xref: /openbmc/linux/fs/btrfs/volumes.h (revision 565d76cb)
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 };
130 
131 struct btrfs_multi_bio {
132 	atomic_t stripes_pending;
133 	bio_end_io_t *end_io;
134 	struct bio *orig_bio;
135 	void *private;
136 	atomic_t error;
137 	int max_errors;
138 	int num_stripes;
139 	struct btrfs_bio_stripe stripes[];
140 };
141 
142 struct btrfs_device_info {
143 	struct btrfs_device *dev;
144 	u64 dev_offset;
145 	u64 max_avail;
146 };
147 
148 /* Used to sort the devices by max_avail(descending sort) */
149 int btrfs_cmp_device_free_bytes(const void *dev_info1, const void *dev_info2);
150 
151 /*
152  * sort the devices by max_avail, in which max free extent size of each device
153  * is stored.(Descending Sort)
154  */
155 static inline void btrfs_descending_sort_devices(
156 					struct btrfs_device_info *devices,
157 					size_t nr_devices)
158 {
159 	sort(devices, nr_devices, sizeof(struct btrfs_device_info),
160 	     btrfs_cmp_device_free_bytes, NULL);
161 }
162 
163 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
164 				   u64 end, u64 *length);
165 
166 #define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
167 			    (sizeof(struct btrfs_bio_stripe) * (n)))
168 
169 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
170 			   struct btrfs_device *device,
171 			   u64 chunk_tree, u64 chunk_objectid,
172 			   u64 chunk_offset, u64 start, u64 num_bytes);
173 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
174 		    u64 logical, u64 *length,
175 		    struct btrfs_multi_bio **multi_ret, int mirror_num);
176 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
177 		     u64 chunk_start, u64 physical, u64 devid,
178 		     u64 **logical, int *naddrs, int *stripe_len);
179 int btrfs_read_sys_array(struct btrfs_root *root);
180 int btrfs_read_chunk_tree(struct btrfs_root *root);
181 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
182 		      struct btrfs_root *extent_root, u64 type);
183 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
184 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
185 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
186 		  int mirror_num, int async_submit);
187 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf);
188 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
189 		       fmode_t flags, void *holder);
190 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
191 			  struct btrfs_fs_devices **fs_devices_ret);
192 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
193 int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices);
194 int btrfs_add_device(struct btrfs_trans_handle *trans,
195 		     struct btrfs_root *root,
196 		     struct btrfs_device *device);
197 int btrfs_rm_device(struct btrfs_root *root, char *device_path);
198 int btrfs_cleanup_fs_uuids(void);
199 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
200 int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
201 		      u64 logical, struct page *page);
202 int btrfs_grow_device(struct btrfs_trans_handle *trans,
203 		      struct btrfs_device *device, u64 new_size);
204 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
205 				       u8 *uuid, u8 *fsid);
206 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
207 int btrfs_init_new_device(struct btrfs_root *root, char *path);
208 int btrfs_balance(struct btrfs_root *dev_root);
209 void btrfs_unlock_volumes(void);
210 void btrfs_lock_volumes(void);
211 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
212 int find_free_dev_extent(struct btrfs_trans_handle *trans,
213 			 struct btrfs_device *device, u64 num_bytes,
214 			 u64 *start, u64 *max_avail);
215 #endif
216