+#include "qemu/main-loop.h"
+
+#include "qapi/qapi-visit-sockets.h"
+#include "qapi/qmp/qstring.h"
+
+#include "block/qdict.h"
+#include "block/nbd.h"
+#include "block/block_int.h"
+
+#define EN_OPTSTR ":exportname="
+#define MAX_NBD_REQUESTS 16
+
+#define HANDLE_TO_INDEX(bs, handle) ((handle) ^ (uint64_t)(intptr_t)(bs))
+#define INDEX_TO_HANDLE(bs, index) ((index) ^ (uint64_t)(intptr_t)(bs))
+
+typedef struct {
+ Coroutine *coroutine;
+ uint64_t offset; /* original offset of the request */
+ bool receiving; /* waiting for connection_co? */
+} NBDClientRequest;
+
+typedef enum NBDClientState {
+ NBD_CLIENT_CONNECTED,
+ NBD_CLIENT_QUIT
+} NBDClientState;
+
+typedef struct BDRVNBDState {
+ QIOChannelSocket *sioc; /* The master data channel */
+ QIOChannel *ioc; /* The current I/O channel which may differ (eg TLS) */
+ NBDExportInfo info;
+
+ CoMutex send_mutex;
+ CoQueue free_sema;
+ Coroutine *connection_co;
+ int in_flight;
+ NBDClientState state;
+
+ NBDClientRequest requests[MAX_NBD_REQUESTS];
+ NBDReply reply;
+ BlockDriverState *bs;
+
+ /* Connection parameters */
+ uint32_t reconnect_delay;
+ SocketAddress *saddr;
+ char *export, *tlscredsid;
+ QCryptoTLSCreds *tlscreds;
+ const char *hostname;
+ char *x_dirty_bitmap;
+} BDRVNBDState;
+
+/* @ret will be used for reconnect in future */
+static void nbd_channel_error(BDRVNBDState *s, int ret)
+{
+ s->state = NBD_CLIENT_QUIT;
+}
+
+static void nbd_recv_coroutines_wake_all(BDRVNBDState *s)
+{
+ int i;
+
+ for (i = 0; i < MAX_NBD_REQUESTS; i++) {
+ NBDClientRequest *req = &s->requests[i];
+
+ if (req->coroutine && req->receiving) {
+ aio_co_wake(req->coroutine);
+ }
+ }
+}
+
+static void nbd_client_detach_aio_context(BlockDriverState *bs)
+{
+ BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
+
+ qio_channel_detach_aio_context(QIO_CHANNEL(s->ioc));
+}
+
+static void nbd_client_attach_aio_context_bh(void *opaque)
+{
+ BlockDriverState *bs = opaque;
+ BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
+
+ /*
+ * The node is still drained, so we know the coroutine has yielded in
+ * nbd_read_eof(), the only place where bs->in_flight can reach 0, or it is
+ * entered for the first time. Both places are safe for entering the
+ * coroutine.
+ */
+ qemu_aio_coroutine_enter(bs->aio_context, s->connection_co);
+ bdrv_dec_in_flight(bs);
+}
+
+static void nbd_client_attach_aio_context(BlockDriverState *bs,
+ AioContext *new_context)
+{
+ BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
+
+ qio_channel_attach_aio_context(QIO_CHANNEL(s->ioc), new_context);
+
+ bdrv_inc_in_flight(bs);
+
+ /*
+ * Need to wait here for the BH to run because the BH must run while the
+ * node is still drained.
+ */
+ aio_wait_bh_oneshot(new_context, nbd_client_attach_aio_context_bh, bs);
+}
+
+
+static void nbd_teardown_connection(BlockDriverState *bs)
+{
+ BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
+
+ assert(s->ioc);
+
+ /* finish any pending coroutines */
+ qio_channel_shutdown(s->ioc,
+ QIO_CHANNEL_SHUTDOWN_BOTH,
+ NULL);
+ BDRV_POLL_WHILE(bs, s->connection_co);
+
+ nbd_client_detach_aio_context(bs);
+ object_unref(OBJECT(s->sioc));
+ s->sioc = NULL;
+ object_unref(OBJECT(s->ioc));
+ s->ioc = NULL;
+}
+
+static coroutine_fn void nbd_connection_entry(void *opaque)
+{
+ BDRVNBDState *s = opaque;
+ uint64_t i;
+ int ret = 0;
+ Error *local_err = NULL;
+
+ while (s->state != NBD_CLIENT_QUIT) {
+ /*
+ * The NBD client can only really be considered idle when it has
+ * yielded from qio_channel_readv_all_eof(), waiting for data. This is
+ * the point where the additional scheduled coroutine entry happens
+ * after nbd_client_attach_aio_context().
+ *
+ * Therefore we keep an additional in_flight reference all the time and
+ * only drop it temporarily here.
+ */
+ assert(s->reply.handle == 0);
+ ret = nbd_receive_reply(s->bs, s->ioc, &s->reply, &local_err);
+
+ if (local_err) {
+ trace_nbd_read_reply_entry_fail(ret, error_get_pretty(local_err));
+ error_free(local_err);
+ }
+ if (ret <= 0) {
+ nbd_channel_error(s, ret ? ret : -EIO);
+ break;
+ }
+
+ /*
+ * There's no need for a mutex on the receive side, because the
+ * handler acts as a synchronization point and ensures that only
+ * one coroutine is called until the reply finishes.
+ */
+ i = HANDLE_TO_INDEX(s, s->reply.handle);
+ if (i >= MAX_NBD_REQUESTS ||
+ !s->requests[i].coroutine ||
+ !s->requests[i].receiving ||
+ (nbd_reply_is_structured(&s->reply) && !s->info.structured_reply))
+ {
+ nbd_channel_error(s, -EINVAL);
+ break;
+ }
+
+ /*
+ * We're woken up again by the request itself. Note that there
+ * is no race between yielding and reentering connection_co. This
+ * is because:
+ *
+ * - if the request runs on the same AioContext, it is only
+ * entered after we yield
+ *
+ * - if the request runs on a different AioContext, reentering
+ * connection_co happens through a bottom half, which can only
+ * run after we yield.
+ */
+ aio_co_wake(s->requests[i].coroutine);
+ qemu_coroutine_yield();
+ }
+
+ nbd_recv_coroutines_wake_all(s);
+ bdrv_dec_in_flight(s->bs);
+
+ s->connection_co = NULL;
+ aio_wait_kick();
+}
+
+static int nbd_co_send_request(BlockDriverState *bs,
+ NBDRequest *request,
+ QEMUIOVector *qiov)
+{
+ BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
+ int rc, i = -1;
+
+ qemu_co_mutex_lock(&s->send_mutex);
+ while (s->in_flight == MAX_NBD_REQUESTS) {
+ qemu_co_queue_wait(&s->free_sema, &s->send_mutex);
+ }
+
+ if (s->state != NBD_CLIENT_CONNECTED) {
+ rc = -EIO;
+ goto err;
+ }
+
+ s->in_flight++;
+
+ for (i = 0; i < MAX_NBD_REQUESTS; i++) {
+ if (s->requests[i].coroutine == NULL) {
+ break;
+ }
+ }
+
+ g_assert(qemu_in_coroutine());
+ assert(i < MAX_NBD_REQUESTS);
+
+ s->requests[i].coroutine = qemu_coroutine_self();
+ s->requests[i].offset = request->from;
+ s->requests[i].receiving = false;
+
+ request->handle = INDEX_TO_HANDLE(s, i);
+
+ assert(s->ioc);
+
+ if (qiov) {
+ qio_channel_set_cork(s->ioc, true);
+ rc = nbd_send_request(s->ioc, request);
+ if (rc >= 0 && s->state == NBD_CLIENT_CONNECTED) {
+ if (qio_channel_writev_all(s->ioc, qiov->iov, qiov->niov,
+ NULL) < 0) {
+ rc = -EIO;
+ }
+ } else if (rc >= 0) {
+ rc = -EIO;
+ }
+ qio_channel_set_cork(s->ioc, false);
+ } else {
+ rc = nbd_send_request(s->ioc, request);
+ }
+
+err:
+ if (rc < 0) {
+ nbd_channel_error(s, rc);
+ if (i != -1) {
+ s->requests[i].coroutine = NULL;
+ s->in_flight--;
+ }
+ qemu_co_queue_next(&s->free_sema);
+ }
+ qemu_co_mutex_unlock(&s->send_mutex);
+ return rc;
+}
+
+static inline uint16_t payload_advance16(uint8_t **payload)
+{
+ *payload += 2;
+ return lduw_be_p(*payload - 2);
+}
+
+static inline uint32_t payload_advance32(uint8_t **payload)
+{
+ *payload += 4;
+ return ldl_be_p(*payload - 4);
+}
+
+static inline uint64_t payload_advance64(uint8_t **payload)
+{
+ *payload += 8;
+ return ldq_be_p(*payload - 8);
+}
+
+static int nbd_parse_offset_hole_payload(BDRVNBDState *s,
+ NBDStructuredReplyChunk *chunk,
+ uint8_t *payload, uint64_t orig_offset,
+ QEMUIOVector *qiov, Error **errp)
+{
+ uint64_t offset;
+ uint32_t hole_size;
+
+ if (chunk->length != sizeof(offset) + sizeof(hole_size)) {
+ error_setg(errp, "Protocol error: invalid payload for "
+ "NBD_REPLY_TYPE_OFFSET_HOLE");
+ return -EINVAL;
+ }
+
+ offset = payload_advance64(&payload);
+ hole_size = payload_advance32(&payload);
+
+ if (!hole_size || offset < orig_offset || hole_size > qiov->size ||
+ offset > orig_offset + qiov->size - hole_size) {
+ error_setg(errp, "Protocol error: server sent chunk exceeding requested"
+ " region");
+ return -EINVAL;
+ }
+ if (s->info.min_block &&
+ !QEMU_IS_ALIGNED(hole_size, s->info.min_block)) {
+ trace_nbd_structured_read_compliance("hole");
+ }
+
+ qemu_iovec_memset(qiov, offset - orig_offset, 0, hole_size);
+
+ return 0;
+}
+
+/*
+ * nbd_parse_blockstatus_payload
+ * Based on our request, we expect only one extent in reply, for the
+ * base:allocation context.
+ */
+static int nbd_parse_blockstatus_payload(BDRVNBDState *s,
+ NBDStructuredReplyChunk *chunk,
+ uint8_t *payload, uint64_t orig_length,
+ NBDExtent *extent, Error **errp)
+{
+ uint32_t context_id;
+
+ /* The server succeeded, so it must have sent [at least] one extent */
+ if (chunk->length < sizeof(context_id) + sizeof(*extent)) {
+ error_setg(errp, "Protocol error: invalid payload for "
+ "NBD_REPLY_TYPE_BLOCK_STATUS");
+ return -EINVAL;
+ }
+
+ context_id = payload_advance32(&payload);
+ if (s->info.context_id != context_id) {
+ error_setg(errp, "Protocol error: unexpected context id %d for "
+ "NBD_REPLY_TYPE_BLOCK_STATUS, when negotiated context "
+ "id is %d", context_id,
+ s->info.context_id);
+ return -EINVAL;
+ }
+
+ extent->length = payload_advance32(&payload);
+ extent->flags = payload_advance32(&payload);
+
+ if (extent->length == 0) {
+ error_setg(errp, "Protocol error: server sent status chunk with "
+ "zero length");
+ return -EINVAL;
+ }
+
+ /*
+ * A server sending unaligned block status is in violation of the
+ * protocol, but as qemu-nbd 3.1 is such a server (at least for
+ * POSIX files that are not a multiple of 512 bytes, since qemu
+ * rounds files up to 512-byte multiples but lseek(SEEK_HOLE)
+ * still sees an implicit hole beyond the real EOF), it's nicer to
+ * work around the misbehaving server. If the request included
+ * more than the final unaligned block, truncate it back to an
+ * aligned result; if the request was only the final block, round
+ * up to the full block and change the status to fully-allocated
+ * (always a safe status, even if it loses information).
+ */
+ if (s->info.min_block && !QEMU_IS_ALIGNED(extent->length,
+ s->info.min_block)) {
+ trace_nbd_parse_blockstatus_compliance("extent length is unaligned");
+ if (extent->length > s->info.min_block) {
+ extent->length = QEMU_ALIGN_DOWN(extent->length,
+ s->info.min_block);
+ } else {
+ extent->length = s->info.min_block;
+ extent->flags = 0;
+ }
+ }
+
+ /*
+ * We used NBD_CMD_FLAG_REQ_ONE, so the server should not have
+ * sent us any more than one extent, nor should it have included
+ * status beyond our request in that extent. However, it's easy
+ * enough to ignore the server's noncompliance without killing the
+ * connection; just ignore trailing extents, and clamp things to
+ * the length of our request.
+ */
+ if (chunk->length > sizeof(context_id) + sizeof(*extent)) {
+ trace_nbd_parse_blockstatus_compliance("more than one extent");
+ }
+ if (extent->length > orig_length) {
+ extent->length = orig_length;
+ trace_nbd_parse_blockstatus_compliance("extent length too large");
+ }
+
+ return 0;
+}
+
+/*
+ * nbd_parse_error_payload
+ * on success @errp contains message describing nbd error reply
+ */
+static int nbd_parse_error_payload(NBDStructuredReplyChunk *chunk,
+ uint8_t *payload, int *request_ret,
+ Error **errp)
+{
+ uint32_t error;
+ uint16_t message_size;
+
+ assert(chunk->type & (1 << 15));
+
+ if (chunk->length < sizeof(error) + sizeof(message_size)) {
+ error_setg(errp,
+ "Protocol error: invalid payload for structured error");
+ return -EINVAL;
+ }
+
+ error = nbd_errno_to_system_errno(payload_advance32(&payload));
+ if (error == 0) {
+ error_setg(errp, "Protocol error: server sent structured error chunk "
+ "with error = 0");
+ return -EINVAL;
+ }
+
+ *request_ret = -error;
+ message_size = payload_advance16(&payload);
+
+ if (message_size > chunk->length - sizeof(error) - sizeof(message_size)) {
+ error_setg(errp, "Protocol error: server sent structured error chunk "
+ "with incorrect message size");
+ return -EINVAL;
+ }
+
+ /* TODO: Add a trace point to mention the server complaint */
+
+ /* TODO handle ERROR_OFFSET */
+
+ return 0;
+}
+
+static int nbd_co_receive_offset_data_payload(BDRVNBDState *s,
+ uint64_t orig_offset,
+ QEMUIOVector *qiov, Error **errp)
+{
+ QEMUIOVector sub_qiov;
+ uint64_t offset;
+ size_t data_size;
+ int ret;
+ NBDStructuredReplyChunk *chunk = &s->reply.structured;
+
+ assert(nbd_reply_is_structured(&s->reply));
+
+ /* The NBD spec requires at least one byte of payload */
+ if (chunk->length <= sizeof(offset)) {
+ error_setg(errp, "Protocol error: invalid payload for "
+ "NBD_REPLY_TYPE_OFFSET_DATA");
+ return -EINVAL;
+ }
+
+ if (nbd_read64(s->ioc, &offset, "OFFSET_DATA offset", errp) < 0) {
+ return -EIO;
+ }
+
+ data_size = chunk->length - sizeof(offset);
+ assert(data_size);
+ if (offset < orig_offset || data_size > qiov->size ||
+ offset > orig_offset + qiov->size - data_size) {
+ error_setg(errp, "Protocol error: server sent chunk exceeding requested"
+ " region");
+ return -EINVAL;
+ }
+ if (s->info.min_block && !QEMU_IS_ALIGNED(data_size, s->info.min_block)) {
+ trace_nbd_structured_read_compliance("data");
+ }
+
+ qemu_iovec_init(&sub_qiov, qiov->niov);
+ qemu_iovec_concat(&sub_qiov, qiov, offset - orig_offset, data_size);
+ ret = qio_channel_readv_all(s->ioc, sub_qiov.iov, sub_qiov.niov, errp);
+ qemu_iovec_destroy(&sub_qiov);
+
+ return ret < 0 ? -EIO : 0;
+}
+
+#define NBD_MAX_MALLOC_PAYLOAD 1000
+static coroutine_fn int nbd_co_receive_structured_payload(
+ BDRVNBDState *s, void **payload, Error **errp)
+{
+ int ret;
+ uint32_t len;
+
+ assert(nbd_reply_is_structured(&s->reply));
+
+ len = s->reply.structured.length;
+
+ if (len == 0) {
+ return 0;
+ }
+
+ if (payload == NULL) {
+ error_setg(errp, "Unexpected structured payload");
+ return -EINVAL;
+ }
+
+ if (len > NBD_MAX_MALLOC_PAYLOAD) {
+ error_setg(errp, "Payload too large");
+ return -EINVAL;
+ }
+
+ *payload = g_new(char, len);
+ ret = nbd_read(s->ioc, *payload, len, "structured payload", errp);
+ if (ret < 0) {
+ g_free(*payload);
+ *payload = NULL;
+ return ret;
+ }
+
+ return 0;
+}
+
+/*
+ * nbd_co_do_receive_one_chunk
+ * for simple reply:
+ * set request_ret to received reply error
+ * if qiov is not NULL: read payload to @qiov
+ * for structured reply chunk:
+ * if error chunk: read payload, set @request_ret, do not set @payload
+ * else if offset_data chunk: read payload data to @qiov, do not set @payload
+ * else: read payload to @payload
+ *
+ * If function fails, @errp contains corresponding error message, and the
+ * connection with the server is suspect. If it returns 0, then the
+ * transaction succeeded (although @request_ret may be a negative errno
+ * corresponding to the server's error reply), and errp is unchanged.
+ */
+static coroutine_fn int nbd_co_do_receive_one_chunk(
+ BDRVNBDState *s, uint64_t handle, bool only_structured,
+ int *request_ret, QEMUIOVector *qiov, void **payload, Error **errp)
+{
+ int ret;
+ int i = HANDLE_TO_INDEX(s, handle);
+ void *local_payload = NULL;
+ NBDStructuredReplyChunk *chunk;
+
+ if (payload) {
+ *payload = NULL;
+ }
+ *request_ret = 0;
+
+ /* Wait until we're woken up by nbd_connection_entry. */
+ s->requests[i].receiving = true;
+ qemu_coroutine_yield();
+ s->requests[i].receiving = false;
+ if (s->state != NBD_CLIENT_CONNECTED) {
+ error_setg(errp, "Connection closed");
+ return -EIO;
+ }
+ assert(s->ioc);
+
+ assert(s->reply.handle == handle);
+
+ if (nbd_reply_is_simple(&s->reply)) {
+ if (only_structured) {
+ error_setg(errp, "Protocol error: simple reply when structured "
+ "reply chunk was expected");
+ return -EINVAL;
+ }
+
+ *request_ret = -nbd_errno_to_system_errno(s->reply.simple.error);
+ if (*request_ret < 0 || !qiov) {
+ return 0;
+ }
+
+ return qio_channel_readv_all(s->ioc, qiov->iov, qiov->niov,
+ errp) < 0 ? -EIO : 0;
+ }
+
+ /* handle structured reply chunk */
+ assert(s->info.structured_reply);
+ chunk = &s->reply.structured;
+
+ if (chunk->type == NBD_REPLY_TYPE_NONE) {
+ if (!(chunk->flags & NBD_REPLY_FLAG_DONE)) {
+ error_setg(errp, "Protocol error: NBD_REPLY_TYPE_NONE chunk without"
+ " NBD_REPLY_FLAG_DONE flag set");
+ return -EINVAL;
+ }
+ if (chunk->length) {
+ error_setg(errp, "Protocol error: NBD_REPLY_TYPE_NONE chunk with"
+ " nonzero length");
+ return -EINVAL;
+ }
+ return 0;
+ }
+
+ if (chunk->type == NBD_REPLY_TYPE_OFFSET_DATA) {
+ if (!qiov) {
+ error_setg(errp, "Unexpected NBD_REPLY_TYPE_OFFSET_DATA chunk");
+ return -EINVAL;
+ }
+
+ return nbd_co_receive_offset_data_payload(s, s->requests[i].offset,
+ qiov, errp);
+ }
+
+ if (nbd_reply_type_is_error(chunk->type)) {
+ payload = &local_payload;
+ }
+
+ ret = nbd_co_receive_structured_payload(s, payload, errp);
+ if (ret < 0) {
+ return ret;
+ }
+
+ if (nbd_reply_type_is_error(chunk->type)) {
+ ret = nbd_parse_error_payload(chunk, local_payload, request_ret, errp);
+ g_free(local_payload);
+ return ret;
+ }
+
+ return 0;
+}
+
+/*
+ * nbd_co_receive_one_chunk
+ * Read reply, wake up connection_co and set s->quit if needed.
+ * Return value is a fatal error code or normal nbd reply error code
+ */
+static coroutine_fn int nbd_co_receive_one_chunk(
+ BDRVNBDState *s, uint64_t handle, bool only_structured,
+ int *request_ret, QEMUIOVector *qiov, NBDReply *reply, void **payload,
+ Error **errp)
+{
+ int ret = nbd_co_do_receive_one_chunk(s, handle, only_structured,
+ request_ret, qiov, payload, errp);
+
+ if (ret < 0) {
+ memset(reply, 0, sizeof(*reply));
+ nbd_channel_error(s, ret);
+ } else {
+ /* For assert at loop start in nbd_connection_entry */
+ *reply = s->reply;
+ s->reply.handle = 0;
+ }
+
+ if (s->connection_co) {
+ aio_co_wake(s->connection_co);
+ }
+
+ return ret;
+}
+
+typedef struct NBDReplyChunkIter {
+ int ret;
+ int request_ret;
+ Error *err;
+ bool done, only_structured;
+} NBDReplyChunkIter;
+
+static void nbd_iter_channel_error(NBDReplyChunkIter *iter,
+ int ret, Error **local_err)
+{
+ assert(ret < 0);
+
+ if (!iter->ret) {
+ iter->ret = ret;
+ error_propagate(&iter->err, *local_err);
+ } else {
+ error_free(*local_err);
+ }
+
+ *local_err = NULL;
+}
+
+static void nbd_iter_request_error(NBDReplyChunkIter *iter, int ret)
+{
+ assert(ret < 0);
+
+ if (!iter->request_ret) {
+ iter->request_ret = ret;
+ }
+}
+
+/*
+ * NBD_FOREACH_REPLY_CHUNK
+ * The pointer stored in @payload requires g_free() to free it.
+ */
+#define NBD_FOREACH_REPLY_CHUNK(s, iter, handle, structured, \
+ qiov, reply, payload) \
+ for (iter = (NBDReplyChunkIter) { .only_structured = structured }; \
+ nbd_reply_chunk_iter_receive(s, &iter, handle, qiov, reply, payload);)
+
+/*
+ * nbd_reply_chunk_iter_receive
+ * The pointer stored in @payload requires g_free() to free it.
+ */
+static bool nbd_reply_chunk_iter_receive(BDRVNBDState *s,
+ NBDReplyChunkIter *iter,
+ uint64_t handle,
+ QEMUIOVector *qiov, NBDReply *reply,
+ void **payload)
+{
+ int ret, request_ret;
+ NBDReply local_reply;
+ NBDStructuredReplyChunk *chunk;
+ Error *local_err = NULL;
+ if (s->state != NBD_CLIENT_CONNECTED) {
+ error_setg(&local_err, "Connection closed");
+ nbd_iter_channel_error(iter, -EIO, &local_err);
+ goto break_loop;
+ }
+
+ if (iter->done) {
+ /* Previous iteration was last. */
+ goto break_loop;
+ }
+
+ if (reply == NULL) {
+ reply = &local_reply;
+ }
+
+ ret = nbd_co_receive_one_chunk(s, handle, iter->only_structured,
+ &request_ret, qiov, reply, payload,
+ &local_err);
+ if (ret < 0) {
+ nbd_iter_channel_error(iter, ret, &local_err);
+ } else if (request_ret < 0) {
+ nbd_iter_request_error(iter, request_ret);
+ }
+
+ /* Do not execute the body of NBD_FOREACH_REPLY_CHUNK for simple reply. */
+ if (nbd_reply_is_simple(reply) || s->state != NBD_CLIENT_CONNECTED) {
+ goto break_loop;
+ }
+
+ chunk = &reply->structured;
+ iter->only_structured = true;
+
+ if (chunk->type == NBD_REPLY_TYPE_NONE) {
+ /* NBD_REPLY_FLAG_DONE is already checked in nbd_co_receive_one_chunk */
+ assert(chunk->flags & NBD_REPLY_FLAG_DONE);
+ goto break_loop;
+ }
+
+ if (chunk->flags & NBD_REPLY_FLAG_DONE) {
+ /* This iteration is last. */
+ iter->done = true;
+ }
+
+ /* Execute the loop body */
+ return true;
+
+break_loop:
+ s->requests[HANDLE_TO_INDEX(s, handle)].coroutine = NULL;
+
+ qemu_co_mutex_lock(&s->send_mutex);
+ s->in_flight--;
+ qemu_co_queue_next(&s->free_sema);
+ qemu_co_mutex_unlock(&s->send_mutex);
+
+ return false;
+}
+
+static int nbd_co_receive_return_code(BDRVNBDState *s, uint64_t handle,
+ int *request_ret, Error **errp)
+{
+ NBDReplyChunkIter iter;
+
+ NBD_FOREACH_REPLY_CHUNK(s, iter, handle, false, NULL, NULL, NULL) {
+ /* nbd_reply_chunk_iter_receive does all the work */
+ }
+
+ error_propagate(errp, iter.err);
+ *request_ret = iter.request_ret;
+ return iter.ret;
+}
projects / qemu.git / blobdiff