xref: /openbmc/linux/fs/btrfs/btrfs_inode.h (revision 2572f00d)
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  * The following 3 bits are meant only for the btree inode.
49  * When any of them is set, it means an error happened while writing an
50  * extent buffer belonging to:
51  * 1) a non-log btree
52  * 2) a log btree and first log sub-transaction
53  * 3) a log btree and second log sub-transaction
54  */
55 #define BTRFS_INODE_BTREE_ERR		        12
56 #define BTRFS_INODE_BTREE_LOG1_ERR		13
57 #define BTRFS_INODE_BTREE_LOG2_ERR		14
58 
59 /* in memory btrfs inode */
60 struct btrfs_inode {
61 	/* which subvolume this inode belongs to */
62 	struct btrfs_root *root;
63 
64 	/* key used to find this inode on disk.  This is used by the code
65 	 * to read in roots of subvolumes
66 	 */
67 	struct btrfs_key location;
68 
69 	/*
70 	 * Lock for counters and all fields used to determine if the inode is in
71 	 * the log or not (last_trans, last_sub_trans, last_log_commit,
72 	 * logged_trans).
73 	 */
74 	spinlock_t lock;
75 
76 	/* the extent_tree has caches of all the extent mappings to disk */
77 	struct extent_map_tree extent_tree;
78 
79 	/* the io_tree does range state (DIRTY, LOCKED etc) */
80 	struct extent_io_tree io_tree;
81 
82 	/* special utility tree used to record which mirrors have already been
83 	 * tried when checksums fail for a given block
84 	 */
85 	struct extent_io_tree io_failure_tree;
86 
87 	/* held while logging the inode in tree-log.c */
88 	struct mutex log_mutex;
89 
90 	/* held while doing delalloc reservations */
91 	struct mutex delalloc_mutex;
92 
93 	/* used to order data wrt metadata */
94 	struct btrfs_ordered_inode_tree ordered_tree;
95 
96 	/* list of all the delalloc inodes in the FS.  There are times we need
97 	 * to write all the delalloc pages to disk, and this list is used
98 	 * to walk them all.
99 	 */
100 	struct list_head delalloc_inodes;
101 
102 	/* node for the red-black tree that links inodes in subvolume root */
103 	struct rb_node rb_node;
104 
105 	unsigned long runtime_flags;
106 
107 	/* Keep track of who's O_SYNC/fsyncing currently */
108 	atomic_t sync_writers;
109 
110 	/* full 64 bit generation number, struct vfs_inode doesn't have a big
111 	 * enough field for this.
112 	 */
113 	u64 generation;
114 
115 	/*
116 	 * transid of the trans_handle that last modified this inode
117 	 */
118 	u64 last_trans;
119 
120 	/*
121 	 * transid that last logged this inode
122 	 */
123 	u64 logged_trans;
124 
125 	/*
126 	 * log transid when this inode was last modified
127 	 */
128 	int last_sub_trans;
129 
130 	/* a local copy of root's last_log_commit */
131 	int last_log_commit;
132 
133 	/* total number of bytes pending delalloc, used by stat to calc the
134 	 * real block usage of the file
135 	 */
136 	u64 delalloc_bytes;
137 
138 	/*
139 	 * total number of bytes pending defrag, used by stat to check whether
140 	 * it needs COW.
141 	 */
142 	u64 defrag_bytes;
143 
144 	/*
145 	 * the size of the file stored in the metadata on disk.  data=ordered
146 	 * means the in-memory i_size might be larger than the size on disk
147 	 * because not all the blocks are written yet.
148 	 */
149 	u64 disk_i_size;
150 
151 	/*
152 	 * if this is a directory then index_cnt is the counter for the index
153 	 * number for new files that are created
154 	 */
155 	u64 index_cnt;
156 
157 	/* Cache the directory index number to speed the dir/file remove */
158 	u64 dir_index;
159 
160 	/* the fsync log has some corner cases that mean we have to check
161 	 * directories to see if any unlinks have been done before
162 	 * the directory was logged.  See tree-log.c for all the
163 	 * details
164 	 */
165 	u64 last_unlink_trans;
166 
167 	/*
168 	 * Number of bytes outstanding that are going to need csums.  This is
169 	 * used in ENOSPC accounting.
170 	 */
171 	u64 csum_bytes;
172 
173 	/* flags field from the on disk inode */
174 	u32 flags;
175 
176 	/*
177 	 * Counters to keep track of the number of extent item's we may use due
178 	 * to delalloc and such.  outstanding_extents is the number of extent
179 	 * items we think we'll end up using, and reserved_extents is the number
180 	 * of extent items we've reserved metadata for.
181 	 */
182 	unsigned outstanding_extents;
183 	unsigned reserved_extents;
184 
185 	/*
186 	 * always compress this one file
187 	 */
188 	unsigned force_compress;
189 
190 	struct btrfs_delayed_node *delayed_node;
191 
192 	/* File creation time. */
193 	struct timespec i_otime;
194 
195 	struct inode vfs_inode;
196 };
197 
198 extern unsigned char btrfs_filetype_table[];
199 
200 static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
201 {
202 	return container_of(inode, struct btrfs_inode, vfs_inode);
203 }
204 
205 static inline unsigned long btrfs_inode_hash(u64 objectid,
206 					     const struct btrfs_root *root)
207 {
208 	u64 h = objectid ^ (root->objectid * GOLDEN_RATIO_PRIME);
209 
210 #if BITS_PER_LONG == 32
211 	h = (h >> 32) ^ (h & 0xffffffff);
212 #endif
213 
214 	return (unsigned long)h;
215 }
216 
217 static inline void btrfs_insert_inode_hash(struct inode *inode)
218 {
219 	unsigned long h = btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root);
220 
221 	__insert_inode_hash(inode, h);
222 }
223 
224 static inline u64 btrfs_ino(struct inode *inode)
225 {
226 	u64 ino = BTRFS_I(inode)->location.objectid;
227 
228 	/*
229 	 * !ino: btree_inode
230 	 * type == BTRFS_ROOT_ITEM_KEY: subvol dir
231 	 */
232 	if (!ino || BTRFS_I(inode)->location.type == BTRFS_ROOT_ITEM_KEY)
233 		ino = inode->i_ino;
234 	return ino;
235 }
236 
237 static inline void btrfs_i_size_write(struct inode *inode, u64 size)
238 {
239 	i_size_write(inode, size);
240 	BTRFS_I(inode)->disk_i_size = size;
241 }
242 
243 static inline bool btrfs_is_free_space_inode(struct inode *inode)
244 {
245 	struct btrfs_root *root = BTRFS_I(inode)->root;
246 
247 	if (root == root->fs_info->tree_root &&
248 	    btrfs_ino(inode) != BTRFS_BTREE_INODE_OBJECTID)
249 		return true;
250 	if (BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID)
251 		return true;
252 	return false;
253 }
254 
255 static inline int btrfs_inode_in_log(struct inode *inode, u64 generation)
256 {
257 	int ret = 0;
258 
259 	spin_lock(&BTRFS_I(inode)->lock);
260 	if (BTRFS_I(inode)->logged_trans == generation &&
261 	    BTRFS_I(inode)->last_sub_trans <=
262 	    BTRFS_I(inode)->last_log_commit &&
263 	    BTRFS_I(inode)->last_sub_trans <=
264 	    BTRFS_I(inode)->root->last_log_commit) {
265 		/*
266 		 * After a ranged fsync we might have left some extent maps
267 		 * (that fall outside the fsync's range). So return false
268 		 * here if the list isn't empty, to make sure btrfs_log_inode()
269 		 * will be called and process those extent maps.
270 		 */
271 		smp_mb();
272 		if (list_empty(&BTRFS_I(inode)->extent_tree.modified_extents))
273 			ret = 1;
274 	}
275 	spin_unlock(&BTRFS_I(inode)->lock);
276 	return ret;
277 }
278 
279 #define BTRFS_DIO_ORIG_BIO_SUBMITTED	0x1
280 
281 struct btrfs_dio_private {
282 	struct inode *inode;
283 	unsigned long flags;
284 	u64 logical_offset;
285 	u64 disk_bytenr;
286 	u64 bytes;
287 	void *private;
288 
289 	/* number of bios pending for this dio */
290 	atomic_t pending_bios;
291 
292 	/* IO errors */
293 	int errors;
294 
295 	/* orig_bio is our btrfs_io_bio */
296 	struct bio *orig_bio;
297 
298 	/* dio_bio came from fs/direct-io.c */
299 	struct bio *dio_bio;
300 
301 	/*
302 	 * The original bio may be splited to several sub-bios, this is
303 	 * done during endio of sub-bios
304 	 */
305 	int (*subio_endio)(struct inode *, struct btrfs_io_bio *, int);
306 };
307 
308 /*
309  * Disable DIO read nolock optimization, so new dio readers will be forced
310  * to grab i_mutex. It is used to avoid the endless truncate due to
311  * nonlocked dio read.
312  */
313 static inline void btrfs_inode_block_unlocked_dio(struct inode *inode)
314 {
315 	set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &BTRFS_I(inode)->runtime_flags);
316 	smp_mb();
317 }
318 
319 static inline void btrfs_inode_resume_unlocked_dio(struct inode *inode)
320 {
321 	smp_mb__before_atomic();
322 	clear_bit(BTRFS_INODE_READDIO_NEED_LOCK,
323 		  &BTRFS_I(inode)->runtime_flags);
324 }
325 
326 bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end);
327 
328 #endif
329