| Message ID | 1636441347-133850-8-git-send-email-fnu.vikram@xilinx.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | dynamic node programming using overlay dtbo | expand |
Hi, On 09/11/2021 08:02, Vikram Garhwal wrote: > Add remove_device callback for removing the device entry from smmu-master using > following steps: > 1. Find if SMMU master exists for the device node. > 2. Remove the SMMU master The commit title and message doesn't match the code. > > Signed-off-by: Vikram Garhwal <fnu.vikram@xilinx.com> > --- > xen/drivers/passthrough/device_tree.c | 30 ++++++++++++++++++++++++++++++ > xen/include/xen/iommu.h | 2 ++ > 2 files changed, 32 insertions(+) > > diff --git a/xen/drivers/passthrough/device_tree.c b/xen/drivers/passthrough/device_tree.c > index 98f2aa0..9d9eed8 100644 > --- a/xen/drivers/passthrough/device_tree.c > +++ b/xen/drivers/passthrough/device_tree.c > @@ -127,6 +127,36 @@ int iommu_release_dt_devices(struct domain *d) > return 0; > } > > +int iommu_remove_dt_device(struct dt_device_node *np) > +{ > + const struct iommu_ops *ops = iommu_get_ops(); > + struct device *dev = dt_to_dev(np); > + int rc; > + > + if ( !ops ) > + return -EOPNOTSUPP; > + > + if ( iommu_dt_device_is_assigned(np) ) > + return -EPERM; EPERM means the caller doesn't have the permission to request it. However, dom0 will have the permission to remote the device. The problem is the device is currently assigned to a domain. So it would be better to return EBUSY. Also, most of the function wants to be protected with dtdevs_lock to prevent concurrent access to add/remove/assign/deassign. I would create a version of iommu_dt_device_is_assigned() (maybe called iommu_dt_device_is_assigned_locked()) that would do the same but with the caller hold the lock. > + > + /* > + * The driver which supports generic IOMMU DT bindings must have > + * these callback implemented. > + */ > + if ( !ops->remove_device ) > + return -EOPNOTSUPP; > + > + /* > + * Remove master device from the IOMMU if latter is present and available. > + */ > + rc = ops->remove_device(0, dev); > + > + if ( rc == 0 ) > + iommu_fwspec_free(dev); > + > + return rc; > +} > + > int iommu_add_dt_device(struct dt_device_node *np) > { > const struct iommu_ops *ops = iommu_get_ops(); > diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h > index 6b2cdff..c4d5d12 100644 > --- a/xen/include/xen/iommu.h > +++ b/xen/include/xen/iommu.h > @@ -215,6 +215,8 @@ int iommu_release_dt_devices(struct domain *d); > */ > int iommu_add_dt_device(struct dt_device_node *np); > > +int iommu_remove_dt_device(struct dt_device_node *np); > + > int iommu_do_dt_domctl(struct xen_domctl *, struct domain *, > XEN_GUEST_HANDLE_PARAM(xen_domctl_t)); > Cheers,
diff --git a/xen/drivers/passthrough/device_tree.c b/xen/drivers/passthrough/device_tree.c index 98f2aa0..9d9eed8 100644 --- a/xen/drivers/passthrough/device_tree.c +++ b/xen/drivers/passthrough/device_tree.c @@ -127,6 +127,36 @@ int iommu_release_dt_devices(struct domain *d) return 0; } +int iommu_remove_dt_device(struct dt_device_node *np) +{ + const struct iommu_ops *ops = iommu_get_ops(); + struct device *dev = dt_to_dev(np); + int rc; + + if ( !ops ) + return -EOPNOTSUPP; + + if ( iommu_dt_device_is_assigned(np) ) + return -EPERM; + + /* + * The driver which supports generic IOMMU DT bindings must have + * these callback implemented. + */ + if ( !ops->remove_device ) + return -EOPNOTSUPP; + + /* + * Remove master device from the IOMMU if latter is present and available. + */ + rc = ops->remove_device(0, dev); + + if ( rc == 0 ) + iommu_fwspec_free(dev); + + return rc; +} + int iommu_add_dt_device(struct dt_device_node *np) { const struct iommu_ops *ops = iommu_get_ops(); diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h index 6b2cdff..c4d5d12 100644 --- a/xen/include/xen/iommu.h +++ b/xen/include/xen/iommu.h @@ -215,6 +215,8 @@ int iommu_release_dt_devices(struct domain *d); */ int iommu_add_dt_device(struct dt_device_node *np); +int iommu_remove_dt_device(struct dt_device_node *np); + int iommu_do_dt_domctl(struct xen_domctl *, struct domain *, XEN_GUEST_HANDLE_PARAM(xen_domctl_t));
Add remove_device callback for removing the device entry from smmu-master using following steps: 1. Find if SMMU master exists for the device node. 2. Remove the SMMU master Signed-off-by: Vikram Garhwal <fnu.vikram@xilinx.com> --- xen/drivers/passthrough/device_tree.c | 30 ++++++++++++++++++++++++++++++ xen/include/xen/iommu.h | 2 ++ 2 files changed, 32 insertions(+)