On Tue, Jun 28, 2022 at 03:57:14PM +0000, Wengang Wang wrote: > Hi Darrick, > > How about the V2? > > thanks, > wengang > > > On Jun 24, 2022, at 12:10 PM, Wengang Wang <wen.gang.wang@xxxxxxxxxx> wrote: > > > > During a reflink operation, the IOLOCK and MMAPLOCK of the source file > > are held in exclusive mode for the duration. This prevents reads on the > > source file, which could be a very long time if the source file has > > millions of extents. > > > > As the source of copy, besides some necessary modification (say dirty page > > flushing), it plays readonly role. Locking source file exclusively through > > out the full reflink copy is unreasonable. > > > > This patch downgrades exclusive locks on source file to shared modes after > > page cache flushing and before cloning the extents. To avoid source file > > change after lock downgradation, direct write paths take IOLOCK_EXCL on > > seeing reflink copy happening to the files. > > > > Signed-off-by: Wengang Wang <wen.gang.wang@xxxxxxxxxx> > > --- > > V2 changes: > > Commit message > > Make direct write paths take IOLOCK_EXCL when reflink copy is happening > > Tiny changes Version 2 never made it to the list. Please resend. -Dave. -- Dave Chinner david@xxxxxxxxxxxxx
