1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright (C) 2012 Fusion-io All rights reserved.
4 * Copyright (C) 2012 Intel Corp. All rights reserved.
10 #include <linux/workqueue.h>
15 BTRFS_RBIO_READ_REBUILD,
16 BTRFS_RBIO_PARITY_SCRUB,
17 BTRFS_RBIO_REBUILD_MISSING,
20 struct btrfs_raid_bio {
21 struct btrfs_io_context *bioc;
24 * While we're doing RMW on a stripe we put it into a hash table so we
25 * can lock the stripe and merge more rbios into it.
27 struct list_head hash_list;
29 /* LRU list for the stripe cache */
30 struct list_head stripe_cache;
32 /* For scheduling work in the helper threads */
33 struct work_struct work;
36 * bio_list and bio_list_lock are used to add more bios into the stripe
37 * in hopes of avoiding the full RMW
39 struct bio_list bio_list;
40 spinlock_t bio_list_lock;
43 * Also protected by the bio_list_lock, the plug list is used by the
44 * plugging code to collect partial bios while plugged. The stripe
45 * locking code also uses it to hand off the stripe lock to the next
48 struct list_head plug_list;
50 /* Flags that tell us if it is safe to merge with this bio. */
54 * Set if we're doing a parity rebuild for a read from higher up, which
55 * is handled differently from a parity rebuild as part of RMW.
57 enum btrfs_rbio_ops operation;
59 /* How many pages there are for the full stripe including P/Q */
62 /* How many sectors there are for the full stripe including P/Q */
65 /* Number of data stripes (no p/q) */
68 /* Numer of all stripes (including P/Q) */
71 /* How many pages there are for each stripe */
74 /* How many sectors there are for each stripe */
77 /* First bad stripe, -1 means no corruption */
80 /* Second bad stripe (for RAID6 use) */
83 /* Stripe number that we're scrubbing */
87 * Size of all the bios in the bio_list. This helps us decide if the
88 * rbio maps to a full stripe or not.
96 atomic_t stripes_pending;
100 struct work_struct end_io_work;
102 /* Bitmap to record which horizontal stripe has data */
103 unsigned long dbitmap;
105 /* Allocated with stripe_nsectors-many bits for finish_*() calls */
106 unsigned long finish_pbitmap;
109 * These are two arrays of pointers. We allocate the rbio big enough
110 * to hold them both and setup their locations when the rbio is
115 * Pointers to pages that we allocated for reading/writing stripes
116 * directly from the disk (including P/Q).
118 struct page **stripe_pages;
120 /* Pointers to the sectors in the bio_list, for faster lookup */
121 struct sector_ptr *bio_sectors;
124 * For subpage support, we need to map each sector to above
127 struct sector_ptr *stripe_sectors;
129 /* Allocated with real_stripes-many pointers for finish_*() calls */
130 void **finish_pointers;
134 * For trace event usage only. Records useful debug info for each bio submitted
135 * by RAID56 to each physical device.
137 * No matter signed or not, (-1) is always the one indicating we can not grab
138 * the proper stripe number.
140 struct raid56_bio_trace_info {
143 /* The offset inside the stripe. (<= STRIPE_LEN) */
148 * 0 is the first data stripe, and nr_data for P stripe,
149 * nr_data + 1 for Q stripe.
150 * >= real_stripes for
155 static inline int nr_data_stripes(const struct map_lookup *map)
157 return map->num_stripes - btrfs_nr_parity_stripes(map->type);
160 #define RAID5_P_STRIPE ((u64)-2)
161 #define RAID6_Q_STRIPE ((u64)-1)
163 #define is_parity_stripe(x) (((x) == RAID5_P_STRIPE) || \
164 ((x) == RAID6_Q_STRIPE))
168 void raid56_parity_recover(struct bio *bio, struct btrfs_io_context *bioc,
169 int mirror_num, bool generic_io);
170 void raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc);
172 void raid56_add_scrub_pages(struct btrfs_raid_bio *rbio, struct page *page,
173 unsigned int pgoff, u64 logical);
175 struct btrfs_raid_bio *raid56_parity_alloc_scrub_rbio(struct bio *bio,
176 struct btrfs_io_context *bioc,
177 struct btrfs_device *scrub_dev,
178 unsigned long *dbitmap, int stripe_nsectors);
179 void raid56_parity_submit_scrub_rbio(struct btrfs_raid_bio *rbio);
181 struct btrfs_raid_bio *
182 raid56_alloc_missing_rbio(struct bio *bio, struct btrfs_io_context *bioc);
183 void raid56_submit_missing_rbio(struct btrfs_raid_bio *rbio);
185 int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info);
186 void btrfs_free_stripe_hash_table(struct btrfs_fs_info *info);