From nobody Tue May 21 13:36:40 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org ARC-Seal: i=1; a=rsa-sha256; t=1607432596; cv=none; d=zohomail.com; s=zohoarc; b=bnQJaqWgwe9nwRwXrGtlPTQWftLd+BS/qsepnTjgMZIxkZ20kWDev2jKAgYIJ4MddONWInN4kGObnpUCeAB44vRZN0gwZ27ePx5ZWJAtAs3FUWYptAeau87KUSBFUx61Xn38U4Paxj6h/GMDS0B2CrRus15YRprU3HBB9QpYj9k= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1607432596; h=Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:Message-ID:Sender:Subject:To; bh=KqJC29+YUdSyqlCknlqea4A4DRzPWvH5hAjZ9mwdKDM=; b=OM/Vu2TLyaV8gBtt/OMzUeiEpV7x7VjA3qcCX7tC+Oi7/gehKD/eedFdEDUQRg59ppSSNbp6KIfUvfk0Arozew5xtcs+MZnByyiZU+nNQb+G/P0Dg8S+V6m2ISSZdhD7vN0HHrnUgPz+1IdvJotT1nk57laPqE4YF9U+DwDdFXI= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1607432595388917.1029268313063; Tue, 8 Dec 2020 05:03:15 -0800 (PST) Received: from localhost ([::1]:55574 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kmce8-0004Tw-1N for importer@patchew.org; Tue, 08 Dec 2020 08:03:12 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:34370) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kmcac-0002tP-Du for qemu-devel@nongnu.org; Tue, 08 Dec 2020 07:59:39 -0500 Received: from mail-pf1-x442.google.com ([2607:f8b0:4864:20::442]:41970) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kmcaX-0001ZG-Ci for qemu-devel@nongnu.org; Tue, 08 Dec 2020 07:59:31 -0500 Received: by mail-pf1-x442.google.com with SMTP id t8so13832359pfg.8 for ; Tue, 08 Dec 2020 04:59:27 -0800 (PST) Received: from 64-217.abest.vip ([129.227.156.201]) by smtp.gmail.com with ESMTPSA id d22sm2985412pjw.11.2020.12.08.04.59.24 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 08 Dec 2020 04:59:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=smartx-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id; bh=KqJC29+YUdSyqlCknlqea4A4DRzPWvH5hAjZ9mwdKDM=; b=QjnhRkKnWG26oAMXinUkDpr8Sm5XNQNnm6OzxvYXlkjUg94zDGjcVpaTEvl8CqWEEX 5ck8WpuqZkQrOKqXksJyMgVkKq2N9T4OyCJRoJ1GZt2qgANQxOCSx41uf8vcEmiDWOPH 9x2KFbNLqnZ4N61su/ik4z5yorjQEQ2kg4CFfGSd8nr03FIfQAQmZtT7I1KVRdCyusRy KsZ2X9GAG8Gcu6cZRJGRczbQjtWjouOxzBBDHYxhPdFPpRgOySc1jVD3p2tlpqy3AbaZ 5fPoqu3NrBOxNT+MmEdcm7NIu2NCePNoJeQYLxjcEXD9NjuuLsowf7WRdsYGnfTB4ayw Llpw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=KqJC29+YUdSyqlCknlqea4A4DRzPWvH5hAjZ9mwdKDM=; b=MYgA8ie/Vh6vivjAcFDIAya7JvJLY8CBOJ/iv1S4mBLNMxjmzIyZMcmsmTpO3HKOEy LU7hdAQsVF87P07G/QYf27ZURoGqUO3KHlU3Xyv1qXCvIQLwXxd5V2pZSpfdHFg6tSDF fKPpwDSFXu3UxV9LInWytbGwRQbixHretiZ24SjqNw/CZftU43Swki2pp1tt/NZqMWNn /SLW7/EHLxmwtmxx3DIam7jd//iGQLhkRKWme2qlfnXiRAU5K5gaZYNbiy0Z8587J+Xz jyz4o4EK5iekLyddY1uCMSC7wDEdr5uyl9iwuSTCsBCX2iTZ0UtwuxOj5xgbTVVs3o4R YDow== X-Gm-Message-State: AOAM531ae7YIpJE6+8bxvFSzUkJ7pORZoC2Pi4vwSqHI7NjHfQaa6AmQ eAwD1N5HABJFe7f24B0NyHKvOg== X-Google-Smtp-Source: ABdhPJw/XYHdUizP/HdqthgwuaIWJsKuAwz7pQqmiYN5MJS1YbC3iytVLlnfvumzJ21V5FgKzD8A2Q== X-Received: by 2002:a17:90a:578f:: with SMTP id g15mr4262183pji.3.1607432366609; Tue, 08 Dec 2020 04:59:26 -0800 (PST) From: Li Feng To: Kevin Wolf , Max Reitz , qemu-block@nongnu.org (open list:raw), qemu-devel@nongnu.org (open list:All patches CC here) Subject: [PATCH] file-posix: detect the lock using the real file Date: Tue, 8 Dec 2020 20:59:37 +0800 Message-Id: <1607432377-87084-1-git-send-email-fengli@smartx.com> X-Mailer: git-send-email 1.8.3.1 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: none client-ip=2607:f8b0:4864:20::442; envelope-from=fengli@smartx.com; helo=mail-pf1-x442.google.com X-Spam_score_int: 14 X-Spam_score: 1.4 X-Spam_bar: + X-Spam_report: (1.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: lifeng1519@gmail.com, Li Feng , kyle@smartx.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" This patch addresses this issue: When accessing a volume on an NFS filesystem without supporting the file lo= ck, tools, like qemu-img, will complain "Failed to lock byte 100". In the original code, the qemu_has_ofd_lock will test the lock on the "/dev/null" pseudo-file. Actually, the file.locking is per-drive property, which depends on the underlay filesystem. In this patch, make the 'qemu_has_ofd_lock' with a filename be more generic and reasonable. Signed-off-by: Li Feng --- block/file-posix.c | 32 +++++++++++++++------------- include/qemu/osdep.h | 2 +- tests/test-image-locking.c | 2 +- util/osdep.c | 43 ++++++++++++++++++++++++-------------- 4 files changed, 47 insertions(+), 32 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index 806764f7e3..03be1b188c 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -595,7 +595,7 @@ static int raw_open_common(BlockDriverState *bs, QDict = *options, switch (locking) { case ON_OFF_AUTO_ON: s->use_lock =3D true; - if (!qemu_has_ofd_lock()) { + if (!qemu_has_ofd_lock(filename)) { warn_report("File lock requested but OFD locking syscall is " "unavailable, falling back to POSIX file locks"); error_printf("Due to the implementation, locks can be lost " @@ -606,7 +606,7 @@ static int raw_open_common(BlockDriverState *bs, QDict = *options, s->use_lock =3D false; break; case ON_OFF_AUTO_AUTO: - s->use_lock =3D qemu_has_ofd_lock(); + s->use_lock =3D qemu_has_ofd_lock(filename); break; default: abort(); @@ -2388,6 +2388,7 @@ raw_co_create(BlockdevCreateOptions *options, Error *= *errp) int fd; uint64_t perm, shared; int result =3D 0; + bool use_lock; =20 /* Validate options and set default values */ assert(options->driver =3D=3D BLOCKDEV_DRIVER_FILE); @@ -2428,19 +2429,22 @@ raw_co_create(BlockdevCreateOptions *options, Error= **errp) perm =3D BLK_PERM_WRITE | BLK_PERM_RESIZE; shared =3D BLK_PERM_ALL & ~BLK_PERM_RESIZE; =20 - /* Step one: Take locks */ - result =3D raw_apply_lock_bytes(NULL, fd, perm, ~shared, false, errp); - if (result < 0) { - goto out_close; - } + use_lock =3D qemu_has_ofd_lock(file_opts->filename); + if (use_lock) { + /* Step one: Take locks */ + result =3D raw_apply_lock_bytes(NULL, fd, perm, ~shared, false, er= rp); + if (result < 0) { + goto out_close; + } =20 - /* Step two: Check that nobody else has taken conflicting locks */ - result =3D raw_check_lock_bytes(fd, perm, shared, errp); - if (result < 0) { - error_append_hint(errp, - "Is another process using the image [%s]?\n", - file_opts->filename); - goto out_unlock; + /* Step two: Check that nobody else has taken conflicting locks */ + result =3D raw_check_lock_bytes(fd, perm, shared, errp); + if (result < 0) { + error_append_hint(errp, + "Is another process using the image [%s]?\n", + file_opts->filename); + goto out_unlock; + } } =20 /* Clear the file by truncating it to 0 */ diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h index f9ec8c84e9..349adad465 100644 --- a/include/qemu/osdep.h +++ b/include/qemu/osdep.h @@ -512,7 +512,7 @@ int qemu_dup(int fd); int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive); int qemu_unlock_fd(int fd, int64_t start, int64_t len); int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive); -bool qemu_has_ofd_lock(void); +bool qemu_has_ofd_lock(const char *filename); #endif =20 #if defined(__HAIKU__) && defined(__i386__) diff --git a/tests/test-image-locking.c b/tests/test-image-locking.c index ba057bd66c..3e80246081 100644 --- a/tests/test-image-locking.c +++ b/tests/test-image-locking.c @@ -149,7 +149,7 @@ int main(int argc, char **argv) =20 g_test_init(&argc, &argv, NULL); =20 - if (qemu_has_ofd_lock()) { + if (qemu_has_ofd_lock(NULL)) { g_test_add_func("/image-locking/basic", test_image_locking_basic); g_test_add_func("/image-locking/set-perm-abort", test_set_perm_abo= rt); } diff --git a/util/osdep.c b/util/osdep.c index 66d01b9160..e7e502edd1 100644 --- a/util/osdep.c +++ b/util/osdep.c @@ -42,6 +42,7 @@ extern int madvise(char *, size_t, int); static bool fips_enabled =3D false; =20 static const char *hw_version =3D QEMU_HW_VERSION; +static const char *null_device =3D "/dev/null"; =20 int socket_set_cork(int fd, int v) { @@ -187,11 +188,10 @@ static int qemu_parse_fdset(const char *param) return qemu_parse_fd(param); } =20 -static void qemu_probe_lock_ops(void) +static void qemu_probe_lock_ops_fd(int fd) { if (fcntl_op_setlk =3D=3D -1) { #ifdef F_OFD_SETLK - int fd; int ret; struct flock fl =3D { .l_whence =3D SEEK_SET, @@ -200,17 +200,7 @@ static void qemu_probe_lock_ops(void) .l_type =3D F_WRLCK, }; =20 - fd =3D open("/dev/null", O_RDWR); - if (fd < 0) { - fprintf(stderr, - "Failed to open /dev/null for OFD lock probing: %s\n", - strerror(errno)); - fcntl_op_setlk =3D F_SETLK; - fcntl_op_getlk =3D F_GETLK; - return; - } ret =3D fcntl(fd, F_OFD_GETLK, &fl); - close(fd); if (!ret) { fcntl_op_setlk =3D F_OFD_SETLK; fcntl_op_getlk =3D F_OFD_GETLK; @@ -225,9 +215,30 @@ static void qemu_probe_lock_ops(void) } } =20 -bool qemu_has_ofd_lock(void) +static void qemu_probe_lock_ops(const char *filename) +{ + int fd; + if (filename) { + fd =3D open(filename, O_RDWR); + } else { + fd =3D open(null_device, O_RDONLY); + } + if (fd < 0) { + fprintf(stderr, + "Failed to open %s for OFD lock probing: %s\n", + filename ? filename : null_device, + strerror(errno)); + fcntl_op_setlk =3D F_SETLK; + fcntl_op_getlk =3D F_GETLK; + return; + } + qemu_probe_lock_ops_fd(fd); + close(fd); +} + +bool qemu_has_ofd_lock(const char *filename) { - qemu_probe_lock_ops(); + qemu_probe_lock_ops(filename); #ifdef F_OFD_SETLK return fcntl_op_setlk =3D=3D F_OFD_SETLK; #else @@ -244,7 +255,7 @@ static int qemu_lock_fcntl(int fd, int64_t start, int64= _t len, int fl_type) .l_len =3D len, .l_type =3D fl_type, }; - qemu_probe_lock_ops(); + qemu_probe_lock_ops_fd(fd); do { ret =3D fcntl(fd, fcntl_op_setlk, &fl); } while (ret =3D=3D -1 && errno =3D=3D EINTR); @@ -270,7 +281,7 @@ int qemu_lock_fd_test(int fd, int64_t start, int64_t le= n, bool exclusive) .l_len =3D len, .l_type =3D exclusive ? F_WRLCK : F_RDLCK, }; - qemu_probe_lock_ops(); + qemu_probe_lock_ops_fd(fd); ret =3D fcntl(fd, fcntl_op_getlk, &fl); if (ret =3D=3D -1) { return -errno; --=20 2.24.3