Commit Graph

21 Commits

Author SHA1 Message Date
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 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 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 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
Gleb Natapov 49451389ec KVM: PPC: correctly check gfn_to_pfn() return value
On failure gfn_to_pfn returns bad_page so use correct function to check
for that.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
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 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 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 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 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 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 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 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 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 9cc5e9538a KVM: PPC: Extract MMU init
The host shadow mmu code needs to get initialized. It needs to fetch a
segment it can use to put shadow PTEs into.

That initialization code was in generic code, which is icky. Let's move
it over to the respective MMU file.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:34 +03:00
Alexander Graf c7f38f46f2 KVM: PPC: Improve indirect svcpu accessors
We already have some inline fuctions we use to access vcpu or svcpu structs,
depending on whether we're on booke or book3s. Since we just put a few more
registers into the svcpu, we also need to make sure the respective callbacks
are available and get used.

So this patch moves direct use of the now in the svcpu struct fields to
inline function calls. While at it, it also moves the definition of those
inline function calls to respective header files for booke and book3s,
greatly improving readability.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:26 +03:00
Alexander Graf a1eda280cc KVM: PPC: Add check if pte was mapped secondary
Some HTAB providers (namely the PS3) ignore the SECONDARY flag. They
just put an entry in the htab as secondary when they see fit.

So we need to check the return value of htab_insert to remember the
correct slot id so we can actually invalidate the entry again.

Fixes KVM on the PS3.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:17:17 +03:00
Alexander Graf 20a340abd3 KVM: PPC: Enable use of secondary htab bucket
We had code to make use of the secondary htab buckets, but kept that
disabled because it was unstable when I put it in.

I checked again if that's still the case and apparently it was only
exposing some instability that was there anyways before. I haven't
seen any badness related to usage of secondary htab entries so far.

This should speed up guest memory allocations by quite a bit, because
we now have more space to put PTEs in.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:37:58 +03:00
Alexander Graf 0d8dc681c8 Add book3s_64 Host MMU handling
We designed the Book3S port of KVM as modular as possible. Most
of the code could be easily used on a Book3S_32 host as well.

The main difference between 32 and 64 bit cores is the MMU. To keep
things well separated, we treat the book3s_64 MMU as one possible compile
option.

This patch adds all the MMU helpers the rest of the code needs in
order to modify the host's MMU, like setting PTEs and segments.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-11-05 16:49:54 +11:00