msix_capability_init(9)

💖 msix_capability_init(9) 💖

okay bestie, so this is a page from the Kernel API Manual and it's literally all about msix_capability_init — the glow-up function that configures a device's MSI-X capability. slay.

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✨ NAME ✨

msix_capability_init — configure device's MSI-X capability. no cap, that's the whole vibe.

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🌸 SYNOPSIS 🌸

int msix_capability_init (struct pci_dev *dev , struct msix_entry
*entries , int nvec , struct irq_affinity *affd );

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🎀 ARGUMENTS 🎀

• dev — pointer to the pci_dev data structure of MSI-X device function. it's giving "main character" — this is the device we're setting up, bestie 🫶
• entries — pointer to an array of struct msix_entry entries. like a little lineup of entries, iconic 💅
• nvec — number of entries. just a count, ngl, not that deep 🦋
• affd — Optional pointer to enable automatic affinity assignment. optional! it's there if you want it, no pressure ✨

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🦋 DESCRIPTION 🦋

okay so the way that this works is: it sets up the MSI-X capability structure of a device function with a single MSI-X IRQ. literally one. periodt 💅

A return of zero indicates the successful setup of requested MSI-X entries with allocated IRQs, or non-zero for otherwise. so like, zero = slay 🎉, anything else = not slay 😭. the vibe check is the return value, iykyk.

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💜 SEE ALSO 💜

these are the besties in the same friend group, go check them out:

• Kernel file ./drivers/pci/msi/msi.c
• pci_msi_supported(9)
• pci_msi_mask_irq(9)
• pci_msi_unmask_irq(9)
• msi_capability_init(9)
• pci_msi_vec_count(9)
• msix_prepare_msi_desc(9)
• pci_msix_write_tph_tag(9)

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💖 source file lives in ./drivers/pci/msi, dated October 2026, and yes this whole page is literally msix_capability_init(9). mwah, bye bestie! 🧚🌟

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