The callbacks have been slimmed down to a level where they no longer do
any actual work. So stop pretending that we support the
NETIF_F_HW_VLAN_CTAG_FILTER feature.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As part of the TX queue selection for af_iucv skbs,
qeth_l3_get_cast_type_rcu() ends up calling qeth_get_ether_cast_type().
Which is rather fragile, since such skbs don't have a proper ETH header
and we rely on it being zeroed out in the right places. Add a separate
case for ETH_P_AF_IUCV instead that does the right thing.

When later building the HW header for such skbs, don't hard-code the
cast type but follow the same path as for other protocol types. Here
the cast type should naturally come from the skb's queue mapping.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

qeth_l3_hard_start_xmit() already determined the skb's proto. Avoid
doing so a second time when it calls qeth_l3_get_cast_type().
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

Replace our home-grown helper with the more robust vlan_get_protocol().
This is pretty much a 1:1 replacement, we just need to pass around a
proper ETH_P_* everyhwere and convert the old value range.

For readability also convert the protocol checks in
qeth_l3_hard_start_xmit() to a switch statement.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

ip_finish_output_gso() may call .ndo_features_check() even before the
skb has a L2 header. This conflicts with qeth_get_ip_version()'s attempt
to inspect the L2 header via vlan_eth_hdr().

Switch to vlan_get_protocol(), as already used further down in the
common qeth_features_check() path.

Fixes: f13ade19 ("s390/qeth: run non-offload L3 traffic over common xmit path")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

Due to insufficient locking, qeth_core_set_online() and
qeth_dev_layer2_store() can run in parallel, both attempting to load &
setup the discipline (and stepping on each other toes along the way).
A similar race can also occur between qeth_core_remove_device() and
qeth_dev_layer2_store().

Access to .discipline is meant to be protected by the discipline_mutex,
so add/expand the locking in qeth_core_remove_device() and
qeth_core_set_online().
Adjust the locking in qeth_l*_remove_device() accordingly, as it's now
handled by the callers in a consistent manner.

Based on an initial patch by Ursula Braun.

Fixes: 9dc48ccc ("qeth: serialize sysfs-triggered device configurations")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: NAlexandra Winter <wintera@linux.ibm.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

When qeth_dev_layer2_store() - holding the discipline_mutex - waits
inside qeth_l*_remove_device() for a qeth_do_reset() thread to complete,
we can hit a deadlock if qeth_do_reset() concurrently calls
qeth_set_online() and thus tries to aquire the discipline_mutex.

Move the discipline_mutex locking outside of qeth_set_online() and
qeth_set_offline(), and turn the discipline into a parameter so that
callers understand the dependency.

To fix the deadlock, we can now relax the locking:
As already established, qeth_l*_remove_device() waits for
qeth_do_reset() to complete. So qeth_do_reset() itself is under no risk
of having card->discipline ripped out while it's running, and thus
doesn't need to take the discipline_mutex.

Fixes: 9dc48ccc ("qeth: serialize sysfs-triggered device configurations")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: NAlexandra Winter <wintera@linux.ibm.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

All qeth devices have a minimum set of sysfs attributes, and non-OSN
devices share a group of additional attributes. Depending on whether
the device is forced to use a specific discipline, the device_type then
specifies further attributes.

Shift the common attributes into dev->groups, so that the device_type
only contains the discipline-specific attributes. This avoids exposing
the common attributes to the disciplines, and nicely cleans up our
sysfs code.

While replacing the qeth_l*_*_device_attributes() helpers, switch from
sysfs_*_groups() to the more generic device_*_groups().
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix the following coccinelle report:

./drivers/s390/net/qeth_l3_main.c:107:2-4: WARNING: possible condition with no effect (if == else)

Both branches are the same since
commit ab29c480 ("s390/qeth: replace deprecated simple_stroul()"),
so remove them.
Reported-by: NTosk Robot <tencent_os_robot@tencent.com>
Signed-off-by: NKaixu Xia <kaixuxia@tencent.com>
[jwi: point to the commit that introduced this]
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

- Add/delete some blanks, white spaces and braces.
- Fix misindentations.
- Adjust a deprecated header include, and htons() conversion.
- Remove extra 'return' statements.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace our custom version of netdev_name().

Once we started to allocate the netdev at probe time with
commit d3d1b205 ("s390/qeth: allocate netdevice early"), this
stopped working as intended anyway.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The discipline struct is a fixed group of function pointers.
So declare the L2 and L3 disciplines as constant.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For OSA devices that are _not_ configured in prio-queue mode, give users
the option of selecting the number of active TX queues.
This requires setting up the HW queues with a reasonable default QoS
value in the QIB's PQUE parm area.

As with the other device types, we bring up the device with a minimal
number of TX queues for compatibility reasons.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When re-initializing a device, we can hit a situation where
qeth_osa_set_output_queues() detects that it supports more or less
HW TX queues than before. Right now we adjust dev->real_num_tx_queues
from right there, but
1. it's getting more & more complicated to cover all cases, and
2. we can't re-enable the actually expected number of TX queues later
because we lost the needed information.

So keep track of the wanted TX queues (on initial setup, and whenever
its changed via .set_channels), and later use that information when
re-enabling the netdevice.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Clarify which discipline-specific steps are needed to roll back after
error in qeth_l?_set_online(), and which are common to roll back
from qeth_hardsetup_card().

Some steps (cancelling the RX modeset, draining the TX queues) are only
necessary if the netdev was potentially UP before, so move them to the
common qeth_set_offline().
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move duplicated code from the disciplines into the core path.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Originators of cmd IO typically hold the rtnl or conf_mutex to protect
against a concurrent teardown.
Since qeth_set_offline() already holds the conf_mutex, the main reason
why we still care about cancelling pending cmds is so that they release
the rtnl when we need it ourselves.

So move this step a little earlier into the teardown sequence.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The programming of ucast IPs via qeth_l3_modify_ip() is driven
independently from any of our typical locking mechanisms (eg. detaching
the netdevice, or holding the conf_mutex).
So when we inspect the card state to check whether the required cmd IO
should be deferred, there is no protection against concurrent state
changes.

But by slightly re-ordering the teardown sequence, we can rely on the
ip_lock to sufficiently serialize things:

1. when running concurrently to qeth_l3_set_online(), any instance of
   qeth_l3_modify_ip() that aquires the ip_lock _after_
   qeth_l3_recover_ip() will observe the state as CARD_STATE_SOFTSETUP
   and not defer the IO.
2. when running concurrently to qeth_l3_set_offline(), any instance of
   qeth_l3_modify_ip() that aquires the ip_lock _after_
   qeth_l3_clear_ip_htable() will observe the state as CARD_STATE_DOWN
   and defer the IO.

These guarantees in mind, we can now drop the conf_mutex from the
qeth_l3_modify_rxip_vipa() wrapper.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert the remaining occurences in sysfs code to kstrtouint().

While at it move some input parsing out of locked sections, replace an
open-coded clamp() and remove some unnecessary run-time checks for
ipatoe->mask_bits that are already enforced when creating the object.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

card->ipato is currently protected by the conf_mutex. But most users
also hold the ip_lock - in particular qeth_l3_add_ip().

So slightly expand the sections under ip_lock in a few places (to
effectively cover a few error & no-op cases), and then drop the
conf_mutex where it's no longer needed.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

mcast IP objects are allocated within qeth_l3_add_mcast_rtnl(),
with .ref_counter already set to 1 via qeth_l3_init_ipaddr().
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Wait until the QDIO data connection is severed. Otherwise the device
might still be processing the buffers, and end up accessing skb data
that we already freed.

Fixes: 8b5026bc ("s390/qeth: fix qdio teardown after early init error")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Clarify that the 'ipacmd' parameter is an enum, and thus compatible to
what qeth_ipa_alloc_cmd() expects as input.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-throughSigned-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>

Running a RX refill outside of NAPI context is inherently racy, even
though the worker is only started for an entirely idle RX ring.
>From the moment that the worker has replenished parts of the RX ring,
the HW can use those RX buffers, raise an IRQ and cause our NAPI code to
run concurrently to the RX refill worker.

Instead let the worker schedule our NAPI instance, and refill the RX
ring from there. Keeping accurate count of how many buffers still need
to be refilled also removes some quirky arithmetic from the low-level
code.

Fixes: b3332930 ("qeth: add support for af_iucv HiperSockets transport")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To keep track of the addresses programmed from an RX modeset, we have
two separate hashtables (L2: mac_htable, L3: ip_mc_htable).

These are never used at the same time, so unify them into a single
rx_mode_addrs hashtable.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rather than delaying the decision until netdev setup, immediately reject
a device when we discover that it has an unsupported link type
(ie. Token Ring).
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These will be used in a subsequent patch.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In configurations where specific HW offloads are in use, OSA adapters
will raise notifications to their virtual devices about the IP addresses
that currently reside on the same adapter.
Cache these addresses in two RCU-enabled hash tables, and flush the
tables once the relevant HW offload(s) get disabled.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enable the L3 driver's IPv4 address notifier to watch for events on qeth
devices that have been moved into a net namespace. We need to program
those IPs into the HW just as usual, otherwise inbound traffic won't
flow.

Fixes: 6133fb1a ("[NETNS]: Disable inetaddr notifiers in namespaces other than initial.")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The logic that deals with errors from qeth_l3_get_unique_id() is quite
complex: it sets card->unique_id to 0xfffe, additionally flags it as
UNIQUE_ID_NOT_BY_CARD and later takes this flag as cue to not propagate
card->unique_id to dev->dev_id. With dev->dev_id thus holding 0,
addrconf_ifid_eui48() applies its default behaviour.

Get rid of all the special bit masks, and just return the old uid in
case of an error. For the vast majority of cases this will be 0 (and so
we still get the desired default behaviour) - with the rare exception
where qeth_l3_get_unique_id() might have been called earlier but the
initialization then failed at a later point.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To check whether a netdevice has already been registered, look at
NETREG_REGISTERED to replace some hacks I added a while ago.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

z/VM NICs don't offer HW QoS for TX rings. So just use netdev_pick_tx()
to distribute the connections equally over all enabled TX queues.

We start with just 1 enabled TX queue (this matches the typical
configuration without prio-queueing). A follow-on patch will allow users
to enable additional TX queues.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When qeth's napi poll code fails to refill an entirely empty RX ring, it
kicks off buffer_reclaim_work to try again later.

Make sure that this worker is cancelled when setting the qeth device
offline. Otherwise a RX refill action can unexpectedly end up running
concurrently to bigger re-configurations (eg. resizing the buffer pool),
without any locking.

Fixes: b3332930 ("qeth: add support for af_iucv HiperSockets transport")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's good practice to not blindly trust what the HW offers.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: NAlexandra Winter <wintera@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Properly define the cmd's struct to get rid of some casts and accesses
at magic offsets.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: NAlexandra Winter <wintera@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

card->info.unique_id is always 0 for IQD devices, so don't bother with
copying it into the 0-initialized cmd.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: NAlexandra Winter <wintera@linux.ibm.com>
Signed-off-by: NDavid 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: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid 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: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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