On Tue, Oct 13, 2020 at 08:36:43PM +0100, Matthew Wilcox wrote:
> static inline void copy_to_highpage(struct page *to, void *vfrom, unsigned int size)
> {
> char *vto = kmap_atomic(to);
>
> memcpy(vto, vfrom, size);
> kunmap_atomic(vto);
> }
>
> in linux/highmem.h ?
You mean, like
static void memcpy_from_page(char *to, struct page *page, size_t offset, size_t len)
{
char *from = kmap_atomic(page);
memcpy(to, from + offset, len);
kunmap_atomic(from);
}
static void memcpy_to_page(struct page *page, size_t offset, const char *from, size_t len)
{
char *to = kmap_atomic(page);
memcpy(to + offset, from, len);
kunmap_atomic(to);
}
static void memzero_page(struct page *page, size_t offset, size_t len)
{
char *addr = kmap_atomic(page);
memset(addr + offset, 0, len);
kunmap_atomic(addr);
}
in lib/iov_iter.c? FWIW, I don't like that "highpage" in the name and
highmem.h as location - these make perfect sense regardless of highmem;
they are normal memory operations with page + offset used instead of
a pointer...
