From owner-svn-src-head@freebsd.org Sun Nov 13 03:56:28 2016 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 43C77C2E760; Sun, 13 Nov 2016 03:56:28 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id D69B4B5; Sun, 13 Nov 2016 03:56:27 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id uAD3uRb3083256; Sun, 13 Nov 2016 03:56:27 GMT (envelope-from mav@FreeBSD.org) Received: (from mav@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id uAD3uQl5083254; Sun, 13 Nov 2016 03:56:26 GMT (envelope-from mav@FreeBSD.org) Message-Id: <201611130356.uAD3uQl5083254@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mav set sender to mav@FreeBSD.org using -f From: Alexander Motin Date: Sun, 13 Nov 2016 03:56:26 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r308608 - head/sys/geom/mirror X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 13 Nov 2016 03:56:30 -0000 Author: mav Date: Sun Nov 13 03:56:26 2016 New Revision: 308608 URL: https://svnweb.freebsd.org/changeset/base/308608 Log: Use providergone method to cover race between destroy and g_access(). Reviewed by: markj MFC after: 2 weeks Sponsored by: iXsystems, Inc. Modified: head/sys/geom/mirror/g_mirror.c head/sys/geom/mirror/g_mirror.h Modified: head/sys/geom/mirror/g_mirror.c ============================================================================== --- head/sys/geom/mirror/g_mirror.c Sun Nov 13 00:46:11 2016 (r308607) +++ head/sys/geom/mirror/g_mirror.c Sun Nov 13 03:56:26 2016 (r308608) @@ -79,12 +79,12 @@ SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, static eventhandler_tag g_mirror_post_sync = NULL; static int g_mirror_shutdown = 0; -static int g_mirror_destroy_geom(struct gctl_req *req, struct g_class *mp, - struct g_geom *gp); +static g_ctl_destroy_geom_t g_mirror_destroy_geom; static g_taste_t g_mirror_taste; +static g_init_t g_mirror_init; +static g_fini_t g_mirror_fini; +static g_provgone_t g_mirror_providergone; static g_resize_t g_mirror_resize; -static void g_mirror_init(struct g_class *mp); -static void g_mirror_fini(struct g_class *mp); struct g_class g_mirror_class = { .name = G_MIRROR_CLASS_NAME, @@ -94,6 +94,7 @@ struct g_class g_mirror_class = { .destroy_geom = g_mirror_destroy_geom, .init = g_mirror_init, .fini = g_mirror_fini, + .providergone = g_mirror_providergone, .resize = g_mirror_resize }; @@ -508,6 +509,26 @@ g_mirror_destroy_disk(struct g_mirror_di } static void +g_mirror_free_device(struct g_mirror_softc *sc) +{ + + mtx_destroy(&sc->sc_queue_mtx); + mtx_destroy(&sc->sc_events_mtx); + mtx_destroy(&sc->sc_done_mtx); + sx_destroy(&sc->sc_lock); + free(sc, M_MIRROR); +} + +static void +g_mirror_providergone(struct g_provider *pp) +{ + struct g_mirror_softc *sc = pp->private; + + if ((--sc->sc_refcnt) == 0) + g_mirror_free_device(sc); +} + +static void g_mirror_destroy_device(struct g_mirror_softc *sc) { struct g_mirror_disk *disk; @@ -549,12 +570,10 @@ g_mirror_destroy_device(struct g_mirror_ g_wither_geom(sc->sc_sync.ds_geom, ENXIO); G_MIRROR_DEBUG(0, "Device %s destroyed.", gp->name); g_wither_geom(gp, ENXIO); - g_topology_unlock(); - mtx_destroy(&sc->sc_queue_mtx); - mtx_destroy(&sc->sc_events_mtx); - mtx_destroy(&sc->sc_done_mtx); sx_xunlock(&sc->sc_lock); - sx_destroy(&sc->sc_lock); + if ((--sc->sc_refcnt) == 0) + g_mirror_free_device(sc); + g_topology_unlock(); } static void @@ -868,7 +887,7 @@ g_mirror_flush_done(struct bio *bp) struct bio *pbp; pbp = bp->bio_parent; - sc = pbp->bio_to->geom->softc; + sc = pbp->bio_to->private; mtx_lock(&sc->sc_done_mtx); if (pbp->bio_error == 0) pbp->bio_error = bp->bio_error; @@ -905,7 +924,7 @@ g_mirror_regular_request(struct bio *bp) g_topology_assert_not(); pbp = bp->bio_parent; - sc = pbp->bio_to->geom->softc; + sc = pbp->bio_to->private; bp->bio_from->index--; if (bp->bio_cmd == BIO_WRITE) sc->sc_writes--; @@ -1036,7 +1055,7 @@ g_mirror_candelete(struct bio *bp) struct g_mirror_disk *disk; int *val; - sc = bp->bio_to->geom->softc; + sc = bp->bio_to->private; LIST_FOREACH(disk, &sc->sc_disks, d_next) { if (disk->d_flags & G_MIRROR_DISK_FLAG_CANDELETE) break; @@ -1061,7 +1080,7 @@ g_mirror_kernel_dump(struct bio *bp) * we will not be able to read the dump after the reboot if it will be * connected and synchronized later. Can we do something better? */ - sc = bp->bio_to->geom->softc; + sc = bp->bio_to->private; disk = LIST_FIRST(&sc->sc_disks); gkd = (struct g_kerneldump *)bp->bio_data; @@ -1121,7 +1140,7 @@ g_mirror_start(struct bio *bp) { struct g_mirror_softc *sc; - sc = bp->bio_to->geom->softc; + sc = bp->bio_to->private; /* * If sc == NULL or there are no valid disks, provider's error * should be set and g_mirror_start() should not be called at all. @@ -1637,7 +1656,7 @@ g_mirror_register_request(struct bio *bp { struct g_mirror_softc *sc; - sc = bp->bio_to->geom->softc; + sc = bp->bio_to->private; switch (bp->bio_cmd) { case BIO_READ: switch (sc->sc_balance) { @@ -1804,7 +1823,6 @@ g_mirror_try_destroy(struct g_mirror_sof } else { g_topology_unlock(); g_mirror_destroy_device(sc); - free(sc, M_MIRROR); } return (1); } @@ -2117,6 +2135,8 @@ g_mirror_launch_provider(struct g_mirror } } } + pp->private = sc; + sc->sc_refcnt++; sc->sc_provider = pp; g_error_provider(pp, 0); g_topology_unlock(); @@ -2898,9 +2918,7 @@ g_mirror_access(struct g_provider *pp, i G_MIRROR_DEBUG(2, "Access request for %s: r%dw%de%d.", pp->name, acr, acw, ace); - sc = pp->geom->softc; - if (sc == NULL && acr <= 0 && acw <= 0 && ace <= 0) - return (0); + sc = pp->private; KASSERT(sc != NULL, ("NULL softc (provider=%s).", pp->name)); g_topology_unlock(); @@ -2959,6 +2977,7 @@ g_mirror_create(struct g_class *mp, cons sc->sc_idle = 1; sc->sc_last_write = time_uptime; sc->sc_writes = 0; + sc->sc_refcnt = 1; sx_init(&sc->sc_lock, "gmirror:lock"); bioq_init(&sc->sc_queue); mtx_init(&sc->sc_queue_mtx, "gmirror:queue", NULL, MTX_DEF); @@ -2989,12 +3008,8 @@ g_mirror_create(struct g_class *mp, cons G_MIRROR_DEBUG(1, "Cannot create kernel thread for %s.", sc->sc_name); g_destroy_geom(sc->sc_sync.ds_geom); - mtx_destroy(&sc->sc_done_mtx); - mtx_destroy(&sc->sc_events_mtx); - mtx_destroy(&sc->sc_queue_mtx); - sx_destroy(&sc->sc_lock); g_destroy_geom(sc->sc_geom); - free(sc, M_MIRROR); + g_mirror_free_device(sc); return (NULL); } @@ -3017,8 +3032,6 @@ g_mirror_destroy(struct g_mirror_softc * struct g_mirror_disk *disk; g_topology_assert_not(); - if (sc == NULL) - return (ENXIO); sx_assert(&sc->sc_lock, SX_XLOCKED); if (sc->sc_provider_open != 0 || SCHEDULER_STOPPED()) { @@ -3068,7 +3081,6 @@ g_mirror_destroy(struct g_mirror_softc * G_MIRROR_DEBUG(4, "%s: Woken up %p.", __func__, &sc->sc_worker); sx_xlock(&sc->sc_lock); g_mirror_destroy_device(sc); - free(sc, M_MIRROR); return (0); } Modified: head/sys/geom/mirror/g_mirror.h ============================================================================== --- head/sys/geom/mirror/g_mirror.h Sun Nov 13 00:46:11 2016 (r308607) +++ head/sys/geom/mirror/g_mirror.h Sun Nov 13 03:56:26 2016 (r308608) @@ -207,6 +207,7 @@ struct g_mirror_softc { int sc_idle; /* DIRTY flags removed. */ time_t sc_last_write; u_int sc_writes; + u_int sc_refcnt; /* Number of softc references */ TAILQ_HEAD(, g_mirror_event) sc_events; struct mtx sc_events_mtx;