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172 Commits (0d1e8b8d2bcd3150d51754d8d0fdbf44dc88b0d3)

Author SHA1 Message Date
Paul Mackerras aa069a9969 KVM: PPC: Book3S HV: Add a VM capability to enable nested virtualization
With this, userspace can enable a KVM-HV guest to run nested guests
under it.

The administrator can control whether any nested guests can be run;
setting the "nested" module parameter to false prevents any guests
becoming nested hypervisors (that is, any attempt to enable the nested
capability on a guest will fail).  Guests which are already nested
hypervisors will continue to be so.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-10-09 16:14:47 +11:00
Paul Mackerras 95a6432ce9 KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests
This creates an alternative guest entry/exit path which is used for
radix guests on POWER9 systems when we have indep_threads_mode=Y.  In
these circumstances there is exactly one vcpu per vcore and there is
no coordination required between vcpus or vcores; the vcpu can enter
the guest without needing to synchronize with anything else.

The new fast path is implemented almost entirely in C in book3s_hv.c
and runs with the MMU on until the guest is entered.  On guest exit
we use the existing path until the point where we are committed to
exiting the guest (as distinct from handling an interrupt in the
low-level code and returning to the guest) and we have pulled the
guest context from the XIVE.  At that point we check a flag in the
stack frame to see whether we came in via the old path and the new
path; if we came in via the new path then we go back to C code to do
the rest of the process of saving the guest context and restoring the
host context.

The C code is split into separate functions for handling the
OS-accessible state and the hypervisor state, with the idea that the
latter can be replaced by a hypercall when we implement nested
virtualization.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[mpe: Fix CONFIG_ALTIVEC=n build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 16:04:27 +11:00
Paul Mackerras f7035ce9f1 KVM: PPC: Book3S HV: Move interrupt delivery on guest entry to C code
This is based on a patch by Suraj Jitindar Singh.

This moves the code in book3s_hv_rmhandlers.S that generates an
external, decrementer or privileged doorbell interrupt just before
entering the guest to C code in book3s_hv_builtin.c.  This is to
make future maintenance and modification easier.  The algorithm
expressed in the C code is almost identical to the previous
algorithm.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 16:04:27 +11:00
Alexey Kardashevskiy a3ac077b75 KVM: PPC: Remove redundand permission bits removal
The kvmppc_gpa_to_ua() helper itself takes care of the permission
bits in the TCE and yet every single caller removes them.

This changes semantics of kvmppc_gpa_to_ua() so it takes TCEs
(which are GPAs + TCE permission bits) to make the callers simpler.

This should cause no behavioural change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 16:04:27 +11:00
Alexey Kardashevskiy 42de7b9e21 KVM: PPC: Validate TCEs against preregistered memory page sizes
The userspace can request an arbitrary supported page size for a DMA
window and this works fine as long as the mapped memory is backed with
the pages of the same or bigger size; if this is not the case,
mm_iommu_ua_to_hpa{_rm}() fail and tables do not populated with
dangerously incorrect TCEs.

However since it is quite easy to misconfigure the KVM and we do not do
reverts to all changes made to TCE tables if an error happens in a middle,
we better do the acceptable page size validation before we even touch
the tables.

This enhances kvmppc_tce_validate() to check the hardware IOMMU page sizes
against the preregistered memory page sizes.

Since the new check uses real/virtual mode helpers, this renames
kvmppc_tce_validate() to kvmppc_rm_tce_validate() to handle the real mode
case and mirrors it for the virtual mode under the old name. The real
mode handler is not used for the virtual mode as:
1. it uses _lockless() list traversing primitives instead of RCU;
2. realmode's mm_iommu_ua_to_hpa_rm() uses vmalloc_to_phys() which
virtual mode does not have to use and since on POWER9+radix only virtual
mode handlers actually work, we do not want to slow down that path even
a bit.

This removes EXPORT_SYMBOL_GPL(kvmppc_tce_validate) as the validators
are static now.

From now on the attempts on mapping IOMMU pages bigger than allowed
will result in KVM exit.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[mpe: Fix KVM_HV=n build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 15:45:15 +11:00
Simon Guo acc9eb9305 KVM: PPC: Reimplement LOAD_VMX/STORE_VMX instruction mmio emulation with analyse_instr() input
This patch reimplements LOAD_VMX/STORE_VMX MMIO emulation with
analyse_instr() input. When emulating the store, the VMX reg will need to
be flushed so that the right reg val can be retrieved before writing to
IO MEM.

This patch also adds support for lvebx/lvehx/lvewx/stvebx/stvehx/stvewx
MMIO emulation. To meet the requirement of handling different element
sizes, kvmppc_handle_load128_by2x64()/kvmppc_handle_store128_by2x64()
were replaced with kvmppc_handle_vmx_load()/kvmppc_handle_vmx_store().

The framework used is similar to VSX instruction MMIO emulation.

Suggested-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-22 19:53:00 +10:00
Simon Guo 2e6baa46b4 KVM: PPC: Add giveup_ext() hook to PPC KVM ops
Currently HV will save math regs(FP/VEC/VSX) when trap into host. But
PR KVM will only save math regs when qemu task switch out of CPU, or
when returning from qemu code.

To emulate FP/VEC/VSX mmio load, PR KVM need to make sure that math
regs were flushed firstly and then be able to update saved VCPU
FPR/VEC/VSX area reasonably.

This patch adds giveup_ext() field to KVM ops. Only PR KVM has non-NULL
giveup_ext() ops. kvmppc_complete_mmio_load() can invoke that hook
(when not NULL) to flush math regs accordingly, before updating saved
register vals.

Math regs flush is also necessary for STORE, which will be covered
in later patch within this patch series.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-22 19:51:13 +10:00
Simon Guo 7092360399 KVM: PPC: Reimplement non-SIMD LOAD/STORE instruction mmio emulation with analyse_instr() input
This patch reimplements non-SIMD LOAD/STORE instruction MMIO emulation
with analyse_instr() input. It utilizes the BYTEREV/UPDATE/SIGNEXT
properties exported by analyse_instr() and invokes
kvmppc_handle_load(s)/kvmppc_handle_store() accordingly.

It also moves CACHEOP type handling into the skeleton.

instruction_type within kvm_ppc.h is renamed to avoid conflict with
sstep.h.

Suggested-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-22 19:51:08 +10:00
Linus Torvalds d8312a3f61 ARM:
- VHE optimizations
 - EL2 address space randomization
 - speculative execution mitigations ("variant 3a", aka execution past invalid
 privilege register access)
 - bugfixes and cleanups
 
 PPC:
 - improvements for the radix page fault handler for HV KVM on POWER9
 
 s390:
 - more kvm stat counters
 - virtio gpu plumbing
 - documentation
 - facilities improvements
 
 x86:
 - support for VMware magic I/O port and pseudo-PMCs
 - AMD pause loop exiting
 - support for AMD core performance extensions
 - support for synchronous register access
 - expose nVMX capabilities to userspace
 - support for Hyper-V signaling via eventfd
 - use Enlightened VMCS when running on Hyper-V
 - allow userspace to disable MWAIT/HLT/PAUSE vmexits
 - usual roundup of optimizations and nested virtualization bugfixes
 
 Generic:
 - API selftest infrastructure (though the only tests are for x86 as of now)
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:
   - VHE optimizations

   - EL2 address space randomization

   - speculative execution mitigations ("variant 3a", aka execution past
     invalid privilege register access)

   - bugfixes and cleanups

  PPC:
   - improvements for the radix page fault handler for HV KVM on POWER9

  s390:
   - more kvm stat counters

   - virtio gpu plumbing

   - documentation

   - facilities improvements

  x86:
   - support for VMware magic I/O port and pseudo-PMCs

   - AMD pause loop exiting

   - support for AMD core performance extensions

   - support for synchronous register access

   - expose nVMX capabilities to userspace

   - support for Hyper-V signaling via eventfd

   - use Enlightened VMCS when running on Hyper-V

   - allow userspace to disable MWAIT/HLT/PAUSE vmexits

   - usual roundup of optimizations and nested virtualization bugfixes

  Generic:
   - API selftest infrastructure (though the only tests are for x86 as
     of now)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (174 commits)
  kvm: x86: fix a prototype warning
  kvm: selftests: add sync_regs_test
  kvm: selftests: add API testing infrastructure
  kvm: x86: fix a compile warning
  KVM: X86: Add Force Emulation Prefix for "emulate the next instruction"
  KVM: X86: Introduce handle_ud()
  KVM: vmx: unify adjacent #ifdefs
  x86: kvm: hide the unused 'cpu' variable
  KVM: VMX: remove bogus WARN_ON in handle_ept_misconfig
  Revert "KVM: X86: Fix SMRAM accessing even if VM is shutdown"
  kvm: Add emulation for movups/movupd
  KVM: VMX: raise internal error for exception during invalid protected mode state
  KVM: nVMX: Optimization: Dont set KVM_REQ_EVENT when VMExit with nested_run_pending
  KVM: nVMX: Require immediate-exit when event reinjected to L2 and L1 event pending
  KVM: x86: Fix misleading comments on handling pending exceptions
  KVM: x86: Rename interrupt.pending to interrupt.injected
  KVM: VMX: No need to clear pending NMI/interrupt on inject realmode interrupt
  x86/kvm: use Enlightened VMCS when running on Hyper-V
  x86/hyper-v: detect nested features
  x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits
  ...
2018-04-09 11:42:31 -07:00
Nicholas Piggin d2e60075a3 powerpc/64: Use array of paca pointers and allocate pacas individually
Change the paca array into an array of pointers to pacas. Allocate
pacas individually.

This allows flexibility in where the PACAs are allocated. Future work
will allocate them node-local. Platforms that don't have address limits
on PACAs would be able to defer PACA allocations until later in boot
rather than allocate all possible ones up-front then freeing unused.

This is slightly more overhead (one additional indirection) for cross
CPU paca references, but those aren't too common.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:23 +11:00
Paul Mackerras 39c983ea0f KVM: PPC: Remove unused kvm_unmap_hva callback
Since commit fb1522e099 ("KVM: update to new mmu_notifier semantic
v2", 2017-08-31), the MMU notifier code in KVM no longer calls the
kvm_unmap_hva callback.  This removes the PPC implementations of
kvm_unmap_hva().

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-03-19 10:08:29 +11:00
Linus Torvalds 15303ba5d1 KVM changes for 4.16
ARM:
 - Include icache invalidation optimizations, improving VM startup time
 
 - Support for forwarded level-triggered interrupts, improving
   performance for timers and passthrough platform devices
 
 - A small fix for power-management notifiers, and some cosmetic changes
 
 PPC:
 - Add MMIO emulation for vector loads and stores
 
 - Allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without
   requiring the complex thread synchronization of older CPU versions
 
 - Improve the handling of escalation interrupts with the XIVE interrupt
   controller
 
 - Support decrement register migration
 
 - Various cleanups and bugfixes.
 
 s390:
 - Cornelia Huck passed maintainership to Janosch Frank
 
 - Exitless interrupts for emulated devices
 
 - Cleanup of cpuflag handling
 
 - kvm_stat counter improvements
 
 - VSIE improvements
 
 - mm cleanup
 
 x86:
 - Hypervisor part of SEV
 
 - UMIP, RDPID, and MSR_SMI_COUNT emulation
 
 - Paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit
 
 - Allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more AVX512
   features
 
 - Show vcpu id in its anonymous inode name
 
 - Many fixes and cleanups
 
 - Per-VCPU MSR bitmaps (already merged through x86/pti branch)
 
 - Stable KVM clock when nesting on Hyper-V (merged through x86/hyperv)
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Merge tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "ARM:

   - icache invalidation optimizations, improving VM startup time

   - support for forwarded level-triggered interrupts, improving
     performance for timers and passthrough platform devices

   - a small fix for power-management notifiers, and some cosmetic
     changes

  PPC:

   - add MMIO emulation for vector loads and stores

   - allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without
     requiring the complex thread synchronization of older CPU versions

   - improve the handling of escalation interrupts with the XIVE
     interrupt controller

   - support decrement register migration

   - various cleanups and bugfixes.

  s390:

   - Cornelia Huck passed maintainership to Janosch Frank

   - exitless interrupts for emulated devices

   - cleanup of cpuflag handling

   - kvm_stat counter improvements

   - VSIE improvements

   - mm cleanup

  x86:

   - hypervisor part of SEV

   - UMIP, RDPID, and MSR_SMI_COUNT emulation

   - paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit

   - allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more
     AVX512 features

   - show vcpu id in its anonymous inode name

   - many fixes and cleanups

   - per-VCPU MSR bitmaps (already merged through x86/pti branch)

   - stable KVM clock when nesting on Hyper-V (merged through
     x86/hyperv)"

* tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (197 commits)
  KVM: PPC: Book3S: Add MMIO emulation for VMX instructions
  KVM: PPC: Book3S HV: Branch inside feature section
  KVM: PPC: Book3S HV: Make HPT resizing work on POWER9
  KVM: PPC: Book3S HV: Fix handling of secondary HPTEG in HPT resizing code
  KVM: PPC: Book3S PR: Fix broken select due to misspelling
  KVM: x86: don't forget vcpu_put() in kvm_arch_vcpu_ioctl_set_sregs()
  KVM: PPC: Book3S PR: Fix svcpu copying with preemption enabled
  KVM: PPC: Book3S HV: Drop locks before reading guest memory
  kvm: x86: remove efer_reload entry in kvm_vcpu_stat
  KVM: x86: AMD Processor Topology Information
  x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested
  kvm: embed vcpu id to dentry of vcpu anon inode
  kvm: Map PFN-type memory regions as writable (if possible)
  x86/kvm: Make it compile on 32bit and with HYPYERVISOR_GUEST=n
  KVM: arm/arm64: Fixup userspace irqchip static key optimization
  KVM: arm/arm64: Fix userspace_irqchip_in_use counting
  KVM: arm/arm64: Fix incorrect timer_is_pending logic
  MAINTAINERS: update KVM/s390 maintainers
  MAINTAINERS: add Halil as additional vfio-ccw maintainer
  MAINTAINERS: add David as a reviewer for KVM/s390
  ...
2018-02-10 13:16:35 -08:00
Jose Ricardo Ziviani 09f984961c KVM: PPC: Book3S: Add MMIO emulation for VMX instructions
This patch provides the MMIO load/store vector indexed
X-Form emulation.

Instructions implemented:
lvx: the quadword in storage addressed by the result of EA &
0xffff_ffff_ffff_fff0 is loaded into VRT.

stvx: the contents of VRS are stored into the quadword in storage
addressed by the result of EA & 0xffff_ffff_ffff_fff0.

Reported-by: Gopesh Kumar Chaudhary <gopchaud@in.ibm.com>
Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.com>
Signed-off-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-02-09 16:51:51 +11:00
Madhavan Srinivasan 4e26bc4a4e powerpc/64: Rename soft_enabled to irq_soft_mask
Rename the paca->soft_enabled to paca->irq_soft_mask as it is no
longer used as a flag for interrupt state, but a mask.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:01 +11:00
Madhavan Srinivasan 0b63acf4a0 powerpc/64: Move set_soft_enabled() and rename
Move set_soft_enabled() from powerpc/kernel/irq.c to asm/hw_irq.c, to
encourage updates to paca->soft_enabled done via these access
function. Add "memory" clobber to hint compiler since
paca->soft_enabled memory is the target here.

Renaming it as soft_enabled_set() will make namespaces works better as
prefix than a postfix when new soft_enabled manipulation functions are
introduced.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:58 +11:00
Madhavan Srinivasan c2e480ba82 powerpc/64: Add #defines for paca->soft_enabled flags
Two #defines IRQS_ENABLED and IRQS_DISABLED are added to be used when
updating paca->soft_enabled. Replace the hardcoded values used when
updating paca->soft_enabled with IRQ_(EN|DIS)ABLED #define. No logic
change.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:56 +11:00
Paul Mackerras ded13fc11b KVM: PPC: Book3S HV: Fix migration and HPT resizing of HPT guests on radix hosts
This fixes two errors that prevent a guest using the HPT MMU from
successfully migrating to a POWER9 host in radix MMU mode, or resizing
its HPT when running on a radix host.

The first bug was that commit 8dc6cca556 ("KVM: PPC: Book3S HV:
Don't rely on host's page size information", 2017-09-11) missed two
uses of hpte_base_page_size(), one in the HPT rehashing code and
one in kvm_htab_write() (which is used on the destination side in
migrating a HPT guest).  Instead we use kvmppc_hpte_base_page_shift().
Having the shift count means that we can use left and right shifts
instead of multiplication and division in a few places.

Along the way, this adds a check in kvm_htab_write() to ensure that the
page size encoding in the incoming HPTEs is recognized, and if not
return an EINVAL error to userspace.

The second bug was that kvm_htab_write was performing some but not all
of the functions of kvmhv_setup_mmu(), resulting in the destination VM
being left in radix mode as far as the hardware is concerned.  The
simplest fix for now is make kvm_htab_write() call
kvmppc_setup_partition_table() like kvmppc_hv_setup_htab_rma() does.
In future it would be better to refactor the code more extensively
to remove the duplication.

Fixes: 8dc6cca556 ("KVM: PPC: Book3S HV: Don't rely on host's page size information")
Fixes: 7a84084c60 ("KVM: PPC: Book3S HV: Set partition table rather than SDR1 on POWER9")
Reported-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Tested-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-11-23 14:17:54 +11:00
Paul Mackerras 18c3640cef KVM: PPC: Book3S HV: Add infrastructure for running HPT guests on radix host
This sets up the machinery for switching a guest between HPT (hashed
page table) and radix MMU modes, so that in future we can run a HPT
guest on a radix host on POWER9 machines.

* The KVM_PPC_CONFIGURE_V3_MMU ioctl can now specify either HPT or
  radix mode, on a radix host.

* The KVM_CAP_PPC_MMU_HASH_V3 capability now returns 1 on POWER9
  with HV KVM on a radix host.

* The KVM_PPC_GET_SMMU_INFO returns information about the HPT MMU on a
  radix host.

* The KVM_PPC_ALLOCATE_HTAB ioctl on a radix host will switch the
  guest to HPT mode and allocate a HPT.

* For simplicity, we now allocate the rmap array for each memslot,
  even on a radix host, since it will be needed if the guest switches
  to HPT mode.

* Since we cannot yet run a HPT guest on a radix host, the KVM_RUN
  ioctl will return an EINVAL error in that case.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-11-01 15:36:28 +11:00
Paul Mackerras 3c31352460 KVM: PPC: Book3S HV: Allow userspace to set the desired SMT mode
This allows userspace to set the desired virtual SMT (simultaneous
multithreading) mode for a VM, that is, the number of VCPUs that
get assigned to each virtual core.  Previously, the virtual SMT mode
was fixed to the number of threads per subcore, and if userspace
wanted to have fewer vcpus per vcore, then it would achieve that by
using a sparse CPU numbering.  This had the disadvantage that the
vcpu numbers can get quite large, particularly for SMT1 guests on
a POWER8 with 8 threads per core.  With this patch, userspace can
set its desired virtual SMT mode and then use contiguous vcpu
numbering.

On POWER8, where the threading mode is "strict", the virtual SMT mode
must be less than or equal to the number of threads per subcore.  On
POWER9, which implements a "loose" threading mode, the virtual SMT
mode can be any power of 2 between 1 and 8, even though there is
effectively one thread per subcore, since the threads are independent
and can all be in different partitions.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-06-19 14:34:20 +10:00
Paul Mackerras fb7dcf723d Merge remote-tracking branch 'remotes/powerpc/topic/xive' into kvm-ppc-next
This merges in the powerpc topic/xive branch to bring in the code for
the in-kernel XICS interrupt controller emulation to use the new XIVE
(eXternal Interrupt Virtualization Engine) hardware in the POWER9 chip
directly, rather than via a XICS emulation in firmware.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-04-28 08:23:16 +10:00
Benjamin Herrenschmidt 5af5099385 KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller
This patch makes KVM capable of using the XIVE interrupt controller
to provide the standard PAPR "XICS" style hypercalls. It is necessary
for proper operations when the host uses XIVE natively.

This has been lightly tested on an actual system, including PCI
pass-through with a TG3 device.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Cleanup pr_xxx(), unsplit pr_xxx() strings, etc., fix build
 failures by adding KVM_XIVE which depends on KVM_XICS and XIVE, and
 adding empty stubs for the kvm_xive_xxx() routines, fixup subject,
 integrate fixes from Paul for building PR=y HV=n]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-27 21:37:29 +10:00
Alexey Kardashevskiy 121f80ba68 KVM: PPC: VFIO: Add in-kernel acceleration for VFIO
This allows the host kernel to handle H_PUT_TCE, H_PUT_TCE_INDIRECT
and H_STUFF_TCE requests targeted an IOMMU TCE table used for VFIO
without passing them to user space which saves time on switching
to user space and back.

This adds H_PUT_TCE/H_PUT_TCE_INDIRECT/H_STUFF_TCE handlers to KVM.
KVM tries to handle a TCE request in the real mode, if failed
it passes the request to the virtual mode to complete the operation.
If it a virtual mode handler fails, the request is passed to
the user space; this is not expected to happen though.

To avoid dealing with page use counters (which is tricky in real mode),
this only accelerates SPAPR TCE IOMMU v2 clients which are required
to pre-register the userspace memory. The very first TCE request will
be handled in the VFIO SPAPR TCE driver anyway as the userspace view
of the TCE table (iommu_table::it_userspace) is not allocated till
the very first mapping happens and we cannot call vmalloc in real mode.

If we fail to update a hardware IOMMU table unexpected reason, we just
clear it and move on as there is nothing really we can do about it -
for example, if we hot plug a VFIO device to a guest, existing TCE tables
will be mirrored automatically to the hardware and there is no interface
to report to the guest about possible failures.

This adds new attribute - KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE - to
the VFIO KVM device. It takes a VFIO group fd and SPAPR TCE table fd
and associates a physical IOMMU table with the SPAPR TCE table (which
is a guest view of the hardware IOMMU table). The iommu_table object
is cached and referenced so we do not have to look up for it in real mode.

This does not implement the UNSET counterpart as there is no use for it -
once the acceleration is enabled, the existing userspace won't
disable it unless a VFIO container is destroyed; this adds necessary
cleanup to the KVM_DEV_VFIO_GROUP_DEL handler.

This advertises the new KVM_CAP_SPAPR_TCE_VFIO capability to the user
space.

This adds real mode version of WARN_ON_ONCE() as the generic version
causes problems with rcu_sched. Since we testing what vmalloc_to_phys()
returns in the code, this also adds a check for already existing
vmalloc_to_phys() call in kvmppc_rm_h_put_tce_indirect().

This finally makes use of vfio_external_user_iommu_id() which was
introduced quite some time ago and was considered for removal.

Tests show that this patch increases transmission speed from 220MB/s
to 750..1020MB/s on 10Gb network (Chelsea CXGB3 10Gb ethernet card).

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-04-20 11:39:26 +10:00
Alexey Kardashevskiy b1af23d836 KVM: PPC: iommu: Unify TCE checking
This reworks helpers for checking TCE update parameters in way they
can be used in KVM.

This should cause no behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-04-20 11:39:21 +10:00
Alexey Kardashevskiy 503bfcbe18 KVM: PPC: Pass kvm* to kvmppc_find_table()
The guest view TCE tables are per KVM anyway (not per VCPU) so pass kvm*
there. This will be used in the following patches where we will be
attaching VFIO containers to LIOBNs via ioctl() to KVM (rather than
to VCPU).

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-04-20 11:39:12 +10:00
Bin Lu 6f63e81bda KVM: PPC: Book3S: Add MMIO emulation for FP and VSX instructions
This patch provides the MMIO load/store emulation for instructions
of 'double & vector unsigned char & vector signed char & vector
unsigned short & vector signed short & vector unsigned int & vector
signed int & vector double '.

The instructions that this adds emulation for are:

- ldx, ldux, lwax,
- lfs, lfsx, lfsu, lfsux, lfd, lfdx, lfdu, lfdux,
- stfs, stfsx, stfsu, stfsux, stfd, stfdx, stfdu, stfdux, stfiwx,
- lxsdx, lxsspx, lxsiwax, lxsiwzx, lxvd2x, lxvw4x, lxvdsx,
- stxsdx, stxsspx, stxsiwx, stxvd2x, stxvw4x

[paulus@ozlabs.org - some cleanups, fixes and rework, make it
 compile for Book E, fix build when PR KVM is built in]

Signed-off-by: Bin Lu <lblulb@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-04-20 11:36:41 +10:00
Paul Mackerras 307d927967 KVM: PPC: Provide functions for queueing up FP/VEC/VSX unavailable interrupts
This provides functions that can be used for generating interrupts
indicating that a given functional unit (floating point, vector, or
VSX) is unavailable.  These functions will be used in instruction
emulation code.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-04-20 10:39:50 +10:00
Benjamin Herrenschmidt d381d7caf8 powerpc: Consolidate variants of real-mode MMIOs
We have all sort of variants of MMIO accessors for the real mode
instructions. This creates a clean set of accessors based on
Linux normal naming conventions, replacing all occurrences of
the old ones in the tree.

I have purposefully removed the "out/in" variants in favor of
only including __raw variants. Any code using these is already
pretty much hand tuned to operate in a very specific environment.
I've fixed up the 2 users (only one of them actually needed
a barrier in the first place).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-10 21:43:16 +10:00
Benjamin Herrenschmidt f50d6bd344 powerpc/kvm: Remove obsolete kvm_vm_ioctl_xics_irq declaration
The function doesn't exist anymore

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-10 21:43:16 +10:00
Benjamin Herrenschmidt 936774cd3f powerpc/kvm: Make kvmppc_xics_create_icp static
It's only used within the same file it's defined

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-10 21:43:15 +10:00
David Gibson 5e9859699a KVM: PPC: Book3S HV: Outline of KVM-HV HPT resizing implementation
This adds a not yet working outline of the HPT resizing PAPR
extension.  Specifically it adds the necessary ioctl() functions,
their basic steps, the work function which will handle preparation for
the resize, and synchronization between these, the guest page fault
path and guest HPT update path.

The actual guts of the implementation isn't here yet, so for now the
calls will always fail.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-01-31 21:59:56 +11:00
David Gibson f98a8bf9ee KVM: PPC: Book3S HV: Allow KVM_PPC_ALLOCATE_HTAB ioctl() to change HPT size
The KVM_PPC_ALLOCATE_HTAB ioctl() is used to set the size of hashed page
table (HPT) that userspace expects a guest VM to have, and is also used to
clear that HPT when necessary (e.g. guest reboot).

At present, once the ioctl() is called for the first time, the HPT size can
never be changed thereafter - it will be cleared but always sized as from
the first call.

With upcoming HPT resize implementation, we're going to need to allow
userspace to resize the HPT at reset (to change it back to the default size
if the guest changed it).

So, we need to allow this ioctl() to change the HPT size.

This patch also updates Documentation/virtual/kvm/api.txt to reflect
the new behaviour.  In fact the documentation was already slightly
incorrect since 572abd5 "KVM: PPC: Book3S HV: Don't fall back to
smaller HPT size in allocation ioctl"

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-01-31 21:59:45 +11:00
David Gibson aae0777f1e KVM: PPC: Book3S HV: Split HPT allocation from activation
Currently, kvmppc_alloc_hpt() both allocates a new hashed page table (HPT)
and sets it up as the active page table for a VM.  For the upcoming HPT
resize implementation we're going to want to allocate HPTs separately from
activating them.

So, split the allocation itself out into kvmppc_allocate_hpt() and perform
the activation with a new kvmppc_set_hpt() function.  Likewise we split
kvmppc_free_hpt(), which just frees the HPT, from kvmppc_release_hpt()
which unsets it as an active HPT, then frees it.

We also move the logic to fall back to smaller HPT sizes if the first try
fails into the single caller which used that behaviour,
kvmppc_hv_setup_htab_rma().  This introduces a slight semantic change, in
that previously if the initial attempt at CMA allocation failed, we would
fall back to attempting smaller sizes with the page allocator.  Now, we
try first CMA, then the page allocator at each size.  As far as I can tell
this change should be harmless.

To match, we make kvmppc_free_hpt() just free the actual HPT itself.  The
call to kvmppc_free_lpid() that was there, we move to the single caller.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-01-31 21:59:39 +11:00
David Gibson db9a290d9c KVM: PPC: Book3S HV: Rename kvm_alloc_hpt() for clarity
The difference between kvm_alloc_hpt() and kvmppc_alloc_hpt() is not at
all obvious from the name.  In practice kvmppc_alloc_hpt() allocates an HPT
by whatever means, and calls kvm_alloc_hpt() which will attempt to allocate
it with CMA only.

To make this less confusing, rename kvm_alloc_hpt() to kvm_alloc_hpt_cma().
Similarly, kvm_release_hpt() is renamed kvm_free_hpt_cma().

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-01-31 21:59:23 +11:00
Paul Mackerras c927013227 KVM: PPC: Book3S HV: Add userspace interfaces for POWER9 MMU
This adds two capabilities and two ioctls to allow userspace to
find out about and configure the POWER9 MMU in a guest.  The two
capabilities tell userspace whether KVM can support a guest using
the radix MMU, or using the hashed page table (HPT) MMU with a
process table and segment tables.  (Note that the MMUs in the
POWER9 processor cores do not use the process and segment tables
when in HPT mode, but the nest MMU does).

The KVM_PPC_CONFIGURE_V3_MMU ioctl allows userspace to specify
whether a guest will use the radix MMU or the HPT MMU, and to
specify the size and location (in guest space) of the process
table.

The KVM_PPC_GET_RMMU_INFO ioctl gives userspace information about
the radix MMU.  It returns a list of supported radix tree geometries
(base page size and number of bits indexed at each level of the
radix tree) and the encoding used to specify the various page
sizes for the TLB invalidate entry instruction.

Initially, both capabilities return 0 and the ioctls return -EINVAL,
until the necessary infrastructure for them to operate correctly
is added.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:47 +11:00
Paul Mackerras e34af78490 KVM: PPC: Book3S: Move prototypes for KVM functions into kvm_ppc.h
This moves the prototypes for functions that are only called from
assembler code out of asm/asm-prototypes.h into asm/kvm_ppc.h.
The prototypes were added in commit ebe4535fbe ("KVM: PPC:
Book3S HV: sparse: prototypes for functions called from assembler",
2016-10-10), but given that the functions are KVM functions,
having them in a KVM header will be better for long-term
maintenance.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-12-01 14:03:46 +11:00
Paul Mackerras f725758b89 KVM: PPC: Book3S HV: Use OPAL XICS emulation on POWER9
POWER9 includes a new interrupt controller, called XIVE, which is
quite different from the XICS interrupt controller on POWER7 and
POWER8 machines.  KVM-HV accesses the XICS directly in several places
in order to send and clear IPIs and handle interrupts from PCI
devices being passed through to the guest.

In order to make the transition to XIVE easier, OPAL firmware will
include an emulation of XICS on top of XIVE.  Access to the emulated
XICS is via OPAL calls.  The one complication is that the EOI
(end-of-interrupt) function can now return a value indicating that
another interrupt is pending; in this case, the XIVE will not signal
an interrupt in hardware to the CPU, and software is supposed to
acknowledge the new interrupt without waiting for another interrupt
to be delivered in hardware.

This adapts KVM-HV to use the OPAL calls on machines where there is
no XICS hardware.  When there is no XICS, we look for a device-tree
node with "ibm,opal-intc" in its compatible property, which is how
OPAL indicates that it provides XICS emulation.

In order to handle the EOI return value, kvmppc_read_intr() has
become kvmppc_read_one_intr(), with a boolean variable passed by
reference which can be set by the EOI functions to indicate that
another interrupt is pending.  The new kvmppc_read_intr() keeps
calling kvmppc_read_one_intr() until there are no more interrupts
to process.  The return value from kvmppc_read_intr() is the
largest non-zero value of the returns from kvmppc_read_one_intr().

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-11-24 09:24:23 +11:00
Paul Mackerras 5d375199ea KVM: PPC: Book3S HV: Set server for passed-through interrupts
When a guest has a PCI pass-through device with an interrupt, it
will direct the interrupt to a particular guest VCPU.  In fact the
physical interrupt might arrive on any CPU, and then get
delivered to the target VCPU in the emulated XICS (guest interrupt
controller), and eventually delivered to the target VCPU.

Now that we have code to handle device interrupts in real mode
without exiting to the host kernel, there is an advantage to having
the device interrupt arrive on the same sub(core) as the target
VCPU is running on.  In this situation, the interrupt can be
delivered to the target VCPU without any exit to the host kernel
(using a hypervisor doorbell interrupt between threads if
necessary).

This patch aims to get passed-through device interrupts arriving
on the correct core by setting the interrupt server in the real
hardware XICS for the interrupt to the first thread in the (sub)core
where its target VCPU is running.  We do this in the real-mode H_EOI
code because the H_EOI handler already needs to look at the
emulated ICS state for the interrupt (whereas the H_XIRR handler
doesn't), and we know we are running in the target VCPU context
at that point.

We set the server CPU in hardware using an OPAL call, regardless of
what the IRQ affinity mask for the interrupt says, and without
updating the affinity mask.  This amounts to saying that when an
interrupt is passed through to a guest, as a matter of policy we
allow the guest's affinity for the interrupt to override the host's.

This is inspired by an earlier patch from Suresh Warrier, although
none of this code came from that earlier patch.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:28 +10:00
Suresh Warrier 644abbb254 KVM: PPC: Book3S HV: Tunable to disable KVM IRQ bypass
Add a  module parameter kvm_irq_bypass for kvm_hv.ko to
disable IRQ bypass for passthrough interrupts. The default
value of this tunable is 1 - that is enable the feature.

Since the tunable is used by built-in kernel code, we use
the module_param_cb macro to achieve this.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:18 +10:00
Suresh Warrier f7af5209b8 KVM: PPC: Book3S HV: Complete passthrough interrupt in host
In existing real mode ICP code, when updating the virtual ICP
state, if there is a required action that cannot be completely
handled in real mode, as for instance, a VCPU needs to be woken
up, flags are set in the ICP to indicate the required action.
This is checked when returning from hypercalls to decide whether
the call needs switch back to the host where the action can be
performed in virtual mode. Note that if h_ipi_redirect is enabled,
real mode code will first try to message a free host CPU to
complete this job instead of returning the host to do it ourselves.

Currently, the real mode PCI passthrough interrupt handling code
checks if any of these flags are set and simply returns to the host.
This is not good enough as the trap value (0x500) is treated as an
external interrupt by the host code. It is only when the trap value
is a hypercall that the host code searches for and acts on unfinished
work by calling kvmppc_xics_rm_complete.

This patch introduces a special trap BOOK3S_INTERRUPT_HV_RM_HARD
which is returned by KVM if there is unfinished business to be
completed in host virtual mode after handling a PCI passthrough
interrupt. The host checks for this special interrupt condition
and calls into the kvmppc_xics_rm_complete, which is made an
exported function for this reason.

[paulus@ozlabs.org - moved logic to set r12 to BOOK3S_INTERRUPT_HV_RM_HARD
 in book3s_hv_rmhandlers.S into the end of kvmppc_check_wake_reason.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:12:07 +10:00
Suresh Warrier e3c13e56a4 KVM: PPC: Book3S HV: Handle passthrough interrupts in guest
Currently, KVM switches back to the host to handle any external
interrupt (when the interrupt is received while running in the
guest). This patch updates real-mode KVM to check if an interrupt
is generated by a passthrough adapter that is owned by this guest.
If so, the real mode KVM will directly inject the corresponding
virtual interrupt to the guest VCPU's ICS and also EOI the interrupt
in hardware. In short, the interrupt is handled entirely in real
mode in the guest context without switching back to the host.

In some rare cases, the interrupt cannot be completely handled in
real mode, for instance, a VCPU that is sleeping needs to be woken
up. In this case, KVM simply switches back to the host with trap
reason set to 0x500. This works, but it is clearly not very efficient.
A following patch will distinguish this case and handle it
correctly in the host. Note that we can use the existing
check_too_hard() routine even though we are not in a hypercall to
determine if there is unfinished business that needs to be
completed in host virtual mode.

The patch assumes that the mapping between hardware interrupt IRQ
and virtual IRQ to be injected to the guest already exists for the
PCI passthrough interrupts that need to be handled in real mode.
If the mapping does not exist, KVM falls back to the default
existing behavior.

The KVM real mode code reads mappings from the mapped array in the
passthrough IRQ map without taking any lock.  We carefully order the
loads and stores of the fields in the kvmppc_irq_map data structure
using memory barriers to avoid an inconsistent mapping being seen by
the reader. Thus, although it is possible to miss a map entry, it is
not possible to read a stale value.

[paulus@ozlabs.org - get irq_chip from irq_map rather than pimap,
 pulled out powernv eoi change into a separate patch, made
 kvmppc_read_intr get the vcpu from the paca rather than being
 passed in, rewrote the logic at the end of kvmppc_read_intr to
 avoid deep indentation, simplified logic in book3s_hv_rmhandlers.S
 since we were always restoring SRR0/1 anyway, get rid of the cached
 array (just use the mapped array), removed the kick_all_cpus_sync()
 call, clear saved_xirr PACA field when we handle the interrupt in
 real mode, fix compilation with CONFIG_KVM_XICS=n.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-12 10:11:00 +10:00
Suresh Warrier 8daaafc88b KVM: PPC: Book3S HV: Introduce kvmppc_passthru_irqmap
This patch introduces an IRQ mapping structure, the
kvmppc_passthru_irqmap structure that is to be used
to map the real hardware IRQ in the host with the virtual
hardware IRQ (gsi) that is injected into a guest by KVM for
passthrough adapters.

Currently, we assume a separate IRQ mapping structure for
each guest. Each kvmppc_passthru_irqmap has a mapping arrays,
containing all defined real<->virtual IRQs.

[paulus@ozlabs.org - removed irq_chip field from struct
 kvmppc_passthru_irqmap; changed parameter for
 kvmppc_get_passthru_irqmap from struct kvm_vcpu * to struct
 kvm *, removed small cached array.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-09 16:26:19 +10:00
Suresh Warrier 9576730d0e KVM: PPC: select IRQ_BYPASS_MANAGER
Select IRQ_BYPASS_MANAGER for PPC when CONFIG_KVM is set.
Add the PPC producer functions for add and del producer.

[paulus@ozlabs.org - Moved new functions from book3s.c to powerpc.c
 so booke compiles; added kvm_arch_has_irq_bypass implementation.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-09 16:26:19 +10:00
Alexey Kardashevskiy 58ded4201f KVM: PPC: Add support for 64bit TCE windows
The existing KVM_CREATE_SPAPR_TCE only supports 32bit windows which is not
enough for directly mapped windows as the guest can get more than 4GB.

This adds KVM_CREATE_SPAPR_TCE_64 ioctl and advertises it
via KVM_CAP_SPAPR_TCE_64 capability. The table size is checked against
the locked memory limit.

Since 64bit windows are to support Dynamic DMA windows (DDW), let's add
@bus_offset and @page_shift which are also required by DDW.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2016-03-02 09:56:50 +11:00
Suresh E. Warrier 520fe9c607 KVM: PPC: Book3S HV: Add tunable to control H_IPI redirection
Redirecting the wakeup of a VCPU from the H_IPI hypercall to
a core running in the host is usually a good idea, most workloads
seemed to benefit. However, in one heavily interrupt-driven SMT1
workload, some regression was observed. This patch adds a kvm_hv
module parameter called h_ipi_redirect to control this feature.

The default value for this tunable is 1 - that is enable the feature.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2016-02-29 16:25:06 +11:00
Suresh Warrier 0c2a660624 KVM: PPC: Book3S HV: Host side kick VCPU when poked by real-mode KVM
This patch adds the support for the kick VCPU operation for
kvmppc_host_rm_ops. The kvmppc_xics_ipi_action() function
provides the function to be invoked for a host side operation
when poked by the real mode KVM. This is initiated by KVM by
sending an IPI to any free host core.

KVM real mode must set the rm_action to XICS_RM_KICK_VCPU and
rm_data to point to the VCPU to be woken up before sending the IPI.
Note that we have allocated one kvmppc_host_rm_core structure
per core. The above values need to be set in the structure
corresponding to the core to which the IPI will be sent.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2016-02-29 16:25:06 +11:00
Suresh Warrier 79b6c247e9 KVM: PPC: Book3S HV: Host-side RM data structures
This patch defines the data structures to support the setting up
of host side operations while running in real mode in the guest,
and also the functions to allocate and free it.

The operations are for now limited to virtual XICS operations.
Currently, we have only defined one operation in the data
structure:
         - Wake up a VCPU sleeping in the host when it
           receives a virtual interrupt

The operations are assigned at the core level because PowerKVM
requires that the host run in SMT off mode. For each core,
we will need to manage its state atomically - where the state
is defined by:
1. Is the core running in the host?
2. Is there a Real Mode (RM) operation pending on the host?

Currently, core state is only managed at the whole-core level
even when the system is in split-core mode. This just limits
the number of free or "available" cores in the host to perform
any host-side operations.

The kvmppc_host_rm_core.rm_data allows any data to be passed by
KVM in real mode to the host core along with the operation to
be performed.

The kvmppc_host_rm_ops structure is allocated the very first time
a guest VM is started. Initial core state is also set - all online
cores are in the host. This structure is never deleted, not even
when there are no active guests. However, it needs to be freed
when the module is unloaded because the kvmppc_host_rm_ops_hv
can contain function pointers to kvm-hv.ko functions for the
different supported host operations.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2016-02-29 16:25:06 +11:00
Alexey Kardashevskiy d3695aa4f4 KVM: PPC: Add support for multiple-TCE hcalls
This adds real and virtual mode handlers for the H_PUT_TCE_INDIRECT and
H_STUFF_TCE hypercalls for user space emulated devices such as IBMVIO
devices or emulated PCI. These calls allow adding multiple entries
(up to 512) into the TCE table in one call which saves time on
transition between kernel and user space.

The current implementation of kvmppc_h_stuff_tce() allows it to be
executed in both real and virtual modes so there is one helper.
The kvmppc_rm_h_put_tce_indirect() needs to translate the guest address
to the host address and since the translation is different, there are
2 helpers - one for each mode.

This implements the KVM_CAP_PPC_MULTITCE capability. When present,
the kernel will try handling H_PUT_TCE_INDIRECT and H_STUFF_TCE if these
are enabled by the userspace via KVM_CAP_PPC_ENABLE_HCALL.
If they can not be handled by the kernel, they are passed on to
the user space. The user space still has to have an implementation
for these.

Both HV and PR-syle KVM are supported.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2016-02-16 13:44:26 +11:00
Alexey Kardashevskiy 5ee7af1864 KVM: PPC: Move reusable bits of H_PUT_TCE handler to helpers
Upcoming multi-tce support (H_PUT_TCE_INDIRECT/H_STUFF_TCE hypercalls)
will validate TCE (not to have unexpected bits) and IO address
(to be within the DMA window boundaries).

This introduces helpers to validate TCE and IO address. The helpers are
exported as they compile into vmlinux (to work in realmode) and will be
used later by KVM kernel module in virtual mode.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2016-02-16 13:44:26 +11:00
Dan Williams ba049e93ae kvm: rename pfn_t to kvm_pfn_t
To date, we have implemented two I/O usage models for persistent memory,
PMEM (a persistent "ram disk") and DAX (mmap persistent memory into
userspace).  This series adds a third, DAX-GUP, that allows DAX mappings
to be the target of direct-i/o.  It allows userspace to coordinate
DMA/RDMA from/to persistent memory.

The implementation leverages the ZONE_DEVICE mm-zone that went into
4.3-rc1 (also discussed at kernel summit) to flag pages that are owned
and dynamically mapped by a device driver.  The pmem driver, after
mapping a persistent memory range into the system memmap via
devm_memremap_pages(), arranges for DAX to distinguish pfn-only versus
page-backed pmem-pfns via flags in the new pfn_t type.

The DAX code, upon seeing a PFN_DEV+PFN_MAP flagged pfn, flags the
resulting pte(s) inserted into the process page tables with a new
_PAGE_DEVMAP flag.  Later, when get_user_pages() is walking ptes it keys
off _PAGE_DEVMAP to pin the device hosting the page range active.
Finally, get_page() and put_page() are modified to take references
against the device driver established page mapping.

Finally, this need for "struct page" for persistent memory requires
memory capacity to store the memmap array.  Given the memmap array for a
large pool of persistent may exhaust available DRAM introduce a
mechanism to allocate the memmap from persistent memory.  The new
"struct vmem_altmap *" parameter to devm_memremap_pages() enables
arch_add_memory() to use reserved pmem capacity rather than the page
allocator.

This patch (of 18):

The core has developed a need for a "pfn_t" type [1].  Move the existing
pfn_t in KVM to kvm_pfn_t [2].

[1]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002199.html
[2]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002218.html

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Paolo Bonzini f36f3f2846 KVM: add "new" argument to kvm_arch_commit_memory_region
This lets the function access the new memory slot without going through
kvm_memslots and id_to_memslot.  It will simplify the code when more
than one address space will be supported.

Unfortunately, the "const"ness of the new argument must be casted
away in two places.  Fixing KVM to accept const struct kvm_memory_slot
pointers would require modifications in pretty much all architectures,
and is left for later.

Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-28 10:42:58 +02:00