From 33eef488233850a3eeb806bf11d562c86eaacb72 Mon Sep 17 00:00:00 2001 From: Fam Zheng Date: Fri, 17 Jan 2014 03:07:51 +0100 Subject: [PATCH 08/34] nbd: use BlockDriverState refcnt RH-Author: Fam Zheng Message-id: <1389928083-8921-7-git-send-email-famz@redhat.com> Patchwork-id: 56768 O-Subject: [RHEL-7 qemu-kvm PATCH 06/18] nbd: use BlockDriverState refcnt Bugzilla: 1041301 RH-Acked-by: Jeffrey Cody RH-Acked-by: Kevin Wolf RH-Acked-by: Stefan Hajnoczi Previously, nbd calls drive_get_ref() on the drive of bs. A BDS doesn't always have associated dinfo, which nbd doesn't care either. We already have BDS ref count, so use it to make it safe for a BDS w/o blockdev. Signed-off-by: Fam Zheng Signed-off-by: Stefan Hajnoczi (cherry picked from commit 38b54b6dc18ae7e2a32e5ae38b312fb13f0584c8) Signed-off-by: Fam Zheng --- blockdev-nbd.c | 10 +--------- nbd.c | 5 +++++ 2 files changed, 6 insertions(+), 9 deletions(-) Signed-off-by: Miroslav Rezanina --- blockdev-nbd.c | 10 +--------- nbd.c | 5 +++++ 2 files changed, 6 insertions(+), 9 deletions(-) diff --git a/blockdev-nbd.c b/blockdev-nbd.c index 95f10c8..922cf56 100644 --- a/blockdev-nbd.c +++ b/blockdev-nbd.c @@ -69,12 +69,6 @@ static void nbd_close_notifier(Notifier *n, void *data) g_free(cn); } -static void nbd_server_put_ref(NBDExport *exp) -{ - BlockDriverState *bs = nbd_export_get_blockdev(exp); - drive_put_ref(drive_get_by_blockdev(bs)); -} - void qmp_nbd_server_add(const char *device, bool has_writable, bool writable, Error **errp) { @@ -105,11 +99,9 @@ void qmp_nbd_server_add(const char *device, bool has_writable, bool writable, writable = false; } - exp = nbd_export_new(bs, 0, -1, writable ? 0 : NBD_FLAG_READ_ONLY, - nbd_server_put_ref); + exp = nbd_export_new(bs, 0, -1, writable ? 0 : NBD_FLAG_READ_ONLY, NULL); nbd_export_set_name(exp, device); - drive_get_ref(drive_get_by_blockdev(bs)); n = g_malloc0(sizeof(NBDCloseNotifier)); n->n.notify = nbd_close_notifier; diff --git a/nbd.c b/nbd.c index 2606403..f258cdd 100644 --- a/nbd.c +++ b/nbd.c @@ -881,6 +881,7 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, exp->nbdflags = nbdflags; exp->size = size == -1 ? bdrv_getlength(bs) : size; exp->close = close; + bdrv_ref(bs); return exp; } @@ -927,6 +928,10 @@ void nbd_export_close(NBDExport *exp) } nbd_export_set_name(exp, NULL); nbd_export_put(exp); + if (exp->bs) { + bdrv_unref(exp->bs); + exp->bs = NULL; + } } void nbd_export_get(NBDExport *exp) -- 1.7.1