[PATCH -mm] relayfs: support larger relay buffer take 2

Pekka J Enberg penberg@cs.helsinki.fi
Wed Apr 16 19:52:00 GMT 2008


Hi Masami,

On Wed, 16 Apr 2008, Masami Hiramatsu wrote:
> +static struct page *relay_alloc_page_array(unsigned int n_pages)
> +{
> +	struct page *array;
> +	unsigned int pa_size = n_pages * sizeof(struct page *);
> +
> +	if (pa_size > PAGE_SIZE) {
> +		array = vmalloc(pa_size);
> +		if (array)
> +			memset(array, 0, pa_size);
> +	} else {
> +		array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL);
> +	}
> +	return array;
> +}

I think it's bit confusing to have relay_alloc_page_array() return a 
pointer to struct page as it's really allocating an _array_ of pointers to 
struct page. So why not just use void * here as the kernel memory 
allocators do?

> +static void relay_free_page_array(struct page *array)
> +{
> +	if (is_vmalloc_addr(array))
> +		vfree(array);
> +	else
> +		kfree(array);
> +}

Here as well.



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