PCI: Add pci_irq_type() to query the allocated interrupt typegrafted

Add a helper that returns PCI_IRQ_MSIX, PCI_IRQ_MSI, or PCI_IRQ_INTX
based on the interrupt type the PCI core selected after
pci_alloc_irq_vectors().

Several drivers already open-code this check against pdev->msix_enabled
and pdev->msi_enabled, or even open code this helper [1].

A common helper avoids the duplication and keeps drivers from accessing
the bitfield directly (see also [2]).

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Link: https://elixir.bootlin.com/linux/v7.1/source/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c#L196 [1]
Inspired-by: John Hubbard <jhubbard@nvidia.com>
Link: https://lore.kernel.org/all/DKKG2QM3YJYB.Z2H2B2UXJ75N@kernel.org/ [2]
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260813165234.620555-5-dakr@kernel.org
[ Add missing pci_irq_type() stub for CONFIG_PCI=n. ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>

1 files changed, 99 insertions, 0 deletions

diff --git a/security/landlock/errata.h b/security/landlock/errata.h
new file mode 100644
index 000000000..8e626acca
--- /dev/null
+++ b/security/landlock/errata.h
@@ -0,0 +1,99 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Landlock - Errata information
+ *
+ * Copyright © 2025 Microsoft Corporation
+ */
+
+#ifndef _SECURITY_LANDLOCK_ERRATA_H
+#define _SECURITY_LANDLOCK_ERRATA_H
+
+#include <linux/init.h>
+
+struct landlock_erratum {
+	const int abi;
+	const u8 number;
+};
+
+/* clang-format off */
+#define LANDLOCK_ERRATUM(NUMBER) \
+	{ \
+		.abi = LANDLOCK_ERRATA_ABI, \
+		.number = NUMBER, \
+	},
+/* clang-format on */
+
+/*
+ * Some fixes may require user space to check if they are applied on the running
+ * kernel before using a specific feature.  For instance, this applies when a
+ * restriction was previously too restrictive and is now getting relaxed (for
+ * compatibility or semantic reasons).  However, non-visible changes for
+ * legitimate use (e.g. security fixes) do not require an erratum.
+ */
+static const struct landlock_erratum landlock_errata_init[] __initconst = {
+
+/*
+ * Only Sparse may not implement __has_include.  If a compiler does not
+ * implement __has_include, a warning will be printed at boot time (see
+ * setup.c).
+ */
+#ifdef __has_include
+
+#define LANDLOCK_ERRATA_ABI 1
+#if __has_include("errata/abi-1.h")
+#include "errata/abi-1.h"
+#endif
+#undef LANDLOCK_ERRATA_ABI
+
+#define LANDLOCK_ERRATA_ABI 2
+#if __has_include("errata/abi-2.h")
+#include "errata/abi-2.h"
+#endif
+#undef LANDLOCK_ERRATA_ABI
+
+#define LANDLOCK_ERRATA_ABI 3
+#if __has_include("errata/abi-3.h")
+#include "errata/abi-3.h"
+#endif
+#undef LANDLOCK_ERRATA_ABI
+
+#define LANDLOCK_ERRATA_ABI 4
+#if __has_include("errata/abi-4.h")
+#include "errata/abi-4.h"
+#endif
+#undef LANDLOCK_ERRATA_ABI
+
+#define LANDLOCK_ERRATA_ABI 5
+#if __has_include("errata/abi-5.h")
+#include "errata/abi-5.h"
+#endif
+#undef LANDLOCK_ERRATA_ABI
+
+#define LANDLOCK_ERRATA_ABI 6
+#if __has_include("errata/abi-6.h")
+#include "errata/abi-6.h"
+#endif
+#undef LANDLOCK_ERRATA_ABI
+
+/*
+ * For each new erratum, we need to include all the ABI files up to the impacted
+ * ABI to make all potential future intermediate errata easy to backport.
+ *
+ * If such change involves more than one ABI addition, then it must be in a
+ * dedicated commit with the same Fixes tag as used for the actual fix.
+ *
+ * Each commit creating a new security/landlock/errata/abi-*.h file must have a
+ * Depends-on tag to reference the commit that previously added the line to
+ * include this new file, except if the original Fixes tag is enough.
+ *
+ * Each erratum must be documented in its related ABI file, and a dedicated
+ * commit must update Documentation/userspace-api/landlock.rst to include this
+ * erratum.  This commit will not be backported.
+ */
+
+#endif
+
+	{}
+};
+
+#endif /* _SECURITY_LANDLOCK_ERRATA_H */