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-rw-r--r--block/nbd-client.c8
-rw-r--r--include/block/nbd.h30
-rw-r--r--nbd/client.c104
-rw-r--r--nbd/trace-events3
4 files changed, 113 insertions, 32 deletions
diff --git a/block/nbd-client.c b/block/nbd-client.c
index c0683c3c83..58493b7ac4 100644
--- a/block/nbd-client.c
+++ b/block/nbd-client.c
@@ -92,7 +92,9 @@ static coroutine_fn void nbd_read_reply_entry(void *opaque)
i = HANDLE_TO_INDEX(s, s->reply.handle);
if (i >= MAX_NBD_REQUESTS ||
!s->requests[i].coroutine ||
- !s->requests[i].receiving) {
+ !s->requests[i].receiving ||
+ nbd_reply_is_structured(&s->reply))
+ {
break;
}
@@ -194,8 +196,8 @@ static int nbd_co_receive_reply(NBDClientSession *s,
ret = -EIO;
} else {
assert(s->reply.handle == handle);
- ret = -s->reply.error;
- if (qiov && s->reply.error == 0) {
+ ret = -nbd_errno_to_system_errno(s->reply.simple.error);
+ if (qiov && ret == 0) {
if (qio_channel_readv_all(s->ioc, qiov->iov, qiov->niov,
NULL) < 0) {
ret = -EIO;
diff --git a/include/block/nbd.h b/include/block/nbd.h
index 225e9575e4..2ee1578420 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -57,12 +57,6 @@ struct NBDRequest {
};
typedef struct NBDRequest NBDRequest;
-struct NBDReply {
- uint64_t handle;
- uint32_t error;
-};
-typedef struct NBDReply NBDReply;
-
typedef struct NBDSimpleReply {
uint32_t magic; /* NBD_SIMPLE_REPLY_MAGIC */
uint32_t error;
@@ -78,6 +72,20 @@ typedef struct NBDStructuredReplyChunk {
uint32_t length; /* length of payload */
} QEMU_PACKED NBDStructuredReplyChunk;
+typedef union NBDReply {
+ NBDSimpleReply simple;
+ NBDStructuredReplyChunk structured;
+ struct {
+ /* @magic and @handle fields have the same offset and size both in
+ * simple reply and structured reply chunk, so let them be accessible
+ * without ".simple." or ".structured." specification
+ */
+ uint32_t magic;
+ uint32_t _skip;
+ uint64_t handle;
+ } QEMU_PACKED;
+} NBDReply;
+
/* Header of NBD_REPLY_TYPE_OFFSET_DATA, complete NBD_REPLY_TYPE_OFFSET_HOLE */
typedef struct NBDStructuredRead {
NBDStructuredReplyChunk h;
@@ -256,4 +264,14 @@ void nbd_client_put(NBDClient *client);
void nbd_server_start(SocketAddress *addr, const char *tls_creds,
Error **errp);
+static inline bool nbd_reply_is_simple(NBDReply *reply)
+{
+ return reply->magic == NBD_SIMPLE_REPLY_MAGIC;
+}
+
+static inline bool nbd_reply_is_structured(NBDReply *reply)
+{
+ return reply->magic == NBD_STRUCTURED_REPLY_MAGIC;
+}
+
#endif
diff --git a/nbd/client.c b/nbd/client.c
index 9acf745b79..4f0745f601 100644
--- a/nbd/client.c
+++ b/nbd/client.c
@@ -908,6 +908,57 @@ int nbd_send_request(QIOChannel *ioc, NBDRequest *request)
return nbd_write(ioc, buf, sizeof(buf), NULL);
}
+/* nbd_receive_simple_reply
+ * Read simple reply except magic field (which should be already read).
+ * Payload is not read (payload is possible for CMD_READ, but here we even
+ * don't know whether it take place or not).
+ */
+static int nbd_receive_simple_reply(QIOChannel *ioc, NBDSimpleReply *reply,
+ Error **errp)
+{
+ int ret;
+
+ assert(reply->magic == NBD_SIMPLE_REPLY_MAGIC);
+
+ ret = nbd_read(ioc, (uint8_t *)reply + sizeof(reply->magic),
+ sizeof(*reply) - sizeof(reply->magic), errp);
+ if (ret < 0) {
+ return ret;
+ }
+
+ be32_to_cpus(&reply->error);
+ be64_to_cpus(&reply->handle);
+
+ return 0;
+}
+
+/* nbd_receive_structured_reply_chunk
+ * Read structured reply chunk except magic field (which should be already
+ * read).
+ * Payload is not read.
+ */
+static int nbd_receive_structured_reply_chunk(QIOChannel *ioc,
+ NBDStructuredReplyChunk *chunk,
+ Error **errp)
+{
+ int ret;
+
+ assert(chunk->magic == NBD_STRUCTURED_REPLY_MAGIC);
+
+ ret = nbd_read(ioc, (uint8_t *)chunk + sizeof(chunk->magic),
+ sizeof(*chunk) - sizeof(chunk->magic), errp);
+ if (ret < 0) {
+ return ret;
+ }
+
+ be16_to_cpus(&chunk->flags);
+ be16_to_cpus(&chunk->type);
+ be64_to_cpus(&chunk->handle);
+ be32_to_cpus(&chunk->length);
+
+ return 0;
+}
+
/* nbd_receive_reply
* Returns 1 on success
* 0 on eof, when no data was read (errp is not set)
@@ -915,38 +966,47 @@ int nbd_send_request(QIOChannel *ioc, NBDRequest *request)
*/
int nbd_receive_reply(QIOChannel *ioc, NBDReply *reply, Error **errp)
{
- uint8_t buf[NBD_REPLY_SIZE];
- uint32_t magic;
int ret;
- ret = nbd_read_eof(ioc, buf, sizeof(buf), errp);
+ ret = nbd_read_eof(ioc, &reply->magic, sizeof(reply->magic), errp);
if (ret <= 0) {
return ret;
}
- /* Reply
- [ 0 .. 3] magic (NBD_SIMPLE_REPLY_MAGIC)
- [ 4 .. 7] error (0 == no error)
- [ 7 .. 15] handle
- */
+ be32_to_cpus(&reply->magic);
- magic = ldl_be_p(buf);
- reply->error = ldl_be_p(buf + 4);
- reply->handle = ldq_be_p(buf + 8);
-
- trace_nbd_receive_reply(magic, reply->error, nbd_err_lookup(reply->error),
- reply->handle);
- reply->error = nbd_errno_to_system_errno(reply->error);
+ switch (reply->magic) {
+ case NBD_SIMPLE_REPLY_MAGIC:
+ ret = nbd_receive_simple_reply(ioc, &reply->simple, errp);
+ if (ret < 0) {
+ break;
+ }
- if (reply->error == ESHUTDOWN) {
- /* This works even on mingw which lacks a native ESHUTDOWN */
- error_setg(errp, "server shutting down");
+ trace_nbd_receive_simple_reply(reply->simple.error,
+ nbd_err_lookup(reply->simple.error),
+ reply->handle);
+ if (reply->simple.error == NBD_ESHUTDOWN) {
+ /* This works even on mingw which lacks a native ESHUTDOWN */
+ error_setg(errp, "server shutting down");
+ return -EINVAL;
+ }
+ break;
+ case NBD_STRUCTURED_REPLY_MAGIC:
+ ret = nbd_receive_structured_reply_chunk(ioc, &reply->structured, errp);
+ if (ret < 0) {
+ break;
+ }
+ trace_nbd_receive_structured_reply_chunk(reply->structured.flags,
+ reply->structured.type,
+ reply->structured.handle,
+ reply->structured.length);
+ break;
+ default:
+ error_setg(errp, "invalid magic (got 0x%" PRIx32 ")", reply->magic);
return -EINVAL;
}
-
- if (magic != NBD_SIMPLE_REPLY_MAGIC) {
- error_setg(errp, "invalid magic (got 0x%" PRIx32 ")", magic);
- return -EINVAL;
+ if (ret < 0) {
+ return ret;
}
return 1;
diff --git a/nbd/trace-events b/nbd/trace-events
index 596df96575..4a13757524 100644
--- a/nbd/trace-events
+++ b/nbd/trace-events
@@ -26,7 +26,8 @@ nbd_client_loop_ret(int ret, const char *error) "NBD loop returned %d: %s"
nbd_client_clear_queue(void) "Clearing NBD queue"
nbd_client_clear_socket(void) "Clearing NBD socket"
nbd_send_request(uint64_t from, uint32_t len, uint64_t handle, uint16_t flags, uint16_t type, const char *name) "Sending request to server: { .from = %" PRIu64", .len = %" PRIu32 ", .handle = %" PRIu64 ", .flags = 0x%" PRIx16 ", .type = %" PRIu16 " (%s) }"
-nbd_receive_reply(uint32_t magic, int32_t error, const char *errname, uint64_t handle) "Got reply: { magic = 0x%" PRIx32 ", .error = %" PRId32 " (%s), handle = %" PRIu64" }"
+nbd_receive_simple_reply(int32_t error, const char *errname, uint64_t handle) "Got simple reply: { .error = %" PRId32 " (%s), handle = %" PRIu64" }"
+nbd_receive_structured_reply_chunk(uint16_t flags, uint16_t type, uint64_t handle, uint32_t length) "Got structured reply chunk: { flags = 0x%" PRIx16 ", type = %d, handle = %" PRIu64 ", length = %" PRIu32 " }"
# nbd/common.c
nbd_unknown_error(int err) "Squashing unexpected error %d to EINVAL"
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-20 06:20:05 +0000