Merge tag 'vfio-v6.6-rc1' of https://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - VFIO direct character device (cdev) interface support. This extracts
   the vfio device fd from the container and group model, and is
   intended to be the native uAPI for use with IOMMUFD (Yi Liu)

 - Enhancements to the PCI hot reset interface in support of cdev usage
   (Yi Liu)

 - Fix a potential race between registering and unregistering vfio files
   in the kvm-vfio interface and extend use of a lock to avoid extra
   drop and acquires (Dmitry Torokhov)

 - A new vfio-pci variant driver for the AMD/Pensando Distributed
   Services Card (PDS) Ethernet device, supporting live migration (Brett
   Creeley)

 - Cleanups to remove redundant owner setup in cdx and fsl bus drivers,
   and simplify driver init/exit in fsl code (Li Zetao)

 - Fix uninitialized hole in data structure and pad capability
   structures for alignment (Stefan Hajnoczi)

* tag 'vfio-v6.6-rc1' of https://github.com/awilliam/linux-vfio: (53 commits)
  vfio/pds: Send type for SUSPEND_STATUS command
  vfio/pds: fix return value in pds_vfio_get_lm_file()
  pds_core: Fix function header descriptions
  vfio: align capability structures
  vfio/type1: fix cap_migration information leak
  vfio/fsl-mc: Use module_fsl_mc_driver macro to simplify the code
  vfio/cdx: Remove redundant initialization owner in vfio_cdx_driver
  vfio/pds: Add Kconfig and documentation
  vfio/pds: Add support for firmware recovery
  vfio/pds: Add support for dirty page tracking
  vfio/pds: Add VFIO live migration support
  vfio/pds: register with the pds_core PF
  pds_core: Require callers of register/unregister to pass PF drvdata
  vfio/pds: Initial support for pds VFIO driver
  vfio: Commonize combine_ranges for use in other VFIO drivers
  kvm/vfio: avoid bouncing the mutex when adding and deleting groups
  kvm/vfio: ensure kvg instance stays around in kvm_vfio_group_add()
  docs: vfio: Add vfio device cdev description
  vfio: Compile vfio_group infrastructure optionally
  vfio: Move the IOMMU_CAP_CACHE_COHERENCY check in __vfio_register_dev()
  ...

1 files changed, 227 insertions, 0 deletions

diff --git a/drivers/vfio/pci/pds/vfio_dev.c b/drivers/vfio/pci/pds/vfio_dev.c
new file mode 100644
index 000000000000..b46174f5eb09
--- /dev/null
+++ b/drivers/vfio/pci/pds/vfio_dev.c
@@ -0,0 +1,227 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2023 Advanced Micro Devices, Inc. */
+
+#include <linux/vfio.h>
+#include <linux/vfio_pci_core.h>
+
+#include "lm.h"
+#include "dirty.h"
+#include "vfio_dev.h"
+
+struct pci_dev *pds_vfio_to_pci_dev(struct pds_vfio_pci_device *pds_vfio)
+{
+	return pds_vfio->vfio_coredev.pdev;
+}
+
+struct device *pds_vfio_to_dev(struct pds_vfio_pci_device *pds_vfio)
+{
+	return &pds_vfio_to_pci_dev(pds_vfio)->dev;
+}
+
+struct pds_vfio_pci_device *pds_vfio_pci_drvdata(struct pci_dev *pdev)
+{
+	struct vfio_pci_core_device *core_device = dev_get_drvdata(&pdev->dev);
+
+	return container_of(core_device, struct pds_vfio_pci_device,
+			    vfio_coredev);
+}
+
+void pds_vfio_state_mutex_unlock(struct pds_vfio_pci_device *pds_vfio)
+{
+again:
+	spin_lock(&pds_vfio->reset_lock);
+	if (pds_vfio->deferred_reset) {
+		pds_vfio->deferred_reset = false;
+		if (pds_vfio->state == VFIO_DEVICE_STATE_ERROR) {
+			pds_vfio_put_restore_file(pds_vfio);
+			pds_vfio_put_save_file(pds_vfio);
+			pds_vfio_dirty_disable(pds_vfio, false);
+		}
+		pds_vfio->state = pds_vfio->deferred_reset_state;
+		pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_RUNNING;
+		spin_unlock(&pds_vfio->reset_lock);
+		goto again;
+	}
+	mutex_unlock(&pds_vfio->state_mutex);
+	spin_unlock(&pds_vfio->reset_lock);
+}
+
+void pds_vfio_reset(struct pds_vfio_pci_device *pds_vfio)
+{
+	spin_lock(&pds_vfio->reset_lock);
+	pds_vfio->deferred_reset = true;
+	pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_RUNNING;
+	if (!mutex_trylock(&pds_vfio->state_mutex)) {
+		spin_unlock(&pds_vfio->reset_lock);
+		return;
+	}
+	spin_unlock(&pds_vfio->reset_lock);
+	pds_vfio_state_mutex_unlock(pds_vfio);
+}
+
+static struct file *
+pds_vfio_set_device_state(struct vfio_device *vdev,
+			  enum vfio_device_mig_state new_state)
+{
+	struct pds_vfio_pci_device *pds_vfio =
+		container_of(vdev, struct pds_vfio_pci_device,
+			     vfio_coredev.vdev);
+	struct file *res = NULL;
+
+	mutex_lock(&pds_vfio->state_mutex);
+	/*
+	 * only way to transition out of VFIO_DEVICE_STATE_ERROR is via
+	 * VFIO_DEVICE_RESET, so prevent the state machine from running since
+	 * vfio_mig_get_next_state() will throw a WARN_ON() when transitioning
+	 * from VFIO_DEVICE_STATE_ERROR to any other state
+	 */
+	while (pds_vfio->state != VFIO_DEVICE_STATE_ERROR &&
+	       new_state != pds_vfio->state) {
+		enum vfio_device_mig_state next_state;
+
+		int err = vfio_mig_get_next_state(vdev, pds_vfio->state,
+						  new_state, &next_state);
+		if (err) {
+			res = ERR_PTR(err);
+			break;
+		}
+
+		res = pds_vfio_step_device_state_locked(pds_vfio, next_state);
+		if (IS_ERR(res))
+			break;
+
+		pds_vfio->state = next_state;
+
+		if (WARN_ON(res && new_state != pds_vfio->state)) {
+			res = ERR_PTR(-EINVAL);
+			break;
+		}
+	}
+	pds_vfio_state_mutex_unlock(pds_vfio);
+	/* still waiting on a deferred_reset */
+	if (pds_vfio->state == VFIO_DEVICE_STATE_ERROR)
+		res = ERR_PTR(-EIO);
+
+	return res;
+}
+
+static int pds_vfio_get_device_state(struct vfio_device *vdev,
+				     enum vfio_device_mig_state *current_state)
+{
+	struct pds_vfio_pci_device *pds_vfio =
+		container_of(vdev, struct pds_vfio_pci_device,
+			     vfio_coredev.vdev);
+
+	mutex_lock(&pds_vfio->state_mutex);
+	*current_state = pds_vfio->state;
+	pds_vfio_state_mutex_unlock(pds_vfio);
+	return 0;
+}
+
+static int pds_vfio_get_device_state_size(struct vfio_device *vdev,
+					  unsigned long *stop_copy_length)
+{
+	*stop_copy_length = PDS_LM_DEVICE_STATE_LENGTH;
+	return 0;
+}
+
+static const struct vfio_migration_ops pds_vfio_lm_ops = {
+	.migration_set_state = pds_vfio_set_device_state,
+	.migration_get_state = pds_vfio_get_device_state,
+	.migration_get_data_size = pds_vfio_get_device_state_size
+};
+
+static const struct vfio_log_ops pds_vfio_log_ops = {
+	.log_start = pds_vfio_dma_logging_start,
+	.log_stop = pds_vfio_dma_logging_stop,
+	.log_read_and_clear = pds_vfio_dma_logging_report,
+};
+
+static int pds_vfio_init_device(struct vfio_device *vdev)
+{
+	struct pds_vfio_pci_device *pds_vfio =
+		container_of(vdev, struct pds_vfio_pci_device,
+			     vfio_coredev.vdev);
+	struct pci_dev *pdev = to_pci_dev(vdev->dev);
+	int err, vf_id, pci_id;
+
+	vf_id = pci_iov_vf_id(pdev);
+	if (vf_id < 0)
+		return vf_id;
+
+	err = vfio_pci_core_init_dev(vdev);
+	if (err)
+		return err;
+
+	pds_vfio->vf_id = vf_id;
+
+	vdev->migration_flags = VFIO_MIGRATION_STOP_COPY | VFIO_MIGRATION_P2P;
+	vdev->mig_ops = &pds_vfio_lm_ops;
+	vdev->log_ops = &pds_vfio_log_ops;
+
+	pci_id = PCI_DEVID(pdev->bus->number, pdev->devfn);
+	dev_dbg(&pdev->dev,
+		"%s: PF %#04x VF %#04x vf_id %d domain %d pds_vfio %p\n",
+		__func__, pci_dev_id(pdev->physfn), pci_id, vf_id,
+		pci_domain_nr(pdev->bus), pds_vfio);
+
+	return 0;
+}
+
+static int pds_vfio_open_device(struct vfio_device *vdev)
+{
+	struct pds_vfio_pci_device *pds_vfio =
+		container_of(vdev, struct pds_vfio_pci_device,
+			     vfio_coredev.vdev);
+	int err;
+
+	err = vfio_pci_core_enable(&pds_vfio->vfio_coredev);
+	if (err)
+		return err;
+
+	mutex_init(&pds_vfio->state_mutex);
+	pds_vfio->state = VFIO_DEVICE_STATE_RUNNING;
+	pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_RUNNING;
+
+	vfio_pci_core_finish_enable(&pds_vfio->vfio_coredev);
+
+	return 0;
+}
+
+static void pds_vfio_close_device(struct vfio_device *vdev)
+{
+	struct pds_vfio_pci_device *pds_vfio =
+		container_of(vdev, struct pds_vfio_pci_device,
+			     vfio_coredev.vdev);
+
+	mutex_lock(&pds_vfio->state_mutex);
+	pds_vfio_put_restore_file(pds_vfio);
+	pds_vfio_put_save_file(pds_vfio);
+	pds_vfio_dirty_disable(pds_vfio, true);
+	mutex_unlock(&pds_vfio->state_mutex);
+	mutex_destroy(&pds_vfio->state_mutex);
+	vfio_pci_core_close_device(vdev);
+}
+
+static const struct vfio_device_ops pds_vfio_ops = {
+	.name = "pds-vfio",
+	.init = pds_vfio_init_device,
+	.release = vfio_pci_core_release_dev,
+	.open_device = pds_vfio_open_device,
+	.close_device = pds_vfio_close_device,
+	.ioctl = vfio_pci_core_ioctl,
+	.device_feature = vfio_pci_core_ioctl_feature,
+	.read = vfio_pci_core_read,
+	.write = vfio_pci_core_write,
+	.mmap = vfio_pci_core_mmap,
+	.request = vfio_pci_core_request,
+	.match = vfio_pci_core_match,
+	.bind_iommufd = vfio_iommufd_physical_bind,
+	.unbind_iommufd = vfio_iommufd_physical_unbind,
+	.attach_ioas = vfio_iommufd_physical_attach_ioas,
+};
+
+const struct vfio_device_ops *pds_vfio_ops_info(void)
+{
+	return &pds_vfio_ops;
+}