Commit graph

2195 commits

Author SHA1 Message Date
David A. Long
3820b4d278 uprobes: Move function declarations out of arch
Move the function declarations from the arch headers to the common
header, since only the function bodies are architecture-specific.
These changes are from Vincent Rabin's uprobes patch.

[ oleg: update arch/powerpc/include/asm/uprobes.h ]

Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2013-11-06 19:59:37 +01:00
Benjamin Herrenschmidt
0c4888ef1d powerpc: Fix fatal SLB miss when restoring PPR
When restoring the PPR value, we incorrectly access the thread structure
at a time where MSR:RI is clear, which means we cannot recover from nested
faults. However the thread structure isn't covered by the "bolted" SLB
entries and thus accessing can fault.

This fixes it by splitting the code so that the PPR value is loaded into
a GPR before MSR:RI is cleared.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-11-06 14:13:53 +11:00
Benjamin Herrenschmidt
d7a88c7eb4 powerpc/scom: Enable 64-bit addresses
On P8, XSCOM addresses has a special "indirect" form that
requires more than 32-bits, so let's use u64 everywhere in
the code instead of u32.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-11-06 14:13:49 +11:00
Gleb Natapov
95f328d3ad Merge branch 'kvm-ppc-queue' of git://github.com/agraf/linux-2.6 into queue
Conflicts:
	arch/powerpc/include/asm/processor.h
2013-11-04 10:20:57 +02:00
Vladimir Murzin
a40a2b6707 powerpc/bpf: Fix DIVWU instruction opcode
Currently DIVWU stands for *signed* divw opcode:

7d 2a 4b 96 	divwu   r9,r10,r9
7d 2a 4b d6 	divw    r9,r10,r9

Use the *unsigned* divw opcode for DIVWU.

Suggested-by: Vassili Karpov <av1474@comtv.ru>
Reviewed-by: Vassili Karpov <av1474@comtv.ru>
Signed-off-by: Vladimir Murzin <murzin.v@gmail.com>
Acked-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-31 16:19:20 +11:00
Sudeep KarkadaNagesha
a3e31b4588 of: Move definition of of_find_next_cache_node into common code.
Since the definition of_find_next_cache_node is architecture independent,
the existing definition in powerpc can be moved to driver/of/base.c

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-31 16:19:19 +11:00
Philippe Bergheaud
d0cebfa650 powerpc: word-at-a-time optimization for 64-bit Little Endian
This is an optimization for the PowerPC in 64-bit
little-endian. Bit counting is used in find_zero(), instead
of the multiply and shift.

It is modelled after Alan Modra's PowerPC LE strlen patch
http://sourceware.org/ml/libc-alpha/2013-08/msg00097.html.

Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-31 16:19:16 +11:00
Philippe Bergheaud
9c662cad2f powerpc/bpf: BPF JIT compiler for 64-bit Little Endian
This enables the Berkeley Packet Filter JIT compiler
for the PowerPC running in 64bit Little Endian.

Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-31 16:19:15 +11:00
Vasant Hegde
50bd6153d1 powerpc/powernv: Code update interface
Code update interface for powernv platform. This provides
sysfs interface to pass new image, validate, update and
commit images.

This patch includes:
  - Below OPAL APIs for code update
    - opal_validate_flash()
    - opal_manage_flash()
    - opal_update_flash()

  - Create below sysfs files under /sys/firmware/opal
    - image		: Interface to pass new FW image
    - validate_flash	: Validate candidate image
    - manage_flash	: Commit/Reject operations
    - update_flash	: Flash new candidate image

Updating Image:
  "update_flash" is an interface to indicate flash new FW.
It just passes image SG list to FW. Actual flashing is done
during system reboot time.

Note:
  - SG entry format:
    I have kept version number to keep this list similar to what
    PAPR is defined.

Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 16:12:02 +11:00
Vasant Hegde
6f68b5e2c6 powerpc/powernv: Create opal sysfs directory
Create /sys/firmware/opal directory. We wil use this
interface to fetch opal error logs, firmware update, etc.

Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 16:09:34 +11:00
Anton Blanchard
ef1313deaf powerpc: Add VMX optimised xor for RAID5
Add a VMX optimised xor, used primarily for RAID5. On a POWER7 blade
this is a decent win:

   32regs    : 17932.800 MB/sec
   altivec   : 19724.800 MB/sec

The bigger gain is when the same test is run in SMT4 mode, as it
would if there was a lot of work going on:

   8regs     :  8377.600 MB/sec
   altivec   : 15801.600 MB/sec

I tested this against an array created without the patch, and also
verified it worked as expected on a little endian kernel.

[ Fix !CONFIG_ALTIVEC build -- BenH ]

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 16:02:28 +11:00
Anton Blanchard
733187e295 powerpc/pseries: Fix dedicated processor partition detection
commit f13c13a005 (powerpc: Stop using non-architected shared_proc
field in lppaca) fixed a potential issue with shared/dedicated
partition detection. The old method of detection relied on an
unarchitected field (shared_proc), and this patch switched
to using something architected (a non zero yield_count).

Unfortunately the assertion in the Linux header that yield_count
is only non zero on shared processor partitions is not true. It
turns out dedicated processor partitions can increment yield_count
and as such we falsely detect dedicated partitions as shared.

Fix the comment, and switch back to using the old method.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 16:01:43 +11:00
Alistair Popple
ecb35c3943 powerpc: Fix 64K page size support for PPC44x
PPC44x supports page sizes other than 4K however when 64K page sizes
are selected compilation fails. This is due to a change in the
definition of pgtable_t introduced by the following patch:

commit 5c1f6ee9a3
Author: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
powerpc: Reduce PTE table memory wastage

The above patch only implements the new layout for PPC64 so it doesn't
compile for PPC32 with a 64K page size. Ideally we should implement
the same layout for PPC32 however for the meantime this patch reverts
the definition of pgtable_t for PPC32.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 16:00:51 +11:00
Vaishnavi Bhat
b83941798c powerpc: Fix a typo in comments of va to pa conversion
This patch fixes typo in comments virtual to physical
address conversion.

Signed-off-by: Vaishnavi Bhat <vaishnavi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 16:00:38 +11:00
Robert Jennings
b88c4767d9 powerpc: Move local setup.h declarations to arch includes
Move the few declarations from arch/powerpc/kernel/setup.h
into arch/powerpc/include/asm/setup.h.  This resolves a
sparse warning for arch/powerpc/mm/numa.c which defines
do_init_bootmem() but can't include the setup.h header
in the prior path.

Resolves:
arch/powerpc/mm/numa.c:998:13:
        warning: symbol 'do_init_bootmem' was not declared.
                 Should it be static?

Signed-off-by: Robert C Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 16:00:31 +11:00
Scott Wood
a3821b2af1 powerpc: Fix PPC_EMULATED_STATS build break with sync patch
Commit 9863c28a2a ("powerpc: Emulate sync
instruction variants") introduced a build breakage with
CONFIG_PPC_EMULATED_STATS enabled.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Kumar Gala <galak@kernel.org>
Cc: James Yang <James.Yang@freescale.com>
---
2013-10-28 22:08:55 -05:00
Bharat Bhushan
3743c9b8ce powerpc: export debug registers save function for KVM
KVM need this function when switching from vcpu to user-space
thread. My subsequent patch will use this function.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2013-10-18 18:46:18 -05:00
Bharat Bhushan
51ae8d4a2b powerpc: move debug registers in a structure
This way we can use same data type struct with KVM and
also help in using other debug related function.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Acked-by: Michael Neuling <mikey@neuling.org>
[scottwood@freescale.com: removed obvious debug_reg comment]
Signed-off-by: Scott Wood <scottwood@freescale.com>
2013-10-18 18:44:49 -05:00
Aneesh Kumar K.V
a78b55d1c0 kvm: powerpc: book3s: drop is_hv_enabled
drop is_hv_enabled, because that should not be a callback property

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 18:43:34 +02:00
Aneesh Kumar K.V
cbbc58d4fd kvm: powerpc: book3s: Allow the HV and PR selection per virtual machine
This moves the kvmppc_ops callbacks to be a per VM entity. This
enables us to select HV and PR mode when creating a VM. We also
allow both kvm-hv and kvm-pr kernel module to be loaded. To
achieve this we move /dev/kvm ownership to kvm.ko module. Depending on
which KVM mode we select during VM creation we take a reference
count on respective module

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[agraf: fix coding style]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 18:42:36 +02:00
Gleb Natapov
13acfd5715 Powerpc KVM work is based on a commit after rc4.
Merging master into next to satisfy the dependencies.

Conflicts:
	arch/arm/kvm/reset.c
2013-10-17 17:41:49 +03:00
Aneesh Kumar K.V
5587027ce9 kvm: Add struct kvm arg to memslot APIs
We will use that in the later patch to find the kvm ops handler

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 15:49:23 +02:00
Aneesh Kumar K.V
699cc87641 kvm: powerpc: book3s: Add is_hv_enabled to kvmppc_ops
This help us to identify whether we are running with hypervisor mode KVM
enabled. The change is needed so that we can have both HV and PR kvm
enabled in the same kernel.

If both HV and PR KVM are included, interrupts come in to the HV version
of the kvmppc_interrupt code, which then jumps to the PR handler,
renamed to kvmppc_interrupt_pr, if the guest is a PR guest.

Allowing both PR and HV in the same kernel required some changes to
kvm_dev_ioctl_check_extension(), since the values returned now can't
be selected with #ifdefs as much as previously. We look at is_hv_enabled
to return the right value when checking for capabilities.For capabilities that
are only provided by HV KVM, we return the HV value only if
is_hv_enabled is true. For capabilities provided by PR KVM but not HV,
we return the PR value only if is_hv_enabled is false.

NOTE: in later patch we replace is_hv_enabled with a static inline
function comparing kvm_ppc_ops

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 15:29:09 +02:00
Aneesh Kumar K.V
dd96b2c2dc kvm: powerpc: book3s: Cleanup interrupt handling code
With this patch if HV is included, interrupts come in to the HV version
of the kvmppc_interrupt code, which then jumps to the PR handler,
renamed to kvmppc_interrupt_pr, if the guest is a PR guest. This helps
in enabling both HV and PR, which we do in later patch

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 15:26:31 +02:00
Aneesh Kumar K.V
3a167beac0 kvm: powerpc: Add kvmppc_ops callback
This patch add a new callback kvmppc_ops. This will help us in enabling
both HV and PR KVM together in the same kernel. The actual change to
enable them together is done in the later patch in the series.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[agraf: squash in booke changes]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 15:24:26 +02:00
Aneesh Kumar K.V
9975f5e369 kvm: powerpc: book3s: Add a new config variable CONFIG_KVM_BOOK3S_HV_POSSIBLE
This help ups to select the relevant code in the kernel code
when we later move HV and PR bits as seperate modules. The patch
also makes the config options for PR KVM selectable

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 15:18:28 +02:00
Aneesh Kumar K.V
7aa79938f7 kvm: powerpc: book3s: pr: Rename KVM_BOOK3S_PR to KVM_BOOK3S_PR_POSSIBLE
With later patches supporting PR kvm as a kernel module, the changes
that has to be built into the main kernel binary to enable PR KVM module
is now selected via KVM_BOOK3S_PR_POSSIBLE

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 15:17:49 +02:00
Bharat Bhushan
ce11e48b7f KVM: PPC: E500: Add userspace debug stub support
This patch adds the debug stub support on booke/bookehv.
Now QEMU debug stub can use hw breakpoint, watchpoint and
software breakpoint to debug guest.

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

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

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

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

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

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

Currently we do not support debug resource emulation to guest,
On debug exception, always exit to user space irrespective of
user space is expecting the debug exception or not. If this is
unexpected exception (breakpoint/watchpoint event not set by
userspace) then let us leave the action on user space. This
is similar to what it was before, only thing is that now we
have proper exit state available to user space.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:49:40 +02:00
Bharat Bhushan
547465ef8b KVM: PPC: E500: Using "struct debug_reg"
For KVM also use the "struct debug_reg" defined in asm/processor.h

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:49:39 +02:00
Bharat Bhushan
b12c784123 KVM: PPC: E500: exit to user space on "ehpriv 1" instruction
"ehpriv 1" instruction is used for setting software breakpoints
by user space. This patch adds support to exit to user space
with "run->debug" have relevant information.

As this is the first point we are using run->debug, also defined
the run->debug structure.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:49:39 +02:00
Bharat Bhushan
fc82cf113b powerpc: export debug registers save function for KVM
KVM need this function when switching from vcpu to user-space
thread. My subsequent patch will use this function.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:49:39 +02:00
Bharat Bhushan
95791988fe powerpc: move debug registers in a structure
This way we can use same data type struct with KVM and
also help in using other debug related function.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:49:38 +02:00
Bharat Bhushan
c199efa295 powerpc: book3e: _PAGE_LENDIAN must be _PAGE_ENDIAN
For booke3e _PAGE_ENDIAN is not defined. Infact what is defined
is "_PAGE_LENDIAN" which is wrong and that should be _PAGE_ENDIAN.
There are no compilation errors as
arch/powerpc/include/asm/pte-common.h defines _PAGE_ENDIAN to 0
as it is not defined anywhere.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:49:37 +02:00
Paul Mackerras
44a3add863 KVM: PPC: Book3S HV: Better handling of exceptions that happen in real mode
When an interrupt or exception happens in the guest that comes to the
host, the CPU goes to hypervisor real mode (MMU off) to handle the
exception but doesn't change the MMU context.  After saving a few
registers, we then clear the "in guest" flag.  If, for any reason,
we get an exception in the real-mode code, that then gets handled
by the normal kernel exception handlers, which turn the MMU on.  This
is disastrous if the MMU is still set to the guest context, since we
end up executing instructions from random places in the guest kernel
with hypervisor privilege.

In order to catch this situation, we define a new value for the "in guest"
flag, KVM_GUEST_MODE_HOST_HV, to indicate that we are in hypervisor real
mode with guest MMU context.  If the "in guest" flag is set to this value,
we branch off to an emergency handler.  For the moment, this just does
a branch to self to stop the CPU from doing anything further.

While we're here, we define another new flag value to indicate that we
are in a HV guest, as distinct from a PR guest.  This will be useful
when we have a kernel that can support both PR and HV guests concurrently.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:49:37 +02:00
Paul Mackerras
d78bca7296 KVM: PPC: Book3S PR: Use mmu_notifier_retry() in kvmppc_mmu_map_page()
When the MM code is invalidating a range of pages, it calls the KVM
kvm_mmu_notifier_invalidate_range_start() notifier function, which calls
kvm_unmap_hva_range(), which arranges to flush all the existing host
HPTEs for guest pages.  However, the Linux PTEs for the range being
flushed are still valid at that point.  We are not supposed to establish
any new references to pages in the range until the ...range_end()
notifier gets called.  The PPC-specific KVM code doesn't get any
explicit notification of that; instead, we are supposed to use
mmu_notifier_retry() to test whether we are or have been inside a
range flush notifier pair while we have been getting a page and
instantiating a host HPTE for the page.

This therefore adds a call to mmu_notifier_retry inside
kvmppc_mmu_map_page().  This call is inside a region locked with
kvm->mmu_lock, which is the same lock that is called by the KVM
MMU notifier functions, thus ensuring that no new notification can
proceed while we are in the locked region.  Inside this region we
also create the host HPTE and link the corresponding hpte_cache
structure into the lists used to find it later.  We cannot allocate
the hpte_cache structure inside this locked region because that can
lead to deadlock, so we allocate it outside the region and free it
if we end up not using it.

This also moves the updates of vcpu3s->hpte_cache_count inside the
regions locked with vcpu3s->mmu_lock, and does the increment in
kvmppc_mmu_hpte_cache_map() when the pte is added to the cache
rather than when it is allocated, in order that the hpte_cache_count
is accurate.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:49:35 +02:00
Paul Mackerras
93b159b466 KVM: PPC: Book3S PR: Better handling of host-side read-only pages
Currently we request write access to all pages that get mapped into the
guest, even if the guest is only loading from the page.  This reduces
the effectiveness of KSM because it means that we unshare every page we
access.  Also, we always set the changed (C) bit in the guest HPTE if
it allows writing, even for a guest load.

This fixes both these problems.  We pass an 'iswrite' flag to the
mmu.xlate() functions and to kvmppc_mmu_map_page() to indicate whether
the access is a load or a store.  The mmu.xlate() functions now only
set C for stores.  kvmppc_gfn_to_pfn() now calls gfn_to_pfn_prot()
instead of gfn_to_pfn() so that it can indicate whether we need write
access to the page, and get back a 'writable' flag to indicate whether
the page is writable or not.  If that 'writable' flag is clear, we then
make the host HPTE read-only even if the guest HPTE allowed writing.

This means that we can get a protection fault when the guest writes to a
page that it has mapped read-write but which is read-only on the host
side (perhaps due to KSM having merged the page).  Thus we now call
kvmppc_handle_pagefault() for protection faults as well as HPTE not found
faults.  In kvmppc_handle_pagefault(), if the access was allowed by the
guest HPTE and we thus need to install a new host HPTE, we then need to
remove the old host HPTE if there is one.  This is done with a new
function, kvmppc_mmu_unmap_page(), which uses kvmppc_mmu_pte_vflush() to
find and remove the old host HPTE.

Since the memslot-related functions require the KVM SRCU read lock to
be held, this adds srcu_read_lock/unlock pairs around the calls to
kvmppc_handle_pagefault().

Finally, this changes kvmppc_mmu_book3s_32_xlate_pte() to not ignore
guest HPTEs that don't permit access, and to return -EPERM for accesses
that are not permitted by the page protections.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:49:35 +02:00
Paul Mackerras
3ff955024d KVM: PPC: Book3S PR: Allocate kvm_vcpu structs from kvm_vcpu_cache
This makes PR KVM allocate its kvm_vcpu structs from the kvm_vcpu_cache
rather than having them embedded in the kvmppc_vcpu_book3s struct,
which is allocated with vzalloc.  The reason is to reduce the
differences between PR and HV KVM in order to make is easier to have
them coexist in one kernel binary.

With this, the kvm_vcpu struct has a pointer to the kvmppc_vcpu_book3s
struct.  The pointer to the kvmppc_book3s_shadow_vcpu struct has moved
from the kvmppc_vcpu_book3s struct to the kvm_vcpu struct, and is only
present for 32-bit, since it is only used for 32-bit.

Signed-off-by: Paul Mackerras <paulus@samba.org>
[agraf: squash in compile fix from Aneesh]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:45:05 +02:00
Paul Mackerras
9308ab8e2d KVM: PPC: Book3S PR: Make HPT accesses and updates SMP-safe
This adds a per-VM mutex to provide mutual exclusion between vcpus
for accesses to and updates of the guest hashed page table (HPT).
This also makes the code use single-byte writes to the HPT entry
when updating of the reference (R) and change (C) bits.  The reason
for doing this, rather than writing back the whole HPTE, is that on
non-PAPR virtual machines, the guest OS might be writing to the HPTE
concurrently, and writing back the whole HPTE might conflict with
that.  Also, real hardware does single-byte writes to update R and C.

The new mutex is taken in kvmppc_mmu_book3s_64_xlate() when reading
the HPT and updating R and/or C, and in the PAPR HPT update hcalls
(H_ENTER, H_REMOVE, etc.).  Having the mutex means that we don't need
to use a hypervisor lock bit in the HPT update hcalls, and we don't
need to be careful about the order in which the bytes of the HPTE are
updated by those hcalls.

The other change here is to make emulated TLB invalidations (tlbie)
effective across all vcpus.  To do this we call kvmppc_mmu_pte_vflush
for all vcpus in kvmppc_ppc_book3s_64_tlbie().

For 32-bit, this makes the setting of the accessed and dirty bits use
single-byte writes, and makes tlbie invalidate shadow HPTEs for all
vcpus.

With this, PR KVM can successfully run SMP guests.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:45:04 +02:00
Paul Mackerras
c9029c341d KVM: PPC: Book3S PR: Use 64k host pages where possible
Currently, PR KVM uses 4k pages for the host-side mappings of guest
memory, regardless of the host page size.  When the host page size is
64kB, we might as well use 64k host page mappings for guest mappings
of 64kB and larger pages and for guest real-mode mappings.  However,
the magic page has to remain a 4k page.

To implement this, we first add another flag bit to the guest VSID
values we use, to indicate that this segment is one where host pages
should be mapped using 64k pages.  For segments with this bit set
we set the bits in the shadow SLB entry to indicate a 64k base page
size.  When faulting in host HPTEs for this segment, we make them
64k HPTEs instead of 4k.  We record the pagesize in struct hpte_cache
for use when invalidating the HPTE.

For now we restrict the segment containing the magic page (if any) to
4k pages.  It should be possible to lift this restriction in future
by ensuring that the magic 4k page is appropriately positioned within
a host 64k page.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:45:03 +02:00
Paul Mackerras
a4a0f2524a KVM: PPC: Book3S PR: Allow guest to use 64k pages
This adds the code to interpret 64k HPTEs in the guest hashed page
table (HPT), 64k SLB entries, and to tell the guest about 64k pages
in kvm_vm_ioctl_get_smmu_info().  Guest 64k pages are still shadowed
by 4k pages.

This also adds another hash table to the four we have already in
book3s_mmu_hpte.c to allow us to find all the PTEs that we have
instantiated that match a given 64k guest page.

The tlbie instruction changed starting with POWER6 to use a bit in
the RB operand to indicate large page invalidations, and to use other
RB bits to indicate the base and actual page sizes and the segment
size.  64k pages came in slightly earlier, with POWER5++.
We use one bit in vcpu->arch.hflags to indicate that the emulated
cpu supports 64k pages, and another to indicate that it has the new
tlbie definition.

The KVM_PPC_GET_SMMU_INFO ioctl presents a bit of a problem, because
the MMU capabilities depend on which CPU model we're emulating, but it
is a VM ioctl not a VCPU ioctl and therefore doesn't get passed a VCPU
fd.  In addition, commonly-used userspace (QEMU) calls it before
setting the PVR for any VCPU.  Therefore, as a best effort we look at
the first vcpu in the VM and return 64k pages or not depending on its
capabilities.  We also make the PVR default to the host PVR on recent
CPUs that support 1TB segments (and therefore multiple page sizes as
well) so that KVM_PPC_GET_SMMU_INFO will include 64k page and 1TB
segment support on those CPUs.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:45:03 +02:00
Paul Mackerras
a2d56020d1 KVM: PPC: Book3S PR: Keep volatile reg values in vcpu rather than shadow_vcpu
Currently PR-style KVM keeps the volatile guest register values
(R0 - R13, CR, LR, CTR, XER, PC) in a shadow_vcpu struct rather than
the main kvm_vcpu struct.  For 64-bit, the shadow_vcpu exists in two
places, a kmalloc'd struct and in the PACA, and it gets copied back
and forth in kvmppc_core_vcpu_load/put(), because the real-mode code
can't rely on being able to access the kmalloc'd struct.

This changes the code to copy the volatile values into the shadow_vcpu
as one of the last things done before entering the guest.  Similarly
the values are copied back out of the shadow_vcpu to the kvm_vcpu
immediately after exiting the guest.  We arrange for interrupts to be
still disabled at this point so that we can't get preempted on 64-bit
and end up copying values from the wrong PACA.

This means that the accessor functions in kvm_book3s.h for these
registers are greatly simplified, and are same between PR and HV KVM.
In places where accesses to shadow_vcpu fields are now replaced by
accesses to the kvm_vcpu, we can also remove the svcpu_get/put pairs.
Finally, on 64-bit, we don't need the kmalloc'd struct at all any more.

With this, the time to read the PVR one million times in a loop went
from 567.7ms to 575.5ms (averages of 6 values), an increase of about
1.4% for this worse-case test for guest entries and exits.  The
standard deviation of the measurements is about 11ms, so the
difference is only marginally significant statistically.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:45:03 +02:00
Paul Mackerras
388cc6e133 KVM: PPC: Book3S HV: Support POWER6 compatibility mode on POWER7
This enables us to use the Processor Compatibility Register (PCR) on
POWER7 to put the processor into architecture 2.05 compatibility mode
when running a guest.  In this mode the new instructions and registers
that were introduced on POWER7 are disabled in user mode.  This
includes all the VSX facilities plus several other instructions such
as ldbrx, stdbrx, popcntw, popcntd, etc.

To select this mode, we have a new register accessible through the
set/get_one_reg interface, called KVM_REG_PPC_ARCH_COMPAT.  Setting
this to zero gives the full set of capabilities of the processor.
Setting it to one of the "logical" PVR values defined in PAPR puts
the vcpu into the compatibility mode for the corresponding
architecture level.  The supported values are:

0x0f000002	Architecture 2.05 (POWER6)
0x0f000003	Architecture 2.06 (POWER7)
0x0f100003	Architecture 2.06+ (POWER7+)

Since the PCR is per-core, the architecture compatibility level and
the corresponding PCR value are stored in the struct kvmppc_vcore, and
are therefore shared between all vcpus in a virtual core.

Signed-off-by: Paul Mackerras <paulus@samba.org>
[agraf: squash in fix to add missing break statements and documentation]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:45:02 +02:00
Paul Mackerras
4b8473c9c1 KVM: PPC: Book3S HV: Add support for guest Program Priority Register
POWER7 and later IBM server processors have a register called the
Program Priority Register (PPR), which controls the priority of
each hardware CPU SMT thread, and affects how fast it runs compared
to other SMT threads.  This priority can be controlled by writing to
the PPR or by use of a set of instructions of the form or rN,rN,rN
which are otherwise no-ops but have been defined to set the priority
to particular levels.

This adds code to context switch the PPR when entering and exiting
guests and to make the PPR value accessible through the SET/GET_ONE_REG
interface.  When entering the guest, we set the PPR as late as
possible, because if we are setting a low thread priority it will
make the code run slowly from that point on.  Similarly, the
first-level interrupt handlers save the PPR value in the PACA very
early on, and set the thread priority to the medium level, so that
the interrupt handling code runs at a reasonable speed.

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:45:02 +02:00
Paul Mackerras
a0144e2a6b KVM: PPC: Book3S HV: Store LPCR value for each virtual core
This adds the ability to have a separate LPCR (Logical Partitioning
Control Register) value relating to a guest for each virtual core,
rather than only having a single value for the whole VM.  This
corresponds to what real POWER hardware does, where there is a LPCR
per CPU thread but most of the fields are required to have the same
value on all active threads in a core.

The per-virtual-core LPCR can be read and written using the
GET/SET_ONE_REG interface.  Userspace can can only modify the
following fields of the LPCR value:

DPFD	Default prefetch depth
ILE	Interrupt little-endian
TC	Translation control (secondary HPT hash group search disable)

We still maintain a per-VM default LPCR value in kvm->arch.lpcr, which
contains bits relating to memory management, i.e. the Virtualized
Partition Memory (VPM) bits and the bits relating to guest real mode.
When this default value is updated, the update needs to be propagated
to the per-vcore values, so we add a kvmppc_update_lpcr() helper to do
that.

Signed-off-by: Paul Mackerras <paulus@samba.org>
[agraf: fix whitespace]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:45:01 +02:00
Paul Mackerras
93b0f4dc29 KVM: PPC: Book3S HV: Implement timebase offset for guests
This allows guests to have a different timebase origin from the host.
This is needed for migration, where a guest can migrate from one host
to another and the two hosts might have a different timebase origin.
However, the timebase seen by the guest must not go backwards, and
should go forwards only by a small amount corresponding to the time
taken for the migration.

Therefore this provides a new per-vcpu value accessed via the one_reg
interface using the new KVM_REG_PPC_TB_OFFSET identifier.  This value
defaults to 0 and is not modified by KVM.  On entering the guest, this
value is added onto the timebase, and on exiting the guest, it is
subtracted from the timebase.

This is only supported for recent POWER hardware which has the TBU40
(timebase upper 40 bits) register.  Writing to the TBU40 register only
alters the upper 40 bits of the timebase, leaving the lower 24 bits
unchanged.  This provides a way to modify the timebase for guest
migration without disturbing the synchronization of the timebase
registers across CPU cores.  The kernel rounds up the value given
to a multiple of 2^24.

Timebase values stored in KVM structures (struct kvm_vcpu, struct
kvmppc_vcore, etc.) are stored as host timebase values.  The timebase
values in the dispatch trace log need to be guest timebase values,
however, since that is read directly by the guest.  This moves the
setting of vcpu->arch.dec_expires on guest exit to a point after we
have restored the host timebase so that vcpu->arch.dec_expires is a
host timebase value.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:44:59 +02:00
Paul Mackerras
14941789f2 KVM: PPC: Book3S HV: Save/restore SIAR and SDAR along with other PMU registers
Currently we are not saving and restoring the SIAR and SDAR registers in
the PMU (performance monitor unit) on guest entry and exit.  The result
is that performance monitoring tools in the guest could get false
information about where a program was executing and what data it was
accessing at the time of a performance monitor interrupt.  This fixes
it by saving and restoring these registers along with the other PMU
registers on guest entry/exit.

This also provides a way for userspace to access these values for a
vcpu via the one_reg interface.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 14:44:59 +02:00
James Yang
9863c28a2a powerpc: Emulate sync instruction variants
Reserved fields of the sync instruction have been used for other
instructions (e.g. lwsync).  On processors that do not support variants
of the sync instruction, emulate it by executing a sync to subsume the
effect of the intended instruction.

Signed-off-by: James Yang <James.Yang@freescale.com>
[scottwood@freescale.com: whitespace and subject line fix]
Signed-off-by: Scott Wood <scottwood@freescale.com>
2013-10-16 18:51:18 -05:00
Christoffer Dall
2c5350e934 KVM: PPC: Get rid of KVM_HPAGE defines
Now when the main kvm code relying on these defines has been moved to
the x86 specific part of the world, we can get rid of these.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-14 10:12:11 +03:00
Benjamin Herrenschmidt
3ad26e5c44 Merge branch 'for-kvm' into next
Topic branch for commits that the KVM tree might want to pull
in separately.

Hand merged a few files due to conflicts with the LE stuff

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-11 18:23:53 +11:00
Paul Mackerras
18461960cb powerpc: Provide for giveup_fpu/altivec to save state in alternate location
This provides a facility which is intended for use by KVM, where the
contents of the FP/VSX and VMX (Altivec) registers can be saved away
to somewhere other than the thread_struct when kernel code wants to
use floating point or VMX instructions.  This is done by providing a
pointer in the thread_struct to indicate where the state should be
saved to.  The giveup_fpu() and giveup_altivec() functions test these
pointers and save state to the indicated location if they are non-NULL.
Note that the MSR_FP/VEC bits in task->thread.regs->msr are still used
to indicate whether the CPU register state is live, even when an
alternate save location is being used.

This also provides load_fp_state() and load_vr_state() functions, which
load up FP/VSX and VMX state from memory into the CPU registers, and
corresponding store_fp_state() and store_vr_state() functions, which
store FP/VSX and VMX state into memory from the CPU registers.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-11 17:26:50 +11:00