We can disable a THP split or a hugepage collapse by disabling irq.
We do send IPI to all the cpus in the early part of split/collapse,
and disabling local irq ensure we don't make progress with
split/collapse. If the THP is getting split we return NULL from
find_linux_pte_or_hugepte(). For all the current callers it should be ok.
We need to be careful if we want to use returned pte_t pointer outside
the irq disabled region. W.r.t to THP split, the pfn remains the same,
but then a hugepage collapse will result in a pfn change. There are
few steps we can take to avoid a hugepage collapse.One way is to take page
reference inside the irq disable region. Other option is to take
mmap_sem so that a parallel collapse will not happen. We can also
disable collapse by taking pmd_lock. Another method used by kvm
subsystem is to check whether we had a mmu_notifer update in between
using mmu_notifier_retry().
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch remove helpers which we had used only once in the code.
Limiting page table walk variants help in ensuring that we won't
end up with code walking page table with wrong assumptions.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
pte can get updated from other CPUs as part of multiple activities
like THP split, huge page collapse, unmap. We need to make sure we
don't reload the pte value again and again for different checks.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch fix spelling typo in printk and Kconfig within
various part of kernel sources.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
New awesome things in this release:
- E500: e6500 core support
- E500: guest and remote debug support
- Book3S: remote sw breakpoint support
- Book3S: HV: Minor bugfixes
Alexander Graf (1):
KVM: PPC: Pass enum to kvmppc_get_last_inst
Bharat Bhushan (8):
KVM: PPC: BOOKE: allow debug interrupt at "debug level"
KVM: PPC: BOOKE : Emulate rfdi instruction
KVM: PPC: BOOKE: Allow guest to change MSR_DE
KVM: PPC: BOOKE: Clear guest dbsr in userspace exit KVM_EXIT_DEBUG
KVM: PPC: BOOKE: Guest and hardware visible debug registers are same
KVM: PPC: BOOKE: Add one reg interface for DBSR
KVM: PPC: BOOKE: Add one_reg documentation of SPRG9 and DBSR
KVM: PPC: BOOKE: Emulate debug registers and exception
Madhavan Srinivasan (2):
powerpc/kvm: support to handle sw breakpoint
powerpc/kvm: common sw breakpoint instr across ppc
Michael Neuling (1):
KVM: PPC: Book3S HV: Add register name when loading toc
Mihai Caraman (10):
powerpc/booke: Restrict SPE exception handlers to e200/e500 cores
powerpc/booke: Revert SPE/AltiVec common defines for interrupt numbers
KVM: PPC: Book3E: Increase FPU laziness
KVM: PPC: Book3e: Add AltiVec support
KVM: PPC: Make ONE_REG powerpc generic
KVM: PPC: Move ONE_REG AltiVec support to powerpc
KVM: PPC: Remove the tasklet used by the hrtimer
KVM: PPC: Remove shared defines for SPE and AltiVec interrupts
KVM: PPC: e500mc: Add support for single threaded vcpus on e6500 core
KVM: PPC: Book3E: Enable e6500 core
Paul Mackerras (2):
KVM: PPC: Book3S HV: Increase timeout for grabbing secondary threads
KVM: PPC: Book3S HV: Only accept host PVR value for guest PVR
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Merge tag 'signed-kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvm-next
Patch queue for ppc - 2014-09-24
New awesome things in this release:
- E500: e6500 core support
- E500: guest and remote debug support
- Book3S: remote sw breakpoint support
- Book3S: HV: Minor bugfixes
Alexander Graf (1):
KVM: PPC: Pass enum to kvmppc_get_last_inst
Bharat Bhushan (8):
KVM: PPC: BOOKE: allow debug interrupt at "debug level"
KVM: PPC: BOOKE : Emulate rfdi instruction
KVM: PPC: BOOKE: Allow guest to change MSR_DE
KVM: PPC: BOOKE: Clear guest dbsr in userspace exit KVM_EXIT_DEBUG
KVM: PPC: BOOKE: Guest and hardware visible debug registers are same
KVM: PPC: BOOKE: Add one reg interface for DBSR
KVM: PPC: BOOKE: Add one_reg documentation of SPRG9 and DBSR
KVM: PPC: BOOKE: Emulate debug registers and exception
Madhavan Srinivasan (2):
powerpc/kvm: support to handle sw breakpoint
powerpc/kvm: common sw breakpoint instr across ppc
Michael Neuling (1):
KVM: PPC: Book3S HV: Add register name when loading toc
Mihai Caraman (10):
powerpc/booke: Restrict SPE exception handlers to e200/e500 cores
powerpc/booke: Revert SPE/AltiVec common defines for interrupt numbers
KVM: PPC: Book3E: Increase FPU laziness
KVM: PPC: Book3e: Add AltiVec support
KVM: PPC: Make ONE_REG powerpc generic
KVM: PPC: Move ONE_REG AltiVec support to powerpc
KVM: PPC: Remove the tasklet used by the hrtimer
KVM: PPC: Remove shared defines for SPE and AltiVec interrupts
KVM: PPC: e500mc: Add support for single threaded vcpus on e6500 core
KVM: PPC: Book3E: Enable e6500 core
Paul Mackerras (2):
KVM: PPC: Book3S HV: Increase timeout for grabbing secondary threads
KVM: PPC: Book3S HV: Only accept host PVR value for guest PVR
1. We were calling clear_flush_young_notify in unmap_one, but we are
within an mmu notifier invalidate range scope. The spte exists no more
(due to range_start) and the accessed bit info has already been
propagated (due to kvm_pfn_set_accessed). Simply call
clear_flush_young.
2. We clear_flush_young on a primary MMU PMD, but this may be mapped
as a collection of PTEs by the secondary MMU (e.g. during log-dirty).
This required expanding the interface of the clear_flush_young mmu
notifier, so a lot of code has been trivially touched.
3. In the absence of shadow_accessed_mask (e.g. EPT A bit), we emulate
the access bit by blowing the spte. This requires proper synchronizing
with MMU notifier consumers, like every other removal of spte's does.
Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
ePAPR represents hardware threads as cpu node properties in device tree.
So with existing QEMU, hardware threads are simply exposed as vcpus with
one hardware thread.
The e6500 core shares TLBs between hardware threads. Without tlb write
conditional instruction, the Linux kernel uses per core mechanisms to
protect against duplicate TLB entries.
The guest is unable to detect real siblings threads, so it can't use the
TLB protection mechanism. An alternative solution is to use the hypervisor
to allocate different lpids to guest's vcpus that runs simultaneous on real
siblings threads. On systems with two threads per core this patch halves
the size of the lpid pool that the allocator sees and use two lpids per VM.
Use even numbers to speedup vcpu lpid computation with consecutive lpids
per VM: vm1 will use lpids 2 and 3, vm2 lpids 4 and 5, and so on.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
[agraf: fix spelling]
Signed-off-by: Alexander Graf <agraf@suse.de>
Highlights in this release include:
- BookE: Rework instruction fetch, not racy anymore now
- BookE HV: Fix ONE_REG accessors for some in-hardware registers
- Book3S: Good number of LE host fixes, enable HV on LE
- Book3S: Some misc bug fixes
- Book3S HV: Add in-guest debug support
- Book3S HV: Preload cache lines on context switch
- Remove 440 support
Alexander Graf (31):
KVM: PPC: Book3s PR: Disable AIL mode with OPAL
KVM: PPC: Book3s HV: Fix tlbie compile error
KVM: PPC: Book3S PR: Handle hyp doorbell exits
KVM: PPC: Book3S PR: Fix ABIv2 on LE
KVM: PPC: Book3S PR: Fix sparse endian checks
PPC: Add asm helpers for BE 32bit load/store
KVM: PPC: Book3S HV: Make HTAB code LE host aware
KVM: PPC: Book3S HV: Access guest VPA in BE
KVM: PPC: Book3S HV: Access host lppaca and shadow slb in BE
KVM: PPC: Book3S HV: Access XICS in BE
KVM: PPC: Book3S HV: Fix ABIv2 on LE
KVM: PPC: Book3S HV: Enable for little endian hosts
KVM: PPC: Book3S: Move vcore definition to end of kvm_arch struct
KVM: PPC: Deflect page write faults properly in kvmppc_st
KVM: PPC: Book3S: Stop PTE lookup on write errors
KVM: PPC: Book3S: Add hack for split real mode
KVM: PPC: Book3S: Make magic page properly 4k mappable
KVM: PPC: Remove 440 support
KVM: Rename and add argument to check_extension
KVM: Allow KVM_CHECK_EXTENSION on the vm fd
KVM: PPC: Book3S: Provide different CAPs based on HV or PR mode
KVM: PPC: Implement kvmppc_xlate for all targets
KVM: PPC: Move kvmppc_ld/st to common code
KVM: PPC: Remove kvmppc_bad_hva()
KVM: PPC: Use kvm_read_guest in kvmppc_ld
KVM: PPC: Handle magic page in kvmppc_ld/st
KVM: PPC: Separate loadstore emulation from priv emulation
KVM: PPC: Expose helper functions for data/inst faults
KVM: PPC: Remove DCR handling
KVM: PPC: HV: Remove generic instruction emulation
KVM: PPC: PR: Handle FSCR feature deselects
Alexey Kardashevskiy (1):
KVM: PPC: Book3S: Fix LPCR one_reg interface
Aneesh Kumar K.V (4):
KVM: PPC: BOOK3S: PR: Fix PURR and SPURR emulation
KVM: PPC: BOOK3S: PR: Emulate virtual timebase register
KVM: PPC: BOOK3S: PR: Emulate instruction counter
KVM: PPC: BOOK3S: HV: Update compute_tlbie_rb to handle 16MB base page
Anton Blanchard (2):
KVM: PPC: Book3S HV: Fix ABIv2 indirect branch issue
KVM: PPC: Assembly functions exported to modules need _GLOBAL_TOC()
Bharat Bhushan (10):
kvm: ppc: bookehv: Added wrapper macros for shadow registers
kvm: ppc: booke: Use the shared struct helpers of SRR0 and SRR1
kvm: ppc: booke: Use the shared struct helpers of SPRN_DEAR
kvm: ppc: booke: Add shared struct helpers of SPRN_ESR
kvm: ppc: booke: Use the shared struct helpers for SPRN_SPRG0-7
kvm: ppc: Add SPRN_EPR get helper function
kvm: ppc: bookehv: Save restore SPRN_SPRG9 on guest entry exit
KVM: PPC: Booke-hv: Add one reg interface for SPRG9
KVM: PPC: Remove comment saying SPRG1 is used for vcpu pointer
KVM: PPC: BOOKEHV: rename e500hv_spr to bookehv_spr
Michael Neuling (1):
KVM: PPC: Book3S HV: Add H_SET_MODE hcall handling
Mihai Caraman (8):
KVM: PPC: e500mc: Enhance tlb invalidation condition on vcpu schedule
KVM: PPC: e500: Fix default tlb for victim hint
KVM: PPC: e500: Emulate power management control SPR
KVM: PPC: e500mc: Revert "add load inst fixup"
KVM: PPC: Book3e: Add TLBSEL/TSIZE defines for MAS0/1
KVM: PPC: Book3s: Remove kvmppc_read_inst() function
KVM: PPC: Allow kvmppc_get_last_inst() to fail
KVM: PPC: Bookehv: Get vcpu's last instruction for emulation
Paul Mackerras (4):
KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handling
KVM: PPC: Book3S: Allow only implemented hcalls to be enabled or disabled
KVM: PPC: Book3S PR: Take SRCU read lock around RTAS kvm_read_guest() call
KVM: PPC: Book3S: Make kvmppc_ld return a more accurate error indication
Stewart Smith (2):
Split out struct kvmppc_vcore creation to separate function
Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8
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Merge tag 'signed-kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvm
Patch queue for ppc - 2014-08-01
Highlights in this release include:
- BookE: Rework instruction fetch, not racy anymore now
- BookE HV: Fix ONE_REG accessors for some in-hardware registers
- Book3S: Good number of LE host fixes, enable HV on LE
- Book3S: Some misc bug fixes
- Book3S HV: Add in-guest debug support
- Book3S HV: Preload cache lines on context switch
- Remove 440 support
Alexander Graf (31):
KVM: PPC: Book3s PR: Disable AIL mode with OPAL
KVM: PPC: Book3s HV: Fix tlbie compile error
KVM: PPC: Book3S PR: Handle hyp doorbell exits
KVM: PPC: Book3S PR: Fix ABIv2 on LE
KVM: PPC: Book3S PR: Fix sparse endian checks
PPC: Add asm helpers for BE 32bit load/store
KVM: PPC: Book3S HV: Make HTAB code LE host aware
KVM: PPC: Book3S HV: Access guest VPA in BE
KVM: PPC: Book3S HV: Access host lppaca and shadow slb in BE
KVM: PPC: Book3S HV: Access XICS in BE
KVM: PPC: Book3S HV: Fix ABIv2 on LE
KVM: PPC: Book3S HV: Enable for little endian hosts
KVM: PPC: Book3S: Move vcore definition to end of kvm_arch struct
KVM: PPC: Deflect page write faults properly in kvmppc_st
KVM: PPC: Book3S: Stop PTE lookup on write errors
KVM: PPC: Book3S: Add hack for split real mode
KVM: PPC: Book3S: Make magic page properly 4k mappable
KVM: PPC: Remove 440 support
KVM: Rename and add argument to check_extension
KVM: Allow KVM_CHECK_EXTENSION on the vm fd
KVM: PPC: Book3S: Provide different CAPs based on HV or PR mode
KVM: PPC: Implement kvmppc_xlate for all targets
KVM: PPC: Move kvmppc_ld/st to common code
KVM: PPC: Remove kvmppc_bad_hva()
KVM: PPC: Use kvm_read_guest in kvmppc_ld
KVM: PPC: Handle magic page in kvmppc_ld/st
KVM: PPC: Separate loadstore emulation from priv emulation
KVM: PPC: Expose helper functions for data/inst faults
KVM: PPC: Remove DCR handling
KVM: PPC: HV: Remove generic instruction emulation
KVM: PPC: PR: Handle FSCR feature deselects
Alexey Kardashevskiy (1):
KVM: PPC: Book3S: Fix LPCR one_reg interface
Aneesh Kumar K.V (4):
KVM: PPC: BOOK3S: PR: Fix PURR and SPURR emulation
KVM: PPC: BOOK3S: PR: Emulate virtual timebase register
KVM: PPC: BOOK3S: PR: Emulate instruction counter
KVM: PPC: BOOK3S: HV: Update compute_tlbie_rb to handle 16MB base page
Anton Blanchard (2):
KVM: PPC: Book3S HV: Fix ABIv2 indirect branch issue
KVM: PPC: Assembly functions exported to modules need _GLOBAL_TOC()
Bharat Bhushan (10):
kvm: ppc: bookehv: Added wrapper macros for shadow registers
kvm: ppc: booke: Use the shared struct helpers of SRR0 and SRR1
kvm: ppc: booke: Use the shared struct helpers of SPRN_DEAR
kvm: ppc: booke: Add shared struct helpers of SPRN_ESR
kvm: ppc: booke: Use the shared struct helpers for SPRN_SPRG0-7
kvm: ppc: Add SPRN_EPR get helper function
kvm: ppc: bookehv: Save restore SPRN_SPRG9 on guest entry exit
KVM: PPC: Booke-hv: Add one reg interface for SPRG9
KVM: PPC: Remove comment saying SPRG1 is used for vcpu pointer
KVM: PPC: BOOKEHV: rename e500hv_spr to bookehv_spr
Michael Neuling (1):
KVM: PPC: Book3S HV: Add H_SET_MODE hcall handling
Mihai Caraman (8):
KVM: PPC: e500mc: Enhance tlb invalidation condition on vcpu schedule
KVM: PPC: e500: Fix default tlb for victim hint
KVM: PPC: e500: Emulate power management control SPR
KVM: PPC: e500mc: Revert "add load inst fixup"
KVM: PPC: Book3e: Add TLBSEL/TSIZE defines for MAS0/1
KVM: PPC: Book3s: Remove kvmppc_read_inst() function
KVM: PPC: Allow kvmppc_get_last_inst() to fail
KVM: PPC: Bookehv: Get vcpu's last instruction for emulation
Paul Mackerras (4):
KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handling
KVM: PPC: Book3S: Allow only implemented hcalls to be enabled or disabled
KVM: PPC: Book3S PR: Take SRCU read lock around RTAS kvm_read_guest() call
KVM: PPC: Book3S: Make kvmppc_ld return a more accurate error indication
Stewart Smith (2):
Split out struct kvmppc_vcore creation to separate function
Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8
Conflicts:
Documentation/virtual/kvm/api.txt
On book3e, KVM uses load external pid (lwepx) dedicated instruction to read
guest last instruction on the exit path. lwepx exceptions (DTLB_MISS, DSI
and LRAT), generated by loading a guest address, needs to be handled by KVM.
These exceptions are generated in a substituted guest translation context
(EPLC[EGS] = 1) from host context (MSR[GS] = 0).
Currently, KVM hooks only interrupts generated from guest context (MSR[GS] = 1),
doing minimal checks on the fast path to avoid host performance degradation.
lwepx exceptions originate from host state (MSR[GS] = 0) which implies
additional checks in DO_KVM macro (beside the current MSR[GS] = 1) by looking
at the Exception Syndrome Register (ESR[EPID]) and the External PID Load Context
Register (EPLC[EGS]). Doing this on each Data TLB miss exception is obvious
too intrusive for the host.
Read guest last instruction from kvmppc_load_last_inst() by searching for the
physical address and kmap it. This address the TODO for TLB eviction and
execute-but-not-read entries, and allow us to get rid of lwepx until we are
able to handle failures.
A simple stress benchmark shows a 1% sys performance degradation compared with
previous approach (lwepx without failure handling):
time for i in `seq 1 10000`; do /bin/echo > /dev/null; done
real 0m 8.85s
user 0m 4.34s
sys 0m 4.48s
vs
real 0m 8.84s
user 0m 4.36s
sys 0m 4.44s
A solution to use lwepx and to handle its exceptions in KVM would be to temporary
highjack the interrupt vector from host. This imposes additional synchronizations
for cores like FSL e6500 that shares host IVOR registers between hardware threads.
This optimized solution can be later developed on top of this patch.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
On book3e, guest last instruction is read on the exit path using load
external pid (lwepx) dedicated instruction. This load operation may fail
due to TLB eviction and execute-but-not-read entries.
This patch lay down the path for an alternative solution to read the guest
last instruction, by allowing kvmppc_get_lat_inst() function to fail.
Architecture specific implmentations of kvmppc_load_last_inst() may read
last guest instruction and instruct the emulation layer to re-execute the
guest in case of failure.
Make kvmppc_get_last_inst() definition common between architectures.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Tlb search operation used for victim hint relies on the default tlb set by the
host. When hardware tablewalk support is enabled in the host, the default tlb is
TLB1 which leads KVM to evict the bolted entry. Set and restore the default tlb
when searching for victim hint.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Reviewed-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
The patch 08c9a188d0
kvm: powerpc: use caching attributes as per linux pte
do not handle properly the error case, letting mmu_lock locked. The lock
will further generate a RCU stall from kvmppc_e500_emul_tlbwe() caller.
In case of an error go to out label.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
KVM uses same WIM tlb attributes as the corresponding qemu pte.
For this we now search the linux pte for the requested page and
get these cache caching/coherency attributes from pte.
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Reviewed-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
On booke, "struct tlbe_ref" contains host tlb mapping information
(pfn: for guest-pfn to pfn, flags: attribute associated with this mapping)
for a guest tlb entry. So when a guest creates a TLB entry then
"struct tlbe_ref" is set to point to valid "pfn" and set attributes in
"flags" field of the above said structure. When a guest TLB entry is
invalidated then flags field of corresponding "struct tlbe_ref" is
updated to point that this is no more valid, also we selectively clear
some other attribute bits, example: if E500_TLB_BITMAP was set then we clear
E500_TLB_BITMAP, if E500_TLB_TLB0 is set then we clear this.
Ideally we should clear complete "flags" as this entry is invalid and does not
have anything to re-used. The other part of the problem is that when we use
the same entry again then also we do not clear (started doing or-ing etc).
So far it was working because the selectively clearing mentioned above
actually clears "flags" what was set during TLB mapping. But the problem
starts coming when we add more attributes to this then we need to selectively
clear them and which is not needed.
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Reviewed-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Mark the guest page as accessed so that there is likely
less chances of this page getting swap-out.
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
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 TLBs 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
referencing a page.
This patch calls the mmu_notifier_retry() while mapping the guest
page to ensure we are not referencing a page when in range invalidation.
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.
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Acked-by: Alexander Graf <agraf@suse.de>
[Backported to 3.12 - Paolo]
Reviewed-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 523f0e5421 ("KVM: PPC: E500:
Explicitly mark shadow maps invalid") began using E500_TLB_VALID
for guest TLB1 entries, and skipping invalidations if it's not set.
However, when E500_TLB_VALID was set for such entries, it was on a
fake local ref, and so the invalidations never happen. gtlb_privs
is documented as being only for guest TLB0, though we already violate
that with E500_TLB_BITMAP.
Now that we have MMU notifiers, and thus don't need to actually
retain a reference to the mapped pages, get rid of tlb_refs, and
use gtlb_privs for E500_TLB_VALID in TLB1.
Since we can have more than one host TLB entry for a given tlbe_ref,
be careful not to clear existing flags that are relevant to other
host TLB entries when preparing a new host TLB entry.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
It's possible that we're using the same host TLB1 slot to map (a
presumably different portion of) the same guest TLB1 entry. Clear
the bit in the map before setting it, so that if the esels are the same
the bit will remain set.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Add one to esel values in h2g_tlb1_rmap, so that "no mapping" can be
distinguished from "esel 0". Note that we're not saved by the fact
that host esel 0 is reserved for non-KVM use, because KVM host esel
numbering is not the raw host numbering (see to_htlb1_esel).
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Host shadow TLB flushing is logic that the guest TLB code should have
no insight about. Declare the internal clear_tlb_refs and clear_tlb1_bitmap
functions static to the host TLB handling file.
Instead of these, we can use the already exported kvmppc_core_flush_tlb().
This gives us a common API across the board to say "please flush any
pending host shadow translation".
Signed-off-by: Alexander Graf <agraf@suse.de>
When a host mapping fault happens in a guest TLB1 entry today, we
map the translated guest entry into the host's TLB1.
This isn't particularly clever when the guest is mapped by normal 4k
pages, since these would be a lot better to put into TLB0 instead.
This patch adds the required logic to map 4k TLB1 shadow maps into
the host's TLB0.
Signed-off-by: Alexander Graf <agraf@suse.de>
This patch splits the file e500_tlb.c into e500_mmu.c (guest TLB handling)
and e500_mmu_host.c (host TLB handling).
The main benefit of this split is readability and maintainability. It's
just a lot harder to write dirty code :).
Signed-off-by: Alexander Graf <agraf@suse.de>
Aneesh Kumar K.V