lkml.org 
[lkml]   [2007]   [May]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 3/3] AFS: Implement basic file write support
David Howells wrote:
> Nick Piggin <nickpiggin@yahoo.com.au> wrote:
>
>
>>Why do you call SetPageUptodate when the page is not up to date?
>>That leaks uninitialised data, AFAIKS.
>
>
> It only seems that way. If afs_prepare_write() is called, but doesn't return
> an error, then afs_commit_write() will be called, and it seems that the copy
> in of the data will be guaranteed not to fail by the caller.

Not only does it seem that way, it is that way :) PG_uptodate is being set
when the page is not uptodate, isn't it?


> Furthermore, afs_prepare_page() will have filled in the missing bits.
>
> And whilst all that is going on, the page lock will be help by the caller, so
> that no-one else can access the partially complete page.

When a page is uptodate in pagecache, the generic read and nopage functions
do not take the page lock. So how are you excluding those?

--
SUSE Labs, Novell Inc.
-
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: 2007-05-11 08:17    [W:0.069 / U:0.184 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site