30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

19 Feb, 2010

1 commit


13 Jul, 2009

1 commit

  • This makes generic netlink network namespace aware. No
    generic netlink families except for the controller family
    are made namespace aware, they need to be checked one by
    one and then set the family->netnsok member to true.

    A new function genlmsg_multicast_netns() is introduced to
    allow sending a multicast message in a given namespace,
    for example when it applies to an object that lives in
    that namespace, a new function genlmsg_multicast_allns()
    to send a message to all network namespaces (for objects
    that do not have an associated netns).

    The function genlmsg_multicast() is changed to multicast
    the message in just init_net, which is currently correct
    for all generic netlink families since they only work in
    init_net right now. Some will later want to work in all
    net namespaces because they do not care about the netns
    at all -- those will have to be converted to use one of
    the new functions genlmsg_multicast_allns() or
    genlmsg_multicast_netns() whenever they are made netns
    aware in some way.

    After this patch families can easily decide whether or
    not they should be available in all net namespaces. Many
    genl families us it for objects not related to networking
    and should therefore be available in all namespaces, but
    that will have to be done on a per family basis.

    Note that this doesn't touch on the checkpoint/restart
    problem where network namespaces could be used, genl
    families and multicast groups are numbered globally and
    I see no easy way of changing that, especially since it
    must be possible to multicast to all network namespaces
    for those families that do not care about netns.

    Signed-off-by: Johannes Berg
    Signed-off-by: David S. Miller

    Johannes Berg
     

22 May, 2009

1 commit


20 May, 2009

1 commit

  • nlmsg_new() adds the size of the netlink header to the value
    that has been passed as parameter. If NLMSG_GOODSIZE is selected,
    we request an allocation of one memory page plus the size of the
    header. Instead, NLMSG_DEFAULT_SIZE should be used since it
    already substracts the size of the Netlink header.

    I have the impression that the similar naming in both constant
    is error prone when using it with nlmsg_new(). This is already
    documented in include/net/netlink.h

    Signed-off-by: Pablo Neira Ayuso
    Signed-off-by: David S. Miller

    Pablo Neira Ayuso
     

08 Jul, 2008

1 commit

  • Fix an incorrect return value check of genlmsg_put() in irda_nl_get_mode().
    genlmsg_put() does not use ERR_PTR() to encode return values, it just
    returns NULL on error.

    Signed-off-by: Julius Volz
    Signed-off-by: Samuel Ortiz
    Signed-off-by: David S. Miller

    Julius Volz
     

06 Mar, 2008

1 commit


11 Oct, 2007

1 commit

  • This patch makes most of the generic device layer network
    namespace safe. This patch makes dev_base_head a
    network namespace variable, and then it picks up
    a few associated variables. The functions:
    dev_getbyhwaddr
    dev_getfirsthwbytype
    dev_get_by_flags
    dev_get_by_name
    __dev_get_by_name
    dev_get_by_index
    __dev_get_by_index
    dev_ioctl
    dev_ethtool
    dev_load
    wireless_process_ioctl

    were modified to take a network namespace argument, and
    deal with it.

    vlan_ioctl_set and brioctl_set were modified so their
    hooks will receive a network namespace argument.

    So basically anthing in the core of the network stack that was
    affected to by the change of dev_base was modified to handle
    multiple network namespaces. The rest of the network stack was
    simply modified to explicitly use &init_net the initial network
    namespace. This can be fixed when those components of the network
    stack are modified to handle multiple network namespaces.

    For now the ifindex generator is left global.

    Fundametally ifindex numbers are per namespace, or else
    we will have corner case problems with migration when
    we get that far.

    At the same time there are assumptions in the network stack
    that the ifindex of a network device won't change. Making
    the ifindex number global seems a good compromise until
    the network stack can cope with ifindex changes when
    you change namespaces, and the like.

    Signed-off-by: Eric W. Biederman
    Signed-off-by: David S. Miller

    Eric W. Biederman
     

22 Aug, 2007

1 commit


22 Jul, 2007

1 commit


11 Jul, 2007

1 commit