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, 111 insertions, 0 deletions

diff --git a/block/partitions/of.c b/block/partitions/of.c
new file mode 100644
index 000000000..53664ea06
--- /dev/null
+++ b/block/partitions/of.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/blkdev.h>
+#include <linux/major.h>
+#include <linux/of.h>
+#include <linux/string.h>
+#include "check.h"
+
+static int validate_of_partition(struct device_node *np, int slot)
+{
+	u64 offset, size;
+	int len;
+
+	const __be32 *reg = of_get_property(np, "reg", &len);
+	int a_cells = of_n_addr_cells(np);
+	int s_cells = of_n_size_cells(np);
+
+	/* Make sure reg len match the expected addr and size cells */
+	if (len / sizeof(*reg) != a_cells + s_cells)
+		return -EINVAL;
+
+	/* Validate offset conversion from bytes to sectors */
+	offset = of_read_number(reg, a_cells);
+	if (offset % SECTOR_SIZE)
+		return -EINVAL;
+
+	/* Validate size conversion from bytes to sectors */
+	size = of_read_number(reg + a_cells, s_cells);
+	if (!size || size % SECTOR_SIZE)
+		return -EINVAL;
+
+	return 0;
+}
+
+static void add_of_partition(struct parsed_partitions *state, int slot,
+			     struct device_node *np)
+{
+	struct partition_meta_info *info;
+	const char *partname;
+	int len;
+
+	const __be32 *reg = of_get_property(np, "reg", &len);
+	int a_cells = of_n_addr_cells(np);
+	int s_cells = of_n_size_cells(np);
+
+	/* Convert bytes to sector size */
+	u64 offset = of_read_number(reg, a_cells) / SECTOR_SIZE;
+	u64 size = of_read_number(reg + a_cells, s_cells) / SECTOR_SIZE;
+
+	put_partition(state, slot, offset, size);
+
+	if (of_property_read_bool(np, "read-only"))
+		state->parts[slot].flags |= ADDPART_FLAG_READONLY;
+
+	/*
+	 * Follow MTD label logic, search for label property,
+	 * fallback to node name if not found.
+	 */
+	info = &state->parts[slot].info;
+	partname = of_get_property(np, "label", &len);
+	if (!partname)
+		partname = of_get_property(np, "name", &len);
+	strscpy(info->volname, partname, sizeof(info->volname));
+
+	seq_buf_printf(&state->pp_buf, "(%s)", info->volname);
+}
+
+int of_partition(struct parsed_partitions *state)
+{
+	struct device *ddev = disk_to_dev(state->disk);
+	struct device_node *np;
+	int slot;
+
+	struct device_node *partitions_np = of_node_get(ddev->of_node);
+
+	if (!partitions_np ||
+	    !of_device_is_compatible(partitions_np, "fixed-partitions")) {
+		of_node_put(partitions_np);
+		return 0;
+	}
+
+	slot = 1;
+	/* Validate parition offset and size */
+	for_each_child_of_node(partitions_np, np) {
+		if (validate_of_partition(np, slot)) {
+			of_node_put(np);
+			of_node_put(partitions_np);
+
+			return -1;
+		}
+
+		slot++;
+	}
+
+	slot = 1;
+	for_each_child_of_node(partitions_np, np) {
+		if (slot >= state->limit) {
+			of_node_put(np);
+			break;
+		}
+
+		add_of_partition(state, slot, np);
+
+		slot++;
+	}
+
+	seq_buf_puts(&state->pp_buf, "\n");
+
+	of_node_put(partitions_np);
+	return 1;
+}