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, 53 insertions, 0 deletions

diff --git a/scripts/include/xalloc.h b/scripts/include/xalloc.h
new file mode 100644
index 000000000..cdadb07d0
--- /dev/null
+++ b/scripts/include/xalloc.h
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef XALLOC_H
+#define XALLOC_H
+
+#include <stdlib.h>
+#include <string.h>
+
+static inline void *xmalloc(size_t size)
+{
+	void *p = malloc(size);
+
+	if (!p)
+		exit(1);
+	return p;
+}
+
+static inline void *xcalloc(size_t nmemb, size_t size)
+{
+	void *p = calloc(nmemb, size);
+
+	if (!p)
+		exit(1);
+	return p;
+}
+
+static inline void *xrealloc(void *p, size_t size)
+{
+	p = realloc(p, size);
+	if (!p)
+		exit(1);
+	return p;
+}
+
+static inline char *xstrdup(const char *s)
+{
+	char *p = strdup(s);
+
+	if (!p)
+		exit(1);
+	return p;
+}
+
+static inline char *xstrndup(const char *s, size_t n)
+{
+	char *p = strndup(s, n);
+
+	if (!p)
+		exit(1);
+	return p;
+}
+
+#endif /* XALLOC_H */