nbd/server: Include human-readable message in structured errors

The NBD spec permits including a human-readable error string if
structured replies are in force, so we might as well send the
client the message that we logged on any error.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20171027104037.8319-9-eblake@redhat.com>
This commit is contained in:
Eric Blake 2017-10-27 12:40:33 +02:00
parent 5c54e7fa71
commit a57f6dea02
2 changed files with 14 additions and 8 deletions

View File

@ -1296,24 +1296,25 @@ static int coroutine_fn nbd_co_send_structured_read(NBDClient *client,
static int coroutine_fn nbd_co_send_structured_error(NBDClient *client,
uint64_t handle,
uint32_t error,
const char *msg,
Error **errp)
{
NBDStructuredError chunk;
int nbd_err = system_errno_to_nbd_errno(error);
struct iovec iov[] = {
{.iov_base = &chunk, .iov_len = sizeof(chunk)},
/* FIXME: Support human-readable error message */
{.iov_base = (char *)msg, .iov_len = msg ? strlen(msg) : 0},
};
assert(nbd_err);
trace_nbd_co_send_structured_error(handle, nbd_err,
nbd_err_lookup(nbd_err));
nbd_err_lookup(nbd_err), msg ? msg : "");
set_be_chunk(&chunk.h, NBD_REPLY_FLAG_DONE, NBD_REPLY_TYPE_ERROR, handle,
sizeof(chunk) - sizeof(chunk.h));
sizeof(chunk) - sizeof(chunk.h) + iov[1].iov_len);
stl_be_p(&chunk.error, nbd_err);
stw_be_p(&chunk.message_length, 0);
stw_be_p(&chunk.message_length, iov[1].iov_len);
return nbd_co_send_iov(client, iov, 1, errp);
return nbd_co_send_iov(client, iov, 1 + !!iov[1].iov_len, errp);
}
/* nbd_co_receive_request
@ -1414,6 +1415,7 @@ static coroutine_fn void nbd_trip(void *opaque)
int flags;
int reply_data_len = 0;
Error *local_err = NULL;
char *msg = NULL;
trace_nbd_trip();
if (client->closing) {
@ -1530,14 +1532,17 @@ reply:
if (local_err) {
/* If we get here, local_err was not a fatal error, and should be sent
* to the client. */
assert(ret < 0);
msg = g_strdup(error_get_pretty(local_err));
error_report_err(local_err);
local_err = NULL;
}
if (client->structured_reply && request.type == NBD_CMD_READ) {
if (client->structured_reply &&
(ret < 0 || request.type == NBD_CMD_READ)) {
if (ret < 0) {
ret = nbd_co_send_structured_error(req->client, request.handle,
-ret, &local_err);
-ret, msg, &local_err);
} else {
ret = nbd_co_send_structured_read(req->client, request.handle,
request.from, req->data,
@ -1548,6 +1553,7 @@ reply:
ret < 0 ? -ret : 0,
req->data, reply_data_len, &local_err);
}
g_free(msg);
if (ret < 0) {
error_prepend(&local_err, "Failed to send reply: ");
goto disconnect;

View File

@ -57,7 +57,7 @@ nbd_blk_aio_attached(const char *name, void *ctx) "Export %s: Attaching clients
nbd_blk_aio_detach(const char *name, void *ctx) "Export %s: Detaching clients from AIO context %p\n"
nbd_co_send_simple_reply(uint64_t handle, uint32_t error, const char *errname, int len) "Send simple reply: handle = %" PRIu64 ", error = %" PRIu32 " (%s), len = %d"
nbd_co_send_structured_read(uint64_t handle, uint64_t offset, void *data, size_t size) "Send structured read data reply: handle = %" PRIu64 ", offset = %" PRIu64 ", data = %p, len = %zu"
nbd_co_send_structured_error(uint64_t handle, int err, const char *errname) "Send structured error reply: handle = %" PRIu64 ", error = %d (%s)"
nbd_co_send_structured_error(uint64_t handle, int err, const char *errname, const char *msg) "Send structured error reply: handle = %" PRIu64 ", error = %d (%s), msg = '%s'"
nbd_co_receive_request_decode_type(uint64_t handle, uint16_t type, const char *name) "Decoding type: handle = %" PRIu64 ", type = %" PRIu16 " (%s)"
nbd_co_receive_request_payload_received(uint64_t handle, uint32_t len) "Payload received: handle = %" PRIu64 ", len = %" PRIu32
nbd_co_receive_request_cmd_write(uint32_t len) "Reading %" PRIu32 " byte(s)"