Callbacks for a cmd reply run outside the protection of card->lock, to
allow for additional cmds to be issued & enqueued in parallel.

When qeth_send_control_data() bails out for a cmd without having
received a reply (eg. due to timeout), its callback may concurrently be
processing a reply that just arrived. In this case, the callback
potentially accesses a stale reply->reply_param area that eg. was
on-stack and has already been released.

To avoid this race, add some locking so that qeth_send_control_data()
can (1) wait for a concurrently running callback, and (2) zap any
pending callback that still wants to run.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

The cast type currently gets selected in .ndo_start_xmit, and is then
piped through several layers until it's stored into the HW header.
Push the selection down into qeth_l?_fill_header() to (1) reduce the
number of xmit-wide parameters, and (2) merge the two route validation
checks into just one.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As follow-up to commit 0cd6783d ("s390/qeth: check dst entry before use"),
consolidate the dst_check() logic into a single helper and add a wrapper
around the cast type selection.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use napi_gro_receive() to pass up all types of packets that a L3 device
may receive.
1) For proper L2 packets received by the IQD sniffer, this is the
   obvious thing to do.
2) For af_iucv (which doesn't provide a GRO assist), the GRO code will
   transparently fall back to netif_receive_skb(). So there's no need to
   special-case this traffic in our code.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

De-duplicate the pm callback implementations from the two sub-drivers,
replacing them with core helpers that delegate to the .set_online and
.set_offline callbacks.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Apply some cleanups to qeth_snmp_command() and its callback:
1. when accessing the user data, use the proper struct instead of
   hard-coded offsets. Also copy the request data straight into the
   allocated cmd, skipping the extra memdup_user() to a tmp buffer.
2. capping the request length is no longer needed, the same check gets
   applied at a base level in qeth_alloc_cmd().
3. clean up some duplicated (and misindented) trace statements.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that all cmds are dynamically allocated, the code for static cmd
buffers can go away entirely. Resulting in a nice reduction of
code/data size & complexity, while removing the risk that
qeth_clear_cmd_buffers() releases cmds that are still in-flight.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The base MPC cmds are the last remaining user of the static cmd buffers.
Port them over to use dynamic allocation, and stop backing the write
channel's cmd buffers with pages.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The VNICC code is somewhat quirky in that it defers the whole cmd setup
to a common helper qeth_l2_vnicc_request(). Some of the cmd specifics
are then passed in via parameter, while others are simply hard-coded.

Split the whole machinery up into the usual format: one helper that
allocates the cmd & fills in the common fields, while all the cmd
originators take care of their sub-cmd type specific work.
This makes it much easier to calculate the cmd's precise length, and
reduces code complexity.
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>

Add a new wrapper that allocates DIAG cmds of the right size, and fills
in the common fields.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch converts the adapter, assist and bridgeport cmd paths to
dynamic allocation. Most of the work is about re-organizing the cmd
headers, calculating the correct cmd length, and filling in the right
value in the sub-cmd's length field.

Since we now also set the correct length for cmds that are not reflected
by a fixed struct (ie SNMP), we can remove the work-around from
qeth_snmp_command().
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For code that uses qeth_send_simple_setassparms_prot(), we currently
can't differentiate whether the cmd should contain (1) no parameter, or
(2) a 4-byte parameter with value 0.
At the moment this doesn't cause any trouble. But when using dynamically
allocated cmds, we need to know whether to allocate & transmit an
additional 4 bytes of zeroes.
So instead of the raw parameter value, pass a parameter pointer
(or NULL) to qeth_send_simple_setassparms_prot().
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch reduces the usage of the write channel's static cmd buffers,
by dynamically allocating all simple IPA cmds (eg. STARTLAN, SETVMAC).
It also converts the OSN path.

Doing so requires some changes to how we calculate the cmd length.
Currently when building IPA cmds, we're quite generous in how much data
we send down to the device (basically the size of the biggest cmd we
know). This is no real concern at the moment, since the static cmd
buffers are backed with zeroed pages. But for dynamic allocations, the
exact length matters. So this patch also adds the needed length
calculations to each cmd path.

Commands that have multiple subtypes (eg. SETADP) of differing length
will be converted with follow-up patches.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We statically allocate 8 cmd buffers on the read channel, when the only
IO left that's still using them is the long-running READ.
Replace this with a single allocated cmd, that gets restarted whenever
the READ completed.

This introduces refcounting for allocated cmds, so that the READ cmd can
survive the IO completion.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current IDX sequence first sends one WRITE cmd to activate the
device, and then sends a second cmd that READs the response.

Using qeth_alloc_cmd(), we can combine this into a single IO with two
command-chained CCWs.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The RCD code is the last remaining IO path that doesn't use the
qeth_send_control_data() infrastructure. Doing so allows us to remove
all sorts of custom state machinery and logic in the IRQ handler.

Instead of introducing statically allocated cmd buffers for this single
IO on the data channel, use the new qeth_alloc_cmd() helper.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

qeth currently uses a fixed set of statically allocated cmd buffers for
the read and write IO channels. This (1) doesn't play well with the single
RCD cmd we need to issue on the data channel, (2) doesn't provide the
necessary flexibility for certain IDX improvements, and (3) is also rather
wasteful since the buffers are idle most of the time.

Add a new type of cmd buffer that is dynamically allocated, and keeps
its ccw chain in the DMA data area. Since this touches most callers of
qeth_setup_ccw(), also add a new CCW flags parameter for future usage.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Each cmd buffer maintains a pointer to the IO channel that it was/will
be issued on. So when dealing with cmd buffers, we don't need to pass
around a separate channel pointer.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The vast majority of SETUP-classified trace entries can be moved to
their device-specific trace file. This reduces pollution of the global
SETUP file, and provides a consistent trace view of all activity on the
device.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

OSN currently provides a custom code path to submit IPA cmds, without
waiting for the cmd response. Replace it with qeth_send_ipa_cmd(), which
uses the common qeth_send_control_data() IO infrastructure.

By setting a custom iob->callback, we can now provide feedback to the
caller about whether the cmd has been successfully submitted to HW.
Since the callback then immediately wakes up the reply-waiter object, we
maintain the old behaviour of returning early without waiting for the
response.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The basic MPC initialization sequence is strictly sequential, and
waiting for an available cmd buffer should never be necessary.
So this change only affects the OSN path, where dangling waiters on an
unbounded wait_event() are not desirable. Switch to qeth_get_buffers(),
and let OSN callers deal with -ENOMEM.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When called from qeth_core_probe_device(), qeth_determine_capabilities()
initializes the device's BLKT defaults. From all other callers, the
ccw_device has already been set online and the BLKT setting is skipped.

Clean this up by extracting the BLKT setting into a separate helper that
gets called from the right place.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The completion of a pending READ cmd is processed via
qeth_issue_next_read_cb(). Let this callback also start the next READ
cmd, instead of hardcoding that step into the IRQ handler.

While at it remove the check of the channel state,
__qeth_issue_next_read() already does this.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the tear down sequence in qeth_l?_stop_card() has finished, the
card is guaranteed to be in DOWN state and we don't have to check for
it again.
With this insight we can also remove the redundant setting of
card->state in qeth_l?_set_online()'s error path.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Slightly reduce the complexity of the core xmit path, by replacing some
open-coded logic with the corresponding helpers.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Current code suppresses debug entries when an TX buffer completes in
ERROR state with no error indication set in SBALF15.
This was introduced back with
commit 58490f18 ("qeth: HiperSockets SIGA retry support on CC=2.").
But qeth no longer retries after CC=2, and this sort of suppression
make no sense anymore. Remove it.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

netif_set_real_num_tx_queues() can return an error, deal with it.

Fixes: 73dc2daf ("s390/qeth: add TX multiqueue support for OSA devices")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enabling sysfs attribute bridge_hostnotify triggers a series of udev events
for the MAC addresses of all currently connected peers. In case no VLAN is
set for a peer, the device reports the corresponding MAC addresses with
VLAN ID 4096. This currently results in attribute VLAN=4096 for all
non-VLAN interfaces in the initial series of events after host-notify is
enabled.

Instead, no VLAN attribute should be reported in the udev event for
non-VLAN interfaces.

Only the initial events face this issue. For dynamic changes that are
reported later, the device uses a validity flag.

This also changes the code so that it now sets the VLAN attribute for
MAC addresses with VID 0. On Linux, no qeth interface will ever be
registered with VID 0: Linux kernel registers VID 0 on all network
interfaces initially, but qeth will drop .ndo_vlan_rx_add_vid for VID 0.
Peers with other OSs could register MACs with VID 0.

Fixes: 9f48b9db ("qeth: bridgeport support - address notifications")
Signed-off-by: NAlexandra Winter <wintera@linux.ibm.com>
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While qeth_l3 uses netif_keep_dst() to hold onto the dst, a skb's dst
may still have been obsoleted (via dst_dev_put()) by the time that we
end up using it. The dst then points to the loopback interface, which
means the neighbour lookup in qeth_l3_get_cast_type() determines a bogus
cast type of RTN_BROADCAST.
For IQD interfaces this causes us to place such skbs on the wrong
HW queue, resulting in TX errors.

Fix-up the various call sites to first validate the dst entry with
dst_check(), and fall back accordingly.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When selecting the cast type of a neighbourless IPv4 skb (eg. on a raw
socket), qeth_l3 falls back to the packet's destination IP address.
For this case we should classify traffic sent to 255.255.255.255 as
broadcast.
This fixes DHCP requests, which were misclassified as unicast
(and for IQD interfaces thus ended up on the wrong HW queue).
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Formatting of Kconfig files doesn't look so pretty, so just
take damp cloth and clean it up.
Signed-off-by: NEnrico Weigelt, metux IT consult <info@metux.net>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

ISM devices are special in how they access PCI memory space. Provide
wrappers for handling commands to the device. No functional change.
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This is a preparation patch for usage of new pci instructions.
No functional change.
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

When building the L3 HW header for non-IP packets, trust the cast type
that was passed as parameter. qeth_l3_get_cast_type() has most likely
also used h_dest to determine the cast type, so we get the same
result, and can remove that duplicated code.
In the unlikely case that we would get a _different_ cast type, then
that's based off a route lookup and should be considered authoritative.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This de-duplicates the L2 and L3 cast-type code, and makes the L2 code
a bit more robust by removing the fragile assumption that skb->data
always points to the Ethernet Header. This would break in code paths
where we pushed the HW header onto the skb.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The QETH_MAX_BUFFER_ELEMENTS() macro effectively returns a constant
value. To avoid some redundant pointer chasing and computations in the
xmit hot path, cache this value in the queue struct.

Take this as opportunity to shrink some of the queue struct's fields to
their appropriate value range, slightly reducing its total size.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On the first initialization of a queue, its Output Buffers are in a
clean state with no attached resources. On every subsequent
initialization, qeth_l?_stop_card() has previously put them in a clean
state via qeth_drain_output_queues(). So the call to
qeth_clear_output_buffer() is redundant and can be removed.

While at it, move the initialization of the queue's card pointer into
the queue allocation. It never changes afterwards.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have helper macros for all possible device types, replace all
remaining open-coded accesses to the type fields.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We don't keep track of Input Buffer states, so remove the comments that
make it sound like the qeth_qdio_buffer_states enum applies to
Input Buffers.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's unclear what exact purpose this seqno may have served in the past.
But it's certainly no longer used anymore, as the following
napi_gro_receive() will straight away clear this part of the cb again.
Suggested-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>