The flags that should be or-ed into the watchdog_info.options by drivers
all start with WDIOF_, e.g. WDIOF_SETTIMEOUT, which indicates that the
driver's watchdog_ops has a usable set_timeout.
WDIOC_SETTIMEOUT was used instead, which expands to 0xc0045706, which
equals:
WDIOF_FANFAULT | WDIOF_EXTERN1 | WDIOF_PRETIMEOUT | WDIOF_ALARMONLY |
WDIOF_MAGICCLOSE | 0xc0045000
These were so far indicated to userspace on WDIOC_GETSUPPORT.
As the driver has not yet been migrated to the new watchdog kernel API,
the constant can just be dropped without substitute.
Fixes: 96cb4eb019 ("watchdog: f71808e_wdt: new watchdog driver for Fintek F71808E and F71882FG")
Cc: stable@vger.kernel.org
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200611191750.28096-4-a.fatoum@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
The FIXME comment has been in-tree since the very first git commit.
The described behavior has been since relied on by some userspace, e.g.
the util-linux wdctl command and has been ignored by some kernelspace,
like the f71808e_wdt driver.
The functionality is useful to have to be able to differentiate between a
driver that doesn't support WDIOF_CARDRESET and one that does, but hasn't
had a watchdog reset, thus drop the FIXME to encourage drivers adopting
this convention.
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200611191750.28096-2-a.fatoum@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
DW Watchdog can rise an interrupt in case if IRQ request mode is enabled
and timer reaches the zero value. In this case the IRQ lane is left
pending until either the next watchdog kick event (watchdog restart) or
until the WDT_EOI register is read or the device/system reset. This
interface can be used to implement the pre-timeout functionality
optionally provided by the Linux kernel watchdog devices.
IRQ mode provides a two stages timeout interface. It means the IRQ is
raised when the counter reaches zero, while the system reset occurs only
after subsequent timeout if the timer restart is not performed. Due to
this peculiarity the pre-timeout value is actually set to the achieved
hardware timeout, while the real watchdog timeout is considered to be
twice as much of it. This applies a significant limitation on the
pre-timeout values, so current implementation supports either zero value,
which disables the pre-timeout events, or non-zero values, which imply
the pre-timeout to be at least half of the current watchdog timeout.
Note that we ask the interrupt controller to detect the rising-edge
pre-timeout interrupts to prevent the high-level-IRQs flood, since
if the pre-timeout happens, the IRQ lane will be left pending until
it's cleared by the timer restart.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200530073557.22661-7-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
In case if the DW Watchdog IP core is synthesised with
WDT_USE_FIX_TOP == false, the TOP interval indexes make the device
to load a custom periods to the counter. These periods are hardwired
at the IP synthesis stage and can be within [2^8, 2^(WDT_CNT_WIDTH - 1)].
Alas their values can't be detected at runtime and must be somehow
supplied to the driver so one could properly determine the watchdog
timeout intervals. For this purpose we suggest to have a vendor-
specific dts property "snps,watchdog-tops" utilized, which would
provide an array of sixteen counter values. At device probe stage they
will be used to initialize the watchdog device timeouts determined
from the array values and current clocks source rate.
In order to have custom TOP values supported the driver must be
altered in the following way. First of all the fixed-top values
ready-to-use array must be determined for compatibility with currently
supported devices, which were synthesised with WDT_USE_FIX_TOP == true.
It will be used if either fixed TOP feature is detected being enabled or
no custom TOPs are fetched from the device dt node. Secondly at the probe
stage we must initialize an array of the watchdog timeouts corresponding
to the detected TOPs list and the reference clock rate. For generality the
procedure of initialization is designed in a way to support the TOPs array
with no limitations on the items order or value. Finally the watchdog
period search methods should be altered to support the new timeouts data
structure.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200530073557.22661-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This is what the classic fs/direct-io.c implementation and thuse other
file systems use.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The historic requirement for XFS to invalidate cached pages on
direct IO reads has been lost in the twisty pages of history - it was
inherited from Irix, which implemented page cache invalidation on
read as a method of working around problems synchronising page
cache state with uncached IO.
XFS has carried this ever since. In the initial linux ports it was
necessary to get mmap and DIO to play "ok" together and not
immediately corrupt data. This was the state of play until the linux
kernel had infrastructure to track unwritten extents and synchronise
page faults with allocations and unwritten extent conversions
(->page_mkwrite infrastructure). IOws, the page cache invalidation
on DIO read was necessary to prevent trivial data corruptions. This
didn't solve all the problems, though.
There were peformance problems if we didn't invalidate the entire
page cache over the file on read - we couldn't easily determine if
the cached pages were over the range of the IO, and invalidation
required taking a serialising lock (i_mutex) on the inode. This
serialising lock was an issue for XFS, as it was the only exclusive
lock in the direct Io read path.
Hence if there were any cached pages, we'd just invalidate the
entire file in one go so that subsequent IOs didn't need to take the
serialising lock. This was a problem that prevented ranged
invalidation from being particularly useful for avoiding the
remaining coherency issues. This was solved with the conversion of
i_mutex to i_rwsem and the conversion of the XFS inode IO lock to
use i_rwsem. Hence we could now just do ranged invalidation and the
performance problem went away.
However, page cache invalidation was still needed to serialise
sub-page/sub-block zeroing via direct IO against buffered IO because
bufferhead state attached to the cached page could get out of whack
when direct IOs were issued. We've removed bufferheads from the
XFS code, and we don't carry any extent state on the cached pages
anymore, and so this problem has gone away, too.
IOWs, it would appear that we don't have any good reason to be
invalidating the page cache on DIO reads anymore. Hence remove the
invalidation on read because it is unnecessary overhead,
not needed to maintain coherency between mmap/buffered access and
direct IO anymore, and prevents anyone from using direct IO reads
from intentionally invalidating the page cache of a file.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Most session messages contain a feature mask, but the MDS will
routinely send a REJECT message with one that is zero-length.
Commit 0fa8263367 ("ceph: fix endianness bug when handling MDS
session feature bits") fixed the decoding of the feature mask,
but failed to account for the MDS sending a zero-length feature
mask. This causes REJECT message decoding to fail.
Skip trying to decode a feature mask if the word count is zero.
Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/46823
Fixes: 0fa8263367 ("ceph: fix endianness bug when handling MDS session feature bits")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Tested-by: Patrick Donnelly <pdonnell@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This patch introduce a set of functions for setup/unsetup
and update irq offloading respectively by register/unregister
and re-register the irq_bypass_producer.
With these functions, this commit can setup/unsetup
irq offloading through setting DRIVER_OK/!DRIVER_OK, and
update irq offloading through SET_VRING_CALL.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-5-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
vDPA devices has dedicated backed hardware like
passthrough-ed devices. Then it is possible to setup irq
offloading to vCPU for vDPA devices. Thus this patch tries to
manipulated assigned device counters by
kvm_arch_start/end_assignment() in irqbypass manager, so that
assigned devices could be detected in update_pi_irte()
We will increase/decrease the assigned device counter in kvm/x86.
Both vDPA and VFIO would go through this code path.
Only X86 uses these counters and kvm_arch_start/end_assignment(),
so this code path only affect x86 for now.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-3-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Make use of the flex_array_size() helper to calculate the size of a
flexible array member within an enclosing structure.
This helper offers defense-in-depth against potential integer
overflows, while at the same time makes it explicitly clear that
we are dealing with a flexible array member.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200731130956.GA30525@embeddedor
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We used to have a per device feature whitelist to filter out the
unsupported virtio features. But this seems unnecessary since:
- the main idea behind feature whitelist is to block control vq
feature until we finalize the control virtqueue API. But the current
vhost-vDPA uAPI is sufficient to support control virtqueue. For
device that has hardware control virtqueue, the vDPA device driver
can just setup the hardware virtqueue and let userspace to use
hardware virtqueue directly. For device that doesn't have a control
virtqueue, the vDPA device driver need to use e.g vringh to emulate
a software control virtqueue.
- we don't do it in virtio-vDPA driver
So remove this limitation.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200720085043.16485-1-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The loop may exist if vq->broken is true,
virtqueue_get_buf_ctx_packed or virtqueue_get_buf_ctx_split
will return NULL, so virtnet_poll will reschedule napi to
receive packet, it will lead cpu usage(si) to 100%.
call trace as below:
virtnet_poll
virtnet_receive
virtqueue_get_buf_ctx
virtqueue_get_buf_ctx_packed
virtqueue_get_buf_ctx_split
virtqueue_napi_complete
virtqueue_poll //return true
virtqueue_napi_schedule //it will reschedule napi
to fix this, return false if vq is broken in virtqueue_poll.
Signed-off-by: Mao Wenan <wenan.mao@linux.alibaba.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/1596354249-96204-1-git-send-email-wenan.mao@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Speed and duplex config fields depend on VIRTIO_NET_F_SPEED_DUPLEX
which being 63>31 depends on VIRTIO_F_VERSION_1.
Accordingly, use LE accessors for these fields.
Reported-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
All drivers now use virtio_cread/write_le for LE config
space fields. Drop LE option from virtio_cread/write, only leaving
the option to access transitional fields.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
