xref: /openbmc/linux/fs/btrfs/btrfs_inode.h (revision 8a26af30)
1 /*
2  * Copyright (C) 2007 Oracle.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public
6  * License v2 as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public
14  * License along with this program; if not, write to the
15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16  * Boston, MA 021110-1307, USA.
17  */
18 
19 #ifndef __BTRFS_I__
20 #define __BTRFS_I__
21 
22 #include <linux/hash.h>
23 #include "extent_map.h"
24 #include "extent_io.h"
25 #include "ordered-data.h"
26 #include "delayed-inode.h"
27 
28 /*
29  * ordered_data_close is set by truncate when a file that used
30  * to have good data has been truncated to zero.  When it is set
31  * the btrfs file release call will add this inode to the
32  * ordered operations list so that we make sure to flush out any
33  * new data the application may have written before commit.
34  */
35 #define BTRFS_INODE_ORDERED_DATA_CLOSE		0
36 #define BTRFS_INODE_ORPHAN_META_RESERVED	1
37 #define BTRFS_INODE_DUMMY			2
38 #define BTRFS_INODE_IN_DEFRAG			3
39 #define BTRFS_INODE_DELALLOC_META_RESERVED	4
40 #define BTRFS_INODE_HAS_ORPHAN_ITEM		5
41 #define BTRFS_INODE_HAS_ASYNC_EXTENT		6
42 #define BTRFS_INODE_NEEDS_FULL_SYNC		7
43 #define BTRFS_INODE_COPY_EVERYTHING		8
44 #define BTRFS_INODE_IN_DELALLOC_LIST		9
45 #define BTRFS_INODE_READDIO_NEED_LOCK		10
46 #define BTRFS_INODE_HAS_PROPS		        11
47 
48 /* in memory btrfs inode */
49 struct btrfs_inode {
50 	/* which subvolume this inode belongs to */
51 	struct btrfs_root *root;
52 
53 	/* key used to find this inode on disk.  This is used by the code
54 	 * to read in roots of subvolumes
55 	 */
56 	struct btrfs_key location;
57 
58 	/* Lock for counters */
59 	spinlock_t lock;
60 
61 	/* the extent_tree has caches of all the extent mappings to disk */
62 	struct extent_map_tree extent_tree;
63 
64 	/* the io_tree does range state (DIRTY, LOCKED etc) */
65 	struct extent_io_tree io_tree;
66 
67 	/* special utility tree used to record which mirrors have already been
68 	 * tried when checksums fail for a given block
69 	 */
70 	struct extent_io_tree io_failure_tree;
71 
72 	/* held while logging the inode in tree-log.c */
73 	struct mutex log_mutex;
74 
75 	/* held while doing delalloc reservations */
76 	struct mutex delalloc_mutex;
77 
78 	/* used to order data wrt metadata */
79 	struct btrfs_ordered_inode_tree ordered_tree;
80 
81 	/* list of all the delalloc inodes in the FS.  There are times we need
82 	 * to write all the delalloc pages to disk, and this list is used
83 	 * to walk them all.
84 	 */
85 	struct list_head delalloc_inodes;
86 
87 	/*
88 	 * list for tracking inodes that must be sent to disk before a
89 	 * rename or truncate commit
90 	 */
91 	struct list_head ordered_operations;
92 
93 	/* node for the red-black tree that links inodes in subvolume root */
94 	struct rb_node rb_node;
95 
96 	unsigned long runtime_flags;
97 
98 	/* Keep track of who's O_SYNC/fsyncing currently */
99 	atomic_t sync_writers;
100 
101 	/* full 64 bit generation number, struct vfs_inode doesn't have a big
102 	 * enough field for this.
103 	 */
104 	u64 generation;
105 
106 	/*
107 	 * transid of the trans_handle that last modified this inode
108 	 */
109 	u64 last_trans;
110 
111 	/*
112 	 * transid that last logged this inode
113 	 */
114 	u64 logged_trans;
115 
116 	/*
117 	 * log transid when this inode was last modified
118 	 */
119 	int last_sub_trans;
120 
121 	/* a local copy of root's last_log_commit */
122 	int last_log_commit;
123 
124 	/* total number of bytes pending delalloc, used by stat to calc the
125 	 * real block usage of the file
126 	 */
127 	u64 delalloc_bytes;
128 
129 	/*
130 	 * the size of the file stored in the metadata on disk.  data=ordered
131 	 * means the in-memory i_size might be larger than the size on disk
132 	 * because not all the blocks are written yet.
133 	 */
134 	u64 disk_i_size;
135 
136 	/*
137 	 * if this is a directory then index_cnt is the counter for the index
138 	 * number for new files that are created
139 	 */
140 	u64 index_cnt;
141 
142 	/* Cache the directory index number to speed the dir/file remove */
143 	u64 dir_index;
144 
145 	/* the fsync log has some corner cases that mean we have to check
146 	 * directories to see if any unlinks have been done before
147 	 * the directory was logged.  See tree-log.c for all the
148 	 * details
149 	 */
150 	u64 last_unlink_trans;
151 
152 	/*
153 	 * Number of bytes outstanding that are going to need csums.  This is
154 	 * used in ENOSPC accounting.
155 	 */
156 	u64 csum_bytes;
157 
158 	/* flags field from the on disk inode */
159 	u32 flags;
160 
161 	/*
162 	 * Counters to keep track of the number of extent item's we may use due
163 	 * to delalloc and such.  outstanding_extents is the number of extent
164 	 * items we think we'll end up using, and reserved_extents is the number
165 	 * of extent items we've reserved metadata for.
166 	 */
167 	unsigned outstanding_extents;
168 	unsigned reserved_extents;
169 
170 	/*
171 	 * always compress this one file
172 	 */
173 	unsigned force_compress;
174 
175 	struct btrfs_delayed_node *delayed_node;
176 
177 	struct inode vfs_inode;
178 };
179 
180 extern unsigned char btrfs_filetype_table[];
181 
182 static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
183 {
184 	return container_of(inode, struct btrfs_inode, vfs_inode);
185 }
186 
187 static inline unsigned long btrfs_inode_hash(u64 objectid,
188 					     const struct btrfs_root *root)
189 {
190 	u64 h = objectid ^ (root->objectid * GOLDEN_RATIO_PRIME);
191 
192 #if BITS_PER_LONG == 32
193 	h = (h >> 32) ^ (h & 0xffffffff);
194 #endif
195 
196 	return (unsigned long)h;
197 }
198 
199 static inline void btrfs_insert_inode_hash(struct inode *inode)
200 {
201 	unsigned long h = btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root);
202 
203 	__insert_inode_hash(inode, h);
204 }
205 
206 static inline u64 btrfs_ino(struct inode *inode)
207 {
208 	u64 ino = BTRFS_I(inode)->location.objectid;
209 
210 	/*
211 	 * !ino: btree_inode
212 	 * type == BTRFS_ROOT_ITEM_KEY: subvol dir
213 	 */
214 	if (!ino || BTRFS_I(inode)->location.type == BTRFS_ROOT_ITEM_KEY)
215 		ino = inode->i_ino;
216 	return ino;
217 }
218 
219 static inline void btrfs_i_size_write(struct inode *inode, u64 size)
220 {
221 	i_size_write(inode, size);
222 	BTRFS_I(inode)->disk_i_size = size;
223 }
224 
225 static inline bool btrfs_is_free_space_inode(struct inode *inode)
226 {
227 	struct btrfs_root *root = BTRFS_I(inode)->root;
228 
229 	if (root == root->fs_info->tree_root &&
230 	    btrfs_ino(inode) != BTRFS_BTREE_INODE_OBJECTID)
231 		return true;
232 	if (BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID)
233 		return true;
234 	return false;
235 }
236 
237 static inline int btrfs_inode_in_log(struct inode *inode, u64 generation)
238 {
239 	if (BTRFS_I(inode)->logged_trans == generation &&
240 	    BTRFS_I(inode)->last_sub_trans <=
241 	    BTRFS_I(inode)->last_log_commit &&
242 	    BTRFS_I(inode)->last_sub_trans <=
243 	    BTRFS_I(inode)->root->last_log_commit)
244 		return 1;
245 	return 0;
246 }
247 
248 struct btrfs_dio_private {
249 	struct inode *inode;
250 	u64 logical_offset;
251 	u64 disk_bytenr;
252 	u64 bytes;
253 	void *private;
254 
255 	/* number of bios pending for this dio */
256 	atomic_t pending_bios;
257 
258 	/* IO errors */
259 	int errors;
260 
261 	/* orig_bio is our btrfs_io_bio */
262 	struct bio *orig_bio;
263 
264 	/* dio_bio came from fs/direct-io.c */
265 	struct bio *dio_bio;
266 	u8 csum[0];
267 };
268 
269 /*
270  * Disable DIO read nolock optimization, so new dio readers will be forced
271  * to grab i_mutex. It is used to avoid the endless truncate due to
272  * nonlocked dio read.
273  */
274 static inline void btrfs_inode_block_unlocked_dio(struct inode *inode)
275 {
276 	set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &BTRFS_I(inode)->runtime_flags);
277 	smp_mb();
278 }
279 
280 static inline void btrfs_inode_resume_unlocked_dio(struct inode *inode)
281 {
282 	smp_mb__before_atomic();
283 	clear_bit(BTRFS_INODE_READDIO_NEED_LOCK,
284 		  &BTRFS_I(inode)->runtime_flags);
285 }
286 
287 bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end);
288 
289 #endif
290