Virtio-loopback-adapter Beta version for review:

- Beta version of the code to be discussed during the review planned on the 09/11/2022
- Before being merged into master, this code might be changed with fixes and optimization

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>

1 files changed, 95 insertions, 0 deletions

diff --git a/virtio_blk.h b/virtio_blk.h
new file mode 100644
index 0000000..75534ed
--- /dev/null
+++ b/virtio_blk.h
@@ -0,0 +1,95 @@
+/*
+ * Virtio Block Device
+ *
+ * Copyright IBM, Corp. 2007
+ *
+ * Authors:
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef QEMU_VIRTIO_BLK_H
+#define QEMU_VIRTIO_BLK_H
+
+#include "standard-headers/linux/virtio_blk.h"
+#include "hw/virtio/virtio.h"
+#include "hw/block/block.h"
+#include "sysemu/iothread.h"
+#include "sysemu/block-backend.h"
+#include "qom/object.h"
+
+#define TYPE_VIRTIO_BLK "virtio-blk-device"
+#define VIRTIO_BLK_AUTO_NUM_QUEUES UINT16_MAX
+OBJECT_DECLARE_SIMPLE_TYPE(VirtIOBlock, VIRTIO_BLK)
+
+/* This is the last element of the write scatter-gather list */
+struct virtio_blk_inhdr {
+    unsigned char status;
+};
+
+
+struct VirtIOBlkConf {
+    BlockConf conf;
+    IOThread *iothread;
+    char *serial;
+    uint32_t request_merging;
+    uint16_t num_queues;
+    uint16_t queue_size;
+    bool seg_max_adjust;
+    bool report_discard_granularity;
+    uint32_t max_discard_sectors;
+    uint32_t max_write_zeroes_sectors;
+    bool x_enable_wce_if_config_wce;
+};
+
+
+struct VirtIOBlockDataPlane;
+
+struct VirtIOBlockReq;
+struct VirtIOBlock {
+    VirtIODevice parent_obj;
+    BlockBackend *blk;
+    void *rq;
+    QEMUBH *bh;
+    VirtIOBlkConf conf;
+    unsigned short sector_mask;
+    bool original_wce;
+    VMChangeStateEntry *change;
+    bool dataplane_disabled;
+    bool dataplane_started;
+    struct VirtIOBlockDataPlane *dataplane;
+    uint64_t host_features;
+    size_t config_size;
+};
+
+typedef struct VirtIOBlockReq {
+    VirtQueueElement elem;
+    int64_t sector_num;
+    VirtIOBlock *dev;
+    VirtQueue *vq;
+    IOVDiscardUndo inhdr_undo;
+    IOVDiscardUndo outhdr_undo;
+    struct virtio_blk_inhdr *in;
+    struct virtio_blk_outhdr out;
+    QEMUIOVector qiov;
+    size_t in_len;
+    struct VirtIOBlockReq *next;
+    struct VirtIOBlockReq *mr_next;
+    BlockAcctCookie acct;
+} VirtIOBlockReq;
+
+#define VIRTIO_BLK_MAX_MERGE_REQS 32
+
+typedef struct MultiReqBuffer {
+    VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS];
+    unsigned int num_reqs;
+    bool is_write;
+} MultiReqBuffer;
+
+bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq);
+void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh);
+
+#endif