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
52 spinlock_t io_lock;
53
54 struct block_device *bdev;
55
56 /* the mode sent to blkdev_get */
57 fmode_t mode;
58
59 char *name;
60
61 /* the internal btrfs device id */
62 u64 devid;
63
64 /* size of the device */
65 u64 total_bytes;
66
67 /* size of the disk */
68 u64 disk_total_bytes;
69
70 /* bytes used */
71 u64 bytes_used;
72
73 /* optimal io alignment for this device */
74 u32 io_align;
75
76 /* optimal io width for this device */
77 u32 io_width;
78
79 /* minimal io size for this device */
80 u32 sector_size;
81
82 /* type and info about this device */
83 u64 type;
84
85 /* physical drive uuid (or lvm uuid) */
86 u8 uuid[BTRFS_UUID_SIZE];
87
88 struct btrfs_work work;
89 };
90
91 struct btrfs_fs_devices {
92 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
93
94 /* the device with this id has the most recent copy of the super */
95 u64 latest_devid;
96 u64 latest_trans;
97 u64 num_devices;
98 u64 open_devices;
99 u64 rw_devices;
100 u64 missing_devices;
101 u64 total_rw_bytes;
102 struct block_device *latest_bdev;
103
104 /* all of the devices in the FS, protected by a mutex
105 * so we can safely walk it to write out the supers without
106 * worrying about add/remove by the multi-device code
107 */
108 struct mutex device_list_mutex;
109 struct list_head devices;
110
111 /* devices not currently being allocated */
112 struct list_head alloc_list;
113 struct list_head list;
114
115 struct btrfs_fs_devices *seed;
116 int seeding;
117
118 int opened;
119
120 /* set when we find or add a device that doesn't have the
121 * nonrot flag set
122 */
123 int rotating;
124 };
125
126 struct btrfs_bio_stripe {
127 struct btrfs_device *dev;
128 u64 physical;
129 u64 length; /* only used for discard mappings */
130 };
131
132 struct btrfs_multi_bio {
133 atomic_t stripes_pending;
134 bio_end_io_t *end_io;
135 struct bio *orig_bio;
136 void *private;
137 atomic_t error;
138 int max_errors;
139 int num_stripes;
140 struct btrfs_bio_stripe stripes[];
141 };
142
143 struct btrfs_device_info {
144 struct btrfs_device *dev;
145 u64 dev_offset;
146 u64 max_avail;
147 };
148
149 struct map_lookup {
150 u64 type;
151 int io_align;
152 int io_width;
153 int stripe_len;
154 int sector_size;
155 int num_stripes;
156 int sub_stripes;
157 struct btrfs_bio_stripe stripes[];
158 };
159
160 /* Used to sort the devices by max_avail(descending sort) */
161 int btrfs_cmp_device_free_bytes(const void *dev_info1, const void *dev_info2);
162
163 /*
164 * sort the devices by max_avail, in which max free extent size of each device
165 * is stored.(Descending Sort)
166 */
btrfs_descending_sort_devices(struct btrfs_device_info * devices,size_t nr_devices)167 static inline void btrfs_descending_sort_devices(
168 struct btrfs_device_info *devices,
169 size_t nr_devices)
170 {
171 sort(devices, nr_devices, sizeof(struct btrfs_device_info),
172 btrfs_cmp_device_free_bytes, NULL);
173 }
174
175 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
176 u64 end, u64 *length);
177
178 #define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
179 (sizeof(struct btrfs_bio_stripe) * (n)))
180
181 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
182 struct btrfs_device *device,
183 u64 chunk_tree, u64 chunk_objectid,
184 u64 chunk_offset, u64 start, u64 num_bytes);
185 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
186 u64 logical, u64 *length,
187 struct btrfs_multi_bio **multi_ret, int mirror_num);
188 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
189 u64 chunk_start, u64 physical, u64 devid,
190 u64 **logical, int *naddrs, int *stripe_len);
191 int btrfs_read_sys_array(struct btrfs_root *root);
192 int btrfs_read_chunk_tree(struct btrfs_root *root);
193 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
194 struct btrfs_root *extent_root, u64 type);
195 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
196 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
197 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
198 int mirror_num, int async_submit);
199 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf);
200 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
201 fmode_t flags, void *holder);
202 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
203 struct btrfs_fs_devices **fs_devices_ret);
204 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
205 int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices);
206 int btrfs_add_device(struct btrfs_trans_handle *trans,
207 struct btrfs_root *root,
208 struct btrfs_device *device);
209 int btrfs_rm_device(struct btrfs_root *root, char *device_path);
210 int btrfs_cleanup_fs_uuids(void);
211 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
212 int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
213 u64 logical, struct page *page);
214 int btrfs_grow_device(struct btrfs_trans_handle *trans,
215 struct btrfs_device *device, u64 new_size);
216 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
217 u8 *uuid, u8 *fsid);
218 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
219 int btrfs_init_new_device(struct btrfs_root *root, char *path);
220 int btrfs_balance(struct btrfs_root *dev_root);
221 void btrfs_unlock_volumes(void);
222 void btrfs_lock_volumes(void);
223 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
224 int find_free_dev_extent(struct btrfs_trans_handle *trans,
225 struct btrfs_device *device, u64 num_bytes,
226 u64 *start, u64 *max_avail);
227 #endif
228