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, 25 insertions, 0 deletions

diff --git a/scripts/check-function-names.sh b/scripts/check-function-names.sh
new file mode 100755
index 000000000..08071133e
--- /dev/null
+++ b/scripts/check-function-names.sh
@@ -0,0 +1,25 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Certain function names are disallowed due to section name ambiguities
+# introduced by -ffunction-sections.
+#
+# See the comment above TEXT_MAIN in include/asm-generic/vmlinux.lds.h.
+
+objfile="$1"
+
+if [ ! -f "$objfile" ]; then
+	echo "usage: $0 <file.o>" >&2
+	exit 1
+fi
+
+bad_symbols=$(${NM:-nm} "$objfile" | awk '$2 ~ /^[TtWw]$/ {print $3}' | grep -E '^(startup|exit|split|unlikely|hot|unknown)(\.|$)')
+
+if [ -n "$bad_symbols" ]; then
+	echo "$bad_symbols" | while read -r sym; do
+		echo "$objfile: error: $sym() function name creates ambiguity with -ffunction-sections" >&2
+	done
+	exit 1
+fi
+
+exit 0