[RFC PATCH 7/9] i40e/vf_migration: register mediate_ops to vfio-pci

Yan Zhao
2019-12-05T03:35:47Z

register to vfio-pci vfio_pci_mediate_ops when i40e binds to PF to
support mediating of VF's vfio-pci ops.
unregister vfio_pci_mediate_ops when i40e unbinds from PF.

vfio_pci_mediate_ops->open will return success if the device passed in
equals to devfn of its VFs

Cc: Shaopeng He <shaopeng.he@intel.com>

Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
---
drivers/net/ethernet/intel/Kconfig | 2 +-
drivers/net/ethernet/intel/i40e/Makefile | 3 +-
drivers/net/ethernet/intel/i40e/i40e.h | 2 +
drivers/net/ethernet/intel/i40e/i40e_main.c | 3 +
.../ethernet/intel/i40e/i40e_vf_migration.c | 169 ++++++++++++++++++
.../ethernet/intel/i40e/i40e_vf_migration.h | 52 ++++++
6 files changed, 229 insertions(+), 2 deletions(-)
create mode 100644 drivers/net/ethernet/intel/i40e/i40e_vf_migration.c
create mode 100644 drivers/net/ethernet/intel/i40e/i40e_vf_migration.h

diff --git a/drivers/net/ethernet/intel/Kconfig b/drivers/net/ethernet/intel/Kconfig
index 154e2e818ec6..b5c7fdf55380 100644
--- a/drivers/net/ethernet/intel/Kconfig
+++ b/drivers/net/ethernet/intel/Kconfig
@@ -240,7 +240,7 @@ config IXGBEVF_IPSEC
config I40E
tristate "Intel(R) Ethernet Controller XL710 Family support"
imply PTP_1588_CLOCK
- depends on PCI
+ depends on PCI && VFIO_PCI
---help---
This driver supports Intel(R) Ethernet Controller XL710 Family of
devices. For more information on how to identify your adapter, go
diff --git a/drivers/net/ethernet/intel/i40e/Makefile b/drivers/net/ethernet/intel/i40e/Makefile
index 2f21b3e89fd0..ae7a6a23dba9 100644
--- a/drivers/net/ethernet/intel/i40e/Makefile
+++ b/drivers/net/ethernet/intel/i40e/Makefile
@@ -24,6 +24,7 @@ i40e-objs := i40e_main.o \
i40e_ddp.o \
i40e_client.o \
i40e_virtchnl_pf.o \
- i40e_xsk.o
+ i40e_xsk.o \
+ i40e_vf_migration.o

i40e-$(CONFIG_I40E_DCB) += i40e_dcb.o i40e_dcb_nl.o
diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 2af9f6308f84..0141c94b835f 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -1162,4 +1162,6 @@ int i40e_add_del_cloud_filter(struct i40e_vsi *vsi,
int i40e_add_del_cloud_filter_big_buf(struct i40e_vsi *vsi,
struct i40e_cloud_filter *filter,
bool add);
+int i40e_vf_migration_register(void);
+void i40e_vf_migration_unregister(void);
#endif /* _I40E_H_ */
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 6031223eafab..92d1c3fdc808 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -15274,6 +15274,7 @@ static int i40e_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
/* print a string summarizing features */
i40e_print_features(pf);

+ i40e_vf_migration_register();
return 0;

/* Unwind what we've done if something failed in the setup */
@@ -15320,6 +15321,8 @@ static void i40e_remove(struct pci_dev *pdev)
i40e_status ret_code;
int i;

+ i40e_vf_migration_unregister();
+
i40e_dbg_pf_exit(pf);

i40e_ptp_stop(pf);
diff --git a/drivers/net/ethernet/intel/i40e/i40e_vf_migration.c b/drivers/net/ethernet/intel/i40e/i40e_vf_migration.c
new file mode 100644
index 000000000000..b2d913459600
--- /dev/null
+++ b/drivers/net/ethernet/intel/i40e/i40e_vf_migration.c
@@ -0,0 +1,169 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2013 - 2019 Intel Corporation. */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/vfio.h>
+#include <linux/pci.h>
+#include <linux/eventfd.h>
+
+#include "i40e.h"
+#include "i40e_vf_migration.h"
+
+static long open_device_bits[MAX_OPEN_DEVICE / BITS_PER_LONG + 1];
+static DEFINE_MUTEX(device_bit_lock);
+static struct i40e_vf_migration *i40e_vf_dev_array[MAX_OPEN_DEVICE];
+
+int i40e_vf_migration_open(struct pci_dev *pdev, u64 *caps, u32 *dm_handle)
+{
+ int i, ret = 0;
+ struct i40e_vf_migration *i40e_vf_dev = NULL;
+ int handle;
+ struct pci_dev *pf_dev, *vf_dev;
+ struct i40e_pf *pf;
+ struct i40e_vf *vf;
+ unsigned int vf_devfn, devfn;
+ int vf_id = -1;
+
+ if (!try_module_get(THIS_MODULE))
+ return -ENODEV;
+
+ pf_dev = pdev->physfn;
+ pf = pci_get_drvdata(pf_dev);
+ vf_dev = pdev;
+ vf_devfn = vf_dev->devfn;
+
+ for (i = 0; i < pci_num_vf(pf_dev); i++) {
+ devfn = (pf_dev->devfn + pf_dev->sriov->offset +
+ pf_dev->sriov->stride * i) & 0xff;
+ if (devfn == vf_devfn) {
+ vf_id = i;
+ break;
+ }
+ }
+
+ if (vf_id == -1) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ mutex_lock(&device_bit_lock);
+ handle = find_next_zero_bit(open_device_bits, MAX_OPEN_DEVICE, 0);
+ if (handle >= MAX_OPEN_DEVICE) {
+ ret = -EBUSY;
+ goto error;
+ }
+
+ i40e_vf_dev = kzalloc(sizeof(*i40e_vf_dev), GFP_KERNEL);
+
+ if (!i40e_vf_dev) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ i40e_vf_dev->vf_id = vf_id;
+ i40e_vf_dev->vf_vendor = pdev->vendor;
+ i40e_vf_dev->vf_device = pdev->device;
+ i40e_vf_dev->pf_dev = pf_dev;
+ i40e_vf_dev->vf_dev = vf_dev;
+ i40e_vf_dev->handle = handle;
+
+ pr_info("%s: device %x %x, vf id %d, handle=%x\n",
+ __func__, pdev->vendor, pdev->device, vf_id, handle);
+
+ i40e_vf_dev_array[handle] = i40e_vf_dev;
+ set_bit(handle, open_device_bits);
+ vf = &pf->vf[vf_id];
+ *dm_handle = handle;
+error:
+ mutex_unlock(&device_bit_lock);
+
+ if (ret < 0) {
+ module_put(THIS_MODULE);
+ kfree(i40e_vf_dev);
+ }
+
+out:
+ return ret;
+}
+
+void i40e_vf_migration_release(int handle)
+{
+ struct i40e_vf_migration *i40e_vf_dev;
+
+ mutex_lock(&device_bit_lock);
+
+ if (handle >= MAX_OPEN_DEVICE ||
+ !i40e_vf_dev_array[handle] ||
+ !test_bit(handle, open_device_bits)) {
+ pr_err("handle mismatch, please check interaction with vfio-pci module\n");
+ mutex_unlock(&device_bit_lock);
+ return;
+ }
+
+ i40e_vf_dev = i40e_vf_dev_array[handle];
+ i40e_vf_dev_array[handle] = NULL;
+
+ clear_bit(handle, open_device_bits);
+ mutex_unlock(&device_bit_lock);
+
+ pr_info("%s: handle=%d, i40e_vf_dev VID DID =%x %x, vf id=%d\n",
+ __func__, handle,
+ i40e_vf_dev->vf_vendor, i40e_vf_dev->vf_device,
+ i40e_vf_dev->vf_id);
+
+ kfree(i40e_vf_dev);
+ module_put(THIS_MODULE);
+}
+
+static void
+i40e_vf_migration_get_region_info(int handle,
+ struct vfio_region_info *info,
+ struct vfio_info_cap *caps,
+ struct vfio_region_info_cap_type *cap_type)
+{
+}
+
+static ssize_t i40e_vf_migration_rw(int handle, char __user *buf,
+ size_t count, loff_t *ppos,
+ bool iswrite, bool *pt)
+{
+ *pt = true;
+
+ return 0;
+}
+
+static int i40e_vf_migration_mmap(int handle, struct vm_area_struct *vma,
+ bool *pt)
+{
+ *pt = true;
+ return 0;
+}
+
+static struct vfio_pci_mediate_ops i40e_vf_migration_ops = {
+ .name = "i40e_vf",
+ .open = i40e_vf_migration_open,
+ .release = i40e_vf_migration_release,
+ .get_region_info = i40e_vf_migration_get_region_info,
+ .rw = i40e_vf_migration_rw,
+ .mmap = i40e_vf_migration_mmap,
+};
+
+int i40e_vf_migration_register(void)
+{
+ int ret = 0;
+
+ pr_info("%s\n", __func__);
+
+ memset(open_device_bits, 0, sizeof(open_device_bits));
+ memset(i40e_vf_dev_array, 0, sizeof(i40e_vf_dev_array));
+ vfio_pci_register_mediate_ops(&i40e_vf_migration_ops);
+
+ return ret;
+}
+
+void i40e_vf_migration_unregister(void)
+{
+ pr_info("%s\n", __func__);
+ vfio_pci_unregister_mediate_ops(&i40e_vf_migration_ops);
+}
diff --git a/drivers/net/ethernet/intel/i40e/i40e_vf_migration.h b/drivers/net/ethernet/intel/i40e/i40e_vf_migration.h
new file mode 100644
index 000000000000..b195399b6788
--- /dev/null
+++ b/drivers/net/ethernet/intel/i40e/i40e_vf_migration.h
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright(c) 2013 - 2019 Intel Corporation. */
+
+#ifndef I40E_MIG_H
+#define I40E_MIG_H
+
+#include <linux/pci.h>
+#include <linux/vfio.h>
+#include <linux/mdev.h>
+
+#include "i40e.h"
+#include "i40e_txrx.h"
+
+#define MAX_OPEN_DEVICE 1024
+
+/* Single Root I/O Virtualization */
+struct pci_sriov {
+ int pos; /* Capability position */
+ int nres; /* Number of resources */
+ u32 cap; /* SR-IOV Capabilities */
+ u16 ctrl; /* SR-IOV Control */
+ u16 total_VFs; /* Total VFs associated with the PF */
+ u16 initial_VFs; /* Initial VFs associated with the PF */
+ u16 num_VFs; /* Number of VFs available */
+ u16 offset; /* First VF Routing ID offset */
+ u16 stride; /* Following VF stride */
+ u16 vf_device; /* VF device ID */
+ u32 pgsz; /* Page size for BAR alignment */
+ u8 link; /* Function Dependency Link */
+ u8 max_VF_buses; /* Max buses consumed by VFs */
+ u16 driver_max_VFs; /* Max num VFs driver supports */
+ struct pci_dev *dev; /* Lowest numbered PF */
+ struct pci_dev *self; /* This PF */
+ u32 cfg_size; /* VF config space size */
+ u32 class; /* VF device */
+ u8 hdr_type; /* VF header type */
+ u16 subsystem_vendor; /* VF subsystem vendor */
+ u16 subsystem_device; /* VF subsystem device */
+ resource_size_t barsz[PCI_SRIOV_NUM_BARS]; /* VF BAR size */
+ bool drivers_autoprobe; /* Auto probing of VFs by driver */
+};
+
+struct i40e_vf_migration {
+ __u32 vf_vendor;
+ __u32 vf_device;
+ __u32 handle;
+ struct pci_dev *pf_dev;
+ struct pci_dev *vf_dev;
+ int vf_id;
+};
+#endif /* I40E_MIG_H */
+
--
2.17.1