hv_pci_enter_d0(9)

💅 hv_pci_enter_d0 — a Kernel API Manual moment

okay so bestie, we're in the Kernel API Manual today and the star of the show is hv_pci_enter_d0(9) ✨ she's a tiny function with a big job and honestly? we stan.

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🎀 NAME 🎀

hv_pci_enter_d0 — brings the "bus" into the D0 power state 🔥 (yes the quotes around "bus" are doing a lot of work here, and yes we're keeping them fr fr)

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✨ SYNOPSIS ✨

int hv_pci_enter_d0 (struct hv_device *hdev );

like literally that's it, that's the whole call 💅

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🦋 ARGUMENTS 🦋

• hdev — VMBus's tracking struct for this root PCI bus 🫶 that's your whole input, bestie, one single pointer to the tracking struct VMBus keeps for the root PCI bus. she doesn't need anything else, she's low maintenance.

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👑 RETURN 👑

• 0 on success 🎉 slay
• -errno on failure 😭 so like, whatever negative errno value it hands back, that's your answer. check it, always check it.

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🌸 SEE ALSO 🌸

the girlies in the group chat, aka the Kernel file ./drivers/pci/controller/pci-hyperv.c and this entire extended friend group:

• struct hv_msi_desc(9)
• struct hv_msi_desc2(9)
• struct tran_int_desc(9)
• hv_irq_retarget_interrupt(9)
• hv_pci_generic_compl(9)
• devfn_to_wslot(9)
• wslot_to_devfn(9)
• _hv_pcifront_read_config(9)
• _hv_pcifront_write_config(9)
• hv_pcifront_read_config(9)
• hv_pcifront_write_config(9)
• hv_pci_read_config_compl(9)
• hv_read_config_block(9)
• hv_pci_write_config_compl(9)
• hv_write_config_block(9)
• hv_register_block_invalidate(9)
• hv_msi_free(9)
• hv_compose_msi_msg(9)
• hv_pcie_init_irq_domain(9)
• get_bar_size(9)
• survey_child_resources(9)
• prepopulate_bars(9)
• create_root_hv_pci_bus(9)
• q_resource_requirements(9)
• new_pcichild_device(9)
• get_pcichild_wslot(9)
• pci_devices_present_work(9)
• hv_pci_start_relations_work(9)
• hv_pci_devices_present(9)
• hv_pci_devices_present2(9)
• hv_eject_device_work(9)
• hv_pci_eject_device(9)
• hv_pci_onchannelcallback(9)
• hv_pci_protocol_negotiation(9)
• hv_pci_free_bridge_windows(9)
• hv_pci_allocate_bridge_windows(9)
• hv_allocate_config_window(9)
• hv_pci_query_relations(9)
• hv_send_resources_allocated(9)
• hv_send_resources_released(9)
• hv_pci_probe(9)
• hv_pci_remove(9)

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ngl that's a whole lot of friends but they're all listed, every single one, no cap 💖

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mwah that's the page! brought to you from the ./drivers/pci/controller directory, dated October 2026, and this whole thing is page hv_pci_enter_d0(9) of the Kernel API Manual — ily, go read pci-hyperv.c bestie 🧚💜