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-rw-r--r--block/Makefile.objs2
-rwxr-xr-xblock/blkreplay.c160
2 files changed, 161 insertions, 1 deletions
diff --git a/block/Makefile.objs b/block/Makefile.objs
index 3426a15ff7..44a5416225 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -4,7 +4,7 @@ block-obj-y += qed.o qed-gencb.o qed-l2-cache.o qed-table.o qed-cluster.o
block-obj-y += qed-check.o
block-obj-$(CONFIG_VHDX) += vhdx.o vhdx-endian.o vhdx-log.o
block-obj-y += quorum.o
-block-obj-y += parallels.o blkdebug.o blkverify.o
+block-obj-y += parallels.o blkdebug.o blkverify.o blkreplay.o
block-obj-y += block-backend.o snapshot.o qapi.o
block-obj-$(CONFIG_WIN32) += raw-win32.o win32-aio.o
block-obj-$(CONFIG_POSIX) += raw-posix.o
diff --git a/block/blkreplay.c b/block/blkreplay.c
new file mode 100755
index 0000000000..42f1813af1
--- /dev/null
+++ b/block/blkreplay.c
@@ -0,0 +1,160 @@
+/*
+ * Block protocol for record/replay
+ *
+ * Copyright (c) 2010-2016 Institute for System Programming
+ * of the Russian Academy of Sciences.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "block/block_int.h"
+#include "sysemu/replay.h"
+#include "qapi/error.h"
+
+typedef struct Request {
+ Coroutine *co;
+ QEMUBH *bh;
+} Request;
+
+/* Next request id.
+ This counter is global, because requests from different
+ block devices should not get overlapping ids. */
+static uint64_t request_id;
+
+static int blkreplay_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
+{
+ Error *local_err = NULL;
+ int ret;
+
+ /* Open the image file */
+ bs->file = bdrv_open_child(NULL, options, "image",
+ bs, &child_file, false, &local_err);
+ if (local_err) {
+ ret = -EINVAL;
+ error_propagate(errp, local_err);
+ goto fail;
+ }
+
+ ret = 0;
+fail:
+ if (ret < 0) {
+ bdrv_unref_child(bs, bs->file);
+ }
+ return ret;
+}
+
+static void blkreplay_close(BlockDriverState *bs)
+{
+}
+
+static int64_t blkreplay_getlength(BlockDriverState *bs)
+{
+ return bdrv_getlength(bs->file->bs);
+}
+
+/* This bh is used for synchronization of return from coroutines.
+ It continues yielded coroutine which then finishes its execution.
+ BH is called adjusted to some replay checkpoint, therefore
+ record and replay will always finish coroutines deterministically.
+*/
+static void blkreplay_bh_cb(void *opaque)
+{
+ Request *req = opaque;
+ qemu_coroutine_enter(req->co, NULL);
+ qemu_bh_delete(req->bh);
+ g_free(req);
+}
+
+static void block_request_create(uint64_t reqid, BlockDriverState *bs,
+ Coroutine *co)
+{
+ Request *req = g_new(Request, 1);
+ *req = (Request) {
+ .co = co,
+ .bh = aio_bh_new(bdrv_get_aio_context(bs), blkreplay_bh_cb, req),
+ };
+ replay_block_event(req->bh, reqid);
+}
+
+static int coroutine_fn blkreplay_co_readv(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
+{
+ uint64_t reqid = request_id++;
+ int ret = bdrv_co_readv(bs->file->bs, sector_num, nb_sectors, qiov);
+ block_request_create(reqid, bs, qemu_coroutine_self());
+ qemu_coroutine_yield();
+
+ return ret;
+}
+
+static int coroutine_fn blkreplay_co_writev(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
+{
+ uint64_t reqid = request_id++;
+ int ret = bdrv_co_writev(bs->file->bs, sector_num, nb_sectors, qiov);
+ block_request_create(reqid, bs, qemu_coroutine_self());
+ qemu_coroutine_yield();
+
+ return ret;
+}
+
+static int coroutine_fn blkreplay_co_write_zeroes(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors, BdrvRequestFlags flags)
+{
+ uint64_t reqid = request_id++;
+ int ret = bdrv_co_write_zeroes(bs->file->bs, sector_num, nb_sectors, flags);
+ block_request_create(reqid, bs, qemu_coroutine_self());
+ qemu_coroutine_yield();
+
+ return ret;
+}
+
+static int coroutine_fn blkreplay_co_discard(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors)
+{
+ uint64_t reqid = request_id++;
+ int ret = bdrv_co_discard(bs->file->bs, sector_num, nb_sectors);
+ block_request_create(reqid, bs, qemu_coroutine_self());
+ qemu_coroutine_yield();
+
+ return ret;
+}
+
+static int coroutine_fn blkreplay_co_flush(BlockDriverState *bs)
+{
+ uint64_t reqid = request_id++;
+ int ret = bdrv_co_flush(bs->file->bs);
+ block_request_create(reqid, bs, qemu_coroutine_self());
+ qemu_coroutine_yield();
+
+ return ret;
+}
+
+static BlockDriver bdrv_blkreplay = {
+ .format_name = "blkreplay",
+ .protocol_name = "blkreplay",
+ .instance_size = 0,
+
+ .bdrv_file_open = blkreplay_open,
+ .bdrv_close = blkreplay_close,
+ .bdrv_getlength = blkreplay_getlength,
+
+ .bdrv_co_readv = blkreplay_co_readv,
+ .bdrv_co_writev = blkreplay_co_writev,
+
+ .bdrv_co_write_zeroes = blkreplay_co_write_zeroes,
+ .bdrv_co_discard = blkreplay_co_discard,
+ .bdrv_co_flush = blkreplay_co_flush,
+};
+
+static void bdrv_blkreplay_init(void)
+{
+ bdrv_register(&bdrv_blkreplay);
+}
+
+block_init(bdrv_blkreplay_init);