On 3/6/20 2:19 AM, qiwuchen55@xxxxxxxxx wrote:
> From: chenqiwu <chenqiwu@xxxxxxxxxx>
>
> Use wrapped macros instead of open-coding for better code
> readability.
>
> Signed-off-by: chenqiwu <chenqiwu@xxxxxxxxxx>
This breaks my x86 (64-bit) build:
mm/sparse.c: In function ‘check_usemap_section_nr’:
mm/sparse.c:389:33: error: implicit declaration of function ‘virt_to_pfn’; did you mean ‘virt_to_phys’? [-Werror=implicit-function-declaration]
389 | usemap_snr = pfn_to_section_nr(virt_to_pfn(usage));
| ^~~~~~~~~~~
| virt_to_phys
...and I think the reason is that the arch/x86/include/asm/page.h does not
have virt_to_pfn(). For that reason, I'm concerned that the following fix,
which fixes up x86, may not completely correct for the patch.
Here's a compile-tested (only, and only on x86 64-bit) fix:
diff --git a/arch/x86/include/asm/page.h b/arch/x86/include/asm/page.h
index 7555b48803a8..982bc76bf13c 100644
--- a/arch/x86/include/asm/page.h
+++ b/arch/x86/include/asm/page.h
@@ -62,6 +62,9 @@ static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
#define __boot_va(x) __va(x)
#define __boot_pa(x) __pa(x)
+#define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
+#define pfn_to_virt(pfn) __va((pfn) << PAGE_SHIFT)
+
/*
* virt_to_page(kaddr) returns a valid pointer if and only if
* virt_addr_valid(kaddr) returns true.
thanks,
--
John Hubbard
NVIDIA
> ---
> mm/sparse.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/mm/sparse.c b/mm/sparse.c
> index 42c18a3..9b14164 100644
> --- a/mm/sparse.c
> +++ b/mm/sparse.c
> @@ -385,8 +385,8 @@ static void __init check_usemap_section_nr(int nid,
> old_pgdat_snr = NR_MEM_SECTIONS;
> }
>
> - usemap_snr = pfn_to_section_nr(__pa(usage) >> PAGE_SHIFT);
> - pgdat_snr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
> + usemap_snr = pfn_to_section_nr(virt_to_pfn(usage));
> + pgdat_snr = pfn_to_section_nr(virt_to_pfn(pgdat));
> if (usemap_snr == pgdat_snr)
> return;
>
> @@ -677,7 +677,7 @@ struct page * __meminit populate_section_memmap(unsigned long pfn,
>
> return NULL;
> got_map_page:
> - ret = (struct page *)pfn_to_kaddr(page_to_pfn(page));
> + ret = (struct page *)page_to_virt(page);
> got_map_ptr:
>
> return ret;
>
