case EFBIG:
case ENOSPC:
return NBD_ENOSPC;
+ case ESHUTDOWN:
+ return NBD_ESHUTDOWN;
case EINVAL:
default:
return NBD_EINVAL;
int refcount;
void (*close)(NBDClient *client);
+ bool no_zeroes;
NBDExport *exp;
QCryptoTLSCreds *tlscreds;
char *tlsaclname;
CoMutex send_lock;
Coroutine *send_coroutine;
- bool can_read;
-
QTAILQ_ENTRY(NBDClient) next;
int nb_requests;
bool closing;
/* That's all folks */
-static void nbd_set_handlers(NBDClient *client);
-static void nbd_unset_handlers(NBDClient *client);
-static void nbd_update_can_read(NBDClient *client);
+static void nbd_client_receive_next_request(NBDClient *client);
static gboolean nbd_negotiate_continue(QIOChannel *ioc,
GIOCondition condition,
fixedNewstyle = true;
flags &= ~NBD_FLAG_C_FIXED_NEWSTYLE;
}
+ if (flags & NBD_FLAG_C_NO_ZEROES) {
+ TRACE("Client supports no zeroes at handshake end");
+ client->no_zeroes = true;
+ flags &= ~NBD_FLAG_C_NO_ZEROES;
+ }
if (flags != 0) {
TRACE("Unknown client flags 0x%" PRIx32 " received", flags);
return -EIO;
if (ret < 0) {
return ret;
}
+ /* Let the client keep trying, unless they asked to quit */
+ if (clientflags == NBD_OPT_ABORT) {
+ return -EINVAL;
+ }
break;
}
} else if (fixedNewstyle) {
break;
case NBD_OPT_ABORT:
+ /* NBD spec says we must try to reply before
+ * disconnecting, but that we must also tolerate
+ * guests that don't wait for our reply. */
+ nbd_negotiate_send_rep(client->ioc, NBD_REP_ACK, clientflags);
return -EINVAL;
case NBD_OPT_EXPORT_NAME:
char buf[8 + 8 + 8 + 128];
int rc;
const uint16_t myflags = (NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_TRIM |
- NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA);
+ NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA |
+ NBD_FLAG_SEND_WRITE_ZEROES);
bool oldStyle;
+ size_t len;
/* Old style negotiation header without options
[ 0 .. 7] passwd ("NBDMAGIC")
....options sent....
[18 .. 25] size
[26 .. 27] export flags
- [28 .. 151] reserved (0)
+ [28 .. 151] reserved (0, omit if no_zeroes)
*/
qio_channel_set_blocking(client->ioc, false, NULL);
stw_be_p(buf + 26, client->exp->nbdflags | myflags);
} else {
stq_be_p(buf + 8, NBD_OPTS_MAGIC);
- stw_be_p(buf + 16, NBD_FLAG_FIXED_NEWSTYLE);
+ stw_be_p(buf + 16, NBD_FLAG_FIXED_NEWSTYLE | NBD_FLAG_NO_ZEROES);
}
if (oldStyle) {
client->exp->size, client->exp->nbdflags | myflags);
stq_be_p(buf + 18, client->exp->size);
stw_be_p(buf + 26, client->exp->nbdflags | myflags);
- if (nbd_negotiate_write(client->ioc, buf + 18, sizeof(buf) - 18) !=
- sizeof(buf) - 18) {
+ len = client->no_zeroes ? 10 : sizeof(buf) - 18;
+ if (nbd_negotiate_write(client->ioc, buf + 18, len) != len) {
LOG("write failed");
goto fail;
}
*/
assert(client->closing);
- nbd_unset_handlers(client);
+ qio_channel_detach_aio_context(client->ioc);
object_unref(OBJECT(client->sioc));
object_unref(OBJECT(client->ioc));
if (client->tlscreds) {
assert(client->nb_requests <= MAX_NBD_REQUESTS - 1);
client->nb_requests++;
- nbd_update_can_read(client);
req = g_new0(NBDRequestData, 1);
nbd_client_get(client);
g_free(req);
client->nb_requests--;
- nbd_update_can_read(client);
+ nbd_client_receive_next_request(client);
+
nbd_client_put(client);
}
exp->ctx = ctx;
QTAILQ_FOREACH(client, &exp->clients, next) {
- nbd_set_handlers(client);
+ qio_channel_attach_aio_context(client->ioc, ctx);
+ if (client->recv_coroutine) {
+ aio_co_schedule(ctx, client->recv_coroutine);
+ }
+ if (client->send_coroutine) {
+ aio_co_schedule(ctx, client->send_coroutine);
+ }
}
}
TRACE("Export %s: Detaching clients from AIO context %p\n", exp->name, exp->ctx);
QTAILQ_FOREACH(client, &exp->clients, next) {
- nbd_unset_handlers(client);
+ qio_channel_detach_aio_context(client->ioc);
}
exp->ctx = NULL;
g_assert(qemu_in_coroutine());
qemu_co_mutex_lock(&client->send_lock);
client->send_coroutine = qemu_coroutine_self();
- nbd_set_handlers(client);
if (!len) {
rc = nbd_send_reply(client->ioc, reply);
}
client->send_coroutine = NULL;
- nbd_set_handlers(client);
qemu_co_mutex_unlock(&client->send_lock);
return rc;
}
ssize_t rc;
g_assert(qemu_in_coroutine());
- client->recv_coroutine = qemu_coroutine_self();
- nbd_update_can_read(client);
-
+ assert(client->recv_coroutine == qemu_coroutine_self());
rc = nbd_receive_request(client->ioc, request);
if (rc < 0) {
if (rc != -EAGAIN) {
rc = request->type == NBD_CMD_WRITE ? -ENOSPC : -EINVAL;
goto out;
}
- if (request->flags & ~NBD_CMD_FLAG_FUA) {
+ if (request->flags & ~(NBD_CMD_FLAG_FUA | NBD_CMD_FLAG_NO_HOLE)) {
LOG("unsupported flags (got 0x%x)", request->flags);
rc = -EINVAL;
goto out;
}
+ if (request->type != NBD_CMD_WRITE_ZEROES &&
+ (request->flags & NBD_CMD_FLAG_NO_HOLE)) {
+ LOG("unexpected flags (got 0x%x)", request->flags);
+ rc = -EINVAL;
+ goto out;
+ }
rc = 0;
out:
client->recv_coroutine = NULL;
- nbd_update_can_read(client);
+ nbd_client_receive_next_request(client);
return rc;
}
-static void nbd_trip(void *opaque)
+/* Owns a reference to the NBDClient passed as opaque. */
+static coroutine_fn void nbd_trip(void *opaque)
{
NBDClient *client = opaque;
NBDExport *exp = client->exp;
NBDRequestData *req;
- NBDRequest request;
+ NBDRequest request = { 0 }; /* GCC thinks it can be used uninitialized */
NBDReply reply;
ssize_t ret;
int flags;
TRACE("Reading request.");
if (client->closing) {
+ nbd_client_put(client);
return;
}
}
break;
+ case NBD_CMD_WRITE_ZEROES:
+ TRACE("Request type is WRITE_ZEROES");
+
+ if (exp->nbdflags & NBD_FLAG_READ_ONLY) {
+ TRACE("Server is read-only, return error");
+ reply.error = EROFS;
+ goto error_reply;
+ }
+
+ TRACE("Writing to device");
+
+ flags = 0;
+ if (request.flags & NBD_CMD_FLAG_FUA) {
+ flags |= BDRV_REQ_FUA;
+ }
+ if (!(request.flags & NBD_CMD_FLAG_NO_HOLE)) {
+ flags |= BDRV_REQ_MAY_UNMAP;
+ }
+ ret = blk_pwrite_zeroes(exp->blk, request.from + exp->dev_offset,
+ request.len, flags);
+ if (ret < 0) {
+ LOG("writing to file failed");
+ reply.error = -ret;
+ goto error_reply;
+ }
+
+ if (nbd_co_send_reply(req, &reply, 0) < 0) {
+ goto out;
+ }
+ break;
+
case NBD_CMD_DISC:
/* unreachable, thanks to special case in nbd_co_receive_request() */
abort();
done:
nbd_request_put(req);
+ nbd_client_put(client);
return;
out:
nbd_request_put(req);
client_close(client);
+ nbd_client_put(client);
}
-static void nbd_read(void *opaque)
-{
- NBDClient *client = opaque;
-
- if (client->recv_coroutine) {
- qemu_coroutine_enter(client->recv_coroutine);
- } else {
- qemu_coroutine_enter(qemu_coroutine_create(nbd_trip, client));
- }
-}
-
-static void nbd_restart_write(void *opaque)
-{
- NBDClient *client = opaque;
-
- qemu_coroutine_enter(client->send_coroutine);
-}
-
-static void nbd_set_handlers(NBDClient *client)
-{
- if (client->exp && client->exp->ctx) {
- aio_set_fd_handler(client->exp->ctx, client->sioc->fd,
- true,
- client->can_read ? nbd_read : NULL,
- client->send_coroutine ? nbd_restart_write : NULL,
- client);
- }
-}
-
-static void nbd_unset_handlers(NBDClient *client)
-{
- if (client->exp && client->exp->ctx) {
- aio_set_fd_handler(client->exp->ctx, client->sioc->fd,
- true, NULL, NULL, NULL);
- }
-}
-
-static void nbd_update_can_read(NBDClient *client)
+static void nbd_client_receive_next_request(NBDClient *client)
{
- bool can_read = client->recv_coroutine ||
- client->nb_requests < MAX_NBD_REQUESTS;
-
- if (can_read != client->can_read) {
- client->can_read = can_read;
- nbd_set_handlers(client);
-
- /* There is no need to invoke aio_notify(), since aio_set_fd_handler()
- * in nbd_set_handlers() will have taken care of that */
+ if (!client->recv_coroutine && client->nb_requests < MAX_NBD_REQUESTS) {
+ nbd_client_get(client);
+ client->recv_coroutine = qemu_coroutine_create(nbd_trip, client);
+ aio_co_schedule(client->exp->ctx, client->recv_coroutine);
}
}
goto out;
}
qemu_co_mutex_init(&client->send_lock);
- nbd_set_handlers(client);
if (exp) {
QTAILQ_INSERT_TAIL(&exp->clients, client, next);
}
+
+ nbd_client_receive_next_request(client);
+
out:
g_free(data);
}
object_ref(OBJECT(client->sioc));
client->ioc = QIO_CHANNEL(sioc);
object_ref(OBJECT(client->ioc));
- client->can_read = true;
client->close = close_fn;
data->client = client;
projects / mirror_qemu.git / blobdiff