For migration the last used pfn of a guest is needed to size the
logdirty bitmap and as an upper bound of the page loop. Unfortunately
there are pv-kernels advertising a much higher maximum pfn as they
are really using in order to support memory hotplug. This will lead
to allocation of much more memory in Xen tools during migration as
really needed.
Try to find the last used guest pfn of a pv-domu by scanning the p2m
tree from the last entry towards it's start and search for an entry
not being invalid.
Normally the mid pages of the p2m tree containing all invalid entries
are being reused, so we can just scan the top page for identical
entries and skip them but the first one.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
[ ijc -- added errno = E2BIG to one error path ]
Acked-by: Ian Campbell <ian.campbell@citrix.com>
And call it when a checkpoint record is found in the libxc stream.
Some parts of this patch have been based on patches from the COLO
series.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
---
v3: Named constants for the API
v2: Borrow sufficient fragments from several COLO patches to get
BROKEN_CHANNEL and checkpoint failover to function.
This is safe (as the variables will simply be unused), and is required
for correct compilation when midway through untangling the libxc/libxl
interaction.
The #define is left in place to highlight that the variables can be
removed once the untangling is complete.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
Split read/handle qemu info. The receiving of qemu info
should be done while we receive the migration stream,
handle_qemu will be called when the stream complete.
Otherwise, it will break Remus because read_record()
won't read qemu info and stream_complete will be called
at failover.
Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
The old code checks the callbacks "postcopy & checkpoint", if the
callbacks exists, it will call them. However this is unreliable, so
add this flag to explicitly indicate a checkpointed stream in the new
code. This is backward compatible with the legacy migration just don't
know this flag and will ignore it.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Yang Hongyang <yanghy@cn.fujitsu.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
[ ijc -- added discussion of legacy compat ]
There are some records which should only be sent once in the stream, and not
repeated for each checkpoint. {start,end}_of_stream() become per-checkpoint,
and a new start_of_stream() is introduced.
There is no resulting change record order, but the X86_PV_INFO record is
identified as once per stream. Currently the X86_PV_P2M_FRAMES record is as
well, but this is because of an implementation bug and can move back to being
on an as-needed basis when fixed.
In addition, a few minor adjustments of comments and layout.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Yang Hongyang <yanghy@cn.fujitsu.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
Restore the x86 HVM specific parts of a domain. This is the HVM_CONTEXT and
HVM_PARAMS records.
There is no need for any page localisation.
This also includes writing the trailing qemu save record to a file because
this is what libxc currently does. This is intended to be moved into libxl
proper in the future.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
Save the x86 HVM specific parts of the domain. This is considerably simpler
than an x86 PV domain. Only the HVM_CONTEXT and HVM_PARAMS records are
needed.
There is no need for any page normalisation.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
Restore the x86 PV specific parts. The X86_PV_INFO, the P2M_FRAMES,
SHARED_INFO, and VCPU context records.
The localise_page callback is called from the common PAGE_DATA code to convert
PFNs in page tables to MFNs.
Page tables are pinned and the guest's P2M is updated when the stream is
complete.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
Save the x86 PV specific parts of a domain. This is the X86_PV_INFO record,
the P2M_FRAMES, the X86_PV_SHARED_INFO, the three different VCPU context
records, and the MSR records.
The normalise_page callback used by the common code when writing the PAGE_DATA
records, converts MFNs in page tables to PFNs.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
Add the context structure used to keep state during the save/restore
process.
Define the set of architecture or domain type specific operations with a
set of callbacks (save_ops, and restore_ops).
Add common functions for writing records.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
Provide the C structures matching the binary (wire) format of the new
stream format. All header/record fields are naturally aligned and
explicit padding fields are used to ensure the correct layout (i.e.,
there is no need for any non-standard structure packing pragma or
attribute).
Provide some helper functions for converting types to string for
diagnostic purposes.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
For testing purposes, the environmental variable "XG_MIGRATION_V2" allows the
two save/restore codepaths to coexist, and have a runtime switch.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
Juergen Gross
Andrew Cooper
Yang Hongyang