kvm_vm_ioctl_get_dirty_log scans bitmap to see it it's all zero, but
doesn't use that information.

Avi says:
	Looks like it was used to guard	kvm_mmu_slot_remove_write_access();
	optimizing the case where the guest just leaves the screen alone (which
	it usually does, especially in benchmarks).

	I'd rather reinstate that optimization.  See
	90cb0529 where the damage was done.

It's pretty simple: if the bitmap is all zero, we don't need to do anything to
clean it.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Now we use a kmem cache for allocating vcpus, we can get the 16-byte
alignment required by fxsave & fxrstor instructions, and avoid
manually aligning the buffer.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Avi wants the allocations of vcpus centralized again.  The easiest way
is to add a "size" arg to kvm_init_arch, and expose the thus-prepared
cache to the modules.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

... in favor of the more general emulator_{read,write}_*.
Signed-off-by: NLaurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

... instead of a x86_emulate_ctxt, so that other callers can use it easily.
Signed-off-by: NLaurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

There are several places where hardcoded numbers are used in place of
the easily-available constant, which is poor form.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Now that kvm generally runs with preemption enabled, we need to protect
the fpu intialization sequence.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This allows the kvm mmu to perform sleepy operations, such as memory
allocation.
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Current kvm disables preemption while the new virtualization registers are
in use.  This of course is not very good for latency sensitive workloads (one
use of virtualization is to offload user interface and other latency
insensitive stuff to a container, so that it is easier to analyze the
remaining workload).  This patch re-enables preemption for kvm; preemption
is now only disabled when switching the registers in and out, and during
the switch to guest mode and back.

Contains fixes from Shaohua Li <shaohua.li@intel.com>.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

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: NJeff Dike <jdike@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patch converts the vcpus array in "struct kvm" to a pointer
array, and changes the "vcpu_create" and "vcpu_setup" hooks into one
"vcpu_create" call which does the allocation and initialization of the
vcpu (calling back into the kvm_vcpu_init core helper).
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

struct kvm_vcpu has vmx-specific members; remove them to a private structure.
Signed-off-by: NGregory Haskins <ghaskins@novell.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

load_pdptrs can be handed an invalid cr3, and it should not oops.
This can happen because we injected #gp in set_cr3() after we set
vcpu->cr3 to the invalid value, or from kvm_vcpu_ioctl_set_sregs(), or
memory configuration changes after the guest did set_cr3().

We should also copy the pdpte array once, before checking and
assigning, otherwise an SMP guest can potentially alter the values
between the check and the set.

Finally one nitpick: ret = 1 should be done as late as possible: this
allows GCC to check for unset "ret" should the function change in
future.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

gfn_to_page might sleep with swap support. Move it out of the kmap calls.
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Don't fall through and turn on PAE in this case.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Intel manual (and KVM definition) say the TPR is 4 bits wide.  Also fix
CR8_RESEVED_BITS typo.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Signed-off-by: NJeff Dike <jdike@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

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: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

On this machine (Intel), writing to the CR4 bits 0x00000800 and
0x00001000 cause a GPF.  The Intel manual is a little unclear, but
AFIACT they're reserved, too.

Also fix spelling of CR4_RESEVED_BITS.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

The kernel now has asm/cpu-features.h: use those macros instead of inventing
our own.

Also spell out definition of CR3_RESEVED_BITS, fix spelling and
tighten it for the non-PAE case.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

The kernel now has asm/cpu-features.h: use those macros instead of
inventing our own.

Also spell out definition of CR0_RESEVED_BITS (no code change) and fix typo.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Don't pre-declare hardware_disable: shuffle the reboot hook down.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Add string pio write support to support some version of Windows.
Signed-off-by: NYaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patch adds a `vcpu_id' field in `struct vcpu', so we can
differentiate BSP and APs without pointer comparison or arithmetic.
Signed-off-by: NQing He <qing.he@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

*nopage() in kvm_main.c should only store the type of mmap() fault if
the pointers are not NULL. This patch fixes the problem.
Signed-off-by: NNguyen Anh Quynh <aquynh@gmail.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

When taking a cpu down, we need to hardware_disable() it.
Unfortunately, the CPU_DYING notifier is called with interrupts
disabled, which means we can't use smp_call_function_single().

Fortunately, the CPU_DYING notifier is always called on the dying cpu,
so we don't need to use the function at all and can simply call
hardware_disable() directly.
Tested-by: NPaolo Ornati <ornati@fastwebnet.it>
Signed-off-by: NAvi Kivity <avi@qumranet.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Testing the wrong bit caused kvm not to disable nx on the guest when it is
disabled on the host (an mmu optimization relies on the nx bits being the
same in the guest and host).

This allows Windows to boot when nx is disabled on te host (e.g. when
host pae is disabled).
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This reverts commit a3c870bd.  While it
does save useless updates, it (probably) defeats the fork detector, causing
a massive performance loss.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

We add the kvm to the vm_list before initializing the vcpu mutexes,
which can be mutex_trylock()'ed by decache_vcpus_on_cpu().
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Writes that are contiguous in virtual memory may not be contiguous in
physical memory; so split writes that straddle a page boundary.

Thanks to Aurelien for reporting the bug, patient testing, and a fix
to this very patch.
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Allow real-mode emulation of rdmsr and wrmsr.  This allows smp Windows to
boot, presumably for its sipi trampoline.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

The memory slot management functions were oriented against vcpu 0, where
they should be kvm-wide.  This causes hangs starting X on guest smp.

Fix by making the functions (and resultant tail in the mmu) non-vcpu-specific.
Unfortunately this reduces the efficiency of the mmu object cache a bit.  We
may have to revisit this later.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Only at the CPU_DYING stage can we be sure that no user process will
be scheduled onto the cpu and oops when trying to use virtualization
extensions.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

The hotplug IPIs can be called from the cpu on which we are currently
running on, so use on_cpu().  Similarly, drop on_each_cpu() for the
suspend/resume callbacks, as we're in atomic context here and only one
cpu is up anyway.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

By keeping track of which cpus have virtualization enabled, we
prevent double-enable or double-disable during hotplug, which is a
very fatal oops.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Remove unnecessary ones, and rearange the remaining in the standard order.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

kvm uses a pseudo filesystem, kvmfs, to generate inodes, a job that the
new anonymous inodes source does much better.

Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

When writing to normal memory and the memory area is unchanged the write
can be safely skipped, avoiding the costly kvm_mmu_pte_write.
Signed-Off-By: NLuca Tettamanti <kronos.it@gmail.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Useful for the PIC and PIT.
Signed-off-by: NYaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Signed-off-by: NGregory Haskins <ghaskins@novell.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>