[Cluster-devel] [PATCH v2 3/3] gfs2: Recover statfs info in journal head

[Abhi Das <adas@redhat.com>]

Apply the outstanding statfs changes in the journal head to the
master statfs file. Zero out the local statfs file for good measure.

Signed-off-by: Abhi Das <adas@redhat.com>
---
 fs/gfs2/lops.c     |  2 +-
 fs/gfs2/lops.h     |  1 +
 fs/gfs2/recovery.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 73 insertions(+), 1 deletion(-)

diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index ed1da4323967..ed69298dd824 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -823,7 +823,7 @@ static int buf_lo_scan_elements(struct gfs2_jdesc *jd, u32 start,
  *
  */
 
-static void gfs2_meta_sync(struct gfs2_glock *gl)
+void gfs2_meta_sync(struct gfs2_glock *gl)
 {
 	struct address_space *mapping = gfs2_glock2aspace(gl);
 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
diff --git a/fs/gfs2/lops.h b/fs/gfs2/lops.h
index 9c5e4e491e03..4a3d8aecdf82 100644
--- a/fs/gfs2/lops.h
+++ b/fs/gfs2/lops.h
@@ -27,6 +27,7 @@ extern void gfs2_log_submit_bio(struct bio **biop, int opf);
 extern void gfs2_pin(struct gfs2_sbd *sdp, struct buffer_head *bh);
 extern int gfs2_find_jhead(struct gfs2_jdesc *jd,
 			   struct gfs2_log_header_host *head, bool keep_cache);
+extern void gfs2_meta_sync(struct gfs2_glock *gl);
 
 static inline unsigned int buf_limit(struct gfs2_sbd *sdp)
 {
diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c
index a8bb17e355b8..21661c5e497e 100644
--- a/fs/gfs2/recovery.c
+++ b/fs/gfs2/recovery.c
@@ -296,6 +296,76 @@ static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
 		sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message);
 }
 
+static int update_statfs_inode(struct gfs2_jdesc *jd,
+			       struct gfs2_log_header_host *head,
+			       struct inode *inode)
+{
+	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
+	struct gfs2_inode *ip;
+	struct buffer_head *bh;
+	struct gfs2_statfs_change_host sc;
+	int error = 0;
+
+	BUG_ON(!inode);
+	ip = GFS2_I(inode);
+
+	error = gfs2_meta_inode_buffer(ip, &bh);
+	if (error)
+		goto out;
+
+	spin_lock(&sdp->sd_statfs_spin);
+
+	if (head) { /* Updating the master statfs inode */
+		gfs2_statfs_change_in(&sc, bh->b_data + sizeof(struct gfs2_dinode));
+		sc.sc_total += head->lh_local_total;
+		sc.sc_free += head->lh_local_free;
+		sc.sc_dinodes += head->lh_local_dinodes;
+		gfs2_statfs_change_out(&sc, bh->b_data + sizeof(struct gfs2_dinode));
+
+		fs_info(sdp, "jid=%u: Updated master statfs Total:%lld, "
+			"Free:%lld, Dinodes:%lld after change "
+			"[%+lld,%+lld,%+lld]\n", jd->jd_jid, sc.sc_total,
+			sc.sc_free, sc.sc_dinodes, head->lh_local_total,
+			head->lh_local_free, head->lh_local_dinodes);
+	} else { /* Zeroing out one of the local statfs inodes */
+		memset(bh->b_data + sizeof(struct gfs2_dinode), 0,
+		       sizeof(struct gfs2_statfs_change));
+		if (jd->jd_jid == sdp->sd_lockstruct.ls_jid) {
+			memset(&sdp->sd_statfs_local, 0,
+			       sizeof(struct gfs2_statfs_change_host));
+		}
+	}
+	spin_unlock(&sdp->sd_statfs_spin);
+
+	mark_buffer_dirty(bh);
+	brelse(bh);
+	gfs2_meta_sync(ip->i_gl);
+
+out:
+	return error;
+}
+
+static void recover_local_statfs(struct gfs2_jdesc *jd,
+				 struct gfs2_log_header_host *head)
+{
+	int error;
+	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
+
+	if (!head->lh_local_total && !head->lh_local_free
+	    && !head->lh_local_dinodes) /* No change */
+		goto zero_local;
+
+	error = update_statfs_inode(jd, head, sdp->sd_statfs_inode);
+	if (error)
+		goto out;
+
+zero_local:
+	error = update_statfs_inode(jd, NULL,
+				    find_lcl_statfs_inode(sdp, jd->jd_jid));
+out:
+	return;
+}
+
 void gfs2_recover_func(struct work_struct *work)
 {
 	struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
@@ -415,6 +485,7 @@ void gfs2_recover_func(struct work_struct *work)
 				goto fail_gunlock_thaw;
 		}
 
+		recover_local_statfs(jd, &head);
 		clean_journal(jd, &head);
 		up_read(&sdp->sd_log_flush_lock);
 
-- 
2.20.1