[PATCH v2 03/14] vfio: Introduce a vfio_uninit_group_dev() API call

Jason Gunthorpe
2021-07-20T17:45:49Z

From: Max Gurtovoy <mgurtovoy@nvidia.com>

This pairs with vfio_init_group_dev() and allows undoing any state that is
stored in the vfio_device unrelated to registration. Add appropriately
placed calls to all the drivers.

The following patch will use this to add pre-registration state for the
device set.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
Documentation/driver-api/vfio.rst | 4 ++-
drivers/vfio/fsl-mc/vfio_fsl_mc.c | 7 ++---
drivers/vfio/mdev/vfio_mdev.c | 13 +++++++---
drivers/vfio/pci/vfio_pci.c | 6 +++--
drivers/vfio/platform/vfio_platform_common.c | 7 +++--
drivers/vfio/vfio.c | 5 ++++
include/linux/vfio.h | 1 +
samples/vfio-mdev/mbochs.c | 2 ++
samples/vfio-mdev/mdpy.c | 25 ++++++++++--------
samples/vfio-mdev/mtty.c | 27 ++++++++++++--------
10 files changed, 64 insertions(+), 33 deletions(-)

diff --git a/Documentation/driver-api/vfio.rst b/Documentation/driver-api/vfio.rst
index 606eed8823ceab..c663b6f978255b 100644
--- a/Documentation/driver-api/vfio.rst
+++ b/Documentation/driver-api/vfio.rst
@@ -255,11 +255,13 @@ vfio_unregister_group_dev() respectively::
void vfio_init_group_dev(struct vfio_device *device,
struct device *dev,
const struct vfio_device_ops *ops);
+ void vfio_uninit_group_dev(struct vfio_device *device);
int vfio_register_group_dev(struct vfio_device *device);
void vfio_unregister_group_dev(struct vfio_device *device);

The driver should embed the vfio_device in its own structure and call
-vfio_init_group_dev() to pre-configure it before going to registration.
+vfio_init_group_dev() to pre-configure it before going to registration
+and call vfio_uninit_group_dev() after completing the un-registration.
vfio_register_group_dev() indicates to the core to begin tracking the
iommu_group of the specified dev and register the dev as owned by a VFIO bus
driver. Once vfio_register_group_dev() returns it is possible for userspace to
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 90cad109583b80..122997c61ba450 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -627,7 +627,7 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)

ret = vfio_fsl_mc_reflck_attach(vdev);
if (ret)
- goto out_kfree;
+ goto out_uninit;

ret = vfio_fsl_mc_init_device(vdev);
if (ret)
@@ -657,7 +657,8 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
vfio_fsl_uninit_device(vdev);
out_reflck:
vfio_fsl_mc_reflck_put(vdev->reflck);
-out_kfree:
+out_uninit:
+ vfio_uninit_group_dev(&vdev->vdev);
kfree(vdev);
out_group_put:
vfio_iommu_group_put(group, dev);
@@ -675,7 +676,7 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
dprc_remove_devices(mc_dev, NULL, 0);
vfio_fsl_uninit_device(vdev);
vfio_fsl_mc_reflck_put(vdev->reflck);
-
+ vfio_uninit_group_dev(&vdev->vdev);
kfree(vdev);
vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);

diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c
index 39ef7489fe4719..a5c77ccb24f70a 100644
--- a/drivers/vfio/mdev/vfio_mdev.c
+++ b/drivers/vfio/mdev/vfio_mdev.c
@@ -120,12 +120,16 @@ static int vfio_mdev_probe(struct mdev_device *mdev)

vfio_init_group_dev(vdev, &mdev->dev, &vfio_mdev_dev_ops);
ret = vfio_register_group_dev(vdev);
- if (ret) {
- kfree(vdev);
- return ret;
- }
+ if (ret)
+ goto out_uninit;
+
dev_set_drvdata(&mdev->dev, vdev);
return 0;
+
+out_uninit:
+ vfio_uninit_group_dev(vdev);
+ kfree(vdev);
+ return ret;
}

static void vfio_mdev_remove(struct mdev_device *mdev)
@@ -133,6 +137,7 @@ static void vfio_mdev_remove(struct mdev_device *mdev)
struct vfio_device *vdev = dev_get_drvdata(&mdev->dev);

vfio_unregister_group_dev(vdev);
+ vfio_uninit_group_dev(vdev);
kfree(vdev);
}

diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 318864d5283782..fab3715d60d4ba 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -2022,7 +2022,7 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)

ret = vfio_pci_reflck_attach(vdev);
if (ret)
- goto out_free;
+ goto out_uninit;
ret = vfio_pci_vf_init(vdev);
if (ret)
goto out_reflck;
@@ -2059,7 +2059,8 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
vfio_pci_vf_uninit(vdev);
out_reflck:
vfio_pci_reflck_put(vdev->reflck);
-out_free:
+out_uninit:
+ vfio_uninit_group_dev(&vdev->vdev);
kfree(vdev->pm_save);
kfree(vdev);
out_group_put:
@@ -2077,6 +2078,7 @@ static void vfio_pci_remove(struct pci_dev *pdev)

vfio_pci_vf_uninit(vdev);
vfio_pci_reflck_put(vdev->reflck);
+ vfio_uninit_group_dev(&vdev->vdev);
vfio_pci_vga_uninit(vdev);

vfio_iommu_group_put(pdev->dev.iommu_group, &pdev->dev);
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 703164df7637db..bdde8605178cd2 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -667,7 +667,7 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
ret = vfio_platform_of_probe(vdev, dev);

if (ret)
- return ret;
+ goto out_uninit;

vdev->device = dev;

@@ -675,7 +675,7 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
if (ret && vdev->reset_required) {
dev_err(dev, "No reset function found for device %s\n",
vdev->name);
- return ret;
+ goto out_uninit;
}

group = vfio_iommu_group_get(dev);
@@ -698,6 +698,8 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
vfio_iommu_group_put(group, dev);
put_reset:
vfio_platform_put_reset(vdev);
+out_uninit:
+ vfio_uninit_group_dev(&vdev->vdev);
return ret;
}
EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
@@ -708,6 +710,7 @@ void vfio_platform_remove_common(struct vfio_platform_device *vdev)

pm_runtime_disable(vdev->device);
vfio_platform_put_reset(vdev);
+ vfio_uninit_group_dev(&vdev->vdev);
vfio_iommu_group_put(vdev->vdev.dev->iommu_group, vdev->vdev.dev);
}
EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 02cc51ce6891a9..cc375df0fd5dda 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -749,6 +749,11 @@ void vfio_init_group_dev(struct vfio_device *device, struct device *dev,
}
EXPORT_SYMBOL_GPL(vfio_init_group_dev);

+void vfio_uninit_group_dev(struct vfio_device *device)
+{
+}
+EXPORT_SYMBOL_GPL(vfio_uninit_group_dev);
+
int vfio_register_group_dev(struct vfio_device *device)
{
struct vfio_device *existing_device;
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index a2c5b30e1763ba..b0875cf8e496bb 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -61,6 +61,7 @@ extern void vfio_iommu_group_put(struct iommu_group *group, struct device *dev);

void vfio_init_group_dev(struct vfio_device *device, struct device *dev,
const struct vfio_device_ops *ops);
+void vfio_uninit_group_dev(struct vfio_device *device);
int vfio_register_group_dev(struct vfio_device *device);
void vfio_unregister_group_dev(struct vfio_device *device);
extern struct vfio_device *vfio_device_get_from_dev(struct device *dev);
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 501845b08c0974..4ec4bc649351fc 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -560,6 +560,7 @@ static int mbochs_probe(struct mdev_device *mdev)
err_bytes:
mbochs_used_mbytes -= mdev_state->type->mbytes;
err_mem:
+ vfio_uninit_group_dev(&mdev_state->vdev);
kfree(mdev_state->pages);
kfree(mdev_state->vconfig);
kfree(mdev_state);
@@ -572,6 +573,7 @@ static void mbochs_remove(struct mdev_device *mdev)

vfio_unregister_group_dev(&mdev_state->vdev);
mbochs_used_mbytes -= mdev_state->type->mbytes;
+ vfio_uninit_group_dev(&mdev_state->vdev);
kfree(mdev_state->pages);
kfree(mdev_state->vconfig);
kfree(mdev_state);
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index a7d4ed28d66411..57334034cde6dd 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -235,17 +235,16 @@ static int mdpy_probe(struct mdev_device *mdev)

mdev_state->vconfig = kzalloc(MDPY_CONFIG_SPACE_SIZE, GFP_KERNEL);
if (mdev_state->vconfig == NULL) {
- kfree(mdev_state);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_state;
}

fbsize = roundup_pow_of_two(type->width * type->height * type->bytepp);

mdev_state->memblk = vmalloc_user(fbsize);
if (!mdev_state->memblk) {
- kfree(mdev_state->vconfig);
- kfree(mdev_state);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_vconfig;
}
dev_info(dev, "%s: %s (%dx%d)\n", __func__, type->name, type->width,
type->height);
@@ -260,13 +259,18 @@ static int mdpy_probe(struct mdev_device *mdev)
mdpy_count++;

ret = vfio_register_group_dev(&mdev_state->vdev);
- if (ret) {
- kfree(mdev_state->vconfig);
- kfree(mdev_state);
- return ret;
- }
+ if (ret)
+ goto err_mem;
dev_set_drvdata(&mdev->dev, mdev_state);
return 0;
+err_mem:
+ vfree(mdev_state->memblk);
+err_vconfig:
+ kfree(mdev_state->vconfig);
+err_state:
+ vfio_uninit_group_dev(&mdev_state->vdev);
+ kfree(mdev_state);
+ return ret;
}

static void mdpy_remove(struct mdev_device *mdev)
@@ -278,6 +282,7 @@ static void mdpy_remove(struct mdev_device *mdev)
vfio_unregister_group_dev(&mdev_state->vdev);
vfree(mdev_state->memblk);
kfree(mdev_state->vconfig);
+ vfio_uninit_group_dev(&mdev_state->vdev);
kfree(mdev_state);

mdpy_count--;
diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index 8b26fecc4afedd..37cc9067e1601d 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -718,8 +718,8 @@ static int mtty_probe(struct mdev_device *mdev)

mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
if (mdev_state == NULL) {
- atomic_add(nr_ports, &mdev_avail_ports);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_nr_ports;
}

vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mtty_dev_ops);
@@ -732,9 +732,8 @@ static int mtty_probe(struct mdev_device *mdev)
mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);

if (mdev_state->vconfig == NULL) {
- kfree(mdev_state);
- atomic_add(nr_ports, &mdev_avail_ports);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_state;
}

mutex_init(&mdev_state->ops_lock);
@@ -743,14 +742,19 @@ static int mtty_probe(struct mdev_device *mdev)
mtty_create_config_space(mdev_state);

ret = vfio_register_group_dev(&mdev_state->vdev);
- if (ret) {
- kfree(mdev_state);
- atomic_add(nr_ports, &mdev_avail_ports);
- return ret;
- }
-
+ if (ret)
+ goto err_vconfig;
dev_set_drvdata(&mdev->dev, mdev_state);
return 0;
+
+err_vconfig:
+ kfree(mdev_state->vconfig);
+err_state:
+ vfio_uninit_group_dev(&mdev_state->vdev);
+ kfree(mdev_state);
+err_nr_ports:
+ atomic_add(nr_ports, &mdev_avail_ports);
+ return ret;
}

static void mtty_remove(struct mdev_device *mdev)
@@ -761,6 +765,7 @@ static void mtty_remove(struct mdev_device *mdev)
vfio_unregister_group_dev(&mdev_state->vdev);

kfree(mdev_state->vconfig);
+ vfio_uninit_group_dev(&mdev_state->vdev);
kfree(mdev_state);
atomic_add(nr_ports, &mdev_avail_ports);
}
--
2.32.0