postcopy+vhost-user/shared ram

From: "Dr. David Alan Gilbert" <[email protected]>

This set enables postcopy migration with shared memory to a vhost user process.
It's based off current head.

Testing is mostly performed with dpdk, with corresponding modifications by
Maxime.

v6 is a rebase on top of Michael's PCI world; this took some merging
because of Jay Zhou's 'vhost: used_memslots refactoring', which needed a bit of a change to 'vhost+postcopy: Stash RAMBlock and offset' (which I dropped the Review-by off)
and 'postcopy+vhost-user: Split set_mem_table for postcopy' (which I kept it, since the change is mostly contextual).

And I removed a blank line at the end of a patch.

Dave

Dr. David Alan Gilbert (29):
migrate: Update ram_block_discard_range for shared qemu_ram_block_host_offset
postcopy: use UFFDIO_ZEROPAGE only when available
postcopy: Add notifier chain
postcopy: Add vhost-user flag for postcopy and check it
vhost-user: Add 'VHOST_USER_POSTCOPY_ADVISE' message
libvhost-user: Support sending fds back to qemu
libvhost-user: Open userfaultfd
postcopy: Allow registering of fd handler vhost+postcopy: Register shared ufd with postcopy vhost+postcopy: Transmit 'listen' to slave postcopy+vhost-user: Split set_mem_table for postcopy migration/ram: ramblock_recv_bitmap_test_byte_offset libvhost-user+postcopy: Register new regions with the ufd vhost+postcopy: Send address back to qemu vhost+postcopy: Stash RAMBlock and offset vhost+postcopy: Helper to send requests to source for shared pages vhost+postcopy: Resolve client address
postcopy: helper for waking shared
postcopy: postcopy_notify_shared_wake
vhost+postcopy: Add vhost waker
vhost+postcopy: Call wakeups
libvhost-user: mprotect & madvises for postcopy
vhost-user: Add VHOST_USER_POSTCOPY_END message vhost+postcopy: Wire up POSTCOPY_END notify
vhost: Huge page align and merge
postcopy: Allow shared memory
libvhost-user: Claim support for postcopy
postcopy shared docs

 contrib/libvhost-user/libvhost-user.c | 302 ++++++++++++++++++++++++-
 contrib/libvhost-user/libvhost-user.h |  11 +
 docs/devel/migration.rst              |  41 ++++
 docs/interop/vhost-user.txt           |  52 +++++
 exec.c                                |  86 ++++++--
 hw/virtio/trace-events                |  16 +-
 hw/virtio/vhost-user.c                | 403 +++++++++++++++++++++++++++++++++-
 hw/virtio/vhost.c                     |  66 +++++-
 include/exec/cpu-common.h             |   4 +
 migration/migration.c                 |   6 +
 migration/migration.h                 |   4 +
 migration/postcopy-ram.c              | 353 +++++++++++++++++++++++------
 migration/postcopy-ram.h              |  73 ++++++
 migration/ram.c                       |   5 +
 migration/ram.h                       |   1 +
 migration/savevm.c                    |  13 ++
 migration/trace-events                |   6 +
 trace-events                          |   3 +-
 vl.c                                  |   2 +
 19 files changed, 1351 insertions(+), 96 deletions(-)

2.14.3