This patch series tries to introduce a mechanism using side channel pipe for RAM via SCM_RIGHTS with unix domain socket protocol migration.
This side channel is used for the page flipping by vmsplice, which is the internal mechanism for localhost migration that we are trying to add to QEMU. The backgroud info and previous patch series for reference, Localhost migration http://lists.nongnu.org/archive/html/qemu-devel/2013-08/msg02916.html migration: Introduce side channel for RAM http://lists.gnu.org/archive/html/qemu-devel/2013-09/msg04043.html I have picked patches from the localhost migration series and rebased it on the series of side channel, now it is a complete series that passed the basic test. Please let me know if there is anything needs to be fixed or improved. Your suggestions and comments are very welcome, and thanks for Paolo for his review and useful suggestions. Changes since V1: Address suggestions from Paolo Bonzini including: - Use Unix socket QEMUFile as basis of code and adjust the way of overriding RDMA hooks. - Involve the vmsplice for page flipping. - Add new RunState RUN_STATE_FLIPPING_MIGRATE and add it to runstate_needs_reset() for the adjustment of the current migration process with page flipping. Lei Li (17): rename is_active to is_block_active QAPI: introduce magration capability unix_page_flipping migration: add migrate_unix_page_flipping() qmp-command.hx: add missing docs for migration capabilites migration-local: add QEMUFileLocal with socket based QEMUFile migration-local: introduce qemu_fopen_socket_local() migration-local: add send_pipefd() migration-local: add recv_pipefd() migration-local: override before_ram_iterate to send pipefd savevm: adjust ram_control_save_page with page flipping migration-local: override save_page for page transmit migration-local: override hook_ram_load migration-unix: replace qemu_fopen_socket with qemu_fopen_socket_local add new RanState RAN_STATE_FLIPPING_MIGRATE migration-unix: page flipping support on unix outgoing migration: adjust migration_thread() process for unix_page_flipping hmp: better fomat for info migrate_capabilities Makefile.target | 1 + block-migration.c | 2 +- migration-local.c | 512 ++++++++++++++++++++++++++++++++++++++++++ hmp.c | 5 +- include/migration/migration.h | 3 + include/migration/qemu-file.h | 2 + include/migration/vmstate.h | 2 +- migration-unix.c | 27 ++- migration.c | 18 +- qapi-schema.json | 18 +- qmp-commands.hx | 8 + savevm.c | 21 +- vl.c | 12 +- 13 files changed, 624 insertions(+), 27 deletions(-) create mode 100644 migration-local.c