fsck.ubifs: Move common functions and data structures into check_space.c

This is a preparation for adding LPT checking support. Move some data
structures and functions into check_space.c, also factor out some common
functions in libubifs:
 1. Move 'lpts' from rebuild module, make it resuable for non-rebuild_fs
    modes.
 2. Move function 'get_free_leb' from rebuild_fs.c, it could be reused in
    building LPT.
 3. Move function 'build_lpt' from rebuild_fs.c, it could be reused in
    building LPT.
 4. Factor out lpt nodes freeing into a new function ubifs_free_lpt_nodes.
 5. Factor out nnode dirty marking implementations into a new function
    ubifs_make_nnode_dirty.
 5. Export the function of nnode number calculation, calc_nnode_num is
    renamed as ubifs_calc_nnode_num.
 6. Export the function of making pnode dirty, do_make_pnode_dirty is
    renamed as ubifs_make_pnode_dirty.
 7. Rename next_pnode_to_dirty to ubifs_find_next_pnode and export it.
 8. Export free_buds and expend its parameters.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 94 insertions, 0 deletions

diff --git a/ubifs-utils/fsck.ubifs/check_space.c b/ubifs-utils/fsck.ubifs/check_space.c
new file mode 100644
index 0000000..f758bf1
--- /dev/null
+++ b/ubifs-utils/fsck.ubifs/check_space.c
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2024, Huawei Technologies Co, Ltd.
+ *
+ * Authors: Zhihao Cheng <chengzhihao1@huawei.com>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "linux_err.h"
+#include "bitops.h"
+#include "kmem.h"
+#include "ubifs.h"
+#include "defs.h"
+#include "debug.h"
+#include "key.h"
+#include "misc.h"
+#include "fsck.ubifs.h"
+
+/**
+ * get_free_leb - get a free LEB according to @FSCK(c)->used_lebs.
+ * @c: UBIFS file-system description object
+ *
+ * This function tries to find a free LEB, lnum is returned if found, otherwise
+ * %-ENOSPC is returned.
+ */
+int get_free_leb(struct ubifs_info *c)
+{
+	int lnum;
+
+	lnum = find_next_zero_bit(FSCK(c)->used_lebs, c->main_lebs, 0);
+	if (lnum >= c->main_lebs) {
+		ubifs_err(c, "No space left.");
+		return -ENOSPC;
+	}
+	set_bit(lnum, FSCK(c)->used_lebs);
+	lnum += c->main_first;
+
+	return lnum;
+}
+
+/**
+ * build_lpt - construct LPT and write it into flash.
+ * @c: UBIFS file-system description object
+ * @calculate_lp_cb: callback function to calculate the properties for given LEB
+ *
+ * This function builds LPT according to the calculated results by
+ * @calculate_lp_cb and writes LPT into flash. Returns zero in case of success,
+ * a negative error code in case of failure.
+ */
+int build_lpt(struct ubifs_info *c, calculate_lp_callback calculate_lp_cb)
+{
+	int i, err, lnum, free, dirty;
+	u8 hash_lpt[UBIFS_HASH_ARR_SZ];
+
+	memset(&c->lst, 0, sizeof(struct ubifs_lp_stats));
+	/* Set gc lnum. */
+	lnum = get_free_leb(c);
+	if (lnum < 0)
+		return lnum;
+	c->gc_lnum = lnum;
+
+	/* Update LPT. */
+	for (i = 0; i < c->main_lebs; i++) {
+		err = calculate_lp_cb(c, i, &free, &dirty);
+		if (err)
+			return err;
+
+		FSCK(c)->lpts[i].free = free;
+		FSCK(c)->lpts[i].dirty = dirty;
+		c->lst.total_free += free;
+		c->lst.total_dirty += dirty;
+
+		if (free == c->leb_size)
+			c->lst.empty_lebs++;
+
+		if (FSCK(c)->lpts[i].flags & LPROPS_INDEX) {
+			c->lst.idx_lebs += 1;
+		} else {
+			int spc;
+
+			spc = free + dirty;
+			if (spc < c->dead_wm)
+				c->lst.total_dead += spc;
+			else
+				c->lst.total_dark += ubifs_calc_dark(c, spc);
+			c->lst.total_used += c->leb_size - spc;
+		}
+	}
+
+	/* Write LPT. */
+	return ubifs_create_lpt(c, FSCK(c)->lpts, c->main_lebs, hash_lpt);
+}