[AMD Official Use Only - General]
> -----Original Message-----
> From: Alex Williamson <alex.williamson@redhat.com>
> Sent: Monday, April 17, 2023 7:51 PM
> To: Gupta, Nipun <Nipun.Gupta@amd.com>
> Cc: jgg@ziepe.ca; linux-kernel@vger.kernel.org; kvm@vger.kernel.org;
> masahiroy@kernel.org; nathan@kernel.org; ndesaulniers@google.com;
> nicolas@fjasle.eu; git (AMD-Xilinx) <git@amd.com>; Anand, Harpreet
> <harpreet.anand@amd.com>; Jansen Van Vuuren, Pieter <pieter.jansen-
> van-vuuren@amd.com>; Agarwal, Nikhil <nikhil.agarwal@amd.com>; Simek,
> Michal <michal.simek@amd.com>
> Subject: Re: [PATCH v3] vfio/cdx: add support for CDX bus
>
> Caution: This message originated from an External Source. Use proper
> caution when opening attachments, clicking links, or responding.
>
>
> On Mon, 17 Apr 2023 14:07:25 +0530
> Nipun Gupta <nipun.gupta@amd.com> wrote:
>
> > +static long vfio_cdx_ioctl(struct vfio_device *core_vdev,
> > + unsigned int cmd, unsigned long arg)
> > +{
> > + struct vfio_cdx_device *vdev =
> > + container_of(core_vdev, struct vfio_cdx_device, vdev);
> > + struct cdx_device *cdx_dev = to_cdx_device(core_vdev->dev);
> > + unsigned long minsz;
> > +
> > + switch (cmd) {
> > + case VFIO_DEVICE_GET_INFO:
> > + {
> > + struct vfio_device_info info;
> > +
> > + minsz = offsetofend(struct vfio_device_info, num_irqs);
> > +
> > + if (copy_from_user(&info, (void __user *)arg, minsz))
> > + return -EFAULT;
> > +
> > + if (info.argsz < minsz)
> > + return -EINVAL;
> > +
> > + info.flags = VFIO_DEVICE_FLAGS_CDX;
> > + info.flags = VFIO_DEVICE_FLAGS_RESET;
>
> Whoops, I think you mean |= for the latter one. Thanks,
Oh!! Will send a quick v4 fixing this.
Thanks,
Nipun
>
> Alex
@@ -22064,6 +22064,13 @@ F: Documentation/filesystems/vfat.rst
F: fs/fat/
F: tools/testing/selftests/filesystems/fat/
+VFIO CDX DRIVER
+M: Nipun Gupta <nipun.gupta@amd.com>
+M: Nikhil Agarwal <nikhil.agarwal@amd.com>
+L: kvm@vger.kernel.org
+S: Maintained
+F: drivers/vfio/cdx/*
+
VFIO DRIVER
M: Alex Williamson <alex.williamson@redhat.com>
L: kvm@vger.kernel.org
@@ -57,6 +57,7 @@ source "drivers/vfio/pci/Kconfig"
source "drivers/vfio/platform/Kconfig"
source "drivers/vfio/mdev/Kconfig"
source "drivers/vfio/fsl-mc/Kconfig"
+source "drivers/vfio/cdx/Kconfig"
endif
source "virt/lib/Kconfig"
@@ -14,3 +14,4 @@ obj-$(CONFIG_VFIO_PCI) += pci/
obj-$(CONFIG_VFIO_PLATFORM) += platform/
obj-$(CONFIG_VFIO_MDEV) += mdev/
obj-$(CONFIG_VFIO_FSL_MC) += fsl-mc/
+obj-$(CONFIG_VFIO_CDX) += cdx/
new file mode 100644
@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# VFIO CDX configuration
+#
+# Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
+#
+
+config VFIO_CDX
+ tristate "VFIO support for CDX bus devices"
+ depends on CDX_BUS
+ select EVENTFD
+ help
+ Driver to enable VFIO support for the devices on CDX bus.
+ This is required to make use of CDX devices present in
+ the system using the VFIO framework.
+
+ If you don't know what to do here, say N.
new file mode 100644
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
+#
+
+obj-$(CONFIG_VFIO_CDX) += vfio-cdx.o
+
+vfio-cdx-objs := vfio_cdx.o
new file mode 100644
@@ -0,0 +1,271 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
+ */
+
+#include <linux/vfio.h>
+#include <linux/cdx/cdx_bus.h>
+
+#include "vfio_cdx_private.h"
+
+static struct cdx_driver vfio_cdx_driver;
+
+/**
+ * CDX_DRIVER_OVERRIDE_DEVICE_VFIO - macro used to describe a VFIO
+ * "driver_override" CDX device.
+ * @vend: the 16 bit CDX Vendor ID
+ * @dev: the 16 bit CDX Device ID
+ *
+ * This macro is used to create a struct cdx_device_id that matches a
+ * specific device. driver_override will be set to
+ * CDX_ID_F_VFIO_DRIVER_OVERRIDE.
+ */
+#define CDX_DRIVER_OVERRIDE_DEVICE_VFIO(vend, dev) \
+ CDX_DEVICE_DRIVER_OVERRIDE(vend, dev, CDX_ID_F_VFIO_DRIVER_OVERRIDE)
+
+static int vfio_cdx_open_device(struct vfio_device *core_vdev)
+{
+ struct vfio_cdx_device *vdev =
+ container_of(core_vdev, struct vfio_cdx_device, vdev);
+ struct cdx_device *cdx_dev = to_cdx_device(core_vdev->dev);
+ int count = cdx_dev->res_count;
+ int i;
+
+ vdev->regions = kcalloc(count, sizeof(struct vfio_cdx_region),
+ GFP_KERNEL);
+ if (!vdev->regions)
+ return -ENOMEM;
+
+ for (i = 0; i < count; i++) {
+ struct resource *res = &cdx_dev->res[i];
+
+ vdev->regions[i].addr = res->start;
+ vdev->regions[i].size = resource_size(res);
+ vdev->regions[i].type = res->flags;
+ /*
+ * Only regions addressed with PAGE granularity may be
+ * MMAP'ed securely.
+ */
+ if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
+ !(vdev->regions[i].size & ~PAGE_MASK))
+ vdev->regions[i].flags |=
+ VFIO_REGION_INFO_FLAG_MMAP;
+ vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
+ if (!(cdx_dev->res[i].flags & IORESOURCE_READONLY))
+ vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_WRITE;
+ }
+
+ return 0;
+}
+
+static void vfio_cdx_regions_cleanup(struct vfio_cdx_device *vdev)
+{
+ kfree(vdev->regions);
+}
+
+static void vfio_cdx_close_device(struct vfio_device *core_vdev)
+{
+ struct vfio_cdx_device *vdev =
+ container_of(core_vdev, struct vfio_cdx_device, vdev);
+ int ret;
+
+ vfio_cdx_regions_cleanup(vdev);
+
+ /* reset the device before cleaning up the interrupts */
+ ret = cdx_dev_reset(core_vdev->dev);
+ if (ret)
+ dev_warn(core_vdev->dev,
+ "VFIO_CDX: reset device has failed (%d)\n", ret);
+}
+
+static long vfio_cdx_ioctl(struct vfio_device *core_vdev,
+ unsigned int cmd, unsigned long arg)
+{
+ struct vfio_cdx_device *vdev =
+ container_of(core_vdev, struct vfio_cdx_device, vdev);
+ struct cdx_device *cdx_dev = to_cdx_device(core_vdev->dev);
+ unsigned long minsz;
+
+ switch (cmd) {
+ case VFIO_DEVICE_GET_INFO:
+ {
+ struct vfio_device_info info;
+
+ minsz = offsetofend(struct vfio_device_info, num_irqs);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ info.flags = VFIO_DEVICE_FLAGS_CDX;
+ info.flags = VFIO_DEVICE_FLAGS_RESET;
+
+ info.num_regions = cdx_dev->res_count;
+ info.num_irqs = 0;
+
+ return copy_to_user((void __user *)arg, &info, minsz) ?
+ -EFAULT : 0;
+ }
+ case VFIO_DEVICE_GET_REGION_INFO:
+ {
+ struct vfio_region_info info;
+
+ minsz = offsetofend(struct vfio_region_info, offset);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ if (info.index >= cdx_dev->res_count)
+ return -EINVAL;
+
+ /* map offset to the physical address */
+ info.offset = vfio_cdx_index_to_offset(info.index);
+ info.size = vdev->regions[info.index].size;
+ info.flags = vdev->regions[info.index].flags;
+
+ if (copy_to_user((void __user *)arg, &info, minsz))
+ return -EFAULT;
+ return 0;
+ }
+ case VFIO_DEVICE_RESET:
+ {
+ return cdx_dev_reset(core_vdev->dev);
+ }
+ default:
+ return -ENOTTY;
+ }
+}
+
+static int vfio_cdx_mmap_mmio(struct vfio_cdx_region region,
+ struct vm_area_struct *vma)
+{
+ u64 size = vma->vm_end - vma->vm_start;
+ u64 pgoff, base;
+
+ pgoff = vma->vm_pgoff &
+ ((1U << (VFIO_CDX_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
+ base = pgoff << PAGE_SHIFT;
+
+ if (region.size < PAGE_SIZE || base + size > region.size)
+ return -EINVAL;
+
+ vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
+ vma->vm_page_prot = pgprot_device(vma->vm_page_prot);
+
+ return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+ size, vma->vm_page_prot);
+}
+
+static int vfio_cdx_mmap(struct vfio_device *core_vdev,
+ struct vm_area_struct *vma)
+{
+ struct vfio_cdx_device *vdev =
+ container_of(core_vdev, struct vfio_cdx_device, vdev);
+ struct cdx_device *cdx_dev = to_cdx_device(core_vdev->dev);
+ unsigned int index;
+
+ index = vma->vm_pgoff >> (VFIO_CDX_OFFSET_SHIFT - PAGE_SHIFT);
+
+ if (index >= cdx_dev->res_count)
+ return -EINVAL;
+
+ if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
+ return -EINVAL;
+
+ if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ) &&
+ (vma->vm_flags & VM_READ))
+ return -EINVAL;
+
+ if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE) &&
+ (vma->vm_flags & VM_WRITE))
+ return -EINVAL;
+
+ return vfio_cdx_mmap_mmio(vdev->regions[index], vma);
+}
+
+static const struct vfio_device_ops vfio_cdx_ops = {
+ .name = "vfio-cdx",
+ .open_device = vfio_cdx_open_device,
+ .close_device = vfio_cdx_close_device,
+ .ioctl = vfio_cdx_ioctl,
+ .mmap = vfio_cdx_mmap,
+ .bind_iommufd = vfio_iommufd_physical_bind,
+ .unbind_iommufd = vfio_iommufd_physical_unbind,
+ .attach_ioas = vfio_iommufd_physical_attach_ioas,
+};
+
+static int vfio_cdx_probe(struct cdx_device *cdx_dev)
+{
+ struct vfio_cdx_device *vdev = NULL;
+ struct device *dev = &cdx_dev->dev;
+ int ret;
+
+ vdev = vfio_alloc_device(vfio_cdx_device, vdev, dev,
+ &vfio_cdx_ops);
+ if (IS_ERR(vdev))
+ return PTR_ERR(vdev);
+
+ ret = vfio_register_group_dev(&vdev->vdev);
+ if (ret) {
+ dev_err(dev, "VFIO_CDX: Failed to add to vfio group\n");
+ goto out_uninit;
+ }
+
+ dev_set_drvdata(dev, vdev);
+ return 0;
+
+out_uninit:
+ vfio_put_device(&vdev->vdev);
+ return ret;
+}
+
+static int vfio_cdx_remove(struct cdx_device *cdx_dev)
+{
+ struct device *dev = &cdx_dev->dev;
+ struct vfio_cdx_device *vdev;
+
+ vdev = dev_get_drvdata(dev);
+ vfio_unregister_group_dev(&vdev->vdev);
+ vfio_put_device(&vdev->vdev);
+
+ return 0;
+}
+
+static const struct cdx_device_id vfio_cdx_table[] = {
+ { CDX_DRIVER_OVERRIDE_DEVICE_VFIO(CDX_ANY_ID, CDX_ANY_ID) }, /* match all by default */
+ {}
+};
+
+MODULE_DEVICE_TABLE(cdx, vfio_cdx_table);
+
+static struct cdx_driver vfio_cdx_driver = {
+ .probe = vfio_cdx_probe,
+ .remove = vfio_cdx_remove,
+ .match_id_table = vfio_cdx_table,
+ .driver = {
+ .name = "vfio-cdx",
+ .owner = THIS_MODULE,
+ },
+ .driver_managed_dma = true,
+};
+
+static int __init vfio_cdx_driver_init(void)
+{
+ return cdx_driver_register(&vfio_cdx_driver);
+}
+
+static void __exit vfio_cdx_driver_exit(void)
+{
+ cdx_driver_unregister(&vfio_cdx_driver);
+}
+
+module_init(vfio_cdx_driver_init);
+module_exit(vfio_cdx_driver_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("VFIO for CDX devices - User Level meta-driver");
new file mode 100644
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
+ */
+
+#ifndef VFIO_CDX_PRIVATE_H
+#define VFIO_CDX_PRIVATE_H
+
+#define VFIO_CDX_OFFSET_SHIFT 40
+
+static inline u64 vfio_cdx_index_to_offset(u32 index)
+{
+ return ((u64)(index) << VFIO_CDX_OFFSET_SHIFT);
+}
+
+struct vfio_cdx_region {
+ u32 flags;
+ u32 type;
+ u64 addr;
+ resource_size_t size;
+};
+
+struct vfio_cdx_device {
+ struct vfio_device vdev;
+ struct vfio_cdx_region *regions;
+};
+
+#endif /* VFIO_CDX_PRIVATE_H */
@@ -14,7 +14,6 @@
#include <linux/mod_devicetable.h>
#define MAX_CDX_DEV_RESOURCES 4
-#define CDX_ANY_ID (0xFFFF)
#define CDX_CONTROLLER_ID_SHIFT 4
#define CDX_BUS_NUM_MASK 0xF
@@ -912,6 +912,12 @@ struct ishtp_device_id {
kernel_ulong_t driver_data;
};
+#define CDX_ANY_ID (0xFFFF)
+
+enum {
+ CDX_ID_F_VFIO_DRIVER_OVERRIDE = 1,
+};
+
/**
* struct cdx_device_id - CDX device identifier
* @vendor: Vendor ID
@@ -213,6 +213,7 @@ struct vfio_device_info {
#define VFIO_DEVICE_FLAGS_AP (1 << 5) /* vfio-ap device */
#define VFIO_DEVICE_FLAGS_FSL_MC (1 << 6) /* vfio-fsl-mc device */
#define VFIO_DEVICE_FLAGS_CAPS (1 << 7) /* Info supports caps */
+#define VFIO_DEVICE_FLAGS_CDX (1 << 8) /* vfio-cdx device */
__u32 num_regions; /* Max region index + 1 */
__u32 num_irqs; /* Max IRQ index + 1 */
__u32 cap_offset; /* Offset within info struct of first cap */
@@ -265,6 +265,7 @@ int main(void)
DEVID(cdx_device_id);
DEVID_FIELD(cdx_device_id, vendor);
DEVID_FIELD(cdx_device_id, device);
+ DEVID_FIELD(cdx_device_id, override_only);
return 0;
}
@@ -1458,8 +1458,23 @@ static int do_cdx_entry(const char *filename, void *symval,
{
DEF_FIELD(symval, cdx_device_id, vendor);
DEF_FIELD(symval, cdx_device_id, device);
+ DEF_FIELD(symval, cdx_device_id, override_only);
- sprintf(alias, "cdx:v%08Xd%08Xd", vendor, device);
+ switch (override_only) {
+ case 0:
+ strcpy(alias, "cdx:");
+ break;
+ case CDX_ID_F_VFIO_DRIVER_OVERRIDE:
+ strcpy(alias, "vfio_cdx:");
+ break;
+ default:
+ warn("Unknown CDX driver_override alias %08X\n",
+ override_only);
+ return 0;
+ }
+
+ ADD(alias, "v", vendor != CDX_ANY_ID, vendor);
+ ADD(alias, "d", device != CDX_ANY_ID, device);
return 1;
}