On Tue, Dec 19, 2023 at 04:53:27PM +0000, John Garry wrote: > On 19/12/2023 15:17, Christoph Hellwig wrote: >> On Tue, Dec 19, 2023 at 12:41:37PM +0000, John Garry wrote: >>> How about something based on fcntl, like below? We will prob also require >>> some per-FS flag for enabling atomic writes without HW support. That flag >>> might be also useful for XFS for differentiating forcealign for atomic >>> writes with just forcealign. >> I would have just exposed it through a user visible flag instead of >> adding yet another ioctl/fcntl opcode and yet another method. >> > > Any specific type of flag? > > I would suggest a file attribute which we can set via chattr, but that is > still using an ioctl and would require a new inode flag; but at least there > is standard userspace support. I'd be fine with that, but we're kinda running out of flag there. That's why I suggested the FS_XFLAG_ instead, which basically works the same.