xref: /linux/fs/btrfs/raid56.h (revision b83deaa741558babf4b8d51d34f6637ccfff1b26)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2012 Fusion-io  All rights reserved.
4  * Copyright (C) 2012 Intel Corp. All rights reserved.
5  */
6 
7 #ifndef BTRFS_RAID56_H
8 #define BTRFS_RAID56_H
9 
10 static inline int nr_parity_stripes(const struct map_lookup *map)
11 {
12 	if (map->type & BTRFS_BLOCK_GROUP_RAID5)
13 		return 1;
14 	else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
15 		return 2;
16 	else
17 		return 0;
18 }
19 
20 static inline int nr_data_stripes(const struct map_lookup *map)
21 {
22 	return map->num_stripes - nr_parity_stripes(map);
23 }
24 #define RAID5_P_STRIPE ((u64)-2)
25 #define RAID6_Q_STRIPE ((u64)-1)
26 
27 #define is_parity_stripe(x) (((x) == RAID5_P_STRIPE) ||		\
28 			     ((x) == RAID6_Q_STRIPE))
29 
30 struct btrfs_raid_bio;
31 struct btrfs_device;
32 
33 int raid56_parity_recover(struct bio *bio, struct btrfs_io_context *bioc,
34 			  u64 stripe_len, int mirror_num, int generic_io);
35 int raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc,
36 			u64 stripe_len);
37 
38 void raid56_add_scrub_pages(struct btrfs_raid_bio *rbio, struct page *page,
39 			    u64 logical);
40 
41 struct btrfs_raid_bio *raid56_parity_alloc_scrub_rbio(struct bio *bio,
42 				struct btrfs_io_context *bioc, u64 stripe_len,
43 				struct btrfs_device *scrub_dev,
44 				unsigned long *dbitmap, int stripe_nsectors);
45 void raid56_parity_submit_scrub_rbio(struct btrfs_raid_bio *rbio);
46 
47 struct btrfs_raid_bio *
48 raid56_alloc_missing_rbio(struct bio *bio, struct btrfs_io_context *bioc,
49 			  u64 length);
50 void raid56_submit_missing_rbio(struct btrfs_raid_bio *rbio);
51 
52 int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info);
53 void btrfs_free_stripe_hash_table(struct btrfs_fs_info *info);
54 
55 #endif
56