xref: /openbmc/linux/fs/btrfs/btrfs_inode.h (revision 82e6fdd6)
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_HAS_ORPHAN_ITEM		4
40 #define BTRFS_INODE_HAS_ASYNC_EXTENT		5
41 #define BTRFS_INODE_NEEDS_FULL_SYNC		6
42 #define BTRFS_INODE_COPY_EVERYTHING		7
43 #define BTRFS_INODE_IN_DELALLOC_LIST		8
44 #define BTRFS_INODE_READDIO_NEED_LOCK		9
45 #define BTRFS_INODE_HAS_PROPS		        10
46 
47 /* in memory btrfs inode */
48 struct btrfs_inode {
49 	/* which subvolume this inode belongs to */
50 	struct btrfs_root *root;
51 
52 	/* key used to find this inode on disk.  This is used by the code
53 	 * to read in roots of subvolumes
54 	 */
55 	struct btrfs_key location;
56 
57 	/*
58 	 * Lock for counters and all fields used to determine if the inode is in
59 	 * the log or not (last_trans, last_sub_trans, last_log_commit,
60 	 * logged_trans).
61 	 */
62 	spinlock_t lock;
63 
64 	/* the extent_tree has caches of all the extent mappings to disk */
65 	struct extent_map_tree extent_tree;
66 
67 	/* the io_tree does range state (DIRTY, LOCKED etc) */
68 	struct extent_io_tree io_tree;
69 
70 	/* special utility tree used to record which mirrors have already been
71 	 * tried when checksums fail for a given block
72 	 */
73 	struct extent_io_tree io_failure_tree;
74 
75 	/* held while logging the inode in tree-log.c */
76 	struct mutex log_mutex;
77 
78 	/* held while doing delalloc reservations */
79 	struct mutex delalloc_mutex;
80 
81 	/* used to order data wrt metadata */
82 	struct btrfs_ordered_inode_tree ordered_tree;
83 
84 	/* list of all the delalloc inodes in the FS.  There are times we need
85 	 * to write all the delalloc pages to disk, and this list is used
86 	 * to walk them all.
87 	 */
88 	struct list_head delalloc_inodes;
89 
90 	/* node for the red-black tree that links inodes in subvolume root */
91 	struct rb_node rb_node;
92 
93 	unsigned long runtime_flags;
94 
95 	/* Keep track of who's O_SYNC/fsyncing currently */
96 	atomic_t sync_writers;
97 
98 	/* full 64 bit generation number, struct vfs_inode doesn't have a big
99 	 * enough field for this.
100 	 */
101 	u64 generation;
102 
103 	/*
104 	 * transid of the trans_handle that last modified this inode
105 	 */
106 	u64 last_trans;
107 
108 	/*
109 	 * transid that last logged this inode
110 	 */
111 	u64 logged_trans;
112 
113 	/*
114 	 * log transid when this inode was last modified
115 	 */
116 	int last_sub_trans;
117 
118 	/* a local copy of root's last_log_commit */
119 	int last_log_commit;
120 
121 	/* total number of bytes pending delalloc, used by stat to calc the
122 	 * real block usage of the file
123 	 */
124 	u64 delalloc_bytes;
125 
126 	/*
127 	 * Total number of bytes pending delalloc that fall within a file
128 	 * range that is either a hole or beyond EOF (and no prealloc extent
129 	 * exists in the range). This is always <= delalloc_bytes.
130 	 */
131 	u64 new_delalloc_bytes;
132 
133 	/*
134 	 * total number of bytes pending defrag, used by stat to check whether
135 	 * it needs COW.
136 	 */
137 	u64 defrag_bytes;
138 
139 	/*
140 	 * the size of the file stored in the metadata on disk.  data=ordered
141 	 * means the in-memory i_size might be larger than the size on disk
142 	 * because not all the blocks are written yet.
143 	 */
144 	u64 disk_i_size;
145 
146 	/*
147 	 * if this is a directory then index_cnt is the counter for the index
148 	 * number for new files that are created
149 	 */
150 	u64 index_cnt;
151 
152 	/* Cache the directory index number to speed the dir/file remove */
153 	u64 dir_index;
154 
155 	/* the fsync log has some corner cases that mean we have to check
156 	 * directories to see if any unlinks have been done before
157 	 * the directory was logged.  See tree-log.c for all the
158 	 * details
159 	 */
160 	u64 last_unlink_trans;
161 
162 	/*
163 	 * Number of bytes outstanding that are going to need csums.  This is
164 	 * used in ENOSPC accounting.
165 	 */
166 	u64 csum_bytes;
167 
168 	/* flags field from the on disk inode */
169 	u32 flags;
170 
171 	/*
172 	 * Counters to keep track of the number of extent item's we may use due
173 	 * to delalloc and such.  outstanding_extents is the number of extent
174 	 * items we think we'll end up using, and reserved_extents is the number
175 	 * of extent items we've reserved metadata for.
176 	 */
177 	unsigned outstanding_extents;
178 
179 	struct btrfs_block_rsv block_rsv;
180 
181 	/*
182 	 * Cached values of inode properties
183 	 */
184 	unsigned prop_compress;		/* per-file compression algorithm */
185 	/*
186 	 * Force compression on the file using the defrag ioctl, could be
187 	 * different from prop_compress and takes precedence if set
188 	 */
189 	unsigned defrag_compress;
190 
191 	struct btrfs_delayed_node *delayed_node;
192 
193 	/* File creation time. */
194 	struct timespec i_otime;
195 
196 	/* Hook into fs_info->delayed_iputs */
197 	struct list_head delayed_iput;
198 	long delayed_iput_count;
199 
200 	/*
201 	 * To avoid races between lockless (i_mutex not held) direct IO writes
202 	 * and concurrent fsync requests. Direct IO writes must acquire read
203 	 * access on this semaphore for creating an extent map and its
204 	 * corresponding ordered extent. The fast fsync path must acquire write
205 	 * access on this semaphore before it collects ordered extents and
206 	 * extent maps.
207 	 */
208 	struct rw_semaphore dio_sem;
209 
210 	struct inode vfs_inode;
211 };
212 
213 extern unsigned char btrfs_filetype_table[];
214 
215 static inline struct btrfs_inode *BTRFS_I(const struct inode *inode)
216 {
217 	return container_of(inode, struct btrfs_inode, vfs_inode);
218 }
219 
220 static inline unsigned long btrfs_inode_hash(u64 objectid,
221 					     const struct btrfs_root *root)
222 {
223 	u64 h = objectid ^ (root->objectid * GOLDEN_RATIO_PRIME);
224 
225 #if BITS_PER_LONG == 32
226 	h = (h >> 32) ^ (h & 0xffffffff);
227 #endif
228 
229 	return (unsigned long)h;
230 }
231 
232 static inline void btrfs_insert_inode_hash(struct inode *inode)
233 {
234 	unsigned long h = btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root);
235 
236 	__insert_inode_hash(inode, h);
237 }
238 
239 static inline u64 btrfs_ino(const struct btrfs_inode *inode)
240 {
241 	u64 ino = inode->location.objectid;
242 
243 	/*
244 	 * !ino: btree_inode
245 	 * type == BTRFS_ROOT_ITEM_KEY: subvol dir
246 	 */
247 	if (!ino || inode->location.type == BTRFS_ROOT_ITEM_KEY)
248 		ino = inode->vfs_inode.i_ino;
249 	return ino;
250 }
251 
252 static inline void btrfs_i_size_write(struct btrfs_inode *inode, u64 size)
253 {
254 	i_size_write(&inode->vfs_inode, size);
255 	inode->disk_i_size = size;
256 }
257 
258 static inline bool btrfs_is_free_space_inode(struct btrfs_inode *inode)
259 {
260 	struct btrfs_root *root = inode->root;
261 
262 	if (root == root->fs_info->tree_root &&
263 	    btrfs_ino(inode) != BTRFS_BTREE_INODE_OBJECTID)
264 		return true;
265 	if (inode->location.objectid == BTRFS_FREE_INO_OBJECTID)
266 		return true;
267 	return false;
268 }
269 
270 static inline void btrfs_mod_outstanding_extents(struct btrfs_inode *inode,
271 						 int mod)
272 {
273 	lockdep_assert_held(&inode->lock);
274 	inode->outstanding_extents += mod;
275 	if (btrfs_is_free_space_inode(inode))
276 		return;
277 	trace_btrfs_inode_mod_outstanding_extents(inode->root, btrfs_ino(inode),
278 						  mod);
279 }
280 
281 static inline int btrfs_inode_in_log(struct btrfs_inode *inode, u64 generation)
282 {
283 	int ret = 0;
284 
285 	spin_lock(&inode->lock);
286 	if (inode->logged_trans == generation &&
287 	    inode->last_sub_trans <= inode->last_log_commit &&
288 	    inode->last_sub_trans <= inode->root->last_log_commit) {
289 		/*
290 		 * After a ranged fsync we might have left some extent maps
291 		 * (that fall outside the fsync's range). So return false
292 		 * here if the list isn't empty, to make sure btrfs_log_inode()
293 		 * will be called and process those extent maps.
294 		 */
295 		smp_mb();
296 		if (list_empty(&inode->extent_tree.modified_extents))
297 			ret = 1;
298 	}
299 	spin_unlock(&inode->lock);
300 	return ret;
301 }
302 
303 #define BTRFS_DIO_ORIG_BIO_SUBMITTED	0x1
304 
305 struct btrfs_dio_private {
306 	struct inode *inode;
307 	unsigned long flags;
308 	u64 logical_offset;
309 	u64 disk_bytenr;
310 	u64 bytes;
311 	void *private;
312 
313 	/* number of bios pending for this dio */
314 	atomic_t pending_bios;
315 
316 	/* IO errors */
317 	int errors;
318 
319 	/* orig_bio is our btrfs_io_bio */
320 	struct bio *orig_bio;
321 
322 	/* dio_bio came from fs/direct-io.c */
323 	struct bio *dio_bio;
324 
325 	/*
326 	 * The original bio may be split to several sub-bios, this is
327 	 * done during endio of sub-bios
328 	 */
329 	blk_status_t (*subio_endio)(struct inode *, struct btrfs_io_bio *,
330 			blk_status_t);
331 };
332 
333 /*
334  * Disable DIO read nolock optimization, so new dio readers will be forced
335  * to grab i_mutex. It is used to avoid the endless truncate due to
336  * nonlocked dio read.
337  */
338 static inline void btrfs_inode_block_unlocked_dio(struct btrfs_inode *inode)
339 {
340 	set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags);
341 	smp_mb();
342 }
343 
344 static inline void btrfs_inode_resume_unlocked_dio(struct btrfs_inode *inode)
345 {
346 	smp_mb__before_atomic();
347 	clear_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags);
348 }
349 
350 static inline void btrfs_print_data_csum_error(struct btrfs_inode *inode,
351 		u64 logical_start, u32 csum, u32 csum_expected, int mirror_num)
352 {
353 	struct btrfs_root *root = inode->root;
354 
355 	/* Output minus objectid, which is more meaningful */
356 	if (root->objectid >= BTRFS_LAST_FREE_OBJECTID)
357 		btrfs_warn_rl(root->fs_info,
358 	"csum failed root %lld ino %lld off %llu csum 0x%08x expected csum 0x%08x mirror %d",
359 			root->objectid, btrfs_ino(inode),
360 			logical_start, csum, csum_expected, mirror_num);
361 	else
362 		btrfs_warn_rl(root->fs_info,
363 	"csum failed root %llu ino %llu off %llu csum 0x%08x expected csum 0x%08x mirror %d",
364 			root->objectid, btrfs_ino(inode),
365 			logical_start, csum, csum_expected, mirror_num);
366 }
367 
368 bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end);
369 
370 #endif
371