From patchwork Mon Sep 11 09:46:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 13379048 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CE1D7EE7FF4 for ; Mon, 11 Sep 2023 09:48:08 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qfdVP-0005tE-1E; Mon, 11 Sep 2023 05:46:55 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qfdVN-0005sX-Us for qemu-devel@nongnu.org; Mon, 11 Sep 2023 05:46:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qfdVL-0004hS-9v for qemu-devel@nongnu.org; Mon, 11 Sep 2023 05:46:53 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694425610; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8AY7uUmyzFtYjdjEQ61hcK8Ez6IosZqYWRHIymRaVFQ=; b=JgEgMQ8g9faZuceSEVY82w2KAWuhU311VzCj8EscCUQIHgFiiexztUuMZ1SoWlEtXkz8ht oBVbC6Ecjaa9pP/4pyzTGLvWldNEA2AibrPlCRsC7/ieMIzvWPY+VWocDnK0EXcBozEUof XEAlcql1+MXiCPpY4EQ+6nR4DO3qupE= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-171-Vav7obErO3eMHK-eZxzzcw-1; Mon, 11 Sep 2023 05:46:49 -0400 X-MC-Unique: Vav7obErO3eMHK-eZxzzcw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 0FD6938117E9; Mon, 11 Sep 2023 09:46:49 +0000 (UTC) Received: from merkur.redhat.com (unknown [10.39.192.243]) by smtp.corp.redhat.com (Postfix) with ESMTP id D428B40C6EA8; Mon, 11 Sep 2023 09:46:47 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, stefanha@redhat.com, eblake@redhat.com, eesposit@redhat.com, pbonzini@redhat.com, vsementsov@yandex-team.ru, qemu-devel@nongnu.org Subject: [PATCH v2 12/21] block: Mark bdrv_attach_child() GRAPH_WRLOCK Date: Mon, 11 Sep 2023 11:46:11 +0200 Message-ID: <20230911094620.45040-13-kwolf@redhat.com> In-Reply-To: <20230911094620.45040-1-kwolf@redhat.com> References: <20230911094620.45040-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Received-SPF: pass client-ip=170.10.129.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Instead of taking the writer lock internally, require callers to already hold it when calling bdrv_attach_child_common(). These callers will typically already hold the graph lock once the locking work is completed, which means that they can't call functions that take it internally. Signed-off-by: Kevin Wolf Reviewed-by: Emanuele Giuseppe Esposito Reviewed-by: Stefan Hajnoczi --- include/block/block-global-state.h | 14 ++++++++------ block.c | 7 +++---- block/quorum.c | 2 ++ block/replication.c | 6 ++++++ tests/unit/test-bdrv-drain.c | 14 ++++++++++++++ tests/unit/test-bdrv-graph-mod.c | 10 ++++++++++ 6 files changed, 43 insertions(+), 10 deletions(-) diff --git a/include/block/block-global-state.h b/include/block/block-global-state.h index e570799f85..eb12a35439 100644 --- a/include/block/block-global-state.h +++ b/include/block/block-global-state.h @@ -226,12 +226,14 @@ void no_coroutine_fn bdrv_unref(BlockDriverState *bs); void coroutine_fn no_co_wrapper bdrv_co_unref(BlockDriverState *bs); void GRAPH_WRLOCK bdrv_schedule_unref(BlockDriverState *bs); void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); -BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, - BlockDriverState *child_bs, - const char *child_name, - const BdrvChildClass *child_class, - BdrvChildRole child_role, - Error **errp); + +BdrvChild * GRAPH_WRLOCK +bdrv_attach_child(BlockDriverState *parent_bs, + BlockDriverState *child_bs, + const char *child_name, + const BdrvChildClass *child_class, + BdrvChildRole child_role, + Error **errp); bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); diff --git a/block.c b/block.c index f06de58a3b..369023872a 100644 --- a/block.c +++ b/block.c @@ -3219,8 +3219,6 @@ BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, GLOBAL_STATE_CODE(); - bdrv_graph_wrlock(child_bs); - child = bdrv_attach_child_noperm(parent_bs, child_bs, child_name, child_class, child_role, tran, errp); if (!child) { @@ -3235,9 +3233,8 @@ BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, out: tran_finalize(tran, ret); - bdrv_graph_wrunlock(); - bdrv_unref(child_bs); + bdrv_schedule_unref(child_bs); return ret < 0 ? NULL : child; } @@ -3758,11 +3755,13 @@ BdrvChild *bdrv_open_child(const char *filename, return NULL; } + bdrv_graph_wrlock(NULL); ctx = bdrv_get_aio_context(bs); aio_context_acquire(ctx); child = bdrv_attach_child(parent, bs, bdref_key, child_class, child_role, errp); aio_context_release(ctx); + bdrv_graph_wrunlock(); return child; } diff --git a/block/quorum.c b/block/quorum.c index f28758cf2b..def0539fda 100644 --- a/block/quorum.c +++ b/block/quorum.c @@ -1094,8 +1094,10 @@ static void quorum_add_child(BlockDriverState *bs, BlockDriverState *child_bs, /* We can safely add the child now */ bdrv_ref(child_bs); + bdrv_graph_wrlock(child_bs); child = bdrv_attach_child(bs, child_bs, indexstr, &child_of_bds, BDRV_CHILD_DATA, errp); + bdrv_graph_wrunlock(); if (child == NULL) { s->next_child_index--; goto out; diff --git a/block/replication.c b/block/replication.c index ea4bf1aa80..eec9819625 100644 --- a/block/replication.c +++ b/block/replication.c @@ -542,12 +542,15 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, return; } + bdrv_graph_wrlock(bs); + bdrv_ref(hidden_disk->bs); s->hidden_disk = bdrv_attach_child(bs, hidden_disk->bs, "hidden disk", &child_of_bds, BDRV_CHILD_DATA, &local_err); if (local_err) { error_propagate(errp, local_err); + bdrv_graph_wrunlock(); aio_context_release(aio_context); return; } @@ -558,10 +561,13 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, BDRV_CHILD_DATA, &local_err); if (local_err) { error_propagate(errp, local_err); + bdrv_graph_wrunlock(); aio_context_release(aio_context); return; } + bdrv_graph_wrunlock(); + /* start backup job now */ error_setg(&s->blocker, "Block device is in use by internal backup job"); diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index 89c8fa6780..6d33249656 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -1055,8 +1055,10 @@ static void do_test_delete_by_drain(bool detach_instead_of_delete, null_bs = bdrv_open("null-co://", NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, &error_abort); + bdrv_graph_wrlock(NULL); bdrv_attach_child(bs, null_bs, "null-child", &child_of_bds, BDRV_CHILD_DATA, &error_abort); + bdrv_graph_wrunlock(); /* This child will be the one to pass to requests through to, and * it will stall until a drain occurs */ @@ -1064,17 +1066,21 @@ static void do_test_delete_by_drain(bool detach_instead_of_delete, &error_abort); child_bs->total_sectors = 65536 >> BDRV_SECTOR_BITS; /* Takes our reference to child_bs */ + bdrv_graph_wrlock(NULL); tts->wait_child = bdrv_attach_child(bs, child_bs, "wait-child", &child_of_bds, BDRV_CHILD_DATA | BDRV_CHILD_PRIMARY, &error_abort); + bdrv_graph_wrunlock(); /* This child is just there to be deleted * (for detach_instead_of_delete == true) */ null_bs = bdrv_open("null-co://", NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, &error_abort); + bdrv_graph_wrlock(NULL); bdrv_attach_child(bs, null_bs, "null-child", &child_of_bds, BDRV_CHILD_DATA, &error_abort); + bdrv_graph_wrunlock(); blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); blk_insert_bs(blk, bs, &error_abort); @@ -1159,9 +1165,11 @@ static void detach_indirect_bh(void *opaque) bdrv_unref_child(data->parent_b, data->child_b); bdrv_ref(data->c); + bdrv_graph_wrlock(NULL); data->child_c = bdrv_attach_child(data->parent_b, data->c, "PB-C", &child_of_bds, BDRV_CHILD_DATA, &error_abort); + bdrv_graph_wrunlock(); } static void detach_by_parent_aio_cb(void *opaque, int ret) @@ -1258,6 +1266,7 @@ static void test_detach_indirect(bool by_parent_cb) /* Set child relationships */ bdrv_ref(b); bdrv_ref(a); + bdrv_graph_wrlock(NULL); child_b = bdrv_attach_child(parent_b, b, "PB-B", &child_of_bds, BDRV_CHILD_DATA, &error_abort); child_a = bdrv_attach_child(parent_b, a, "PB-A", &child_of_bds, @@ -1267,6 +1276,7 @@ static void test_detach_indirect(bool by_parent_cb) bdrv_attach_child(parent_a, a, "PA-A", by_parent_cb ? &child_of_bds : &detach_by_driver_cb_class, BDRV_CHILD_DATA, &error_abort); + bdrv_graph_wrunlock(); g_assert_cmpint(parent_a->refcnt, ==, 1); g_assert_cmpint(parent_b->refcnt, ==, 1); @@ -1685,6 +1695,7 @@ static void test_drop_intermediate_poll(void) * Establish the chain last, so the chain links are the first * elements in the BDS.parents lists */ + bdrv_graph_wrlock(NULL); for (i = 0; i < 3; i++) { if (i) { /* Takes the reference to chain[i - 1] */ @@ -1692,6 +1703,7 @@ static void test_drop_intermediate_poll(void) &chain_child_class, BDRV_CHILD_COW, &error_abort); } } + bdrv_graph_wrunlock(); job = block_job_create("job", &test_simple_job_driver, NULL, job_node, 0, BLK_PERM_ALL, 0, 0, NULL, NULL, &error_abort); @@ -1936,8 +1948,10 @@ static void do_test_replace_child_mid_drain(int old_drain_count, new_child_bs->total_sectors = 1; bdrv_ref(old_child_bs); + bdrv_graph_wrlock(NULL); bdrv_attach_child(parent_bs, old_child_bs, "child", &child_of_bds, BDRV_CHILD_COW, &error_abort); + bdrv_graph_wrunlock(); parent_s->setup_completed = true; for (i = 0; i < old_drain_count; i++) { diff --git a/tests/unit/test-bdrv-graph-mod.c b/tests/unit/test-bdrv-graph-mod.c index d8503165b3..621e616655 100644 --- a/tests/unit/test-bdrv-graph-mod.c +++ b/tests/unit/test-bdrv-graph-mod.c @@ -137,8 +137,10 @@ static void test_update_perm_tree(void) blk_insert_bs(root, bs, &error_abort); + bdrv_graph_wrlock(NULL); bdrv_attach_child(filter, bs, "child", &child_of_bds, BDRV_CHILD_DATA, &error_abort); + bdrv_graph_wrunlock(); aio_context_acquire(qemu_get_aio_context()); ret = bdrv_append(filter, bs, NULL); @@ -205,8 +207,10 @@ static void test_should_update_child(void) bdrv_set_backing_hd(target, bs, &error_abort); g_assert(target->backing->bs == bs); + bdrv_graph_wrlock(NULL); bdrv_attach_child(filter, target, "target", &child_of_bds, BDRV_CHILD_DATA, &error_abort); + bdrv_graph_wrunlock(); aio_context_acquire(qemu_get_aio_context()); bdrv_append(filter, bs, &error_abort); aio_context_release(qemu_get_aio_context()); @@ -236,6 +240,7 @@ static void test_parallel_exclusive_write(void) */ bdrv_ref(base); + bdrv_graph_wrlock(NULL); bdrv_attach_child(top, fl1, "backing", &child_of_bds, BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, &error_abort); @@ -245,6 +250,7 @@ static void test_parallel_exclusive_write(void) bdrv_attach_child(fl2, base, "backing", &child_of_bds, BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, &error_abort); + bdrv_graph_wrunlock(); bdrv_replace_node(fl1, fl2, &error_abort); @@ -349,6 +355,7 @@ static void test_parallel_perm_update(void) */ bdrv_ref(base); + bdrv_graph_wrlock(NULL); bdrv_attach_child(top, ws, "file", &child_of_bds, BDRV_CHILD_DATA, &error_abort); c_fl1 = bdrv_attach_child(ws, fl1, "first", &child_of_bds, @@ -361,6 +368,7 @@ static void test_parallel_perm_update(void) bdrv_attach_child(fl2, base, "backing", &child_of_bds, BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, &error_abort); + bdrv_graph_wrunlock(); /* Select fl1 as first child to be active */ s->selected = c_fl1; @@ -410,9 +418,11 @@ static void test_append_greedy_filter(void) BlockDriverState *base = no_perm_node("base"); BlockDriverState *fl = exclusive_writer_node("fl1"); + bdrv_graph_wrlock(NULL); bdrv_attach_child(top, base, "backing", &child_of_bds, BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, &error_abort); + bdrv_graph_wrunlock(); aio_context_acquire(qemu_get_aio_context()); bdrv_append(fl, base, &error_abort);