mirror of https://gitee.com/openkylin/linux.git
144 lines
3.4 KiB
C
144 lines
3.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/vmalloc.h>
|
|
#include "null_blk.h"
|
|
|
|
/* zone_size in MBs to sectors. */
|
|
#define ZONE_SIZE_SHIFT 11
|
|
|
|
static inline unsigned int null_zone_no(struct nullb_device *dev, sector_t sect)
|
|
{
|
|
return sect >> ilog2(dev->zone_size_sects);
|
|
}
|
|
|
|
int null_zone_init(struct nullb_device *dev)
|
|
{
|
|
sector_t dev_size = (sector_t)dev->size * 1024 * 1024;
|
|
sector_t sector = 0;
|
|
unsigned int i;
|
|
|
|
if (!is_power_of_2(dev->zone_size)) {
|
|
pr_err("null_blk: zone_size must be power-of-two\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
dev->zone_size_sects = dev->zone_size << ZONE_SIZE_SHIFT;
|
|
dev->nr_zones = dev_size >>
|
|
(SECTOR_SHIFT + ilog2(dev->zone_size_sects));
|
|
dev->zones = kvmalloc_array(dev->nr_zones, sizeof(struct blk_zone),
|
|
GFP_KERNEL | __GFP_ZERO);
|
|
if (!dev->zones)
|
|
return -ENOMEM;
|
|
|
|
for (i = 0; i < dev->nr_zones; i++) {
|
|
struct blk_zone *zone = &dev->zones[i];
|
|
|
|
zone->start = zone->wp = sector;
|
|
zone->len = dev->zone_size_sects;
|
|
zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ;
|
|
zone->cond = BLK_ZONE_COND_EMPTY;
|
|
|
|
sector += dev->zone_size_sects;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void null_zone_exit(struct nullb_device *dev)
|
|
{
|
|
kvfree(dev->zones);
|
|
}
|
|
|
|
static void null_zone_fill_bio(struct nullb_device *dev, struct bio *bio,
|
|
unsigned int zno, unsigned int nr_zones)
|
|
{
|
|
struct blk_zone_report_hdr *hdr = NULL;
|
|
struct bio_vec bvec;
|
|
struct bvec_iter iter;
|
|
void *addr;
|
|
unsigned int zones_to_cpy;
|
|
|
|
bio_for_each_segment(bvec, bio, iter) {
|
|
addr = kmap_atomic(bvec.bv_page);
|
|
|
|
zones_to_cpy = bvec.bv_len / sizeof(struct blk_zone);
|
|
|
|
if (!hdr) {
|
|
hdr = (struct blk_zone_report_hdr *)addr;
|
|
hdr->nr_zones = nr_zones;
|
|
zones_to_cpy--;
|
|
addr += sizeof(struct blk_zone_report_hdr);
|
|
}
|
|
|
|
zones_to_cpy = min_t(unsigned int, zones_to_cpy, nr_zones);
|
|
|
|
memcpy(addr, &dev->zones[zno],
|
|
zones_to_cpy * sizeof(struct blk_zone));
|
|
|
|
kunmap_atomic(addr);
|
|
|
|
nr_zones -= zones_to_cpy;
|
|
zno += zones_to_cpy;
|
|
|
|
if (!nr_zones)
|
|
break;
|
|
}
|
|
}
|
|
|
|
blk_status_t null_zone_report(struct nullb *nullb, struct bio *bio)
|
|
{
|
|
struct nullb_device *dev = nullb->dev;
|
|
unsigned int zno = null_zone_no(dev, bio->bi_iter.bi_sector);
|
|
unsigned int nr_zones = dev->nr_zones - zno;
|
|
unsigned int max_zones;
|
|
|
|
max_zones = (bio->bi_iter.bi_size / sizeof(struct blk_zone)) - 1;
|
|
nr_zones = min_t(unsigned int, nr_zones, max_zones);
|
|
null_zone_fill_bio(nullb->dev, bio, zno, nr_zones);
|
|
|
|
return BLK_STS_OK;
|
|
}
|
|
|
|
void null_zone_write(struct nullb_cmd *cmd, sector_t sector,
|
|
unsigned int nr_sectors)
|
|
{
|
|
struct nullb_device *dev = cmd->nq->dev;
|
|
unsigned int zno = null_zone_no(dev, sector);
|
|
struct blk_zone *zone = &dev->zones[zno];
|
|
|
|
switch (zone->cond) {
|
|
case BLK_ZONE_COND_FULL:
|
|
/* Cannot write to a full zone */
|
|
cmd->error = BLK_STS_IOERR;
|
|
break;
|
|
case BLK_ZONE_COND_EMPTY:
|
|
case BLK_ZONE_COND_IMP_OPEN:
|
|
/* Writes must be at the write pointer position */
|
|
if (sector != zone->wp) {
|
|
cmd->error = BLK_STS_IOERR;
|
|
break;
|
|
}
|
|
|
|
if (zone->cond == BLK_ZONE_COND_EMPTY)
|
|
zone->cond = BLK_ZONE_COND_IMP_OPEN;
|
|
|
|
zone->wp += nr_sectors;
|
|
if (zone->wp == zone->start + zone->len)
|
|
zone->cond = BLK_ZONE_COND_FULL;
|
|
break;
|
|
default:
|
|
/* Invalid zone condition */
|
|
cmd->error = BLK_STS_IOERR;
|
|
break;
|
|
}
|
|
}
|
|
|
|
void null_zone_reset(struct nullb_cmd *cmd, sector_t sector)
|
|
{
|
|
struct nullb_device *dev = cmd->nq->dev;
|
|
unsigned int zno = null_zone_no(dev, sector);
|
|
struct blk_zone *zone = &dev->zones[zno];
|
|
|
|
zone->cond = BLK_ZONE_COND_EMPTY;
|
|
zone->wp = zone->start;
|
|
}
|