Commit Graph

3596 Commits

Author SHA1 Message Date
Gavin Shan 454593e54c drivers/pci/hotplug: Mask PDC interrupt if required
We're supporting surprise hotplug on PCI slots behind root port
or PCIe switch downstream ports, which don't claim the capability
in hardware register (offset: PCIe cap + PCI_EXP_SLTCAP). PEX8718
is one of the examples. For those PCI slots, the PDC (Presence
Detection Change) event isn't reliable and the underly (skiboot)
firmware has best judgement.

This masks the PDC event when skiboot requests by "ibm,slot-broken-pdc"
property in PCI slot's device-tree node.

Reported-by: Hank Chang <hankmax0000@gmail.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Willie Liauw <williel@supermicro.com.tw>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-15 20:02:43 +11:00
Aneesh Kumar K.V 438e69b52b powerpc/mm/radix: Skip ptesync in pte update helpers
We do them at the start of tlb flush, and we are sure a pte update will be
followed by a tlbflush. Hence we can skip the ptesync in pte update helpers.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-15 20:02:41 +11:00
Aneesh Kumar K.V f4894b80b1 powerpc/mm/radix: Use ptep_get_and_clear_full when clearing pte for full mm
This helps us to do some optimization for application exit case, where we can
skip the DD1 style pte update sequence.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-15 20:02:40 +11:00
Aneesh Kumar K.V ca94573b9c powerpc/mm/radix: Update pte update sequence for pte clear case
In the kernel we do follow the below sequence in different code paths.
pte = ptep_get_clear(ptep)
....
set_pte_at(ptep, pte)

We do that for mremap, autonuma protection update and softdirty clearing. This
implies our optimization to skip a tlb flush when clearing a pte update is
not valid, because for DD1 system that followup set_pte_at will be done witout
doing the required tlbflush. Fix that by always doing the dd1 style pte update
irrespective of new_pte value. In a later patch we will optimize the application
exit case.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-15 20:02:40 +11:00
Michael Ellerman 36b390fd62 powerpc/mm: Fix build break with BOOK3S_64=n and MEMORY_HOTPLUG=y
The recently merged HPT (Hash Page Table) resize support broke the build
when BOOK3S_64=n (ie. 32-bit or 64-bit Book3E) and MEMORY_HOTPLUG=y:

  arch/powerpc/mm/mem.o: In function `.arch_add_memory':
  (.text+0x4e4): undefined reference to `.resize_hpt_for_hotplug'

Fix it by adding a dummy version.

Fixes: 438cc81a41 ("powerpc/pseries: Automatically resize HPT for memory hot add/remove")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-15 19:58:39 +11:00
Michael Ellerman da0e7e6276 Merge branch 'topic/ppc-kvm' into next
Merge the topic branch we're sharing with the kvm-ppc tree.
2017-02-14 17:18:29 +11:00
Michael Ellerman aad71e3928 powerpc/mm: Fix build break with RADIX=y & HUGETLBFS=n
If we enable RADIX but disable HUGETLBFS, the build breaks with:

  arch/powerpc/mm/pgtable-radix.c:557:7: error: implicit declaration of function 'pmd_huge'
  arch/powerpc/mm/pgtable-radix.c:588:7: error: implicit declaration of function 'pud_huge'

Fix it by stubbing those functions when HUGETLBFS=n.

Fixes: 4b5d62ca17 ("powerpc/mm: add radix__remove_section_mapping()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-14 16:54:21 +11:00
Michael Ellerman 99ad503287 powerpc: Add a prototype for mcount() so it can be versioned
Currently we get a warning that _mcount() can't be versioned:

  WARNING: EXPORT symbol "_mcount" [vmlinux] version generation failed, symbol will not be versioned.

Add a prototype to asm-prototypes.h to fix it.

The prototype is not really correct, mcount() is not a normal function,
it has a special ABI. But for the purpose of versioning it doesn't
matter.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:28:06 +11:00
Anju T 51c9c08439 powerpc/kprobes: Implement Optprobes
Current infrastructure of kprobe uses the unconditional trap instruction
to probe a running kernel. Optprobe allows kprobe to replace the trap
with a branch instruction to a detour buffer. Detour buffer contains
instructions to create an in memory pt_regs. Detour buffer also has a
call to optimized_callback() which in turn call the pre_handler(). After
the execution of the pre-handler, a call is made for instruction
emulation. The NIP is determined in advanced through dummy instruction
emulation and a branch instruction is created to the NIP at the end of
the trampoline.

To address the limitation of branch instruction in POWER architecture,
detour buffer slot is allocated from a reserved area. For the time
being, 64KB is reserved in memory for this purpose.

Instructions which can be emulated using analyse_instr() are the
candidates for optimization. Before optimization ensure that the address
range between the detour buffer allocated and the instruction being
probed is within +/- 32MB.

Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:28:04 +11:00
Naveen N. Rao 30176466e3 powerpc/kprobes: Fixes for kprobe_lookup_name() on BE
Fix two issues with kprobes.h on BE which were exposed with the
optprobes work:
  - one, having to do with a missing include for linux/module.h for
    MODULE_NAME_LEN -- this didn't show up previously since the only
    users of kprobe_lookup_name were in kprobes.c, which included
    linux/module.h through other headers, and
  - two, with a missing const qualifier for a local variable which ends
    up referring a string literal. Again, this is unique to how
    kprobe_lookup_name is being invoked in optprobes.c

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:28:04 +11:00
Anju T ebfa50df43 powerpc: Add helper to check if offset is within relative branch range
To permit the use of relative branch instruction in powerpc, the target
address has to be relatively nearby, since the address is specified in an
immediate field (24 bit filed) in the instruction opcode itself. Here
nearby refers to 32MB on either side of the current instruction.

This patch verifies whether the target address is within +/- 32MB
range or not.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:28:03 +11:00
Naveen N. Rao c233f5979b powerpc/bpf: Introduce __PPC_SH64()
Introduce __PPC_SH64() as a 64-bit variant to encode shift field in some
of the shift and rotate instructions operating on double-words. Convert
some of the BPF instruction macros to use the same.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:28:03 +11:00
David Gibson 438cc81a41 powerpc/pseries: Automatically resize HPT for memory hot add/remove
We've now implemented code in the pseries platform to use the new PAPR
interface to allow resizing the hash page table (HPT) at runtime.

This patch uses that interface to automatically attempt to resize the HPT
when memory is hot added or removed.  This tries to always keep the HPT at
a reasonable size for our current memory size.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:28:02 +11:00
David Gibson 0de0fb09bb powerpc/pseries: Advertise HPT resizing support via CAS
The hypervisor needs to know a guest is capable of using the HPT resizing
PAPR extension in order to make full advantage of it for memory hotplug.

If the hypervisor knows the guest is HPT resize aware, it can size the
initial HPT based on the initial guest RAM size, relying on the guest to
resize the HPT when more memory is hot-added. Without this, the hypervisor
must size the HPT for the maximum possible guest RAM, which can lead to
a huge waste of space if the guest never actually expends to that maximum
size.

This patch advertises the guest's support for HPT resizing via the
ibm,client-architecture-support OF interface. We use bit 5 of byte 6 of
option vector 5 for this purpose, as defined in the PAPR ACR "HPT
resizing option".

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Reviewed-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:28:01 +11:00
David Gibson dbcf929c00 powerpc/pseries: Add support for hash table resizing
This adds support for using two hypercalls to change the size of the
main hash page table while running as a PAPR guest. For now these
hypercalls are only in experimental qemu versions.

The interface is two part: first H_RESIZE_HPT_PREPARE is used to
allocate and prepare the new hash table. This may be slow, but can be
done asynchronously. Then, H_RESIZE_HPT_COMMIT is used to switch to the
new hash table. This requires that no CPUs be concurrently updating the
HPT, and so must be run under stop_machine().

This also adds a debugfs file which can be used to manually control
HPT resizing or testing purposes.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Paul Mackerras <paulus@samba.org>
[mpe: Rename the debugfs file to "hpt_order"]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:27:55 +11:00
David Gibson 64b40ffbc8 powerpc/pseries: Add hypercall wrappers for hash page table resizing
This adds the hypercall numbers and wrapper functions for the hash page
table resizing hypercalls.

These hypercall numbers are defined in the PAPR ACR "HPT resizing
option".

It also adds a new firmware feature flag to track the presence of the
HPT resizing calls.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-09 21:45:48 +11:00
Benjamin Herrenschmidt ab9bad0ead powerpc/powernv: Remove separate entry for OPAL real mode calls
All entry points already read the MSR so they can easily do
the right thing.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-07 16:40:18 +11:00
Nicholas Piggin 2337d20728 powerpc/64: CONFIG_RELOCATABLE support for hmi interrupts
The branch from hmi_exception_early to hmi_exception_realmode must use
a "relocatable-style" branch, because it is branching from unrelocated
exception code to beyond __end_interrupts.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-07 16:39:44 +11:00
Aneesh Kumar K.V a5ecdad484 powerpc/mm: Add MMU_FTR_KERNEL_RO to possible feature mask
Without this we will always find the feature disabled.

Fixes: 984d7a1ec6 ("powerpc/mm: Fixup kernel read only mapping")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-07 16:29:55 +11:00
Nicholas Piggin 1a6822d194 powerpc/64s: Use (start, size) rather than (start, end) for exception handlers
start,size has the benefit of being easier to search for (start,end
usually gives you the preceeding vector from the one you want, as first
result).

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-07 07:26:57 +11:00
Nicholas Piggin 852e5da99d powerpc/64s: Tidy up after exception handler rework
Somewhere along the line, search/replace left some naming garbled,
and untidy alignment (aka. mpe stuffed it up). Might as well fix them
all up now while git blame history doesn't extend too far.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-07 07:26:57 +11:00
Benjamin Herrenschmidt 98a5f361b8 powerpc: Add new cache geometry aux vectors
This adds AUX vectors for the L1I,D, L2 and L3 cache levels
providing for each cache level the size of the cache in bytes
and the geometry (line size and number of ways).

We chose to not use the existing alpha/sh definition which
packs all the information in a single entry per cache level as
it is too restricted to represent some of the geometries used
on POWER.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-06 19:46:04 +11:00
Benjamin Herrenschmidt 65e01f386f powerpc/64: Add L2 and L3 cache shape info
Retrieved from device-tree when available

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-06 19:46:04 +11:00
Benjamin Herrenschmidt e2827fe5c1 powerpc/64: Clean up ppc64_caches using a struct per cache
We have two set of identical struct members for the I and D sides
and mostly identical bunches of code to parse the device-tree to
populate them. Instead make a ppc_cache_info structure with one
copy for I and one for D

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-06 19:46:04 +11:00
Benjamin Herrenschmidt 5d451a87e5 powerpc/64: Retrieve number of L1 cache sets from device-tree
It will be used to calculate the associativity

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-06 19:46:04 +11:00
Benjamin Herrenschmidt bd067f83b0 powerpc/64: Fix naming of cache block vs. cache line
In a number of places we called "cache line size" what is actually
the cache block size, which in the powerpc architecture, means the
effective size to use with cache management instructions (it can
be different from the actual cache line size).

We fix the naming across the board and properly retrieve both
pieces of information when available in the device-tree.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-06 19:46:04 +11:00
Benjamin Herrenschmidt 2a196e24b3 powerpc: Move ARCH_DLINFO out of uapi
It's an kernel private macro, it doesn't belong there

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-06 19:46:04 +11:00
John Allen e70d59700f powerpc/pseries: Introduce memory hotplug READD operation
Currently, memory must be hot removed and subsequently re-added in order
to dynamically update the affinity of LMBs specified by a PRRN event.
Earlier implementations of the PRRN event handler ran into issues in which
the hot remove would occur successfully, but a hotplug event would be
initiated from another source and grab the hotplug lock preventing the hot
add from occurring. To prevent this situation, this patch introduces the
notion of a hot "readd" action for memory which atomizes a hot remove and
a hot add into a single, serialized operation on the hotplug queue.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-02 16:57:39 +11:00
Daniel Axtens f2ca809059 powerpc/sparse: Constify the address pointer in __get_user_nosleep()
In __get_user_nosleep, we create an intermediate pointer for the
user address we're about to fetch. We currently don't tag this
pointer as const. Make it const, as we are simply dereferencing
it, and it's scope is limited to the __get_user_nosleep macro.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-02 16:35:21 +11:00
Daniel Axtens d466f6c5ca powerpc/sparse: Constify the address pointer in __get_user_nocheck()
In __get_user_nocheck, we create an intermediate pointer for the
user address we're about to fetch. We currently don't tag this
pointer as const. Make it const, as we are simply dereferencing
it, and it's scope is limited to the __get_user_nocheck macro.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-02 16:35:17 +11:00
Daniel Axtens f84ed59a61 powerpc/sparse: Constify the address pointer in __get_user_check()
In __get_user_check, we create an intermediate pointer for the
user address we're about to fetch. We currently don't tag this
pointer as const. Make it const, as we are simply dereferencing
it, and it's scope is limited to the __get_user_check macro.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-02 16:35:11 +11:00
Paul Mackerras 8cf4ecc0ca KVM: PPC: Book3S HV: Enable radix guest support
This adds a few last pieces of the support for radix guests:

* Implement the backends for the KVM_PPC_CONFIGURE_V3_MMU and
  KVM_PPC_GET_RMMU_INFO ioctls for radix guests

* On POWER9, allow secondary threads to be on/off-lined while guests
  are running.

* Set up LPCR and the partition table entry for radix guests.

* Don't allocate the rmap array in the kvm_memory_slot structure
  on radix.

* Don't try to initialize the HPT for radix guests, since they don't
  have an HPT.

* Take out the code that prevents the HV KVM module from
  initializing on radix hosts.

At this stage, we only support radix guests if the host is running
in radix mode, and only support HPT guests if the host is running in
HPT mode.  Thus a guest cannot switch from one mode to the other,
which enables some simplifications.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:52 +11:00
Paul Mackerras a29ebeaf55 KVM: PPC: Book3S HV: Invalidate TLB on radix guest vcpu movement
With radix, the guest can do TLB invalidations itself using the tlbie
(global) and tlbiel (local) TLB invalidation instructions.  Linux guests
use local TLB invalidations for translations that have only ever been
accessed on one vcpu.  However, that doesn't mean that the translations
have only been accessed on one physical cpu (pcpu) since vcpus can move
around from one pcpu to another.  Thus a tlbiel might leave behind stale
TLB entries on a pcpu where the vcpu previously ran, and if that task
then moves back to that previous pcpu, it could see those stale TLB
entries and thus access memory incorrectly.  The usual symptom of this
is random segfaults in userspace programs in the guest.

To cope with this, we detect when a vcpu is about to start executing on
a thread in a core that is a different core from the last time it
executed.  If that is the case, then we mark the core as needing a
TLB flush and then send an interrupt to any thread in the core that is
currently running a vcpu from the same guest.  This will get those vcpus
out of the guest, and the first one to re-enter the guest will do the
TLB flush.  The reason for interrupting the vcpus executing on the old
core is to cope with the following scenario:

	CPU 0			CPU 1			CPU 4
	(core 0)			(core 0)			(core 1)

	VCPU 0 runs task X      VCPU 1 runs
	core 0 TLB gets
	entries from task X
	VCPU 0 moves to CPU 4
							VCPU 0 runs task X
							Unmap pages of task X
							tlbiel

				(still VCPU 1)			task X moves to VCPU 1
				task X runs
				task X sees stale TLB
				entries

That is, as soon as the VCPU starts executing on the new core, it
could unmap and tlbiel some page table entries, and then the task
could migrate to one of the VCPUs running on the old core and
potentially see stale TLB entries.

Since the TLB is shared between all the threads in a core, we only
use the bit of kvm->arch.need_tlb_flush corresponding to the first
thread in the core.  To ensure that we don't have a window where we
can miss a flush, this moves the clearing of the bit from before the
actual flush to after it.  This way, two threads might both do the
flush, but we prevent the situation where one thread can enter the
guest before the flush is finished.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:51 +11:00
Paul Mackerras 8f7b79b837 KVM: PPC: Book3S HV: Implement dirty page logging for radix guests
This adds code to keep track of dirty pages when requested (that is,
when memslot->dirty_bitmap is non-NULL) for radix guests.  We use the
dirty bits in the PTEs in the second-level (partition-scoped) page
tables, together with a bitmap of pages that were dirty when their
PTE was invalidated (e.g., when the page was paged out).  This bitmap
is stored in the first half of the memslot->dirty_bitmap area, and
kvm_vm_ioctl_get_dirty_log_hv() now uses the second half for the
bitmap that gets returned to userspace.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:50 +11:00
Paul Mackerras 01756099e0 KVM: PPC: Book3S HV: MMU notifier callbacks for radix guests
This adapts our implementations of the MMU notifier callbacks
(unmap_hva, unmap_hva_range, age_hva, test_age_hva, set_spte_hva)
to call radix functions when the guest is using radix.  These
implementations are much simpler than for HPT guests because we
have only one PTE to deal with, so we don't need to traverse
rmap chains.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:49 +11:00
Paul Mackerras 5a319350a4 KVM: PPC: Book3S HV: Page table construction and page faults for radix guests
This adds the code to construct the second-level ("partition-scoped" in
architecturese) page tables for guests using the radix MMU.  Apart from
the PGD level, which is allocated when the guest is created, the rest
of the tree is all constructed in response to hypervisor page faults.

As well as hypervisor page faults for missing pages, we also get faults
for reference/change (RC) bits needing to be set, as well as various
other error conditions.  For now, we only set the R or C bit in the
guest page table if the same bit is set in the host PTE for the
backing page.

This code can take advantage of the guest being backed with either
transparent or ordinary 2MB huge pages, and insert 2MB page entries
into the guest page tables.  There is no support for 1GB huge pages
yet.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:49 +11:00
Paul Mackerras f4c51f841d KVM: PPC: Book3S HV: Modify guest entry/exit paths to handle radix guests
This adds code to  branch around the parts that radix guests don't
need - clearing and loading the SLB with the guest SLB contents,
saving the guest SLB contents on exit, and restoring the host SLB
contents.

Since the host is now using radix, we need to save and restore the
host value for the PID register.

On hypervisor data/instruction storage interrupts, we don't do the
guest HPT lookup on radix, but just save the guest physical address
for the fault (from the ASDR register) in the vcpu struct.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:48 +11:00
Paul Mackerras 9e04ba69be KVM: PPC: Book3S HV: Add basic infrastructure for radix guests
This adds a field in struct kvm_arch and an inline helper to
indicate whether a guest is a radix guest or not, plus a new file
to contain the radix MMU code, which currently contains just a
translate function which knows how to traverse the guest page
tables to translate an address.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:48 +11:00
Paul Mackerras 468808bd35 KVM: PPC: Book3S HV: Set process table for HPT guests on POWER9
This adds the implementation of the KVM_PPC_CONFIGURE_V3_MMU ioctl
for HPT guests on POWER9.  With this, we can return 1 for the
KVM_CAP_PPC_MMU_HASH_V3 capability.

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 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 bc3551257a powerpc/64: Allow for relocation-on interrupts from guest to host
With host and guest both using radix translation, it is feasible
for the host to take interrupts that come from the guest with
relocation on, and that is in fact what the POWER9 hardware will
do when LPCR[AIL] = 3.  All such interrupts use HSRR0/1 not SRR0/1
except for system call with LEV=1 (hcall).

Therefore this adds the KVM tests to the _HV variants of the
relocation-on interrupt handlers, and adds the KVM test to the
relocation-on system call entry point.

We also instantiate the relocation-on versions of the hypervisor
data storage and instruction interrupt handlers, since these can
occur with relocation on in radix guests.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:46 +11:00
Paul Mackerras dbcbfee0c8 powerpc/64: More definitions for POWER9
This adds definitions for bits in the DSISR register which are used
by POWER9 for various translation-related exception conditions, and
for some more bits in the partition table entry that will be needed
by KVM.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:45 +11:00
Paul Mackerras cc3d294013 powerpc/64: Enable use of radix MMU under hypervisor on POWER9
To use radix as a guest, we first need to tell the hypervisor via
the ibm,client-architecture call first that we support POWER9 and
architecture v3.00, and that we can do either radix or hash and
that we would like to choose later using an hcall (the
H_REGISTER_PROC_TBL hcall).

Then we need to check whether the hypervisor agreed to us using
radix.  We need to do this very early on in the kernel boot process
before any of the MMU initialization is done.  If the hypervisor
doesn't agree, we can't use radix and therefore clear the radix
MMU feature bit.

Later, when we have set up our process table, which points to the
radix tree for each process, we need to install that using the
H_REGISTER_PROC_TBL hcall.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:44 +11:00
Paul Mackerras 3f4ab2f83b powerpc/pseries: Fixes for the "ibm,architecture-vec-5" options
This fixes the byte index values for some of the option bits in
the "ibm,architectur-vec-5" property. The "platform facilities options"
bits are in byte 17 not byte 14, so the upper 8 bits of their
definitions need to be 0x11 not 0x0E. The "sub processor support" option
is in byte 21 not byte 15.

Note none of these options are actually looked up in
"ibm,architecture-vec-5" at this time, so there is no bug.

When checking whether option bits are set, we should check that
the offset of the byte being checked is less than the vector
length that we got from the hypervisor.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:44 +11:00
Nicholas Piggin a97a65d53d KVM: PPC: Book3S: 64-bit CONFIG_RELOCATABLE support for interrupts
64-bit Book3S exception handlers must find the dynamic kernel base
to add to the target address when branching beyond __end_interrupts,
in order to support kernel running at non-0 physical address.

Support this in KVM by branching with CTR, similarly to regular
interrupt handlers. The guest CTR saved in HSTATE_SCRATCH1 and
restored after the branch.

Without this, the host kernel hangs and crashes randomly when it is
running at a non-0 address and a KVM guest is started.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:07:39 +11:00
Reza Arbab 4b5d62ca17 powerpc/mm: add radix__remove_section_mapping()
Tear down and free the four-level page tables of physical mappings
during memory hotremove.

Borrow the basic structure of remove_pagetable() and friends from the
identically-named x86 functions. Reduce the frequency of tlb flushes and
page_table_lock spinlocks by only doing them in the outermost function.
There was some question as to whether the locking is needed at all.
Leave it for now, but we could consider dropping it.

Memory must be offline to be removed, thus not in use. So there
shouldn't be the sort of concurrent page walking activity here that
might prompt us to use RCU.

Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 13:54:19 +11:00
Reza Arbab 6cc27341b2 powerpc/mm: add radix__create_section_mapping()
Wire up memory hotplug page mapping for radix. Share the mapping
function already used by radix_init_pgtable().

Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 13:54:19 +11:00
Benjamin Herrenschmidt b3c711a9e1 powerpc: Add support for non-PCI ISA bridges
The POWER9 chip supports an LPC bus that isn't hanging
off a PCI bus, so let's add support for that, mapping it
to the reserved space at ISA_IO_BASE

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 13:54:17 +11:00
Benjamin Herrenschmidt 38e9d36bc1 powerpc: Move isa bridge definitions to separate include
We'll be adding non-PCI isa bridge support so let's not
have all the definition in pci-bridge.h

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 13:54:17 +11:00
Gautham R. Shenoy 09206b600c powernv: Pass PSSCR value and mask to power9_idle_stop
The power9_idle_stop method currently takes only the requested stop
level as a parameter and picks up the rest of the PSSCR bits from a
hand-coded macro. This is not a very flexible design, especially when
the firmware has the capability to communicate the psscr value and the
mask associated with a particular stop state via device tree.

This patch modifies the power9_idle_stop API to take as parameters the
PSSCR value and the PSSCR mask corresponding to the stop state that
needs to be set. These PSSCR value and mask are respectively obtained
by parsing the "ibm,cpu-idle-state-psscr" and
"ibm,cpu-idle-state-psscr-mask" fields from the device tree.

In addition to this, the patch adds support for handling stop states
for which ESL and EC bits in the PSSCR are zero. As per the
architecture, a wakeup from these stop states resumes execution from
the subsequent instruction as opposed to waking up at the System
Vector.

The older firmware sets only the Requested Level (RL) field in the
psscr and psscr-mask exposed in the device tree. For older firmware
where psscr-mask=0xf, this patch will set the default sane values that
the set for for remaining PSSCR fields (i.e PSLL, MTL, ESL, EC, and
TR). For the new firmware, the patch will validate that the invariants
required by the ISA for the psscr values are maintained by the
firmware.

This skiboot patch that exports fully populated PSSCR values and the
mask for all the stop states can be found here:
https://lists.ozlabs.org/pipermail/skiboot/2016-September/004869.html

[Optimize the number of instructions before entering STOP with
ESL=EC=0, validate the PSSCR values provided by the firimware
maintains the invariants required as per the ISA suggested by Balbir
Singh]

Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 08:32:13 +11:00