and I missed the following case. in some embedded systems, clean-up for shutdown should be fast. during this clean-up, freeze file system to guarantee integrity. umount with MNT_DETACH is not suitable because of not killing tasks. On Mon, May 29, 2017 at 10:18:34AM +0900, Hyunchul Lee wrote: > Hi, Richard. > > On Fri, May 26, 2017 at 11:52:42AM +0200, Richard Weinberger wrote: > > Hyunchul, > > > > Am 26.05.2017 um 01:30 schrieb Hyunchul Lee: > > > From: Hyunchul Lee <cheol.lee@xxxxxxx> > > > > > > for un/freeze support, implement freeze_super and un/freeze_fs > > > of super_operations. > > > ubifs_freeze_super just calls freeze_super. because freeze_super always > > > succeeds if file system is read-only, UBIFS errors should be checked. > > > if there are errors, UBIFS is switched to read-only mode. > > > ubifs_freeze_fs runs commit if TNC/LPT isn't clean. though all writes > > > are blocked and sync_fs is called before, if commit alreay was started > > > before writes are blocked, TNC/LPT might have dirty COW nodes. > > > > you explain how you implement that feature, but not why. > > What is the use-case? > > I always thought this interface is only being used by LVM. > > Sorry, I forgot this. I implement this to make a backup of some files, and > support fsfreeze utility and SysRq's freeze/thaw commmand. > > > > > Thanks, > > //richard > > > > ______________________________________________________ > > Linux MTD discussion mailing list > > http://lists.infradead.org/mailman/listinfo/linux-mtd/ > > -- > > Thanks, > Hyunchul > > ______________________________________________________ > Linux MTD discussion mailing list > http://lists.infradead.org/mailman/listinfo/linux-mtd/ -- Thanks, Hyunchul
