On Thu, Jun 30, 2016 at 04:12:48PM +0100, Dave Gordon wrote: > Two different sets of flag bits are stored in the 'flags' member of a > 'struct drm_i915_gem_exec_object2', and they're defined in two different > source files, increasing the risk of an accidental clash. > > Some flags in this field are supplied by the user; these are defined in > i915_drm.h, and they start from the LSB and work up. > > Other flags are defined in i915_gem_execbuffer, for internal use within > that file only; they start from the MSB and work down. > > So here we add a compile-time check that the two sets of flags do not > overlap, which would cause all sorts of confusion. > > Signed-off-by: Dave Gordon <[email protected]> > --- > drivers/gpu/drm/i915/i915_gem_execbuffer.c | 12 ++++++++---- > include/uapi/drm/i915_drm.h | 11 ++++++----- > 2 files changed, 14 insertions(+), 9 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c > b/drivers/gpu/drm/i915/i915_gem_execbuffer.c > index 7941f1f..608fdc4 100644 > --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c > +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c > @@ -34,10 +34,11 @@ > #include <linux/dma_remapping.h> > #include <linux/uaccess.h> > > -#define __EXEC_OBJECT_HAS_PIN (1<<31) > -#define __EXEC_OBJECT_HAS_FENCE (1<<30) > -#define __EXEC_OBJECT_NEEDS_MAP (1<<29) > -#define __EXEC_OBJECT_NEEDS_BIAS (1<<28) > +#define __EXEC_OBJECT_HAS_PIN (1<<31) > +#define __EXEC_OBJECT_HAS_FENCE (1<<30) > +#define __EXEC_OBJECT_NEEDS_MAP (1<<29) > +#define __EXEC_OBJECT_NEEDS_BIAS (1<<28) > +#define __EXEC_OBJECT_INTERNAL_FLAGS (0xf<<28) /* all of the above */
s/(0xf<<28)/(~(__EXEC_OBJECT_NEEDS_BIAS-1))/ if you feel like, with the comment retained. Either way: Reviewed-by: Daniel Vetter <[email protected]> > > #define BATCH_OFFSET_BIAS (256*1024) > > @@ -1007,6 +1008,9 @@ static bool only_mappable_for_reloc(unsigned int flags) > unsigned invalid_flags; > int i; > > + /* INTERNAL flags must not overlap with external ones */ > + BUILD_BUG_ON(__EXEC_OBJECT_INTERNAL_FLAGS & > ~__EXEC_OBJECT_UNKNOWN_FLAGS); > + > invalid_flags = __EXEC_OBJECT_UNKNOWN_FLAGS; > if (USES_FULL_PPGTT(dev)) > invalid_flags |= EXEC_OBJECT_NEEDS_GTT; > diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h > index c17d63d..079d274 100644 > --- a/include/uapi/drm/i915_drm.h > +++ b/include/uapi/drm/i915_drm.h > @@ -696,12 +696,13 @@ struct drm_i915_gem_exec_object2 { > */ > __u64 offset; > > -#define EXEC_OBJECT_NEEDS_FENCE (1<<0) > -#define EXEC_OBJECT_NEEDS_GTT (1<<1) > -#define EXEC_OBJECT_WRITE (1<<2) > +#define EXEC_OBJECT_NEEDS_FENCE (1<<0) > +#define EXEC_OBJECT_NEEDS_GTT (1<<1) > +#define EXEC_OBJECT_WRITE (1<<2) > #define EXEC_OBJECT_SUPPORTS_48B_ADDRESS (1<<3) > -#define EXEC_OBJECT_PINNED (1<<4) > -#define __EXEC_OBJECT_UNKNOWN_FLAGS -(EXEC_OBJECT_PINNED<<1) > +#define EXEC_OBJECT_PINNED (1<<4) > +/* All remaining bits are MBZ and RESERVED FOR FUTURE USE */ > +#define __EXEC_OBJECT_UNKNOWN_FLAGS (-(EXEC_OBJECT_PINNED<<1)) > __u64 flags; > > __u64 rsvd1; > -- > 1.9.1 > > _______________________________________________ > Intel-gfx mailing list > [email protected] > https://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
