When loading the metadata for a subarray (super_by_fd), we set
->subarray to be the name read from md/metadata_version so that
getinfo_super can return info about the correct array.
With this we can differentiate between a container and
an array within the container by looking at ->subarray[0].
Only one superswitch should be externally visible for each
general type. Others which handle different flavours
(e.g. container/data-array) should be internal only.
Using write_init_super to add a spare to an active array is quite
different to how it is used when creating an array.
It mostly works, but if we are adding two devices to an array,
then when we add the second, there are still traces of the first
which confuse write_init_super.
So get write_init_super to ignore those traces. Longer term, we
probably want to do this differently as for DDF, hot-adding to
an active array will have to be quite different - it will want to
write to all metadata, possibly via mdmon.
For arrays that don't have redundancy (raid0, linear etc), the
clean/dirty distinction doesn't mean anything. So always
'assume clean' for these arrays.
It is important that dup_super always returns an 'st' with the same
->ss and ->minor_version as the st that was passed.
This wasn't happening for 0.91 metadata (i.e. in the middle of a reshape).
for development only as console output can block leading to monitor deadlocks
in low mem situations
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
A spare device by definition will have raid_disk set to -1, but when
assembling the container we want this disk to by included.
Fixes a SIGSEGV when doing:
mdadm -A /dev/imsm -e imsm /dev/sd[b-e]
...where /dev/sde is marked as a global spare device
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
It is used later by container_content_imsm to determine set the
text_version of the member arrays.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Code in manager can now just call queue_metadata_update with a
(freeable) buf holding the update, and it will get passed to the
monitor and written out.
Since we made free_super a superswitch call, we need to be careful
that st is non NULL before calling st->ss->free_super(st).
Also when updating byteorder there is a chance of a similar NULL
deref.
'container_member' isn't really a well defined concept.
Each metadata might enumerate members differently, so just
let each format /mdX/YYYY as appropriate.
I want the metadata handler to have more control over the 'version',
particularly for arrays which are members of containers.
So discard st->text_version and instead use info->text_version
which getinfo_super can initialise.
Neil Brown
Chris Webb
Dan Williams