From: "Michael R. Hines" <mrhi...@us.ibm.com>
These are the prototypes and implementation of new hooks that
RDMA takes advantage of to perform dynamic page registration.
An optional hook is also introduced for a custom function
to be able to override the default save_page function.
Also included are the prototypes and accessor methods used by
arch_init.c which invoke funtions inside savevm.c to call out
to the hooks that may or may not have been overridden
inside of QEMUFileOps.
Signed-off-by: Michael R. Hines <mrhi...@us.ibm.com>
---
include/migration/migration.h | 16 +++++++++
include/migration/qemu-file.h | 30 +++++++++++++++++
savevm.c | 75 +++++++++++++++++++++++++++++++++++++----
3 files changed, 114 insertions(+), 7 deletions(-)
diff --git a/include/migration/migration.h b/include/migration/migration.h
index e2acec6..f6df8d1 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -21,6 +21,7 @@
#include "qapi/error.h"
#include "migration/vmstate.h"
#include "qapi-types.h"
+#include "exec/cpu-common.h"
struct MigrationParams {
bool blk;
@@ -127,4 +128,19 @@ int migrate_use_xbzrle(void);
int64_t migrate_xbzrle_cache_size(void);
int64_t xbzrle_cache_resize(int64_t new_size);
+
+void ram_control_before_iterate(QEMUFile *f, uint32_t flags);
+void ram_control_after_iterate(QEMUFile *f, uint32_t flags);
+void ram_control_load_hook(QEMUFile *f, uint32_t flags);
+
+/* Whenever this is found in the data stream, the flags
+ * will be passed to ram_control_load_hook in the incoming-migration
+ * side. This lets before_ram_iterate/after_ram_iterate add
+ * transport-specific sections to the RAM migration data.
+ */
+#define RAM_SAVE_FLAG_HOOK 0x80
+
+size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
+ ram_addr_t offset, size_t size);
+
#endif
diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h
index 623c434..3f59d02 100644
--- a/include/migration/qemu-file.h
+++ b/include/migration/qemu-file.h
@@ -23,6 +23,7 @@
*/
#ifndef QEMU_FILE_H
#define QEMU_FILE_H 1
+#include "exec/cpu-common.h"
/* This function writes a chunk of data to a file at the given position.
* The pos argument can be ignored if the file is only being used for
@@ -57,12 +58,39 @@ typedef int (QEMUFileGetFD)(void *opaque);
typedef ssize_t (QEMUFileWritevBufferFunc)(void *opaque, struct iovec *iov,
int iovcnt);
+/*
+ * This function provides hooks around different
+ * stages of RAM migration.
+ */
+typedef int (QEMURamHookFunc)(QEMUFile *f, void *opaque, uint32_t flags);
+
+/*
+ * Constants used by ram_control_* hooks
+ */
+#define RAM_CONTROL_SETUP 0
+#define RAM_CONTROL_ROUND 1
+#define RAM_CONTROL_HOOK 2
+#define RAM_CONTROL_FINISH 3
+
+/*
+ * This function allows override of where the RAM page
+ * is saved (such as RDMA, for example.)
+ */
+typedef size_t (QEMURamSaveFunc)(QEMUFile *f, void *opaque,
+ ram_addr_t block_offset,
+ ram_addr_t offset,
+ size_t size);
+
typedef struct QEMUFileOps {
QEMUFilePutBufferFunc *put_buffer;
QEMUFileGetBufferFunc *get_buffer;
QEMUFileCloseFunc *close;
QEMUFileGetFD *get_fd;
QEMUFileWritevBufferFunc *writev_buffer;
+ QEMURamHookFunc *before_ram_iterate;
+ QEMURamHookFunc *after_ram_iterate;
+ QEMURamHookFunc *hook_ram_load;
+ QEMURamSaveFunc *save_page;
} QEMUFileOps;
QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops);
@@ -81,6 +109,8 @@ void qemu_put_byte(QEMUFile *f, int v);
*/
void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, int size);
+bool qemu_file_mode_is_not_valid(const char *mode);
+
static inline void qemu_put_ubyte(QEMUFile *f, unsigned int v)
{
qemu_put_byte(f, (int)v);
diff --git a/savevm.c b/savevm.c
index b1d8988..60918b3 100644
--- a/savevm.c
+++ b/savevm.c
@@ -409,14 +409,23 @@ static const QEMUFileOps socket_write_ops = {
.close = socket_close
};
-QEMUFile *qemu_fopen_socket(int fd, const char *mode)
+bool qemu_file_mode_is_not_valid(const char *mode)
{
- QEMUFileSocket *s = g_malloc0(sizeof(QEMUFileSocket));
-
if (mode == NULL ||
(mode[0] != 'r' && mode[0] != 'w') ||
mode[1] != 'b' || mode[2] != 0) {
fprintf(stderr, "qemu_fopen: Argument validity check failed\n");
+ return true;
+ }
+
+ return false;
+}
+
+QEMUFile *qemu_fopen_socket(int fd, const char *mode)
+{
+ QEMUFileSocket *s = g_malloc0(sizeof(QEMUFileSocket));
+
+ if (qemu_file_mode_is_not_valid(mode)) {
return NULL;
}
@@ -434,10 +443,7 @@ QEMUFile *qemu_fopen(const char *filename, const char
*mode)
{
QEMUFileStdio *s;
- if (mode == NULL ||
- (mode[0] != 'r' && mode[0] != 'w') ||
- mode[1] != 'b' || mode[2] != 0) {
- fprintf(stderr, "qemu_fopen: Argument validity check failed\n");
+ if (qemu_file_mode_is_not_valid(mode)) {
return NULL;
}
@@ -554,6 +560,61 @@ static void qemu_fflush(QEMUFile *f)
}
}
+void ram_control_before_iterate(QEMUFile *f, uint32_t flags)
+{
+ int ret = 0;
+
+ if (f->ops->before_ram_iterate) {
+ ret = f->ops->before_ram_iterate(f, f->opaque, flags);
+ if (ret < 0) {
+ qemu_file_set_error(f, ret);
+ }
+ }
+}
+
+void ram_control_after_iterate(QEMUFile *f, uint32_t flags)
+{
+ int ret = 0;
+
+ if (f->ops->after_ram_iterate) {
+ ret = f->ops->after_ram_iterate(f, f->opaque, flags);
+ if (ret < 0) {
+ qemu_file_set_error(f, ret);
+ }
+ }
+}
+
+void ram_control_load_hook(QEMUFile *f, uint32_t flags)
+{
+ int ret = 0;
+
+ if (f->ops->hook_ram_load) {
+ ret = f->ops->hook_ram_load(f, f->opaque, flags);
+ if (ret < 0) {
+ qemu_file_set_error(f, ret);
+ }
+ }
+}
+
+size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
+ ram_addr_t offset, size_t size)
+{
+ if (f->ops->save_page) {
+ int64_t bytes;
+ bytes = f->ops->save_page(f, f->opaque, block_offset, offset, size);
+
+ if (bytes >= 0) {
+ f->pos += bytes;
+ } else {
+ qemu_file_set_error(f, bytes);
+ }
+
+ return bytes;
+ }
+
+ return -1;
+}
+
static void qemu_fill_buffer(QEMUFile *f)
{
int len;
--
1.7.10.4
