[PATCH v8 0/5] add debugfs to migration driver

[PATCH v8 0/5] add debugfs to migration driver

[Longfang Liu]

Add a debugfs function to the migration driver in VFIO to provide
a step-by-step test function for the migration driver.

When the execution of live migration fails, the user can view the
status and data during the migration process separately from the
source and the destination, which is convenient for users to analyze
and locate problems.

Changes v7 -> v8
	Add support for platform devices.

Changes v6 -> v7
	Fix some code style issues.

Changes v5 -> v6
	Control the creation of debugfs through the CONFIG_DEBUG_FS.

Changes v4 -> v5
	Remove the newly added vfio_migration_ops and use seq_printf
	to optimize the implementation of debugfs.

Changes v3 -> v4
	Change the migration_debug_operate interface to debug_root file.

Changes v2 -> v3
	Extend the debugfs function from hisilicon device to vfio.

Changes v1 -> v2
	Change the registration method of root_debugfs to register
	with module initialization.

Longfang Liu (5):
  vfio/migration: Add debugfs to live migration driver
  hisi_acc_vfio_pci: extract public functions for container_of
  hisi_acc_vfio_pci: register debugfs for hisilicon migration driver
  Documentation: add debugfs description for vfio
  vfio: update live migration device status

 .../ABI/testing/debugfs-hisi-migration        |  28 ++
 Documentation/ABI/testing/debugfs-vfio        |  17 +
 drivers/vfio/Makefile                         |   2 +-
 .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 306 +++++++++++++++++-
 .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h    |  11 +
 drivers/vfio/pci/mlx5/main.c                  |   3 +
 drivers/vfio/vfio.h                           |  14 +
 drivers/vfio/vfio_debugfs.c                   |  82 +++++
 drivers/vfio/vfio_main.c                      |   5 +
 include/linux/vfio.h                          |   8 +
 10 files changed, 465 insertions(+), 11 deletions(-)
 create mode 100644 Documentation/ABI/testing/debugfs-hisi-migration
 create mode 100644 Documentation/ABI/testing/debugfs-vfio
 create mode 100644 drivers/vfio/vfio_debugfs.c

-- 
2.24.0

[PATCH v8 1/5] vfio/migration: Add debugfs to live migration driver

[Longfang Liu]

There are multiple devices, software and operational steps involved
in the process of live migration. An error occurred on any node may
cause the live migration operation to fail.
This complex process makes it very difficult to locate and analyze
the cause when the function fails.

In order to quickly locate the cause of the problem when the
live migration fails, I added a set of debugfs to the vfio
live migration driver.
                               +-------------------------------------------+
                               |                                           |
                               |                                           |
                               |                  QEMU                     |
                               |                                           |
                               |                                           |
                               +---+----------------------------+----------+
                                   |      ^                     |      ^
                                   |      |                     |      |
 +--------+                        |      |                     |      |
 |  vfio  |                        v      |                     v      |
 +--------+                     +---------+--+               +---------+--+
     ^                          |src vfio_dev|               |dst vfio_dev|
     |                          +--+---------+               +--+---------+
     |                             |      ^                     |      ^
     |                             |      |                     |      |
     |                             v      |                     |      |
     |  +-----------+         +-----------+----+                |      |
     +--+<bdf>file_x+<----+---+migration_attr  |                |      |
     |  +-----------+     |   +----------------+                |      |
     |                    +---+migration_data  |                |      |
     |                    |   +----------------+                |      |
     |                    +---+migration_debug |                |      |
     |                    |   +----------------+                |      |
     |                    |   +----------------+                |      |
     |                    +---+migration_state |                |      |
     |                        +----------------+                |      |
     |                                                          |      |
     |  +-----------+         +----------------+                |      |
     +--+<bdf>file_y|<----+---+migration_attr  |                |      |
        +-----------+     |   +----------------+                |      |
                          +---+migration_data  |                |      |
                          |   +----------------+<---------------+      |
                          +---+migration_debug |                       |
                          |   +----------------+                       |
                          |   +----------------+                       |
                          +---+migration_state +-----------------------+
                              +----------------+

The entire debugfs directory will be based on the definition of
the CONFIG_DEBUG_FS macro. If this macro is not enabled, the
interfaces in vfio.h will be empty definitions, and the creation
and initialization of the debugfs directory will not be executed.

debugfs will create a public root directory "vfio" file.
then create a device <bdf> named file for each live migration device.
First, create a unified state acquisition file of "migration_state"
in this device directory.
Then, create your own debugging files independently according to
the functional requirements of each device.

Here, HiSilicon accelerator creates three debug files:
migration_attr: used to obtain the attribute parameters of the
current live migration device.
migration_data: used to get the live migration data of the current
live migration device.
migration_debug: Used to debug the current live migration device
through commands.

The live migration function of the current device can be tested by
operating the debug files, and the functional status of the equipment
and software at each stage can be tested step by step without
performing the complete live migration function. And after the live
migration is performed, the migration device data of the live migration
can be obtained through the debug files.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 drivers/vfio/Makefile       |  2 +-
 drivers/vfio/vfio.h         | 14 +++++++
 drivers/vfio/vfio_debugfs.c | 82 +++++++++++++++++++++++++++++++++++++
 drivers/vfio/vfio_main.c    |  5 +++
 include/linux/vfio.h        |  8 ++++
 5 files changed, 110 insertions(+), 1 deletion(-)
 create mode 100644 drivers/vfio/vfio_debugfs.c

diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile
index 70e7dcb302ef..1debcff31d30 100644
--- a/drivers/vfio/Makefile
+++ b/drivers/vfio/Makefile
@@ -7,7 +7,7 @@ vfio-y += vfio_main.o \
 vfio-$(CONFIG_IOMMUFD) += iommufd.o
 vfio-$(CONFIG_VFIO_CONTAINER) += container.o
 vfio-$(CONFIG_VFIO_VIRQFD) += virqfd.o
-
+vfio-$(CONFIG_DEBUG_FS) += vfio_debugfs.o
 obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o
 obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o
 obj-$(CONFIG_VFIO_PCI) += pci/
diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h
index e9721d8424bc..66c00f97e9cc 100644
--- a/drivers/vfio/vfio.h
+++ b/drivers/vfio/vfio.h
@@ -258,4 +258,18 @@ static inline void vfio_device_put_kvm(struct vfio_device *device)
 }
 #endif
 
+#ifdef CONFIG_DEBUG_FS
+void vfio_debugfs_create_root(void);
+void vfio_debugfs_remove_root(void);
+
+void vfio_vf_debugfs_init(struct vfio_device *vdev);
+void vfio_vf_debugfs_exit(struct vfio_device *vdev);
+#else
+static inline void vfio_debugfs_create_root(void) { }
+static inline void vfio_debugfs_remove_root(void) { }
+
+static inline void vfio_vf_debugfs_init(struct vfio_device *vdev) { }
+static inline void vfio_vf_debugfs_exit(struct vfio_device *vdev) { }
+#endif /* CONFIG_DEBUG_FS */
+
 #endif
diff --git a/drivers/vfio/vfio_debugfs.c b/drivers/vfio/vfio_debugfs.c
new file mode 100644
index 000000000000..c5df1496fe0e
--- /dev/null
+++ b/drivers/vfio/vfio_debugfs.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023, HiSilicon Ltd.
+ */
+
+#include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/vfio.h>
+#include "vfio.h"
+
+static struct dentry *vfio_debugfs_root;
+
+static int vfio_vf_state_read(struct seq_file *seq, void *data)
+{
+	struct device *vf_dev = seq->private;
+	struct vfio_device *vdev = container_of(vf_dev, struct vfio_device, device);
+	enum vfio_device_mig_state state;
+	int ret;
+
+	ret = vdev->mig_ops->migration_get_state(vdev, &state);
+	if (ret) {
+		dev_err(vf_dev, "failed to get device migration state");
+		return -EINVAL;
+	}
+
+	switch (state) {
+	case VFIO_DEVICE_STATE_RUNNING:
+		seq_printf(seq, "%s\n", "RUNNING");
+		break;
+	case VFIO_DEVICE_STATE_STOP_COPY:
+		seq_printf(seq, "%s\n", "STOP_COPY");
+		break;
+	case VFIO_DEVICE_STATE_STOP:
+		seq_printf(seq, "%s\n", "STOP");
+		break;
+	case VFIO_DEVICE_STATE_RESUMING:
+		seq_printf(seq, "%s\n", "RESUMING");
+		break;
+	case VFIO_DEVICE_STATE_RUNNING_P2P:
+		seq_printf(seq, "%s\n", "RESUMING_P2P");
+		break;
+	case VFIO_DEVICE_STATE_ERROR:
+		seq_printf(seq, "%s\n", "ERROR");
+		break;
+	default:
+		seq_printf(seq, "%s\n", "Invalid");
+	}
+
+	return 0;
+}
+
+void vfio_vf_debugfs_init(struct vfio_device *vdev)
+{
+	struct device *dev = &vdev->device;
+
+	vdev->debug_root = debugfs_create_dir(dev_name(vdev->dev), vfio_debugfs_root);
+
+	debugfs_create_devm_seqfile(dev, "migration_state", vdev->debug_root,
+				  vfio_vf_state_read);
+}
+EXPORT_SYMBOL_GPL(vfio_vf_debugfs_init);
+
+void vfio_vf_debugfs_exit(struct vfio_device *vdev)
+{
+	debugfs_remove_recursive(vdev->debug_root);
+}
+EXPORT_SYMBOL_GPL(vfio_vf_debugfs_exit);
+
+void  vfio_debugfs_create_root(void)
+{
+	vfio_debugfs_root = debugfs_create_dir("vfio", NULL);
+}
+EXPORT_SYMBOL_GPL(vfio_debugfs_create_root);
+
+void  vfio_debugfs_remove_root(void)
+{
+	debugfs_remove_recursive(vfio_debugfs_root);
+	vfio_debugfs_root = NULL;
+}
+EXPORT_SYMBOL_GPL(vfio_debugfs_remove_root);
+
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 3a597e799918..09772fd3a396 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -1408,6 +1408,9 @@ static int __init vfio_init(void)
 	}
 
 	pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
+
+	vfio_debugfs_create_root();
+
 	return 0;
 
 err_dev_class:
@@ -1425,6 +1428,8 @@ static void __exit vfio_cleanup(void)
 	vfio_virqfd_exit();
 	vfio_group_cleanup();
 	xa_destroy(&vfio_device_set_xa);
+
+	vfio_debugfs_remove_root();
 }
 
 module_init(vfio_init);
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 93134b023968..fa6b898ebb58 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -63,6 +63,14 @@ struct vfio_device {
 	struct iommufd_ctx *iommufd_ictx;
 	bool iommufd_attached;
 #endif
+
+#ifdef CONFIG_DEBUG_FS
+	/*
+	 * debug_root is a static property of the vfio_device
+	 * which must be set prior to registering the vfio_device.
+	 */
+	struct dentry *debug_root;
+#endif
 };
 
 /**
-- 
2.24.0

[PATCH v8 2/5] hisi_acc_vfio_pci: extract public functions for container_of

[Longfang Liu]

In the current driver, vdev is obtained from struct
hisi_acc_vf_core_device through the container_of function.
This method is used in many places in the driver. In order to
reduce this repetitive operation, I extracted a public function
to replace it.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 21 ++++++++++---------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index a117eaf21c14..a1589947e721 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
@@ -630,6 +630,12 @@ static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vde
 	}
 }
 
+static struct hisi_acc_vf_core_device *hisi_acc_get_vf_dev(struct vfio_device *vdev)
+{
+	return container_of(vdev, struct hisi_acc_vf_core_device,
+			    core_device.vdev);
+}
+
 /*
  * This function is called in all state_mutex unlock cases to
  * handle a 'deferred_reset' if exists.
@@ -1042,8 +1048,7 @@ static struct file *
 hisi_acc_vfio_pci_set_device_state(struct vfio_device *vdev,
 				   enum vfio_device_mig_state new_state)
 {
-	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(vdev,
-			struct hisi_acc_vf_core_device, core_device.vdev);
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
 	enum vfio_device_mig_state next_state;
 	struct file *res = NULL;
 	int ret;
@@ -1084,8 +1089,7 @@ static int
 hisi_acc_vfio_pci_get_device_state(struct vfio_device *vdev,
 				   enum vfio_device_mig_state *curr_state)
 {
-	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(vdev,
-			struct hisi_acc_vf_core_device, core_device.vdev);
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
 
 	mutex_lock(&hisi_acc_vdev->state_mutex);
 	*curr_state = hisi_acc_vdev->mig_state;
@@ -1301,8 +1305,7 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
 
 static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
 {
-	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev,
-			struct hisi_acc_vf_core_device, core_device.vdev);
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
 	struct vfio_pci_core_device *vdev = &hisi_acc_vdev->core_device;
 	int ret;
 
@@ -1325,8 +1328,7 @@ static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
 
 static void hisi_acc_vfio_pci_close_device(struct vfio_device *core_vdev)
 {
-	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev,
-			struct hisi_acc_vf_core_device, core_device.vdev);
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
 	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
 
 	iounmap(vf_qm->io_base);
@@ -1341,8 +1343,7 @@ static const struct vfio_migration_ops hisi_acc_vfio_pci_migrn_state_ops = {
 
 static int hisi_acc_vfio_pci_migrn_init_dev(struct vfio_device *core_vdev)
 {
-	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev,
-			struct hisi_acc_vf_core_device, core_device.vdev);
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
 	struct pci_dev *pdev = to_pci_dev(core_vdev->dev);
 	struct hisi_qm *pf_qm = hisi_acc_get_pf_qm(pdev);
 
-- 
2.24.0

[PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

[Longfang Liu]

On the debugfs framework of VFIO, if the CONFIG_DEBUG_FS macro is
enabled, the debug function is registered for the live migration driver
of the HiSilicon accelerator device.

On the basis of the original public debug function, a private debug
function is added:

mig_data file: used to get the migration data of the live migration device
mig_attr file: used to get device attributes of the live migration device
debug file: used to test for acquiring and writing device state data
for VF device.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 282 ++++++++++++++++++
 .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h    |  11 +
 2 files changed, 293 insertions(+)

diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index a1589947e721..a0ecb1cd5707 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
@@ -15,6 +15,7 @@
 #include <linux/anon_inodes.h>
 
 #include "hisi_acc_vfio_pci.h"
+#include "../../vfio.h"
 
 /* Return 0 on VM acc device ready, -ETIMEDOUT hardware timeout */
 static int qm_wait_dev_not_ready(struct hisi_qm *qm)
@@ -606,6 +607,18 @@ hisi_acc_check_int_state(struct hisi_acc_vf_core_device *hisi_acc_vdev)
 	}
 }
 
+static void hisi_acc_vf_migf_save(struct hisi_acc_vf_migration_file *src_migf,
+	struct hisi_acc_vf_migration_file *dst_migf)
+{
+	if (!dst_migf)
+		return;
+
+	dst_migf->disabled = false;
+	dst_migf->total_length = src_migf->total_length;
+	memcpy(&dst_migf->vf_data, &src_migf->vf_data,
+		    sizeof(struct acc_vf_data));
+}
+
 static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
 {
 	mutex_lock(&migf->lock);
@@ -618,12 +631,16 @@ static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
 static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vdev)
 {
 	if (hisi_acc_vdev->resuming_migf) {
+		hisi_acc_vf_migf_save(hisi_acc_vdev->resuming_migf,
+						hisi_acc_vdev->debug_migf);
 		hisi_acc_vf_disable_fd(hisi_acc_vdev->resuming_migf);
 		fput(hisi_acc_vdev->resuming_migf->filp);
 		hisi_acc_vdev->resuming_migf = NULL;
 	}
 
 	if (hisi_acc_vdev->saving_migf) {
+		hisi_acc_vf_migf_save(hisi_acc_vdev->saving_migf,
+						hisi_acc_vdev->debug_migf);
 		hisi_acc_vf_disable_fd(hisi_acc_vdev->saving_migf);
 		fput(hisi_acc_vdev->saving_migf->filp);
 		hisi_acc_vdev->saving_migf = NULL;
@@ -1303,6 +1320,265 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
 	return vfio_pci_core_ioctl(core_vdev, cmd, arg);
 }
 
+static int hisi_acc_vf_debug_io(struct vfio_device *vdev)
+{
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
+	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
+	struct device *dev = vdev->dev;
+	u64 data;
+	int ret;
+
+	ret = qm_wait_dev_not_ready(vf_qm);
+	if (ret)
+		dev_err(dev, "VF device not ready!\n");
+
+	data = readl(vf_qm->io_base + QM_MB_CMD_SEND_BASE);
+	dev_info(dev, "debug mailbox val: 0x%llx\n", data);
+
+	return ret;
+}
+
+static int hisi_acc_vf_debug_resume(struct vfio_device *vdev)
+{
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
+	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
+	struct device *dev = vdev->dev;
+	int ret;
+
+	ret = vf_qm_state_save(hisi_acc_vdev, migf);
+	if (ret) {
+		dev_err(dev, "failed to save device data!\n");
+		return -EINVAL;
+	}
+
+	ret = vf_qm_check_match(hisi_acc_vdev, migf);
+	if (ret) {
+		dev_err(dev, "failed to match the VF!\n");
+		return -EINVAL;
+	}
+
+	ret = vf_qm_load_data(hisi_acc_vdev, migf);
+	if (ret) {
+		dev_err(dev, "failed to recover the VF!\n");
+		return -EINVAL;
+	}
+
+	vf_qm_fun_reset(&hisi_acc_vdev->vf_qm);
+	dev_info(dev, "successful to resume device data!\n");
+
+	return 0;
+}
+
+static int hisi_acc_vf_debug_save(struct vfio_device *vdev)
+{
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
+	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
+	struct device *dev = vdev->dev;
+	int ret;
+
+	ret = vf_qm_state_save(hisi_acc_vdev, migf);
+	if (ret) {
+		dev_err(dev, "failed to save device data!\n");
+		return -EINVAL;
+	}
+	dev_info(dev, "successful to save device data!\n");
+
+	return 0;
+}
+
+static int
+hisi_acc_vf_debug_operate(struct vfio_device *vdev, unsigned int cmd)
+{
+	int ret;
+
+	switch (cmd) {
+	case STATE_SAVE:
+		ret = hisi_acc_vf_debug_save(vdev);
+		if (ret)
+			return ret;
+		break;
+	case STATE_RESUME:
+		ret = hisi_acc_vf_debug_resume(vdev);
+		if (ret)
+			return ret;
+		break;
+	case RW_IO_TEST:
+		ret = hisi_acc_vf_debug_io(vdev);
+		if (ret)
+			return ret;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int hisi_acc_vf_debug_check(struct vfio_device *vdev)
+{
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
+	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
+	enum vfio_device_mig_state state;
+
+	if (!vdev->mig_ops || !migf) {
+		dev_err(vdev->dev, "device not support debugfs!\n");
+		return -EINVAL;
+	}
+
+	/* If device not opened, the debugfs operation will trigger calltrace */
+	(void)vdev->mig_ops->migration_get_state(vdev, &state);
+	if (state == VFIO_DEVICE_STATE_ERROR ||
+	    state == VFIO_DEVICE_STATE_STOP) {
+		dev_err(vdev->dev, "device not opened!\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static ssize_t hisi_acc_vf_debug_write(struct file *filp, const char __user *buffer,
+			    size_t count, loff_t *pos)
+{
+	struct vfio_device	*vdev = filp->private_data;
+	char tbuf[VFIO_DEV_DBG_LEN];
+	unsigned long cmd;
+	int len, ret;
+
+	if (*pos)
+		return 0;
+
+	if (count >= VFIO_DEV_DBG_LEN)
+		return -ENOSPC;
+
+	ret = hisi_acc_vf_debug_check(vdev);
+	if (ret)
+		return -EINVAL;
+
+	len = simple_write_to_buffer(tbuf, VFIO_DEV_DBG_LEN - 1,
+					pos, buffer, count);
+	if (len < 0 || len > VFIO_DEV_DBG_LEN - 1)
+		return -EINVAL;
+	tbuf[len] = '\0';
+	if (kstrtoul(tbuf, 0, &cmd))
+		return -EFAULT;
+
+	ret = hisi_acc_vf_debug_operate(vdev, cmd);
+	if (ret) {
+		dev_err(vdev->dev, "device debug test failed!\n");
+		return -EINVAL;
+	}
+
+	return count;
+}
+
+static const struct file_operations hisi_acc_vf_debug_fops = {
+	.owner = THIS_MODULE,
+	.open = simple_open,
+	.write = hisi_acc_vf_debug_write,
+};
+
+static void seq_print_hex_data(struct seq_file *seq, const void *buf, size_t len)
+{
+#define HEX_LINE_SIZE		131
+#define HEX_ROW_SIZE		16
+	unsigned char linebuf[HEX_LINE_SIZE];
+	int i, linelen, remaining = len;
+	const u8 *ptr = buf;
+
+	for (i = 0; i < len; i += HEX_ROW_SIZE) {
+		linelen = min(remaining, HEX_ROW_SIZE);
+		remaining -= HEX_ROW_SIZE;
+
+		hex_dump_to_buffer(ptr + i, linelen, HEX_ROW_SIZE, 1,
+					linebuf, sizeof(linebuf), false);
+
+		seq_printf(seq, "%s%.8x: %s\n", "Mig Data:", i, linebuf);
+	}
+}
+
+static int hisi_acc_vf_data_read(struct seq_file *seq, void *data)
+{
+	struct device *vf_dev = seq->private;
+	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
+	struct vfio_device	*vdev = &core_device->vdev;
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
+	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
+	size_t vf_data_sz = offsetofend(struct acc_vf_data, padding);
+
+	if (debug_migf && debug_migf->total_length)
+		seq_print_hex_data(seq, (unsigned char *)&debug_migf->vf_data,
+				vf_data_sz);
+	else
+		seq_printf(seq, "%s\n", "device not migrated!");
+
+	return 0;
+}
+
+static int hisi_acc_vf_attr_read(struct seq_file *seq, void *data)
+{
+	struct device *vf_dev = seq->private;
+	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
+	struct vfio_device	*vdev = &core_device->vdev;
+	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
+	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
+
+	if (debug_migf && debug_migf->total_length) {
+		seq_printf(seq,
+			 "acc device:\n"
+			 "device  state: %d\n"
+			 "device  ready: %u\n"
+			 "data    valid: %d\n"
+			 "data     size: %lu\n",
+			 hisi_acc_vdev->mig_state,
+			 hisi_acc_vdev->vf_qm_state,
+			 debug_migf->disabled,
+			 debug_migf->total_length);
+	} else {
+		seq_printf(seq, "%s\n", "device not migrated!");
+	}
+
+	return 0;
+}
+
+static int hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vdev)
+{
+	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
+	struct device *dev = vdev->dev;
+	void *migf = NULL;
+
+	if (!debugfs_initialized())
+		return 0;
+
+	vfio_vf_debugfs_init(vdev);
+
+	migf = kzalloc(sizeof(struct hisi_acc_vf_migration_file), GFP_KERNEL);
+	if (!migf)
+		return -ENOMEM;
+
+	hisi_acc_vdev->debug_migf = migf;
+
+	debugfs_create_devm_seqfile(dev, "migration_data", vdev->debug_root,
+				  hisi_acc_vf_data_read);
+	debugfs_create_devm_seqfile(dev, "migration_attr", vdev->debug_root,
+				  hisi_acc_vf_attr_read);
+
+	debugfs_create_file("migration_debug", 0200, vdev->debug_root,
+				  vdev, &hisi_acc_vf_debug_fops);
+
+	return 0;
+}
+
+static void hisi_acc_vf_debugfs_exit(struct hisi_acc_vf_core_device *hisi_acc_vdev)
+{
+	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
+
+	if (!debugfs_initialized())
+		return;
+
+	vfio_vf_debugfs_exit(vdev);
+	kfree(hisi_acc_vdev->debug_migf);
+}
+
 static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
 {
 	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
@@ -1416,6 +1692,9 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
 	if (IS_ERR(hisi_acc_vdev))
 		return PTR_ERR(hisi_acc_vdev);
 
+	if (ops == &hisi_acc_vfio_pci_migrn_ops)
+		hisi_acc_vfio_debug_init(hisi_acc_vdev);
+
 	dev_set_drvdata(&pdev->dev, &hisi_acc_vdev->core_device);
 	ret = vfio_pci_core_register_device(&hisi_acc_vdev->core_device);
 	if (ret)
@@ -1423,6 +1702,8 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
 	return 0;
 
 out_put_vdev:
+	if (ops == &hisi_acc_vfio_pci_migrn_ops)
+		hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
 	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
 	return ret;
 }
@@ -1431,6 +1712,7 @@ static void hisi_acc_vfio_pci_remove(struct pci_dev *pdev)
 {
 	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_drvdata(pdev);
 
+	hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
 	vfio_pci_core_unregister_device(&hisi_acc_vdev->core_device);
 	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
 }
diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
index dcabfeec6ca1..ef50b12f018d 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
@@ -49,6 +49,14 @@
 #define QM_EQC_DW0		0X8000
 #define QM_AEQC_DW0		0X8020
 
+#define VFIO_DEV_DBG_LEN		256
+
+enum mig_debug_cmd {
+	STATE_SAVE,
+	STATE_RESUME,
+	RW_IO_TEST,
+};
+
 struct acc_vf_data {
 #define QM_MATCH_SIZE offsetofend(struct acc_vf_data, qm_rsv_state)
 	/* QM match information */
@@ -113,5 +121,8 @@ struct hisi_acc_vf_core_device {
 	spinlock_t reset_lock;
 	struct hisi_acc_vf_migration_file *resuming_migf;
 	struct hisi_acc_vf_migration_file *saving_migf;
+
+	/* For debugfs */
+	struct hisi_acc_vf_migration_file *debug_migf;
 };
 #endif /* HISI_ACC_VFIO_PCI_H */
-- 
2.24.0

[PATCH v8 4/5] Documentation: add debugfs description for vfio

[Longfang Liu]

Add two debugfs document description file to help users understand
how to use the accelerator live migration driver's debugfs.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 .../ABI/testing/debugfs-hisi-migration        | 28 +++++++++++++++++++
 Documentation/ABI/testing/debugfs-vfio        | 17 +++++++++++
 2 files changed, 45 insertions(+)
 create mode 100644 Documentation/ABI/testing/debugfs-hisi-migration
 create mode 100644 Documentation/ABI/testing/debugfs-vfio

diff --git a/Documentation/ABI/testing/debugfs-hisi-migration b/Documentation/ABI/testing/debugfs-hisi-migration
new file mode 100644
index 000000000000..0f45f30ff6d4
--- /dev/null
+++ b/Documentation/ABI/testing/debugfs-hisi-migration
@@ -0,0 +1,28 @@
+What:		/sys/kernel/debug/vfio/<bdf>/migration_data
+Date:		Feb 2023
+KernelVersion:  6.2
+Contact:	linux-kernel@vger.kernel.org
+Description:	Read the live migration data of the vfio device.
+		The output format of the data is defined by the live
+		migration driver.
+
+What:		/sys/kernel/debug/vfio/<bdf>/migration_attr
+Date:		Feb 2023
+KernelVersion:  6.2
+Contact:	linux-kernel@vger.kernel.org
+Description:	Read the live migration attributes of the vfio device.
+		The output format of the attributes is defined by the live
+		migration driver.
+
+What:		/sys/kernel/debug/vfio/<bdf>/migration_debug
+Date:		Feb 2023
+KernelVersion:  6.2
+Contact:	linux-kernel@vger.kernel.org
+Description:	This debug file supports "echo" command	write operations.
+		The command is actually represented by an integer number, and the
+		specific meaning is defined by the corresponding device driver.
+		For example, three commands are defined in the HiSilicon accelerator
+		live migration driver:
+		0: State save
+		1: State resume
+		2: IO test
diff --git a/Documentation/ABI/testing/debugfs-vfio b/Documentation/ABI/testing/debugfs-vfio
new file mode 100644
index 000000000000..e22531d16674
--- /dev/null
+++ b/Documentation/ABI/testing/debugfs-vfio
@@ -0,0 +1,17 @@
+What:		/sys/kernel/debug/vfio
+Date:		Feb 2023
+KernelVersion:  6.2
+Contact:	linux-kernel@vger.kernel.org
+Description:	This debugfs file directory is used for debugging
+		of vfio devices that support live migration.
+		Each device that supports live migration can create a device
+		subdirectory under this directory by referencing the public
+		registration interface.
+
+What:		/sys/kernel/debug/vfio/<bdf>/migration_state
+Date:		Feb 2023
+KernelVersion:  6.2
+Contact:	linux-kernel@vger.kernel.org
+Description:	Read the live migration status of the vfio device.
+		The status of these live migrations includes:
+		ERROR, RUNNING, STOP, STOP_COPY, RESUMING.
-- 
2.24.0

[PATCH v8 5/5] vfio: update live migration device status

[Longfang Liu]

migration debugfs needs to perform debug operations based on the
status of the current device. If the device is not loaded or has
stopped, debugfs does not allow operations.

so, after the live migration function is executed and the device is
turned off, the device no longer needs to be accessed. At this time,
the status of the device needs to be set to stop.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 3 +++
 drivers/vfio/pci/mlx5/main.c                   | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index a0ecb1cd5707..ec73e8b19c89 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
@@ -1607,6 +1607,9 @@ static void hisi_acc_vfio_pci_close_device(struct vfio_device *core_vdev)
 	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
 	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
 
+	if (core_vdev->mig_ops)
+		hisi_acc_vdev->mig_state = VFIO_DEVICE_STATE_STOP;
+
 	iounmap(vf_qm->io_base);
 	vfio_pci_core_close_device(core_vdev);
 }
diff --git a/drivers/vfio/pci/mlx5/main.c b/drivers/vfio/pci/mlx5/main.c
index e897537a9e8a..dc3564436946 100644
--- a/drivers/vfio/pci/mlx5/main.c
+++ b/drivers/vfio/pci/mlx5/main.c
@@ -1269,6 +1269,9 @@ static void mlx5vf_pci_close_device(struct vfio_device *core_vdev)
 	struct mlx5vf_pci_core_device *mvdev = container_of(
 		core_vdev, struct mlx5vf_pci_core_device, core_device.vdev);
 
+	if (mvdev->migrate_cap)
+		mvdev->mig_state = VFIO_DEVICE_STATE_STOP;
+
 	mlx5vf_cmd_close_migratable(mvdev);
 	vfio_pci_core_close_device(core_vdev);
 }
-- 
2.24.0

Re: [PATCH v8 0/5] add debugfs to migration driver

[liulongfang]

On 2023/2/17 16:48, Longfang Liu wrote:
> Add a debugfs function to the migration driver in VFIO to provide
> a step-by-step test function for the migration driver.
> 
> When the execution of live migration fails, the user can view the
> status and data during the migration process separately from the
> source and the destination, which is convenient for users to analyze
> and locate problems.
> 
> Changes v7 -> v8
> 	Add support for platform devices.
> 
> Changes v6 -> v7
> 	Fix some code style issues.
> 
> Changes v5 -> v6
> 	Control the creation of debugfs through the CONFIG_DEBUG_FS.
> 
> Changes v4 -> v5
> 	Remove the newly added vfio_migration_ops and use seq_printf
> 	to optimize the implementation of debugfs.
> 
> Changes v3 -> v4
> 	Change the migration_debug_operate interface to debug_root file.
> 
> Changes v2 -> v3
> 	Extend the debugfs function from hisilicon device to vfio.
> 
> Changes v1 -> v2
> 	Change the registration method of root_debugfs to register
> 	with module initialization.
> 
> Longfang Liu (5):
>   vfio/migration: Add debugfs to live migration driver
>   hisi_acc_vfio_pci: extract public functions for container_of
>   hisi_acc_vfio_pci: register debugfs for hisilicon migration driver
>   Documentation: add debugfs description for vfio
>   vfio: update live migration device status
> 
>  .../ABI/testing/debugfs-hisi-migration        |  28 ++
>  Documentation/ABI/testing/debugfs-vfio        |  17 +
>  drivers/vfio/Makefile                         |   2 +-
>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 306 +++++++++++++++++-
>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h    |  11 +
>  drivers/vfio/pci/mlx5/main.c                  |   3 +
>  drivers/vfio/vfio.h                           |  14 +
>  drivers/vfio/vfio_debugfs.c                   |  82 +++++
>  drivers/vfio/vfio_main.c                      |   5 +
>  include/linux/vfio.h                          |   8 +
>  10 files changed, 465 insertions(+), 11 deletions(-)
>  create mode 100644 Documentation/ABI/testing/debugfs-hisi-migration
>  create mode 100644 Documentation/ABI/testing/debugfs-vfio
>  create mode 100644 drivers/vfio/vfio_debugfs.c
> 
Hi Alex:
please help to review this patchset.
thanks.

Longfang.

Re: [PATCH v8 1/5] vfio/migration: Add debugfs to live migration driver

[Jason Gunthorpe]

On Fri, Feb 17, 2023 at 04:48:27PM +0800, Longfang Liu wrote:
> +void vfio_vf_debugfs_init(struct vfio_device *vdev)
> +{
> +	struct device *dev = &vdev->device;
> +
> +	vdev->debug_root = debugfs_create_dir(dev_name(vdev->dev), vfio_debugfs_root);
> +
> +	debugfs_create_devm_seqfile(dev, "migration_state", vdev->debug_root,
> +				  vfio_vf_state_read);
> +}
> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_init);
> +
> +void vfio_vf_debugfs_exit(struct vfio_device *vdev)
> +{
> +	debugfs_remove_recursive(vdev->debug_root);
> +}
> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_exit);
> +
> +void  vfio_debugfs_create_root(void)
> +{
> +	vfio_debugfs_root = debugfs_create_dir("vfio", NULL);
> +}
> +EXPORT_SYMBOL_GPL(vfio_debugfs_create_root);
> +
> +void  vfio_debugfs_remove_root(void)
> +{
> +	debugfs_remove_recursive(vfio_debugfs_root);
> +	vfio_debugfs_root = NULL;
> +}
> +EXPORT_SYMBOL_GPL(vfio_debugfs_remove_root);

Why are these symbols exported?

Jason

Re: [PATCH v8 2/5] hisi_acc_vfio_pci: extract public functions for container_of

[Jason Gunthorpe]

On Fri, Feb 17, 2023 at 04:48:28PM +0800, Longfang Liu wrote:
> In the current driver, vdev is obtained from struct
> hisi_acc_vf_core_device through the container_of function.
> This method is used in many places in the driver. In order to
> reduce this repetitive operation, I extracted a public function
> to replace it.
> 
> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
> ---
>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 21 ++++++++++---------
>  1 file changed, 11 insertions(+), 10 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Jason

Re: [PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

[Jason Gunthorpe]

On Fri, Feb 17, 2023 at 04:48:29PM +0800, Longfang Liu wrote:

> +static int hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vdev)
> +{
> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
> +	struct device *dev = vdev->dev;
> +	void *migf = NULL;
> +
> +	if (!debugfs_initialized())
> +		return 0;
> +
> +	vfio_vf_debugfs_init(vdev);

This is weirdly named with _vf_, this is just
vfio_device_debufs_init()

Jason

Re: [PATCH v8 4/5] Documentation: add debugfs description for vfio

[Alex Williamson]

On Fri, 17 Feb 2023 16:48:30 +0800
Longfang Liu <liulongfang@huawei.com> wrote:

> Add two debugfs document description file to help users understand
> how to use the accelerator live migration driver's debugfs.
> 
> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
> ---
>  .../ABI/testing/debugfs-hisi-migration        | 28 +++++++++++++++++++
>  Documentation/ABI/testing/debugfs-vfio        | 17 +++++++++++
>  2 files changed, 45 insertions(+)
>  create mode 100644 Documentation/ABI/testing/debugfs-hisi-migration
>  create mode 100644 Documentation/ABI/testing/debugfs-vfio
> 
> diff --git a/Documentation/ABI/testing/debugfs-hisi-migration b/Documentation/ABI/testing/debugfs-hisi-migration
> new file mode 100644
> index 000000000000..0f45f30ff6d4
> --- /dev/null
> +++ b/Documentation/ABI/testing/debugfs-hisi-migration
> @@ -0,0 +1,28 @@
> +What:		/sys/kernel/debug/vfio/<bdf>/migration_data

s/bdf/name/ throughout.

> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@vger.kernel.org

Is there not someone at Huawei willing to be the contact point for the
hisi_acc specific attributes?

> +Description:	Read the live migration data of the vfio device.
> +		The output format of the data is defined by the live
> +		migration driver.
> +
> +What:		/sys/kernel/debug/vfio/<bdf>/migration_attr
> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@vger.kernel.org
> +Description:	Read the live migration attributes of the vfio device.
> +		The output format of the attributes is defined by the live
> +		migration driver.
> +
> +What:		/sys/kernel/debug/vfio/<bdf>/migration_debug
> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@vger.kernel.org
> +Description:	This debug file supports "echo" command	write operations.
> +		The command is actually represented by an integer number, and the
> +		specific meaning is defined by the corresponding device driver.
> +		For example, three commands are defined in the HiSilicon accelerator
> +		live migration driver:
> +		0: State save
> +		1: State resume
> +		2: IO test
> diff --git a/Documentation/ABI/testing/debugfs-vfio b/Documentation/ABI/testing/debugfs-vfio
> new file mode 100644
> index 000000000000..e22531d16674
> --- /dev/null
> +++ b/Documentation/ABI/testing/debugfs-vfio
> @@ -0,0 +1,17 @@
> +What:		/sys/kernel/debug/vfio
> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@vger.kernel.org

These should likely at least be the kvm list as the official list of
vfio if you're not interested in being the contact point.

Thanks,
Alex

> +Description:	This debugfs file directory is used for debugging
> +		of vfio devices that support live migration.
> +		Each device that supports live migration can create a device
> +		subdirectory under this directory by referencing the public
> +		registration interface.
> +
> +What:		/sys/kernel/debug/vfio/<bdf>/migration_state
> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@vger.kernel.org
> +Description:	Read the live migration status of the vfio device.
> +		The status of these live migrations includes:
> +		ERROR, RUNNING, STOP, STOP_COPY, RESUMING.

Re: [PATCH v8 1/5] vfio/migration: Add debugfs to live migration driver

[Alex Williamson]

On Fri, 17 Feb 2023 16:48:27 +0800
Longfang Liu <liulongfang@huawei.com> wrote:

> There are multiple devices, software and operational steps involved
> in the process of live migration. An error occurred on any node may
> cause the live migration operation to fail.
> This complex process makes it very difficult to locate and analyze
> the cause when the function fails.
> 
> In order to quickly locate the cause of the problem when the
> live migration fails, I added a set of debugfs to the vfio
> live migration driver.
>                                +-------------------------------------------+
>                                |                                           |
>                                |                                           |
>                                |                  QEMU                     |
>                                |                                           |
>                                |                                           |
>                                +---+----------------------------+----------+
>                                    |      ^                     |      ^
>                                    |      |                     |      |
>  +--------+                        |      |                     |      |
>  |  vfio  |                        v      |                     v      |
>  +--------+                     +---------+--+               +---------+--+
>      ^                          |src vfio_dev|               |dst vfio_dev|
>      |                          +--+---------+               +--+---------+
>      |                             |      ^                     |      ^
>      |                             |      |                     |      |
>      |                             v      |                     |      |
>      |  +-----------+         +-----------+----+                |      |
>      +--+<bdf>file_x+<----+---+migration_attr  |                |      |
>      |  +-----------+     |   +----------------+                |      |
>      |                    +---+migration_data  |                |      |
>      |                    |   +----------------+                |      |
>      |                    +---+migration_debug |                |      |
>      |                    |   +----------------+                |      |
>      |                    |   +----------------+                |      |
>      |                    +---+migration_state |                |      |
>      |                        +----------------+                |      |
>      |                                                          |      |
>      |  +-----------+         +----------------+                |      |
>      +--+<bdf>file_y|<----+---+migration_attr  |                |      |
>         +-----------+     |   +----------------+                |      |
>                           +---+migration_data  |                |      |
>                           |   +----------------+<---------------+      |
>                           +---+migration_debug |                       |
>                           |   +----------------+                       |
>                           |   +----------------+                       |
>                           +---+migration_state +-----------------------+
>                               +----------------+
> 
> The entire debugfs directory will be based on the definition of
> the CONFIG_DEBUG_FS macro. If this macro is not enabled, the
> interfaces in vfio.h will be empty definitions, and the creation
> and initialization of the debugfs directory will not be executed.
> 
> debugfs will create a public root directory "vfio" file.
> then create a device <bdf> named file for each live migration device.

dev_name(), it's only <sbdf> for PCI devices.

> First, create a unified state acquisition file of "migration_state"
> in this device directory.
> Then, create your own debugging files independently according to
> the functional requirements of each device.
> 
> Here, HiSilicon accelerator creates three debug files:
> migration_attr: used to obtain the attribute parameters of the
> current live migration device.
> migration_data: used to get the live migration data of the current
> live migration device.
> migration_debug: Used to debug the current live migration device
> through commands.
> 
> The live migration function of the current device can be tested by
> operating the debug files, and the functional status of the equipment
> and software at each stage can be tested step by step without
> performing the complete live migration function. And after the live
> migration is performed, the migration device data of the live migration
> can be obtained through the debug files.
> 
> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
> ---
>  drivers/vfio/Makefile       |  2 +-
>  drivers/vfio/vfio.h         | 14 +++++++
>  drivers/vfio/vfio_debugfs.c | 82 +++++++++++++++++++++++++++++++++++++
>  drivers/vfio/vfio_main.c    |  5 +++
>  include/linux/vfio.h        |  8 ++++
>  5 files changed, 110 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/vfio/vfio_debugfs.c
> 
> diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile
> index 70e7dcb302ef..1debcff31d30 100644
> --- a/drivers/vfio/Makefile
> +++ b/drivers/vfio/Makefile
> @@ -7,7 +7,7 @@ vfio-y += vfio_main.o \
>  vfio-$(CONFIG_IOMMUFD) += iommufd.o
>  vfio-$(CONFIG_VFIO_CONTAINER) += container.o
>  vfio-$(CONFIG_VFIO_VIRQFD) += virqfd.o
> -
> +vfio-$(CONFIG_DEBUG_FS) += vfio_debugfs.o
>  obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o
>  obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o
>  obj-$(CONFIG_VFIO_PCI) += pci/
> diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h
> index e9721d8424bc..66c00f97e9cc 100644
> --- a/drivers/vfio/vfio.h
> +++ b/drivers/vfio/vfio.h
> @@ -258,4 +258,18 @@ static inline void vfio_device_put_kvm(struct vfio_device *device)
>  }
>  #endif
>  
> +#ifdef CONFIG_DEBUG_FS
> +void vfio_debugfs_create_root(void);
> +void vfio_debugfs_remove_root(void);
> +
> +void vfio_vf_debugfs_init(struct vfio_device *vdev);
> +void vfio_vf_debugfs_exit(struct vfio_device *vdev);

s/vf_// throughout.

> +#else
> +static inline void vfio_debugfs_create_root(void) { }
> +static inline void vfio_debugfs_remove_root(void) { }
> +
> +static inline void vfio_vf_debugfs_init(struct vfio_device *vdev) { }
> +static inline void vfio_vf_debugfs_exit(struct vfio_device *vdev) { }
> +#endif /* CONFIG_DEBUG_FS */
> +
>  #endif
> diff --git a/drivers/vfio/vfio_debugfs.c b/drivers/vfio/vfio_debugfs.c
> new file mode 100644
> index 000000000000..c5df1496fe0e
> --- /dev/null
> +++ b/drivers/vfio/vfio_debugfs.c
> @@ -0,0 +1,82 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2023, HiSilicon Ltd.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/debugfs.h>
> +#include <linux/seq_file.h>
> +#include <linux/vfio.h>
> +#include "vfio.h"
> +
> +static struct dentry *vfio_debugfs_root;
> +
> +static int vfio_vf_state_read(struct seq_file *seq, void *data)
> +{
> +	struct device *vf_dev = seq->private;
> +	struct vfio_device *vdev = container_of(vf_dev, struct vfio_device, device);
> +	enum vfio_device_mig_state state;
> +	int ret;
> +
> +	ret = vdev->mig_ops->migration_get_state(vdev, &state);
> +	if (ret) {
> +		dev_err(vf_dev, "failed to get device migration state");

Isn't the errno below sufficient?  No need to add the ability to fill
logs as well.

> +		return -EINVAL;
> +	}
> +
> +	switch (state) {
> +	case VFIO_DEVICE_STATE_RUNNING:
> +		seq_printf(seq, "%s\n", "RUNNING");
> +		break;
> +	case VFIO_DEVICE_STATE_STOP_COPY:
> +		seq_printf(seq, "%s\n", "STOP_COPY");
> +		break;
> +	case VFIO_DEVICE_STATE_STOP:
> +		seq_printf(seq, "%s\n", "STOP");
> +		break;
> +	case VFIO_DEVICE_STATE_RESUMING:
> +		seq_printf(seq, "%s\n", "RESUMING");
> +		break;
> +	case VFIO_DEVICE_STATE_RUNNING_P2P:
> +		seq_printf(seq, "%s\n", "RESUMING_P2P");
> +		break;
> +	case VFIO_DEVICE_STATE_ERROR:
> +		seq_printf(seq, "%s\n", "ERROR");
> +		break;
> +	default:
> +		seq_printf(seq, "%s\n", "Invalid");
> +	}
> +
> +	return 0;
> +}
> +
> +void vfio_vf_debugfs_init(struct vfio_device *vdev)
> +{
> +	struct device *dev = &vdev->device;
> +
> +	vdev->debug_root = debugfs_create_dir(dev_name(vdev->dev), vfio_debugfs_root);
> +
> +	debugfs_create_devm_seqfile(dev, "migration_state", vdev->debug_root,
> +				  vfio_vf_state_read);
> +}
> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_init);
> +
> +void vfio_vf_debugfs_exit(struct vfio_device *vdev)
> +{
> +	debugfs_remove_recursive(vdev->debug_root);
> +}
> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_exit);

The above two should probably be vfio_device_debugfs_{init,exit}().

> +
> +void  vfio_debugfs_create_root(void)
> +{
> +	vfio_debugfs_root = debugfs_create_dir("vfio", NULL);
> +}
> +EXPORT_SYMBOL_GPL(vfio_debugfs_create_root);
> +
> +void  vfio_debugfs_remove_root(void)
> +{
> +	debugfs_remove_recursive(vfio_debugfs_root);
> +	vfio_debugfs_root = NULL;
> +}
> +EXPORT_SYMBOL_GPL(vfio_debugfs_remove_root);

As Jason notes, this becomes part of the vfio module, these latter two
don't need to be exported to be called by vfio_main.

Thanks,
Alex

> +
> diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
> index 3a597e799918..09772fd3a396 100644
> --- a/drivers/vfio/vfio_main.c
> +++ b/drivers/vfio/vfio_main.c
> @@ -1408,6 +1408,9 @@ static int __init vfio_init(void)
>  	}
>  
>  	pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
> +
> +	vfio_debugfs_create_root();
> +
>  	return 0;
>  
>  err_dev_class:
> @@ -1425,6 +1428,8 @@ static void __exit vfio_cleanup(void)
>  	vfio_virqfd_exit();
>  	vfio_group_cleanup();
>  	xa_destroy(&vfio_device_set_xa);
> +
> +	vfio_debugfs_remove_root();
>  }
>  
>  module_init(vfio_init);
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index 93134b023968..fa6b898ebb58 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -63,6 +63,14 @@ struct vfio_device {
>  	struct iommufd_ctx *iommufd_ictx;
>  	bool iommufd_attached;
>  #endif
> +
> +#ifdef CONFIG_DEBUG_FS
> +	/*
> +	 * debug_root is a static property of the vfio_device
> +	 * which must be set prior to registering the vfio_device.
> +	 */
> +	struct dentry *debug_root;
> +#endif
>  };
>  
>  /**

Re: [PATCH v8 2/5] hisi_acc_vfio_pci: extract public functions for container_of

[Alex Williamson]

On Fri, 17 Feb 2023 16:48:28 +0800
Longfang Liu <liulongfang@huawei.com> wrote:

> In the current driver, vdev is obtained from struct
> hisi_acc_vf_core_device through the container_of function.
> This method is used in many places in the driver. In order to
> reduce this repetitive operation, I extracted a public function
> to replace it.
> 
> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
> ---
>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 21 ++++++++++---------
>  1 file changed, 11 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> index a117eaf21c14..a1589947e721 100644
> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> @@ -630,6 +630,12 @@ static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vde
>  	}
>  }
>  
> +static struct hisi_acc_vf_core_device *hisi_acc_get_vf_dev(struct vfio_device *vdev)
> +{
> +	return container_of(vdev, struct hisi_acc_vf_core_device,
> +			    core_device.vdev);
> +}

This type of function is often named to_foo_bar(), ex. to_pci_dev(),
and often macros.  Perhaps:

#define to_hisi_acc_dev(n) container_of(n, \
	struct hisi_acc_vf_core_device, core_device,vdev)

Thanks,
Alex

> +
>  /*
>   * This function is called in all state_mutex unlock cases to
>   * handle a 'deferred_reset' if exists.
> @@ -1042,8 +1048,7 @@ static struct file *
>  hisi_acc_vfio_pci_set_device_state(struct vfio_device *vdev,
>  				   enum vfio_device_mig_state new_state)
>  {
> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(vdev,
> -			struct hisi_acc_vf_core_device, core_device.vdev);
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>  	enum vfio_device_mig_state next_state;
>  	struct file *res = NULL;
>  	int ret;
> @@ -1084,8 +1089,7 @@ static int
>  hisi_acc_vfio_pci_get_device_state(struct vfio_device *vdev,
>  				   enum vfio_device_mig_state *curr_state)
>  {
> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(vdev,
> -			struct hisi_acc_vf_core_device, core_device.vdev);
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>  
>  	mutex_lock(&hisi_acc_vdev->state_mutex);
>  	*curr_state = hisi_acc_vdev->mig_state;
> @@ -1301,8 +1305,7 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
>  
>  static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
>  {
> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev,
> -			struct hisi_acc_vf_core_device, core_device.vdev);
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
>  	struct vfio_pci_core_device *vdev = &hisi_acc_vdev->core_device;
>  	int ret;
>  
> @@ -1325,8 +1328,7 @@ static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
>  
>  static void hisi_acc_vfio_pci_close_device(struct vfio_device *core_vdev)
>  {
> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev,
> -			struct hisi_acc_vf_core_device, core_device.vdev);
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
>  	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
>  
>  	iounmap(vf_qm->io_base);
> @@ -1341,8 +1343,7 @@ static const struct vfio_migration_ops hisi_acc_vfio_pci_migrn_state_ops = {
>  
>  static int hisi_acc_vfio_pci_migrn_init_dev(struct vfio_device *core_vdev)
>  {
> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev,
> -			struct hisi_acc_vf_core_device, core_device.vdev);
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
>  	struct pci_dev *pdev = to_pci_dev(core_vdev->dev);
>  	struct hisi_qm *pf_qm = hisi_acc_get_pf_qm(pdev);
>  

Re: [PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

[Alex Williamson]

On Fri, 17 Feb 2023 16:48:29 +0800
Longfang Liu <liulongfang@huawei.com> wrote:

> On the debugfs framework of VFIO, if the CONFIG_DEBUG_FS macro is
> enabled, the debug function is registered for the live migration driver
> of the HiSilicon accelerator device.
> 
> On the basis of the original public debug function, a private debug
> function is added:
> 
> mig_data file: used to get the migration data of the live migration device
> mig_attr file: used to get device attributes of the live migration device
> debug file: used to test for acquiring and writing device state data
> for VF device.
> 
> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
> ---
>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 282 ++++++++++++++++++
>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h    |  11 +
>  2 files changed, 293 insertions(+)
> 
> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> index a1589947e721..a0ecb1cd5707 100644
> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> @@ -15,6 +15,7 @@
>  #include <linux/anon_inodes.h>
>  
>  #include "hisi_acc_vfio_pci.h"
> +#include "../../vfio.h"
>  
>  /* Return 0 on VM acc device ready, -ETIMEDOUT hardware timeout */
>  static int qm_wait_dev_not_ready(struct hisi_qm *qm)
> @@ -606,6 +607,18 @@ hisi_acc_check_int_state(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>  	}
>  }
>  
> +static void hisi_acc_vf_migf_save(struct hisi_acc_vf_migration_file *src_migf,
> +	struct hisi_acc_vf_migration_file *dst_migf)
> +{
> +	if (!dst_migf)
> +		return;
> +
> +	dst_migf->disabled = false;
> +	dst_migf->total_length = src_migf->total_length;
> +	memcpy(&dst_migf->vf_data, &src_migf->vf_data,
> +		    sizeof(struct acc_vf_data));
> +}
> +
>  static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
>  {
>  	mutex_lock(&migf->lock);
> @@ -618,12 +631,16 @@ static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
>  static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>  {
>  	if (hisi_acc_vdev->resuming_migf) {
> +		hisi_acc_vf_migf_save(hisi_acc_vdev->resuming_migf,
> +						hisi_acc_vdev->debug_migf);
>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->resuming_migf);
>  		fput(hisi_acc_vdev->resuming_migf->filp);
>  		hisi_acc_vdev->resuming_migf = NULL;
>  	}
>  
>  	if (hisi_acc_vdev->saving_migf) {
> +		hisi_acc_vf_migf_save(hisi_acc_vdev->saving_migf,
> +						hisi_acc_vdev->debug_migf);
>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->saving_migf);
>  		fput(hisi_acc_vdev->saving_migf->filp);
>  		hisi_acc_vdev->saving_migf = NULL;
> @@ -1303,6 +1320,265 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
>  	return vfio_pci_core_ioctl(core_vdev, cmd, arg);
>  }
>  
> +static int hisi_acc_vf_debug_io(struct vfio_device *vdev)
> +{
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> +	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
> +	struct device *dev = vdev->dev;
> +	u64 data;
> +	int ret;
> +
> +	ret = qm_wait_dev_not_ready(vf_qm);
> +	if (ret)
> +		dev_err(dev, "VF device not ready!\n");
> +
> +	data = readl(vf_qm->io_base + QM_MB_CMD_SEND_BASE);
> +	dev_info(dev, "debug mailbox val: 0x%llx\n", data);
> +
> +	return ret;
> +}
> +
> +static int hisi_acc_vf_debug_resume(struct vfio_device *vdev)
> +{
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
> +	struct device *dev = vdev->dev;
> +	int ret;
> +
> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
> +	if (ret) {
> +		dev_err(dev, "failed to save device data!\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = vf_qm_check_match(hisi_acc_vdev, migf);
> +	if (ret) {
> +		dev_err(dev, "failed to match the VF!\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = vf_qm_load_data(hisi_acc_vdev, migf);
> +	if (ret) {
> +		dev_err(dev, "failed to recover the VF!\n");
> +		return -EINVAL;
> +	}
> +
> +	vf_qm_fun_reset(&hisi_acc_vdev->vf_qm);
> +	dev_info(dev, "successful to resume device data!\n");
> +
> +	return 0;
> +}
> +
> +static int hisi_acc_vf_debug_save(struct vfio_device *vdev)
> +{
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
> +	struct device *dev = vdev->dev;
> +	int ret;
> +
> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
> +	if (ret) {
> +		dev_err(dev, "failed to save device data!\n");
> +		return -EINVAL;
> +	}
> +	dev_info(dev, "successful to save device data!\n");
> +
> +	return 0;
> +}
> +
> +static int
> +hisi_acc_vf_debug_operate(struct vfio_device *vdev, unsigned int cmd)
> +{
> +	int ret;
> +
> +	switch (cmd) {
> +	case STATE_SAVE:
> +		ret = hisi_acc_vf_debug_save(vdev);
> +		if (ret)
> +			return ret;
> +		break;
> +	case STATE_RESUME:
> +		ret = hisi_acc_vf_debug_resume(vdev);
> +		if (ret)
> +			return ret;
> +		break;
> +	case RW_IO_TEST:
> +		ret = hisi_acc_vf_debug_io(vdev);
> +		if (ret)
> +			return ret;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int hisi_acc_vf_debug_check(struct vfio_device *vdev)
> +{
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
> +	enum vfio_device_mig_state state;
> +
> +	if (!vdev->mig_ops || !migf) {
> +		dev_err(vdev->dev, "device not support debugfs!\n");
> +		return -EINVAL;
> +	}
> +
> +	/* If device not opened, the debugfs operation will trigger calltrace */
> +	(void)vdev->mig_ops->migration_get_state(vdev, &state);
> +	if (state == VFIO_DEVICE_STATE_ERROR ||
> +	    state == VFIO_DEVICE_STATE_STOP) {
> +		dev_err(vdev->dev, "device not opened!\n");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static ssize_t hisi_acc_vf_debug_write(struct file *filp, const char __user *buffer,
> +			    size_t count, loff_t *pos)
> +{
> +	struct vfio_device	*vdev = filp->private_data;
> +	char tbuf[VFIO_DEV_DBG_LEN];
> +	unsigned long cmd;
> +	int len, ret;
> +
> +	if (*pos)
> +		return 0;
> +
> +	if (count >= VFIO_DEV_DBG_LEN)
> +		return -ENOSPC;
> +
> +	ret = hisi_acc_vf_debug_check(vdev);
> +	if (ret)
> +		return -EINVAL;
> +
> +	len = simple_write_to_buffer(tbuf, VFIO_DEV_DBG_LEN - 1,
> +					pos, buffer, count);
> +	if (len < 0 || len > VFIO_DEV_DBG_LEN - 1)
> +		return -EINVAL;
> +	tbuf[len] = '\0';
> +	if (kstrtoul(tbuf, 0, &cmd))
> +		return -EFAULT;
> +
> +	ret = hisi_acc_vf_debug_operate(vdev, cmd);
> +	if (ret) {
> +		dev_err(vdev->dev, "device debug test failed!\n");
> +		return -EINVAL;
> +	}
> +
> +	return count;
> +}
> +
> +static const struct file_operations hisi_acc_vf_debug_fops = {
> +	.owner = THIS_MODULE,
> +	.open = simple_open,
> +	.write = hisi_acc_vf_debug_write,
> +};
> +
> +static void seq_print_hex_data(struct seq_file *seq, const void *buf, size_t len)
> +{
> +#define HEX_LINE_SIZE		131
> +#define HEX_ROW_SIZE		16
> +	unsigned char linebuf[HEX_LINE_SIZE];
> +	int i, linelen, remaining = len;
> +	const u8 *ptr = buf;
> +
> +	for (i = 0; i < len; i += HEX_ROW_SIZE) {
> +		linelen = min(remaining, HEX_ROW_SIZE);
> +		remaining -= HEX_ROW_SIZE;
> +
> +		hex_dump_to_buffer(ptr + i, linelen, HEX_ROW_SIZE, 1,
> +					linebuf, sizeof(linebuf), false);
> +
> +		seq_printf(seq, "%s%.8x: %s\n", "Mig Data:", i, linebuf);
> +	}
> +}
> +
> +static int hisi_acc_vf_data_read(struct seq_file *seq, void *data)
> +{
> +	struct device *vf_dev = seq->private;
> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
> +	struct vfio_device	*vdev = &core_device->vdev;
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
> +	size_t vf_data_sz = offsetofend(struct acc_vf_data, padding);
> +
> +	if (debug_migf && debug_migf->total_length)
> +		seq_print_hex_data(seq, (unsigned char *)&debug_migf->vf_data,
> +				vf_data_sz);
> +	else
> +		seq_printf(seq, "%s\n", "device not migrated!");
> +
> +	return 0;
> +}
> +
> +static int hisi_acc_vf_attr_read(struct seq_file *seq, void *data)
> +{
> +	struct device *vf_dev = seq->private;
> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
> +	struct vfio_device	*vdev = &core_device->vdev;
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
> +
> +	if (debug_migf && debug_migf->total_length) {
> +		seq_printf(seq,
> +			 "acc device:\n"
> +			 "device  state: %d\n"
> +			 "device  ready: %u\n"
> +			 "data    valid: %d\n"
> +			 "data     size: %lu\n",
> +			 hisi_acc_vdev->mig_state,
> +			 hisi_acc_vdev->vf_qm_state,
> +			 debug_migf->disabled,
> +			 debug_migf->total_length);
> +	} else {
> +		seq_printf(seq, "%s\n", "device not migrated!");
> +	}
> +
> +	return 0;
> +}
> +
> +static int hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vdev)
> +{
> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
> +	struct device *dev = vdev->dev;
> +	void *migf = NULL;
> +
> +	if (!debugfs_initialized())
> +		return 0;
> +
> +	vfio_vf_debugfs_init(vdev);
> +
> +	migf = kzalloc(sizeof(struct hisi_acc_vf_migration_file), GFP_KERNEL);
> +	if (!migf)
> +		return -ENOMEM;
> +
> +	hisi_acc_vdev->debug_migf = migf;
> +
> +	debugfs_create_devm_seqfile(dev, "migration_data", vdev->debug_root,
> +				  hisi_acc_vf_data_read);
> +	debugfs_create_devm_seqfile(dev, "migration_attr", vdev->debug_root,
> +				  hisi_acc_vf_attr_read);
> +
> +	debugfs_create_file("migration_debug", 0200, vdev->debug_root,
> +				  vdev, &hisi_acc_vf_debug_fops);
> +

All of these are going to be device specific, right?  So do we really
want a debugfs file structure that looks like:

vfio
└── migration
    ├── hisi_acc
    │   ├── attr
    │   ├── data
    │   └── debug
    └── state

Thanks,
Alex

> +	return 0;
> +}
> +
> +static void hisi_acc_vf_debugfs_exit(struct hisi_acc_vf_core_device *hisi_acc_vdev)
> +{
> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
> +
> +	if (!debugfs_initialized())
> +		return;
> +
> +	vfio_vf_debugfs_exit(vdev);
> +	kfree(hisi_acc_vdev->debug_migf);
> +}
> +
>  static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
>  {
>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
> @@ -1416,6 +1692,9 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>  	if (IS_ERR(hisi_acc_vdev))
>  		return PTR_ERR(hisi_acc_vdev);
>  
> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
> +		hisi_acc_vfio_debug_init(hisi_acc_vdev);
> +
>  	dev_set_drvdata(&pdev->dev, &hisi_acc_vdev->core_device);
>  	ret = vfio_pci_core_register_device(&hisi_acc_vdev->core_device);
>  	if (ret)
> @@ -1423,6 +1702,8 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>  	return 0;
>  
>  out_put_vdev:
> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
> +		hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
>  	return ret;
>  }
> @@ -1431,6 +1712,7 @@ static void hisi_acc_vfio_pci_remove(struct pci_dev *pdev)
>  {
>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_drvdata(pdev);
>  
> +	hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
>  	vfio_pci_core_unregister_device(&hisi_acc_vdev->core_device);
>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
>  }
> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
> index dcabfeec6ca1..ef50b12f018d 100644
> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
> @@ -49,6 +49,14 @@
>  #define QM_EQC_DW0		0X8000
>  #define QM_AEQC_DW0		0X8020
>  
> +#define VFIO_DEV_DBG_LEN		256
> +
> +enum mig_debug_cmd {
> +	STATE_SAVE,
> +	STATE_RESUME,
> +	RW_IO_TEST,
> +};
> +
>  struct acc_vf_data {
>  #define QM_MATCH_SIZE offsetofend(struct acc_vf_data, qm_rsv_state)
>  	/* QM match information */
> @@ -113,5 +121,8 @@ struct hisi_acc_vf_core_device {
>  	spinlock_t reset_lock;
>  	struct hisi_acc_vf_migration_file *resuming_migf;
>  	struct hisi_acc_vf_migration_file *saving_migf;
> +
> +	/* For debugfs */
> +	struct hisi_acc_vf_migration_file *debug_migf;
>  };
>  #endif /* HISI_ACC_VFIO_PCI_H */

Re: [PATCH v8 1/5] vfio/migration: Add debugfs to live migration driver

[liulongfang]

On 2023/3/11 1:12, Jason Gunthorpe wrote:
> On Fri, Feb 17, 2023 at 04:48:27PM +0800, Longfang Liu wrote:
>> +void vfio_vf_debugfs_init(struct vfio_device *vdev)
>> +{
>> +	struct device *dev = &vdev->device;
>> +
>> +	vdev->debug_root = debugfs_create_dir(dev_name(vdev->dev), vfio_debugfs_root);
>> +
>> +	debugfs_create_devm_seqfile(dev, "migration_state", vdev->debug_root,
>> +				  vfio_vf_state_read);
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_init);
>> +
>> +void vfio_vf_debugfs_exit(struct vfio_device *vdev)
>> +{
>> +	debugfs_remove_recursive(vdev->debug_root);
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_exit);
>> +
>> +void  vfio_debugfs_create_root(void)
>> +{
>> +	vfio_debugfs_root = debugfs_create_dir("vfio", NULL);
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_debugfs_create_root);
>> +
>> +void  vfio_debugfs_remove_root(void)
>> +{
>> +	debugfs_remove_recursive(vfio_debugfs_root);
>> +	vfio_debugfs_root = NULL;
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_debugfs_remove_root);
> 
> Why are these symbols exported?
> 

If the export statement is not added, a compilation error will occur:

ERROR: modpost: "vfio_vf_debugfs_init" [drivers/vfio/pci/hisilicon/hisi-acc-vfio-pci.ko] undefined!
ERROR: modpost: "vfio_vf_debugfs_exit" [drivers/vfio/pci/hisilicon/hisi-acc-vfio-pci.ko] undefined!
scripts/Makefile.modpost:126: recipe for target 'Module.symvers' failed
make[1]: *** [Module.symvers] Error 1


> Jason
> 
> .
Thanks,
Longfang

> 

Re: [PATCH v8 1/5] vfio/migration: Add debugfs to live migration driver

[liulongfang]

On 2023/3/11 7:40, Alex Williamson wrote:
> On Fri, 17 Feb 2023 16:48:27 +0800
> Longfang Liu <liulongfang@huawei.com> wrote:
> 
>> There are multiple devices, software and operational steps involved
>> in the process of live migration. An error occurred on any node may
>> cause the live migration operation to fail.
>> This complex process makes it very difficult to locate and analyze
>> the cause when the function fails.
>>
>> In order to quickly locate the cause of the problem when the
>> live migration fails, I added a set of debugfs to the vfio
>> live migration driver.
>>                                +-------------------------------------------+
>>                                |                                           |
>>                                |                                           |
>>                                |                  QEMU                     |
>>                                |                                           |
>>                                |                                           |
>>                                +---+----------------------------+----------+
>>                                    |      ^                     |      ^
>>                                    |      |                     |      |
>>  +--------+                        |      |                     |      |
>>  |  vfio  |                        v      |                     v      |
>>  +--------+                     +---------+--+               +---------+--+
>>      ^                          |src vfio_dev|               |dst vfio_dev|
>>      |                          +--+---------+               +--+---------+
>>      |                             |      ^                     |      ^
>>      |                             |      |                     |      |
>>      |                             v      |                     |      |
>>      |  +-----------+         +-----------+----+                |      |
>>      +--+<bdf>file_x+<----+---+migration_attr  |                |      |
>>      |  +-----------+     |   +----------------+                |      |
>>      |                    +---+migration_data  |                |      |
>>      |                    |   +----------------+                |      |
>>      |                    +---+migration_debug |                |      |
>>      |                    |   +----------------+                |      |
>>      |                    |   +----------------+                |      |
>>      |                    +---+migration_state |                |      |
>>      |                        +----------------+                |      |
>>      |                                                          |      |
>>      |  +-----------+         +----------------+                |      |
>>      +--+<bdf>file_y|<----+---+migration_attr  |                |      |
>>         +-----------+     |   +----------------+                |      |
>>                           +---+migration_data  |                |      |
>>                           |   +----------------+<---------------+      |
>>                           +---+migration_debug |                       |
>>                           |   +----------------+                       |
>>                           |   +----------------+                       |
>>                           +---+migration_state +-----------------------+
>>                               +----------------+
>>
>> The entire debugfs directory will be based on the definition of
>> the CONFIG_DEBUG_FS macro. If this macro is not enabled, the
>> interfaces in vfio.h will be empty definitions, and the creation
>> and initialization of the debugfs directory will not be executed.
>>
>> debugfs will create a public root directory "vfio" file.
>> then create a device <bdf> named file for each live migration device.
> 
> dev_name(), it's only <sbdf> for PCI devices.
> 
Yes, this description needs revision.

>> First, create a unified state acquisition file of "migration_state"
>> in this device directory.
>> Then, create your own debugging files independently according to
>> the functional requirements of each device.
>>
>> Here, HiSilicon accelerator creates three debug files:
>> migration_attr: used to obtain the attribute parameters of the
>> current live migration device.
>> migration_data: used to get the live migration data of the current
>> live migration device.
>> migration_debug: Used to debug the current live migration device
>> through commands.
>>
>> The live migration function of the current device can be tested by
>> operating the debug files, and the functional status of the equipment
>> and software at each stage can be tested step by step without
>> performing the complete live migration function. And after the live
>> migration is performed, the migration device data of the live migration
>> can be obtained through the debug files.
>>
>> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
>> ---
>>  drivers/vfio/Makefile       |  2 +-
>>  drivers/vfio/vfio.h         | 14 +++++++
>>  drivers/vfio/vfio_debugfs.c | 82 +++++++++++++++++++++++++++++++++++++
>>  drivers/vfio/vfio_main.c    |  5 +++
>>  include/linux/vfio.h        |  8 ++++
>>  5 files changed, 110 insertions(+), 1 deletion(-)
>>  create mode 100644 drivers/vfio/vfio_debugfs.c
>>
>> diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile
>> index 70e7dcb302ef..1debcff31d30 100644
>> --- a/drivers/vfio/Makefile
>> +++ b/drivers/vfio/Makefile
>> @@ -7,7 +7,7 @@ vfio-y += vfio_main.o \
>>  vfio-$(CONFIG_IOMMUFD) += iommufd.o
>>  vfio-$(CONFIG_VFIO_CONTAINER) += container.o
>>  vfio-$(CONFIG_VFIO_VIRQFD) += virqfd.o
>> -
>> +vfio-$(CONFIG_DEBUG_FS) += vfio_debugfs.o
>>  obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o
>>  obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o
>>  obj-$(CONFIG_VFIO_PCI) += pci/
>> diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h
>> index e9721d8424bc..66c00f97e9cc 100644
>> --- a/drivers/vfio/vfio.h
>> +++ b/drivers/vfio/vfio.h
>> @@ -258,4 +258,18 @@ static inline void vfio_device_put_kvm(struct vfio_device *device)
>>  }
>>  #endif
>>  
>> +#ifdef CONFIG_DEBUG_FS
>> +void vfio_debugfs_create_root(void);
>> +void vfio_debugfs_remove_root(void);
>> +
>> +void vfio_vf_debugfs_init(struct vfio_device *vdev);
>> +void vfio_vf_debugfs_exit(struct vfio_device *vdev);
> 
> s/vf_// throughout.
> 
Yes, it is not vf anymore, the function name needs to be modified

>> +#else
>> +static inline void vfio_debugfs_create_root(void) { }
>> +static inline void vfio_debugfs_remove_root(void) { }
>> +
>> +static inline void vfio_vf_debugfs_init(struct vfio_device *vdev) { }
>> +static inline void vfio_vf_debugfs_exit(struct vfio_device *vdev) { }
>> +#endif /* CONFIG_DEBUG_FS */
>> +
>>  #endif
>> diff --git a/drivers/vfio/vfio_debugfs.c b/drivers/vfio/vfio_debugfs.c
>> new file mode 100644
>> index 000000000000..c5df1496fe0e
>> --- /dev/null
>> +++ b/drivers/vfio/vfio_debugfs.c
>> @@ -0,0 +1,82 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (c) 2023, HiSilicon Ltd.
>> + */
>> +
>> +#include <linux/device.h>
>> +#include <linux/debugfs.h>
>> +#include <linux/seq_file.h>
>> +#include <linux/vfio.h>
>> +#include "vfio.h"
>> +
>> +static struct dentry *vfio_debugfs_root;
>> +
>> +static int vfio_vf_state_read(struct seq_file *seq, void *data)
>> +{
>> +	struct device *vf_dev = seq->private;
>> +	struct vfio_device *vdev = container_of(vf_dev, struct vfio_device, device);
>> +	enum vfio_device_mig_state state;
>> +	int ret;
>> +
>> +	ret = vdev->mig_ops->migration_get_state(vdev, &state);
>> +	if (ret) {
>> +		dev_err(vf_dev, "failed to get device migration state");
> 
> Isn't the errno below sufficient?  No need to add the ability to fill
> logs as well.
> 
OK，I will remove it in the next version.

>> +		return -EINVAL;
>> +	}
>> +
>> +	switch (state) {
>> +	case VFIO_DEVICE_STATE_RUNNING:
>> +		seq_printf(seq, "%s\n", "RUNNING");
>> +		break;
>> +	case VFIO_DEVICE_STATE_STOP_COPY:
>> +		seq_printf(seq, "%s\n", "STOP_COPY");
>> +		break;
>> +	case VFIO_DEVICE_STATE_STOP:
>> +		seq_printf(seq, "%s\n", "STOP");
>> +		break;
>> +	case VFIO_DEVICE_STATE_RESUMING:
>> +		seq_printf(seq, "%s\n", "RESUMING");
>> +		break;
>> +	case VFIO_DEVICE_STATE_RUNNING_P2P:
>> +		seq_printf(seq, "%s\n", "RESUMING_P2P");
>> +		break;
>> +	case VFIO_DEVICE_STATE_ERROR:
>> +		seq_printf(seq, "%s\n", "ERROR");
>> +		break;
>> +	default:
>> +		seq_printf(seq, "%s\n", "Invalid");
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +void vfio_vf_debugfs_init(struct vfio_device *vdev)
>> +{
>> +	struct device *dev = &vdev->device;
>> +
>> +	vdev->debug_root = debugfs_create_dir(dev_name(vdev->dev), vfio_debugfs_root);
>> +
>> +	debugfs_create_devm_seqfile(dev, "migration_state", vdev->debug_root,
>> +				  vfio_vf_state_read);
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_init);
>> +
>> +void vfio_vf_debugfs_exit(struct vfio_device *vdev)
>> +{
>> +	debugfs_remove_recursive(vdev->debug_root);
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_exit);
> 
> The above two should probably be vfio_device_debugfs_{init,exit}().
> 
OK

>> +
>> +void  vfio_debugfs_create_root(void)
>> +{
>> +	vfio_debugfs_root = debugfs_create_dir("vfio", NULL);
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_debugfs_create_root);
>> +
>> +void  vfio_debugfs_remove_root(void)
>> +{
>> +	debugfs_remove_recursive(vfio_debugfs_root);
>> +	vfio_debugfs_root = NULL;
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_debugfs_remove_root);
> 
> As Jason notes, this becomes part of the vfio module, these latter two
> don't need to be exported to be called by vfio_main.
> 

Let me re-debug to see if I can delete the following exports

> Thanks,
> Alex
> 
Thanks，
Longfang

>> +
>> diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
>> index 3a597e799918..09772fd3a396 100644
>> --- a/drivers/vfio/vfio_main.c
>> +++ b/drivers/vfio/vfio_main.c
>> @@ -1408,6 +1408,9 @@ static int __init vfio_init(void)
>>  	}
>>  
>>  	pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
>> +
>> +	vfio_debugfs_create_root();
>> +
>>  	return 0;
>>  
>>  err_dev_class:
>> @@ -1425,6 +1428,8 @@ static void __exit vfio_cleanup(void)
>>  	vfio_virqfd_exit();
>>  	vfio_group_cleanup();
>>  	xa_destroy(&vfio_device_set_xa);
>> +
>> +	vfio_debugfs_remove_root();
>>  }
>>  
>>  module_init(vfio_init);
>> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
>> index 93134b023968..fa6b898ebb58 100644
>> --- a/include/linux/vfio.h
>> +++ b/include/linux/vfio.h
>> @@ -63,6 +63,14 @@ struct vfio_device {
>>  	struct iommufd_ctx *iommufd_ictx;
>>  	bool iommufd_attached;
>>  #endif
>> +
>> +#ifdef CONFIG_DEBUG_FS
>> +	/*
>> +	 * debug_root is a static property of the vfio_device
>> +	 * which must be set prior to registering the vfio_device.
>> +	 */
>> +	struct dentry *debug_root;
>> +#endif
>>  };
>>  
>>  /**
> 
> .
> 

Re: [PATCH v8 2/5] hisi_acc_vfio_pci: extract public functions for container_of

[liulongfang]

On 2023/3/11 7:40, Alex Williamson wrote:
> On Fri, 17 Feb 2023 16:48:28 +0800
> Longfang Liu <liulongfang@huawei.com> wrote:
> 
>> In the current driver, vdev is obtained from struct
>> hisi_acc_vf_core_device through the container_of function.
>> This method is used in many places in the driver. In order to
>> reduce this repetitive operation, I extracted a public function
>> to replace it.
>>
>> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
>> ---
>>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 21 ++++++++++---------
>>  1 file changed, 11 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> index a117eaf21c14..a1589947e721 100644
>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> @@ -630,6 +630,12 @@ static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vde
>>  	}
>>  }
>>  
>> +static struct hisi_acc_vf_core_device *hisi_acc_get_vf_dev(struct vfio_device *vdev)
>> +{
>> +	return container_of(vdev, struct hisi_acc_vf_core_device,
>> +			    core_device.vdev);
>> +}
> 
> This type of function is often named to_foo_bar(), ex. to_pci_dev(),
> and often macros.  Perhaps:
> 
> #define to_hisi_acc_dev(n) container_of(n, \
> 	struct hisi_acc_vf_core_device, core_device,vdev)
>

First of all, thanks for your suggestion, but I want to keep
the current way of complete function declaration.

Thanks,
Longfang.
> Thanks,
> Alex
> 
>> +
>>  /*
>>   * This function is called in all state_mutex unlock cases to
>>   * handle a 'deferred_reset' if exists.
>> @@ -1042,8 +1048,7 @@ static struct file *
>>  hisi_acc_vfio_pci_set_device_state(struct vfio_device *vdev,
>>  				   enum vfio_device_mig_state new_state)
>>  {
>> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(vdev,
>> -			struct hisi_acc_vf_core_device, core_device.vdev);
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>  	enum vfio_device_mig_state next_state;
>>  	struct file *res = NULL;
>>  	int ret;
>> @@ -1084,8 +1089,7 @@ static int
>>  hisi_acc_vfio_pci_get_device_state(struct vfio_device *vdev,
>>  				   enum vfio_device_mig_state *curr_state)
>>  {
>> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(vdev,
>> -			struct hisi_acc_vf_core_device, core_device.vdev);
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>  
>>  	mutex_lock(&hisi_acc_vdev->state_mutex);
>>  	*curr_state = hisi_acc_vdev->mig_state;
>> @@ -1301,8 +1305,7 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
>>  
>>  static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
>>  {
>> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev,
>> -			struct hisi_acc_vf_core_device, core_device.vdev);
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
>>  	struct vfio_pci_core_device *vdev = &hisi_acc_vdev->core_device;
>>  	int ret;
>>  
>> @@ -1325,8 +1328,7 @@ static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
>>  
>>  static void hisi_acc_vfio_pci_close_device(struct vfio_device *core_vdev)
>>  {
>> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev,
>> -			struct hisi_acc_vf_core_device, core_device.vdev);
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
>>  	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
>>  
>>  	iounmap(vf_qm->io_base);
>> @@ -1341,8 +1343,7 @@ static const struct vfio_migration_ops hisi_acc_vfio_pci_migrn_state_ops = {
>>  
>>  static int hisi_acc_vfio_pci_migrn_init_dev(struct vfio_device *core_vdev)
>>  {
>> -	struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev,
>> -			struct hisi_acc_vf_core_device, core_device.vdev);
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
>>  	struct pci_dev *pdev = to_pci_dev(core_vdev->dev);
>>  	struct hisi_qm *pf_qm = hisi_acc_get_pf_qm(pdev);
>>  
> 
> .
> 

Re: [PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

[liulongfang]

On 2023/3/11 1:22, Jason Gunthorpe wrote:
> On Fri, Feb 17, 2023 at 04:48:29PM +0800, Longfang Liu wrote:
> 
>> +static int hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>> +{
>> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
>> +	struct device *dev = vdev->dev;
>> +	void *migf = NULL;
>> +
>> +	if (!debugfs_initialized())
>> +		return 0;
>> +
>> +	vfio_vf_debugfs_init(vdev);
> 
> This is weirdly named with _vf_, this is just
> vfio_device_debufs_init()
> 
OK,

Thanks,
Longfang.
> Jason
> .
> 

Re: [PATCH v8 4/5] Documentation: add debugfs description for vfio

[liulongfang]

On 2023/3/11 7:39, Alex Williamson wrote:
> On Fri, 17 Feb 2023 16:48:30 +0800
> Longfang Liu <liulongfang@huawei.com> wrote:
> 
>> Add two debugfs document description file to help users understand
>> how to use the accelerator live migration driver's debugfs.
>>
>> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
>> ---
>>  .../ABI/testing/debugfs-hisi-migration        | 28 +++++++++++++++++++
>>  Documentation/ABI/testing/debugfs-vfio        | 17 +++++++++++
>>  2 files changed, 45 insertions(+)
>>  create mode 100644 Documentation/ABI/testing/debugfs-hisi-migration
>>  create mode 100644 Documentation/ABI/testing/debugfs-vfio
>>
>> diff --git a/Documentation/ABI/testing/debugfs-hisi-migration b/Documentation/ABI/testing/debugfs-hisi-migration
>> new file mode 100644
>> index 000000000000..0f45f30ff6d4
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/debugfs-hisi-migration
>> @@ -0,0 +1,28 @@
>> +What:		/sys/kernel/debug/vfio/<bdf>/migration_data
> 
> s/bdf/name/ throughout.
> 
OK, I will change it in the next version.

>> +Date:		Feb 2023
>> +KernelVersion:  6.2
>> +Contact:	linux-kernel@vger.kernel.org
> 
> Is there not someone at Huawei willing to be the contact point for the
> hisi_acc specific attributes?
> 

Sorry, I misunderstood here.
Before, I thought it could only be the contact information of the public community.
I will add my email address in the next version.

>> +Description:	Read the live migration data of the vfio device.
>> +		The output format of the data is defined by the live
>> +		migration driver.
>> +
>> +What:		/sys/kernel/debug/vfio/<bdf>/migration_attr
>> +Date:		Feb 2023
>> +KernelVersion:  6.2
>> +Contact:	linux-kernel@vger.kernel.org
>> +Description:	Read the live migration attributes of the vfio device.
>> +		The output format of the attributes is defined by the live
>> +		migration driver.
>> +
>> +What:		/sys/kernel/debug/vfio/<bdf>/migration_debug
>> +Date:		Feb 2023
>> +KernelVersion:  6.2
>> +Contact:	linux-kernel@vger.kernel.org
>> +Description:	This debug file supports "echo" command	write operations.
>> +		The command is actually represented by an integer number, and the
>> +		specific meaning is defined by the corresponding device driver.
>> +		For example, three commands are defined in the HiSilicon accelerator
>> +		live migration driver:
>> +		0: State save
>> +		1: State resume
>> +		2: IO test
>> diff --git a/Documentation/ABI/testing/debugfs-vfio b/Documentation/ABI/testing/debugfs-vfio
>> new file mode 100644
>> index 000000000000..e22531d16674
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/debugfs-vfio
>> @@ -0,0 +1,17 @@
>> +What:		/sys/kernel/debug/vfio
>> +Date:		Feb 2023
>> +KernelVersion:  6.2
>> +Contact:	linux-kernel@vger.kernel.org
> 
> These should likely at least be the kvm list as the official list of
> vfio if you're not interested in being the contact point.
> 

I misunderstood here.
I will add my email address in the next version.

Thanks,
Longfang.
> Thanks,
> Alex
> 
>> +Description:	This debugfs file directory is used for debugging
>> +		of vfio devices that support live migration.
>> +		Each device that supports live migration can create a device
>> +		subdirectory under this directory by referencing the public
>> +		registration interface.
>> +
>> +What:		/sys/kernel/debug/vfio/<bdf>/migration_state
>> +Date:		Feb 2023
>> +KernelVersion:  6.2
>> +Contact:	linux-kernel@vger.kernel.org
>> +Description:	Read the live migration status of the vfio device.
>> +		The status of these live migrations includes:
>> +		ERROR, RUNNING, STOP, STOP_COPY, RESUMING.
> 
> .
> 

Re: [PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

[liulongfang]

On 2023/3/11 7:40, Alex Williamson wrote:
> On Fri, 17 Feb 2023 16:48:29 +0800
> Longfang Liu <liulongfang@huawei.com> wrote:
> 
>> On the debugfs framework of VFIO, if the CONFIG_DEBUG_FS macro is
>> enabled, the debug function is registered for the live migration driver
>> of the HiSilicon accelerator device.
>>
>> On the basis of the original public debug function, a private debug
>> function is added:
>>
>> mig_data file: used to get the migration data of the live migration device
>> mig_attr file: used to get device attributes of the live migration device
>> debug file: used to test for acquiring and writing device state data
>> for VF device.
>>
>> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
>> ---
>>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 282 ++++++++++++++++++
>>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h    |  11 +
>>  2 files changed, 293 insertions(+)
>>
>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> index a1589947e721..a0ecb1cd5707 100644
>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> @@ -15,6 +15,7 @@
>>  #include <linux/anon_inodes.h>
>>  
>>  #include "hisi_acc_vfio_pci.h"
>> +#include "../../vfio.h"
>>  
>>  /* Return 0 on VM acc device ready, -ETIMEDOUT hardware timeout */
>>  static int qm_wait_dev_not_ready(struct hisi_qm *qm)
>> @@ -606,6 +607,18 @@ hisi_acc_check_int_state(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>  	}
>>  }
>>  
>> +static void hisi_acc_vf_migf_save(struct hisi_acc_vf_migration_file *src_migf,
>> +	struct hisi_acc_vf_migration_file *dst_migf)
>> +{
>> +	if (!dst_migf)
>> +		return;
>> +
>> +	dst_migf->disabled = false;
>> +	dst_migf->total_length = src_migf->total_length;
>> +	memcpy(&dst_migf->vf_data, &src_migf->vf_data,
>> +		    sizeof(struct acc_vf_data));
>> +}
>> +
>>  static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
>>  {
>>  	mutex_lock(&migf->lock);
>> @@ -618,12 +631,16 @@ static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
>>  static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>  {
>>  	if (hisi_acc_vdev->resuming_migf) {
>> +		hisi_acc_vf_migf_save(hisi_acc_vdev->resuming_migf,
>> +						hisi_acc_vdev->debug_migf);
>>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->resuming_migf);
>>  		fput(hisi_acc_vdev->resuming_migf->filp);
>>  		hisi_acc_vdev->resuming_migf = NULL;
>>  	}
>>  
>>  	if (hisi_acc_vdev->saving_migf) {
>> +		hisi_acc_vf_migf_save(hisi_acc_vdev->saving_migf,
>> +						hisi_acc_vdev->debug_migf);
>>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->saving_migf);
>>  		fput(hisi_acc_vdev->saving_migf->filp);
>>  		hisi_acc_vdev->saving_migf = NULL;
>> @@ -1303,6 +1320,265 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
>>  	return vfio_pci_core_ioctl(core_vdev, cmd, arg);
>>  }
>>  
>> +static int hisi_acc_vf_debug_io(struct vfio_device *vdev)
>> +{
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>> +	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
>> +	struct device *dev = vdev->dev;
>> +	u64 data;
>> +	int ret;
>> +
>> +	ret = qm_wait_dev_not_ready(vf_qm);
>> +	if (ret)
>> +		dev_err(dev, "VF device not ready!\n");
>> +
>> +	data = readl(vf_qm->io_base + QM_MB_CMD_SEND_BASE);
>> +	dev_info(dev, "debug mailbox val: 0x%llx\n", data);
>> +
>> +	return ret;
>> +}
>> +
>> +static int hisi_acc_vf_debug_resume(struct vfio_device *vdev)
>> +{
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
>> +	struct device *dev = vdev->dev;
>> +	int ret;
>> +
>> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
>> +	if (ret) {
>> +		dev_err(dev, "failed to save device data!\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	ret = vf_qm_check_match(hisi_acc_vdev, migf);
>> +	if (ret) {
>> +		dev_err(dev, "failed to match the VF!\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	ret = vf_qm_load_data(hisi_acc_vdev, migf);
>> +	if (ret) {
>> +		dev_err(dev, "failed to recover the VF!\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	vf_qm_fun_reset(&hisi_acc_vdev->vf_qm);
>> +	dev_info(dev, "successful to resume device data!\n");
>> +
>> +	return 0;
>> +}
>> +
>> +static int hisi_acc_vf_debug_save(struct vfio_device *vdev)
>> +{
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
>> +	struct device *dev = vdev->dev;
>> +	int ret;
>> +
>> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
>> +	if (ret) {
>> +		dev_err(dev, "failed to save device data!\n");
>> +		return -EINVAL;
>> +	}
>> +	dev_info(dev, "successful to save device data!\n");
>> +
>> +	return 0;
>> +}
>> +
>> +static int
>> +hisi_acc_vf_debug_operate(struct vfio_device *vdev, unsigned int cmd)
>> +{
>> +	int ret;
>> +
>> +	switch (cmd) {
>> +	case STATE_SAVE:
>> +		ret = hisi_acc_vf_debug_save(vdev);
>> +		if (ret)
>> +			return ret;
>> +		break;
>> +	case STATE_RESUME:
>> +		ret = hisi_acc_vf_debug_resume(vdev);
>> +		if (ret)
>> +			return ret;
>> +		break;
>> +	case RW_IO_TEST:
>> +		ret = hisi_acc_vf_debug_io(vdev);
>> +		if (ret)
>> +			return ret;
>> +		break;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int hisi_acc_vf_debug_check(struct vfio_device *vdev)
>> +{
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
>> +	enum vfio_device_mig_state state;
>> +
>> +	if (!vdev->mig_ops || !migf) {
>> +		dev_err(vdev->dev, "device not support debugfs!\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	/* If device not opened, the debugfs operation will trigger calltrace */
>> +	(void)vdev->mig_ops->migration_get_state(vdev, &state);
>> +	if (state == VFIO_DEVICE_STATE_ERROR ||
>> +	    state == VFIO_DEVICE_STATE_STOP) {
>> +		dev_err(vdev->dev, "device not opened!\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static ssize_t hisi_acc_vf_debug_write(struct file *filp, const char __user *buffer,
>> +			    size_t count, loff_t *pos)
>> +{
>> +	struct vfio_device	*vdev = filp->private_data;
>> +	char tbuf[VFIO_DEV_DBG_LEN];
>> +	unsigned long cmd;
>> +	int len, ret;
>> +
>> +	if (*pos)
>> +		return 0;
>> +
>> +	if (count >= VFIO_DEV_DBG_LEN)
>> +		return -ENOSPC;
>> +
>> +	ret = hisi_acc_vf_debug_check(vdev);
>> +	if (ret)
>> +		return -EINVAL;
>> +
>> +	len = simple_write_to_buffer(tbuf, VFIO_DEV_DBG_LEN - 1,
>> +					pos, buffer, count);
>> +	if (len < 0 || len > VFIO_DEV_DBG_LEN - 1)
>> +		return -EINVAL;
>> +	tbuf[len] = '\0';
>> +	if (kstrtoul(tbuf, 0, &cmd))
>> +		return -EFAULT;
>> +
>> +	ret = hisi_acc_vf_debug_operate(vdev, cmd);
>> +	if (ret) {
>> +		dev_err(vdev->dev, "device debug test failed!\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	return count;
>> +}
>> +
>> +static const struct file_operations hisi_acc_vf_debug_fops = {
>> +	.owner = THIS_MODULE,
>> +	.open = simple_open,
>> +	.write = hisi_acc_vf_debug_write,
>> +};
>> +
>> +static void seq_print_hex_data(struct seq_file *seq, const void *buf, size_t len)
>> +{
>> +#define HEX_LINE_SIZE		131
>> +#define HEX_ROW_SIZE		16
>> +	unsigned char linebuf[HEX_LINE_SIZE];
>> +	int i, linelen, remaining = len;
>> +	const u8 *ptr = buf;
>> +
>> +	for (i = 0; i < len; i += HEX_ROW_SIZE) {
>> +		linelen = min(remaining, HEX_ROW_SIZE);
>> +		remaining -= HEX_ROW_SIZE;
>> +
>> +		hex_dump_to_buffer(ptr + i, linelen, HEX_ROW_SIZE, 1,
>> +					linebuf, sizeof(linebuf), false);
>> +
>> +		seq_printf(seq, "%s%.8x: %s\n", "Mig Data:", i, linebuf);
>> +	}
>> +}
>> +
>> +static int hisi_acc_vf_data_read(struct seq_file *seq, void *data)
>> +{
>> +	struct device *vf_dev = seq->private;
>> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
>> +	struct vfio_device	*vdev = &core_device->vdev;
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
>> +	size_t vf_data_sz = offsetofend(struct acc_vf_data, padding);
>> +
>> +	if (debug_migf && debug_migf->total_length)
>> +		seq_print_hex_data(seq, (unsigned char *)&debug_migf->vf_data,
>> +				vf_data_sz);
>> +	else
>> +		seq_printf(seq, "%s\n", "device not migrated!");
>> +
>> +	return 0;
>> +}
>> +
>> +static int hisi_acc_vf_attr_read(struct seq_file *seq, void *data)
>> +{
>> +	struct device *vf_dev = seq->private;
>> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
>> +	struct vfio_device	*vdev = &core_device->vdev;
>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
>> +
>> +	if (debug_migf && debug_migf->total_length) {
>> +		seq_printf(seq,
>> +			 "acc device:\n"
>> +			 "device  state: %d\n"
>> +			 "device  ready: %u\n"
>> +			 "data    valid: %d\n"
>> +			 "data     size: %lu\n",
>> +			 hisi_acc_vdev->mig_state,
>> +			 hisi_acc_vdev->vf_qm_state,
>> +			 debug_migf->disabled,
>> +			 debug_migf->total_length);
>> +	} else {
>> +		seq_printf(seq, "%s\n", "device not migrated!");
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>> +{
>> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
>> +	struct device *dev = vdev->dev;
>> +	void *migf = NULL;
>> +
>> +	if (!debugfs_initialized())
>> +		return 0;
>> +
>> +	vfio_vf_debugfs_init(vdev);
>> +
>> +	migf = kzalloc(sizeof(struct hisi_acc_vf_migration_file), GFP_KERNEL);
>> +	if (!migf)
>> +		return -ENOMEM;
>> +
>> +	hisi_acc_vdev->debug_migf = migf;
>> +
>> +	debugfs_create_devm_seqfile(dev, "migration_data", vdev->debug_root,
>> +				  hisi_acc_vf_data_read);
>> +	debugfs_create_devm_seqfile(dev, "migration_attr", vdev->debug_root,
>> +				  hisi_acc_vf_attr_read);
>> +
>> +	debugfs_create_file("migration_debug", 0200, vdev->debug_root,
>> +				  vdev, &hisi_acc_vf_debug_fops);
>> +
> 
> All of these are going to be device specific, right?  So do we really
> want a debugfs file structure that looks like:
> 
> vfio
> └── migration
>     ├── hisi_acc
>     │   ├── attr
>     │   ├── data
>     │   └── debug
>     └── state
> 

According to this directory structure, I also need to change.

Thanks
Longfang.
> Thanks,
> Alex
> 
>> +	return 0;
>> +}
>> +
>> +static void hisi_acc_vf_debugfs_exit(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>> +{
>> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
>> +
>> +	if (!debugfs_initialized())
>> +		return;
>> +
>> +	vfio_vf_debugfs_exit(vdev);
>> +	kfree(hisi_acc_vdev->debug_migf);
>> +}
>> +
>>  static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
>>  {
>>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
>> @@ -1416,6 +1692,9 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>>  	if (IS_ERR(hisi_acc_vdev))
>>  		return PTR_ERR(hisi_acc_vdev);
>>  
>> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
>> +		hisi_acc_vfio_debug_init(hisi_acc_vdev);
>> +
>>  	dev_set_drvdata(&pdev->dev, &hisi_acc_vdev->core_device);
>>  	ret = vfio_pci_core_register_device(&hisi_acc_vdev->core_device);
>>  	if (ret)
>> @@ -1423,6 +1702,8 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>>  	return 0;
>>  
>>  out_put_vdev:
>> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
>> +		hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
>>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
>>  	return ret;
>>  }
>> @@ -1431,6 +1712,7 @@ static void hisi_acc_vfio_pci_remove(struct pci_dev *pdev)
>>  {
>>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_drvdata(pdev);
>>  
>> +	hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
>>  	vfio_pci_core_unregister_device(&hisi_acc_vdev->core_device);
>>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
>>  }
>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
>> index dcabfeec6ca1..ef50b12f018d 100644
>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
>> @@ -49,6 +49,14 @@
>>  #define QM_EQC_DW0		0X8000
>>  #define QM_AEQC_DW0		0X8020
>>  
>> +#define VFIO_DEV_DBG_LEN		256
>> +
>> +enum mig_debug_cmd {
>> +	STATE_SAVE,
>> +	STATE_RESUME,
>> +	RW_IO_TEST,
>> +};
>> +
>>  struct acc_vf_data {
>>  #define QM_MATCH_SIZE offsetofend(struct acc_vf_data, qm_rsv_state)
>>  	/* QM match information */
>> @@ -113,5 +121,8 @@ struct hisi_acc_vf_core_device {
>>  	spinlock_t reset_lock;
>>  	struct hisi_acc_vf_migration_file *resuming_migf;
>>  	struct hisi_acc_vf_migration_file *saving_migf;
>> +
>> +	/* For debugfs */
>> +	struct hisi_acc_vf_migration_file *debug_migf;
>>  };
>>  #endif /* HISI_ACC_VFIO_PCI_H */
> 
> .
> 

Re: [PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

[liulongfang]

On 2023/3/14 19:04, liulongfang wrote:
> On 2023/3/11 7:40, Alex Williamson wrote:
>> On Fri, 17 Feb 2023 16:48:29 +0800
>> Longfang Liu <liulongfang@huawei.com> wrote:
>>
>>> On the debugfs framework of VFIO, if the CONFIG_DEBUG_FS macro is
>>> enabled, the debug function is registered for the live migration driver
>>> of the HiSilicon accelerator device.
>>>
>>> On the basis of the original public debug function, a private debug
>>> function is added:
>>>
>>> mig_data file: used to get the migration data of the live migration device
>>> mig_attr file: used to get device attributes of the live migration device
>>> debug file: used to test for acquiring and writing device state data
>>> for VF device.
>>>
>>> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
>>> ---
>>>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 282 ++++++++++++++++++
>>>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h    |  11 +
>>>  2 files changed, 293 insertions(+)
>>>
>>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>>> index a1589947e721..a0ecb1cd5707 100644
>>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>>> @@ -15,6 +15,7 @@
>>>  #include <linux/anon_inodes.h>
>>>  
>>>  #include "hisi_acc_vfio_pci.h"
>>> +#include "../../vfio.h"
>>>  
>>>  /* Return 0 on VM acc device ready, -ETIMEDOUT hardware timeout */
>>>  static int qm_wait_dev_not_ready(struct hisi_qm *qm)
>>> @@ -606,6 +607,18 @@ hisi_acc_check_int_state(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>>  	}
>>>  }
>>>  
>>> +static void hisi_acc_vf_migf_save(struct hisi_acc_vf_migration_file *src_migf,
>>> +	struct hisi_acc_vf_migration_file *dst_migf)
>>> +{
>>> +	if (!dst_migf)
>>> +		return;
>>> +
>>> +	dst_migf->disabled = false;
>>> +	dst_migf->total_length = src_migf->total_length;
>>> +	memcpy(&dst_migf->vf_data, &src_migf->vf_data,
>>> +		    sizeof(struct acc_vf_data));
>>> +}
>>> +
>>>  static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
>>>  {
>>>  	mutex_lock(&migf->lock);
>>> @@ -618,12 +631,16 @@ static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
>>>  static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>>  {
>>>  	if (hisi_acc_vdev->resuming_migf) {
>>> +		hisi_acc_vf_migf_save(hisi_acc_vdev->resuming_migf,
>>> +						hisi_acc_vdev->debug_migf);
>>>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->resuming_migf);
>>>  		fput(hisi_acc_vdev->resuming_migf->filp);
>>>  		hisi_acc_vdev->resuming_migf = NULL;
>>>  	}
>>>  
>>>  	if (hisi_acc_vdev->saving_migf) {
>>> +		hisi_acc_vf_migf_save(hisi_acc_vdev->saving_migf,
>>> +						hisi_acc_vdev->debug_migf);
>>>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->saving_migf);
>>>  		fput(hisi_acc_vdev->saving_migf->filp);
>>>  		hisi_acc_vdev->saving_migf = NULL;
>>> @@ -1303,6 +1320,265 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
>>>  	return vfio_pci_core_ioctl(core_vdev, cmd, arg);
>>>  }
>>>  
>>> +static int hisi_acc_vf_debug_io(struct vfio_device *vdev)
>>> +{
>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>> +	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
>>> +	struct device *dev = vdev->dev;
>>> +	u64 data;
>>> +	int ret;
>>> +
>>> +	ret = qm_wait_dev_not_ready(vf_qm);
>>> +	if (ret)
>>> +		dev_err(dev, "VF device not ready!\n");
>>> +
>>> +	data = readl(vf_qm->io_base + QM_MB_CMD_SEND_BASE);
>>> +	dev_info(dev, "debug mailbox val: 0x%llx\n", data);
>>> +
>>> +	return ret;
>>> +}
>>> +
>>> +static int hisi_acc_vf_debug_resume(struct vfio_device *vdev)
>>> +{
>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
>>> +	struct device *dev = vdev->dev;
>>> +	int ret;
>>> +
>>> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to save device data!\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	ret = vf_qm_check_match(hisi_acc_vdev, migf);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to match the VF!\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	ret = vf_qm_load_data(hisi_acc_vdev, migf);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to recover the VF!\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	vf_qm_fun_reset(&hisi_acc_vdev->vf_qm);
>>> +	dev_info(dev, "successful to resume device data!\n");
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int hisi_acc_vf_debug_save(struct vfio_device *vdev)
>>> +{
>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
>>> +	struct device *dev = vdev->dev;
>>> +	int ret;
>>> +
>>> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to save device data!\n");
>>> +		return -EINVAL;
>>> +	}
>>> +	dev_info(dev, "successful to save device data!\n");
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int
>>> +hisi_acc_vf_debug_operate(struct vfio_device *vdev, unsigned int cmd)
>>> +{
>>> +	int ret;
>>> +
>>> +	switch (cmd) {
>>> +	case STATE_SAVE:
>>> +		ret = hisi_acc_vf_debug_save(vdev);
>>> +		if (ret)
>>> +			return ret;
>>> +		break;
>>> +	case STATE_RESUME:
>>> +		ret = hisi_acc_vf_debug_resume(vdev);
>>> +		if (ret)
>>> +			return ret;
>>> +		break;
>>> +	case RW_IO_TEST:
>>> +		ret = hisi_acc_vf_debug_io(vdev);
>>> +		if (ret)
>>> +			return ret;
>>> +		break;
>>> +	default:
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int hisi_acc_vf_debug_check(struct vfio_device *vdev)
>>> +{
>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
>>> +	enum vfio_device_mig_state state;
>>> +
>>> +	if (!vdev->mig_ops || !migf) {
>>> +		dev_err(vdev->dev, "device not support debugfs!\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	/* If device not opened, the debugfs operation will trigger calltrace */
>>> +	(void)vdev->mig_ops->migration_get_state(vdev, &state);
>>> +	if (state == VFIO_DEVICE_STATE_ERROR ||
>>> +	    state == VFIO_DEVICE_STATE_STOP) {
>>> +		dev_err(vdev->dev, "device not opened!\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static ssize_t hisi_acc_vf_debug_write(struct file *filp, const char __user *buffer,
>>> +			    size_t count, loff_t *pos)
>>> +{
>>> +	struct vfio_device	*vdev = filp->private_data;
>>> +	char tbuf[VFIO_DEV_DBG_LEN];
>>> +	unsigned long cmd;
>>> +	int len, ret;
>>> +
>>> +	if (*pos)
>>> +		return 0;
>>> +
>>> +	if (count >= VFIO_DEV_DBG_LEN)
>>> +		return -ENOSPC;
>>> +
>>> +	ret = hisi_acc_vf_debug_check(vdev);
>>> +	if (ret)
>>> +		return -EINVAL;
>>> +
>>> +	len = simple_write_to_buffer(tbuf, VFIO_DEV_DBG_LEN - 1,
>>> +					pos, buffer, count);
>>> +	if (len < 0 || len > VFIO_DEV_DBG_LEN - 1)
>>> +		return -EINVAL;
>>> +	tbuf[len] = '\0';
>>> +	if (kstrtoul(tbuf, 0, &cmd))
>>> +		return -EFAULT;
>>> +
>>> +	ret = hisi_acc_vf_debug_operate(vdev, cmd);
>>> +	if (ret) {
>>> +		dev_err(vdev->dev, "device debug test failed!\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	return count;
>>> +}
>>> +
>>> +static const struct file_operations hisi_acc_vf_debug_fops = {
>>> +	.owner = THIS_MODULE,
>>> +	.open = simple_open,
>>> +	.write = hisi_acc_vf_debug_write,
>>> +};
>>> +
>>> +static void seq_print_hex_data(struct seq_file *seq, const void *buf, size_t len)
>>> +{
>>> +#define HEX_LINE_SIZE		131
>>> +#define HEX_ROW_SIZE		16
>>> +	unsigned char linebuf[HEX_LINE_SIZE];
>>> +	int i, linelen, remaining = len;
>>> +	const u8 *ptr = buf;
>>> +
>>> +	for (i = 0; i < len; i += HEX_ROW_SIZE) {
>>> +		linelen = min(remaining, HEX_ROW_SIZE);
>>> +		remaining -= HEX_ROW_SIZE;
>>> +
>>> +		hex_dump_to_buffer(ptr + i, linelen, HEX_ROW_SIZE, 1,
>>> +					linebuf, sizeof(linebuf), false);
>>> +
>>> +		seq_printf(seq, "%s%.8x: %s\n", "Mig Data:", i, linebuf);
>>> +	}
>>> +}
>>> +
>>> +static int hisi_acc_vf_data_read(struct seq_file *seq, void *data)
>>> +{
>>> +	struct device *vf_dev = seq->private;
>>> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
>>> +	struct vfio_device	*vdev = &core_device->vdev;
>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
>>> +	size_t vf_data_sz = offsetofend(struct acc_vf_data, padding);
>>> +
>>> +	if (debug_migf && debug_migf->total_length)
>>> +		seq_print_hex_data(seq, (unsigned char *)&debug_migf->vf_data,
>>> +				vf_data_sz);
>>> +	else
>>> +		seq_printf(seq, "%s\n", "device not migrated!");
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int hisi_acc_vf_attr_read(struct seq_file *seq, void *data)
>>> +{
>>> +	struct device *vf_dev = seq->private;
>>> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
>>> +	struct vfio_device	*vdev = &core_device->vdev;
>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
>>> +
>>> +	if (debug_migf && debug_migf->total_length) {
>>> +		seq_printf(seq,
>>> +			 "acc device:\n"
>>> +			 "device  state: %d\n"
>>> +			 "device  ready: %u\n"
>>> +			 "data    valid: %d\n"
>>> +			 "data     size: %lu\n",
>>> +			 hisi_acc_vdev->mig_state,
>>> +			 hisi_acc_vdev->vf_qm_state,
>>> +			 debug_migf->disabled,
>>> +			 debug_migf->total_length);
>>> +	} else {
>>> +		seq_printf(seq, "%s\n", "device not migrated!");
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>> +{
>>> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
>>> +	struct device *dev = vdev->dev;
>>> +	void *migf = NULL;
>>> +
>>> +	if (!debugfs_initialized())
>>> +		return 0;
>>> +
>>> +	vfio_vf_debugfs_init(vdev);
>>> +
>>> +	migf = kzalloc(sizeof(struct hisi_acc_vf_migration_file), GFP_KERNEL);
>>> +	if (!migf)
>>> +		return -ENOMEM;
>>> +
>>> +	hisi_acc_vdev->debug_migf = migf;
>>> +
>>> +	debugfs_create_devm_seqfile(dev, "migration_data", vdev->debug_root,
>>> +				  hisi_acc_vf_data_read);
>>> +	debugfs_create_devm_seqfile(dev, "migration_attr", vdev->debug_root,
>>> +				  hisi_acc_vf_attr_read);
>>> +
>>> +	debugfs_create_file("migration_debug", 0200, vdev->debug_root,
>>> +				  vdev, &hisi_acc_vf_debug_fops);
>>> +
>>
>> All of these are going to be device specific, right?  So do we really
>> want a debugfs file structure that looks like:
>>
>> vfio
>> └── migration
>>     ├── hisi_acc
>>     │   ├── attr
>>     │   ├── data
>>     │   └── debug
>>     └── state
>>
> 
> According to this directory structure, I also need to change.
> 
> Thanks
> Longfang.

If there are multiple devices participating in live migration, their current directory structure
is like this:
vfio
├── hisi_acc_1
│     ├── attr
│     ├── data
│     ├── debug
│     └── state
│
└── hisi_acc_2
       ├── attr
       ├── data
       ├── debug
       └── state


If you want to change to the above directory structure, which directory should the
‘state’ file be placed in the case of multiple devices?
vfio
 └─ migration
     ├── hisi_acc
     │     ├── attr
     │     ├── data
     │     └── debug
     └── state

Like this or other directory structure?
vfio
└─ migration
    ├── hisi_acc_1
    │     ├── attr
    │     ├── data
    │     └── debug
    ├── hisi_acc_2
    │     ├── attr
    │     ├── data
    │     └── debug
    └── state
	   ├── hisi_acc_1
	   └── hisi_acc_2

Thanks，
Longfang.

>> Thanks,
>> Alex
>>
>>> +	return 0;
>>> +}
>>> +
>>> +static void hisi_acc_vf_debugfs_exit(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>> +{
>>> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
>>> +
>>> +	if (!debugfs_initialized())
>>> +		return;
>>> +
>>> +	vfio_vf_debugfs_exit(vdev);
>>> +	kfree(hisi_acc_vdev->debug_migf);
>>> +}
>>> +
>>>  static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
>>>  {
>>>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
>>> @@ -1416,6 +1692,9 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>>>  	if (IS_ERR(hisi_acc_vdev))
>>>  		return PTR_ERR(hisi_acc_vdev);
>>>  
>>> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
>>> +		hisi_acc_vfio_debug_init(hisi_acc_vdev);
>>> +
>>>  	dev_set_drvdata(&pdev->dev, &hisi_acc_vdev->core_device);
>>>  	ret = vfio_pci_core_register_device(&hisi_acc_vdev->core_device);
>>>  	if (ret)
>>> @@ -1423,6 +1702,8 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>>>  	return 0;
>>>  
>>>  out_put_vdev:
>>> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
>>> +		hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
>>>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
>>>  	return ret;
>>>  }
>>> @@ -1431,6 +1712,7 @@ static void hisi_acc_vfio_pci_remove(struct pci_dev *pdev)
>>>  {
>>>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_drvdata(pdev);
>>>  
>>> +	hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
>>>  	vfio_pci_core_unregister_device(&hisi_acc_vdev->core_device);
>>>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
>>>  }
>>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
>>> index dcabfeec6ca1..ef50b12f018d 100644
>>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
>>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
>>> @@ -49,6 +49,14 @@
>>>  #define QM_EQC_DW0		0X8000
>>>  #define QM_AEQC_DW0		0X8020
>>>  
>>> +#define VFIO_DEV_DBG_LEN		256
>>> +
>>> +enum mig_debug_cmd {
>>> +	STATE_SAVE,
>>> +	STATE_RESUME,
>>> +	RW_IO_TEST,
>>> +};
>>> +
>>>  struct acc_vf_data {
>>>  #define QM_MATCH_SIZE offsetofend(struct acc_vf_data, qm_rsv_state)
>>>  	/* QM match information */
>>> @@ -113,5 +121,8 @@ struct hisi_acc_vf_core_device {
>>>  	spinlock_t reset_lock;
>>>  	struct hisi_acc_vf_migration_file *resuming_migf;
>>>  	struct hisi_acc_vf_migration_file *saving_migf;
>>> +
>>> +	/* For debugfs */
>>> +	struct hisi_acc_vf_migration_file *debug_migf;
>>>  };
>>>  #endif /* HISI_ACC_VFIO_PCI_H */
>>
>> .
>>

Re: [PATCH v8 1/5] vfio/migration: Add debugfs to live migration driver

[liulongfang]

On 2023/3/14 17:32, liulongfang wrote:
> On 2023/3/11 1:12, Jason Gunthorpe wrote:
>> On Fri, Feb 17, 2023 at 04:48:27PM +0800, Longfang Liu wrote:
>>> +void vfio_vf_debugfs_init(struct vfio_device *vdev)
>>> +{
>>> +	struct device *dev = &vdev->device;
>>> +
>>> +	vdev->debug_root = debugfs_create_dir(dev_name(vdev->dev), vfio_debugfs_root);
>>> +
>>> +	debugfs_create_devm_seqfile(dev, "migration_state", vdev->debug_root,
>>> +				  vfio_vf_state_read);
>>> +}
>>> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_init);
>>> +
>>> +void vfio_vf_debugfs_exit(struct vfio_device *vdev)
>>> +{
>>> +	debugfs_remove_recursive(vdev->debug_root);
>>> +}
>>> +EXPORT_SYMBOL_GPL(vfio_vf_debugfs_exit);
>>> +
>>> +void  vfio_debugfs_create_root(void)
>>> +{
>>> +	vfio_debugfs_root = debugfs_create_dir("vfio", NULL);
>>> +}
>>> +EXPORT_SYMBOL_GPL(vfio_debugfs_create_root);
>>> +
>>> +void  vfio_debugfs_remove_root(void)
>>> +{
>>> +	debugfs_remove_recursive(vfio_debugfs_root);
>>> +	vfio_debugfs_root = NULL;
>>> +}
>>> +EXPORT_SYMBOL_GPL(vfio_debugfs_remove_root);
>>
>> Why are these symbols exported?
>>
> 
> If the export statement is not added, a compilation error will occur:
> 
> ERROR: modpost: "vfio_vf_debugfs_init" [drivers/vfio/pci/hisilicon/hisi-acc-vfio-pci.ko] undefined!
> ERROR: modpost: "vfio_vf_debugfs_exit" [drivers/vfio/pci/hisilicon/hisi-acc-vfio-pci.ko] undefined!
> scripts/Makefile.modpost:126: recipe for target 'Module.symvers' failed
> make[1]: *** [Module.symvers] Error 1
> 

The first two functions cannot remove the export statement,
but the latter two can be removed.

Thanks,
Longfang.
> 
>> Jason
>>
>> .
> Thanks,
> Longfang
> 
>>

Re: [PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

[Alex Williamson]

On Tue, 14 Mar 2023 19:21:29 +0800
liulongfang <liulongfang@huawei.com> wrote:

> On 2023/3/14 19:04, liulongfang wrote:
> > On 2023/3/11 7:40, Alex Williamson wrote:  
> >> On Fri, 17 Feb 2023 16:48:29 +0800
> >> Longfang Liu <liulongfang@huawei.com> wrote:
> >>  
> >>> On the debugfs framework of VFIO, if the CONFIG_DEBUG_FS macro is
> >>> enabled, the debug function is registered for the live migration driver
> >>> of the HiSilicon accelerator device.
> >>>
> >>> On the basis of the original public debug function, a private debug
> >>> function is added:
> >>>
> >>> mig_data file: used to get the migration data of the live migration device
> >>> mig_attr file: used to get device attributes of the live migration device
> >>> debug file: used to test for acquiring and writing device state data
> >>> for VF device.
> >>>
> >>> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
> >>> ---
> >>>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 282 ++++++++++++++++++
> >>>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h    |  11 +
> >>>  2 files changed, 293 insertions(+)
> >>>
> >>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> >>> index a1589947e721..a0ecb1cd5707 100644
> >>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> >>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> >>> @@ -15,6 +15,7 @@
> >>>  #include <linux/anon_inodes.h>
> >>>  
> >>>  #include "hisi_acc_vfio_pci.h"
> >>> +#include "../../vfio.h"
> >>>  
> >>>  /* Return 0 on VM acc device ready, -ETIMEDOUT hardware timeout */
> >>>  static int qm_wait_dev_not_ready(struct hisi_qm *qm)
> >>> @@ -606,6 +607,18 @@ hisi_acc_check_int_state(struct hisi_acc_vf_core_device *hisi_acc_vdev)
> >>>  	}
> >>>  }
> >>>  
> >>> +static void hisi_acc_vf_migf_save(struct hisi_acc_vf_migration_file *src_migf,
> >>> +	struct hisi_acc_vf_migration_file *dst_migf)
> >>> +{
> >>> +	if (!dst_migf)
> >>> +		return;
> >>> +
> >>> +	dst_migf->disabled = false;
> >>> +	dst_migf->total_length = src_migf->total_length;
> >>> +	memcpy(&dst_migf->vf_data, &src_migf->vf_data,
> >>> +		    sizeof(struct acc_vf_data));
> >>> +}
> >>> +
> >>>  static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
> >>>  {
> >>>  	mutex_lock(&migf->lock);
> >>> @@ -618,12 +631,16 @@ static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
> >>>  static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vdev)
> >>>  {
> >>>  	if (hisi_acc_vdev->resuming_migf) {
> >>> +		hisi_acc_vf_migf_save(hisi_acc_vdev->resuming_migf,
> >>> +						hisi_acc_vdev->debug_migf);
> >>>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->resuming_migf);
> >>>  		fput(hisi_acc_vdev->resuming_migf->filp);
> >>>  		hisi_acc_vdev->resuming_migf = NULL;
> >>>  	}
> >>>  
> >>>  	if (hisi_acc_vdev->saving_migf) {
> >>> +		hisi_acc_vf_migf_save(hisi_acc_vdev->saving_migf,
> >>> +						hisi_acc_vdev->debug_migf);
> >>>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->saving_migf);
> >>>  		fput(hisi_acc_vdev->saving_migf->filp);
> >>>  		hisi_acc_vdev->saving_migf = NULL;
> >>> @@ -1303,6 +1320,265 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
> >>>  	return vfio_pci_core_ioctl(core_vdev, cmd, arg);
> >>>  }
> >>>  
> >>> +static int hisi_acc_vf_debug_io(struct vfio_device *vdev)
> >>> +{
> >>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> >>> +	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
> >>> +	struct device *dev = vdev->dev;
> >>> +	u64 data;
> >>> +	int ret;
> >>> +
> >>> +	ret = qm_wait_dev_not_ready(vf_qm);
> >>> +	if (ret)
> >>> +		dev_err(dev, "VF device not ready!\n");
> >>> +
> >>> +	data = readl(vf_qm->io_base + QM_MB_CMD_SEND_BASE);
> >>> +	dev_info(dev, "debug mailbox val: 0x%llx\n", data);
> >>> +
> >>> +	return ret;
> >>> +}
> >>> +
> >>> +static int hisi_acc_vf_debug_resume(struct vfio_device *vdev)
> >>> +{
> >>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> >>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
> >>> +	struct device *dev = vdev->dev;
> >>> +	int ret;
> >>> +
> >>> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
> >>> +	if (ret) {
> >>> +		dev_err(dev, "failed to save device data!\n");
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	ret = vf_qm_check_match(hisi_acc_vdev, migf);
> >>> +	if (ret) {
> >>> +		dev_err(dev, "failed to match the VF!\n");
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	ret = vf_qm_load_data(hisi_acc_vdev, migf);
> >>> +	if (ret) {
> >>> +		dev_err(dev, "failed to recover the VF!\n");
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	vf_qm_fun_reset(&hisi_acc_vdev->vf_qm);
> >>> +	dev_info(dev, "successful to resume device data!\n");
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int hisi_acc_vf_debug_save(struct vfio_device *vdev)
> >>> +{
> >>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> >>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
> >>> +	struct device *dev = vdev->dev;
> >>> +	int ret;
> >>> +
> >>> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
> >>> +	if (ret) {
> >>> +		dev_err(dev, "failed to save device data!\n");
> >>> +		return -EINVAL;
> >>> +	}
> >>> +	dev_info(dev, "successful to save device data!\n");
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int
> >>> +hisi_acc_vf_debug_operate(struct vfio_device *vdev, unsigned int cmd)
> >>> +{
> >>> +	int ret;
> >>> +
> >>> +	switch (cmd) {
> >>> +	case STATE_SAVE:
> >>> +		ret = hisi_acc_vf_debug_save(vdev);
> >>> +		if (ret)
> >>> +			return ret;
> >>> +		break;
> >>> +	case STATE_RESUME:
> >>> +		ret = hisi_acc_vf_debug_resume(vdev);
> >>> +		if (ret)
> >>> +			return ret;
> >>> +		break;
> >>> +	case RW_IO_TEST:
> >>> +		ret = hisi_acc_vf_debug_io(vdev);
> >>> +		if (ret)
> >>> +			return ret;
> >>> +		break;
> >>> +	default:
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int hisi_acc_vf_debug_check(struct vfio_device *vdev)
> >>> +{
> >>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> >>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
> >>> +	enum vfio_device_mig_state state;
> >>> +
> >>> +	if (!vdev->mig_ops || !migf) {
> >>> +		dev_err(vdev->dev, "device not support debugfs!\n");
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	/* If device not opened, the debugfs operation will trigger calltrace */
> >>> +	(void)vdev->mig_ops->migration_get_state(vdev, &state);
> >>> +	if (state == VFIO_DEVICE_STATE_ERROR ||
> >>> +	    state == VFIO_DEVICE_STATE_STOP) {
> >>> +		dev_err(vdev->dev, "device not opened!\n");
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static ssize_t hisi_acc_vf_debug_write(struct file *filp, const char __user *buffer,
> >>> +			    size_t count, loff_t *pos)
> >>> +{
> >>> +	struct vfio_device	*vdev = filp->private_data;
> >>> +	char tbuf[VFIO_DEV_DBG_LEN];
> >>> +	unsigned long cmd;
> >>> +	int len, ret;
> >>> +
> >>> +	if (*pos)
> >>> +		return 0;
> >>> +
> >>> +	if (count >= VFIO_DEV_DBG_LEN)
> >>> +		return -ENOSPC;
> >>> +
> >>> +	ret = hisi_acc_vf_debug_check(vdev);
> >>> +	if (ret)
> >>> +		return -EINVAL;
> >>> +
> >>> +	len = simple_write_to_buffer(tbuf, VFIO_DEV_DBG_LEN - 1,
> >>> +					pos, buffer, count);
> >>> +	if (len < 0 || len > VFIO_DEV_DBG_LEN - 1)
> >>> +		return -EINVAL;
> >>> +	tbuf[len] = '\0';
> >>> +	if (kstrtoul(tbuf, 0, &cmd))
> >>> +		return -EFAULT;
> >>> +
> >>> +	ret = hisi_acc_vf_debug_operate(vdev, cmd);
> >>> +	if (ret) {
> >>> +		dev_err(vdev->dev, "device debug test failed!\n");
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	return count;
> >>> +}
> >>> +
> >>> +static const struct file_operations hisi_acc_vf_debug_fops = {
> >>> +	.owner = THIS_MODULE,
> >>> +	.open = simple_open,
> >>> +	.write = hisi_acc_vf_debug_write,
> >>> +};
> >>> +
> >>> +static void seq_print_hex_data(struct seq_file *seq, const void *buf, size_t len)
> >>> +{
> >>> +#define HEX_LINE_SIZE		131
> >>> +#define HEX_ROW_SIZE		16
> >>> +	unsigned char linebuf[HEX_LINE_SIZE];
> >>> +	int i, linelen, remaining = len;
> >>> +	const u8 *ptr = buf;
> >>> +
> >>> +	for (i = 0; i < len; i += HEX_ROW_SIZE) {
> >>> +		linelen = min(remaining, HEX_ROW_SIZE);
> >>> +		remaining -= HEX_ROW_SIZE;
> >>> +
> >>> +		hex_dump_to_buffer(ptr + i, linelen, HEX_ROW_SIZE, 1,
> >>> +					linebuf, sizeof(linebuf), false);
> >>> +
> >>> +		seq_printf(seq, "%s%.8x: %s\n", "Mig Data:", i, linebuf);
> >>> +	}
> >>> +}
> >>> +
> >>> +static int hisi_acc_vf_data_read(struct seq_file *seq, void *data)
> >>> +{
> >>> +	struct device *vf_dev = seq->private;
> >>> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
> >>> +	struct vfio_device	*vdev = &core_device->vdev;
> >>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> >>> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
> >>> +	size_t vf_data_sz = offsetofend(struct acc_vf_data, padding);
> >>> +
> >>> +	if (debug_migf && debug_migf->total_length)
> >>> +		seq_print_hex_data(seq, (unsigned char *)&debug_migf->vf_data,
> >>> +				vf_data_sz);
> >>> +	else
> >>> +		seq_printf(seq, "%s\n", "device not migrated!");
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int hisi_acc_vf_attr_read(struct seq_file *seq, void *data)
> >>> +{
> >>> +	struct device *vf_dev = seq->private;
> >>> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
> >>> +	struct vfio_device	*vdev = &core_device->vdev;
> >>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
> >>> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
> >>> +
> >>> +	if (debug_migf && debug_migf->total_length) {
> >>> +		seq_printf(seq,
> >>> +			 "acc device:\n"
> >>> +			 "device  state: %d\n"
> >>> +			 "device  ready: %u\n"
> >>> +			 "data    valid: %d\n"
> >>> +			 "data     size: %lu\n",
> >>> +			 hisi_acc_vdev->mig_state,
> >>> +			 hisi_acc_vdev->vf_qm_state,
> >>> +			 debug_migf->disabled,
> >>> +			 debug_migf->total_length);
> >>> +	} else {
> >>> +		seq_printf(seq, "%s\n", "device not migrated!");
> >>> +	}
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vdev)
> >>> +{
> >>> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
> >>> +	struct device *dev = vdev->dev;
> >>> +	void *migf = NULL;
> >>> +
> >>> +	if (!debugfs_initialized())
> >>> +		return 0;
> >>> +
> >>> +	vfio_vf_debugfs_init(vdev);
> >>> +
> >>> +	migf = kzalloc(sizeof(struct hisi_acc_vf_migration_file), GFP_KERNEL);
> >>> +	if (!migf)
> >>> +		return -ENOMEM;
> >>> +
> >>> +	hisi_acc_vdev->debug_migf = migf;
> >>> +
> >>> +	debugfs_create_devm_seqfile(dev, "migration_data", vdev->debug_root,
> >>> +				  hisi_acc_vf_data_read);
> >>> +	debugfs_create_devm_seqfile(dev, "migration_attr", vdev->debug_root,
> >>> +				  hisi_acc_vf_attr_read);
> >>> +
> >>> +	debugfs_create_file("migration_debug", 0200, vdev->debug_root,
> >>> +				  vdev, &hisi_acc_vf_debug_fops);
> >>> +  
> >>
> >> All of these are going to be device specific, right?  So do we really
> >> want a debugfs file structure that looks like:
> >>
> >> vfio
> >> └── migration
> >>     ├── hisi_acc
> >>     │   ├── attr
> >>     │   ├── data
> >>     │   └── debug
> >>     └── state
> >>  
> > 
> > According to this directory structure, I also need to change.
> > 
> > Thanks
> > Longfang.  
> 
> If there are multiple devices participating in live migration, their current directory structure
> is like this:
> vfio
> ├── hisi_acc_1
> │     ├── attr
> │     ├── data
> │     ├── debug
> │     └── state
> │
> └── hisi_acc_2
>        ├── attr
>        ├── data
>        ├── debug
>        └── state
> 
> 
> If you want to change to the above directory structure, which directory should the
> ‘state’ file be placed in the case of multiple devices?
> vfio
>  └─ migration
>      ├── hisi_acc
>      │     ├── attr
>      │     ├── data
>      │     └── debug
>      └── state
> 
> Like this or other directory structure?
> vfio
> └─ migration
>     ├── hisi_acc_1
>     │     ├── attr
>     │     ├── data
>     │     └── debug
>     ├── hisi_acc_2
>     │     ├── attr
>     │     ├── data
>     │     └── debug
>     └── state
> 	   ├── hisi_acc_1
> 	   └── hisi_acc_2> 

I was thinking:

vfio
├── <name1>
│   └── migration
│       ├── hisi_acc
│       │   ├── attr
│       │   ├── data
│       │   └── debug
│       └── state
└── <name2>
    └── migration
        ├── hisi_acc
        │   ├── attr
        │   ├── data
        │   └── debug
        └── state

My concern is that if {attr,data,debug} have driver specific
definitions, they should have their own driver specific namespace.
Thanks,

Alex

 
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static void hisi_acc_vf_debugfs_exit(struct hisi_acc_vf_core_device *hisi_acc_vdev)
> >>> +{
> >>> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
> >>> +
> >>> +	if (!debugfs_initialized())
> >>> +		return;
> >>> +
> >>> +	vfio_vf_debugfs_exit(vdev);
> >>> +	kfree(hisi_acc_vdev->debug_migf);
> >>> +}
> >>> +
> >>>  static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
> >>>  {
> >>>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
> >>> @@ -1416,6 +1692,9 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
> >>>  	if (IS_ERR(hisi_acc_vdev))
> >>>  		return PTR_ERR(hisi_acc_vdev);
> >>>  
> >>> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
> >>> +		hisi_acc_vfio_debug_init(hisi_acc_vdev);
> >>> +
> >>>  	dev_set_drvdata(&pdev->dev, &hisi_acc_vdev->core_device);
> >>>  	ret = vfio_pci_core_register_device(&hisi_acc_vdev->core_device);
> >>>  	if (ret)
> >>> @@ -1423,6 +1702,8 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
> >>>  	return 0;
> >>>  
> >>>  out_put_vdev:
> >>> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
> >>> +		hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
> >>>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
> >>>  	return ret;
> >>>  }
> >>> @@ -1431,6 +1712,7 @@ static void hisi_acc_vfio_pci_remove(struct pci_dev *pdev)
> >>>  {
> >>>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_drvdata(pdev);
> >>>  
> >>> +	hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
> >>>  	vfio_pci_core_unregister_device(&hisi_acc_vdev->core_device);
> >>>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
> >>>  }
> >>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
> >>> index dcabfeec6ca1..ef50b12f018d 100644
> >>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
> >>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
> >>> @@ -49,6 +49,14 @@
> >>>  #define QM_EQC_DW0		0X8000
> >>>  #define QM_AEQC_DW0		0X8020
> >>>  
> >>> +#define VFIO_DEV_DBG_LEN		256
> >>> +
> >>> +enum mig_debug_cmd {
> >>> +	STATE_SAVE,
> >>> +	STATE_RESUME,
> >>> +	RW_IO_TEST,
> >>> +};
> >>> +
> >>>  struct acc_vf_data {
> >>>  #define QM_MATCH_SIZE offsetofend(struct acc_vf_data, qm_rsv_state)
> >>>  	/* QM match information */
> >>> @@ -113,5 +121,8 @@ struct hisi_acc_vf_core_device {
> >>>  	spinlock_t reset_lock;
> >>>  	struct hisi_acc_vf_migration_file *resuming_migf;
> >>>  	struct hisi_acc_vf_migration_file *saving_migf;
> >>> +
> >>> +	/* For debugfs */
> >>> +	struct hisi_acc_vf_migration_file *debug_migf;
> >>>  };
> >>>  #endif /* HISI_ACC_VFIO_PCI_H */  
> >>
> >> .
> >>  
> 

Re: [PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

[liulongfang]

On 2023/3/14 23:17, Alex Williamson wrote:
> On Tue, 14 Mar 2023 19:21:29 +0800
> liulongfang <liulongfang@huawei.com> wrote:
> 
>> On 2023/3/14 19:04, liulongfang wrote:
>>> On 2023/3/11 7:40, Alex Williamson wrote:  
>>>> On Fri, 17 Feb 2023 16:48:29 +0800
>>>> Longfang Liu <liulongfang@huawei.com> wrote:
>>>>  
>>>>> On the debugfs framework of VFIO, if the CONFIG_DEBUG_FS macro is
>>>>> enabled, the debug function is registered for the live migration driver
>>>>> of the HiSilicon accelerator device.
>>>>>
>>>>> On the basis of the original public debug function, a private debug
>>>>> function is added:
>>>>>
>>>>> mig_data file: used to get the migration data of the live migration device
>>>>> mig_attr file: used to get device attributes of the live migration device
>>>>> debug file: used to test for acquiring and writing device state data
>>>>> for VF device.
>>>>>
>>>>> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
>>>>> ---
>>>>>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 282 ++++++++++++++++++
>>>>>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h    |  11 +
>>>>>  2 files changed, 293 insertions(+)
>>>>>
>>>>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>>>>> index a1589947e721..a0ecb1cd5707 100644
>>>>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>>>>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>>>>> @@ -15,6 +15,7 @@
>>>>>  #include <linux/anon_inodes.h>
>>>>>  
>>>>>  #include "hisi_acc_vfio_pci.h"
>>>>> +#include "../../vfio.h"
>>>>>  
>>>>>  /* Return 0 on VM acc device ready, -ETIMEDOUT hardware timeout */
>>>>>  static int qm_wait_dev_not_ready(struct hisi_qm *qm)
>>>>> @@ -606,6 +607,18 @@ hisi_acc_check_int_state(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>>>>  	}
>>>>>  }
>>>>>  
>>>>> +static void hisi_acc_vf_migf_save(struct hisi_acc_vf_migration_file *src_migf,
>>>>> +	struct hisi_acc_vf_migration_file *dst_migf)
>>>>> +{
>>>>> +	if (!dst_migf)
>>>>> +		return;
>>>>> +
>>>>> +	dst_migf->disabled = false;
>>>>> +	dst_migf->total_length = src_migf->total_length;
>>>>> +	memcpy(&dst_migf->vf_data, &src_migf->vf_data,
>>>>> +		    sizeof(struct acc_vf_data));
>>>>> +}
>>>>> +
>>>>>  static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
>>>>>  {
>>>>>  	mutex_lock(&migf->lock);
>>>>> @@ -618,12 +631,16 @@ static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf)
>>>>>  static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>>>>  {
>>>>>  	if (hisi_acc_vdev->resuming_migf) {
>>>>> +		hisi_acc_vf_migf_save(hisi_acc_vdev->resuming_migf,
>>>>> +						hisi_acc_vdev->debug_migf);
>>>>>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->resuming_migf);
>>>>>  		fput(hisi_acc_vdev->resuming_migf->filp);
>>>>>  		hisi_acc_vdev->resuming_migf = NULL;
>>>>>  	}
>>>>>  
>>>>>  	if (hisi_acc_vdev->saving_migf) {
>>>>> +		hisi_acc_vf_migf_save(hisi_acc_vdev->saving_migf,
>>>>> +						hisi_acc_vdev->debug_migf);
>>>>>  		hisi_acc_vf_disable_fd(hisi_acc_vdev->saving_migf);
>>>>>  		fput(hisi_acc_vdev->saving_migf->filp);
>>>>>  		hisi_acc_vdev->saving_migf = NULL;
>>>>> @@ -1303,6 +1320,265 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
>>>>>  	return vfio_pci_core_ioctl(core_vdev, cmd, arg);
>>>>>  }
>>>>>  
>>>>> +static int hisi_acc_vf_debug_io(struct vfio_device *vdev)
>>>>> +{
>>>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>>>> +	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
>>>>> +	struct device *dev = vdev->dev;
>>>>> +	u64 data;
>>>>> +	int ret;
>>>>> +
>>>>> +	ret = qm_wait_dev_not_ready(vf_qm);
>>>>> +	if (ret)
>>>>> +		dev_err(dev, "VF device not ready!\n");
>>>>> +
>>>>> +	data = readl(vf_qm->io_base + QM_MB_CMD_SEND_BASE);
>>>>> +	dev_info(dev, "debug mailbox val: 0x%llx\n", data);
>>>>> +
>>>>> +	return ret;
>>>>> +}
>>>>> +
>>>>> +static int hisi_acc_vf_debug_resume(struct vfio_device *vdev)
>>>>> +{
>>>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>>>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
>>>>> +	struct device *dev = vdev->dev;
>>>>> +	int ret;
>>>>> +
>>>>> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
>>>>> +	if (ret) {
>>>>> +		dev_err(dev, "failed to save device data!\n");
>>>>> +		return -EINVAL;
>>>>> +	}
>>>>> +
>>>>> +	ret = vf_qm_check_match(hisi_acc_vdev, migf);
>>>>> +	if (ret) {
>>>>> +		dev_err(dev, "failed to match the VF!\n");
>>>>> +		return -EINVAL;
>>>>> +	}
>>>>> +
>>>>> +	ret = vf_qm_load_data(hisi_acc_vdev, migf);
>>>>> +	if (ret) {
>>>>> +		dev_err(dev, "failed to recover the VF!\n");
>>>>> +		return -EINVAL;
>>>>> +	}
>>>>> +
>>>>> +	vf_qm_fun_reset(&hisi_acc_vdev->vf_qm);
>>>>> +	dev_info(dev, "successful to resume device data!\n");
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static int hisi_acc_vf_debug_save(struct vfio_device *vdev)
>>>>> +{
>>>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>>>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
>>>>> +	struct device *dev = vdev->dev;
>>>>> +	int ret;
>>>>> +
>>>>> +	ret = vf_qm_state_save(hisi_acc_vdev, migf);
>>>>> +	if (ret) {
>>>>> +		dev_err(dev, "failed to save device data!\n");
>>>>> +		return -EINVAL;
>>>>> +	}
>>>>> +	dev_info(dev, "successful to save device data!\n");
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static int
>>>>> +hisi_acc_vf_debug_operate(struct vfio_device *vdev, unsigned int cmd)
>>>>> +{
>>>>> +	int ret;
>>>>> +
>>>>> +	switch (cmd) {
>>>>> +	case STATE_SAVE:
>>>>> +		ret = hisi_acc_vf_debug_save(vdev);
>>>>> +		if (ret)
>>>>> +			return ret;
>>>>> +		break;
>>>>> +	case STATE_RESUME:
>>>>> +		ret = hisi_acc_vf_debug_resume(vdev);
>>>>> +		if (ret)
>>>>> +			return ret;
>>>>> +		break;
>>>>> +	case RW_IO_TEST:
>>>>> +		ret = hisi_acc_vf_debug_io(vdev);
>>>>> +		if (ret)
>>>>> +			return ret;
>>>>> +		break;
>>>>> +	default:
>>>>> +		return -EINVAL;
>>>>> +	}
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static int hisi_acc_vf_debug_check(struct vfio_device *vdev)
>>>>> +{
>>>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>>>> +	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf;
>>>>> +	enum vfio_device_mig_state state;
>>>>> +
>>>>> +	if (!vdev->mig_ops || !migf) {
>>>>> +		dev_err(vdev->dev, "device not support debugfs!\n");
>>>>> +		return -EINVAL;
>>>>> +	}
>>>>> +
>>>>> +	/* If device not opened, the debugfs operation will trigger calltrace */
>>>>> +	(void)vdev->mig_ops->migration_get_state(vdev, &state);
>>>>> +	if (state == VFIO_DEVICE_STATE_ERROR ||
>>>>> +	    state == VFIO_DEVICE_STATE_STOP) {
>>>>> +		dev_err(vdev->dev, "device not opened!\n");
>>>>> +		return -EINVAL;
>>>>> +	}
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static ssize_t hisi_acc_vf_debug_write(struct file *filp, const char __user *buffer,
>>>>> +			    size_t count, loff_t *pos)
>>>>> +{
>>>>> +	struct vfio_device	*vdev = filp->private_data;
>>>>> +	char tbuf[VFIO_DEV_DBG_LEN];
>>>>> +	unsigned long cmd;
>>>>> +	int len, ret;
>>>>> +
>>>>> +	if (*pos)
>>>>> +		return 0;
>>>>> +
>>>>> +	if (count >= VFIO_DEV_DBG_LEN)
>>>>> +		return -ENOSPC;
>>>>> +
>>>>> +	ret = hisi_acc_vf_debug_check(vdev);
>>>>> +	if (ret)
>>>>> +		return -EINVAL;
>>>>> +
>>>>> +	len = simple_write_to_buffer(tbuf, VFIO_DEV_DBG_LEN - 1,
>>>>> +					pos, buffer, count);
>>>>> +	if (len < 0 || len > VFIO_DEV_DBG_LEN - 1)
>>>>> +		return -EINVAL;
>>>>> +	tbuf[len] = '\0';
>>>>> +	if (kstrtoul(tbuf, 0, &cmd))
>>>>> +		return -EFAULT;
>>>>> +
>>>>> +	ret = hisi_acc_vf_debug_operate(vdev, cmd);
>>>>> +	if (ret) {
>>>>> +		dev_err(vdev->dev, "device debug test failed!\n");
>>>>> +		return -EINVAL;
>>>>> +	}
>>>>> +
>>>>> +	return count;
>>>>> +}
>>>>> +
>>>>> +static const struct file_operations hisi_acc_vf_debug_fops = {
>>>>> +	.owner = THIS_MODULE,
>>>>> +	.open = simple_open,
>>>>> +	.write = hisi_acc_vf_debug_write,
>>>>> +};
>>>>> +
>>>>> +static void seq_print_hex_data(struct seq_file *seq, const void *buf, size_t len)
>>>>> +{
>>>>> +#define HEX_LINE_SIZE		131
>>>>> +#define HEX_ROW_SIZE		16
>>>>> +	unsigned char linebuf[HEX_LINE_SIZE];
>>>>> +	int i, linelen, remaining = len;
>>>>> +	const u8 *ptr = buf;
>>>>> +
>>>>> +	for (i = 0; i < len; i += HEX_ROW_SIZE) {
>>>>> +		linelen = min(remaining, HEX_ROW_SIZE);
>>>>> +		remaining -= HEX_ROW_SIZE;
>>>>> +
>>>>> +		hex_dump_to_buffer(ptr + i, linelen, HEX_ROW_SIZE, 1,
>>>>> +					linebuf, sizeof(linebuf), false);
>>>>> +
>>>>> +		seq_printf(seq, "%s%.8x: %s\n", "Mig Data:", i, linebuf);
>>>>> +	}
>>>>> +}
>>>>> +
>>>>> +static int hisi_acc_vf_data_read(struct seq_file *seq, void *data)
>>>>> +{
>>>>> +	struct device *vf_dev = seq->private;
>>>>> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
>>>>> +	struct vfio_device	*vdev = &core_device->vdev;
>>>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>>>> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
>>>>> +	size_t vf_data_sz = offsetofend(struct acc_vf_data, padding);
>>>>> +
>>>>> +	if (debug_migf && debug_migf->total_length)
>>>>> +		seq_print_hex_data(seq, (unsigned char *)&debug_migf->vf_data,
>>>>> +				vf_data_sz);
>>>>> +	else
>>>>> +		seq_printf(seq, "%s\n", "device not migrated!");
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static int hisi_acc_vf_attr_read(struct seq_file *seq, void *data)
>>>>> +{
>>>>> +	struct device *vf_dev = seq->private;
>>>>> +	struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
>>>>> +	struct vfio_device	*vdev = &core_device->vdev;
>>>>> +	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev);
>>>>> +	struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf;
>>>>> +
>>>>> +	if (debug_migf && debug_migf->total_length) {
>>>>> +		seq_printf(seq,
>>>>> +			 "acc device:\n"
>>>>> +			 "device  state: %d\n"
>>>>> +			 "device  ready: %u\n"
>>>>> +			 "data    valid: %d\n"
>>>>> +			 "data     size: %lu\n",
>>>>> +			 hisi_acc_vdev->mig_state,
>>>>> +			 hisi_acc_vdev->vf_qm_state,
>>>>> +			 debug_migf->disabled,
>>>>> +			 debug_migf->total_length);
>>>>> +	} else {
>>>>> +		seq_printf(seq, "%s\n", "device not migrated!");
>>>>> +	}
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static int hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>>>> +{
>>>>> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
>>>>> +	struct device *dev = vdev->dev;
>>>>> +	void *migf = NULL;
>>>>> +
>>>>> +	if (!debugfs_initialized())
>>>>> +		return 0;
>>>>> +
>>>>> +	vfio_vf_debugfs_init(vdev);
>>>>> +
>>>>> +	migf = kzalloc(sizeof(struct hisi_acc_vf_migration_file), GFP_KERNEL);
>>>>> +	if (!migf)
>>>>> +		return -ENOMEM;
>>>>> +
>>>>> +	hisi_acc_vdev->debug_migf = migf;
>>>>> +
>>>>> +	debugfs_create_devm_seqfile(dev, "migration_data", vdev->debug_root,
>>>>> +				  hisi_acc_vf_data_read);
>>>>> +	debugfs_create_devm_seqfile(dev, "migration_attr", vdev->debug_root,
>>>>> +				  hisi_acc_vf_attr_read);
>>>>> +
>>>>> +	debugfs_create_file("migration_debug", 0200, vdev->debug_root,
>>>>> +				  vdev, &hisi_acc_vf_debug_fops);
>>>>> +  
>>>>
>>>> All of these are going to be device specific, right?  So do we really
>>>> want a debugfs file structure that looks like:
>>>>
>>>> vfio
>>>> └── migration
>>>>     ├── hisi_acc
>>>>     │   ├── attr
>>>>     │   ├── data
>>>>     │   └── debug
>>>>     └── state
>>>>  
>>>
>>> According to this directory structure, I also need to change.
>>>
>>> Thanks
>>> Longfang.  
>>
>> If there are multiple devices participating in live migration, their current directory structure
>> is like this:
>> vfio
>> ├── hisi_acc_1
>> │     ├── attr
>> │     ├── data
>> │     ├── debug
>> │     └── state
>> │
>> └── hisi_acc_2
>>        ├── attr
>>        ├── data
>>        ├── debug
>>        └── state
>>
>>
>> If you want to change to the above directory structure, which directory should the
>> ‘state’ file be placed in the case of multiple devices?
>> vfio
>>  └─ migration
>>      ├── hisi_acc
>>      │     ├── attr
>>      │     ├── data
>>      │     └── debug
>>      └── state
>>
>> Like this or other directory structure?
>> vfio
>> └─ migration
>>     ├── hisi_acc_1
>>     │     ├── attr
>>     │     ├── data
>>     │     └── debug
>>     ├── hisi_acc_2
>>     │     ├── attr
>>     │     ├── data
>>     │     └── debug
>>     └── state
>> 	   ├── hisi_acc_1
>> 	   └── hisi_acc_2> 
> 
> I was thinking:
> 
> vfio
> ├── <name1>
> │   └── migration
> │       ├── hisi_acc
> │       │   ├── attr
> │       │   ├── data
> │       │   └── debug
> │       └── state
> └── <name2>
>     └── migration
>         ├── hisi_acc
>         │   ├── attr
>         │   ├── data
>         │   └── debug
>         └── state
> 
> My concern is that if {attr,data,debug} have driver specific
> definitions, they should have their own driver specific namespace.
> Thanks,
> 

Do <name1> and <name1> refer to dev_name()?
Is the file name "hisi_acc" defined by the driver?

Thanks,
Longfang.
> Alex
> 
>  
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static void hisi_acc_vf_debugfs_exit(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>>>> +{
>>>>> +	struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
>>>>> +
>>>>> +	if (!debugfs_initialized())
>>>>> +		return;
>>>>> +
>>>>> +	vfio_vf_debugfs_exit(vdev);
>>>>> +	kfree(hisi_acc_vdev->debug_migf);
>>>>> +}
>>>>> +
>>>>>  static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev)
>>>>>  {
>>>>>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev);
>>>>> @@ -1416,6 +1692,9 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>>>>>  	if (IS_ERR(hisi_acc_vdev))
>>>>>  		return PTR_ERR(hisi_acc_vdev);
>>>>>  
>>>>> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
>>>>> +		hisi_acc_vfio_debug_init(hisi_acc_vdev);
>>>>> +
>>>>>  	dev_set_drvdata(&pdev->dev, &hisi_acc_vdev->core_device);
>>>>>  	ret = vfio_pci_core_register_device(&hisi_acc_vdev->core_device);
>>>>>  	if (ret)
>>>>> @@ -1423,6 +1702,8 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>>>>>  	return 0;
>>>>>  
>>>>>  out_put_vdev:
>>>>> +	if (ops == &hisi_acc_vfio_pci_migrn_ops)
>>>>> +		hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
>>>>>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
>>>>>  	return ret;
>>>>>  }
>>>>> @@ -1431,6 +1712,7 @@ static void hisi_acc_vfio_pci_remove(struct pci_dev *pdev)
>>>>>  {
>>>>>  	struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_drvdata(pdev);
>>>>>  
>>>>> +	hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
>>>>>  	vfio_pci_core_unregister_device(&hisi_acc_vdev->core_device);
>>>>>  	vfio_put_device(&hisi_acc_vdev->core_device.vdev);
>>>>>  }
>>>>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
>>>>> index dcabfeec6ca1..ef50b12f018d 100644
>>>>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
>>>>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
>>>>> @@ -49,6 +49,14 @@
>>>>>  #define QM_EQC_DW0		0X8000
>>>>>  #define QM_AEQC_DW0		0X8020
>>>>>  
>>>>> +#define VFIO_DEV_DBG_LEN		256
>>>>> +
>>>>> +enum mig_debug_cmd {
>>>>> +	STATE_SAVE,
>>>>> +	STATE_RESUME,
>>>>> +	RW_IO_TEST,
>>>>> +};
>>>>> +
>>>>>  struct acc_vf_data {
>>>>>  #define QM_MATCH_SIZE offsetofend(struct acc_vf_data, qm_rsv_state)
>>>>>  	/* QM match information */
>>>>> @@ -113,5 +121,8 @@ struct hisi_acc_vf_core_device {
>>>>>  	spinlock_t reset_lock;
>>>>>  	struct hisi_acc_vf_migration_file *resuming_migf;
>>>>>  	struct hisi_acc_vf_migration_file *saving_migf;
>>>>> +
>>>>> +	/* For debugfs */
>>>>> +	struct hisi_acc_vf_migration_file *debug_migf;
>>>>>  };
>>>>>  #endif /* HISI_ACC_VFIO_PCI_H */  
>>>>
>>>> .
>>>>  
>>
> 
> .
> 

Re: [PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

[Alex Williamson]

On Sat, 18 Mar 2023 17:07:38 +0800
liulongfang <liulongfang@huawei.com> wrote:

> On 2023/3/14 23:17, Alex Williamson wrote:
> > I was thinking:
> > 
> > vfio
> > ├── <name1>
> > │   └── migration
> > │       ├── hisi_acc
> > │       │   ├── attr
> > │       │   ├── data
> > │       │   └── debug
> > │       └── state
> > └── <name2>
> >     └── migration
> >         ├── hisi_acc
> >         │   ├── attr
> >         │   ├── data
> >         │   └── debug
> >         └── state
> > 
> > My concern is that if {attr,data,debug} have driver specific
> > definitions, they should have their own driver specific namespace.
> > Thanks,
> >   
> 
> Do <name1> and <name1> refer to dev_name()?

Yes

> Is the file name "hisi_acc" defined by the driver?

Yes, this is the drive defined namespace.  Thanks,

Alex