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 */
60struct 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
198extern unsigned char btrfs_filetype_table[];
199
200static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
201{
202	return container_of(inode, struct btrfs_inode, vfs_inode);
203}
204
205static 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
217static 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
224static 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
237static 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
243static 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
255static 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
281struct 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 */
313static 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
319static 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
326bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end);
327
328#endif
329