Eric Lee / linux-smarc-t335x-v3.2

23 Sep, 2009

1 commit

  • 562787a5c   anonfd: split interface into file creation and install ... Browse Code »

    Split the anonfd interface into a bare file pointer creation one, and a
    file pointer creation plus install one.

    There are cases, like the usage of eventfds inside other kernel
    interfaces, where the file pointer created by anonfd needs to be used
    inside the initialization of other structures.

    As it is right now, as soon as anon_inode_getfd() returns, the kenrle can
    race with userspace closing the newly installed file descriptor.

    This patch, while keeping the old anon_inode_getfd(), introduces a new
    anon_inode_getfile() (whose services are reused in anon_inode_getfd())
    that allows to split the file creation phase and the fd install one.

    Once all the kernel structures are initialized, the code can call the
    proper fd_install().

    Gregory manifested the need for something like this inside KVM.

    Signed-off-by: Davide Libenzi
    Cc: Alexander Viro
    Cc: James Morris
    Cc: Peter Zijlstra
    Cc: Gregory Haskins
    Acked-by: Serge Hallyn
    Acked-by: Roland Dreier
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Davide Libenzi
     

25 Jul, 2008

1 commit

  • 7d9dbca34   flag parameters: anon_inode_getfd extension ... Browse Code »

    This patch just extends the anon_inode_getfd interface to take an additional
    parameter with a flag value. The flag value is passed on to
    get_unused_fd_flags in anticipation for a use with the O_CLOEXEC flag.

    No actual semantic changes here, the changed callers all pass 0 for now.

    [akpm@linux-foundation.org: KVM fix]
    Signed-off-by: Ulrich Drepper
    Acked-by: Davide Libenzi
    Cc: Michael Kerrisk
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ulrich Drepper
     

02 May, 2008

1 commit

  • 2030a42ce   [PATCH] sanitize anon_inode_getfd() ... Browse Code »

    a) none of the callers even looks at inode or file returned by anon_inode_getfd()
    b) any caller that would try to look at those would be racy, since by the time
    it returns we might have raced with close() from another thread and that
    file would be pining for fjords.

    Signed-off-by: Al Viro

    Al Viro
     

11 May, 2007

1 commit

  • 5dc8bf813   signal/timer/event fds: anonymous inode source ... Browse Code »

    This patch add an anonymous inode source, to be used for files that need
    and inode only in order to create a file*. We do not care of having an
    inode for each file, and we do not even care of having different names in
    the associated dentries (dentry names will be same for classes of file*).
    This allow code reuse, and will be used by epoll, signalfd and timerfd
    (and whatever else there'll be).

    Signed-off-by: Davide Libenzi
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Davide Libenzi