On Fri, 2007-08-31 at 10:01 -0700, Linus Torvalds wrote:
I agree for the cases where you can use bind mounts, however you can't
always do that.
Consider the fairly common setup where /foo, /foo/a, /foo/b are all on
the same filesystem on the server, but only /foo/a and /foo/b are
exported.
There can be plenty of files that are contain hard links in both
directories, but because you cannot mount the parent, /foo, you will not
be able to ensure that these common files are cached to the same inode
(which they need to be).
IOW: with this scenario, you can't ensure that local posix semantics
hold (i.e. that if my client is the only user, then the filesystem will
behave as if it were a posix filesystem). That would be a major
regression.
(a) I'm not sure that is true: see (b).
(b) You gain remount clarity at the expense of local posix filesystem
correctness.
Trond
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