Avoid a race as described in the code comment.

Also remove a related smp_wmb() from booke's kvmppc_prepare_to_enter().
I can't see any reason for it, and the book3s_pr version doesn't have it.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This removes the powerpc "generic" updates of vcpu->cpu in load and
put, and moves them to the various backends.

The reason is that "HV" KVM does its own sauce with that field
and the generic updates might corrupt it. The field contains the
CPU# of the -first- HW CPU of the core always for all the VCPU
threads of a core (the one that's online from a host Linux
perspective).

However, the preempt notifiers are going to be called on the
threads VCPUs when they are running (due to them sleeping on our
private waitqueue) causing unload to be called, potentially
clobbering the value.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This adds an implementation of kvm_arch_flush_shadow_memslot for
Book3S HV, and arranges for kvmppc_core_commit_memory_region to
flush the dirty log when modifying an existing slot.  With this,
we can handle deletion and modification of memory slots.

kvm_arch_flush_shadow_memslot calls kvmppc_core_flush_memslot, which
on Book3S HV now traverses the reverse map chains to remove any HPT
(hashed page table) entries referring to pages in the memslot.  This
gets called by generic code whenever deleting a memslot or changing
the guest physical address for a memslot.

We flush the dirty log in kvmppc_core_commit_memory_region for
consistency with what x86 does.  We only need to flush when an
existing memslot is being modified, because for a new memslot the
rmap array (which stores the dirty bits) is all zero, meaning that
every page is considered clean already, and when deleting a memslot
we obviously don't care about the dirty bits any more.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Now that we have an architecture-specific field in the kvm_memory_slot
structure, we can use it to store the array of page physical addresses
that we need for Book3S HV KVM on PPC970 processors.  This reduces the
size of struct kvm_arch for Book3S HV, and also reduces the size of
struct kvm_arch_memory_slot for other PPC KVM variants since the fields
in it are now only compiled in for Book3S HV.

This necessitates making the kvm_arch_create_memslot and
kvm_arch_free_memslot operations specific to each PPC KVM variant.
That in turn means that we now don't allocate the rmap arrays on
Book3S PR and Book E.

Since we now unpin pages and free the slot_phys array in
kvmppc_core_free_memslot, we no longer need to do it in
kvmppc_core_destroy_vm, since the generic code takes care to free
all the memslots when destroying a VM.

We now need the new memslot to be passed in to
kvmppc_core_prepare_memory_region, since we need to initialize its
arch.slot_phys member on Book3S HV.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

When running on HV aware hosts, we can not trap when the guest sets the FP
bit, so we just let it do so when it wants to, because it has full access to
MSR.

For non-HV aware hosts with an FPU (like 440), we need to also adjust the
shadow MSR though. Otherwise the guest gets an FP unavailable trap even when
it really enabled the FP bit in MSR.
Signed-off-by: NAlexander Graf <agraf@suse.de>

IAC/DAC are defined as 32 bit while they are 64 bit wide. So ONE_REG
interface is added to set/get them.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This patch adds the watchdog emulation in KVM. The watchdog
emulation is enabled by KVM_ENABLE_CAP(KVM_CAP_PPC_BOOKE_WATCHDOG) ioctl.
The kernel timer are used for watchdog emulation and emulates
h/w watchdog state machine. On watchdog timer expiry, it exit to QEMU
if TCR.WRC is non ZERO. QEMU can reset/shutdown etc depending upon how
it is configured.
Signed-off-by: NLiu Yu <yu.liu@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>
[bharat.bhushan@freescale.com: reworked patch]
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
[agraf: adjust to new request framework]
Signed-off-by: NAlexander Graf <agraf@suse.de>

Requests may want to tell us that we need to go back into host state,
so add a return value for the checks.
Signed-off-by: NAlexander Graf <agraf@suse.de>

Our prepare_to_enter helper wants to be able to return in more circumstances
to the host than only when an interrupt is pending. Broaden the interface a
bit and move even more generic code to the generic helper.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We need to call kvm_guest_enter in booke and book3s, so move its
call to generic code.
Signed-off-by: NAlexander Graf <agraf@suse.de>

Today, we disable preemption while inside guest context, because we need
to expose to the world that we are not in a preemptible context. However,
during that time we already have interrupts disabled, which would indicate
that we are in a non-preemptible context.

The reason the checks for irqs_disabled() fail for us though is that we
manually control hard IRQs and ignore all the lazy EE framework. Let's
stop doing that. Instead, let's always use lazy EE to indicate when we
want to disable IRQs, but do a special final switch that gets us into
EE disabled, but soft enabled state. That way when we get back out of
guest state, we are immediately ready to process interrupts.

This simplifies the code drastically and reduces the time that we appear
as preempt disabled.
Signed-off-by: NAlexander Graf <agraf@suse.de>

When getting out of __vcpu_run, let's be consistent about the state we
return in. We want to always

  * have IRQs enabled
  * have called kvm_guest_exit before
Signed-off-by: NAlexander Graf <agraf@suse.de>

The x86 implementation of KVM accounts for host time while processing
guest exits. Do the same for us.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We only need to set vcpu->mode to outside once.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We need to do the same things when preparing to enter a guest for booke and
book3s_pr cores. Fold the generic code into a generic function that both call.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We only call kvmppc_check_requests() when vcpu->requests != 0, so drop
the redundant check in the function itself
Signed-off-by: NAlexander Graf <agraf@suse.de>

Without trace points, debugging what exactly is going on inside guest
code can be very tricky. Add a few more trace points at places that
hopefully tell us more when things go wrong.
Signed-off-by: NAlexander Graf <agraf@suse.de>

The e500 target has lived without mmu notifiers ever since it got
introduced, but fails for the user space check on them with hugetlbfs.

So in order to get that one working, implement mmu notifiers in a
reasonably dumb fashion and be happy. On embedded hardware, we almost
never end up with mmu notifier calls, since most people don't overcommit.
Signed-off-by: NAlexander Graf <agraf@suse.de>

Generic KVM code might want to know whether we are inside guest context
or outside. It also wants to be able to push us out of guest context.

Add support to the BookE code for the generic vcpu->mode field that describes
the above states.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We need a central place to check for pending requests in. Add one that
only does the timer check we already do in a different place.

Later, this central function can be extended by more checks.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We're already counting remote TLB flushes in a variable, but don't export
it to user space yet. Do so, so we know what's going on.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We want to have tracing information on guest exits for booke as well
as book3s. Since most information is identical, use a common trace point.
Signed-off-by: NAlexander Graf <agraf@suse.de>

Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Added the decrementer auto-reload support. DECAR is readable
on e500v2/e500mc and later cpus.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

When running kvm_vcpu_block and it realizes that the CPU is actually good
to run, we get a request bit set for KVM_REQ_UNHALT. Right now, there's
nothing we can do with that bit, so let's unset it right after the call
again so we don't get confused in our later checks for pending work.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When emulating updating load/store instructions (lwzu, stwu, ...) we need to
write the effective address of the load/store into a register.

Currently, we write the physical address in there, which is very wrong. So
instead let's save off where the virtual fault was on MMIO and use that
information as value to put into the register.

While at it, also move the XOP variants of the above instructions to the new
scheme of using the already known vaddr instead of calculating it themselves.
Reported-by: NJörg Sommer <joerg@alea.gnuu.de>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

So far, we've always called prepare_to_enter even when all we did was return
to the host. This patch changes that semantic to only call prepare_to_enter
when we actually want to get back into the guest.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When we get a performance monitor interrupt, we need to make sure that
the host receives it. So reinject it like we reinject the other host
destined interrupts.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When reinjecting an interrupt into the host interrupt handler after we're
back in host kernel land, we need to tell the kernel where the interrupt
happened. We can't tell it that we were in guest state, because that might
lead to random code walking host addresses. So instead, we tell it that
we came from the interrupt reinject code.

This helps getting reasonable numbers out of perf.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When during guest context we get a performance monitor interrupt, we
currently bail out and oops. Let's route it to its correct handler
instead.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The comment for program interrupts triggered when using bookehv was
misleading. Update it to mention why MSR_GS indicates that we have
to inject an interrupt into the guest again, not emulate it.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When during guest execution we get a machine check interrupt, we don't
know how to handle it yet. So let's add the error printing code back
again that we dropped accidently earlier and tell user space that something
went really wrong.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The semantics of BOOKE_IRQPRIO_MAX changed to denote the highest available
irqprio + 1, so let's reflect that in the code too.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Instead of checking whether we should reschedule only when we exited
due to an interrupt, let's always check before entering the guest back
again. This gets the target more in line with the other archs.

Also while at it, generalize the whole thing so that eventually we could
have a single kvmppc_prepare_to_enter function for all ppc targets that
does signal and reschedule checking for us.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When we fail to emulate an instruction for the guest, we better go in and
tell it that we failed to emulate it, by throwing an illegal instruction
exception.

Please beware that we basically never get around to telling the guest that
we failed thanks to the debugging code right above it. If user space however
decides that it wants to ignore the debug, we would at least do "the right
thing" afterwards.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The e500mc patches left some debug code in that we don't need. Remove it.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The CONFIG_KVM_E500 option really indicates that we're running on a V2 machine,
not on a machine of the generic E500 class. So indicate that properly and
change the config name accordingly.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When setting MSR for an e500mc guest, we implicitly always set MSR_GS
to make sure the guest is in guest state. Since we have this implicit
rule there, we don't need to explicitly pass MSR_GS to set_msr().

Remove all explicit setters of MSR_GS.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When one vcpu wants to kick another, it can issue a special IPI instruction
called msgsnd. This patch emulates this instruction, its clearing counterpart
and the infrastructure required to actually trigger that interrupt inside
a guest vcpu.

With this patch, SMP guests on e500mc work.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

e500mc has a normal PPC FPU, rather than SPE which is found
on e500v1/v2.

Based on code from Liu Yu <yu.liu@freescale.com>.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>