UP
See (p1,mig-intro) for
further information about the use of this key.
MIGRATE(0==>rc); Wait for migration
needed.
If there are no pages left to migrate this key waits
for the next migration to be needed and returns when it
is needed.
If there are pages left to be migrated the return is immediate.
The return code {rc} is the maximum number of pages to use
in the migration.
MIGRATE(1, ((2,countb),(4*countb,backup-list),
(2,counth),(4*counth,home-list))==>rc); Migrate these
addresses.
The counts are the number of entries in each list. The
lists consist of a cda from each nodepot or the cda of a
page. Each frame in the home-list {these should all represent
nodepots} is brought into real memory. Then the frames
from the backup-list are brought in from the backup swap
area. If the frame contains a page image it is written
into its home position, if it contains a node pot then all
the nodes in that nodepot that are the most recent versions
in the backup swap area and can be migrated to their home
nodepots are migrated.
When a home range is not available or a hard write error
occurs during migration, the page or node will be transferred
to the current backup area. Such a page is in limbo until
the bad medium is replaced. Data in limbo seems not much
less safe than ordinary data.
The user of MIGRATE is responsible for insuring that the
sum of his address space requirements and the pages required
to do the migration do not exceed the number returned by
MIGRATE 0.
Return code {rc} = 0 - All CDA's passed have been migrated.
Return Code {rc} = 1 - One of the home list was not a node
CDA, no migration performed.
Return Code {rc} = 2 - Sum of counts exceeds 1022 {size
of parameter page}, no migration performed.
MIGRATE(2==>rc,((4,cda),(8,loc1-loc2),...));
Get next directory segment.
MIGRATE(3==>rc,((4,first-cda),(4,last-cda),(4,loc))...)
Return mounted ranges.
This call returns information on the home ranges currently
mounted. The loc is the home location and consist of a 16
bit device address {the highest online path address} followed
by a 16 bit offset on device. The rc = 0.