ramfs: Switch from an embedded to a separately allocated small buffer.

This saves 16 bytes in the class vs. the old size, but more importantly
allows us to avoid allocating VMCaches and wasting an entire page for
any attribute larger than 32 bytes; instead, attributes can be up to
1024 bytes before we allocate a full page for them.

Unfortunately small files cannot take advantage of this optimization
right now as the cache is always used for them. I added a TODO about
this.

ramfs: Set the vnode's cache object when opening files.

Now it is possible to run applications, do Git checkouts, etc.
on a ramfs (and those seem to work just fine -- a git checkout
followed by a git fsck both succeeded.)

ramfs: Overhaul block allocation to use a VMCache and physical pages.

This is a massive efficiency improvement as well as a large address
space usage savings. It also paves the way for file_map() support...

ramfs: Add MIT license header to all files lacking copyright info.

OK'ed by Ingo via email.

Mmh, apparently I have to check the copied directory itself in first.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20345 a95241bf-73f2-0310-859d-f6bbb57e9c96

Mmh, apparently I have to check the copied directory itself in first.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20345 a95241bf-73f2-0310-859d-f6bbb57e9c96