On Sun, Nov 30, 2025 at 01:03:48AM +0900, Koichiro Den wrote:
> Add an optional get_pci_epc() callback to retrieve the underlying
> pci_epc device associated with the NTB implementation.
EPC run at EP side, this is running at RC side. Why need get EP side's
controller pointer?
Frank
>
> Signed-off-by: Koichiro Den <den@valinux.co.jp>
> ---
> drivers/ntb/hw/epf/ntb_hw_epf.c | 11 +----------
> include/linux/ntb.h | 21 +++++++++++++++++++++
> 2 files changed, 22 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/ntb/hw/epf/ntb_hw_epf.c b/drivers/ntb/hw/epf/ntb_hw_epf.c
> index a3ec411bfe49..d55ce6b0fad4 100644
> --- a/drivers/ntb/hw/epf/ntb_hw_epf.c
> +++ b/drivers/ntb/hw/epf/ntb_hw_epf.c
> @@ -9,6 +9,7 @@
> #include <linux/delay.h>
> #include <linux/module.h>
> #include <linux/pci.h>
> +#include <linux/pci-epf.h>
> #include <linux/slab.h>
> #include <linux/ntb.h>
>
> @@ -49,16 +50,6 @@
>
> #define NTB_EPF_COMMAND_TIMEOUT 1000 /* 1 Sec */
>
> -enum pci_barno {
> - NO_BAR = -1,
> - BAR_0,
> - BAR_1,
> - BAR_2,
> - BAR_3,
> - BAR_4,
> - BAR_5,
> -};
> -
> enum epf_ntb_bar {
> BAR_CONFIG,
> BAR_PEER_SPAD,
> diff --git a/include/linux/ntb.h b/include/linux/ntb.h
> index d7ce5d2e60d0..04dc9a4d6b85 100644
> --- a/include/linux/ntb.h
> +++ b/include/linux/ntb.h
> @@ -64,6 +64,7 @@ struct ntb_client;
> struct ntb_dev;
> struct ntb_msi;
> struct pci_dev;
> +struct pci_epc;
>
> /**
> * enum ntb_topo - NTB connection topology
> @@ -256,6 +257,7 @@ static inline int ntb_ctx_ops_is_valid(const struct ntb_ctx_ops *ops)
> * @msg_clear_mask: See ntb_msg_clear_mask().
> * @msg_read: See ntb_msg_read().
> * @peer_msg_write: See ntb_peer_msg_write().
> + * @get_pci_epc: See ntb_get_pci_epc().
> */
> struct ntb_dev_ops {
> int (*port_number)(struct ntb_dev *ntb);
> @@ -331,6 +333,7 @@ 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);
> + struct pci_epc *(*get_pci_epc)(struct ntb_dev *ntb);
> };
>
> static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops)
> @@ -393,6 +396,9 @@ 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_pci_epc && */
> 1;
> }
>
> @@ -1567,6 +1573,21 @@ 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_pci_epc() - get backing PCI endpoint controller if possible.
> + * @ntb: NTB device context.
> + *
> + * Get the backing PCI endpoint controller representation.
> + *
> + * Return: A pointer to the pci_epc instance if available. or %NULL if not.
> + */
> +static inline struct pci_epc __maybe_unused *ntb_get_pci_epc(struct ntb_dev *ntb)
> +{
> + if (!ntb->ops->get_pci_epc)
> + return NULL;
> + return ntb->ops->get_pci_epc(ntb);
> +}
> +
> /**
> * ntb_peer_resource_idx() - get a resource index for a given peer idx
> * @ntb: NTB device context.
> --
> 2.48.1
>