Add a very rudimentary active buffer management NIC support.
For now it's like a core NIC without SR-IOV support.  Next
commits will extend its functionality.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Current code doesn't enforce length requirements on 32bit accesses
with action NFP_CPP_ACTION_RW to memory units, but if the access
is only aligned to 4 bytes as well we will fall into the explicit
access case and error out.  Such accesses are correct, allow them
by lowering the width earlier.

While at it use a switch statement to improve readability.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Allow app FW to advertise its shared buffer pool information.
Use the per-PF mailbox to configure them from devlink.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When working with devlink-related functionality for locking reasons
it's easier to create a new mailbox per-PCI PF device than try to
use one of the netdev/vNIC mailboxes.

Define new mailbox structure and resolve its symbol during probe.
For forward compatibility allow silent truncation of mailbox command
data.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

nfp_net_pf_rtsym_read_optional() and nfp_net_pf_map_rtsym() are not
really related to networking code.  Move them to the PF code and
remove the net from their names.  They will soon be needed by code
outside of nfp_net_main.c anyway.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Alexei Starovoitov says:

====================
bpfilter

v2->v3:
- followed Luis's suggestion and significantly simplied first patch
  with shmem_kernel_file_setup+kernel_write. Added kdoc for new helper
- fixed typos and race to access pipes with mutex
- tested with bpfilter being 'builtin'. CONFIG_BPFILTER_UMH=y|m both work.
  Interesting to see a usermode executable being embedded inside vmlinux.
- it doesn't hurt to enable bpfilter in .config.
  ip_setsockopt commands sent to usermode via pipes and -ENOPROTOOPT is
  returned from userspace, so kernel falls back to original iptables code

v1->v2:
this patch set is almost a full rewrite of the earlier umh modules approach
The v1 of patches and follow up discussion was covered by LWN:
https://lwn.net/Articles/749108/

I believe the v2 addresses all issues brought up by Andy and others.
Mainly there are zero changes to kernel/module.c
Instead of teaching module loading logic to recognize special
umh module, let normal kernel modules execute part of its own
.init.rodata as a new user space process (Andy's idea)
Patch 1 introduces this new helper:
int fork_usermode_blob(void *data, size_t len, struct umh_info *info);
Input:
  data + len == executable file
Output:
  struct umh_info {
       struct file *pipe_to_umh;
       struct file *pipe_from_umh;
       pid_t pid;
  };

Advantages vs v1:
- the embedded user mode executable is stored as .init.rodata inside
  normal kernel module. These pages are freed when .ko finishes loading
- the elf file is copied into tmpfs file. The user mode process is swappable.
- the communication between user mode process and 'parent' kernel module
  is done via two unix pipes, hence protocol is not exposed to
  user space
- impossible to launch umh on its own (that was the main issue of v1)
  and impossible to be man-in-the-middle due to pipes
- bpfilter.ko consists of tiny kernel part that passes the data
  between kernel and umh via pipes and much bigger umh part that
  doing all the work
- 'lsmod' shows bpfilter.ko as usual.
  'rmmod bpfilter' removes kernel module and kills corresponding umh
- signed bpfilter.ko covers the whole image including umh code

Few issues:
- the user can still attach to the process and debug it with
  'gdb /proc/pid/exe pid', but 'gdb -p pid' doesn't work.
  (a bit worse comparing to v1)
- tinyconfig will notice a small increase in .text
  +766 | TEXT | 7c8b94806bec umh: introduce fork_usermode_blob() helper
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

bpfilter.ko consists of bpfilter_kern.c (normal kernel module code)
and user mode helper code that is embedded into bpfilter.ko

The steps to build bpfilter.ko are the following:
- main.c is compiled by HOSTCC into the bpfilter_umh elf executable file
- with quite a bit of objcopy and Makefile magic the bpfilter_umh elf file
  is converted into bpfilter_umh.o object file
  with _binary_net_bpfilter_bpfilter_umh_start and _end symbols
  Example:
  $ nm ./bld_x64/net/bpfilter/bpfilter_umh.o
  0000000000004cf8 T _binary_net_bpfilter_bpfilter_umh_end
  0000000000004cf8 A _binary_net_bpfilter_bpfilter_umh_size
  0000000000000000 T _binary_net_bpfilter_bpfilter_umh_start
- bpfilter_umh.o and bpfilter_kern.o are linked together into bpfilter.ko

bpfilter_kern.c is a normal kernel module code that calls
the fork_usermode_blob() helper to execute part of its own data
as a user mode process.

Notice that _binary_net_bpfilter_bpfilter_umh_start - end
is placed into .init.rodata section, so it's freed as soon as __init
function of bpfilter.ko is finished.
As part of __init the bpfilter.ko does first request/reply action
via two unix pipe provided by fork_usermode_blob() helper to
make sure that umh is healthy. If not it will kill it via pid.

Later bpfilter_process_sockopt() will be called from bpfilter hooks
in get/setsockopt() to pass iptable commands into umh via bpfilter.ko

If admin does 'rmmod bpfilter' the __exit code bpfilter.ko will
kill umh as well.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Introduce helper:
int fork_usermode_blob(void *data, size_t len, struct umh_info *info);
struct umh_info {
       struct file *pipe_to_umh;
       struct file *pipe_from_umh;
       pid_t pid;
};

that GPLed kernel modules (signed or unsigned) can use it to execute part
of its own data as swappable user mode process.

The kernel will do:
- allocate a unique file in tmpfs
- populate that file with [data, data + len] bytes
- user-mode-helper code will do_execve that file and, before the process
  starts, the kernel will create two unix pipes for bidirectional
  communication between kernel module and umh
- close tmpfs file, effectively deleting it
- the fork_usermode_blob will return zero on success and populate
  'struct umh_info' with two unix pipes and the pid of the user process

As the first step in the development of the bpfilter project
the fork_usermode_blob() helper is introduced to allow user mode code
to be invoked from a kernel module. The idea is that user mode code plus
normal kernel module code are built as part of the kernel build
and installed as traditional kernel module into distro specified location,
such that from a distribution point of view, there is
no difference between regular kernel modules and kernel modules + umh code.
Such modules can be signed, modprobed, rmmod, etc. The use of this new helper
by a kernel module doesn't make it any special from kernel and user space
tooling point of view.

Such approach enables kernel to delegate functionality traditionally done
by the kernel modules into the user space processes (either root or !root) and
reduces security attack surface of the new code. The buggy umh code would crash
the user process, but not the kernel. Another advantage is that umh code
of the kernel module can be debugged and tested out of user space
(e.g. opening the possibility to run clang sanitizers, fuzzers or
user space test suites on the umh code).
In case of the bpfilter project such architecture allows complex control plane
to be done in the user space while bpf based data plane stays in the kernel.

Since umh can crash, can be oom-ed by the kernel, killed by the admin,
the kernel module that uses them (like bpfilter) needs to manage life
time of umh on its own via two unix pipes and the pid of umh.

The exit code of such kernel module should kill the umh it started,
so that rmmod of the kernel module will cleanup the corresponding umh.
Just like if the kernel module does kmalloc() it should kfree() it
in the exit code.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sudarsana Reddy Kalluru says:

====================
qed*: Add support for management firmware TLV request.

Management firmware (MFW) requires config and state information from
the driver. It queries this via TLV (type-length-value) request wherein
mfw specificies the list of required TLVs. Driver fills the TLV data
and responds back to MFW.
This patch series adds qed/qede/qedf/qedi driver implementation for
supporting the TLV queries from MFW.

Changes from previous versions:
-------------------------------
v2: Split patch (2) into multiple simpler patches.
v2: Update qed_tlv_parsed_buf->p_val datatype to void pointer to avoid
    bunch of unnecessary typecasts.

Please consider applying this series to "net-next".
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Manish Rangankar <manish.rangankar@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds callbacks for providing the ethernet protocol driver TLVs.
Signed-off-by: Manish Rangankar <manish.rangankar@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Chad Dupuis <chad.dupuis@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds callbacks for providing the ethernet protocol driver TLVs.
Signed-off-by: Chad Dupuis <chad.dupuis@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds callbacks for providing the ethernet protocol driver TLVs.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

MFW requests the TLVs in interrupt context. Extracting of the required
data from upper layers and populating of the TLVs require process context.
The patch adds work-queues for processing the tlv requests. It also adds
the implementation for requesting the tlv values from appropriate protocol
driver.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The patch adds driver support for processing TLV requests/repsonses
from the mfw and upper driver layers respectively. The implementation
reads the requested TLVs from the shared memory, requests the values
from upper layer drivers, populates this info (TLVs) shared memory and
notifies MFW about the TLV values.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The patch adds required management firmware (MFW) interfaces such as
mailbox commands, TLV types etc.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
40GbE Intel Wired LAN Driver Updates 2018-05-22

This series contains updates to i40e only.

Jake provides all the changes in this series starting with making it
consistent in how we approach the bit lock.  Fixed the reporting of the
VEB statistics and the queue statistics to always return every queue
even if it is not currently in use.  Use WARN_ONCE() so that the first
time we end up with an incorrect size we will dump a stack trace and a
message to help highlight the issue early in testing.  Folded the fixed
string prefix into the stat string definition.  Instead of using a
separate char *p pointer when copying strings, use the data pointer
directly.  Added code comments for several of the statistic functions to
better explain the number and ordering of statistics.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
tcp: reduce quickack pressure for ECN

Small patch series changing TCP behavior vs quickack and ECN

First patch is a refactoring, adding parameter to tcp_incr_quickack()
and tcp_enter_quickack_mode() helpers.

Second patch implements the change, lowering number of ACK packets
sent after an ECN event.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

ECN signals currently forces TCP to enter quickack mode for
up to 16 (TCP_MAX_QUICKACKS) following incoming packets.

We believe this is not needed, and only sending one immediate ack
for the current packet should be enough.

This should reduce the extra load noticed in DCTCP environments,
after congestion events.

This is part 2 of our effort to reduce pure ACK packets.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We want to add finer control of the number of ACK packets sent after
ECN events.

This patch is not changing current behavior, it only enables following
change.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Initial net_device implementation used ingress_lock spinlock to synchronize
ingress path of device. This lock was used in both process and bh context.
In some code paths action map lock was obtained while holding ingress_lock.
Commit e1e992e5 ("[NET_SCHED] protect action config/dump from irqs")
modified actions to always disable bh, while using action map lock, in
order to prevent deadlock on ingress_lock in softirq. This lock was removed
from net_device, so disabling bh, while accessing action map, is no longer
necessary.

Replace all action idr spinlock usage with regular calls that do not
disable bh.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

David Ahern says:

====================
net/ipv6: Fix route append and replace use cases

This patch set fixes a few append and replace uses cases for IPv6 and
adds test cases that codifies the expectations of how append and replace
are expected to work. In paricular it allows a multipath route to have
a dev-only nexthop, something Thomas tried to accomplish with commit
edd7ceb7 ("ipv6: Allow non-gateway ECMP for IPv6") which had to be
reverted because of breakage, and to replace an existing FIB entry
with a reject route.

There are a number of inconsistent and surprising aspects to the Linux
API for adding, deleting, replacing and changing FIB entries. For example,
with IPv4 NLM_F_APPEND means insert the route after any existing entries
with the same key (prefix + priority + TOS for IPv4) and NLM_F_CREATE
without the append flag inserts the new route before any existing entries.

IPv6 on the other hand attempts to guess whether a new route should be
appended to an existing one, possibly creating a multipath route, or to
add a new entry after any existing ones. This applies to both the 'append'
(NLM_F_CREATE + NLM_F_APPEND) and 'prepend' (NLM_F_CREATE only) cases
meaning for IPv6 the NLM_F_APPEND is basically ignored. This guessing
whether the route should be added to a multipath route (gateway routes)
or inserted after existing entries (non-gateway based routes) means a
multipath route can not have a dev only nexthop (potentially required in
some cases - tunnels or VRF route leaking for example) and route 'replace'
is a bit adhoc treating gateway based routes and dev-only / reject routes
differently.

This has led to frustration with developers working on routing suites
such as FRR where workarounds such as delete and add are used instead of
replace.

After this patch set there are 2 differences between IPv4 and IPv6:
1. 'ip ro prepend' = NLM_F_CREATE only
    IPv4 adds the new route before any existing ones
    IPv6 adds new route after any existing ones

2. 'ip ro append' = NLM_F_CREATE|NLM_F_APPEND
   IPv4 adds the new route after any existing ones
   IPv6 adds the nexthop to existing routes converting to multipath

For the former, there are cases where we want same prefix routes added
after existing ones (e.g., multicast, prefix routes for macvlan when used
for virtual router redundancy). Requiring the APPEND flag to add a new
route to an existing one helps here but is a slight change in behavior
since prepend with gateway routes now create a separate entry.

For the latter IPv6 behavior is preferred - appending a route for the same
prefix and metric to make a multipath route, so really IPv4 not allowing an
existing route to be updated is the limiter. This will be fixed when
nexthops become separate objects - a future patch set.

Thank you to Thomas and Ido for testing earlier versions of this set, and
to Ido for providing an update to the mlxsw driver.

Changes since RFC
- cleanup wording in test script; add comments about expected failures
  and why
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Add IPv4 route tests covering add, append and replace permutations.
Assumes the ability to add a basic single path route works; this is
required for example when adding an address to an interface.

$ fib_tests.sh -t ipv4_rt

IPv4 route add / append tests
    TEST: Attempt to add duplicate route - gw                           [ OK ]
    TEST: Attempt to add duplicate route - dev only                     [ OK ]
    TEST: Attempt to add duplicate route - reject route                 [ OK ]
    TEST: Add new nexthop for existing prefix                           [ OK ]
    TEST: Append nexthop to existing route - gw                         [ OK ]
    TEST: Append nexthop to existing route - dev only                   [ OK ]
    TEST: Append nexthop to existing route - reject route               [ OK ]
    TEST: Append nexthop to existing reject route - gw                  [ OK ]
    TEST: Append nexthop to existing reject route - dev only            [ OK ]
    TEST: add multipath route                                           [ OK ]
    TEST: Attempt to add duplicate multipath route                      [ OK ]
    TEST: Route add with different metrics                              [ OK ]
    TEST: Route delete with metric                                      [ OK ]

IPv4 route replace tests
    TEST: Single path with single path                                  [ OK ]
    TEST: Single path with multipath                                    [ OK ]
    TEST: Single path with reject route                                 [ OK ]
    TEST: Single path with single path via multipath attribute          [ OK ]
    TEST: Invalid nexthop                                               [ OK ]
    TEST: Single path - replace of non-existent route                   [ OK ]
    TEST: Multipath with multipath                                      [ OK ]
    TEST: Multipath with single path                                    [ OK ]
    TEST: Multipath with single path via multipath attribute            [ OK ]
    TEST: Multipath with reject route                                   [ OK ]
    TEST: Multipath - invalid first nexthop                             [ OK ]
    TEST: Multipath - invalid second nexthop                            [ OK ]
    TEST: Multipath - replace of non-existent route                     [ OK ]
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add IPv6 route tests covering add, append and replace permutations.
Assumes the ability to add a basic single path route works; this is
required for example when adding an address to an interface.

$ fib_tests.sh -t ipv6_rt

IPv6 route add / append tests
    TEST: Attempt to add duplicate route - gw                           [ OK ]
    TEST: Attempt to add duplicate route - dev only                     [ OK ]
    TEST: Attempt to add duplicate route - reject route                 [ OK ]
    TEST: Add new route for existing prefix (w/o NLM_F_EXCL)            [ OK ]
    TEST: Append nexthop to existing route - gw                         [ OK ]
    TEST: Append nexthop to existing route - dev only                   [ OK ]
    TEST: Append nexthop to existing route - reject route               [ OK ]
    TEST: Append nexthop to existing reject route - gw                  [ OK ]
    TEST: Append nexthop to existing reject route - dev only            [ OK ]
    TEST: Add multipath route                                           [ OK ]
    TEST: Attempt to add duplicate multipath route                      [ OK ]
    TEST: Route add with different metrics                              [ OK ]
    TEST: Route delete with metric                                      [ OK ]

IPv6 route replace tests
    TEST: Single path with single path                                  [ OK ]
    TEST: Single path with multipath                                    [ OK ]
    TEST: Single path with reject route                                 [ OK ]
    TEST: Single path with single path via multipath attribute          [ OK ]
    TEST: Invalid nexthop                                               [ OK ]
    TEST: Single path - replace of non-existent route                   [ OK ]
    TEST: Multipath with multipath                                      [ OK ]
    TEST: Multipath with single path                                    [ OK ]
    TEST: Multipath with single path via multipath attribute            [ OK ]
    TEST: Multipath with reject route                                   [ OK ]
    TEST: Multipath - invalid first nexthop                             [ OK ]
    TEST: Multipath - invalid second nexthop                            [ OK ]
    TEST: Multipath - replace of non-existent route                     [ OK ]
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add option to pause after each test before cleanup is done. Allows
user to do manual inspection or more ad-hoc testing after each test
with the setup in tact.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add command line options for controlling pause on fail, controlling
specific tests to run and verbose mode rather than relying on environment
variables.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As more tests are added, it is convenient to have a tally at the end.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Bring consistency to ipv6 route replace and append semantics.

Remove rt6_qualify_for_ecmp which is just guess work. It fails in 2 cases:
1. can not replace a route with a reject route. Existing code appends
   a new route instead of replacing the existing one.

2. can not have a multipath route where a leg uses a dev only nexthop

Existing use cases affected by this change:
1. adding a route with existing prefix and metric using NLM_F_CREATE
   without NLM_F_APPEND or NLM_F_EXCL (ie., what iproute2 calls
   'prepend'). Existing code auto-determines that the new nexthop can
   be appended to an existing route to create a multipath route. This
   change breaks that by requiring the APPEND flag for the new route
   to be added to an existing one. Instead the prepend just adds another
   route entry.

2. route replace. Existing code replaces first matching multipath route
   if new route is multipath capable and fallback to first matching
   non-ECMP route (reject or dev only route) in case one isn't available.
   New behavior replaces first matching route. (Thanks to Ido for spotting
   this one)

Note: Newer iproute2 is needed to display multipath routes with a dev-only
      nexthop. This is due to a bug in iproute2 and parsing nexthops.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Handle append for gateway based routes. Dev-only multipath routes will
be handled by a follow on patch.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since we no longer use i as an array index for the data variable,
replace the use of 'j' with 'i' so that we match the general loop
variable name.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Add documentation for the i40e_get_stats_count, i40e_get_stat_strings
and i40e_get_ethtool_stats explaining that the number and ordering of
statistics must remain constant for a given netdevice.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

A future patch is going to add a helper function i40e_add_ethtool_stats
that will help lower the amount of boiler plate code in the
i40e_get_ethtool_stats function.

This conversion will take place over many patches, and the helper
function will work by directly updating a reference to the data pointer.

Since this would not work combined with the current method of accessing
data like an array, update all the code that copies stats into the data
buffer to use direct updates to the pointer instead of array accesses.

This will prevent incorrect stat updates for patches in between the
conversion.

Similarly, when copying strings, we used a separate char *p pointer.
Instead, use the data pointer directly as it's already a (u8 *) type
which is the same size.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

We always prefix these stats with a fixed string, so just fold this
prefix into the stat string definition. This preparatory work will make
it easier to implement a helper function to copy stats and strings into
the supplied buffers in a future patch.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

We don't really want to use BUG_ON here since that would completely
crash the kernel, thus the reason we commented it out. We *can't* use
BUILD_BUG_ON because at least now (a) the sizes aren't constant (we are
fixing this) and (b) not all compilers are smart enough to understand
that "p - data" is a constant.

Instead, just use a WARN_ONCE so that the first time we end up with an
incorrect size we will dump a stack trace and a message, hopefully
highlighting the issues early in testing.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Split the statistic strings and private flags strings into their own
separate functions to aid code readability.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

The ethtool API for obtaining device statistics is not intended to allow
runtime changes in the number of statistics reported. It may *appear*
this way, as there is an ability to request the number of stats using
ethtool_get_set_count(). However, it is expected that this must always
return the same value for invocations of the same device.

If we don't satisfy this contract, and allow the number of stats to
change during run time, we could cause invalid memory accesses or report
the stat strings incorrectly. This is because the API for obtaining
stats is to (1) get the size, (2) get the strings and finally (3) get
the stats. Since these are each separate ethtool op commands, it is not
possible to maintain consistency by holding the RTNL lock over the whole
operation. This results in the potential for a race condition to occur
where the size changed between any of the 3 calls.

Avoid this issue by requiring that we always return the same value for
a given device. We can check any values which remain constant for the
life of the device, but must not report different sizes depending on
runtime attributes.

This patch specifically fixes the queue statistics to always return
every queue even if it's not currently in use.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

The ethtool API for obtaining device statistics is not intended to allow
runtime changes in the number of statistics reported. It may *appear*
this way, as there is an ability to request the number of stats using
ethtool_get_set_count(). However, it is expected that this must always
return the same value for invocations of the same device.

If we don't satisfy this contract, and allow the number of stats to
change during run time, we could cause invalid memory accesses or report
the stat strings incorrectly. This is because the API for obtaining
stats is to (1) get the size, (2) get the strings and finally (3) get
the stats. Since these are each separate ethtool op commands, it is not
possible to maintain consistency by holding the RTNL lock over the whole
operation. This results in the potential for a race condition to occur
where the size changed between any of the 3 calls.

Avoid this issue by requiring that we always return the same value for
a given device. We can check any values which remain constant for the
life of the device, but must not report different sizes depending on
runtime attributes.

This patch specifically fixes the VEB statistics strings to always be
reported. Other issues will be fixed in future patches.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>