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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 RK |
52 | .sync_page = block_sync_page, |
53 | }; | |
a3d93f70 RK |
54 | |
55 | /* | |
56 | * nilfs_gccache_submit_read_data() - add data buffer and submit read request | |
57 | * @inode - gc inode | |
58 | * @blkoff - dummy offset treated as the key for the page cache | |
59 | * @pbn - physical block number of the block | |
60 | * @vbn - virtual block number of the block, 0 for non-virtual block | |
61 | * @out_bh - indirect pointer to a buffer_head struct to receive the results | |
62 | * | |
63 | * Description: nilfs_gccache_submit_read_data() registers the data buffer | |
64 | * specified by @pbn to the GC pagecache with the key @blkoff. | |
65 | * This function sets @vbn (@pbn if @vbn is zero) in b_blocknr of the buffer. | |
66 | * | |
67 | * Return Value: On success, 0 is returned. On Error, one of the following | |
68 | * negative error code is returned. | |
69 | * | |
70 | * %-EIO - I/O error. | |
71 | * | |
72 | * %-ENOMEM - Insufficient amount of memory available. | |
73 | * | |
74 | * %-ENOENT - The block specified with @pbn does not exist. | |
75 | */ | |
76 | int nilfs_gccache_submit_read_data(struct inode *inode, sector_t blkoff, | |
77 | sector_t pbn, __u64 vbn, | |
78 | struct buffer_head **out_bh) | |
79 | { | |
80 | struct buffer_head *bh; | |
81 | int err; | |
82 | ||
83 | bh = nilfs_grab_buffer(inode, inode->i_mapping, blkoff, 0); | |
84 | if (unlikely(!bh)) | |
85 | return -ENOMEM; | |
86 | ||
87 | if (buffer_uptodate(bh)) | |
88 | goto out; | |
89 | ||
90 | if (pbn == 0) { | |
91 | struct inode *dat_inode = NILFS_I_NILFS(inode)->ns_dat; | |
92 | /* use original dat, not gc dat. */ | |
93 | err = nilfs_dat_translate(dat_inode, vbn, &pbn); | |
94 | if (unlikely(err)) { /* -EIO, -ENOMEM, -ENOENT */ | |
95 | brelse(bh); | |
96 | goto failed; | |
97 | } | |
98 | } | |
99 | ||
100 | lock_buffer(bh); | |
101 | if (buffer_uptodate(bh)) { | |
102 | unlock_buffer(bh); | |
103 | goto out; | |
104 | } | |
105 | ||
106 | if (!buffer_mapped(bh)) { | |
107 | bh->b_bdev = NILFS_I_NILFS(inode)->ns_bdev; | |
108 | set_buffer_mapped(bh); | |
109 | } | |
110 | bh->b_blocknr = pbn; | |
111 | bh->b_end_io = end_buffer_read_sync; | |
112 | get_bh(bh); | |
113 | submit_bh(READ, bh); | |
114 | if (vbn) | |
115 | bh->b_blocknr = vbn; | |
116 | out: | |
117 | err = 0; | |
118 | *out_bh = bh; | |
119 | ||
120 | failed: | |
121 | unlock_page(bh->b_page); | |
122 | page_cache_release(bh->b_page); | |
123 | return err; | |
124 | } | |
125 | ||
126 | /* | |
127 | * nilfs_gccache_submit_read_node() - add node buffer and submit read request | |
128 | * @inode - gc inode | |
129 | * @pbn - physical block number for the block | |
130 | * @vbn - virtual block number for the block | |
131 | * @out_bh - indirect pointer to a buffer_head struct to receive the results | |
132 | * | |
133 | * Description: nilfs_gccache_submit_read_node() registers the node buffer | |
134 | * specified by @vbn to the GC pagecache. @pbn can be supplied by the | |
135 | * caller to avoid translation of the disk block address. | |
136 | * | |
137 | * Return Value: On success, 0 is returned. On Error, one of the following | |
138 | * negative error code is returned. | |
139 | * | |
140 | * %-EIO - I/O error. | |
141 | * | |
142 | * %-ENOMEM - Insufficient amount of memory available. | |
143 | */ | |
144 | int nilfs_gccache_submit_read_node(struct inode *inode, sector_t pbn, | |
145 | __u64 vbn, struct buffer_head **out_bh) | |
146 | { | |
26dfdd8e RK |
147 | int ret; |
148 | ||
149 | ret = nilfs_btnode_submit_block(&NILFS_I(inode)->i_btnode_cache, | |
150 | vbn ? : pbn, pbn, READ, out_bh, &pbn); | |
a3d93f70 RK |
151 | if (ret == -EEXIST) /* internal code (cache hit) */ |
152 | ret = 0; | |
153 | return ret; | |
154 | } | |
155 | ||
156 | int nilfs_gccache_wait_and_mark_dirty(struct buffer_head *bh) | |
157 | { | |
158 | wait_on_buffer(bh); | |
159 | if (!buffer_uptodate(bh)) | |
160 | return -EIO; | |
161 | if (buffer_dirty(bh)) | |
162 | return -EEXIST; | |
163 | ||
1d5385b9 RK |
164 | if (buffer_nilfs_node(bh)) { |
165 | if (nilfs_btree_broken_node_block(bh)) { | |
166 | clear_buffer_uptodate(bh); | |
167 | return -EIO; | |
168 | } | |
a3d93f70 | 169 | nilfs_btnode_mark_dirty(bh); |
1d5385b9 | 170 | } else { |
adbb39b5 | 171 | nilfs_mark_buffer_dirty(bh); |
1d5385b9 | 172 | } |
a3d93f70 RK |
173 | return 0; |
174 | } | |
175 | ||
263d90ce | 176 | int nilfs_init_gcinode(struct inode *inode) |
a3d93f70 | 177 | { |
263d90ce RK |
178 | struct nilfs_inode_info *ii = NILFS_I(inode); |
179 | struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs; | |
a3d93f70 | 180 | |
adbb39b5 RK |
181 | inode->i_mode = S_IFREG; |
182 | mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS); | |
183 | inode->i_mapping->a_ops = &def_gcinode_aops; | |
184 | inode->i_mapping->backing_dev_info = inode->i_sb->s_bdi; | |
a3d93f70 | 185 | |
adbb39b5 RK |
186 | ii->i_flags = 0; |
187 | nilfs_bmap_init_gc(ii->i_bmap); | |
a3d93f70 | 188 | |
adbb39b5 RK |
189 | /* |
190 | * Add the inode to GC inode list. Garbage Collection | |
191 | * is serialized and no two processes manipulate the | |
192 | * list simultaneously. | |
193 | */ | |
194 | igrab(inode); | |
195 | list_add(&NILFS_I(inode)->i_dirty, &nilfs->ns_gc_inodes); | |
196 | ||
197 | return 0; | |
a3d93f70 RK |
198 | } |
199 | ||
263d90ce RK |
200 | /** |
201 | * nilfs_remove_all_gcinodes() - remove all unprocessed gc inodes | |
a3d93f70 | 202 | */ |
263d90ce | 203 | void nilfs_remove_all_gcinodes(struct the_nilfs *nilfs) |
a3d93f70 | 204 | { |
263d90ce RK |
205 | struct list_head *head = &nilfs->ns_gc_inodes; |
206 | struct nilfs_inode_info *ii; | |
a3d93f70 | 207 | |
263d90ce RK |
208 | while (!list_empty(head)) { |
209 | ii = list_first_entry(head, struct nilfs_inode_info, i_dirty); | |
210 | list_del_init(&ii->i_dirty); | |
211 | iput(&ii->vfs_inode); | |
a3d93f70 RK |
212 | } |
213 | } |