xref: /openbmc/linux/fs/nilfs2/ifile.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * ifile.c - 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 
19 /**
20  * struct nilfs_ifile_info - on-memory private data of ifile
21  * @mi: on-memory private data of metadata file
22  * @palloc_cache: persistent object allocator cache of ifile
23  */
24 struct nilfs_ifile_info {
25 	struct nilfs_mdt_info mi;
26 	struct nilfs_palloc_cache palloc_cache;
27 };
28 
29 static inline struct nilfs_ifile_info *NILFS_IFILE_I(struct inode *ifile)
30 {
31 	return (struct nilfs_ifile_info *)NILFS_MDT(ifile);
32 }
33 
34 /**
35  * nilfs_ifile_create_inode - create a new disk inode
36  * @ifile: ifile inode
37  * @out_ino: pointer to a variable to store inode number
38  * @out_bh: buffer_head contains newly allocated disk inode
39  *
40  * Return Value: On success, 0 is returned and the newly allocated inode
41  * number is stored in the place pointed by @ino, and buffer_head pointer
42  * that contains newly allocated disk inode structure is stored in the
43  * place pointed by @out_bh
44  * On error, one of the following negative error codes is returned.
45  *
46  * %-EIO - I/O error.
47  *
48  * %-ENOMEM - Insufficient amount of memory available.
49  *
50  * %-ENOSPC - No inode left.
51  */
52 int nilfs_ifile_create_inode(struct inode *ifile, ino_t *out_ino,
53 			     struct buffer_head **out_bh)
54 {
55 	struct nilfs_palloc_req req;
56 	int ret;
57 
58 	req.pr_entry_nr = 0;  /*
59 			       * 0 says find free inode from beginning
60 			       * of a group. dull code!!
61 			       */
62 	req.pr_entry_bh = NULL;
63 
64 	ret = nilfs_palloc_prepare_alloc_entry(ifile, &req);
65 	if (!ret) {
66 		ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 1,
67 						   &req.pr_entry_bh);
68 		if (ret < 0)
69 			nilfs_palloc_abort_alloc_entry(ifile, &req);
70 	}
71 	if (ret < 0) {
72 		brelse(req.pr_entry_bh);
73 		return ret;
74 	}
75 	nilfs_palloc_commit_alloc_entry(ifile, &req);
76 	mark_buffer_dirty(req.pr_entry_bh);
77 	nilfs_mdt_mark_dirty(ifile);
78 	*out_ino = (ino_t)req.pr_entry_nr;
79 	*out_bh = req.pr_entry_bh;
80 	return 0;
81 }
82 
83 /**
84  * nilfs_ifile_delete_inode - delete a disk inode
85  * @ifile: ifile inode
86  * @ino: inode number
87  *
88  * Return Value: On success, 0 is returned. On error, one of the following
89  * negative error codes is returned.
90  *
91  * %-EIO - I/O error.
92  *
93  * %-ENOMEM - Insufficient amount of memory available.
94  *
95  * %-ENOENT - The inode number @ino have not been allocated.
96  */
97 int nilfs_ifile_delete_inode(struct inode *ifile, ino_t ino)
98 {
99 	struct nilfs_palloc_req req = {
100 		.pr_entry_nr = ino, .pr_entry_bh = NULL
101 	};
102 	struct nilfs_inode *raw_inode;
103 	void *kaddr;
104 	int ret;
105 
106 	ret = nilfs_palloc_prepare_free_entry(ifile, &req);
107 	if (!ret) {
108 		ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 0,
109 						   &req.pr_entry_bh);
110 		if (ret < 0)
111 			nilfs_palloc_abort_free_entry(ifile, &req);
112 	}
113 	if (ret < 0) {
114 		brelse(req.pr_entry_bh);
115 		return ret;
116 	}
117 
118 	kaddr = kmap_atomic(req.pr_entry_bh->b_page);
119 	raw_inode = nilfs_palloc_block_get_entry(ifile, req.pr_entry_nr,
120 						 req.pr_entry_bh, kaddr);
121 	raw_inode->i_flags = 0;
122 	kunmap_atomic(kaddr);
123 
124 	mark_buffer_dirty(req.pr_entry_bh);
125 	brelse(req.pr_entry_bh);
126 
127 	nilfs_palloc_commit_free_entry(ifile, &req);
128 
129 	return 0;
130 }
131 
132 int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino,
133 				struct buffer_head **out_bh)
134 {
135 	struct super_block *sb = ifile->i_sb;
136 	int err;
137 
138 	if (unlikely(!NILFS_VALID_INODE(sb, ino))) {
139 		nilfs_error(sb, "bad inode number: %lu", (unsigned long)ino);
140 		return -EINVAL;
141 	}
142 
143 	err = nilfs_palloc_get_entry_block(ifile, ino, 0, out_bh);
144 	if (unlikely(err))
145 		nilfs_msg(sb, KERN_WARNING, "error %d reading inode: ino=%lu",
146 			  err, (unsigned long)ino);
147 	return err;
148 }
149 
150 /**
151  * nilfs_ifile_count_free_inodes - calculate free inodes count
152  * @ifile: ifile inode
153  * @nmaxinodes: current maximum of available inodes count [out]
154  * @nfreeinodes: free inodes count [out]
155  */
156 int nilfs_ifile_count_free_inodes(struct inode *ifile,
157 				    u64 *nmaxinodes, u64 *nfreeinodes)
158 {
159 	u64 nused;
160 	int err;
161 
162 	*nmaxinodes = 0;
163 	*nfreeinodes = 0;
164 
165 	nused = atomic64_read(&NILFS_I(ifile)->i_root->inodes_count);
166 	err = nilfs_palloc_count_max_entries(ifile, nused, nmaxinodes);
167 	if (likely(!err))
168 		*nfreeinodes = *nmaxinodes - nused;
169 	return err;
170 }
171 
172 /**
173  * nilfs_ifile_read - read or get ifile inode
174  * @sb: super block instance
175  * @root: root object
176  * @inode_size: size of an inode
177  * @raw_inode: on-disk ifile inode
178  * @inodep: buffer to store the inode
179  */
180 int nilfs_ifile_read(struct super_block *sb, struct nilfs_root *root,
181 		     size_t inode_size, struct nilfs_inode *raw_inode,
182 		     struct inode **inodep)
183 {
184 	struct inode *ifile;
185 	int err;
186 
187 	ifile = nilfs_iget_locked(sb, root, NILFS_IFILE_INO);
188 	if (unlikely(!ifile))
189 		return -ENOMEM;
190 	if (!(ifile->i_state & I_NEW))
191 		goto out;
192 
193 	err = nilfs_mdt_init(ifile, NILFS_MDT_GFP,
194 			     sizeof(struct nilfs_ifile_info));
195 	if (err)
196 		goto failed;
197 
198 	err = nilfs_palloc_init_blockgroup(ifile, inode_size);
199 	if (err)
200 		goto failed;
201 
202 	nilfs_palloc_setup_cache(ifile, &NILFS_IFILE_I(ifile)->palloc_cache);
203 
204 	err = nilfs_read_inode_common(ifile, raw_inode);
205 	if (err)
206 		goto failed;
207 
208 	unlock_new_inode(ifile);
209  out:
210 	*inodep = ifile;
211 	return 0;
212  failed:
213 	iget_failed(ifile);
214 	return err;
215 }
216