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2020-09-09Use DECLARE_*CHECKER* macrosEduardo Habkost
Generated using: $ ./scripts/codeconverter/converter.py -i \ --pattern=TypeCheckMacro $(git grep -l '' -- '*.[ch]') Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Message-Id: <20200831210740.126168-12-ehabkost@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Message-Id: <20200831210740.126168-13-ehabkost@redhat.com> Message-Id: <20200831210740.126168-14-ehabkost@redhat.com> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-09Move QOM typedefs and add missing includesEduardo Habkost
Some typedefs and macros are defined after the type check macros. This makes it difficult to automatically replace their definitions with OBJECT_DECLARE_TYPE. Patch generated using: $ ./scripts/codeconverter/converter.py -i \ --pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]') which will split "typdef struct { ... } TypedefName" declarations. Followed by: $ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \ $(git grep -l '' -- '*.[ch]') which will: - move the typedefs and #defines above the type check macros - add missing #include "qom/object.h" lines if necessary Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Message-Id: <20200831210740.126168-9-ehabkost@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Message-Id: <20200831210740.126168-10-ehabkost@redhat.com> Message-Id: <20200831210740.126168-11-ehabkost@redhat.com> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-07-22virtio-balloon: Replace free page hinting references to 'report' with 'hint'Alexander Duyck
Recently a feature named Free Page Reporting was added to the virtio balloon. In order to avoid any confusion we should drop the use of the word 'report' when referring to Free Page Hinting. So what this patch does is go through and replace all instances of 'report' with 'hint" when we are referring to free page hinting. Acked-by: David Hildenbrand <david@redhat.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Message-Id: <20200720175128.21935.93927.stgit@localhost.localdomain> Cc: qemu-stable@nongnu.org Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-09virtio-balloon: Provide an interface for free page reportingAlexander Duyck
Add support for free page reporting. The idea is to function very similar to how the balloon works in that we basically end up madvising the page as not being used. However we don't really need to bother with any deflate type logic since the page will be faulted back into the guest when it is read or written to. This provides a new way of letting the guest proactively report free pages to the hypervisor, so the hypervisor can reuse them. In contrast to inflate/deflate that is triggered via the hypervisor explicitly. Acked-by: David Hildenbrand <david@redhat.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Message-Id: <20200527041407.12700.73735.stgit@localhost.localdomain>
2020-06-09virtio-balloon: Implement support for page poison reporting featureAlexander Duyck
We need to make certain to advertise support for page poison reporting if we want to actually get data on if the guest will be poisoning pages. Add a value for reporting the poison value being used if page poisoning is enabled in the guest. With this we can determine if we will need to skip free page reporting when it is enabled in the future. The value currently has no impact on existing balloon interfaces. In the case of existing balloon interfaces the onus is on the guest driver to reapply whatever poison is in place. When we add free page reporting the poison value is used to determine if we can perform in-place page reporting. The expectation is that a reported page will already contain the value specified by the poison, and the reporting of the page should not change that value. Acked-by: David Hildenbrand <david@redhat.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Message-Id: <20200527041400.12700.33251.stgit@localhost.localdomain>
2019-07-25virtio-balloon: Use temporary PBP onlyDavid Hildenbrand
We still have multiple issues in the current code - The PBP is not freed during unrealize() - The PBP is not reset on device resets: After a reset, the PBP is stale. - We are not indicating VIRTIO_BALLOON_F_MUST_TELL_HOST, therefore guests (esp. legacy guests) will reuse pages without deflating, turning the PBP stale. Adding that would require compat handling. Instead, let's use the PBP only temporarily, when processing one bulk of inflation requests. This will keep guest_page_size > 4k working (with Linux guests). There is nothing to do for deflation requests anymore. The pbp is only used for a limited amount of time. Fixes: ed48c59875b6 ("virtio-balloon: Safely handle BALLOON_PAGE_SIZE < host page size") Cc: qemu-stable@nongnu.org #v4.0.0 Suggested-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20190722134108.22151-7-david@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: David Gibson <david@gibson.dropbear.id.au>
2019-07-12virtio-balloon: fix QEMU 4.0 config size migration incompatibilityStefan Hajnoczi
The virtio-balloon config size changed in QEMU 4.0 even for existing machine types. Migration from QEMU 3.1 to 4.0 can fail in some circumstances with the following error: qemu-system-x86_64: get_pci_config_device: Bad config data: i=0x10 read: a1 device: 1 cmask: ff wmask: c0 w1cmask:0 This happens because the virtio-balloon config size affects the VIRTIO Legacy I/O Memory PCI BAR size. Introduce a qdev property called "qemu-4-0-config-size" and enable it only for the QEMU 4.0 machine types. This way <4.0 machine types use the old size, 4.0 uses the larger size, and >4.0 machine types use the appropriate size depending on enabled virtio-balloon features. Live migration to and from old QEMUs to QEMU 4.1 works again as long as a versioned machine type is specified (do not use just "pc"!). Originally-by: Wolfgang Bumiller <w.bumiller@proxmox.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20190710141440.27635-1-stefanha@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Tested-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Tested-by: Wolfgang Bumiller <w.bumiller@proxmox.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-06virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINTWei Wang
The new feature enables the virtio-balloon device to receive hints of guest free pages from the free page vq. A notifier is registered to the migration precopy notifier chain. The notifier calls free_page_start after the migration thread syncs the dirty bitmap, so that the free page optimization starts to clear bits of free pages from the bitmap. It calls the free_page_stop before the migration thread syncs the bitmap, which is the end of the current round of ram save. The free_page_stop is also called to stop the optimization in the case when there is an error occurred in the process of ram saving. Note: balloon will report pages which were free at the time of this call. As the reporting happens asynchronously, dirty bit logging must be enabled before this free_page_start call is made. Guest reporting must be disabled before the migration dirty bitmap is synchronized. Signed-off-by: Wei Wang <wei.w.wang@intel.com> CC: Michael S. Tsirkin <mst@redhat.com> CC: Dr. David Alan Gilbert <dgilbert@redhat.com> CC: Juan Quintela <quintela@redhat.com> CC: Peter Xu <peterx@redhat.com> Message-Id: <1544516693-5395-8-git-send-email-wei.w.wang@intel.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> dgilbert: Dropped kernel header update, fixed up CMD_ID_* name change
2019-02-22virtio-balloon: Safely handle BALLOON_PAGE_SIZE < host page sizeDavid Gibson
The virtio-balloon always works in units of 4kiB (BALLOON_PAGE_SIZE), but we can only actually discard memory in units of the host page size. Now, we handle this very badly: we silently ignore balloon requests that aren't host page aligned, and for requests that are host page aligned we discard the entire host page. The latter can corrupt guest memory if its page size is smaller than the host's. The obvious choice would be to disable the balloon if the host page size is not 4kiB. However, that would break the special case where host and guest have the same page size, but that's larger than 4kiB. That case currently works by accident[1] - and is used in practice on many production POWER systems where 64kiB has long been the Linux default page size on both host and guest. To make the balloon safe, without breaking that useful special case, we need to accumulate 4kiB balloon requests until we have a whole contiguous host page to discard. We could in principle do that across all guest memory, but it would require a large bitmap to track. This patch represents a compromise: we track ballooned subpages for a single contiguous host page at a time. This means that if the guest discards all 4kiB chunks of a host page in succession, we will discard it. This is the expected behaviour in the (host page) == (guest page) != 4kiB case we want to support. If the guest scatters 4kiB requests across different host pages, we don't discard anything, and issue a warning. Not ideal, but at least we don't corrupt guest memory as the previous version could. Warning reporting is kind of a compromise here. Determining whether we're in a problematic state at realize() time is tricky, because we'd have to look at the host pagesizes of all memory backends, but we can't really know if some of those backends could be for special purpose memory that's not subject to ballooning. Reporting only when the guest tries to balloon a partial page also isn't great because if the guest page size happens to line up it won't indicate that we're in a non ideal situation. It could also cause alarming repeated warnings whenever a migration is attempted. So, what we do is warn the first time the guest attempts balloon a partial host page, whether or not it will end up ballooning the rest of the page immediately afterwards. [1] Because when the guest attempts to balloon a page, it will submit requests for each 4kiB subpage. Most will be ignored, but the one which happens to be host page aligned will discard the whole lot. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Message-Id: <20190214043916.22128-6-david@gibson.dropbear.id.au> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-20trivial: Do not include pci.h if it is not necessaryThomas Huth
There is no need to include pci.h in these files. Signed-off-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-07-12Clean up ill-advised or unusual header guardsMarkus Armbruster
Cleaned up with scripts/clean-header-guards.pl. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-02-06virtio: move allocation to virtqueue_pop/vring_popPaolo Bonzini
The return code of virtqueue_pop/vring_pop is unused except to check for errors or 0. We can thus easily move allocation inside the functions and just return a pointer to the VirtQueueElement. The advantage is that we will be able to allocate only the space that is needed for the actual size of the s/g list instead of the full VIRTQUEUE_MAX_SIZE items. Currently VirtQueueElement takes about 48K of memory, and this kind of allocation puts a lot of stress on malloc. By cutting the size by two or three orders of magnitude, malloc can use much more efficient algorithms. The patch is pretty large, but changes to each device are testable more or less independently. Splitting it would mostly add churn. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-06-23balloon: add a feature bit to let Guest OS deflate balloon on oomDenis V. Lunev
Excessive virtio_balloon inflation can cause invocation of OOM-killer, when Linux is under severe memory pressure. Various mechanisms are responsible for correct virtio_balloon memory management. Nevertheless it is often the case that these control tools does not have enough time to react on fast changing memory load. As a result OS runs out of memory and invokes OOM-killer. The balancing of memory by use of the virtio balloon should not cause the termination of processes while there are pages in the balloon. Now there is no way for virtio balloon driver to free memory at the last moment before some process get killed by OOM-killer. This does not provide a security breach as balloon itself is running inside Guest OS and is working in the cooperation with the host. Thus some improvements from Guest side should be considered as normal. To solve the problem, introduce a virtio_balloon callback which is expected to be called from the oom notifier call chain in out_of_memory() function. If virtio balloon could release some memory, it will make the system return and retry the allocation that forced the out of memory killer to run. This behavior should be enabled if and only if appropriate feature bit is set on the device. It is off by default. This functionality was recently merged into vanilla Linux. commit 5a10b7dbf904bfe01bb9fcc6298f7df09eed77d5 Author: Raushaniya Maksudova <rmaksudova@parallels.com> Date: Mon Nov 10 09:36:29 2014 +1030 This patch adds respective control bits into QEMU. It introduces deflate-on-oom option for balloon device which does the trick. Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Raushaniya Maksudova <rmaksudova@parallels.com> CC: Anthony Liguori <aliguori@amazon.com> CC: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: James Bottomley <JBottomley@Odin.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-06-10virtio_balloon: header updateMichael S. Tsirkin
add modern header Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2015-02-26virtio-balloon: use standard headersMichael S. Tsirkin
Drop code duplicated from standard headers. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
2013-04-15virtio: fix broken aliases.KONRAD Frederic
This fix the broken aliases, by renaming the devices. So: * virtio-blk => virtio-blk-device. * virtio-balloon => virtio-balloon-device. * virtio-scsi => virtio-scsi-device. All virtio-*-pci, virtio-*-s390, virtio-*-ccw didn't change. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Message-id: 1365501888-14602-1-git-send-email-fred.konrad@greensocs.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-08hw: move headers to include/Paolo Bonzini
Many of these should be cleaned up with proper qdev-/QOM-ification. Right now there are many catch-all headers in include/hw/ARCH depending on cpu.h, and this makes it necessary to compile these files per-target. However, fixing this does not belong in these patches. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>