The generic KVM code uses SRCU (sleeping RCU) to protect accesses
to the memslots data structures against updates due to userspace
adding, modifying or removing memory slots.  We need to do that too,
both to avoid accessing stale copies of the memslots and to avoid
lockdep warnings.  This therefore adds srcu_read_lock/unlock pairs
around code that accesses and uses memslots.

Since the real-mode handlers for H_ENTER, H_REMOVE and H_BULK_REMOVE
need to access the memslots, and we don't want to call the SRCU code
in real mode (since we have no assurance that it would only access
the linear mapping), we hold the SRCU read lock for the VM while
in the guest.  This does mean that adding or removing memory slots
while some vcpus are executing in the guest will block for up to
two jiffies.  This tradeoff is acceptable since adding/removing
memory slots only happens rarely, while H_ENTER/H_REMOVE/H_BULK_REMOVE
are performance-critical hot paths.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

The current form of DO_KVM macro restricts its use to one call per input
parameter set. This is caused by kvmppc_resume_\intno\()_\srr1 symbol
definition.
Duplicate calls of DO_KVM are required by distinct implementations of
exeption handlers which are delegated at runtime. Use a rare label number
to avoid conflicts with the calling contexts.
Signed-off-by: NMihai Caraman <mihai.caraman@freescale.com>
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>

We need mfdcrx to execute properly on 460 cores.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We need mtdcrx to execute properly on 460 cores.
Signed-off-by: NAlexander Graf <agraf@suse.de>

Patch to access the debug registers (IACx/DACx) using ONE_REG api
was sent earlier. But that missed the respective documentation.

Also corrected the index number referencing in section 4.69
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Since we always mark pages as dirty immediately when mapping them read/write
now, there's no need for the dirty flag in our cache.
Signed-off-by: NAlexander Graf <agraf@suse.de>

Exit traces are a lot easier to read when you don't have to remember
cryptic numbers for guest exit reasons. Symbolify them in our trace
output.
Signed-off-by: NAlexander Graf <agraf@suse.de>

Add support for the MCSR SPR. This only implements the SPR storage
bits, not actual machine checks.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We need to make sure that vcpu->arch.pvr is initialized to a sane value,
so let's just take the host PVR.
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 don't need to do anything when mode is EXITING_GUEST_MODE, because
we essentially are outside of guest mode and did everything it asked
us to do by the time we check it.
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>

When going out of guest mode, indicate that we are in vcpu->mode. That way
requests from other CPUs don't needlessly need to kick us to process them,
because it'll just happen next time we enter the guest.
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>

Now that we use our generic exit helper, we can safely drop our previous
kvm_resched that we used to trigger at the beginning of the exit handler
function.
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>

Now that we have very simple MMU Notifier support for e500 in place,
also add the same simple support to book3s. It gets us one step closer
to actual fast support.
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>

This fixes breakage introduced by the following commit:

  commit 6d2d82627f4f1e96a33664ace494fa363e0495cb
  Author: Liu Yu-B13201 <Yu.Liu@freescale.com>
  Date:   Tue Jul 3 05:48:56 2012 +0000

    PPC: Don't use hardcoded opcode for ePAPR hcall invocation

when a driver that uses ePAPR hypercalls is built as a module.
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This is printed once for every RMA or HPT region that get
preallocated.  If one preallocates hundreds of such regions
(in order to run hundreds of KVM guests), that gets rather
painful, so make it a bit quieter.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Our mapping code assumes that TLB0 entries are always mapped. However, after
calling clear_tlb_refs() this is no longer the case.

Map them dynamically if we find an entry unmapped in TLB0.
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>

Semantically, the "SYNC" cap means that we have mmu notifiers available.
Express this in our #ifdef'ery around the feature, so that we can be sure
we don't miss out on ppc targets when they get their implementation.
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: NLiu Yu <yu.liu@freescale.com>
Signed-off-by: NStuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NStuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Signed-off-by: NStuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Signed-off-by: NLiu Yu <yu.liu@freescale.com>
[varun: 64-bit changes]
Signed-off-by: NVarun Sethi <Varun.Sethi@freescale.com>
Signed-off-by: NStuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

And add a new flag definition in kvm_ppc_pvinfo to indicate
whether the host supports the EV_IDLE hcall.
Signed-off-by: NLiu Yu <yu.liu@freescale.com>
[stuart.yoder@freescale.com: cleanup,fixes for conditions allowing idle]
Signed-off-by: NStuart Yoder <stuart.yoder@freescale.com>
[agraf: fix typo]
Signed-off-by: NAlexander Graf <agraf@suse.de>