From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
To: qemu-block@nongnu.org
Cc: qemu-devel@nongnu.org, vsementsov@virtuozzo.com,
eblake@redhat.com, mreitz@redhat.com, kwolf@redhat.com,
pbonzini@redhat.com
Subject: [PATCH v4 17/32] nbd: move connection code from block/nbd to nbd/client-connection
Date: Thu, 10 Jun 2021 13:07:47 +0300 [thread overview]
Message-ID: <20210610100802.5888-18-vsementsov@virtuozzo.com> (raw)
In-Reply-To: <20210610100802.5888-1-vsementsov@virtuozzo.com>
We now have bs-independent connection API, which consists of four
functions:
nbd_client_connection_new()
nbd_client_connection_release()
nbd_co_establish_connection()
nbd_co_establish_connection_cancel()
Move them to a separate file together with NBDClientConnection
structure which becomes private to the new API.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
include/block/nbd.h | 11 ++
block/nbd.c | 206 -----------------------------------
nbd/client-connection.c | 231 ++++++++++++++++++++++++++++++++++++++++
nbd/meson.build | 1 +
4 files changed, 243 insertions(+), 206 deletions(-)
create mode 100644 nbd/client-connection.c
diff --git a/include/block/nbd.h b/include/block/nbd.h
index 5f34d23bb0..57381be76f 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -406,4 +406,15 @@ const char *nbd_info_lookup(uint16_t info);
const char *nbd_cmd_lookup(uint16_t info);
const char *nbd_err_lookup(int err);
+/* nbd/client-connection.c */
+typedef struct NBDClientConnection NBDClientConnection;
+
+NBDClientConnection *nbd_client_connection_new(const SocketAddress *saddr);
+void nbd_client_connection_release(NBDClientConnection *conn);
+
+QIOChannelSocket *coroutine_fn
+nbd_co_establish_connection(NBDClientConnection *conn, Error **errp);
+
+void coroutine_fn nbd_co_establish_connection_cancel(NBDClientConnection *conn);
+
#endif
diff --git a/block/nbd.c b/block/nbd.c
index b34957e464..26914509f1 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -66,32 +66,6 @@ typedef enum NBDClientState {
NBD_CLIENT_QUIT
} NBDClientState;
-typedef struct NBDClientConnection {
- /* Initialization constants */
- SocketAddress *saddr; /* address to connect to */
-
- QemuMutex mutex;
-
- /*
- * @sioc and @err present a result of connection attempt.
- * While running is true, they are used only by thread, mutex locking is not
- * needed. When thread is finished nbd_co_establish_connection steal these
- * pointers under mutex.
- */
- QIOChannelSocket *sioc;
- Error *err;
-
- /* All further fields are accessed only under mutex */
- bool running; /* thread is running now */
- bool detached; /* thread is detached and should cleanup the state */
-
- /*
- * wait_co: if non-NULL, which coroutine to wake in
- * nbd_co_establish_connection() after yield()
- */
- Coroutine *wait_co;
-} NBDClientConnection;
-
typedef struct BDRVNBDState {
QIOChannelSocket *sioc; /* The master data channel */
QIOChannel *ioc; /* The current I/O channel which may differ (eg TLS) */
@@ -126,12 +100,8 @@ typedef struct BDRVNBDState {
NBDClientConnection *conn;
} BDRVNBDState;
-static void nbd_client_connection_release(NBDClientConnection *conn);
static int nbd_establish_connection(BlockDriverState *bs, SocketAddress *saddr,
Error **errp);
-static coroutine_fn QIOChannelSocket *
-nbd_co_establish_connection(NBDClientConnection *conn, Error **errp);
-static void nbd_co_establish_connection_cancel(NBDClientConnection *conn);
static int nbd_client_handshake(BlockDriverState *bs, Error **errp);
static void nbd_yank(void *opaque);
@@ -344,182 +314,6 @@ static bool nbd_client_connecting_wait(BDRVNBDState *s)
return qatomic_load_acquire(&s->state) == NBD_CLIENT_CONNECTING_WAIT;
}
-static NBDClientConnection *
-nbd_client_connection_new(const SocketAddress *saddr)
-{
- NBDClientConnection *conn = g_new(NBDClientConnection, 1);
-
- *conn = (NBDClientConnection) {
- .saddr = QAPI_CLONE(SocketAddress, saddr),
- };
-
- qemu_mutex_init(&conn->mutex);
-
- return conn;
-}
-
-static void nbd_client_connection_do_free(NBDClientConnection *conn)
-{
- if (conn->sioc) {
- qio_channel_close(QIO_CHANNEL(conn->sioc), NULL);
- object_unref(OBJECT(conn->sioc));
- }
- error_free(conn->err);
- qapi_free_SocketAddress(conn->saddr);
- g_free(conn);
-}
-
-static void *connect_thread_func(void *opaque)
-{
- NBDClientConnection *conn = opaque;
- int ret;
- bool do_free;
-
- conn->sioc = qio_channel_socket_new();
-
- error_free(conn->err);
- conn->err = NULL;
- ret = qio_channel_socket_connect_sync(conn->sioc, conn->saddr, &conn->err);
- if (ret < 0) {
- object_unref(OBJECT(conn->sioc));
- conn->sioc = NULL;
- }
-
- qio_channel_set_delay(QIO_CHANNEL(conn->sioc), false);
-
- qemu_mutex_lock(&conn->mutex);
-
- assert(conn->running);
- conn->running = false;
- if (conn->wait_co) {
- aio_co_wake(conn->wait_co);
- conn->wait_co = NULL;
- }
- do_free = conn->detached;
-
- qemu_mutex_unlock(&conn->mutex);
-
- if (do_free) {
- nbd_client_connection_do_free(conn);
- }
-
- return NULL;
-}
-
-static void nbd_client_connection_release(NBDClientConnection *conn)
-{
- bool do_free = false;
-
- if (!conn) {
- return;
- }
-
- qemu_mutex_lock(&conn->mutex);
- assert(!conn->detached);
- if (conn->running) {
- conn->detached = true;
- } else {
- do_free = true;
- }
- qemu_mutex_unlock(&conn->mutex);
-
- if (do_free) {
- nbd_client_connection_do_free(conn);
- }
-}
-
-/*
- * Get a new connection in context of @conn:
- * if the thread is running, wait for completion
- * if the thread already succeeded in the background, and user didn't get the
- * result, just return it now
- * otherwise the thread is not running, so start a thread and wait for
- * completion
- */
-static coroutine_fn QIOChannelSocket *
-nbd_co_establish_connection(NBDClientConnection *conn, Error **errp)
-{
- QIOChannelSocket *sioc = NULL;
- QemuThread thread;
-
- qemu_mutex_lock(&conn->mutex);
-
- /*
- * Don't call nbd_co_establish_connection() in several coroutines in
- * parallel. Only one call at once is supported.
- */
- assert(!conn->wait_co);
-
- if (!conn->running) {
- if (conn->sioc) {
- /* Previous attempt finally succeeded in background */
- sioc = g_steal_pointer(&conn->sioc);
- qemu_mutex_unlock(&conn->mutex);
-
- return sioc;
- }
-
- conn->running = true;
- error_free(conn->err);
- conn->err = NULL;
- qemu_thread_create(&thread, "nbd-connect",
- connect_thread_func, conn, QEMU_THREAD_DETACHED);
- }
-
- conn->wait_co = qemu_coroutine_self();
-
- qemu_mutex_unlock(&conn->mutex);
-
- /*
- * We are going to wait for connect-thread finish, but
- * nbd_co_establish_connection_cancel() can interrupt.
- */
- qemu_coroutine_yield();
-
- qemu_mutex_lock(&conn->mutex);
-
- if (conn->running) {
- /*
- * The connection attempt was canceled and the coroutine resumed
- * before the connection thread finished its job. Report the
- * attempt as failed, but leave the connection thread running,
- * to reuse it for the next connection attempt.
- */
- error_setg(errp, "Connection attempt cancelled by other operation");
- } else {
- error_propagate(errp, conn->err);
- conn->err = NULL;
- sioc = g_steal_pointer(&conn->sioc);
- }
-
- qemu_mutex_unlock(&conn->mutex);
-
- return sioc;
-}
-
-/*
- * nbd_co_establish_connection_cancel
- * Cancel nbd_co_establish_connection() asynchronously.
- *
- * Note that this function neither directly stops the thread nor closes the
- * socket, but rather safely wakes nbd_co_establish_connection() which is
- * sleeping in yield()
- */
-static void nbd_co_establish_connection_cancel(NBDClientConnection *conn)
-{
- Coroutine *wait_co;
-
- qemu_mutex_lock(&conn->mutex);
-
- wait_co = g_steal_pointer(&conn->wait_co);
-
- qemu_mutex_unlock(&conn->mutex);
-
- if (wait_co) {
- aio_co_wake(wait_co);
- }
-}
-
static coroutine_fn void nbd_reconnect_attempt(BDRVNBDState *s)
{
int ret;
diff --git a/nbd/client-connection.c b/nbd/client-connection.c
new file mode 100644
index 0000000000..31a129bf11
--- /dev/null
+++ b/nbd/client-connection.c
@@ -0,0 +1,231 @@
+/*
+ * QEMU Block driver for NBD
+ *
+ * Copyright (c) 2021 Virtuozzo International GmbH.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+
+#include "block/nbd.h"
+
+#include "qapi/qapi-visit-sockets.h"
+#include "qapi/clone-visitor.h"
+
+struct NBDClientConnection {
+ /* Initialization constants */
+ SocketAddress *saddr; /* address to connect to */
+
+ QemuMutex mutex;
+
+ /*
+ * @sioc and @err present a result of connection attempt.
+ * While running is true, they are used only by thread, mutex locking is not
+ * needed. When thread is finished nbd_co_establish_connection steal these
+ * pointers under mutex.
+ */
+ QIOChannelSocket *sioc;
+ Error *err;
+
+ /* All further fields are accessed only under mutex */
+ bool running; /* thread is running now */
+ bool detached; /* thread is detached and should cleanup the state */
+
+ /*
+ * wait_co: if non-NULL, which coroutine to wake in
+ * nbd_co_establish_connection() after yield()
+ */
+ Coroutine *wait_co;
+};
+
+NBDClientConnection *nbd_client_connection_new(const SocketAddress *saddr)
+{
+ NBDClientConnection *conn = g_new(NBDClientConnection, 1);
+
+ *conn = (NBDClientConnection) {
+ .saddr = QAPI_CLONE(SocketAddress, saddr),
+ };
+
+ qemu_mutex_init(&conn->mutex);
+
+ return conn;
+}
+
+static void nbd_client_connection_do_free(NBDClientConnection *conn)
+{
+ if (conn->sioc) {
+ qio_channel_close(QIO_CHANNEL(conn->sioc), NULL);
+ object_unref(OBJECT(conn->sioc));
+ }
+ error_free(conn->err);
+ qapi_free_SocketAddress(conn->saddr);
+ g_free(conn);
+}
+
+static void *connect_thread_func(void *opaque)
+{
+ NBDClientConnection *conn = opaque;
+ int ret;
+ bool do_free;
+
+ conn->sioc = qio_channel_socket_new();
+
+ error_free(conn->err);
+ conn->err = NULL;
+ ret = qio_channel_socket_connect_sync(conn->sioc, conn->saddr, &conn->err);
+ if (ret < 0) {
+ object_unref(OBJECT(conn->sioc));
+ conn->sioc = NULL;
+ }
+
+ qio_channel_set_delay(QIO_CHANNEL(conn->sioc), false);
+
+ qemu_mutex_lock(&conn->mutex);
+
+ assert(conn->running);
+ conn->running = false;
+ if (conn->wait_co) {
+ aio_co_wake(conn->wait_co);
+ conn->wait_co = NULL;
+ }
+ do_free = conn->detached;
+
+ qemu_mutex_unlock(&conn->mutex);
+
+ if (do_free) {
+ nbd_client_connection_do_free(conn);
+ }
+
+ return NULL;
+}
+
+void nbd_client_connection_release(NBDClientConnection *conn)
+{
+ bool do_free = false;
+
+ if (!conn) {
+ return;
+ }
+
+ qemu_mutex_lock(&conn->mutex);
+ assert(!conn->detached);
+ if (conn->running) {
+ conn->detached = true;
+ } else {
+ do_free = true;
+ }
+ qemu_mutex_unlock(&conn->mutex);
+
+ if (do_free) {
+ nbd_client_connection_do_free(conn);
+ }
+}
+
+/*
+ * Get a new connection in context of @conn:
+ * if the thread is running, wait for completion
+ * if the thread already succeeded in the background, and user didn't get the
+ * result, just return it now
+ * otherwise the thread is not running, so start a thread and wait for
+ * completion
+ */
+QIOChannelSocket *coroutine_fn
+nbd_co_establish_connection(NBDClientConnection *conn, Error **errp)
+{
+ QIOChannelSocket *sioc = NULL;
+ QemuThread thread;
+
+ qemu_mutex_lock(&conn->mutex);
+
+ /*
+ * Don't call nbd_co_establish_connection() in several coroutines in
+ * parallel. Only one call at once is supported.
+ */
+ assert(!conn->wait_co);
+
+ if (!conn->running) {
+ if (conn->sioc) {
+ /* Previous attempt finally succeeded in background */
+ sioc = g_steal_pointer(&conn->sioc);
+ qemu_mutex_unlock(&conn->mutex);
+
+ return sioc;
+ }
+
+ conn->running = true;
+ error_free(conn->err);
+ conn->err = NULL;
+ qemu_thread_create(&thread, "nbd-connect",
+ connect_thread_func, conn, QEMU_THREAD_DETACHED);
+ }
+
+ conn->wait_co = qemu_coroutine_self();
+
+ qemu_mutex_unlock(&conn->mutex);
+
+ /*
+ * We are going to wait for connect-thread finish, but
+ * nbd_co_establish_connection_cancel() can interrupt.
+ */
+ qemu_coroutine_yield();
+
+ qemu_mutex_lock(&conn->mutex);
+
+ if (conn->running) {
+ /*
+ * The connection attempt was canceled and the coroutine resumed
+ * before the connection thread finished its job. Report the
+ * attempt as failed, but leave the connection thread running,
+ * to reuse it for the next connection attempt.
+ */
+ error_setg(errp, "Connection attempt cancelled by other operation");
+ } else {
+ error_propagate(errp, conn->err);
+ conn->err = NULL;
+ sioc = g_steal_pointer(&conn->sioc);
+ }
+
+ qemu_mutex_unlock(&conn->mutex);
+
+ return sioc;
+}
+
+/*
+ * nbd_co_establish_connection_cancel
+ * Cancel nbd_co_establish_connection() asynchronously.
+ *
+ * Note that this function neither directly stops the thread nor closes the
+ * socket, but rather safely wakes nbd_co_establish_connection() which is
+ * sleeping in yield()
+ */
+void nbd_co_establish_connection_cancel(NBDClientConnection *conn)
+{
+ Coroutine *wait_co;
+
+ qemu_mutex_lock(&conn->mutex);
+
+ wait_co = g_steal_pointer(&conn->wait_co);
+
+ qemu_mutex_unlock(&conn->mutex);
+
+ if (wait_co) {
+ aio_co_wake(wait_co);
+ }
+}
diff --git a/nbd/meson.build b/nbd/meson.build
index 2baaa36948..b26d70565e 100644
--- a/nbd/meson.build
+++ b/nbd/meson.build
@@ -1,5 +1,6 @@
block_ss.add(files(
'client.c',
+ 'client-connection.c',
'common.c',
))
blockdev_ss.add(files(
--
2.29.2
next prev parent reply other threads:[~2021-06-10 10:23 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-10 10:07 [PATCH v4 00/32] block/nbd: rework client connection Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 01/32] co-queue: drop extra coroutine_fn marks Vladimir Sementsov-Ogievskiy
2021-06-10 17:22 ` Eric Blake
2021-06-10 17:37 ` Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 02/32] block/nbd: fix channel object leak Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 03/32] block/nbd: fix how state is cleared on nbd_open() failure paths Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 04/32] block/nbd: connect_thread_func(): do qio_channel_set_delay(false) Vladimir Sementsov-Ogievskiy
2021-06-10 18:37 ` Eric Blake
2021-06-10 10:07 ` [PATCH v4 05/32] qemu-sockets: introduce socket_address_parse_named_fd() Vladimir Sementsov-Ogievskiy
2021-06-11 13:22 ` Eric Blake
2021-06-11 14:10 ` Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 06/32] block/nbd: call socket_address_parse_named_fd() in advance Vladimir Sementsov-Ogievskiy
2021-06-11 13:54 ` Eric Blake
2021-06-10 10:07 ` [PATCH v4 07/32] block/nbd: ensure ->connection_thread is always valid Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 08/32] block/nbd: nbd_client_handshake(): fix leak of s->ioc Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 09/32] block/nbd: BDRVNBDState: drop unused connect_err and connect_status Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 10/32] block/nbd: simplify waking of nbd_co_establish_connection() Vladimir Sementsov-Ogievskiy
2021-06-11 14:06 ` Eric Blake
2021-06-10 10:07 ` [PATCH v4 11/32] block/nbd: drop thr->state Vladimir Sementsov-Ogievskiy
2021-06-11 14:25 ` Eric Blake
2021-06-10 10:07 ` [PATCH v4 12/32] block/nbd: bs-independent interface for nbd_co_establish_connection() Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 13/32] block/nbd: make nbd_co_establish_connection_cancel() bs-independent Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 14/32] block/nbd: rename NBDConnectThread to NBDClientConnection Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 15/32] block/nbd: introduce nbd_client_connection_new() Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 16/32] block/nbd: introduce nbd_client_connection_release() Vladimir Sementsov-Ogievskiy
2021-06-11 14:28 ` Eric Blake
2021-06-10 10:07 ` Vladimir Sementsov-Ogievskiy [this message]
2021-06-10 10:07 ` [PATCH v4 18/32] nbd/client-connection: use QEMU_LOCK_GUARD Vladimir Sementsov-Ogievskiy
2021-06-11 14:31 ` Eric Blake
2021-06-10 10:07 ` [PATCH v4 19/32] nbd/client-connection: add possibility of negotiation Vladimir Sementsov-Ogievskiy
2021-06-11 15:07 ` Eric Blake
2021-06-10 10:07 ` [PATCH v4 20/32] nbd/client-connection: implement connection retry Vladimir Sementsov-Ogievskiy
2021-06-11 15:12 ` Eric Blake
2021-11-22 16:30 ` Eric Blake
2021-11-22 17:17 ` Vladimir Sementsov-Ogievskiy
2021-11-22 21:51 ` Eric Blake
2021-06-10 10:07 ` [PATCH v4 21/32] nbd/client-connection: shutdown connection on release Vladimir Sementsov-Ogievskiy
2021-06-11 15:27 ` Eric Blake
2021-06-10 10:07 ` [PATCH v4 22/32] block/nbd: split nbd_handle_updated_info out of nbd_client_handshake() Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 23/32] block/nbd: use negotiation of NBDClientConnection Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 24/32] block/nbd: don't touch s->sioc in nbd_teardown_connection() Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 25/32] block/nbd: drop BDRVNBDState::sioc Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 26/32] nbd/client-connection: return only one io channel Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 27/32] block-coroutine-wrapper: allow non bdrv_ prefix Vladimir Sementsov-Ogievskiy
2021-06-10 10:07 ` [PATCH v4 28/32] block/nbd: split nbd_co_do_establish_connection out of nbd_reconnect_attempt Vladimir Sementsov-Ogievskiy
2021-06-11 15:29 ` Eric Blake
2021-06-10 10:07 ` [PATCH v4 29/32] nbd/client-connection: add option for non-blocking connection attempt Vladimir Sementsov-Ogievskiy
2021-06-10 10:08 ` [PATCH v4 30/32] block/nbd: reuse nbd_co_do_establish_connection() in nbd_open() Vladimir Sementsov-Ogievskiy
2021-06-10 10:08 ` [PATCH v4 31/32] block/nbd: add nbd_client_connected() helper Vladimir Sementsov-Ogievskiy
2021-06-10 10:08 ` [PATCH v4 32/32] block/nbd: safer transition to receiving request Vladimir Sementsov-Ogievskiy
2021-06-11 15:55 ` [PATCH v4 00/32] block/nbd: rework client connection Eric Blake
2021-06-11 17:23 ` Vladimir Sementsov-Ogievskiy
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