xref: /openbmc/linux/fs/btrfs/btrfs_inode.h (revision 034f90b3)
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 	/* Lock for counters */
70 	spinlock_t lock;
71 
72 	/* the extent_tree has caches of all the extent mappings to disk */
73 	struct extent_map_tree extent_tree;
74 
75 	/* the io_tree does range state (DIRTY, LOCKED etc) */
76 	struct extent_io_tree io_tree;
77 
78 	/* special utility tree used to record which mirrors have already been
79 	 * tried when checksums fail for a given block
80 	 */
81 	struct extent_io_tree io_failure_tree;
82 
83 	/* held while logging the inode in tree-log.c */
84 	struct mutex log_mutex;
85 
86 	/* held while doing delalloc reservations */
87 	struct mutex delalloc_mutex;
88 
89 	/* used to order data wrt metadata */
90 	struct btrfs_ordered_inode_tree ordered_tree;
91 
92 	/* list of all the delalloc inodes in the FS.  There are times we need
93 	 * to write all the delalloc pages to disk, and this list is used
94 	 * to walk them all.
95 	 */
96 	struct list_head delalloc_inodes;
97 
98 	/* node for the red-black tree that links inodes in subvolume root */
99 	struct rb_node rb_node;
100 
101 	unsigned long runtime_flags;
102 
103 	/* Keep track of who's O_SYNC/fsyncing currently */
104 	atomic_t sync_writers;
105 
106 	/* full 64 bit generation number, struct vfs_inode doesn't have a big
107 	 * enough field for this.
108 	 */
109 	u64 generation;
110 
111 	/*
112 	 * transid of the trans_handle that last modified this inode
113 	 */
114 	u64 last_trans;
115 
116 	/*
117 	 * transid that last logged this inode
118 	 */
119 	u64 logged_trans;
120 
121 	/*
122 	 * log transid when this inode was last modified
123 	 */
124 	int last_sub_trans;
125 
126 	/* a local copy of root's last_log_commit */
127 	int last_log_commit;
128 
129 	/* total number of bytes pending delalloc, used by stat to calc the
130 	 * real block usage of the file
131 	 */
132 	u64 delalloc_bytes;
133 
134 	/*
135 	 * total number of bytes pending defrag, used by stat to check whether
136 	 * it needs COW.
137 	 */
138 	u64 defrag_bytes;
139 
140 	/*
141 	 * the size of the file stored in the metadata on disk.  data=ordered
142 	 * means the in-memory i_size might be larger than the size on disk
143 	 * because not all the blocks are written yet.
144 	 */
145 	u64 disk_i_size;
146 
147 	/*
148 	 * if this is a directory then index_cnt is the counter for the index
149 	 * number for new files that are created
150 	 */
151 	u64 index_cnt;
152 
153 	/* Cache the directory index number to speed the dir/file remove */
154 	u64 dir_index;
155 
156 	/* the fsync log has some corner cases that mean we have to check
157 	 * directories to see if any unlinks have been done before
158 	 * the directory was logged.  See tree-log.c for all the
159 	 * details
160 	 */
161 	u64 last_unlink_trans;
162 
163 	/*
164 	 * Number of bytes outstanding that are going to need csums.  This is
165 	 * used in ENOSPC accounting.
166 	 */
167 	u64 csum_bytes;
168 
169 	/* flags field from the on disk inode */
170 	u32 flags;
171 
172 	/*
173 	 * Counters to keep track of the number of extent item's we may use due
174 	 * to delalloc and such.  outstanding_extents is the number of extent
175 	 * items we think we'll end up using, and reserved_extents is the number
176 	 * of extent items we've reserved metadata for.
177 	 */
178 	unsigned outstanding_extents;
179 	unsigned reserved_extents;
180 
181 	/*
182 	 * always compress this one file
183 	 */
184 	unsigned force_compress;
185 
186 	struct btrfs_delayed_node *delayed_node;
187 
188 	/* File creation time. */
189 	struct timespec i_otime;
190 
191 	struct inode vfs_inode;
192 };
193 
194 extern unsigned char btrfs_filetype_table[];
195 
196 static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
197 {
198 	return container_of(inode, struct btrfs_inode, vfs_inode);
199 }
200 
201 static inline unsigned long btrfs_inode_hash(u64 objectid,
202 					     const struct btrfs_root *root)
203 {
204 	u64 h = objectid ^ (root->objectid * GOLDEN_RATIO_PRIME);
205 
206 #if BITS_PER_LONG == 32
207 	h = (h >> 32) ^ (h & 0xffffffff);
208 #endif
209 
210 	return (unsigned long)h;
211 }
212 
213 static inline void btrfs_insert_inode_hash(struct inode *inode)
214 {
215 	unsigned long h = btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root);
216 
217 	__insert_inode_hash(inode, h);
218 }
219 
220 static inline u64 btrfs_ino(struct inode *inode)
221 {
222 	u64 ino = BTRFS_I(inode)->location.objectid;
223 
224 	/*
225 	 * !ino: btree_inode
226 	 * type == BTRFS_ROOT_ITEM_KEY: subvol dir
227 	 */
228 	if (!ino || BTRFS_I(inode)->location.type == BTRFS_ROOT_ITEM_KEY)
229 		ino = inode->i_ino;
230 	return ino;
231 }
232 
233 static inline void btrfs_i_size_write(struct inode *inode, u64 size)
234 {
235 	i_size_write(inode, size);
236 	BTRFS_I(inode)->disk_i_size = size;
237 }
238 
239 static inline bool btrfs_is_free_space_inode(struct inode *inode)
240 {
241 	struct btrfs_root *root = BTRFS_I(inode)->root;
242 
243 	if (root == root->fs_info->tree_root &&
244 	    btrfs_ino(inode) != BTRFS_BTREE_INODE_OBJECTID)
245 		return true;
246 	if (BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID)
247 		return true;
248 	return false;
249 }
250 
251 static inline int btrfs_inode_in_log(struct inode *inode, u64 generation)
252 {
253 	if (BTRFS_I(inode)->logged_trans == generation &&
254 	    BTRFS_I(inode)->last_sub_trans <=
255 	    BTRFS_I(inode)->last_log_commit &&
256 	    BTRFS_I(inode)->last_sub_trans <=
257 	    BTRFS_I(inode)->root->last_log_commit) {
258 		/*
259 		 * After a ranged fsync we might have left some extent maps
260 		 * (that fall outside the fsync's range). So return false
261 		 * here if the list isn't empty, to make sure btrfs_log_inode()
262 		 * will be called and process those extent maps.
263 		 */
264 		smp_mb();
265 		if (list_empty(&BTRFS_I(inode)->extent_tree.modified_extents))
266 			return 1;
267 	}
268 	return 0;
269 }
270 
271 #define BTRFS_DIO_ORIG_BIO_SUBMITTED	0x1
272 
273 struct btrfs_dio_private {
274 	struct inode *inode;
275 	unsigned long flags;
276 	u64 logical_offset;
277 	u64 disk_bytenr;
278 	u64 bytes;
279 	void *private;
280 
281 	/* number of bios pending for this dio */
282 	atomic_t pending_bios;
283 
284 	/* IO errors */
285 	int errors;
286 
287 	/* orig_bio is our btrfs_io_bio */
288 	struct bio *orig_bio;
289 
290 	/* dio_bio came from fs/direct-io.c */
291 	struct bio *dio_bio;
292 
293 	/*
294 	 * The original bio may be splited to several sub-bios, this is
295 	 * done during endio of sub-bios
296 	 */
297 	int (*subio_endio)(struct inode *, struct btrfs_io_bio *, int);
298 };
299 
300 /*
301  * Disable DIO read nolock optimization, so new dio readers will be forced
302  * to grab i_mutex. It is used to avoid the endless truncate due to
303  * nonlocked dio read.
304  */
305 static inline void btrfs_inode_block_unlocked_dio(struct inode *inode)
306 {
307 	set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &BTRFS_I(inode)->runtime_flags);
308 	smp_mb();
309 }
310 
311 static inline void btrfs_inode_resume_unlocked_dio(struct inode *inode)
312 {
313 	smp_mb__before_atomic();
314 	clear_bit(BTRFS_INODE_READDIO_NEED_LOCK,
315 		  &BTRFS_I(inode)->runtime_flags);
316 }
317 
318 bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end);
319 
320 #endif
321