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|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2017 Western Digital Corporation or its affiliates.
*
* This file is released under the GPL.
*/
#include "dm-zoned.h"
#include <linux/module.h>
#define DM_MSG_PREFIX "zoned"
#define DMZ_MIN_BIOS 8192
/*
* Zone BIO context.
*/
struct dmz_bioctx {
struct dmz_target *target;
struct dm_zone *zone;
struct bio *bio;
refcount_t ref;
};
/*
* Chunk work descriptor.
*/
struct dm_chunk_work {
struct work_struct work;
refcount_t refcount;
struct dmz_target *target;
unsigned int chunk;
struct bio_list bio_list;
};
/*
* Target descriptor.
*/
struct dmz_target {
struct dm_dev *ddev;
unsigned long flags;
/* Zoned block device information */
struct dmz_dev *dev;
/* For metadata handling */
struct dmz_metadata *metadata;
/* For reclaim */
struct dmz_reclaim *reclaim;
/* For chunk work */
struct radix_tree_root chunk_rxtree;
struct workqueue_struct *chunk_wq;
struct mutex chunk_lock;
/* For cloned BIOs to zones */
struct bio_set bio_set;
/* For flush */
spinlock_t flush_lock;
struct bio_list flush_list;
struct delayed_work flush_work;
struct workqueue_struct *flush_wq;
};
/*
* Flush intervals (seconds).
*/
#define DMZ_FLUSH_PERIOD (10 * HZ)
/*
* Target BIO completion.
*/
static inline void dmz_bio_endio(struct bio *bio, blk_status_t status)
{
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
if (status != BLK_STS_OK && bio->bi_status == BLK_STS_OK)
bio->bi_status = status;
if (bio->bi_status != BLK_STS_OK)
bioctx->target->dev->flags |= DMZ_CHECK_BDEV;
if (refcount_dec_and_test(&bioctx->ref)) {
struct dm_zone *zone = bioctx->zone;
if (zone) {
if (bio->bi_status != BLK_STS_OK &&
bio_op(bio) == REQ_OP_WRITE &&
dmz_is_seq(zone))
set_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
dmz_deactivate_zone(zone);
}
bio_endio(bio);
}
}
/*
* Completion callback for an internally cloned target BIO. This terminates the
* target BIO when there are no more references to its context.
*/
static void dmz_clone_endio(struct bio *clone)
{
struct dmz_bioctx *bioctx = clone->bi_private;
blk_status_t status = clone->bi_status;
bio_put(clone);
dmz_bio_endio(bioctx->bio, status);
}
/*
* Issue a clone of a target BIO. The clone may only partially process the
* original target BIO.
*/
static int dmz_submit_bio(struct dmz_target *dmz, struct dm_zone *zone,
struct bio *bio, sector_t chunk_block,
unsigned int nr_blocks)
{
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
struct bio *clone;
clone = bio_clone_fast(bio, GFP_NOIO, &dmz->bio_set);
if (!clone)
return -ENOMEM;
bio_set_dev(clone, dmz->dev->bdev);
clone->bi_iter.bi_sector =
dmz_start_sect(dmz->metadata, zone) + dmz_blk2sect(chunk_block);
clone->bi_iter.bi_size = dmz_blk2sect(nr_blocks) << SECTOR_SHIFT;
clone->bi_end_io = dmz_clone_endio;
clone->bi_private = bioctx;
bio_advance(bio, clone->bi_iter.bi_size);
refcount_inc(&bioctx->ref);
generic_make_request(clone);
if (bio_op(bio) == REQ_OP_WRITE && dmz_is_seq(zone))
zone->wp_block += nr_blocks;
return 0;
}
/*
* Zero out pages of discarded blocks accessed by a read BIO.
*/
static void dmz_handle_read_zero(struct dmz_target *dmz, struct bio *bio,
sector_t chunk_block, unsigned int nr_blocks)
{
unsigned int size = nr_blocks << DMZ_BLOCK_SHIFT;
/* Clear nr_blocks */
swap(bio->bi_iter.bi_size, size);
zero_fill_bio(bio);
swap(bio->bi_iter.bi_size, size);
bio_advance(bio, size);
}
/*
* Process a read BIO.
*/
static int dmz_handle_read(struct dmz_target *dmz, struct dm_zone *zone,
struct bio *bio)
{
sector_t chunk_block = dmz_chunk_block(dmz->dev, dmz_bio_block(bio));
unsigned int nr_blocks = dmz_bio_blocks(bio);
sector_t end_block = chunk_block + nr_blocks;
struct dm_zone *rzone, *bzone;
int ret;
/* Read into unmapped chunks need only zeroing the BIO buffer */
if (!zone) {
zero_fill_bio(bio);
return 0;
}
dmz_dev_debug(dmz->dev, "READ chunk %llu -> %s zone %u, block %llu, %u blocks",
(unsigned long long)dmz_bio_chunk(dmz->dev, bio),
(dmz_is_rnd(zone) ? "RND" : "SEQ"),
dmz_id(dmz->metadata, zone),
(unsigned long long)chunk_block, nr_blocks);
/* Check block validity to determine the read location */
bzone = zone->bzone;
while (chunk_block < end_block) {
nr_blocks = 0;
if (dmz_is_rnd(zone) || chunk_block < zone->wp_block) {
/* Test block validity in the data zone */
ret = dmz_block_valid(dmz->metadata, zone, chunk_block);
if (ret < 0)
return ret;
if (ret > 0) {
/* Read data zone blocks */
nr_blocks = ret;
rzone = zone;
}
}
/*
* No valid blocks found in the data zone.
* Check the buffer zone, if there is one.
*/
if (!nr_blocks && bzone) {
ret = dmz_block_valid(dmz->metadata, bzone, chunk_block);
if (ret < 0)
return ret;
if (ret > 0) {
/* Read buffer zone blocks */
nr_blocks = ret;
rzone = bzone;
}
}
if (nr_blocks) {
/* Valid blocks found: read them */
nr_blocks = min_t(unsigned int, nr_blocks, end_block - chunk_block);
ret = dmz_submit_bio(dmz, rzone, bio, chunk_block, nr_blocks);
if (ret)
return ret;
chunk_block += nr_blocks;
} else {
/* No valid block: zeroout the current BIO block */
dmz_handle_read_zero(dmz, bio, chunk_block, 1);
chunk_block++;
}
}
return 0;
}
/*
* Write blocks directly in a data zone, at the write pointer.
* If a buffer zone is assigned, invalidate the blocks written
* in place.
*/
static int dmz_handle_direct_write(struct dmz_target *dmz,
struct dm_zone *zone, struct bio *bio,
sector_t chunk_block,
unsigned int nr_blocks)
{
struct dmz_metadata *zmd = dmz->metadata;
struct dm_zone *bzone = zone->bzone;
int ret;
if (dmz_is_readonly(zone))
return -EROFS;
/* Submit write */
ret = dmz_submit_bio(dmz, zone, bio, chunk_block, nr_blocks);
if (ret)
return ret;
/*
* Validate the blocks in the data zone and invalidate
* in the buffer zone, if there is one.
*/
ret = dmz_validate_blocks(zmd, zone, chunk_block, nr_blocks);
if (ret == 0 && bzone)
ret = dmz_invalidate_blocks(zmd, bzone, chunk_block, nr_blocks);
return ret;
}
/*
* Write blocks in the buffer zone of @zone.
* If no buffer zone is assigned yet, get one.
* Called with @zone write locked.
*/
static int dmz_handle_buffered_write(struct dmz_target *dmz,
struct dm_zone *zone, struct bio *bio,
sector_t chunk_block,
unsigned int nr_blocks)
{
struct dmz_metadata *zmd = dmz->metadata;
struct dm_zone *bzone;
int ret;
/* Get the buffer zone. One will be allocated if needed */
bzone = dmz_get_chunk_buffer(zmd, zone);
if (IS_ERR(bzone))
return PTR_ERR(bzone);
if (dmz_is_readonly(bzone))
return -EROFS;
/* Submit write */
ret = dmz_submit_bio(dmz, bzone, bio, chunk_block, nr_blocks);
if (ret)
return ret;
/*
* Validate the blocks in the buffer zone
* and invalidate in the data zone.
*/
ret = dmz_validate_blocks(zmd, bzone, chunk_block, nr_blocks);
if (ret == 0 && chunk_block < zone->wp_block)
ret = dmz_invalidate_blocks(zmd, zone, chunk_block, nr_blocks);
return ret;
}
/*
* Process a write BIO.
*/
static int dmz_handle_write(struct dmz_target *dmz, struct dm_zone *zone,
struct bio *bio)
{
sector_t chunk_block = dmz_chunk_block(dmz->dev, dmz_bio_block(bio));
unsigned int nr_blocks = dmz_bio_blocks(bio);
if (!zone)
return -ENOSPC;
dmz_dev_debug(dmz->dev, "WRITE chunk %llu -> %s zone %u, block %llu, %u blocks",
(unsigned long long)dmz_bio_chunk(dmz->dev, bio),
(dmz_is_rnd(zone) ? "RND" : "SEQ"),
dmz_id(dmz->metadata, zone),
(unsigned long long)chunk_block, nr_blocks);
if (dmz_is_rnd(zone) || chunk_block == zone->wp_block) {
/*
* zone is a random zone or it is a sequential zone
* and the BIO is aligned to the zone write pointer:
* direct write the zone.
*/
return dmz_handle_direct_write(dmz, zone, bio, chunk_block, nr_blocks);
}
/*
* This is an unaligned write in a sequential zone:
* use buffered write.
*/
return dmz_handle_buffered_write(dmz, zone, bio, chunk_block, nr_blocks);
}
/*
* Process a discard BIO.
*/
static int dmz_handle_discard(struct dmz_target *dmz, struct dm_zone *zone,
struct bio *bio)
{
struct dmz_metadata *zmd = dmz->metadata;
sector_t block = dmz_bio_block(bio);
unsigned int nr_blocks = dmz_bio_blocks(bio);
sector_t chunk_block = dmz_chunk_block(dmz->dev, block);
int ret = 0;
/* For unmapped chunks, there is nothing to do */
if (!zone)
return 0;
if (dmz_is_readonly(zone))
return -EROFS;
dmz_dev_debug(dmz->dev, "DISCARD chunk %llu -> zone %u, block %llu, %u blocks",
(unsigned long long)dmz_bio_chunk(dmz->dev, bio),
dmz_id(zmd, zone),
(unsigned long long)chunk_block, nr_blocks);
/*
* Invalidate blocks in the data zone and its
* buffer zone if one is mapped.
*/
if (dmz_is_rnd(zone) || chunk_block < zone->wp_block)
ret = dmz_invalidate_blocks(zmd, zone, chunk_block, nr_blocks);
if (ret == 0 && zone->bzone)
ret = dmz_invalidate_blocks(zmd, zone->bzone,
chunk_block, nr_blocks);
return ret;
}
/*
* Process a BIO.
*/
static void dmz_handle_bio(struct dmz_target *dmz, struct dm_chunk_work *cw,
struct bio *bio)
{
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
struct dmz_metadata *zmd = dmz->metadata;
struct dm_zone *zone;
int ret;
/*
* Write may trigger a zone allocation. So make sure the
* allocation can succeed.
*/
if (bio_op(bio) == REQ_OP_WRITE)
dmz_schedule_reclaim(dmz->reclaim);
dmz_lock_metadata(zmd);
if (dmz->dev->flags & DMZ_BDEV_DYING) {
ret = -EIO;
goto out;
}
/*
* Get the data zone mapping the chunk. There may be no
* mapping for read and discard. If a mapping is obtained,
+ the zone returned will be set to active state.
*/
zone = dmz_get_chunk_mapping(zmd, dmz_bio_chunk(dmz->dev, bio),
bio_op(bio));
if (IS_ERR(zone)) {
ret = PTR_ERR(zone);
goto out;
}
/* Process the BIO */
if (zone) {
dmz_activate_zone(zone);
bioctx->zone = zone;
}
switch (bio_op(bio)) {
case REQ_OP_READ:
ret = dmz_handle_read(dmz, zone, bio);
break;
case REQ_OP_WRITE:
ret = dmz_handle_write(dmz, zone, bio);
break;
case REQ_OP_DISCARD:
case REQ_OP_WRITE_ZEROES:
ret = dmz_handle_discard(dmz, zone, bio);
break;
default:
dmz_dev_err(dmz->dev, "Unsupported BIO operation 0x%x",
bio_op(bio));
ret = -EIO;
}
/*
* Release the chunk mapping. This will check that the mapping
* is still valid, that is, that the zone used still has valid blocks.
*/
if (zone)
dmz_put_chunk_mapping(zmd, zone);
out:
dmz_bio_endio(bio, errno_to_blk_status(ret));
dmz_unlock_metadata(zmd);
}
/*
* Increment a chunk reference counter.
*/
static inline void dmz_get_chunk_work(struct dm_chunk_work *cw)
{
refcount_inc(&cw->refcount);
}
/*
* Decrement a chunk work reference count and
* free it if it becomes 0.
*/
static void dmz_put_chunk_work(struct dm_chunk_work *cw)
{
if (refcount_dec_and_test(&cw->refcount)) {
WARN_ON(!bio_list_empty(&cw->bio_list));
radix_tree_delete(&cw->target->chunk_rxtree, cw->chunk);
kfree(cw);
}
}
/*
* Chunk BIO work function.
*/
static void dmz_chunk_work(struct work_struct *work)
{
struct dm_chunk_work *cw = container_of(work, struct dm_chunk_work, work);
struct dmz_target *dmz = cw->target;
struct bio *bio;
mutex_lock(&dmz->chunk_lock);
/* Process the chunk BIOs */
while ((bio = bio_list_pop(&cw->bio_list))) {
mutex_unlock(&dmz->chunk_lock);
dmz_handle_bio(dmz, cw, bio);
mutex_lock(&dmz->chunk_lock);
dmz_put_chunk_work(cw);
}
/* Queueing the work incremented the work refcount */
dmz_put_chunk_work(cw);
mutex_unlock(&dmz->chunk_lock);
}
/*
* Flush work.
*/
static void dmz_flush_work(struct work_struct *work)
{
struct dmz_target *dmz = container_of(work, struct dmz_target, flush_work.work);
struct bio *bio;
int ret;
/* Flush dirty metadata blocks */
ret = dmz_flush_metadata(dmz->metadata);
if (ret)
dmz_dev_debug(dmz->dev, "Metadata flush failed, rc=%d\n", ret);
/* Process queued flush requests */
while (1) {
spin_lock(&dmz->flush_lock);
bio = bio_list_pop(&dmz->flush_list);
spin_unlock(&dmz->flush_lock);
if (!bio)
break;
dmz_bio_endio(bio, errno_to_blk_status(ret));
}
queue_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
}
/*
* Get a chunk work and start it to process a new BIO.
* If the BIO chunk has no work yet, create one.
*/
static int dmz_queue_chunk_work(struct dmz_target *dmz, struct bio *bio)
{
unsigned int chunk = dmz_bio_chunk(dmz->dev, bio);
struct dm_chunk_work *cw;
int ret = 0;
mutex_lock(&dmz->chunk_lock);
/* Get the BIO chunk work. If one is not active yet, create one */
cw = radix_tree_lookup(&dmz->chunk_rxtree, chunk);
if (!cw) {
/* Create a new chunk work */
cw = kmalloc(sizeof(struct dm_chunk_work), GFP_NOIO);
if (unlikely(!cw)) {
ret = -ENOMEM;
goto out;
}
INIT_WORK(&cw->work, dmz_chunk_work);
refcount_set(&cw->refcount, 0);
cw->target = dmz;
cw->chunk = chunk;
bio_list_init(&cw->bio_list);
ret = radix_tree_insert(&dmz->chunk_rxtree, chunk, cw);
if (unlikely(ret)) {
kfree(cw);
goto out;
}
}
bio_list_add(&cw->bio_list, bio);
dmz_get_chunk_work(cw);
dmz_reclaim_bio_acc(dmz->reclaim);
if (queue_work(dmz->chunk_wq, &cw->work))
dmz_get_chunk_work(cw);
out:
mutex_unlock(&dmz->chunk_lock);
return ret;
}
/*
* Check if the backing device is being removed. If it's on the way out,
* start failing I/O. Reclaim and metadata components also call this
* function to cleanly abort operation in the event of such failure.
*/
bool dmz_bdev_is_dying(struct dmz_dev *dmz_dev)
{
if (dmz_dev->flags & DMZ_BDEV_DYING)
return true;
if (dmz_dev->flags & DMZ_CHECK_BDEV)
return !dmz_check_bdev(dmz_dev);
if (blk_queue_dying(bdev_get_queue(dmz_dev->bdev))) {
dmz_dev_warn(dmz_dev, "Backing device queue dying");
dmz_dev->flags |= DMZ_BDEV_DYING;
}
return dmz_dev->flags & DMZ_BDEV_DYING;
}
/*
* Check the backing device availability. This detects such events as
* backing device going offline due to errors, media removals, etc.
* This check is less efficient than dmz_bdev_is_dying() and should
* only be performed as a part of error handling.
*/
bool dmz_check_bdev(struct dmz_dev *dmz_dev)
{
struct gendisk *disk;
dmz_dev->flags &= ~DMZ_CHECK_BDEV;
if (dmz_bdev_is_dying(dmz_dev))
return false;
disk = dmz_dev->bdev->bd_disk;
if (disk->fops->check_events &&
disk->fops->check_events(disk, 0) & DISK_EVENT_MEDIA_CHANGE) {
dmz_dev_warn(dmz_dev, "Backing device offline");
dmz_dev->flags |= DMZ_BDEV_DYING;
}
return !(dmz_dev->flags & DMZ_BDEV_DYING);
}
/*
* Process a new BIO.
*/
static int dmz_map(struct dm_target *ti, struct bio *bio)
{
struct dmz_target *dmz = ti->private;
struct dmz_dev *dev = dmz->dev;
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
sector_t sector = bio->bi_iter.bi_sector;
unsigned int nr_sectors = bio_sectors(bio);
sector_t chunk_sector;
int ret;
if (dmz_bdev_is_dying(dmz->dev))
return DM_MAPIO_KILL;
dmz_dev_debug(dev, "BIO op %d sector %llu + %u => chunk %llu, block %llu, %u blocks",
bio_op(bio), (unsigned long long)sector, nr_sectors,
(unsigned long long)dmz_bio_chunk(dmz->dev, bio),
(unsigned long long)dmz_chunk_block(dmz->dev, dmz_bio_block(bio)),
(unsigned int)dmz_bio_blocks(bio));
bio_set_dev(bio, dev->bdev);
if (!nr_sectors && bio_op(bio) != REQ_OP_WRITE)
return DM_MAPIO_REMAPPED;
/* The BIO should be block aligned */
if ((nr_sectors & DMZ_BLOCK_SECTORS_MASK) || (sector & DMZ_BLOCK_SECTORS_MASK))
return DM_MAPIO_KILL;
/* Initialize the BIO context */
bioctx->target = dmz;
bioctx->zone = NULL;
bioctx->bio = bio;
refcount_set(&bioctx->ref, 1);
/* Set the BIO pending in the flush list */
if (!nr_sectors && bio_op(bio) == REQ_OP_WRITE) {
spin_lock(&dmz->flush_lock);
bio_list_add(&dmz->flush_list, bio);
spin_unlock(&dmz->flush_lock);
mod_delayed_work(dmz->flush_wq, &dmz->flush_work, 0);
return DM_MAPIO_SUBMITTED;
}
/* Split zone BIOs to fit entirely into a zone */
chunk_sector = sector & (dev->zone_nr_sectors - 1);
if (chunk_sector + nr_sectors > dev->zone_nr_sectors)
dm_accept_partial_bio(bio, dev->zone_nr_sectors - chunk_sector);
/* Now ready to handle this BIO */
ret = dmz_queue_chunk_work(dmz, bio);
if (ret) {
dmz_dev_debug(dmz->dev,
"BIO op %d, can't process chunk %llu, err %i\n",
bio_op(bio), (u64)dmz_bio_chunk(dmz->dev, bio),
ret);
return DM_MAPIO_REQUEUE;
}
return DM_MAPIO_SUBMITTED;
}
/*
* Get zoned device information.
*/
static int dmz_get_zoned_device(struct dm_target *ti, char *path)
{
struct dmz_target *dmz = ti->private;
struct request_queue *q;
struct dmz_dev *dev;
sector_t aligned_capacity;
int ret;
/* Get the target device */
ret = dm_get_device(ti, path, dm_table_get_mode(ti->table), &dmz->ddev);
if (ret) {
ti->error = "Get target device failed";
dmz->ddev = NULL;
return ret;
}
dev = kzalloc(sizeof(struct dmz_dev), GFP_KERNEL);
if (!dev) {
ret = -ENOMEM;
goto err;
}
dev->bdev = dmz->ddev->bdev;
(void)bdevname(dev->bdev, dev->name);
if (bdev_zoned_model(dev->bdev) == BLK_ZONED_NONE) {
ti->error = "Not a zoned block device";
ret = -EINVAL;
goto err;
}
q = bdev_get_queue(dev->bdev);
dev->capacity = i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT;
aligned_capacity = dev->capacity &
~((sector_t)blk_queue_zone_sectors(q) - 1);
if (ti->begin ||
((ti->len != dev->capacity) && (ti->len != aligned_capacity))) {
ti->error = "Partial mapping not supported";
ret = -EINVAL;
goto err;
}
dev->zone_nr_sectors = blk_queue_zone_sectors(q);
dev->zone_nr_sectors_shift = ilog2(dev->zone_nr_sectors);
dev->zone_nr_blocks = dmz_sect2blk(dev->zone_nr_sectors);
dev->zone_nr_blocks_shift = ilog2(dev->zone_nr_blocks);
dev->nr_zones = blkdev_nr_zones(dev->bdev);
dmz->dev = dev;
return 0;
err:
dm_put_device(ti, dmz->ddev);
kfree(dev);
return ret;
}
/*
* Cleanup zoned device information.
*/
static void dmz_put_zoned_device(struct dm_target *ti)
{
struct dmz_target *dmz = ti->private;
dm_put_device(ti, dmz->ddev);
kfree(dmz->dev);
dmz->dev = NULL;
}
/*
* Setup target.
*/
static int dmz_ctr(struct dm_target *ti, unsigned int argc, char **argv)
{
struct dmz_target *dmz;
struct dmz_dev *dev;
int ret;
/* Check arguments */
if (argc != 1) {
ti->error = "Invalid argument count";
return -EINVAL;
}
/* Allocate and initialize the target descriptor */
dmz = kzalloc(sizeof(struct dmz_target), GFP_KERNEL);
if (!dmz) {
ti->error = "Unable to allocate the zoned target descriptor";
return -ENOMEM;
}
ti->private = dmz;
/* Get the target zoned block device */
ret = dmz_get_zoned_device(ti, argv[0]);
if (ret) {
dmz->ddev = NULL;
goto err;
}
/* Initialize metadata */
dev = dmz->dev;
ret = dmz_ctr_metadata(dev, &dmz->metadata);
if (ret) {
ti->error = "Metadata initialization failed";
goto err_dev;
}
/* Set target (no write same support) */
ti->max_io_len = dev->zone_nr_sectors << 9;
ti->num_flush_bios = 1;
ti->num_discard_bios = 1;
ti->num_write_zeroes_bios = 1;
ti->per_io_data_size = sizeof(struct dmz_bioctx);
ti->flush_supported = true;
ti->discards_supported = true;
/* The exposed capacity is the number of chunks that can be mapped */
ti->len = (sector_t)dmz_nr_chunks(dmz->metadata) << dev->zone_nr_sectors_shift;
/* Zone BIO */
ret = bioset_init(&dmz->bio_set, DMZ_MIN_BIOS, 0, 0);
if (ret) {
ti->error = "Create BIO set failed";
goto err_meta;
}
/* Chunk BIO work */
mutex_init(&dmz->chunk_lock);
INIT_RADIX_TREE(&dmz->chunk_rxtree, GFP_NOIO);
dmz->chunk_wq = alloc_workqueue("dmz_cwq_%s", WQ_MEM_RECLAIM | WQ_UNBOUND,
0, dev->name);
if (!dmz->chunk_wq) {
ti->error = "Create chunk workqueue failed";
ret = -ENOMEM;
goto err_bio;
}
/* Flush work */
spin_lock_init(&dmz->flush_lock);
bio_list_init(&dmz->flush_list);
INIT_DELAYED_WORK(&dmz->flush_work, dmz_flush_work);
dmz->flush_wq = alloc_ordered_workqueue("dmz_fwq_%s", WQ_MEM_RECLAIM,
dev->name);
if (!dmz->flush_wq) {
ti->error = "Create flush workqueue failed";
ret = -ENOMEM;
goto err_cwq;
}
mod_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
/* Initialize reclaim */
ret = dmz_ctr_reclaim(dev, dmz->metadata, &dmz->reclaim);
if (ret) {
ti->error = "Zone reclaim initialization failed";
goto err_fwq;
}
dmz_dev_info(dev, "Target device: %llu 512-byte logical sectors (%llu blocks)",
(unsigned long long)ti->len,
(unsigned long long)dmz_sect2blk(ti->len));
return 0;
err_fwq:
destroy_workqueue(dmz->flush_wq);
err_cwq:
destroy_workqueue(dmz->chunk_wq);
err_bio:
mutex_destroy(&dmz->chunk_lock);
bioset_exit(&dmz->bio_set);
err_meta:
dmz_dtr_metadata(dmz->metadata);
err_dev:
dmz_put_zoned_device(ti);
err:
kfree(dmz);
return ret;
}
/*
* Cleanup target.
*/
static void dmz_dtr(struct dm_target *ti)
{
struct dmz_target *dmz = ti->private;
flush_workqueue(dmz->chunk_wq);
destroy_workqueue(dmz->chunk_wq);
dmz_dtr_reclaim(dmz->reclaim);
cancel_delayed_work_sync(&dmz->flush_work);
destroy_workqueue(dmz->flush_wq);
(void) dmz_flush_metadata(dmz->metadata);
dmz_dtr_metadata(dmz->metadata);
bioset_exit(&dmz->bio_set);
dmz_put_zoned_device(ti);
mutex_destroy(&dmz->chunk_lock);
kfree(dmz);
}
/*
* Setup target request queue limits.
*/
static void dmz_io_hints(struct dm_target *ti, struct queue_limits *limits)
{
struct dmz_target *dmz = ti->private;
unsigned int chunk_sectors = dmz->dev->zone_nr_sectors;
limits->logical_block_size = DMZ_BLOCK_SIZE;
limits->physical_block_size = DMZ_BLOCK_SIZE;
blk_limits_io_min(limits, DMZ_BLOCK_SIZE);
blk_limits_io_opt(limits, DMZ_BLOCK_SIZE);
limits->discard_alignment = DMZ_BLOCK_SIZE;
limits->discard_granularity = DMZ_BLOCK_SIZE;
limits->max_discard_sectors = chunk_sectors;
limits->max_hw_discard_sectors = chunk_sectors;
limits->max_write_zeroes_sectors = chunk_sectors;
/* FS hint to try to align to the device zone size */
limits->chunk_sectors = chunk_sectors;
limits->max_sectors = chunk_sectors;
/* We are exposing a drive-managed zoned block device */
limits->zoned = BLK_ZONED_NONE;
}
/*
* Pass on ioctl to the backend device.
*/
static int dmz_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
{
struct dmz_target *dmz = ti->private;
if (!dmz_check_bdev(dmz->dev))
return -EIO;
*bdev = dmz->dev->bdev;
return 0;
}
/*
* Stop works on suspend.
*/
static void dmz_suspend(struct dm_target *ti)
{
struct dmz_target *dmz = ti->private;
flush_workqueue(dmz->chunk_wq);
dmz_suspend_reclaim(dmz->reclaim);
cancel_delayed_work_sync(&dmz->flush_work);
}
/*
* Restart works on resume or if suspend failed.
*/
static void dmz_resume(struct dm_target *ti)
{
struct dmz_target *dmz = ti->private;
queue_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
dmz_resume_reclaim(dmz->reclaim);
}
static int dmz_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
struct dmz_target *dmz = ti->private;
struct dmz_dev *dev = dmz->dev;
sector_t capacity = dev->capacity & ~(dev->zone_nr_sectors - 1);
return fn(ti, dmz->ddev, 0, capacity, data);
}
static struct target_type dmz_type = {
.name = "zoned",
.version = {1, 0, 0},
.features = DM_TARGET_SINGLETON | DM_TARGET_ZONED_HM,
.module = THIS_MODULE,
.ctr = dmz_ctr,
.dtr = dmz_dtr,
.map = dmz_map,
.io_hints = dmz_io_hints,
.prepare_ioctl = dmz_prepare_ioctl,
.postsuspend = dmz_suspend,
.resume = dmz_resume,
.iterate_devices = dmz_iterate_devices,
};
static int __init dmz_init(void)
{
return dm_register_target(&dmz_type);
}
static void __exit dmz_exit(void)
{
dm_unregister_target(&dmz_type);
}
module_init(dmz_init);
module_exit(dmz_exit);
MODULE_DESCRIPTION(DM_NAME " target for zoned block devices");
MODULE_AUTHOR("Damien Le Moal <damien.lemoal@wdc.com>");
MODULE_LICENSE("GPL");
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