• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 defrag, used by stat to check whether
129 	 * it needs COW.
130 	 */
131 	u64 defrag_bytes;
132 
133 	/*
134 	 * the size of the file stored in the metadata on disk.  data=ordered
135 	 * means the in-memory i_size might be larger than the size on disk
136 	 * because not all the blocks are written yet.
137 	 */
138 	u64 disk_i_size;
139 
140 	/*
141 	 * if this is a directory then index_cnt is the counter for the index
142 	 * number for new files that are created
143 	 */
144 	u64 index_cnt;
145 
146 	/* Cache the directory index number to speed the dir/file remove */
147 	u64 dir_index;
148 
149 	/* the fsync log has some corner cases that mean we have to check
150 	 * directories to see if any unlinks have been done before
151 	 * the directory was logged.  See tree-log.c for all the
152 	 * details
153 	 */
154 	u64 last_unlink_trans;
155 
156 	/*
157 	 * Number of bytes outstanding that are going to need csums.  This is
158 	 * used in ENOSPC accounting.
159 	 */
160 	u64 csum_bytes;
161 
162 	/* flags field from the on disk inode */
163 	u32 flags;
164 
165 	/*
166 	 * Counters to keep track of the number of extent item's we may use due
167 	 * to delalloc and such.  outstanding_extents is the number of extent
168 	 * items we think we'll end up using, and reserved_extents is the number
169 	 * of extent items we've reserved metadata for.
170 	 */
171 	unsigned outstanding_extents;
172 	unsigned reserved_extents;
173 
174 	/*
175 	 * always compress this one file
176 	 */
177 	unsigned force_compress;
178 
179 	struct btrfs_delayed_node *delayed_node;
180 
181 	/* File creation time. */
182 	struct timespec i_otime;
183 
184 	/* Hook into fs_info->delayed_iputs */
185 	struct list_head delayed_iput;
186 	long delayed_iput_count;
187 
188 	/*
189 	 * To avoid races between lockless (i_mutex not held) direct IO writes
190 	 * and concurrent fsync requests. Direct IO writes must acquire read
191 	 * access on this semaphore for creating an extent map and its
192 	 * corresponding ordered extent. The fast fsync path must acquire write
193 	 * access on this semaphore before it collects ordered extents and
194 	 * extent maps.
195 	 */
196 	struct rw_semaphore dio_sem;
197 
198 	struct inode vfs_inode;
199 };
200 
201 extern unsigned char btrfs_filetype_table[];
202 
BTRFS_I(struct inode * inode)203 static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
204 {
205 	return container_of(inode, struct btrfs_inode, vfs_inode);
206 }
207 
btrfs_inode_hash(u64 objectid,const struct btrfs_root * root)208 static inline unsigned long btrfs_inode_hash(u64 objectid,
209 					     const struct btrfs_root *root)
210 {
211 	u64 h = objectid ^ (root->objectid * GOLDEN_RATIO_PRIME);
212 
213 #if BITS_PER_LONG == 32
214 	h = (h >> 32) ^ (h & 0xffffffff);
215 #endif
216 
217 	return (unsigned long)h;
218 }
219 
btrfs_insert_inode_hash(struct inode * inode)220 static inline void btrfs_insert_inode_hash(struct inode *inode)
221 {
222 	unsigned long h = btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root);
223 
224 	__insert_inode_hash(inode, h);
225 }
226 
btrfs_ino(struct inode * inode)227 static inline u64 btrfs_ino(struct inode *inode)
228 {
229 	u64 ino = BTRFS_I(inode)->location.objectid;
230 
231 	/*
232 	 * !ino: btree_inode
233 	 * type == BTRFS_ROOT_ITEM_KEY: subvol dir
234 	 */
235 	if (!ino || BTRFS_I(inode)->location.type == BTRFS_ROOT_ITEM_KEY)
236 		ino = inode->i_ino;
237 	return ino;
238 }
239 
btrfs_i_size_write(struct inode * inode,u64 size)240 static inline void btrfs_i_size_write(struct inode *inode, u64 size)
241 {
242 	i_size_write(inode, size);
243 	BTRFS_I(inode)->disk_i_size = size;
244 }
245 
btrfs_is_free_space_inode(struct inode * inode)246 static inline bool btrfs_is_free_space_inode(struct inode *inode)
247 {
248 	struct btrfs_root *root = BTRFS_I(inode)->root;
249 
250 	if (root == root->fs_info->tree_root &&
251 	    btrfs_ino(inode) != BTRFS_BTREE_INODE_OBJECTID)
252 		return true;
253 	if (BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID)
254 		return true;
255 	return false;
256 }
257 
btrfs_inode_in_log(struct inode * inode,u64 generation)258 static inline int btrfs_inode_in_log(struct inode *inode, u64 generation)
259 {
260 	int ret = 0;
261 
262 	spin_lock(&BTRFS_I(inode)->lock);
263 	if (BTRFS_I(inode)->logged_trans == generation &&
264 	    BTRFS_I(inode)->last_sub_trans <=
265 	    BTRFS_I(inode)->last_log_commit &&
266 	    BTRFS_I(inode)->last_sub_trans <=
267 	    BTRFS_I(inode)->root->last_log_commit) {
268 		/*
269 		 * After a ranged fsync we might have left some extent maps
270 		 * (that fall outside the fsync's range). So return false
271 		 * here if the list isn't empty, to make sure btrfs_log_inode()
272 		 * will be called and process those extent maps.
273 		 */
274 		smp_mb();
275 		if (list_empty(&BTRFS_I(inode)->extent_tree.modified_extents))
276 			ret = 1;
277 	}
278 	spin_unlock(&BTRFS_I(inode)->lock);
279 	return ret;
280 }
281 
282 #define BTRFS_DIO_ORIG_BIO_SUBMITTED	0x1
283 
284 struct btrfs_dio_private {
285 	struct inode *inode;
286 	unsigned long flags;
287 	u64 logical_offset;
288 	u64 disk_bytenr;
289 	u64 bytes;
290 	void *private;
291 
292 	/* number of bios pending for this dio */
293 	atomic_t pending_bios;
294 
295 	/* IO errors */
296 	int errors;
297 
298 	/* orig_bio is our btrfs_io_bio */
299 	struct bio *orig_bio;
300 
301 	/* dio_bio came from fs/direct-io.c */
302 	struct bio *dio_bio;
303 
304 	/*
305 	 * The original bio may be split to several sub-bios, this is
306 	 * done during endio of sub-bios
307 	 */
308 	int (*subio_endio)(struct inode *, struct btrfs_io_bio *, int);
309 };
310 
311 /*
312  * Disable DIO read nolock optimization, so new dio readers will be forced
313  * to grab i_mutex. It is used to avoid the endless truncate due to
314  * nonlocked dio read.
315  */
btrfs_inode_block_unlocked_dio(struct inode * inode)316 static inline void btrfs_inode_block_unlocked_dio(struct inode *inode)
317 {
318 	set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &BTRFS_I(inode)->runtime_flags);
319 	smp_mb();
320 }
321 
btrfs_inode_resume_unlocked_dio(struct inode * inode)322 static inline void btrfs_inode_resume_unlocked_dio(struct inode *inode)
323 {
324 	smp_mb__before_atomic();
325 	clear_bit(BTRFS_INODE_READDIO_NEED_LOCK,
326 		  &BTRFS_I(inode)->runtime_flags);
327 }
328 
329 bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end);
330 
331 #endif
332