[PATCH 19/30] nbd: use blk_mq_alloc_disk and blk_cleanup_disk

Christoph Hellwig
2021-06-02T07:28:41Z

Use blk_mq_alloc_disk and blk_cleanup_disk to simplify the gendisk and
request_queue allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/block/nbd.c | 53 ++++++++++++++++++---------------------------
1 file changed, 21 insertions(+), 32 deletions(-)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 45d2c28c8fc8..614d82e7fae4 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -219,15 +219,11 @@ static const struct device_attribute pid_attr = {
static void nbd_dev_remove(struct nbd_device *nbd)
{
struct gendisk *disk = nbd->disk;
- struct request_queue *q;

if (disk) {
- q = disk->queue;
del_gendisk(disk);
- blk_cleanup_queue(q);
blk_mq_free_tag_set(&nbd->tag_set);
- disk->private_data = NULL;
- put_disk(disk);
+ blk_cleanup_disk(disk);
}

/*
@@ -1646,15 +1642,24 @@ static int nbd_dev_add(int index)
{
struct nbd_device *nbd;
struct gendisk *disk;
- struct request_queue *q;
int err = -ENOMEM;

nbd = kzalloc(sizeof(struct nbd_device), GFP_KERNEL);
if (!nbd)
goto out;

- disk = alloc_disk(1 << part_shift);
- if (!disk)
+ nbd->tag_set.ops = &nbd_mq_ops;
+ nbd->tag_set.nr_hw_queues = 1;
+ nbd->tag_set.queue_depth = 128;
+ nbd->tag_set.numa_node = NUMA_NO_NODE;
+ nbd->tag_set.cmd_size = sizeof(struct nbd_cmd);
+ nbd->tag_set.flags = BLK_MQ_F_SHOULD_MERGE |
+ BLK_MQ_F_BLOCKING;
+ nbd->tag_set.driver_data = nbd;
+ nbd->destroy_complete = NULL;
+
+ err = blk_mq_alloc_tag_set(&nbd->tag_set);
+ if (err)
goto out_free_nbd;

if (index >= 0) {
@@ -1668,30 +1673,15 @@ static int nbd_dev_add(int index)
index = err;
}
if (err < 0)
- goto out_free_disk;
-
+ goto out_free_tags;
nbd->index = index;
- nbd->disk = disk;
- nbd->tag_set.ops = &nbd_mq_ops;
- nbd->tag_set.nr_hw_queues = 1;
- nbd->tag_set.queue_depth = 128;
- nbd->tag_set.numa_node = NUMA_NO_NODE;
- nbd->tag_set.cmd_size = sizeof(struct nbd_cmd);
- nbd->tag_set.flags = BLK_MQ_F_SHOULD_MERGE |
- BLK_MQ_F_BLOCKING;
- nbd->tag_set.driver_data = nbd;
- nbd->destroy_complete = NULL;

- err = blk_mq_alloc_tag_set(&nbd->tag_set);
- if (err)
+ disk = blk_mq_alloc_disk(&nbd->tag_set, NULL);
+ if (IS_ERR(disk)) {
+ err = PTR_ERR(disk);
goto out_free_idr;
-
- q = blk_mq_init_queue(&nbd->tag_set);
- if (IS_ERR(q)) {
- err = PTR_ERR(q);
- goto out_free_tags;
}
- disk->queue = q;
+ nbd->disk = disk;

/*
* Tell the block layer that we are not a rotational device
@@ -1712,6 +1702,7 @@ static int nbd_dev_add(int index)
INIT_LIST_HEAD(&nbd->list);
disk->major = NBD_MAJOR;
disk->first_minor = index << part_shift;
+ disk->minors = 1 << part_shift;
disk->fops = &nbd_fops;
disk->private_data = nbd;
sprintf(disk->disk_name, "nbd%d", index);
@@ -1719,12 +1710,10 @@ static int nbd_dev_add(int index)
nbd_total_devices++;
return index;

-out_free_tags:
- blk_mq_free_tag_set(&nbd->tag_set);
out_free_idr:
idr_remove(&nbd_index_idr, index);
-out_free_disk:
- put_disk(disk);
+out_free_tags:
+ blk_mq_free_tag_set(&nbd->tag_set);
out_free_nbd:
kfree(nbd);