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Rich Freeman posted on Sun, 15 Jul 2012 14:48:55 -0400 as excerpted: |
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> Giving it a little thought, the simplest tmpfs-based root would be one |
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> that defines a tarball as a the root. The system would create a tmpfs, |
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> extract the tarball to it, and then use the existing fstab-sys module to |
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> mount stuff on top of that. This gives you the option of actually |
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> putting some content in the tarball, or just storing an empty directory |
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> structure in it. A tarball would let you set permissions/etc and be a |
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> bit more generic than writing a custom script. If you wrote a module to |
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> do this I wouldn't be suprised if upstream let you merge it. You'd just |
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> need to define some kind of sane syntax for it |
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> (root=TAR=path...to...tarball - though how a path works with nothing |
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> mounted you'd have to define). Maybe you define the tarball at |
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> initramfs creation (as is done with fstab.sys and mdadm.conf). |
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Tarball is an interesting idea I hadn't considered. At first blush I |
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like it. =:^) |
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Thinking in that direction does stimulate yet another idea, tho. What |
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about a squashfs root? AFAIK squashfs is read-only at use time, thus |
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enforcing actually mounting something else to write anything, eliminating |
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many of the down sides of sticking with the initial ramfs root, but it |
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would allow the same flexibility in terms of sticking whatever into it at |
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create-time, while only taking the memory necessary for what's actually |
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stuck in it at create-time. I /think/ it's swappable, too, which would |
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give me some flexibility in terms of letting more stuff be added at |
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create-time without having to worry about it being locked in memory. And |
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I think squashfs is reasonably tested territory for this sort of thing, |
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given its use for live-media, etc. And it's in mainline now, too, which |
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is nice. =:^) I'll have to do some research and think about that a bit |
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more... |
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Definitely thanks for the tarball idea, as otherwise I'd probably have |
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not got out of my "box" and thought about squashfs. I'm probably missing |
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its downsides ATM, but you still broke my thinking out of the box! |
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-- |
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Duncan - List replies preferred. No HTML msgs. |
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"Every nonfree program has a lord, a master -- |
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and if you use the program, he is your master." Richard Stallman |
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