xref: /linux/fs/nilfs2/ifile.c (revision a06c3fad49a50d5d5eb078f93e70f4d3eca5d5a5)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * NILFS inode file
4  *
5  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
6  *
7  * Written by Amagai Yoshiji.
8  * Revised by Ryusuke Konishi.
9  *
10  */
11 
12 #include <linux/types.h>
13 #include <linux/buffer_head.h>
14 #include "nilfs.h"
15 #include "mdt.h"
16 #include "alloc.h"
17 #include "ifile.h"
18 #include "cpfile.h"
19 
20 /**
21  * struct nilfs_ifile_info - on-memory private data of ifile
22  * @mi: on-memory private data of metadata file
23  * @palloc_cache: persistent object allocator cache of ifile
24  */
25 struct nilfs_ifile_info {
26 	struct nilfs_mdt_info mi;
27 	struct nilfs_palloc_cache palloc_cache;
28 };
29 
30 static inline struct nilfs_ifile_info *NILFS_IFILE_I(struct inode *ifile)
31 {
32 	return (struct nilfs_ifile_info *)NILFS_MDT(ifile);
33 }
34 
35 /**
36  * nilfs_ifile_create_inode - create a new disk inode
37  * @ifile: ifile inode
38  * @out_ino: pointer to a variable to store inode number
39  * @out_bh: buffer_head contains newly allocated disk inode
40  *
41  * Return Value: On success, 0 is returned and the newly allocated inode
42  * number is stored in the place pointed by @ino, and buffer_head pointer
43  * that contains newly allocated disk inode structure is stored in the
44  * place pointed by @out_bh
45  * On error, one of the following negative error codes is returned.
46  *
47  * %-EIO - I/O error.
48  *
49  * %-ENOMEM - Insufficient amount of memory available.
50  *
51  * %-ENOSPC - No inode left.
52  */
53 int nilfs_ifile_create_inode(struct inode *ifile, ino_t *out_ino,
54 			     struct buffer_head **out_bh)
55 {
56 	struct nilfs_palloc_req req;
57 	int ret;
58 
59 	req.pr_entry_nr = NILFS_FIRST_INO(ifile->i_sb);
60 	req.pr_entry_bh = NULL;
61 
62 	ret = nilfs_palloc_prepare_alloc_entry(ifile, &req, false);
63 	if (!ret) {
64 		ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 1,
65 						   &req.pr_entry_bh);
66 		if (ret < 0)
67 			nilfs_palloc_abort_alloc_entry(ifile, &req);
68 	}
69 	if (ret < 0) {
70 		brelse(req.pr_entry_bh);
71 		return ret;
72 	}
73 	nilfs_palloc_commit_alloc_entry(ifile, &req);
74 	mark_buffer_dirty(req.pr_entry_bh);
75 	nilfs_mdt_mark_dirty(ifile);
76 	*out_ino = (ino_t)req.pr_entry_nr;
77 	*out_bh = req.pr_entry_bh;
78 	return 0;
79 }
80 
81 /**
82  * nilfs_ifile_delete_inode - delete a disk inode
83  * @ifile: ifile inode
84  * @ino: inode number
85  *
86  * Return Value: On success, 0 is returned. On error, one of the following
87  * negative error codes is returned.
88  *
89  * %-EIO - I/O error.
90  *
91  * %-ENOMEM - Insufficient amount of memory available.
92  *
93  * %-ENOENT - The inode number @ino have not been allocated.
94  */
95 int nilfs_ifile_delete_inode(struct inode *ifile, ino_t ino)
96 {
97 	struct nilfs_palloc_req req = {
98 		.pr_entry_nr = ino, .pr_entry_bh = NULL
99 	};
100 	struct nilfs_inode *raw_inode;
101 	void *kaddr;
102 	int ret;
103 
104 	ret = nilfs_palloc_prepare_free_entry(ifile, &req);
105 	if (!ret) {
106 		ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 0,
107 						   &req.pr_entry_bh);
108 		if (ret < 0)
109 			nilfs_palloc_abort_free_entry(ifile, &req);
110 	}
111 	if (ret < 0) {
112 		brelse(req.pr_entry_bh);
113 		return ret;
114 	}
115 
116 	kaddr = kmap_local_page(req.pr_entry_bh->b_page);
117 	raw_inode = nilfs_palloc_block_get_entry(ifile, req.pr_entry_nr,
118 						 req.pr_entry_bh, kaddr);
119 	raw_inode->i_flags = 0;
120 	kunmap_local(kaddr);
121 
122 	mark_buffer_dirty(req.pr_entry_bh);
123 	brelse(req.pr_entry_bh);
124 
125 	nilfs_palloc_commit_free_entry(ifile, &req);
126 
127 	return 0;
128 }
129 
130 int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino,
131 				struct buffer_head **out_bh)
132 {
133 	struct super_block *sb = ifile->i_sb;
134 	int err;
135 
136 	if (unlikely(!NILFS_VALID_INODE(sb, ino))) {
137 		nilfs_error(sb, "bad inode number: %lu", (unsigned long)ino);
138 		return -EINVAL;
139 	}
140 
141 	err = nilfs_palloc_get_entry_block(ifile, ino, 0, out_bh);
142 	if (unlikely(err))
143 		nilfs_warn(sb, "error %d reading inode: ino=%lu",
144 			   err, (unsigned long)ino);
145 	return err;
146 }
147 
148 /**
149  * nilfs_ifile_count_free_inodes - calculate free inodes count
150  * @ifile: ifile inode
151  * @nmaxinodes: current maximum of available inodes count [out]
152  * @nfreeinodes: free inodes count [out]
153  */
154 int nilfs_ifile_count_free_inodes(struct inode *ifile,
155 				    u64 *nmaxinodes, u64 *nfreeinodes)
156 {
157 	u64 nused;
158 	int err;
159 
160 	*nmaxinodes = 0;
161 	*nfreeinodes = 0;
162 
163 	nused = atomic64_read(&NILFS_I(ifile)->i_root->inodes_count);
164 	err = nilfs_palloc_count_max_entries(ifile, nused, nmaxinodes);
165 	if (likely(!err))
166 		*nfreeinodes = *nmaxinodes - nused;
167 	return err;
168 }
169 
170 /**
171  * nilfs_ifile_read - read or get ifile inode
172  * @sb: super block instance
173  * @root: root object
174  * @cno: number of checkpoint entry to read
175  * @inode_size: size of an inode
176  *
177  * Return: 0 on success, or the following negative error code on failure.
178  * * %-EINVAL	- Invalid checkpoint.
179  * * %-ENOMEM	- Insufficient memory available.
180  * * %-EIO	- I/O error (including metadata corruption).
181  */
182 int nilfs_ifile_read(struct super_block *sb, struct nilfs_root *root,
183 		     __u64 cno, size_t inode_size)
184 {
185 	struct the_nilfs *nilfs;
186 	struct inode *ifile;
187 	int err;
188 
189 	ifile = nilfs_iget_locked(sb, root, NILFS_IFILE_INO);
190 	if (unlikely(!ifile))
191 		return -ENOMEM;
192 	if (!(ifile->i_state & I_NEW))
193 		goto out;
194 
195 	err = nilfs_mdt_init(ifile, NILFS_MDT_GFP,
196 			     sizeof(struct nilfs_ifile_info));
197 	if (err)
198 		goto failed;
199 
200 	err = nilfs_palloc_init_blockgroup(ifile, inode_size);
201 	if (err)
202 		goto failed;
203 
204 	nilfs_palloc_setup_cache(ifile, &NILFS_IFILE_I(ifile)->palloc_cache);
205 
206 	nilfs = sb->s_fs_info;
207 	err = nilfs_cpfile_read_checkpoint(nilfs->ns_cpfile, cno, root, ifile);
208 	if (err)
209 		goto failed;
210 
211 	unlock_new_inode(ifile);
212  out:
213 	return 0;
214  failed:
215 	iget_failed(ifile);
216 	return err;
217 }
218