On 04/04/2011, at 8:43 PM, Thordur Bjornsson wrote: > On Mon, Apr 04, 2011 at 12:34:17PM +0200, Otto Moerbeek wrote: >> On Mon, Apr 04, 2011 at 09:22:41AM +0000, Thordur Bjornsson wrote: >> >>> Hi, >>> >>> 1) Swapping to svnds has issues (pagedaemon deadlocks) and has been >>> broken since forever. >>> 2) Swapping to vnds makes no sense, why add another layer when you >>> can just swap to a regular file instead ? >>> >>> so stop supporting swapping to vnds. If this turns out to be kosher >>> I have a diff tested that removes vnds in favour of svnds. >> >> I don't know if this is the right check, but the & is redundant to get >> the address of a function. > It's the easiest check. It's "hard" to map a dev_t to a device since > it is MD, so checking for that function is the "best" way I could > come up with. > > And "doh" on the '&'. I'll commit with out it.
block drivers look themselves up by comparing to their own functions, so there is a precedent for doing it this way. > > >> -Otto >> >>> >>> >>> OK ? >>> >>> >>> Index: uvm/uvm_swap.c >>> =================================================================== >>> RCS file: /home/thib/cvs/src/sys/uvm/uvm_swap.c,v >>> retrieving revision 1.100 >>> diff -u -p -r1.100 uvm_swap.c >>> --- uvm/uvm_swap.c 21 Dec 2010 20:14:44 -0000 1.100 >>> +++ uvm/uvm_swap.c 4 Apr 2011 09:14:59 -0000 >>> @@ -912,6 +912,10 @@ swap_on(struct proc *p, struct swapdev * >>> vp = sdp->swd_vp; >>> dev = sdp->swd_dev; >>> >>> + /* no swapping to vnds. */ >>> + if (bdevsw[major(dev)].d_strategy == &vndstrategy) >>> + return (EOPNOTSUPP); >>> + >>> /* >>> * open the swap file (mostly useful for block device files to >>> * let device driver know what is up).
