On Thu, Aug 26, 2010 at 07:14:36PM -0600, Matthew Wilcox wrote: > On Thu, Aug 26, 2010 at 04:03:18PM -0400, Valerie Aurora wrote: > > + /* Fail if any non-propagation flags are set */ > > + if (type & ~(MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE)) > > + return 0; > > + /* Only one propagation flag should be set */ > > + if (((type & (MS_SHARED)) && (type & ~MS_SHARED)) || > > + ((type & (MS_PRIVATE)) && (type & ~MS_PRIVATE)) || > > + ((type & (MS_SLAVE)) && (type & ~MS_SLAVE)) || > > + ((type & (MS_UNBINDABLE)) && (type & ~MS_UNBINDABLE))) > > + return 0; > > Hrm. I think we can do this a bit more pithily. > > /* Only one propagation flag should be set, and no others */ > if (hweight32(type) != 1 && > (type & ~(MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE)) > return 0; > > Too clever? I was hoping someone would go find the best bitop for me, thanks. :) hweight32() is an awkward name but the comment makes it clear. I'm happy with either. Thanks for the help, -VAL -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
