Adding qemu as a submodule of KVMFORNFV

This Patch includes the changes to add qemu as a submodule to
kvmfornfv repo and make use of the updated latest qemu for the
execution of all testcase
Change-Id: I1280af507a857675c7f81d30c95255635667bdd7
Signed-off-by:RajithaY<rajithax.yerrumsetty@intel.com>

1 files changed, 0 insertions, 3042 deletions

diff --git a/qemu/block/sheepdog.c b/qemu/block/sheepdog.c
deleted file mode 100644
index 33e0a3382..000000000
--- a/qemu/block/sheepdog.c
+++ /dev/null
@@ -1,3042 +0,0 @@
-/*
- * Copyright (C) 2009-2010 Nippon Telegraph and Telephone Corporation.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License version
- * 2 as published by the Free Software Foundation.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- *
- * Contributions after 2012-01-13 are licensed under the terms of the
- * GNU GPL, version 2 or (at your option) any later version.
- */
-
-#include "qemu/osdep.h"
-#include "qapi/error.h"
-#include "qemu/uri.h"
-#include "qemu/error-report.h"
-#include "qemu/sockets.h"
-#include "block/block_int.h"
-#include "sysemu/block-backend.h"
-#include "qemu/bitops.h"
-#include "qemu/cutils.h"
-
-#define SD_PROTO_VER 0x01
-
-#define SD_DEFAULT_ADDR "localhost"
-#define SD_DEFAULT_PORT 7000
-
-#define SD_OP_CREATE_AND_WRITE_OBJ  0x01
-#define SD_OP_READ_OBJ       0x02
-#define SD_OP_WRITE_OBJ      0x03
-/* 0x04 is used internally by Sheepdog */
-
-#define SD_OP_NEW_VDI        0x11
-#define SD_OP_LOCK_VDI       0x12
-#define SD_OP_RELEASE_VDI    0x13
-#define SD_OP_GET_VDI_INFO   0x14
-#define SD_OP_READ_VDIS      0x15
-#define SD_OP_FLUSH_VDI      0x16
-#define SD_OP_DEL_VDI        0x17
-#define SD_OP_GET_CLUSTER_DEFAULT   0x18
-
-#define SD_FLAG_CMD_WRITE    0x01
-#define SD_FLAG_CMD_COW      0x02
-#define SD_FLAG_CMD_CACHE    0x04 /* Writeback mode for cache */
-#define SD_FLAG_CMD_DIRECT   0x08 /* Don't use cache */
-
-#define SD_RES_SUCCESS       0x00 /* Success */
-#define SD_RES_UNKNOWN       0x01 /* Unknown error */
-#define SD_RES_NO_OBJ        0x02 /* No object found */
-#define SD_RES_EIO           0x03 /* I/O error */
-#define SD_RES_VDI_EXIST     0x04 /* Vdi exists already */
-#define SD_RES_INVALID_PARMS 0x05 /* Invalid parameters */
-#define SD_RES_SYSTEM_ERROR  0x06 /* System error */
-#define SD_RES_VDI_LOCKED    0x07 /* Vdi is locked */
-#define SD_RES_NO_VDI        0x08 /* No vdi found */
-#define SD_RES_NO_BASE_VDI   0x09 /* No base vdi found */
-#define SD_RES_VDI_READ      0x0A /* Cannot read requested vdi */
-#define SD_RES_VDI_WRITE     0x0B /* Cannot write requested vdi */
-#define SD_RES_BASE_VDI_READ 0x0C /* Cannot read base vdi */
-#define SD_RES_BASE_VDI_WRITE   0x0D /* Cannot write base vdi */
-#define SD_RES_NO_TAG        0x0E /* Requested tag is not found */
-#define SD_RES_STARTUP       0x0F /* Sheepdog is on starting up */
-#define SD_RES_VDI_NOT_LOCKED   0x10 /* Vdi is not locked */
-#define SD_RES_SHUTDOWN      0x11 /* Sheepdog is shutting down */
-#define SD_RES_NO_MEM        0x12 /* Cannot allocate memory */
-#define SD_RES_FULL_VDI      0x13 /* we already have the maximum vdis */
-#define SD_RES_VER_MISMATCH  0x14 /* Protocol version mismatch */
-#define SD_RES_NO_SPACE      0x15 /* Server has no room for new objects */
-#define SD_RES_WAIT_FOR_FORMAT  0x16 /* Waiting for a format operation */
-#define SD_RES_WAIT_FOR_JOIN    0x17 /* Waiting for other nodes joining */
-#define SD_RES_JOIN_FAILED   0x18 /* Target node had failed to join sheepdog */
-#define SD_RES_HALT          0x19 /* Sheepdog is stopped serving IO request */
-#define SD_RES_READONLY      0x1A /* Object is read-only */
-
-/*
- * Object ID rules
- *
- *  0 - 19 (20 bits): data object space
- * 20 - 31 (12 bits): reserved data object space
- * 32 - 55 (24 bits): vdi object space
- * 56 - 59 ( 4 bits): reserved vdi object space
- * 60 - 63 ( 4 bits): object type identifier space
- */
-
-#define VDI_SPACE_SHIFT   32
-#define VDI_BIT (UINT64_C(1) << 63)
-#define VMSTATE_BIT (UINT64_C(1) << 62)
-#define MAX_DATA_OBJS (UINT64_C(1) << 20)
-#define MAX_CHILDREN 1024
-#define SD_MAX_VDI_LEN 256
-#define SD_MAX_VDI_TAG_LEN 256
-#define SD_NR_VDIS   (1U << 24)
-#define SD_DATA_OBJ_SIZE (UINT64_C(1) << 22)
-#define SD_MAX_VDI_SIZE (SD_DATA_OBJ_SIZE * MAX_DATA_OBJS)
-#define SD_DEFAULT_BLOCK_SIZE_SHIFT 22
-/*
- * For erasure coding, we use at most SD_EC_MAX_STRIP for data strips and
- * (SD_EC_MAX_STRIP - 1) for parity strips
- *
- * SD_MAX_COPIES is sum of number of data strips and parity strips.
- */
-#define SD_EC_MAX_STRIP 16
-#define SD_MAX_COPIES (SD_EC_MAX_STRIP * 2 - 1)
-
-#define SD_INODE_SIZE (sizeof(SheepdogInode))
-#define CURRENT_VDI_ID 0
-
-#define LOCK_TYPE_NORMAL 0
-#define LOCK_TYPE_SHARED 1      /* for iSCSI multipath */
-
-typedef struct SheepdogReq {
-    uint8_t proto_ver;
-    uint8_t opcode;
-    uint16_t flags;
-    uint32_t epoch;
-    uint32_t id;
-    uint32_t data_length;
-    uint32_t opcode_specific[8];
-} SheepdogReq;
-
-typedef struct SheepdogRsp {
-    uint8_t proto_ver;
-    uint8_t opcode;
-    uint16_t flags;
-    uint32_t epoch;
-    uint32_t id;
-    uint32_t data_length;
-    uint32_t result;
-    uint32_t opcode_specific[7];
-} SheepdogRsp;
-
-typedef struct SheepdogObjReq {
-    uint8_t proto_ver;
-    uint8_t opcode;
-    uint16_t flags;
-    uint32_t epoch;
-    uint32_t id;
-    uint32_t data_length;
-    uint64_t oid;
-    uint64_t cow_oid;
-    uint8_t copies;
-    uint8_t copy_policy;
-    uint8_t reserved[6];
-    uint64_t offset;
-} SheepdogObjReq;
-
-typedef struct SheepdogObjRsp {
-    uint8_t proto_ver;
-    uint8_t opcode;
-    uint16_t flags;
-    uint32_t epoch;
-    uint32_t id;
-    uint32_t data_length;
-    uint32_t result;
-    uint8_t copies;
-    uint8_t copy_policy;
-    uint8_t reserved[2];
-    uint32_t pad[6];
-} SheepdogObjRsp;
-
-typedef struct SheepdogVdiReq {
-    uint8_t proto_ver;
-    uint8_t opcode;
-    uint16_t flags;
-    uint32_t epoch;
-    uint32_t id;
-    uint32_t data_length;
-    uint64_t vdi_size;
-    uint32_t base_vdi_id;
-    uint8_t copies;
-    uint8_t copy_policy;
-    uint8_t store_policy;
-    uint8_t block_size_shift;
-    uint32_t snapid;
-    uint32_t type;
-    uint32_t pad[2];
-} SheepdogVdiReq;
-
-typedef struct SheepdogVdiRsp {
-    uint8_t proto_ver;
-    uint8_t opcode;
-    uint16_t flags;
-    uint32_t epoch;
-    uint32_t id;
-    uint32_t data_length;
-    uint32_t result;
-    uint32_t rsvd;
-    uint32_t vdi_id;
-    uint32_t pad[5];
-} SheepdogVdiRsp;
-
-typedef struct SheepdogClusterRsp {
-    uint8_t proto_ver;
-    uint8_t opcode;
-    uint16_t flags;
-    uint32_t epoch;
-    uint32_t id;
-    uint32_t data_length;
-    uint32_t result;
-    uint8_t nr_copies;
-    uint8_t copy_policy;
-    uint8_t block_size_shift;
-    uint8_t __pad1;
-    uint32_t __pad2[6];
-} SheepdogClusterRsp;
-
-typedef struct SheepdogInode {
-    char name[SD_MAX_VDI_LEN];
-    char tag[SD_MAX_VDI_TAG_LEN];
-    uint64_t ctime;
-    uint64_t snap_ctime;
-    uint64_t vm_clock_nsec;
-    uint64_t vdi_size;
-    uint64_t vm_state_size;
-    uint16_t copy_policy;
-    uint8_t nr_copies;
-    uint8_t block_size_shift;
-    uint32_t snap_id;
-    uint32_t vdi_id;
-    uint32_t parent_vdi_id;
-    uint32_t child_vdi_id[MAX_CHILDREN];
-    uint32_t data_vdi_id[MAX_DATA_OBJS];
-} SheepdogInode;
-
-#define SD_INODE_HEADER_SIZE offsetof(SheepdogInode, data_vdi_id)
-
-/*
- * 64 bit FNV-1a non-zero initial basis
- */
-#define FNV1A_64_INIT ((uint64_t)0xcbf29ce484222325ULL)
-
-/*
- * 64 bit Fowler/Noll/Vo FNV-1a hash code
- */
-static inline uint64_t fnv_64a_buf(void *buf, size_t len, uint64_t hval)
-{
-    unsigned char *bp = buf;
-    unsigned char *be = bp + len;
-    while (bp < be) {
-        hval ^= (uint64_t) *bp++;
-        hval += (hval << 1) + (hval << 4) + (hval << 5) +
-            (hval << 7) + (hval << 8) + (hval << 40);
-    }
-    return hval;
-}
-
-static inline bool is_data_obj_writable(SheepdogInode *inode, unsigned int idx)
-{
-    return inode->vdi_id == inode->data_vdi_id[idx];
-}
-
-static inline bool is_data_obj(uint64_t oid)
-{
-    return !(VDI_BIT & oid);
-}
-
-static inline uint64_t data_oid_to_idx(uint64_t oid)
-{
-    return oid & (MAX_DATA_OBJS - 1);
-}
-
-static inline uint32_t oid_to_vid(uint64_t oid)
-{
-    return (oid & ~VDI_BIT) >> VDI_SPACE_SHIFT;
-}
-
-static inline uint64_t vid_to_vdi_oid(uint32_t vid)
-{
-    return VDI_BIT | ((uint64_t)vid << VDI_SPACE_SHIFT);
-}
-
-static inline uint64_t vid_to_vmstate_oid(uint32_t vid, uint32_t idx)
-{
-    return VMSTATE_BIT | ((uint64_t)vid << VDI_SPACE_SHIFT) | idx;
-}
-
-static inline uint64_t vid_to_data_oid(uint32_t vid, uint32_t idx)
-{
-    return ((uint64_t)vid << VDI_SPACE_SHIFT) | idx;
-}
-
-static inline bool is_snapshot(struct SheepdogInode *inode)
-{
-    return !!inode->snap_ctime;
-}
-
-static inline size_t count_data_objs(const struct SheepdogInode *inode)
-{
-    return DIV_ROUND_UP(inode->vdi_size,
-                        (1UL << inode->block_size_shift));
-}
-
-#undef DPRINTF
-#ifdef DEBUG_SDOG
-#define DPRINTF(fmt, args...)                                       \
-    do {                                                            \
-        fprintf(stdout, "%s %d: " fmt, __func__, __LINE__, ##args); \
-    } while (0)
-#else
-#define DPRINTF(fmt, args...)
-#endif
-
-typedef struct SheepdogAIOCB SheepdogAIOCB;
-
-typedef struct AIOReq {
-    SheepdogAIOCB *aiocb;
-    unsigned int iov_offset;
-
-    uint64_t oid;
-    uint64_t base_oid;
-    uint64_t offset;
-    unsigned int data_len;
-    uint8_t flags;
-    uint32_t id;
-    bool create;
-
-    QLIST_ENTRY(AIOReq) aio_siblings;
-} AIOReq;
-
-enum AIOCBState {
-    AIOCB_WRITE_UDATA,
-    AIOCB_READ_UDATA,
-    AIOCB_FLUSH_CACHE,
-    AIOCB_DISCARD_OBJ,
-};
-
-#define AIOCBOverlapping(x, y)                                 \
-    (!(x->max_affect_data_idx < y->min_affect_data_idx          \
-       || y->max_affect_data_idx < x->min_affect_data_idx))
-
-struct SheepdogAIOCB {
-    BlockAIOCB common;
-
-    QEMUIOVector *qiov;
-
-    int64_t sector_num;
-    int nb_sectors;
-
-    int ret;
-    enum AIOCBState aiocb_type;
-
-    Coroutine *coroutine;
-    void (*aio_done_func)(SheepdogAIOCB *);
-
-    bool cancelable;
-    int nr_pending;
-
-    uint32_t min_affect_data_idx;
-    uint32_t max_affect_data_idx;
-
-    /*
-     * The difference between affect_data_idx and dirty_data_idx:
-     * affect_data_idx represents range of index of all request types.
-     * dirty_data_idx represents range of index updated by COW requests.
-     * dirty_data_idx is used for updating an inode object.
-     */
-    uint32_t min_dirty_data_idx;
-    uint32_t max_dirty_data_idx;
-
-    QLIST_ENTRY(SheepdogAIOCB) aiocb_siblings;
-};
-
-typedef struct BDRVSheepdogState {
-    BlockDriverState *bs;
-    AioContext *aio_context;
-
-    SheepdogInode inode;
-
-    char name[SD_MAX_VDI_LEN];
-    bool is_snapshot;
-    uint32_t cache_flags;
-    bool discard_supported;
-
-    char *host_spec;
-    bool is_unix;
-    int fd;
-
-    CoMutex lock;
-    Coroutine *co_send;
-    Coroutine *co_recv;
-
-    uint32_t aioreq_seq_num;
-
-    /* Every aio request must be linked to either of these queues. */
-    QLIST_HEAD(inflight_aio_head, AIOReq) inflight_aio_head;
-    QLIST_HEAD(failed_aio_head, AIOReq) failed_aio_head;
-
-    CoQueue overlapping_queue;
-    QLIST_HEAD(inflight_aiocb_head, SheepdogAIOCB) inflight_aiocb_head;
-} BDRVSheepdogState;
-
-typedef struct BDRVSheepdogReopenState {
-    int fd;
-    int cache_flags;
-} BDRVSheepdogReopenState;
-
-static const char * sd_strerror(int err)
-{
-    int i;
-
-    static const struct {
-        int err;
-        const char *desc;
-    } errors[] = {
-        {SD_RES_SUCCESS, "Success"},
-        {SD_RES_UNKNOWN, "Unknown error"},
-        {SD_RES_NO_OBJ, "No object found"},
-        {SD_RES_EIO, "I/O error"},
-        {SD_RES_VDI_EXIST, "VDI exists already"},
-        {SD_RES_INVALID_PARMS, "Invalid parameters"},
-        {SD_RES_SYSTEM_ERROR, "System error"},
-        {SD_RES_VDI_LOCKED, "VDI is already locked"},
-        {SD_RES_NO_VDI, "No vdi found"},
-        {SD_RES_NO_BASE_VDI, "No base VDI found"},
-        {SD_RES_VDI_READ, "Failed read the requested VDI"},
-        {SD_RES_VDI_WRITE, "Failed to write the requested VDI"},
-        {SD_RES_BASE_VDI_READ, "Failed to read the base VDI"},
-        {SD_RES_BASE_VDI_WRITE, "Failed to write the base VDI"},
-        {SD_RES_NO_TAG, "Failed to find the requested tag"},
-        {SD_RES_STARTUP, "The system is still booting"},
-        {SD_RES_VDI_NOT_LOCKED, "VDI isn't locked"},
-        {SD_RES_SHUTDOWN, "The system is shutting down"},
-        {SD_RES_NO_MEM, "Out of memory on the server"},
-        {SD_RES_FULL_VDI, "We already have the maximum vdis"},
-        {SD_RES_VER_MISMATCH, "Protocol version mismatch"},
-        {SD_RES_NO_SPACE, "Server has no space for new objects"},
-        {SD_RES_WAIT_FOR_FORMAT, "Sheepdog is waiting for a format operation"},
-        {SD_RES_WAIT_FOR_JOIN, "Sheepdog is waiting for other nodes joining"},
-        {SD_RES_JOIN_FAILED, "Target node had failed to join sheepdog"},
-        {SD_RES_HALT, "Sheepdog is stopped serving IO request"},
-        {SD_RES_READONLY, "Object is read-only"},
-    };
-
-    for (i = 0; i < ARRAY_SIZE(errors); ++i) {
-        if (errors[i].err == err) {
-            return errors[i].desc;
-        }
-    }
-
-    return "Invalid error code";
-}
-
-/*
- * Sheepdog I/O handling:
- *
- * 1. In sd_co_rw_vector, we send the I/O requests to the server and
- *    link the requests to the inflight_list in the
- *    BDRVSheepdogState.  The function exits without waiting for
- *    receiving the response.
- *
- * 2. We receive the response in aio_read_response, the fd handler to
- *    the sheepdog connection.  If metadata update is needed, we send
- *    the write request to the vdi object in sd_write_done, the write
- *    completion function.  We switch back to sd_co_readv/writev after
- *    all the requests belonging to the AIOCB are finished.
- */
-
-static inline AIOReq *alloc_aio_req(BDRVSheepdogState *s, SheepdogAIOCB *acb,
-                                    uint64_t oid, unsigned int data_len,
-                                    uint64_t offset, uint8_t flags, bool create,
-                                    uint64_t base_oid, unsigned int iov_offset)
-{
-    AIOReq *aio_req;
-
-    aio_req = g_malloc(sizeof(*aio_req));
-    aio_req->aiocb = acb;
-    aio_req->iov_offset = iov_offset;
-    aio_req->oid = oid;
-    aio_req->base_oid = base_oid;
-    aio_req->offset = offset;
-    aio_req->data_len = data_len;
-    aio_req->flags = flags;
-    aio_req->id = s->aioreq_seq_num++;
-    aio_req->create = create;
-
-    acb->nr_pending++;
-    return aio_req;
-}
-
-static inline void free_aio_req(BDRVSheepdogState *s, AIOReq *aio_req)
-{
-    SheepdogAIOCB *acb = aio_req->aiocb;
-
-    acb->cancelable = false;
-    QLIST_REMOVE(aio_req, aio_siblings);
-    g_free(aio_req);
-
-    acb->nr_pending--;
-}
-
-static void coroutine_fn sd_finish_aiocb(SheepdogAIOCB *acb)
-{
-    qemu_coroutine_enter(acb->coroutine, NULL);
-    qemu_aio_unref(acb);
-}
-
-/*
- * Check whether the specified acb can be canceled
- *
- * We can cancel aio when any request belonging to the acb is:
- *  - Not processed by the sheepdog server.
- *  - Not linked to the inflight queue.
- */
-static bool sd_acb_cancelable(const SheepdogAIOCB *acb)
-{
-    BDRVSheepdogState *s = acb->common.bs->opaque;
-    AIOReq *aioreq;
-
-    if (!acb->cancelable) {
-        return false;
-    }
-
-    QLIST_FOREACH(aioreq, &s->inflight_aio_head, aio_siblings) {
-        if (aioreq->aiocb == acb) {
-            return false;
-        }
-    }
-
-    return true;
-}
-
-static void sd_aio_cancel(BlockAIOCB *blockacb)
-{
-    SheepdogAIOCB *acb = (SheepdogAIOCB *)blockacb;
-    BDRVSheepdogState *s = acb->common.bs->opaque;
-    AIOReq *aioreq, *next;
-
-    if (sd_acb_cancelable(acb)) {
-        /* Remove outstanding requests from failed queue.  */
-        QLIST_FOREACH_SAFE(aioreq, &s->failed_aio_head, aio_siblings,
-                           next) {
-            if (aioreq->aiocb == acb) {
-                free_aio_req(s, aioreq);
-            }
-        }
-
-        assert(acb->nr_pending == 0);
-        if (acb->common.cb) {
-            acb->common.cb(acb->common.opaque, -ECANCELED);
-        }
-        sd_finish_aiocb(acb);
-    }
-}
-
-static const AIOCBInfo sd_aiocb_info = {
-    .aiocb_size     = sizeof(SheepdogAIOCB),
-    .cancel_async   = sd_aio_cancel,
-};
-
-static SheepdogAIOCB *sd_aio_setup(BlockDriverState *bs, QEMUIOVector *qiov,
-                                   int64_t sector_num, int nb_sectors)
-{
-    SheepdogAIOCB *acb;
-    uint32_t object_size;
-    BDRVSheepdogState *s = bs->opaque;
-
-    object_size = (UINT32_C(1) << s->inode.block_size_shift);
-
-    acb = qemu_aio_get(&sd_aiocb_info, bs, NULL, NULL);
-
-    acb->qiov = qiov;
-
-    acb->sector_num = sector_num;
-    acb->nb_sectors = nb_sectors;
-
-    acb->aio_done_func = NULL;
-    acb->cancelable = true;
-    acb->coroutine = qemu_coroutine_self();
-    acb->ret = 0;
-    acb->nr_pending = 0;
-
-    acb->min_affect_data_idx = acb->sector_num * BDRV_SECTOR_SIZE / object_size;
-    acb->max_affect_data_idx = (acb->sector_num * BDRV_SECTOR_SIZE +
-                              acb->nb_sectors * BDRV_SECTOR_SIZE) / object_size;
-
-    acb->min_dirty_data_idx = UINT32_MAX;
-    acb->max_dirty_data_idx = 0;
-
-    return acb;
-}
-
-/* Return -EIO in case of error, file descriptor on success */
-static int connect_to_sdog(BDRVSheepdogState *s, Error **errp)
-{
-    int fd;
-
-    if (s->is_unix) {
-        fd = unix_connect(s->host_spec, errp);
-    } else {
-        fd = inet_connect(s->host_spec, errp);
-
-        if (fd >= 0) {
-            int ret = socket_set_nodelay(fd);
-            if (ret < 0) {
-                error_report("%s", strerror(errno));
-            }
-        }
-    }
-
-    if (fd >= 0) {
-        qemu_set_nonblock(fd);
-    } else {
-        fd = -EIO;
-    }
-
-    return fd;
-}
-
-/* Return 0 on success and -errno in case of error */
-static coroutine_fn int send_co_req(int sockfd, SheepdogReq *hdr, void *data,
-                                    unsigned int *wlen)
-{
-    int ret;
-
-    ret = qemu_co_send(sockfd, hdr, sizeof(*hdr));
-    if (ret != sizeof(*hdr)) {
-        error_report("failed to send a req, %s", strerror(errno));
-        return -errno;
-    }
-
-    ret = qemu_co_send(sockfd, data, *wlen);
-    if (ret != *wlen) {
-        error_report("failed to send a req, %s", strerror(errno));
-        return -errno;
-    }
-
-    return ret;
-}
-
-static void restart_co_req(void *opaque)
-{
-    Coroutine *co = opaque;
-
-    qemu_coroutine_enter(co, NULL);
-}
-
-typedef struct SheepdogReqCo {
-    int sockfd;
-    AioContext *aio_context;
-    SheepdogReq *hdr;
-    void *data;
-    unsigned int *wlen;
-    unsigned int *rlen;
-    int ret;
-    bool finished;
-} SheepdogReqCo;
-
-static coroutine_fn void do_co_req(void *opaque)
-{
-    int ret;
-    Coroutine *co;
-    SheepdogReqCo *srco = opaque;
-    int sockfd = srco->sockfd;
-    SheepdogReq *hdr = srco->hdr;
-    void *data = srco->data;
-    unsigned int *wlen = srco->wlen;
-    unsigned int *rlen = srco->rlen;
-
-    co = qemu_coroutine_self();
-    aio_set_fd_handler(srco->aio_context, sockfd, false,
-                       NULL, restart_co_req, co);
-
-    ret = send_co_req(sockfd, hdr, data, wlen);
-    if (ret < 0) {
-        goto out;
-    }
-
-    aio_set_fd_handler(srco->aio_context, sockfd, false,
-                       restart_co_req, NULL, co);
-
-    ret = qemu_co_recv(sockfd, hdr, sizeof(*hdr));
-    if (ret != sizeof(*hdr)) {
-        error_report("failed to get a rsp, %s", strerror(errno));
-        ret = -errno;
-        goto out;
-    }
-
-    if (*rlen > hdr->data_length) {
-        *rlen = hdr->data_length;
-    }
-
-    if (*rlen) {
-        ret = qemu_co_recv(sockfd, data, *rlen);
-        if (ret != *rlen) {
-            error_report("failed to get the data, %s", strerror(errno));
-            ret = -errno;
-            goto out;
-        }
-    }
-    ret = 0;
-out:
-    /* there is at most one request for this sockfd, so it is safe to
-     * set each handler to NULL. */
-    aio_set_fd_handler(srco->aio_context, sockfd, false,
-                       NULL, NULL, NULL);
-
-    srco->ret = ret;
-    srco->finished = true;
-}
-
-/*
- * Send the request to the sheep in a synchronous manner.
- *
- * Return 0 on success, -errno in case of error.
- */
-static int do_req(int sockfd, AioContext *aio_context, SheepdogReq *hdr,
-                  void *data, unsigned int *wlen, unsigned int *rlen)
-{
-    Coroutine *co;
-    SheepdogReqCo srco = {
-        .sockfd = sockfd,
-        .aio_context = aio_context,
-        .hdr = hdr,
-        .data = data,
-        .wlen = wlen,
-        .rlen = rlen,
-        .ret = 0,
-        .finished = false,
-    };
-
-    if (qemu_in_coroutine()) {
-        do_co_req(&srco);
-    } else {
-        co = qemu_coroutine_create(do_co_req);
-        qemu_coroutine_enter(co, &srco);
-        while (!srco.finished) {
-            aio_poll(aio_context, true);
-        }
-    }
-
-    return srco.ret;
-}
-
-static void coroutine_fn add_aio_request(BDRVSheepdogState *s, AIOReq *aio_req,
-                                         struct iovec *iov, int niov,
-                                         enum AIOCBState aiocb_type);
-static void coroutine_fn resend_aioreq(BDRVSheepdogState *s, AIOReq *aio_req);
-static int reload_inode(BDRVSheepdogState *s, uint32_t snapid, const char *tag);
-static int get_sheep_fd(BDRVSheepdogState *s, Error **errp);
-static void co_write_request(void *opaque);
-
-static coroutine_fn void reconnect_to_sdog(void *opaque)
-{
-    BDRVSheepdogState *s = opaque;
-    AIOReq *aio_req, *next;
-
-    aio_set_fd_handler(s->aio_context, s->fd, false, NULL,
-                       NULL, NULL);
-    close(s->fd);
-    s->fd = -1;
-
-    /* Wait for outstanding write requests to be completed. */
-    while (s->co_send != NULL) {
-        co_write_request(opaque);
-    }
-
-    /* Try to reconnect the sheepdog server every one second. */
-    while (s->fd < 0) {
-        Error *local_err = NULL;
-        s->fd = get_sheep_fd(s, &local_err);
-        if (s->fd < 0) {
-            DPRINTF("Wait for connection to be established\n");
-            error_report_err(local_err);
-            co_aio_sleep_ns(bdrv_get_aio_context(s->bs), QEMU_CLOCK_REALTIME,
-                            1000000000ULL);
-        }
-    };
-
-    /*
-     * Now we have to resend all the request in the inflight queue.  However,
-     * resend_aioreq() can yield and newly created requests can be added to the
-     * inflight queue before the coroutine is resumed.  To avoid mixing them, we
-     * have to move all the inflight requests to the failed queue before
-     * resend_aioreq() is called.
-     */
-    QLIST_FOREACH_SAFE(aio_req, &s->inflight_aio_head, aio_siblings, next) {
-        QLIST_REMOVE(aio_req, aio_siblings);
-        QLIST_INSERT_HEAD(&s->failed_aio_head, aio_req, aio_siblings);
-    }
-
-    /* Resend all the failed aio requests. */
-    while (!QLIST_EMPTY(&s->failed_aio_head)) {
-        aio_req = QLIST_FIRST(&s->failed_aio_head);
-        QLIST_REMOVE(aio_req, aio_siblings);
-        QLIST_INSERT_HEAD(&s->inflight_aio_head, aio_req, aio_siblings);
-        resend_aioreq(s, aio_req);
-    }
-}
-
-/*
- * Receive responses of the I/O requests.
- *
- * This function is registered as a fd handler, and called from the
- * main loop when s->fd is ready for reading responses.
- */
-static void coroutine_fn aio_read_response(void *opaque)
-{
-    SheepdogObjRsp rsp;
-    BDRVSheepdogState *s = opaque;
-    int fd = s->fd;
-    int ret;
-    AIOReq *aio_req = NULL;
-    SheepdogAIOCB *acb;
-    uint64_t idx;
-
-    /* read a header */
-    ret = qemu_co_recv(fd, &rsp, sizeof(rsp));
-    if (ret != sizeof(rsp)) {
-        error_report("failed to get the header, %s", strerror(errno));
-        goto err;
-    }
-
-    /* find the right aio_req from the inflight aio list */
-    QLIST_FOREACH(aio_req, &s->inflight_aio_head, aio_siblings) {
-        if (aio_req->id == rsp.id) {
-            break;
-        }
-    }
-    if (!aio_req) {
-        error_report("cannot find aio_req %x", rsp.id);
-        goto err;
-    }
-
-    acb = aio_req->aiocb;
-
-    switch (acb->aiocb_type) {
-    case AIOCB_WRITE_UDATA:
-        /* this coroutine context is no longer suitable for co_recv
-         * because we may send data to update vdi objects */
-        s->co_recv = NULL;
-        if (!is_data_obj(aio_req->oid)) {
-            break;
-        }
-        idx = data_oid_to_idx(aio_req->oid);
-
-        if (aio_req->create) {
-            /*
-             * If the object is newly created one, we need to update
-             * the vdi object (metadata object).  min_dirty_data_idx
-             * and max_dirty_data_idx are changed to include updated
-             * index between them.
-             */
-            if (rsp.result == SD_RES_SUCCESS) {
-                s->inode.data_vdi_id[idx] = s->inode.vdi_id;
-                acb->max_dirty_data_idx = MAX(idx, acb->max_dirty_data_idx);
-                acb->min_dirty_data_idx = MIN(idx, acb->min_dirty_data_idx);
-            }
-        }
-        break;
-    case AIOCB_READ_UDATA:
-        ret = qemu_co_recvv(fd, acb->qiov->iov, acb->qiov->niov,
-                            aio_req->iov_offset, rsp.data_length);
-        if (ret != rsp.data_length) {
-            error_report("failed to get the data, %s", strerror(errno));
-            goto err;
-        }
-        break;
-    case AIOCB_FLUSH_CACHE:
-        if (rsp.result == SD_RES_INVALID_PARMS) {
-            DPRINTF("disable cache since the server doesn't support it\n");
-            s->cache_flags = SD_FLAG_CMD_DIRECT;
-            rsp.result = SD_RES_SUCCESS;
-        }
-        break;
-    case AIOCB_DISCARD_OBJ:
-        switch (rsp.result) {
-        case SD_RES_INVALID_PARMS:
-            error_report("sheep(%s) doesn't support discard command",
-                         s->host_spec);
-            rsp.result = SD_RES_SUCCESS;
-            s->discard_supported = false;
-            break;
-        default:
-            break;
-        }
-    }
-
-    switch (rsp.result) {
-    case SD_RES_SUCCESS:
-        break;
-    case SD_RES_READONLY:
-        if (s->inode.vdi_id == oid_to_vid(aio_req->oid)) {
-            ret = reload_inode(s, 0, "");
-            if (ret < 0) {
-                goto err;
-            }
-        }
-        if (is_data_obj(aio_req->oid)) {
-            aio_req->oid = vid_to_data_oid(s->inode.vdi_id,
-                                           data_oid_to_idx(aio_req->oid));
-        } else {
-            aio_req->oid = vid_to_vdi_oid(s->inode.vdi_id);
-        }
-        resend_aioreq(s, aio_req);
-        goto out;
-    default:
-        acb->ret = -EIO;
-        error_report("%s", sd_strerror(rsp.result));
-        break;
-    }
-
-    free_aio_req(s, aio_req);
-    if (!acb->nr_pending) {
-        /*
-         * We've finished all requests which belong to the AIOCB, so
-         * we can switch back to sd_co_readv/writev now.
-         */
-        acb->aio_done_func(acb);
-    }
-out:
-    s->co_recv = NULL;
-    return;
-err:
-    s->co_recv = NULL;
-    reconnect_to_sdog(opaque);
-}
-
-static void co_read_response(void *opaque)
-{
-    BDRVSheepdogState *s = opaque;
-
-    if (!s->co_recv) {
-        s->co_recv = qemu_coroutine_create(aio_read_response);
-    }
-
-    qemu_coroutine_enter(s->co_recv, opaque);
-}
-
-static void co_write_request(void *opaque)
-{
-    BDRVSheepdogState *s = opaque;
-
-    qemu_coroutine_enter(s->co_send, NULL);
-}
-
-/*
- * Return a socket descriptor to read/write objects.
- *
- * We cannot use this descriptor for other operations because
- * the block driver may be on waiting response from the server.
- */
-static int get_sheep_fd(BDRVSheepdogState *s, Error **errp)
-{
-    int fd;
-
-    fd = connect_to_sdog(s, errp);
-    if (fd < 0) {
-        return fd;
-    }
-
-    aio_set_fd_handler(s->aio_context, fd, false,
-                       co_read_response, NULL, s);
-    return fd;
-}
-
-static int sd_parse_uri(BDRVSheepdogState *s, const char *filename,
-                        char *vdi, uint32_t *snapid, char *tag)
-{
-    URI *uri;
-    QueryParams *qp = NULL;
-    int ret = 0;
-
-    uri = uri_parse(filename);
-    if (!uri) {
-        return -EINVAL;
-    }
-
-    /* transport */
-    if (!strcmp(uri->scheme, "sheepdog")) {
-        s->is_unix = false;
-    } else if (!strcmp(uri->scheme, "sheepdog+tcp")) {
-        s->is_unix = false;
-    } else if (!strcmp(uri->scheme, "sheepdog+unix")) {
-        s->is_unix = true;
-    } else {
-        ret = -EINVAL;
-        goto out;
-    }
-
-    if (uri->path == NULL || !strcmp(uri->path, "/")) {
-        ret = -EINVAL;
-        goto out;
-    }
-    pstrcpy(vdi, SD_MAX_VDI_LEN, uri->path + 1);
-
-    qp = query_params_parse(uri->query);
-    if (qp->n > 1 || (s->is_unix && !qp->n) || (!s->is_unix && qp->n)) {
-        ret = -EINVAL;
-        goto out;
-    }
-
-    if (s->is_unix) {
-        /* sheepdog+unix:///vdiname?socket=path */
-        if (uri->server || uri->port || strcmp(qp->p[0].name, "socket")) {
-            ret = -EINVAL;
-            goto out;
-        }
-        s->host_spec = g_strdup(qp->p[0].value);
-    } else {
-        /* sheepdog[+tcp]://[host:port]/vdiname */
-        s->host_spec = g_strdup_printf("%s:%d", uri->server ?: SD_DEFAULT_ADDR,
-                                       uri->port ?: SD_DEFAULT_PORT);
-    }
-
-    /* snapshot tag */
-    if (uri->fragment) {
-        *snapid = strtoul(uri->fragment, NULL, 10);
-        if (*snapid == 0) {
-            pstrcpy(tag, SD_MAX_VDI_TAG_LEN, uri->fragment);
-        }
-    } else {
-        *snapid = CURRENT_VDI_ID; /* search current vdi */
-    }
-
-out:
-    if (qp) {
-        query_params_free(qp);
-    }
-    uri_free(uri);
-    return ret;
-}
-
-/*
- * Parse a filename (old syntax)
- *
- * filename must be one of the following formats:
- *   1. [vdiname]
- *   2. [vdiname]:[snapid]
- *   3. [vdiname]:[tag]
- *   4. [hostname]:[port]:[vdiname]
- *   5. [hostname]:[port]:[vdiname]:[snapid]
- *   6. [hostname]:[port]:[vdiname]:[tag]
- *
- * You can boot from the snapshot images by specifying `snapid` or
- * `tag'.
- *
- * You can run VMs outside the Sheepdog cluster by specifying
- * `hostname' and `port' (experimental).
- */
-static int parse_vdiname(BDRVSheepdogState *s, const char *filename,
-                         char *vdi, uint32_t *snapid, char *tag)
-{
-    char *p, *q, *uri;
-    const char *host_spec, *vdi_spec;
-    int nr_sep, ret;
-
-    strstart(filename, "sheepdog:", (const char **)&filename);
-    p = q = g_strdup(filename);
-
-    /* count the number of separators */
-    nr_sep = 0;
-    while (*p) {
-        if (*p == ':') {
-            nr_sep++;
-        }
-        p++;
-    }
-    p = q;
-
-    /* use the first two tokens as host_spec. */
-    if (nr_sep >= 2) {
-        host_spec = p;
-        p = strchr(p, ':');
-        p++;
-        p = strchr(p, ':');
-        *p++ = '\0';
-    } else {
-        host_spec = "";
-    }
-
-    vdi_spec = p;
-
-    p = strchr(vdi_spec, ':');
-    if (p) {
-        *p++ = '#';
-    }
-
-    uri = g_strdup_printf("sheepdog://%s/%s", host_spec, vdi_spec);
-
-    ret = sd_parse_uri(s, uri, vdi, snapid, tag);
-
-    g_free(q);
-    g_free(uri);
-
-    return ret;
-}
-
-static int find_vdi_name(BDRVSheepdogState *s, const char *filename,
-                         uint32_t snapid, const char *tag, uint32_t *vid,
-                         bool lock, Error **errp)
-{
-    int ret, fd;
-    SheepdogVdiReq hdr;
-    SheepdogVdiRsp *rsp = (SheepdogVdiRsp *)&hdr;
-    unsigned int wlen, rlen = 0;
-    char buf[SD_MAX_VDI_LEN + SD_MAX_VDI_TAG_LEN];
-
-    fd = connect_to_sdog(s, errp);
-    if (fd < 0) {
-        return fd;
-    }
-
-    /* This pair of strncpy calls ensures that the buffer is zero-filled,
-     * which is desirable since we'll soon be sending those bytes, and
-     * don't want the send_req to read uninitialized data.
-     */
-    strncpy(buf, filename, SD_MAX_VDI_LEN);
-    strncpy(buf + SD_MAX_VDI_LEN, tag, SD_MAX_VDI_TAG_LEN);
-
-    memset(&hdr, 0, sizeof(hdr));
-    if (lock) {
-        hdr.opcode = SD_OP_LOCK_VDI;
-        hdr.type = LOCK_TYPE_NORMAL;
-    } else {
-        hdr.opcode = SD_OP_GET_VDI_INFO;
-    }
-    wlen = SD_MAX_VDI_LEN + SD_MAX_VDI_TAG_LEN;
-    hdr.proto_ver = SD_PROTO_VER;
-    hdr.data_length = wlen;
-    hdr.snapid = snapid;
-    hdr.flags = SD_FLAG_CMD_WRITE;
-
-    ret = do_req(fd, s->aio_context, (SheepdogReq *)&hdr, buf, &wlen, &rlen);
-    if (ret) {
-        error_setg_errno(errp, -ret, "cannot get vdi info");
-        goto out;
-    }
-
-    if (rsp->result != SD_RES_SUCCESS) {
-        error_setg(errp, "cannot get vdi info, %s, %s %" PRIu32 " %s",
-                   sd_strerror(rsp->result), filename, snapid, tag);
-        if (rsp->result == SD_RES_NO_VDI) {
-            ret = -ENOENT;
-        } else if (rsp->result == SD_RES_VDI_LOCKED) {
-            ret = -EBUSY;
-        } else {
-            ret = -EIO;
-        }
-        goto out;
-    }
-    *vid = rsp->vdi_id;
-
-    ret = 0;
-out:
-    closesocket(fd);
-    return ret;
-}
-
-static void coroutine_fn add_aio_request(BDRVSheepdogState *s, AIOReq *aio_req,
-                                         struct iovec *iov, int niov,
-                                         enum AIOCBState aiocb_type)
-{
-    int nr_copies = s->inode.nr_copies;
-    SheepdogObjReq hdr;
-    unsigned int wlen = 0;
-    int ret;
-    uint64_t oid = aio_req->oid;
-    unsigned int datalen = aio_req->data_len;
-    uint64_t offset = aio_req->offset;
-    uint8_t flags = aio_req->flags;
-    uint64_t old_oid = aio_req->base_oid;
-    bool create = aio_req->create;
-
-    if (!nr_copies) {
-        error_report("bug");
-    }
-
-    memset(&hdr, 0, sizeof(hdr));
-
-    switch (aiocb_type) {
-    case AIOCB_FLUSH_CACHE:
-        hdr.opcode = SD_OP_FLUSH_VDI;
-        break;
-    case AIOCB_READ_UDATA:
-        hdr.opcode = SD_OP_READ_OBJ;
-        hdr.flags = flags;
-        break;
-    case AIOCB_WRITE_UDATA:
-        if (create) {
-            hdr.opcode = SD_OP_CREATE_AND_WRITE_OBJ;
-        } else {
-            hdr.opcode = SD_OP_WRITE_OBJ;
-        }
-        wlen = datalen;
-        hdr.flags = SD_FLAG_CMD_WRITE | flags;
-        break;
-    case AIOCB_DISCARD_OBJ:
-        hdr.opcode = SD_OP_WRITE_OBJ;
-        hdr.flags = SD_FLAG_CMD_WRITE | flags;
-        s->inode.data_vdi_id[data_oid_to_idx(oid)] = 0;
-        offset = offsetof(SheepdogInode,
-                          data_vdi_id[data_oid_to_idx(oid)]);
-        oid = vid_to_vdi_oid(s->inode.vdi_id);
-        wlen = datalen = sizeof(uint32_t);
-        break;
-    }
-
-    if (s->cache_flags) {
-        hdr.flags |= s->cache_flags;
-    }
-
-    hdr.oid = oid;
-    hdr.cow_oid = old_oid;
-    hdr.copies = s->inode.nr_copies;
-
-    hdr.data_length = datalen;
-    hdr.offset = offset;
-
-    hdr.id = aio_req->id;
-
-    qemu_co_mutex_lock(&s->lock);
-    s->co_send = qemu_coroutine_self();
-    aio_set_fd_handler(s->aio_context, s->fd, false,
-                       co_read_response, co_write_request, s);
-    socket_set_cork(s->fd, 1);
-
-    /* send a header */
-    ret = qemu_co_send(s->fd, &hdr, sizeof(hdr));
-    if (ret != sizeof(hdr)) {
-        error_report("failed to send a req, %s", strerror(errno));
-        goto out;
-    }
-
-    if (wlen) {
-        ret = qemu_co_sendv(s->fd, iov, niov, aio_req->iov_offset, wlen);
-        if (ret != wlen) {
-            error_report("failed to send a data, %s", strerror(errno));
-        }
-    }
-out:
-    socket_set_cork(s->fd, 0);
-    aio_set_fd_handler(s->aio_context, s->fd, false,
-                       co_read_response, NULL, s);
-    s->co_send = NULL;
-    qemu_co_mutex_unlock(&s->lock);
-}
-
-static int read_write_object(int fd, AioContext *aio_context, char *buf,
-                             uint64_t oid, uint8_t copies,
-                             unsigned int datalen, uint64_t offset,
-                             bool write, bool create, uint32_t cache_flags)
-{
-    SheepdogObjReq hdr;
-    SheepdogObjRsp *rsp = (SheepdogObjRsp *)&hdr;
-    unsigned int wlen, rlen;
-    int ret;
-
-    memset(&hdr, 0, sizeof(hdr));
-
-    if (write) {
-        wlen = datalen;
-        rlen = 0;
-        hdr.flags = SD_FLAG_CMD_WRITE;
-        if (create) {
-            hdr.opcode = SD_OP_CREATE_AND_WRITE_OBJ;
-        } else {
-            hdr.opcode = SD_OP_WRITE_OBJ;
-        }
-    } else {
-        wlen = 0;
-        rlen = datalen;
-        hdr.opcode = SD_OP_READ_OBJ;
-    }
-
-    hdr.flags |= cache_flags;
-
-    hdr.oid = oid;
-    hdr.data_length = datalen;
-    hdr.offset = offset;
-    hdr.copies = copies;
-
-    ret = do_req(fd, aio_context, (SheepdogReq *)&hdr, buf, &wlen, &rlen);
-    if (ret) {
-        error_report("failed to send a request to the sheep");
-        return ret;
-    }
-
-    switch (rsp->result) {
-    case SD_RES_SUCCESS:
-        return 0;
-    default:
-        error_report("%s", sd_strerror(rsp->result));
-        return -EIO;
-    }
-}
-
-static int read_object(int fd, AioContext *aio_context, char *buf,
-                       uint64_t oid, uint8_t copies,
-                       unsigned int datalen, uint64_t offset,
-                       uint32_t cache_flags)
-{
-    return read_write_object(fd, aio_context, buf, oid, copies,
-                             datalen, offset, false,
-                             false, cache_flags);
-}
-
-static int write_object(int fd, AioContext *aio_context, char *buf,
-                        uint64_t oid, uint8_t copies,
-                        unsigned int datalen, uint64_t offset, bool create,
-                        uint32_t cache_flags)
-{
-    return read_write_object(fd, aio_context, buf, oid, copies,
-                             datalen, offset, true,
-                             create, cache_flags);
-}
-
-/* update inode with the latest state */
-static int reload_inode(BDRVSheepdogState *s, uint32_t snapid, const char *tag)
-{
-    Error *local_err = NULL;
-    SheepdogInode *inode;
-    int ret = 0, fd;
-    uint32_t vid = 0;
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        return -EIO;
-    }
-
-    inode = g_malloc(SD_INODE_HEADER_SIZE);
-
-    ret = find_vdi_name(s, s->name, snapid, tag, &vid, false, &local_err);
-    if (ret) {
-        error_report_err(local_err);
-        goto out;
-    }
-
-    ret = read_object(fd, s->aio_context, (char *)inode, vid_to_vdi_oid(vid),
-                      s->inode.nr_copies, SD_INODE_HEADER_SIZE, 0,
-                      s->cache_flags);
-    if (ret < 0) {
-        goto out;
-    }
-
-    if (inode->vdi_id != s->inode.vdi_id) {
-        memcpy(&s->inode, inode, SD_INODE_HEADER_SIZE);
-    }
-
-out:
-    g_free(inode);
-    closesocket(fd);
-
-    return ret;
-}
-
-static void coroutine_fn resend_aioreq(BDRVSheepdogState *s, AIOReq *aio_req)
-{
-    SheepdogAIOCB *acb = aio_req->aiocb;
-
-    aio_req->create = false;
-
-    /* check whether this request becomes a CoW one */
-    if (acb->aiocb_type == AIOCB_WRITE_UDATA && is_data_obj(aio_req->oid)) {
-        int idx = data_oid_to_idx(aio_req->oid);
-
-        if (is_data_obj_writable(&s->inode, idx)) {
-            goto out;
-        }
-
-        if (s->inode.data_vdi_id[idx]) {
-            aio_req->base_oid = vid_to_data_oid(s->inode.data_vdi_id[idx], idx);
-            aio_req->flags |= SD_FLAG_CMD_COW;
-        }
-        aio_req->create = true;
-    }
-out:
-    if (is_data_obj(aio_req->oid)) {
-        add_aio_request(s, aio_req, acb->qiov->iov, acb->qiov->niov,
-                        acb->aiocb_type);
-    } else {
-        struct iovec iov;
-        iov.iov_base = &s->inode;
-        iov.iov_len = sizeof(s->inode);
-        add_aio_request(s, aio_req, &iov, 1, AIOCB_WRITE_UDATA);
-    }
-}
-
-static void sd_detach_aio_context(BlockDriverState *bs)
-{
-    BDRVSheepdogState *s = bs->opaque;
-
-    aio_set_fd_handler(s->aio_context, s->fd, false, NULL,
-                       NULL, NULL);
-}
-
-static void sd_attach_aio_context(BlockDriverState *bs,
-                                  AioContext *new_context)
-{
-    BDRVSheepdogState *s = bs->opaque;
-
-    s->aio_context = new_context;
-    aio_set_fd_handler(new_context, s->fd, false,
-                       co_read_response, NULL, s);
-}
-
-/* TODO Convert to fine grained options */
-static QemuOptsList runtime_opts = {
-    .name = "sheepdog",
-    .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
-    .desc = {
-        {
-            .name = "filename",
-            .type = QEMU_OPT_STRING,
-            .help = "URL to the sheepdog image",
-        },
-        { /* end of list */ }
-    },
-};
-
-static int sd_open(BlockDriverState *bs, QDict *options, int flags,
-                   Error **errp)
-{
-    int ret, fd;
-    uint32_t vid = 0;
-    BDRVSheepdogState *s = bs->opaque;
-    char vdi[SD_MAX_VDI_LEN], tag[SD_MAX_VDI_TAG_LEN];
-    uint32_t snapid;
-    char *buf = NULL;
-    QemuOpts *opts;
-    Error *local_err = NULL;
-    const char *filename;
-
-    s->bs = bs;
-    s->aio_context = bdrv_get_aio_context(bs);
-
-    opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
-    qemu_opts_absorb_qdict(opts, options, &local_err);
-    if (local_err) {
-        error_propagate(errp, local_err);
-        ret = -EINVAL;
-        goto out;
-    }
-
-    filename = qemu_opt_get(opts, "filename");
-
-    QLIST_INIT(&s->inflight_aio_head);
-    QLIST_INIT(&s->failed_aio_head);
-    QLIST_INIT(&s->inflight_aiocb_head);
-    s->fd = -1;
-
-    memset(vdi, 0, sizeof(vdi));
-    memset(tag, 0, sizeof(tag));
-
-    if (strstr(filename, "://")) {
-        ret = sd_parse_uri(s, filename, vdi, &snapid, tag);
-    } else {
-        ret = parse_vdiname(s, filename, vdi, &snapid, tag);
-    }
-    if (ret < 0) {
-        error_setg(errp, "Can't parse filename");
-        goto out;
-    }
-    s->fd = get_sheep_fd(s, errp);
-    if (s->fd < 0) {
-        ret = s->fd;
-        goto out;
-    }
-
-    ret = find_vdi_name(s, vdi, snapid, tag, &vid, true, errp);
-    if (ret) {
-        goto out;
-    }
-
-    /*
-     * QEMU block layer emulates writethrough cache as 'writeback + flush', so
-     * we always set SD_FLAG_CMD_CACHE (writeback cache) as default.
-     */
-    s->cache_flags = SD_FLAG_CMD_CACHE;
-    if (flags & BDRV_O_NOCACHE) {
-        s->cache_flags = SD_FLAG_CMD_DIRECT;
-    }
-    s->discard_supported = true;
-
-    if (snapid || tag[0] != '\0') {
-        DPRINTF("%" PRIx32 " snapshot inode was open.\n", vid);
-        s->is_snapshot = true;
-    }
-
-    fd = connect_to_sdog(s, errp);
-    if (fd < 0) {
-        ret = fd;
-        goto out;
-    }
-
-    buf = g_malloc(SD_INODE_SIZE);
-    ret = read_object(fd, s->aio_context, buf, vid_to_vdi_oid(vid),
-                      0, SD_INODE_SIZE, 0, s->cache_flags);
-
-    closesocket(fd);
-
-    if (ret) {
-        error_setg(errp, "Can't read snapshot inode");
-        goto out;
-    }
-
-    memcpy(&s->inode, buf, sizeof(s->inode));
-
-    bs->total_sectors = s->inode.vdi_size / BDRV_SECTOR_SIZE;
-    pstrcpy(s->name, sizeof(s->name), vdi);
-    qemu_co_mutex_init(&s->lock);
-    qemu_co_queue_init(&s->overlapping_queue);
-    qemu_opts_del(opts);
-    g_free(buf);
-    return 0;
-out:
-    aio_set_fd_handler(bdrv_get_aio_context(bs), s->fd,
-                       false, NULL, NULL, NULL);
-    if (s->fd >= 0) {
-        closesocket(s->fd);
-    }
-    qemu_opts_del(opts);
-    g_free(buf);
-    return ret;
-}
-
-static int sd_reopen_prepare(BDRVReopenState *state, BlockReopenQueue *queue,
-                             Error **errp)
-{
-    BDRVSheepdogState *s = state->bs->opaque;
-    BDRVSheepdogReopenState *re_s;
-    int ret = 0;
-
-    re_s = state->opaque = g_new0(BDRVSheepdogReopenState, 1);
-
-    re_s->cache_flags = SD_FLAG_CMD_CACHE;
-    if (state->flags & BDRV_O_NOCACHE) {
-        re_s->cache_flags = SD_FLAG_CMD_DIRECT;
-    }
-
-    re_s->fd = get_sheep_fd(s, errp);
-    if (re_s->fd < 0) {
-        ret = re_s->fd;
-        return ret;
-    }
-
-    return ret;
-}
-
-static void sd_reopen_commit(BDRVReopenState *state)
-{
-    BDRVSheepdogReopenState *re_s = state->opaque;
-    BDRVSheepdogState *s = state->bs->opaque;
-
-    if (s->fd) {
-        aio_set_fd_handler(s->aio_context, s->fd, false,
-                           NULL, NULL, NULL);
-        closesocket(s->fd);
-    }
-
-    s->fd = re_s->fd;
-    s->cache_flags = re_s->cache_flags;
-
-    g_free(state->opaque);
-    state->opaque = NULL;
-
-    return;
-}
-
-static void sd_reopen_abort(BDRVReopenState *state)
-{
-    BDRVSheepdogReopenState *re_s = state->opaque;
-    BDRVSheepdogState *s = state->bs->opaque;
-
-    if (re_s == NULL) {
-        return;
-    }
-
-    if (re_s->fd) {
-        aio_set_fd_handler(s->aio_context, re_s->fd, false,
-                           NULL, NULL, NULL);
-        closesocket(re_s->fd);
-    }
-
-    g_free(state->opaque);
-    state->opaque = NULL;
-
-    return;
-}
-
-static int do_sd_create(BDRVSheepdogState *s, uint32_t *vdi_id, int snapshot,
-                        Error **errp)
-{
-    SheepdogVdiReq hdr;
-    SheepdogVdiRsp *rsp = (SheepdogVdiRsp *)&hdr;
-    int fd, ret;
-    unsigned int wlen, rlen = 0;
-    char buf[SD_MAX_VDI_LEN];
-
-    fd = connect_to_sdog(s, errp);
-    if (fd < 0) {
-        return fd;
-    }
-
-    /* FIXME: would it be better to fail (e.g., return -EIO) when filename
-     * does not fit in buf?  For now, just truncate and avoid buffer overrun.
-     */
-    memset(buf, 0, sizeof(buf));
-    pstrcpy(buf, sizeof(buf), s->name);
-
-    memset(&hdr, 0, sizeof(hdr));
-    hdr.opcode = SD_OP_NEW_VDI;
-    hdr.base_vdi_id = s->inode.vdi_id;
-
-    wlen = SD_MAX_VDI_LEN;
-
-    hdr.flags = SD_FLAG_CMD_WRITE;
-    hdr.snapid = snapshot;
-
-    hdr.data_length = wlen;
-    hdr.vdi_size = s->inode.vdi_size;
-    hdr.copy_policy = s->inode.copy_policy;
-    hdr.copies = s->inode.nr_copies;
-    hdr.block_size_shift = s->inode.block_size_shift;
-
-    ret = do_req(fd, s->aio_context, (SheepdogReq *)&hdr, buf, &wlen, &rlen);
-
-    closesocket(fd);
-
-    if (ret) {
-        error_setg_errno(errp, -ret, "create failed");
-        return ret;
-    }
-
-    if (rsp->result != SD_RES_SUCCESS) {
-        error_setg(errp, "%s, %s", sd_strerror(rsp->result), s->inode.name);
-        return -EIO;
-    }
-
-    if (vdi_id) {
-        *vdi_id = rsp->vdi_id;
-    }
-
-    return 0;
-}
-
-static int sd_prealloc(const char *filename, Error **errp)
-{
-    BlockBackend *blk = NULL;
-    BDRVSheepdogState *base = NULL;
-    unsigned long buf_size;
-    uint32_t idx, max_idx;
-    uint32_t object_size;
-    int64_t vdi_size;
-    void *buf = NULL;
-    int ret;
-
-    blk = blk_new_open(filename, NULL, NULL,
-                       BDRV_O_RDWR | BDRV_O_PROTOCOL, errp);
-    if (blk == NULL) {
-        ret = -EIO;
-        goto out_with_err_set;
-    }
-
-    blk_set_allow_write_beyond_eof(blk, true);
-
-    vdi_size = blk_getlength(blk);
-    if (vdi_size < 0) {
-        ret = vdi_size;
-        goto out;
-    }
-
-    base = blk_bs(blk)->opaque;
-    object_size = (UINT32_C(1) << base->inode.block_size_shift);
-    buf_size = MIN(object_size, SD_DATA_OBJ_SIZE);
-    buf = g_malloc0(buf_size);
-
-    max_idx = DIV_ROUND_UP(vdi_size, buf_size);
-
-    for (idx = 0; idx < max_idx; idx++) {
-        /*
-         * The created image can be a cloned image, so we need to read
-         * a data from the source image.
-         */
-        ret = blk_pread(blk, idx * buf_size, buf, buf_size);
-        if (ret < 0) {
-            goto out;
-        }
-        ret = blk_pwrite(blk, idx * buf_size, buf, buf_size);
-        if (ret < 0) {
-            goto out;
-        }
-    }
-
-    ret = 0;
-out:
-    if (ret < 0) {
-        error_setg_errno(errp, -ret, "Can't pre-allocate");
-    }
-out_with_err_set:
-    if (blk) {
-        blk_unref(blk);
-    }
-    g_free(buf);
-
-    return ret;
-}
-
-/*
- * Sheepdog support two kinds of redundancy, full replication and erasure
- * coding.
- *
- * # create a fully replicated vdi with x copies
- * -o redundancy=x (1 <= x <= SD_MAX_COPIES)
- *
- * # create a erasure coded vdi with x data strips and y parity strips
- * -o redundancy=x:y (x must be one of {2,4,8,16} and 1 <= y < SD_EC_MAX_STRIP)
- */
-static int parse_redundancy(BDRVSheepdogState *s, const char *opt)
-{
-    struct SheepdogInode *inode = &s->inode;
-    const char *n1, *n2;
-    long copy, parity;
-    char p[10];
-
-    pstrcpy(p, sizeof(p), opt);
-    n1 = strtok(p, ":");
-    n2 = strtok(NULL, ":");
-
-    if (!n1) {
-        return -EINVAL;
-    }
-
-    copy = strtol(n1, NULL, 10);
-    if (copy > SD_MAX_COPIES || copy < 1) {
-        return -EINVAL;
-    }
-    if (!n2) {
-        inode->copy_policy = 0;
-        inode->nr_copies = copy;
-        return 0;
-    }
-
-    if (copy != 2 && copy != 4 && copy != 8 && copy != 16) {
-        return -EINVAL;
-    }
-
-    parity = strtol(n2, NULL, 10);
-    if (parity >= SD_EC_MAX_STRIP || parity < 1) {
-        return -EINVAL;
-    }
-
-    /*
-     * 4 bits for parity and 4 bits for data.
-     * We have to compress upper data bits because it can't represent 16
-     */
-    inode->copy_policy = ((copy / 2) << 4) + parity;
-    inode->nr_copies = copy + parity;
-
-    return 0;
-}
-
-static int parse_block_size_shift(BDRVSheepdogState *s, QemuOpts *opt)
-{
-    struct SheepdogInode *inode = &s->inode;
-    uint64_t object_size;
-    int obj_order;
-
-    object_size = qemu_opt_get_size_del(opt, BLOCK_OPT_OBJECT_SIZE, 0);
-    if (object_size) {
-        if ((object_size - 1) & object_size) {    /* not a power of 2? */
-            return -EINVAL;
-        }
-        obj_order = ctz32(object_size);
-        if (obj_order < 20 || obj_order > 31) {
-            return -EINVAL;
-        }
-        inode->block_size_shift = (uint8_t)obj_order;
-    }
-
-    return 0;
-}
-
-static int sd_create(const char *filename, QemuOpts *opts,
-                     Error **errp)
-{
-    int ret = 0;
-    uint32_t vid = 0;
-    char *backing_file = NULL;
-    char *buf = NULL;
-    BDRVSheepdogState *s;
-    char tag[SD_MAX_VDI_TAG_LEN];
-    uint32_t snapid;
-    uint64_t max_vdi_size;
-    bool prealloc = false;
-
-    s = g_new0(BDRVSheepdogState, 1);
-
-    memset(tag, 0, sizeof(tag));
-    if (strstr(filename, "://")) {
-        ret = sd_parse_uri(s, filename, s->name, &snapid, tag);
-    } else {
-        ret = parse_vdiname(s, filename, s->name, &snapid, tag);
-    }
-    if (ret < 0) {
-        error_setg(errp, "Can't parse filename");
-        goto out;
-    }
-
-    s->inode.vdi_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
-                                 BDRV_SECTOR_SIZE);
-    backing_file = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE);
-    buf = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC);
-    if (!buf || !strcmp(buf, "off")) {
-        prealloc = false;
-    } else if (!strcmp(buf, "full")) {
-        prealloc = true;
-    } else {
-        error_setg(errp, "Invalid preallocation mode: '%s'", buf);
-        ret = -EINVAL;
-        goto out;
-    }
-
-    g_free(buf);
-    buf = qemu_opt_get_del(opts, BLOCK_OPT_REDUNDANCY);
-    if (buf) {
-        ret = parse_redundancy(s, buf);
-        if (ret < 0) {
-            error_setg(errp, "Invalid redundancy mode: '%s'", buf);
-            goto out;
-        }
-    }
-    ret = parse_block_size_shift(s, opts);
-    if (ret < 0) {
-        error_setg(errp, "Invalid object_size."
-                         " obect_size needs to be power of 2"
-                         " and be limited from 2^20 to 2^31");
-        goto out;
-    }
-
-    if (backing_file) {
-        BlockBackend *blk;
-        BDRVSheepdogState *base;
-        BlockDriver *drv;
-
-        /* Currently, only Sheepdog backing image is supported. */
-        drv = bdrv_find_protocol(backing_file, true, NULL);
-        if (!drv || strcmp(drv->protocol_name, "sheepdog") != 0) {
-            error_setg(errp, "backing_file must be a sheepdog image");
-            ret = -EINVAL;
-            goto out;
-        }
-
-        blk = blk_new_open(backing_file, NULL, NULL,
-                           BDRV_O_PROTOCOL, errp);
-        if (blk == NULL) {
-            ret = -EIO;
-            goto out;
-        }
-
-        base = blk_bs(blk)->opaque;
-
-        if (!is_snapshot(&base->inode)) {
-            error_setg(errp, "cannot clone from a non snapshot vdi");
-            blk_unref(blk);
-            ret = -EINVAL;
-            goto out;
-        }
-        s->inode.vdi_id = base->inode.vdi_id;
-        blk_unref(blk);
-    }
-
-    s->aio_context = qemu_get_aio_context();
-
-    /* if block_size_shift is not specified, get cluster default value */
-    if (s->inode.block_size_shift == 0) {
-        SheepdogVdiReq hdr;
-        SheepdogClusterRsp *rsp = (SheepdogClusterRsp *)&hdr;
-        Error *local_err = NULL;
-        int fd;
-        unsigned int wlen = 0, rlen = 0;
-
-        fd = connect_to_sdog(s, &local_err);
-        if (fd < 0) {
-            error_report_err(local_err);
-            ret = -EIO;
-            goto out;
-        }
-
-        memset(&hdr, 0, sizeof(hdr));
-        hdr.opcode = SD_OP_GET_CLUSTER_DEFAULT;
-        hdr.proto_ver = SD_PROTO_VER;
-
-        ret = do_req(fd, s->aio_context, (SheepdogReq *)&hdr,
-                     NULL, &wlen, &rlen);
-        closesocket(fd);
-        if (ret) {
-            error_setg_errno(errp, -ret, "failed to get cluster default");
-            goto out;
-        }
-        if (rsp->result == SD_RES_SUCCESS) {
-            s->inode.block_size_shift = rsp->block_size_shift;
-        } else {
-            s->inode.block_size_shift = SD_DEFAULT_BLOCK_SIZE_SHIFT;
-        }
-    }
-
-    max_vdi_size = (UINT64_C(1) << s->inode.block_size_shift) * MAX_DATA_OBJS;
-
-    if (s->inode.vdi_size > max_vdi_size) {
-        error_setg(errp, "An image is too large."
-                         " The maximum image size is %"PRIu64 "GB",
-                         max_vdi_size / 1024 / 1024 / 1024);
-        ret = -EINVAL;
-        goto out;
-    }
-
-    ret = do_sd_create(s, &vid, 0, errp);
-    if (ret) {
-        goto out;
-    }
-
-    if (prealloc) {
-        ret = sd_prealloc(filename, errp);
-    }
-out:
-    g_free(backing_file);
-    g_free(buf);
-    g_free(s);
-    return ret;
-}
-
-static void sd_close(BlockDriverState *bs)
-{
-    Error *local_err = NULL;
-    BDRVSheepdogState *s = bs->opaque;
-    SheepdogVdiReq hdr;
-    SheepdogVdiRsp *rsp = (SheepdogVdiRsp *)&hdr;
-    unsigned int wlen, rlen = 0;
-    int fd, ret;
-
-    DPRINTF("%s\n", s->name);
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        return;
-    }
-
-    memset(&hdr, 0, sizeof(hdr));
-
-    hdr.opcode = SD_OP_RELEASE_VDI;
-    hdr.type = LOCK_TYPE_NORMAL;
-    hdr.base_vdi_id = s->inode.vdi_id;
-    wlen = strlen(s->name) + 1;
-    hdr.data_length = wlen;
-    hdr.flags = SD_FLAG_CMD_WRITE;
-
-    ret = do_req(fd, s->aio_context, (SheepdogReq *)&hdr,
-                 s->name, &wlen, &rlen);
-
-    closesocket(fd);
-
-    if (!ret && rsp->result != SD_RES_SUCCESS &&
-        rsp->result != SD_RES_VDI_NOT_LOCKED) {
-        error_report("%s, %s", sd_strerror(rsp->result), s->name);
-    }
-
-    aio_set_fd_handler(bdrv_get_aio_context(bs), s->fd,
-                       false, NULL, NULL, NULL);
-    closesocket(s->fd);
-    g_free(s->host_spec);
-}
-
-static int64_t sd_getlength(BlockDriverState *bs)
-{
-    BDRVSheepdogState *s = bs->opaque;
-
-    return s->inode.vdi_size;
-}
-
-static int sd_truncate(BlockDriverState *bs, int64_t offset)
-{
-    Error *local_err = NULL;
-    BDRVSheepdogState *s = bs->opaque;
-    int ret, fd;
-    unsigned int datalen;
-    uint64_t max_vdi_size;
-
-    max_vdi_size = (UINT64_C(1) << s->inode.block_size_shift) * MAX_DATA_OBJS;
-    if (offset < s->inode.vdi_size) {
-        error_report("shrinking is not supported");
-        return -EINVAL;
-    } else if (offset > max_vdi_size) {
-        error_report("too big image size");
-        return -EINVAL;
-    }
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        return fd;
-    }
-
-    /* we don't need to update entire object */
-    datalen = SD_INODE_SIZE - sizeof(s->inode.data_vdi_id);
-    s->inode.vdi_size = offset;
-    ret = write_object(fd, s->aio_context, (char *)&s->inode,
-                       vid_to_vdi_oid(s->inode.vdi_id), s->inode.nr_copies,
-                       datalen, 0, false, s->cache_flags);
-    close(fd);
-
-    if (ret < 0) {
-        error_report("failed to update an inode.");
-    }
-
-    return ret;
-}
-
-/*
- * This function is called after writing data objects.  If we need to
- * update metadata, this sends a write request to the vdi object.
- * Otherwise, this switches back to sd_co_readv/writev.
- */
-static void coroutine_fn sd_write_done(SheepdogAIOCB *acb)
-{
-    BDRVSheepdogState *s = acb->common.bs->opaque;
-    struct iovec iov;
-    AIOReq *aio_req;
-    uint32_t offset, data_len, mn, mx;
-
-    mn = acb->min_dirty_data_idx;
-    mx = acb->max_dirty_data_idx;
-    if (mn <= mx) {
-        /* we need to update the vdi object. */
-        offset = sizeof(s->inode) - sizeof(s->inode.data_vdi_id) +
-            mn * sizeof(s->inode.data_vdi_id[0]);
-        data_len = (mx - mn + 1) * sizeof(s->inode.data_vdi_id[0]);
-
-        acb->min_dirty_data_idx = UINT32_MAX;
-        acb->max_dirty_data_idx = 0;
-
-        iov.iov_base = &s->inode;
-        iov.iov_len = sizeof(s->inode);
-        aio_req = alloc_aio_req(s, acb, vid_to_vdi_oid(s->inode.vdi_id),
-                                data_len, offset, 0, false, 0, offset);
-        QLIST_INSERT_HEAD(&s->inflight_aio_head, aio_req, aio_siblings);
-        add_aio_request(s, aio_req, &iov, 1, AIOCB_WRITE_UDATA);
-
-        acb->aio_done_func = sd_finish_aiocb;
-        acb->aiocb_type = AIOCB_WRITE_UDATA;
-        return;
-    }
-
-    sd_finish_aiocb(acb);
-}
-
-/* Delete current working VDI on the snapshot chain */
-static bool sd_delete(BDRVSheepdogState *s)
-{
-    Error *local_err = NULL;
-    unsigned int wlen = SD_MAX_VDI_LEN, rlen = 0;
-    SheepdogVdiReq hdr = {
-        .opcode = SD_OP_DEL_VDI,
-        .base_vdi_id = s->inode.vdi_id,
-        .data_length = wlen,
-        .flags = SD_FLAG_CMD_WRITE,
-    };
-    SheepdogVdiRsp *rsp = (SheepdogVdiRsp *)&hdr;
-    int fd, ret;
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        return false;
-    }
-
-    ret = do_req(fd, s->aio_context, (SheepdogReq *)&hdr,
-                 s->name, &wlen, &rlen);
-    closesocket(fd);
-    if (ret) {
-        return false;
-    }
-    switch (rsp->result) {
-    case SD_RES_NO_VDI:
-        error_report("%s was already deleted", s->name);
-        /* fall through */
-    case SD_RES_SUCCESS:
-        break;
-    default:
-        error_report("%s, %s", sd_strerror(rsp->result), s->name);
-        return false;
-    }
-
-    return true;
-}
-
-/*
- * Create a writable VDI from a snapshot
- */
-static int sd_create_branch(BDRVSheepdogState *s)
-{
-    Error *local_err = NULL;
-    int ret, fd;
-    uint32_t vid;
-    char *buf;
-    bool deleted;
-
-    DPRINTF("%" PRIx32 " is snapshot.\n", s->inode.vdi_id);
-
-    buf = g_malloc(SD_INODE_SIZE);
-
-    /*
-     * Even If deletion fails, we will just create extra snapshot based on
-     * the working VDI which was supposed to be deleted. So no need to
-     * false bail out.
-     */
-    deleted = sd_delete(s);
-    ret = do_sd_create(s, &vid, !deleted, &local_err);
-    if (ret) {
-        error_report_err(local_err);
-        goto out;
-    }
-
-    DPRINTF("%" PRIx32 " is created.\n", vid);
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        ret = fd;
-        goto out;
-    }
-
-    ret = read_object(fd, s->aio_context, buf, vid_to_vdi_oid(vid),
-                      s->inode.nr_copies, SD_INODE_SIZE, 0, s->cache_flags);
-
-    closesocket(fd);
-
-    if (ret < 0) {
-        goto out;
-    }
-
-    memcpy(&s->inode, buf, sizeof(s->inode));
-
-    s->is_snapshot = false;
-    ret = 0;
-    DPRINTF("%" PRIx32 " was newly created.\n", s->inode.vdi_id);
-
-out:
-    g_free(buf);
-
-    return ret;
-}
-
-/*
- * Send I/O requests to the server.
- *
- * This function sends requests to the server, links the requests to
- * the inflight_list in BDRVSheepdogState, and exits without
- * waiting the response.  The responses are received in the
- * `aio_read_response' function which is called from the main loop as
- * a fd handler.
- *
- * Returns 1 when we need to wait a response, 0 when there is no sent
- * request and -errno in error cases.
- */
-static int coroutine_fn sd_co_rw_vector(void *p)
-{
-    SheepdogAIOCB *acb = p;
-    int ret = 0;
-    unsigned long len, done = 0, total = acb->nb_sectors * BDRV_SECTOR_SIZE;
-    unsigned long idx;
-    uint32_t object_size;
-    uint64_t oid;
-    uint64_t offset;
-    BDRVSheepdogState *s = acb->common.bs->opaque;
-    SheepdogInode *inode = &s->inode;
-    AIOReq *aio_req;
-
-    if (acb->aiocb_type == AIOCB_WRITE_UDATA && s->is_snapshot) {
-        /*
-         * In the case we open the snapshot VDI, Sheepdog creates the
-         * writable VDI when we do a write operation first.
-         */
-        ret = sd_create_branch(s);
-        if (ret) {
-            acb->ret = -EIO;
-            goto out;
-        }
-    }
-
-    object_size = (UINT32_C(1) << inode->block_size_shift);
-    idx = acb->sector_num * BDRV_SECTOR_SIZE / object_size;
-    offset = (acb->sector_num * BDRV_SECTOR_SIZE) % object_size;
-
-    /*
-     * Make sure we don't free the aiocb before we are done with all requests.
-     * This additional reference is dropped at the end of this function.
-     */
-    acb->nr_pending++;
-
-    while (done != total) {
-        uint8_t flags = 0;
-        uint64_t old_oid = 0;
-        bool create = false;
-
-        oid = vid_to_data_oid(inode->data_vdi_id[idx], idx);
-
-        len = MIN(total - done, object_size - offset);
-
-        switch (acb->aiocb_type) {
-        case AIOCB_READ_UDATA:
-            if (!inode->data_vdi_id[idx]) {
-                qemu_iovec_memset(acb->qiov, done, 0, len);
-                goto done;
-            }
-            break;
-        case AIOCB_WRITE_UDATA:
-            if (!inode->data_vdi_id[idx]) {
-                create = true;
-            } else if (!is_data_obj_writable(inode, idx)) {
-                /* Copy-On-Write */
-                create = true;
-                old_oid = oid;
-                flags = SD_FLAG_CMD_COW;
-            }
-            break;
-        case AIOCB_DISCARD_OBJ:
-            /*
-             * We discard the object only when the whole object is
-             * 1) allocated 2) trimmed. Otherwise, simply skip it.
-             */
-            if (len != object_size || inode->data_vdi_id[idx] == 0) {
-                goto done;
-            }
-            break;
-        default:
-            break;
-        }
-
-        if (create) {
-            DPRINTF("update ino (%" PRIu32 ") %" PRIu64 " %" PRIu64 " %ld\n",
-                    inode->vdi_id, oid,
-                    vid_to_data_oid(inode->data_vdi_id[idx], idx), idx);
-            oid = vid_to_data_oid(inode->vdi_id, idx);
-            DPRINTF("new oid %" PRIx64 "\n", oid);
-        }
-
-        aio_req = alloc_aio_req(s, acb, oid, len, offset, flags, create,
-                                old_oid,
-                                acb->aiocb_type == AIOCB_DISCARD_OBJ ?
-                                0 : done);
-        QLIST_INSERT_HEAD(&s->inflight_aio_head, aio_req, aio_siblings);
-
-        add_aio_request(s, aio_req, acb->qiov->iov, acb->qiov->niov,
-                        acb->aiocb_type);
-    done:
-        offset = 0;
-        idx++;
-        done += len;
-    }
-out:
-    if (!--acb->nr_pending) {
-        return acb->ret;
-    }
-    return 1;
-}
-
-static bool check_overlapping_aiocb(BDRVSheepdogState *s, SheepdogAIOCB *aiocb)
-{
-    SheepdogAIOCB *cb;
-
-    QLIST_FOREACH(cb, &s->inflight_aiocb_head, aiocb_siblings) {
-        if (AIOCBOverlapping(aiocb, cb)) {
-            return true;
-        }
-    }
-
-    QLIST_INSERT_HEAD(&s->inflight_aiocb_head, aiocb, aiocb_siblings);
-    return false;
-}
-
-static coroutine_fn int sd_co_writev(BlockDriverState *bs, int64_t sector_num,
-                        int nb_sectors, QEMUIOVector *qiov)
-{
-    SheepdogAIOCB *acb;
-    int ret;
-    int64_t offset = (sector_num + nb_sectors) * BDRV_SECTOR_SIZE;
-    BDRVSheepdogState *s = bs->opaque;
-
-    if (offset > s->inode.vdi_size) {
-        ret = sd_truncate(bs, offset);
-        if (ret < 0) {
-            return ret;
-        }
-    }
-
-    acb = sd_aio_setup(bs, qiov, sector_num, nb_sectors);
-    acb->aio_done_func = sd_write_done;
-    acb->aiocb_type = AIOCB_WRITE_UDATA;
-
-retry:
-    if (check_overlapping_aiocb(s, acb)) {
-        qemu_co_queue_wait(&s->overlapping_queue);
-        goto retry;
-    }
-
-    ret = sd_co_rw_vector(acb);
-    if (ret <= 0) {
-        QLIST_REMOVE(acb, aiocb_siblings);
-        qemu_co_queue_restart_all(&s->overlapping_queue);
-        qemu_aio_unref(acb);
-        return ret;
-    }
-
-    qemu_coroutine_yield();
-
-    QLIST_REMOVE(acb, aiocb_siblings);
-    qemu_co_queue_restart_all(&s->overlapping_queue);
-
-    return acb->ret;
-}
-
-static coroutine_fn int sd_co_readv(BlockDriverState *bs, int64_t sector_num,
-                       int nb_sectors, QEMUIOVector *qiov)
-{
-    SheepdogAIOCB *acb;
-    int ret;
-    BDRVSheepdogState *s = bs->opaque;
-
-    acb = sd_aio_setup(bs, qiov, sector_num, nb_sectors);
-    acb->aiocb_type = AIOCB_READ_UDATA;
-    acb->aio_done_func = sd_finish_aiocb;
-
-retry:
-    if (check_overlapping_aiocb(s, acb)) {
-        qemu_co_queue_wait(&s->overlapping_queue);
-        goto retry;
-    }
-
-    ret = sd_co_rw_vector(acb);
-    if (ret <= 0) {
-        QLIST_REMOVE(acb, aiocb_siblings);
-        qemu_co_queue_restart_all(&s->overlapping_queue);
-        qemu_aio_unref(acb);
-        return ret;
-    }
-
-    qemu_coroutine_yield();
-
-    QLIST_REMOVE(acb, aiocb_siblings);
-    qemu_co_queue_restart_all(&s->overlapping_queue);
-    return acb->ret;
-}
-
-static int coroutine_fn sd_co_flush_to_disk(BlockDriverState *bs)
-{
-    BDRVSheepdogState *s = bs->opaque;
-    SheepdogAIOCB *acb;
-    AIOReq *aio_req;
-
-    if (s->cache_flags != SD_FLAG_CMD_CACHE) {
-        return 0;
-    }
-
-    acb = sd_aio_setup(bs, NULL, 0, 0);
-    acb->aiocb_type = AIOCB_FLUSH_CACHE;
-    acb->aio_done_func = sd_finish_aiocb;
-
-    aio_req = alloc_aio_req(s, acb, vid_to_vdi_oid(s->inode.vdi_id),
-                            0, 0, 0, false, 0, 0);
-    QLIST_INSERT_HEAD(&s->inflight_aio_head, aio_req, aio_siblings);
-    add_aio_request(s, aio_req, NULL, 0, acb->aiocb_type);
-
-    qemu_coroutine_yield();
-    return acb->ret;
-}
-
-static int sd_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
-{
-    Error *local_err = NULL;
-    BDRVSheepdogState *s = bs->opaque;
-    int ret, fd;
-    uint32_t new_vid;
-    SheepdogInode *inode;
-    unsigned int datalen;
-
-    DPRINTF("sn_info: name %s id_str %s s: name %s vm_state_size %" PRId64 " "
-            "is_snapshot %d\n", sn_info->name, sn_info->id_str,
-            s->name, sn_info->vm_state_size, s->is_snapshot);
-
-    if (s->is_snapshot) {
-        error_report("You can't create a snapshot of a snapshot VDI, "
-                     "%s (%" PRIu32 ").", s->name, s->inode.vdi_id);
-
-        return -EINVAL;
-    }
-
-    DPRINTF("%s %s\n", sn_info->name, sn_info->id_str);
-
-    s->inode.vm_state_size = sn_info->vm_state_size;
-    s->inode.vm_clock_nsec = sn_info->vm_clock_nsec;
-    /* It appears that inode.tag does not require a NUL terminator,
-     * which means this use of strncpy is ok.
-     */
-    strncpy(s->inode.tag, sn_info->name, sizeof(s->inode.tag));
-    /* we don't need to update entire object */
-    datalen = SD_INODE_SIZE - sizeof(s->inode.data_vdi_id);
-    inode = g_malloc(datalen);
-
-    /* refresh inode. */
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        ret = fd;
-        goto cleanup;
-    }
-
-    ret = write_object(fd, s->aio_context, (char *)&s->inode,
-                       vid_to_vdi_oid(s->inode.vdi_id), s->inode.nr_copies,
-                       datalen, 0, false, s->cache_flags);
-    if (ret < 0) {
-        error_report("failed to write snapshot's inode.");
-        goto cleanup;
-    }
-
-    ret = do_sd_create(s, &new_vid, 1, &local_err);
-    if (ret < 0) {
-        error_reportf_err(local_err,
-                          "failed to create inode for snapshot: ");
-        goto cleanup;
-    }
-
-    ret = read_object(fd, s->aio_context, (char *)inode,
-                      vid_to_vdi_oid(new_vid), s->inode.nr_copies, datalen, 0,
-                      s->cache_flags);
-
-    if (ret < 0) {
-        error_report("failed to read new inode info. %s", strerror(errno));
-        goto cleanup;
-    }
-
-    memcpy(&s->inode, inode, datalen);
-    DPRINTF("s->inode: name %s snap_id %x oid %x\n",
-            s->inode.name, s->inode.snap_id, s->inode.vdi_id);
-
-cleanup:
-    g_free(inode);
-    closesocket(fd);
-    return ret;
-}
-
-/*
- * We implement rollback(loadvm) operation to the specified snapshot by
- * 1) switch to the snapshot
- * 2) rely on sd_create_branch to delete working VDI and
- * 3) create a new working VDI based on the specified snapshot
- */
-static int sd_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
-{
-    BDRVSheepdogState *s = bs->opaque;
-    BDRVSheepdogState *old_s;
-    char tag[SD_MAX_VDI_TAG_LEN];
-    uint32_t snapid = 0;
-    int ret = 0;
-
-    old_s = g_new(BDRVSheepdogState, 1);
-
-    memcpy(old_s, s, sizeof(BDRVSheepdogState));
-
-    snapid = strtoul(snapshot_id, NULL, 10);
-    if (snapid) {
-        tag[0] = 0;
-    } else {
-        pstrcpy(tag, sizeof(tag), snapshot_id);
-    }
-
-    ret = reload_inode(s, snapid, tag);
-    if (ret) {
-        goto out;
-    }
-
-    ret = sd_create_branch(s);
-    if (ret) {
-        goto out;
-    }
-
-    g_free(old_s);
-
-    return 0;
-out:
-    /* recover bdrv_sd_state */
-    memcpy(s, old_s, sizeof(BDRVSheepdogState));
-    g_free(old_s);
-
-    error_report("failed to open. recover old bdrv_sd_state.");
-
-    return ret;
-}
-
-#define NR_BATCHED_DISCARD 128
-
-static bool remove_objects(BDRVSheepdogState *s)
-{
-    int fd, i = 0, nr_objs = 0;
-    Error *local_err = NULL;
-    int ret = 0;
-    bool result = true;
-    SheepdogInode *inode = &s->inode;
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        return false;
-    }
-
-    nr_objs = count_data_objs(inode);
-    while (i < nr_objs) {
-        int start_idx, nr_filled_idx;
-
-        while (i < nr_objs && !inode->data_vdi_id[i]) {
-            i++;
-        }
-        start_idx = i;
-
-        nr_filled_idx = 0;
-        while (i < nr_objs && nr_filled_idx < NR_BATCHED_DISCARD) {
-            if (inode->data_vdi_id[i]) {
-                inode->data_vdi_id[i] = 0;
-                nr_filled_idx++;
-            }
-
-            i++;
-        }
-
-        ret = write_object(fd, s->aio_context,
-                           (char *)&inode->data_vdi_id[start_idx],
-                           vid_to_vdi_oid(s->inode.vdi_id), inode->nr_copies,
-                           (i - start_idx) * sizeof(uint32_t),
-                           offsetof(struct SheepdogInode,
-                                    data_vdi_id[start_idx]),
-                           false, s->cache_flags);
-        if (ret < 0) {
-            error_report("failed to discard snapshot inode.");
-            result = false;
-            goto out;
-        }
-    }
-
-out:
-    closesocket(fd);
-    return result;
-}
-
-static int sd_snapshot_delete(BlockDriverState *bs,
-                              const char *snapshot_id,
-                              const char *name,
-                              Error **errp)
-{
-    unsigned long snap_id = 0;
-    char snap_tag[SD_MAX_VDI_TAG_LEN];
-    Error *local_err = NULL;
-    int fd, ret;
-    char buf[SD_MAX_VDI_LEN + SD_MAX_VDI_TAG_LEN];
-    BDRVSheepdogState *s = bs->opaque;
-    unsigned int wlen = SD_MAX_VDI_LEN + SD_MAX_VDI_TAG_LEN, rlen = 0;
-    uint32_t vid;
-    SheepdogVdiReq hdr = {
-        .opcode = SD_OP_DEL_VDI,
-        .data_length = wlen,
-        .flags = SD_FLAG_CMD_WRITE,
-    };
-    SheepdogVdiRsp *rsp = (SheepdogVdiRsp *)&hdr;
-
-    if (!remove_objects(s)) {
-        return -1;
-    }
-
-    memset(buf, 0, sizeof(buf));
-    memset(snap_tag, 0, sizeof(snap_tag));
-    pstrcpy(buf, SD_MAX_VDI_LEN, s->name);
-    ret = qemu_strtoul(snapshot_id, NULL, 10, &snap_id);
-    if (ret || snap_id > UINT32_MAX) {
-        error_setg(errp, "Invalid snapshot ID: %s",
-                         snapshot_id ? snapshot_id : "<null>");
-        return -EINVAL;
-    }
-
-    if (snap_id) {
-        hdr.snapid = (uint32_t) snap_id;
-    } else {
-        pstrcpy(snap_tag, sizeof(snap_tag), snapshot_id);
-        pstrcpy(buf + SD_MAX_VDI_LEN, SD_MAX_VDI_TAG_LEN, snap_tag);
-    }
-
-    ret = find_vdi_name(s, s->name, snap_id, snap_tag, &vid, true,
-                        &local_err);
-    if (ret) {
-        return ret;
-    }
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        return -1;
-    }
-
-    ret = do_req(fd, s->aio_context, (SheepdogReq *)&hdr,
-                 buf, &wlen, &rlen);
-    closesocket(fd);
-    if (ret) {
-        return ret;
-    }
-
-    switch (rsp->result) {
-    case SD_RES_NO_VDI:
-        error_report("%s was already deleted", s->name);
-    case SD_RES_SUCCESS:
-        break;
-    default:
-        error_report("%s, %s", sd_strerror(rsp->result), s->name);
-        return -1;
-    }
-
-    return ret;
-}
-
-static int sd_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab)
-{
-    Error *local_err = NULL;
-    BDRVSheepdogState *s = bs->opaque;
-    SheepdogReq req;
-    int fd, nr = 1024, ret, max = BITS_TO_LONGS(SD_NR_VDIS) * sizeof(long);
-    QEMUSnapshotInfo *sn_tab = NULL;
-    unsigned wlen, rlen;
-    int found = 0;
-    static SheepdogInode inode;
-    unsigned long *vdi_inuse;
-    unsigned int start_nr;
-    uint64_t hval;
-    uint32_t vid;
-
-    vdi_inuse = g_malloc(max);
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        ret = fd;
-        goto out;
-    }
-
-    rlen = max;
-    wlen = 0;
-
-    memset(&req, 0, sizeof(req));
-
-    req.opcode = SD_OP_READ_VDIS;
-    req.data_length = max;
-
-    ret = do_req(fd, s->aio_context, (SheepdogReq *)&req,
-                 vdi_inuse, &wlen, &rlen);
-
-    closesocket(fd);
-    if (ret) {
-        goto out;
-    }
-
-    sn_tab = g_new0(QEMUSnapshotInfo, nr);
-
-    /* calculate a vdi id with hash function */
-    hval = fnv_64a_buf(s->name, strlen(s->name), FNV1A_64_INIT);
-    start_nr = hval & (SD_NR_VDIS - 1);
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        ret = fd;
-        goto out;
-    }
-
-    for (vid = start_nr; found < nr; vid = (vid + 1) % SD_NR_VDIS) {
-        if (!test_bit(vid, vdi_inuse)) {
-            break;
-        }
-
-        /* we don't need to read entire object */
-        ret = read_object(fd, s->aio_context, (char *)&inode,
-                          vid_to_vdi_oid(vid),
-                          0, SD_INODE_SIZE - sizeof(inode.data_vdi_id), 0,
-                          s->cache_flags);
-
-        if (ret) {
-            continue;
-        }
-
-        if (!strcmp(inode.name, s->name) && is_snapshot(&inode)) {
-            sn_tab[found].date_sec = inode.snap_ctime >> 32;
-            sn_tab[found].date_nsec = inode.snap_ctime & 0xffffffff;
-            sn_tab[found].vm_state_size = inode.vm_state_size;
-            sn_tab[found].vm_clock_nsec = inode.vm_clock_nsec;
-
-            snprintf(sn_tab[found].id_str, sizeof(sn_tab[found].id_str),
-                     "%" PRIu32, inode.snap_id);
-            pstrcpy(sn_tab[found].name,
-                    MIN(sizeof(sn_tab[found].name), sizeof(inode.tag)),
-                    inode.tag);
-            found++;
-        }
-    }
-
-    closesocket(fd);
-out:
-    *psn_tab = sn_tab;
-
-    g_free(vdi_inuse);
-
-    if (ret < 0) {
-        return ret;
-    }
-
-    return found;
-}
-
-static int do_load_save_vmstate(BDRVSheepdogState *s, uint8_t *data,
-                                int64_t pos, int size, int load)
-{
-    Error *local_err = NULL;
-    bool create;
-    int fd, ret = 0, remaining = size;
-    unsigned int data_len;
-    uint64_t vmstate_oid;
-    uint64_t offset;
-    uint32_t vdi_index;
-    uint32_t vdi_id = load ? s->inode.parent_vdi_id : s->inode.vdi_id;
-    uint32_t object_size = (UINT32_C(1) << s->inode.block_size_shift);
-
-    fd = connect_to_sdog(s, &local_err);
-    if (fd < 0) {
-        error_report_err(local_err);
-        return fd;
-    }
-
-    while (remaining) {
-        vdi_index = pos / object_size;
-        offset = pos % object_size;
-
-        data_len = MIN(remaining, object_size - offset);
-
-        vmstate_oid = vid_to_vmstate_oid(vdi_id, vdi_index);
-
-        create = (offset == 0);
-        if (load) {
-            ret = read_object(fd, s->aio_context, (char *)data, vmstate_oid,
-                              s->inode.nr_copies, data_len, offset,
-                              s->cache_flags);
-        } else {
-            ret = write_object(fd, s->aio_context, (char *)data, vmstate_oid,
-                               s->inode.nr_copies, data_len, offset, create,
-                               s->cache_flags);
-        }
-
-        if (ret < 0) {
-            error_report("failed to save vmstate %s", strerror(errno));
-            goto cleanup;
-        }
-
-        pos += data_len;
-        data += data_len;
-        remaining -= data_len;
-    }
-    ret = size;
-cleanup:
-    closesocket(fd);
-    return ret;
-}
-
-static int sd_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov,
-                           int64_t pos)
-{
-    BDRVSheepdogState *s = bs->opaque;
-    void *buf;
-    int ret;
-
-    buf = qemu_blockalign(bs, qiov->size);
-    qemu_iovec_to_buf(qiov, 0, buf, qiov->size);
-    ret = do_load_save_vmstate(s, (uint8_t *) buf, pos, qiov->size, 0);
-    qemu_vfree(buf);
-
-    return ret;
-}
-
-static int sd_load_vmstate(BlockDriverState *bs, uint8_t *data,
-                           int64_t pos, int size)
-{
-    BDRVSheepdogState *s = bs->opaque;
-
-    return do_load_save_vmstate(s, data, pos, size, 1);
-}
-
-
-static coroutine_fn int sd_co_discard(BlockDriverState *bs, int64_t sector_num,
-                                      int nb_sectors)
-{
-    SheepdogAIOCB *acb;
-    BDRVSheepdogState *s = bs->opaque;
-    int ret;
-    QEMUIOVector discard_iov;
-    struct iovec iov;
-    uint32_t zero = 0;
-
-    if (!s->discard_supported) {
-            return 0;
-    }
-
-    memset(&discard_iov, 0, sizeof(discard_iov));
-    memset(&iov, 0, sizeof(iov));
-    iov.iov_base = &zero;
-    iov.iov_len = sizeof(zero);
-    discard_iov.iov = &iov;
-    discard_iov.niov = 1;
-    acb = sd_aio_setup(bs, &discard_iov, sector_num, nb_sectors);
-    acb->aiocb_type = AIOCB_DISCARD_OBJ;
-    acb->aio_done_func = sd_finish_aiocb;
-
-retry:
-    if (check_overlapping_aiocb(s, acb)) {
-        qemu_co_queue_wait(&s->overlapping_queue);
-        goto retry;
-    }
-
-    ret = sd_co_rw_vector(acb);
-    if (ret <= 0) {
-        QLIST_REMOVE(acb, aiocb_siblings);
-        qemu_co_queue_restart_all(&s->overlapping_queue);
-        qemu_aio_unref(acb);
-        return ret;
-    }
-
-    qemu_coroutine_yield();
-
-    QLIST_REMOVE(acb, aiocb_siblings);
-    qemu_co_queue_restart_all(&s->overlapping_queue);
-
-    return acb->ret;
-}
-
-static coroutine_fn int64_t
-sd_co_get_block_status(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
-                       int *pnum, BlockDriverState **file)
-{
-    BDRVSheepdogState *s = bs->opaque;
-    SheepdogInode *inode = &s->inode;
-    uint32_t object_size = (UINT32_C(1) << inode->block_size_shift);
-    uint64_t offset = sector_num * BDRV_SECTOR_SIZE;
-    unsigned long start = offset / object_size,
-                  end = DIV_ROUND_UP((sector_num + nb_sectors) *
-                                     BDRV_SECTOR_SIZE, object_size);
-    unsigned long idx;
-    int64_t ret = BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | offset;
-
-    for (idx = start; idx < end; idx++) {
-        if (inode->data_vdi_id[idx] == 0) {
-            break;
-        }
-    }
-    if (idx == start) {
-        /* Get the longest length of unallocated sectors */
-        ret = 0;
-        for (idx = start + 1; idx < end; idx++) {
-            if (inode->data_vdi_id[idx] != 0) {
-                break;
-            }
-        }
-    }
-
-    *pnum = (idx - start) * object_size / BDRV_SECTOR_SIZE;
-    if (*pnum > nb_sectors) {
-        *pnum = nb_sectors;
-    }
-    if (ret > 0 && ret & BDRV_BLOCK_OFFSET_VALID) {
-        *file = bs;
-    }
-    return ret;
-}
-
-static int64_t sd_get_allocated_file_size(BlockDriverState *bs)
-{
-    BDRVSheepdogState *s = bs->opaque;
-    SheepdogInode *inode = &s->inode;
-    uint32_t object_size = (UINT32_C(1) << inode->block_size_shift);
-    unsigned long i, last = DIV_ROUND_UP(inode->vdi_size, object_size);
-    uint64_t size = 0;
-
-    for (i = 0; i < last; i++) {
-        if (inode->data_vdi_id[i] == 0) {
-            continue;
-        }
-        size += object_size;
-    }
-    return size;
-}
-
-static QemuOptsList sd_create_opts = {
-    .name = "sheepdog-create-opts",
-    .head = QTAILQ_HEAD_INITIALIZER(sd_create_opts.head),
-    .desc = {
-        {
-            .name = BLOCK_OPT_SIZE,
-            .type = QEMU_OPT_SIZE,
-            .help = "Virtual disk size"
-        },
-        {
-            .name = BLOCK_OPT_BACKING_FILE,
-            .type = QEMU_OPT_STRING,
-            .help = "File name of a base image"
-        },
-        {
-            .name = BLOCK_OPT_PREALLOC,
-            .type = QEMU_OPT_STRING,
-            .help = "Preallocation mode (allowed values: off, full)"
-        },
-        {
-            .name = BLOCK_OPT_REDUNDANCY,
-            .type = QEMU_OPT_STRING,
-            .help = "Redundancy of the image"
-        },
-        {
-            .name = BLOCK_OPT_OBJECT_SIZE,
-            .type = QEMU_OPT_SIZE,
-            .help = "Object size of the image"
-        },
-        { /* end of list */ }
-    }
-};
-
-static BlockDriver bdrv_sheepdog = {
-    .format_name    = "sheepdog",
-    .protocol_name  = "sheepdog",
-    .instance_size  = sizeof(BDRVSheepdogState),
-    .bdrv_needs_filename = true,
-    .bdrv_file_open = sd_open,
-    .bdrv_reopen_prepare    = sd_reopen_prepare,
-    .bdrv_reopen_commit     = sd_reopen_commit,
-    .bdrv_reopen_abort      = sd_reopen_abort,
-    .bdrv_close     = sd_close,
-    .bdrv_create    = sd_create,
-    .bdrv_has_zero_init = bdrv_has_zero_init_1,
-    .bdrv_getlength = sd_getlength,
-    .bdrv_get_allocated_file_size = sd_get_allocated_file_size,
-    .bdrv_truncate  = sd_truncate,
-
-    .bdrv_co_readv  = sd_co_readv,
-    .bdrv_co_writev = sd_co_writev,
-    .bdrv_co_flush_to_disk  = sd_co_flush_to_disk,
-    .bdrv_co_discard = sd_co_discard,
-    .bdrv_co_get_block_status = sd_co_get_block_status,
-
-    .bdrv_snapshot_create   = sd_snapshot_create,
-    .bdrv_snapshot_goto     = sd_snapshot_goto,
-    .bdrv_snapshot_delete   = sd_snapshot_delete,
-    .bdrv_snapshot_list     = sd_snapshot_list,
-
-    .bdrv_save_vmstate  = sd_save_vmstate,
-    .bdrv_load_vmstate  = sd_load_vmstate,
-
-    .bdrv_detach_aio_context = sd_detach_aio_context,
-    .bdrv_attach_aio_context = sd_attach_aio_context,
-
-    .create_opts    = &sd_create_opts,
-};
-
-static BlockDriver bdrv_sheepdog_tcp = {
-    .format_name    = "sheepdog",
-    .protocol_name  = "sheepdog+tcp",
-    .instance_size  = sizeof(BDRVSheepdogState),
-    .bdrv_needs_filename = true,
-    .bdrv_file_open = sd_open,
-    .bdrv_reopen_prepare    = sd_reopen_prepare,
-    .bdrv_reopen_commit     = sd_reopen_commit,
-    .bdrv_reopen_abort      = sd_reopen_abort,
-    .bdrv_close     = sd_close,
-    .bdrv_create    = sd_create,
-    .bdrv_has_zero_init = bdrv_has_zero_init_1,
-    .bdrv_getlength = sd_getlength,
-    .bdrv_get_allocated_file_size = sd_get_allocated_file_size,
-    .bdrv_truncate  = sd_truncate,
-
-    .bdrv_co_readv  = sd_co_readv,
-    .bdrv_co_writev = sd_co_writev,
-    .bdrv_co_flush_to_disk  = sd_co_flush_to_disk,
-    .bdrv_co_discard = sd_co_discard,
-    .bdrv_co_get_block_status = sd_co_get_block_status,
-
-    .bdrv_snapshot_create   = sd_snapshot_create,
-    .bdrv_snapshot_goto     = sd_snapshot_goto,
-    .bdrv_snapshot_delete   = sd_snapshot_delete,
-    .bdrv_snapshot_list     = sd_snapshot_list,
-
-    .bdrv_save_vmstate  = sd_save_vmstate,
-    .bdrv_load_vmstate  = sd_load_vmstate,
-
-    .bdrv_detach_aio_context = sd_detach_aio_context,
-    .bdrv_attach_aio_context = sd_attach_aio_context,
-
-    .create_opts    = &sd_create_opts,
-};
-
-static BlockDriver bdrv_sheepdog_unix = {
-    .format_name    = "sheepdog",
-    .protocol_name  = "sheepdog+unix",
-    .instance_size  = sizeof(BDRVSheepdogState),
-    .bdrv_needs_filename = true,
-    .bdrv_file_open = sd_open,
-    .bdrv_reopen_prepare    = sd_reopen_prepare,
-    .bdrv_reopen_commit     = sd_reopen_commit,
-    .bdrv_reopen_abort      = sd_reopen_abort,
-    .bdrv_close     = sd_close,
-    .bdrv_create    = sd_create,
-    .bdrv_has_zero_init = bdrv_has_zero_init_1,
-    .bdrv_getlength = sd_getlength,
-    .bdrv_get_allocated_file_size = sd_get_allocated_file_size,
-    .bdrv_truncate  = sd_truncate,
-
-    .bdrv_co_readv  = sd_co_readv,
-    .bdrv_co_writev = sd_co_writev,
-    .bdrv_co_flush_to_disk  = sd_co_flush_to_disk,
-    .bdrv_co_discard = sd_co_discard,
-    .bdrv_co_get_block_status = sd_co_get_block_status,
-
-    .bdrv_snapshot_create   = sd_snapshot_create,
-    .bdrv_snapshot_goto     = sd_snapshot_goto,
-    .bdrv_snapshot_delete   = sd_snapshot_delete,
-    .bdrv_snapshot_list     = sd_snapshot_list,
-
-    .bdrv_save_vmstate  = sd_save_vmstate,
-    .bdrv_load_vmstate  = sd_load_vmstate,
-
-    .bdrv_detach_aio_context = sd_detach_aio_context,
-    .bdrv_attach_aio_context = sd_attach_aio_context,
-
-    .create_opts    = &sd_create_opts,
-};
-
-static void bdrv_sheepdog_init(void)
-{
-    bdrv_register(&bdrv_sheepdog);
-    bdrv_register(&bdrv_sheepdog_tcp);
-    bdrv_register(&bdrv_sheepdog_unix);
-}
-block_init(bdrv_sheepdog_init);