Commit | Line | Data |
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a3d93f70 | 1 | /* |
047180f2 | 2 | * gcinode.c - dummy inodes to buffer blocks for garbage collection |
a3d93f70 RK |
3 | * |
4 | * Copyright (C) 2005-2008 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 Seiji Kihara <kihara@osrg.net>, Amagai Yoshiji <amagai@osrg.net>, | |
21 | * and Ryusuke Konishi <ryusuke@osrg.net>. | |
22 | * Revised by Ryusuke Konishi <ryusuke@osrg.net>. | |
23 | * | |
24 | */ | |
047180f2 RK |
25 | /* |
26 | * This file adds the cache of on-disk blocks to be moved in garbage | |
27 | * collection. The disk blocks are held with dummy inodes (called | |
28 | * gcinodes), and this file provides lookup function of the dummy | |
29 | * inodes and their buffer read function. | |
30 | * | |
047180f2 RK |
31 | * Buffers and pages held by the dummy inodes will be released each |
32 | * time after they are copied to a new log. Dirty blocks made on the | |
33 | * current generation and the blocks to be moved by GC never overlap | |
34 | * because the dirty blocks make a new generation; they rather must be | |
35 | * written individually. | |
36 | */ | |
a3d93f70 RK |
37 | |
38 | #include <linux/buffer_head.h> | |
39 | #include <linux/mpage.h> | |
40 | #include <linux/hash.h> | |
5a0e3ad6 | 41 | #include <linux/slab.h> |
a3d93f70 RK |
42 | #include <linux/swap.h> |
43 | #include "nilfs.h" | |
05d0e94b RK |
44 | #include "btree.h" |
45 | #include "btnode.h" | |
a3d93f70 RK |
46 | #include "page.h" |
47 | #include "mdt.h" | |
48 | #include "dat.h" | |
49 | #include "ifile.h" | |
50 | ||
7f09410b | 51 | static const struct address_space_operations def_gcinode_aops = { |
fa032744 | 52 | }; |
a3d93f70 RK |
53 | |
54 | /* | |
55 | * nilfs_gccache_submit_read_data() - add data buffer and submit read request | |
56 | * @inode - gc inode | |
57 | * @blkoff - dummy offset treated as the key for the page cache | |
58 | * @pbn - physical block number of the block | |
59 | * @vbn - virtual block number of the block, 0 for non-virtual block | |
60 | * @out_bh - indirect pointer to a buffer_head struct to receive the results | |
61 | * | |
62 | * Description: nilfs_gccache_submit_read_data() registers the data buffer | |
63 | * specified by @pbn to the GC pagecache with the key @blkoff. | |
64 | * This function sets @vbn (@pbn if @vbn is zero) in b_blocknr of the buffer. | |
65 | * | |
66 | * Return Value: On success, 0 is returned. On Error, one of the following | |
67 | * negative error code is returned. | |
68 | * | |
69 | * %-EIO - I/O error. | |
70 | * | |
71 | * %-ENOMEM - Insufficient amount of memory available. | |
72 | * | |
73 | * %-ENOENT - The block specified with @pbn does not exist. | |
74 | */ | |
75 | int nilfs_gccache_submit_read_data(struct inode *inode, sector_t blkoff, | |
76 | sector_t pbn, __u64 vbn, | |
77 | struct buffer_head **out_bh) | |
78 | { | |
79 | struct buffer_head *bh; | |
80 | int err; | |
81 | ||
82 | bh = nilfs_grab_buffer(inode, inode->i_mapping, blkoff, 0); | |
83 | if (unlikely(!bh)) | |
84 | return -ENOMEM; | |
85 | ||
86 | if (buffer_uptodate(bh)) | |
87 | goto out; | |
88 | ||
89 | if (pbn == 0) { | |
90 | struct inode *dat_inode = NILFS_I_NILFS(inode)->ns_dat; | |
91 | /* use original dat, not gc dat. */ | |
92 | err = nilfs_dat_translate(dat_inode, vbn, &pbn); | |
93 | if (unlikely(err)) { /* -EIO, -ENOMEM, -ENOENT */ | |
94 | brelse(bh); | |
95 | goto failed; | |
96 | } | |
97 | } | |
98 | ||
99 | lock_buffer(bh); | |
100 | if (buffer_uptodate(bh)) { | |
101 | unlock_buffer(bh); | |
102 | goto out; | |
103 | } | |
104 | ||
105 | if (!buffer_mapped(bh)) { | |
106 | bh->b_bdev = NILFS_I_NILFS(inode)->ns_bdev; | |
107 | set_buffer_mapped(bh); | |
108 | } | |
109 | bh->b_blocknr = pbn; | |
110 | bh->b_end_io = end_buffer_read_sync; | |
111 | get_bh(bh); | |
112 | submit_bh(READ, bh); | |
113 | if (vbn) | |
114 | bh->b_blocknr = vbn; | |
115 | out: | |
116 | err = 0; | |
117 | *out_bh = bh; | |
118 | ||
119 | failed: | |
120 | unlock_page(bh->b_page); | |
121 | page_cache_release(bh->b_page); | |
122 | return err; | |
123 | } | |
124 | ||
125 | /* | |
126 | * nilfs_gccache_submit_read_node() - add node buffer and submit read request | |
127 | * @inode - gc inode | |
128 | * @pbn - physical block number for the block | |
129 | * @vbn - virtual block number for the block | |
130 | * @out_bh - indirect pointer to a buffer_head struct to receive the results | |
131 | * | |
132 | * Description: nilfs_gccache_submit_read_node() registers the node buffer | |
133 | * specified by @vbn to the GC pagecache. @pbn can be supplied by the | |
134 | * caller to avoid translation of the disk block address. | |
135 | * | |
136 | * Return Value: On success, 0 is returned. On Error, one of the following | |
137 | * negative error code is returned. | |
138 | * | |
139 | * %-EIO - I/O error. | |
140 | * | |
141 | * %-ENOMEM - Insufficient amount of memory available. | |
142 | */ | |
143 | int nilfs_gccache_submit_read_node(struct inode *inode, sector_t pbn, | |
144 | __u64 vbn, struct buffer_head **out_bh) | |
145 | { | |
26dfdd8e RK |
146 | int ret; |
147 | ||
148 | ret = nilfs_btnode_submit_block(&NILFS_I(inode)->i_btnode_cache, | |
149 | vbn ? : pbn, pbn, READ, out_bh, &pbn); | |
a3d93f70 RK |
150 | if (ret == -EEXIST) /* internal code (cache hit) */ |
151 | ret = 0; | |
152 | return ret; | |
153 | } | |
154 | ||
155 | int nilfs_gccache_wait_and_mark_dirty(struct buffer_head *bh) | |
156 | { | |
157 | wait_on_buffer(bh); | |
158 | if (!buffer_uptodate(bh)) | |
159 | return -EIO; | |
160 | if (buffer_dirty(bh)) | |
161 | return -EEXIST; | |
162 | ||
1d5385b9 RK |
163 | if (buffer_nilfs_node(bh)) { |
164 | if (nilfs_btree_broken_node_block(bh)) { | |
165 | clear_buffer_uptodate(bh); | |
166 | return -EIO; | |
167 | } | |
a3d93f70 | 168 | nilfs_btnode_mark_dirty(bh); |
1d5385b9 | 169 | } else { |
adbb39b5 | 170 | nilfs_mark_buffer_dirty(bh); |
1d5385b9 | 171 | } |
a3d93f70 RK |
172 | return 0; |
173 | } | |
174 | ||
263d90ce | 175 | int nilfs_init_gcinode(struct inode *inode) |
a3d93f70 | 176 | { |
263d90ce | 177 | struct nilfs_inode_info *ii = NILFS_I(inode); |
a3d93f70 | 178 | |
adbb39b5 RK |
179 | inode->i_mode = S_IFREG; |
180 | mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS); | |
181 | inode->i_mapping->a_ops = &def_gcinode_aops; | |
182 | inode->i_mapping->backing_dev_info = inode->i_sb->s_bdi; | |
a3d93f70 | 183 | |
adbb39b5 RK |
184 | ii->i_flags = 0; |
185 | nilfs_bmap_init_gc(ii->i_bmap); | |
a3d93f70 | 186 | |
adbb39b5 | 187 | return 0; |
a3d93f70 RK |
188 | } |
189 | ||
263d90ce RK |
190 | /** |
191 | * nilfs_remove_all_gcinodes() - remove all unprocessed gc inodes | |
a3d93f70 | 192 | */ |
263d90ce | 193 | void nilfs_remove_all_gcinodes(struct the_nilfs *nilfs) |
a3d93f70 | 194 | { |
263d90ce RK |
195 | struct list_head *head = &nilfs->ns_gc_inodes; |
196 | struct nilfs_inode_info *ii; | |
a3d93f70 | 197 | |
263d90ce RK |
198 | while (!list_empty(head)) { |
199 | ii = list_first_entry(head, struct nilfs_inode_info, i_dirty); | |
200 | list_del_init(&ii->i_dirty); | |
201 | iput(&ii->vfs_inode); | |
a3d93f70 RK |
202 | } |
203 | } |