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path: root/drivers/md/dm-zoned-target.c
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Diffstat (limited to 'drivers/md/dm-zoned-target.c')
-rw-r--r--drivers/md/dm-zoned-target.c967
1 files changed, 967 insertions, 0 deletions
diff --git a/drivers/md/dm-zoned-target.c b/drivers/md/dm-zoned-target.c
new file mode 100644
index 000000000000..2b538fa817f4
--- /dev/null
+++ b/drivers/md/dm-zoned-target.c
@@ -0,0 +1,967 @@
+/*
+ * 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;
+ atomic_t ref;
+ blk_status_t status;
+};
+
+/*
+ * Chunk work descriptor.
+ */
+struct dm_chunk_work {
+ struct work_struct work;
+ atomic_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 mutex chunk_lock;
+ struct radix_tree_root chunk_rxtree;
+ struct workqueue_struct *chunk_wq;
+
+ /* 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 (bioctx->status == BLK_STS_OK && status != BLK_STS_OK)
+ bioctx->status = status;
+ bio_endio(bio);
+}
+
+/*
+ * Partial clone read BIO completion callback. This terminates the
+ * target BIO when there are no more references to its context.
+ */
+static void dmz_read_bio_end_io(struct bio *bio)
+{
+ struct dmz_bioctx *bioctx = bio->bi_private;
+ blk_status_t status = bio->bi_status;
+
+ bio_put(bio);
+ dmz_bio_endio(bioctx->bio, status);
+}
+
+/*
+ * Issue a BIO to a zone. The BIO may only partially process the
+ * original target BIO.
+ */
+static int dmz_submit_read_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));
+ sector_t sector;
+ struct bio *clone;
+
+ /* BIO remap sector */
+ sector = dmz_start_sect(dmz->metadata, zone) + dmz_blk2sect(chunk_block);
+
+ /* If the read is not partial, there is no need to clone the BIO */
+ if (nr_blocks == dmz_bio_blocks(bio)) {
+ /* Setup and submit the BIO */
+ bio->bi_iter.bi_sector = sector;
+ atomic_inc(&bioctx->ref);
+ generic_make_request(bio);
+ return 0;
+ }
+
+ /* Partial BIO: we need to clone the BIO */
+ clone = bio_clone_fast(bio, GFP_NOIO, dmz->bio_set);
+ if (!clone)
+ return -ENOMEM;
+
+ /* Setup the clone */
+ clone->bi_iter.bi_sector = sector;
+ clone->bi_iter.bi_size = dmz_blk2sect(nr_blocks) << SECTOR_SHIFT;
+ clone->bi_end_io = dmz_read_bio_end_io;
+ clone->bi_private = bioctx;
+
+ bio_advance(bio, clone->bi_iter.bi_size);
+
+ /* Submit the clone */
+ atomic_inc(&bioctx->ref);
+ generic_make_request(clone);
+
+ 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_read_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;
+}
+
+/*
+ * Issue a write BIO to a zone.
+ */
+static void dmz_submit_write_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));
+
+ /* Setup and submit the BIO */
+ bio->bi_bdev = dmz->dev->bdev;
+ bio->bi_iter.bi_sector = dmz_start_sect(dmz->metadata, zone) + dmz_blk2sect(chunk_block);
+ atomic_inc(&bioctx->ref);
+ generic_make_request(bio);
+
+ if (dmz_is_seq(zone))
+ zone->wp_block += nr_blocks;
+}
+
+/*
+ * 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 */
+ dmz_submit_write_bio(dmz, zone, bio, chunk_block, nr_blocks);
+
+ /*
+ * 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 (!bzone)
+ return -ENOSPC;
+
+ if (dmz_is_readonly(bzone))
+ return -EROFS;
+
+ /* Submit write */
+ dmz_submit_write_bio(dmz, bzone, bio, chunk_block, nr_blocks);
+
+ /*
+ * 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);
+
+ /*
+ * 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)
+{
+ atomic_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 (atomic_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);
+
+ /* 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 void 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;
+
+ 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) {
+ int ret;
+
+ /* Create a new chunk work */
+ cw = kmalloc(sizeof(struct dm_chunk_work), GFP_NOFS);
+ if (!cw)
+ goto out;
+
+ INIT_WORK(&cw->work, dmz_chunk_work);
+ atomic_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);
+ cw = NULL;
+ goto out;
+ }
+ }
+
+ bio_list_add(&cw->bio_list, bio);
+ dmz_get_chunk_work(cw);
+
+ if (queue_work(dmz->chunk_wq, &cw->work))
+ dmz_get_chunk_work(cw);
+out:
+ mutex_unlock(&dmz->chunk_lock);
+}
+
+/*
+ * 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;
+
+ 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->bi_bdev = dev->bdev;
+
+ if (!nr_sectors && (bio_op(bio) != REQ_OP_FLUSH) && (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;
+ atomic_set(&bioctx->ref, 1);
+ bioctx->status = BLK_STS_OK;
+
+ /* Set the BIO pending in the flush list */
+ if (bio_op(bio) == REQ_OP_FLUSH || (!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 */
+ dmz_reclaim_bio_acc(dmz->reclaim);
+ dmz_queue_chunk_work(dmz, bio);
+
+ return DM_MAPIO_SUBMITTED;
+}
+
+/*
+ * Completed target BIO processing.
+ */
+static int dmz_end_io(struct dm_target *ti, struct bio *bio, blk_status_t *error)
+{
+ struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
+
+ if (bioctx->status == BLK_STS_OK && *error)
+ bioctx->status = *error;
+
+ if (!atomic_dec_and_test(&bioctx->ref))
+ return DM_ENDIO_INCOMPLETE;
+
+ /* Done */
+ bio->bi_status = bioctx->status;
+
+ if (bioctx->zone) {
+ struct dm_zone *zone = bioctx->zone;
+
+ if (*error && bio_op(bio) == REQ_OP_WRITE) {
+ if (dmz_is_seq(zone))
+ set_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
+ }
+ dmz_deactivate_zone(zone);
+ }
+
+ return DM_ENDIO_DONE;
+}
+
+/*
+ * 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;
+ 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;
+ }
+
+ dev->capacity = i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT;
+ if (ti->begin || (ti->len != dev->capacity)) {
+ ti->error = "Partial mapping not supported";
+ ret = -EINVAL;
+ goto err;
+ }
+
+ q = bdev_get_queue(dev->bdev);
+ dev->zone_nr_sectors = q->limits.chunk_sectors;
+ 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 = (dev->capacity + dev->zone_nr_sectors - 1)
+ >> dev->zone_nr_sectors_shift;
+
+ 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;
+ ti->split_discard_bios = 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 */
+ dmz->bio_set = bioset_create(DMZ_MIN_BIOS, 0, 0);
+ if (!dmz->bio_set) {
+ ti->error = "Create BIO set failed";
+ ret = -ENOMEM;
+ goto err_meta;
+ }
+
+ /* Chunk BIO work */
+ mutex_init(&dmz->chunk_lock);
+ INIT_RADIX_TREE(&dmz->chunk_rxtree, GFP_NOFS);
+ 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:
+ bioset_free(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_free(dmz->bio_set);
+
+ dmz_put_zoned_device(ti);
+
+ 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, fmode_t *mode)
+{
+ struct dmz_target *dmz = ti->private;
+
+ *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;
+
+ return fn(ti, dmz->ddev, 0, dmz->dev->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,
+ .end_io = dmz_end_io,
+ .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");