1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2017 Western Digital Corporation or its affiliates.
4 *
5 * This file is released under the GPL.
6 */
7
8 #ifndef DM_ZONED_H
9 #define DM_ZONED_H
10
11 #include <linux/types.h>
12 #include <linux/blkdev.h>
13 #include <linux/device-mapper.h>
14 #include <linux/dm-kcopyd.h>
15 #include <linux/list.h>
16 #include <linux/spinlock.h>
17 #include <linux/mutex.h>
18 #include <linux/workqueue.h>
19 #include <linux/rwsem.h>
20 #include <linux/rbtree.h>
21 #include <linux/radix-tree.h>
22 #include <linux/shrinker.h>
23
24 /*
25 * dm-zoned creates block devices with 4KB blocks, always.
26 */
27 #define DMZ_BLOCK_SHIFT 12
28 #define DMZ_BLOCK_SIZE (1 << DMZ_BLOCK_SHIFT)
29 #define DMZ_BLOCK_MASK (DMZ_BLOCK_SIZE - 1)
30
31 #define DMZ_BLOCK_SHIFT_BITS (DMZ_BLOCK_SHIFT + 3)
32 #define DMZ_BLOCK_SIZE_BITS (1 << DMZ_BLOCK_SHIFT_BITS)
33 #define DMZ_BLOCK_MASK_BITS (DMZ_BLOCK_SIZE_BITS - 1)
34
35 #define DMZ_BLOCK_SECTORS_SHIFT (DMZ_BLOCK_SHIFT - SECTOR_SHIFT)
36 #define DMZ_BLOCK_SECTORS (DMZ_BLOCK_SIZE >> SECTOR_SHIFT)
37 #define DMZ_BLOCK_SECTORS_MASK (DMZ_BLOCK_SECTORS - 1)
38
39 /*
40 * 4KB block <-> 512B sector conversion.
41 */
42 #define dmz_blk2sect(b) ((sector_t)(b) << DMZ_BLOCK_SECTORS_SHIFT)
43 #define dmz_sect2blk(s) ((sector_t)(s) >> DMZ_BLOCK_SECTORS_SHIFT)
44
45 #define dmz_bio_block(bio) dmz_sect2blk((bio)->bi_iter.bi_sector)
46 #define dmz_bio_blocks(bio) dmz_sect2blk(bio_sectors(bio))
47
48 /*
49 * Zoned block device information.
50 */
51 struct dmz_dev {
52 struct block_device *bdev;
53
54 char name[BDEVNAME_SIZE];
55
56 sector_t capacity;
57
58 unsigned int nr_zones;
59
60 unsigned int flags;
61
62 sector_t zone_nr_sectors;
63 unsigned int zone_nr_sectors_shift;
64
65 sector_t zone_nr_blocks;
66 sector_t zone_nr_blocks_shift;
67 };
68
69 #define dmz_bio_chunk(dev, bio) ((bio)->bi_iter.bi_sector >> \
70 (dev)->zone_nr_sectors_shift)
71 #define dmz_chunk_block(dev, b) ((b) & ((dev)->zone_nr_blocks - 1))
72
73 /* Device flags. */
74 #define DMZ_BDEV_DYING (1 << 0)
75 #define DMZ_CHECK_BDEV (2 << 0)
76
77 /*
78 * Zone descriptor.
79 */
80 struct dm_zone {
81 /* For listing the zone depending on its state */
82 struct list_head link;
83
84 /* Zone type and state */
85 unsigned long flags;
86
87 /* Zone activation reference count */
88 atomic_t refcount;
89
90 /* Zone write pointer block (relative to the zone start block) */
91 unsigned int wp_block;
92
93 /* Zone weight (number of valid blocks in the zone) */
94 unsigned int weight;
95
96 /* The chunk that the zone maps */
97 unsigned int chunk;
98
99 /*
100 * For a sequential data zone, pointer to the random zone
101 * used as a buffer for processing unaligned writes.
102 * For a buffer zone, this points back to the data zone.
103 */
104 struct dm_zone *bzone;
105 };
106
107 /*
108 * Zone flags.
109 */
110 enum {
111 /* Zone write type */
112 DMZ_RND,
113 DMZ_SEQ,
114
115 /* Zone critical condition */
116 DMZ_OFFLINE,
117 DMZ_READ_ONLY,
118
119 /* How the zone is being used */
120 DMZ_META,
121 DMZ_DATA,
122 DMZ_BUF,
123
124 /* Zone internal state */
125 DMZ_RECLAIM,
126 DMZ_SEQ_WRITE_ERR,
127 };
128
129 /*
130 * Zone data accessors.
131 */
132 #define dmz_is_rnd(z) test_bit(DMZ_RND, &(z)->flags)
133 #define dmz_is_seq(z) test_bit(DMZ_SEQ, &(z)->flags)
134 #define dmz_is_empty(z) ((z)->wp_block == 0)
135 #define dmz_is_offline(z) test_bit(DMZ_OFFLINE, &(z)->flags)
136 #define dmz_is_readonly(z) test_bit(DMZ_READ_ONLY, &(z)->flags)
137 #define dmz_in_reclaim(z) test_bit(DMZ_RECLAIM, &(z)->flags)
138 #define dmz_seq_write_err(z) test_bit(DMZ_SEQ_WRITE_ERR, &(z)->flags)
139
140 #define dmz_is_meta(z) test_bit(DMZ_META, &(z)->flags)
141 #define dmz_is_buf(z) test_bit(DMZ_BUF, &(z)->flags)
142 #define dmz_is_data(z) test_bit(DMZ_DATA, &(z)->flags)
143
144 #define dmz_weight(z) ((z)->weight)
145
146 /*
147 * Message functions.
148 */
149 #define dmz_dev_info(dev, format, args...) \
150 DMINFO("(%s): " format, (dev)->name, ## args)
151
152 #define dmz_dev_err(dev, format, args...) \
153 DMERR("(%s): " format, (dev)->name, ## args)
154
155 #define dmz_dev_warn(dev, format, args...) \
156 DMWARN("(%s): " format, (dev)->name, ## args)
157
158 #define dmz_dev_debug(dev, format, args...) \
159 DMDEBUG("(%s): " format, (dev)->name, ## args)
160
161 struct dmz_metadata;
162 struct dmz_reclaim;
163
164 /*
165 * Functions defined in dm-zoned-metadata.c
166 */
167 int dmz_ctr_metadata(struct dmz_dev *dev, struct dmz_metadata **zmd);
168 void dmz_dtr_metadata(struct dmz_metadata *zmd);
169 int dmz_resume_metadata(struct dmz_metadata *zmd);
170
171 void dmz_lock_map(struct dmz_metadata *zmd);
172 void dmz_unlock_map(struct dmz_metadata *zmd);
173 void dmz_lock_metadata(struct dmz_metadata *zmd);
174 void dmz_unlock_metadata(struct dmz_metadata *zmd);
175 void dmz_lock_flush(struct dmz_metadata *zmd);
176 void dmz_unlock_flush(struct dmz_metadata *zmd);
177 int dmz_flush_metadata(struct dmz_metadata *zmd);
178
179 unsigned int dmz_id(struct dmz_metadata *zmd, struct dm_zone *zone);
180 sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone);
181 sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone);
182 unsigned int dmz_nr_chunks(struct dmz_metadata *zmd);
183
184 #define DMZ_ALLOC_RND 0x01
185 #define DMZ_ALLOC_RECLAIM 0x02
186
187 struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned long flags);
188 void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
189
190 void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *zone,
191 unsigned int chunk);
192 void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
193 unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd);
194 unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd);
195
196 /*
197 * Activate a zone (increment its reference count).
198 */
dmz_activate_zone(struct dm_zone * zone)199 static inline void dmz_activate_zone(struct dm_zone *zone)
200 {
201 atomic_inc(&zone->refcount);
202 }
203
204 /*
205 * Deactivate a zone. This decrement the zone reference counter
206 * indicating that all BIOs to the zone have completed when the count is 0.
207 */
dmz_deactivate_zone(struct dm_zone * zone)208 static inline void dmz_deactivate_zone(struct dm_zone *zone)
209 {
210 atomic_dec(&zone->refcount);
211 }
212
213 /*
214 * Test if a zone is active, that is, has a refcount > 0.
215 */
dmz_is_active(struct dm_zone * zone)216 static inline bool dmz_is_active(struct dm_zone *zone)
217 {
218 return atomic_read(&zone->refcount);
219 }
220
221 int dmz_lock_zone_reclaim(struct dm_zone *zone);
222 void dmz_unlock_zone_reclaim(struct dm_zone *zone);
223 struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd);
224
225 struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd,
226 unsigned int chunk, int op);
227 void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *zone);
228 struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
229 struct dm_zone *dzone);
230
231 int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
232 sector_t chunk_block, unsigned int nr_blocks);
233 int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
234 sector_t chunk_block, unsigned int nr_blocks);
235 int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
236 sector_t chunk_block);
237 int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
238 sector_t *chunk_block);
239 int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
240 struct dm_zone *to_zone);
241 int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
242 struct dm_zone *to_zone, sector_t chunk_block);
243
244 /*
245 * Functions defined in dm-zoned-reclaim.c
246 */
247 int dmz_ctr_reclaim(struct dmz_dev *dev, struct dmz_metadata *zmd,
248 struct dmz_reclaim **zrc);
249 void dmz_dtr_reclaim(struct dmz_reclaim *zrc);
250 void dmz_suspend_reclaim(struct dmz_reclaim *zrc);
251 void dmz_resume_reclaim(struct dmz_reclaim *zrc);
252 void dmz_reclaim_bio_acc(struct dmz_reclaim *zrc);
253 void dmz_schedule_reclaim(struct dmz_reclaim *zrc);
254
255 /*
256 * Functions defined in dm-zoned-target.c
257 */
258 bool dmz_bdev_is_dying(struct dmz_dev *dmz_dev);
259 bool dmz_check_bdev(struct dmz_dev *dmz_dev);
260
261 #endif /* DM_ZONED_H */
262