Merge remote-tracking branch 'remotes/dgilbert/tags/pull-migration-20210208a' into staging

Migration pull 2021-02-08

v2
  Dropped vmstate: Fix memory leak in vmstate_handle_alloc
    Broke on Power
  Added migration: only check page size match if RAM postcopy is enabled

# gpg: Signature made Mon 08 Feb 2021 11:28:14 GMT
# gpg:                using RSA key 45F5C71B4A0CB7FB977A9FA90516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>" [full]
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A  9FA9 0516 331E BC5B FDE7

* remotes/dgilbert/tags/pull-migration-20210208a: (27 commits)
  migration: only check page size match if RAM postcopy is enabled
  migration: introduce snapshot-{save, load, delete} QMP commands
  iotests: fix loading of common.config from tests/ subdir
  iotests: add support for capturing and matching QMP events
  migration: introduce a delete_snapshot wrapper
  migration: wire up support for snapshot device selection
  migration: control whether snapshots are ovewritten
  block: rename and alter bdrv_all_find_snapshot semantics
  block: allow specifying name of block device for vmstate storage
  block: add ability to specify list of blockdevs during snapshot
  migration: stop returning errno from load_snapshot()
  migration: Make save_snapshot() return bool, not 0/-1
  block: push error reporting into bdrv_all_*_snapshot functions
  migration: Display the migration blockers
  migration: Add blocker information
  migration: Fix a few absurdly defective error messages
  migration: Fix cache_init()'s "Failed to allocate" error messages
  migration: Clean up signed vs. unsigned XBZRLE cache-size
  migration: Fix migrate-set-parameters argument validation
  migration: introduce 'userfaultfd-wrlat.py' script
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

4 files changed, 104 insertions, 9 deletions

diff --git a/include/block/snapshot.h b/include/block/snapshot.h
index b0fe42993d..940345692f 100644
--- a/include/block/snapshot.h
+++ b/include/block/snapshot.h
@@ -25,7 +25,7 @@
 #ifndef SNAPSHOT_H
 #define SNAPSHOT_H
 
-
+#include "qapi/qapi-builtin-types.h"
 
 #define SNAPSHOT_OPT_BASE       "snapshot."
 #define SNAPSHOT_OPT_ID         "snapshot.id"
@@ -77,17 +77,26 @@ int bdrv_snapshot_load_tmp_by_id_or_name(BlockDriverState *bs,
  * These functions will properly handle dataplane (take aio_context_acquire
  * when appropriate for appropriate block drivers */
 
-bool bdrv_all_can_snapshot(BlockDriverState **first_bad_bs);
-int bdrv_all_delete_snapshot(const char *name, BlockDriverState **first_bsd_bs,
+bool bdrv_all_can_snapshot(bool has_devices, strList *devices,
+                           Error **errp);
+int bdrv_all_delete_snapshot(const char *name,
+                             bool has_devices, strList *devices,
                              Error **errp);
-int bdrv_all_goto_snapshot(const char *name, BlockDriverState **first_bad_bs,
+int bdrv_all_goto_snapshot(const char *name,
+                           bool has_devices, strList *devices,
                            Error **errp);
-int bdrv_all_find_snapshot(const char *name, BlockDriverState **first_bad_bs);
+int bdrv_all_has_snapshot(const char *name,
+                          bool has_devices, strList *devices,
+                          Error **errp);
 int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
                              BlockDriverState *vm_state_bs,
                              uint64_t vm_state_size,
-                             BlockDriverState **first_bad_bs);
+                             bool has_devices,
+                             strList *devices,
+                             Error **errp);
 
-BlockDriverState *bdrv_all_find_vmstate_bs(void);
+BlockDriverState *bdrv_all_find_vmstate_bs(const char *vmstate_bs,
+                                           bool has_devices, strList *devices,
+                                           Error **errp);
 
 #endif
diff --git a/include/exec/memory.h b/include/exec/memory.h
index c6ce74fb79..e58c09f130 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -149,6 +149,14 @@ typedef struct IOMMUTLBEvent {
 /* RAM is a persistent kind memory */
 #define RAM_PMEM (1 << 5)
 
+
+/*
+ * UFFDIO_WRITEPROTECT is used on this RAMBlock to
+ * support 'write-tracking' migration type.
+ * Implies ram_state->ram_wt_enabled.
+ */
+#define RAM_UF_WRITEPROTECT (1 << 6)
+
 static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn,
                                        IOMMUNotifierFlag flags,
                                        hwaddr start, hwaddr end,
diff --git a/include/migration/snapshot.h b/include/migration/snapshot.h
index c85b6ec75b..e72083b117 100644
--- a/include/migration/snapshot.h
+++ b/include/migration/snapshot.h
@@ -15,7 +15,50 @@
 #ifndef QEMU_MIGRATION_SNAPSHOT_H
 #define QEMU_MIGRATION_SNAPSHOT_H
 
-int save_snapshot(const char *name, Error **errp);
-int load_snapshot(const char *name, Error **errp);
+#include "qapi/qapi-builtin-types.h"
+
+/**
+ * save_snapshot: Save an internal snapshot.
+ * @name: name of internal snapshot
+ * @overwrite: replace existing snapshot with @name
+ * @vmstate: blockdev node name to store VM state in
+ * @has_devices: whether to use explicit device list
+ * @devices: explicit device list to snapshot
+ * @errp: pointer to error object
+ * On success, return %true.
+ * On failure, store an error through @errp and return %false.
+ */
+bool save_snapshot(const char *name, bool overwrite,
+                   const char *vmstate,
+                   bool has_devices, strList *devices,
+                   Error **errp);
+
+/**
+ * load_snapshot: Load an internal snapshot.
+ * @name: name of internal snapshot
+ * @vmstate: blockdev node name to load VM state from
+ * @has_devices: whether to use explicit device list
+ * @devices: explicit device list to snapshot
+ * @errp: pointer to error object
+ * On success, return %true.
+ * On failure, store an error through @errp and return %false.
+ */
+bool load_snapshot(const char *name,
+                   const char *vmstate,
+                   bool has_devices, strList *devices,
+                   Error **errp);
+
+/**
+ * delete_snapshot: Delete a snapshot.
+ * @name: path to snapshot
+ * @has_devices: whether to use explicit device list
+ * @devices: explicit device list to snapshot
+ * @errp: pointer to error object
+ * On success, return %true.
+ * On failure, store an error through @errp and return %false.
+ */
+bool delete_snapshot(const char *name,
+                    bool has_devices, strList *devices,
+                    Error **errp);
 
 #endif
diff --git a/include/qemu/userfaultfd.h b/include/qemu/userfaultfd.h
new file mode 100644
index 0000000000..6b74f92792
--- /dev/null
+++ b/include/qemu/userfaultfd.h
@@ -0,0 +1,35 @@
+/*
+ * Linux UFFD-WP support
+ *
+ * Copyright Virtuozzo GmbH, 2020
+ *
+ * Authors:
+ *  Andrey Gruzdev   <andrey.gruzdev@virtuozzo.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 USERFAULTFD_H
+#define USERFAULTFD_H
+
+#include "qemu/osdep.h"
+#include "exec/hwaddr.h"
+#include <linux/userfaultfd.h>
+
+int uffd_query_features(uint64_t *features);
+int uffd_create_fd(uint64_t features, bool non_blocking);
+void uffd_close_fd(int uffd_fd);
+int uffd_register_memory(int uffd_fd, void *addr, uint64_t length,
+        uint64_t mode, uint64_t *ioctls);
+int uffd_unregister_memory(int uffd_fd, void *addr, uint64_t length);
+int uffd_change_protection(int uffd_fd, void *addr, uint64_t length,
+        bool wp, bool dont_wake);
+int uffd_copy_page(int uffd_fd, void *dst_addr, void *src_addr,
+        uint64_t length, bool dont_wake);
+int uffd_zero_page(int uffd_fd, void *addr, uint64_t length, bool dont_wake);
+int uffd_wakeup(int uffd_fd, void *addr, uint64_t length);
+int uffd_read_events(int uffd_fd, struct uffd_msg *msgs, int count);
+bool uffd_poll_events(int uffd_fd, int tmo);
+
+#endif /* USERFAULTFD_H */