Date: Tue, 17 Apr 2012 23:22:19 +0300 From: Andriy Gapon <avg@FreeBSD.org> To: John Baldwin <jhb@FreeBSD.org> Cc: freebsd-fs@FreeBSD.org, freebsd-hackers@FreeBSD.org Subject: Re: [review request] zfsboot/zfsloader: support accessing filesystems within a pool Message-ID: <4F8DD0FB.7000907@FreeBSD.org> In-Reply-To: <201204160956.21148.jhb@freebsd.org> References: <4F8999D2.1080902@FreeBSD.org> <4F89B567.6090008@FreeBSD.org> <201204160956.21148.jhb@freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
on 16/04/2012 16:56 John Baldwin said the following: > On Saturday, April 14, 2012 1:35:35 pm Andriy Gapon wrote: >> on 14/04/2012 18:37 Andriy Gapon said the following: >>> >>> I would like to ask for a review and/or testing of the following three patches: >>> http://people.freebsd.org/~avg/zfsboot.patches.diff >>> >>> These patches add support for booting from an arbitrary filesystem of any >>> detected ZFS pool. A filesystem could be selected in zfsboot and thus will >>> affectfrom where zfsloader would be loaded. zfsboot passes information about >>> the boot pool and filesystem to zfsloader, which uses those for loaddev and >>> default value of currdev. A different pool+filesystem could be selected in >>> zfsloader for booting kernel. Also if vfs.root.mountfrom is not explicitly set >>> and is not derived from fstab, then it gets set to the selected boot filesystem. >> >> A note for prospective testers: the patched loader expect to be started by the >> patched zfs boot as it passes an additional parameter for a filesystem guid. >> I should probably add some way to distinguish between the older and newer zfs >> boot blocks. Maybe an extra bit in bootflags? What do you think? > > An extra bit (similar to existing flags for detecting PXE and CD booting) > sounds fine to me. (Note, I'm only replying to the question, have not looked > at patches yet). I hope that you will :-) We already have a flag for ZFS (KARGS_FLAGS_ZFS, 0x4). So the new flag could be named something ZFS-specific (as silly as KARGS_FLAGS_ZFS2) or something more general such as KARGS_FLAGS_32_BYTES meaning that the total size of arguments area is 32 bytes (as opposed to 24 previously). -- Andriy Gapon
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4F8DD0FB.7000907>