From nobody Sun Nov 2 11:45:10 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1527573998554205.803120657372; Mon, 28 May 2018 23:06:38 -0700 (PDT) Received: from localhost ([::1]:59096 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fNXm9-0001tU-4O for importer@patchew.org; Tue, 29 May 2018 02:06:29 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58829) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fNXea-0004dA-SJ for qemu-devel@nongnu.org; Tue, 29 May 2018 01:58:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fNXeW-0001U5-Rs for qemu-devel@nongnu.org; Tue, 29 May 2018 01:58:40 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:52730 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fNXeW-0001Tq-MT for qemu-devel@nongnu.org; Tue, 29 May 2018 01:58:36 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 36F5A401EF08 for ; Tue, 29 May 2018 05:58:36 +0000 (UTC) Received: from xz-mi.nay.redhat.com (dhcp-14-151.nay.redhat.com [10.66.14.151]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5495B42227; Tue, 29 May 2018 05:58:33 +0000 (UTC) From: Peter Xu To: qemu-devel@nongnu.org Date: Tue, 29 May 2018 13:57:55 +0800 Message-Id: <20180529055755.12404-8-peterx@redhat.com> In-Reply-To: <20180529055755.12404-1-peterx@redhat.com> References: <20180529055755.12404-1-peterx@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 29 May 2018 05:58:36 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 29 May 2018 05:58:36 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'peterx@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v9 7/7] monitor: add lock to protect mon_fdsets 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: Markus Armbruster , peterx@redhat.com, "Dr . David Alan Gilbert" , Stefan Hajnoczi , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Introduce a new global big lock for mon_fdsets. Take it where needed. The monitor_fdset_get_fd() handling is a bit tricky: now we need to call qemu_mutex_unlock() which might pollute errno, so we need to make sure the correct errno be passed up to the callers. To make things simpler, we let monitor_fdset_get_fd() return the -errno directly when error happens, then in qemu_open() we move it back into errno. Signed-off-by: Peter Xu Reviewed-by: Markus Armbruster Reviewed-by: Stefan Hajnoczi --- monitor.c | 52 +++++++++++++++++++++++++++++++++++++++++---------- stubs/fdset.c | 2 +- util/osdep.c | 3 ++- 3 files changed, 45 insertions(+), 12 deletions(-) diff --git a/monitor.c b/monitor.c index bd9ab5597f..09902a58d5 100644 --- a/monitor.c +++ b/monitor.c @@ -272,7 +272,10 @@ static QemuMutex monitor_lock; static GHashTable *monitor_qapi_event_state; static QTAILQ_HEAD(mon_list, Monitor) mon_list; =20 +/* Protects mon_fdsets */ +static QemuMutex mon_fdsets_lock; static QLIST_HEAD(mon_fdsets, MonFdset) mon_fdsets; + static int mon_refcount; =20 static mon_cmd_t mon_cmds[]; @@ -2317,9 +2320,11 @@ static void monitor_fdsets_cleanup(void) MonFdset *mon_fdset; MonFdset *mon_fdset_next; =20 + qemu_mutex_lock(&mon_fdsets_lock); QLIST_FOREACH_SAFE(mon_fdset, &mon_fdsets, next, mon_fdset_next) { monitor_fdset_cleanup(mon_fdset); } + qemu_mutex_unlock(&mon_fdsets_lock); } =20 AddfdInfo *qmp_add_fd(bool has_fdset_id, int64_t fdset_id, bool has_opaque, @@ -2354,6 +2359,7 @@ void qmp_remove_fd(int64_t fdset_id, bool has_fd, int= 64_t fd, Error **errp) MonFdsetFd *mon_fdset_fd; char fd_str[60]; =20 + qemu_mutex_lock(&mon_fdsets_lock); QLIST_FOREACH(mon_fdset, &mon_fdsets, next) { if (mon_fdset->id !=3D fdset_id) { continue; @@ -2373,10 +2379,12 @@ void qmp_remove_fd(int64_t fdset_id, bool has_fd, i= nt64_t fd, Error **errp) goto error; } monitor_fdset_cleanup(mon_fdset); + qemu_mutex_unlock(&mon_fdsets_lock); return; } =20 error: + qemu_mutex_unlock(&mon_fdsets_lock); if (has_fd) { snprintf(fd_str, sizeof(fd_str), "fdset-id:%" PRId64 ", fd:%" PRId= 64, fdset_id, fd); @@ -2392,6 +2400,7 @@ FdsetInfoList *qmp_query_fdsets(Error **errp) MonFdsetFd *mon_fdset_fd; FdsetInfoList *fdset_list =3D NULL; =20 + qemu_mutex_lock(&mon_fdsets_lock); QLIST_FOREACH(mon_fdset, &mon_fdsets, next) { FdsetInfoList *fdset_info =3D g_malloc0(sizeof(*fdset_info)); FdsetFdInfoList *fdsetfd_list =3D NULL; @@ -2421,6 +2430,7 @@ FdsetInfoList *qmp_query_fdsets(Error **errp) fdset_info->next =3D fdset_list; fdset_list =3D fdset_info; } + qemu_mutex_unlock(&mon_fdsets_lock); =20 return fdset_list; } @@ -2433,6 +2443,7 @@ AddfdInfo *monitor_fdset_add_fd(int fd, bool has_fdse= t_id, int64_t fdset_id, MonFdsetFd *mon_fdset_fd; AddfdInfo *fdinfo; =20 + qemu_mutex_lock(&mon_fdsets_lock); if (has_fdset_id) { QLIST_FOREACH(mon_fdset, &mon_fdsets, next) { /* Break if match found or match impossible due to ordering by= ID */ @@ -2453,6 +2464,7 @@ AddfdInfo *monitor_fdset_add_fd(int fd, bool has_fdse= t_id, int64_t fdset_id, if (fdset_id < 0) { error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "fdset-id", "a non-negative value"); + qemu_mutex_unlock(&mon_fdsets_lock); return NULL; } /* Use specified fdset ID */ @@ -2503,16 +2515,21 @@ AddfdInfo *monitor_fdset_add_fd(int fd, bool has_fd= set_id, int64_t fdset_id, fdinfo->fdset_id =3D mon_fdset->id; fdinfo->fd =3D mon_fdset_fd->fd; =20 + qemu_mutex_unlock(&mon_fdsets_lock); return fdinfo; } =20 int monitor_fdset_get_fd(int64_t fdset_id, int flags) { -#ifndef _WIN32 +#ifdef _WIN32 + return -ENOENT; +#else MonFdset *mon_fdset; MonFdsetFd *mon_fdset_fd; int mon_fd_flags; + int ret; =20 + qemu_mutex_lock(&mon_fdsets_lock); QLIST_FOREACH(mon_fdset, &mon_fdsets, next) { if (mon_fdset->id !=3D fdset_id) { continue; @@ -2520,20 +2537,24 @@ int monitor_fdset_get_fd(int64_t fdset_id, int flag= s) QLIST_FOREACH(mon_fdset_fd, &mon_fdset->fds, next) { mon_fd_flags =3D fcntl(mon_fdset_fd->fd, F_GETFL); if (mon_fd_flags =3D=3D -1) { - return -1; + ret =3D -errno; + goto out; } =20 if ((flags & O_ACCMODE) =3D=3D (mon_fd_flags & O_ACCMODE)) { - return mon_fdset_fd->fd; + ret =3D mon_fdset_fd->fd; + goto out; } } - errno =3D EACCES; - return -1; + ret =3D -EACCES; + goto out; } -#endif + ret =3D -ENOENT; =20 - errno =3D ENOENT; - return -1; +out: + qemu_mutex_unlock(&mon_fdsets_lock); + return ret; +#endif } =20 int monitor_fdset_dup_fd_add(int64_t fdset_id, int dup_fd) @@ -2541,20 +2562,25 @@ int monitor_fdset_dup_fd_add(int64_t fdset_id, int = dup_fd) MonFdset *mon_fdset; MonFdsetFd *mon_fdset_fd_dup; =20 + qemu_mutex_lock(&mon_fdsets_lock); QLIST_FOREACH(mon_fdset, &mon_fdsets, next) { if (mon_fdset->id !=3D fdset_id) { continue; } QLIST_FOREACH(mon_fdset_fd_dup, &mon_fdset->dup_fds, next) { if (mon_fdset_fd_dup->fd =3D=3D dup_fd) { - return -1; + goto err; } } mon_fdset_fd_dup =3D g_malloc0(sizeof(*mon_fdset_fd_dup)); mon_fdset_fd_dup->fd =3D dup_fd; QLIST_INSERT_HEAD(&mon_fdset->dup_fds, mon_fdset_fd_dup, next); + qemu_mutex_unlock(&mon_fdsets_lock); return 0; } + +err: + qemu_mutex_unlock(&mon_fdsets_lock); return -1; } =20 @@ -2563,6 +2589,7 @@ static int monitor_fdset_dup_fd_find_remove(int dup_f= d, bool remove) MonFdset *mon_fdset; MonFdsetFd *mon_fdset_fd_dup; =20 + qemu_mutex_lock(&mon_fdsets_lock); QLIST_FOREACH(mon_fdset, &mon_fdsets, next) { QLIST_FOREACH(mon_fdset_fd_dup, &mon_fdset->dup_fds, next) { if (mon_fdset_fd_dup->fd =3D=3D dup_fd) { @@ -2571,13 +2598,17 @@ static int monitor_fdset_dup_fd_find_remove(int dup= _fd, bool remove) if (QLIST_EMPTY(&mon_fdset->dup_fds)) { monitor_fdset_cleanup(mon_fdset); } - return -1; + goto err; } else { + qemu_mutex_unlock(&mon_fdsets_lock); return mon_fdset->id; } } } } + +err: + qemu_mutex_unlock(&mon_fdsets_lock); return -1; } =20 @@ -4511,6 +4542,7 @@ void monitor_init_globals(void) monitor_qapi_event_init(); sortcmdlist(); qemu_mutex_init(&monitor_lock); + qemu_mutex_init(&mon_fdsets_lock); monitor_iothread_init(); } =20 diff --git a/stubs/fdset.c b/stubs/fdset.c index 6020cf28c8..4f3edf2ea4 100644 --- a/stubs/fdset.c +++ b/stubs/fdset.c @@ -14,7 +14,7 @@ int monitor_fdset_dup_fd_find(int dup_fd) =20 int monitor_fdset_get_fd(int64_t fdset_id, int flags) { - return -1; + return -ENOENT; } =20 void monitor_fdset_dup_fd_remove(int dupfd) diff --git a/util/osdep.c b/util/osdep.c index a73de0e1ba..ea51d500b6 100644 --- a/util/osdep.c +++ b/util/osdep.c @@ -302,7 +302,8 @@ int qemu_open(const char *name, int flags, ...) } =20 fd =3D monitor_fdset_get_fd(fdset_id, flags); - if (fd =3D=3D -1) { + if (fd < 0) { + errno =3D -fd; return -1; } =20 --=20 2.17.0