xref: /linux/fs/btrfs/volumes.h (revision 6ee738610f41b59733f63718f0bdbcba7d3a3f12)
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_VOLUMES_
20 #define __BTRFS_VOLUMES_
21 
22 #include <linux/bio.h>
23 #include "async-thread.h"
24 
25 struct buffer_head;
26 struct btrfs_pending_bios {
27 	struct bio *head;
28 	struct bio *tail;
29 };
30 
31 struct btrfs_device {
32 	struct list_head dev_list;
33 	struct list_head dev_alloc_list;
34 	struct btrfs_fs_devices *fs_devices;
35 	struct btrfs_root *dev_root;
36 
37 	/* regular prio bios */
38 	struct btrfs_pending_bios pending_bios;
39 	/* WRITE_SYNC bios */
40 	struct btrfs_pending_bios pending_sync_bios;
41 
42 	int running_pending;
43 	u64 generation;
44 
45 	int barriers;
46 	int writeable;
47 	int in_fs_metadata;
48 
49 	spinlock_t io_lock;
50 
51 	struct block_device *bdev;
52 
53 	/* the mode sent to open_bdev_exclusive */
54 	fmode_t mode;
55 
56 	char *name;
57 
58 	/* the internal btrfs device id */
59 	u64 devid;
60 
61 	/* size of the device */
62 	u64 total_bytes;
63 
64 	/* size of the disk */
65 	u64 disk_total_bytes;
66 
67 	/* bytes used */
68 	u64 bytes_used;
69 
70 	/* optimal io alignment for this device */
71 	u32 io_align;
72 
73 	/* optimal io width for this device */
74 	u32 io_width;
75 
76 	/* minimal io size for this device */
77 	u32 sector_size;
78 
79 	/* type and info about this device */
80 	u64 type;
81 
82 	/* physical drive uuid (or lvm uuid) */
83 	u8 uuid[BTRFS_UUID_SIZE];
84 
85 	struct btrfs_work work;
86 };
87 
88 struct btrfs_fs_devices {
89 	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
90 
91 	/* the device with this id has the most recent copy of the super */
92 	u64 latest_devid;
93 	u64 latest_trans;
94 	u64 num_devices;
95 	u64 open_devices;
96 	u64 rw_devices;
97 	u64 total_rw_bytes;
98 	struct block_device *latest_bdev;
99 
100 	/* all of the devices in the FS, protected by a mutex
101 	 * so we can safely walk it to write out the supers without
102 	 * worrying about add/remove by the multi-device code
103 	 */
104 	struct mutex device_list_mutex;
105 	struct list_head devices;
106 
107 	/* devices not currently being allocated */
108 	struct list_head alloc_list;
109 	struct list_head list;
110 
111 	struct btrfs_fs_devices *seed;
112 	int seeding;
113 
114 	int opened;
115 
116 	/* set when we find or add a device that doesn't have the
117 	 * nonrot flag set
118 	 */
119 	int rotating;
120 };
121 
122 struct btrfs_bio_stripe {
123 	struct btrfs_device *dev;
124 	u64 physical;
125 };
126 
127 struct btrfs_multi_bio {
128 	atomic_t stripes_pending;
129 	bio_end_io_t *end_io;
130 	struct bio *orig_bio;
131 	void *private;
132 	atomic_t error;
133 	int max_errors;
134 	int num_stripes;
135 	struct btrfs_bio_stripe stripes[];
136 };
137 
138 #define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
139 			    (sizeof(struct btrfs_bio_stripe) * (n)))
140 
141 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
142 			   struct btrfs_device *device,
143 			   u64 chunk_tree, u64 chunk_objectid,
144 			   u64 chunk_offset, u64 start, u64 num_bytes);
145 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
146 		    u64 logical, u64 *length,
147 		    struct btrfs_multi_bio **multi_ret, int mirror_num);
148 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
149 		     u64 chunk_start, u64 physical, u64 devid,
150 		     u64 **logical, int *naddrs, int *stripe_len);
151 int btrfs_read_sys_array(struct btrfs_root *root);
152 int btrfs_read_chunk_tree(struct btrfs_root *root);
153 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
154 		      struct btrfs_root *extent_root, u64 type);
155 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
156 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
157 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
158 		  int mirror_num, int async_submit);
159 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf);
160 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
161 		       fmode_t flags, void *holder);
162 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
163 			  struct btrfs_fs_devices **fs_devices_ret);
164 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
165 int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices);
166 int btrfs_add_device(struct btrfs_trans_handle *trans,
167 		     struct btrfs_root *root,
168 		     struct btrfs_device *device);
169 int btrfs_rm_device(struct btrfs_root *root, char *device_path);
170 int btrfs_cleanup_fs_uuids(void);
171 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
172 int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
173 		      u64 logical, struct page *page);
174 int btrfs_grow_device(struct btrfs_trans_handle *trans,
175 		      struct btrfs_device *device, u64 new_size);
176 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
177 				       u8 *uuid, u8 *fsid);
178 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
179 int btrfs_init_new_device(struct btrfs_root *root, char *path);
180 int btrfs_balance(struct btrfs_root *dev_root);
181 void btrfs_unlock_volumes(void);
182 void btrfs_lock_volumes(void);
183 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
184 int find_free_dev_extent(struct btrfs_trans_handle *trans,
185 			 struct btrfs_device *device, u64 num_bytes,
186 			 u64 *start, u64 *max_avail);
187 #endif
188