From patchwork Tue May 16 15:54:15 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Cody X-Patchwork-Id: 9729323 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7B947602DB for ; Tue, 16 May 2017 15:58:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6DC592893E for ; Tue, 16 May 2017 15:58:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 62AA3289E5; Tue, 16 May 2017 15:58:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 03BAC2893E for ; Tue, 16 May 2017 15:58:28 +0000 (UTC) Received: from localhost ([::1]:42900 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dAerk-0005y5-65 for patchwork-qemu-devel@patchwork.kernel.org; Tue, 16 May 2017 11:58:28 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46779) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dAeoC-0003U8-CC for qemu-devel@nongnu.org; Tue, 16 May 2017 11:54:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dAeoB-0001dU-C7 for qemu-devel@nongnu.org; Tue, 16 May 2017 11:54:48 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52956) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dAeo8-0001a5-3s; Tue, 16 May 2017 11:54:44 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A6AFD37E72; Tue, 16 May 2017 15:54:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com A6AFD37E72 Authentication-Results: ext-mx05.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx05.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=jcody@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com A6AFD37E72 Received: from localhost (ovpn-116-10.phx2.redhat.com [10.3.116.10]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3EF09A92AD; Tue, 16 May 2017 15:54:27 +0000 (UTC) From: Jeff Cody To: qemu-block@nongnu.org Date: Tue, 16 May 2017 11:54:15 -0400 Message-Id: <20170516155420.10106-4-jcody@redhat.com> In-Reply-To: <20170516155420.10106-1-jcody@redhat.com> References: <20170516155420.10106-1-jcody@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Tue, 16 May 2017 15:54:38 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 3/8] 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: peter.maydell@linaro.org, jcody@redhat.com, qemu-stable@nongnu.org, qemu-devel@nongnu.org, Paolo Bonzini Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP 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 --- block/curl.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/block/curl.c b/block/curl.c index 562340f..18b82bc 100644 --- a/block/curl.c +++ b/block/curl.c @@ -148,6 +148,7 @@ 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; @@ -164,6 +165,7 @@ 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) { @@ -213,6 +215,7 @@ 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; @@ -227,6 +230,7 @@ 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); @@ -265,7 +269,9 @@ 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; } @@ -306,8 +312,6 @@ 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; } @@ -854,8 +858,8 @@ 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: