xref: /linux/drivers/md/dm-zoned.h (revision 7505576d1c1ac0cfe85fdf90999433dd8b673012)
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 
76 /*
77  * Zone descriptor.
78  */
79 struct dm_zone {
80 	/* For listing the zone depending on its state */
81 	struct list_head	link;
82 
83 	/* Zone type and state */
84 	unsigned long		flags;
85 
86 	/* Zone activation reference count */
87 	atomic_t		refcount;
88 
89 	/* Zone write pointer block (relative to the zone start block) */
90 	unsigned int		wp_block;
91 
92 	/* Zone weight (number of valid blocks in the zone) */
93 	unsigned int		weight;
94 
95 	/* The chunk that the zone maps */
96 	unsigned int		chunk;
97 
98 	/*
99 	 * For a sequential data zone, pointer to the random zone
100 	 * used as a buffer for processing unaligned writes.
101 	 * For a buffer zone, this points back to the data zone.
102 	 */
103 	struct dm_zone		*bzone;
104 };
105 
106 /*
107  * Zone flags.
108  */
109 enum {
110 	/* Zone write type */
111 	DMZ_RND,
112 	DMZ_SEQ,
113 
114 	/* Zone critical condition */
115 	DMZ_OFFLINE,
116 	DMZ_READ_ONLY,
117 
118 	/* How the zone is being used */
119 	DMZ_META,
120 	DMZ_DATA,
121 	DMZ_BUF,
122 
123 	/* Zone internal state */
124 	DMZ_RECLAIM,
125 	DMZ_SEQ_WRITE_ERR,
126 };
127 
128 /*
129  * Zone data accessors.
130  */
131 #define dmz_is_rnd(z)		test_bit(DMZ_RND, &(z)->flags)
132 #define dmz_is_seq(z)		test_bit(DMZ_SEQ, &(z)->flags)
133 #define dmz_is_empty(z)		((z)->wp_block == 0)
134 #define dmz_is_offline(z)	test_bit(DMZ_OFFLINE, &(z)->flags)
135 #define dmz_is_readonly(z)	test_bit(DMZ_READ_ONLY, &(z)->flags)
136 #define dmz_in_reclaim(z)	test_bit(DMZ_RECLAIM, &(z)->flags)
137 #define dmz_seq_write_err(z)	test_bit(DMZ_SEQ_WRITE_ERR, &(z)->flags)
138 
139 #define dmz_is_meta(z)		test_bit(DMZ_META, &(z)->flags)
140 #define dmz_is_buf(z)		test_bit(DMZ_BUF, &(z)->flags)
141 #define dmz_is_data(z)		test_bit(DMZ_DATA, &(z)->flags)
142 
143 #define dmz_weight(z)		((z)->weight)
144 
145 /*
146  * Message functions.
147  */
148 #define dmz_dev_info(dev, format, args...)	\
149 	DMINFO("(%s): " format, (dev)->name, ## args)
150 
151 #define dmz_dev_err(dev, format, args...)	\
152 	DMERR("(%s): " format, (dev)->name, ## args)
153 
154 #define dmz_dev_warn(dev, format, args...)	\
155 	DMWARN("(%s): " format, (dev)->name, ## args)
156 
157 #define dmz_dev_debug(dev, format, args...)	\
158 	DMDEBUG("(%s): " format, (dev)->name, ## args)
159 
160 struct dmz_metadata;
161 struct dmz_reclaim;
162 
163 /*
164  * Functions defined in dm-zoned-metadata.c
165  */
166 int dmz_ctr_metadata(struct dmz_dev *dev, struct dmz_metadata **zmd);
167 void dmz_dtr_metadata(struct dmz_metadata *zmd);
168 int dmz_resume_metadata(struct dmz_metadata *zmd);
169 
170 void dmz_lock_map(struct dmz_metadata *zmd);
171 void dmz_unlock_map(struct dmz_metadata *zmd);
172 void dmz_lock_metadata(struct dmz_metadata *zmd);
173 void dmz_unlock_metadata(struct dmz_metadata *zmd);
174 void dmz_lock_flush(struct dmz_metadata *zmd);
175 void dmz_unlock_flush(struct dmz_metadata *zmd);
176 int dmz_flush_metadata(struct dmz_metadata *zmd);
177 
178 unsigned int dmz_id(struct dmz_metadata *zmd, struct dm_zone *zone);
179 sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone);
180 sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone);
181 unsigned int dmz_nr_chunks(struct dmz_metadata *zmd);
182 
183 #define DMZ_ALLOC_RND		0x01
184 #define DMZ_ALLOC_RECLAIM	0x02
185 
186 struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned long flags);
187 void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
188 
189 void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *zone,
190 		  unsigned int chunk);
191 void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
192 unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd);
193 unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd);
194 
195 /*
196  * Activate a zone (increment its reference count).
197  */
198 static inline void dmz_activate_zone(struct dm_zone *zone)
199 {
200 	atomic_inc(&zone->refcount);
201 }
202 
203 /*
204  * Deactivate a zone. This decrement the zone reference counter
205  * indicating that all BIOs to the zone have completed when the count is 0.
206  */
207 static inline void dmz_deactivate_zone(struct dm_zone *zone)
208 {
209 	atomic_dec(&zone->refcount);
210 }
211 
212 /*
213  * Test if a zone is active, that is, has a refcount > 0.
214  */
215 static inline bool dmz_is_active(struct dm_zone *zone)
216 {
217 	return atomic_read(&zone->refcount);
218 }
219 
220 int dmz_lock_zone_reclaim(struct dm_zone *zone);
221 void dmz_unlock_zone_reclaim(struct dm_zone *zone);
222 struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd);
223 
224 struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd,
225 				      unsigned int chunk, int op);
226 void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *zone);
227 struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
228 				     struct dm_zone *dzone);
229 
230 int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
231 			sector_t chunk_block, unsigned int nr_blocks);
232 int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
233 			  sector_t chunk_block, unsigned int nr_blocks);
234 int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
235 		    sector_t chunk_block);
236 int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
237 			  sector_t *chunk_block);
238 int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
239 			  struct dm_zone *to_zone);
240 int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
241 			   struct dm_zone *to_zone, sector_t chunk_block);
242 
243 /*
244  * Functions defined in dm-zoned-reclaim.c
245  */
246 int dmz_ctr_reclaim(struct dmz_dev *dev, struct dmz_metadata *zmd,
247 		    struct dmz_reclaim **zrc);
248 void dmz_dtr_reclaim(struct dmz_reclaim *zrc);
249 void dmz_suspend_reclaim(struct dmz_reclaim *zrc);
250 void dmz_resume_reclaim(struct dmz_reclaim *zrc);
251 void dmz_reclaim_bio_acc(struct dmz_reclaim *zrc);
252 void dmz_schedule_reclaim(struct dmz_reclaim *zrc);
253 
254 /*
255  * Functions defined in dm-zoned-target.c
256  */
257 bool dmz_bdev_is_dying(struct dmz_dev *dmz_dev);
258 
259 #endif /* DM_ZONED_H */
260