[PATCH v2 4/5] arm64: introduce pfn_valid_region()

From: Jia He
Date: Sat Mar 24 2018 - 08:26:04 EST


This is the preparation for further optimizing in early_pfn_valid
on arm64.

Signed-off-by: Jia He <jia.he@xxxxxxxxxxxxxxxx>
---
arch/arm64/include/asm/page.h | 3 ++-
arch/arm64/mm/init.c | 25 ++++++++++++++++++++++++-
2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/page.h b/arch/arm64/include/asm/page.h
index 60d02c8..da2cba3 100644
--- a/arch/arm64/include/asm/page.h
+++ b/arch/arm64/include/asm/page.h
@@ -38,7 +38,8 @@ extern void clear_page(void *to);
typedef struct page *pgtable_t;

#ifdef CONFIG_HAVE_ARCH_PFN_VALID
-extern int pfn_valid(unsigned long);
+extern int pfn_valid(unsigned long pfn);
+extern int pfn_valid_region(unsigned long pfn, int *last_idx);
#endif

#include <asm/memory.h>
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 00e7b90..9122102 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -290,7 +290,30 @@ int pfn_valid(unsigned long pfn)
return memblock_is_map_memory(pfn << PAGE_SHIFT);
}
EXPORT_SYMBOL(pfn_valid);
-#endif
+
+int pfn_valid_region(unsigned long pfn, int *last_idx)
+{
+ unsigned long start_pfn, end_pfn;
+ struct memblock_type *type = &memblock.memory;
+
+ if (*last_idx != -1) {
+ start_pfn = PFN_DOWN(type->regions[*last_idx].base);
+ end_pfn= PFN_DOWN(type->regions[*last_idx].base +
+ type->regions[*last_idx].size);
+
+ if (pfn >= start_pfn && end_pfn < end_pfn)
+ return !memblock_is_nomap(
+ &memblock.memory.regions[*last_idx]);
+ }
+
+ *last_idx = memblock_search_pfn_regions(pfn);
+ if (*last_idx == -1)
+ return false;
+
+ return !memblock_is_nomap(&memblock.memory.regions[*last_idx]);
+}
+EXPORT_SYMBOL(pfn_valid_region);
+#endif /*CONFIG_HAVE_ARCH_PFN_VALID*/

#ifndef CONFIG_SPARSEMEM
static void __init arm64_memory_present(void)
--
2.7.4