[PATCH 5.7 054/244] gfs2: The freeze glock should never be frozen

From: Greg Kroah-Hartman
Date: Mon Jul 20 2020 - 12:07:56 EST


From: Bob Peterson <rpeterso@xxxxxxxxxx>

[ Upstream commit c860f8ffbea8924de05a281b937128773d30a77c ]

Before this patch, some gfs2 code locked the freeze glock with LM_FLAG_NOEXP
(Do not freeze) flag, and some did not. We never want to freeze the freeze
glock, so this patch makes it consistently use LM_FLAG_NOEXP always.

Signed-off-by: Bob Peterson <rpeterso@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/gfs2/ops_fstype.c | 3 ++-
fs/gfs2/super.c | 16 +++++++++-------
2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index a2c0554a18901..6d18d2c91add2 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -1140,7 +1140,8 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc)
struct gfs2_holder freeze_gh;

error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED,
- GL_EXACT, &freeze_gh);
+ LM_FLAG_NOEXP | GL_EXACT,
+ &freeze_gh);
if (error) {
fs_err(sdp, "can't make FS RO: %d\n", error);
goto fail_per_node;
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 3bc76cf382fb9..160bb4598b48b 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -167,7 +167,8 @@ int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
if (error)
return error;

- error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, GL_EXACT,
+ error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED,
+ LM_FLAG_NOEXP | GL_EXACT,
&freeze_gh);
if (error)
goto fail_threads;
@@ -429,7 +430,7 @@ static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp)
}

error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_EXCLUSIVE,
- 0, &sdp->sd_freeze_gh);
+ LM_FLAG_NOEXP, &sdp->sd_freeze_gh);
if (error)
goto out;

@@ -612,14 +613,15 @@ int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
!gfs2_glock_is_locked_by_me(sdp->sd_freeze_gl)) {
if (!log_write_allowed) {
error = gfs2_glock_nq_init(sdp->sd_freeze_gl,
- LM_ST_SHARED,
- LM_FLAG_TRY | GL_EXACT,
+ LM_ST_SHARED, LM_FLAG_TRY |
+ LM_FLAG_NOEXP | GL_EXACT,
&freeze_gh);
if (error == GLR_TRYFAILED)
error = 0;
} else {
error = gfs2_glock_nq_init(sdp->sd_freeze_gl,
- LM_ST_SHARED, GL_EXACT,
+ LM_ST_SHARED,
+ LM_FLAG_NOEXP | GL_EXACT,
&freeze_gh);
if (error && !gfs2_withdrawn(sdp))
return error;
@@ -761,8 +763,8 @@ void gfs2_freeze_func(struct work_struct *work)
struct super_block *sb = sdp->sd_vfs;

atomic_inc(&sb->s_active);
- error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, GL_EXACT,
- &freeze_gh);
+ error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED,
+ LM_FLAG_NOEXP | GL_EXACT, &freeze_gh);
if (error) {
fs_info(sdp, "GFS2: couldn't get freeze lock : %d\n", error);
gfs2_assert_withdraw(sdp, 0);
--
2.25.1