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, 50 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-block-loop b/Documentation/ABI/testing/sysfs-block-loop
new file mode 100644
index 000000000..627f4eb87
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-block-loop
@@ -0,0 +1,50 @@
+What:		/sys/block/loopX/loop/autoclear
+Date:		Aug, 2010
+KernelVersion:	v2.6.37
+Contact:	linux-block@vger.kernel.org
+Description:
+		(RO) Shows if the device is in autoclear mode or not ( "1" or
+		"0"). Autoclear (if set) indicates that the loopback device will
+		self-distruct after last close.
+
+What:		/sys/block/loopX/loop/backing_file
+Date:		Aug, 2010
+KernelVersion:	v2.6.37
+Contact:	linux-block@vger.kernel.org
+Description:
+		(RO) The path of the backing file that the loop device maps its
+		data blocks to.
+
+What:		/sys/block/loopX/loop/offset
+Date:		Aug, 2010
+KernelVersion:	v2.6.37
+Contact:	linux-block@vger.kernel.org
+Description:
+		(RO) Start offset (in bytes).
+
+What:		/sys/block/loopX/loop/sizelimit
+Date:		Aug, 2010
+KernelVersion:	v2.6.37
+Contact:	linux-block@vger.kernel.org
+Description:
+		(RO) The size (in bytes) that the block device maps, starting
+		from the offset.
+
+What:		/sys/block/loopX/loop/partscan
+Date:		Aug, 2011
+KernelVersion:	v3.10
+Contact:	linux-block@vger.kernel.org
+Description:
+		(RO) Shows if automatic partition scanning is enabled for the
+		device or not ("1" or "0"). This can be requested individually
+		per loop device during its setup by setting LO_FLAGS_PARTSCAN in
+		in the ioctl request. By default, no partition tables are
+		scanned.
+
+What:		/sys/block/loopX/loop/dio
+Date:		Aug, 2015
+KernelVersion:	v4.10
+Contact:	linux-block@vger.kernel.org
+Description:
+		(RO) Shows if direct IO is being used to access backing file or
+		not ("1 or "0").