Add clock phandle, of the core clock driving the mdio block, as an
optional property to the Broadcom iProc mdio mux.

The clock, when specified, will be used to setup the rate adjust registers
in the mdio to derrive the mdio's operating frequency.
Signed-off-by: NArun Parameswaran <arun.parameswaran@broadcom.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use devm_mdiobus_alloc() instead of mdiobus_alloc() in the Broadcom
iProc mdio mux driver.
Signed-off-by: NArun Parameswaran <arun.parameswaran@broadcom.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Configure the scan control register in the Broadcom iProc
mdio mux driver to disable access to external master.

In some SoC's, the scan control register defaults to an incorrect
value.
Signed-off-by: NArun Parameswaran <arun.parameswaran@broadcom.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Modify the base address of the mdio mux driver to point to the
start of the mdio mux block's register address space.
Signed-off-by: NArun Parameswaran <arun.parameswaran@broadcom.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Modify the register offsets in the Broadcom iProc mdio mux to start
from the top of the register address space.

Earlier, the base address pointed to the end of the block's register
space. The base address will now point to the start of the mdio's
address space. The offsets have been fixed to match this.
Signed-off-by: NArun Parameswaran <arun.parameswaran@broadcom.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Modify the base address of the Broadcom iProc MDIO mux driver to
point to the start of the block's register address space.
Signed-off-by: NArun Parameswaran <arun.parameswaran@broadcom.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The BTF conflicts were simple overlapping changes.

The virtio_net conflict was an overlap of a fix of statistics counter,
happening alongisde a move over to a bonafide statistics structure
rather than counting value on the stack.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Trivial fix to spelling mistake in dev_info message.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NGanesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Check DMA addressing limitations as suggested by the DMA API
how-to. This does not fix a particular issue seen but is
considered good style.
Signed-off-by: NStefan Agner <stefan@agner.ch>
Acked-by: NFugang Duan <fugang.duan@nxp.com>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes gcc '-Wunused-but-set-variable' warning:

net/rxrpc/proc.c: In function 'rxrpc_call_seq_show':
net/rxrpc/proc.c:66:29: warning:
 variable 'nowj' set but not used [-Wunused-but-set-variable]
  unsigned long timeout = 0, nowj;
                             ^
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull networking fixes from David Miller:
 "Fixes keep trickling in:

  1) Various IP fragmentation memory limit hardening changes from Eric
     Dumazet.

  2) Revert ipv6 metrics leak change, it causes more problems than it
     fixes for now.

  3) Fix WoL regression in stmmac driver, from Jose Abreu.

  4) Netlink socket spectre v1 gadget fix, from Jeremy Cline"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  Revert "net/ipv6: fix metrics leak"
  rxrpc: Fix user call ID check in rxrpc_service_prealloc_one
  net: dsa: Do not suspend/resume closed slave_dev
  netlink: Fix spectre v1 gadget in netlink_create()
  Documentation: dpaa2: Use correct heading adornment
  net: stmmac: Fix WoL for PCI-based setups
  bonding: avoid lockdep confusion in bond_get_stats()
  enic: do not call enic_change_mtu in enic_probe
  ipv4: frags: handle possible skb truesize change
  inet: frag: enforce memory limits earlier
  net/mlx5e: IPoIB, Set the netdevice sw mtu in ipoib enhanced flow
  net/mlx5e: Fix null pointer access when setting MTU of vport representor
  net/mlx5e: Set port trust mode to PCP as default
  net/mlx5e: E-Switch, Initialize eswitch only if eswitch manager
  net: dsa: mv88e6xxx: Fix SERDES support on 88E6141/6341
  brcmfmac: fix regression in parsing NVRAM for multiple devices
  iwlwifi: add more card IDs for 9000 series

Previously in squashfs_readpage() when copying data into the page
cache, it used the length of the datablock read from the filesystem
(after decompression).  However, if the filesystem has been corrupted
this data block may be short, which will leave pages unfilled.

The fix for this is to compute the expected number of bytes to copy
from the inode size, and use this to detect if the block is short.
Signed-off-by: NPhillip Lougher <phillip@squashfs.org.uk>
Tested-by: NWilly Tarreau <w@1wt.eu>
Cc: Анатолий Тросиненко <anatoly.trosinenko@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The squashfs fragment reading code doesn't actually verify that the
fragment is inside the fragment table.  The end result _is_ verified to
be inside the image when actually reading the fragment data, but before
that is done, we may end up taking a page fault because the fragment
table itself might not even exist.

Another report from Anatoly and his endless squashfs image fuzzing.
Reported-by: NАнатолий Тросиненко <anatoly.trosinenko@gmail.com>
Acked-by:: Phillip Lougher <phillip.lougher@gmail.com>,
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit df18b504.

This change causes other problems and use-after-free situations as
found by syzbot.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull ARM fix from Russell King:
 "Just a single fix this time around for recent binutils causing build
  problems when generating Thumb-2 code"

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 8781/1: Fix Thumb-2 syscall return for binutils 2.29+

Fixes: 83ba4645 ("net: add helpers checking if socket can be bound to nonlocal address")
Signed-off-by: NVincent Bernat <vincent@bernat.im>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 2c4541e2 ("mm: use vma_init() to initialize VMAs on stack and
data segments") tried to initialize various left-over ad-hoc vma's
"properly", but actually made things worse for the temporary vma's used
for TLB flushing.

vma_init() doesn't actually initialize all of the vma, just a few
fields, so doing something like

   -       struct vm_area_struct vma = { .vm_mm = tlb->mm, };
   +       struct vm_area_struct vma;
   +
   +       vma_init(&vma, tlb->mm);

was actually very bad: instead of having a nicely initialized vma with
every field but "vm_mm" zeroed, you'd have an entirely uninitialized vma
with only a couple of fields initialized.  And they weren't even fields
that the code in question mostly cared about.

The flush_tlb_range() function takes a "struct vma" rather than a
"struct mm_struct", because a few architectures actually care about what
kind of range it is - being able to only do an ITLB flush if it's a
range that doesn't have data accesses enabled, for example.  And all the
normal users already have the vma for doing the range invalidation.

But a few people want to call flush_tlb_range() with a range they just
made up, so they also end up using a made-up vma.  x86 just has a
special "flush_tlb_mm_range()" function for this, but other
architectures (arm and ia64) do the "use fake vma" thing instead, and
thus got caught up in the vma_init() changes.

At the same time, the TLB flushing code really doesn't care about most
other fields in the vma, so vma_init() is just unnecessary and
pointless.

This fixes things by having an explicit "this is just an initializer for
the TLB flush" initializer macro, which is used by the arm/arm64/ia64
people who mis-use this interface with just a dummy vma.

Fixes: 2c4541e2 ("mm: use vma_init() to initialize VMAs on stack and data segments")
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Delete the old VM_BUG_ON_VMA() from zap_pmd_range(), which asserted
that mmap_sem must be held when splitting an "anonymous" vma there.
Whether that's still strictly true nowadays is not entirely clear,
but the danger of sometimes crashing on the BUG is now fairly clear.

Even with the new stricter rules for anonymous vma marking, the
condition it checks for can possible trigger. Commit 44960f2a
("staging: ashmem: Fix SIGBUS crash when traversing mmaped ashmem
pages") is good, and originally I thought it was safe from that
VM_BUG_ON_VMA(), because the /dev/ashmem fd exposed to the user is
disconnected from the vm_file in the vma, and madvise(,,MADV_REMOVE)
insists on VM_SHARED.

But after I read John's earlier mail, drawing attention to the
vfs_fallocate() in there: I may be wrong, and I don't know if Android
has THP in the config anyway, but it looks to me like an
unmap_mapping_range() from ashmem's vfs_fallocate() could hit precisely
the VM_BUG_ON_VMA(), once it's vma_is_anonymous().
Signed-off-by: NHugh Dickins <hughd@google.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

David Howells says:

====================
rxrpc: Development

Here are some patches that add some more tracepoints to AF_RXRPC and fix
some issues therein.  The most significant points are:

 (1) Display the call timeout information in /proc/net/rxrpc/calls.

 (2) Save the call's debug_id in the rxrpc_channel struct so that it can be
     used in traces after the rxrpc_call struct has been destroyed.

 (3) Increase the size of the kAFS Rx window from 32 to 63 to be about the
     same as the Auristor server.

 (4) Propose the terminal ACK for a client call after it has received all
     its data to be transmitted after a short interval so that it will get
     transmitted if not first superseded by a new call on the same channel.

 (5) Flush ACKs during the data reception if we detect that we've run out
     of data.[*]

 (6) Trace successful packet transmission and softirq to process context
     socket notification.

[*] Note that on a uncontended gigabit network, rxrpc runs in to trouble
    with ACK packets getting batched together (up to ~32 at a time)
    somewhere between the IP transmit queue on the client and the ethernet
    receive queue on the server.

    I can see the kernel afs filesystem client and Auristor userspace
    server stalling occasionally on a 512MB single read.  Sticking
    tracepoints in the network driver at either end seems to show that,
    although the ACK transmissions made by the client are reasonably spaced
    timewise, the received ACKs come in batches from the network card on
    the server.

    I'm not sure what, if anything, can be done about this.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There just check the user call ID isn't already in use, hence should
compare user_call_ID with xcall->user_call_ID, which is current
node's user_call_ID.

Fixes: 540b1c48 ("rxrpc: Fix deadlock between call creation and sendmsg/recvmsg")
Suggested-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull MMC fix from Ulf Hansson:
 "MMC host: mxcmmc: Fix build error for powerpc"

* tag 'mmc-v4.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: mxcmmc: Fix missing parentheses and brace

Pull power management fixes from Rafael Wysocki:
 "These fix the scope of a recent intel_pstate driver optimization used
  incorrectly on some systems due to processor identification ambiguity
  and fix a few issues in the turbostat utility, including three recent
  regressions.

  Specifics:

   - Use ACPI FADT preferred PM Profile to distinguish Skylake desktop
     processors from some server ones with the same model number in
     order to limit the scope of the recent IO-wait boost optimization
     to servers, as intended (Srinivas Pandruvada).

   - Fix several issues in the turbostat utility:
      * Fix the -S option on 1-CPU systems (Len Brown).
      * Fix computations using incorrect processor core counts (Artem
        Bityutskiy).
      * Fix the x2apic debug message (Len Brown).
      * Fix logical node enumeration to allow for non-sequential
        physical nodes (Prarit Bhargava).
      * Fix reported family on modern AMD processors (Calvin Walton).
      * Clarify the RAPL column information in the man page (Len Brown)"

* tag 'pm-urgent-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: intel_pstate: Limit the scope of HWP dynamic boost platforms
  tools/power turbostat: version 18.07.27
  tools/power turbostat: Read extended processor family from CPUID
  tools/power turbostat: Fix logical node enumeration to allow for non-sequential physical nodes
  tools/power turbostat: fix x2apic debug message output file
  tools/power turbostat: fix bogus summary values
  tools/power turbostat: fix -S on UP systems
  tools/power turbostat: Update turbostat(8) RAPL throttling column description

Anatoly continues to find issues with fuzzed squashfs images.

This time, corrupt, missing, or undersized data for the page filling
wasn't checked for, because the squashfs_{copy,read}_cache() functions
did the squashfs_copy_data() call without checking the resulting data
size.

Which could result in the page cache pages being incompletely filled in,
and no error indication to the user space reading garbage data.

So make a helper function for the "fill in pages" case, because the
exact same incomplete sequence existed in two places.

[ I should have made a squashfs branch for these things, but I didn't
  intend to start doing them in the first place.

  My historical connection through cramfs is why I got into looking at
  these issues at all, and every time I (continue to) think it's a
  one-off.

  Because _this_ time is always the last time. Right?   - Linus ]
Reported-by: NAnatoly Trosinenko <anatoly.trosinenko@gmail.com>
Tested-by: NWilly Tarreau <w@1wt.eu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Amit Pundir and Youling in parallel reported crashes with recent
mainline kernels running Android:

  F DEBUG   : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
  F DEBUG   : Build fingerprint: 'Android/db410c32_only/db410c32_only:Q/OC-MR1/102:userdebug/test-key
  F DEBUG   : Revision: '0'
  F DEBUG   : ABI: 'arm'
  F DEBUG   : pid: 2261, tid: 2261, name: zygote  >>> zygote <<<
  F DEBUG   : signal 7 (SIGBUS), code 2 (BUS_ADRERR), fault addr 0xec00008
  ... <snip> ...
  F DEBUG   : backtrace:
  F DEBUG   :     #00 pc 00001c04  /system/lib/libc.so (memset+48)
  F DEBUG   :     #1 pc 0010c513  /system/lib/libart.so (create_mspace_with_base+82)
  F DEBUG   :     #2 pc 0015c601  /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateMspace(void*, unsigned int, unsigned int)+40)
  F DEBUG   :     #3 pc 0015c3ed  /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateFromMemMap(art::MemMap*, std::__1::basic_string<char, std::__ 1::char_traits<char>, std::__1::allocator<char>> const&, unsigned int, unsigned int, unsigned int, unsigned int, bool)+36)
  ...

This was bisected back to commit bfd40eaf ("mm: fix
vma_is_anonymous() false-positives").

create_mspace_with_base() in the trace above, utilizes ashmem, and with
ashmem, for shared mappings we use shmem_zero_setup(), which sets the
vma->vm_ops to &shmem_vm_ops.  But for private ashmem mappings nothing
sets the vma->vm_ops.

Looking at the problematic patch, it seems to add a requirement that one
call vma_set_anonymous() on a vma, otherwise the dummy_vm_ops will be
used.  Using the dummy_vm_ops seem to triggger SIGBUS when traversing
unmapped pages.

Thus, this patch adds a call to vma_set_anonymous() for ashmem private
mappings and seems to avoid the reported problem.

Fixes: bfd40eaf ("mm: fix vma_is_anonymous() false-positives")
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Colin Cross <ccross@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Reported-by: NAmit Pundir <amit.pundir@linaro.org>
Reported-by: NYouling 257 <youling257@gmail.com>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For FW_PORT_ACTION_GET_PORT_INFO32 messages, the
u.info32.lstatus32_to_cbllen32 is 32-bit Big Endian.
We need to translate that to CPU Endian in order to
test F_FW_PORT_CMD_DCBXDIS32.
Signed-off-by: NCasey Leedom <leedom@chelsio.com>
Signed-off-by: NGanesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Jiri Pirko says:

====================
net: sched: couple of adjustments/fixes
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These are no longer used outside of cls_api.c so make them static.
Move tcf_chain_flush() to avoid fwd declaration of tcf_chain_put().
Signed-off-by: NJiri Pirko <jiri@mellanox.com>

v1->v2:
- new patch
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Chains that only have action references serve as placeholders.
Until a non-action reference is created, user should not be aware
of the chain. Also he should not receive any notifications about it.
So send notifications for the new chain only in case the chain gets
the first non-action reference. Symmetrically to that, when
the last non-action reference is dropped, send the notification about
deleted chain.
Reported-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>

v1->v2:
- made __tcf_chain_{get,put}() static as suggested by Cong
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As mentioned by Cong and Jakub during the review process, it is a bit
odd to sometimes (act flow) create a new chain which would be
immediately a "zombie". So just rename it to "held_by_acts_only".
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Suggested-by: NCong Wang <xiyou.wangcong@gmail.com>
Suggested-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While cleaning the command queue, the value of the HEAD register is not
in the range of next_to_clean and next_to_use, meaning that this value
is invalid. This also means that there is a hardware error and the
hardware will trigger a reset soon. At this time we should return an
error code instead of 0, and HCLGE_STATE_CMD_DISABLE needs to be set to
prevent sending command again.

Fixes: 3ff50490 ("net: hns3: fix a dead loop in hclge_cmd_csq_clean")
Signed-off-by: NHuazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: NSalil Mehta <salil.mehta@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Variable 'rds_ibdev' is being assigned but never used,
so can be removed.

fix this clang warning:
 net/rds/ib_send.c:762:24: warning: variable ‘rds_ibdev’ set but not used [-Wunused-but-set-variable]
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Variable 'rd_desc' is being assigned but never used,
so can be removed.

fix this clang warning:
net/strparser/strparser.c:411:20: warning: variable ‘rd_desc’ set but not used [-Wunused-but-set-variable]
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After commit ffc2b6ee ("ip_gre: fix IFLA_MTU ignored on NEWLINK")
variable t_hlen is assigned values that are never read,
hence they are redundant and can be removed.
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit bfd40eaf ("mm: fix vma_is_anonymous() false-positives") made
newly allocated vma's have a dummy vm_ops field so that they wouldn't be
mistaken for anonymous mappings, and if you wanted an anonymous vma you
had to explicitly say so by calling "vma_set_anonymous()" on it.

However, it missed the two special vmas that ia64 processes have: the
register backing store and the NaT page.  So they wouldn't actually act
like anonymous ranges, and page faults on them caused a SIGBUS rather
than the creation of a new anon page in them.

That obviously will make any ia64 binary very unhappy indeed, and the
boot fails early.

Fixes: bfd40eaf ("mm: fix vma_is_anonymous() false-positives")
Reported-by: NTony Luck <tony.luck@intel.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixes gcc '-Wunused-but-set-variable' warning:

net/ipv4/tcp_output.c: In function 'tcp_collapse_retrans':
net/ipv4/tcp_output.c:2700:6: warning:
 variable 'skb_size' set but not used [-Wunused-but-set-variable]
  int skb_size, next_skb_size;
      ^
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Wei Wang says:

====================
tcp: add 4 new stats

This patch series adds 3 RFC4898 stats:
1. tcpEStatsPerfHCDataOctetsOut
2. tcpEStatsPerfOctetsRetrans
3. tcpEStatsStackDSACKDups
and an addtional stat to record the number of data packet reordering
events seen:
4. tcp_reord_seen

Together with the existing stats, application can use them to measure
the retransmission rate in bytes, exclude spurious retransmissions
reflected by DSACK, and keep track of the reordering events on live
connections.
In particular the networks with different MTUs make bytes-based loss stats
more useful. Google servers have been using these stats for many years to
instrument transport and network performance.

Note: The first patch is a refactor to add a helper to calculate
opt_stats size in order to make later changes cleaner.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce a new TCP stats to record the number of reordering events seen
and expose it in both tcp_info (TCP_INFO) and opt_stats
(SOF_TIMESTAMPING_OPT_STATS).
Application can use this stats to track the frequency of the reordering
events in addition to the existing reordering stats which tracks the
magnitude of the latest reordering event.

Note: this new stats tracks reordering events triggered by ACKs, which
could often be fewer than the actual number of packets being delivered
out-of-order.
Signed-off-by: NWei Wang <weiwan@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce a new TCP stat to record the number of DSACK blocks received
(RFC4989 tcpEStatsStackDSACKDups) and expose it in both tcp_info
(TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS).
Signed-off-by: NWei Wang <weiwan@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce a new TCP stat to record the number of bytes retransmitted
(RFC4898 tcpEStatsPerfOctetsRetrans) and expose it in both tcp_info
(TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS).
Signed-off-by: NWei Wang <weiwan@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>