drivers/md/dm-zoned.h

   1 /*
   2  * Copyright (C) 2017 Western Digital Corporation or its affiliates.
   3  *
   4  * This file is released under the GPL.
   5  */
   6
   7 #ifndef DM_ZONED_H
   8 #define DM_ZONED_H
   9
  10 #include <linux/types.h>
  11 #include <linux/blkdev.h>
  12 #include <linux/device-mapper.h>
  13 #include <linux/dm-kcopyd.h>
  14 #include <linux/list.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/mutex.h>
  17 #include <linux/workqueue.h>
  18 #include <linux/rwsem.h>
  19 #include <linux/rbtree.h>
  20 #include <linux/radix-tree.h>
  21 #include <linux/shrinker.h>
  22
  23 /*
  24  * dm-zoned creates block devices with 4KB blocks, always.
  25  */
  26 #define DMZ_BLOCK_SHIFT         12
  27 #define DMZ_BLOCK_SIZE          (1 << DMZ_BLOCK_SHIFT)
  28 #define DMZ_BLOCK_MASK          (DMZ_BLOCK_SIZE - 1)
  29
  30 #define DMZ_BLOCK_SHIFT_BITS    (DMZ_BLOCK_SHIFT + 3)
  31 #define DMZ_BLOCK_SIZE_BITS     (1 << DMZ_BLOCK_SHIFT_BITS)
  32 #define DMZ_BLOCK_MASK_BITS     (DMZ_BLOCK_SIZE_BITS - 1)
  33
  34 #define DMZ_BLOCK_SECTORS_SHIFT (DMZ_BLOCK_SHIFT - SECTOR_SHIFT)
  35 #define DMZ_BLOCK_SECTORS       (DMZ_BLOCK_SIZE >> SECTOR_SHIFT)
  36 #define DMZ_BLOCK_SECTORS_MASK  (DMZ_BLOCK_SECTORS - 1)
  37
  38 /*
  39  * 4KB block <-> 512B sector conversion.
  40  */
  41 #define dmz_blk2sect(b)         ((sector_t)(b) << DMZ_BLOCK_SECTORS_SHIFT)
  42 #define dmz_sect2blk(s)         ((sector_t)(s) >> DMZ_BLOCK_SECTORS_SHIFT)
  43
  44 #define dmz_bio_block(bio)      dmz_sect2blk((bio)->bi_iter.bi_sector)
  45 #define dmz_bio_blocks(bio)     dmz_sect2blk(bio_sectors(bio))
  46
  47 /*
  48  * Zoned block device information.
  49  */
  50 struct dmz_dev {
  51         struct block_device     *bdev;
  52
  53         char                    name[BDEVNAME_SIZE];
  54
  55         sector_t                capacity;
  56
  57         unsigned int            nr_zones;
  58
  59         unsigned int            flags;
  60
  61         sector_t                zone_nr_sectors;
  62         unsigned int            zone_nr_sectors_shift;
  63
  64         sector_t                zone_nr_blocks;
  65         sector_t                zone_nr_blocks_shift;
  66 };
  67
  68 #define dmz_bio_chunk(dev, bio) ((bio)->bi_iter.bi_sector >> \
  69                                  (dev)->zone_nr_sectors_shift)
  70 #define dmz_chunk_block(dev, b) ((b) & ((dev)->zone_nr_blocks - 1))
  71
  72 /* Device flags. */
  73 #define DMZ_BDEV_DYING          (1 << 0)
  74 #define DMZ_CHECK_BDEV          (2 << 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 bool dmz_check_bdev(struct dmz_dev *dmz_dev);
 259
 260 #endif /* DM_ZONED_H */