This is a note to let you know that I've just added the patch titled
vfio/pci: Enable iowrite64 and ioread64 for vfio pci
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
vfio-pci-enable-iowrite64-and-ioread64-for-vfio-pci.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9b5e6f7a01498d2cd11d29d582f278dac756f248
Author: Ramesh Thomas <ramesh.thomas@xxxxxxxxx>
Date: Tue Dec 10 05:19:37 2024 -0800
vfio/pci: Enable iowrite64 and ioread64 for vfio pci
[ Upstream commit 2b938e3db335e3670475e31a722c2bee34748c5a ]
Definitions of ioread64 and iowrite64 macros in asm/io.h called by vfio
pci implementations are enclosed inside check for CONFIG_GENERIC_IOMAP.
They don't get defined if CONFIG_GENERIC_IOMAP is defined. Include
linux/io-64-nonatomic-lo-hi.h to define iowrite64 and ioread64 macros
when they are not defined. io-64-nonatomic-lo-hi.h maps the macros to
generic implementation in lib/iomap.c. The generic implementation does
64 bit rw if readq/writeq is defined for the architecture, otherwise it
would do 32 bit back to back rw.
Note that there are two versions of the generic implementation that
differs in the order the 32 bit words are written if 64 bit support is
not present. This is not the little/big endian ordering, which is
handled separately. This patch uses the lo followed by hi word ordering
which is consistent with current back to back implementation in the
vfio/pci code.
Signed-off-by: Ramesh Thomas <ramesh.thomas@xxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20241210131938.303500-2-ramesh.thomas@xxxxxxxxx
Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/vfio/pci/vfio_pci_rdwr.c b/drivers/vfio/pci/vfio_pci_rdwr.c
index 83f81d24df78e..94e3fb9f42243 100644
--- a/drivers/vfio/pci/vfio_pci_rdwr.c
+++ b/drivers/vfio/pci/vfio_pci_rdwr.c
@@ -16,6 +16,7 @@
#include <linux/io.h>
#include <linux/vfio.h>
#include <linux/vgaarb.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
#include "vfio_pci_private.h"
