Hi Diana, On 8/26/20 11:33 AM, Diana Craciun wrote: > Expose to userspace information about the memory regions. > > Signed-off-by: Bharat Bhushan <Bharat.Bhushan@xxxxxxx> > Signed-off-by: Diana Craciun <diana.craciun@xxxxxxxxxxx> > --- > drivers/vfio/fsl-mc/vfio_fsl_mc.c | 79 ++++++++++++++++++++++- > drivers/vfio/fsl-mc/vfio_fsl_mc_private.h | 19 ++++++ > 2 files changed, 97 insertions(+), 1 deletion(-) > > diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c > index 5a5460d01f00..093b8d68496c 100644 > --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c > +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c > @@ -17,16 +17,72 @@ > > static struct fsl_mc_driver vfio_fsl_mc_driver; > > +static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev) > +{ > + struct fsl_mc_device *mc_dev = vdev->mc_dev; > + int count = mc_dev->obj_desc.region_count; > + int i; > + > + vdev->regions = kcalloc(count, sizeof(struct vfio_fsl_mc_region), > + GFP_KERNEL); > + if (!vdev->regions) > + return -ENOMEM; > + > + for (i = 0; i < count; i++) { > + struct resource *res = &mc_dev->regions[i]; > + > + vdev->regions[i].addr = res->start; > + vdev->regions[i].size = resource_size(res); > + vdev->regions[i].flags = 0; why 0? I see in > + } > + > + vdev->num_regions = mc_dev->obj_desc.region_count; nit: you can use count directly fsl-mc-bus.c that flags can take meaningful values > + return 0; > +} > + > +static void vfio_fsl_mc_regions_cleanup(struct vfio_fsl_mc_device *vdev) > +{ > + vdev->num_regions = 0; > + kfree(vdev->regions); > +} > + > static int vfio_fsl_mc_open(void *device_data) > { > + struct vfio_fsl_mc_device *vdev = device_data; > + int ret; > + > if (!try_module_get(THIS_MODULE)) > return -ENODEV; > > + mutex_lock(&vdev->driver_lock); > + if (!vdev->refcnt) { > + ret = vfio_fsl_mc_regions_init(vdev); > + if (ret) > + goto err_reg_init; > + } > + vdev->refcnt++; > + > + mutex_unlock(&vdev->driver_lock); > + > return 0; > + > +err_reg_init: > + mutex_unlock(&vdev->driver_lock); > + module_put(THIS_MODULE); > + return ret; > } > > static void vfio_fsl_mc_release(void *device_data) > { > + struct vfio_fsl_mc_device *vdev = device_data; > + > + mutex_lock(&vdev->driver_lock); > + > + if (!(--vdev->refcnt)) > + vfio_fsl_mc_regions_cleanup(vdev); > + > + mutex_unlock(&vdev->driver_lock); > + > module_put(THIS_MODULE); > } > > @@ -59,7 +115,25 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd, > } > case VFIO_DEVICE_GET_REGION_INFO: > { > - return -ENOTTY; > + struct vfio_region_info info; > + > + minsz = offsetofend(struct vfio_region_info, offset); > + > + if (copy_from_user(&info, (void __user *)arg, minsz)) > + return -EFAULT; > + > + if (info.argsz < minsz) > + return -EINVAL; > + > + if (info.index >= vdev->num_regions) > + return -EINVAL; > + > + /* map offset to the physical address */ > + info.offset = VFIO_FSL_MC_INDEX_TO_OFFSET(info.index); > + info.size = vdev->regions[info.index].size; > + info.flags = vdev->regions[info.index].flags; > + > + return copy_to_user((void __user *)arg, &info, minsz); > } > case VFIO_DEVICE_GET_IRQ_INFO: > { > @@ -204,6 +278,7 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev) > vfio_iommu_group_put(group, dev); > return ret; > } > + mutex_init(&vdev->driver_lock); > > return ret; > } > @@ -227,6 +302,8 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev) > > mc_dev->mc_io = NULL; > > + mutex_destroy(&vdev->driver_lock); > + > vfio_iommu_group_put(mc_dev->dev.iommu_group, dev); > > return 0; > diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > index 37d61eaa58c8..818dfd3df4db 100644 > --- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > @@ -7,9 +7,28 @@ > #ifndef VFIO_FSL_MC_PRIVATE_H > #define VFIO_FSL_MC_PRIVATE_H > > +#define VFIO_FSL_MC_OFFSET_SHIFT 40 > +#define VFIO_FSL_MC_OFFSET_MASK (((u64)(1) << VFIO_FSL_MC_OFFSET_SHIFT) - 1) > + > +#define VFIO_FSL_MC_OFFSET_TO_INDEX(off) ((off) >> VFIO_FSL_MC_OFFSET_SHIFT) > + > +#define VFIO_FSL_MC_INDEX_TO_OFFSET(index) \ > + ((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT) > + > +struct vfio_fsl_mc_region { > + u32 flags; > + u32 type; > + u64 addr; > + resource_size_t size; > +}; > + > struct vfio_fsl_mc_device { > struct fsl_mc_device *mc_dev; > struct notifier_block nb; > + int refcnt; > + u32 num_regions; > + struct vfio_fsl_mc_region *regions; > + struct mutex driver_lock; > }; > > #endif /* VFIO_FSL_MC_PRIVATE_H */ > Otherwise looks good to me Thanks Eric