From patchwork Tue Aug 29 00:14:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Roth X-Patchwork-Id: 806838 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3xh8pX2DKzz9sNr for ; Tue, 29 Aug 2017 10:36:52 +1000 (AEST) Received: from localhost ([::1]:41997 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dmUWQ-0002qM-3r for incoming@patchwork.ozlabs.org; Mon, 28 Aug 2017 20:36:50 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47804) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dmUCL-000162-7n for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:16:07 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dmUCI-0005J6-0I for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:16:05 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:32792 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dmUCH-0005IC-PX for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:16:01 -0400 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v7T0EBme044267 for ; Mon, 28 Aug 2017 20:16:01 -0400 Received: from e35.co.us.ibm.com (e35.co.us.ibm.com [32.97.110.153]) by mx0a-001b2d01.pphosted.com with ESMTP id 2cmu3kpe34-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 28 Aug 2017 20:16:01 -0400 Received: from localhost by e35.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Mon, 28 Aug 2017 18:15:57 -0600 Received: from b03ledav006.gho.boulder.ibm.com (b03ledav006.gho.boulder.ibm.com [9.17.130.237]) by b03cxnp08028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v7T0FvpG32047138; Mon, 28 Aug 2017 17:15:57 -0700 Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3C34FC603C; Mon, 28 Aug 2017 18:15:57 -0600 (MDT) Received: from localhost (unknown [9.80.85.217]) by b03ledav006.gho.boulder.ibm.com (Postfix) with ESMTP id 09073C6037; Mon, 28 Aug 2017 18:15:56 -0600 (MDT) From: Michael Roth To: qemu-devel@nongnu.org Date: Mon, 28 Aug 2017 19:14:04 -0500 X-Mailer: git-send-email 2.7.4 In-Reply-To: <1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17082900-0012-0000-0000-000014ECDC35 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007630; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000226; SDB=6.00909027; UDB=6.00455849; IPR=6.00689279; BA=6.00005557; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00016909; XFM=3.00000015; UTC=2017-08-29 00:15:59 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17082900-0013-0000-0000-00004F43FAF5 Message-Id: <1503965694-10794-30-git-send-email-mdroth@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-08-28_13:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000 definitions=main-1708290001 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.158.5 Subject: [Qemu-devel] [PATCH 29/79] curl: never invoke callbacks with s->mutex held X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Jeff Cody , qemu-stable@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Paolo Bonzini All curl callbacks go through curl_multi_do, and hence are called with s->mutex held. Note that with comments, and make curl_read_cb drop the lock before invoking the callback. Likewise for curl_find_buf, where the callback can be invoked by the caller. Cc: qemu-stable@nongnu.org Reviewed-by: Jeff Cody Signed-off-by: Paolo Bonzini Reviewed-by: Max Reitz Message-id: 20170515100059.15795-3-pbonzini@redhat.com Signed-off-by: Jeff Cody (cherry picked from commit 34db05e7ffe8d61ca7288b9532ad6e8300853318) Signed-off-by: Michael Roth --- block/curl.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/block/curl.c b/block/curl.c index c6dc4c0..59e69c6 100644 --- a/block/curl.c +++ b/block/curl.c @@ -147,6 +147,7 @@ static void curl_multi_do(void *arg); static void curl_multi_read(void *arg); #ifdef NEED_CURL_TIMER_CALLBACK +/* Called from curl_multi_do_locked, with s->mutex held. */ static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque) { BDRVCURLState *s = opaque; @@ -163,6 +164,7 @@ static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque) } #endif +/* Called from curl_multi_do_locked, with s->mutex held. */ static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action, void *userp, void *sp) { @@ -212,6 +214,7 @@ static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action, return 0; } +/* Called from curl_multi_do_locked, with s->mutex held. */ static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque) { BDRVCURLState *s = opaque; @@ -226,6 +229,7 @@ static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque) return realsize; } +/* Called from curl_multi_do_locked, with s->mutex held. */ static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque) { CURLState *s = ((CURLState*)opaque); @@ -264,7 +268,9 @@ static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque) request_length - offset); } + qemu_mutex_unlock(&s->s->mutex); acb->common.cb(acb->common.opaque, 0); + qemu_mutex_lock(&s->s->mutex); qemu_aio_unref(acb); s->acb[i] = NULL; } @@ -305,8 +311,6 @@ static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len, if (clamped_len < len) { qemu_iovec_memset(acb->qiov, clamped_len, 0, len - clamped_len); } - acb->common.cb(acb->common.opaque, 0); - return FIND_RET_OK; } @@ -832,8 +836,8 @@ static void curl_readv_bh_cb(void *p) // we can just call the callback and be done. switch (curl_find_buf(s, start, acb->nb_sectors * BDRV_SECTOR_SIZE, acb)) { case FIND_RET_OK: - qemu_aio_unref(acb); - // fall through + ret = 0; + goto out; case FIND_RET_WAIT: goto out; default: