1 /**
2  * defrag.c
3  *
4  * Copyright (c) 2015 Jaegeuk Kim <jaegeuk@kernel.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #include "fsck.h"
11 
12 static int migrate_block(struct f2fs_sb_info *sbi, u64 from, u64 to)
13 {
14 	void *raw = calloc(BLOCK_SZ, 1);
15 	struct seg_entry *se;
16 	struct f2fs_summary sum;
17 	u64 offset;
18 	int ret, type;
19 
20 	ASSERT(raw != NULL);
21 
22 	/* read from */
23 	ret = dev_read_block(raw, from);
24 	ASSERT(ret >= 0);
25 
26 	/* write to */
27 	ret = dev_write_block(raw, to);
28 	ASSERT(ret >= 0);
29 
30 	/* update sit bitmap & valid_blocks && se->type */
31 	se = get_seg_entry(sbi, GET_SEGNO(sbi, from));
32 	offset = OFFSET_IN_SEG(sbi, from);
33 	type = se->type;
34 	se->valid_blocks--;
35 	f2fs_clear_bit(offset, (char *)se->cur_valid_map);
36 	se->dirty = 1;
37 
38 	se = get_seg_entry(sbi, GET_SEGNO(sbi, to));
39 	offset = OFFSET_IN_SEG(sbi, to);
40 	se->type = type;
41 	se->valid_blocks++;
42 	f2fs_set_bit(offset, (char *)se->cur_valid_map);
43 	se->dirty = 1;
44 
45 	/* read/write SSA */
46 	get_sum_entry(sbi, from, &sum);
47 	update_sum_entry(sbi, to, &sum);
48 
49 	/* if data block, read node and update node block */
50 	if (IS_DATASEG(type))
51 		update_data_blkaddr(sbi, le32_to_cpu(sum.nid),
52 				le16_to_cpu(sum.ofs_in_node), to);
53 	else
54 		update_nat_blkaddr(sbi, 0, le32_to_cpu(sum.nid), to);
55 
56 	DBG(0, "Migrate %s block %"PRIx64" -> %"PRIx64"\n",
57 					IS_DATASEG(type) ? "data" : "node",
58 					from, to);
59 	free(raw);
60 	return 0;
61 }
62 
63 int f2fs_defragment(struct f2fs_sb_info *sbi, u64 from, u64 len, u64 to, int left)
64 {
65 	struct seg_entry *se;
66 	u64 idx, offset;
67 
68 	/* flush NAT/SIT journal entries */
69 	flush_journal_entries(sbi);
70 
71 	for (idx = from; idx < from + len; idx++) {
72 		u64 target = to;
73 
74 		se = get_seg_entry(sbi, GET_SEGNO(sbi, idx));
75 		offset = OFFSET_IN_SEG(sbi, idx);
76 
77 		if (!f2fs_test_bit(offset, (const char *)se->cur_valid_map))
78 			continue;
79 
80 		if (find_next_free_block(sbi, &target, left, se->type, false)) {
81 			MSG(0, "Not enough space to migrate blocks");
82 			return -1;
83 		}
84 
85 		if (migrate_block(sbi, idx, target)) {
86 			ASSERT_MSG("Found inconsistency: please run FSCK");
87 			return -1;
88 		}
89 	}
90 
91 	/* update curseg info; can update sit->types */
92 	move_curseg_info(sbi, to, left);
93 	zero_journal_entries(sbi);
94 	write_curseg_info(sbi);
95 
96 	/* flush dirty sit entries */
97 	flush_sit_entries(sbi);
98 
99 	write_checkpoint(sbi);
100 
101 	return 0;
102 }
103