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2015-07-20Revert "vhost-user: add multi queue support"Michael S. Tsirkin1-5/+0
This reverts commit 830d70db692e374b55555f4407f96a1ceefdcc97. The interface isn't fully backwards-compatible, which is bad. Let's redo this properly after 2.4. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-07-07Merge remote-tracking branch 'remotes/agraf/tags/signed-ppc-for-upstream' ↵Peter Maydell1-0/+18
into staging Patch queue for ppc - 2015-07-07 A few last minute PPC changes for 2.4: - spapr: Update SLOF - spapr: Fix a few bugs - spapr: Preparation for hotplug - spapr: Minor code cleanups - linux-user: Add mftb handling - kvm: Enable hugepage support with memory-backend-file - mac99: Remove nonexistent interrupt pin (Mac OS 9 fix) # gpg: Signature made Tue Jul 7 16:48:41 2015 BST using RSA key ID 03FEDC60 # gpg: Good signature from "Alexander Graf <agraf@suse.de>" # gpg: aka "Alexander Graf <alex@csgraf.de>" * remotes/agraf/tags/signed-ppc-for-upstream: (30 commits) sPAPR: Clear stale MSIx table during EEH reset sPAPR: Reenable EEH functionality on reboot sPAPR: Don't enable EEH on emulated PCI devices spapr-vty: Use TYPE_ definition instead of hardcoding spapr_vty: lookup should only return valid VTY objects spapr_pci: drop redundant args in spapr_[populate, create]_pci_child_dt spapr_pci: populate ibm,loc-code spapr_pci: enumerate and add PCI device tree xics_kvm: Don't enable KVM_CAP_IRQ_XICS if already enabled ppc: Update cpu_model in MachineState spapr: Consolidate cpu init code into a routine spapr: Reorganize CPU dt generation code cpus: Add a macro to walk CPUs in reverse spapr: Support ibm, lrdr-capacity device tree property spapr: Consider max_cpus during xics initialization Revert "hw/ppc/spapr_pci.c: Avoid functions not in glib 2.12 (g_hash_table_iter_*)" spapr_iommu: translate sPAPRTCEAccess to IOMMUAccessFlags spapr_iommu: drop erroneous check in h_put_tce_indirect() spapr_pci: set device node unit address as hex spapr_pci: encode class code including Prog IF register ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-07-07spapr: Support ibm, lrdr-capacity device tree propertyBharata B Rao1-0/+18
Add support for ibm,lrdr-capacity since this is needed by the guest kernel to know about the possible hot-pluggable CPUs and Memory. With this, pseries kernels will start reporting correct maxcpus in /sys/devices/system/cpu/possible. Also define the minimum hotpluggable memory size as 256MB. Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [agraf: Fix compile error on 32bit hosts] Signed-off-by: Alexander Graf <agraf@suse.de>
2015-07-07rocker: mark copy-to-cpu pkts as forwarding offloadedScott Feldman1-0/+4
For pkts copied to the CPU (to be processed by guest driver), mark the Rx descriptor with flag "OFFLOAD_FWD" to indicate device has already forwarded pkt. The guest driver will use this indicator to avoid duplicate forwarding in the guest OS. Examples include bcast/mcast/unknown ucast pkts flooded to bridged ports. We want to avoid both the device and the guest bridge driver flooding these pkts, which would result in duplicates pkts on the wire. Packet sampling, such as sFlow, can also use this technique to mark pkts for the guest OS to record but otherwise drop. Signed-off-by: Scott Feldman <sfeldma@gmail.com> Message-id: 1435746792-41278-5-git-send-email-sfeldma@gmail.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-06-23add pci-bridge-seatGerd Hoffmann1-0/+1
Simplifies multiseat configuration, see docs/multiseat.txt update for details. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-12rocker: Add support for phys nameDavid Ahern1-0/+1
Add ROCKER_TLV_CMD_PORT_SETTINGS_PHYS_NAME to port settings. This attribute exports the port name to the guest OS allowing it to name interfaces with sensible defaults. Mostly done by Scott for phys_id support; adapted to phys_name by David. Signed-off-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David Ahern <dsahern@gmail.com> Message-id: 1433985681-56138-2-git-send-email-sfeldma@gmail.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-06-10fw_cfg: insert fw_cfg file blobs via qemu cmdlineGabriel L. Somlo1-0/+21
Allow user supplied files to be inserted into the fw_cfg device before starting the guest. Since fw_cfg_add_file() already disallows duplicate fw_cfg file names, qemu will exit with an error message if the user supplies multiple blobs with the same fw_cfg file name, or if a blob name collides with a fw_cfg name programmatically added from within the QEMU source code. A warning message will be printed if the fw_cfg item name does not begin with the prefix "opt/", which is recommended for external, user provided blobs. Signed-off-by: Gabriel Somlo <somlo@cmu.edu> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-06-03docs: add sPAPR hotplug/dynamic-reconfiguration documentationMichael Roth1-0/+287
This adds a general overview of hotplug/dynamic-reconfiguration for sPAPR/pSeries guest. As specified in PAPR+ v2.7. Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-06-01vhost-user: add multi queue supportOuyang Changchun1-0/+5
Based on patch by Nikolay Nikolaev: Vhost-user will implement the multi queue support in a similar way to what vhost already has - a separate thread for each queue. To enable the multi queue functionality - a new command line parameter "queues" is introduced for the vhost-user netdev. Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com> Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-05-12Merge remote-tracking branch 'remotes/stefanha/tags/net-pull-request' into ↵Peter Maydell2-0/+1010
staging # gpg: Signature made Mon May 11 16:25:58 2015 BST using RSA key ID 81AB73C8 # gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" # gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>" * remotes/stefanha/tags/net-pull-request: rocker: timestamp on the debug logs helps correlate with events in the VM MAINTAINERS: add rocker rocker: add tests rocker: add new rocker switch device pci: add network device class 'other' for network switches pci: add rocker device ID rocker: add register programming guide virtio-net: use qemu_mac_strdup_printf net: add MAC address string printer Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-05-11pci: add rocker device IDScott Feldman1-0/+1
Signed-off-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: Jiri Pirko <jiri@resnulli.us> Message-id: 1426306173-24884-5-git-send-email-sfeldma@gmail.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-11rocker: add register programming guideScott Feldman1-0/+1009
This is the register programming guide for the Rocker device. It's intended for driver writers and device writers. It covers the device's PCI space, the register set, DMA interface, and interrupts. Signed-off-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: Jiri Pirko <jiri@resnulli.us> Message-id: 1426306173-24884-4-git-send-email-sfeldma@gmail.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-04-27acpi: add hardware implementation for memory hot unplugZhu Guihua1-2/+9
- implements QEMU hardware part of memory hot unplug protocol described at "docs/spec/acpi_mem_hotplug.txt" - handles memory remove notification event - handles device eject notification Reviewed-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-04-27acpi: fix "Memory device control fields" registerZhu Guihua1-1/+4
0 bit in Memory device control fields must be cleared before writing to register. But now this field isn't cleared when other fields are written. To solve this bug, This patch fixes UpdateRule to WriteAsZeros in "Memory device control fields" register. Reviewed-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-04-27docs: update documentation for memory hot unplugZhu Guihua1-1/+41
Add specification about how to use memory hot unplug, and add a flow diagram to explain memory hot unplug process. Reviewed-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-04-14fw_cfg: add documentation file (docs/specs/fw_cfg.txt)Gabriel L. Somlo1-0/+205
This document covers the guest-side hardware interface, as well as the host-side programming API of QEMU's firmware configuration (fw_cfg) device. Signed-off-by: Jordan Justen <jordan.l.justen@intel.com> Signed-off-by: Gabriel Somlo <somlo@cmu.edu> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-01-26hw: misc, add educational driverJiri Slaby1-0/+110
I am using qemu for teaching the Linux kernel at our university. I wrote a simple PCI device that can answer to writes/reads, generate interrupts and perform DMA. As I am dragging it locally over 2 years, I am sending it to you now. Signed-off-by: Jiri Slaby <jslaby@suse.cz> [Fix 32-bit compilation. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-03pci: move REDHAT_SDHCI device ID to make room for RockerScott Feldman1-1/+1
The rocker device uses same PCI device ID as sdhci. Since rocker device driver has already been accepted into Linux 3.18, and REDHAT_SDHCI device ID isn't used by any drivers, it's safe to move REDHAT_SDHCI device ID, avoiding conflict with rocker. Signed-off-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15sdhci: Define SDHCI PCI idsKevin O'Connor1-0/+2
Signed-off-by: Kevin O'Connor <kevin@koconnor.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-23docs/qcow2: Limit refcount_order to [0, 6]Max Reitz1-0/+1
Specify the upper limit of refcount_order to be 6 (that is, refcount_bits = 64). Any larger value does not make much sense when all offsets, sizes, cluster counts etc. "only" have a width of 64 bit as well, and very large values would be very difficult to support. Therefore, just cap it at the largest reasonable value. Suggested-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23docs/qcow2: Correct refcount_block_entriesMax Reitz1-1/+1
A refblock entry may have a different size than 16 bits, it may even be smaller than a byte. Correct the refcount_block_entries calculation accordingly. Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-15vga-pci: add qext region to mmioGerd Hoffmann1-0/+9
Add a qemu extented register range to the standard vga mmio bar. Right nowe there are two registers: One readonly register returning the size of the region (so we can easily add more registers there if needed) and one endian control register, so guests (especially ppc) can flip the framebuffer endianness as they need it. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2014-08-15docs: Make the recommendation for the backing file name position a requirementMaria Kustova1-6/+6
The current version of the qcow2 specification recommends to save the backing file name in the end of the first cluster. It follows that the backing file name can be saved somewhere in the image, but the first cluster, which contradicts the current QEMU implementation. The patch makes the backing file name required to be placed after the header extensions in the first image cluster. Signed-off-by: Maria Kustova <maria.k@catit.be> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-29vhost-user: typo fixupsMichael S. Tsirkin1-2/+1
Fix typo in field name. Strip two consequitive empty lines. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-29vhost-user: fix regions provied with VHOST_USER_SET_MEM_TABLE messageDamjan Marion1-3/+4
Old code was affected by memory gaps which resulted in buffer pointers pointing to address outside of the mapped regions. Here we are introducing following changes: - new function qemu_get_ram_block_host_ptr() returns host pointer to the ram block, it is needed to calculate offset of specific region in the host memory - new field mmap_offset is added to the VhostUserMemoryRegion. It contains offset where specific region starts in the mapped memory. As there is stil no wider adoption of vhost-user agreement was made that we will not bump version number due to this change - other fileds in VhostUserMemoryRegion struct are not changed, as they are all needed for usermode app implementation - region data is not taken from ram_list.blocks anymore, instead we use region data which is alredy calculated for use in vhost-net - Now multiple regions can have same FD and user applicaton can call mmap() multiple times with the same FD but with different offset (user needs to take care for offset page alignment) Signed-off-by: Damjan Marion <damarion@cisco.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Damjan Marion <damarion@cisco.com>
2014-06-29vhost-user: fix wrong ids in documentationDamjan Marion1-14/+14
Signed-off-by: Damjan Marion <damarion@cisco.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-19Add vhost-user protocol documentationNikolay Nikolaev1-0/+266
This document describes the basic message format used by vhost-user for communication over a unix domain socket. The protocol is based on the existing ioctl interface used for the kernel version of vhost. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-19acpi: memory hotplug ACPI hardware implementationIgor Mammedov1-0/+44
- implements QEMU hardware part of memory hotplug protocol described at "docs/specs/acpi_mem_hotplug.txt" - handles only memory add notification event for now Signed-off-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-05-28docs: Define refcount_bits valueMaria Kustova1-2/+3
The 'refcount_bits' term used in the description of refcount block entry is not defined in the specification. The definition is added in the 'refcount_order' section where refcount_bits was used as 'width in bits'. Signed-off-by: Maria Kustova <maria.k@catit.be> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-28vga: add secondary stdvga variantGerd Hoffmann1-3/+10
Add a standard vga variant which doesn't occupy any legacy resources and thus can easily be used as secondary (or legacy-free) graphics adapter. Programming must be done using the MMIO bar. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2014-01-26acpi: ich9: add CPU hotplug handling to Q35 machineIgor Mammedov1-1/+3
.. use IO port 0cd8-0xcf7 range for CPU present bitmap Signed-off-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-10-11qcow2: Alignment of snapshot table entriesMax Reitz1-0/+3
The qcow2 specification does not explicitly state so far that every snapshot table entry is aligned to 8 bytes. QEMU, in contrast, does this alignment, thus it should be properly documented (which this patch does). Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-20docs: Fix IO port number for CPU present bitmap.Anthony PERARD1-1/+1
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com> Reviewd-By: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-08-30qcow2: Add corrupt bitMax Reitz1-1/+6
This adds an incompatible bit indicating corruption to qcow2. Any image with this bit set may not be written to unless for repairing (and subsequently clearing the bit if the repair has been successful). Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-05-01acpi_piix4: Add infrastructure to send CPU hot-plug GPE to guestIgor Mammedov1-0/+22
* introduce processor status bitmask visible to guest at 0xaf00 addr, where ACPI asl code expects it * set bit corresponding to APIC ID in processor status bitmask on receiving CPU hot-plug notification * trigger CPU hot-plug SCI, to notify guest about CPU hot-plug event Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-04-30pvpanic: add document of pvpanicHu Tao1-0/+39
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-id: a5db4ce406647e8f4663b639eae62d880531df8b.1366945969.git.hutao@cn.fujitsu.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-22Merge remote-tracking branch 'bonzini/scsi-next' into stagingAnthony Liguori1-0/+92
# By Paolo Bonzini (5) and others # Via Paolo Bonzini * bonzini/scsi-next: vhost-scsi-s390: new device supporting the tcm_vhost Linux kernel module vhost-scsi-ccw: new device supporting the tcm_vhost Linux kernel module vhost-scsi-pci: new device supporting the tcm_vhost Linux kernel module vhost-scsi: new device supporting the tcm_vhost Linux kernel module virtio: simplify Makefile conditionals virtio-scsi: create VirtIOSCSICommon vhost: Add vhost_commit callback for SeaBIOS ROM region re-mapping scsi: VMWare PVSCSI paravirtual device implementation scsi: avoid assertion failure on VERIFY command Message-id: 1366381460-6041-1-git-send-email-pbonzini@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-19scsi: VMWare PVSCSI paravirtual device implementationDmitry Fleytman1-0/+92
Signed-off-by: Dmitry Fleytman <dmitry@daynix.com> Signed-off-by: Yan Vugenfirer <yan@daynix.com> [ Rename files to vmw_pvscsi, fix setting of hostStatus in pvscsi_request_cancelled - Paolo ] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-16pci: add pci test deviceMichael S. Tsirkin1-0/+26
This device is used for kvm unit tests, currently it supports testing performance of ioeventfd. Using updated kvm unittest, here's an example output: mmio-no-eventfd:pci-mem 8796 mmio-wildcard-eventfd:pci-mem 3609 mmio-datamatch-eventfd:pci-mem 3685 portio-no-eventfd:pci-io 5287 portio-wildcard-eventfd:pci-io 1762 portio-datamatch-eventfd:pci-io 1777 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-01-09pci: use constants for devices under the 1B36 device ID, document themPaolo Bonzini1-0/+15
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-01-08ivshmem: use symbolic constant for PCI ID, add to pci-ids.txtPaolo Bonzini1-0/+2
Due to disagreement on a name that is generic enough for hw/pci/pci.h, the symbolic constants are placed in the .c files. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-01-08virtio-9p: use symbolic constant, add to pci-ids.txtPaolo Bonzini1-0/+1
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-01-08reorganize pci-ids.txtPaolo Bonzini1-13/+14
Some devices were missing, and we're using two PCI vendor ids. This patch only adds devices that are already documented in hw/pci/pci.h. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-01-08docs: move pci-ids.txt to docs/specs/Paolo Bonzini1-0/+31
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-11-16vga: fix bochs alignment issueGerd Hoffmann1-1/+2
The bochs dispi interface traditionally uses port 0x1ce as 16bit index register and port 0x1cf as 16bit data register. The later is unaligned, and probably for that reason the the data register was moved to 0x1d0 for non-x86 archs. This patch makes the data register available at 0x1d0 on x86 too. The old x86 location is kept for compatibility reasons, so both 0x1cf and 0x1d0 can be used as data register on x86. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-10-22serial: add pci-serial documentationGerd Hoffmann1-0/+34
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-10-20vga: add specs for standard vgaGerd Hoffmann1-0/+64
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-09-14Spelling fixes in comments and documentationStefan Weil1-1/+1
These wrong spellings were detected by codespell: * successully -> successfully * alot -> a lot * wanna -> want to * infomation -> information * occured -> occurred ["also is" -> "is also" and "ressources" -> "resources" suggested by Peter Maydell <peter.maydell@linaro.org>] Signed-off-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-08-06docs: add lazy refcounts bit to qcow2 specificationStefan Hajnoczi1-1/+6
The lazy refcounts bit indicates that this image can take advantage of the dirty bit and that refcount updates can be postponed. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-08-06docs: add dirty bit to qcow2 specificationStefan Hajnoczi1-1/+6
The dirty bit will make it possible to perform lazy refcount updates, where the image file is not kept consistent all the time. Upon opening a dirty image file, it is necessary to perform a consistency check and repair any incorrect refcounts. Therefore the dirty bit must be an incompatible feature bit. We don't want old programs accessing a file with stale refcounts. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>