iommu_setup_default_domain(9)

💖 NAME 💖

okay so bestie, welcome to the page for iommu_setup_default_domain(9) — yep, that's the manual name, and this is Kernel API Manual territory. 💅 The whole point: set the default_domain for the group. That's the name-and-purpose moment, no cap. ✨

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✨ SYNOPSIS ✨

int iommu_setup_default_domain (struct iommu_group *group , int
target_type );

That's the call, bestie — int return, two arguments, very main-character energy. 🎀

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🎀 ARGUMENTS 🎀

• group — the group to change. Like, the actual group getting its default-domain situation adjusted. 🫶
• target_type — the domain type to set as the default_domain. That's the vibe you're asking for. 🌸

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🦋 DESCRIPTION 🦋

Here's the tea, bestie: this allocates a default domain and sets it as the current domain on the group. Literally the whole glow-up. 💖

If the group already has a default domain, it will be changed to target_type. So yes, it can switch things up. 🔥

When target_type is 0, the default domain is selected based on driver and system preferences. That's the "let the driver and system preferences cook" case. 🧚

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🌈 SEE ALSO 🌈

Kernel file: ./drivers/iommu/iommu.c — that's where this lives, iykyk. 👑

The whole SEE ALSO squad, in order:

• iommu_device_register(9)
• iommu_insert_resv_region(9)
• iommu_group_alloc(9)
• iommu_group_get_iommudata(9)
• iommu_group_set_iommudata(9)
• iommu_group_set_name(9)
• iommu_group_add_device(9)
• iommu_group_remove_device(9)
• iommu_group_mutex_assert(9)
• iommu_group_for_each_dev(9)
• iommu_group_get(9)
• iommu_group_ref_get(9)
• iommu_group_put(9)
• iommu_group_id(9)
• device_iommu_capable(9)
• iommu_group_has_isolated_msi(9)
• iommu_set_fault_handler(9)
• iommu_paging_domain_alloc_flags(9)
• iommu_attach_device(9)
• iommu_get_domain_for_dev(9)
• iommu_driver_get_domain_for_dev(9)
• iommu_attach_group(9)
• iommu_unmap(9)
• iommu_unmap_fast(9)
• report_iommu_fault(9)
• iommu_get_resv_regions(9)
• iommu_put_resv_regions(9)
• iommu_device_use_default_domain(9)
• iommu_device_unuse_default_domain(9)
• iommu_group_claim_dma_owner(9)
• iommu_device_claim_dma_owner(9)
• iommu_group_release_dma_owner(9)
• iommu_device_release_dma_owner(9)
• iommu_group_dma_owner_claimed(9)
• iommu_replace_device_pasid(9)
• iommu_attach_handle_get(9)
• iommu_attach_group_handle(9)
• iommu_detach_group_handle(9)
• iommu_replace_group_handle(9)
• pci_dev_reset_iommu_prepare(9)
• pci_dev_reset_iommu_done(9)
• iommu_dma_prepare_msi(9)

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okay that's the page! cute sign-off time: source/version is ./drivers/iommu, dated October 2026, and it's the iommu_setup_default_domain(9) manual. mwah, go be iconic with those IOMMU groups 💋💖🎀