Commit Graph

191 Commits

Author SHA1 Message Date
Julian Wiedmann
b0abc4f5df s390/qeth: overhaul ethtool statistics
Accumulate per-TX queue statistics, and increase their size to 64 bit.
Don't bother with enabling/disabling the statistics, the overhead is
negligible.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-15 20:35:29 -08:00
Julian Wiedmann
d896ac62d0 s390/qeth: move ethtool code into its own file
Most of this is self-contained code.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-15 20:35:29 -08:00
Julian Wiedmann
4326b5b461 s390/qeth: reduce ethtool statistics
Counting the number of function calls and the time spent in functions
is best left to proper tracing facilities.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-15 20:35:29 -08:00
Julian Wiedmann
bb92d3f866 s390/qeth: use a static Output Queue array
qeth dynamically allocates an array for storing pointers to its
Output Queue structures. Switch this to a static array - we are
currently limited to 4 Output Queues, so shrinking the qeth_qdio_info
struct by just a few bytes doesn't justify the additional complexity.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-15 20:35:29 -08:00
Julian Wiedmann
4b7ae12216 s390/qeth: allow cmd callbacks to return errnos
Error propagation from cmd callbacks currently works in a way where
qeth_send_control_data_cb() picks the raw HW code from the response,
and the cmd's originator later translates this into an errno.
The callback itself only returns 0 ("done") or 1 ("expect more data").

This is
1. limiting, as the only means for the callback to report an internal
error is to invent pseudo HW codes (such as IPA_RC_ENOMEM), that
the originator then needs to understand. For non-IPA callbacks, we
even provide a separate field in the IO buffer metadata (iob->rc) so
the callback can pass back a return value.
2. fragile, as the originator must take care to not translate any errno
that is returned by qeth's own IO code paths (eg -ENOMEM). Also, any
originator that forgets to translate the HW codes potentially passes
garbage back to its caller. For instance, see
commit 2aa4867198 ("s390/qeth: translate SETVLAN/DELVLAN errors").

Introduce a new model where all HW error translation is done within the
callback, and the callback returns
>  0, if it expects more data (as before)
== 0, on success
<  0, with an errno

Start off with converting all callbacks to the new model that either
a) pass back pseudo HW codes, or b) have a dependency on a specific
HW error code. Also convert c) the one callback that uses iob->rc, and
d) qeth_setadpparms_change_macaddr_cb() so that it can pass back an
error back to qeth_l2_request_initial_mac() even when the cmd itself
was successful.

The old model remains supported: if the callback returns 0, we still
propagate the response's HW error code back to the originator.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12 13:14:24 -05:00
Julian Wiedmann
54daaca702 s390/qeth: cancel cmd on early error
When sending cmds via qeth_send_control_data(), qeth puts the request
on the IO channel and then blocks on the reply object until the response
has been received.

If the IO completes with error, there will never be a response and we
block until the reply-wait hits its timeout. For this case, connect the
request buffer to its reply object, so that we can immediately cancel
the wait.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12 13:14:24 -05:00
Julian Wiedmann
c21532771e s390/qeth: consolidate filling of low-level cmd length fields
The code to fill the IPA length fields is duplicated three times across
the driver:
1. qeth_send_ipa_cmd() sets IPA_CMD_LENGTH, which matches the defaults
   in the IPA_PDU_HEADER template.
2. for OSN, qeth_osn_send_ipa_cmd() bypasses this logic and inserts the
   length passed by the caller.
3. SNMP commands (that can outgrow IPA_CMD_LENGTH) have their own way
   of setting the length fields, via qeth_send_ipa_snmp_cmd().

Consolidate this into qeth_prepare_ipa_cmd(), which all originators of
IPA cmds already call during setup of their cmd. Let qeth_send_ipa_cmd()
pull the length from the cmd instead of hard-coding IPA_CMD_LENGTH.

For now, the SNMP code still needs to fix-up its length fields manually.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12 13:14:24 -05:00
Julian Wiedmann
84dbea461e s390/qeth: reduce data length for ARP cache query
qeth_l3_query_arp_cache_info() indicates a data length that's much
larger than the actual length of its request (ie. the value passed to
qeth_get_setassparms_cmd()). The confusion presumably comes from the
fact that the cmd _response_ can be quite large - but that's no concern
for the initial request IO.

Fixing this up allows us to use the generic qeth_send_ipa_cmd()
infrastructure.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12 13:14:24 -05:00
David S. Miller
a655fe9f19 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
An ipvlan bug fix in 'net' conflicted with the abstraction away
of the IPV6 specific support in 'net-next'.

Similarly, a bug fix for mlx5 in 'net' conflicted with the flow
action conversion in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-08 15:00:17 -08:00
Julian Wiedmann
c0a2e4d10d s390/qeth: conclude all event processing before offlining a card
Work for Bridgeport events is currently placed on a driver-wide
workqueue. If the card is removed and freed while any such work is still
active, this causes a use-after-free.
So put the events on a per-card queue, where we can control their
lifetime. As we also don't want stale events to last beyond an
offline & online cycle, flush this queue when setting the card offline.

Fixes: b4d72c08b3 ("qeth: bridgeport support - basic control")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-04 09:43:48 -08:00
Julian Wiedmann
c2780c1a3f s390/qeth: cancel close_dev work before removing a card
A card's close_dev work is scheduled on a driver-wide workqueue. If the
card is removed and freed while the work is still active, this causes a
use-after-free.
So make sure that the work is completed before freeing the card.

Fixes: 0f54761d16 ("qeth: Support VEPA mode")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-04 09:43:48 -08:00
Julian Wiedmann
5fc692a7ff s390/qeth: remove VLAN tracking for L2 devices
For recovery purposes, qeth keeps track of all registered VIDs. Replace
this by using the infrastructure introduced in
commit 9daae9bd47 ("net: Call add/kill vid ndo on vlan filter feature toggling").

By managing NETIF_F_HW_VLAN_CTAG_FILTER as a hw_feature,
netdev_update_features() will select it from dev->wanted_features
and replay all of the netdevice's VIDs to its ndo_vlan_rx_add_vid()
callback.
z/VM NICs strictly require VLAN registration, so don't expose it as
hw_feature there but add a little hack in qeth_enable_hw_features()
to make things work regardless.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-25 21:23:56 -08:00
Julian Wiedmann
e6e771b3d8 s390/qeth: detach netdevice while card is offline
When a qeth card is offline, it has no connection to the HW. So none of
our control callbacks can run IO against it, and we can only cache the
input (eg a new MAC address) without providing proper feedback to the
caller. In this context, it seems much more reasonable to simply detach
the netdevice and let the kernel reject any interaction with it.

This also makes all sorts of internal state checks and locking obsolete.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-25 21:23:56 -08:00
Julian Wiedmann
e22355ea3f s390/qeth: consolidate open/stop netdev ops
The L2 and L3 code for these ops is almost identical, we only need to
provide a custom ndo_validate_addr() for L2 that checks whether
programming the MAC address succeeded.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-25 21:23:55 -08:00
Julian Wiedmann
d7d18da1f7 s390/qeth: remove card list
Re-implement the card-by-RDEV lookup by using device model concepts, and
remove the now redundant list of all qeth card instances in the system.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:22:23 -08:00
Julian Wiedmann
81ec543939 s390/qeth: unify transmit code
Since commit 82bf5c0867 ("s390/qeth: add support for IPv6 TSO"),
qeth_xmit() also knows how to build TSO packets and is practically
identical to qeth_l3_xmit().
Convert qeth_l3_xmit() into a thin wrapper that merely strips the
L2 header off a packet, and calls qeth_xmit() for the actual
TX processing.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:22:23 -08:00
Julian Wiedmann
5a541f6d00 s390/qeth: handle af_iucv skbs in qeth_l3_fill_header()
Filling the HW header from one single function will make it easier to
rip out all the duplicated transmit code in qeth_l3_xmit(). On top, this
saves one conditional branch in the TSO path.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:22:23 -08:00
Julian Wiedmann
b144b99fff s390/qeth: utilize virtual MAC for Layer2 OSD devices
By default, READ MAC on a Layer2 OSD device returns the adapter's
burnt-in MAC address. Given the default scenario of many virtual devices
on the same adapter, qeth can't make any use of this address and
therefore skips the READ MAC call for this device type.

But in some configurations, the READ MAC command for a Layer2 OSD device
actually returns a pre-provisioned, virtual MAC address. So enable the
READ MAC code to detect this situation, and let the L2 subdriver
call READ MAC for OSD devices.

This also removes the QETH_LAYER2_MAC_READ flag, which protects L2
devices against calling READ MAC multiple times. Instead protect the
whole call to qeth_l2_request_initial_mac().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:22:23 -08:00
Julian Wiedmann
125d7d3011 s390/qeth: sanitize ARP requests
The ARP_{ADD,REMOVE}_ENTRY cmd structs contain reserved fields.
Introduce a common helper that doesn't raw-copy the user-provided data
into the cmd, but only sets those fields that are strictly needed for
the command.

This also sets the correct command length for ARP_REMOVE_ENTRY.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-03 10:44:06 -07:00
Julian Wiedmann
9fae5c3b60 s390/qeth: fix initial operstate
Setting the carrier 'on' for an unregistered netdevice doesn't update
its operstate. Fix this by delaying the update until the netdevice has
been registered.

Fixes: 91cc98f51e ("s390/qeth: remove duplicated carrier state tracking")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-03 10:44:05 -07:00
Julian Wiedmann
30356d0815 s390/qeth: unregister netdevice only when registered
qeth only registers its netdevice when the qeth device is first set
online. Thus a device that has never been set online will trigger
a WARN ("network todo 'hsi%d' but state 0") in unregister_netdev() when
removed.

Fix this by protecting the unregister step, just like we already protect
against repeated registering of the netdevice.

Fixes: d3d1b205e8 ("s390/qeth: allocate netdevice early")
Reported-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-03 10:44:05 -07:00
Julian Wiedmann
e19e5be8b4 s390/qeth: sanitize strings in debug messages
As Documentation/s390/s390dbf.txt states quite clearly, using any
pointer in sprinf-formatted s390dbf debug entries is dangerous.
The pointers are dereferenced whenever the trace file is read from.
So if the referenced data has a shorter life-time than the trace file,
any read operation can result in a use-after-free.

So rip out all hazardous use of indirect data, and replace any usage of
dev_name() and such by the Bus ID number.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-03 10:44:05 -07:00
Julian Wiedmann
0aef8392d2 s390/qeth: add TSO support for L2 devices
Except for the new HW header id, this works just like TSO6 on L3 devices
and reuses all the existing data path support in qeth_xmit().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 11:27:01 -07:00
Julian Wiedmann
82bf5c0867 s390/qeth: add support for IPv6 TSO
This adds TSO6 support for L3 qeth devices.
Just like for standard IPv6 traffic, TSO6 doesn't use IP offload and
thus runs over the normal qeth_xmit() path.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 11:27:01 -07:00
Julian Wiedmann
91cc98f51e s390/qeth: remove duplicated carrier state tracking
The netdevice is always available, apply any carrier state changes to it
without caching them.
On a STARTLAN event (ie. carrier-up), defer updating the state to
qeth_core_hardsetup_card() in the subsequent recovery action.

Also remove the carrier-state checks from the xmit routines. Stopping
transmission on carrier-down is the responsibility of upper-level code
(eg see dev_direct_xmit()).

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 09:56:08 -07:00
Julian Wiedmann
8f6637b878 s390/qeth: pass card pointer in iob callback
This allows us to remove the CARD_FROM_CDEV calls in the iob callbacks.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 09:56:07 -07:00
Julian Wiedmann
4fda335476 s390/qeth: convert layer attribute to enum
While the raw values are fixed due to their use in a sysfs attribute,
we can still use the proper QETH_DISCIPLINE_* enum within the driver.

Also move the initialization into qeth_set_initial_options(), along with
all other user-configurable fields.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 09:56:07 -07:00
Julian Wiedmann
ed47155bdc s390/qeth: fine-tune spinlocks
For quite a lot of code paths it's obvious that they will never run in
IRQ context. So replace their spin_lock_irqsave() calls with
spin_lock_irq().

While at it, get rid of the redundant card pointer in struct qeth_reply
that was used by qeth_send_control_data() to access the card's lock.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
69d7ce80df s390/qeth: remove qeth_hdr_chk_and_bounce()
Restructure the OSN xmit path to handle misaligned HW headers properly,
without shifting the packet data around.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
356156b60a s390/qeth: speed up TSO transmission
Switch TSO over to the faster transmit path, and remove all the unused
old TSO code.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
e517b649b3 s390/qeth: prepare for copy-free TSO transmission
Add all the necessary TSO plumbing to the copy-less transmit path.
This includes calculating the right length of required protocol headers,
and always building a separate buffer element for the TSO headers.

A follow-up patch will then switch TSO traffic over to this path.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
f231dc9dbd s390/qeth: limit csum offload erratum to L3 devices
Combined L3+L4 csum offload is only required for some L3 HW. So for
L2 devices, don't offload the IP header csum calculation.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reference-ID: JUP 394553
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
40e6a22584 s390/qeth: remove qeth_get_elements_no()
Convert the last remaining user of qeth_get_elements_no() to
qeth_count_elements(), so this helper can be removed.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
fc69660bbd s390/qeth: move L2 xmit code to core module
We need the exact same transmit path for non-offload-eligible traffic on
L3 OSAs. So make it accessible from both sub-drivers.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:24 -07:00
Julian Wiedmann
f15cdaf237 s390/qeth: don't restrict qeth_card to DMA memory
Allocating the main qeth_card struct with GFP_DMA blocks us from moving
it into netdev_priv(). But the only reason why we need DMA memory is the
ccw1 structs embedded into each ccw channel. So extract those into
separate allocations, like we already do for the cmd buffers.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 14:02:50 -07:00
Julian Wiedmann
45ca2fd646 s390/qeth: use qeth_setup_ccw() to set up all CCWs
Re-work the helper a little bit, so that it can be used for all CCWs
that qeth issues.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 14:02:50 -07:00
Julian Wiedmann
73657a3e5b s390/qeth: extract helper for MPC protocol type
Just a little code deduplication.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 14:02:50 -07:00
Julian Wiedmann
a7c2f4a332 s390/qeth: add support for constrained HW headers
Some transmit modes require that the HW header is located in the same
page as the initial protocol headers in skb->data. Let callers specify
the size of this contiguous header range, and enforce it when building
the HW header.

While at it, apply some gentle renaming to the relevant L2 code so that
it matches the L3 code.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
ba86ceee9d s390/qeth: merge linearize-check into HW header construction
When checking whether an skb needs to be linearized to fit into an IO
buffer, it's desirable to consider the skb's final size and layout
(ie. after the HW header was added). But a subsequent linearization can
then cause the re-positioned HW header to violate its alignment
restrictions.

Dealing with this situation in two different code paths is quite tricky.
This patch integrates a) linearize-check and b) HW header construction
into one 3 step-sequence:
1. evaluate how the HW header needs to be added (to identify if it takes
   up an additional buffer element), then
2. check if the required buffer elements exceed the device's limit.
   Linearize when necessary and re-evaluate the HW header placement.
3. Add the HW header in the best-possible way:
   a) push, without taking up an additional buffer element
   b) push, but consume another buffer element
   c) allocate a header object from the cache.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
d2a274b25b s390/qeth: add statistics for consumed buffer elements
Nowadays an skb fragment typically spans over multiple pages. So replace
the obsolete, SG-only 'fragments' counter with one that tracks the
consumed buffer elements. This is what actually matters for performance.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
72f219da79 s390/qeth: use core MTU range checking
qeth's ndo_change_mtu() only applies some trivial bounds checking. Set
up dev->min_mtu properly, so that dev_set_mtu() can do this for us.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
8ce7a9e064 s390/qeth: simplify max MTU handling
When the MPC initialization code discovers the HW-specific max MTU,
apply the resulting changes straight to the netdevice.

If this is the device's first initialization, also set its MTU
(HiperSockets: the max MTU; else: a layer-specific default value).
Then cap the current MTU by the new max MTU.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
92d2720969 s390/qeth: don't cache HW port number
The netdevice is always available now, so get the portno from there.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
d3d1b205e8 s390/qeth: allocate netdevice early
Allocation of the netdevice is currently delayed until a qeth card first
goes online. This complicates matters in several places, where we need
to cache values instead of applying them straight to the netdevice.

Improve on this by moving the allocation up to where the qeth card
itself is created. This is also one step in direction of eventually
placing the qeth card into netdev_priv().

In all subsequent code, remove the now redundant checks whether
card->dev is valid.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:29 -07:00
Julian Wiedmann
09960b3a0a s390/qeth: clean up exported symbols
Remove some redundant EXPORTs. While at it, also move some L2-only
prototypes into the proper header file.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12 16:42:39 -07:00
Julian Wiedmann
86c0cdb9e0 s390/qeth: clean up Output Queue selection
Consolidate duplicated code, fix the misuse of RTN_UNSPEC and simplify
the handling of non-unicast traffic on IQD devices.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12 16:42:39 -07:00
Julian Wiedmann
f67a43a73b s390/qeth: remove unused buffer->aob pointer
Except for tracing, the pointer is not used.

At the same time, accessing it from qeth_qdio_output_handler() is racy:
whenever qeth_qdio_cq_handler() gets control, its call to
qeth_qdio_handle_aob() frees the AOB.

So the AOB pointer that qeth_qdio_output_handler() stores into 'buffer'
can go stale at any time, and trigger a use-after-free.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12 16:42:39 -07:00
Julian Wiedmann
d025da9eb1 s390/qeth: consistently re-enable device features
commit e830baa9c3 ("qeth: restore device features after recovery") and
commit ce34435641 ("s390/qeth: rely on kernel for feature recovery")
made sure that the HW functions for device features get re-programmed
after recovery.

But we missed that the same handling is also required when a card is
first set offline (destroying all HW context), and then online again.
Fix this by moving the re-enable action out of the recovery-only path.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-30 21:19:48 +09:00
Julian Wiedmann
ce28867fd2 s390/qeth: don't clobber buffer on async TX completion
If qeth_qdio_output_handler() detects that a transmit requires async
completion, it replaces the pending buffer's metadata object
(qeth_qdio_out_buffer) so that this queue buffer can be re-used while
the data is pending completion.

Later when the CQ indicates async completion of such a metadata object,
qeth_qdio_cq_handler() tries to free any data associated with this
object (since HW has now completed the transfer). By calling
qeth_clear_output_buffer(), it erronously operates on the queue buffer
that _previously_ belonged to this transfer ... but which has been
potentially re-used several times by now.
This results in double-free's of the buffer's data, and failing
transmits as the buffer descriptor is scrubbed in mid-air.

The correct way of handling this situation is to
1. scrub the queue buffer when it is prepared for re-use, and
2. later obtain the data addresses from the async-completion notifier
   (ie. the AOB), instead of the queue buffer.

All this only affects qeth devices used for af_iucv HiperTransport.

Fixes: 0da9581ddb ("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>
2018-06-30 21:19:48 +09:00
Kittipon Meesompop
571f9dd802 s390/qeth: add IPv6 TX checksum offload support
Check if a qeth device supports IPv6 TX checksum offload, and advertise
NETIF_F_IPV6_CSUM accordingly. Add support for setting the relevant bits
in IPv6 packet descriptors.

Currently this has only limited use (ie. UDP, or Jumbo Frames). For any
TCP traffic with a standard MSS, the TCP checksum gets calculated
as part of the linear GSO segmentation.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:49 -04:00