drivers/block/null_blk_zoned.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/vmalloc.h>
   3 #include "null_blk.h"
   4
   5 #define CREATE_TRACE_POINTS
   6 #include "null_blk_trace.h"
   7
   8 /* zone_size in MBs to sectors. */
   9 #define ZONE_SIZE_SHIFT         11
  10
  11 static inline unsigned int null_zone_no(struct nullb_device *dev, sector_t sect)
  12 {
  13         return sect >> ilog2(dev->zone_size_sects);
  14 }
  15
  16 int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q)
  17 {
  18         sector_t dev_size = (sector_t)dev->size * 1024 * 1024;
  19         sector_t sector = 0;
  20         unsigned int i;
  21
  22         if (!is_power_of_2(dev->zone_size)) {
  23                 pr_err("zone_size must be power-of-two\n");
  24                 return -EINVAL;
  25         }
  26         if (dev->zone_size > dev->size) {
  27                 pr_err("Zone size larger than device capacity\n");
  28                 return -EINVAL;
  29         }
  30
  31         if (!dev->zone_capacity)
  32                 dev->zone_capacity = dev->zone_size;
  33
  34         if (dev->zone_capacity > dev->zone_size) {
  35                 pr_err("null_blk: zone capacity (%lu MB) larger than zone size (%lu MB)\n",
  36                                         dev->zone_capacity, dev->zone_size);
  37                 return -EINVAL;
  38         }
  39
  40         dev->zone_size_sects = dev->zone_size << ZONE_SIZE_SHIFT;
  41         dev->nr_zones = dev_size >>
  42                                 (SECTOR_SHIFT + ilog2(dev->zone_size_sects));
  43         dev->zones = kvmalloc_array(dev->nr_zones, sizeof(struct blk_zone),
  44                         GFP_KERNEL | __GFP_ZERO);
  45         if (!dev->zones)
  46                 return -ENOMEM;
  47
  48         if (dev->zone_nr_conv >= dev->nr_zones) {
  49                 dev->zone_nr_conv = dev->nr_zones - 1;
  50                 pr_info("changed the number of conventional zones to %u",
  51                         dev->zone_nr_conv);
  52         }
  53
  54         for (i = 0; i <  dev->zone_nr_conv; i++) {
  55                 struct blk_zone *zone = &dev->zones[i];
  56
  57                 zone->start = sector;
  58                 zone->len = dev->zone_size_sects;
  59                 zone->capacity = zone->len;
  60                 zone->wp = zone->start + zone->len;
  61                 zone->type = BLK_ZONE_TYPE_CONVENTIONAL;
  62                 zone->cond = BLK_ZONE_COND_NOT_WP;
  63
  64                 sector += dev->zone_size_sects;
  65         }
  66
  67         for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
  68                 struct blk_zone *zone = &dev->zones[i];
  69
  70                 zone->start = zone->wp = sector;
  71                 zone->len = dev->zone_size_sects;
  72                 zone->capacity = dev->zone_capacity << ZONE_SIZE_SHIFT;
  73                 zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ;
  74                 zone->cond = BLK_ZONE_COND_EMPTY;
  75
  76                 sector += dev->zone_size_sects;
  77         }
  78
  79         q->limits.zoned = BLK_ZONED_HM;
  80         blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
  81         blk_queue_required_elevator_features(q, ELEVATOR_F_ZBD_SEQ_WRITE);
  82
  83         return 0;
  84 }
  85
  86 int null_register_zoned_dev(struct nullb *nullb)
  87 {
  88         struct nullb_device *dev = nullb->dev;
  89         struct request_queue *q = nullb->q;
  90
  91         if (queue_is_mq(q)) {
  92                 int ret = blk_revalidate_disk_zones(nullb->disk, NULL);
  93
  94                 if (ret)
  95                         return ret;
  96         } else {
  97                 blk_queue_chunk_sectors(q, dev->zone_size_sects);
  98                 q->nr_zones = blkdev_nr_zones(nullb->disk);
  99         }
 100
 101         blk_queue_max_zone_append_sectors(q, dev->zone_size_sects);
 102
 103         return 0;
 104 }
 105
 106 void null_free_zoned_dev(struct nullb_device *dev)
 107 {
 108         kvfree(dev->zones);
 109 }
 110
 111 int null_report_zones(struct gendisk *disk, sector_t sector,
 112                 unsigned int nr_zones, report_zones_cb cb, void *data)
 113 {
 114         struct nullb *nullb = disk->private_data;
 115         struct nullb_device *dev = nullb->dev;
 116         unsigned int first_zone, i;
 117         struct blk_zone zone;
 118         int error;
 119
 120         first_zone = null_zone_no(dev, sector);
 121         if (first_zone >= dev->nr_zones)
 122                 return 0;
 123
 124         nr_zones = min(nr_zones, dev->nr_zones - first_zone);
 125         trace_nullb_report_zones(nullb, nr_zones);
 126
 127         for (i = 0; i < nr_zones; i++) {
 128                 /*
 129                  * Stacked DM target drivers will remap the zone information by
 130                  * modifying the zone information passed to the report callback.
 131                  * So use a local copy to avoid corruption of the device zone
 132                  * array.
 133                  */
 134                 memcpy(&zone, &dev->zones[first_zone + i],
 135                        sizeof(struct blk_zone));
 136                 error = cb(&zone, i, data);
 137                 if (error)
 138                         return error;
 139         }
 140
 141         return nr_zones;
 142 }
 143
 144 size_t null_zone_valid_read_len(struct nullb *nullb,
 145                                 sector_t sector, unsigned int len)
 146 {
 147         struct nullb_device *dev = nullb->dev;
 148         struct blk_zone *zone = &dev->zones[null_zone_no(dev, sector)];
 149         unsigned int nr_sectors = len >> SECTOR_SHIFT;
 150
 151         /* Read must be below the write pointer position */
 152         if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL ||
 153             sector + nr_sectors <= zone->wp)
 154                 return len;
 155
 156         if (sector > zone->wp)
 157                 return 0;
 158
 159         return (zone->wp - sector) << SECTOR_SHIFT;
 160 }
 161
 162 static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector,
 163                                     unsigned int nr_sectors, bool append)
 164 {
 165         struct nullb_device *dev = cmd->nq->dev;
 166         unsigned int zno = null_zone_no(dev, sector);
 167         struct blk_zone *zone = &dev->zones[zno];
 168         blk_status_t ret;
 169
 170         trace_nullb_zone_op(cmd, zno, zone->cond);
 171
 172         if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 173                 return null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
 174
 175         switch (zone->cond) {
 176         case BLK_ZONE_COND_FULL:
 177                 /* Cannot write to a full zone */
 178                 return BLK_STS_IOERR;
 179         case BLK_ZONE_COND_EMPTY:
 180         case BLK_ZONE_COND_IMP_OPEN:
 181         case BLK_ZONE_COND_EXP_OPEN:
 182         case BLK_ZONE_COND_CLOSED:
 183                 /*
 184                  * Regular writes must be at the write pointer position.
 185                  * Zone append writes are automatically issued at the write
 186                  * pointer and the position returned using the request or BIO
 187                  * sector.
 188                  */
 189                 if (append) {
 190                         sector = zone->wp;
 191                         if (cmd->bio)
 192                                 cmd->bio->bi_iter.bi_sector = sector;
 193                         else
 194                                 cmd->rq->__sector = sector;
 195                 } else if (sector != zone->wp) {
 196                         return BLK_STS_IOERR;
 197                 }
 198
 199                 if (zone->wp + nr_sectors > zone->start + zone->capacity)
 200                         return BLK_STS_IOERR;
 201
 202                 if (zone->cond != BLK_ZONE_COND_EXP_OPEN)
 203                         zone->cond = BLK_ZONE_COND_IMP_OPEN;
 204
 205                 ret = null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
 206                 if (ret != BLK_STS_OK)
 207                         return ret;
 208
 209                 zone->wp += nr_sectors;
 210                 if (zone->wp == zone->start + zone->capacity)
 211                         zone->cond = BLK_ZONE_COND_FULL;
 212                 return BLK_STS_OK;
 213         default:
 214                 /* Invalid zone condition */
 215                 return BLK_STS_IOERR;
 216         }
 217 }
 218
 219 static blk_status_t null_zone_mgmt(struct nullb_cmd *cmd, enum req_opf op,
 220                                    sector_t sector)
 221 {
 222         struct nullb_device *dev = cmd->nq->dev;
 223         unsigned int zone_no = null_zone_no(dev, sector);
 224         struct blk_zone *zone = &dev->zones[zone_no];
 225         size_t i;
 226
 227         switch (op) {
 228         case REQ_OP_ZONE_RESET_ALL:
 229                 for (i = 0; i < dev->nr_zones; i++) {
 230                         if (zone[i].type == BLK_ZONE_TYPE_CONVENTIONAL)
 231                                 continue;
 232                         zone[i].cond = BLK_ZONE_COND_EMPTY;
 233                         zone[i].wp = zone[i].start;
 234                 }
 235                 break;
 236         case REQ_OP_ZONE_RESET:
 237                 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 238                         return BLK_STS_IOERR;
 239
 240                 zone->cond = BLK_ZONE_COND_EMPTY;
 241                 zone->wp = zone->start;
 242                 break;
 243         case REQ_OP_ZONE_OPEN:
 244                 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 245                         return BLK_STS_IOERR;
 246                 if (zone->cond == BLK_ZONE_COND_FULL)
 247                         return BLK_STS_IOERR;
 248
 249                 zone->cond = BLK_ZONE_COND_EXP_OPEN;
 250                 break;
 251         case REQ_OP_ZONE_CLOSE:
 252                 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 253                         return BLK_STS_IOERR;
 254                 if (zone->cond == BLK_ZONE_COND_FULL)
 255                         return BLK_STS_IOERR;
 256
 257                 if (zone->wp == zone->start)
 258                         zone->cond = BLK_ZONE_COND_EMPTY;
 259                 else
 260                         zone->cond = BLK_ZONE_COND_CLOSED;
 261                 break;
 262         case REQ_OP_ZONE_FINISH:
 263                 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 264                         return BLK_STS_IOERR;
 265
 266                 zone->cond = BLK_ZONE_COND_FULL;
 267                 zone->wp = zone->start + zone->len;
 268                 break;
 269         default:
 270                 return BLK_STS_NOTSUPP;
 271         }
 272
 273         trace_nullb_zone_op(cmd, zone_no, zone->cond);
 274         return BLK_STS_OK;
 275 }
 276
 277 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_opf op,
 278                                     sector_t sector, sector_t nr_sectors)
 279 {
 280         switch (op) {
 281         case REQ_OP_WRITE:
 282                 return null_zone_write(cmd, sector, nr_sectors, false);
 283         case REQ_OP_ZONE_APPEND:
 284                 return null_zone_write(cmd, sector, nr_sectors, true);
 285         case REQ_OP_ZONE_RESET:
 286         case REQ_OP_ZONE_RESET_ALL:
 287         case REQ_OP_ZONE_OPEN:
 288         case REQ_OP_ZONE_CLOSE:
 289         case REQ_OP_ZONE_FINISH:
 290                 return null_zone_mgmt(cmd, op, sector);
 291         default:
 292                 return null_process_cmd(cmd, op, sector, nr_sectors);
 293         }
 294 }