[PATCH RFC 15/17] ubifs: repair: Write master node

[Zhihao Cheng]

This is the 13/13 step of repairing. Since all meta areas are ready,
master node can be updated. After this step, a consistent UBIFS image
can be mounted, and it should pass all tests from chk_fs, chk_general,
chk_index, chk_lprops and chk_orphans.

Signed-off-by: Zhihao Cheng <chengzhihao1@xxxxxxxxxx>
---
 fs/ubifs/repair.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 77 insertions(+)

diff --git a/fs/ubifs/repair.c b/fs/ubifs/repair.c
index 42124cda5d7d..f2600bbb1431 100644
--- a/fs/ubifs/repair.c
+++ b/fs/ubifs/repair.c
@@ -2225,6 +2225,8 @@ static int traverse_files_and_nodes(struct ubifs_info *c)
 		     ubifs_get_type_name(ubifs_get_dent_type(file->ino.mode)),
 		     c->vi.ubi_num, c->vi.vol_id);
 
+		c->highest_inum = max(c->highest_inum, file->inum);
+
 		err = parse_node_info(c, &file->ino.header, &file->ino.key,
 				      NULL, 0, &idx_list, &idx_cnt);
 		if (err)
@@ -2404,6 +2406,75 @@ static int clean_log(struct ubifs_info *c)
 	return 0;
 }
 
+/**
+ * write_master - write master nodes.
+ * @c: UBIFS file-system description object
+ *
+ * This function updates meta information into master node and writes master
+ * node into master area.
+ */
+static int write_master(struct ubifs_info *c)
+{
+	int err, lnum;
+	struct ubifs_mst_node *mst;
+
+	mst = kzalloc(c->mst_node_alsz, GFP_KERNEL);
+	if (!mst)
+		return -ENOMEM;
+
+	mst->ch.node_type = UBIFS_MST_NODE;
+	mst->log_lnum     = cpu_to_le32(UBIFS_LOG_LNUM);
+	mst->highest_inum = cpu_to_le64(c->highest_inum);
+	mst->cmt_no       = 0;
+	mst->root_lnum    = cpu_to_le32(c->zroot.lnum);
+	mst->root_offs    = cpu_to_le32(c->zroot.offs);
+	mst->root_len     = cpu_to_le32(c->zroot.len);
+	mst->gc_lnum      = cpu_to_le32(c->gc_lnum);
+	mst->ihead_lnum   = cpu_to_le32(c->ihead_lnum);
+	mst->ihead_offs   = cpu_to_le32(c->ihead_offs);
+	mst->index_size   = cpu_to_le64(c->calc_idx_sz);
+	mst->lpt_lnum     = cpu_to_le32(c->lpt_lnum);
+	mst->lpt_offs     = cpu_to_le32(c->lpt_offs);
+	mst->nhead_lnum   = cpu_to_le32(c->nhead_lnum);
+	mst->nhead_offs   = cpu_to_le32(c->nhead_offs);
+	mst->ltab_lnum    = cpu_to_le32(c->ltab_lnum);
+	mst->ltab_offs    = cpu_to_le32(c->ltab_offs);
+	mst->lsave_lnum   = cpu_to_le32(c->lsave_lnum);
+	mst->lsave_offs   = cpu_to_le32(c->lsave_offs);
+	mst->lscan_lnum   = cpu_to_le32(c->main_first);
+	mst->empty_lebs   = cpu_to_le32(c->lst.empty_lebs);
+	mst->idx_lebs     = cpu_to_le32(c->lst.idx_lebs);
+	mst->leb_cnt      = cpu_to_le32(c->leb_cnt);
+	mst->total_free   = cpu_to_le64(c->lst.total_free);
+	mst->total_dirty  = cpu_to_le64(c->lst.total_dirty);
+	mst->total_used   = cpu_to_le64(c->lst.total_used);
+	mst->total_dead   = cpu_to_le64(c->lst.total_dead);
+	mst->total_dark   = cpu_to_le64(c->lst.total_dark);
+	mst->flags	  |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
+
+	lnum = UBIFS_MST_LNUM;
+	err = ubifs_leb_unmap(c, lnum);
+	if (err)
+		goto out;
+	err = ubifs_write_node_hmac(c, mst, UBIFS_MST_NODE_SZ, lnum, 0,
+				    offsetof(struct ubifs_mst_node, hmac));
+	if (err)
+		goto out;
+	lnum++;
+	err = ubifs_leb_unmap(c, lnum);
+	if (err)
+		goto out;
+	err = ubifs_write_node_hmac(c, mst, UBIFS_MST_NODE_SZ, lnum, 0,
+				    offsetof(struct ubifs_mst_node, hmac));
+	if (err)
+		goto out;
+
+out:
+	kfree(mst);
+
+	return err;
+}
+
 static int do_repair(struct ubifs_info *c)
 {
 	int err = 0;
@@ -2463,6 +2534,12 @@ static int do_repair(struct ubifs_info *c)
 		goto out;
 
 	err = ubifs_clear_orphans(c);
+	if (err)
+		goto out;
+
+	/* Step 13. Write master node. */
+	ubifs_msg(c, "Step 13: Write master");
+	err = write_master(c);
 
 out:
 	destroy_scanned_info(c, &si);
-- 
2.31.1