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vfio/fsl-mc: Added lock support in preparation for interrupt handling

Browse source 
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 <diana.craciun@oss.nxp.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Diana Craciun 2020-10-05 20:36:50 +03:00 committed by Alex Williamson
parent 6724728968
commit f2ba7e8c94
2 changed files with 90 additions and 9 deletions
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92
drivers/vfio/fsl-mc/vfio_fsl_mc.c
View file

@ -17,6 +17,78 @@
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;
mutex_lock(&reflck_lock);
if (is_fsl_mc_bus_dprc(vdev->mc_dev)) {
vdev->reflck = vfio_fsl_mc_reflck_alloc();
ret = PTR_ERR_OR_ZERO(vdev->reflck);
} 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 || !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;
@ -62,7 +134,7 @@ 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)
@ -70,12 +142,12 @@ 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;
}
@ -84,12 +156,12 @@ 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);
}
@ -343,14 +415,18 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
goto out_group_put;
}
ret = vfio_fsl_mc_init_device(vdev);
ret = vfio_fsl_mc_reflck_attach(vdev);
if (ret)
goto out_group_dev;
mutex_init(&vdev->driver_lock);
ret = vfio_fsl_mc_init_device(vdev);
if (ret)
goto out_reflck;
return 0;
out_reflck:
vfio_fsl_mc_reflck_put(vdev->reflck);
out_group_dev:
vfio_del_group_dev(dev);
out_group_put:
@ -367,7 +443,7 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
if (!vdev)
return -EINVAL;
mutex_destroy(&vdev->driver_lock);
vfio_fsl_mc_reflck_put(vdev->reflck);
if (is_fsl_mc_bus_dprc(mc_dev)) {
dprc_remove_devices(mc_dev, NULL, 0);

7
drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
View file

@ -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;
@ -27,7 +32,7 @@ struct vfio_fsl_mc_device {
struct notifier_block nb;
int refcnt;
struct vfio_fsl_mc_region *regions;
struct mutex driver_lock;
struct vfio_fsl_mc_reflck *reflck;
};
#endif /* VFIO_FSL_MC_PRIVATE_H */