For those pte accessors, that operate on a different set of pte bits
between hash/radix, we add a generic variant that does a conditional
to hash linux or radix variant.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In this patch we add the radix Kconfig and conditional check.
radix_enabled() is written to always return 0 here. Once we have all
needed radix changes added, we will update this to an mmu_feature check.

We need to add this early so that we can get it all build in the early
stage.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This adds Power ISA 3.0 specific pte defines. We share most of the
details with hash Linux page table format. This patch indicates only
things where we differ.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Only code movement. No functionality change.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Now that the page table size is a variable, we can move these to
generic pgtable.h.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Radix and hash MMU models support different page table sizes. Make
the #defines a variable so that existing code can work with variable
sizes.

Slice related code is only used by hash, so use hash constants there. We
will replicate some of the boundary conditions with resepct to TASK_SIZE
using radix values too. Right now we do boundary condition check using
hash constants.

Swapper pgdir size is initialized in asm code. We select the max pgd
size to keep it simple. For now we select hash pgdir. When adding radix
we will switch that to radix pgdir which is 64K.

BUILD_BUG_ON check which is removed is already done in hugepage_init()
using MAYBE_BUILD_BUG_ON().
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

These pte functions will remain the same between radix and hash. Move
them to pgtable.h.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Now that we have moved book3s hash64 Linux pte bits to match Power ISA
3.0 radix pte bit positions, we move the matching pte bits to a common
header.

Only code movement in this patch. No functionality change.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

I am splitting this as a separate patch to get better review. If ok
we should merge this with previous patch.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This helps to make following hash only pte bits easier.

We have kept _PAGE_CHG_MASK, _HPAGE_CHG_MASK and _PAGE_PROT_BITS as it
is in this patch eventhough they use hash specific bits. Using them in
radix as it is should be ok, because with radix we expect those bit
positions to be zero.

Only renames in this patch, no change in functionality.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

PowerISA 3.0 adds a parition table indexed by LPID. Parition table
allows us to specify the MMU model that will be used for guest and host
translation.

This patch adds support with SLB based hash model (UPRT = 0). What is
required with this model is to support the new hash page table entry
format and also setup partition table such that we use hash table for
address translation.

We don't have segment table support yet.

In order to make sure we don't load KVM module on Power9 (since we don't
have kvm support yet) this patch also disables KVM on Power9.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Add structs and #defines related to the radix MMU partition table
format. We also add a ppc_md callback for updating a partition table
entry.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Start moving code that is generic between radix and hash to book3s64
specific headers from the book3s64 hash specific one.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The radix variant is going to require a flush_tlb_range(). With
flush_tlb_range() added, ptep_clear_flush_young() is the same as the
generic version. So drop the powerpc specific variant.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The radix variant is going to require a flush_pmd_tlb_range(). With
flush_pmd_tlb_range() added, pmdp_clear_flush_young() is the same as the
generic version. So drop the powerpc specific variant.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

PowerISA 3.0 introduces two pte bits with the below meaning for radix:
  00 -> Normal Memory
  01 -> Strong Access Order (SAO)
  10 -> Non idempotent I/O (Cache inhibited and guarded)
  11 -> Tolerant I/O (Cache inhibited)

We drop the existing WIMG bits in the Linux page table in favour of the
above constants. We loose _PAGE_WRITETHRU with this conversion. We only
use writethru via pgprot_cached_wthru() which is used by
fbdev/controlfb.c which is Apple control display and also PPC32.

With respect to _PAGE_COHERENCE, we have been marking hpte always
coherent for some time now. htab_convert_pte_flags() always added
HPTE_R_M.

NOTE: KVM changes need closer review.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

PS3 had used a PPP bit hack to implement a read only mapping in the
kernel area. Since we are bolting the ioremap area, it used the pte
flags _PAGE_PRESENT | _PAGE_USER to get a PPP value of 0x3 there by
resulting in a read only mapping. This means the area can be accessed by
user space, but kernel will never return such an address to user space.

But we can do better by implementing a read only kernel mapping using
PPP bits 0b110.

This also allows us to do read only kernel mapping for radix in later
patches.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

PTE_RPN_SHIFT is actually page size dependent. Even though PowerISA 3.0
expects only the lower 12 bits to be zero, we will always find the pages
to be PAGE_SHIFT aligned. In case of hash config, this also allows us to
use the additional 3 bits to track pte specific information. We need
to make sure we use these bits only for hash specific pte flags.

For both 4K and 64K config, pte now can hold 57 bits address.

Inorder to keep things simpler, drop PTE_RPN_SHIFT and PTE_RPN_SIZE and
specify the 57 bit detail explicitly.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

_PAGE_PRIVILEGED means the page can be accessed only by the kernel. This
is done to keep pte bits similar to PowerISA 3.0 Radix PTE format. User
pages are now marked by clearing _PAGE_PRIVILEGED bit.

Previously we allowed the kernel to have a privileged page in the lower
address range (USER_REGION). With this patch such access is denied.

We also prevent a kernel access to a non-privileged page in higher
address range (ie, REGION_ID != 0).

Both the above access scenarios should never happen.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

We have a common declaration in pte-common.h Add a book3s specific one
and switch to pte_user() in callchain.c. In a subsequent patch we will
switch _PAGE_USER to _PAGE_PRIVILEGED in the book3s version only.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In a subsequent patch we want to add a second definition of pte_user().
Before we do that, make the signature clear, ie. it takes a pte_t and
returns bool.

We move it up inside the existing #ifndef __ASSEMBLY__ block, but
otherwise it's a straight conversion.

Convert the call in settlbcam(), which passes an unsigned long, to pass
a pte_t.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This splits the _PAGE_RW bit into _PAGE_READ and _PAGE_WRITE. It also
removes the dependency on _PAGE_USER for implying read only. Few things
to note here is that, we have read implied with write and execute
permission. Hence we should always find _PAGE_READ set on hash pte
fault.

We still can't switch PROT_NONE to !(_PAGE_RWX). Auto numa depends on
marking a prot none pte _PAGE_WRITE. (For more details look at
b191f9b1 "mm: numa: preserve PTE write permissions across a NUMA
hinting fault")

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

We can avoid doing endian conversions by using pte_raw() in pxx_same().
The swap of the constant (_PAGE_HPTEFLAGS) should be done at compile
time by the compiler.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Traditionally Power server machines have used the Hashed Page Table MMU
mode. In this mode Linux manages its own tree of nested page tables,
aka. "the Linux page tables", which are not used by the hardware
directly, and software loads translations into the hash page table for
use by the hardware.

Power ISA 3.0 defines a new MMU mode, known as Radix Tree Translation,
where the hardware can directly operate on the Linux page tables.
However the hardware requires that the page tables be in big endian
format.

To accommodate this, switch the pgtable types to __be64 and add
appropriate endian conversions.

Because we will be supporting a single kernel binary that boots using
either radix or hash mode, we always store the Linux page tables big
endian, even in hash mode where they are not actually used by the
hardware.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Fix sparse errors, flesh out change log]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

We have five locations in 64-bit hash MMU code that do a cmpxchg() of a
PTE. Currently doing it inline OK, but in a future patch we will be
converting the PTEs to __be64 in some configs. In that case we will need
casts at every cmpxchg() site in order to keep sparse happy.

So move the logic into a helper, this is a reasonably nice cleanup on
its own.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

pmd_hugepage_update() is inside #ifdef CONFIG_TRANSPARENT_HUGEPAGE. THP
can only be enabled if PPC_BOOK3S_64=y && PPC_64K_PAGES=y, aka. hash64.

On hash64 we always define PTE_ATOMIC_UPDATES to 1, meaning the #ifdef
in pmd_hugepage_update() is unnecessary, so drop it.

That is also the only use of PTE_ATOMIC_UPDATES in any of the hash code,
meaning we no longer need to #define it at all in the hash headers.

Note it's still #defined and used in the nohash code.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Testing done by Paul Mackerras has shown that with a modern compiler
there is no negative effect on code generation from enabling
STRICT_MM_TYPECHECKS.

So remove the option, and always use the strict type definitions.
Acked-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The copy paste facility introduced in POWER9 provides an optimised
mechanism for a userspace application to copy a cacheline. This is
provided by a pair of instructions, copy and paste, while a third,
cp_abort (copy paste abort), provides a clean up of the state in case of
a failure.

The copy instruction will read a 128 byte cacheline and store it in an
internal buffer. The subsequent paste instruction will store this
internal buffer to memory and set a CR field if the paste succeeds.

Since the state of the copy paste buffer is internal (and not
architecturally visible), in the unlikely event of a context switch, the
state cannot be stored and the paste should therefore fail.

The cp_abort instruction exists to fail and clean up any such
interrupted copy paste sequence and is to be called by the kernel as
part of the context switch. Doing so prevents data from a preceding copy
in one process leaking into the paste of another.

This code enables use of the cp_abort instruction if a supported
processor is detected.

NOTE: this is for userspace only, not in kernel, and does not deal
with KVM guests.

Patch created with much assistance from Michael Neuling
<mikey@neuling.org>
Signed-off-by: NChris Smart <chris@distroguy.com>
Reviewed-by: NCyril Bur <cyrilbur@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In order to support live patching we need to maintain an alternate
stack of TOC & LR values. We use the base of the stack for this, and
store the "live patch stack pointer" in struct thread_info.

Unlike the other fields of thread_info, we can not statically initialise
that value, so it must be done at run time.

This patch just adds the code to support that, it is not enabled until
the next patch which actually adds live patch support.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Acked-by: NBalbir Singh <bsingharora@gmail.com>

Add the powerpc specific livepatch definitions. In particular we provide
a non-default implementation of klp_get_ftrace_location().

This is required because the location of the mcount call is not constant
when using -mprofile-kernel (which we always do for live patching).
Signed-off-by: NTorsten Duwe <duwe@suse.de>
Signed-off-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Signed-off-by: NPhilippe Bergheaud <felix@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This patch assigns numbers to OPAL_MSG macros of enum opal_msg_type
to prevent accidental insertion of any new value in between and thus
break OPAL API. This is also helpful while backporting mainline kernel
changes to distros which run downlevel kernel and thus don't have all
OPAL messages defined, avoiding unnecessary bugs due to enum values
order mismatch.
Signed-off-by: NVipin K Parashar <vipin@linux.vnet.ibm.com>
Acked-by: NStewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

If CONFIG_HIBERNATION and CONFIG_PPC_BOOK3S_64 are set, code in
arch/powerpc/kernel/swsusp_amd64.S which uses the tlbia macro is enabled.
tlbia in turn uses tlbie, an instruction which takes more than one
operand in newer versions of POWER.  As such, the kernel fails to build
due to the assembler complaining about missing operands.

This can be worked around by assembling the instruction as in POWER4.
This fixes the build breakage caused by enabling CONFIG_HIBERNATION.
Hibernation is currently only tested on G5 PowerMacs, which should be
unaffected by this change.  For other platforms it may now build,
whether or not it works is a different story.
Signed-off-by: NRussell Currey <ruscur@russell.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The used_vsr flag is set if process has used VSX registers, not Altivec
registers. But the comment says otherwise, correct the comment.
Signed-off-by: NSimon Guo <wei.guo.simon@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

GCC < 4.9 is unable to build this, saying:

  arch/powerpc/mm/8xx_mmu.c:139:2: error: memory input 1 is not directly addressable

Change the one-element array into a simple variable to avoid this.

Fixes: 1458dd95 ("powerpc/8xx: Handle CPU6 ERRATA directly in mtspr() macro")
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

flush/clean/invalidate _dcache_range() functions are all very
similar and are quite short. They are mainly used in __dma_sync()
perf_event locate them in the top 3 consumming functions during
heavy ethernet activity

They are good candidate for inlining, as __dma_sync() does
almost nothing but calling them
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>

clear_pages() is never used expect by clear_page, and PPC32 is the
only architecture (still) having this function. Neither PPC64 nor
any other architecture has it.

This patch removes clear_pages() and moves clear_page() function
inline (same as PPC64) as it only is a few isns
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>

This patch adds inline functions to use dcbz, dcbi, dcbf, dcbst
from C functions
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>

CPU6 ERRATA is now handled directly in mtspr(), so we can use the
standard set_dec() fonction in all cases.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>

MPC8xx has an ERRATA on the use of mtspr() for some registers
This patch includes the ERRATA handling directly into mtspr() macro
so that mtspr() users don't need to bother about that errata
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>