Minimal implementation: for structured error only error_report error
message.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
---
include/block/nbd.h | 6 +
block/nbd-client.c | 358 ++++++++++++++++++++++++++++++++++++++++++++++++----
nbd/client.c | 7 +
3 files changed, 343 insertions(+), 28 deletions(-)
diff --git a/include/block/nbd.h b/include/block/nbd.h
index 1ef8c8897f..e3350b67a4 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -203,6 +203,11 @@ enum {
#define NBD_SREP_TYPE_ERROR NBD_SREP_ERR(1)
#define NBD_SREP_TYPE_ERROR_OFFSET NBD_SREP_ERR(2)
+static inline bool nbd_srep_type_is_error(int type)
+{
+ return type & (1 << 15);
+}
+
/* NBD errors are based on errno numbers, so there is a 1:1 mapping,
* but only a limited set of errno values is specified in the protocol.
* Everything else is squashed to EINVAL.
@@ -241,6 +246,7 @@ static inline int nbd_errno_to_system_errno(int err)
struct NBDExportInfo {
/* Set by client before nbd_receive_negotiate() */
bool request_sizes;
+ bool structured_reply;
/* Set by server results during nbd_receive_negotiate() */
uint64_t size;
uint16_t flags;
diff --git a/block/nbd-client.c b/block/nbd-client.c
index 58493b7ac4..eda78130a2 100644
--- a/block/nbd-client.c
+++ b/block/nbd-client.c
@@ -29,6 +29,7 @@
#include "qemu/osdep.h"
#include "qapi/error.h"
+#include "qemu/error-report.h"
#include "nbd-client.h"
#define HANDLE_TO_INDEX(bs, handle) ((handle) ^ (uint64_t)(intptr_t)(bs))
@@ -93,7 +94,7 @@ static coroutine_fn void nbd_read_reply_entry(void *opaque)
if (i >= MAX_NBD_REQUESTS ||
!s->requests[i].coroutine ||
!s->requests[i].receiving ||
- nbd_reply_is_structured(&s->reply))
+ (nbd_reply_is_structured(&s->reply) && !s->info.structured_reply))
{
break;
}
@@ -181,41 +182,336 @@ err:
return rc;
}
-static int nbd_co_receive_reply(NBDClientSession *s,
- uint64_t handle,
- QEMUIOVector *qiov)
+static inline void payload_advance16(uint8_t **payload, uint16_t **ptr)
+{
+ *ptr = (uint16_t *)*payload;
+ be16_to_cpus(*ptr);
+ *payload += sizeof(**ptr);
+}
+
+static inline void payload_advance32(uint8_t **payload, uint32_t **ptr)
+{
+ *ptr = (uint32_t *)*payload;
+ be32_to_cpus(*ptr);
+ *payload += sizeof(**ptr);
+}
+
+static inline void payload_advance64(uint8_t **payload, uint64_t **ptr)
+{
+ *ptr = (uint64_t *)*payload;
+ be64_to_cpus(*ptr);
+ *payload += sizeof(**ptr);
+}
+
+static int nbd_parse_offset_hole_payload(NBDStructuredReplyChunk *chunk,
+ uint8_t *payload, QEMUIOVector *qiov)
+{
+ uint64_t *offset;
+ uint32_t *hole_size;
+
+ if (chunk->length != sizeof(*offset) + sizeof(*hole_size)) {
+ return -EINVAL;
+ }
+
+ payload_advance64(&payload, &offset);
+ payload_advance32(&payload, &hole_size);
+
+ if (*offset + *hole_size > qiov->size) {
+ return -EINVAL;
+ }
+
+ qemu_iovec_memset(qiov, *offset, 0, *hole_size);
+
+ return 0;
+}
+
+static int nbd_parse_error_payload(NBDStructuredReplyChunk *chunk,
+ uint8_t *payload, int *request_ret)
+{
+ uint32_t *error;
+ uint16_t *message_size;
+
+ assert(chunk->type & (1 << 15));
+
+ if (chunk->length < sizeof(error) + sizeof(message_size)) {
+ return -EINVAL;
+ }
+
+ payload_advance32(&payload, &error);
+ payload_advance16(&payload, &message_size);
+
+ error_report("%.*s", *message_size, payload);
+
+ /* TODO add special case for ERROR_OFFSET */
+
+ *request_ret = nbd_errno_to_system_errno(*error);
+
+ return 0;
+}
+
+static int nbd_co_receive_offset_data_payload(NBDClientSession *s,
+ QEMUIOVector *qiov)
+{
+ QEMUIOVector sub_qiov;
+ uint64_t offset;
+ size_t data_size;
+ int ret;
+ NBDStructuredReplyChunk *chunk = &s->reply.structured;
+
+ assert(nbd_reply_is_structured(&s->reply));
+
+ if (chunk->length < sizeof(offset)) {
+ return -EINVAL;
+ }
+
+ if (nbd_read(s->ioc, &offset, sizeof(offset), NULL) < 0) {
+ return -EIO;
+ }
+ be64_to_cpus(&offset);
+
+ data_size = chunk->length - sizeof(offset);
+ if (offset + data_size > qiov->size) {
+ return -EINVAL;
+ }
+
+ qemu_iovec_init(&sub_qiov, qiov->niov);
+ qemu_iovec_concat(&sub_qiov, qiov, offset, data_size);
+ ret = qio_channel_readv_all(s->ioc, sub_qiov.iov, sub_qiov.niov, NULL);
+ qemu_iovec_destroy(&sub_qiov);
+
+ return ret < 0 ? -EIO : 0;
+}
+
+#define NBD_MAX_MALLOC_PAYLOAD 1000
+static int nbd_co_receive_structured_payload(NBDClientSession *s,
+ void **payload)
+{
+ 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) {
+ return -EINVAL;
+ }
+
+ if (len > NBD_MAX_MALLOC_PAYLOAD) {
+ return -EINVAL;
+ }
+
+ *payload = qemu_memalign(8, len);
+ ret = nbd_read(s->ioc, *payload, len, NULL);
+ if (ret < 0) {
+ qemu_vfree(*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
+ */
+static int nbd_co_do_receive_one_chunk(NBDClientSession *s, uint64_t handle,
+ bool only_structured, int *request_ret,
+ QEMUIOVector *qiov, void **payload)
{
int ret;
int i = HANDLE_TO_INDEX(s, handle);
+ void *local_payload = NULL;
+
+ if (payload) {
+ *payload = NULL;
+ }
+ *request_ret = 0;
/* Wait until we're woken up by nbd_read_reply_entry. */
s->requests[i].receiving = true;
qemu_coroutine_yield();
s->requests[i].receiving = false;
if (!s->ioc || s->quit) {
- ret = -EIO;
- } else {
- assert(s->reply.handle == handle);
- 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;
- s->quit = true;
- }
+ return -EIO;
+ }
+
+ assert(s->reply.handle == handle);
+
+ if (nbd_reply_is_simple(&s->reply)) {
+ if (only_structured) {
+ return -EINVAL;
}
- /* Tell the read handler to read another header. */
- s->reply.handle = 0;
+ *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,
+ NULL) < 0 ? -EIO : 0;
}
- s->requests[i].coroutine = NULL;
+ /* handle structured reply chunk */
+ assert(s->info.structured_reply);
+
+ if (s->reply.structured.type == NBD_SREP_TYPE_NONE) {
+ return 0;
+ }
+
+ if (s->reply.structured.type == NBD_SREP_TYPE_OFFSET_DATA) {
+ if (!qiov) {
+ return -EINVAL;
+ }
+
+ return nbd_co_receive_offset_data_payload(s, qiov);
+ }
+
+ if (nbd_srep_type_is_error(s->reply.structured.type)) {
+ payload = &local_payload;
+ }
+
+ ret = nbd_co_receive_structured_payload(s, payload);
+ if (ret < 0) {
+ return ret;
+ }
+
+ if (nbd_srep_type_is_error(s->reply.structured.type)) {
+ ret = nbd_parse_error_payload(&s->reply.structured, local_payload,
+ request_ret);
+ qemu_vfree(local_payload);
+ return ret;
+ }
+
+ return 0;
+}
+
+/* nbd_co_receive_one_chunk
+ * Read reply, wake up read_reply_co and set s->quit if needed.
+ * Return value is a fatal error code or normal nbd reply error code
+ */
+static int nbd_co_receive_one_chunk(NBDClientSession *s, uint64_t handle,
+ bool only_structured,
+ QEMUIOVector *qiov, NBDReply *reply,
+ void **payload)
+{
+ int request_ret;
+ int ret = nbd_co_do_receive_one_chunk(s, handle, only_structured,
+ &request_ret, qiov, payload);
+
+ if (ret < 0) {
+ s->quit = true;
+ } else {
+ /* For assert at loop start in nbd_read_reply_entry */
+ if (reply) {
+ *reply = s->reply;
+ }
+ s->reply.handle = 0;
+ ret = request_ret;
+ }
- /* Kick the read_reply_co to get the next reply. */
if (s->read_reply_co) {
aio_co_wake(s->read_reply_co);
}
+ return ret;
+}
+
+static int nbd_co_receive_return_code(NBDClientSession *s, uint64_t handle)
+{
+ int ret = 0;
+ int i = HANDLE_TO_INDEX(s, handle);
+ NBDReply reply;
+ bool only_structured = false;
+
+ do {
+ int rc = nbd_co_receive_one_chunk(s, handle, only_structured,
+ NULL, &reply, NULL);
+ if (rc < 0 || nbd_reply_is_simple(&reply)) {
+ if (ret == 0) {
+ ret = rc;
+ }
+ only_structured = true;
+ continue;
+ }
+
+ if (reply.structured.type != NBD_SREP_TYPE_NONE) {
+ /* not allowed reply type */
+ ret = -EIO;
+ s->quit = true;
+ break;
+ }
+
+ only_structured = true;
+ } while (!s->quit && nbd_reply_is_structured(&s->reply) &&
+ !(s->reply.structured.flags & NBD_SREP_FLAG_DONE));
+
+ s->requests[i].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 ret;
+}
+
+static int nbd_co_receive_cmdread_reply(NBDClientSession *s, uint64_t handle,
+ QEMUIOVector *qiov)
+{
+ int ret = 0;
+ int i = HANDLE_TO_INDEX(s, handle);
+ bool only_structured = s->info.structured_reply;
+ NBDReply reply;
+
+ do {
+ void *payload = NULL;
+ int rc = nbd_co_receive_one_chunk(s, handle, only_structured,
+ qiov, &reply, &payload);
+ if (rc < 0 || nbd_reply_is_simple(&reply)) {
+ if (ret == 0) {
+ ret = rc;
+ }
+ only_structured = true;
+ continue;
+ }
+
+ switch (reply.structured.type) {
+ case NBD_SREP_TYPE_OFFSET_DATA:
+ /* special cased in nbd_co_receive_one_chunk, data is already
+ * in qiov */
+ break;
+ case NBD_SREP_TYPE_OFFSET_HOLE:
+ ret = nbd_parse_offset_hole_payload(&reply.structured, payload,
+ qiov);
+ if (ret < 0) {
+ s->quit = true;
+ }
+ break;
+ default:
+ /* not allowed reply type */
+ ret = -EINVAL;
+ s->quit = true;
+ }
+
+ qemu_vfree(payload);
+ only_structured = true;
+ } while (!s->quit && nbd_reply_is_structured(&s->reply) &&
+ !(s->reply.structured.flags & NBD_SREP_FLAG_DONE));
+
+
+ s->requests[i].coroutine = NULL;
+
qemu_co_mutex_lock(&s->send_mutex);
s->in_flight--;
qemu_co_queue_next(&s->free_sema);
@@ -226,30 +522,31 @@ static int nbd_co_receive_reply(NBDClientSession *s,
static int nbd_co_request(BlockDriverState *bs,
NBDRequest *request,
- QEMUIOVector *qiov)
+ QEMUIOVector *write_qiov)
{
NBDClientSession *client = nbd_get_client_session(bs);
int ret;
- if (qiov) {
- assert(request->type == NBD_CMD_WRITE || request->type ==
NBD_CMD_READ);
- assert(request->len == iov_size(qiov->iov, qiov->niov));
+ assert(request->type != NBD_CMD_READ);
+ if (write_qiov) {
+ assert(request->type == NBD_CMD_WRITE);
+ assert(request->len == iov_size(write_qiov->iov, write_qiov->niov));
} else {
- assert(request->type != NBD_CMD_WRITE && request->type !=
NBD_CMD_READ);
+ assert(request->type != NBD_CMD_WRITE);
}
- ret = nbd_co_send_request(bs, request,
- request->type == NBD_CMD_WRITE ? qiov : NULL);
+ ret = nbd_co_send_request(bs, request, write_qiov);
if (ret < 0) {
return ret;
}
- return nbd_co_receive_reply(client, request->handle,
- request->type == NBD_CMD_READ ? qiov : NULL);
+ return nbd_co_receive_return_code(client, request->handle);
}
int nbd_client_co_preadv(BlockDriverState *bs, uint64_t offset,
uint64_t bytes, QEMUIOVector *qiov, int flags)
{
+ int ret;
+ NBDClientSession *client = nbd_get_client_session(bs);
NBDRequest request = {
.type = NBD_CMD_READ,
.from = offset,
@@ -259,7 +556,12 @@ int nbd_client_co_preadv(BlockDriverState *bs, uint64_t
offset,
assert(bytes <= NBD_MAX_BUFFER_SIZE);
assert(!flags);
- return nbd_co_request(bs, &request, qiov);
+ ret = nbd_co_send_request(bs, &request, NULL);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return nbd_co_receive_cmdread_reply(client, request.handle, qiov);
}
int nbd_client_co_pwritev(BlockDriverState *bs, uint64_t offset,
diff --git a/nbd/client.c b/nbd/client.c
index a38e1a7d8e..2f256ee771 100644
--- a/nbd/client.c
+++ b/nbd/client.c
@@ -687,6 +687,13 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char
*name,
if (fixedNewStyle) {
int result;
+ result = nbd_request_simple_option(ioc, NBD_OPT_STRUCTURED_REPLY,
+ errp);
+ if (result < 0) {
+ goto fail;
+ }
+ info->structured_reply = result == 1;
+
/* Try NBD_OPT_GO first - if it works, we are done (it
* also gives us a good message if the server requires
* TLS). If it is not available, fall back to
--
2.11.1
