From patchwork Fri Sep 29 14:51:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 1841373 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=Vp+/SWtq; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4RxtfN3gR3z1ypT for ; Sat, 30 Sep 2023 00:54:20 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qmErY-000625-Jr; Fri, 29 Sep 2023 10:53:04 -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 1qmErW-00060d-Uo for qemu-devel@nongnu.org; Fri, 29 Sep 2023 10:53:02 -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 1qmEr5-0004nd-1V for qemu-devel@nongnu.org; Fri, 29 Sep 2023 10:53:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1695999154; 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=J3CC/EHMC+Dtjb49wgDQhSUo+x3pKgqB9hYH/hX3Z0A=; b=Vp+/SWtq2gjaQJQnYnxQJ36KQZ/QzuZrroBc8rWeeo/D+tYBOi485he0HG6XCcdDyAsUPG LpynX+M8mPH84E8629HZc2FwkwA5Uess4hIAD9cU7XyGWnNE/QwkPhQwHnB5vNB5ysmcXA HEkdtAMP+Q6sRp9zix5jHonSdkw2hDQ= 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-687-Uf7bZHpnOQOez9XEZvEksw-1; Fri, 29 Sep 2023 10:52:29 -0400 X-MC-Unique: Uf7bZHpnOQOez9XEZvEksw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (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 6E3ED3800EB8; Fri, 29 Sep 2023 14:52:29 +0000 (UTC) Received: from merkur.fritz.box (unknown [10.39.193.159]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3EA402026D4B; Fri, 29 Sep 2023 14:52:28 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, stefanha@redhat.com, eesposit@redhat.com, eblake@redhat.com, pbonzini@redhat.com, vsementsov@yandex-team.ru, qemu-devel@nongnu.org Subject: [PATCH 18/22] block: Mark bdrv_apply_auto_read_only() and callers GRAPH_RDLOCK Date: Fri, 29 Sep 2023 16:51:53 +0200 Message-ID: <20230929145157.45443-19-kwolf@redhat.com> In-Reply-To: <20230929145157.45443-1-kwolf@redhat.com> References: <20230929145157.45443-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 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: 12 X-Spam_score: 1.2 X-Spam_bar: + X-Spam_report: (1.2 / 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, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_apply_auto_read_only() need to hold a reader lock for the graph because it calls bdrv_can_set_read_only(), which indirectly accesses the parents list of a node. Signed-off-by: Kevin Wolf --- include/block/block-io.h | 6 ++++-- block.c | 4 ++-- block/bochs.c | 2 ++ block/cloop.c | 2 ++ block/curl.c | 2 ++ block/dmg.c | 2 ++ block/gluster.c | 2 ++ block/iscsi.c | 2 ++ block/nbd.c | 3 ++- block/rbd.c | 2 ++ 10 files changed, 22 insertions(+), 5 deletions(-) diff --git a/include/block/block-io.h b/include/block/block-io.h index 5b1a1d5998..13cc756ed8 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -156,8 +156,10 @@ int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, int coroutine_fn GRAPH_RDLOCK bdrv_co_is_zero_fast(BlockDriverState *bs, int64_t offset, int64_t bytes); -int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, - Error **errp); +int GRAPH_RDLOCK +bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, + Error **errp); + bool bdrv_is_read_only(BlockDriverState *bs); bool bdrv_is_writable(BlockDriverState *bs); bool bdrv_is_sg(BlockDriverState *bs); diff --git a/block.c b/block.c index 0814b0704e..3178c1d819 100644 --- a/block.c +++ b/block.c @@ -320,8 +320,6 @@ int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, int ret = 0; IO_CODE(); - assume_graph_lock(); /* FIXME */ - if (!(bs->open_flags & BDRV_O_RDWR)) { return 0; } @@ -1908,7 +1906,9 @@ static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file, if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, ro)) { if (!ro && bdrv_is_whitelisted(drv, true)) { + bdrv_graph_rdlock_main_loop(); ret = bdrv_apply_auto_read_only(bs, NULL, NULL); + bdrv_graph_rdunlock_main_loop(); } else { ret = -ENOTSUP; } diff --git a/block/bochs.c b/block/bochs.c index 66e7a58e5e..8c659fa9b9 100644 --- a/block/bochs.c +++ b/block/bochs.c @@ -106,7 +106,9 @@ static int bochs_open(BlockDriverState *bs, QDict *options, int flags, int ret; /* No write support yet */ + bdrv_graph_rdlock_main_loop(); ret = bdrv_apply_auto_read_only(bs, NULL, errp); + bdrv_graph_rdunlock_main_loop(); if (ret < 0) { return ret; } diff --git a/block/cloop.c b/block/cloop.c index 835a0fe3da..773d7918be 100644 --- a/block/cloop.c +++ b/block/cloop.c @@ -67,7 +67,9 @@ static int cloop_open(BlockDriverState *bs, QDict *options, int flags, uint32_t offsets_size, max_compressed_block_size = 1, i; int ret; + bdrv_graph_rdlock_main_loop(); ret = bdrv_apply_auto_read_only(bs, NULL, errp); + bdrv_graph_rdunlock_main_loop(); if (ret < 0) { return ret; } diff --git a/block/curl.c b/block/curl.c index 0fc42d03d7..419f7c89ef 100644 --- a/block/curl.c +++ b/block/curl.c @@ -696,8 +696,10 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags, const char *protocol_delimiter; int ret; + bdrv_graph_rdlock_main_loop(); ret = bdrv_apply_auto_read_only(bs, "curl driver does not support writes", errp); + bdrv_graph_rdunlock_main_loop(); if (ret < 0) { return ret; } diff --git a/block/dmg.c b/block/dmg.c index 06a0244a9c..38ee72bbe5 100644 --- a/block/dmg.c +++ b/block/dmg.c @@ -452,7 +452,9 @@ static int dmg_open(BlockDriverState *bs, QDict *options, int flags, int64_t offset; int ret; + bdrv_graph_rdlock_main_loop(); ret = bdrv_apply_auto_read_only(bs, NULL, errp); + bdrv_graph_rdunlock_main_loop(); if (ret < 0) { return ret; } diff --git a/block/gluster.c b/block/gluster.c index ad5fadbe79..cc74af06dc 100644 --- a/block/gluster.c +++ b/block/gluster.c @@ -863,11 +863,13 @@ static int qemu_gluster_open(BlockDriverState *bs, QDict *options, if (ret == -EACCES || ret == -EROFS) { /* Try to degrade to read-only, but if it doesn't work, still use the * normal error message. */ + bdrv_graph_rdlock_main_loop(); if (bdrv_apply_auto_read_only(bs, NULL, NULL) == 0) { open_flags = (open_flags & ~O_RDWR) | O_RDONLY; s->fd = glfs_open(s->glfs, gconf->path, open_flags); ret = s->fd ? 0 : -errno; } + bdrv_graph_rdunlock_main_loop(); } s->supports_seek_data = qemu_gluster_test_seek(s->fd); diff --git a/block/iscsi.c b/block/iscsi.c index 5640c8b565..2ff14b7472 100644 --- a/block/iscsi.c +++ b/block/iscsi.c @@ -1925,7 +1925,9 @@ static int iscsi_open(BlockDriverState *bs, QDict *options, int flags, /* Check the write protect flag of the LUN if we want to write */ if (iscsilun->type == TYPE_DISK && (flags & BDRV_O_RDWR) && iscsilun->write_protected) { + bdrv_graph_rdlock_main_loop(); ret = bdrv_apply_auto_read_only(bs, "LUN is write protected", errp); + bdrv_graph_rdunlock_main_loop(); if (ret < 0) { goto out; } diff --git a/block/nbd.c b/block/nbd.c index cc48580df7..2236a5a3a9 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -275,7 +275,8 @@ static bool nbd_client_will_reconnect(BDRVNBDState *s) * Return failure if the server's advertised options are incompatible with the * client's needs. */ -static int nbd_handle_updated_info(BlockDriverState *bs, Error **errp) +static int coroutine_fn GRAPH_RDLOCK +nbd_handle_updated_info(BlockDriverState *bs, Error **errp) { BDRVNBDState *s = (BDRVNBDState *)bs->opaque; int ret; diff --git a/block/rbd.c b/block/rbd.c index f2defad9da..d23e6d6b80 100644 --- a/block/rbd.c +++ b/block/rbd.c @@ -1168,7 +1168,9 @@ static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags, /* If we are using an rbd snapshot, we must be r/o, otherwise * leave as-is */ if (s->snap != NULL) { + bdrv_graph_rdlock_main_loop(); r = bdrv_apply_auto_read_only(bs, "rbd snapshots are read-only", errp); + bdrv_graph_rdunlock_main_loop(); if (r < 0) { goto failed_post_open; }