lkml.org 
[lkml]   [2003]   [May]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: Race between vmtruncate and mapped areas?
    From
    Date




    > On Thu, May 15, 2003 at 02:20:00AM -0700, Andrew Morton wrote:
    > > Andrea Arcangeli <andrea@suse.de> wrote:
    > > >
    > > > and it's still racy
    > >
    > > damn, and it just booted ;)
    > >
    > > I'm just a little bit concerned over the ever-expanding inode. Do you
    > > think the dual sequence numbers can be replaced by a single generation
    > > counter?
    >
    > yes, I wrote it as a single counter first, but was unreadable and it had
    > more branches, so I added the other sequence number to make it cleaner.
    > I don't mind another 4 bytes, that cacheline should be hot anyways.
    >
    > > I do think that we should push the revalidate operation over into the
    vm_ops.
    > > That'll require an extra arg to ->nopage, but it has a spare one anyway
    (!).
    >
    > not sure why you need a callback, the lowlevel if needed can serialize
    > using the same locking in the address space that vmtruncate uses. I
    > would wait a real case need before adding a callback.

    FYI, we verified that the revalidate callback could also do the same
    job that the proposed nopagedone callback does -- permitting filesystems
    that provide their on vm_operations_struct to avoid the race between
    page faults and invalidating a page from a mapped file.

    Thanx, Paul

    -
    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: 2005-03-22 13:35    [W:0.030 / U:0.232 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site