2008-03-24 18:01:33

by Aneesh Kumar K.V

Subject: [PATCH] arm: Export needed symbol for ZERO_PAGE usage in modules.

ext4 use ZERO_PAGE(0) to zero out blocks. We need to export
different symbols in different arch for the usage of ZERO_PAGE
in modules.

Signed-off-by: Aneesh Kumar K.V <[email protected]>
---
arch/arm/mm/mmu.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index d41a75e..2d6d682 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -35,6 +35,7 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
* zero-initialized data and COW.
*/
struct page *empty_zero_page;
+EXPORT_SYMBOL(empty_zero_page);

/*
* The pmd table for the upper-most set of pages.
--
1.5.5.rc0.16.g02b00.dirty

2008-03-24 19:06:27

by Andrew Morton

Subject: Re: [PATCH] arm: Export needed symbol for ZERO_PAGE usage in modules.

On Mon, 24 Mar 2008 23:31:29 +0530
"Aneesh Kumar K.V" <[email protected]> wrote:

> ext4 use ZERO_PAGE(0) to zero out blocks. We need to export
> different symbols in different arch for the usage of ZERO_PAGE
> in modules.
>
> Signed-off-by: Aneesh Kumar K.V <[email protected]>
> ---
> arch/arm/mm/mmu.c | 1 +
> 1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
> index d41a75e..2d6d682 100644
> --- a/arch/arm/mm/mmu.c
> +++ b/arch/arm/mm/mmu.c
> @@ -35,6 +35,7 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
> * zero-initialized data and COW.
> */
> struct page *empty_zero_page;
> +EXPORT_SYMBOL(empty_zero_page);
>
> /*

I wonder if it would be better to do this export in generic code.

Architectures which don't implement empty_zero_page:

alpha: seems to do something fancy
sparc64: need to rename mem_map_zero to empty_zero_page
v850: #define ZERO_PAGE(vaddr) ((void *)0x87654321) (wtf?)