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, 74 insertions, 0 deletions

diff --git a/net/rxrpc/skbuff.c b/net/rxrpc/skbuff.c
new file mode 100644
index 000000000..e2169d1a1
--- /dev/null
+++ b/net/rxrpc/skbuff.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Socket buffer accounting
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/af_rxrpc.h>
+#include "ar-internal.h"
+
+#define select_skb_count(skb) (&rxrpc_n_rx_skbs)
+
+/*
+ * Note the allocation or reception of a socket buffer.
+ */
+void rxrpc_new_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
+{
+	int n = atomic_inc_return(select_skb_count(skb));
+	trace_rxrpc_skb(skb, refcount_read(&skb->users), n, why);
+}
+
+/*
+ * Note the re-emergence of a socket buffer from a queue or buffer.
+ */
+void rxrpc_see_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
+{
+	if (skb) {
+		int n = atomic_read(select_skb_count(skb));
+		trace_rxrpc_skb(skb, refcount_read(&skb->users), n, why);
+	}
+}
+
+/*
+ * Note the addition of a ref on a socket buffer.
+ */
+void rxrpc_get_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
+{
+	int n = atomic_inc_return(select_skb_count(skb));
+	trace_rxrpc_skb(skb, refcount_read(&skb->users), n, why);
+	skb_get(skb);
+}
+
+/*
+ * Note the destruction of a socket buffer.
+ */
+void rxrpc_free_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
+{
+	if (skb) {
+		int n = atomic_dec_return(select_skb_count(skb));
+		trace_rxrpc_skb(skb, refcount_read(&skb->users), n, why);
+		consume_skb(skb);
+	}
+}
+
+/*
+ * Clear a queue of socket buffers.
+ */
+void rxrpc_purge_queue(struct sk_buff_head *list)
+{
+	struct sk_buff *skb;
+
+	while ((skb = skb_dequeue((list))) != NULL) {
+		int n = atomic_dec_return(select_skb_count(skb));
+		trace_rxrpc_skb(skb, refcount_read(&skb->users), n,
+				rxrpc_skb_put_purge);
+		consume_skb(skb);
+	}
+}