On Fri, 28 Oct 2011, Felipe Balbi wrote: > On Fri, Oct 28, 2011 at 03:22:16PM -0400, Alan Stern wrote: > > On Fri, 28 Oct 2011, Alan Stern wrote: > > > > > The important questions are: > > > > > > When are the right times to flush the page cache? > > > > > > Why should the MSC gadget have to worry about this in the > > > first place? That is, why doesn't the rest of the kernel > > > take care of this automatically? > > > > I just went back and looked at the SCSI spec. The description of START > > STOP UNIT says this: > > > > Targets that contain cache memory shall implicitly perform a > > SYNCHRONIZE CACHE command for the entire medium prior to > > executing the STOP UNIT command. > > > > That's pretty clear. Currently the do_start_stop() routine just calls > > fsg_lun_close(); it looks like we should put an fsg_lun_fsync_sub() > > call there too if the backing storage is not a regular file (and maybe > > even if it _is_ a regular file, if we want to obey the spec strictly). > > > > Then there won't be any need for fsg_lun_fsync_sub() in > > do_prevent_allow(). > > Makes sense to me. Care to send a patch to be queued for this -rc cycle? If Yuping or Barry would like to do it, that's fine with me. Otherwise I can send a patch. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
