Commit 3832862e authored by Robin Murphy's avatar Robin Murphy Committed by Joerg Roedel
Browse files

iommu: Keep dev->iommu state consistent 



At the moment, if of_iommu_configure() allocates dev->iommu itself via
iommu_fwspec_init(), then suffers a DT parsing failure, it cleans up the
fwspec but leaves the empty dev_iommu hanging around. So far this is
benign (if a tiny bit wasteful), but we'd like to be able to reason
about dev->iommu having a consistent and unambiguous lifecycle. Thus
make sure that the of_iommu cleanup undoes precisely whatever it did.

Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/d219663a3f23001f23d520a883ac622d70b4e642.1740753261.git.robin.murphy@arm.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent fd598f71

drivers/iommu/iommu-priv.h

+2 −0
Original line number Diff line number Diff line
@@ -17,6 +17,8 @@ static inline const struct iommu_ops *dev_iommu_ops(struct device *dev) 
	return dev->iommu->iommu_dev->ops;

}



void dev_iommu_free(struct device *dev);



const struct iommu_ops *iommu_ops_from_fwnode(const struct fwnode_handle *fwnode);



static inline const struct iommu_ops *iommu_fwspec_ops(struct iommu_fwspec *fwspec)

drivers/iommu/iommu.c

+1 −1
Original line number Diff line number Diff line
@@ -355,7 +355,7 @@ static struct dev_iommu *dev_iommu_get(struct device *dev) 
	return param;

}



static void dev_iommu_free(struct device *dev)

void dev_iommu_free(struct device *dev)

{

	struct dev_iommu *param = dev->iommu;

drivers/iommu/of_iommu.c

+5 −1
Original line number Diff line number Diff line
@@ -116,6 +116,7 @@ static void of_pci_check_device_ats(struct device *dev, struct device_node *np) 
int of_iommu_configure(struct device *dev, struct device_node *master_np,

		       const u32 *id)

{

	bool dev_iommu_present;

	int err;



	if (!master_np)
@@ -127,6 +128,7 @@ int of_iommu_configure(struct device *dev, struct device_node *master_np, 
		mutex_unlock(&iommu_probe_device_lock);

		return 0;

	}

	dev_iommu_present = dev->iommu;



	/*

	 * We don't currently walk up the tree looking for a parent IOMMU.
@@ -147,8 +149,10 @@ int of_iommu_configure(struct device *dev, struct device_node *master_np, 
		err = of_iommu_configure_device(master_np, dev, id);

	}



	if (err)

	if (err && dev_iommu_present)

		iommu_fwspec_free(dev);

	else if (err && dev->iommu)

		dev_iommu_free(dev);

	mutex_unlock(&iommu_probe_device_lock);



	if (!err && dev->bus)