From fa35591b9cb9a7fd0af2d8c2d8848abba30d3c69 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Mon, 27 Jul 2020 21:47:47 +0300 Subject: [PATCH] block/nbd: split nbd_establish_connection out of nbd_client_connect We are going to implement non-blocking version of nbd_establish_connection, which for a while will be used only for nbd_reconnect_attempt, not for nbd_open, so we need to call it separately. Refactor nbd_reconnect_attempt in a way which makes next commit simpler. Signed-off-by: Vladimir Sementsov-Ogievskiy Message-Id: <20200727184751.15704-2-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake Signed-off-by: Eric Blake --- block/nbd.c | 60 +++++++++++++++++++++++++++------------------- block/trace-events | 4 ++-- 2 files changed, 38 insertions(+), 26 deletions(-) diff --git a/block/nbd.c b/block/nbd.c index 8934bcb479..3558c173e3 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -93,7 +93,10 @@ typedef struct BDRVNBDState { char *x_dirty_bitmap; } BDRVNBDState; -static int nbd_client_connect(BlockDriverState *bs, Error **errp); +static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr, + Error **errp); +static int nbd_client_handshake(BlockDriverState *bs, QIOChannelSocket *sioc, + Error **errp); static void nbd_clear_bdrvstate(BDRVNBDState *s) { @@ -241,7 +244,9 @@ static bool nbd_client_connecting_wait(BDRVNBDState *s) static coroutine_fn void nbd_reconnect_attempt(BDRVNBDState *s) { + int ret; Error *local_err = NULL; + QIOChannelSocket *sioc; if (!nbd_client_connecting(s)) { return; @@ -280,19 +285,25 @@ static coroutine_fn void nbd_reconnect_attempt(BDRVNBDState *s) s->ioc = NULL; } - s->connect_status = nbd_client_connect(s->bs, &local_err); + sioc = nbd_establish_connection(s->saddr, &local_err); + if (!sioc) { + ret = -ECONNREFUSED; + goto out; + } + + ret = nbd_client_handshake(s->bs, sioc, &local_err); + +out: + s->connect_status = ret; error_free(s->connect_err); s->connect_err = NULL; error_propagate(&s->connect_err, local_err); - if (s->connect_status < 0) { - /* failed attempt */ - return; + if (ret >= 0) { + /* successfully connected */ + s->state = NBD_CLIENT_CONNECTED; + qemu_co_queue_restart_all(&s->free_sema); } - - /* successfully connected */ - s->state = NBD_CLIENT_CONNECTED; - qemu_co_queue_restart_all(&s->free_sema); } static coroutine_fn void nbd_co_reconnect_loop(BDRVNBDState *s) @@ -1425,24 +1436,15 @@ static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr, return sioc; } -static int nbd_client_connect(BlockDriverState *bs, Error **errp) +/* nbd_client_handshake takes ownership on sioc. On failure it is unref'ed. */ +static int nbd_client_handshake(BlockDriverState *bs, QIOChannelSocket *sioc, + Error **errp) { BDRVNBDState *s = (BDRVNBDState *)bs->opaque; AioContext *aio_context = bdrv_get_aio_context(bs); int ret; - /* - * establish TCP connection, return error if it fails - * TODO: Configurable retry-until-timeout behaviour. - */ - QIOChannelSocket *sioc = nbd_establish_connection(s->saddr, errp); - - if (!sioc) { - return -ECONNREFUSED; - } - - /* NBD handshake */ - trace_nbd_client_connect(s->export); + trace_nbd_client_handshake(s->export); qio_channel_set_blocking(QIO_CHANNEL(sioc), false, NULL); qio_channel_attach_aio_context(QIO_CHANNEL(sioc), aio_context); @@ -1489,7 +1491,7 @@ static int nbd_client_connect(BlockDriverState *bs, Error **errp) object_ref(OBJECT(s->ioc)); } - trace_nbd_client_connect_success(s->export); + trace_nbd_client_handshake_success(s->export); return 0; @@ -1894,6 +1896,7 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags, { int ret; BDRVNBDState *s = (BDRVNBDState *)bs->opaque; + QIOChannelSocket *sioc; ret = nbd_process_options(bs, options, errp); if (ret < 0) { @@ -1904,7 +1907,16 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags, qemu_co_mutex_init(&s->send_mutex); qemu_co_queue_init(&s->free_sema); - ret = nbd_client_connect(bs, errp); + /* + * establish TCP connection, return error if it fails + * TODO: Configurable retry-until-timeout behaviour. + */ + sioc = nbd_establish_connection(s->saddr, errp); + if (!sioc) { + return -ECONNREFUSED; + } + + ret = nbd_client_handshake(bs, sioc, errp); if (ret < 0) { nbd_clear_bdrvstate(s); return ret; diff --git a/block/trace-events b/block/trace-events index d3533ca896..9158335061 100644 --- a/block/trace-events +++ b/block/trace-events @@ -168,8 +168,8 @@ nbd_parse_blockstatus_compliance(const char *err) "ignoring extra data from non- nbd_structured_read_compliance(const char *type) "server sent non-compliant unaligned read %s chunk" nbd_read_reply_entry_fail(int ret, const char *err) "ret = %d, err: %s" nbd_co_request_fail(uint64_t from, uint32_t len, uint64_t handle, uint16_t flags, uint16_t type, const char *name, int ret, const char *err) "Request failed { .from = %" PRIu64", .len = %" PRIu32 ", .handle = %" PRIu64 ", .flags = 0x%" PRIx16 ", .type = %" PRIu16 " (%s) } ret = %d, err: %s" -nbd_client_connect(const char *export_name) "export '%s'" -nbd_client_connect_success(const char *export_name) "export '%s'" +nbd_client_handshake(const char *export_name) "export '%s'" +nbd_client_handshake_success(const char *export_name) "export '%s'" # ssh.c ssh_restart_coroutine(void *co) "co=%p"