> On May 3, 2022, at 2:52 PM, Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > On Thu, 24 Feb 2022 at 06:33, Steve French <smfrench@xxxxxxxxx> wrote: >> >> Currently creating tmpfiles on Linux can be problematic because the >> tmpfile is not created and opened at the same time (vfs_tmpfile calls >> into the fs, then later vfs_open is called to open the tmpfile). For >> some filesystems it would be more natural to create and open the >> tmpfile as one operation (because the action of creating the file on >> some filesystems returns an open handle, so closing it then reopening >> it would cause the tmpfile to be deleted). >> >> I would like to discuss whether the function do_tmpfile (which creates >> and then opens the tmpfile) could have an option for a filesystem to >> do this as one operation which would allow it to be more atomic and >> allow it to work on a wider variety of filesystems. > > A related thread: > > https://lore.kernel.org/all/20201109100343.3958378-3-chirantan@xxxxxxxxxxxx/#r > > There was no conclusion in the end. Not sure how hacky it would be to > store the open file in the inode... I just proposed adding a VFS API to make open/create atomic. See 8/8 in this thread: https://lore.kernel.org/linux-nfs/20220420192418.GB27805@xxxxxxxxxxxx/T/#m505a59ad4e4ed1413ffc055a088de3182fb50bb4 It adds a sibling API to dentry_open(). I didn't have O_TMPFILE in mind when I created this API. -- Chuck Lever
