talos-obmc-linux/include/linux/refcount.h, branch dev-4.13-fsi

locking/refcount: Remove the half-implemented refcount_sub() API

2017-07-02T09:24:36+00:00

CONFIG_REFCOUNT_FULL=y (correctly) does not provide a refcount_sub(), which should not be part of proper refcount design patterns. Remove the erroneous extern and the later !CONFIG_REFCOUNT_FULL accidental implementation. Signed-off-by: Kees Cook Cc: Elena Reshetova Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: 29dee3c03abc ("locking/refcounts: Out-of-line everything") Link: http://lkml.kernel.org/r/20170701180129.GA17405@beast Signed-off-by: Ingo Molnar

locking/refcount: Create unchecked atomic_t implementation

2017-06-28T16:54:46+00:00

Many subsystems will not use refcount_t unless there is a way to build the kernel so that there is no regression in speed compared to atomic_t. This adds CONFIG_REFCOUNT_FULL to enable the full refcount_t implementation which has the validation but is slightly slower. When not enabled, refcount_t uses the basic unchecked atomic_t routines, which results in no code changes compared to just using atomic_t directly. Signed-off-by: Kees Cook Acked-by: Greg Kroah-Hartman Cc: Alexey Dobriyan Cc: Andrew Morton Cc: Arnd Bergmann Cc: Christoph Hellwig Cc: David S. Miller Cc: David Windsor Cc: Davidlohr Bueso Cc: Elena Reshetova Cc: Eric Biggers Cc: Eric W. Biederman Cc: Hans Liljestrand Cc: James Bottomley Cc: Jann Horn Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Manfred Spraul Cc: Peter Zijlstra Cc: Rik van Riel Cc: Serge E. Hallyn Cc: Thomas Gleixner Cc: arozansk@redhat.com Cc: axboe@kernel.dk Cc: linux-arch Link: http://lkml.kernel.org/r/20170621200026.GA115679@beast Signed-off-by: Ingo Molnar

locking/refcount: Add refcount_t API kernel-doc comments

2017-03-13T06:41:08+00:00

Signed-off-by: David Windsor Acked-by: Peter Zijlstra Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Thomas Gleixner Cc: elena.reshetova@intel.com Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/1489160052-20293-1-git-send-email-dwindsor@gmail.com Signed-off-by: Ingo Molnar

locking/refcounts: Add missing kernel.h header to have UINT_MAX defined

2017-02-24T08:02:10+00:00

Fix header dependency. Suggested-by: Arnaldo Carvalho de Melo Signed-off-by: Elena Reshetova Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1487855374-21993-1-git-send-email-elena.reshetova@intel.com Signed-off-by: Ingo Molnar

locking/refcounts: Out-of-line everything

2017-02-24T08:02:10+00:00

Linus asked to please make this real C code. And since size then isn't an issue what so ever anymore, remove the debug knob and make all WARN()s unconditional. Suggested-by: Linus Torvalds Signed-off-by: Peter Zijlstra (Intel) Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: dwindsor@gmail.com Cc: elena.reshetova@intel.com Cc: gregkh@linuxfoundation.org Cc: ishkamiel@gmail.com Cc: keescook@chromium.org Signed-off-by: Ingo Molnar

refcount_t: Introduce a special purpose refcount type

2017-02-10T08:04:19+00:00

Provide refcount_t, an atomic_t like primitive built just for refcounting. It provides saturation semantics such that overflow becomes impossible and thereby 'spurious' use-after-free is avoided. Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Ingo Molnar