xref: /openbmc/linux/fs/btrfs/volumes.h (revision 9c1f8594)
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 <linux/sort.h>
24 #include "async-thread.h"
25 
26 #define BTRFS_STRIPE_LEN	(64 * 1024)
27 
28 struct buffer_head;
29 struct btrfs_pending_bios {
30 	struct bio *head;
31 	struct bio *tail;
32 };
33 
34 struct btrfs_device {
35 	struct list_head dev_list;
36 	struct list_head dev_alloc_list;
37 	struct btrfs_fs_devices *fs_devices;
38 	struct btrfs_root *dev_root;
39 
40 	/* regular prio bios */
41 	struct btrfs_pending_bios pending_bios;
42 	/* WRITE_SYNC bios */
43 	struct btrfs_pending_bios pending_sync_bios;
44 
45 	int running_pending;
46 	u64 generation;
47 
48 	int writeable;
49 	int in_fs_metadata;
50 	int missing;
51 	int can_discard;
52 
53 	spinlock_t io_lock;
54 
55 	struct block_device *bdev;
56 
57 	/* the mode sent to blkdev_get */
58 	fmode_t mode;
59 
60 	char *name;
61 
62 	/* the internal btrfs device id */
63 	u64 devid;
64 
65 	/* size of the device */
66 	u64 total_bytes;
67 
68 	/* size of the disk */
69 	u64 disk_total_bytes;
70 
71 	/* bytes used */
72 	u64 bytes_used;
73 
74 	/* optimal io alignment for this device */
75 	u32 io_align;
76 
77 	/* optimal io width for this device */
78 	u32 io_width;
79 
80 	/* minimal io size for this device */
81 	u32 sector_size;
82 
83 	/* type and info about this device */
84 	u64 type;
85 
86 	/* physical drive uuid (or lvm uuid) */
87 	u8 uuid[BTRFS_UUID_SIZE];
88 
89 	/* per-device scrub information */
90 	struct scrub_dev *scrub_device;
91 
92 	struct btrfs_work work;
93 	struct rcu_head rcu;
94 	struct work_struct rcu_work;
95 };
96 
97 struct btrfs_fs_devices {
98 	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
99 
100 	/* the device with this id has the most recent copy of the super */
101 	u64 latest_devid;
102 	u64 latest_trans;
103 	u64 num_devices;
104 	u64 open_devices;
105 	u64 rw_devices;
106 	u64 missing_devices;
107 	u64 total_rw_bytes;
108 	u64 num_can_discard;
109 	struct block_device *latest_bdev;
110 
111 	/* all of the devices in the FS, protected by a mutex
112 	 * so we can safely walk it to write out the supers without
113 	 * worrying about add/remove by the multi-device code
114 	 */
115 	struct mutex device_list_mutex;
116 	struct list_head devices;
117 
118 	/* devices not currently being allocated */
119 	struct list_head alloc_list;
120 	struct list_head list;
121 
122 	struct btrfs_fs_devices *seed;
123 	int seeding;
124 
125 	int opened;
126 
127 	/* set when we find or add a device that doesn't have the
128 	 * nonrot flag set
129 	 */
130 	int rotating;
131 };
132 
133 struct btrfs_bio_stripe {
134 	struct btrfs_device *dev;
135 	u64 physical;
136 	u64 length; /* only used for discard mappings */
137 };
138 
139 struct btrfs_multi_bio {
140 	atomic_t stripes_pending;
141 	bio_end_io_t *end_io;
142 	struct bio *orig_bio;
143 	void *private;
144 	atomic_t error;
145 	int max_errors;
146 	int num_stripes;
147 	struct btrfs_bio_stripe stripes[];
148 };
149 
150 struct btrfs_device_info {
151 	struct btrfs_device *dev;
152 	u64 dev_offset;
153 	u64 max_avail;
154 	u64 total_avail;
155 };
156 
157 struct map_lookup {
158 	u64 type;
159 	int io_align;
160 	int io_width;
161 	int stripe_len;
162 	int sector_size;
163 	int num_stripes;
164 	int sub_stripes;
165 	struct btrfs_bio_stripe stripes[];
166 };
167 
168 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
169 			    (sizeof(struct btrfs_bio_stripe) * (n)))
170 
171 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
172 				   u64 end, u64 *length);
173 
174 #define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
175 			    (sizeof(struct btrfs_bio_stripe) * (n)))
176 
177 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
178 			   struct btrfs_device *device,
179 			   u64 chunk_tree, u64 chunk_objectid,
180 			   u64 chunk_offset, u64 start, u64 num_bytes);
181 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
182 		    u64 logical, u64 *length,
183 		    struct btrfs_multi_bio **multi_ret, int mirror_num);
184 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
185 		     u64 chunk_start, u64 physical, u64 devid,
186 		     u64 **logical, int *naddrs, int *stripe_len);
187 int btrfs_read_sys_array(struct btrfs_root *root);
188 int btrfs_read_chunk_tree(struct btrfs_root *root);
189 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
190 		      struct btrfs_root *extent_root, u64 type);
191 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
192 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
193 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
194 		  int mirror_num, int async_submit);
195 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
196 		       fmode_t flags, void *holder);
197 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
198 			  struct btrfs_fs_devices **fs_devices_ret);
199 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
200 int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices);
201 int btrfs_add_device(struct btrfs_trans_handle *trans,
202 		     struct btrfs_root *root,
203 		     struct btrfs_device *device);
204 int btrfs_rm_device(struct btrfs_root *root, char *device_path);
205 int btrfs_cleanup_fs_uuids(void);
206 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
207 int btrfs_grow_device(struct btrfs_trans_handle *trans,
208 		      struct btrfs_device *device, u64 new_size);
209 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
210 				       u8 *uuid, u8 *fsid);
211 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
212 int btrfs_init_new_device(struct btrfs_root *root, char *path);
213 int btrfs_balance(struct btrfs_root *dev_root);
214 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
215 int find_free_dev_extent(struct btrfs_trans_handle *trans,
216 			 struct btrfs_device *device, u64 num_bytes,
217 			 u64 *start, u64 *max_avail);
218 #endif
219