Re: [Avf-fuse-dev] [PATCH] add per-file DIRECT_IO

[Miklos S. <mi...@sz...>]

> I figured I might as well go ahead and code it up. Adds a flags field to
> open_outargs. Kernel module copies that into struct fuse_file. All checks
> for FUSE_DIRECT_IO look in file_private->flags as well as fc->flags.

Looks good.

> User filesystem sets the flag when open returns >0.

I don't really like this: it's a subtle changing of the semantics.  We
need to extend the open/read/write/close function arguments anyway, if
we want the filesystem to know about the file descriptor.  So what
about adding an extra parameter to these functions.  This would be a
pointer to a structure something like this:

struct fuse_file_param {
       int fd;
       int flags;
};

Most filesystems would just ignore this (libfuse would reset the
values to 0).

Thoughts?

Miklos