Xin LI wrote: > On 12/20/10 15:10, Alexander Best wrote: >> i'd really like to see > >> 1) write caching to be turned on and off for individual hdds >> (i.e. hw.ata.X.wc) and > > This is possible. We may need to split the logic out from ad_init() as > the disk number is not known at that point if I understood the code > correctly.
ad_init() receives newbus device as an argument, so it does have the disk number. >> 2) to be able to turn write chaching on and off on the fly. > > If I understand the code correctly, this is merely issuing a SETFEATURE > at runtime and *should* be possible. The problem is atacontrol(8) does > not offer a way to issue the command directly as camcontrol(8) do. > >> any thoughts on these two topics? is it technically possible? It is possible, but I would recommend you to focus on CAM-based ATA. As first step you can easily execute SETFEATURE command just from camcontrol tool. As second, it could be added to adastart()/adadone() to be executed on each device attach/reset, same as in ad_init(). -- Alexander Motin _______________________________________________ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
