[RFC PATCH v4 10/38] NTB: core: Add .get_private_data() to ntb_dev_ops

Koichiro Den
2026-01-18T13:55:16Z

Add an optional get_private_data() callback to retrieve a private data
specific to the underlying hardware driver, e.g. pci_epc device
associated with the NTB implementation.

Signed-off-by: Koichiro Den <den@valinux.co.jp>
---
include/linux/ntb.h | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

diff --git a/include/linux/ntb.h b/include/linux/ntb.h
index 84908753f446..aa888219732a 100644
--- a/include/linux/ntb.h
+++ b/include/linux/ntb.h
@@ -262,6 +262,7 @@ struct ntb_mw_subrange {
* @msg_clear_mask: See ntb_msg_clear_mask().
* @msg_read: See ntb_msg_read().
* @peer_msg_write: See ntb_peer_msg_write().
+ * @get_private_data: See ntb_get_private_data().
*/
struct ntb_dev_ops {
int (*port_number)(struct ntb_dev *ntb);
@@ -338,6 +339,7 @@ struct ntb_dev_ops {
int (*msg_clear_mask)(struct ntb_dev *ntb, u64 mask_bits);
u32 (*msg_read)(struct ntb_dev *ntb, int *pidx, int midx);
int (*peer_msg_write)(struct ntb_dev *ntb, int pidx, int midx, u32 msg);
+ void *(*get_private_data)(struct ntb_dev *ntb);
};

static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops)
@@ -401,6 +403,9 @@ static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops)
/* !ops->msg_clear_mask == !ops->msg_count && */
!ops->msg_read == !ops->msg_count &&
!ops->peer_msg_write == !ops->msg_count &&
+
+ /* Miscellaneous optional callbacks */
+ /* ops->get_private_data && */
1;
}

@@ -1609,6 +1614,21 @@ static inline int ntb_peer_msg_write(struct ntb_dev *ntb, int pidx, int midx,
return ntb->ops->peer_msg_write(ntb, pidx, midx, msg);
}

+/**
+ * ntb_get_private_data() - get private data specific to the hardware driver
+ * @ntb: NTB device context.
+ *
+ * Retrieve private data specific to the hardware driver.
+ *
+ * Return: Pointer to the private data if available, or %NULL otherwise.
+ */
+static inline void *ntb_get_private_data(struct ntb_dev *ntb)
+{
+ if (!ntb->ops->get_private_data)
+ return NULL;
+ return ntb->ops->get_private_data(ntb);
+}
+
/**
* ntb_peer_resource_idx() - get a resource index for a given peer idx
* @ntb: NTB device context.
--
2.51.0