On Mon, Feb 05, 2024 at 11:32:49AM -0500, Theodore Ts'o wrote: > On Mon, Feb 05, 2024 at 03:38:54PM +0530, Ojaswin Mujoo wrote: > > Hi folks, > > > > I'm trying to rework the ext4 atomic write patchset so we have similar > > semantics as discussed here [1], which would look something like: > > > > 1. we call FS_IOC_FSSETXATTR to enable atomic write on inode > > > > 2. In the setxattr path, we need to mark the inode with > > atomic_write_enabled. XFS does it via an on disk inode flag which is > > straightforward enough > > > > However, on ext4 we are almost out of 32 bits of inode flags and I don't > > think it's possible to add any flags2 field or something (iiuc, ondisk > > indoe doesn't have scope for expansion). > > We still have some unused flags. For example, > 0x01000000. 0x04000000. and 0x08000000 are still unused. We are > starting to get close to full, so we need to be a bit careful since it > is very much a limited resource. But we're not yet at the point where > we need to worry about trying to reuse flags like EXT4_EOFBLOCKS_FL. Hi Ted, Thats true, i don't even know how I missed that :) Sorry for the noise. Regards, ojaswin > > Cheers, > > - Ted
