diff --git a/block/nbd.c b/block/nbd.c index 2f483cddde..097b4188e5 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -407,6 +407,34 @@ static int nbd_co_writev(BlockDriverState *bs, int64_t sector_num, return nbd_co_writev_1(bs, sector_num, nb_sectors, qiov, offset); } +static int nbd_co_flush(BlockDriverState *bs) +{ + BDRVNBDState *s = bs->opaque; + struct nbd_request request; + struct nbd_reply reply; + + if (!(s->nbdflags & NBD_FLAG_SEND_FLUSH)) { + return 0; + } + + request.type = NBD_CMD_FLUSH; + if (s->nbdflags & NBD_FLAG_SEND_FUA) { + request.type |= NBD_CMD_FLAG_FUA; + } + + request.from = 0; + request.len = 0; + + nbd_coroutine_start(s, &request); + if (nbd_co_send_request(s, &request, NULL, 0) == -1) { + reply.error = errno; + } else { + nbd_co_receive_reply(s, &request, &reply, NULL, 0); + } + nbd_coroutine_end(s, &request); + return -reply.error; +} + static void nbd_close(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; @@ -424,14 +452,15 @@ static int64_t nbd_getlength(BlockDriverState *bs) } static BlockDriver bdrv_nbd = { - .format_name = "nbd", - .instance_size = sizeof(BDRVNBDState), - .bdrv_file_open = nbd_open, - .bdrv_co_readv = nbd_co_readv, - .bdrv_co_writev = nbd_co_writev, - .bdrv_close = nbd_close, - .bdrv_getlength = nbd_getlength, - .protocol_name = "nbd", + .format_name = "nbd", + .instance_size = sizeof(BDRVNBDState), + .bdrv_file_open = nbd_open, + .bdrv_co_readv = nbd_co_readv, + .bdrv_co_writev = nbd_co_writev, + .bdrv_close = nbd_close, + .bdrv_co_flush_to_os = nbd_co_flush, + .bdrv_getlength = nbd_getlength, + .protocol_name = "nbd", }; static void bdrv_nbd_init(void) diff --git a/nbd.c b/nbd.c index c597d4733f..4fd0f4ed28 100644 --- a/nbd.c +++ b/nbd.c @@ -203,7 +203,8 @@ int nbd_negotiate(int csock, off_t size, uint32_t flags) cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL); cpu_to_be64w((uint64_t*)(buf + 16), size); cpu_to_be32w((uint32_t*)(buf + 24), - flags | NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_FUA); + flags | NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_FLUSH | + NBD_FLAG_SEND_FUA); memset(buf + 28, 0, 124); if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { @@ -710,6 +711,18 @@ int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset, TRACE("Request type is DISCONNECT"); errno = 0; return 1; + case NBD_CMD_FLUSH: + TRACE("Request type is FLUSH"); + + ret = bdrv_flush(bs); + if (ret < 0) { + LOG("flush failed"); + reply.error = -ret; + } + + if (nbd_send_reply(csock, &reply) == -1) + return -1; + break; default: LOG("invalid request type (%u) received", request.type); errno = EINVAL;