Improve dirty bit setting for pages that kvm release, until now every page
that we released we marked dirty, from now only pages that have potential
to get dirty we mark dirty.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Meanwhile keep the interface in common, and leave as more logic in common
as possible.
Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This is a little more accurate (since it counts actual reloads, not potential
reloads), and reverses the sense of the statistic to measure a bad event like
most of the other stats (e.g. we want to minimize all counters).
Signed-off-by: Avi Kivity <avi@qumranet.com>
Add two arch hooks to handle kvm_create_vm and kvm destroy_vm. Now, just
put io_bus init and destory in common.
Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Move kvm_vcpu_ioctl_translate to arch, since mmu would be put under arch.
Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Make KVM_CHECK_EXTENSION code into a function, all archs can define its
capability independently.
Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Will be called once arch module registers itself.
Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Check for the "error hva", an address outside the user address space that
signals a bad gfn.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch based on CR8/TPR patch, and enable the TPR shadow (FlexPriority)
for 32bit Windows. Since TPR is accessed very frequently by 32bit
Windows, especially SMP guest, with FlexPriority enabled, we saw significant
performance gain.
Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch splits kvm_vm_ioctl into archtecture independent parts, and
x86 specific parts which go to kvm_arch_vcpu_ioctl in x86.c.
The patch is unchanged since last submission.
Common ioctls for all architectures are:
KVM_CREATE_VCPU, KVM_GET_DIRTY_LOG, KVM_SET_USER_MEMORY_REGION
x86 specific ioctls are:
KVM_SET_MEMORY_REGION,
KVM_GET/SET_NR_MMU_PAGES, KVM_SET_MEMORY_ALIAS, KVM_CREATE_IRQCHIP,
KVM_CREATE_IRQ_LINE, KVM_GET/SET_IRQCHIP
KVM_SET_TSS_ADDR
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
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>
Reserve a few memory slots for kernel internal use. This is good for case
you have to register memory region and you want to be sure it was not
registered from userspace, and for case you want to register a memory region
that won't be seen from userspace.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Remove kvm memory slot allocation mechanism from the ioctl
and put it to exported function.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
kvm_vm_ioctl_set_memory_region() is able to remove memory in addition to
adding it. Therefore when using kernel swapping support for old userspaces,
we need to munmap the memory if the user request to remove it
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Split guest reset code out of vmx_vcpu_setup(). Besides being cleaner, this
moves the realmode tss setup (which can sleep) outside vmx_vcpu_setup()
(which is executed with preemption enabled).
[izik: remove unused variable]
Signed-off-by: Avi Kivity <avi@qumranet.com>
First step to split kvm_vcpu. Currently, we just use an macro to define
the common fields in kvm_vcpu for all archs, and all archs need to define
its own kvm_vcpu struct.
Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Allocate a userspace buffer for older userspaces. Also eliminate phys_mem
buffer. The memset() in kvmctl really kills initial memory usage but swapping
works even with old userspaces.
A side effect is that maximum guest side is reduced for older userspace on
i386.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
ppc and s390 offer the possibility to track process times precisely
by looking at cpu timer on every context switch, irq, softirq etc.
We can use that infrastructure as well for guest time accounting.
We need to account the used time before we change the state.
This patch adds a call to account_system_vtime to kvm_guest_enter
and kvm_guest exit. If CONFIG_VIRT_CPU_ACCOUNTING is not set,
account_system_vtime is defined in hardirq.h as an empty function,
which means this patch does not change the behaviour on other
platforms.
I compile tested this patch on x86 and function tested the patch on
s390.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This allows guest memory to be swapped. Pages which are currently mapped
via shadow page tables are pinned into memory, but all other pages can
be freely swapped.
The patch makes gfn_to_page() elevate the page's reference count, and
introduces kvm_release_page() that pairs with it.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
In case the page is not present in the guest memory map, return a dummy
page the guest can scribble on.
This simplifies error checking in its users.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch splits kvm_vcpu_ioctl into archtecture independent parts, and
x86 specific parts which go to kvm_arch_vcpu_ioctl in x86.c.
Common ioctls for all architectures are:
KVM_RUN, KVM_GET/SET_(S-)REGS, KVM_TRANSLATE, KVM_INTERRUPT,
KVM_DEBUG_GUEST, KVM_SET_SIGNAL_MASK, KVM_GET/SET_FPU
Note that some PPC chips don't have an FPU, so we might need an #ifdef
around KVM_GET/SET_FPU one day.
x86 specific ioctls are:
KVM_GET/SET_LAPIC, KVM_SET_CPUID, KVM_GET/SET_MSRS
An interresting aspect is vcpu_load/vcpu_put. We now have a common
vcpu_load/put which does the preemption stuff, and an architecture
specific kvm_arch_vcpu_load/put. In the x86 case, this one calls the
vmx/svm function defined in kvm_x86_ops.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This time, the biggest change is gpa_to_hpa. The translation of GPA to HPA does
not depend on the VCPU state unlike GVA to GPA so there's no need to pass in
the kvm_vcpu.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
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>
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>
When kvm uses user-allocated pages in the future for the guest, we won't
be able to use page->private for rmap, since page->rmap is reserved for
the filesystem. So we move the rmap base pointers to the memory slot.
A side effect of this is that we need to store the gfn of each gpte in
the shadow pages, since the memory slot is addressed by gfn, instead of
hfn like struct page.
Signed-off-by: Izik Eidus <izik@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
When we allow guest page faults to reach the guests directly, we lose
the fault tracking which allows us to detect demand paging. So we provide
an alternate mechnism by clearing the accessed bit when we set a pte, and
checking it later to see if the guest actually used it.
Signed-off-by: Avi Kivity <avi@qumranet.com>
There are two classes of page faults trapped by kvm:
- host page faults, where the fault is needed to allow kvm to install
the shadow pte or update the guest accessed and dirty bits
- guest page faults, where the guest has faulted and kvm simply injects
the fault back into the guest to handle
The second class, guest page faults, is pure overhead. We can eliminate
some of it on vmx using the following evil trick:
- when we set up a shadow page table entry, if the corresponding guest pte
is not present, set up the shadow pte as not present
- if the guest pte _is_ present, mark the shadow pte as present but also
set one of the reserved bits in the shadow pte
- tell the vmx hardware not to trap faults which have the present bit clear
With this, normal page-not-present faults go directly to the guest,
bypassing kvm entirely.
Unfortunately, this trick only works on Intel hardware, as AMD lacks a
way to discriminate among page faults based on error code. It is also
a little risky since it uses reserved bits which might become unreserved
in the future, so a module parameter is provided to disable it.
Signed-off-by: Avi Kivity <avi@qumranet.com>
