On Mon, Jul 01, 2019 at 04:40:24PM +1000, Nicholas Piggin wrote:

walk_page_range() is going to be allowed to walk page tables other than
those of user space. For this it needs to know when it has reached a
'leaf' entry in the page tables. This information will be provided by the
p?d_large() functions/macros.

For arm64, we already have p?d_sect() macros which we can reuse for
p?d_large().

pud_sect() is defined as a dummy function when CONFIG_PGTABLE_LEVELS < 3
or CONFIG_ARM64_64K_PAGES is defined. However when the kernel is
configured this way then architecturally it isn't allowed to have a
large page that this level, and any code using these page walking macros
is implicitly relying on the page size/number of levels being the same as
the kernel. So it is safe to reuse this for p?d_large() as it is an
architectural restriction.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <redacted>
Signed-off-by: Steven Price <steven.price@arm.com>

Acked-by: Catalin Marinas <catalin.marinas@arm.com>

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