:Tony Finch <f...@demon.net> wrote:
:
:Well, in the absence of any comments I hacked around a bit and ended
:up with the following patch (against 3.3-RC), which permits the same
:block device to be mounted read-only more than once. The motivation
:for this is to permit multiple chrooted environments to share the same
:/usr partition.
:
:Some things I wonder about this change is whether the mounts will share
:the same pages in the buffer cache, and whether the resource
:accounting is still right. I've subtly funted the meaning of
:v_specmountpoint when multiple mounts happen; does this matter?
:
:Tony.
:-- 
:f.a.n.finch    d...@dotat.at    f...@demon.net    e pluribus unix

    Hmm... well, there is a problem here.  I believe this will allow
    you to open the underlying block device read-only as well as mount
    the filesystem read-only.  This will confuse the buffer cache badly.

    Also, this may not be the best place to put the code.  It make sense
    to be able to mount a block device multiple times in a read-only
    fashion, but the code should be in the open for the block device
    rather then in UFS/FFS, so it can be used with other filesystems
    and for other purposes.

                                        -Matt


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