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>
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>
Add kvm_release_page_clean() after is_error_page() to avoid
leakage of error page.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Instead of instantiating a whole thread_struct on the stack use only the
required parts of it.
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Tested-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
All vcpu ioctls need to be locked, so instead of locking each one specifically
we lock at the generic dispatcher.
This patch only updates generic ioctls and leaves arch specific ioctls alone.
Signed-off-by: Avi Kivity <avi@redhat.com>
vmx and svm vcpus have different contents and therefore may have different
alignmment requirements. Let each specify its required alignment.
Signed-off-by: Avi Kivity <avi@redhat.com>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Cell can't handle MSR_FE0 and MSR_FE1 too well. It gets dog slow.
So let's just override the guest whenever we see one of the two and mask them
out. See commit ddf5f75a16 for reference.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
On most systems we need to emulate dcbz when running 32 bit guests. So
far we've been rather slack, not giving correct DSISR values to the guest.
This patch makes the emulation more accurate, introducing a difference
between "page not mapped" and "write protection fault". While at it, it
also speeds up dcbz emulation by an order of magnitude by using kmap.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
The FPU/Altivec/VSX enablement also brought access to some structure
elements that are only defined when the respective config options
are enabled.
Unfortuately I forgot to check for the config options at some places,
so let's do that now.
Unbreaks the build when CONFIG_VSX is not set.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
MOL uses its own hypercall interface to call back into userspace when
the guest wants to do something.
So let's implement that as an exit reason, specify it with a CAP and
only really use it when userspace wants us to.
The only user of it so far is MOL.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Mac OS X has some applications - namely the Finder - that require alignment
interrupts to work properly. So we need to implement them.
But the spec for 970 and 750 also looks different. While 750 requires the
DSISR and DAR fields to reflect some instruction bits (DSISR) and the fault
address (DAR), the 970 declares this as an optional feature. So we need
to reconstruct DSISR and DAR manually.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
When trying to read or store vcpu register data, we should also make
sure the vcpu is actually loaded, so we're 100% sure we get the correct
values.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
When the guest activates the FPU, we load it up. That's fine when
it wasn't activated before on the host, but if it was we end up
reloading FPU values from last time the FPU was deactivated on the
host without writing the proper values back to the vcpu struct.
This patch checks if the FPU is enabled already and if so just doesn't
bother activating it, making FPU operations survive guest context switches.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
The current check_ext function reads the instruction and then does
the checking. Let's split the reading out so we can reuse it for
different functions.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Userspace can tell us that it wants to trigger an interrupt. But
so far it can't tell us that it wants to stop triggering one.
So let's interpret the parameter to the ioctl that we have anyways
to tell us if we want to raise or lower the interrupt line.
Signed-off-by: Alexander Graf <agraf@suse.de>
v2 -> v3:
- Add CAP for unset irq
Signed-off-by: Avi Kivity <avi@redhat.com>
On PowerPC we can go into MMU Split Mode. That means that either
data relocation is on but instruction relocation is off or vice
versa.
That mode didn't work properly, as we weren't always flushing
entries when going into a new split mode, potentially mapping
different code or data that we're supposed to.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
While converting the kzalloc we used to allocate our vcpu struct to
vmalloc, I forgot to memset the contents to zeros. That broke quite
a lot.
This patch memsets it to zero again.
Signed-off-by: Alexander Graf <alex@csgraf.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
We used to use get_free_pages to allocate our vcpu struct. Unfortunately
that call failed on me several times after my machine had a big enough
uptime, as memory became too fragmented by then.
Fortunately, we don't need it to be page aligned any more! We can just
vmalloc it and everything's great.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
When we get a program interrupt we usually don't expect it to perform an
MMIO operation. But why not? When we emulate paired singles, we can end
up loading or storing to an MMIO address - and the handling of those
happens in the program interrupt handler.
So let's teach the program interrupt handler how to deal with EMULATE_MMIO.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
We need to call the ext giveup handlers from code outside of book3s.c.
So let's make it non-static.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
The Book3S KVM implementation contains some helper functions to load and store
data from and to virtual addresses.
Unfortunately, this helper used to keep the physical address it so nicely
found out for us to itself. So let's change that and make it return the
physical address it resolved.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
There are some situations when we're pretty sure the guest will use the
FPU soon. So we can save the churn of going into the guest, finding out
it does want to use the FPU and going out again.
This patch adds preloading of the FPU when it's reasonable.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
When we for example get an Altivec interrupt, but our guest doesn't support
altivec, we need to inject a program interrupt, not an altivec interrupt.
The same goes for paired singles. When an altivec interrupt arrives, we're
pretty sure we need to emulate the instruction because it's a paired single
operation.
So let's make all the ext handlers aware that they need to jump to the
program interrupt handler when an extension interrupt arrives that
was not supposed to arrive for the guest CPU.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
The Gekko implements an extension called paired singles. When the guest wants
to use that extension, we need to make sure we're not running the host FPU,
because all FPU instructions need to get emulated to accomodate for additional
operations that occur.
This patch adds an hflag to track if we're in paired single mode or not.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Emulation of an instruction can have different outcomes. It can succeed,
fail, require MMIO, do funky BookE stuff - or it can just realize something's
odd and will be fixed the next time around.
Exactly that is what EMULATE_AGAIN means. Using that flag we can now tell
the caller that nothing happened, but we still want to go back to the
guest and see what happens next time we come around.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Int is not long enough to store the size of a dirty bitmap.
This patch fixes this problem with the introduction of a wrapper
function to calculate the sizes of dirty bitmaps.
Note: in mark_page_dirty(), we have to consider the fact that
__set_bit() takes the offset as int, not long.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
