ipc: introduce lockless pre_down ipcctl
authorDavidlohr Bueso <davidlohr.bueso@hp.com>
Wed, 1 May 2013 02:15:24 +0000 (19:15 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 1 May 2013 15:12:58 +0000 (08:12 -0700)
commit444d0f621b64716f7868dcbde448e0c66ece4e61
tree3947e0fe791c53c81d87a929af6d1b8e18a5c6aa
parent4d2bff5eb86e8d7b4a20934cccb93bdeebed3558
ipc: introduce lockless pre_down ipcctl

Various forms of ipc use ipcctl_pre_down() to retrieve an ipc object and
check permissions, mostly for IPC_RMID and IPC_SET commands.

Introduce ipcctl_pre_down_nolock(), a lockless version of this function.
The locking version is retained, yet modified to call the nolock version
without affecting its semantics, thus transparent to all ipc callers.

Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Chegu Vinod <chegu_vinod@hp.com>
Cc: Emmanuel Benisty <benisty.e@gmail.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ipc/util.c
ipc/util.h