Only the DPRC object allocates interrupts from the MSI
interrupt domain. The interrupts are managed by the DPRC in
a pool of interrupts. The access to this pool of interrupts
has to be protected with a lock.
This patch extends the current lock implementation to have a
lock per DPRC.
Signed-off-by: Diana Craciun <[email protected]>
---
drivers/vfio/fsl-mc/vfio_fsl_mc.c | 91 +++++++++++++++++++++--
drivers/vfio/fsl-mc/vfio_fsl_mc_private.h | 8 +-
2 files changed, 91 insertions(+), 8 deletions(-)
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 64d5c1fff51f..bbd3365e877e 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -17,6 +17,77 @@
static struct fsl_mc_driver vfio_fsl_mc_driver;
+static DEFINE_MUTEX(reflck_lock);
+
+static void vfio_fsl_mc_reflck_get(struct vfio_fsl_mc_reflck *reflck)
+{
+ kref_get(&reflck->kref);
+}
+
+static void vfio_fsl_mc_reflck_release(struct kref *kref)
+{
+ struct vfio_fsl_mc_reflck *reflck = container_of(kref,
+ struct vfio_fsl_mc_reflck,
+ kref);
+
+ mutex_destroy(&reflck->lock);
+ kfree(reflck);
+ mutex_unlock(&reflck_lock);
+}
+
+static void vfio_fsl_mc_reflck_put(struct vfio_fsl_mc_reflck *reflck)
+{
+ kref_put_mutex(&reflck->kref, vfio_fsl_mc_reflck_release, &reflck_lock);
+}
+
+static struct vfio_fsl_mc_reflck *vfio_fsl_mc_reflck_alloc(void)
+{
+ struct vfio_fsl_mc_reflck *reflck;
+
+ reflck = kzalloc(sizeof(*reflck), GFP_KERNEL);
+ if (!reflck)
+ return ERR_PTR(-ENOMEM);
+
+ kref_init(&reflck->kref);
+ mutex_init(&reflck->lock);
+
+ return reflck;
+}
+
+static int vfio_fsl_mc_reflck_attach(struct vfio_fsl_mc_device *vdev)
+{
+ int ret = 0;
+
+ mutex_lock(&reflck_lock);
+ if (is_fsl_mc_bus_dprc(vdev->mc_dev)) {
+ vdev->reflck = vfio_fsl_mc_reflck_alloc();
+ } else {
+ struct device *mc_cont_dev = vdev->mc_dev->dev.parent;
+ struct vfio_device *device;
+ struct vfio_fsl_mc_device *cont_vdev;
+
+ device = vfio_device_get_from_dev(mc_cont_dev);
+ if (!device) {
+ ret = -ENODEV;
+ goto unlock;
+ }
+
+ cont_vdev = vfio_device_data(device);
+ if (!cont_vdev->reflck) {
+ vfio_device_put(device);
+ ret = -ENODEV;
+ goto unlock;
+ }
+ vfio_fsl_mc_reflck_get(cont_vdev->reflck);
+ vdev->reflck = cont_vdev->reflck;
+ vfio_device_put(device);
+ }
+
+unlock:
+ mutex_unlock(&reflck_lock);
+ return ret;
+}
+
static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
{
struct fsl_mc_device *mc_dev = vdev->mc_dev;
@@ -55,7 +126,7 @@ static int vfio_fsl_mc_open(void *device_data)
if (!try_module_get(THIS_MODULE))
return -ENODEV;
- mutex_lock(&vdev->driver_lock);
+ mutex_lock(&vdev->reflck->lock);
if (!vdev->refcnt) {
ret = vfio_fsl_mc_regions_init(vdev);
if (ret)
@@ -63,12 +134,12 @@ static int vfio_fsl_mc_open(void *device_data)
}
vdev->refcnt++;
- mutex_unlock(&vdev->driver_lock);
+ mutex_unlock(&vdev->reflck->lock);
return 0;
err_reg_init:
- mutex_unlock(&vdev->driver_lock);
+ mutex_unlock(&vdev->reflck->lock);
module_put(THIS_MODULE);
return ret;
}
@@ -77,12 +148,12 @@ static void vfio_fsl_mc_release(void *device_data)
{
struct vfio_fsl_mc_device *vdev = device_data;
- mutex_lock(&vdev->driver_lock);
+ mutex_lock(&vdev->reflck->lock);
if (!(--vdev->refcnt))
vfio_fsl_mc_regions_cleanup(vdev);
- mutex_unlock(&vdev->driver_lock);
+ mutex_unlock(&vdev->reflck->lock);
module_put(THIS_MODULE);
}
@@ -329,12 +400,18 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
return ret;
}
+ ret = vfio_fsl_mc_reflck_attach(vdev);
+ if (ret) {
+ vfio_iommu_group_put(group, dev);
+ return ret;
+ }
+
ret = vfio_fsl_mc_init_device(vdev);
if (ret < 0) {
+ vfio_fsl_mc_reflck_put(vdev->reflck);
vfio_iommu_group_put(group, dev);
return ret;
}
- mutex_init(&vdev->driver_lock);
return ret;
}
@@ -358,7 +435,7 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
mc_dev->mc_io = NULL;
- mutex_destroy(&vdev->driver_lock);
+ vfio_fsl_mc_reflck_put(vdev->reflck);
vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index 818dfd3df4db..3b85d930e060 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -15,6 +15,11 @@
#define VFIO_FSL_MC_INDEX_TO_OFFSET(index) \
((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT)
+struct vfio_fsl_mc_reflck {
+ struct kref kref;
+ struct mutex lock;
+};
+
struct vfio_fsl_mc_region {
u32 flags;
u32 type;
@@ -28,7 +33,8 @@ struct vfio_fsl_mc_device {
int refcnt;
u32 num_regions;
struct vfio_fsl_mc_region *regions;
- struct mutex driver_lock;
+ struct vfio_fsl_mc_reflck *reflck;
+
};
#endif /* VFIO_FSL_MC_PRIVATE_H */
--
2.17.1
Hi Diana
On 8/26/20 11:33 AM, Diana Craciun wrote:
> Only the DPRC object allocates interrupts from the MSI
> interrupt domain. The interrupts are managed by the DPRC in
> a pool of interrupts. The access to this pool of interrupts
> has to be protected with a lock.
> This patch extends the current lock implementation to have a
> lock per DPRC.
>
> Signed-off-by: Diana Craciun <[email protected]>
> ---
> drivers/vfio/fsl-mc/vfio_fsl_mc.c | 91 +++++++++++++++++++++--
> drivers/vfio/fsl-mc/vfio_fsl_mc_private.h | 8 +-
> 2 files changed, 91 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> index 64d5c1fff51f..bbd3365e877e 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> @@ -17,6 +17,77 @@
>
> static struct fsl_mc_driver vfio_fsl_mc_driver;
>
> +static DEFINE_MUTEX(reflck_lock);
> +
> +static void vfio_fsl_mc_reflck_get(struct vfio_fsl_mc_reflck *reflck)
> +{
> + kref_get(&reflck->kref);
> +}
> +
> +static void vfio_fsl_mc_reflck_release(struct kref *kref)
> +{
> + struct vfio_fsl_mc_reflck *reflck = container_of(kref,
> + struct vfio_fsl_mc_reflck,
> + kref);
> +
> + mutex_destroy(&reflck->lock);
> + kfree(reflck);
> + mutex_unlock(&reflck_lock);
> +}
> +
> +static void vfio_fsl_mc_reflck_put(struct vfio_fsl_mc_reflck *reflck)
> +{
> + kref_put_mutex(&reflck->kref, vfio_fsl_mc_reflck_release, &reflck_lock);
> +}
> +
> +static struct vfio_fsl_mc_reflck *vfio_fsl_mc_reflck_alloc(void)
> +{
> + struct vfio_fsl_mc_reflck *reflck;
> +
> + reflck = kzalloc(sizeof(*reflck), GFP_KERNEL);
> + if (!reflck)
> + return ERR_PTR(-ENOMEM);
> +
> + kref_init(&reflck->kref);
> + mutex_init(&reflck->lock);
> +
> + return reflck;
> +}
> +
> +static int vfio_fsl_mc_reflck_attach(struct vfio_fsl_mc_device *vdev)
> +{
> + int ret = 0;
> +
> + mutex_lock(&reflck_lock);
> + if (is_fsl_mc_bus_dprc(vdev->mc_dev)) {
> + vdev->reflck = vfio_fsl_mc_reflck_alloc();
this can fail and if this happens I guess you shouldn't return 0.
> + } else {
> + struct device *mc_cont_dev = vdev->mc_dev->dev.parent;
> + struct vfio_device *device;
> + struct vfio_fsl_mc_device *cont_vdev;
> +
> + device = vfio_device_get_from_dev(mc_cont_dev);
> + if (!device) {
> + ret = -ENODEV;
> + goto unlock;
> + }
> +
> + cont_vdev = vfio_device_data(device);
are we sure cont_mdev always is != NULL?
> + if (!cont_vdev->reflck) {
> + vfio_device_put(device);
> + ret = -ENODEV;
> + goto unlock;
> + }
> + vfio_fsl_mc_reflck_get(cont_vdev->reflck);
> + vdev->reflck = cont_vdev->reflck;
> + vfio_device_put(device);
> + }
> +
> +unlock:
> + mutex_unlock(&reflck_lock);
> + return ret;
> +}
> +
> static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
> {
> struct fsl_mc_device *mc_dev = vdev->mc_dev;
> @@ -55,7 +126,7 @@ static int vfio_fsl_mc_open(void *device_data)
> if (!try_module_get(THIS_MODULE))
> return -ENODEV;
>
> - mutex_lock(&vdev->driver_lock);
> + mutex_lock(&vdev->reflck->lock);
> if (!vdev->refcnt) {
> ret = vfio_fsl_mc_regions_init(vdev);
> if (ret)
> @@ -63,12 +134,12 @@ static int vfio_fsl_mc_open(void *device_data)
> }
> vdev->refcnt++;
>
> - mutex_unlock(&vdev->driver_lock);
> + mutex_unlock(&vdev->reflck->lock);
>
> return 0;
>
> err_reg_init:
> - mutex_unlock(&vdev->driver_lock);
> + mutex_unlock(&vdev->reflck->lock);
> module_put(THIS_MODULE);
> return ret;
> }
> @@ -77,12 +148,12 @@ static void vfio_fsl_mc_release(void *device_data)
> {
> struct vfio_fsl_mc_device *vdev = device_data;
>
> - mutex_lock(&vdev->driver_lock);
> + mutex_lock(&vdev->reflck->lock);
>
> if (!(--vdev->refcnt))
> vfio_fsl_mc_regions_cleanup(vdev);
>
> - mutex_unlock(&vdev->driver_lock);
> + mutex_unlock(&vdev->reflck->lock);
>
> module_put(THIS_MODULE);
> }
> @@ -329,12 +400,18 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
> return ret;
> }
>
> + ret = vfio_fsl_mc_reflck_attach(vdev);
> + if (ret) {
> + vfio_iommu_group_put(group, dev);
> + return ret;
> + }
> +
> ret = vfio_fsl_mc_init_device(vdev);
> if (ret < 0) {
> + vfio_fsl_mc_reflck_put(vdev->reflck);
> vfio_iommu_group_put(group, dev);
> return ret;
> }
> - mutex_init(&vdev->driver_lock);
>
> return ret;
> }
> @@ -358,7 +435,7 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
>
> mc_dev->mc_io = NULL;
>
> - mutex_destroy(&vdev->driver_lock);
> + vfio_fsl_mc_reflck_put(vdev->reflck);
>
> vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);
>
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> index 818dfd3df4db..3b85d930e060 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> @@ -15,6 +15,11 @@
> #define VFIO_FSL_MC_INDEX_TO_OFFSET(index) \
> ((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT)
>
> +struct vfio_fsl_mc_reflck {
> + struct kref kref;
> + struct mutex lock;
> +};
> +
> struct vfio_fsl_mc_region {
> u32 flags;
> u32 type;
> @@ -28,7 +33,8 @@ struct vfio_fsl_mc_device {
> int refcnt;
> u32 num_regions;
> struct vfio_fsl_mc_region *regions;
> - struct mutex driver_lock;
> + struct vfio_fsl_mc_reflck *reflck;
> +
> };
>
> #endif /* VFIO_FSL_MC_PRIVATE_H */
>
Thanks
Eric