arch/s390/include/asm/msi.h

Source file repositories/reference/linux-study-clean/arch/s390/include/asm/msi.h

File Facts

System: Linux kernel
Corpus path: arch/s390/include/asm/msi.h
Extension: .h
Size: 527 bytes
Lines: 18
Domain: Architecture Layer
Bucket: arch/s390
Inferred role: Architecture Layer: implementation source
Status: source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
Touches IRQ or DMA behavior; this matters for the representative real-device path.

Dependency Surface

asm-generic/msi.h

Detected Declarations

No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

#ifndef _ASM_S390_MSI_H
#define _ASM_S390_MSI_H
#include <asm-generic/msi.h>

/*
 * Work around S390 not using irq_domain at all so we can't set
 * IRQ_DOMAIN_FLAG_ISOLATED_MSI. See for an explanation how it works:
 *
 * https://lore.kernel.org/r/31af8174-35e9-ebeb-b9ef-74c90d4bfd93@linux.ibm.com/
 *
 * Note this is less isolated than the ARM/x86 versions as userspace can trigger
 * MSI belonging to kernel devices within the same gisa.
 */
#define arch_is_isolated_msi() true

#endif

Annotation

Immediate include surface: `asm-generic/msi.h`.
Atlas domain: Architecture Layer / arch/s390.
Implementation status: source implementation candidate.
IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

Implementation Notes

This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.