1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/vmalloc.h>
5 /* zone_size in MBs to sectors. */
6 #define ZONE_SIZE_SHIFT 11
8 static inline unsigned int null_zone_no(struct nullb_device *dev, sector_t sect)
10 return sect >> ilog2(dev->zone_size_sects);
13 int null_zone_init(struct nullb_device *dev)
15 sector_t dev_size = (sector_t)dev->size * 1024 * 1024;
19 if (!is_power_of_2(dev->zone_size)) {
20 pr_err("null_blk: zone_size must be power-of-two\n");
24 dev->zone_size_sects = dev->zone_size << ZONE_SIZE_SHIFT;
25 dev->nr_zones = dev_size >>
26 (SECTOR_SHIFT + ilog2(dev->zone_size_sects));
27 dev->zones = kvmalloc_array(dev->nr_zones, sizeof(struct blk_zone),
28 GFP_KERNEL | __GFP_ZERO);
32 if (dev->zone_nr_conv >= dev->nr_zones) {
33 dev->zone_nr_conv = dev->nr_zones - 1;
34 pr_info("null_blk: changed the number of conventional zones to %u",
38 for (i = 0; i < dev->zone_nr_conv; i++) {
39 struct blk_zone *zone = &dev->zones[i];
42 zone->len = dev->zone_size_sects;
43 zone->wp = zone->start + zone->len;
44 zone->type = BLK_ZONE_TYPE_CONVENTIONAL;
45 zone->cond = BLK_ZONE_COND_NOT_WP;
47 sector += dev->zone_size_sects;
50 for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
51 struct blk_zone *zone = &dev->zones[i];
53 zone->start = zone->wp = sector;
54 zone->len = dev->zone_size_sects;
55 zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ;
56 zone->cond = BLK_ZONE_COND_EMPTY;
58 sector += dev->zone_size_sects;
64 void null_zone_exit(struct nullb_device *dev)
69 int null_zone_report(struct gendisk *disk, sector_t sector,
70 struct blk_zone *zones, unsigned int *nr_zones,
73 struct nullb *nullb = disk->private_data;
74 struct nullb_device *dev = nullb->dev;
75 unsigned int zno, nrz = 0;
78 /* Not a zoned null device */
81 zno = null_zone_no(dev, sector);
82 if (zno < dev->nr_zones) {
83 nrz = min_t(unsigned int, *nr_zones, dev->nr_zones - zno);
84 memcpy(zones, &dev->zones[zno], nrz * sizeof(struct blk_zone));
92 void null_zone_write(struct nullb_cmd *cmd, sector_t sector,
93 unsigned int nr_sectors)
95 struct nullb_device *dev = cmd->nq->dev;
96 unsigned int zno = null_zone_no(dev, sector);
97 struct blk_zone *zone = &dev->zones[zno];
100 case BLK_ZONE_COND_FULL:
101 /* Cannot write to a full zone */
102 cmd->error = BLK_STS_IOERR;
104 case BLK_ZONE_COND_EMPTY:
105 case BLK_ZONE_COND_IMP_OPEN:
106 /* Writes must be at the write pointer position */
107 if (sector != zone->wp) {
108 cmd->error = BLK_STS_IOERR;
112 if (zone->cond == BLK_ZONE_COND_EMPTY)
113 zone->cond = BLK_ZONE_COND_IMP_OPEN;
115 zone->wp += nr_sectors;
116 if (zone->wp == zone->start + zone->len)
117 zone->cond = BLK_ZONE_COND_FULL;
119 case BLK_ZONE_COND_NOT_WP:
122 /* Invalid zone condition */
123 cmd->error = BLK_STS_IOERR;
128 void null_zone_reset(struct nullb_cmd *cmd, sector_t sector)
130 struct nullb_device *dev = cmd->nq->dev;
131 unsigned int zno = null_zone_no(dev, sector);
132 struct blk_zone *zone = &dev->zones[zno];
134 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
135 cmd->error = BLK_STS_IOERR;
139 zone->cond = BLK_ZONE_COND_EMPTY;
140 zone->wp = zone->start;