[gsoc15] dynamically discover bes

[Prasad Joshi]

1. Fixed broken sort functionality
2. Printf compilation problem is fixed
3. Started working on multiple SPA support

Tasks for next week
================
Complete multiple SPA support.

- Prasad
On Aug 4, 2015 1:01 AM, "Prasad Joshi" <prasadjoshi.linux at gmail.com> wrote:

> Status Report
> ===========
> 1. Added flat zap support
> 2. Removed common, unnecessary code.
> 3. When machine bootsup, instead of waiting for a keypress to show
> bootmenu, now it is displayed as soon as machine starts. If no key is
> pressed, default BE is used for booting in 5 seconds
>
> Tasks for coming week
> ==================
> 1. Fix broken sort functionality
> 2. Fix util.c and libstand.a compilation problem
> 3. Special keys for example arrow keys, home, pageup etc aren't working
> till now
>
> On Tue, Jul 28, 2015 at 1:04 AM, Prasad Joshi
> <prasadjoshi.linux at gmail.com> wrote:
> > Status report
> > ==========
> > The BEs menu is working. With my code changes, when machine is booted
> > by default gptzfsboot tries to boot an active BE. However, if user
> > presses any key, the code finds out all BEs and displays menu for
> > selection to user. Once user selects a BE to boot from, appropriate
> > information is passed to next stage of boot loader.
> >
> > Tasks for coming week
> > =================
> > 1. I disabled some of the existing gptzfsboot code which handles
> > serial console. I will try to enable it again and check if menu
> > functionality works on serial console.
> >
> > Thanks and Regards,
> > Prasad
> >
> > On Sun, Jul 12, 2015 at 10:03 PM, Prasad Joshi
> > <prasadjoshi.linux at gmail.com> wrote:
> >> Status report for past two weeks
> >> =========================
> >> - Last two weeks I struggled to get non-active BE to boot completely -
> >> after zfs mount -a all files in /dev/ used to disappear. Finally
> >> disabling canmount property on each dataset helped me boot non-active
> >> BEs.
> >>
> >> - I added code to pass mountpoint information from gptzfsboot to
> >> zfsloader, then from zfsloader I could set vfs.root.mountfrom env
> >> variable.
> >>
> >> - Added code to find timestamp of each BE clone, with this change BEs
> >> could now be sorted on either timestamp, BE name, or object number
> >>
> >> Tasks For coming week
> >> ==================
> >> 1. start the initial implementation of menu functionality.
> >>
> >> On Tue, Jun 30, 2015 at 7:26 PM, Prasad Joshi
> >> <prasadjoshi.linux at gmail.com> wrote:
> >>> Week 5 Update
> >>>
> >>> - I did not work on GSoC for 3 days in this week. Had to attend full
> >>> day sessions in the University.
> >>> - Last week I was faced with a problem with booting alternate
> >>> (non-active) BE. Plan in this week was to locate the problem. It seems
> >>> like, during bootup zfsloader needs to initialize libzfs library. The
> >>> libzfs library initialization fails because '/dev/zfs' cannot be
> >>> opened. I verified the zfs kernel modules, which create the device are
> >>> loaded. I think, and as suggested by mentor, I will have to set
> >>> vfs.root.mountfrom environment variable during bootup.
> >>>
> >>> Thanks and Regards,
> >>> Prasad
> >>>
> >>> On Mon, Jun 22, 2015 at 11:42 PM, Prasad Joshi
> >>> <prasadjoshi.linux at gmail.com> wrote:
> >>>> Week 4 update
> >>>>
> >>>> - I have been able to discover BEs on console. I could detect active
> BE.
> >>>> Created list of BEs. Code to sort BEs on object number, name, or
> timestamp
> >>>> is added.
> >>>>
> >>>> - I am able to boot from nonactive BE to some extent. At the moment,
> code
> >>>> requires me to enter BE number to boot from.
> >>>>
> >>>> Tasks next week
> >>>> 1. Identify a problem with be bootup.
> >>>> 2. Pass mount point info through env variable to loader.
> >>>> 3. Start with console based menu.
> >>>>
> >>>> Thanks and Regards,
> >>>> Prasad
> >>>>
> >>>> On Jun 15, 2015 7:48 PM, "Prasad Joshi" <prasadjoshi.linux at gmail.com>
> wrote:
> >>>>>
> >>>>> Week 3 status
> >>>>> ==========
> >>>>> After understanding on disk representation of snapshots and clones, I
> >>>>> have been able to find names of the BEs created using beadm command.
> I
> >>>>> could print the BE names on console.
> >>>>>
> >>>>> The next task would be to convert BE names to object numbers, create
> >>>>> list of BEs.
> >>>>>
> >>>>> Thanks and Regards,
> >>>>> Prasad
> >>>>>
> >>>>> On Tue, Jun 9, 2015 at 6:36 AM, Prasad Joshi
> >>>>> <prasadjoshi.linux at gmail.com> wrote:
> >>>>> > Last week I mostly worked on understanding beadm and gptzfsboot
> code
> >>>>> >
> >>>>> > beadm create prepares new BE by creating a snapshot and clone of
> that
> >>>>> > snapshot. beadm activate command sets bootfs property of the POOL.
> >>>>> > bootfs property contains object number of active dataset object.
> >>>>> > During bootup gptzfsboot probes all the disks, creating SPA for any
> >>>>> > valid pool. gptzfsboot assumes the first pool it finds as a primary
> >>>>> > pool, it then reads meta object set, then tries to find object
> nunber
> >>>>> > of active dataset object either through
> >>>>> > a. bootfs - it would be set if BE was already created
> >>>>> > b. mos->properties_zap->root_dataset->dd_head_dataset_obj (through
> >>>>> > root_datasets bonus buffer)
> >>>>> > Once the object number is obtaind gptzfsboot mounts the dataset.
> >>>>> >
> >>>>> > After mounting, few files are looked up like /boot/config or
> >>>>> > /boot.config for presense of boot command (did not went into
> details
> >>>>> > of this). Then (if keyboard is not hit), gptzfsboot execs
> >>>>> > /boot/zfsloader. If gptzfsboot is interrupted by keyboard, then it
> >>>>> > displays default BE or POOL it is trying to boot from (using
> >>>>> > zfs_rlookup() to map active dataset object to string BE name).
> Though
> >>>>> > I haven't checked this but through serial console user would be
> >>>>> > allowed to enter other pool or BE to boot from.
> >>>>> >
> >>>>> > I could not go into details of how gptzfsboot reads
> /boot/zfsloader from
> >>>>> > disk.
> >>>>> >
> >>>>> > Pending Tasks
> >>>>> > =============
> >>>>> > 1. Understand upon keyboard interruption, how user entered zfs
> paths
> >>>>> > (format [zfs:pool/filesystem:][/path/to/loader]) are converted in
> >>>>> > object numbers?
> >>>>> > 2. Learn ZFS on disk format in more details so as to identify
> active
> >>>>> > dataset object numbers of all BEs. Once the object numbers are
> >>>>> > available, I can use zfs_rlookup() function to map object number to
> >>>>> > printable pool name.
> >>>>> > 3. Prepare library for console based menu.
> >>>>> >
> >>>>> > Plan for next week
> >>>>> > ==================
> >>>>> > Pending task 2 above
>