block: add a report_zones method

Dispatching a report zones command through the request queue is a major
pain due to the command reply payload rewriting necessary. Given that
blkdev_report_zones() is executing everything synchronously, implement
report zones as a block device file operation instead, allowing major
simplification of the code in many places.

sd, null-blk, dm-linear and dm-flakey being the only block device
drivers supporting exposing zoned block devices, these drivers are
modified to provide the device side implementation of the
report_zones() block device file operation.

For device mappers, a new report_zones() target type operation is
defined so that the upper block layer calls blkdev_report_zones() can
be propagated down to the underlying devices of the dm targets.
Implementation for this new operation is added to the dm-linear and
dm-flakey targets.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[Damien]
* Changed method block_device argument to gendisk
* Various bug fixes and improvements
* Added support for null_blk, dm-linear and dm-flakey.
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig
2018-10-12 19:08:49 +09:00
committed by Jens Axboe
parent 965b652e90
commit e76239a374
16 changed files with 270 additions and 429 deletions

View File

@@ -102,19 +102,6 @@ static int linear_map(struct dm_target *ti, struct bio *bio)
return DM_MAPIO_REMAPPED;
}
#ifdef CONFIG_BLK_DEV_ZONED
static int linear_end_io(struct dm_target *ti, struct bio *bio,
blk_status_t *error)
{
struct linear_c *lc = ti->private;
if (!*error && bio_op(bio) == REQ_OP_ZONE_REPORT)
dm_remap_zone_report(ti, bio, lc->start);
return DM_ENDIO_DONE;
}
#endif
static void linear_status(struct dm_target *ti, status_type_t type,
unsigned status_flags, char *result, unsigned maxlen)
{
@@ -148,6 +135,26 @@ static int linear_prepare_ioctl(struct dm_target *ti, struct block_device **bdev
return 0;
}
#ifdef CONFIG_BLK_DEV_ZONED
static int linear_report_zones(struct dm_target *ti, sector_t sector,
struct blk_zone *zones, unsigned int *nr_zones,
gfp_t gfp_mask)
{
struct linear_c *lc = (struct linear_c *) ti->private;
int ret;
/* Do report and remap it */
ret = blkdev_report_zones(lc->dev->bdev, linear_map_sector(ti, sector),
zones, nr_zones, gfp_mask);
if (ret != 0)
return ret;
if (*nr_zones)
dm_remap_zone_report(ti, lc->start, zones, nr_zones);
return 0;
}
#endif
static int linear_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
@@ -211,8 +218,8 @@ static struct target_type linear_target = {
.name = "linear",
.version = {1, 4, 0},
#ifdef CONFIG_BLK_DEV_ZONED
.end_io = linear_end_io,
.features = DM_TARGET_PASSES_INTEGRITY | DM_TARGET_ZONED_HM,
.report_zones = linear_report_zones,
#else
.features = DM_TARGET_PASSES_INTEGRITY,
#endif