing,
 dataplane attachments and fib instance algorithm setup/teardown.
Framework features automatic algorithm selection, allowing for
 picking the best matching algorithm on-the-fly based on the
 amount of routes in the routing table.

Currently framework code is guarded under FIB_ALGO config option.
An idea is to enable it by default in the next couple of weeks.

The following algorithms are provided by default:
IPv4:
* bsearch4 (lockless binary search in a special IP array), tailored for
  small-fib (<16 routes)
* radix4_lockless (lockless immutable radix, re-created on every rtable change),
  tailored for small-fib (<1000 routes)
* radix4 (base system radix backend)
* dpdk_lpm4 (DPDK DIR24-8-based lookups), lockless datastrucure, optimized
  for large-fib (D27412)
IPv6:
* radix6_lockless (lockless immutable radix, re-created on every rtable change),
  tailed for small-fib (<1000 routes)
* radix6 (base system radix backend)
* dpdk_lpm6 (DPDK DIR24-8-based lookups), lockless datastrucure, optimized
  for large-fib (D27412)

Performance changes:
Micro benchmarks (I7-7660U, single-core lookups, 2048k dst, code in D27604):
IPv4:
8 routes:
  radix4: ~20mpps
  radix4_lockless: ~24.8mpps
  bsearch4: ~69mpps
  dpdk_lpm4: ~67 mpps
700k routes:
  radix4_lockless: 3.3mpps
  dpdk_lpm4: 46mpps

IPv6:
8 routes:
  radix6_lockless: ~20mpps
  dpdk_lpm6: ~70mpps
100k routes:
  radix6_lockless: 13.9mpps
  dpdk_lpm6: 57mpps

Forwarding benchmarks:
+ 10-15% IPv4 forwarding performance (small-fib, bsearch4)
+ 25% IPv4 forwarding performance (full-view, dpdk_lpm4)
+ 20% IPv6 forwarding performance (full-view, dpdk_lpm6)

Control:
Framwork adds the following runtime sysctls:

List algos
* net.route.algo.inet.algo_list: bsearch4, radix4_lockless, radix4
* net.route.algo.inet6.algo_list: radix6_lockless, radix6, dpdk_lpm6
Debug level (7=LOG_DEBUG, per-route)
net.route.algo.debug_level: 5
Algo selection (currently only for fib 0):
net.route.algo.inet.algo: bsearch4
net.route.algo.inet6.algo: radix6_lockless

Support for manually changing algos in non-default fib will be added
soon. Some sysctl names will be changed in the near future.

Differential Revision: https://reviews.freebsd.org/D27401
2020-12-25 11:33:17 +00:00
Ryan Libby
2fb4a03d55 rtsock: quiet -Wunused-variable in LINT-NOIP kernels
Fixup after r368769 / d68fb8d978.

Reported by:	mjg
Reviewed by:	melifaro
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D27730
2020-12-24 12:34:18 -08:00
Mark Johnston
92be2847e8 rtsock: Avoid copying uninitialized padding bytes
When copying sockaddrs out to userspace, we pad them to a multiple of
the platform alignment (sizeof(long)).  However, some sockaddr sizes,
such as struct sockaddr_dl, are not an integer multiple of the
alignment, so we may end up copying out uninitialized bytes.

Fix this by always bouncing through a pre-zeroed sockaddr_storage.

Reported by:	KASAN
Reviewed by:	melifaro
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D27729
2020-12-23 11:16:40 -05:00
Kristof Provost
1c00efe98e pf: Use counter(9) for pf_state byte/packet tracking
This improves cache behaviour by not writing to the same variable from
multiple cores simultaneously.

pf_state is only used in the kernel, so can be safely modified.

Reviewed by:	Lutz Donnerhacke, philip
MFC after:	1 week
Sponsed by:	Orange Business Services
Differential Revision:	https://reviews.freebsd.org/D27661
2020-12-23 12:03:21 +01:00
Kristof Provost
c3f69af03a pf: Fix unaligned checksum updates
The algorithm we use to update checksums only works correctly if the
updated data is aligned on 16-bit boundaries (relative to the start of
the packet).

Import the OpenBSD fix for this issue.

PR:		240416
Obtained from:	OpenBSD
MFC after:	1 week
Reviewed by:	tuexen (previous version)
Differential Revision:	https://reviews.freebsd.org/D27696
2020-12-23 12:03:20 +01:00
Hans Petter Selasky
ddce63fcb6 Remove not needed variable initialization.
And switch from int to bool while at it.

Reviewed by:	melifaro@
Differential Revision:	https://reviews.freebsd.org/D27725
MFC after:	1 week
Sponsored by:	Mellanox Technologies // NVIDIA Networking
2020-12-23 12:04:46 +01:00
Konstantin Belousov
994e47023a vxlan: stop checking CSUM_ENCAP_VXLAN when converting inner CSUM flags into normal, for decapsulation.
The packet, if processed at this point, was already parsed to be UDP
directed to a vxlan port.

Connect-X 4+ does not provide easy method to infer which parser
processed the packet, so driver cannot set the flag without a lot of
efforts which are only to satisfy the formal requirements.

Reviewed by:	bryanv, np
Sponsored by:	Mellanox Technologies/NVidia Networking
Differential revision:	https://reviews.freebsd.org/D27449
MFC after:	1 week
2020-12-23 10:54:06 +02:00
Alexander V. Chernikov
d68fb8d978 Switch direct rt fields access in rtsock.c to newly-create field acessors.
rtsock code was build around the assumption that each rtentry record
 in the system radix tree is a ready-to-use sockaddr. This assumptions
 turned out to be not quite true:
* masks have their length tweaked, so we have rtsock_fix_netmask() hack
* IPv6 addresses have their scope embedded, so we have another explicit
 deembedding hack.

Change the code to decouple rtentry internals from rtsock code using
 newly-created rtentry accessors. This will allow to eventually eliminate
 both of the hacks and change rtentry dst/mask format.

Differential Revision:	https://reviews.freebsd.org/D27451
2020-12-18 22:00:57 +00:00
Brooks Davis
f3f2ee76ad style(9): Correct whitespace in struct definitions
struct ifconf and struct ifreq use the odd style "struct<tab>foo".
struct ifdrv seems to have tried to follow this but was committed with
spaces in place of most tabs resulting in "struct<space><space>ifdrv".

MFC after:	3 days
2020-12-11 01:00:07 +00:00
Gleb Smirnoff
5ee33a9076 Fixup r368446 with KERN_TLS. 2020-12-08 23:54:09 +00:00
Gleb Smirnoff
e1074ed6a0 The list of ports in configuration path shall be protected by locks,
epoch shall be used only for fast path.  Thus use LAGG_XLOCK() in
lagg_[un]register_vlan.  This fixes sleeping in epoch panic.

PR:		240609
2020-12-08 16:46:00 +00:00
Gleb Smirnoff
87bf9b9cbe Convert LAGG_RLOCK() to NET_EPOCH_ENTER(). No functional changes. 2020-12-08 16:36:46 +00:00
Mark Johnston
c065d4e5e9 iflib: Avoid leaking the freelist bitmaps upon driver detach
Submitted by:	Sai Rajesh Tallamraju <stallamr@netapp.com>
MFC after:	2 weeks
Sponsored by:	NetApp, Inc.
Differential Revision:	https://reviews.freebsd.org/D27342
2020-12-07 14:53:14 +00:00
Mark Johnston
102540192c iflib: Detach tasks upon device registration failure
In some error paths we would fail to detach from the iflib taskqueue
groups.  Also move the detach code into its own subroutine instead of
duplicating it.

Submitted by:	Sai Rajesh Tallamraju <stallamr@netapp.com>
MFC after:	2 weeks
Sponsored by:	NetApp, Inc.
Differential Revision:	https://reviews.freebsd.org/D27342
2020-12-07 14:52:57 +00:00
Alexander V. Chernikov
df9053920f Add IPv4/IPv6 rtentry prefix accessors.
Multiple consumers like ipfw, netflow or new route lookup algorithms
 need to get the prefix data out of struct rtentry.
Instead of providing direct access to the rtentry, create IPv4/IPv6
 accessors to abstract struct rtentry internals and avoid including
 internal routing headers for external consumers.

While here, move struct route_nhop_data to the public header, so external
 customers can actually use lookup functions returning rt&nhop data.

Differential Revision:	https://reviews.freebsd.org/D27416
2020-12-03 22:23:57 +00:00
Kristof Provost
7f883a9b5b net: Revert vnet/epair cleanup race mitigation
Revert the mitigation code for the vnet/epair cleanup race (done in r365457).
r368237 introduced a more reliable fix.

MFC after:	2 weeks
Sponsored by:	Modirum MDPay
2020-12-01 16:34:43 +00:00
Kristof Provost
e133271fc1 if: Fix panic when destroying vnet and epair simultaneously
When destroying a vnet and an epair (with one end in the vnet) we often
panicked. This was the result of the destruction of the epair, which destroys
both ends simultaneously, happening while vnet_if_return() was moving the
struct ifnet to its home vnet. This can result in a freed ifnet being re-added
to the home vnet V_ifnet list. That in turn panics the next time the ifnet is
used.

Prevent this race by ensuring that vnet_if_return() cannot run at the same time
as if_detach() or epair_clone_destroy().

PR:		238870, 234985, 244703, 250870
MFC after:	2 weeks
Sponsored by:	Modirum MDPay
Differential Revision:	https://reviews.freebsd.org/D27378
2020-12-01 16:23:59 +00:00
Alexander V. Chernikov
77df2c21cb Renumber NHR_* flags after NHR_IFAIF removal in r368127.
Suggested by:	rpokala
2020-11-30 21:42:55 +00:00
Alexander V. Chernikov
d1d941c5b9 Remove RADIX_MPATH config option.
ROUTE_MPATH is the new config option controlling new multipath routing
 implementation. Remove the last pieces of RADIX_MPATH-related code and
 the config option.

Reviewed by:	glebius
Differential Revision:	https://reviews.freebsd.org/D27244
2020-11-29 19:43:33 +00:00
Matt Macy
2338da0373 Import kernel WireGuard support
Data path largely shared with the OpenBSD implementation by
Matt Dunwoodie <ncon@nconroy.net>

Reviewed by:	grehan@freebsd.org
MFC after:	1 month
Sponsored by:	Rubicon LLC, (Netgate)
Differential Revision:	https://reviews.freebsd.org/D26137
2020-11-29 19:38:03 +00:00
Alexander V. Chernikov
3b1654cb14 Introduce rib_walk_ext_internal() to allow iteration with rnh pointer.
This solves the case when rib is not yet attached/detached to/from the
 system rib array.

Differential Revision:	https://reviews.freebsd.org/D27406
2020-11-29 13:54:49 +00:00
Alexander V. Chernikov
f47fa26065 Add nhop_ref_any() to unify referencing nhop or nexthop group.
It allows code within routing subsystem to transparently reference nexthops
 and nexthop groups, similar to nhop_free_any(), abstracting ROUTE_MPATH
 details.

Differential Revision:	https://reviews.freebsd.org/D27410
2020-11-29 13:52:06 +00:00
Alexander V. Chernikov
b712e3e343 Refactor fib4/fib6 functions.
No functional changes.

* Make lookup path of fib<4|6>_lookup_debugnet() separate functions
 (fib<46>_lookup_rt()). These will be used in the control plane code
 requiring unlocked radix operations and actual prefix pointer.
* Make lookup part of fib<4|6>_check_urpf() separate functions.
 This change simplifies the switch to alternative lookup implementations,
 which helps algorithmic lookups introduction.
* While here, use static initializers for IPv4/IPv6 keys

Differential Revision:	https://reviews.freebsd.org/D27405
2020-11-29 13:41:49 +00:00
Alexander V. Chernikov
98d5c4e5c8 Add tracking for rib/nhops/nhgrp objects and provide cumulative number accessors.
The resulting KPI can be used by routing table consumers to estimate the required
 scale for route table export.

* Add tracking for rib routes
* Add accessors for number of nexthops/nexthop objects
* Simplify rib_unsubscribe: store rnh we're attached to instead of requiring it up
 again on destruction. This helps in the cases when rnh is not linked yet/already unlinked.

Differential Revision:	https://reviews.freebsd.org/D27404
2020-11-29 13:27:24 +00:00
Alexander V. Chernikov
ef6ef7e5da Add nhgrp_get_idx() as a counterpart for nhop_get_idx().
It allows the routing-related code to reference nexthop groups by index
 instead of storing a pointer.
2020-11-28 15:46:40 +00:00
Alexander V. Chernikov
7a6dc73c98 Cleanup nexthops request flags:
* remove NHR_IFAIF as it was used by previous version of nexthop KPI
* update NHR_REF description
2020-11-28 15:11:59 +00:00
Konstantin Belousov
cd85379104 Make MAXPHYS tunable. Bump MAXPHYS to 1M.
Replace MAXPHYS by runtime variable maxphys. It is initialized from
MAXPHYS by default, but can be also adjusted with the tunable kern.maxphys.

Make b_pages[] array in struct buf flexible.  Size b_pages[] for buffer
cache buffers exactly to atop(maxbcachebuf) (currently it is sized to
atop(MAXPHYS)), and b_pages[] for pbufs is sized to atop(maxphys) + 1.
The +1 for pbufs allow several pbuf consumers, among them vmapbuf(),
to use unaligned buffers still sized to maxphys, esp. when such
buffers come from userspace (*).  Overall, we save significant amount
of otherwise wasted memory in b_pages[] for buffer cache buffers,
while bumping MAXPHYS to desired high value.

Eliminate all direct uses of the MAXPHYS constant in kernel and driver
sources, except a place which initialize maxphys.  Some random (and
arguably weird) uses of MAXPHYS, e.g. in linuxolator, are converted
straight.  Some drivers, which use MAXPHYS to size embeded structures,
get private MAXPHYS-like constant; their convertion is out of scope
for this work.

Changes to cam/, dev/ahci, dev/ata, dev/mpr, dev/mpt, dev/mvs,
dev/siis, where either submitted by, or based on changes by mav.

Suggested by: mav (*)
Reviewed by:	imp, mav, imp, mckusick, scottl (intermediate versions)
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D27225
2020-11-28 12:12:51 +00:00
Kristof Provost
bca0e1d2ac if: Fix non-VIMAGE build
if_link_ifnet() and if_unlink_ifnet() are needed even when VIMAGE is not
enabled.

MFC after:	2 weeks
Sponsored by:	Modirum MDPay
2020-11-25 17:15:24 +00:00
Kristof Provost
a779388f8b if: Protect V_ifnet in vnet_if_return()
When we terminate a vnet (i.e. jail) we move interfaces back to their home
vnet. We need to protect our access to the V_ifnet CK_LIST.

We could enter NET_EPOCH, but if_detach_internal() (called from if_vmove())
waits for net epoch callback completion. That's not possible from NET_EPOCH.
Instead, we take the IFNET_WLOCK, build a list of the interfaces that need to
move and, once we've released the lock, move them back to their home vnet.

We cannot hold the IFNET_WLOCK() during if_vmove(), because that results in a
LOR between ifnet_sx, in_multi_sx and iflib ctx lock.

Separate out moving the ifp into or out of V_ifnet, so we can hold the lock as
we do the list manipulation, but do not hold it as we if_vmove().

Reviewed by:	melifaro
MFC after:	2 weeks
Sponsored by:	Modirum MDPay
Differential Revision:	https://reviews.freebsd.org/D27279
2020-11-25 15:07:22 +00:00
Kristof Provost
a60100fdfc if: Remove ifnet_rwlock
It no longer serves any purpose, as evidenced by the fact that we never take it
without ifnet_sxlock.

Sponsored by:	Modirum MDPay
Differential Revision:	https://reviews.freebsd.org/D27278
2020-11-25 10:56:38 +00:00
Alexander V. Chernikov
7511a63825 Refactor rib iterator functions.
* Make rib_walk() order of arguments consistent with the rest of RIB api
* Add rib_walk_ext() allowing to exec callback before/after iteration.
* Rename rt_foreach_fib_walk_del -> rib_foreach_table_walk_del
* Rename rt_forach_fib_walk -> rib_foreach_table_walk
* Move rib_foreach_table_walk{_del} to route/route_helpers.c
* Slightly refactor rib_foreach_table_walk{_del} to make the implementation
 consistent and prepare for upcoming iterator optimizations.

Differential Revision:	https://reviews.freebsd.org/D27219
2020-11-22 20:21:10 +00:00
Mitchell Horne
70af7ce99a Make net/ifq.h C++ friendly
Don't use "new" as an identifier, and add explicit casts from void *.

As a general policy, FreeBSD doesn't make any C++ compatibility
guarantees for kernel headers like it does for userland, but it is a
small effort to do so in this case, to the benefit of a downstream
consumer (NetApp).

Reviewed by:	rscheff
Sponsored by:	NetApp, Inc.
Sponsored by:	Klara, Inc.
Differential Revision:	https://reviews.freebsd.org/D27286
2020-11-20 14:45:45 +00:00
Andrew Gallatin
8732245d29 LACP: When suppressing distributing, return ENOBUFS
When links come and go, lacp goes into a "suppress distributing" mode
where it drops traffic for 3 seconds. When in this mode, lagg/lacp
historiclally drops traffic with ENETDOWN. That return value causes TCP
to close any connection where it gets that value back from the lower
parts of the stack.  This means that any TCP connection with active
traffic during a 3-second windown when an LACP link comes or goes
would get closed.

TCP treats return values of ENOBUFS as transient errors, and re-schedules
transmission later. So rather than returning ENETDOWN, lets
return ENOBUFS instead.  This allows TCP connections to be preserved.

I've tested this by repeatedly bouncing links on a Netlfix CDN server
under a moderate (20Gb/s) load and overved ENOBUFS reported back to
the TCP stack (as reported by a RACK TCP sysctl).

Reviewed by:	jhb, jtl, rrs
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D27188
2020-11-18 14:55:49 +00:00
Mark Johnston
54bf96fb4f iflib: Free full mbuf chains when draining transmit queues
Submitted by:	Sai Rajesh Tallamraju <stallamr@netapp.com>
Reviewed by:	gallatin, hselasky
MFC after:	1 week
Sponsored by:	NetApp, Inc.
Differential Revision:	https://reviews.freebsd.org/D27179
2020-11-11 18:00:06 +00:00
Andrey V. Elsukov
2f4ffa9f72 Fix possible NULL pointer dereference.
lagg(4) replaces if_output method of its child interfaces and expects
that this method can be called only by child interfaces. But it is
possible that lagg_port_output() could be called by children of child
interfaces. In this case ifnet's if_lagg field is NULL. Add check that
lp is not NULL.

Obtained from:	Yandex LLC
MFC after:	1 week
Sponsored by:	Yandex LLC
2020-11-11 15:53:36 +00:00
Mitchell Horne
4a3fc6e22e Fix definition of rn_addmask()
Add the missing static keyword present in the declaration.

Reviewed by:	melifaro
Sponsored by:	NetApp, Inc.
Sponsored by:	Klara, Inc.
Differential Revision:	https://reviews.freebsd.org/D27024
2020-11-08 19:02:22 +00:00
Alexander V. Chernikov
2d39824195 Switch net.add_addr_allfibs default to 0.
The goal of the fib support is to provide multiple independent
 routing tables, isolated from each other.
net.add_addr_allfibs default tries to shift gears in the opposite
 direction, unconditionally inserting all addresses to all of the fibs.

There are use cases when this is necessary, however this is not a
 default expected behaviour, especially compared to other implementations.

Provide WARNING message for the setups with multiple fibs to notify
 potential users of the feature.

Differential Revision:	https://reviews.freebsd.org/D26076
2020-11-08 18:27:49 +00:00
Alexander V. Chernikov
76e6b37f6b Temporarily revert setting net.add_addr_allfibs to 0.
It accidentally sweeped in r367486.
Revert to allow for proper commit message & warning.
2020-11-08 18:11:12 +00:00
Alexander V. Chernikov
770495f4c0 Fix build broken by r367484: add route_ifaddrs.c.
Pointy hat to: melifaro
Reported by:	jenkins
2020-11-08 13:30:44 +00:00
Alexander V. Chernikov
bad6b23606 Move all ifaddr route creation business logic to net/route/route_ifaddr.c
Differential Revision:	https://reviews.freebsd.org/D26318
2020-11-08 11:12:00 +00:00
Konstantin Belousov
80ba361b2f if_media.c SIOCGMEDIAX handler: improve loop
Stop advancing counter past the current iteration number at the start
of iteration.  This removes the need of subtracting one when
calculating index for copyout, and arguably fixes off-by-one reporting
of copied out elements when copyout failed.

Reviewed by:	hselasky
Sponsored by:	Mellanox Technologies / NVidia Networking
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D27073
2020-11-03 14:33:04 +00:00
Konstantin Belousov
1fbbe9dbf5 net/if_media.c: improve IFMEDIA_DEBUG output.
Use consistent output format for hex.
Print both media and mask where relevant.

Reviewed by:	hselasky
Sponsored by:	Mellanox Technologies/NVidia Networking
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D27034
2020-11-01 16:38:30 +00:00
Konstantin Belousov
e399f19dba Cleanup of net/if_media.c: simplify cleanup loop in ifmedia_removeall().
Reviewed by:	hselasky
Sponsored by:	Mellanox Technologies/NVidia Networking
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D27034
2020-11-01 16:36:21 +00:00
Konstantin Belousov
899322fdfa Cleanup of net/if_media.c: some style.
Reviewed by:	hselasky
Sponsored by:	Mellanox Technologies/NVidia Networking
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D27034
2020-11-01 16:30:17 +00:00
Konstantin Belousov
2193fb16b5 Cleanup of net/if_media.c: switch to ANSI C function definitions.
Reviewed by:	hselasky
Sponsored by:	Mellanox Technologies/NVidia Networking
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D27034
2020-11-01 16:25:35 +00:00
Mitchell Horne
ced0f52457 net: add ETHER_IS_IPV6_MULTICAST
This can be used to detect if an ethernet address is specifically an
IPv6 multicast address, defined in accordance to RFC 2464.

ETHER_IS_MULTICAST is still preferred in the general case.

Reviewed by:	ae
Sponsored by:	NetApp, Inc.
Sponsored by:	Klara, Inc.
Differential Revision:	https://reviews.freebsd.org/D26611
2020-10-30 13:32:58 +00:00
John Baldwin
36e0a362ac Add m_snd_tag_alloc() as a wrapper around if_snd_tag_alloc().
This gives a more uniform API for send tag life cycle management.

Reviewed by:	gallatin, hselasky
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D27000
2020-10-29 23:28:39 +00:00
John Baldwin
521eac97f3 Support hardware rate limiting (pacing) with TLS offload.
- Add a new send tag type for a send tag that supports both rate
  limiting (packet pacing) and TLS offload (mostly similar to D22669
  but adds a separate structure when allocating the new tag type).

- When allocating a send tag for TLS offload, check to see if the
  connection already has a pacing rate.  If so, allocate a tag that
  supports both rate limiting and TLS offload rather than a plain TLS
  offload tag.

- When setting an initial rate on an existing ifnet KTLS connection,
  set the rate in the TCP control block inp and then reset the TLS
  send tag (via ktls_output_eagain) to reallocate a TLS + ratelimit
  send tag.  This allocates the TLS send tag asynchronously from a
  task queue, so the TLS rate limit tag alloc is always sleepable.

- When modifying a rate on a connection using KTLS, look for a TLS
  send tag.  If the send tag is only a plain TLS send tag, assume we
  failed to allocate a TLS ratelimit tag (either during the
  TCP_TXTLS_ENABLE socket option, or during the send tag reset
  triggered by ktls_output_eagain) and ignore the new rate.  If the
  send tag is a ratelimit TLS send tag, change the rate on the TLS tag
  and leave the inp tag alone.

- Lock the inp lock when setting sb_tls_info for a socket send buffer
  so that the routines in tcp_ratelimit can safely dereference the
  pointer without needing to grab the socket buffer lock.

- Add an IFCAP_TXTLS_RTLMT capability flag and associated
  administrative controls in ifconfig(8).  TLS rate limit tags are
  only allocated if this capability is enabled.  Note that TLS offload
  (whether unlimited or rate limited) always requires IFCAP_TXTLS[46].

Reviewed by:	gallatin, hselasky
Relnotes:	yes
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D26691
2020-10-29 00:23:16 +00:00