xref: /openbmc/linux/fs/nilfs2/ifile.c (revision b627b4ed)
1 /*
2  * ifile.c - NILFS inode file
3  *
4  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  *
20  * Written by Amagai Yoshiji <amagai@osrg.net>.
21  * Revised by Ryusuke Konishi <ryusuke@osrg.net>.
22  *
23  */
24 
25 #include <linux/types.h>
26 #include <linux/buffer_head.h>
27 #include "nilfs.h"
28 #include "mdt.h"
29 #include "alloc.h"
30 #include "ifile.h"
31 
32 /**
33  * nilfs_ifile_create_inode - create a new disk inode
34  * @ifile: ifile inode
35  * @out_ino: pointer to a variable to store inode number
36  * @out_bh: buffer_head contains newly allocated disk inode
37  *
38  * Return Value: On success, 0 is returned and the newly allocated inode
39  * number is stored in the place pointed by @ino, and buffer_head pointer
40  * that contains newly allocated disk inode structure is stored in the
41  * place pointed by @out_bh
42  * On error, one of the following negative error codes is returned.
43  *
44  * %-EIO - I/O error.
45  *
46  * %-ENOMEM - Insufficient amount of memory available.
47  *
48  * %-ENOSPC - No inode left.
49  */
50 int nilfs_ifile_create_inode(struct inode *ifile, ino_t *out_ino,
51 			     struct buffer_head **out_bh)
52 {
53 	struct nilfs_palloc_req req;
54 	int ret;
55 
56 	req.pr_entry_nr = 0;  /* 0 says find free inode from beginning of
57 				 a group. dull code!! */
58 	req.pr_entry_bh = NULL;
59 
60 	ret = nilfs_palloc_prepare_alloc_entry(ifile, &req);
61 	if (!ret) {
62 		ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 1,
63 						   &req.pr_entry_bh);
64 		if (ret < 0)
65 			nilfs_palloc_abort_alloc_entry(ifile, &req);
66 	}
67 	if (ret < 0) {
68 		brelse(req.pr_entry_bh);
69 		return ret;
70 	}
71 	nilfs_palloc_commit_alloc_entry(ifile, &req);
72 	nilfs_mdt_mark_buffer_dirty(req.pr_entry_bh);
73 	nilfs_mdt_mark_dirty(ifile);
74 	*out_ino = (ino_t)req.pr_entry_nr;
75 	*out_bh = req.pr_entry_bh;
76 	return 0;
77 }
78 
79 /**
80  * nilfs_ifile_delete_inode - delete a disk inode
81  * @ifile: ifile inode
82  * @ino: inode number
83  *
84  * Return Value: On success, 0 is returned. On error, one of the following
85  * negative error codes is returned.
86  *
87  * %-EIO - I/O error.
88  *
89  * %-ENOMEM - Insufficient amount of memory available.
90  *
91  * %-ENOENT - The inode number @ino have not been allocated.
92  */
93 int nilfs_ifile_delete_inode(struct inode *ifile, ino_t ino)
94 {
95 	struct nilfs_palloc_req req = {
96 		.pr_entry_nr = ino, .pr_entry_bh = NULL
97 	};
98 	struct nilfs_inode *raw_inode;
99 	void *kaddr;
100 	int ret;
101 
102 	ret = nilfs_palloc_prepare_free_entry(ifile, &req);
103 	if (!ret) {
104 		ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 0,
105 						   &req.pr_entry_bh);
106 		if (ret < 0)
107 			nilfs_palloc_abort_free_entry(ifile, &req);
108 	}
109 	if (ret < 0) {
110 		brelse(req.pr_entry_bh);
111 		return ret;
112 	}
113 
114 	kaddr = kmap_atomic(req.pr_entry_bh->b_page, KM_USER0);
115 	raw_inode = nilfs_palloc_block_get_entry(ifile, req.pr_entry_nr,
116 						 req.pr_entry_bh, kaddr);
117 	raw_inode->i_flags = 0;
118 	kunmap_atomic(kaddr, KM_USER0);
119 
120 	nilfs_mdt_mark_buffer_dirty(req.pr_entry_bh);
121 	brelse(req.pr_entry_bh);
122 
123 	nilfs_palloc_commit_free_entry(ifile, &req);
124 
125 	return 0;
126 }
127 
128 int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino,
129 				struct buffer_head **out_bh)
130 {
131 	struct super_block *sb = ifile->i_sb;
132 	int err;
133 
134 	if (unlikely(!NILFS_VALID_INODE(sb, ino))) {
135 		nilfs_error(sb, __func__, "bad inode number: %lu",
136 			    (unsigned long) ino);
137 		return -EINVAL;
138 	}
139 
140 	err = nilfs_palloc_get_entry_block(ifile, ino, 0, out_bh);
141 	if (unlikely(err)) {
142 		if (err == -EINVAL)
143 			nilfs_error(sb, __func__, "ifile is broken");
144 		else
145 			nilfs_warning(sb, __func__,
146 				      "unable to read inode: %lu",
147 				      (unsigned long) ino);
148 	}
149 	return err;
150 }
151