lkml.org 
[lkml]   [2020]   [Oct]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH RFC PKS/PMEM 33/58] fs/cramfs: Utilize new kmap_thread()
On Tue, Oct 13, 2020 at 09:01:49PM +0100, Al Viro wrote:
> 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...

I was thinking along those lines as well especially because of the direction
this patch set takes kmap().

Thanks for pointing these out to me. How about I lift them to a common header?
But if not highmem.h where?

Ira

\
 
 \ /
  Last update: 2020-10-13 22:50    [W:0.138 / U:1.144 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site