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 */
25struct nilfs_ifile_info {
26	struct nilfs_mdt_info mi;
27	struct nilfs_palloc_cache palloc_cache;
28};
29
30static 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 */
53int 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 */
98int 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
133int 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 */
157int 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 */
185int 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