1 /**
2  * node.c
3  *
4  * Many parts of codes are copied from Linux kernel/fs/f2fs.
5  *
6  * Copyright (C) 2015 Huawei Ltd.
7  * Witten by:
8  *   Hou Pengyang <houpengyang@huawei.com>
9  *   Liu Shuoran <liushuoran@huawei.com>
10  *   Jaegeuk Kim <jaegeuk@kernel.org>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License version 2 as
14  * published by the Free Software Foundation.
15  */
16 #include "fsck.h"
17 #include "node.h"
18 
19 void f2fs_alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid)
20 {
21 	struct f2fs_nm_info *nm_i = NM_I(sbi);
22 	nid_t i;
23 
24 	for (i = 0; i < nm_i->max_nid; i++)
25 		if(f2fs_test_bit(i, nm_i->nid_bitmap) == 0)
26 			break;
27 
28 	ASSERT(i < nm_i->max_nid);
29 	f2fs_set_bit(i, nm_i->nid_bitmap);
30 	*nid = i;
31 }
32 
33 void f2fs_release_nid(struct f2fs_sb_info *sbi, nid_t nid)
34 {
35 	struct f2fs_nm_info *nm_i = NM_I(sbi);
36 
37 	ASSERT(nid < nm_i->max_nid);
38 	ASSERT(f2fs_test_bit(nid, nm_i->nid_bitmap));
39 
40 	f2fs_clear_bit(nid, nm_i->nid_bitmap);
41 }
42 
43 void set_data_blkaddr(struct dnode_of_data *dn)
44 {
45 	__le32 *addr_array;
46 	struct f2fs_node *node_blk = dn->node_blk;
47 	unsigned int ofs_in_node = dn->ofs_in_node;
48 
49 	addr_array = blkaddr_in_node(node_blk);
50 	addr_array[ofs_in_node] = cpu_to_le32(dn->data_blkaddr);
51 	if (dn->node_blk != dn->inode_blk)
52 		dn->ndirty = 1;
53 	else
54 		dn->idirty = 1;
55 }
56 
57 /*
58  * In this function, we get a new node blk, and write back
59  * node_blk would be sloadd in RAM, linked by dn->node_blk
60  */
61 block_t new_node_block(struct f2fs_sb_info *sbi,
62 				struct dnode_of_data *dn, unsigned int ofs)
63 {
64 	struct f2fs_node *f2fs_inode;
65 	struct f2fs_node *node_blk;
66 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
67 	struct f2fs_summary sum;
68 	struct node_info ni;
69 	block_t blkaddr = NULL_ADDR;
70 	int type;
71 	int ret;
72 
73 	f2fs_inode = dn->inode_blk;
74 
75 	node_blk = calloc(BLOCK_SZ, 1);
76 	ASSERT(node_blk);
77 
78 	node_blk->footer.nid = cpu_to_le32(dn->nid);
79 	node_blk->footer.ino = f2fs_inode->footer.ino;
80 	node_blk->footer.flag = cpu_to_le32(ofs << OFFSET_BIT_SHIFT);
81 	node_blk->footer.cp_ver = ckpt->checkpoint_ver;
82 
83 	type = CURSEG_COLD_NODE;
84 	if (IS_DNODE(node_blk)) {
85 		if (S_ISDIR(le16_to_cpu(f2fs_inode->i.i_mode)))
86 			type = CURSEG_HOT_NODE;
87 		else
88 			type = CURSEG_WARM_NODE;
89 	}
90 
91 	get_node_info(sbi, dn->nid, &ni);
92 	set_summary(&sum, dn->nid, 0, ni.version);
93 	ret = reserve_new_block(sbi, &blkaddr, &sum, type, !ofs);
94 	if (ret) {
95 		free(node_blk);
96 		return 0;
97 	}
98 
99 	/* update nat info */
100 	update_nat_blkaddr(sbi, le32_to_cpu(f2fs_inode->footer.ino),
101 						dn->nid, blkaddr);
102 
103 	dn->node_blk = node_blk;
104 	inc_inode_blocks(dn);
105 	return blkaddr;
106 }
107 
108 /*
109  * get_node_path - Get the index path of pgoff_t block
110  * @offset: offset in the current index node block.
111  * @noffset: NO. of the index block within a file.
112  * return: depth of the index path.
113  *
114  * By default, it sets inline_xattr and inline_data
115  */
116 static int get_node_path(struct f2fs_node *node, long block,
117 				int offset[4], unsigned int noffset[4])
118 {
119 	const long direct_index = ADDRS_PER_INODE(&node->i);
120 	const long direct_blks = ADDRS_PER_BLOCK(&node->i);
121 	const long dptrs_per_blk = NIDS_PER_BLOCK;
122 	const long indirect_blks = ADDRS_PER_BLOCK(&node->i) * NIDS_PER_BLOCK;
123 	const long dindirect_blks = indirect_blks * NIDS_PER_BLOCK;
124 	int n = 0;
125 	int level = 0;
126 
127 	noffset[0] = 0;
128 	if (block < direct_index) {
129 		offset[n] = block;
130 		goto got;
131 	}
132 
133 	block -= direct_index;
134 	if (block < direct_blks) {
135 		offset[n++] = NODE_DIR1_BLOCK;
136 		noffset[n]= 1;
137 		offset[n] = block;
138 		level = 1;
139 		goto got;
140 	}
141 	block -= direct_blks;
142 	if (block < direct_blks) {
143 		offset[n++] = NODE_DIR2_BLOCK;
144 		noffset[n] = 2;
145 		offset[n] = block;
146 		level = 1;
147 		goto got;
148 	}
149 	block -= direct_blks;
150 	if (block < indirect_blks) {
151 		offset[n++] = NODE_IND1_BLOCK;
152 		noffset[n] = 3;
153 		offset[n++] = block / direct_blks;
154 		noffset[n] = 4 + offset[n - 1];
155 		offset[n] = block % direct_blks;
156 		level = 2;
157 		goto got;
158 	}
159 	block -= indirect_blks;
160 	if (block < indirect_blks) {
161 		offset[n++] = NODE_IND2_BLOCK;
162 		noffset[n] = 4 + dptrs_per_blk;
163 		offset[n++] = block / direct_blks;
164 		noffset[n] = 5 + dptrs_per_blk + offset[n - 1];
165 		offset[n] = block % direct_blks;
166 		level = 2;
167 		goto got;
168 	}
169 	block -= indirect_blks;
170 	if (block < dindirect_blks) {
171 		offset[n++] = NODE_DIND_BLOCK;
172 		noffset[n] = 5 + (dptrs_per_blk * 2);
173 		offset[n++] = block / indirect_blks;
174 		noffset[n] = 6 + (dptrs_per_blk * 2) +
175 			offset[n - 1] * (dptrs_per_blk + 1);
176 		offset[n++] = (block / direct_blks) % dptrs_per_blk;
177 		noffset[n] = 7 + (dptrs_per_blk * 2) +
178 			offset[n - 2] * (dptrs_per_blk + 1) +
179 			offset[n - 1];
180 		offset[n] = block % direct_blks;
181 		level = 3;
182 		goto got;
183 	} else {
184 		ASSERT(0);
185 	}
186 got:
187 	return level;
188 }
189 
190 int get_dnode_of_data(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
191 						pgoff_t index, int mode)
192 {
193 	int offset[4];
194 	unsigned int noffset[4];
195 	struct f2fs_node *parent = NULL;
196 	nid_t nids[4];
197 	block_t nblk[4];
198 	struct node_info ni;
199 	int level, i;
200 	int ret;
201 
202 	level = get_node_path(dn->inode_blk, index, offset, noffset);
203 
204 	nids[0] = dn->nid;
205 	parent = dn->inode_blk;
206 	if (level != 0)
207 		nids[1] = get_nid(parent, offset[0], 1);
208 	else
209 		dn->node_blk = dn->inode_blk;
210 
211 	get_node_info(sbi, nids[0], &ni);
212 	nblk[0] = ni.blk_addr;
213 
214 	for (i = 1; i <= level; i++) {
215 		if (!nids[i] && mode == ALLOC_NODE) {
216 			f2fs_alloc_nid(sbi, &nids[i]);
217 
218 			dn->nid = nids[i];
219 
220 			/* Function new_node_blk get a new f2fs_node blk and update*/
221 			/* We should make sure that dn->node_blk == NULL*/
222 			nblk[i] = new_node_block(sbi, dn, noffset[i]);
223 			if (!nblk[i]) {
224 				f2fs_release_nid(sbi, nids[i]);
225 				c.alloc_failed = 1;
226 				return -EINVAL;
227 			}
228 
229 			set_nid(parent, offset[i - 1], nids[i], i == 1);
230 		} else {
231 			/* If Sparse file no read API, */
232 			struct node_info ni;
233 
234 			get_node_info(sbi, nids[i], &ni);
235 			dn->node_blk = calloc(BLOCK_SZ, 1);
236 			ASSERT(dn->node_blk);
237 
238 			ret = dev_read_block(dn->node_blk, ni.blk_addr);
239 			ASSERT(ret >= 0);
240 
241 			nblk[i] = ni.blk_addr;
242 		}
243 
244 		if (mode == ALLOC_NODE){
245 			/* Parent node may have changed */
246 			ret = dev_write_block(parent, nblk[i - 1]);
247 			ASSERT(ret >= 0);
248 		}
249 		if (i != 1)
250 			free(parent);
251 
252 		if (i < level) {
253 			parent = dn->node_blk;
254 			nids[i + 1] = get_nid(parent, offset[i], 0);
255 		}
256 	}
257 
258 	dn->nid = nids[level];
259 	dn->ofs_in_node = offset[level];
260 	dn->data_blkaddr = datablock_addr(dn->node_blk, dn->ofs_in_node);
261 	dn->node_blkaddr = nblk[level];
262 	return 0;
263 }
264