diff options
| -rw-r--r-- | block/nbd.c | 331 |
1 files changed, 268 insertions, 63 deletions
diff --git a/block/nbd.c b/block/nbd.c index fd78e5f330..123976171c 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -1,6 +1,7 @@ /* * QEMU Block driver for NBD * + * Copyright (c) 2019 Virtuozzo International GmbH. * Copyright (C) 2016 Red Hat, Inc. * Copyright (C) 2008 Bull S.A.S. * Author: Laurent Vivier <Laurent.Vivier@bull.net> @@ -55,6 +56,8 @@ typedef struct { } NBDClientRequest; typedef enum NBDClientState { + NBD_CLIENT_CONNECTING_WAIT, + NBD_CLIENT_CONNECTING_NOWAIT, NBD_CLIENT_CONNECTED, NBD_CLIENT_QUIT } NBDClientState; @@ -67,8 +70,14 @@ typedef struct BDRVNBDState { CoMutex send_mutex; CoQueue free_sema; Coroutine *connection_co; + QemuCoSleepState *connection_co_sleep_ns_state; + bool drained; + bool wait_drained_end; int in_flight; NBDClientState state; + int connect_status; + Error *connect_err; + bool wait_in_flight; NBDClientRequest requests[MAX_NBD_REQUESTS]; NBDReply reply; @@ -83,10 +92,21 @@ typedef struct BDRVNBDState { char *x_dirty_bitmap; } BDRVNBDState; -/* @ret will be used for reconnect in future */ +static int nbd_client_connect(BlockDriverState *bs, Error **errp); + static void nbd_channel_error(BDRVNBDState *s, int ret) { - s->state = NBD_CLIENT_QUIT; + if (ret == -EIO) { + if (s->state == NBD_CLIENT_CONNECTED) { + s->state = s->reconnect_delay ? NBD_CLIENT_CONNECTING_WAIT : + NBD_CLIENT_CONNECTING_NOWAIT; + } + } else { + if (s->state == NBD_CLIENT_CONNECTED) { + qio_channel_shutdown(s->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL); + } + s->state = NBD_CLIENT_QUIT; + } } static void nbd_recv_coroutines_wake_all(BDRVNBDState *s) @@ -129,7 +149,13 @@ static void nbd_client_attach_aio_context(BlockDriverState *bs, { BDRVNBDState *s = (BDRVNBDState *)bs->opaque; - qio_channel_attach_aio_context(QIO_CHANNEL(s->ioc), new_context); + /* + * s->connection_co is either yielded from nbd_receive_reply or from + * nbd_co_reconnect_loop() + */ + if (s->state == NBD_CLIENT_CONNECTED) { + qio_channel_attach_aio_context(QIO_CHANNEL(s->ioc), new_context); + } bdrv_inc_in_flight(bs); @@ -140,24 +166,150 @@ static void nbd_client_attach_aio_context(BlockDriverState *bs, aio_wait_bh_oneshot(new_context, nbd_client_attach_aio_context_bh, bs); } +static void coroutine_fn nbd_client_co_drain_begin(BlockDriverState *bs) +{ + BDRVNBDState *s = (BDRVNBDState *)bs->opaque; -static void nbd_teardown_connection(BlockDriverState *bs) + s->drained = true; + if (s->connection_co_sleep_ns_state) { + qemu_co_sleep_wake(s->connection_co_sleep_ns_state); + } +} + +static void coroutine_fn nbd_client_co_drain_end(BlockDriverState *bs) { BDRVNBDState *s = (BDRVNBDState *)bs->opaque; - assert(s->ioc); + s->drained = false; + if (s->wait_drained_end) { + s->wait_drained_end = false; + aio_co_wake(s->connection_co); + } +} + - /* finish any pending coroutines */ - qio_channel_shutdown(s->ioc, - QIO_CHANNEL_SHUTDOWN_BOTH, - NULL); +static void nbd_teardown_connection(BlockDriverState *bs) +{ + BDRVNBDState *s = (BDRVNBDState *)bs->opaque; + + if (s->state == NBD_CLIENT_CONNECTED) { + /* finish any pending coroutines */ + assert(s->ioc); + qio_channel_shutdown(s->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL); + } + s->state = NBD_CLIENT_QUIT; + if (s->connection_co) { + if (s->connection_co_sleep_ns_state) { + qemu_co_sleep_wake(s->connection_co_sleep_ns_state); + } + } BDRV_POLL_WHILE(bs, s->connection_co); +} - nbd_client_detach_aio_context(bs); - object_unref(OBJECT(s->sioc)); - s->sioc = NULL; - object_unref(OBJECT(s->ioc)); - s->ioc = NULL; +static bool nbd_client_connecting(BDRVNBDState *s) +{ + return s->state == NBD_CLIENT_CONNECTING_WAIT || + s->state == NBD_CLIENT_CONNECTING_NOWAIT; +} + +static bool nbd_client_connecting_wait(BDRVNBDState *s) +{ + return s->state == NBD_CLIENT_CONNECTING_WAIT; +} + +static coroutine_fn void nbd_reconnect_attempt(BDRVNBDState *s) +{ + Error *local_err = NULL; + + if (!nbd_client_connecting(s)) { + return; + } + + /* Wait for completion of all in-flight requests */ + + qemu_co_mutex_lock(&s->send_mutex); + + while (s->in_flight > 0) { + qemu_co_mutex_unlock(&s->send_mutex); + nbd_recv_coroutines_wake_all(s); + s->wait_in_flight = true; + qemu_coroutine_yield(); + s->wait_in_flight = false; + qemu_co_mutex_lock(&s->send_mutex); + } + + qemu_co_mutex_unlock(&s->send_mutex); + + if (!nbd_client_connecting(s)) { + return; + } + + /* + * Now we are sure that nobody is accessing the channel, and no one will + * try until we set the state to CONNECTED. + */ + + /* Finalize previous connection if any */ + if (s->ioc) { + nbd_client_detach_aio_context(s->bs); + object_unref(OBJECT(s->sioc)); + s->sioc = NULL; + object_unref(OBJECT(s->ioc)); + s->ioc = NULL; + } + + s->connect_status = nbd_client_connect(s->bs, &local_err); + error_free(s->connect_err); + s->connect_err = NULL; + error_propagate(&s->connect_err, local_err); + + if (s->connect_status < 0) { + /* failed attempt */ + return; + } + + /* 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) +{ + uint64_t start_time_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); + uint64_t delay_ns = s->reconnect_delay * NANOSECONDS_PER_SECOND; + uint64_t timeout = 1 * NANOSECONDS_PER_SECOND; + uint64_t max_timeout = 16 * NANOSECONDS_PER_SECOND; + + nbd_reconnect_attempt(s); + + while (nbd_client_connecting(s)) { + if (s->state == NBD_CLIENT_CONNECTING_WAIT && + qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - start_time_ns > delay_ns) + { + s->state = NBD_CLIENT_CONNECTING_NOWAIT; + qemu_co_queue_restart_all(&s->free_sema); + } + + qemu_co_sleep_ns_wakeable(QEMU_CLOCK_REALTIME, timeout, + &s->connection_co_sleep_ns_state); + if (s->drained) { + bdrv_dec_in_flight(s->bs); + s->wait_drained_end = true; + while (s->drained) { + /* + * We may be entered once from nbd_client_attach_aio_context_bh + * and then from nbd_client_co_drain_end. So here is a loop. + */ + qemu_coroutine_yield(); + } + bdrv_inc_in_flight(s->bs); + } + if (timeout < max_timeout) { + timeout *= 2; + } + + nbd_reconnect_attempt(s); + } } static coroutine_fn void nbd_connection_entry(void *opaque) @@ -177,16 +329,26 @@ static coroutine_fn void nbd_connection_entry(void *opaque) * Therefore we keep an additional in_flight reference all the time and * only drop it temporarily here. */ + + if (nbd_client_connecting(s)) { + nbd_co_reconnect_loop(s); + } + + if (s->state != NBD_CLIENT_CONNECTED) { + continue; + } + assert(s->reply.handle == 0); ret = nbd_receive_reply(s->bs, s->ioc, &s->reply, &local_err); if (local_err) { trace_nbd_read_reply_entry_fail(ret, error_get_pretty(local_err)); error_free(local_err); + local_err = NULL; } if (ret <= 0) { nbd_channel_error(s, ret ? ret : -EIO); - break; + continue; } /* @@ -201,7 +363,7 @@ static coroutine_fn void nbd_connection_entry(void *opaque) (nbd_reply_is_structured(&s->reply) && !s->info.structured_reply)) { nbd_channel_error(s, -EINVAL); - break; + continue; } /* @@ -220,10 +382,19 @@ static coroutine_fn void nbd_connection_entry(void *opaque) qemu_coroutine_yield(); } + qemu_co_queue_restart_all(&s->free_sema); nbd_recv_coroutines_wake_all(s); bdrv_dec_in_flight(s->bs); s->connection_co = NULL; + if (s->ioc) { + nbd_client_detach_aio_context(s->bs); + object_unref(OBJECT(s->sioc)); + s->sioc = NULL; + object_unref(OBJECT(s->ioc)); + s->ioc = NULL; + } + aio_wait_kick(); } @@ -235,7 +406,7 @@ static int nbd_co_send_request(BlockDriverState *bs, int rc, i = -1; qemu_co_mutex_lock(&s->send_mutex); - while (s->in_flight == MAX_NBD_REQUESTS) { + while (s->in_flight == MAX_NBD_REQUESTS || nbd_client_connecting_wait(s)) { qemu_co_queue_wait(&s->free_sema, &s->send_mutex); } @@ -286,7 +457,11 @@ err: s->requests[i].coroutine = NULL; s->in_flight--; } - qemu_co_queue_next(&s->free_sema); + if (s->in_flight == 0 && s->wait_in_flight) { + aio_co_wake(s->connection_co); + } else { + qemu_co_queue_next(&s->free_sema); + } } qemu_co_mutex_unlock(&s->send_mutex); return rc; @@ -666,10 +841,15 @@ static coroutine_fn int nbd_co_receive_one_chunk( } else { /* For assert at loop start in nbd_connection_entry */ *reply = s->reply; - s->reply.handle = 0; } + s->reply.handle = 0; - if (s->connection_co) { + if (s->connection_co && !s->wait_in_flight) { + /* + * We must check s->wait_in_flight, because we may entered by + * nbd_recv_coroutines_wake_all(), in this case we should not + * wake connection_co here, it will woken by last request. + */ aio_co_wake(s->connection_co); } @@ -781,7 +961,11 @@ break_loop: qemu_co_mutex_lock(&s->send_mutex); s->in_flight--; - qemu_co_queue_next(&s->free_sema); + if (s->in_flight == 0 && s->wait_in_flight) { + aio_co_wake(s->connection_co); + } else { + qemu_co_queue_next(&s->free_sema); + } qemu_co_mutex_unlock(&s->send_mutex); return false; @@ -927,20 +1111,26 @@ static int nbd_co_request(BlockDriverState *bs, NBDRequest *request, } else { assert(request->type != NBD_CMD_WRITE); } - ret = nbd_co_send_request(bs, request, write_qiov); - if (ret < 0) { - return ret; - } - ret = nbd_co_receive_return_code(s, request->handle, - &request_ret, &local_err); - if (local_err) { - trace_nbd_co_request_fail(request->from, request->len, request->handle, - request->flags, request->type, - nbd_cmd_lookup(request->type), - ret, error_get_pretty(local_err)); - error_free(local_err); - } + do { + ret = nbd_co_send_request(bs, request, write_qiov); + if (ret < 0) { + continue; + } + + ret = nbd_co_receive_return_code(s, request->handle, + &request_ret, &local_err); + if (local_err) { + trace_nbd_co_request_fail(request->from, request->len, + request->handle, request->flags, + request->type, + nbd_cmd_lookup(request->type), + ret, error_get_pretty(local_err)); + error_free(local_err); + local_err = NULL; + } + } while (ret < 0 && nbd_client_connecting_wait(s)); + return ret ? ret : request_ret; } @@ -981,20 +1171,24 @@ static int nbd_client_co_preadv(BlockDriverState *bs, uint64_t offset, request.len -= slop; } - ret = nbd_co_send_request(bs, &request, NULL); - if (ret < 0) { - return ret; - } + do { + ret = nbd_co_send_request(bs, &request, NULL); + if (ret < 0) { + continue; + } + + ret = nbd_co_receive_cmdread_reply(s, request.handle, offset, qiov, + &request_ret, &local_err); + if (local_err) { + trace_nbd_co_request_fail(request.from, request.len, request.handle, + request.flags, request.type, + nbd_cmd_lookup(request.type), + ret, error_get_pretty(local_err)); + error_free(local_err); + local_err = NULL; + } + } while (ret < 0 && nbd_client_connecting_wait(s)); - ret = nbd_co_receive_cmdread_reply(s, request.handle, offset, qiov, - &request_ret, &local_err); - if (local_err) { - trace_nbd_co_request_fail(request.from, request.len, request.handle, - request.flags, request.type, - nbd_cmd_lookup(request.type), - ret, error_get_pretty(local_err)); - error_free(local_err); - } return ret ? ret : request_ret; } @@ -1131,20 +1325,25 @@ static int coroutine_fn nbd_client_co_block_status( if (s->info.min_block) { assert(QEMU_IS_ALIGNED(request.len, s->info.min_block)); } - ret = nbd_co_send_request(bs, &request, NULL); - if (ret < 0) { - return ret; - } + do { + ret = nbd_co_send_request(bs, &request, NULL); + if (ret < 0) { + continue; + } + + ret = nbd_co_receive_blockstatus_reply(s, request.handle, bytes, + &extent, &request_ret, + &local_err); + if (local_err) { + trace_nbd_co_request_fail(request.from, request.len, request.handle, + request.flags, request.type, + nbd_cmd_lookup(request.type), + ret, error_get_pretty(local_err)); + error_free(local_err); + local_err = NULL; + } + } while (ret < 0 && nbd_client_connecting_wait(s)); - ret = nbd_co_receive_blockstatus_reply(s, request.handle, bytes, - &extent, &request_ret, &local_err); - if (local_err) { - trace_nbd_co_request_fail(request.from, request.len, request.handle, - request.flags, request.type, - nbd_cmd_lookup(request.type), - ret, error_get_pretty(local_err)); - error_free(local_err); - } if (ret < 0 || request_ret < 0) { return ret ? ret : request_ret; } @@ -1175,9 +1374,9 @@ static void nbd_client_close(BlockDriverState *bs) BDRVNBDState *s = (BDRVNBDState *)bs->opaque; NBDRequest request = { .type = NBD_CMD_DISC }; - assert(s->ioc); - - nbd_send_request(s->ioc, &request); + if (s->ioc) { + nbd_send_request(s->ioc, &request); + } nbd_teardown_connection(bs); } @@ -1821,6 +2020,8 @@ static BlockDriver bdrv_nbd = { .bdrv_getlength = nbd_getlength, .bdrv_detach_aio_context = nbd_client_detach_aio_context, .bdrv_attach_aio_context = nbd_client_attach_aio_context, + .bdrv_co_drain_begin = nbd_client_co_drain_begin, + .bdrv_co_drain_end = nbd_client_co_drain_end, .bdrv_refresh_filename = nbd_refresh_filename, .bdrv_co_block_status = nbd_client_co_block_status, .bdrv_dirname = nbd_dirname, @@ -1844,6 +2045,8 @@ static BlockDriver bdrv_nbd_tcp = { .bdrv_getlength = nbd_getlength, .bdrv_detach_aio_context = nbd_client_detach_aio_context, .bdrv_attach_aio_context = nbd_client_attach_aio_context, + .bdrv_co_drain_begin = nbd_client_co_drain_begin, + .bdrv_co_drain_end = nbd_client_co_drain_end, .bdrv_refresh_filename = nbd_refresh_filename, .bdrv_co_block_status = nbd_client_co_block_status, .bdrv_dirname = nbd_dirname, @@ -1867,6 +2070,8 @@ static BlockDriver bdrv_nbd_unix = { .bdrv_getlength = nbd_getlength, .bdrv_detach_aio_context = nbd_client_detach_aio_context, .bdrv_attach_aio_context = nbd_client_attach_aio_context, + .bdrv_co_drain_begin = nbd_client_co_drain_begin, + .bdrv_co_drain_end = nbd_client_co_drain_end, .bdrv_refresh_filename = nbd_refresh_filename, .bdrv_co_block_status = nbd_client_co_block_status, .bdrv_dirname = nbd_dirname, |