[PATCH v4 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver

Longfang Liu
2022-12-02T09:29:19Z

On the debugfs framework of VFIO, register the debug function
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, so that the single-step debugging function
during live migration can be realized.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
.../vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 250 ++++++++++++++++++
.../vfio/pci/hisilicon/hisi_acc_vfio_pci.h | 9 +
drivers/vfio/pci/vfio_pci_debugfs.c | 10 +-
3 files changed, 268 insertions(+), 1 deletion(-)

diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index eb18edffbd5f..0f35cde6e8ec 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_pci_debugfs.h"

/* Return 0 on VM acc device ready, -ETIMEDOUT hardware timeout */
static int qm_wait_dev_not_ready(struct hisi_qm *qm)
@@ -609,6 +610,18 @@ 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);
@@ -621,12 +634,16 @@ 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;
@@ -1188,6 +1205,231 @@ 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;
+
+ data = readl(vf_qm->io_base + QM_MB_CMD_SEND_BASE);
+ dev_info(dev, "debug mailbox val: 0x%llx\n", data);
+
+ ret = qm_wait_dev_not_ready(vf_qm);
+ if (ret)
+ dev_err(dev, "VF device not ready!\n");
+
+ 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 int
+hisi_acc_vfio_pci_get_device_data(struct vfio_device *vdev, char *buff)
+{
+ 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);
+ struct device *dev = vdev->dev;
+
+ if (debug_migf && debug_migf->total_length) {
+ memcpy(buff, &debug_migf->vf_data, vf_data_sz);
+ return vf_data_sz;
+ }
+ dev_info(dev, "device not migrated!\n");
+
+ return 0;
+}
+
+static int
+hisi_acc_vfio_pci_get_device_attr(struct vfio_device *vdev, char *buff)
+{
+ 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;
+ struct device *dev = vdev->dev;
+
+ if (debug_migf && debug_migf->total_length) {
+ return scnprintf(buff, VFIO_DEV_DBG_LEN,
+ "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);
+ }
+ dev_info(dev, "device not migrated!\n");
+
+ 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;
+ void *migf = NULL;
+
+ vfio_pci_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_file("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;
+
+ kfree(hisi_acc_vdev->debug_migf);
+ vfio_pci_vf_debugfs_exit(vdev);
+}
+
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);
@@ -1224,6 +1466,8 @@ static const struct vfio_migration_ops hisi_acc_vfio_pci_migrn_state_ops = {
.migration_set_state = hisi_acc_vfio_pci_set_device_state,
.migration_get_state = hisi_acc_vfio_pci_get_device_state,
.migration_get_data_size = hisi_acc_vfio_pci_get_data_size,
+ .migration_get_data = hisi_acc_vfio_pci_get_device_data,
+ .migration_get_attr = hisi_acc_vfio_pci_get_device_attr,
};

static int hisi_acc_vfio_pci_migrn_init_dev(struct vfio_device *core_vdev)
@@ -1295,6 +1539,9 @@ 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)
@@ -1302,6 +1549,8 @@ 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;
}
@@ -1310,6 +1559,7 @@ 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 67343325b320..e9d72dc0c66c 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
@@ -49,6 +49,12 @@
#define QM_EQC_DW0 0X8000
#define QM_AEQC_DW0 0X8020

+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 */
@@ -111,5 +117,8 @@ 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 */
diff --git a/drivers/vfio/pci/vfio_pci_debugfs.c b/drivers/vfio/pci/vfio_pci_debugfs.c
index 94a42869539e..a0cec2d17e16 100644
--- a/drivers/vfio/pci/vfio_pci_debugfs.c
+++ b/drivers/vfio/pci/vfio_pci_debugfs.c
@@ -8,7 +8,7 @@

#include "vfio_pci_debugfs.h"

-#define VFIO_DEV_BUF_LEN 4096
+#define VFIO_DEV_BUF_LEN 1024
static struct dentry *vfio_pci_debugfs_root;

static ssize_t vfio_pci_vf_data_dump(struct file *filp, char __user *buffer,
@@ -24,6 +24,10 @@ static ssize_t vfio_pci_vf_data_dump(struct file *filp, char __user *buffer,
}

len = vdev->mig_ops->migration_get_data(vdev, tbuf);
+ if (len < 0 || len >= VFIO_DEV_BUF_LEN) {
+ dev_err(vdev->dev, "failed to get device data!\n");
+ return -EINVAL;
+ }

return simple_read_from_buffer(buffer, count, pos, tbuf, len);
}
@@ -47,6 +51,10 @@ static ssize_t vfio_pci_vf_attr_show(struct file *filp, char __user *buffer,
}

len = vdev->mig_ops->migration_get_attr(vdev, tbuf);
+ if (len < 0 || len >= VFIO_DEV_BUF_LEN) {
+ dev_err(vdev->dev, "failed to get device attribute!\n");
+ return -EINVAL;
+ }

return simple_read_from_buffer(buffer, count, pos, tbuf, len);
}
--
2.24.0