Due to %p, (ptrval) is printed in lieu of the hash table address.

showing the hash table address isn't an operationnal need so just
don't print it.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Hash_end has never been used, drop it.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

For hash32, the zero shadow page gets mapped with PAGE_READONLY instead
of PAGE_KERNEL_RO, because the PP bits don't provide a RO kernel, so
PAGE_KERNEL_RO is equivalent to PAGE_KERNEL. By using PAGE_READONLY,
the page is RO for both kernel and user, but this is not a security issue
as it contains only zeroes.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

KASAN requires early activation of hash table, before memblock()
functions are available.

This patch implements an early hash_table statically defined in
__initdata.

During early boot, a single page table is used.

For hash32, when doing the final init, one page table is allocated
for each PGD entry because of the _PAGE_HASHPTE flag which can't be
common to several virt pages. This is done after memblock get
available but before switching to the final hash table, otherwise
there are issues with TLB flushing due to the shared entries.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

For KASAN, hash table handling will be activated early for
accessing to KASAN shadow areas.

In order to avoid any modification of the hash functions while
they are still used with the early hash table, the code patching
is moved out of MMU_init_hw() and put close to the big-bang switch
to the final hash table.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This patch adds KASAN support for PPC32. The following patch
will add an early activation of hash table for book3s. Until
then, a warning will be raised if trying to use KASAN on an
hash 6xx.

To support KASAN, this patch initialises that MMU mapings for
accessing to the KASAN shadow area defined in a previous patch.

An early mapping is set as soon as the kernel code has been
relocated at its definitive place.

Then the definitive mapping is set once paging is initialised.

For modules, the shadow area is allocated at module_alloc().
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

All files containing functions run before kasan_early_init() is called
must have KASAN instrumentation disabled.

For those file, branch profiling also have to be disabled otherwise
each if () generates a call to ftrace_likely_update().
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This patch prepares a shadow area for KASAN.

The shadow area will be at the top of the kernel virtual
memory space above the fixmap area and will occupy one
eighth of the total kernel virtual memory space.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When we add KASAN shadow area, KVIRT_TOP can't be anymore fixed
at 0xfe000000.

This patch uses FIXADDR_START to define KVIRT_TOP.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Since commit 400c47d8 ("powerpc32: memset: only use dcbz once cache is
enabled"), memset() can be used before activation of the cache,
so no need to use memset_io() for zeroing the BSS.
Acked-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In kernel/cputable.c, explicitly use memcpy() instead of *y = *x;
This will allow GCC to replace it with __memcpy() when KASAN is
selected.
Acked-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When KASAN is active, the string functions in lib/ are doing the
KASAN checks. This is too early for prom_init.

This patch implements dedicated string functions for prom_init,
which will be compiled in with KASAN disabled.

Size of prom_init before the patch:
   text	   data	    bss	    dec	    hex	filename
  12060	    488	   6960	  19508	   4c34	arch/powerpc/kernel/prom_init.o

Size of prom_init after the patch:
   text	   data	    bss	    dec	    hex	filename
  12460	    488	   6960	  19908	   4dc4	arch/powerpc/kernel/prom_init.o

This increases the size of prom_init a bit, but as prom_init is
in __init section, it is freed after boot anyway.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This patch makes CONFIG_CMDLINE defined at all time. It avoids
having to enclose related code inside #ifdef CONFIG_CMDLINE
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

CONFIG_KASAN implements wrappers for memcpy() memmove() and memset()
Those wrappers are doing the verification then call respectively
__memcpy() __memmove() and __memset(). The arches are therefore
expected to rename their optimised functions that way.

For files on which KASAN is inhibited, #defines are used to allow
them to directly call optimised versions of the functions without
going through the KASAN wrappers.

See commit 393f203f ("x86_64: kasan: add interceptors for
memset/memmove/memcpy functions") for details.

Other string / mem functions do not (yet) have kasan wrappers,
we therefore have to fallback to the generic versions when
KASAN is active, otherwise KASAN checks will be skipped.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
[mpe: Fixups to keep selftests working]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In preparation of KASAN, move early_init() into a separate
file in order to allow deactivation of KASAN for that function.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

pgd_alloc() and pgd_free() are identical on nohash 32 and 64.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

pmd_pgtable() is identical on the 4 subarches, refactor it.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

pgtable_free() and others are identical on nohash/32 and 64,
so move them into asm/nohash/pgalloc.h
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Use IS_ENABLED(CONFIG_BOOKE) to make single versions of
pmd_populate() and pmd_populate_kernel()
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

pgtable_cache[] is the same for the 4 subarches, lets make it common.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Functions pte_alloc_one(), pte_alloc_one_kernel(), pte_free(),
pte_free_kernel() are identical for the four subarches.

This patch moves their definition in a common place.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

pte_alloc_one_kernel() and pte_alloc_one() are simple calls to
pte_fragment_alloc(), so they are good candidates for inlining as
already done on PPC64.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In the same way as PPC64, implement early allocation functions and
avoid calling pte_alloc_kernel() before slab is available.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

early_alloc_pgtable() is only used during init.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Lets select PPC_MM_SLICES from the subarch config item instead of
doing it via defaults declaration in the PPC_MM_SLICES item itself.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Those files have no real added values, especially the 64 bit
which only includes the common book3e mmu.h which is also
included from 32 bits side.

So lets do the final inclusion directly from nohash/mmu.h
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

pgtable_t is now identical for all subarches, move it to the
top level asm/mmu.h
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Book3E 64 is the only subarch not using pte_fragment. In order
to allow refactorisation, this patch converts it to pte_fragment.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This has never been called (since Kernel has been in git at least),
drop it.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

__find_linux_pte() is full of if/else which is hard to
follow allthough the handling is pretty simple.

Previous patches left a { } block. This patch removes it.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

__find_linux_pte() is full of if/else which is hard to
follow allthough the handling is pretty simple.

Previous patch left { } blocks. This patch removes the first one
by shifting its content to the left.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

__find_linux_pte() is full of if/else which is hard to
follow allthough the handling is pretty simple.

This patch flattens the function by getting rid of as much if/else
as possible. In order to ease the review, this is done in three steps.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Only 3 subarches support huge pages. So when it is either 2 of them,
it is not the third one.

And mmu_has_feature() is known by all subarches so IS_ENABLED() can
be used instead of #ifdef
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Only book3s/64 may select default among several HPAGE_SHIFT at runtime.
8xx always defines 512K pages as default
FSL_BOOK3E always defines 4M pages as default

This patch limits HUGETLB_PAGE_SIZE_VARIABLE to book3s/64
moves the definitions in subarches files.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

No need to have this in asm/page.h, move it into asm/hugetlb.h
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Introduce a subarch specific helper check_and_get_huge_psize()
to check the huge page sizes and cleanup the ifdef mess in
add_huge_page_size()
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This patchs adds a subarch helper to populate hugepd.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Three subarches support hugepages:
  - fsl book3e
  - book3s/64
  - 8xx

This patch splits asm/hugetlb.h to reduce the #ifdef mess.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

gup_huge_pd() is the only user of gup_hugepte() and it is
located in the same file. This patch moves gup_huge_pd()
after gup_hugepte() and makes gup_hugepte() static.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The only function in hugetlbpage.c which doesn't depend on
CONFIG_HUGETLB_PAGE is gup_hugepte(), and this function is
only called from gup_huge_pd() which depends on
CONFIG_HUGETLB_PAGE so all the content of hugetlbpage.c
depends on CONFIG_HUGETLB_PAGE.

This patch modifies Makefile to only compile hugetlbpage.c
when CONFIG_HUGETLB_PAGE is set.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>