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
  27         dev->zone_size_sects = dev->zone_size << ZONE_SIZE_SHIFT;
  28         dev->nr_zones = dev_size >>
  29                                 (SECTOR_SHIFT + ilog2(dev->zone_size_sects));
  30         dev->zones = kvmalloc_array(dev->nr_zones, sizeof(struct blk_zone),
  31                         GFP_KERNEL | __GFP_ZERO);
  32         if (!dev->zones)
  33                 return -ENOMEM;
  34
  35         if (dev->zone_nr_conv >= dev->nr_zones) {
  36                 dev->zone_nr_conv = dev->nr_zones - 1;
  37                 pr_info("changed the number of conventional zones to %u",
  38                         dev->zone_nr_conv);
  39         }
  40
  41         for (i = 0; i <  dev->zone_nr_conv; i++) {
  42                 struct blk_zone *zone = &dev->zones[i];
  43
  44                 zone->start = sector;
  45                 zone->len = dev->zone_size_sects;
  46                 zone->wp = zone->start + zone->len;
  47                 zone->type = BLK_ZONE_TYPE_CONVENTIONAL;
  48                 zone->cond = BLK_ZONE_COND_NOT_WP;
  49
  50                 sector += dev->zone_size_sects;
  51         }
  52
  53         for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
  54                 struct blk_zone *zone = &dev->zones[i];
  55
  56                 zone->start = zone->wp = sector;
  57                 zone->len = dev->zone_size_sects;
  58                 zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ;
  59                 zone->cond = BLK_ZONE_COND_EMPTY;
  60
  61                 sector += dev->zone_size_sects;
  62         }
  63
  64         q->limits.zoned = BLK_ZONED_HM;
  65         blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
  66         blk_queue_required_elevator_features(q, ELEVATOR_F_ZBD_SEQ_WRITE);
  67
  68         return 0;
  69 }
  70
  71 int null_register_zoned_dev(struct nullb *nullb)
  72 {
  73         struct request_queue *q = nullb->q;
  74
  75         if (queue_is_mq(q))
  76                 return blk_revalidate_disk_zones(nullb->disk, NULL);
  77
  78         blk_queue_chunk_sectors(q, nullb->dev->zone_size_sects);
  79         q->nr_zones = blkdev_nr_zones(nullb->disk);
  80
  81         return 0;
  82 }
  83
  84 void null_free_zoned_dev(struct nullb_device *dev)
  85 {
  86         kvfree(dev->zones);
  87 }
  88
  89 int null_report_zones(struct gendisk *disk, sector_t sector,
  90                 unsigned int nr_zones, report_zones_cb cb, void *data)
  91 {
  92         struct nullb *nullb = disk->private_data;
  93         struct nullb_device *dev = nullb->dev;
  94         unsigned int first_zone, i;
  95         struct blk_zone zone;
  96         int error;
  97
  98         first_zone = null_zone_no(dev, sector);
  99         if (first_zone >= dev->nr_zones)
 100                 return 0;
 101
 102         nr_zones = min(nr_zones, dev->nr_zones - first_zone);
 103         trace_nullb_report_zones(nullb, nr_zones);
 104
 105         for (i = 0; i < nr_zones; i++) {
 106                 /*
 107                  * Stacked DM target drivers will remap the zone information by
 108                  * modifying the zone information passed to the report callback.
 109                  * So use a local copy to avoid corruption of the device zone
 110                  * array.
 111                  */
 112                 memcpy(&zone, &dev->zones[first_zone + i],
 113                        sizeof(struct blk_zone));
 114                 error = cb(&zone, i, data);
 115                 if (error)
 116                         return error;
 117         }
 118
 119         return nr_zones;
 120 }
 121
 122 size_t null_zone_valid_read_len(struct nullb *nullb,
 123                                 sector_t sector, unsigned int len)
 124 {
 125         struct nullb_device *dev = nullb->dev;
 126         struct blk_zone *zone = &dev->zones[null_zone_no(dev, sector)];
 127         unsigned int nr_sectors = len >> SECTOR_SHIFT;
 128
 129         /* Read must be below the write pointer position */
 130         if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL ||
 131             sector + nr_sectors <= zone->wp)
 132                 return len;
 133
 134         if (sector > zone->wp)
 135                 return 0;
 136
 137         return (zone->wp - sector) << SECTOR_SHIFT;
 138 }
 139
 140 static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector,
 141                      unsigned int nr_sectors)
 142 {
 143         struct nullb_device *dev = cmd->nq->dev;
 144         unsigned int zno = null_zone_no(dev, sector);
 145         struct blk_zone *zone = &dev->zones[zno];
 146         blk_status_t ret;
 147
 148         trace_nullb_zone_op(cmd, zno, zone->cond);
 149
 150         if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 151                 return null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
 152
 153         switch (zone->cond) {
 154         case BLK_ZONE_COND_FULL:
 155                 /* Cannot write to a full zone */
 156                 return BLK_STS_IOERR;
 157         case BLK_ZONE_COND_EMPTY:
 158         case BLK_ZONE_COND_IMP_OPEN:
 159         case BLK_ZONE_COND_EXP_OPEN:
 160         case BLK_ZONE_COND_CLOSED:
 161                 /* Writes must be at the write pointer position */
 162                 if (sector != zone->wp)
 163                         return BLK_STS_IOERR;
 164
 165                 if (zone->cond != BLK_ZONE_COND_EXP_OPEN)
 166                         zone->cond = BLK_ZONE_COND_IMP_OPEN;
 167
 168                 ret = null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
 169                 if (ret != BLK_STS_OK)
 170                         return ret;
 171
 172                 zone->wp += nr_sectors;
 173                 if (zone->wp == zone->start + zone->len)
 174                         zone->cond = BLK_ZONE_COND_FULL;
 175                 return BLK_STS_OK;
 176         default:
 177                 /* Invalid zone condition */
 178                 return BLK_STS_IOERR;
 179         }
 180 }
 181
 182 static blk_status_t null_zone_mgmt(struct nullb_cmd *cmd, enum req_opf op,
 183                                    sector_t sector)
 184 {
 185         struct nullb_device *dev = cmd->nq->dev;
 186         unsigned int zone_no = null_zone_no(dev, sector);
 187         struct blk_zone *zone = &dev->zones[zone_no];
 188         size_t i;
 189
 190         switch (op) {
 191         case REQ_OP_ZONE_RESET_ALL:
 192                 for (i = 0; i < dev->nr_zones; i++) {
 193                         if (zone[i].type == BLK_ZONE_TYPE_CONVENTIONAL)
 194                                 continue;
 195                         zone[i].cond = BLK_ZONE_COND_EMPTY;
 196                         zone[i].wp = zone[i].start;
 197                 }
 198                 break;
 199         case REQ_OP_ZONE_RESET:
 200                 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 201                         return BLK_STS_IOERR;
 202
 203                 zone->cond = BLK_ZONE_COND_EMPTY;
 204                 zone->wp = zone->start;
 205                 break;
 206         case REQ_OP_ZONE_OPEN:
 207                 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 208                         return BLK_STS_IOERR;
 209                 if (zone->cond == BLK_ZONE_COND_FULL)
 210                         return BLK_STS_IOERR;
 211
 212                 zone->cond = BLK_ZONE_COND_EXP_OPEN;
 213                 break;
 214         case REQ_OP_ZONE_CLOSE:
 215                 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 216                         return BLK_STS_IOERR;
 217                 if (zone->cond == BLK_ZONE_COND_FULL)
 218                         return BLK_STS_IOERR;
 219
 220                 if (zone->wp == zone->start)
 221                         zone->cond = BLK_ZONE_COND_EMPTY;
 222                 else
 223                         zone->cond = BLK_ZONE_COND_CLOSED;
 224                 break;
 225         case REQ_OP_ZONE_FINISH:
 226                 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 227                         return BLK_STS_IOERR;
 228
 229                 zone->cond = BLK_ZONE_COND_FULL;
 230                 zone->wp = zone->start + zone->len;
 231                 break;
 232         default:
 233                 return BLK_STS_NOTSUPP;
 234         }
 235
 236         trace_nullb_zone_op(cmd, zone_no, zone->cond);
 237         return BLK_STS_OK;
 238 }
 239
 240 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_opf op,
 241                                     sector_t sector, sector_t nr_sectors)
 242 {
 243         switch (op) {
 244         case REQ_OP_WRITE:
 245                 return null_zone_write(cmd, sector, nr_sectors);
 246         case REQ_OP_ZONE_RESET:
 247         case REQ_OP_ZONE_RESET_ALL:
 248         case REQ_OP_ZONE_OPEN:
 249         case REQ_OP_ZONE_CLOSE:
 250         case REQ_OP_ZONE_FINISH:
 251                 return null_zone_mgmt(cmd, op, sector);
 252         default:
 253                 return null_process_cmd(cmd, op, sector, nr_sectors);
 254         }
 255 }