On Mon, Sep 18, 2023 at 12:59:15PM -0700, Linus Torvalds wrote: > On Mon, 18 Sept 2023 at 12:32, Jiri Kosina <jikos@xxxxxxxxxx> wrote: > > > > I am afraid this is not reflecting reality. > > > > I am pretty sure that "give me that document on a USB stick, and I'll take > > a look" leads to using things like libreoffice (or any other editor liked > > by general public) to open the file directly on the FAT USB stick. And > > that's pretty much guaranteed to use mmap(). > > Ugh. I would have hoped that anybody will fall back to read/write - > because we definitely have filesystems that don't support mmap. Fortunately, I most of the "simple" file systems appear to support mmap, via generic_file_mmap: % git grep generic_file_mmap | grep ^fs | awk -F/ '{print $2}' | uniq | xargs echo 9p adfs affs afs bfs ecryptfs exfat ext2 fat fuse hfs hfsplus hostfs hpfs jfs minix nfs ntfs ntfs3 omfs ramfs reiserfs smb sysv ubifs ufs vboxsf - Ted