s390/qeth: Don't call dev_close/dev_open (DOWN/UP)

dev_close() and dev_open() are issued to change the interface state to DOWN
or UP (dev->flags IFF_UP). When the netdev is set DOWN it loses e.g its

s390/qeth: Don't call dev_close/dev_open (DOWN/UP)

dev_close() and dev_open() are issued to change the interface state to DOWN
or UP (dev->flags IFF_UP). When the netdev is set DOWN it loses e.g its
Ipv6 addresses and routes. We don't want this in cases of device recovery
(triggered by hardware or software) or when the qeth device is set
offline.

Setting a qeth device offline or online and device recovery actions call
netif_device_detach() and/or netif_device_attach(). That will reset or
set the LOWER_UP indication i.e. change the dev->state Bit
__LINK_STATE_PRESENT. That is enough to e.g. cause bond failovers, and
still preserves the interface settings that are handled by the network
stack.

Don't call dev_open() nor dev_close() from the qeth device driver. Let the
network stack handle this.

Fixes: d4560150cb47 ("s390/qeth: call dev_close() during recovery")
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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qeth: remove a copy of the NAPI_POLL_WEIGHT define

Defining local versions of NAPI_POLL_WEIGHT with the same
values in the drivers just makes refactoring harder.

Signed-off-by: Jakub Kicinski <kuba

qeth: remove a copy of the NAPI_POLL_WEIGHT define

Defining local versions of NAPI_POLL_WEIGHT with the same
values in the drivers just makes refactoring harder.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: fine-tune .ndo_select_queue()

Avoid a conditional branch for L2 devices when selecting the TX queue,
and have shared logic for OSA devices.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.

s390/qeth: fine-tune .ndo_select_queue()

Avoid a conditional branch for L2 devices when selecting the TX queue,
and have shared logic for OSA devices.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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s390/qeth: add __printf format attribute to qeth_dbf_longtext

Allow the compiler to recognize and check format strings and parameters.

As reported with allmodconfig and W=1:

drivers/s390/net/qeth_

s390/qeth: add __printf format attribute to qeth_dbf_longtext

Allow the compiler to recognize and check format strings and parameters.

As reported with allmodconfig and W=1:

drivers/s390/net/qeth_core_main.c: In function ‘qeth_dbf_longtext’:
drivers/s390/net/qeth_core_main.c:6190:9: error: function ‘qeth_dbf_longtext’ might be a candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format]
6190 | vsnprintf(dbf_txt_buf, sizeof(dbf_txt_buf), fmt, args);
| ^~~~~~~~~

Acked-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: don't keep track of Input Queue count

The only actual user of qdio.no_input_queues is qeth_qdio_establish(),
and there we already have full awareness of the current Input Queue
configurat

s390/qeth: don't keep track of Input Queue count

The only actual user of qdio.no_input_queues is qeth_qdio_establish(),
and there we already have full awareness of the current Input Queue
configuration (1 RX queue, plus potentially 1 TX Completion queue).

So avoid this state tracking, and the ambiguity it brings with it.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: remove .do_ioctl() callback from driver discipline

With commit 18787eeebd71 ("qeth: use ndo_siocdevprivate") this callback
is now actually used to handle transport mode-specific _private_

s390/qeth: remove .do_ioctl() callback from driver discipline

With commit 18787eeebd71 ("qeth: use ndo_siocdevprivate") this callback
is now actually used to handle transport mode-specific _private_ ioctls.

We only have such ioctls for L3 devices. So wire up a L3-specific
.ndo_siocdevprivate() callback that handles those ioctls, and defers to
the core qeth_siocdevprivate() for all other private ioctls.

This takes the discipline one step closer to its original purpose of
providing an internal extension for the qeth_core_ccwgroup_driver.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: Fix deadlock in remove_discipline

Problem: qeth_close_dev_handler is a worker that tries to acquire
card->discipline_mutex via drv->set_offline() in ccwgroup_set_offline().
Since commit b

s390/qeth: Fix deadlock in remove_discipline

Problem: qeth_close_dev_handler is a worker that tries to acquire
card->discipline_mutex via drv->set_offline() in ccwgroup_set_offline().
Since commit b41b554c1ee7
("s390/qeth: fix locking for discipline setup / removal")
qeth_remove_discipline() is called under card->discipline_mutex and
cancels the work and waits for it to finish.

STOPLAN reception with reason code IPA_RC_VEPA_TO_VEB_TRANSITION is the
only situation that schedules close_dev_work. In that situation scheduling
qeth recovery will also result in an offline interface, when resetting the
isolation mode fails, if the external switch is still set to VEB.
And since commit 0b9902c1fcc5 ("s390/qeth: fix deadlock during recovery")
qeth recovery does not aquire card->discipline_mutex anymore.

So we accept the longer pathlength of qeth_schedule_recovery in this
error situation and re-use the existing function.

As a side-benefit this changes the hwtrap to behave like during recovery
instead of like during a user-triggered set_offline.

Fixes: b41b554c1ee7 ("s390/qeth: fix locking for discipline setup / removal")
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Acked-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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qeth: use ndo_siocdevprivate

qeth has both standard MII ioctls and custom SIOCDEVPRIVATE ones,
all of which work correctly with compat user space.

Move the private ones over to the new ndo_siocdevp

qeth: use ndo_siocdevprivate

qeth has both standard MII ioctls and custom SIOCDEVPRIVATE ones,
all of which work correctly with compat user space.

Move the private ones over to the new ndo_siocdevprivate callback.

Cc: Julian Wiedmann <jwi@linux.ibm.com>
Cc: Karsten Graul <kgraul@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: clean up device_type management

qeth uses three device_type structs - a generic one, and one for each
sub-driver (which is used for fixed-layer devices only). Instead of
exporting these d

s390/qeth: clean up device_type management

qeth uses three device_type structs - a generic one, and one for each
sub-driver (which is used for fixed-layer devices only). Instead of
exporting these device_types back&forth between the driver's modules,
make all the logic self-contained within the sub-drivers.

On disc->setup() they either install their own device_type, or add the
sysfs attributes that are missing in the generic device_type. Later on
disc->remove() these attributes are removed again from any device that
has the generic device_type.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: remove OSN support

Commit fb64de1bc36c ("s390/qeth: phase out OSN support") spelled out
why the OSN support in qeth is in a bad shape, and put any remaining
interested parties on notice t

s390/qeth: remove OSN support

Commit fb64de1bc36c ("s390/qeth: phase out OSN support") spelled out
why the OSN support in qeth is in a bad shape, and put any remaining
interested parties on notice to speak up before it gets ripped out.

It's 2021 now, so make true on that promise and remove all the
OSN-specific parts from qeth. This also means that we no longer need to
export various parts of the cmd & data path internals to the L2 driver.

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>

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s390/qeth: shrink TX buffer struct

Convert the large boolean array into a bitmap, this substantially
reduces the struct's size. While at it also clarify the naming.

Signed-off-by: Julian Wiedmann <

s390/qeth: shrink TX buffer struct

Convert the large boolean array into a bitmap, this substantially
reduces the struct's size. While at it also clarify the naming.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: remove TX buffer's pointer to its queue

qeth_tx_complete_buf() is the only remaining user of buf->q, and the
callers can easily provide this as a parameter instead.

Signed-off-by: Julian

s390/qeth: remove TX buffer's pointer to its queue

qeth_tx_complete_buf() is the only remaining user of buf->q, and the
callers can easily provide this as a parameter instead.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: remove QAOB's pointer to its TX buffer

Maintaining a pointer inside the aob's user-definable area is fragile
and unnecessary. At this stage we only need it to overload the buffer's
state

s390/qeth: remove QAOB's pointer to its TX buffer

Maintaining a pointer inside the aob's user-definable area is fragile
and unnecessary. At this stage we only need it to overload the buffer's
state field, and to access the buffer's TX queue.

The first part is easily solved by tracking the aob's state within the
aob itself. This also feels much cleaner and self-contained.
For enabling the access to the associated TX queue, we can store the
queue's index in the aob.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: consolidate completion of pending TX buffers

With commit 396c100472dd ("s390/qdio: let driver manage the QAOB")
a pending TX buffer now has access to its associated QAOB during
TX complet

s390/qeth: consolidate completion of pending TX buffers

With commit 396c100472dd ("s390/qdio: let driver manage the QAOB")
a pending TX buffer now has access to its associated QAOB during
TX completion processing. We can thus reduce the amount of work & state
propagation that needs to be done by qeth_qdio_handle_aob().

Move all this logic into the respective TX completion paths. Doing so
even allows us to determine more precise TX_NOTIFY_* values via
qeth_compute_cq_notification(aob->aorc, ...).

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: unify the tracking of active cmds on ccw device

We have one field to track _whether_ a cmd is active on a ccw device
('irq_pending'), and one to track _which_ cmd it is ('active_cmd').

G

s390/qeth: unify the tracking of active cmds on ccw device

We have one field to track _whether_ a cmd is active on a ccw device
('irq_pending'), and one to track _which_ cmd it is ('active_cmd').

Get rid of the irq_pending field, by testing active_cmd for NULL.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: also use TX NAPI for non-IQD devices

Set scan_threshold = 0 to opt out from the qdio layer's internal tasklet
& timer mechanism for TX completions, and replace it with the TX NAPI
infrast

s390/qeth: also use TX NAPI for non-IQD devices

Set scan_threshold = 0 to opt out from the qdio layer's internal tasklet
& timer mechanism for TX completions, and replace it with the TX NAPI
infrastructure that qeth already uses for IQD devices. This avoids the
fragile logic in qdio_check_output_queue(), enables tighter integration
and gives us more tuning options via ethtool in the future.

For now we continue to apply the same policy as the qdio layer:
scan for completions if 32 TX buffers are in use, or after 1 sec.
A re-scan is done after 10 sec, but only if no TX interrupt is pending.

With scan_threshold = 0 we no longer get TX completion scans from
within qdio_get_next_buffers(). So trigger these manually in qeth_poll()
and in the RX path switch to the equivalent qdio_inspect_queue().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: count TX completion interrupts

While the qdio layer already tracks the number of HW interrupts for a
device, there's value in understanding how many of them have been
raised due to our TX

s390/qeth: count TX completion interrupts

While the qdio layer already tracks the number of HW interrupts for a
device, there's value in understanding how many of them have been
raised due to our TX completion logic.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qdio: let driver manage the QAOB

We are spending way too much effort on qdio-internal bookkeeping for
QAOB management & caching, and it's still not robust. Once qdio's
TX path has detached the

s390/qdio: let driver manage the QAOB

We are spending way too much effort on qdio-internal bookkeeping for
QAOB management & caching, and it's still not robust. Once qdio's
TX path has detached the QAOB from a PENDING buffer, we lost all
track of it until it shows up in a CQ notification again. So if the
device is torn down before that notification arrives, we leak the QAOB.

Just have the driver take care of it, and simply pass down a QAOB if
they want a TX with async-completion capability. For a buffer in PENDING
state that requires the QAOB for final completion, qeth can now also try
to recycle the buffer's QAOB rather than unconditionally freeing it.

This also eliminates the qdio_outbuf_state array, which was only needed
to transfer the aob->user1 tag from the driver to the qdio layer.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

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s390/qeth: improve completion of pending TX buffers

The current design attaches a pending TX buffer to a custom
single-linked list, which is anchored at the buffer's slot on the
TX ring. The buffer

s390/qeth: improve completion of pending TX buffers

The current design attaches a pending TX buffer to a custom
single-linked list, which is anchored at the buffer's slot on the
TX ring. The buffer is then checked for final completion whenever
this slot is processed during a subsequent TX NAPI poll cycle.

But if there's insufficient traffic on the ring, we might never make
enough progress to get back to this ring slot and discover the pending
buffer's final TX completion. In particular if this missing TX
completion blocks the application from sending further traffic.

So convert the custom single-linked list code to a per-queue list_head,
and scan this list on every TX NAPI cycle.

Fixes: 0da9581ddb0f ("qeth: exploit asynchronous delivery of storage blocks")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: remove qeth_get_ip_version()

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_* ev

s390/qeth: remove qeth_get_ip_version()

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: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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s390/qeth: clean up load/remove code for disciplines

We have two usage patterns:
1. get & ->setup() a new discipline, or
2. ->remove() & put the currently loaded one.

Add corresponding helpers that

s390/qeth: clean up load/remove code for disciplines

We have two usage patterns:
1. get & ->setup() a new discipline, or
2. ->remove() & put the currently loaded one.

Add corresponding helpers that hide the internals & error handling.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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s390/qeth: fix deadlock during recovery

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 dead

s390/qeth: fix deadlock during recovery

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: 9dc48ccc68b9 ("qeth: serialize sysfs-triggered device configurations")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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s390/qeth: remove QETH_QDIO_BUF_HANDLED_DELAYED state

Reuse the QETH_QDIO_BUF_EMPTY state to indicate that a TX buffer has
been completed with a QAOB notification, and may be cleaned up by
qeth_clea

s390/qeth: remove QETH_QDIO_BUF_HANDLED_DELAYED state

Reuse the QETH_QDIO_BUF_EMPTY state to indicate that a TX buffer has
been completed with a QAOB notification, and may be cleaned up by
qeth_cleanup_handled_pending().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: use dev->groups for common sysfs attributes

All qeth devices have a minimum set of sysfs attributes, and non-OSN
devices share a group of additional attributes. Depending on whether
the d

s390/qeth: use dev->groups for common sysfs attributes

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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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s390/qeth: don't call INIT_LIST_HEAD() on iob's list entry

INIT_LIST_HEAD() only needs to be called on actual list heads.
While at it clarify the naming of the field.

Suggested-by: Vasily Gorbik <g

s390/qeth: don't call INIT_LIST_HEAD() on iob's list entry

INIT_LIST_HEAD() only needs to be called on actual list heads.
While at it clarify the naming of the field.

Suggested-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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