From 6d2266f7ee5bb04b4852b8155ca0b35f8dda48aa Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 17:03:31 +0200
Subject: [PATCH 01/11] Remove cas_disk_claim()

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/cas_cache.h                |  1 -
 modules/cas_cache/disk.c                     | 27 --------------------
 modules/cas_cache/disk.h                     | 10 --------
 modules/cas_cache/exp_obj.c                  |  5 +++-
 modules/cas_cache/exp_obj.h                  |  3 ++-
 modules/cas_cache/volume/vol_block_dev_top.c | 12 ++-------
 6 files changed, 8 insertions(+), 50 deletions(-)

diff --git a/modules/cas_cache/cas_cache.h b/modules/cas_cache/cas_cache.h
index 23b3eb4..14bd124 100644
--- a/modules/cas_cache/cas_cache.h
+++ b/modules/cas_cache/cas_cache.h
@@ -51,7 +51,6 @@ enum {
 };
 
 struct cas_module {
-	struct list_head disk_list;
 	uint32_t next_disk_id;
 	int disk_major;
 	int next_minor;
diff --git a/modules/cas_cache/disk.c b/modules/cas_cache/disk.c
index 37d38db..75ca842 100644
--- a/modules/cas_cache/disk.c
+++ b/modules/cas_cache/disk.c
@@ -55,7 +55,6 @@ int __init cas_init_disks(void)
 	CAS_DEBUG_TRACE();
 
 	cas_module.next_disk_id = 1;
-	INIT_LIST_HEAD(&cas_module.disk_list);
 
 	cas_module.disk_major = register_blkdev(cas_module.disk_major,
 						  "cas");
@@ -131,7 +130,6 @@ struct cas_disk *cas_disk_open(const char *path, void *private)
 	dsk->private = private;
 
 	dsk->id = cas_module.next_disk_id++;
-	list_add(&dsk->list, &cas_module.disk_list);
 
 	result = _cas_disk_init_kobject(dsk);
 	if (result)
@@ -142,7 +140,6 @@ struct cas_disk *cas_disk_open(const char *path, void *private)
 	return dsk;
 
 error_kobject:
-	list_del(&dsk->list);
 	close_bdev_exclusive(dsk->bd, CAS_DISK_OPEN_FMODE);
 error_open_bdev:
 	kfree(dsk->path);
@@ -152,28 +149,6 @@ error_kmem:
 	return ERR_PTR(result);
 }
 
-static void _cas_disk_claim(struct cas_disk *dsk, void *private)
-{
-	dsk->private = private;
-}
-
-struct cas_disk *cas_disk_claim(const char *path, void *private)
-{
-	struct list_head *item;
-	struct cas_disk *dsk = NULL;
-
-	BUG_ON(!path);
-
-	list_for_each(item, &cas_module.disk_list) {
-		dsk = list_entry(item, struct cas_disk, list);
-		if (strncmp(path, dsk->path, PATH_MAX) == 0) {
-			_cas_disk_claim(dsk, private);
-			return dsk;
-		}
-	}
-	return NULL;
-}
-
 static void __cas_disk_close(struct cas_disk *dsk)
 {
 	close_bdev_exclusive(dsk->bd, CAS_DISK_OPEN_FMODE);
@@ -189,8 +164,6 @@ void cas_disk_close(struct cas_disk *dsk)
 
 	CAS_DEBUG_DISK(dsk, "Destroying (%p)", dsk);
 
-	list_del(&dsk->list);
-
 	__cas_disk_close(dsk);
 }
 
diff --git a/modules/cas_cache/disk.h b/modules/cas_cache/disk.h
index a2bab73..475b11a 100644
--- a/modules/cas_cache/disk.h
+++ b/modules/cas_cache/disk.h
@@ -31,7 +31,6 @@ struct cas_disk {
 	struct cas_exp_obj *exp_obj;
 
 	struct kobject kobj;
-	struct list_head list;
 
 	void *private;
 };
@@ -49,15 +48,6 @@ int cas_disk_allocate_minors(int count);
  */
 struct cas_disk *cas_disk_open(const char *path, void *private);
 
-/**
- * @brief Claim previously opened block device
- * @param path Path to block device
- * @param private Private data
- * @return Pointer to cas_disk structure related to block device, or NULL
- *	if device is not opened.
- */
-struct cas_disk *cas_disk_claim(const char *path, void *private);
-
 /**
  * @brief Close block device and remove from cas
  * @param dsk Pointer to cas_disk structure related to block device
diff --git a/modules/cas_cache/exp_obj.c b/modules/cas_cache/exp_obj.c
index 4d2895f..07954f3 100644
--- a/modules/cas_cache/exp_obj.c
+++ b/modules/cas_cache/exp_obj.c
@@ -407,7 +407,7 @@ static int _cas_init_tag_set(struct cas_disk *dsk, struct blk_mq_tag_set *set)
 }
 
 int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
-			struct module *owner, struct cas_exp_obj_ops *ops)
+		struct module *owner, struct cas_exp_obj_ops *ops, void *priv)
 {
 	struct cas_exp_obj *exp_obj;
 	struct request_queue *queue;
@@ -469,6 +469,8 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 	queue->queuedata = dsk;
 	exp_obj->queue = queue;
 
+	dsk->private = priv;
+
 	_cas_init_queues(dsk);
 
 	gd->fops = &_cas_exp_obj_ops;
@@ -486,6 +488,7 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 	return 0;
 
 error_set_geometry:
+	dsk->private = NULL;
 	_cas_exp_obj_clear_dev_t(dsk);
 error_exp_obj_set_dev_t:
 	cas_cleanup_mq_disk(exp_obj);
diff --git a/modules/cas_cache/exp_obj.h b/modules/cas_cache/exp_obj.h
index dfe4ecc..58843b0 100644
--- a/modules/cas_cache/exp_obj.h
+++ b/modules/cas_cache/exp_obj.h
@@ -56,10 +56,11 @@ void cas_exp_obj_free(struct cas_disk *dsk);
  * @param dev_name Name of exported object (top device)
  * @param owner Pointer to cas module
  * @param ops Pointer to structure with callback functions
+ * @param priv Private data
  * @return 0 if success, errno if failure
  */
 int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
-			struct module *owner, struct cas_exp_obj_ops *ops);
+		struct module *owner, struct cas_exp_obj_ops *ops, void *priv);
 
 /**
  * @brief Get request queue of exported object (top) block device
diff --git a/modules/cas_cache/volume/vol_block_dev_top.c b/modules/cas_cache/volume/vol_block_dev_top.c
index c265742..679d880 100644
--- a/modules/cas_cache/volume/vol_block_dev_top.c
+++ b/modules/cas_cache/volume/vol_block_dev_top.c
@@ -533,17 +533,9 @@ static int kcas_volume_create_exported_object(ocf_volume_t volume,
 		const char *name, void *priv, struct cas_exp_obj_ops *ops)
 {
 	struct bd_object *bvol = bd_object(volume);
-	const struct ocf_volume_uuid *uuid = ocf_volume_get_uuid(volume);
 	char dev_name[DISK_NAME_LEN];
-	struct cas_disk *dsk;
 	int result;
 
-	dsk = cas_disk_claim(uuid->data, priv);
-	if (dsk != bvol->dsk) {
-		result = -KCAS_ERR_SYSTEM;
-		goto end;
-	}
-
 	bvol->expobj_wq = alloc_workqueue("expobj_wq_%s",
 			WQ_MEM_RECLAIM | WQ_HIGHPRI, 0,
 			name);
@@ -552,8 +544,8 @@ static int kcas_volume_create_exported_object(ocf_volume_t volume,
 		goto end;
 	}
 
-	result = cas_exp_obj_create(dsk, name,
-			THIS_MODULE, ops);
+	result = cas_exp_obj_create(bvol->dsk, name,
+			THIS_MODULE, ops, priv);
 	if (result) {
 		destroy_workqueue(bvol->expobj_wq);
 		goto end;

From 8945b482cedb2b8d7abc7c403d2d9adc7a832d6e Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 18:31:22 +0200
Subject: [PATCH 02/11] Remove private parameter from cas_disk_open()

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/disk.c                        | 4 +---
 modules/cas_cache/disk.h                        | 3 +--
 modules/cas_cache/volume/vol_block_dev_bottom.c | 2 +-
 3 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/modules/cas_cache/disk.c b/modules/cas_cache/disk.c
index 75ca842..81b8f5e 100644
--- a/modules/cas_cache/disk.c
+++ b/modules/cas_cache/disk.c
@@ -96,7 +96,7 @@ static int _cas_disk_init_kobject(struct cas_disk *dsk)
 	return result;
 }
 
-struct cas_disk *cas_disk_open(const char *path, void *private)
+struct cas_disk *cas_disk_open(const char *path)
 {
 	struct cas_disk *dsk;
 	int result = 0;
@@ -127,8 +127,6 @@ struct cas_disk *cas_disk_open(const char *path, void *private)
 		goto error_open_bdev;
 	}
 
-	dsk->private = private;
-
 	dsk->id = cas_module.next_disk_id++;
 
 	result = _cas_disk_init_kobject(dsk);
diff --git a/modules/cas_cache/disk.h b/modules/cas_cache/disk.h
index 475b11a..b554e9d 100644
--- a/modules/cas_cache/disk.h
+++ b/modules/cas_cache/disk.h
@@ -43,10 +43,9 @@ int cas_disk_allocate_minors(int count);
 /**
  * @brief Open block device
  * @param path Path to block device
- * @param private Private data
  * @return Pointer to cas_disk related to opened block device
  */
-struct cas_disk *cas_disk_open(const char *path, void *private);
+struct cas_disk *cas_disk_open(const char *path);
 
 /**
  * @brief Close block device and remove from cas
diff --git a/modules/cas_cache/volume/vol_block_dev_bottom.c b/modules/cas_cache/volume/vol_block_dev_bottom.c
index 528dd79..4321d26 100644
--- a/modules/cas_cache/volume/vol_block_dev_bottom.c
+++ b/modules/cas_cache/volume/vol_block_dev_bottom.c
@@ -35,7 +35,7 @@ int block_dev_open_object(ocf_volume_t vol, void *volume_params)
 		return 0;
 	}
 
-	dsk = cas_disk_open(uuid->data, NULL);
+	dsk = cas_disk_open(uuid->data);
 	if (IS_ERR_OR_NULL(dsk)) {
 		int error = PTR_ERR(dsk) ?: -EINVAL;
 

From 1fe83b49720c959f827d1ac23133b9f9c0c910b1 Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 21:21:22 +0200
Subject: [PATCH 03/11] Manage lifetime of exported object in top adapter

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/disk.c                     | 3 ++-
 modules/cas_cache/volume/vol_block_dev_top.c | 9 +++++++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/modules/cas_cache/disk.c b/modules/cas_cache/disk.c
index 81b8f5e..801572d 100644
--- a/modules/cas_cache/disk.c
+++ b/modules/cas_cache/disk.c
@@ -149,9 +149,10 @@ error_kmem:
 
 static void __cas_disk_close(struct cas_disk *dsk)
 {
+	BUG_ON(dsk->exp_obj);
+
 	close_bdev_exclusive(dsk->bd, CAS_DISK_OPEN_FMODE);
 
-	cas_exp_obj_free(dsk);
 	kobject_put(&dsk->kobj);
 }
 
diff --git a/modules/cas_cache/volume/vol_block_dev_top.c b/modules/cas_cache/volume/vol_block_dev_top.c
index 679d880..184ce6f 100644
--- a/modules/cas_cache/volume/vol_block_dev_top.c
+++ b/modules/cas_cache/volume/vol_block_dev_top.c
@@ -582,12 +582,17 @@ static int kcas_volume_destroy_exported_object(ocf_volume_t volume)
 
 	result = cas_exp_obj_destroy(bvol->dsk);
 	if (result)
-		goto out;
+		goto err;
 
 	bvol->expobj_valid = false;
 	destroy_workqueue(bvol->expobj_wq);
 
-out:
+	cas_exp_obj_unlock(bvol->dsk);
+	cas_exp_obj_free(bvol->dsk);
+
+	return 0;
+
+err:
 	cas_exp_obj_unlock(bvol->dsk);
 
 	return result;

From ad783917d024a3c6d41bb30207e5eff7c4c6a722 Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 21:28:57 +0200
Subject: [PATCH 04/11] Remove one-liner helper functions

Those were not very helpful. Mostly made the code harder to read.

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/exp_obj.c | 17 ++---------------
 1 file changed, 2 insertions(+), 15 deletions(-)

diff --git a/modules/cas_cache/exp_obj.c b/modules/cas_cache/exp_obj.c
index 07954f3..78d554a 100644
--- a/modules/cas_cache/exp_obj.c
+++ b/modules/cas_cache/exp_obj.c
@@ -66,12 +66,6 @@ void cas_deinit_exp_objs(void)
 	kmem_cache_destroy(cas_module.exp_obj_cache);
 }
 
-static inline void _cas_exp_obj_handle_bio(struct cas_disk *dsk,
-					    struct bio *bio)
-{
-	dsk->exp_obj->ops->submit_bio(dsk, bio, dsk->private);
-}
-
 static MAKE_RQ_RET_TYPE _cas_exp_obj_submit_bio(struct bio *bio)
 {
 	struct cas_disk *dsk;
@@ -79,7 +73,7 @@ static MAKE_RQ_RET_TYPE _cas_exp_obj_submit_bio(struct bio *bio)
 	BUG_ON(!bio);
 	dsk = CAS_BIO_GET_GENDISK(bio)->private_data;
 
-	_cas_exp_obj_handle_bio(dsk, bio);
+	dsk->exp_obj->ops->submit_bio(dsk, bio, dsk->private);
 
 	KRETURN(0);
 }
@@ -320,7 +314,6 @@ static void __cas_exp_obj_release(struct cas_exp_obj *exp_obj)
 {
 	kmem_cache_free(cas_module.exp_obj_cache, exp_obj);
 }
-
 static void _cas_exp_obj_release(struct kobject *kobj)
 {
 	struct cas_exp_obj *exp_obj;
@@ -593,12 +586,6 @@ error_bd_claim:
 	return result;
 }
 
-bool cas_exp_obj_activated(struct cas_disk *dsk)
-{
-	BUG_ON(!dsk);
-	return dsk->exp_obj->activated;
-}
-
 int cas_exp_obj_lock(struct cas_disk *dsk)
 {
 	struct cas_exp_obj *exp_obj;
@@ -647,7 +634,7 @@ int cas_exp_obj_destroy(struct cas_disk *dsk)
 
 	exp_obj = dsk->exp_obj;
 
-	if (cas_exp_obj_activated(dsk)) {
+	if (dsk->exp_obj->activated) {
 		sysfs_remove_link(&exp_obj->kobj, "blockdev");
 		bd_release_from_disk(dsk->bd, exp_obj->gd);
 		_cas_exp_obj_clear_dev_t(dsk);

From 2f54aea87dad6ff819fbb6b5228718fb2aa43e90 Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 22:38:10 +0200
Subject: [PATCH 05/11] Remove exported object kobj

Simplify exported object lifecycle.

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/exp_obj.c                  | 181 +++++++------------
 modules/cas_cache/exp_obj.h                  |   4 +-
 modules/cas_cache/volume/vol_block_dev_top.c |   8 +-
 3 files changed, 69 insertions(+), 124 deletions(-)

diff --git a/modules/cas_cache/exp_obj.c b/modules/cas_cache/exp_obj.c
index 78d554a..694182e 100644
--- a/modules/cas_cache/exp_obj.c
+++ b/modules/cas_cache/exp_obj.c
@@ -19,11 +19,6 @@
 #define CAS_DEV_MINORS 16
 #define KMEM_CACHE_MIN_SIZE sizeof(void *)
 
-static inline struct cas_exp_obj *cas_kobj_to_exp_obj(struct kobject *kobj)
-{
-	return container_of(kobj, struct cas_exp_obj, kobj);
-}
-
 static inline int bd_claim_by_disk(struct block_device *bdev, void *holder,
 				   struct gendisk *disk)
 {
@@ -295,64 +290,15 @@ static int cas_exp_obj_alloc(struct cas_disk *dsk)
 	return 0;
 }
 
-void cas_exp_obj_free(struct cas_disk *dsk)
+static void cas_exp_obj_free(struct cas_disk *dsk)
 {
-	struct cas_exp_obj *exp_obj;
-
-	CAS_DEBUG_DISK_TRACE(dsk);
-
-	exp_obj = dsk->exp_obj;
-
-	if (!exp_obj)
+	if (!dsk->exp_obj)
 		return;
 
-	kobject_put(&exp_obj->kobj);
+	kmem_cache_free(cas_module.exp_obj_cache, dsk->exp_obj);
 	dsk->exp_obj = NULL;
 }
 
-static void __cas_exp_obj_release(struct cas_exp_obj *exp_obj)
-{
-	kmem_cache_free(cas_module.exp_obj_cache, exp_obj);
-}
-static void _cas_exp_obj_release(struct kobject *kobj)
-{
-	struct cas_exp_obj *exp_obj;
-	struct module *owner;
-
-	BUG_ON(!kobj);
-
-	exp_obj = cas_kobj_to_exp_obj(kobj);
-	BUG_ON(!exp_obj);
-
-	CAS_DEBUG_TRACE();
-
-	owner = exp_obj->owner;
-
-	kfree(exp_obj->dev_name);
-	__cas_exp_obj_release(exp_obj);
-
-	if (owner)
-		module_put(owner);
-}
-
-static struct kobj_type cas_exp_obj_ktype = {
-	.release = _cas_exp_obj_release
-};
-
-static int _cas_exp_obj_init_kobject(struct cas_disk *dsk)
-{
-	int result = 0;
-	struct cas_exp_obj *exp_obj = dsk->exp_obj;
-
-	kobject_init(&exp_obj->kobj, &cas_exp_obj_ktype);
-	result = kobject_add(&exp_obj->kobj, &dsk->kobj,
-			     "%s", exp_obj->dev_name);
-	if (result)
-		CAS_DEBUG_DISK_ERROR(dsk, "Cannot register kobject");
-
-	return result;
-}
-
 static CAS_BLK_STATUS_T _cas_exp_obj_queue_rq(struct blk_mq_hw_ctx *hctx,
 		const struct blk_mq_queue_data *bd)
 {
@@ -437,11 +383,6 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 	exp_obj->owner = owner;
 	exp_obj->ops = ops;
 
-	result = _cas_exp_obj_init_kobject(dsk);
-	if (result) {
-		goto error_init_kobject;
-	}
-
 	result = _cas_init_tag_set(dsk, &dsk->tag_set);
 	if (result) {
 		goto error_init_tag_set;
@@ -489,36 +430,17 @@ error_exp_obj_set_dev_t:
 error_alloc_mq_disk:
 	blk_mq_free_tag_set(&dsk->tag_set);
 error_init_tag_set:
-	kobject_put(&exp_obj->kobj);
-	/* kobject put does all the cleanup below internally */
-	return result;
-error_init_kobject:
 	module_put(owner);
 	dsk->exp_obj->owner = NULL;
 error_module_get:
 	kfree(exp_obj->dev_name);
 error_kstrdup:
-	__cas_exp_obj_release(exp_obj);
-	dsk->exp_obj = NULL;
+	cas_exp_obj_free(dsk);
 error_exp_obj_alloc:
 	return result;
 
 }
 
-struct request_queue *cas_exp_obj_get_queue(struct cas_disk *dsk)
-{
-	BUG_ON(!dsk);
-	BUG_ON(!dsk->exp_obj);
-	return dsk->exp_obj->queue;
-}
-
-struct gendisk *cas_exp_obj_get_gendisk(struct cas_disk *dsk)
-{
-	BUG_ON(!dsk);
-	BUG_ON(!dsk->exp_obj);
-	return dsk->exp_obj->gd;
-}
-
 static bool _cas_exp_obj_exists(const char *path)
 {
 	struct file *exported;
@@ -568,24 +490,66 @@ int cas_exp_obj_activate(struct cas_disk *dsk)
 	if (result)
 		goto error_bd_claim;
 
-	result = sysfs_create_link(&dsk->exp_obj->kobj,
-				   &disk_to_dev(dsk->exp_obj->gd)->kobj,
-				   "blockdev");
-	if (result)
-		goto error_sysfs_link;
-
 	CAS_DEBUG_DISK(dsk, "Activated exp object %s", dsk->exp_obj->dev_name);
 
 	return 0;
 
-error_sysfs_link:
-	bd_release_from_disk(dsk->bd, dsk->exp_obj->gd);
 error_bd_claim:
 	del_gendisk(dsk->exp_obj->gd);
 	dsk->exp_obj->activated = false;
 	return result;
 }
 
+int cas_exp_obj_destroy(struct cas_disk *dsk)
+{
+	struct cas_exp_obj *exp_obj;
+
+	BUG_ON(!dsk);
+
+	if (!dsk->exp_obj)
+		return -ENODEV;
+
+	CAS_DEBUG_DISK_TRACE(dsk);
+
+	exp_obj = dsk->exp_obj;
+
+	if (dsk->exp_obj->activated) {
+		bd_release_from_disk(dsk->bd, exp_obj->gd);
+		_cas_exp_obj_clear_dev_t(dsk);
+		del_gendisk(exp_obj->gd);
+	}
+
+	if (exp_obj->queue)
+		blk_cleanup_queue(exp_obj->queue);
+
+	blk_mq_free_tag_set(&dsk->tag_set);
+
+	put_disk(exp_obj->gd);
+
+	return 0;
+}
+
+void cas_exp_obj_cleanup(struct cas_disk *dsk)
+{
+	struct cas_exp_obj *exp_obj;
+	struct module *owner;
+
+	CAS_DEBUG_DISK_TRACE(dsk);
+
+	exp_obj = dsk->exp_obj;
+
+	if (!exp_obj)
+		return;
+
+	owner = exp_obj->owner;
+
+	kfree(exp_obj->dev_name);
+	cas_exp_obj_free(dsk);
+
+	if (owner)
+		module_put(owner);
+}
+
 int cas_exp_obj_lock(struct cas_disk *dsk)
 {
 	struct cas_exp_obj *exp_obj;
@@ -621,33 +585,16 @@ int cas_exp_obj_unlock(struct cas_disk *dsk)
 	return 0;
 }
 
-int cas_exp_obj_destroy(struct cas_disk *dsk)
+struct request_queue *cas_exp_obj_get_queue(struct cas_disk *dsk)
 {
-	struct cas_exp_obj *exp_obj;
-
 	BUG_ON(!dsk);
-
-	if (!dsk->exp_obj)
-		return -ENODEV;
-
-	CAS_DEBUG_DISK_TRACE(dsk);
-
-	exp_obj = dsk->exp_obj;
-
-	if (dsk->exp_obj->activated) {
-		sysfs_remove_link(&exp_obj->kobj, "blockdev");
-		bd_release_from_disk(dsk->bd, exp_obj->gd);
-		_cas_exp_obj_clear_dev_t(dsk);
-		del_gendisk(exp_obj->gd);
-	}
-
-	if (exp_obj->queue)
-		blk_cleanup_queue(exp_obj->queue);
-
-	blk_mq_free_tag_set(&dsk->tag_set);
-
-	put_disk(exp_obj->gd);
-
-	return 0;
-
+	BUG_ON(!dsk->exp_obj);
+	return dsk->exp_obj->queue;
+}
+
+struct gendisk *cas_exp_obj_get_gendisk(struct cas_disk *dsk)
+{
+	BUG_ON(!dsk);
+	BUG_ON(!dsk->exp_obj);
+	return dsk->exp_obj->gd;
 }
diff --git a/modules/cas_cache/exp_obj.h b/modules/cas_cache/exp_obj.h
index 58843b0..cf2c24b 100644
--- a/modules/cas_cache/exp_obj.h
+++ b/modules/cas_cache/exp_obj.h
@@ -5,7 +5,6 @@
 #ifndef __CASDISK_EXP_OBJ_H__
 #define __CASDISK_EXP_OBJ_H__
 
-#include <linux/kobject.h>
 #include <linux/fs.h>
 
 struct cas_disk;
@@ -39,7 +38,6 @@ struct cas_exp_obj {
 	struct cas_exp_obj_ops *ops;
 
 	const char *dev_name;
-	struct kobject kobj;
 
 	atomic_t pt_ios;
 	atomic_t *pending_rqs;
@@ -48,7 +46,7 @@ struct cas_exp_obj {
 int __init cas_init_exp_objs(void);
 void cas_deinit_exp_objs(void);
 
-void cas_exp_obj_free(struct cas_disk *dsk);
+void cas_exp_obj_cleanup(struct cas_disk *dsk);
 
 /**
  * @brief Create exported object (top device)
diff --git a/modules/cas_cache/volume/vol_block_dev_top.c b/modules/cas_cache/volume/vol_block_dev_top.c
index 184ce6f..eb92efa 100644
--- a/modules/cas_cache/volume/vol_block_dev_top.c
+++ b/modules/cas_cache/volume/vol_block_dev_top.c
@@ -588,7 +588,7 @@ static int kcas_volume_destroy_exported_object(ocf_volume_t volume)
 	destroy_workqueue(bvol->expobj_wq);
 
 	cas_exp_obj_unlock(bvol->dsk);
-	cas_exp_obj_free(bvol->dsk);
+	cas_exp_obj_cleanup(bvol->dsk);
 
 	return 0;
 
@@ -759,11 +759,11 @@ static int kcas_core_stop_exported_object(ocf_core_t core, void *cntx)
 	return 0;
 }
 
-static int kcas_core_free_exported_object(ocf_core_t core, void *cntx)
+static int kcas_core_cleanup_exported_object(ocf_core_t core, void *cntx)
 {
 	struct bd_object *bvol = bd_object(ocf_core_get_volume(core));
 
-	cas_exp_obj_free(bvol->dsk);
+	cas_exp_obj_cleanup(bvol->dsk);
 
 	return 0;
 }
@@ -783,7 +783,7 @@ int kcas_cache_destroy_all_core_exported_objects(ocf_cache_t cache)
 	}
 
 	ocf_core_visit(cache, kcas_core_stop_exported_object, NULL, true);
-	ocf_core_visit(cache, kcas_core_free_exported_object, NULL, true);
+	ocf_core_visit(cache, kcas_core_cleanup_exported_object, NULL, true);
 
 	return 0;
 }

From 67ed36ae0e47abe3274b9102e561f8f1c0f011bd Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 21:58:57 +0200
Subject: [PATCH 06/11] Remove disk kobj

Simplify disk life cycle.

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/cas_cache.h |  3 --
 modules/cas_cache/disk.c      | 62 +++--------------------------------
 modules/cas_cache/disk.h      |  4 ---
 3 files changed, 4 insertions(+), 65 deletions(-)

diff --git a/modules/cas_cache/cas_cache.h b/modules/cas_cache/cas_cache.h
index 14bd124..ac27681 100644
--- a/modules/cas_cache/cas_cache.h
+++ b/modules/cas_cache/cas_cache.h
@@ -51,14 +51,11 @@ enum {
 };
 
 struct cas_module {
-	uint32_t next_disk_id;
 	int disk_major;
 	int next_minor;
 
 	struct kmem_cache *disk_cache;
 	struct kmem_cache *exp_obj_cache;
-
-	struct kobject kobj;
 };
 
 extern struct cas_module cas_module;
diff --git a/modules/cas_cache/disk.c b/modules/cas_cache/disk.c
index 801572d..9ec7b4a 100644
--- a/modules/cas_cache/disk.c
+++ b/modules/cas_cache/disk.c
@@ -13,11 +13,6 @@
 
 #define CAS_DISK_OPEN_FMODE (FMODE_READ | FMODE_WRITE)
 
-static inline struct cas_disk *cas_kobj_to_disk(struct kobject *kobj)
-{
-	return container_of(kobj, struct cas_disk, kobj);
-}
-
 static inline struct block_device *open_bdev_exclusive(const char *path,
 						       fmode_t mode,
 						       void *holder)
@@ -30,32 +25,10 @@ static inline void close_bdev_exclusive(struct block_device *bdev, fmode_t mode)
 	blkdev_put(bdev, mode | FMODE_EXCL);
 }
 
-static void _cas_disk_release(struct kobject *kobj)
-{
-	struct cas_disk *dsk;
-
-	BUG_ON(!kobj);
-
-	dsk = cas_kobj_to_disk(kobj);
-	BUG_ON(!dsk);
-
-	CAS_DEBUG_DISK_TRACE(dsk);
-
-	kfree(dsk->path);
-
-	kmem_cache_free(cas_module.disk_cache, dsk);
-}
-
-static struct kobj_type cas_disk_ktype = {
-	.release = _cas_disk_release,
-};
-
 int __init cas_init_disks(void)
 {
 	CAS_DEBUG_TRACE();
 
-	cas_module.next_disk_id = 1;
-
 	cas_module.disk_major = register_blkdev(cas_module.disk_major,
 						  "cas");
 	if (cas_module.disk_major <= 0) {
@@ -83,19 +56,6 @@ void cas_deinit_disks(void)
 	unregister_blkdev(cas_module.disk_major, "cas");
 }
 
-static int _cas_disk_init_kobject(struct cas_disk *dsk)
-{
-	int result = 0;
-
-	kobject_init(&dsk->kobj, &cas_disk_ktype);
-	result = kobject_add(&dsk->kobj, &disk_to_dev(dsk->bd->bd_disk)->kobj,
-			     "cas%d", dsk->id);
-	if (result)
-		CAS_DEBUG_DISK_ERROR(dsk, "Cannot register kobject");
-
-	return result;
-}
-
 struct cas_disk *cas_disk_open(const char *path)
 {
 	struct cas_disk *dsk;
@@ -127,18 +87,10 @@ struct cas_disk *cas_disk_open(const char *path)
 		goto error_open_bdev;
 	}
 
-	dsk->id = cas_module.next_disk_id++;
-
-	result = _cas_disk_init_kobject(dsk);
-	if (result)
-		goto error_kobject;
-
 	CAS_DEBUG_DISK(dsk, "Created (%p)", dsk);
 
 	return dsk;
 
-error_kobject:
-	close_bdev_exclusive(dsk->bd, CAS_DISK_OPEN_FMODE);
 error_open_bdev:
 	kfree(dsk->path);
 error_kstrdup:
@@ -147,15 +99,6 @@ error_kmem:
 	return ERR_PTR(result);
 }
 
-static void __cas_disk_close(struct cas_disk *dsk)
-{
-	BUG_ON(dsk->exp_obj);
-
-	close_bdev_exclusive(dsk->bd, CAS_DISK_OPEN_FMODE);
-
-	kobject_put(&dsk->kobj);
-}
-
 void cas_disk_close(struct cas_disk *dsk)
 {
 	BUG_ON(!dsk);
@@ -163,7 +106,10 @@ void cas_disk_close(struct cas_disk *dsk)
 
 	CAS_DEBUG_DISK(dsk, "Destroying (%p)", dsk);
 
-	__cas_disk_close(dsk);
+	close_bdev_exclusive(dsk->bd, CAS_DISK_OPEN_FMODE);
+
+	kfree(dsk->path);
+	kmem_cache_free(cas_module.disk_cache, dsk);
 }
 
 struct block_device *cas_disk_get_blkdev(struct cas_disk *dsk)
diff --git a/modules/cas_cache/disk.h b/modules/cas_cache/disk.h
index b554e9d..80c7e3a 100644
--- a/modules/cas_cache/disk.h
+++ b/modules/cas_cache/disk.h
@@ -5,7 +5,6 @@
 #ifndef __CASDISK_DISK_H__
 #define __CASDISK_DISK_H__
 
-#include <linux/kobject.h>
 #include <linux/fs.h>
 #include <linux/blkdev.h>
 #include <linux/mutex.h>
@@ -15,7 +14,6 @@
 struct cas_exp_obj;
 
 struct cas_disk {
-	uint32_t id;
 	char *path;
 
 	struct mutex openers_lock;
@@ -30,8 +28,6 @@ struct cas_disk {
 	struct blk_mq_tag_set tag_set;
 	struct cas_exp_obj *exp_obj;
 
-	struct kobject kobj;
-
 	void *private;
 };
 

From 72cf855355747489688c9c70eda038a7205d7467 Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 22:09:08 +0200
Subject: [PATCH 07/11] Move openers_lock to struct cas_exp_obj

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/disk.c    |  2 --
 modules/cas_cache/disk.h    |  4 ----
 modules/cas_cache/exp_obj.c | 40 ++++++++++++++++++++++---------------
 modules/cas_cache/exp_obj.h |  4 ++++
 4 files changed, 28 insertions(+), 22 deletions(-)

diff --git a/modules/cas_cache/disk.c b/modules/cas_cache/disk.c
index 9ec7b4a..8ca6056 100644
--- a/modules/cas_cache/disk.c
+++ b/modules/cas_cache/disk.c
@@ -72,8 +72,6 @@ struct cas_disk *cas_disk_open(const char *path)
 		goto error_kmem;
 	}
 
-	mutex_init(&dsk->openers_lock);
-
 	dsk->path = kstrdup(path, GFP_KERNEL);
 	if (!dsk->path) {
 		result = -ENOMEM;
diff --git a/modules/cas_cache/disk.h b/modules/cas_cache/disk.h
index 80c7e3a..7ba1257 100644
--- a/modules/cas_cache/disk.h
+++ b/modules/cas_cache/disk.h
@@ -16,10 +16,6 @@ struct cas_exp_obj;
 struct cas_disk {
 	char *path;
 
-	struct mutex openers_lock;
-	unsigned int openers;
-	bool claimed;
-
 	struct block_device *bd;
 
 	int gd_flags;
diff --git a/modules/cas_cache/exp_obj.c b/modules/cas_cache/exp_obj.c
index 694182e..c08b70f 100644
--- a/modules/cas_cache/exp_obj.c
+++ b/modules/cas_cache/exp_obj.c
@@ -234,32 +234,34 @@ static void _cas_exp_obj_clear_dev_t(struct cas_disk *dsk)
 static int _cas_exp_obj_open(struct block_device *bdev, fmode_t mode)
 {
 	struct cas_disk *dsk = bdev->bd_disk->private_data;
+	struct cas_exp_obj *exp_obj = dsk->exp_obj;
 	int result = -ENAVAIL;
 
-	mutex_lock(&dsk->openers_lock);
+	mutex_lock(&exp_obj->openers_lock);
 
-	if (!dsk->claimed) {
-		if (unlikely(dsk->openers == UINT_MAX)) {
+	if (!exp_obj->claimed) {
+		if (unlikely(exp_obj->openers == UINT_MAX)) {
 			result = -EBUSY;
 		} else {
-			dsk->openers++;
+			exp_obj->openers++;
 			result = 0;
 		}
 	}
 
-	mutex_unlock(&dsk->openers_lock);
+	mutex_unlock(&dsk->exp_obj->openers_lock);
 	return result;
 }
 
 static void _cas_exp_obj_close(struct gendisk *gd, fmode_t mode)
 {
 	struct cas_disk *dsk = gd->private_data;
+	struct cas_exp_obj *exp_obj = dsk->exp_obj;
 
-	BUG_ON(dsk->openers == 0);
+	BUG_ON(exp_obj->openers == 0);
 
-	mutex_lock(&dsk->openers_lock);
-	dsk->openers--;
-	mutex_unlock(&dsk->openers_lock);
+	mutex_lock(&exp_obj->openers_lock);
+	exp_obj->openers--;
+	mutex_unlock(&exp_obj->openers_lock);
 
 }
 
@@ -369,6 +371,8 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 
 	exp_obj = dsk->exp_obj;
 
+	mutex_init(&exp_obj->openers_lock);
+
 	exp_obj->dev_name = kstrdup(dev_name, GFP_KERNEL);
 	if (!exp_obj->dev_name) {
 		result = -ENOMEM;
@@ -562,25 +566,29 @@ int cas_exp_obj_lock(struct cas_disk *dsk)
 
 	exp_obj = dsk->exp_obj;
 
-	mutex_lock(&dsk->openers_lock);
+	mutex_lock(&exp_obj->openers_lock);
 
-	if (dsk->openers == 0) {
-		dsk->claimed = true;
+	if (exp_obj->openers == 0) {
+		exp_obj->claimed = true;
 		result = 0;
 	}
 
-	mutex_unlock(&dsk->openers_lock);
+	mutex_unlock(&exp_obj->openers_lock);
 	return result;
 }
 
 int cas_exp_obj_unlock(struct cas_disk *dsk)
 {
+	struct cas_exp_obj *exp_obj;
+
 	BUG_ON(!dsk);
 	CAS_DEBUG_DISK_TRACE(dsk);
 
-	mutex_lock(&dsk->openers_lock);
-	dsk->claimed = false;
-	mutex_unlock(&dsk->openers_lock);
+	exp_obj = dsk->exp_obj;
+
+	mutex_lock(&exp_obj->openers_lock);
+	exp_obj->claimed = false;
+	mutex_unlock(&exp_obj->openers_lock);
 
 	return 0;
 }
diff --git a/modules/cas_cache/exp_obj.h b/modules/cas_cache/exp_obj.h
index cf2c24b..2a280fc 100644
--- a/modules/cas_cache/exp_obj.h
+++ b/modules/cas_cache/exp_obj.h
@@ -39,6 +39,10 @@ struct cas_exp_obj {
 
 	const char *dev_name;
 
+	struct mutex openers_lock;
+	unsigned int openers;
+	bool claimed;
+
 	atomic_t pt_ios;
 	atomic_t *pending_rqs;
 };

From dc390adf49d48318c2004344fb6ae19b690a53e9 Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 22:18:57 +0200
Subject: [PATCH 08/11] Move exported object specific properties to struct
 cas_exp_obj

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/disk.h    |  4 ----
 modules/cas_cache/exp_obj.c | 21 ++++++++++++---------
 modules/cas_cache/exp_obj.h |  5 +++++
 3 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/modules/cas_cache/disk.h b/modules/cas_cache/disk.h
index 7ba1257..4b8dd33 100644
--- a/modules/cas_cache/disk.h
+++ b/modules/cas_cache/disk.h
@@ -18,10 +18,6 @@ struct cas_disk {
 
 	struct block_device *bd;
 
-	int gd_flags;
-	int gd_minors;
-
-	struct blk_mq_tag_set tag_set;
 	struct cas_exp_obj *exp_obj;
 
 	void *private;
diff --git a/modules/cas_cache/exp_obj.c b/modules/cas_cache/exp_obj.c
index c08b70f..453ddf3 100644
--- a/modules/cas_cache/exp_obj.c
+++ b/modules/cas_cache/exp_obj.c
@@ -156,6 +156,7 @@ static int _cas_flags = GENHD_FL_EXT_DEVT;
 
 static int _cas_exp_obj_hide_parts(struct cas_disk *dsk)
 {
+	struct cas_exp_obj *exp_obj = dsk->exp_obj;
 	struct block_device *bd = cas_disk_get_blkdev(dsk);
 	struct gendisk *gdsk = cas_disk_get_gendisk(dsk);
 
@@ -175,8 +176,8 @@ static int _cas_exp_obj_hide_parts(struct cas_disk *dsk)
 	}
 
 	/* Save original flags and minors */
-	dsk->gd_flags = gdsk->flags & _cas_flags;
-	dsk->gd_minors = gdsk->minors;
+	exp_obj->gd_flags = gdsk->flags & _cas_flags;
+	exp_obj->gd_minors = gdsk->minors;
 
 	/* Setup disk of bottom device as not partitioned device */
 	gdsk->flags &= ~_cas_flags;
@@ -189,6 +190,7 @@ static int _cas_exp_obj_hide_parts(struct cas_disk *dsk)
 
 static int _cas_exp_obj_set_dev_t(struct cas_disk *dsk, struct gendisk *gd)
 {
+	struct cas_exp_obj *exp_obj = dsk->exp_obj;
 	int flags;
 	int minors = disk_max_parts(cas_disk_get_gendisk(dsk));
 	struct block_device *bdev;
@@ -202,7 +204,7 @@ static int _cas_exp_obj_set_dev_t(struct cas_disk *dsk, struct gendisk *gd)
 	} else {
 		if (_cas_exp_obj_hide_parts(dsk))
 			return -EINVAL;
-		flags = dsk->gd_flags;
+		flags = exp_obj->gd_flags;
 	}
 
 	gd->first_minor = cas_disk_allocate_minors(minors);
@@ -220,13 +222,14 @@ static int _cas_exp_obj_set_dev_t(struct cas_disk *dsk, struct gendisk *gd)
 
 static void _cas_exp_obj_clear_dev_t(struct cas_disk *dsk)
 {
+	struct cas_exp_obj *exp_obj = dsk->exp_obj;
 	struct block_device *bdev = cas_disk_get_blkdev(dsk);
 	struct gendisk *gdsk = cas_disk_get_gendisk(dsk);
 
 	if (cas_bdev_whole(bdev) == bdev) {
 		/* Restore previous configuration of bottom disk */
-		gdsk->minors = dsk->gd_minors;
-		gdsk->flags |= dsk->gd_flags;
+		gdsk->minors = exp_obj->gd_minors;
+		gdsk->flags |= exp_obj->gd_flags;
 		cas_reread_partitions(bdev);
 	}
 }
@@ -387,12 +390,12 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 	exp_obj->owner = owner;
 	exp_obj->ops = ops;
 
-	result = _cas_init_tag_set(dsk, &dsk->tag_set);
+	result = _cas_init_tag_set(dsk, &exp_obj->tag_set);
 	if (result) {
 		goto error_init_tag_set;
 	}
 
-	result = cas_alloc_mq_disk(&gd, &queue, &dsk->tag_set);
+	result = cas_alloc_mq_disk(&gd, &queue, &exp_obj->tag_set);
 	if (result) {
 		goto error_alloc_mq_disk;
 	}
@@ -432,7 +435,7 @@ error_exp_obj_set_dev_t:
 	cas_cleanup_mq_disk(exp_obj);
 	dsk->exp_obj->gd = NULL;
 error_alloc_mq_disk:
-	blk_mq_free_tag_set(&dsk->tag_set);
+	blk_mq_free_tag_set(&exp_obj->tag_set);
 error_init_tag_set:
 	module_put(owner);
 	dsk->exp_obj->owner = NULL;
@@ -526,7 +529,7 @@ int cas_exp_obj_destroy(struct cas_disk *dsk)
 	if (exp_obj->queue)
 		blk_cleanup_queue(exp_obj->queue);
 
-	blk_mq_free_tag_set(&dsk->tag_set);
+	blk_mq_free_tag_set(&exp_obj->tag_set);
 
 	put_disk(exp_obj->gd);
 
diff --git a/modules/cas_cache/exp_obj.h b/modules/cas_cache/exp_obj.h
index 2a280fc..0f046b2 100644
--- a/modules/cas_cache/exp_obj.h
+++ b/modules/cas_cache/exp_obj.h
@@ -43,6 +43,11 @@ struct cas_exp_obj {
 	unsigned int openers;
 	bool claimed;
 
+	int gd_flags;
+	int gd_minors;
+
+	struct blk_mq_tag_set tag_set;
+
 	atomic_t pt_ios;
 	atomic_t *pending_rqs;
 };

From 61dff1f6fda7f34f074f79102148bf19f6a41767 Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 22:22:18 +0200
Subject: [PATCH 09/11] Move private field to struct cas_exp_obj

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/disk.h    |  2 --
 modules/cas_cache/exp_obj.c | 10 ++++++----
 modules/cas_cache/exp_obj.h |  2 ++
 3 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/modules/cas_cache/disk.h b/modules/cas_cache/disk.h
index 4b8dd33..ce4ed64 100644
--- a/modules/cas_cache/disk.h
+++ b/modules/cas_cache/disk.h
@@ -19,8 +19,6 @@ struct cas_disk {
 	struct block_device *bd;
 
 	struct cas_exp_obj *exp_obj;
-
-	void *private;
 };
 
 int __init cas_init_disks(void);
diff --git a/modules/cas_cache/exp_obj.c b/modules/cas_cache/exp_obj.c
index 453ddf3..5d6ff6d 100644
--- a/modules/cas_cache/exp_obj.c
+++ b/modules/cas_cache/exp_obj.c
@@ -64,11 +64,13 @@ void cas_deinit_exp_objs(void)
 static MAKE_RQ_RET_TYPE _cas_exp_obj_submit_bio(struct bio *bio)
 {
 	struct cas_disk *dsk;
+	struct cas_exp_obj *exp_obj;
 
 	BUG_ON(!bio);
 	dsk = CAS_BIO_GET_GENDISK(bio)->private_data;
+	exp_obj = dsk->exp_obj;
 
-	dsk->exp_obj->ops->submit_bio(dsk, bio, dsk->private);
+	exp_obj->ops->submit_bio(dsk, bio, exp_obj->private);
 
 	KRETURN(0);
 }
@@ -410,7 +412,7 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 	queue->queuedata = dsk;
 	exp_obj->queue = queue;
 
-	dsk->private = priv;
+	exp_obj->private = priv;
 
 	_cas_init_queues(dsk);
 
@@ -421,7 +423,7 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 	cas_blk_queue_make_request(queue, _cas_exp_obj_make_rq_fn);
 
 	if (exp_obj->ops->set_geometry) {
-		result = exp_obj->ops->set_geometry(dsk, dsk->private);
+		result = exp_obj->ops->set_geometry(dsk, exp_obj->private);
 		if (result)
 			goto error_set_geometry;
 	}
@@ -429,7 +431,7 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 	return 0;
 
 error_set_geometry:
-	dsk->private = NULL;
+	exp_obj->private = NULL;
 	_cas_exp_obj_clear_dev_t(dsk);
 error_exp_obj_set_dev_t:
 	cas_cleanup_mq_disk(exp_obj);
diff --git a/modules/cas_cache/exp_obj.h b/modules/cas_cache/exp_obj.h
index 0f046b2..d2e42d3 100644
--- a/modules/cas_cache/exp_obj.h
+++ b/modules/cas_cache/exp_obj.h
@@ -50,6 +50,8 @@ struct cas_exp_obj {
 
 	atomic_t pt_ios;
 	atomic_t *pending_rqs;
+
+	void *private;
 };
 
 int __init cas_init_exp_objs(void);

From d0d17545eb3f08d0473a2d450e5a47ff8a5d41a0 Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 22:29:09 +0200
Subject: [PATCH 10/11] Move major/minor management to exported object code

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/disk.c    | 25 +------------------------
 modules/cas_cache/disk.h    |  2 --
 modules/cas_cache/exp_obj.c | 27 +++++++++++++++++++++++++--
 3 files changed, 26 insertions(+), 28 deletions(-)

diff --git a/modules/cas_cache/disk.c b/modules/cas_cache/disk.c
index 8ca6056..1738802 100644
--- a/modules/cas_cache/disk.c
+++ b/modules/cas_cache/disk.c
@@ -29,21 +29,11 @@ int __init cas_init_disks(void)
 {
 	CAS_DEBUG_TRACE();
 
-	cas_module.disk_major = register_blkdev(cas_module.disk_major,
-						  "cas");
-	if (cas_module.disk_major <= 0) {
-		CAS_DEBUG_ERROR("Cannot allocate major number");
-		return -EINVAL;
-	}
-	CAS_DEBUG_PARAM("Allocated major number: %d", cas_module.disk_major);
-
 	cas_module.disk_cache =
 		kmem_cache_create("cas_disk", sizeof(struct cas_disk),
 				  0, 0, NULL);
-	if (!cas_module.disk_cache) {
-		unregister_blkdev(cas_module.disk_major, "cas");
+	if (!cas_module.disk_cache)
 		return -ENOMEM;
-	}
 
 	return 0;
 }
@@ -53,7 +43,6 @@ void cas_deinit_disks(void)
 	CAS_DEBUG_TRACE();
 
 	kmem_cache_destroy(cas_module.disk_cache);
-	unregister_blkdev(cas_module.disk_major, "cas");
 }
 
 struct cas_disk *cas_disk_open(const char *path)
@@ -129,15 +118,3 @@ struct request_queue *cas_disk_get_queue(struct cas_disk *dsk)
 	BUG_ON(!dsk->bd);
 	return cas_bdev_whole(dsk->bd)->bd_disk->queue;
 }
-
-int cas_disk_allocate_minors(int count)
-{
-	int minor = -1;
-
-	if (cas_module.next_minor + count <= (1 << MINORBITS)) {
-		minor = cas_module.next_minor;
-		cas_module.next_minor += count;
-	}
-
-	return minor;
-}
diff --git a/modules/cas_cache/disk.h b/modules/cas_cache/disk.h
index ce4ed64..7437673 100644
--- a/modules/cas_cache/disk.h
+++ b/modules/cas_cache/disk.h
@@ -24,8 +24,6 @@ struct cas_disk {
 int __init cas_init_disks(void);
 void cas_deinit_disks(void);
 
-int cas_disk_allocate_minors(int count);
-
 /**
  * @brief Open block device
  * @param path Path to block device
diff --git a/modules/cas_cache/exp_obj.c b/modules/cas_cache/exp_obj.c
index 5d6ff6d..0884a2b 100644
--- a/modules/cas_cache/exp_obj.c
+++ b/modules/cas_cache/exp_obj.c
@@ -46,10 +46,20 @@ int __init cas_init_exp_objs(void)
 {
 	CAS_DEBUG_TRACE();
 
+	cas_module.disk_major = register_blkdev(cas_module.disk_major,
+			"cas");
+	if (cas_module.disk_major <= 0) {
+		CAS_DEBUG_ERROR("Cannot allocate major number");
+		return -EINVAL;
+	}
+	CAS_DEBUG_PARAM("Allocated major number: %d", cas_module.disk_major);
+
 	cas_module.exp_obj_cache = kmem_cache_create("cas_exp_obj",
 			sizeof(struct cas_exp_obj), 0, 0, NULL);
-	if (!cas_module.exp_obj_cache)
+	if (!cas_module.exp_obj_cache) {
+		unregister_blkdev(cas_module.disk_major, "cas");
 		return -ENOMEM;
+	}
 
 	return 0;
 }
@@ -59,6 +69,7 @@ void cas_deinit_exp_objs(void)
 	CAS_DEBUG_TRACE();
 
 	kmem_cache_destroy(cas_module.exp_obj_cache);
+	unregister_blkdev(cas_module.disk_major, "cas");
 }
 
 static MAKE_RQ_RET_TYPE _cas_exp_obj_submit_bio(struct bio *bio)
@@ -190,6 +201,18 @@ static int _cas_exp_obj_hide_parts(struct cas_disk *dsk)
 	return 0;
 }
 
+static int _cas_exp_obj_allocate_minors(int count)
+{
+	int minor = -1;
+
+	if (cas_module.next_minor + count <= (1 << MINORBITS)) {
+		minor = cas_module.next_minor;
+		cas_module.next_minor += count;
+	}
+
+	return minor;
+}
+
 static int _cas_exp_obj_set_dev_t(struct cas_disk *dsk, struct gendisk *gd)
 {
 	struct cas_exp_obj *exp_obj = dsk->exp_obj;
@@ -209,7 +232,7 @@ static int _cas_exp_obj_set_dev_t(struct cas_disk *dsk, struct gendisk *gd)
 		flags = exp_obj->gd_flags;
 	}
 
-	gd->first_minor = cas_disk_allocate_minors(minors);
+	gd->first_minor = _cas_exp_obj_allocate_minors(minors);
 	if (gd->first_minor < 0) {
 		CAS_DEBUG_DISK_ERROR(dsk, "Cannot allocate %d minors", minors);
 		return -EINVAL;

From 5e2c1c15cfec6a5c7da26e92862fbb4708c0532e Mon Sep 17 00:00:00 2001
From: Robert Baldyga <robert.baldyga@intel.com>
Date: Fri, 16 Sep 2022 23:29:09 +0200
Subject: [PATCH 11/11] Merge exp obj create/activate

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
---
 modules/cas_cache/exp_obj.c                  | 117 ++++++++-----------
 modules/cas_cache/exp_obj.h                  |  10 --
 modules/cas_cache/layer_cache_management.c   |  12 --
 modules/cas_cache/volume/vol_block_dev_top.c |  46 --------
 modules/cas_cache/volume/vol_block_dev_top.h |   4 +-
 5 files changed, 52 insertions(+), 137 deletions(-)

diff --git a/modules/cas_cache/exp_obj.c b/modules/cas_cache/exp_obj.c
index 0884a2b..eff582b 100644
--- a/modules/cas_cache/exp_obj.c
+++ b/modules/cas_cache/exp_obj.c
@@ -375,6 +375,36 @@ static int _cas_init_tag_set(struct cas_disk *dsk, struct blk_mq_tag_set *set)
 	return blk_mq_alloc_tag_set(set);
 }
 
+static int _cas_exp_obj_check_path(const char *dev_name)
+{
+	struct file *exported;
+	char *path;
+	int result;
+
+	path = kmalloc(PATH_MAX, GFP_KERNEL);
+	if (!path)
+		return -ENOMEM;
+
+	snprintf(path, PATH_MAX, "/dev/%s", dev_name);
+
+	exported = filp_open(path, O_RDONLY, 0);
+
+	if (!IS_ERR_OR_NULL(exported)) {
+		filp_close(exported, NULL);
+		result = -EEXIST;
+
+	} else {
+		/* failed to open file - it is safe to assume,
+		 * it does not exist
+		 */
+		result = 0;
+	}
+
+	kfree(path);
+
+	return result;
+}
+
 int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 		struct module *owner, struct cas_exp_obj_ops *ops, void *priv)
 {
@@ -393,9 +423,18 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 	if (strlen(dev_name) >= DISK_NAME_LEN)
 		return -EINVAL;
 
+	result = _cas_exp_obj_check_path(dev_name);
+	if (result == -EEXIST) {
+		printk(KERN_ERR "Could not activate exported object, "
+				"because file /dev/%s exists.\n", dev_name);
+	}
+
+	if (result)
+		return result;
+
 	result = cas_exp_obj_alloc(dsk);
 	if (result)
-		goto error_exp_obj_alloc;
+		return result;
 
 	exp_obj = dsk->exp_obj;
 
@@ -451,8 +490,16 @@ int cas_exp_obj_create(struct cas_disk *dsk, const char *dev_name,
 			goto error_set_geometry;
 	}
 
+	add_disk(gd);
+
+	result = bd_claim_by_disk(dsk->bd, dsk, gd);
+	if (result)
+		goto error_bd_claim;
+
 	return 0;
 
+error_bd_claim:
+	del_gendisk(dsk->exp_obj->gd);
 error_set_geometry:
 	exp_obj->private = NULL;
 	_cas_exp_obj_clear_dev_t(dsk);
@@ -468,70 +515,10 @@ error_module_get:
 	kfree(exp_obj->dev_name);
 error_kstrdup:
 	cas_exp_obj_free(dsk);
-error_exp_obj_alloc:
 	return result;
 
 }
 
-static bool _cas_exp_obj_exists(const char *path)
-{
-	struct file *exported;
-
-	exported = filp_open(path, O_RDONLY, 0);
-
-	if (!exported || IS_ERR(exported)) {
-		/*failed to open file - it is safe to assume,
-		 * it does not exist
-		 */
-		return false;
-	}
-
-	filp_close(exported, NULL);
-	return true;
-}
-
-int cas_exp_obj_activate(struct cas_disk *dsk)
-{
-	char *path;
-	int result;
-
-	BUG_ON(!dsk);
-	BUG_ON(!dsk->exp_obj);
-	BUG_ON(!dsk->exp_obj->gd);
-	BUG_ON(dsk->exp_obj->activated);
-
-	CAS_DEBUG_DISK_TRACE(dsk);
-
-	path = kmalloc(PATH_MAX, GFP_KERNEL);
-	if (!path)
-		return -ENOMEM;
-
-	snprintf(path, PATH_MAX, "/dev/%s", dsk->exp_obj->dev_name);
-	if (_cas_exp_obj_exists(path)) {
-		printk(KERN_ERR "Could not activate exported object, "
-				"because file %s exists.\n", path);
-		kfree(path);
-		return -EEXIST;
-	}
-	kfree(path);
-
-	dsk->exp_obj->activated = true;
-	add_disk(dsk->exp_obj->gd);
-
-	result = bd_claim_by_disk(dsk->bd, dsk, dsk->exp_obj->gd);
-	if (result)
-		goto error_bd_claim;
-
-	CAS_DEBUG_DISK(dsk, "Activated exp object %s", dsk->exp_obj->dev_name);
-
-	return 0;
-
-error_bd_claim:
-	del_gendisk(dsk->exp_obj->gd);
-	dsk->exp_obj->activated = false;
-	return result;
-}
-
 int cas_exp_obj_destroy(struct cas_disk *dsk)
 {
 	struct cas_exp_obj *exp_obj;
@@ -545,11 +532,9 @@ int cas_exp_obj_destroy(struct cas_disk *dsk)
 
 	exp_obj = dsk->exp_obj;
 
-	if (dsk->exp_obj->activated) {
-		bd_release_from_disk(dsk->bd, exp_obj->gd);
-		_cas_exp_obj_clear_dev_t(dsk);
-		del_gendisk(exp_obj->gd);
-	}
+	bd_release_from_disk(dsk->bd, exp_obj->gd);
+	_cas_exp_obj_clear_dev_t(dsk);
+	del_gendisk(exp_obj->gd);
 
 	if (exp_obj->queue)
 		blk_cleanup_queue(exp_obj->queue);
diff --git a/modules/cas_cache/exp_obj.h b/modules/cas_cache/exp_obj.h
index d2e42d3..1c53657 100644
--- a/modules/cas_cache/exp_obj.h
+++ b/modules/cas_cache/exp_obj.h
@@ -33,8 +33,6 @@ struct cas_exp_obj {
 
 	struct module *owner;
 
-	bool activated;
-
 	struct cas_exp_obj_ops *ops;
 
 	const char *dev_name;
@@ -85,14 +83,6 @@ struct request_queue *cas_exp_obj_get_queue(struct cas_disk *dsk);
  */
 struct gendisk *cas_exp_obj_get_gendisk(struct cas_disk *dsk);
 
-/**
- * @brief Activate exported object (make it visible to OS
- *	and allow I/O handling)
- * @param dsk Pointer to cas_disk structure representing a block device
- * @return 0 if success, errno if failure
- */
-int cas_exp_obj_activate(struct cas_disk *dsk);
-
 /**
  * @brief Lock exported object
  * @param dsk Pointer to cas_disk structure representing a block device
diff --git a/modules/cas_cache/layer_cache_management.c b/modules/cas_cache/layer_cache_management.c
index c635d9b..4d8ccc3 100644
--- a/modules/cas_cache/layer_cache_management.c
+++ b/modules/cas_cache/layer_cache_management.c
@@ -1389,10 +1389,6 @@ int cache_mngt_add_core_to_cache(const char *cache_name, size_t name_len,
 	if (result)
 		goto error_after_add_core;
 
-	result = kcas_core_activate_exported_object(core);
-	if (result)
-		goto error_after_create_exported_object;
-
 	result = core_id_from_name(&core_id, cfg->name);
 	if (result)
 		goto error_after_create_exported_object;
@@ -1768,8 +1764,6 @@ static int _cache_mngt_create_core_exp_obj(ocf_core_t core, void *cntx)
 	if (result)
 		return result;
 
-	result = kcas_core_activate_exported_object(core);
-
 	return result;
 }
 
@@ -1830,12 +1824,6 @@ static int cache_mngt_initialize_cache_exported_object(ocf_cache_t cache)
 	if (result)
 		return result;
 
-	result = kcas_cache_activate_exported_object(cache);
-	if (result) {
-		cache_mngt_destroy_cache_exp_obj(cache);
-		return result;
-	}
-
 	cache_priv->cache_exp_obj_initialized = true;
 
 	return 0;
diff --git a/modules/cas_cache/volume/vol_block_dev_top.c b/modules/cas_cache/volume/vol_block_dev_top.c
index eb92efa..bdefa3e 100644
--- a/modules/cas_cache/volume/vol_block_dev_top.c
+++ b/modules/cas_cache/volume/vol_block_dev_top.c
@@ -601,19 +601,6 @@ err:
 /**
  * @brief this routine actually adds /dev/casM-N inode
  */
-static int kcas_volume_activate_exported_object(ocf_volume_t volume,
-		struct cas_exp_obj_ops *ops)
-{
-	struct bd_object *bvol = bd_object(volume);
-	int result;
-
-	result = cas_exp_obj_activate(bvol->dsk);
-	if (result == -EEXIST)
-		result = -KCAS_ERR_FILE_EXISTS;
-
-	return result;
-}
-
 int kcas_core_create_exported_object(ocf_core_t core)
 {
 	ocf_cache_t cache = ocf_core_get_cache(core);
@@ -638,23 +625,6 @@ int kcas_core_destroy_exported_object(ocf_core_t core)
 	return kcas_volume_destroy_exported_object(volume);
 }
 
-int kcas_core_activate_exported_object(ocf_core_t core)
-{
-	ocf_cache_t cache = ocf_core_get_cache(core);
-	ocf_volume_t volume = ocf_core_get_volume(core);
-	int result;
-
-	result = kcas_volume_activate_exported_object(volume,
-			&kcas_core_exp_obj_ops);
-	if (result) {
-		printk(KERN_ERR "Cannot activate exported object, %s.%s. "
-				"Error code %d\n", ocf_cache_get_name(cache),
-				ocf_core_get_name(core), result);
-	}
-
-	return result;
-}
-
 int kcas_cache_create_exported_object(ocf_cache_t cache)
 {
 	ocf_volume_t volume = ocf_cache_get_volume(cache);
@@ -677,22 +647,6 @@ int kcas_cache_destroy_exported_object(ocf_cache_t cache)
 	return kcas_volume_destroy_exported_object(volume);
 }
 
-int kcas_cache_activate_exported_object(ocf_cache_t cache)
-{
-	ocf_volume_t volume = ocf_cache_get_volume(cache);
-	int result;
-
-	result = kcas_volume_activate_exported_object(volume,
-			&kcas_cache_exp_obj_ops);
-	if (result) {
-		printk(KERN_ERR "Cannot activate cache %s exported object. "
-				"Error code %d\n", ocf_cache_get_name(cache),
-				result);
-	}
-
-	return result;
-}
-
 static int kcas_core_lock_exported_object(ocf_core_t core, void *cntx)
 {
 	int result;
diff --git a/modules/cas_cache/volume/vol_block_dev_top.h b/modules/cas_cache/volume/vol_block_dev_top.h
index 0c3320f..1ebc5a5 100644
--- a/modules/cas_cache/volume/vol_block_dev_top.h
+++ b/modules/cas_cache/volume/vol_block_dev_top.h
@@ -1,5 +1,5 @@
 /*
-* Copyright(c) 2012-2021 Intel Corporation
+* Copyright(c) 2012-2022 Intel Corporation
 * SPDX-License-Identifier: BSD-3-Clause
 */
 
@@ -9,12 +9,10 @@
 
 int kcas_core_create_exported_object(ocf_core_t core);
 int kcas_core_destroy_exported_object(ocf_core_t core);
-int kcas_core_activate_exported_object(ocf_core_t core);
 
 int kcas_cache_destroy_all_core_exported_objects(ocf_cache_t cache);
 
 int kcas_cache_create_exported_object(ocf_cache_t cache);
 int kcas_cache_destroy_exported_object(ocf_cache_t cache);
-int kcas_cache_activate_exported_object(ocf_cache_t cache);
 
 #endif /* __VOL_BLOCK_DEV_TOP_H__ */