> From: Seth Jennings [mailto:sjenning@xxxxxxxxxxxxxxxxxx] > Subject: Re: [PATCH] zsmalloc: use unsigned long instead of void * > > On 05/20/2012 09:23 PM, Minchan Kim wrote: > > > We should use unsigned long as handle instead of void * to avoid any > > confusion. Without this, users may just treat zs_malloc return value as > > a pointer and try to deference it. > > I wouldn't have agreed with you about the need for this change as people > should understand a void * to be the address of some data with unknown > structure. > > However, I recently discussed with Dan regarding his RAMster project > where he assumed that the void * would be an address, and as such, > 4-byte aligned. So he has masked two bits into the two LSBs of the > handle for RAMster, which doesn't work with zsmalloc since the handle is > not an address. > > So really we do need to convey as explicitly as possible to the user > that the handle is an _opaque_ value about which no assumption can be made. Someone once said: "Opaque is a computer science term and has no meaning in system software and computer engineering." ;-) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href