xref: /openbmc/linux/drivers/md/dm-zoned.h (revision 31e67366)
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 struct dmz_metadata;
49 struct dmz_reclaim;
50 
51 /*
52  * Zoned block device information.
53  */
54 struct dmz_dev {
55 	struct block_device	*bdev;
56 	struct dmz_metadata	*metadata;
57 	struct dmz_reclaim	*reclaim;
58 
59 	char			name[BDEVNAME_SIZE];
60 	uuid_t			uuid;
61 
62 	sector_t		capacity;
63 
64 	unsigned int		dev_idx;
65 
66 	unsigned int		nr_zones;
67 	unsigned int		zone_offset;
68 
69 	unsigned int		flags;
70 
71 	sector_t		zone_nr_sectors;
72 
73 	unsigned int		nr_rnd;
74 	atomic_t		unmap_nr_rnd;
75 	struct list_head	unmap_rnd_list;
76 	struct list_head	map_rnd_list;
77 
78 	unsigned int		nr_seq;
79 	atomic_t		unmap_nr_seq;
80 	struct list_head	unmap_seq_list;
81 	struct list_head	map_seq_list;
82 };
83 
84 #define dmz_bio_chunk(zmd, bio)	((bio)->bi_iter.bi_sector >> \
85 				 dmz_zone_nr_sectors_shift(zmd))
86 #define dmz_chunk_block(zmd, b)	((b) & (dmz_zone_nr_blocks(zmd) - 1))
87 
88 /* Device flags. */
89 #define DMZ_BDEV_DYING		(1 << 0)
90 #define DMZ_CHECK_BDEV		(2 << 0)
91 #define DMZ_BDEV_REGULAR	(4 << 0)
92 
93 /*
94  * Zone descriptor.
95  */
96 struct dm_zone {
97 	/* For listing the zone depending on its state */
98 	struct list_head	link;
99 
100 	/* Device containing this zone */
101 	struct dmz_dev		*dev;
102 
103 	/* Zone type and state */
104 	unsigned long		flags;
105 
106 	/* Zone activation reference count */
107 	atomic_t		refcount;
108 
109 	/* Zone id */
110 	unsigned int		id;
111 
112 	/* Zone write pointer block (relative to the zone start block) */
113 	unsigned int		wp_block;
114 
115 	/* Zone weight (number of valid blocks in the zone) */
116 	unsigned int		weight;
117 
118 	/* The chunk that the zone maps */
119 	unsigned int		chunk;
120 
121 	/*
122 	 * For a sequential data zone, pointer to the random zone
123 	 * used as a buffer for processing unaligned writes.
124 	 * For a buffer zone, this points back to the data zone.
125 	 */
126 	struct dm_zone		*bzone;
127 };
128 
129 /*
130  * Zone flags.
131  */
132 enum {
133 	/* Zone write type */
134 	DMZ_CACHE,
135 	DMZ_RND,
136 	DMZ_SEQ,
137 
138 	/* Zone critical condition */
139 	DMZ_OFFLINE,
140 	DMZ_READ_ONLY,
141 
142 	/* How the zone is being used */
143 	DMZ_META,
144 	DMZ_DATA,
145 	DMZ_BUF,
146 	DMZ_RESERVED,
147 
148 	/* Zone internal state */
149 	DMZ_RECLAIM,
150 	DMZ_SEQ_WRITE_ERR,
151 	DMZ_RECLAIM_TERMINATE,
152 };
153 
154 /*
155  * Zone data accessors.
156  */
157 #define dmz_is_cache(z)		test_bit(DMZ_CACHE, &(z)->flags)
158 #define dmz_is_rnd(z)		test_bit(DMZ_RND, &(z)->flags)
159 #define dmz_is_seq(z)		test_bit(DMZ_SEQ, &(z)->flags)
160 #define dmz_is_empty(z)		((z)->wp_block == 0)
161 #define dmz_is_offline(z)	test_bit(DMZ_OFFLINE, &(z)->flags)
162 #define dmz_is_readonly(z)	test_bit(DMZ_READ_ONLY, &(z)->flags)
163 #define dmz_in_reclaim(z)	test_bit(DMZ_RECLAIM, &(z)->flags)
164 #define dmz_is_reserved(z)	test_bit(DMZ_RESERVED, &(z)->flags)
165 #define dmz_seq_write_err(z)	test_bit(DMZ_SEQ_WRITE_ERR, &(z)->flags)
166 #define dmz_reclaim_should_terminate(z) \
167 				test_bit(DMZ_RECLAIM_TERMINATE, &(z)->flags)
168 
169 #define dmz_is_meta(z)		test_bit(DMZ_META, &(z)->flags)
170 #define dmz_is_buf(z)		test_bit(DMZ_BUF, &(z)->flags)
171 #define dmz_is_data(z)		test_bit(DMZ_DATA, &(z)->flags)
172 
173 #define dmz_weight(z)		((z)->weight)
174 
175 /*
176  * Message functions.
177  */
178 #define dmz_dev_info(dev, format, args...)	\
179 	DMINFO("(%s): " format, (dev)->name, ## args)
180 
181 #define dmz_dev_err(dev, format, args...)	\
182 	DMERR("(%s): " format, (dev)->name, ## args)
183 
184 #define dmz_dev_warn(dev, format, args...)	\
185 	DMWARN("(%s): " format, (dev)->name, ## args)
186 
187 #define dmz_dev_debug(dev, format, args...)	\
188 	DMDEBUG("(%s): " format, (dev)->name, ## args)
189 
190 /*
191  * Functions defined in dm-zoned-metadata.c
192  */
193 int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev,
194 		     struct dmz_metadata **zmd, const char *devname);
195 void dmz_dtr_metadata(struct dmz_metadata *zmd);
196 int dmz_resume_metadata(struct dmz_metadata *zmd);
197 
198 void dmz_lock_map(struct dmz_metadata *zmd);
199 void dmz_unlock_map(struct dmz_metadata *zmd);
200 void dmz_lock_metadata(struct dmz_metadata *zmd);
201 void dmz_unlock_metadata(struct dmz_metadata *zmd);
202 void dmz_lock_flush(struct dmz_metadata *zmd);
203 void dmz_unlock_flush(struct dmz_metadata *zmd);
204 int dmz_flush_metadata(struct dmz_metadata *zmd);
205 const char *dmz_metadata_label(struct dmz_metadata *zmd);
206 
207 sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone);
208 sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone);
209 unsigned int dmz_nr_chunks(struct dmz_metadata *zmd);
210 
211 bool dmz_check_dev(struct dmz_metadata *zmd);
212 bool dmz_dev_is_dying(struct dmz_metadata *zmd);
213 
214 #define DMZ_ALLOC_RND		0x01
215 #define DMZ_ALLOC_CACHE		0x02
216 #define DMZ_ALLOC_SEQ		0x04
217 #define DMZ_ALLOC_RECLAIM	0x10
218 
219 struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd,
220 			       unsigned int dev_idx, unsigned long flags);
221 void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
222 
223 void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *zone,
224 		  unsigned int chunk);
225 void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
226 unsigned int dmz_nr_zones(struct dmz_metadata *zmd);
227 unsigned int dmz_nr_cache_zones(struct dmz_metadata *zmd);
228 unsigned int dmz_nr_unmap_cache_zones(struct dmz_metadata *zmd);
229 unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd, int idx);
230 unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd, int idx);
231 unsigned int dmz_nr_seq_zones(struct dmz_metadata *zmd, int idx);
232 unsigned int dmz_nr_unmap_seq_zones(struct dmz_metadata *zmd, int idx);
233 unsigned int dmz_zone_nr_blocks(struct dmz_metadata *zmd);
234 unsigned int dmz_zone_nr_blocks_shift(struct dmz_metadata *zmd);
235 unsigned int dmz_zone_nr_sectors(struct dmz_metadata *zmd);
236 unsigned int dmz_zone_nr_sectors_shift(struct dmz_metadata *zmd);
237 
238 /*
239  * Activate a zone (increment its reference count).
240  */
241 static inline void dmz_activate_zone(struct dm_zone *zone)
242 {
243 	atomic_inc(&zone->refcount);
244 }
245 
246 int dmz_lock_zone_reclaim(struct dm_zone *zone);
247 void dmz_unlock_zone_reclaim(struct dm_zone *zone);
248 struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd,
249 					 unsigned int dev_idx, bool idle);
250 
251 struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd,
252 				      unsigned int chunk, int op);
253 void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *zone);
254 struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
255 				     struct dm_zone *dzone);
256 
257 int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
258 			sector_t chunk_block, unsigned int nr_blocks);
259 int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
260 			  sector_t chunk_block, unsigned int nr_blocks);
261 int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
262 		    sector_t chunk_block);
263 int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
264 			  sector_t *chunk_block);
265 int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
266 			  struct dm_zone *to_zone);
267 int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
268 			   struct dm_zone *to_zone, sector_t chunk_block);
269 
270 /*
271  * Functions defined in dm-zoned-reclaim.c
272  */
273 int dmz_ctr_reclaim(struct dmz_metadata *zmd, struct dmz_reclaim **zrc, int idx);
274 void dmz_dtr_reclaim(struct dmz_reclaim *zrc);
275 void dmz_suspend_reclaim(struct dmz_reclaim *zrc);
276 void dmz_resume_reclaim(struct dmz_reclaim *zrc);
277 void dmz_reclaim_bio_acc(struct dmz_reclaim *zrc);
278 void dmz_schedule_reclaim(struct dmz_reclaim *zrc);
279 
280 /*
281  * Functions defined in dm-zoned-target.c
282  */
283 bool dmz_bdev_is_dying(struct dmz_dev *dmz_dev);
284 bool dmz_check_bdev(struct dmz_dev *dmz_dev);
285 
286 /*
287  * Deactivate a zone. This decrement the zone reference counter
288  * indicating that all BIOs to the zone have completed when the count is 0.
289  */
290 static inline void dmz_deactivate_zone(struct dm_zone *zone)
291 {
292 	dmz_reclaim_bio_acc(zone->dev->reclaim);
293 	atomic_dec(&zone->refcount);
294 }
295 
296 /*
297  * Test if a zone is active, that is, has a refcount > 0.
298  */
299 static inline bool dmz_is_active(struct dm_zone *zone)
300 {
301 	return atomic_read(&zone->refcount);
302 }
303 
304 #endif /* DM_ZONED_H */
305