gfs2: Add common helper for holding and releasing the freeze glock

Many places in the gfs2 code queued and dequeued the freeze glock.
Almost all of them acquire it in SHARED mode, and need to specify the
same LM_FLAG_NOEXP and GL_EXACT flags.

This patch adds common helper functions gfs2_freeze_lock and gfs2_freeze_unlock
to make the code more readable, and to prepare for the next patch.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

1 files changed, 14 insertions, 28 deletions

diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 2f56acc41c04..ea312a94ce69 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -173,9 +173,7 @@ 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,
-				   LM_FLAG_NOEXP | GL_EXACT,
-				   &freeze_gh);
+	error = gfs2_freeze_lock(sdp, &freeze_gh, 0);
 	if (error)
 		goto fail_threads;
 
@@ -205,12 +203,12 @@ int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 
 	set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 
-	gfs2_glock_dq_uninit(&freeze_gh);
+	gfs2_freeze_unlock(&freeze_gh);
 
 	return 0;
 
 fail:
-	gfs2_glock_dq_uninit(&freeze_gh);
+	gfs2_freeze_unlock(&freeze_gh);
 fail_threads:
 	if (sdp->sd_quotad_process)
 		kthread_stop(sdp->sd_quotad_process);
@@ -452,7 +450,7 @@ static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp)
 	}
 
 	if (error)
-		gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
+		gfs2_freeze_unlock(&sdp->sd_freeze_gh);
 
 out:
 	while (!list_empty(&list)) {
@@ -616,21 +614,12 @@ int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 	gfs2_holder_mark_uninitialized(&freeze_gh);
 	if (sdp->sd_freeze_gl &&
 	    !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 |
-						   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,
-						   LM_FLAG_NOEXP | GL_EXACT,
-						   &freeze_gh);
-			if (error && !gfs2_withdrawn(sdp))
-				return error;
-		}
+		error = gfs2_freeze_lock(sdp, &freeze_gh,
+					 log_write_allowed ? 0 : LM_FLAG_TRY);
+		if (error == GLR_TRYFAILED)
+			error = 0;
+		if (error && !gfs2_withdrawn(sdp))
+			return error;
 	}
 
 	gfs2_flush_delete_work(sdp);
@@ -661,8 +650,7 @@ int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 				   atomic_read(&sdp->sd_reserving_log) == 0,
 				   HZ * 5);
 	}
-	if (gfs2_holder_initialized(&freeze_gh))
-		gfs2_glock_dq_uninit(&freeze_gh);
+	gfs2_freeze_unlock(&freeze_gh);
 
 	gfs2_quota_cleanup(sdp);
 
@@ -772,10 +760,8 @@ 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,
-				   LM_FLAG_NOEXP | GL_EXACT, &freeze_gh);
+	error = gfs2_freeze_lock(sdp, &freeze_gh, 0);
 	if (error) {
-		fs_info(sdp, "GFS2: couldn't get freeze lock : %d\n", error);
 		gfs2_assert_withdraw(sdp, 0);
 	} else {
 		atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
@@ -785,7 +771,7 @@ void gfs2_freeze_func(struct work_struct *work)
 				error);
 			gfs2_assert_withdraw(sdp, 0);
 		}
-		gfs2_glock_dq_uninit(&freeze_gh);
+		gfs2_freeze_unlock(&freeze_gh);
 	}
 	deactivate_super(sb);
 	clear_bit_unlock(SDF_FS_FROZEN, &sdp->sd_flags);
@@ -853,7 +839,7 @@ static int gfs2_unfreeze(struct super_block *sb)
                 return 0;
 	}
 
-	gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
+	gfs2_freeze_unlock(&sdp->sd_freeze_gh);
 	mutex_unlock(&sdp->sd_freeze_mutex);
 	return wait_on_bit(&sdp->sd_flags, SDF_FS_FROZEN, TASK_INTERRUPTIBLE);
 }