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>

Chips such as e500mc that implement category E.HV in Power ISA 2.06
provide hardware virtualization features, including a new MSR mode for
guest state.  The guest OS can perform many operations without trapping
into the hypervisor, including transitions to and from guest userspace.

Since we can use SRR1[GS] to reliably tell whether an exception came from
guest state, instead of messing around with IVPR, we use DO_KVM similarly
to book3s.

Current issues include:
 - Machine checks from guest state are not routed to the host handler.
 - The guest can cause a host oops by executing an emulated instruction
   in a page that lacks read permission.  Existing e500/4xx support has
   the same problem.

Includes work by Ashish Kalra <Ashish.Kalra@freescale.com>,
Varun Sethi <Varun.Sethi@freescale.com>, and
Liu Yu <yu.liu@freescale.com>.
Signed-off-by: NScott Wood <scottwood@freescale.com>
[agraf: remove pt_regs usage]
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

e500mc will want to do lpid allocation/deallocation here.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This gives us a place to put load/put actions that correspond to
code that is booke-specific but not specific to a particular core.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This moves the get/set_one_reg implementation down from powerpc.c into
booke.c, book3s_pr.c and book3s_hv.c.  This avoids #ifdefs in C code,
but more importantly, it fixes a bug on Book3s HV where we were
accessing beyond the end of the kvm_vcpu struct (via the to_book3s()
macro) and corrupting memory, causing random crashes and file corruption.

On Book3s HV we only accept setting the HIOR to zero, since the guest
runs in supervisor mode and its vectors are never offset from zero.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
[agraf update to apply on top of changed ONE_REG patches]
Signed-off-by: NAvi Kivity <avi@redhat.com>

Decrementers are now properly driven by TCR/TSR, and the guest
has full read/write access to these registers.

The decrementer keeps ticking (and setting the TSR bit) regardless of
whether the interrupts are enabled with TCR.

The decrementer stops at zero, rather than going negative.

Decrementers (and FITs, once implemented) are delivered as
level-triggered interrupts -- dequeued when the TSR bit is cleared, not
on delivery.
Signed-off-by: NLiu Yu <yu.liu@freescale.com>
[scottwood@freescale.com: significant changes]
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This allows additional registers to be accessed by the guest
in PR-mode KVM without trapping.

SPRG4-7 are readable from userspace.  On booke, KVM will sync
these registers when it enters the guest, so that accesses from
guest userspace will work.  The guest kernel, OTOH, must consistently
use either the real registers or the shared area between exits.  This
also applies to the already-paravirted SPRG3.

On non-booke, it's not clear to what extent SPRG4-7 are supported
(they're not architected for book3s, but exist on at least some classic
chips).  They are copied in the get/set regs ioctls, but I do not see any
non-booke emulation.  I also do not see any syncing with real registers
(in PR-mode) including the user-readable SPRG3.  This patch should not
make that situation any worse.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

int_pending was only being lowered if a bit in pending_exceptions
was cleared during exception delivery -- but for interrupts, we clear
it during IACK/TSR emulation.  This caused paravirt for enabling
MSR[EE] to be ineffective.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This prevents us from inappropriately blocking in a KVM_SET_REGS
ioctl -- the MSR[WE] will take effect when the guest is next entered.

It also causes SRR1[WE] to be set when we enter the guest's interrupt
handler, which is what e500 hardware is documented to do.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This function should be called with interrupts disabled, to avoid
a race where an exception is delivered after we check, but the
resched kick is received before we disable interrupts (and thus doesn't
actually trigger the exit code that would recheck exceptions).

booke already does this properly in the lightweight exit case, but
not on initial entry.

For now, move the call of prepare_to_enter into subarch-specific code so
that booke can do the right thing here.  Ideally book3s would do the same
thing, but I'm having a hard time seeing where it does any interrupt
disabling of this sort (plus it has several additional call sites), so
I'm deferring the book3s fix to someone more familiar with that code.
book3s behavior should be unchanged by this patch.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>