Upcoming new SCMI transports won't need any kind of shared memory support.
Compile shmem.c only if a shmem based transport is selected.

Link: https://lore.kernel.org/r/20210803131024.40280-10-cristian.marussi@arm.comCo-developed-by: NPeter Hilber <peter.hilber@opensynergy.com>
Signed-off-by: NIgor Skalkin <igor.skalkin@opensynergy.com>
[ Peter: Adapted patch for submission to upstream. ]
Signed-off-by: NPeter Hilber <peter.hilber@opensynergy.com>
[ Cristian: Adapted patch/commit_msg to new SCMI Kconfig layout ]
Signed-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

Add configuration options to be able to select which SCMI transports have
to be compiled into the SCMI stack.

Mailbox and SMC are by default enabled if their related dependencies are
satisfied.

While doing that move all SCMI related config options in their own
dedicated submenu.

Link: https://lore.kernel.org/r/20210803131024.40280-9-cristian.marussi@arm.comSigned-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

Add a check for the presence of .poll_done transport operation so that
transports that do not need to support polling mode have no need to provide
a dummy .poll_done callback either and polling mode can be disabled in the
SCMI core for that tranport.

Link: https://lore.kernel.org/r/20210803131024.40280-8-cristian.marussi@arm.comSigned-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

Make transport operation .clear_channel optional since some transports
do not need it and so avoid to have them implement dummy callbacks.

Link: https://lore.kernel.org/r/20210803131024.40280-7-cristian.marussi@arm.comSigned-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

Even though in case of asynchronous commands an SCMI platform is
constrained to emit the delayed response message only after the related
message response has been sent, the configured underlying transport could
still deliver such messages together or in inverted order, causing races
due to the concurrent or out-of-order access to the underlying xfer.

Introduce a mechanism to grant exclusive access to an xfer in order to
properly serialize concurrent accesses to the same xfer originating from
multiple correlated messages.

Add additional state information to xfer descriptors so as to be able to
identify out-of-order message deliveries and act accordingly:

 - when a delayed response is expected but delivered before the related
   response, the synchronous response is considered as successfully
   received and the delayed response processing is carried on as usual.

 - when/if the missing synchronous response is subsequently received, it
   is discarded as not congruent with the current state of the xfer, or
   simply, because the xfer has been already released and so, now, the
   monotonically increasing sequence number carried by the late response
   is stale.

Link: https://lore.kernel.org/r/20210803131024.40280-6-cristian.marussi@arm.comSigned-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

Tokens are sequence numbers embedded in the each SCMI message header: they
are used to correlate commands with responses (and delayed responses), but
their usage and policy of selection is entirely up to the caller (usually
the OSPM agent), while they are completely opaque to the callee (i.e. SCMI
platform) which merely copies them back from the command into the response
message header.
This also means that the platform does not, can not and should not enforce
any kind of policy on received messages depending on the contained sequence
number: platform can perfectly handle concurrent requests carrying the same
identifiying token if that should happen.

Moreover the platform is not required to produce in-order responses to
agent requests, the only constraint in these regards is that in case of
an asynchronous message the delayed response must be sent after the
immediate response for the synchronous part of the command transaction.

Currenly the SCMI stack of the OSPM agent selects a token for the egressing
commands picking the lowest possible number which is not already in use by
an existing in-flight transaction, which means, in other words, that we
immediately reuse any token after its transaction has completed or it has
timed out: this policy indeed does simplify management and lookup of tokens
and associated xfers.

Under the above assumptions and constraints, since there is really no state
shared between the agent and the platform to let the platform know when a
token and its associated message has timed out, the current policy of early
reuse of tokens can easily lead to the situation in which a spurious or
late received response (or delayed_response), related to an old stale and
timed out transaction, can be wrongly associated to a newer valid in-flight
xfer that just happens to have reused the same token.

This misbehaviour on such late/spurious responses is more easily exposed on
those transports that naturally have an higher level of parallelism in
processing multiple concurrent in-flight messages.

This commit introduces a new policy of selection of tokens for the OSPM
agent: each new command transfer now gets the next available, monotonically
increasing token, until tokens are exhausted and the counter rolls over.

Such new policy mitigates the above issues with late/spurious responses
since the tokens are now reused as late as possible (when they roll back
ideally) and so it is much easier to identify such late/spurious responses
to stale timed out transactions: this also helps in simplifying the
specific transports implementation since stale transport messages can be
easily identified and discarded early on in the rx path without the need
to cross check their actual state with the core transport layer.
This mitigation is even more effective when, as is usually the case, the
maximum number of pending messages is capped by the platform to a much
lower number than the whole possible range of tokens values (2^10).

This internal policy change in the core SCMI transport layer is fully
transparent to the specific transports so it has not and should not have
any impact on the transports implementation.

Link: https://lore.kernel.org/r/20210803131024.40280-5-cristian.marussi@arm.comSigned-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

Some SCMI transport could need to perform some transport specific setup
before they can be used by the SCMI core transport layer: typically this
early setup consists in registering with some other kernel subsystem.

Add the optional capability for a transport to provide a couple of init
and exit functions that are assured to be called early during the SCMI
core initialization phase, well before the SCMI core probing step.

[ Peter: Adapted RFC patch by Cristian for submission to upstream. ]

Link: https://lore.kernel.org/r/20210803131024.40280-4-cristian.marussi@arm.comSigned-off-by: NPeter Hilber <peter.hilber@opensynergy.com>
[ Cristian: Fixed scmi_transports_exit point of invocation ]
Signed-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

Being a while that we have SCMI trace events in the SCMI stack, remove
this debug helper and its call sites.

Link: https://lore.kernel.org/r/20210803131024.40280-3-cristian.marussi@arm.comSigned-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

Add SCMI type handling to pack/unpack_scmi_header common helper functions.
Initialize hdr.type properly when initializing a command xfer.

Link: https://lore.kernel.org/r/20210803131024.40280-2-cristian.marussi@arm.comSigned-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

SCMI message headers carry a sequence number and such field is sized to
allow for MSG_TOKEN_MAX distinct numbers; moreover zero is not really an
acceptable maximum number of pending in-flight messages.

Fix accordingly the checks performed on the value exported by transports
in scmi_desc.max_msg

Link: https://lore.kernel.org/r/20210712141833.6628-3-cristian.marussi@arm.comReported-by: NVincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: NCristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: updated the patch title and error message]
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

scmi_resp_sensor_reading_complete structure is meant to represent an
SCMI asynchronous reading complete message. The readings field with
a 64bit type forces padding and breaks reads in scmi_sensor_reading_get.

Split it in two adjacent 32bit readings_low/high subfields to avoid the
padding within the structure. Alternatively we could to mark the structure
packed.

Link: https://lore.kernel.org/r/20210628170042.34105-1-cristian.marussi@arm.com
Fixes: e2083d36 ("firmware: arm_scmi: Add SCMI v3.0 sensors timestamped reads")
Signed-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

Kernel doc validation script still complains about the following:

|No description found for return value of 'scmi_get_protocol_device'
|No description found for return value of 'scmi_devm_notifier_register'
|No description found for return value of 'scmi_devm_notifier_unregister'

Fix adding missing Return kernel-doc statements.

Link: https://lore.kernel.org/r/20210712143504.33541-1-cristian.marussi@arm.comSigned-off-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

The scmi_linux_errmap buffer access index is supposed to depend on the
array size to prevent element out of bounds access. It uses SCMI_ERR_MAX
to check bounds but that can mismatch with the array size. It also
changes the success into -EIO though scmi_linux_errmap is never used in
case of success, it is expected to work for success case too.

It is slightly confusing code as the negative of the error code
is used as index to the buffer. Fix it by negating it at the start and
make it more readable.

Link: https://lore.kernel.org/r/20210707135028.1869642-1-sudeep.holla@arm.comReported-by: Nkernel test robot <lkp@intel.com>
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

The bus probe callback calls the driver callback without further
checking. Better be safe than sorry and refuse registration of a driver
without a probe function to prevent a NULL pointer exception.

Link: https://lore.kernel.org/r/20210624095059.4010157-2-sudeep.holla@arm.com
Fixes: 933c5044 ("firmware: arm_scmi: add scmi protocol bus to enumerate protocol devices")
Reported-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: NCristian Marussi <cristian.marussi@arm.com>
Reviewed-by: NCristian Marussi <cristian.marussi@arm.com>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

When the driver core calls the probe callback it already checked that
the devices match, so there is no need to call the match callback again.

Link: https://lore.kernel.org/r/20210624095059.4010157-1-sudeep.holla@arm.comSuggested-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: NCristian Marussi <cristian.marussi@arm.com>
Reviewed-by: NCristian Marussi <cristian.marussi@arm.com>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

arch/arm/mach-ixp4xx/include/mach/platform.h now gets included indirectly
and defines REG_OFFSET. Rename the register and bit definition to something
specific to the driver.

Fixes: 7fd70c65 ("ARM: irqstat: Get rid of duplicated declaration")
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210710211431.1393589-1-alexandre.belloni@bootlin.com

commit 03623b4b ("rtc: pcf2127: add tamper detection support")
added support for timestamp interrupts. However they are not being
handled in the irq handler. If a timestamp interrupt occurs it
results in kernel disabling the interrupt and displaying the call
trace:

[  121.145580] irq 78: nobody cared (try booting with the "irqpoll" option)
...
[  121.238087] [<00000000c4d69393>] irq_default_primary_handler threaded [<000000000a90d25b>] pcf2127_rtc_irq [rtc_pcf2127]
[  121.248971] Disabling IRQ #78

Handle timestamp interrupts in pcf2127_rtc_irq(). Save time stamp
before clearing TSF1 and TSF2 flags so that it can't be overwritten.
Set a flag to mark if the timestamp is valid and only report to sysfs
if the flag is set. To mimic the hardware behavior, don’t save
another timestamp until the first one has been read by the userspace.

However, if the alarm irq is not configured, keep the old way of
handling timestamp interrupt in the timestamp0 sysfs calls.
Signed-off-by: NMian Yousaf Kaukab <ykaukab@suse.de>
Reviewed-by: NBruno Thomsen <bruno.thomsen@gmail.com>
Tested-by: NBruno Thomsen <bruno.thomsen@gmail.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210629150643.31551-1-ykaukab@suse.de

The offset variable is checked by at91_rtc_readalarm(), but this check
is unnecessary because the previous check knew that the value of this
variable was not 0.
This removes that unnecessary offset variable checks.

Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Acked-by: NNicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210708051340.341345-1-nobuhiro1.iwamatsu@toshiba.co.jp

s5m_check_peding_alarm_interrupt() in s5m_rtc_read_alarm() gets the return
value, but doesn't use it.
This modifies using the s5m_check_peding_alarm_interrupt()"s return value
as the s5m_rtc_read_alarm()'s return value.

Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: linux-samsung-soc@vger.kernel.org
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Reviewed-by: NKrzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210708051304.341278-1-nobuhiro1.iwamatsu@toshiba.co.jp

Use SPDX-License-Identifier instead of a verbose license text.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210707075804.337458-11-nobuhiro1.iwamatsu@toshiba.co.jp

Use SPDX-License-Identifier instead of a verbose license text.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210707075804.337458-9-nobuhiro1.iwamatsu@toshiba.co.jp

Use SPDX-License-Identifier instead of a verbose license text.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210707075804.337458-8-nobuhiro1.iwamatsu@toshiba.co.jp

For C files, use the C99 format (//).
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210707075804.337458-7-nobuhiro1.iwamatsu@toshiba.co.jp

For C files, use the C99 format (//).

Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Baolin Wang <baolin.wang7@gmail.com>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210707075804.337458-6-nobuhiro1.iwamatsu@toshiba.co.jp

Use SPDX-License-Identifier instead of a verbose license text.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210707075804.337458-5-nobuhiro1.iwamatsu@toshiba.co.jp

Use SPDX-License-Identifier instead of a verbose license text.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210707075804.337458-4-nobuhiro1.iwamatsu@toshiba.co.jp

Use SPDX-License-Identifier instead of a verbose license text.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210707075804.337458-3-nobuhiro1.iwamatsu@toshiba.co.jp

Use SPDX-License-Identifier instead of a verbose license text.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210707075804.337458-2-nobuhiro1.iwamatsu@toshiba.co.jp

This reverts commit 65db0405.

Guenter reported that after 65db0405, the ppc:sam460ex qemu emulation
no longer boots from nvme:

  nvme nvme0: Device not ready; aborting initialisation, CSTS=0x0
  nvme nvme0: Removing after probe failure status: -19

Link: https://lore.kernel.org/r/20210709231529.GA3270116@roeck-us.netReported-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

After updating the datasheet URL, the PCF85063A  datasheet revision
has changed.

Adjust it accordingly.
Reported-by: NNobuhiro Iwamatsu <iwamatsu@nigauri.org>
Signed-off-by: NFabio Estevam <festevam@gmail.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210624120953.2313378-1-festevam@gmail.com

Since d4a45c68 ("irqdomain: Protect the linear revmap with RCU"),
any irqdomain lookup requires the RCU read lock to be held.

This assumes that the architecture code will be structured such as
irq_enter() will be called *before* the interrupt is looked up
in the irq domain. However, this isn't the case for MIPS, and a number
of drivers are structured to do it the other way around when handling
an interrupt in their root irqchip (secondary irqchips are OK by
construction).

This results in a RCU splat on a lockdep-enabled kernel when the kernel
takes an interrupt from idle, as reported by Guenter Roeck.

Note that this could have fired previously if any driver had used
tree-based irqdomain, which always had the RCU requirement.

To solve this, provide a MIPS-specific helper (do_domain_IRQ())
as the pendent of do_IRQ() that will do thing in the right order
(and maybe save some cycles in the process).

Ideally, MIPS would be moved over to using handle_domain_irq(),
but that's much more ambitious.
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Tested-by: NGuenter Roeck <linux@roeck-us.net>
[maz: add dependency on CONFIG_IRQ_DOMAIN after report from the kernelci bot]
Signed-off-by: NMarc Zyngier <maz@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20210705172352.GA56304@roeck-us.net
Link: https://lore.kernel.org/r/20210706110647.3979002-1-maz@kernel.org

Rework of the ap_dqap() inline function with the dqap inline assembler
invocation and the caller code in ap_queue.c to be able to handle
replies which exceed the receive buffer size.

ap_dqap() now provides two additional parameters to handle together
with the caller the case where a reply in the firmware queue entry
exceeds the given message buffer size. It depends on the caller how to
exactly handle this. The behavior implemented now by ap_sm_recv() in
ap_queue.c is to simple purge this entry from the firmware queue and
let the caller 'receive' a -EMSGSIZE for the request without
delivering any reply data - not even a truncated reply message.

However, the reworked ap_dqap() could now get invoked in a way that
the message is received in multiple parts and the caller assembles the
parts into one reply message.
Signed-off-by: NHarald Freudenberger <freude@linux.ibm.com>
Suggested-by: NJuergen Christ <jchrist@linux.ibm.com>
Reviewed-by: NJuergen Christ <jchrist@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Let's handle unplug in Big Block Mode similar to Sub Block Mode --
prioritize memory blocks onlined to ZONE_MOVABLE.

We won't care further about big blocks with mixed zones, as it's
rather a corner case that won't matter in practice.
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-8-david@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>

Let's simplify high-level big block selection when unplugging in
Big Block Mode.

Combine handling of offline and online blocks. We can get rid of
virtio_mem_bbm_bb_is_offline() and simply use
virtio_mem_bbm_offline_remove_and_unplug_bb(), as that already tolerates
offline parts.

We can race with concurrent onlining/offlining either way, so we don;t
have to be super correct by failing if an offline big block we'd like to
unplug just got (partially) onlined.
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-7-david@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>

Until now, memory provided by a single virtio-mem device was usually
either onlined completely to ZONE_MOVABLE (online_movable) or to
ZONE_NORMAL (online_kernel); however, that will change in the future.

There are two reasons why we want to track to which zone a memory blocks
belongs to and prioritize ZONE_MOVABLE blocks:

1) Memory managed by ZONE_MOVABLE can more likely get unplugged, therefore,
   resulting in a faster memory hotunplug process. Further, we can more
   reliably unplug and remove complete memory blocks, removing metadata
   allocated for the whole memory block.

2) We want to avoid corner cases where unplugging with the current scheme
   (highest to lowest address) could result in accidential zone imbalances,
   whereby we remove too much ZONE_NORMAL memory for ZONE_MOVABLE memory
   of the same device.

Let's track the zone via memory block states and try unplug from
ZONE_MOVABLE first. Rename VIRTIO_MEM_SBM_MB_ONLINE* to
VIRTIO_MEM_SBM_MB_KERNEL* to avoid even longer state names.

In commit 27f85279 ("virtio-mem: don't special-case ZONE_MOVABLE"),
we removed slightly similar tracking for fully plugged memory blocks to
support unplugging from ZONE_MOVABLE at all -- as we didn't allow partially
plugged memory blocks in ZONE_MOVABLE before that. That commit already
mentioned "In the future, we might want to remember the zone again and use
the information when (un)plugging memory."
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-6-david@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>

Let's simplify by introducing a new virtio_mem_sbm_unplug_any_sb(),
similar to virtio_mem_sbm_plug_any_sb(), to simplify high-level memory
block selection when unplugging in Sub Block Mode.

Rename existing virtio_mem_sbm_unplug_any_sb() to
virtio_mem_sbm_unplug_any_sb_raw().

The only change is that we now temporarily unlock the hotplug mutex around
cond_resched() when processing offline memory blocks, which doesn't
make a real difference as we already have to temporarily unlock in
virtio_mem_sbm_unplug_any_sb_offline() when removing a memory block.
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-5-david@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>

Let's simplify high-level memory block selection when plugging in Sub
Block Mode.

No need for two separate loops when selecting memory blocks for plugging
memory. Avoid passing the "online" state by simply obtaining the state
in virtio_mem_sbm_plug_any_sb().
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-4-david@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>

Let's use page_zonenum() instead of zone_idx(page_zone()).
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-3-david@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>

We are reading a Big Block Mode value while in Sub Block Mode
when initializing. Fortunately, vm->bbm.bb_size maps to some counter
in the vm->sbm.mb_count array, which is 0 at that point in time.

No harm done; still, this was unintended and is not future-proof.

Fixes: 4ba50cd3 ("virtio-mem: Big Block Mode (BBM) memory hotplug")
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-2-david@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>

Clear the available index as part of the initialization process to
clear and values that might be left from previous usage of the device.
For example, if the device was previously used by vhost_vdpa and now
probed by vhost_vdpa, you want to start with indices.

Fixes: c043b4a8 ("virtio: introduce a vDPA based transport")
Signed-off-by: NEli Cohen <elic@nvidia.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210602021536.39525-5-jasowang@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NEli Cohen <elic@nvidia.com>