arm64/mm: drop HAVE_ARCH_PFN_VALID

CONFIG_SPARSEMEM_VMEMMAP is now the only available memory model on arm64
platforms and free_unused_memmap() would just return without creating any
holes in the memmap mapping.  There is no need for any special handling in
pfn_valid() and HAVE_ARCH_PFN_VALID can just be dropped.  This also moves
the pfn upper bits sanity check into generic pfn_valid().

[rppt: rebased on v5.15-rc3]

Link: https://lkml.kernel.org/r/1621947349-25421-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Link: https://lore.kernel.org/r/20210930013039.11260-3-rppt@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

1 files changed, 0 insertions, 37 deletions

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 37a81754d9b6..e60c6eb813b7 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -160,43 +160,6 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
 	free_area_init(max_zone_pfns);
 }
 
-int pfn_valid(unsigned long pfn)
-{
-	phys_addr_t addr = PFN_PHYS(pfn);
-	struct mem_section *ms;
-
-	/*
-	 * Ensure the upper PAGE_SHIFT bits are clear in the
-	 * pfn. Else it might lead to false positives when
-	 * some of the upper bits are set, but the lower bits
-	 * match a valid pfn.
-	 */
-	if (PHYS_PFN(addr) != pfn)
-		return 0;
-
-	if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
-		return 0;
-
-	ms = __pfn_to_section(pfn);
-	if (!valid_section(ms))
-		return 0;
-
-	/*
-	 * ZONE_DEVICE memory does not have the memblock entries.
-	 * memblock_is_map_memory() check for ZONE_DEVICE based
-	 * addresses will always fail. Even the normal hotplugged
-	 * memory will never have MEMBLOCK_NOMAP flag set in their
-	 * memblock entries. Skip memblock search for all non early
-	 * memory sections covering all of hotplug memory including
-	 * both normal and ZONE_DEVICE based.
-	 */
-	if (!early_section(ms))
-		return pfn_section_valid(ms, pfn);
-
-	return memblock_is_memory(addr);
-}
-EXPORT_SYMBOL(pfn_valid);
-
 int pfn_is_map_memory(unsigned long pfn)
 {
 	phys_addr_t addr = PFN_PHYS(pfn);