lkml.org 
[lkml]   [2006]   [May]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: splice(SPLICE_F_MOVE) problems
On Wed, May 03 2006, Oleg Nesterov wrote:
> On 05/03, Jens Axboe wrote:
> >
> > On Wed, May 03 2006, Oleg Nesterov wrote:
> >
> > > However, user_page_pipe_buf_steal() returns unlocked page in
> > > PIPE_BUF_FLAG_GIFT case. So, if add_to_page_cache() fails,
> > > unlock_page() will trigger BUG().
> >
> > It does, it calls generic_pipe_buf_steal() which locks it.
>
> What I have in splice.c:
>
> static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe,
> struct pipe_buffer *buf)
> {
> if (!(buf->flags & PIPE_BUF_FLAG_GIFT))
> return 1;
>
> return 0;
> }
>
> (I don't use git, reading Linus's tree via http).

Ah ok, it got fixed yesterday:

static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
if (!(buf->flags & PIPE_BUF_FLAG_GIFT))
return 1;
return generic_pipe_buf_steal(pipe, buf);
}
> > > ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len);
> > > if (ret == AOP_TRUNCATED_PAGE) {
> > > page_cache_release(page);
> > > goto find_page;
> > >
> > > We also need to unlock(page) if it was stealed.
> >
> > Are you sure that's the right test? Don't you mean if ret !=
> > AOP_TRUNCATED_PAGE && ret?
> >
> > How about the attached?
>
> Ah, yes, you are right. Sorry for confusion.

Good, I already committed that variant of the fix :)

--
Jens Axboe

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-05-03 12:51    [W:0.066 / U:0.136 seconds]
©2003-2011 Jasper Spaans. Advertise on this site