xref: /linux/fs/nilfs2/ifile.c (revision c8bfe3fad4f86a029da7157bae9699c816f0c309)
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 = 0;  /*
60 			       * 0 says find free inode from beginning
61 			       * of a group. dull code!!
62 			       */
63 	req.pr_entry_bh = NULL;
64 
65 	ret = nilfs_palloc_prepare_alloc_entry(ifile, &req);
66 	if (!ret) {
67 		ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 1,
68 						   &req.pr_entry_bh);
69 		if (ret < 0)
70 			nilfs_palloc_abort_alloc_entry(ifile, &req);
71 	}
72 	if (ret < 0) {
73 		brelse(req.pr_entry_bh);
74 		return ret;
75 	}
76 	nilfs_palloc_commit_alloc_entry(ifile, &req);
77 	mark_buffer_dirty(req.pr_entry_bh);
78 	nilfs_mdt_mark_dirty(ifile);
79 	*out_ino = (ino_t)req.pr_entry_nr;
80 	*out_bh = req.pr_entry_bh;
81 	return 0;
82 }
83 
84 /**
85  * nilfs_ifile_delete_inode - delete a disk inode
86  * @ifile: ifile inode
87  * @ino: inode number
88  *
89  * Return Value: On success, 0 is returned. On error, one of the following
90  * negative error codes is returned.
91  *
92  * %-EIO - I/O error.
93  *
94  * %-ENOMEM - Insufficient amount of memory available.
95  *
96  * %-ENOENT - The inode number @ino have not been allocated.
97  */
98 int nilfs_ifile_delete_inode(struct inode *ifile, ino_t ino)
99 {
100 	struct nilfs_palloc_req req = {
101 		.pr_entry_nr = ino, .pr_entry_bh = NULL
102 	};
103 	struct nilfs_inode *raw_inode;
104 	void *kaddr;
105 	int ret;
106 
107 	ret = nilfs_palloc_prepare_free_entry(ifile, &req);
108 	if (!ret) {
109 		ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 0,
110 						   &req.pr_entry_bh);
111 		if (ret < 0)
112 			nilfs_palloc_abort_free_entry(ifile, &req);
113 	}
114 	if (ret < 0) {
115 		brelse(req.pr_entry_bh);
116 		return ret;
117 	}
118 
119 	kaddr = kmap_local_page(req.pr_entry_bh->b_page);
120 	raw_inode = nilfs_palloc_block_get_entry(ifile, req.pr_entry_nr,
121 						 req.pr_entry_bh, kaddr);
122 	raw_inode->i_flags = 0;
123 	kunmap_local(kaddr);
124 
125 	mark_buffer_dirty(req.pr_entry_bh);
126 	brelse(req.pr_entry_bh);
127 
128 	nilfs_palloc_commit_free_entry(ifile, &req);
129 
130 	return 0;
131 }
132 
133 int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino,
134 				struct buffer_head **out_bh)
135 {
136 	struct super_block *sb = ifile->i_sb;
137 	int err;
138 
139 	if (unlikely(!NILFS_VALID_INODE(sb, ino))) {
140 		nilfs_error(sb, "bad inode number: %lu", (unsigned long)ino);
141 		return -EINVAL;
142 	}
143 
144 	err = nilfs_palloc_get_entry_block(ifile, ino, 0, out_bh);
145 	if (unlikely(err))
146 		nilfs_warn(sb, "error %d reading inode: ino=%lu",
147 			   err, (unsigned long)ino);
148 	return err;
149 }
150 
151 /**
152  * nilfs_ifile_count_free_inodes - calculate free inodes count
153  * @ifile: ifile inode
154  * @nmaxinodes: current maximum of available inodes count [out]
155  * @nfreeinodes: free inodes count [out]
156  */
157 int nilfs_ifile_count_free_inodes(struct inode *ifile,
158 				    u64 *nmaxinodes, u64 *nfreeinodes)
159 {
160 	u64 nused;
161 	int err;
162 
163 	*nmaxinodes = 0;
164 	*nfreeinodes = 0;
165 
166 	nused = atomic64_read(&NILFS_I(ifile)->i_root->inodes_count);
167 	err = nilfs_palloc_count_max_entries(ifile, nused, nmaxinodes);
168 	if (likely(!err))
169 		*nfreeinodes = *nmaxinodes - nused;
170 	return err;
171 }
172 
173 /**
174  * nilfs_ifile_read - read or get ifile inode
175  * @sb: super block instance
176  * @root: root object
177  * @cno: number of checkpoint entry to read
178  * @inode_size: size of an inode
179  *
180  * Return: 0 on success, or the following negative error code on failure.
181  * * %-EINVAL	- Invalid checkpoint.
182  * * %-ENOMEM	- Insufficient memory available.
183  * * %-EIO	- I/O error (including metadata corruption).
184  */
185 int nilfs_ifile_read(struct super_block *sb, struct nilfs_root *root,
186 		     __u64 cno, size_t inode_size)
187 {
188 	struct the_nilfs *nilfs;
189 	struct inode *ifile;
190 	int err;
191 
192 	ifile = nilfs_iget_locked(sb, root, NILFS_IFILE_INO);
193 	if (unlikely(!ifile))
194 		return -ENOMEM;
195 	if (!(ifile->i_state & I_NEW))
196 		goto out;
197 
198 	err = nilfs_mdt_init(ifile, NILFS_MDT_GFP,
199 			     sizeof(struct nilfs_ifile_info));
200 	if (err)
201 		goto failed;
202 
203 	err = nilfs_palloc_init_blockgroup(ifile, inode_size);
204 	if (err)
205 		goto failed;
206 
207 	nilfs_palloc_setup_cache(ifile, &NILFS_IFILE_I(ifile)->palloc_cache);
208 
209 	nilfs = sb->s_fs_info;
210 	err = nilfs_cpfile_read_checkpoint(nilfs->ns_cpfile, cno, root, ifile);
211 	if (err)
212 		goto failed;
213 
214 	unlock_new_inode(ifile);
215  out:
216 	return 0;
217  failed:
218 	iget_failed(ifile);
219 	return err;
220 }
221