xref: /linux/fs/btrfs/btrfs_inode.h (revision 2fe05e1139a555ae91f00a812cb9520e7d3022ab)
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 	/*
59 	 * Lock for counters and all fields used to determine if the inode is in
60 	 * the log or not (last_trans, last_sub_trans, last_log_commit,
61 	 * logged_trans).
62 	 */
63 	spinlock_t lock;
64 
65 	/* the extent_tree has caches of all the extent mappings to disk */
66 	struct extent_map_tree extent_tree;
67 
68 	/* the io_tree does range state (DIRTY, LOCKED etc) */
69 	struct extent_io_tree io_tree;
70 
71 	/* special utility tree used to record which mirrors have already been
72 	 * tried when checksums fail for a given block
73 	 */
74 	struct extent_io_tree io_failure_tree;
75 
76 	/* held while logging the inode in tree-log.c */
77 	struct mutex log_mutex;
78 
79 	/* held while doing delalloc reservations */
80 	struct mutex delalloc_mutex;
81 
82 	/* used to order data wrt metadata */
83 	struct btrfs_ordered_inode_tree ordered_tree;
84 
85 	/* list of all the delalloc inodes in the FS.  There are times we need
86 	 * to write all the delalloc pages to disk, and this list is used
87 	 * to walk them all.
88 	 */
89 	struct list_head delalloc_inodes;
90 
91 	/* node for the red-black tree that links inodes in subvolume root */
92 	struct rb_node rb_node;
93 
94 	unsigned long runtime_flags;
95 
96 	/* Keep track of who's O_SYNC/fsyncing currently */
97 	atomic_t sync_writers;
98 
99 	/* full 64 bit generation number, struct vfs_inode doesn't have a big
100 	 * enough field for this.
101 	 */
102 	u64 generation;
103 
104 	/*
105 	 * transid of the trans_handle that last modified this inode
106 	 */
107 	u64 last_trans;
108 
109 	/*
110 	 * transid that last logged this inode
111 	 */
112 	u64 logged_trans;
113 
114 	/*
115 	 * log transid when this inode was last modified
116 	 */
117 	int last_sub_trans;
118 
119 	/* a local copy of root's last_log_commit */
120 	int last_log_commit;
121 
122 	/* total number of bytes pending delalloc, used by stat to calc the
123 	 * real block usage of the file
124 	 */
125 	u64 delalloc_bytes;
126 
127 	/*
128 	 * Total number of bytes pending delalloc that fall within a file
129 	 * range that is either a hole or beyond EOF (and no prealloc extent
130 	 * exists in the range). This is always <= delalloc_bytes.
131 	 */
132 	u64 new_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 	/* Hook into fs_info->delayed_iputs */
192 	struct list_head delayed_iput;
193 	long delayed_iput_count;
194 
195 	/*
196 	 * To avoid races between lockless (i_mutex not held) direct IO writes
197 	 * and concurrent fsync requests. Direct IO writes must acquire read
198 	 * access on this semaphore for creating an extent map and its
199 	 * corresponding ordered extent. The fast fsync path must acquire write
200 	 * access on this semaphore before it collects ordered extents and
201 	 * extent maps.
202 	 */
203 	struct rw_semaphore dio_sem;
204 
205 	struct inode vfs_inode;
206 };
207 
208 extern unsigned char btrfs_filetype_table[];
209 
210 static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
211 {
212 	return container_of(inode, struct btrfs_inode, vfs_inode);
213 }
214 
215 static inline unsigned long btrfs_inode_hash(u64 objectid,
216 					     const struct btrfs_root *root)
217 {
218 	u64 h = objectid ^ (root->objectid * GOLDEN_RATIO_PRIME);
219 
220 #if BITS_PER_LONG == 32
221 	h = (h >> 32) ^ (h & 0xffffffff);
222 #endif
223 
224 	return (unsigned long)h;
225 }
226 
227 static inline void btrfs_insert_inode_hash(struct inode *inode)
228 {
229 	unsigned long h = btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root);
230 
231 	__insert_inode_hash(inode, h);
232 }
233 
234 static inline u64 btrfs_ino(struct btrfs_inode *inode)
235 {
236 	u64 ino = inode->location.objectid;
237 
238 	/*
239 	 * !ino: btree_inode
240 	 * type == BTRFS_ROOT_ITEM_KEY: subvol dir
241 	 */
242 	if (!ino || inode->location.type == BTRFS_ROOT_ITEM_KEY)
243 		ino = inode->vfs_inode.i_ino;
244 	return ino;
245 }
246 
247 static inline void btrfs_i_size_write(struct btrfs_inode *inode, u64 size)
248 {
249 	i_size_write(&inode->vfs_inode, size);
250 	inode->disk_i_size = size;
251 }
252 
253 static inline bool btrfs_is_free_space_inode(struct btrfs_inode *inode)
254 {
255 	struct btrfs_root *root = inode->root;
256 
257 	if (root == root->fs_info->tree_root &&
258 	    btrfs_ino(inode) != BTRFS_BTREE_INODE_OBJECTID)
259 		return true;
260 	if (inode->location.objectid == BTRFS_FREE_INO_OBJECTID)
261 		return true;
262 	return false;
263 }
264 
265 static inline int btrfs_inode_in_log(struct btrfs_inode *inode, u64 generation)
266 {
267 	int ret = 0;
268 
269 	spin_lock(&inode->lock);
270 	if (inode->logged_trans == generation &&
271 	    inode->last_sub_trans <= inode->last_log_commit &&
272 	    inode->last_sub_trans <= inode->root->last_log_commit) {
273 		/*
274 		 * After a ranged fsync we might have left some extent maps
275 		 * (that fall outside the fsync's range). So return false
276 		 * here if the list isn't empty, to make sure btrfs_log_inode()
277 		 * will be called and process those extent maps.
278 		 */
279 		smp_mb();
280 		if (list_empty(&inode->extent_tree.modified_extents))
281 			ret = 1;
282 	}
283 	spin_unlock(&inode->lock);
284 	return ret;
285 }
286 
287 #define BTRFS_DIO_ORIG_BIO_SUBMITTED	0x1
288 
289 struct btrfs_dio_private {
290 	struct inode *inode;
291 	unsigned long flags;
292 	u64 logical_offset;
293 	u64 disk_bytenr;
294 	u64 bytes;
295 	void *private;
296 
297 	/* number of bios pending for this dio */
298 	atomic_t pending_bios;
299 
300 	/* IO errors */
301 	int errors;
302 
303 	/* orig_bio is our btrfs_io_bio */
304 	struct bio *orig_bio;
305 
306 	/* dio_bio came from fs/direct-io.c */
307 	struct bio *dio_bio;
308 
309 	/*
310 	 * The original bio may be split to several sub-bios, this is
311 	 * done during endio of sub-bios
312 	 */
313 	blk_status_t (*subio_endio)(struct inode *, struct btrfs_io_bio *,
314 			blk_status_t);
315 };
316 
317 /*
318  * Disable DIO read nolock optimization, so new dio readers will be forced
319  * to grab i_mutex. It is used to avoid the endless truncate due to
320  * nonlocked dio read.
321  */
322 static inline void btrfs_inode_block_unlocked_dio(struct btrfs_inode *inode)
323 {
324 	set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags);
325 	smp_mb();
326 }
327 
328 static inline void btrfs_inode_resume_unlocked_dio(struct btrfs_inode *inode)
329 {
330 	smp_mb__before_atomic();
331 	clear_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags);
332 }
333 
334 static inline void btrfs_print_data_csum_error(struct btrfs_inode *inode,
335 		u64 logical_start, u32 csum, u32 csum_expected, int mirror_num)
336 {
337 	struct btrfs_root *root = inode->root;
338 
339 	/* Output minus objectid, which is more meaningful */
340 	if (root->objectid >= BTRFS_LAST_FREE_OBJECTID)
341 		btrfs_warn_rl(root->fs_info,
342 	"csum failed root %lld ino %lld off %llu csum 0x%08x expected csum 0x%08x mirror %d",
343 			root->objectid, btrfs_ino(inode),
344 			logical_start, csum, csum_expected, mirror_num);
345 	else
346 		btrfs_warn_rl(root->fs_info,
347 	"csum failed root %llu ino %llu off %llu csum 0x%08x expected csum 0x%08x mirror %d",
348 			root->objectid, btrfs_ino(inode),
349 			logical_start, csum, csum_expected, mirror_num);
350 }
351 
352 bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end);
353 
354 #endif
355