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120 commits

Author SHA1 Message Date
Paul Mackerras
a2932923cc KVM: PPC: Book3S HV: Provide a method for userspace to read and write the HPT
A new ioctl, KVM_PPC_GET_HTAB_FD, returns a file descriptor.  Reads on
this fd return the contents of the HPT (hashed page table), writes
create and/or remove entries in the HPT.  There is a new capability,
KVM_CAP_PPC_HTAB_FD, to indicate the presence of the ioctl.  The ioctl
takes an argument structure with the index of the first HPT entry to
read out and a set of flags.  The flags indicate whether the user is
intending to read or write the HPT, and whether to return all entries
or only the "bolted" entries (those with the bolted bit, 0x10, set in
the first doubleword).

This is intended for use in implementing qemu's savevm/loadvm and for
live migration.  Therefore, on reads, the first pass returns information
about all HPTEs (or all bolted HPTEs).  When the first pass reaches the
end of the HPT, it returns from the read.  Subsequent reads only return
information about HPTEs that have changed since they were last read.
A read that finds no changed HPTEs in the HPT following where the last
read finished will return 0 bytes.

The format of the data provides a simple run-length compression of the
invalid entries.  Each block of data starts with a header that indicates
the index (position in the HPT, which is just an array), the number of
valid entries starting at that index (may be zero), and the number of
invalid entries following those valid entries.  The valid entries, 16
bytes each, follow the header.  The invalid entries are not explicitly
represented.

Signed-off-by: Paul Mackerras <paulus@samba.org>
[agraf: fix documentation]
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-12-06 01:33:57 +01:00
Alexander Graf
0e673fb679 KVM: PPC: Support eventfd
In order to support the generic eventfd infrastructure on PPC, we need
to call into the generic KVM in-kernel device mmio code.

Signed-off-by: Alexander Graf <agraf@suse.de>
2012-12-06 01:33:50 +01:00
Marcelo Tosatti
42897d866b KVM: x86: add kvm_arch_vcpu_postcreate callback, move TSC initialization
TSC initialization will soon make use of online_vcpus.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-11-27 23:29:14 -02:00
Scott Wood
5bd1cf1185 KVM: PPC: set IN_GUEST_MODE before checking requests
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: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:54 +02:00
Paul Mackerras
a47d72f361 KVM: PPC: Book3S HV: Fix updates of vcpu->cpu
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: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:52 +02:00
Paul Mackerras
dfe49dbd1f KVM: PPC: Book3S HV: Handle memory slot deletion and modification correctly
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: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:51 +02:00
Paul Mackerras
a66b48c3a3 KVM: PPC: Move kvm->arch.slot_phys into memslot.arch
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: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:51 +02:00
Bharat Bhushan
f61c94bb99 KVM: PPC: booke: Add watchdog emulation
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: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
[bharat.bhushan@freescale.com: reworked patch]
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
[agraf: adjust to new request framework]
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:47 +02:00
Alexander Graf
7c973a2ebb KVM: PPC: Add return value to core_check_requests
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: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:46 +02:00
Alexander Graf
7ee788556b KVM: PPC: Add return value in prepare_to_enter
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: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:46 +02:00
Alexander Graf
206c2ed7f1 KVM: PPC: Ignore EXITING_GUEST_MODE mode
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: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:46 +02:00
Alexander Graf
3766a4c693 KVM: PPC: Move kvm_guest_enter call into generic code
We need to call kvm_guest_enter in booke and book3s, so move its
call to generic code.

Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:45 +02:00
Alexander Graf
bd2be6836e KVM: PPC: Book3S: PR: Rework irq disabling
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: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:45 +02:00
Alexander Graf
03d25c5bd5 KVM: PPC: Use same kvmppc_prepare_to_enter code for booke and book3s_pr
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: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:42 +02:00
Alexander Graf
f4800b1f4d KVM: PPC: Expose SYNC cap based on mmu notifiers
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: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:39 +02:00
Liu Yu-B13201
9202e07636 KVM: PPC: Add support for ePAPR idle hcall in host kernel
And add a new flag definition in kvm_ppc_pvinfo to indicate
whether the host supports the EV_IDLE hcall.

Signed-off-by: Liu Yu <yu.liu@freescale.com>
[stuart.yoder@freescale.com: cleanup,fixes for conditions allowing idle]
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
[agraf: fix typo]
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:37 +02:00
Stuart Yoder
784bafac79 KVM: PPC: add pvinfo for hcall opcodes on e500mc/e5500
Signed-off-by: Liu Yu <yu.liu@freescale.com>
[stuart: factored this out from idle hcall support in host patch]
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:37 +02:00
Stuart Yoder
fdcf8bd7e7 KVM: PPC: use definitions in epapr header for hcalls
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:36 +02:00
Marcelo Tosatti
2df72e9bc4 KVM: split kvm_arch_flush_shadow
Introducing kvm_arch_flush_shadow_memslot, to invalidate the
translations of a single memory slot.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-09-06 16:37:25 +03:00
Takuya Yoshikawa
d89cc617b9 KVM: Push rmap into kvm_arch_memory_slot
Two reasons:
 - x86 can integrate rmap and rmap_pde and remove heuristics in
   __gfn_to_rmap().
 - Some architectures do not need rmap.

Since rmap is one of the most memory consuming stuff in KVM, ppc'd
better restrict the allocation to Book3S HV.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-08-06 12:47:30 +03:00
Paul Mackerras
32fad281c0 KVM: PPC: Book3S HV: Make the guest hash table size configurable
This adds a new ioctl to enable userspace to control the size of the guest
hashed page table (HPT) and to clear it out when resetting the guest.
The KVM_PPC_ALLOCATE_HTAB ioctl is a VM ioctl and takes as its parameter
a pointer to a u32 containing the desired order of the HPT (log base 2
of the size in bytes), which is updated on successful return to the
actual order of the HPT which was allocated.

There must be no vcpus running at the time of this ioctl.  To enforce
this, we now keep a count of the number of vcpus running in
kvm->arch.vcpus_running.

If the ioctl is called when a HPT has already been allocated, we don't
reallocate the HPT but just clear it out.  We first clear the
kvm->arch.rma_setup_done flag, which has two effects: (a) since we hold
the kvm->lock mutex, it will prevent any vcpus from starting to run until
we're done, and (b) it means that the first vcpu to run after we're done
will re-establish the VRMA if necessary.

If userspace doesn't call this ioctl before running the first vcpu, the
kernel will allocate a default-sized HPT at that point.  We do it then
rather than when creating the VM, as the code did previously, so that
userspace has a chance to do the ioctl if it wants.

When allocating the HPT, we can allocate either from the kernel page
allocator, or from the preallocated pool.  If userspace is asking for
a different size from the preallocated HPTs, we first try to allocate
using the kernel page allocator.  Then we try to allocate from the
preallocated pool, and then if that fails, we try allocating decreasing
sizes from the kernel page allocator, down to the minimum size allowed
(256kB).  Note that the kernel page allocator limits allocations to
1 << CONFIG_FORCE_MAX_ZONEORDER pages, which by default corresponds to
16MB (on 64-bit powerpc, at least).

Signed-off-by: Paul Mackerras <paulus@samba.org>
[agraf: fix module compilation]
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-30 11:43:10 +02:00
Benjamin Herrenschmidt
5b74716eba kvm/powerpc: Add new ioctl to retreive server MMU infos
This is necessary for qemu to be able to pass the right information
to the guest, such as the supported page sizes and corresponding
encodings in the SLB and hash table, which can vary depending
on the processor type, the type of KVM used (PR vs HV) and the
version of KVM

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[agraf: fix compilation on hv, adjust for newer ioctl numbers]
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-06 16:19:12 +02:00
Benjamin Herrenschmidt
f31e65e117 kvm/book3s: Make kernel emulated H_PUT_TCE available for "PR" KVM
There is nothing in the code for emulating TCE tables in the kernel
that prevents it from working on "PR" KVM... other than ifdef's and
location of the code.

This and moves the bulk of the code there to a new file called
book3s_64_vio.c.

This speeds things up a bit on my G5.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[agraf: fix for hv kvm, 32bit, whitespace]
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-06 16:19:11 +02:00
Alexander Graf
bf7ca4bdcb KVM: PPC: rename CONFIG_KVM_E500 -> CONFIG_KVM_E500V2
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: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-04-08 12:54:57 +03:00
Scott Wood
73196cd364 KVM: PPC: e500mc support
Add processor support for e500mc, using hardware virtualization support
(GS-mode).

Current issues include:
 - No support for external proxy (coreint) interrupt mode in the guest.

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: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-04-08 12:54:33 +03:00
Scott Wood
d30f6e4800 KVM: PPC: booke: category E.HV (GS-mode) support
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: Scott Wood <scottwood@freescale.com>
[agraf: remove pt_regs usage]
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-04-08 12:51:19 +03:00
Scott Wood
043cc4d724 KVM: PPC: factor out lpid allocator from book3s_64_mmu_hv
We'll use it on e500mc as well.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-04-08 12:51:02 +03:00
Christoffer Dall
b6d33834bd KVM: Factor out kvm_vcpu_kick to arch-generic code
The kvm_vcpu_kick function performs roughly the same funcitonality on
most all architectures, so we shouldn't have separate copies.

PowerPC keeps a pointer to interchanging waitqueues on the vcpu_arch
structure and to accomodate this special need a
__KVM_HAVE_ARCH_VCPU_GET_WQ define and accompanying function
kvm_arch_vcpu_wq have been defined. For all other architectures this
is a generic inline that just returns &vcpu->wq;

Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-04-08 12:47:47 +03:00
Takuya Yoshikawa
db3fe4eb45 KVM: Introduce kvm_memory_slot::arch and move lpage_info into it
Some members of kvm_memory_slot are not used by every architecture.

This patch is the first step to make this difference clear by
introducing kvm_memory_slot::arch;  lpage_info is moved into it.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-08 14:10:22 +02:00
Alexander Graf
b3c5d3c2a4 KVM: PPC: Rename MMIO register identifiers
We need the KVM_REG namespace for generic register settings now, so
let's rename the existing users to something different, enabling
us to reuse the namespace for more visible interfaces.

While at it, also move these private constants to a private header.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:41 +02:00
Paul Mackerras
31f3438eca KVM: PPC: Move kvm_vcpu_ioctl_[gs]et_one_reg down to platform-specific code
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: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
[agraf update to apply on top of changed ONE_REG patches]
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:41 +02:00
Alexander Graf
1022fc3d3b KVM: PPC: Add support for explicit HIOR setting
Until now, we always set HIOR based on the PVR, but this is just wrong.
Instead, we should be setting HIOR explicitly, so user space can decide
what the initial HIOR value is - just like on real hardware.

We keep the old PVR based way around for backwards compatibility, but
once user space uses the SET_ONE_REG based method, we drop the PVR logic.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:41 +02:00
Alexander Graf
e24ed81fed KVM: PPC: Add generic single register ioctls
Right now we transfer a static struct every time we want to get or set
registers. Unfortunately, over time we realize that there are more of
these than we thought of before and the extensibility and flexibility of
transferring a full struct every time is limited.

So this is a new approach to the problem. With these new ioctls, we can
get and set a single register that is identified by an ID. This allows for
very precise and limited transmittal of data. When we later realize that
it's a better idea to shove over multiple registers at once, we can reuse
most of the infrastructure and simply implement a GET_MANY_REGS / SET_MANY_REGS
interface.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:40 +02:00
Matt Evans
b5434032fc KVM: PPC: Add KVM_CAP_NR_VCPUS and KVM_CAP_MAX_VCPUS
PPC KVM lacks these two capabilities, and as such a userland system must assume
a max of 4 VCPUs (following api.txt).  With these, a userland can determine
a more realistic limit.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:38 +02:00
Matt Evans
03cdab5340 KVM: PPC: Fix vcpu_create dereference before validity check.
Fix usage of vcpu struct before check that it's actually valid.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:38 +02:00
Paul Mackerras
342d3db763 KVM: PPC: Implement MMU notifiers for Book3S HV guests
This adds the infrastructure to enable us to page out pages underneath
a Book3S HV guest, on processors that support virtualized partition
memory, that is, POWER7.  Instead of pinning all the guest's pages,
we now look in the host userspace Linux page tables to find the
mapping for a given guest page.  Then, if the userspace Linux PTE
gets invalidated, kvm_unmap_hva() gets called for that address, and
we replace all the guest HPTEs that refer to that page with absent
HPTEs, i.e. ones with the valid bit clear and the HPTE_V_ABSENT bit
set, which will cause an HDSI when the guest tries to access them.
Finally, the page fault handler is extended to reinstantiate the
guest HPTE when the guest tries to access a page which has been paged
out.

Since we can't intercept the guest DSI and ISI interrupts on PPC970,
we still have to pin all the guest pages on PPC970.  We have a new flag,
kvm->arch.using_mmu_notifiers, that indicates whether we can page
guest pages out.  If it is not set, the MMU notifier callbacks do
nothing and everything operates as before.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:38 +02:00
Paul Mackerras
4e72dbe135 KVM: PPC: Make wakeups work again for Book3S HV guests
When commit f43fdc15fa ("KVM: PPC: booke: Improve timer register
emulation") factored out some code in arch/powerpc/kvm/powerpc.c
into a new helper function, kvm_vcpu_kick(), an error crept in
which causes Book3s HV guest vcpus to stall.  This fixes it.
On POWER7 machines, guest vcpus are grouped together into virtual
CPU cores that share a single waitqueue, so it's important to use
vcpu->arch.wqp rather than &vcpu->wq.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:34 +02:00
Alexander Graf
ae21216bec KVM: PPC: align vcpu_kick with x86
Our vcpu kick implementation differs a bit from x86 which resulted in us not
disabling preemption during the kick. Get it a bit closer to what x86 does.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:30 +02:00
Scott Wood
dfd4d47e9a KVM: PPC: booke: Improve timer register emulation
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: Liu Yu <yu.liu@freescale.com>
[scottwood@freescale.com: significant changes]
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:27 +02:00
Scott Wood
b59049720d KVM: PPC: Paravirtualize SPRG4-7, ESR, PIR, MASn
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: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:26 +02:00
Scott Wood
25051b5a5a KVM: PPC: Move prepare_to_enter call site into subarch code
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: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:26 +02:00
Scott Wood
7e28e60ef9 KVM: PPC: Rename deliver_interrupts to prepare_to_enter
This function also updates paravirt int_pending, so rename it
to be more obvious that this is a collection of checks run prior
to (re)entering a guest.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:25 +02:00
Scott Wood
dc83b8bc02 KVM: PPC: e500: MMU API
This implements a shared-memory API for giving host userspace access to
the guest's TLB.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:24 +02:00
Carsten Otte
5b1c1493af KVM: s390: ucontrol: export SIE control block to user
This patch exports the s390 SIE hardware control block to userspace
via the mapping of the vcpu file descriptor. In order to do so,
a new arch callback named kvm_arch_vcpu_fault  is introduced for all
architectures. It allows to map architecture specific pages.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:19 +02:00
Carsten Otte
e08b963716 KVM: s390: add parameter for KVM_CREATE_VM
This patch introduces a new config option for user controlled kernel
virtual machines. It introduces a parameter to KVM_CREATE_VM that
allows to set bits that alter the capabilities of the newly created
virtual machine.
The parameter is passed to kvm_arch_init_vm for all architectures.
The only valid modifier bit for now is KVM_VM_S390_UCONTROL.
This requires CAP_SYS_ADMIN privileges and creates a user controlled
virtual machine on s390 architectures.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:18 +02:00
Alexander Graf
bb75c627fb Revert "KVM: PPC: Add support for explicit HIOR setting"
This reverts commit a15bd354f0.

It exceeded the padding on the SREGS struct, rendering the ABI
backwards-incompatible.

Conflicts:

	arch/powerpc/kvm/powerpc.c
	include/linux/kvm.h

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-11-17 16:30:25 +02:00
Paul Gortmaker
ead53f22dc powerpc: remove non-required uses of include <linux/module.h>
None of the files touched here are modules, and they are not
exporting any symbols either -- so there is no need to be including
the module.h.  Builds of all the files remains successful.

Even kernel/module.c does not need to include it, since it includes
linux/moduleloader.h instead.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:44 -04:00
Paul Mackerras
19ccb76a19 KVM: PPC: Implement H_CEDE hcall for book3s_hv in real-mode code
With a KVM guest operating in SMT4 mode (i.e. 4 hardware threads per
core), whenever a CPU goes idle, we have to pull all the other
hardware threads in the core out of the guest, because the H_CEDE
hcall is handled in the kernel.  This is inefficient.

This adds code to book3s_hv_rmhandlers.S to handle the H_CEDE hcall
in real mode.  When a guest vcpu does an H_CEDE hcall, we now only
exit to the kernel if all the other vcpus in the same core are also
idle.  Otherwise we mark this vcpu as napping, save state that could
be lost in nap mode (mainly GPRs and FPRs), and execute the nap
instruction.  When the thread wakes up, because of a decrementer or
external interrupt, we come back in at kvm_start_guest (from the
system reset interrupt vector), find the `napping' flag set in the
paca, and go to the resume path.

This has some other ramifications.  First, when starting a core, we
now start all the threads, both those that are immediately runnable and
those that are idle.  This is so that we don't have to pull all the
threads out of the guest when an idle thread gets a decrementer interrupt
and wants to start running.  In fact the idle threads will all start
with the H_CEDE hcall returning; being idle they will just do another
H_CEDE immediately and go to nap mode.

This required some changes to kvmppc_run_core() and kvmppc_run_vcpu().
These functions have been restructured to make them simpler and clearer.
We introduce a level of indirection in the wait queue that gets woken
when external and decrementer interrupts get generated for a vcpu, so
that we can have the 4 vcpus in a vcore using the same wait queue.
We need this because the 4 vcpus are being handled by one thread.

Secondly, when we need to exit from the guest to the kernel, we now
have to generate an IPI for any napping threads, because an HDEC
interrupt doesn't wake up a napping thread.

Thirdly, we now need to be able to handle virtual external interrupts
and decrementer interrupts becoming pending while a thread is napping,
and deliver those interrupts to the guest when the thread wakes.
This is done in kvmppc_cede_reentry, just before fast_guest_return.

Finally, since we are not using the generic kvm_vcpu_block for book3s_hv,
and hence not calling kvm_arch_vcpu_runnable, we can remove the #ifdef
from kvm_arch_vcpu_runnable.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25 19:52:30 +03:00
Alexander Graf
af8f38b349 KVM: PPC: Add sanity checking to vcpu_run
There are multiple features in PowerPC KVM that can now be enabled
depending on the user's wishes. Some of the combinations don't make
sense or don't work though.

So this patch adds a way to check if the executing environment would
actually be able to run the guest properly. It also adds sanity
checks if PVR is set (should always be true given the current code
flow), if PAPR is only used with book3s_64 where it works and that
HV KVM is only used in PAPR mode.

Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25 19:52:27 +03:00
Alexander Graf
930b412a00 KVM: PPC: Enable the PAPR CAP for Book3S
Now that Book3S PV mode can also run PAPR guests, we can add a PAPR cap and
enable it for all Book3S targets. Enabling that CAP switches KVM into PAPR
mode.

Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25 19:52:26 +03:00