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path: root/include/linux/kvm.h
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2008-08-25KVM: fix userspace ABI breakageAdrian Bunk
The following part of commit 9ef621d3be56e1188300476a8102ff54f7b6793f (KVM: Support mixed endian machines) changed on the size of a struct that is exported to userspace: include/linux/kvm.h: @@ -318,14 +318,14 @@ struct kvm_trace_rec { __u32 vcpu_id; union { struct { - __u32 cycle_lo, cycle_hi; + __u64 cycle_u64; __u32 extra_u32[KVM_TRC_EXTRA_MAX]; } cycle; struct { __u32 extra_u32[KVM_TRC_EXTRA_MAX]; } nocycle; } u; -}; +} __attribute__((packed)); Packing a struct was the correct idea, but it packed the wrong struct. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-29KVM: Advertise synchronized mmu support to userspaceAvi Kivity
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20KVM: Support mixed endian machinesTan, Li
Currently kvmtrace is not portable. This will prevent from copying a trace file from big-endian target to little-endian workstation for analysis. In the patch, kernel outputs metadata containing a magic number to trace log, and changes 64-bit words to be u64 instead of a pair of u32s. Signed-off-by: Tan Li <li.tan@intel.com> Acked-by: Jerone Young <jyoung5@us.ibm.com> Acked-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20KVM: Add coalesced MMIO support (common part)Laurent Vivier
This patch adds all needed structures to coalesce MMIOs. Until an architecture uses it, it is not compiled. Coalesced MMIO introduces two ioctl() to define where are the MMIO zones that can be coalesced: - KVM_REGISTER_COALESCED_MMIO registers a coalesced MMIO zone. It requests one parameter (struct kvm_coalesced_mmio_zone) which defines a memory area where MMIOs can be coalesced until the next switch to user space. The maximum number of MMIO zones is KVM_COALESCED_MMIO_ZONE_MAX. - KVM_UNREGISTER_COALESCED_MMIO cancels all registered zones inside the given bounds (bounds are also given by struct kvm_coalesced_mmio_zone). The userspace client can check kernel coalesced MMIO availability by asking ioctl(KVM_CHECK_EXTENSION) for the KVM_CAP_COALESCED_MMIO capability. The ioctl() call to KVM_CAP_COALESCED_MMIO will return 0 if not supported, or the page offset where will be stored the ring buffer. The page offset depends on the architecture. After an ioctl(KVM_RUN), the first page of the KVM memory mapped points to a kvm_run structure. The offset given by KVM_CAP_COALESCED_MMIO is an offset to the coalesced MMIO ring expressed in PAGE_SIZE relatively to the address of the start of th kvm_run structure. The MMIO ring buffer is defined by the structure kvm_coalesced_mmio_ring. [akio: fix oops during guest shutdown] Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net> Signed-off-by: Akio Takebe <takebe_akio@jp.fujitsu.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: ppc: Add DCR access information to struct kvm_runHollis Blanchard
Device Control Registers are essentially another address space found on PowerPC 4xx processors, analogous to PIO on x86. DCRs are always 32 bits, and can be identified by a 32-bit number. We forward most DCR accesses to userspace for emulation (with the exception of CPR0 registers, which can be read directly for simplicity in timebase frequency determination). Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: add ioctls to save/store mpstateMarcelo Tosatti
So userspace can save/restore the mpstate during migration. [avi: export the #define constants describing the value] [christian: add s390 stubs] [avi: ditto for ia64] Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: Add trace markersFeng (Eric) Liu
Trace markers allow userspace to trace execution of a virtual machine in order to monitor its performance. Signed-off-by: Feng (Eric) Liu <eric.e.liu@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: s390: intercepts for diagnose instructionsChristian Borntraeger
This patch introduces interpretation of some diagnose instruction intercepts. Diagnose is our classic architected way of doing a hypercall. This patch features the following diagnose codes: - vm storage size, that tells the guest about its memory layout - time slice end, which is used by the guest to indicate that it waits for a lock and thus cannot use up its time slice in a useful way - ipl functions, which a guest can use to reset and reboot itself In order to implement ipl functions, we also introduce an exit reason that causes userspace to perform various resets on the virtual machine. All resets are described in the principles of operation book, except KVM_S390_RESET_IPL which causes a reboot of the machine. Acked-by: Martin Schwidefsky <martin.schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: s390: interrupt subsystem, cpu timer, waitpswCarsten Otte
This patch contains the s390 interrupt subsystem (similar to in kernel apic) including timer interrupts (similar to in-kernel-pit) and enabled wait (similar to in kernel hlt). In order to achieve that, this patch also introduces intercept handling for instruction intercepts, and it implements load control instructions. This patch introduces an ioctl KVM_S390_INTERRUPT which is valid for both the vm file descriptors and the vcpu file descriptors. In case this ioctl is issued against a vm file descriptor, the interrupt is considered floating. Floating interrupts may be delivered to any virtual cpu in the configuration. The following interrupts are supported: SIGP STOP - interprocessor signal that stops a remote cpu SIGP SET PREFIX - interprocessor signal that sets the prefix register of a (stopped) remote cpu INT EMERGENCY - interprocessor interrupt, usually used to signal need_reshed and for smp_call_function() in the guest. PROGRAM INT - exception during program execution such as page fault, illegal instruction and friends RESTART - interprocessor signal that starts a stopped cpu INT VIRTIO - floating interrupt for virtio signalisation INT SERVICE - floating interrupt for signalisations from the system service processor struct kvm_s390_interrupt, which is submitted as ioctl parameter when injecting an interrupt, also carrys parameter data for interrupts along with the interrupt type. Interrupts on s390 usually have a state that represents the current operation, or identifies which device has caused the interruption on s390. kvm_s390_handle_wait() does handle waitpsw in two flavors: in case of a disabled wait (that is, disabled for interrupts), we exit to userspace. In case of an enabled wait we set up a timer that equals the cpu clock comparator value and sleep on a wait queue. [christian: change virtio interrupt to 0x2603] Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: s390: sie intercept handlingChristian Borntraeger
This path introduces handling of sie intercepts in three flavors: Intercepts are either handled completely in-kernel by kvm_handle_sie_intercept(), or passed to userspace with corresponding data in struct kvm_run in case kvm_handle_sie_intercept() returns -ENOTSUPP. In case of partial execution in kernel with the need of userspace support, kvm_handle_sie_intercept() may choose to set up struct kvm_run and return -EREMOTE. The trivial intercept reasons are handled in this patch: handle_noop() just does nothing for intercepts that don't require our support at all handle_stop() is called when a cpu enters stopped state, and it drops out to userland after updating our vcpu state handle_validity() faults in the cpu lowcore if needed, or passes the request to userland Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: s390: arch backend for the kvm kernel moduleHeiko Carstens
This patch contains the port of Qumranet's kvm kernel module to IBM zSeries (aka s390x, mainframe) architecture. It uses the mainframe's virtualization instruction SIE to run virtual machines with up to 64 virtual CPUs each. This port is only usable on 64bit host kernels, and can only run 64bit guest kernels. However, running 31bit applications in guest userspace is possible. The following source files are introduced by this patch arch/s390/kvm/kvm-s390.c similar to arch/x86/kvm/x86.c, this implements all arch callbacks for kvm. __vcpu_run calls back into sie64a to enter the guest machine context arch/s390/kvm/sie64a.S assembler function sie64a, which enters guest context via SIE, and switches world before and after that include/asm-s390/kvm_host.h contains all vital data structures needed to run virtual machines on the mainframe include/asm-s390/kvm.h defines kvm_regs and friends for user access to guest register content arch/s390/kvm/gaccess.h functions similar to uaccess to access guest memory arch/s390/kvm/kvm-s390.h header file for kvm-s390 internals, extended by later patches Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: kvm.h: __user requires compiler.hChristian Borntraeger
include/linux/kvm.h defines struct kvm_dirty_log to [...] union { void __user *dirty_bitmap; /* one bit per page */ __u64 padding; }; __user requires compiler.h to compile. Currently, this works on x86 only coincidentally due to other include files. This patch makes kvm.h compile in all cases. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: MMU: hypercall based pte updates and TLB flushesMarcelo Tosatti
Hypercall based pte updates are faster than faults, and also allow use of the lazy MMU mode to batch operations. Don't report the feature if two dimensional paging is enabled. [avi: - one mmu_op hypercall instead of one per op - allow 64-bit gpa on hypercall - don't pass host errors (-ENOMEM) to guest] [akpm: warning fix on i386] Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: add basic paravirt supportMarcelo Tosatti
Add basic KVM paravirt support. Avoid vm-exits on IO delays. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: Add save/restore supporting of in kernel PITSheng Yang
Signed-off-by: Sheng Yang <sheng.yang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: In kernel PIT modelSheng Yang
The patch moves the PIT model from userspace to kernel, and increases the timer accuracy greatly. [marcelo: make last_injected_time per-guest] Signed-off-by: Sheng Yang <sheng.yang@intel.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Tested-and-Acked-by: Alex Davis <alex14641@yahoo.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: Add API for determining the number of supported memory slotsAvi Kivity
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: Add API to retrieve the number of supported vcpus per vmAvi Kivity
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: paravirtualized clocksource: host partGlauber de Oliveira Costa
This is the host part of kvm clocksource implementation. As it does not include clockevents, it is a fairly simple implementation. We only have to register a per-vcpu area, and start writing to it periodically. The area is binary compatible with xen, as we use the same shadow_info structure. [marcelo: fix bad_page on MSR_KVM_SYSTEM_TIME] [avi: save full value of the msr, even if enable bit is clear] [avi: clear previous value of time_page] Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-03-03KVM: Make the supported cpuid list a host property rather than a vm propertyAvi Kivity
One of the use cases for the supported cpuid list is to create a "greatest common denominator" of cpu capabilities in a server farm. As such, it is useful to be able to get the list without creating a virtual machine first. Since the code does not depend on the vm in any way, all that is needed is to move it to the device ioctl handler. The capability identifier is also changed so that binaries made against -rc1 will fail gracefully. Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Portability: Move kvm_fpu to asm-x86/kvm.hChristian Ehrhardt
This patch moves kvm_fpu asm-x86/kvm.h to allow every architecture to define an own representation used for KVM_GET_FPU/KVM_SET_FPU. Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Acked-by: Carsten Otte <cotte@de.ibm.com> Acked-by: Zhang Xiantao <xiantao.zhang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Accelerated apic supportAvi Kivity
This adds a mechanism for exposing the virtual apic tpr to the guest, and a protocol for letting the guest update the tpr without causing a vmexit if conditions allow (e.g. there is no interrupt pending with a higher priority than the new tpr). Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: local APIC TPR access reporting facilityAvi Kivity
Add a facility to report on accesses to the local apic tpr even if the local apic is emulated in the kernel. This is basically a hack that allows userspace to patch Windows which tends to bang on the tpr a lot. Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Expose ioapic to ia64 save/restore APIsZhang Xiantao
IA64 also needs to see ioapic structure in irqchip. Signed-off-by: xiantao.zhang@intel.com <xiantao.zhang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Add ifdef in irqchip struct for x86 only structuresJerone Young
This patch fixes a small issue where sturctures: kvm_pic_state kvm_ioapic_state are defined inside x86 specific code and may or may not be defined in anyway for other architectures. The problem caused is one cannot compile userspace apps (ex. libkvm) for other archs since a size cannot be determined for these structures. Signed-off-by: Jerone Young <jyoung5@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Enhance guest cpuid managementDan Kenigsberg
The current cpuid management suffers from several problems, which inhibit passing through the host feature set to the guest: - No way to tell which features the host supports While some features can be supported with no changes to kvm, others need explicit support. That means kvm needs to vet the feature set before it is passed to the guest. - No support for indexed or stateful cpuid entries Some cpuid entries depend on ecx as well as on eax, or on internal state in the processor (running cpuid multiple times with the same input returns different output). The current cpuid machinery only supports keying on eax. - No support for save/restore/migrate The internal state above needs to be exposed to userspace so it can be saved or migrated. This patch adds extended cpuid support by means of three new ioctls: - KVM_GET_SUPPORTED_CPUID: get all cpuid entries the host (and kvm) supports - KVM_SET_CPUID2: sets the vcpu's cpuid table - KVM_GET_CPUID2: gets the vcpu's cpuid table, including hidden state [avi: fix original KVM_SET_CPUID not removing nx on non-nx hosts as it did before] Signed-off-by: Dan Kenigsberg <danken@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Portability: Move cpuid structures to <asm/kvm.h>Jerone Young
This patch moves structures: kvm_cpuid_entry kvm_cpuid from include/linux/kvm.h to include/asm-x86/kvm.h Signed-off-by: Jerone Young <jyoung5@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Portability: Move kvm_sregs and msr structures to <asm/kvm.h>Jerone Young
Move structures: kvm_sregs kvm_msr_entry kvm_msrs kvm_msr_list from include/linux/kvm.h to include/asm-x86/kvm.h Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Portability: Move kvm_segment & kvm_dtable structure to <asm/kvm.h>Jerone Young
This patch moves structures: kvm_segment kvm_dtable from include/linux/kvm.h to include/asm-x86/kvm.h Signed-off-by: Jerone Young <jyoung5@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Portability: Move structure lapic_state to <asm/kvm.h>Jerone Young
This patch moves structure lapic_state from include/linux/kvm.h to include/asm-x86/kvm.h Signed-off-by: Jerone Young <jyoung5@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Portability: Move kvm_regs to <asm/kvm.h>Jerone Young
This patch moves structure kvm_regs to include/asm-x86/kvm.h. Each architecture will need to create there own version of this structure. Signed-off-by: Jerone Young <jyoung5@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Portability: Move x86 pic strutcturesJerone Young
This patch moves structures: kvm_pic_state kvm_ioapic_state to inclue/asm-x86/kvm.h. Signed-off-by: Jerone Young <jyoung5@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Portability: Move kvm_memory_alias to asm/kvm.hJerone Young
This patch moves sturct kvm_memory_alias from include/linux/kvm.h to include/asm-x86/kvm.h. Also have include/linux/kvm.h include include/asm/kvm.h. Signed-off-by: Jerone Young <jyoung5@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Add ioctl to tss address from userspace,Izik Eidus
Currently kvm has a wart in that it requires three extra pages for use as a tss when emulating real mode on Intel. This patch moves the allocation internally, only requiring userspace to tell us where in the physical address space we can place the tss. Signed-off-by: Izik Eidus <izike@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Support assigning userspace memory to the guestIzik Eidus
Instead of having the kernel allocate memory to the guest, let userspace allocate it and pass the address to the kernel. This is required for s390 support, but also enables features like memory sharing and using hugetlbfs backed memory. Signed-off-by: Izik Eidus <izike@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30KVM: Allow dynamic allocation of the mmu shadow cache sizeIzik Eidus
The user is now able to set how many mmu pages will be allocated to the guest. Signed-off-by: Izik Eidus <izike@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: Replace enum by #defineAvi Kivity
Easier for existence test (#ifdef) in userspace. Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: in-kernel LAPIC save and restore supportEddie Dong
This patch adds a new vcpu-based IOCTL to save and restore the local apic registers for a single vcpu. The kernel only copies the apic page as a whole, extraction of registers is left to userspace side. On restore, the APIC timer is restarted from the initial count, this introduces a little delay, but works fine. Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com> Signed-off-by: Qing He <qing.he@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: in-kernel IOAPIC save and restore supportHe, Qing
This patch adds support for in-kernel ioapic save and restore (to and from userspace). It uses the same get/set_irqchip ioctl as in-kernel PIC. Signed-off-by: Qing He <qing.he@intel.com> Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: Add get/set irqchip ioctls for in-kernel PIC live migration supportHe, Qing
This patch adds two new ioctls to dump and write kernel irqchips for save/restore and live migration. PIC s/r and l/m is implemented in this patch. Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com> Signed-off-by: Qing He <qing.he@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: Emulate hlt in the kernelEddie Dong
By sleeping in the kernel when hlt is executed, we simplify the in-kernel guest interrupt path considerably. Signed-off-by: Gregory Haskins <ghaskins@novell.com> Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: Emulate local APIC in kernelEddie Dong
Because lightweight exits (exits which don't involve userspace) are many times faster than heavyweight exits, it makes sense to emulate high usage devices in the kernel. The local APIC is one such device, especially for Windows and for SMP, so we add an APIC model to kvm. It also allows in-kernel host-side drivers to inject interrupts without going through userspace. [compile fix on i386 from Jindrich Makovicka] Signed-off-by: Yaozu (Eddie) Dong <Eddie.Dong@intel.com> Signed-off-by: Qing He <qing.he@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: Add support for in-kernel PIC emulationEddie Dong
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: Communicate cr8 changes to userspaceYang, Sheng
This allows running 64-bit Windows. Signed-off-by: Sheng Yang <sheng.yang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: add hypercall nr to kvm_runJeff Dike
Add the hypercall number to kvm_run and initialize it. This changes the ABI, but as this particular ABI was unusable before this no users are affected. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: Trivial: Use standard BITMAP macros, open-code userspace-exposed headerRusty Russell
Creating one's own BITMAP macro seems suboptimal: if we use manual arithmetic in the one place exposed to userspace, we can use standard macros elsewhere. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: Trivial: /dev/kvm interface is no longer experimental.Rusty Russell
KVM interface is no longer experimental. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13KVM: Future-proof the exit information union ABIAvi Kivity
Note that as the size of struct kvm_run is not part of the ABI, we can add things at the end. Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-05-03KVM: Remove unused 'instruction_length'Avi Kivity
As we no longer emulate in userspace, this is meaningless. We don't compute it on SVM anyway. Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-05-03KVM: Don't require explicit indication of completion of mmio or pioAvi Kivity
It is illegal not to return from a pio or mmio request without completing it, as mmio or pio is an atomic operation. Therefore, we can simplify the userspace interface by avoiding the completion indication. Signed-off-by: Avi Kivity <avi@qumranet.com>