Merge tag 'vfio-v7.3-rc1' of https://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Add nv_falcon vfio selftest driver.

   The Falcon is a general-purpose microcontroller embedded within
   NVIDIA GPUs, presenting a relatively simple DMA programming
   interface.

   This adds another selftest target for vfio-pci with real DMA
   transfers (Rubin Du, Alex Williamson)

 - Add allocation assertion helpers to vfio selftests and use them to
   avoid variable length arrays and the compiler errors they generate
   (Alex Mastro)

 - Fix use-after-free hazard where an init path error in MSI support
   leaves a stray pointer that can later be reused or double-freed
   (Xiang Mei)

 - Fix previous refactor of PCI BAR mappings to honor non_mappable_bars
   flag, which otherwise generates a warning when trying to pci_iomap()
   a 256TiB BAR on ISM devices on s390 (Farhan Ali)

 - Add igb vfio selftest driver.

   Like nv_falcon, this provides another target for DMA testing with
   vfio selftests, but importantly this driver supports both physical
   82576 NICs and the emulation model in QEMU.

   This therefore enables a vfio selftest vector with no physical
   hardware requirements (Josh Hilke, Alex Williamson)

 - Mark selftest fixture objects __maybe_unused to accommodate builds
   with clang -Wunused-but-set-global (David Matlack)

 - Add error recovery for vfio-pci devices on s390x.

   This expands devices which expose the existing error eventfd and
   introduces a device feature for reporting firmware defined error
   state information to the user, allowing recovery through hypervisor
   channels (Farhan Ali)

* tag 'vfio-v7.3-rc1' of https://github.com/awilliam/linux-vfio:
  vfio/pci: Remove the pcie check for VFIO_PCI_ERR_IRQ_INDEX
  vfio-pci/zdev: Add a device feature for error information
  s390/pci: Store PCI error information for passthrough devices
  PCI/MSI: Enable memory decoding before restoring MSI-X messages
  PCI: Fail FLR when config space is inaccessible
  PCI: Avoid saving config space state if inaccessible
  PCI: Allow per function PCI slots to fix slot reset on s390
  PCI: Introduce PCI_SLOT_PLACEHOLDER constant for slot_nr placeholder value
  selftests: harness: Mark test fixture objects __maybe_unused
  vfio: selftests: Retry on EAGAIN during device reset
  vfio: selftests: igb: Add driver for Intel 82576 device
  vfio: selftests: Add helpers to re-enable interrupts
  vfio/pci: Avoid mapping BARs for devices with non-mappable BARs
  vfio/pci: clear vdev->msi_perm after freeing it on init failure
  vfio: selftests: Avoid VLAs
  vfio: selftests: Add allocation assert helpers
  vfio: selftests: Add NVIDIA Falcon driver for DMA testing
  vfio: selftests: Allow drivers without send_msi() support
  vfio: selftests: Add generic PCI command register helpers
  vfio: selftests: Add memcpy chunking to vfio_pci_driver_memcpy()

3 files changed, 29 insertions, 2 deletions

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 3d2c1ac645ff..c956bbf18ecc 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -79,14 +79,18 @@
  * and, if ARI Forwarding is enabled, functions may appear to be on multiple
  * devices.
  */
-#define PCI_SLOT_ALL_DEVICES	0xfe
+#define PCI_SLOT_ALL_DEVICES	0xfeff
+
+/* Used to identify a slot as a placeholder */
+#define PCI_SLOT_PLACEHOLDER	0xffff
 
 /* pci_slot represents a physical slot */
 struct pci_slot {
 	struct pci_bus		*bus;		/* Bus this slot is on */
 	struct list_head	list;		/* Node in list of slots */
 	struct hotplug_slot	*hotplug;	/* Hotplug info (move here) */
-	unsigned char		number;		/* Device nr, or PCI_SLOT_ALL_DEVICES */
+	u16			number;		/* Device nr, or PCI_SLOT_ALL_DEVICES */
+	unsigned int		per_func_slot:1; /* Allow per function slot */
 	struct kobject		kobj;
 };
 
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 5de618a3a5ee..e41437fa17ad 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -1534,6 +1534,27 @@ struct vfio_device_feature_dma_buf {
  */
 #define VFIO_DEVICE_FEATURE_MIG_PRECOPY_INFOv2  12
 
+/**
+ * VFIO_DEVICE_FEATURE_ZPCI_ERROR feature provides PCI error information to
+ * userspace for vfio-pci devices on s390. On s390, PCI error recovery
+ * involves platform firmware and notification to operating systems is done
+ * by architecture specific mechanism. Exposing this information to
+ * userspace allows it to take appropriate actions to handle an
+ * error on the device.
+ *
+ * Userspace provides an opaque buffer of fixed length, and the kernel
+ * fills it with the zpci_ccdf_err data structure. The length of
+ * zpci_ccdf_err is provided to userspace via the
+ * VFIO_DEVICE_INFO_CAP_ZPCI_BASE capability.
+ *
+ * The ioctl returns -ENOMSG if there are no pending PCI errors.
+ */
+struct vfio_device_feature_zpci_err {
+	__aligned_u64 data;
+};
+
+#define VFIO_DEVICE_FEATURE_ZPCI_ERROR 13
+
 /* -------- API for Type1 VFIO IOMMU -------- */
 
 /**
diff --git a/include/uapi/linux/vfio_zdev.h b/include/uapi/linux/vfio_zdev.h
index 77f2aff1f27e..d6c1175c884e 100644
--- a/include/uapi/linux/vfio_zdev.h
+++ b/include/uapi/linux/vfio_zdev.h
@@ -32,6 +32,8 @@ struct vfio_device_info_cap_zpci_base {
 	/* End of version 1 */
 	__u32 fh;		/* PCI function handle */
 	/* End of version 2 */
+	__u32 ccdf_err_length;	/* PCI CCDF length */
+	/* End of version 3 */
 };
 
 /**