git: kernel - Even more buffer cache / VM coherency work

[Matthew Dillon]

    The development kernel should be stable with this last commit.
    Overnight stress tests ran successfully on UFS, NFS, and HAMMER.

    Please leave vm.swap_burst_read disabled (0), it is not yet operational.

    This essentially completes the switchover of the BUF/BIO/VM coherency
    code to the new API.  The major filesystems (UFS, NFS, HAMMER) now all
    use the generic getpages and putpages code, and now all use the new
    file truncation and file extension API.

    I have a few other patches under test in unrelated subsystems.  I
    noticed a syncache panic yesterday so I am working on a fix for
    that, and a few other minor items.

						-Matt