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authorJuan Quintela <quintela@redhat.com>2017-04-20 13:12:24 +0200
committerJuan Quintela <quintela@redhat.com>2017-05-04 10:40:30 +0200
commitbe07b0ace82b0f23bee194de9e4481c308645376 (patch)
tree214f94653990ac6d759b2bf5fd69e00f5d3addc2 /migration/postcopy-ram.h
parent6683061873095ad3f34f73bd32553c1d2c559e82 (diff)
migration: Move postcopy-ram.h to migration/
It is internal to migration, not intended for other users. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Diffstat (limited to 'migration/postcopy-ram.h')
-rw-r--r--migration/postcopy-ram.h91
1 files changed, 91 insertions, 0 deletions
diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h
new file mode 100644
index 0000000000..4c25f03be2
--- /dev/null
+++ b/migration/postcopy-ram.h
@@ -0,0 +1,91 @@
+/*
+ * Postcopy migration for RAM
+ *
+ * Copyright 2013 Red Hat, Inc. and/or its affiliates
+ *
+ * Authors:
+ * Dave Gilbert <dgilbert@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+#ifndef QEMU_POSTCOPY_RAM_H
+#define QEMU_POSTCOPY_RAM_H
+
+/* Return true if the host supports everything we need to do postcopy-ram */
+bool postcopy_ram_supported_by_host(void);
+
+/*
+ * Make all of RAM sensitive to accesses to areas that haven't yet been written
+ * and wire up anything necessary to deal with it.
+ */
+int postcopy_ram_enable_notify(MigrationIncomingState *mis);
+
+/*
+ * Initialise postcopy-ram, setting the RAM to a state where we can go into
+ * postcopy later; must be called prior to any precopy.
+ * called from ram.c's similarly named ram_postcopy_incoming_init
+ */
+int postcopy_ram_incoming_init(MigrationIncomingState *mis, size_t ram_pages);
+
+/*
+ * At the end of a migration where postcopy_ram_incoming_init was called.
+ */
+int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis);
+
+/*
+ * Userfault requires us to mark RAM as NOHUGEPAGE prior to discard
+ * however leaving it until after precopy means that most of the precopy
+ * data is still THPd
+ */
+int postcopy_ram_prepare_discard(MigrationIncomingState *mis);
+
+/*
+ * Called at the start of each RAMBlock by the bitmap code.
+ * Returns a new PDS
+ */
+PostcopyDiscardState *postcopy_discard_send_init(MigrationState *ms,
+ const char *name);
+
+/*
+ * Called by the bitmap code for each chunk to discard.
+ * May send a discard message, may just leave it queued to
+ * be sent later.
+ * @start,@length: a range of pages in the migration bitmap in the
+ * RAM block passed to postcopy_discard_send_init() (length=1 is one page)
+ */
+void postcopy_discard_send_range(MigrationState *ms, PostcopyDiscardState *pds,
+ unsigned long start, unsigned long length);
+
+/*
+ * Called at the end of each RAMBlock by the bitmap code.
+ * Sends any outstanding discard messages, frees the PDS.
+ */
+void postcopy_discard_send_finish(MigrationState *ms,
+ PostcopyDiscardState *pds);
+
+/*
+ * Place a page (from) at (host) efficiently
+ * There are restrictions on how 'from' must be mapped, in general best
+ * to use other postcopy_ routines to allocate.
+ * returns 0 on success
+ */
+int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
+ size_t pagesize);
+
+/*
+ * Place a zero page at (host) atomically
+ * returns 0 on success
+ */
+int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
+ size_t pagesize);
+
+/*
+ * Allocate a page of memory that can be mapped at a later point in time
+ * using postcopy_place_page
+ * Returns: Pointer to allocated page
+ */
+void *postcopy_get_tmp_page(MigrationIncomingState *mis);
+
+#endif