Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

This batch contains Netfilter updates for net-next:

1) Add nft_setelem_parse_key() helper function.

2) Add NFTA_SET_ELEM_KEY_END to specify a range with one single element.

3) Add NFTA_SET_DESC_CONCAT to describe the set element concatenation,
   from Stefano Brivio.

4) Add bitmap_cut() to copy n-bits from source to destination,
   from Stefano Brivio.

5) Add set to match on arbitrary concatenations, from Stefano Brivio.

6) Add selftest for this new set type. An extract of Stefano's
   description follows:

"Existing nftables set implementations allow matching entries with
interval expressions (rbtree), e.g. 192.0.2.1-192.0.2.4, entries
specifying field concatenation (hash, rhash), e.g. 192.0.2.1:22,
but not both.

In other words, none of the set types allows matching on range
expressions for more than one packet field at a time, such as ipset
does with types bitmap:ip,mac, and, to a more limited extent
(netmasks, not arbitrary ranges), with types hash:net,net,
hash:net,port, hash:ip,port,net, and hash:net,port,net.

As a pure hash-based approach is unsuitable for matching on ranges,
and "proxying" the existing red-black tree type looks impractical as
elements would need to be shared and managed across all employed
trees, this new set implementation intends to fill the functionality
gap by employing a relatively novel approach.

The fundamental idea, illustrated in deeper detail in patch 5/9, is to
use lookup tables classifying a small number of grouped bits from each
field, and map the lookup results in a way that yields a verdict for
the full set of specified fields.

The grouping bit aspect is loosely inspired by the Grouper algorithm,
by Jay Ligatti, Josh Kuhn, and Chris Gage (see patch 5/9 for the full
reference).

A reference, stand-alone implementation of the algorithm itself is
available at:
        https://pipapo.lameexcu.se

Some notes about possible future optimisations are also mentioned
there. This algorithm reduces the matching problem to, essentially,
a repetitive sequence of simple bitwise operations, and is
particularly suitable to be optimised by leveraging SIMD instruction
sets."
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This test covers functionality and stability of the newly added
nftables set implementation supporting concatenation of ranged
fields.

For some selected set expression types, test:
- correctness, by checking that packets match or don't
- concurrency, by attempting races between insertion, deletion, lookup
- timeout feature, checking that packets don't match expired entries

and (roughly) estimate matching rates, comparing to baselines for
simple drop on netdev ingress hook and for hash and rbtrees sets.

In order to send packets, this needs one of sendip, netcat or bash.
To flood with traffic, iperf3, iperf and netperf are supported. For
performance measurements, this relies on the sample pktgen script
pktgen_bench_xmit_mode_netif_receive.sh.

If none of the tools suitable for a given test are available, specific
tests will be skipped.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

This new set type allows for intervals in concatenated fields,
which are expressed in the usual way, that is, simple byte
concatenation with padding to 32 bits for single fields, and
given as ranges by specifying start and end elements containing,
each, the full concatenation of start and end values for the
single fields.

Ranges are expanded to composing netmasks, for each field: these
are inserted as rules in per-field lookup tables. Bits to be
classified are divided in 4-bit groups, and for each group, the
lookup table contains 4^2 buckets, representing all the possible
values of a bit group. This approach was inspired by the Grouper
algorithm:
	http://www.cse.usf.edu/~ligatti/projects/grouper/

Matching is performed by a sequence of AND operations between
bucket values, with buckets selected according to the value of
packet bits, for each group. The result of this sequence tells
us which rules matched for a given field.

In order to concatenate several ranged fields, per-field rules
are mapped using mapping arrays, one per field, that specify
which rules should be considered while matching the next field.
The mapping array for the last field contains a reference to
the element originally inserted.

The notes in nft_set_pipapo.c cover the algorithm in deeper
detail.

A pure hash-based approach is of no use here, as ranges need
to be classified. An implementation based on "proxying" the
existing red-black tree set type, creating a tree for each
field, was considered, but deemed impractical due to the fact
that elements would need to be shared between trees, at least
as long as we want to keep UAPI changes to a minimum.

A stand-alone implementation of this algorithm is available at:
	https://pipapo.lameexcu.se
together with notes about possible future optimisations
(in pipapo.c).

This algorithm was designed with data locality in mind, and can
be highly optimised for SIMD instruction sets, as the bulk of
the matching work is done with repetitive, simple bitwise
operations.

At this point, without further optimisations, nft_concat_range.sh
reports, for one AMD Epyc 7351 thread (2.9GHz, 512 KiB L1D$, 8 MiB
L2$):

TEST: performance
  net,port                                                      [ OK ]
    baseline (drop from netdev hook):              10190076pps
    baseline hash (non-ranged entries):             6179564pps
    baseline rbtree (match on first field only):    2950341pps
    set with  1000 full, ranged entries:            2304165pps
  port,net                                                      [ OK ]
    baseline (drop from netdev hook):              10143615pps
    baseline hash (non-ranged entries):             6135776pps
    baseline rbtree (match on first field only):    4311934pps
    set with   100 full, ranged entries:            4131471pps
  net6,port                                                     [ OK ]
    baseline (drop from netdev hook):               9730404pps
    baseline hash (non-ranged entries):             4809557pps
    baseline rbtree (match on first field only):    1501699pps
    set with  1000 full, ranged entries:            1092557pps
  port,proto                                                    [ OK ]
    baseline (drop from netdev hook):              10812426pps
    baseline hash (non-ranged entries):             6929353pps
    baseline rbtree (match on first field only):    3027105pps
    set with 30000 full, ranged entries:             284147pps
  net6,port,mac                                                 [ OK ]
    baseline (drop from netdev hook):               9660114pps
    baseline hash (non-ranged entries):             3778877pps
    baseline rbtree (match on first field only):    3179379pps
    set with    10 full, ranged entries:            2082880pps
  net6,port,mac,proto                                           [ OK ]
    baseline (drop from netdev hook):               9718324pps
    baseline hash (non-ranged entries):             3799021pps
    baseline rbtree (match on first field only):    1506689pps
    set with  1000 full, ranged entries:             783810pps
  net,mac                                                       [ OK ]
    baseline (drop from netdev hook):              10190029pps
    baseline hash (non-ranged entries):             5172218pps
    baseline rbtree (match on first field only):    2946863pps
    set with  1000 full, ranged entries:            1279122pps

v4:
 - fix build for 32-bit architectures: 64-bit division needs
   div_u64() (kbuild test robot <lkp@intel.com>)
v3:
 - rework interface for field length specification,
   NFT_SET_SUBKEY disappears and information is stored in
   description
 - remove scratch area to store closing element of ranges,
   as elements now come with an actual attribute to specify
   the upper range limit (Pablo Neira Ayuso)
 - also remove pointer to 'start' element from mapping table,
   closing key is now accessible via extension data
 - use bytes right away instead of bits for field lengths,
   this way we can also double the inner loop of the lookup
   function to take care of upper and lower bits in a single
   iteration (minor performance improvement)
 - make it clearer that set operations are actually atomic
   API-wise, but we can't e.g. implement flush() as one-shot
   action
 - fix type for 'dup' in nft_pipapo_insert(), check for
   duplicates only in the next generation, and in general take
   care of differentiating generation mask cases depending on
   the operation (Pablo Neira Ayuso)
 - report C implementation matching rate in commit message, so
   that AVX2 implementation can be compared (Pablo Neira Ayuso)
v2:
 - protect access to scratch maps in nft_pipapo_lookup() with
   local_bh_disable/enable() (Florian Westphal)
 - drop rcu_read_lock/unlock() from nft_pipapo_lookup(), it's
   already implied (Florian Westphal)
 - explain why partial allocation failures don't need handling
   in pipapo_realloc_scratch(), rename 'm' to clone and update
   related kerneldoc to make it clear we're not operating on
   the live copy (Florian Westphal)
 - add expicit check for priv->start_elem in
   nft_pipapo_insert() to avoid ending up in nft_pipapo_walk()
   with a NULL start element, and also zero it out in every
   operation that might make it invalid, so that insertion
   doesn't proceed with an invalid element (Florian Westphal)
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

The new bitmap function bitmap_cut() copies bits from source to
destination by removing the region specified by parameters first
and cut, and remapping the bits above the cut region by right
shifting them.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Introduce a new nested netlink attribute, NFTA_SET_DESC_CONCAT, used
to specify the length of each field in a set concatenation.

This allows set implementations to support concatenation of multiple
ranged items, as they can divide the input key into matching data for
every single field. Such set implementations would be selected as
they specify support for NFT_SET_INTERVAL and allow desc->field_count
to be greater than one. Explicitly disallow this for nft_set_rbtree.

In order to specify the interval for a set entry, userspace would
include in NFTA_SET_DESC_CONCAT attributes field lengths, and pass
range endpoints as two separate keys, represented by attributes
NFTA_SET_ELEM_KEY and NFTA_SET_ELEM_KEY_END.

While at it, export the number of 32-bit registers available for
packet matching, as nftables will need this to know the maximum
number of field lengths that can be specified.

For example, "packets with an IPv4 address between 192.0.2.0 and
192.0.2.42, with destination port between 22 and 25", can be
expressed as two concatenated elements:

  NFTA_SET_ELEM_KEY:            192.0.2.0 . 22
  NFTA_SET_ELEM_KEY_END:        192.0.2.42 . 25

and NFTA_SET_DESC_CONCAT attribute would contain:

  NFTA_LIST_ELEM
    NFTA_SET_FIELD_LEN:		4
  NFTA_LIST_ELEM
    NFTA_SET_FIELD_LEN:		2

v4: No changes
v3: Complete rework, NFTA_SET_DESC_CONCAT instead of NFTA_SET_SUBKEY
v2: No changes
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Add NFTA_SET_ELEM_KEY_END attribute to convey the closing element of the
interval between kernel and userspace.

This patch also adds the NFT_SET_EXT_KEY_END extension to store the
closing element value in this interval.

v4: No changes
v3: New patch

[sbrivio: refactor error paths and labels; add corresponding
  nft_set_ext_type for new key; rebase]
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Add helper function to parse the set element key netlink attribute.

v4: No changes
v3: New patch

[sbrivio: refactor error paths and labels; use NFT_DATA_VALUE_MAXLEN
  instead of sizeof(*key) in helper, value can be longer than that;
  rebase]
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Using IPv6 flow-label to swiftly route around avoid congested or
disconnected network path can greatly improve TCP reliability.

This patch adds SNMP counters and a OPT_STATS counter to track both
host-level and connection-level statistics. Network administrators
can use these counters to evaluate the impact of this new ability better.

Export count for rehash attempts to
1) two SNMP counters: TcpTimeoutRehash (rehash due to timeouts),
   and TcpDuplicateDataRehash (rehash due to receiving duplicate
   packets)
2) Timestamping API SOF_TIMESTAMPING_OPT_STATS.
Signed-off-by: Abdul Kabbani <akabbani@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Kevin(Yudong) Yang <yyd@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Julian Wiedmann says:

====================
s390/qeth: updates 2020-01-25

please apply the following patch series for qeth to your net-next tree.

This brings a number of cleanups for the init/teardown code paths.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

qeth_l?_stop_card() is _never_ called while in HARDSETUP state, and
there's no other usage of the card state that relies on the
DOWN -> HARDSETUP -> SOFTSETUP transition.

As related cleanup, remove the check in qeth_realloc_buffer_pool() as it
is already done by the callers.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When data is received on the READ channel, the matching logic for cmds
that are waiting for a reply is currently hard-coded into the channel's
main IO callback.
Move this into a per-cmd callback, so that we can apply custom matching
logic for each individual cmd.

This also allows us to remove the coarse-grained check for unexpected
non-IPA replies, since they will no longer match against _all_ pending
cmds.

Note that IDX cmds use _no_ matcher, since their reply is synchronously
received as part of the cmd's IO.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Large parts of the online/offline code are identical now, and cleaning
up the remaining stuff is easier with a shared core.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Move some duplicated logic into a shared code path.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qeth_l2_setup_bridgeport_attrs() is entirely unrelated to sysfs
functionality, move it where it belongs.
While at it merge all the bridgeport-specific code in the set-online
path together.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
100GbE Intel Wired LAN Driver Updates 2020-01-25

This series contains updates to the ice driver to add support for RSS.

Henry and Tony enable the driver to write the filtering hardware tables
to allow for changing of RSS rules, also introduced and initialized the
structures for storing the configuration.  Then followed it up by
creating an extraction sequence based on the packet header protocols to
be programmed.  Next was storing the TCAM entry with the profile data
and VSI group in the respective software structures.

Md Fahad sets up the configuration to support RSS tables for the virtual
function (VF) driver (iavf).  Add support for flow types TCP4, TCP6,
UDP4, UDP6, SCTP4 and SCTP6 for RSS via ethtool.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Minor conflict in mlx5 because changes happened to code that has
moved meanwhile.
Signed-off-by: David S. Miller <davem@davemloft.net>

Bump version to 0.8.2-k
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Provide support to change or retrieve RSS hash options for a flow type.
The supported flow-types are: tcp4, tcp6, udp4, udp6, sctp4, sctp6.
Signed-off-by: Md Fahad Iqbal Polash <md.fahad.iqbal.polash@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Set configuration for hardware RSS tables for VFs.
Signed-off-by: Md Fahad Iqbal Polash <md.fahad.iqbal.polash@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Attempt to optimize TCAM entries and reduce table resource usage by
searching for profiles that can be reused. Provide resource cleanup
of both hardware and software structures.
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Henry Tieman <henry.w.tieman@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Write the hardware tables based on the populated software structures.
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Henry Tieman <henry.w.tieman@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Store the TCAM entry with the profile data and the VSI group in the
respective SW structures. This will be subsequently used to write out
the tables to hardware.
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Henry Tieman <henry.w.tieman@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Pull ARM fixes from Russell King:

 - fix ftrace relocation type filtering

 - relax arch timer version check

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 8955/1: virt: Relax arch timer version check during early boot
  ARM: 8950/1: ftrace/recordmcount: filter relocation types

Pull networking fixes from David Miller:

 1) Off by one in mt76 airtime calculation, from Dan Carpenter.

 2) Fix TLV fragment allocation loop condition in iwlwifi, from Luca
    Coelho.

 3) Don't confirm neigh entries when doing ipsec pmtu updates, from Xu
    Wang.

 4) More checks to make sure we only send TSO packets to lan78xx chips
    that they can actually handle. From James Hughes.

 5) Fix ip_tunnel namespace move, from William Dauchy.

 6) Fix unintended packet reordering due to cooperation between
    listification done by GRO and non-GRO paths. From Maxim
    Mikityanskiy.

 7) Add Jakub Kicincki formally as networking co-maintainer.

 8) Info leak in airo ioctls, from Michael Ellerman.

 9) IFLA_MTU attribute needs validation during rtnl_create_link(), from
    Eric Dumazet.

10) Use after free during reload in mlxsw, from Ido Schimmel.

11) Dangling pointers are possible in tp->highest_sack, fix from Eric
    Dumazet.

12) Missing *pos++ in various networking seq_next handlers, from Vasily
    Averin.

13) CHELSIO_GET_MEM operation neds CAP_NET_ADMIN check, from Michael
    Ellerman.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (109 commits)
  firestream: fix memory leaks
  net: cxgb3_main: Add CAP_NET_ADMIN check to CHELSIO_GET_MEM
  net: bcmgenet: Use netif_tx_napi_add() for TX NAPI
  tipc: change maintainer email address
  net: stmmac: platform: fix probe for ACPI devices
  net/mlx5e: kTLS, Do not send decrypted-marked SKBs via non-accel path
  net/mlx5e: kTLS, Remove redundant posts in TX resync flow
  net/mlx5e: kTLS, Fix corner-case checks in TX resync flow
  net/mlx5e: Clear VF config when switching modes
  net/mlx5: DR, use non preemptible call to get the current cpu number
  net/mlx5: E-Switch, Prevent ingress rate configuration of uplink rep
  net/mlx5: DR, Enable counter on non-fwd-dest objects
  net/mlx5: Update the list of the PCI supported devices
  net/mlx5: Fix lowest FDB pool size
  net: Fix skb->csum update in inet_proto_csum_replace16().
  netfilter: nf_tables: autoload modules from the abort path
  netfilter: nf_tables: add __nft_chain_type_get()
  netfilter: nf_tables_offload: fix check the chain offload flag
  netfilter: conntrack: sctp: use distinct states for new SCTP connections
  ipv6_route_seq_next should increase position index
  ...

Pull ARM SoC fixes from Olof Johansson:
 "A couple of fixes have come in that would be good to include in this
  release:

   - A fix for amount of memory on Beaglebone Black. Surfaced now since
     GRUB2 doesn't update memory size in the booted kernel.

   - A fix to make SPI interfaces work on am43x-epos-evm.

   - Small Kconfig fix for OPTEE (adds a depend on MMU) to avoid build
     failures"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  ARM: dts: am43x-epos-evm: set data pin directions for spi0 and spi1
  tee: optee: Fix compilation issue with nommu
  ARM: dts: am335x-boneblack-common: fix memory size

In fs_open(), 'vcc' is allocated through kmalloc() and assigned to
'atm_vcc->dev_data.' In the following execution, if an error occurs, e.g.,
there is no more free channel, an error code EBUSY or ENOMEM will be
returned. However, 'vcc' is not deallocated, leading to memory leaks. Note
that, in normal cases where fs_open() returns 0, 'vcc' will be deallocated
in fs_close(). But, if fs_open() fails, there is no guarantee that
fs_close() will be invoked.

To fix this issue, deallocate 'vcc' before the error code is returned.
Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Missing netlink attribute sanity check for NFTA_OSF_DREG,
   from Florian Westphal.

2) Use bitmap infrastructure in ipset to fix KASAN slab-out-of-bounds
   reads, from Jozsef Kadlecsik.

3) Missing initial CLOSED state in new sctp connection through
   ctnetlink events, from Jiri Wiesner.

4) Missing check for NFT_CHAIN_HW_OFFLOAD in nf_tables offload
   indirect block infrastructure, from wenxu.

5) Add __nft_chain_type_get() to sanity check family and chain type.

6) Autoload modules from the nf_tables abort path to fix races
   reported by syzbot.

7) Remove unnecessary skb->csum update on inet_proto_csum_replace16(),
   from Praveen Chaudhary.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull btrfs fix from David Sterba:
 "Here's a last minute fix for a regression introduced in this
  development cycle.

  There's a small chance of a silent corruption when device replace and
  NOCOW data writes happen at the same time in one block group. Metadata
  or COW data writes are unaffected.

  The extra fixup patch is there to silence an unnecessary warning"

* tag 'for-5.5-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: dev-replace: remove warning for unknown return codes when finished
  btrfs: scrub: Require mandatory block group RO for dev-replace

Pull pin control fix from Linus Walleij:
 "A single fix for the Intel Sunrisepoint pin controller that makes the
  interrupts work properly on it"

* tag 'pinctrl-v5.5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: sunrisepoint: Add missing Interrupt Status register offset

Saeed Mahameed says:

====================
Mellanox, mlx5 fixes 2020-01-24

This series introduces some fixes to mlx5 driver.

Please pull and let me know if there is any problem.

Merge conflict: once merge with net-next, a contextual conflict will
appear in drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
since the code moved in net-next.
To resolve, just delete ALL of the conflicting hunk from net.
So sorry for the small mess ..

For -stable v5.4:
 ('net/mlx5: Update the list of the PCI supported devices')
 ('net/mlx5: Fix lowest FDB pool size')
 ('net/mlx5e: kTLS, Fix corner-case checks in TX resync flow')
 ('net/mlx5e: kTLS, Do not send decrypted-marked SKBs via non-accel path')
 ('net/mlx5: Eswitch, Prevent ingress rate configuration of uplink rep')
 ('net/mlx5e: kTLS, Remove redundant posts in TX resync flow')
 ('net/mlx5: DR, Enable counter on non-fwd-dest objects')
 ('net/mlx5: DR, use non preemptible call to get the current cpu number')
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The fstests btrfs/011 triggered a warning at the end of device replace,

  [ 1891.998975] BTRFS warning (device vdd): failed setting block group ro: -28
  [ 1892.038338] BTRFS error (device vdd): btrfs_scrub_dev(/dev/vdd, 1, /dev/vdb) failed -28
  [ 1892.059993] ------------[ cut here ]------------
  [ 1892.063032] WARNING: CPU: 2 PID: 2244 at fs/btrfs/dev-replace.c:506 btrfs_dev_replace_start.cold+0xf9/0x140 [btrfs]
  [ 1892.074346] CPU: 2 PID: 2244 Comm: btrfs Not tainted 5.5.0-rc7-default+ #942
  [ 1892.079956] RIP: 0010:btrfs_dev_replace_start.cold+0xf9/0x140 [btrfs]

  [ 1892.096576] RSP: 0018:ffffbb58c7b3fd10 EFLAGS: 00010286
  [ 1892.098311] RAX: 00000000ffffffe4 RBX: 0000000000000001 RCX: 8888888888888889
  [ 1892.100342] RDX: 0000000000000001 RSI: ffff9e889645f5d8 RDI: ffffffff92821080
  [ 1892.102291] RBP: ffff9e889645c000 R08: 000001b8878fe1f6 R09: 0000000000000000
  [ 1892.104239] R10: ffffbb58c7b3fd08 R11: 0000000000000000 R12: ffff9e88a0017000
  [ 1892.106434] R13: ffff9e889645f608 R14: ffff9e88794e1000 R15: ffff9e88a07b5200
  [ 1892.108642] FS:  00007fcaed3f18c0(0000) GS:ffff9e88bda00000(0000) knlGS:0000000000000000
  [ 1892.111558] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [ 1892.113492] CR2: 00007f52509ff420 CR3: 00000000603dd002 CR4: 0000000000160ee0

  [ 1892.115814] Call Trace:
  [ 1892.116896]  btrfs_dev_replace_by_ioctl+0x35/0x60 [btrfs]
  [ 1892.118962]  btrfs_ioctl+0x1d62/0x2550 [btrfs]

caused by the previous patch ("btrfs: scrub: Require mandatory block
group RO for dev-replace"). Hitting ENOSPC is possible and could happen
when the block group is set read-only, preventing NOCOW writes to the
area that's being accessed by dev-replace.

This has happend with scratch devices of size 12G but not with 5G and
20G, so this is depends on timing and other activity on the filesystem.
The whole replace operation is restartable, the space state should be
examined by the user in any case.

The error code is propagated back to the ioctl caller so the kernel
warning is causing false alerts.
Signed-off-by: David Sterba <dsterba@suse.com>

Ido Schimmel says:

====================
mlxsw: Offload TBF

Petr says:

In order to allow configuration of shapers on Spectrum family of
machines, recognize TBF either as root Qdisc, or as a child of ETS or
PRIO. Configure rate of maximum shaper according to TBF rate setting,
and maximum shaper burst size according to TBF burst setting.

- Patches #1 and #2 make the TBF shaper suitable for offloading.
- Patches #3, #4 and #5 are refactoring aimed at easier support of leaf
  Qdiscs in general.
- Patches #6 to #10 gradually introduce TBF offload.
- Patches #11 to #14 add selftests.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Add a test that runs traffic across a port throttled with TBF. The test
checks that the observed throughput is within +-5% from the installed
shaper.

To allow checking both the software datapath and the offloaded one, make
the test suitable for inclusion from driver-specific wrapper. Introduce
such wrappers for mlxsw.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The function tc_rule_stats_get() fetches a packet counter of a given TC
rule. Extend it to support byte counters as well by adding an optional
argument with selector.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The function busywait() is handy as a safety-latched variant of a while
loop. Many selftests deal specifically with counter values, and busywaiting
on them is likely to be rather common (it is not quite common now, but
busywait() has not been around for very long). To facilitate expressing
simply what is tested, introduce two helpers:

- until_counter_is(), which can be used as a predicate passed to
  busywait(), which holds when expression, which is itself passed as an
  argument to until_counter_is(), reaches a desired value.

- busywait_for_counter(), which is useful for waiting until a given counter
  changes "by" (as opposed to "to") a certain amount.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The function humanize() is used for converting value in bits/s to a
human-friendly approximate value in Kbps, Mbps or Gbps. There is nothing
hardware-specific in that, so move the function to lib.sh.

Similarly for the rate() function, which just does a bit of math to
calculate a rate, given two counter values and a time interval.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

React to the TC messages that were introduced in a preceding patch and
configure egress maximum shaper as appropriate. TBF can be used as a root
qdisc or under one of PRIO or strict ETS bands.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In order to allow configuration of burst size together with shaper rate,
extend mlxsw_sp_port_ets_maxrate_set() with a burst_size argument. Convert
call sites to pass 0 (for default).
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Lower limit of burst size configuration is dependent on system type. Add a
datum to track the value. Initialize as appropriate in mlxsw_spX_init().
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As the port speeds grow, the current value of "unlimited shaper",
200000000Kbps, might become lower than the actually supported speeds. Bump
it to the maximum value that fits in the corresponding QEEC field, which is
about 2.1Tbps.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>