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 	/* readahead state */
97 	spinlock_t reada_lock;
98 	atomic_t reada_in_flight;
99 	u64 reada_next;
100 	struct reada_zone *reada_curr_zone;
101 	struct radix_tree_root reada_zones;
102 	struct radix_tree_root reada_extents;
103 
104 	/* for sending down flush barriers */
105 	struct bio *flush_bio;
106 	struct completion flush_wait;
107 	int nobarriers;
108 
109 };
110 
111 struct btrfs_fs_devices {
112 	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
113 
114 	/* the device with this id has the most recent copy of the super */
115 	u64 latest_devid;
116 	u64 latest_trans;
117 	u64 num_devices;
118 	u64 open_devices;
119 	u64 rw_devices;
120 	u64 missing_devices;
121 	u64 total_rw_bytes;
122 	u64 num_can_discard;
123 	struct block_device *latest_bdev;
124 
125 	/* all of the devices in the FS, protected by a mutex
126 	 * so we can safely walk it to write out the supers without
127 	 * worrying about add/remove by the multi-device code
128 	 */
129 	struct mutex device_list_mutex;
130 	struct list_head devices;
131 
132 	/* devices not currently being allocated */
133 	struct list_head alloc_list;
134 	struct list_head list;
135 
136 	struct btrfs_fs_devices *seed;
137 	int seeding;
138 
139 	int opened;
140 
141 	/* set when we find or add a device that doesn't have the
142 	 * nonrot flag set
143 	 */
144 	int rotating;
145 };
146 
147 struct btrfs_bio_stripe {
148 	struct btrfs_device *dev;
149 	u64 physical;
150 	u64 length; /* only used for discard mappings */
151 };
152 
153 struct btrfs_bio;
154 typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
155 
156 struct btrfs_bio {
157 	atomic_t stripes_pending;
158 	bio_end_io_t *end_io;
159 	struct bio *orig_bio;
160 	void *private;
161 	atomic_t error;
162 	int max_errors;
163 	int num_stripes;
164 	int mirror_num;
165 	struct btrfs_bio_stripe stripes[];
166 };
167 
168 struct btrfs_device_info {
169 	struct btrfs_device *dev;
170 	u64 dev_offset;
171 	u64 max_avail;
172 	u64 total_avail;
173 };
174 
175 struct map_lookup {
176 	u64 type;
177 	int io_align;
178 	int io_width;
179 	int stripe_len;
180 	int sector_size;
181 	int num_stripes;
182 	int sub_stripes;
183 	struct btrfs_bio_stripe stripes[];
184 };
185 
186 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
187 			    (sizeof(struct btrfs_bio_stripe) * (n)))
188 
189 /*
190  * Restriper's general type filter
191  */
192 #define BTRFS_BALANCE_DATA		(1ULL << 0)
193 #define BTRFS_BALANCE_SYSTEM		(1ULL << 1)
194 #define BTRFS_BALANCE_METADATA		(1ULL << 2)
195 
196 #define BTRFS_BALANCE_TYPE_MASK		(BTRFS_BALANCE_DATA |	    \
197 					 BTRFS_BALANCE_SYSTEM |	    \
198 					 BTRFS_BALANCE_METADATA)
199 
200 #define BTRFS_BALANCE_FORCE		(1ULL << 3)
201 #define BTRFS_BALANCE_RESUME		(1ULL << 4)
202 
203 /*
204  * Balance filters
205  */
206 #define BTRFS_BALANCE_ARGS_PROFILES	(1ULL << 0)
207 #define BTRFS_BALANCE_ARGS_USAGE	(1ULL << 1)
208 #define BTRFS_BALANCE_ARGS_DEVID	(1ULL << 2)
209 #define BTRFS_BALANCE_ARGS_DRANGE	(1ULL << 3)
210 #define BTRFS_BALANCE_ARGS_VRANGE	(1ULL << 4)
211 
212 /*
213  * Profile changing flags.  When SOFT is set we won't relocate chunk if
214  * it already has the target profile (even though it may be
215  * half-filled).
216  */
217 #define BTRFS_BALANCE_ARGS_CONVERT	(1ULL << 8)
218 #define BTRFS_BALANCE_ARGS_SOFT		(1ULL << 9)
219 
220 struct btrfs_balance_args;
221 struct btrfs_balance_progress;
222 struct btrfs_balance_control {
223 	struct btrfs_fs_info *fs_info;
224 
225 	struct btrfs_balance_args data;
226 	struct btrfs_balance_args meta;
227 	struct btrfs_balance_args sys;
228 
229 	u64 flags;
230 
231 	struct btrfs_balance_progress stat;
232 };
233 
234 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
235 				   u64 end, u64 *length);
236 
237 #define btrfs_bio_size(n) (sizeof(struct btrfs_bio) + \
238 			    (sizeof(struct btrfs_bio_stripe) * (n)))
239 
240 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
241 			   struct btrfs_device *device,
242 			   u64 chunk_tree, u64 chunk_objectid,
243 			   u64 chunk_offset, u64 start, u64 num_bytes);
244 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
245 		    u64 logical, u64 *length,
246 		    struct btrfs_bio **bbio_ret, int mirror_num);
247 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
248 		     u64 chunk_start, u64 physical, u64 devid,
249 		     u64 **logical, int *naddrs, int *stripe_len);
250 int btrfs_read_sys_array(struct btrfs_root *root);
251 int btrfs_read_chunk_tree(struct btrfs_root *root);
252 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
253 		      struct btrfs_root *extent_root, u64 type);
254 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
255 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
256 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
257 		  int mirror_num, int async_submit);
258 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
259 		       fmode_t flags, void *holder);
260 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
261 			  struct btrfs_fs_devices **fs_devices_ret);
262 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
263 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices);
264 int btrfs_add_device(struct btrfs_trans_handle *trans,
265 		     struct btrfs_root *root,
266 		     struct btrfs_device *device);
267 int btrfs_rm_device(struct btrfs_root *root, char *device_path);
268 void btrfs_cleanup_fs_uuids(void);
269 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
270 int btrfs_grow_device(struct btrfs_trans_handle *trans,
271 		      struct btrfs_device *device, u64 new_size);
272 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
273 				       u8 *uuid, u8 *fsid);
274 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
275 int btrfs_init_new_device(struct btrfs_root *root, char *path);
276 int btrfs_balance(struct btrfs_balance_control *bctl,
277 		  struct btrfs_ioctl_balance_args *bargs);
278 int btrfs_recover_balance(struct btrfs_root *tree_root);
279 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
280 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
281 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
282 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
283 			 u64 *start, u64 *max_avail);
284 #endif
285