Simplify the handling of lazy EE by going directly from fully-enabled
to hard-disabled.  This replaces the lazy_irq_pending() check
(including its misplaced kvm_guest_exit() call).

As suggested by Tiejun Chen, move the interrupt disabling into
kvmppc_prepare_to_enter() rather than have each caller do it.  Also
move the IRQ enabling on heavyweight exit into
kvmppc_prepare_to_enter().
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Rather than calling hard_irq_disable() when we're back in C code
we can just call RECONCILE_IRQ_STATE to soft disable IRQs while
we're already in hard disabled state.

This should be functionally equivalent to the code before, but
cleaner and faster.
Signed-off-by: NTiejun Chen <tiejun.chen@windriver.com>
[agraf: fix comment, commit message]
Signed-off-by: NAlexander Graf <agraf@suse.de>

KVM uses same WIM tlb attributes as the corresponding qemu pte.
For this we now search the linux pte for the requested page and
get these cache caching/coherency attributes from pte.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Reviewed-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Now that we have the vcpu floating-point and vector state stored in
the same type of struct as the main kernel uses, we can load that
state directly from the vcpu struct instead of having extra copies
to/from the thread_struct.  Similarly, when the guest state needs to
be saved, we can have it saved it directly to the vcpu struct by
setting the current->thread.fp_save_area and current->thread.vr_save_area
pointers.  That also means that we don't need to back up and restore
userspace's FP/vector state.  This all makes the code simpler and
faster.

Note that it's not necessary to save or modify current->thread.fpexc_mode,
since nothing in KVM uses or is affected by its value.  Nor is it
necessary to touch used_vr or used_vsr.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This uses struct thread_fp_state and struct thread_vr_state to store
the floating-point, VMX/Altivec and VSX state, rather than flat arrays.
This makes transferring the state to/from the thread_struct simpler
and allows us to unify the get/set_one_reg implementations for the
VSX registers.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This moves the kvmppc_ops callbacks to be a per VM entity. This
enables us to select HV and PR mode when creating a VM. We also
allow both kvm-hv and kvm-pr kernel module to be loaded. To
achieve this we move /dev/kvm ownership to kvm.ko module. Depending on
which KVM mode we select during VM creation we take a reference
count on respective module
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[agraf: fix coding style]
Signed-off-by: NAlexander Graf <agraf@suse.de>

We will use that in the later patch to find the kvm ops handler
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This patch add a new callback kvmppc_ops. This will help us in enabling
both HV and PR KVM together in the same kernel. The actual change to
enable them together is done in the later patch in the series.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[agraf: squash in booke changes]
Signed-off-by: NAlexander Graf <agraf@suse.de>

This patch adds the debug stub support on booke/bookehv.
Now QEMU debug stub can use hw breakpoint, watchpoint and
software breakpoint to debug guest.

This is how we save/restore debug register context when switching
between guest, userspace and kernel user-process:

When QEMU is running
 -> thread->debug_reg == QEMU debug register context.
 -> Kernel will handle switching the debug register on context switch.
 -> no vcpu_load() called

QEMU makes ioctls (except RUN)
 -> This will call vcpu_load()
 -> should not change context.
 -> Some ioctls can change vcpu debug register, context saved in vcpu->debug_regs

QEMU Makes RUN ioctl
 -> Save thread->debug_reg on STACK
 -> Store thread->debug_reg == vcpu->debug_reg
 -> load thread->debug_reg
 -> RUN VCPU ( So thread points to vcpu context )

Context switch happens When VCPU running
 -> makes vcpu_load() should not load any context
 -> kernel loads the vcpu context as thread->debug_regs points to vcpu context.

On heavyweight_exit
 -> Load the context saved on stack in thread->debug_reg

Currently we do not support debug resource emulation to guest,
On debug exception, always exit to user space irrespective of
user space is expecting the debug exception or not. If this is
unexpected exception (breakpoint/watchpoint event not set by
userspace) then let us leave the action on user space. This
is similar to what it was before, only thing is that now we
have proper exit state available to user space.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

For KVM also use the "struct debug_reg" defined in asm/processor.h
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

"ehpriv 1" instruction is used for setting software breakpoints
by user space. This patch adds support to exit to user space
with "run->debug" have relevant information.

As this is the first point we are using run->debug, also defined
the run->debug structure.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This makes the VRSAVE register value for a vcpu accessible through
the GET/SET_ONE_REG interface on Book E systems (in addition to the
existing GET/SET_SREGS interface), for consistency with Book 3S.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This creates new 'thread_fp_state' and 'thread_vr_state' structures
to store FP/VSX state (including FPSCR) and Altivec/VSX state
(including VSCR), and uses them in the thread_struct.  In the
thread_fp_state, the FPRs and VSRs are represented as u64 rather
than double, since we rarely perform floating-point computations
on the values, and this will enable the structures to be used
in KVM code as well.  Similarly FPSCR is now a u64 rather than
a structure of two 32-bit values.

This takes the offsets out of the macros such as SAVE_32FPRS,
REST_32FPRS, etc.  This enables the same macros to be used for normal
and transactional state, enabling us to delete the transactional
versions of the macros.   This also removes the unused do_load_up_fpu
and do_load_up_altivec, which were in fact buggy since they didn't
create large enough stack frames to account for the fact that
load_up_fpu and load_up_altivec are not designed to be called from C
and assume that their caller's stack frame is an interrupt frame.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

kvm_guest_enter() was already called by kvmppc_prepare_to_enter().
Don't call it again.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Currently this is only being done on 64-bit.  Rather than just move it
out of the 64-bit ifdef, move it to kvm_lazy_ee_enable() so that it is
consistent with lazy ee state, and so that we don't track more host
code as interrupts-enabled than necessary.

Rename kvm_lazy_ee_enable() to kvm_fix_ee_before_entry() to reflect
that this function now has a role on 32-bit as well.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Availablity of the doorbell_exception function is guarded by
CONFIG_PPC_DOORBELL. Use the same define to guard our caller
of it.
Signed-off-by: NTiejun Chen <tiejun.chen@windriver.com>
[agraf: improve patch description]
Signed-off-by: NAlexander Graf <agraf@suse.de>

kwmppc_lazy_ee_enable() should be called as late as possible,
or else we get things like WARN_ON(preemptible()) in enable_kernel_fp()
in configurations where preemptible() works.

Note that book3s_pr already waits until just before __kvmppc_vcpu_run
to call kvmppc_lazy_ee_enable().
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

EE is hard-disabled on entry to kvmppc_handle_exit(), so call
hard_irq_disable() so that PACA_IRQ_HARD_DIS is set, and soft_enabled
is unset.

Without this, we get warnings such as arch/powerpc/kernel/time.c:300,
and sometimes host kernel hangs.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

KVM core expects arch code to acquire the srcu lock when calling
gfn_to_memslot and similar functions.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

Enabling this capability connects the vcpu to the designated in-kernel
MPIC.  Using explicit connections between vcpus and irqchips allows
for flexibility, but the main benefit at the moment is that it
simplifies the code -- KVM doesn't need vm-global state to remember
which MPIC object is associated with this vm, and it doesn't need to
care about ordering between irqchip creation and vcpu creation.
Signed-off-by: NScott Wood <scottwood@freescale.com>
[agraf: add stub functions for kvmppc_mpic_{dis,}connect_vcpu]
Signed-off-by: NAlexander Graf <agraf@suse.de>

Hook the MPIC code up to the KVM interfaces, add locking, etc.
Signed-off-by: NScott Wood <scottwood@freescale.com>
[agraf: add stub function for kvmppc_mpic_set_epr, non-booke, 64bit]
Signed-off-by: NAlexander Graf <agraf@suse.de>

Refactor Book3E ONE_REG ioctl implementation to use kvmppc_get_one_reg/
kvmppc_set_one_reg delegation interface introduced by Book3S. This is
necessary for MMU SPRs which are platform specifics.

Get rid of useless case braces in the process.
Signed-off-by: NMihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This allows the exit to user space if emulator request by returning
EMULATE_EXIT_USER. This will be used in subsequent patches in list
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This patch defines the interface parameter for KVM_SET_GUEST_DEBUG
ioctl support. Follow up patches will use this for setting up
hardware breakpoints, watchpoints and software breakpoints.

Also kvm_arch_vcpu_ioctl_set_guest_debug() is brought one level below.
This is because I am not sure what is required for book3s. So this ioctl
behaviour will not change for book3s.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This patch adds the one_reg interface to get the special instruction
to be used for setting software breakpoint from userspace.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Currently kvmppc_core_dequeue_external() takes a struct kvm_interrupt *
argument and does nothing with it, in any of its implementations.
This removes it in order to make things easier for forthcoming
in-kernel interrupt controller emulation code.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

If userspace wants to change some specific bits of TSR
(timer status register) then it uses GET/SET_SREGS ioctl interface.
So the steps will be:
      i)   user-space will make get ioctl,
      ii)  change TSR in userspace
      iii) then make set ioctl.
It can happen that TSR gets changed by kernel after step i) and
before step iii).

To avoid this we have added below one_reg ioctls for oring and clearing
specific bits in TSR. This patch adds one registerface for:
     1) setting specific bit in TSR (timer status register)
     2) clearing specific bit in TSR (timer status register)
     3) setting/getting the TCR register. There are cases where we want to only
        change TCR and not TSR. Although we can uses SREGS without
        KVM_SREGS_E_UPDATE_TSR flag but I think one reg is better. I am open
        if someone feels we should use SREGS only here.
     4) getting/setting TSR register
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This is done so that same function can be called from SREGS and
ONE_REG interface (follow up patch).
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This patch makes the parameter old a const pointer to the old memory
slot and adds a new parameter named change to know the change being
requested: the former is for removing extra copying and the latter is
for cleaning up the code.
Signed-off-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

When the guest triggers an alignment interrupt, we don't handle it properly
today and instead BUG_ON(). This really shouldn't happen.

Instead, we should just pass the interrupt back into the guest so it can deal
with it.
Reported-by: NGao Guanhua-B22826 <B22826@freescale.com>
Tested-by: NGao Guanhua-B22826 <B22826@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Current kvmppc_booke_handlers uses the same macro (KVM_HANDLER) and
all handlers are considered to be the same size. This will not be
the case if we want to use different macros for different handlers.

This patch improves the kvmppc_booke_handler so that it can
support different macros for different handlers.
Signed-off-by: NLiu Yu <yu.liu@freescale.com>
[bharat.bhushan@freescale.com: Substantial changes]
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

We need to be able to read and write the contents of the EPR register
from user space.

This patch implements that logic through the ONE_REG API and declares
its (never implemented) SREGS counterpart as deprecated.
Signed-off-by: NAlexander Graf <agraf@suse.de>

The External Proxy Facility in FSL BookE chips allows the interrupt
controller to automatically acknowledge an interrupt as soon as a
core gets its pending external interrupt delivered.

Today, user space implements the interrupt controller, so we need to
check on it during such a cycle.

This patch implements logic for user space to enable EPR exiting,
disable EPR exiting and EPR exiting itself, so that user space can
acknowledge an interrupt when an external interrupt has successfully
been delivered into the guest vcpu.
Signed-off-by: NAlexander Graf <agraf@suse.de>

When injecting an interrupt into guest context, we usually don't need
to check for requests anymore. At least not until today.

With the introduction of EPR, we will have to create a request when the
guest has successfully accepted an external interrupt though.

So we need to prepare the interrupt delivery to abort guest entry
gracefully. Otherwise we'd delay the EPR request.
Signed-off-by: NAlexander Graf <agraf@suse.de>

Implement ONE_REG interface for EPCR register adding KVM_REG_PPC_EPCR to
the list of ONE_REG PPC supported registers.
Signed-off-by: NMihai Caraman <mihai.caraman@freescale.com>
[agraf: remove HV dependency, use get/put_user]
Signed-off-by: NAlexander Graf <agraf@suse.de>

Add EPCR support in booke mtspr/mfspr emulation. EPCR register is defined only
for 64-bit and HV categories, we will expose it at this point only to 64-bit
virtual processors running on 64-bit HV hosts.
Define a reusable setter function for vcpu's EPCR.
Signed-off-by: NMihai Caraman <mihai.caraman@freescale.com>
[agraf: move HV dependency in the code]
Signed-off-by: NAlexander Graf <agraf@suse.de>

When delivering guest IRQs, update MSR computation mode according to guest
interrupt computation mode found in EPCR.
Signed-off-by: NMihai Caraman <mihai.caraman@freescale.com>
[agraf: remove HV dependency in the code]
Signed-off-by: NAlexander Graf <agraf@suse.de>

Include header file for get_tb() declaration.
Signed-off-by: NMihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

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>