Commit Graph

4535 Commits

Author SHA1 Message Date
Linus Torvalds 237f83dfbe Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Some highlights from this development cycle:

   1) Big refactoring of ipv6 route and neigh handling to support
      nexthop objects configurable as units from userspace. From David
      Ahern.

   2) Convert explored_states in BPF verifier into a hash table,
      significantly decreased state held for programs with bpf2bpf
      calls, from Alexei Starovoitov.

   3) Implement bpf_send_signal() helper, from Yonghong Song.

   4) Various classifier enhancements to mvpp2 driver, from Maxime
      Chevallier.

   5) Add aRFS support to hns3 driver, from Jian Shen.

   6) Fix use after free in inet frags by allocating fqdirs dynamically
      and reworking how rhashtable dismantle occurs, from Eric Dumazet.

   7) Add act_ctinfo packet classifier action, from Kevin
      Darbyshire-Bryant.

   8) Add TFO key backup infrastructure, from Jason Baron.

   9) Remove several old and unused ISDN drivers, from Arnd Bergmann.

  10) Add devlink notifications for flash update status to mlxsw driver,
      from Jiri Pirko.

  11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.

  12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.

  13) Various enhancements to ipv6 flow label handling, from Eric
      Dumazet and Willem de Bruijn.

  14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
      der Merwe, and others.

  15) Various improvements to axienet driver including converting it to
      phylink, from Robert Hancock.

  16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.

  17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
      Radulescu.

  18) Add devlink health reporting to mlx5, from Moshe Shemesh.

  19) Convert stmmac over to phylink, from Jose Abreu.

  20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
      Shalom Toledo.

  21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.

  22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.

  23) Track spill/fill of constants in BPF verifier, from Alexei
      Starovoitov.

  24) Support bounded loops in BPF, from Alexei Starovoitov.

  25) Various page_pool API fixes and improvements, from Jesper Dangaard
      Brouer.

  26) Just like ipv4, support ref-countless ipv6 route handling. From
      Wei Wang.

  27) Support VLAN offloading in aquantia driver, from Igor Russkikh.

  28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.

  29) Add flower GRE encap/decap support to nfp driver, from Pieter
      Jansen van Vuuren.

  30) Protect against stack overflow when using act_mirred, from John
      Hurley.

  31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.

  32) Use page_pool API in netsec driver, Ilias Apalodimas.

  33) Add Google gve network driver, from Catherine Sullivan.

  34) More indirect call avoidance, from Paolo Abeni.

  35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.

  36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.

  37) Add MPLS manipulation actions to TC, from John Hurley.

  38) Add sending a packet to connection tracking from TC actions, and
      then allow flower classifier matching on conntrack state. From
      Paul Blakey.

  39) Netfilter hw offload support, from Pablo Neira Ayuso"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
  net/mlx5e: Return in default case statement in tx_post_resync_params
  mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
  net: dsa: add support for BRIDGE_MROUTER attribute
  pkt_sched: Include const.h
  net: netsec: remove static declaration for netsec_set_tx_de()
  net: netsec: remove superfluous if statement
  netfilter: nf_tables: add hardware offload support
  net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
  net: flow_offload: add flow_block_cb_is_busy() and use it
  net: sched: remove tcf block API
  drivers: net: use flow block API
  net: sched: use flow block API
  net: flow_offload: add flow_block_cb_{priv, incref, decref}()
  net: flow_offload: add list handling functions
  net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
  net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
  net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
  net: flow_offload: add flow_block_cb_setup_simple()
  net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
  net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
  ...
2019-07-11 10:55:49 -07:00
Linus Torvalds 1758feddb0 s390 updates for the 5.3 merge window
- Improve stop_machine wait logic: replace cpu_relax_yield call in generic
    stop_machine function with a weak stop_machine_yield function. This is
    overridden on s390, which yields the current cpu to the neighbouring cpu
    after a couple of retries, instead of blindly giving up the cpu to the
    hipervisor. This significantly improves stop_machine performance on s390 in
    overcommitted scenarios.
    This includes common code changes which have been Acked by Peter Zijlstra
    and Thomas Gleixner.
 
  - Improve jump label transformation speed: transform jump labels without
    using stop_machine.
 
  - Refactoring of the vfio-ccw cp handling, simplifying the code and
    avoiding unneeded allocating/copying.
 
  - Various vfio-ccw fixes (ccw translation, state machine).
 
  - Add support for vfio-ap queue interrupt control in the guest.
    This includes s390 kvm changes which have been Acked by Christian
    Borntraeger.
 
  - Add protected virtualization support for virtio-ccw.
 
  - Enforce both CONFIG_SMP and CONFIG_HOTPLUG_CPU, which allows to remove some
    code which most likely isn't working at all, besides that s390 didn't even
    compile for !CONFIG_SMP.
 
  - Support for special flagged EP11 CPRBs for zcrypt.
 
  - Handle PCI devices with no support for new MIO instructions.
 
  - Avoid KASAN false positives in reworked stack unwinder.
 
  - Couple of fixes for the QDIO layer.
 
  - Convert s390 specific documentation to ReST format.
 
  - Let s390 crypto modules return -ENODEV instead of -EOPNOTSUPP if hardware is
    missing. This way our modules behave like most other modules and which is
    also what systemd's systemd-modules-load.service expects.
 
  - Replace defconfig with performance_defconfig, so there is one config file
    less to maintain.
 
  - Remove the SCLP call home device driver, which was never useful.
 
  - Cleanups all over the place.
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Merge tag 's390-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Improve stop_machine wait logic: replace cpu_relax_yield call in
   generic stop_machine function with a weak stop_machine_yield
   function. This is overridden on s390, which yields the current cpu to
   the neighbouring cpu after a couple of retries, instead of blindly
   giving up the cpu to the hipervisor. This significantly improves
   stop_machine performance on s390 in overcommitted scenarios.

   This includes common code changes which have been Acked by Peter
   Zijlstra and Thomas Gleixner.

 - Improve jump label transformation speed: transform jump labels
   without using stop_machine.

 - Refactoring of the vfio-ccw cp handling, simplifying the code and
   avoiding unneeded allocating/copying.

 - Various vfio-ccw fixes (ccw translation, state machine).

 - Add support for vfio-ap queue interrupt control in the guest. This
   includes s390 kvm changes which have been Acked by Christian
   Borntraeger.

 - Add protected virtualization support for virtio-ccw.

 - Enforce both CONFIG_SMP and CONFIG_HOTPLUG_CPU, which allows to
   remove some code which most likely isn't working at all, besides that
   s390 didn't even compile for !CONFIG_SMP.

 - Support for special flagged EP11 CPRBs for zcrypt.

 - Handle PCI devices with no support for new MIO instructions.

 - Avoid KASAN false positives in reworked stack unwinder.

 - Couple of fixes for the QDIO layer.

 - Convert s390 specific documentation to ReST format.

 - Let s390 crypto modules return -ENODEV instead of -EOPNOTSUPP if
   hardware is missing. This way our modules behave like most other
   modules and which is also what systemd's systemd-modules-load.service
   expects.

 - Replace defconfig with performance_defconfig, so there is one config
   file less to maintain.

 - Remove the SCLP call home device driver, which was never useful.

 - Cleanups all over the place.

* tag 's390-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (83 commits)
  docs: s390: s390dbf: typos and formatting, update crash command
  docs: s390: unify and update s390dbf kdocs at debug.c
  docs: s390: restore important non-kdoc parts of s390dbf.rst
  vfio-ccw: Fix the conversion of Format-0 CCWs to Format-1
  s390/pci: correctly handle MIO opt-out
  s390/pci: deal with devices that have no support for MIO instructions
  s390: ap: kvm: Enable PQAP/AQIC facility for the guest
  s390: ap: implement PAPQ AQIC interception in kernel
  vfio: ap: register IOMMU VFIO notifier
  s390: ap: kvm: add PQAP interception for AQIC
  s390/unwind: cleanup unused READ_ONCE_TASK_STACK
  s390/kasan: avoid false positives during stack unwind
  s390/qdio: don't touch the dsci in tiqdio_add_input_queues()
  s390/qdio: (re-)initialize tiqdio list entries
  s390/dasd: Fix a precision vs width bug in dasd_feature_list()
  s390/cio: introduce driver_override on the css bus
  vfio-ccw: make convert_ccw0_to_ccw1 static
  vfio-ccw: Remove copy_ccw_from_iova()
  vfio-ccw: Factor out the ccw0-to-ccw1 transition
  vfio-ccw: Copy CCW data outside length calculation
  ...
2019-07-08 10:06:12 -07:00
Eric Farman c382cbc6db vfio-ccw: Fix the conversion of Format-0 CCWs to Format-1
When processing Format-0 CCWs, we use the "len" variable as the
number of CCWs to convert to Format-1.  But that variable
contains zero here, and is not a meaningful CCW count until
ccwchain_calc_length() returns.  Since that routine requires and
expects Format-1 CCWs to identify the chaining behavior, the
format conversion must be done first.

Convert the 2KB we copied even if it's more than we need.

Fixes: 7f8e89a8f2 ("vfio-ccw: Factor out the ccw0-to-ccw1 transition")
Reported-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190702180928.18113-1-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-07-05 07:58:53 +02:00
Pierre Morel ec89b55e3b s390: ap: implement PAPQ AQIC interception in kernel
We register a AP PQAP instruction hook during the open
of the mediated device. And unregister it on release.

During the probe of the AP device, we allocate a vfio_ap_queue
structure to keep track of the information we need for the
PQAP/AQIC instruction interception.

In the AP PQAP instruction hook, if we receive a demand to
enable IRQs,
- we retrieve the vfio_ap_queue based on the APQN we receive
  in REG1,
- we retrieve the page of the guest address, (NIB), from
  register REG2
- we retrieve the mediated device to use the VFIO pinning
  infrastructure to pin the page of the guest address,
- we retrieve the pointer to KVM to register the guest ISC
  and retrieve the host ISC
- finaly we activate GISA

If we receive a demand to disable IRQs,
- we deactivate GISA
- unregister from the GIB
- unpin the NIB

When removing the AP device from the driver the device is
reseted and this process unregisters the GISA from the GIB,
and unpins the NIB address then we free the vfio_ap_queue
structure.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Acked-by: Tony Krowiak <akrowiak@linux.ibm.com>
Acked-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-02 16:00:28 +02:00
Pierre Morel 62e358ce58 vfio: ap: register IOMMU VFIO notifier
To be able to use the VFIO interface to facilitate the
mediated device memory pinning/unpinning we need to register
a notifier for IOMMU.

While we will start to pin one guest page for the interrupt indicator
byte, this is still ok with ballooning as this page will never be
used by the guest virtio-balloon driver.
So the pinned page will never be freed. And even a broken guest does
so, that would not impact the host as the original page is still
in control by vfio.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Acked-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-02 16:00:28 +02:00
Pierre Morel e5282de931 s390: ap: kvm: add PQAP interception for AQIC
We prepare the interception of the PQAP/AQIC instruction for
the case the AQIC facility is enabled in the guest.

First of all we do not want to change existing behavior when
intercepting AP instructions without the SIE allowing the guest
to use AP instructions.

In this patch we only handle the AQIC interception allowed by
facility 65 which will be enabled when the complete interception
infrastructure will be present.

We add a callback inside the KVM arch structure for s390 for
a VFIO driver to handle a specific response to the PQAP
instruction with the AQIC command and only this command.

But we want to be able to return a correct answer to the guest
even there is no VFIO AP driver in the kernel.
Therefor, we inject the correct exceptions from inside KVM for the
case the callback is not initialized, which happens when the vfio_ap
driver is not loaded.

We do consider the responsibility of the driver to always initialize
the PQAP callback if it defines queues by initializing the CRYCB for
a guest.
If the callback has been setup we call it.
If not we setup an answer considering that no queue is available
for the guest when no callback has been setup.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Acked-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-02 16:00:27 +02:00
Julian Wiedmann ac6639cd3d s390/qdio: don't touch the dsci in tiqdio_add_input_queues()
Current code sets the dsci to 0x00000080. Which doesn't make any sense,
as the indicator area is located in the _left-most_ byte.

Worse: if the dsci is the _shared_ indicator, this potentially clears
the indication of activity for a _different_ device.
tiqdio_thinint_handler() will then have no reason to call that device's
IRQ handler, and the device ends up stalling.

Fixes: d0c9d4a89f ("[S390] qdio: set correct bit in dsci")
Cc: <stable@vger.kernel.org>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-02 16:00:27 +02:00
Julian Wiedmann e54e4785cb s390/qdio: (re-)initialize tiqdio list entries
When tiqdio_remove_input_queues() removes a queue from the tiq_list as
part of qdio_shutdown(), it doesn't re-initialize the queue's list entry
and the prev/next pointers go stale.

If a subsequent qdio_establish() fails while sending the ESTABLISH cmd,
it calls qdio_shutdown() again in QDIO_IRQ_STATE_ERR state and
tiqdio_remove_input_queues() will attempt to remove the queue entry a
second time. This dereferences the stale pointers, and bad things ensue.
Fix this by re-initializing the list entry after removing it from the
list.

For good practice also initialize the list entry when the queue is first
allocated, and remove the quirky checks that papered over this omission.
Note that prior to
commit e521813468 ("s390/qdio: fix access to uninitialized qdio_q fields"),
these checks were bogus anyway.

setup_queues_misc() clears the whole queue struct, and thus needs to
re-init the prev/next pointers as well.

Fixes: 779e6e1c72 ("[S390] qdio: new qdio driver.")
Cc: <stable@vger.kernel.org>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-02 16:00:27 +02:00
Dan Carpenter 83eb1a4150 s390/dasd: Fix a precision vs width bug in dasd_feature_list()
The "len" variable is the length of the option up to the next option or
to the end of the string which ever first.  We want to print the invalid
option so we want precision "%.*s" but the format is width "%*s" so it
prints up to the end of the string.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Tested-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-02 16:00:26 +02:00
Cornelia Huck ebc3d17915 s390/cio: introduce driver_override on the css bus
Sometimes, we want to control which of the matching drivers
binds to a subchannel device (e.g. for subchannels we want to
handle via vfio-ccw).

For pci devices, a mechanism to do so has been introduced in
782a985d7a ("PCI: Introduce new device binding path using
pci_dev.driver_override"). It makes sense to introduce the
driver_override attribute for subchannel devices as well, so
that we can easily extend the 'driverctl' tool (which makes
use of the driver_override attribute for pci).

Note that unlike pci we still require a driver override to
match the subchannel type; matching more than one subchannel
type is probably not useful anyway.

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-02 16:00:26 +02:00
Julian Wiedmann eca1d5c22d s390/qeth: move cast type selection into fill_header()
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:24 -07:00
Julian Wiedmann 980f4568fa s390/qeth: extract helper for route validation
As follow-up to commit 0cd6783d3c ("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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:24 -07:00
Julian Wiedmann c097cc9228 s390/qeth: consolidate skb RX processing in L3 driver
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:24 -07:00
Julian Wiedmann c4733c32ca s390/qeth: consolidate pm code
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:24 -07:00
Julian Wiedmann d4c08afafa s390/qeth: streamline SNMP cmd code
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann c3b2218d31 s390/qeth: remove static cmd buffer infrastructure
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann f19f8fd2df s390/qeth: dynamically allocate MPC cmds
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann 2cfb4810a3 s390/qeth: dynamically allocate vnicc cmds
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: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann 5cfbe10a00 s390/qeth: dynamically allocate diag cmds
Add a new wrapper that allocates DIAG cmds of the right size, and fills
in the common fields.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann b9150461e5 s390/qeth: dynamically allocate various cmds with sub-types
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann 1c696c896f s390/qeth: clarify parameter for simple assist cmds
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann a59d121da2 s390/qeth: dynamically allocate simple IPA cmds
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Cornelia Huck dbd66558dd vfio-ccw: make convert_ccw0_to_ccw1 static
Reported by sparse.

Fixes: 7f8e89a8f2 ("vfio-ccw: Factor out the ccw0-to-ccw1 transition")
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190624090721.16241-1-cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-06-24 17:05:16 +02:00
Vasily Gorbik 9de3191249 Refactoring of the vfio-ccw cp handling, simplifying the
code and avoiding unneeded allocating/copying.
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Merge tag 'vfio-ccw-20190621' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw into features

Refactoring of the vfio-ccw cp handling, simplifying the
code and avoiding unneeded allocating/copying.

* tag 'vfio-ccw-20190621' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw:
  vfio-ccw: Remove copy_ccw_from_iova()
  vfio-ccw: Factor out the ccw0-to-ccw1 transition
  vfio-ccw: Copy CCW data outside length calculation
  vfio-ccw: Skip second copy of guest cp to host
  vfio-ccw: Move guest_cp storage into common struct
  s390/cio: Combine direct and indirect CCW paths
  vfio-ccw: Rearrange IDAL allocation in direct CCW
  vfio-ccw: Remove pfn_array_table
  vfio-ccw: Adjust the first IDAW outside of the nested loops
  vfio-ccw: Rearrange pfn_array and pfn_array_table arrays
  s390/cio: Use generalized CCW handler in cp_init()
  s390/cio: Generalize the TIC handler
  s390/cio: Refactor the routine that handles TIC CCWs
  s390/cio: Squash cp_free() and cp_unpin_free()

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-06-24 17:02:28 +02:00
David S. Miller 92ad6325cb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor SPDX change conflict.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-22 08:59:24 -04:00
Eric Farman 5223bee837 vfio-ccw: Remove copy_ccw_from_iova()
Just to keep things tidy.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20190618202352.39702-6-farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-21 14:13:37 +02:00
Eric Farman 7f8e89a8f2 vfio-ccw: Factor out the ccw0-to-ccw1 transition
This is a really useful function, but it's buried in the
copy_ccw_from_iova() routine so that ccwchain_calc_length()
can just work with Format-1 CCWs while doing its counting.
But it means we're translating a full 2K of "CCWs" to Format-1,
when in reality there's probably far fewer in that space.

Let's factor it out, so maybe we can do something with it later.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20190618202352.39702-5-farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-21 14:13:11 +02:00
Eric Farman ded563f31d vfio-ccw: Copy CCW data outside length calculation
It doesn't make much sense to "hide" the copy to the channel_program
struct inside a routine that calculates the length of the chain.

Let's move it to the calling routine, which will later copy from
channel_program to the memory it allocated itself.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20190618202352.39702-4-farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-21 14:12:45 +02:00
Eric Farman 6246590230 vfio-ccw: Skip second copy of guest cp to host
We already pinned/copied/unpinned 2K (256 CCWs) of guest memory
to the host space anchored off vfio_ccw_private.  There's no need
to do that again once we have the length calculated, when we could
just copy the section we need to the "permanent" space for the I/O.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20190618202352.39702-3-farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-21 14:12:29 +02:00
Eric Farman 1d897e478d vfio-ccw: Move guest_cp storage into common struct
Rather than allocating/freeing a piece of memory every time
we try to figure out how long a CCW chain is, let's use a piece
of memory allocated for each device.

The io_mutex added with commit 4f76617378 ("vfio-ccw: protect
the I/O region") is held for the duration of the VFIO_CCW_EVENT_IO_REQ
event that accesses/uses this space, so there should be no race
concerns with another CPU attempting an (unexpected) SSCH for the
same device.

Suggested-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20190618202352.39702-2-farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-21 14:12:19 +02:00
Julian Wiedmann 96e5aaf914 s390/cio: move struct node_descriptor to cio.h
This allows device drivers (eg. qeth) to use the struct when processing
information retrieved via RCD.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-06-19 17:54:27 +02:00
Heiko Carstens 191fa92b34 s390/sclp: remove call home support
This feature has never been used, so remove it.

Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-06-19 17:54:27 +02:00
Eric Farman 01aa26c672 s390/cio: Combine direct and indirect CCW paths
With both the direct-addressed and indirect-addressed CCW paths
simplified to this point, the amount of shared code between them is
(hopefully) more easily visible.  Move the processing of IDA-specific
bits into the direct-addressed path, and add some useful commentary of
what the individual pieces are doing.  This allows us to remove the
entire ccwchain_fetch_idal() routine and maintain a single function
for any non-TIC CCW.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-10-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:31:41 +02:00
Eric Farman e8573b39a8 vfio-ccw: Rearrange IDAL allocation in direct CCW
This is purely deck furniture, to help understand the merge of the
direct and indirect handlers.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-9-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:31:17 +02:00
Eric Farman e7eaf91b0a vfio-ccw: Remove pfn_array_table
Now that both CCW codepaths build this nested array:

  ccwchain->pfn_array_table[1]->pfn_array[#idaws/#pages]

We can collapse this into simply:

  ccwchain->pfn_array[#idaws/#pages]

Let's do that, so that we don't have to continually navigate two
nested arrays when the first array always has a count of one.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-8-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:30:46 +02:00
Eric Farman 8aabf0edae vfio-ccw: Adjust the first IDAW outside of the nested loops
Now that pfn_array_table[] is always an array of 1, it seems silly to
check for the very first entry in an array in the middle of two nested
loops, since we know it'll only ever happen once.

Let's move this outside the loops to simplify things, even though
the "k" variable is still necessary.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-7-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:30:25 +02:00
Eric Farman cc06ee983c vfio-ccw: Rearrange pfn_array and pfn_array_table arrays
While processing a channel program, we currently have two nested
arrays that carry a slightly different structure.  The direct CCW
path creates this:

  ccwchain->pfn_array_table[1]->pfn_array[#pages]

while an IDA CCW creates:

  ccwchain->pfn_array_table[#idaws]->pfn_array[1]

The distinction appears to state that each pfn_array_table entry
points to an array of contiguous pages, represented by a pfn_array,
um, array.  Since the direct-addressed scenario can ONLY represent
contiguous pages, it makes the intermediate array necessary but
difficult to recognize.  Meanwhile, since an IDAL can contain
non-contiguous pages and there is no logic in vfio-ccw to detect
adjacent IDAWs, it is the second array that is necessary but appearing
to be superfluous.

I am not aware of any documentation that states the pfn_array[] needs
to be of contiguous pages; it is just what the code does today.
I don't see any reason for this either, let's just flip the IDA
codepath around so that it generates:

  ch_pat->pfn_array_table[1]->pfn_array[#idaws]

This will bring it in line with the direct-addressed codepath,
so that we can understand the behavior of this memory regardless
of what type of CCW is being processed.  And it means the casual
observer does not need to know/care whether the pfn_array[]
represents contiguous pages or not.

NB: The existing vfio-ccw code only supports 4K-block Format-2 IDAs,
so that "#pages" == "#idaws" in this area.  This means that we will
have difficulty with this overlap in terminology if support for
Format-1 or 2K-block Format-2 IDAs is ever added.  I don't think that
this patch changes our ability to make that distinction.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-6-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:30:00 +02:00
Eric Farman 99afcb05d9 s390/cio: Use generalized CCW handler in cp_init()
It is now pretty apparent that ccwchain_handle_ccw()
(nee ccwchain_handle_tic()) does everything that cp_init()
wants to do.

Let's remove that duplicated code from cp_init() and let
ccwchain_handle_ccw() handle it itself.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-5-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:29:33 +02:00
Eric Farman 363fe5f7ae s390/cio: Generalize the TIC handler
Refactor ccwchain_handle_tic() into a routine that handles a channel
program address (which itself is a CCW pointer), rather than a CCW pointer
that is only a TIC CCW.  This will make it easier to reuse this code for
other CCW commands.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-4-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:29:10 +02:00
Eric Farman e64bd68946 s390/cio: Refactor the routine that handles TIC CCWs
Extract the "does the target of this TIC already exist?" check from
ccwchain_handle_tic(), so that it's easier to refactor that function
into one that cp_init() is able to use.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-3-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:28:50 +02:00
Eric Farman 812271b910 s390/cio: Squash cp_free() and cp_unpin_free()
The routine cp_free() does nothing but call cp_unpin_free(), and while
most places call cp_free() there is one caller of cp_unpin_free() used
when the cp is guaranteed to have not been marked initialized.

This seems like a dubious way to make a distinction, so let's combine
these routines and make cp_free() do all the work.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-2-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:28:29 +02:00
Halil Pasic 39c7dcb158 virtio/s390: make airq summary indicators DMA
The hypervisor needs to interact with the summary indicators, so these
need to be DMA memory as well (at least for protected virtualization
guests).

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:41 +02:00
Halil Pasic 48720ba568 virtio/s390: use DMA memory for ccw I/O and classic notifiers
Before virtio-ccw could get away with not using DMA API for the pieces of
memory it does ccw I/O with. With protected virtualization this has to
change, since the hypervisor needs to read and sometimes also write these
pieces of memory.

The hypervisor is supposed to poke the classic notifiers, if these are
used, out of band with regards to ccw I/O. So these need to be allocated
as DMA memory (which is shared memory for protected virtualization
guests).

Let us factor out everything from struct virtio_ccw_device that needs to
be DMA memory in a satellite that is allocated as such.

Note: The control blocks of I/O instructions do not need to be shared.
These are marshalled by the ultravisor.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:37 +02:00
Halil Pasic 22a4a639b9 virtio/s390: add indirection to indicators access
This will come in handy soon when we pull out the indicators from
virtio_ccw_device to a memory area that is shared with the hypervisor
(in particular for protected virtualization guests).

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:33 +02:00
Halil Pasic 01b3fb1ea0 virtio/s390: use cacheline aligned airq bit vectors
The flag AIRQ_IV_CACHELINE was recently added to airq_iv_create(). Let
us use it! We actually wanted the vector to span a cacheline all along.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:28 +02:00
Halil Pasic b50623e5db s390/airq: use DMA memory for adapter interrupts
Protected virtualization guests have to use shared pages for airq
notifier bit vectors, because the hypervisor needs to write these bits.

Let us make sure we allocate DMA memory for the notifier bit vectors by
replacing the kmem_cache with a dma_cache and kalloc() with
cio_dma_zalloc().

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:05 +02:00
Halil Pasic 37db8985b2 s390/cio: add basic protected virtualization support
As virtio-ccw devices are channel devices, we need to use the
dma area within the common I/O layer for any communication with
the hypervisor.

Note that we do not need to use that area for control blocks
directly referenced by instructions, e.g. the orb.

It handles neither QDIO in the common code, nor any device type specific
stuff (like channel programs constructed by the DASD driver).

An interesting side effect is that virtio structures are now going to
get allocated in 31 bit addressable storage.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:00 +02:00
Halil Pasic bb99332a2b s390/cio: introduce DMA pools to cio
To support protected virtualization cio will need to make sure the
memory used for communication with the hypervisor is DMA memory.

Let us introduce one global pool for cio.

Our DMA pools are implemented as a gen_pool backed with DMA pages. The
idea is to avoid each allocation effectively wasting a page, as we
typically allocate much less than PAGE_SIZE.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:24:56 +02:00
David Hildenbrand 58443b676b s390/pkey: Use -ENODEV instead of -EOPNOTSUPP
systemd-modules-load.service automatically tries to load the pkey module
on systems that have MSA.

Pkey also requires the MSA3 facility and a bunch of subfunctions.
Failing with -EOPNOTSUPP makes "systemd-modules-load.service" fail on
any system that does not have all needed subfunctions. For example,
when running under QEMU TCG (but also on systems where protected keys
are disabled via the HMC).

Let's use -ENODEV, so systemd-modules-load.service properly ignores
failing to load the pkey module because of missing HW functionality.

While at it, also convert the -EOPNOTSUPP in pkey_clr2protkey() to -ENODEV.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:24:36 +02:00
Julian Wiedmann d9b9f40bba s390/qeth: allocate a single cmd on read channel
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: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:39:32 -07:00