On Thu, Aug 16, 2012 at 10:24:48AM +0400, Cyrill Gorcunov wrote: > > > > On the other hand, if you want a real filehandle then wouldn't you want > > > > to e.g. call the filesystem's ->encode_fh() if necessary, as > > > > exportfs_encode_fh() does? > > > > > > Well, one of the problem I hit when I've been trying to use encode_fh > > > is that every new implementation of encode_fh will require some size > > > (even unknown) in buffer where encoded data pushed. Correct me please > > > if I'm wrong. But with export_encode_inode_fh there is a small buffer > > > with pretty known size needed on stack needed for printing data in > > > fdinfo. > > > > You can just give encode_fh a too-small data and let it fail if it's not > > big enough. > > > > (In practice I think everyone supports NFSv3 filehandles which have a > > maximum size of 64 bytes.) > > I'll think about it, thanks! Hi Bruce, thinking a bit more I guess using general encode_fh is not that convenient since it operates with dentries while our fdinfo output deals with inodes. Thus I should either provide some new encode_fh variant which would deal with inodes directly without "parents". Which doesn't look for me anyhow better than the new export_encode_inode_fh helper. After all, if the use of encode_fh become a mandatory rule we can easily extend fsnotify fdinfo output to support new scheme without breaking user space, because output looks like | fhandle-type: 1 f_handle: 49b1060023552153 (ie if something is changed than these fields will be simply updated). Or maybe I miss something? Cyrill -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
