[PATCH 05/28] sunrpc: don't call flush_dcache_page() with NULL page pointer

[J. Bruce Fields]

On Mon, Mar 31, 2008 at 10:31:18AM -0400, Kevin Coffman wrote:
> For architectures that implement flush_dcache_page(), the struct
> page pointer is not expected to be NULL.  In _copy_to_pages(),
> if the last bytes being copied are the exact last bytes of a
> complete page, then the final call to flush_dcache_page() has
> a null pointer.  Skip the call in that case.

A fix for this should actually go upstream now, right?

> 
> Signed-off-by: Kevin Coffman <kwc at citi.umich.edu>
> ---
> 
>  net/sunrpc/xdr.c |    3 ++-
>  1 files changed, 2 insertions(+), 1 deletions(-)
> 
> diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
> index de2c986..26991c6 100644
> --- a/net/sunrpc/xdr.c
> +++ b/net/sunrpc/xdr.c
> @@ -262,7 +262,8 @@ _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len)
>  		p += copy;
>  
>  	} while ((len -= copy) != 0);
> -	flush_dcache_page(*pgto);
> +	if (*pgto != NULL)
> +		flush_dcache_page(*pgto);
>  }

Can you necessarily count on the next entry in the page array being NULL?
Maybe better would be:

	if (pgbase != 0)
		flush_dcache_page(*pgto);

--b.

>  
>  /*
>