From b780cc615ba4795a7ef0e93b19424828a5ad456a Mon Sep 17 00:00:00 2001 From: Bob Peterson Date: Thu, 25 Jun 2020 13:30:18 -0500 Subject: [PATCH] gfs2: read-only mounts should grab the sd_freeze_gl glock Before this patch, only read-write mounts would grab the freeze glock in read-only mode, as part of gfs2_make_fs_rw. So the freeze glock was never initialized. That meant requests to freeze, which request the glock in EX, were granted without any state transition. That meant you could mount a gfs2 file system, which is currently frozen on a different cluster node, in read-only mode. This patch makes read-only mounts lock the freeze glock in SH mode, which will block for file systems that are frozen on another node. Signed-off-by: Bob Peterson --- fs/gfs2/ops_fstype.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index 094f5fe7..a2c0554 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -1136,7 +1136,17 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc) goto fail_per_node; } - if (!sb_rdonly(sb)) { + if (sb_rdonly(sb)) { + struct gfs2_holder freeze_gh; + + error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, + GL_EXACT, &freeze_gh); + if (error) { + fs_err(sdp, "can't make FS RO: %d\n", error); + goto fail_per_node; + } + gfs2_glock_dq_uninit(&freeze_gh); + } else { error = gfs2_make_fs_rw(sdp); if (error) { fs_err(sdp, "can't make FS RW: %d\n", error); -- 2.7.4