vfio_ap_mdev_validate_masks(9)

💅 vfio_ap_mdev_validate_masks — the kernel API manual, bestie edition ✨

okay so real talk, this page lives in the Kernel API Manual, and today's main character is vfio_ap_mdev_validate_masks. yes it's a long name. yes it ate. let's get into it 🫶

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✨ NAME ✨

vfio_ap_mdev_validate_masks — this one's whole job is checking that the APQNs assigned to the mdev are not reserved for the default zcrypt driver, and not already assigned to another mdev. that's it. that's the vibe check 💅

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🌸 SYNOPSIS 🌸

int vfio_ap_mdev_validate_masks (struct ap_matrix_mdev *matrix_mdev );

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🦋 ARGUMENTS 🦋

• matrix_mdev — the mdev that the APQNs being validated are assigned to. like, this is the one we're checking up on 👑

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⭐ RETURN ⭐

bestie it returns one of the following values, no cap:

• the error returned from the ap_apqn_in_matrix_owned_by_def_drv function — most likely -EBUSY, which means the ap_attr_mutex lock is already held 🔒
• EADDRNOTAVAIL if an APQN assigned to matrix_mdev is reserved for the zcrypt default driver 🙈
• EADDRINUSE if an APQN assigned to matrix_mdev is assigned to another mdev 💀
• a zero, indicating validation succeeded ✅ slay

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🎀 SEE ALSO 🎀

the kernel file, obviously:

• Kernel file ./drivers/s390/crypto/vfio_ap_ops.c

and the whole friend group (iykyk):

• get_update_locks_for_kvm(9), release_update_locks_for_kvm(9)
• get_update_locks_for_mdev(9), release_update_locks_for_mdev(9)
• get_update_locks_by_apqn(9), get_update_locks_for_queue(9)
• vfio_ap_mdev_get_queue(9), vfio_ap_wait_for_irqclear(9)
• vfio_ap_free_aqic_resources(9), vfio_ap_irq_disable(9)
• vfio_ap_validate_nib(9), ensure_nib_shared(9), vfio_ap_irq_enable(9)
• vfio_ap_le_guid_to_be_uuid(9), handle_pqap(9)
• vfio_ap_mdev_verify_no_sharing(9)
• assign_adapter_store(9), vfio_ap_mdev_unlink_adapter(9), unassign_adapter_store(9)
• assign_domain_store(9), unassign_domain_store(9)
• assign_control_domain_store(9), unassign_control_domain_store(9)
• vfio_ap_mdev_set_kvm(9), vfio_ap_mdev_unset_kvm(9)
• vfio_ap_mdev_resource_in_use(9)
• vfio_ap_mdev_hot_unplug_cfg(9), vfio_ap_mdev_cfg_remove(9), vfio_ap_mdev_on_cfg_remove(9)
• vfio_ap_filter_apid_by_qtype(9)
• vfio_ap_mdev_cfg_add(9), vfio_ap_mdev_on_cfg_add(9), vfio_ap_on_cfg_changed(9)

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ngl, that see-also list is giving "group chat at 2am" energy — everybody's there, everybody's tagged 💜

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and that's the page!! sourced from ./drivers/s390/crypto, dated October 2026, filed under vfio_ap_mdev_validate_masks(9) — mwah, go validate those masks bestie 💖🌈