ntb_db_event(9)

🎀 ntb_db_event(9) 🎀

okay bestie, this page is from the Kernel API Manual, and it's literally about telling a driver context that a doorbell event happened 🔔. tiny function, big “I was called” energy.

🌸 NAME 🌸

ntb_db_event — notify driver context of a doorbell event ✨

✨ SYNOPSIS ✨

void ntb_db_event (struct ntb_dev *ntb , int vector );

🫶 ARGUMENTS 🫶

• ntb — NTB device context. that's the device context we're working with 💅
• vector — Interrupt vector number. bestie, this is the number that says which vector got the interrupt.

💖 DESCRIPTION 💖

so the whole point of ntb_db_event is: notify the driver context of a doorbell event. 🔔 that's the function. that's the vibe.

If hardware supports multiple interrupt vectors for doorbells, the vector number indicates which vector received the interrupt. The vector number is relative to the first vector used for doorbells, starting at zero, and must be less than ntb_db_vector_count. no cap, that boundary matters.

The driver may call ntb_db_read to check which doorbell bits need service, and ntb_db_vector_mask to determine which of those bits are associated with the vector number. slay, now you know which bits are the main character. 👑

👑 SEE ALSO 👑

Kernel file ./include/linux/ntb.h — and then the whole NTB cinematic universe:

• enum ntb_topo(9)
• enum ntb_speed(9)
• enum ntb_width(9)
• enum ntb_default_port(9)
• struct ntb_client_ops(9)
• struct ntb_ctx_ops(9)
• struct ntb_dev_ops(9)
• struct ntb_client(9)
• struct ntb_dev(9)
• ntb_register_client(9)
• ntb_unregister_client(9)
• ntb_register_device(9)
• ntb_unregister_device(9)
• ntb_set_ctx(9)
• ntb_clear_ctx(9)
• ntb_link_event(9)
• ntb_msg_event(9)
• ntb_default_port_number(9)
• ntb_default_peer_port_count(9)
• ntb_default_peer_port_number(9)
• ntb_default_peer_port_idx(9)
• ntb_port_number(9)
• ntb_peer_port_count(9)
• ntb_peer_port_number(9)
• ntb_logical_port_number(9)
• ntb_peer_logical_port_number(9)
• ntb_peer_port_idx(9)
• ntb_link_is_up(9)
• ntb_link_enable(9)
• ntb_link_disable(9)
• ntb_mw_count(9)
• ntb_mw_get_align(9)
• ntb_mw_set_trans(9)
• ntb_mw_clear_trans(9)
• ntb_peer_mw_count(9)
• ntb_peer_mw_get_addr(9)
• ntb_peer_mw_set_trans(9)
• ntb_peer_mw_clear_trans(9)
• ntb_db_is_unsafe(9)
• ntb_db_valid_mask(9)
• ntb_db_vector_count(9)
• ntb_db_vector_mask(9)
• ntb_db_read(9)
• ntb_db_set(9)
• ntb_db_clear(9)
• ntb_db_read_mask(9)
• ntb_db_set_mask(9)
• ntb_db_clear_mask(9)
• ntb_peer_db_addr(9)
• ntb_peer_db_read(9)
• ntb_peer_db_set(9)
• ntb_peer_db_clear(9)
• ntb_peer_db_read_mask(9)
• ntb_peer_db_set_mask(9)
• ntb_peer_db_clear_mask(9)
• ntb_spad_is_unsafe(9)
• ntb_spad_count(9)
• ntb_spad_read(9)
• ntb_spad_write(9)
• ntb_peer_spad_addr(9)
• ntb_peer_spad_read(9)
• ntb_peer_spad_write(9)
• ntb_msg_count(9)
• ntb_msg_inbits(9)
• ntb_msg_outbits(9)
• ntb_msg_read_sts(9)
• ntb_msg_clear_sts(9)
• ntb_msg_set_mask(9)
• ntb_msg_clear_mask(9)
• ntb_msg_read(9)
• ntb_peer_msg_write(9)
• ntb_get_dma_dev(9)
• ntb_peer_resource_idx(9)
• ntb_peer_highest_mw_idx(9)

k that's the whole page bestie 🫶 source/version: ./include/linux, date: October 2026. go off, and remember: doorbells are not a personality trait, but ntb_db_event(9) kinda is 💜