On Mon, Aug 07, 2017 at 10:20:58PM +0200, Arnd Bergmann wrote: > On Mon, Aug 7, 2017 at 6:45 PM, Darrick J. Wong <darrick.wong@xxxxxxxxxx> wrote: > > On Mon, Aug 07, 2017 at 06:01:43PM +0200, Arnd Bergmann wrote: > >> On Mon, Aug 7, 2017 at 5:54 PM, Darrick J. Wong <darrick.wong@xxxxxxxxxx> wrote: > >> > On Sun, Aug 06, 2017 at 06:44:24PM +0200, Mikko Rapeli wrote: > >> > >> Either way works, but including a system header from a kernel header > >> requires an additional "#ifndef __KERNEL__" check, so I think Miko's > >> variant is a little nicer. > >> > >> Generally speaking, you also want to avoid including system headers > >> indirectly from kernel headers, as POSIX requires that including one > >> system header should not indirectly make symbols from other system > >> headers visible. I think this is not a problem here though, as no system > >> header should include linux/fsmap.h. > > > > Sorry, I guess I was a little unclear about what I was asking -- I was > > wondering why can't the userspace program include sys/types.h prior to > > linux/fsmap.h? I wasn't proposing including C library headers in kernel > > headers. > > > > I think the patch author is pushing towards kernel headers never relying > > on /anything/ in the system headers. > > Right, and I think that is a good thing to have, because it allows us to > do better compile-time testing of the exported kernel headers. > > > For data structures being > > exchanged with the kernel I agree, but the fsmap_sizeof result is never > > passed to or received from the kernel; it exists purely for malloc > > convenience. > > Would you prefer making fsmap_sizeof a macro? That would also > make it possible to do static checking on the header without having > to resort to odd types. Ick, no macros, please. :) How about just change it to unsigned long long and call it a day? --D > > Arnd > -- > To unsubscribe from this list: send the line "unsubscribe linux-api" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
