Commit Graph
100 Commits
Author SHA1 Message Date
Alexander Graf 29d03158f9 KVM: PPC: Remove prog_flags
Commit c8f729d408 (KVM: PPC: Deliver program interrupts right away instead
of queueing them) made away with all users of prog_flags, so we can just
remove it from the headers.

Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:17:00 +03:00
Alexander Graf a22a2daccf KVM: PPC: Resolve real-mode handlers through function exports
Up until now, Book3S KVM had variables stored in the kernel that a kernel module
or the kvm code in the kernel could read from to figure out where some real mode
helper functions are located.

This is all unnecessary. The high bits of the EA get ignore in real mode, so we
can just use the pointer as is. Also, it's a lot easier on relocations when we
use the normal way of resolving the address to a function, instead of jumping
through hoops.

This patch fixes compilation with CONFIG_RELOCATABLE=y.

Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:29 +03:00
Alexander Graf 1dda606c5f KVM: Add compat ioctl for KVM_SET_SIGNAL_MASK
KVM has an ioctl to define which signal mask should be used while running
inside VCPU_RUN. At least for big endian systems, this mask is different
on 32-bit and 64-bit systems (though the size is identical).

Add a compat wrapper that converts the mask to whatever the kernel accepts,
allowing 32-bit kvm user space to set signal masks.

This patch fixes qemu with --enable-io-thread on ppc64 hosts when running
32-bit user land.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-12 13:16:17 +03:00
Alexander Graf 27923eb19c KVM: PPC: Fix compile warning
KVM compilation fails with the following warning:

include/linux/kvm_host.h: In function 'kvm_irq_routing_update':
include/linux/kvm_host.h:679:2: error: 'struct kvm' has no member named 'irq_routing'

That function is only used and reasonable to have on systems that implement
an in-kernel interrupt chip. PPC doesn't.

Fix by #ifdef'ing it out when no irqchip is available.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:29:42 +02:00
Alexander Graf 26e673c300 KVM: PPC: Move of include to __KERNEL__ section
We have to protect the include for linux/of.h by __KERNEL__ so it doesn't
accidently get referenced outside.

This patch fixes this and makes the tree compile again.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:23 +02:00
Alexander Graf d1e87c7ee6 KVM: PPC: Add documentation for magic page enhancements
This documents how to detect additional features inside the magic
page when a guest maps it.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:22 +02:00
Alexander Graf 344941beb9 KVM: PPC: Fix compile error in e500_tlb.c
The e500_tlb.c file didn't compile for me due to the following error:

arch/powerpc/kvm/e500_tlb.c: In function ‘kvmppc_e500_shadow_map’:
arch/powerpc/kvm/e500_tlb.c:300: error: format ‘%lx’ expects type ‘long unsigned int’, but argument 2 has type ‘gfn_t’

So let's explicitly cast the argument to make printk happy.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:22 +02:00
Alexander Graf 6f7a2bd41f KVM: PPC: Document KVM_INTERRUPT ioctl
This adds some documentation for the KVM_INTERRUPT special cases that
PowerPC now implements.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:20 +02:00
Alexander Graf c5335f1765 KVM: PPC: Implement level interrupts for BookE
BookE also wants to support level based interrupts, so let's implement
all the necessary logic there. We need to trick a bit here because the
irqprios are 1:1 assigned to architecture defined values. But since there
is some space left there, we can just pick a random one and move it later
on - it's internal anyways.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:20 +02:00
Alexander Graf 7b4203e8cb KVM: PPC: Expose level based interrupt cap
Now that we have all the level interrupt magic in place, let's
expose the capability to user space, so it can make use of it!

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:19 +02:00
Alexander Graf 17bd158006 KVM: PPC: Implement Level interrupts on Book3S
The current interrupt logic is just completely broken. We get a notification
from user space, telling us that an interrupt is there. But then user space
expects us that we just acknowledge an interrupt once we deliver it to the
guest.

This is not how real hardware works though. On real hardware, the interrupt
controller pulls the external interrupt line until it gets notified that the
interrupt was received.

So in reality we have two events: pulling and letting go of the interrupt line.

To maintain backwards compatibility, I added a new request for the pulling
part. The letting go part was implemented earlier already.

With this in place, we can now finally start guests that do not randomly stall
and stop to work at random times.

This patch implements above logic for Book3S.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:19 +02:00
Alexander Graf 591bd8e7b4 KVM: PPC: Enable napping only for Book3s_64
Before I incorrectly enabled napping also for BookE, which would result in
needless dcache flushes. Since we only need to force enable napping on
Book3s_64 because it doesn't go into MSR_POW otherwise, we can just #ifdef
that code to this particular platform.

Reported-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:19 +02:00
Alexander Graf 296c19d0b4 KVM: PPC: Don't put MSR_POW in MSR
On Book3S a mtmsr with the MSR_POW bit set indicates that the OS is in
idle and only needs to be waked up on the next interrupt.

Now, unfortunately we let that bit slip into the stored MSR value which
is not what the real CPU does, so that we ended up executing code like
this:

	r = mfmsr();
	/* r containts MSR_POW */
	mtmsr(r | MSR_EE);

This obviously breaks, as we're going into idle mode in code sections that
don't expect to be idling.

This patch masks MSR_POW out of the stored MSR value on wakeup, making
guests happy again.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:16 +02:00
Alexander Graf 8b6db3bc96 KVM: PPC: Implement correct SID mapping on Book3s_32
Up until now we were doing segment mappings wrong on Book3s_32. For Book3s_64
we were using a trick where we know that a single mmu_context gives us 16 bits
of context ids.

The mm system on Book3s_32 instead uses a clever algorithm to distribute VSIDs
across the available range, so a context id really only gives us 16 available
VSIDs.

To keep at least a few guest processes in the SID shadow, let's map a number of
contexts that we can use as VSID pool. This makes the code be actually correct
and shouldn't hurt performance too much.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:15 +02:00
Alexander Graf ad0873763a KVM: PPC: Force enable nap on KVM
There are some heuristics in the PPC power management code that try to find
out if the particular hardware we're running on supports proper power management
or just hangs the machine when going into nap mode.

Since we know that KVM is safe with nap, let's force enable it in the PV code
once we're certain that we are on a KVM VM.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:15 +02:00
Alexander Graf df08bd1026 KVM: PPC: Make PV mtmsrd L=1 work with r30 and r31
We had an arbitrary limitation in mtmsrd L=1 that kept us from using r30 and
r31 as input registers. Let's get rid of that and get more potential speedups!

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:14 +02:00
Alexander Graf 9ee18b1e08 KVM: PPC: Update int_pending also on dequeue
When having a decrementor interrupt pending, the dequeuing happens manually
through an mtdec instruction. This instruction simply calls dequeue on that
interrupt, so the int_pending hint doesn't get updated.

This patch enables updating the int_pending hint also on dequeue, thus
correctly enabling guests to stay in guest contexts more often.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:14 +02:00
Alexander Graf 512ba59ed9 KVM: PPC: Make PV mtmsr work with r30 and r31
So far we've been restricting ourselves to r0-r29 as registers an mtmsr
instruction could use. This was bad, as there are some code paths in
Linux actually using r30.

So let's instead handle all registers gracefully and get rid of that
stupid limitation

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:13 +02:00
Alexander Graf cbe487fac7 KVM: PPC: Add mtsrin PV code
This is the guest side of the mtsr acceleration. Using this a guest can now
call mtsrin with almost no overhead as long as it ensures that it only uses
it with (MSR_IR|MSR_DR) == 0. Linux does that, so we're good.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:12 +02:00
Alexander Graf df1bfa25d8 KVM: PPC: Put segment registers in shared page
Now that the actual mtsr doesn't do anything anymore, we can move the sr
contents over to the shared page, so a guest can directly read and write
its sr contents from guest context.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:11 +02:00
Alexander Graf 8e8651783f KVM: PPC: Interpret SR registers on demand
Right now we're examining the contents of Book3s_32's segment registers when
the register is written and put the interpreted contents into a struct.

There are two reasons this is bad. For starters, the struct has worse real-time
performance, as it occupies more ram. But the more important part is that with
segment registers being interpreted from their raw values, we can put them in
the shared page, allowing guests to mess with them directly.

This patch makes the internal representation of SRs be u32s.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:11 +02:00
Alexander Graf c1c88e2fa1 KVM: PPC: Move BAT handling code into spr handler
The current approach duplicates the spr->bat finding logic and makes it harder
to reuse the actually used variables. So let's move everything down to the spr
handler.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:10 +02:00
Alexander Graf 7508e16c9f KVM: PPC: Add feature bitmap for magic page
We will soon add SR PV support to the shared page, so we need some
infrastructure that allows the guest to query for features KVM exports.

This patch adds a second return value to the magic mapping that
indicated to the guest which features are available.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:09 +02:00
Alexander Graf cb24c50826 KVM: PPC: Remove unused define
The define VSID_ALL is unused. Let's remove it.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:08 +02:00
Alexander Graf b9877ce299 KVM: PPC: Revert "KVM: PPC: Use kernel hash function"
It turns out the in-kernel hash function is sub-optimal for our subtle
hash inputs where every bit is significant. So let's revert to the original
hash functions.

This reverts commit 05340ab4f9a6626f7a2e8f9fe5397c61d494f445.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:08 +02:00
Alexander Graf 928d78be54 KVM: PPC: Move slb debugging to tracepoints
This patch moves debugging printks for shadow SLB debugging over to tracepoints.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:07 +02:00
Alexander Graf e7c1d14e3b KVM: PPC: Make invalidation code more reliable
There is a race condition in the pte invalidation code path where we can't
be sure if a pte was invalidated already. So let's move the spin lock around
to get rid of the race.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:06 +02:00
Alexander Graf 2e602847d9 KVM: PPC: Don't flush PTEs on NX/RO hit
When hitting a no-execute or read-only data/inst storage interrupt we were
flushing the respective PTE so we're sure it gets properly overwritten next.

According to the spec, this is unnecessary though. The guest issues a tlbie
anyways, so we're safe to just keep the PTE around and have it manually removed
from the guest, saving us a flush.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:06 +02:00
Alexander Graf 4cb6b7ea0c KVM: PPC: Preload magic page when in kernel mode
When the guest jumps into kernel mode and has the magic page mapped, theres a
very high chance that it will also use it. So let's detect that scenario and
map the segment accordingly.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:05 +02:00
Alexander Graf c60b4cf701 KVM: PPC: Add tracepoints for generic spte flushes
The different ways of flusing shadow ptes have their own debug prints which use
stupid old printk.

Let's move them to tracepoints, making them easier available, faster and
possible to activate on demand

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:04 +02:00
Alexander Graf c22c31963b KVM: PPC: Fix sid map search after flush
After a flush the sid map contained lots of entries with 0 for their gvsid and
hvsid value. Unfortunately, 0 can be a real value the guest searches for when
looking up a vsid so it would incorrectly find the host's 0 hvsid mapping which
doesn't belong to our sid space.

So let's also check for the valid bit that indicated that the sid we're
looking at actually contains useful data.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:03 +02:00
Alexander Graf 8696ee4312 KVM: PPC: Move pte invalidate debug code to tracepoint
This patch moves the SPTE flush debug printk over to tracepoints.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:03 +02:00
Alexander Graf 4c4eea7769 KVM: PPC: Add tracepoint for generic mmu map
This patch moves the generic mmu map debugging over to tracepoints.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:02 +02:00
Alexander Graf 82fdee7bce KVM: PPC: Move book3s_64 mmu map debug print to trace point
This patch moves Book3s MMU debugging over to tracepoints.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:01 +02:00
Alexander Graf bed1ed9860 KVM: PPC: Move EXIT_DEBUG partially to tracepoints
We have a debug printk on every exit that is usually #ifdef'ed out. Using
tracepoints makes a lot more sense here though, as they can be dynamically
enabled.

This patch converts the most commonly used debug printks of EXIT_DEBUG to
tracepoints.

Signed-off-by: Alexander Graf <agraf@suse.de>
2010-10-24 10:52:00 +02:00
Alexander Graf 989044ee0f KVM: PPC: Fix CONFIG_KVM_GUEST && !CONFIG_KVM case
When CONFIG_KVM_GUEST is selected, but CONFIG_KVM is not, we were missing
some defines in asm-offsets.c and included too many headers at other places.

This patch makes above configuration work.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:51:44 +02:00
Alexander Graf a3c321c6e2 KVM: S390: Export kvm_virtio.h
As suggested by Christian, we should expose headers to user space with
information that might be valuable there. The s390 virtio interface is
one of those cases. It defines an ABI between hypervisor and guest, so
it should be exposed to user space.

Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:51:30 +02:00
Alexander Graf cefa33e2f8 KVM: S390: Add virtio hotplug add support
The one big missing feature in s390-virtio was hotplugging. This is no more.
This patch implements hotplug add support, so you can on the fly add new devices
in the guest.

Keep in mind that this needs a patch for qemu to actually leverage the
functionality.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:51:29 +02:00
Alexander Graf fc678d67fe KVM: S390: take a full byte as ext_param indicator
Currenty the ext_param field only distinguishes between "config change" and
"vring interrupt". We can do a lot more with it though, so let's enable a
full byte of possible values and constants to #defines while at it.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:51:29 +02:00
Alexander Graf a58ddea556 KVM: PPC: Move KVM trampolines before __end_interrupts
When using a relocatable kernel we need to make sure that the trampline code
and the interrupt handlers are both copied to low memory. The only way to do
this reliably is to put them in the copied section.

This patch should make relocated kernels work with KVM.

KVM-Stable-Tag
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:59 +02:00
Alexander Graf 2b05d71fef KVM: PPC: Make long relocations be ulong
On Book3S KVM we directly expose some asm pointers to C code as
variables. These need to be relocated and thus break on relocatable
kernels.

To make sure we can at least build, let's mark them as long instead
of u32 where 64bit relocations don't work.

This fixes the following build error:

WARNING: 2 bad relocations^M
> c000000000008590 R_PPC64_ADDR32    .text+0x4000000000008460^M
> c000000000008594 R_PPC64_ADDR32    .text+0x4000000000008598^M

Please keep in mind that actually using KVM on a relocated kernel
might still break. This only fixes the compile problem.

Reported-by: Subrata Modak <subrata@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:59 +02:00
Alexander Graf 0e67790387 KVM: PPC: Use MSR_DR for external load_up
Book3S_32 requires MSR_DR to be disabled during load_up_xxx while on Book3S_64
it's supposed to be enabled. I misread the code and disabled it in both cases,
potentially breaking the PS3 which has a really small RMA.

This patch makes KVM work on the PS3 again.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:59 +02:00
Alexander Graf 2d27fc5eac KVM: PPC: Add book3s_32 tlbie flush acceleration
On Book3s_32 the tlbie instruction flushed effective addresses by the mask
0x0ffff000. This is pretty hard to reflect with a hash that hashes ~0xfff, so
to speed up that target we should also keep a special hash around for it.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:58 +02:00
Alexander Graf 2e0908afaf KVM: PPC: RCU'ify the Book3s MMU
So far we've been running all code without locking of any sort. This wasn't
really an issue because I didn't see any parallel access to the shadow MMU
code coming.

But then I started to implement dirty bitmapping to MOL which has the video
code in its own thread, so suddenly we had the dirty bitmap code run in
parallel to the shadow mmu code. And with that came trouble.

So I went ahead and made the MMU modifying functions as parallelizable as
I could think of. I hope I didn't screw up too much RCU logic :-). If you
know your way around RCU and locking and what needs to be done when, please
take a look at this patch.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:58 +02:00
Alexander Graf 5302104235 KVM: PPC: Book3S_32 MMU debug compile fixes
Due to previous changes, the Book3S_32 guest MMU code didn't compile properly
when enabling debugging.

This patch repairs the broken code paths, making it possible to define DEBUG_MMU
and friends again.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:58 +02:00
Alexander Graf 15711e9c92 KVM: PPC: Add get_pvinfo interface to query hypercall instructions
We need to tell the guest the opcodes that make up a hypercall through
interfaces that are controlled by userspace. So we need to add a call
for userspace to allow it to query those opcodes so it can pass them
on.

This is required because the hypercall opcodes can change based on
the hypervisor conditions. If we're running in hardware accelerated
hypervisor mode, a hypercall looks different from when we're running
without hardware acceleration.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:57 +02:00
Alexander Graf d7d3c2ea99 KVM: PPC: Add Documentation about PV interface
We just introduced a new PV interface that screams for documentation. So here
it is - a shiny new and awesome text file describing the internal works of
the PPC KVM paravirtual interface.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:57 +02:00
Alexander Graf 644bfa013f KVM: PPC: PV wrteei
On BookE the preferred way to write the EE bit is the wrteei instruction. It
already encodes the EE bit in the instruction.

So in order to get BookE some speedups as well, let's also PV'nize thati
instruction.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:57 +02:00
Alexander Graf 7810927760 KVM: PPC: PV mtmsrd L=0 and mtmsr
There is also a form of mtmsr where all bits need to be addressed. While the
PPC64 Linux kernel behaves resonably well here, on PPC32 we do not have an
L=1 form. It does mtmsr even for simple things like only changing EE.

So we need to hook into that one as well and check for a mask of bits that we
deem safe to change from within guest context.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:56 +02:00
Alexander Graf 819a63dc79 KVM: PPC: PV mtmsrd L=1
The PowerPC ISA has a special instruction for mtmsr that only changes the EE
and RI bits, namely the L=1 form.

Since that one is reasonably often occuring and simple to implement, let's
go with this first. Writing EE=0 is always just a store. Doing EE=1 also
requires us to check for pending interrupts and if necessary exit back to the
hypervisor.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:56 +02:00
Alexander Graf 92234722ed KVM: PPC: PV assembler helpers
When we hook an instruction we need to make sure we don't clobber any of
the registers at that point. So we write them out to scratch space in the
magic page. To make sure we don't fall into a race with another piece of
hooked code, we need to disable interrupts.

To make the later patches and code in general easier readable, let's introduce
a set of defines that save and restore r30, r31 and cr. Let's also define some
helpers to read the lower 32 bits of a 64 bit field on 32 bit systems.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:55 +02:00
Alexander Graf 71ee8e34fe KVM: PPC: Introduce branch patching helper
We will need to patch several instruction streams over to a different
code path, so we need a way to patch a single instruction with a branch
somewhere else.

This patch adds a helper to facilitate this patching.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:54 +02:00
Alexander Graf 2d4f567103 KVM: PPC: Introduce kvm_tmp framework
We will soon require more sophisticated methods to replace single instructions
with multiple instructions. We do that by branching to a memory region where we
write replacement code for the instruction to.

This region needs to be within 32 MB of the patched instruction though, because
that's the furthest we can jump with immediate branches.

So we keep 1MB of free space around in bss. After we're done initing we can just
tell the mm system that the unused pages are free, but until then we have enough
space to fit all our code in.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:54 +02:00
Alexander Graf d1290b15e7 KVM: PPC: PV tlbsync to nop
With our current MMU scheme we don't need to know about the tlbsync instruction.
So we can just nop it out.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:53 +02:00
Alexander Graf d1293c9275 KVM: PPC: PV instructions to loads and stores
Some instructions can simply be replaced by load and store instructions to
or from the magic page.

This patch replaces often called instructions that fall into the above category.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:52 +02:00
Alexander Graf 73a1810982 KVM: PPC: KVM PV guest stubs
We will soon start and replace instructions from the text section with
other, paravirtualized versions. To ease the readability of those patches
I split out the generic looping and magic page mapping code out.

This patch still only contains stubs. But at least it loops through the
text section :).

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:51 +02:00
Alexander Graf d17051cb8d KVM: PPC: Generic KVM PV guest support
We have all the hypervisor pieces in place now, but the guest parts are still
missing.

This patch implements basic awareness of KVM when running Linux as guest. It
doesn't do anything with it yet though.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:50 +02:00
Alexander Graf ba49296236 KVM: Move kvm_guest_init out of generic code
Currently x86 is the only architecture that uses kvm_guest_init(). With
PowerPC we're getting a second user, but the signature is different there
and we don't need to export it, as it uses the normal kernel init framework.

So let's move the x86 specific definition of that function over to the x86
specfic header file.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:49 +02:00
Alexander Graf 5fc87407b5 KVM: PPC: Expose magic page support to guest
Now that we have the shared page in place and the MMU code knows about
the magic page, we can expose that capability to the guest!

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:49 +02:00
Alexander Graf e8508940a8 KVM: PPC: Magic Page Book3s support
We need to override EA as well as PA lookups for the magic page. When the guest
tells us to project it, the magic page overrides any guest mappings.

In order to reflect that, we need to hook into all the MMU layers of KVM to
force map the magic page if necessary.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:48 +02:00
Alexander Graf beb03f14da KVM: PPC: First magic page steps
We will be introducing a method to project the shared page in guest context.
As soon as we're talking about this coupling, the shared page is colled magic
page.

This patch introduces simple defines, so the follow-up patches are easier to
read.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:46 +02:00
Alexander Graf 28e83b4fa7 KVM: PPC: Make PAM a define
On PowerPC it's very normal to not support all of the physical RAM in real mode.
To check if we're matching on the shared page or not, we need to know the limits
so we can restrain ourselves to that range.

So let's make it a define instead of open-coding it. And while at it, let's also
increase it.

Signed-off-by: Alexander Graf <agraf@suse.de>

v2 -> v3:

  - RMO -> PAM (non-magic page)
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:46 +02:00
Alexander Graf 90bba35887 KVM: PPC: Tell guest about pending interrupts
When the guest turns on interrupts again, it needs to know if we have an
interrupt pending for it. Because if so, it should rather get out of guest
context and get the interrupt.

So we introduce a new field in the shared page that we use to tell the guest
that there's a pending interrupt lying around.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:46 +02:00
Alexander Graf fad93fe1d4 KVM: PPC: Add PV guest scratch registers
While running in hooked code we need to store register contents out because
we must not clobber any registers.

So let's add some fields to the shared page we can just happily write to.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:46 +02:00
Alexander Graf 5c6cedf488 KVM: PPC: Add PV guest critical sections
When running in hooked code we need a way to disable interrupts without
clobbering any interrupts or exiting out to the hypervisor.

To achieve this, we have an additional critical field in the shared page. If
that field is equal to the r1 register of the guest, it tells the hypervisor
that we're in such a critical section and thus may not receive any interrupts.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:46 +02:00
Alexander Graf 2a342ed577 KVM: PPC: Implement hypervisor interface
To communicate with KVM directly we need to plumb some sort of interface
between the guest and KVM. Usually those interfaces use hypercalls.

This hypercall implementation is described in the last patch of the series
in a special documentation file. Please read that for further information.

This patch implements stubs to handle KVM PPC hypercalls on the host and
guest side alike.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:45 +02:00
Alexander Graf a73a9599e0 KVM: PPC: Convert SPRG[0-4] to shared page
When in kernel mode there are 4 additional registers available that are
simple data storage. Instead of exiting to the hypervisor to read and
write those, we can just share them with the guest using the page.

This patch converts all users of the current field to the shared page.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:45 +02:00
Alexander Graf de7906c36c KVM: PPC: Convert SRR0 and SRR1 to shared page
The SRR0 and SRR1 registers contain cached values of the PC and MSR
respectively. They get written to by the hypervisor when an interrupt
occurs or directly by the kernel. They are also used to tell the rfi(d)
instruction where to jump to.

Because it only gets touched on defined events that, it's very simple to
share with the guest. Hypervisor and guest both have full r/w access.

This patch converts all users of the current field to the shared page.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:45 +02:00
Alexander Graf 5e030186df KVM: PPC: Convert DAR to shared page.
The DAR register contains the address a data page fault occured at. This
register behaves pretty much like a simple data storage register that gets
written to on data faults. There is no hypervisor interaction required on
read or write.

This patch converts all users of the current field to the shared page.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:45 +02:00
Alexander Graf d562de48de KVM: PPC: Convert DSISR to shared page
The DSISR register contains information about a data page fault. It is fully
read/write from inside the guest context and we don't need to worry about
interacting based on writes of this register.

This patch converts all users of the current field to the shared page.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:44 +02:00
Alexander Graf 666e7252a1 KVM: PPC: Convert MSR to shared page
One of the most obvious registers to share with the guest directly is the
MSR. The MSR contains the "interrupts enabled" flag which the guest has to
toggle in critical sections.

So in order to bring the overhead of interrupt en- and disabling down, let's
put msr into the shared page. Keep in mind that even though you can fully read
its contents, writing to it doesn't always update all state. There are a few
safe fields that don't require hypervisor interaction. See the documentation
for a list of MSR bits that are safe to be set from inside the guest.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:43 +02:00
Alexander Graf 96bc451a15 KVM: PPC: Introduce shared page
For transparent variable sharing between the hypervisor and guest, I introduce
a shared page. This shared page will contain all the registers the guest can
read and write safely without exiting guest context.

This patch only implements the stubs required for the basic structure of the
shared page. The actual register moving follows.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:42 +02:00
Alexander Graf 6d4f2fb086 powerpc/85xx: Fix compilation of mpc85xx_mds.c
Commit 99d8238f berobbed the for_each loop of its iterator! Let's be
nice and give it back, so it compiles for us.

CC: Anton Vorontsov <avorontsov@mvista.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2010-08-31 11:36:04 -05:00
Alexander Graf fef093bec0 KVM: PPC: Make use of hash based Shadow MMU
We just introduced generic functions to handle shadow pages on PPC.
This patch makes the respective backends make use of them, getting
rid of a lot of duplicate code along the way.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:47:28 +03:00
Alexander Graf 7741909bf1 KVM: PPC: Add generic hpte management functions
Currently the shadow paging code keeps an array of entries it knows about.
Whenever the guest invalidates an entry, we loop through that entry,
trying to invalidate matching parts.

While this is a really simple implementation, it is probably the most
ineffective one possible. So instead, let's keep an array of lists around
that are indexed by a hash. This way each PTE can be added by 4 list_add,
removed by 4 list_del invocations and the search only needs to loop through
entries that share the same hash.

This patch implements said lookup and exports generic functions that both
the 32-bit and 64-bit backend can use.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:47:27 +03:00
Alexander Graf 4d29bdbf12 KVM: PPC: Make BAT only guest segments work
When a guest sets its SR entry to invalid, we may still find a
corresponding entry in a BAT. So we need to make sure we're not
faulting on invalid SR entries, but instead just claim them to be
BAT resolved.

This resolves breakage experienced when using libogc based guests.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:47:14 +03:00
Alexander Graf 3b249157c0 KVM: PPC: Use kernel hash function
The linux kernel already provides a hash function. Let's reuse that
instead of reinventing the wheel!

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:47:13 +03:00
Alexander Graf a576f7a294 KVM: PPC: Remove obsolete kvmppc_mmu_find_pte
Initially we had to search for pte entries to invalidate them. Since
the logic has improved since then, we can just get rid of the search
function.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:47:12 +03:00
Alexander Graf b83d4a9cfc KVM: PPC: Enable native paired singles
When we're on a paired single capable host, we can just always enable
paired singles and expose them to the guest directly.

This approach breaks when multiple VMs run and access PS concurrently,
but this should suffice until we get a proper framework for it in Linux.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:08 +03:00
Alexander Graf 251585b5d0 KVM: PPC: Find HTAB ourselves
For KVM we need to find the location of the HTAB. We can either rely
on internal data structures of the kernel or ask the hardware.

Ben issued complaints about the internal data structure method, so
let's switch it to our own inquiry of the HTAB. Now we're fully
independend :-).

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:07 +03:00
Alexander Graf 5156f274bb KVM: PPC: Fix Book3S_64 Host MMU debug output
We have some debug output in Book3S_64. Some of that was invalid though,
partially not even compiling because it accessed incorrect variables.

So let's fix that up, making debugging more fun again.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:05 +03:00
Alexander Graf 6355644190 KVM: PPC: Set VSID_PR also for Book3S_64
Book3S_64 didn't set VSID_PR when we're in PR=1. This lead to pretty bad
behavior when searching for the shadow segment, as part of the code relied
on VSID_PR being set.

This patch fixes booting Book3S_64 guests.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:03 +03:00
Alexander Graf ac21467182 KVM: PPC: Be more informative on BUG
We have a condition in the ppc64 host mmu code that should never occur.
Unfortunately, it just did happen to me and I was rather puzzled on why,
because BUG_ON doesn't tell me anything useful.

So let's add some more debug output in case this goes wrong. Also change
BUG to WARN, since I don't want to reboot every time I mess something up.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:02 +03:00
Alexander Graf 6fc5582580 KVM: PPC: Make Alignment interrupts work again
In the process of merging Book3S_32 and 64 I somehow ended up having the
alignment interrupt handler take last_inst, but the fetching code not
fetching it. So we ended up with stale last_inst values.

Let's just enable last_inst fetching for alignment interrupts too.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:00 +03:00
Alexander Graf f7bc74e1c3 KVM: PPC: Improve split mode
When in split mode, instruction relocation and data relocation are not equal.

So far we implemented this mode by reserving a special pseudo-VSID for the
two cases and flushing all PTEs when going into split mode, which is slow.

Unfortunately 32bit Linux and Mac OS X use split mode extensively. So to not
slow down things too much, I came up with a different idea: Mark the split
mode with a bit in the VSID and then treat it like any other segment.

This means we can just flush the shadow segment cache, but keep the PTEs
intact. I verified that this works with ppc32 Linux and Mac OS X 10.4
guests and does speed them up.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:58 +03:00
Alexander Graf 7fdaec997c KVM: PPC: Make Performance Counters work
When we get a performance counter interrupt we need to route it on to the
Linux handler after we got out of the guest context. We also need to tell
our handling code that this particular interrupt doesn't need treatment.

So let's add those two bits in, making perf work while having a KVM guest
running.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:57 +03:00
Alexander Graf af7b4d104b KVM: PPC: Convert u64 -> ulong
There are some pieces in the code that I overlooked that still use
u64s instead of longs. This slows down 32 bit hosts unnecessarily, so
let's just move them to ulong.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:55 +03:00
Alexander Graf 4f84139037 KVM: PPC: Enable Book3S_32 KVM building
Now that we have all the bits and pieces in place, let's enable building
of the Book3S_32 target.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:54 +03:00
Alexander Graf dd84c21748 KVM: PPC: Add KVM intercept handlers
When an interrupt occurs we don't know yet if we're in guest context or
in host context. When in guest context, KVM needs to handle it.

So let's pull the same trick we did on Book3S_64: Just add a macro to
determine if we're in guest context or not and if so jump on to KVM code.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:52 +03:00
Alexander Graf ada7ba17b4 KVM: PPC: Check max IRQ prio
We have a define on what the highest bit of IRQ priorities is. So we can
just as well use it in the bit checking code and avoid invalid IRQ values
to be triggered.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:51 +03:00
Alexander Graf 218d169c4c PPC: Export SWITCH_FRAME_SIZE
We need the SWITCH_FRAME_SIZE define on Book3S_32 now too.
So let's export it unconditionally.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:49 +03:00
Alexander Graf be85669886 KVM: PPC: Export MMU variables
Our shadow MMU code needs to know where the HTAB is located and how
big it is. So we need some variables from the kernel exported to
module space if KVM is built as a module.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:48 +03:00
Alexander Graf 07b0907db1 KVM: PPC: Add Book3S compatibility code
Some code we had so far required defines and had code that was completely
Book3S_64 specific. Since we now opened book3s.c to Book3S_32 too, we need
to take care of these pieces.

So let's add some minor code where it makes sense to not go the Book3S_64
code paths and add compat defines on others.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:46 +03:00
Alexander Graf 61db97cc1e KVM: PPC: Emulate segment fault
Book3S_32 doesn't know about segment faults. It only knows about page faults.
So in order to know that we didn't map a segment, we need to fake segment
faults.

We do this by setting invalid segment registers to an invalid VSID and then
check for that VSID on normal page faults.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:45 +03:00
Alexander Graf 97e492558f KVM: PPC: Add SVCPU to Book3S_32
We need to keep the pointer to the shadow vcpu somewhere accessible from
within really early interrupt code. The best fit I found was the thread
struct, as that resides in an SPRG.

So let's put a pointer to the shadow vcpu in the thread struct and add
an asm-offset so we can find it.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:43 +03:00
Alexander Graf 0474b259d0 KVM: PPC: Remove fetch fail code
When instruction fetch failed, the inline function hook automatically
detects that and starts the internal guest memory load function. So
whenever we access kvmppc_get_last_inst(), we're sure the result is sane.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:41 +03:00
Alexander Graf 33fd27c7d2 KVM: PPC: Release clean pages as clean
When we mapped a page as read-only, we can just release it as clean to
KVM's page claim mechanisms, because we're pretty sure it hasn't been
touched.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:40 +03:00
Alexander Graf 53e5b8bbbd KVM: PPC: Make SLB switching code the new segment framework
We just introduced generic segment switching code that only needs to call
small macros to do the actual switching, but keeps most of the entry / exit
code generic.

So let's move the SLB switching code over to use this new mechanism.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:38 +03:00
Alexander Graf b79fcdf67e KVM: PPC: Make highmem code generic
Since we now have several fields in the shadow VCPU, we also change
the internal calling convention between the different entry/exit code
layers.

Let's reflect that in the IR=1 code and make sure we use "long" defines
for long field access.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:37 +03:00
Alexander Graf 8c3a4e0b67 KVM: PPC: Make real mode handler generic
The real mode handler code was originally writen for 64 bit Book3S only.
But since we not add 32 bit functionality too, we need to make some tweaks
to it.

This patch basically combines using the "long" access defines and using
fields from the shadow VCPU we just moved there.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:35 +03:00