[RFC PATCH 05/12] nvme: wire-up register/unregister queue f_op callback

[Kanchan Joshi]

From: Anuj Gupta <anuj20.g at samsung.com>

Implement register/unregister handlers for char-device file.

Signed-off-by: Anuj Gupta <anuj20.g at samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k at samsung.com>
---
 drivers/nvme/host/core.c      | 26 +++++++++++++++++++
 drivers/nvme/host/ioctl.c     | 48 +++++++++++++++++++++++++++++++++++
 drivers/nvme/host/multipath.c |  2 ++
 drivers/nvme/host/nvme.h      |  2 ++
 4 files changed, 78 insertions(+)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index ba476c48d566..4462ce50d076 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -4059,6 +4059,30 @@ static int nvme_ns_chr_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
+int nvme_register_queue(struct file *file)
+{
+	struct nvme_ns *ns = container_of(file_inode(file)->i_cdev,
+			struct nvme_ns, cdev);
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	struct request_queue *q = ns ? ns->queue : ctrl->admin_q;
+
+	if (q->mq_ops && q->mq_ops->register_queue)
+		return q->mq_ops->register_queue(ns);
+	return -EINVAL;
+}
+
+int nvme_unregister_queue(struct file *file, int qid)
+{
+	struct nvme_ns *ns = container_of(file_inode(file)->i_cdev,
+			struct nvme_ns, cdev);
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	struct request_queue *q = ns ? ns->queue : ctrl->admin_q;
+
+	if (q->mq_ops && q->mq_ops->unregister_queue)
+		return q->mq_ops->unregister_queue(ns, qid);
+	return -EINVAL;
+}
+
 static const struct file_operations nvme_ns_chr_fops = {
 	.owner		= THIS_MODULE,
 	.open		= nvme_ns_chr_open,
@@ -4067,6 +4091,8 @@ static const struct file_operations nvme_ns_chr_fops = {
 	.compat_ioctl	= compat_ptr_ioctl,
 	.uring_cmd	= nvme_ns_chr_uring_cmd,
 	.uring_cmd_iopoll = nvme_ns_chr_uring_cmd_iopoll,
+	.register_queue	= nvme_register_queue,
+	.unregister_queue = nvme_unregister_queue,
 };
 
 static int nvme_add_ns_cdev(struct nvme_ns *ns)
diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index d24ea2e05156..292a578686b6 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -871,6 +871,54 @@ long nvme_ns_head_chr_ioctl(struct file *file, unsigned int cmd,
 	return ret;
 }
 
+int nvme_ns_head_register_queue(struct file *file)
+{
+	struct cdev *cdev = file_inode(file)->i_cdev;
+	struct nvme_ns_head *head =
+		container_of(cdev, struct nvme_ns_head, cdev);
+	struct nvme_ns *ns;
+	struct nvme_ctrl *ctrl;
+	struct request_queue *q;
+	int srcu_idx, ret = -EINVAL;
+
+	srcu_idx = srcu_read_lock(&head->srcu);
+	ns = nvme_find_path(head);
+	if (!ns)
+		goto out_unlock;
+
+	ctrl = ns->ctrl;
+	q = ns ? ns->queue : ctrl->admin_q;
+	if (q->mq_ops && q->mq_ops->register_queue)
+		ret = q->mq_ops->register_queue(ns);
+out_unlock:
+	srcu_read_unlock(&head->srcu, srcu_idx);
+	return ret;
+}
+
+int nvme_ns_head_unregister_queue(struct file *file, int qid)
+{
+	struct cdev *cdev = file_inode(file)->i_cdev;
+	struct nvme_ns_head *head =
+		container_of(cdev, struct nvme_ns_head, cdev);
+	struct nvme_ns *ns;
+	struct nvme_ctrl *ctrl;
+	struct request_queue *q;
+	int srcu_idx, ret = -EINVAL;
+
+	srcu_idx = srcu_read_lock(&head->srcu);
+	ns = nvme_find_path(head);
+	if (!ns)
+		goto out_unlock;
+
+	ctrl = ns->ctrl;
+	q = ns ? ns->queue : ctrl->admin_q;
+	if (q->mq_ops && q->mq_ops->unregister_queue)
+		ret = q->mq_ops->unregister_queue(ns, qid);
+out_unlock:
+	srcu_read_unlock(&head->srcu, srcu_idx);
+	return ret;
+}
+
 int nvme_ns_head_chr_uring_cmd(struct io_uring_cmd *ioucmd,
 		unsigned int issue_flags)
 {
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 9171452e2f6d..eed30daf1a37 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -471,6 +471,8 @@ static const struct file_operations nvme_ns_head_chr_fops = {
 	.compat_ioctl	= compat_ptr_ioctl,
 	.uring_cmd	= nvme_ns_head_chr_uring_cmd,
 	.uring_cmd_iopoll = nvme_ns_head_chr_uring_cmd_iopoll,
+	.register_queue	= nvme_ns_head_register_queue,
+	.unregister_queue = nvme_ns_head_unregister_queue,
 };
 
 static int nvme_add_ns_head_cdev(struct nvme_ns_head *head)
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 73992dc9dec7..4619a7498f8e 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -843,6 +843,8 @@ int nvme_ns_head_ioctl(struct block_device *bdev, fmode_t mode,
 		unsigned int cmd, unsigned long arg);
 long nvme_ns_head_chr_ioctl(struct file *file, unsigned int cmd,
 		unsigned long arg);
+int nvme_ns_head_register_queue(struct file *file);
+int nvme_ns_head_unregister_queue(struct file *file, int qid);
 long nvme_dev_ioctl(struct file *file, unsigned int cmd,
 		unsigned long arg);
 int nvme_ns_chr_uring_cmd_iopoll(struct io_uring_cmd *ioucmd,
-- 
2.25.1