When we gain MMID support we'll be storing MMIDs as atomic64_t values
and accessing them via atomic64_* functions. This necessitates that we
don't use cpu_context() as the left hand side of an assignment, ie. as a
modifiable lvalue. In preparation for this introduce a new
set_cpu_context() function & replace all assignments with cpu_context()
on their left hand side with an equivalent call to set_cpu_context().
To enforce that cpu_context() should not be used for assignments, we
rewrite it as a static inline function.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Introduce a new check_mmu_context() function to check an mm's ASID
version & get a new one if it's outdated, and a
check_switch_mmu_context() function which additionally sets up the new
ASID & page directory. Simplify switch_mm() & various
get_new_mmu_context() callsites in MIPS KVM by making use of the new
functions, which will help reduce the amount of code that requires
modification to gain MMID support.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
get_new_mmu_context() accepts a cpu argument, but implicitly assumes
that this is always equal to smp_processor_id() by operating on the
local CPU's TLB & icache.
Remove the cpu argument and have get_new_mmu_context() call
smp_processor_id() instead.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
A first step in vcpu->requests encapsulation. Additionally, we now
use READ_ONCE() when accessing vcpu->requests, which ensures we
always load vcpu->requests when it's accessed. This is important as
other threads can change it any time. Also, READ_ONCE() documents
that vcpu->requests is used with other threads, likely requiring
memory barriers, which it does.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[ Documented the new use of READ_ONCE() and converted another check
in arch/mips/kvm/vz.c ]
Signed-off-by: Andrew Jones <drjones@redhat.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Octeon CPUs don't report the correct dcache line size in CP0_Config1.DL,
so encode the correct value for the guest CP0_Config1.DL based on
cpu_dcache_line_size().
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Daney <david.daney@cavium.com>
Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Abstract the MIPS KVM guest CP0 register access macros into inline
functions which are generated by macros. This allows them to be
generated differently for VZ, where they will usually need to access the
hardware guest CP0 context rather than the saved values in RAM.
Accessors for each individual register are generated using these macros:
- __BUILD_KVM_*_SW() for registers which are not present in the VZ
hardware guest context, so kvm_{read,write}_c0_guest_##name() will
access the saved value in RAM regardless of whether VZ is enabled.
- __BUILD_KVM_*_HW() for registers which are present in the VZ hardware
guest context, so kvm_{read,write}_c0_guest_##name() will access the
hardware register when VZ is enabled.
These build the underlying accessors using further macros:
- __BUILD_KVM_*_SAVED() builds e.g. kvm_{read,write}_sw_gc0_##name()
functions for accessing the saved versions of the registers in RAM.
This is used for implementing the common
kvm_{read,write}_c0_guest_##name() accessors with T&E where registers
are always stored in RAM, but are also available with VZ HW registers
to allow them to be accessed while saved.
- __BUILD_KVM_*_VZ() builds e.g. kvm_{read,write}_vz_gc0_##name()
functions for accessing the VZ hardware guest context registers
directly. This is used for implementing the common
kvm_{read,write}_c0_guest_##name() accessors with VZ.
- __BUILD_KVM_*_WRAP() builds wrappers with different names, which
allows the common kvm_{read,write}_c0_guest_##name() functions to be
implemented using the VZ accessors while still having the SAVED
accessors available too.
- __BUILD_KVM_SAVE_VZ() builds functions for saving and restoring VZ
hardware guest context register state to RAM, improving conciseness
of VZ context saving and restoring.
Similar macros exist for generating modifiers (set, clear, change),
either with a normal unlocked read/modify/write, or using atomic LL/SC
sequences.
These changes change the types of 32-bit registers to u32 instead of
unsigned long, which requires some changes to printk() functions in MIPS
KVM.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Add a callback for MIPS KVM implementations to handle the VZ guest
exit exception. Currently the trap & emulate implementation contains a
stub which reports an internal error, but the callback will be used
properly by the VZ implementation.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Add an implementation callback for the kvm_arch_hardware_enable() and
kvm_arch_hardware_disable() architecture functions, with simple stubs
for trap & emulate. This is in preparation for VZ which will make use of
them.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Add an implementation callback for checking presence of KVM extensions.
This allows implementation specific extensions to be provided without
ifdefs in mips.c.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Currently the software emulated timer is initialised to a frequency of
100MHz by kvm_mips_init_count(), but this isn't suitable for VZ where
the frequency of the guest timer matches that of the host.
Add a count_hz argument so the caller can specify the default frequency,
and move the call from kvm_arch_vcpu_create() to the implementation
specific vcpu_setup() callback, so that VZ can specify a different
frequency.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Emulate the HYPCALL instruction added in the VZ ASE and used by the MIPS
paravirtualised guest support that is already merged. The new hypcall.c
handles arguments and the return value. No actual hypercalls are yet
supported, but this still allows us to safely step over hypercalls and
set an error code in the return value for forward compatibility.
Non-zero HYPCALL codes are not handled.
We also document the hypercall ABI which asm/kvm_para.h uses.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Expose the CP0_IntCtl register through the KVM register access API,
which is a required register since MIPS32r2. It is currently read-only
since the VS field isn't implemented due to lack of Config3.VInt or
Config3.VEIC.
It is implemented in trap_emul.c so that a VZ implementation can allow
writes.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Expose the CP0_EntryLo0 and CP0_EntryLo1 registers through the KVM
register access API. This is fairly straightforward for trap & emulate
since we don't support the RI and XI bits. For the sake of future
proofing (particularly for VZ) it is explicitly specified that the API
always exposes the 64-bit version of these registers (i.e. with the RI
and XI bits in bit positions 63 and 62 respectively), and they are
implemented in trap_emul.c rather than mips.c to allow them to be
implemented differently for VZ.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Set the default VCPU state closer to the architectural reset state, with
PC pointing at the reset vector (uncached PA 0x1fc00000, which for KVM
T&E is VA 0x5fc00000), and with CP0_Status.BEV and CP0_Status.ERL to 1.
Although QEMU at least will overwrite this state, it makes sense to do
this now that CP0_EBase is properly implemented to check BEV, and now
that we support a sparse GPA layout potentially with a boot ROM at GPA
0x1fc00000.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
The CP0_EBase register is a standard feature of MIPS32r2, so we should
always have been implementing it properly. However the register value
was ignored and wasn't exposed to userland.
Fix the emulation of exceptions and interrupts to use the value stored
in guest CP0_EBase, and fix the masks so that the top 3 bits (rather
than the standard 2) are fixed, so that it is always in the guest KSeg0
segment.
Also add CP0_EBASE to the KVM one_reg interface so it can be accessed by
userland, also allowing the CPU number field to be written (which isn't
permitted by the guest).
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Access to various CP0 registers via the KVM register access API needs to
be implementation specific to allow restrictions to be made on changes,
for example when VZ guest registers aren't present, so move them all
into trap_emul.c in preparation for VZ.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Rewrite TLB modified exception handling to handle read only GPA memory
regions, instead of unconditionally passing the exception to the guest.
If the guest TLB is not the cause of the exception we call into the
normal TLB fault handling depending on the memory segment, which will
soon attempt to remap the physical page to be writable (handling dirty
page tracking or copy on write in the process).
Failing that we fall back to treating it as MMIO, due to a read only
memory region. Once the capability is enabled, this will allow read only
memory regions (such as the Malta boot flash as emulated by QEMU) to
have writes treated as MMIO, while still allowing reads to run
untrapped.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Treat unhandled accesses to guest KSeg0 as MMIO, rather than only host
KSeg0 addresses. This will allow read only memory regions (such as the
Malta boot flash as emulated by QEMU) to have writes (before reads)
treated as MMIO, and unallocated physical addresses to have all accesses
treated as MMIO.
The MMIO emulation uses the gva_to_gpa callback, so this is also updated
for trap & emulate to handle guest KSeg0 addresses.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Abstract the handling of bad guest loads and stores which may need to
trigger an MMIO, so that the same code can be used in a later patch for
guest KSeg0 addresses (TLB exception handling) as well as for host KSeg1
addresses (existing address error exception and TLB exception handling).
We now use kvm_mips_emulate_store() and kvm_mips_emulate_load() directly
rather than the more generic kvm_mips_emulate_inst(), as there is no
need to expose emulation of any other instructions.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
kvm_mips_map_page() will need to know whether the fault was due to a
read or a write in order to support dirty page tracking,
KVM_CAP_SYNC_MMU, and read only memory regions, so get that information
passed down to it via new bool write_fault arguments to various
functions.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Ignore userland writes to CP0_Config7 rather than reporting an error,
since we do allow reads of this register and it is claimed to exist in
the ioctl API.
This allows userland to blindly save and restore KVM registers without
having to special case certain registers as not being writable, for
example during live migration once dirty page logging is fixed.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Implement the kvm_arch_flush_shadow_all() and
kvm_arch_flush_shadow_memslot() KVM functions for MIPS to allow guest
physical mappings to be safely changed.
The general MIPS KVM code takes care of flushing of GPA page table
entries. kvm_arch_flush_shadow_all() flushes the whole GPA page table,
and is always called on the cleanup path so there is no need to acquire
the kvm->mmu_lock. kvm_arch_flush_shadow_memslot() flushes only the
range of mappings in the GPA page table corresponding to the slot being
flushed, and happens when memory regions are moved or deleted.
MIPS KVM implementation callbacks are added for handling the
implementation specific flushing of mappings derived from the GPA page
tables. These are implemented for trap_emul.c using
kvm_flush_remote_tlbs() which should now be functional, and will flush
the per-VCPU GVA page tables and ASIDS synchronously (before next
entering guest mode or directly accessing GVA space).
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Add helpers to allow for lockless direct access to the GVA space, by
changing the VCPU mode to READING_SHADOW_PAGE_TABLES for the duration of
the access. This allows asynchronous TLB flush requests in future
patches to safely trigger either a TLB flush before the direct GVA space
access, or a delay until the in-progress lockless direct access is
complete.
The kvm_trap_emul_gva_lockless_begin() and
kvm_trap_emul_gva_lockless_end() helpers take care of guarding the
direct GVA accesses, and kvm_trap_emul_gva_fault() tries to handle a
uaccess fault resulting from a flush having taken place.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
The stale ASID checks taking place on VCPU load can be reduced:
- Now that we check for a stale ASID on guest re-entry, there is no need
to do so when loading the VCPU outside of guest context, since it will
happen before entering the guest. Note that a lot of KVM VCPU ioctls
will cause the VCPU to be loaded but guest context won't be entered.
- There is no need to check for a stale kernel_mm ASID when the guest is
in user mode and vice versa. In fact doing so can potentially be
problematic since the user_mm ASID regeneration may trigger a new ASID
cycle, which would cause the kern_mm ASID to become stale after it has
been checked for staleness.
Therefore only check the ASID for the mm corresponding to the current
guest mode, and only if we're already in guest context. We drop some of
the related kvm_debug() calls here too.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Add handling of TLB invalidation requests before entering guest mode.
This will allow asynchonous invalidation of the VCPU mappings when
physical memory regions are altered. Should the CPU running the VCPU
already be in guest mode an IPI will be sent to trigger a guest exit.
The reload_asid path will be used in a future patch for when GVA is
about to be directly accessed by KVM.
In the process, the stale user ASID check in the re-entry path (for lazy
user GVA flushing) is generalised to check the ASID for the current
guest mode, in case a TLB invalidation request was handled. This has the
side effect of making the ASID checks on vcpu_load too conservative,
which will be addressed in a later patch.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
In order to make use of the CP0_BadInstr & CP0_BadInstrP registers we
need to be a bit more careful not to treat code fetch faults as MMIO,
lest we hit an UNPREDICTABLE register value when we try to emulate the
MMIO load instruction but there was no valid instruction word available
to the hardware.
Add a kvm_is_ifetch_fault() helper to try to figure out whether a load
fault was due to a code fetch, and prevent MMIO instruction emulation in
that case.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
MIPS KVM uses its own variation of get_new_mmu_context() which takes an
extra vcpu pointer (unused) and does exactly the same thing.
Switch to just using get_new_mmu_context() directly and drop KVM's
version of it as it doesn't really serve any purpose.
The nearby declarations of kvm_mips_alloc_new_mmu_context(),
kvm_mips_vcpu_load() and kvm_mips_vcpu_put() are also removed from
kvm_host.h, as no definitions or users exist.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Now that we have GVA page tables, use standard user accesses with page
faults disabled to read & modify guest instructions. This should be more
robust (than the rather dodgy method of accessing guest mapped segments
by just directly addressing them) and will also work with Enhanced
Virtual Addressing (EVA) host kernel configurations where dedicated
instructions are needed for accessing user mode memory.
For simplicity and speed we do this regardless of the guest segment the
address resides in, rather than handling guest KSeg0 specially with
kmap_atomic() as before.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Now that the commpage doesn't use wired TLB entries, the per-CPU
vm_init() callback is the only work done by kvm_mips_init_vm_percpu().
The trap & emulate implementation doesn't actually need to do anything
from vm_init(), and the future VZ implementation would be better served
by a kvm_arch_hardware_enable callback anyway.
Therefore drop the vm_init() callback entirely, allowing the
kvm_mips_init_vm_percpu() function to also be dropped, along with the
kvm_mips_instance atomic counter.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Implement invalidation of large ranges of virtual addresses from GVA
page tables in response to a guest ASID change (immediately for guest
kernel page table, lazily for guest user page table).
We iterate through a range of page tables invalidating entries and
freeing fully invalidated tables. To minimise overhead the exact ranges
invalidated depends on the flags argument to kvm_mips_flush_gva_pt(),
which also allows it to be used in future KVM_CAP_SYNC_MMU patches in
response to GPA changes, which unlike guest TLB mapping changes affects
guest KSeg0 mappings.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Activate the GVA page tables when in guest context. This will allow the
normal Linux TLB refill handler to fill from it when guest memory is
read, as well as preventing accidental reading from user memory.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Allocate GVA -> HPA page tables for guest kernel and guest user mode on
each VCPU, to allow for fast path TLB refill handling to be added later.
In the process kvm_arch_vcpu_init() needs updating to pass on any error
from the vcpu_init() callback.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Wire up a vcpu uninit implementation callback. This will be used for the
clean up of GVA->HPA page tables.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Set init_mm as the active_mm and update mm_cpumask(current->mm) to
reflect that it isn't active when in guest context. This prevents cache
management code from attempting cache flushes on host virtual addresses
while in guest context, for example due to a cache management IPIs or
later when writing of dynamically translated code hits copy on write.
We do this using helpers in static kernel code to avoid having to export
init_mm to modules.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
We only need the guest ASID loaded while in guest context, i.e. while
running guest code and while handling guest exits. We load the guest
ASID when entering the guest, however we restore the host ASID later
than necessary, when the VCPU state is saved i.e. vcpu_put() or slightly
earlier if preempted after returning to the host.
This mismatch is both unpleasant and causes redundant host ASID restores
in kvm_trap_emul_vcpu_put(). Lets explicitly restore the host ASID when
returning to the host, and don't bother restoring the host ASID on
context switch in unless we're already in guest context.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Add implementation callbacks for entering the guest (vcpu_run()) and
reentering the guest (vcpu_reenter()), allowing implementation specific
operations to be performed before entering the guest or after returning
to the host without cluttering kvm_arch_vcpu_ioctl_run().
This allows the T&E specific lazy user GVA flush to be moved into
trap_emul.c, along with disabling of the HTW. We also move
kvm_mips_deliver_interrupts() as VZ will need to restore the guest timer
state prior to delivering interrupts.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
The kvm_vcpu_arch structure contains both mm_structs for allocating MMU
contexts (primarily the ASID) but it also copies the resulting ASIDs
into guest_{user,kernel}_asid[] arrays which are referenced from uasm
generated code.
This duplication doesn't seem to serve any purpose, and it gets in the
way of generalising the ASID handling across guest kernel/user modes, so
lets just extract the ASID straight out of the mm_struct on demand, and
in fact there are convenient cpu_context() and cpu_asid() macros for
doing so.
To reduce the verbosity of this code we do also add kern_mm and user_mm
local variables where the kernel and user mm_structs are used.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
The MIPS KVM host and guest GVA ASIDs may need regenerating when
scheduling a process in guest context, which is done from the
kvm_arch_vcpu_load() / kvm_arch_vcpu_put() functions in mmu.c.
However this is a fairly implementation specific detail. VZ for example
may use GuestIDs instead of normal ASIDs to distinguish mappings
belonging to different guests, and even on VZ without GuestID the root
TLB will be used differently to trap & emulate.
Trap & emulate GVA ASIDs only relate to the user part of the full
address space, so can be left active during guest exit handling (guest
context) to allow guest instructions to be easily read and translated.
VZ root ASIDs however are for GPA mappings so can't be left active
during normal kernel code. They also aren't useful for accessing guest
virtual memory, and we should have CP0_BadInstr[P] registers available
to provide encodings of trapping guest instructions anyway.
Therefore move the ASID preemption handling into the implementation
callback.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Convert the get_regs() and set_regs() callbacks to vcpu_load() and
vcpu_put(), which provide a cpu argument and more closely match the
kvm_arch_vcpu_load() / kvm_arch_vcpu_put() that they are called by.
This is in preparation for moving ASID management into the
implementations.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Pull MIPS updates from Ralf Baechle:
"This is the main MIPS pull request for 4.9:
MIPS core arch code:
- traps: 64bit kernels should read CP0_EBase 64bit
- traps: Convert ebase to KSEG0
- c-r4k: Drop bc_wback_inv() from icache flush
- c-r4k: Split user/kernel flush_icache_range()
- cacheflush: Use __flush_icache_user_range()
- uprobes: Flush icache via kernel address
- KVM: Use __local_flush_icache_user_range()
- c-r4k: Fix flush_icache_range() for EVA
- Fix -mabi=64 build of vdso.lds
- VDSO: Drop duplicated -I*/-E* aflags
- tracing: move insn_has_delay_slot to a shared header
- tracing: disable uprobe/kprobe on compact branch instructions
- ptrace: Fix regs_return_value for kernel context
- Squash lines for simple wrapper functions
- Move identification of VP(E) into proc.c from smp-mt.c
- Add definitions of SYNC barrierstype values
- traps: Ensure full EBase is written
- tlb-r4k: If there are wired entries, don't use TLBINVF
- Sanitise coherentio semantics
- dma-default: Don't check hw_coherentio if device is non-coherent
- Support per-device DMA coherence
- Adjust MIPS64 CAC_BASE to reflect Config.K0
- Support generating Flattened Image Trees (.itb)
- generic: Introduce generic DT-based board support
- generic: Convert SEAD-3 to a generic board
- Enable hardened usercopy
- Don't specify STACKPROTECTOR in defconfigs
Octeon:
- Delete dead code and files across the platform.
- Change to use all memory into use by default.
- Rename upper case variables in setup code to lowercase.
- Delete legacy hack for broken bootloaders.
- Leave maintaining the link state to the actual ethernet/PHY drivers.
- Add DTS for D-Link DSR-500N.
- Fix PCI interrupt routing on D-Link DSR-500N.
Pistachio:
- Remove ANDROID_TIMED_OUTPUT from defconfig
TX39xx:
- Move GPIO setup from .mem_setup() to .arch_init()
- Convert to Common Clock Framework
TX49xx:
- Move GPIO setup from .mem_setup() to .arch_init()
- Convert to Common Clock Framework
txx9wdt:
- Add missing clock (un)prepare calls for CCF
BMIPS:
- Add PW, GPIO SDHCI and NAND device node names
- Support APPENDED_DTB
- Add missing bcm97435svmb to DT_NONE
- Rename bcm96358nb4ser to bcm6358-neufbox4-sercom
- Add DT examples for BCM63268, BCM3368 and BCM6362
- Add support for BCM3368 and BCM6362
PCI
- Reduce stack frame usage
- Use struct list_head lists
- Support for CONFIG_PCI_DOMAINS_GENERIC
- Make pcibios_set_cache_line_size an initcall
- Inline pcibios_assign_all_busses
- Split pci.c into pci.c & pci-legacy.c
- Introduce CONFIG_PCI_DRIVERS_LEGACY
- Support generic drivers
CPC
- Convert bare 'unsigned' to 'unsigned int'
- Avoid lock when MIPS CM >= 3 is present
GIC:
- Delete unused file smp-gic.c
mt7620:
- Delete unnecessary assignment for the field "owner" from PCI
BCM63xx:
- Let clk_disable() return immediately if clk is NULL
pm-cps:
- Change FSB workaround to CPU blacklist
- Update comments on barrier instructions
- Use MIPS standard lightweight ordering barrier
- Use MIPS standard completion barrier
- Remove selection of sync types
- Add MIPSr6 CPU support
- Support CM3 changes to Coherence Enable Register
SMP:
- Wrap call to mips_cpc_lock_other in mips_cm_lock_other
- Introduce mechanism for freeing and allocating IPIs
cpuidle:
- cpuidle-cps: Enable use with MIPSr6 CPUs.
SEAD3:
- Rewrite to use DT and generic kernel feature.
USB:
- host: ehci-sead3: Remove SEAD-3 EHCI code
FBDEV:
- cobalt_lcdfb: Drop SEAD3 support
dt-bindings:
- Document a binding for simple ASCII LCDs
auxdisplay:
- img-ascii-lcd: driver for simple ASCII LCD displays
irqchip i8259:
- i8259: Add domain before mapping parent irq
- i8259: Allow platforms to override poll function
- i8259: Remove unused i8259A_irq_pending
Malta:
- Rewrite to use DT
of/platform:
- Probe "isa" busses by default
CM:
- Print CM error reports upon bus errors
Module:
- Migrate exception table users off module.h and onto extable.h
- Make various drivers explicitly non-modular:
- Audit and remove any unnecessary uses of module.h
mailmap:
- Canonicalize to Qais' current email address.
Documentation:
- MIPS supports HAVE_REGS_AND_STACK_ACCESS_API
Loongson1C:
- Add CPU support for Loongson1C
- Add board support
- Add defconfig
- Add RTC support for Loongson1C board
All this except one Documentation fix has sat in linux-next and has
survived Imagination's automated build test system"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (127 commits)
Documentation: MIPS supports HAVE_REGS_AND_STACK_ACCESS_API
MIPS: ptrace: Fix regs_return_value for kernel context
MIPS: VDSO: Drop duplicated -I*/-E* aflags
MIPS: Fix -mabi=64 build of vdso.lds
MIPS: Enable hardened usercopy
MIPS: generic: Convert SEAD-3 to a generic board
MIPS: generic: Introduce generic DT-based board support
MIPS: Support generating Flattened Image Trees (.itb)
MIPS: Adjust MIPS64 CAC_BASE to reflect Config.K0
MIPS: Print CM error reports upon bus errors
MIPS: Support per-device DMA coherence
MIPS: dma-default: Don't check hw_coherentio if device is non-coherent
MIPS: Sanitise coherentio semantics
MIPS: PCI: Support generic drivers
MIPS: PCI: Introduce CONFIG_PCI_DRIVERS_LEGACY
MIPS: PCI: Split pci.c into pci.c & pci-legacy.c
MIPS: PCI: Inline pcibios_assign_all_busses
MIPS: PCI: Make pcibios_set_cache_line_size an initcall
MIPS: PCI: Support for CONFIG_PCI_DOMAINS_GENERIC
MIPS: PCI: Use struct list_head lists
...
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends. That changed
when we forked out support for the latter into the export.h file.
This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig. In the case of
kvm where it is modular, we can extend that to also include files
that are building basic support functionality but not related
to loading or registering the final module; such files also have
no need whatsoever for module.h
The advantage in removing such instances is that module.h itself
sources about 15 other headers; adding significantly to what we feed
cpp, and it can obscure what headers we are effectively using.
Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each instance for the
presence of either and replace as needed. In this case, we did
not need to add either to any files.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14036/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS Enhanced Virtual Addressing (EVA) allows the virtual memory
segments to be rearranged such that the KSeg0/KSeg1 segments are
accessible TLB mapped to user mode, which would trigger a TLB Miss
exception (due to lack of TLB mappings) instead of an Address Error
exception.
Update the TLB Miss handling similar to Address Error handling for guest
MMIO emulation.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Default the guest PRId register to represent a generic QEMU machine
instead of a 24kc on MIPSr6. 24kc isn't supported by r6 Linux kernels.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Convert MIPS KVM guest register state initialisation to use the standard
<asm/mipsregs.h> register field definitions for Config registers, and
drop the custom definitions in kvm_host.h which it was using before.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Initialise the guest's CP0_Config register with a few more bits of
information from the host. The BE bit should be set on big endian
machines, the VI bit should be set on machines with a virtually tagged
instruction cache, and the reported architecture revision should match
that of the host (since we won't support emulating pre-r6 instruction
encodings on r6 or vice versa).
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Allow up to 6 KVM guest KScratch registers to be enabled and accessed
via the KVM guest register API and from the guest itself (the fallback
reading and writing of commpage registers is sufficient for KScratch
registers to work as expected).
User mode can expose the registers by setting the appropriate bits of
the guest Config4.KScrExist field. KScratch registers that aren't usable
won't be writeable via the KVM Ioctl API.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Make the implementation of KVM_GET_REG_LIST more dynamic so that only
the subset of registers actually available can be exposed to user mode.
This is important for VZ where some of the guest register state may not
be possible to prevent the guest from accessing, therefore the user
process may need to be aware of the state even if it doesn't understand
what the state is for.
This also allows different MIPS KVM implementations to provide different
registers to one another, by way of new num_regs(vcpu) and
copy_reg_indices(vcpu, indices) callback functions, currently just
stubbed for trap & emulate.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The handle_tlb_ld/st_miss handlers are logically equivalent and
textually almost identical, so combine their implementations into a
single kvm_trap_emul_handle_tlb_miss().
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The CP0 Cause register is passed around in KVM quite a bit, often as an
unsigned long, even though it is always 32-bits long.
Resize it to u32 throughout MIPS KVM.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Convert the MIPS KVM C code to use standard kernel sized types (e.g.
u32) instead of inttypes.h style ones (e.g. uint32_t) or other types as
appropriate.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paul Burton