summaryrefslogtreecommitdiff
path: root/drivers/iommu
diff options
context:
space:
mode:
authorWill Deacon <will@kernel.org>2020-01-15 18:35:16 +0300
committerWill Deacon <will@kernel.org>2020-01-15 19:30:28 +0300
commit92c1d360dcda0ebd49253c0899bfeeb117be91fe (patch)
treec292d09a111905911bb616e66f72770a1e7c55c8 /drivers/iommu
parenta2be6218e649fb6e444e468dae5d177eea64d328 (diff)
downloadlinux-92c1d360dcda0ebd49253c0899bfeeb117be91fe.tar.xz
iommu/arm-smmu-v3: Return -EBUSY when trying to re-add a device
Although we WARN in arm_smmu_add_device() if the device being added has been added already without a subsequent call to arm_smmu_remove_device(), we still continue half-heartedly, initialising the stream-table for any new StreamIDs that may have magically appeared and re-establishing device links that should still be there from last time. Given that calling ->add_device() twice without removing the device in the meantime is indicative of an error in the caller, just return -EBUSY after warning. Cc: Robin Murphy <robin.murphy@arm.com> Cc: Jean Philippe-Brucker <jean-philippe@linaro.org> Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'drivers/iommu')
-rw-r--r--drivers/iommu/arm-smmu-v3.c37
1 files changed, 16 insertions, 21 deletions
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 59dbd63a2aae..5e04c1f3992a 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -2794,28 +2794,23 @@ static int arm_smmu_add_device(struct device *dev)
if (!fwspec || fwspec->ops != &arm_smmu_ops)
return -ENODEV;
- /*
- * We _can_ actually withstand dodgy bus code re-calling add_device()
- * without an intervening remove_device()/of_xlate() sequence, but
- * we're not going to do so quietly...
- */
- if (WARN_ON_ONCE(fwspec->iommu_priv)) {
- master = fwspec->iommu_priv;
- smmu = master->smmu;
- } else {
- smmu = arm_smmu_get_by_fwnode(fwspec->iommu_fwnode);
- if (!smmu)
- return -ENODEV;
- master = kzalloc(sizeof(*master), GFP_KERNEL);
- if (!master)
- return -ENOMEM;
- master->dev = dev;
- master->smmu = smmu;
- master->sids = fwspec->ids;
- master->num_sids = fwspec->num_ids;
- fwspec->iommu_priv = master;
- }
+ if (WARN_ON_ONCE(fwspec->iommu_priv))
+ return -EBUSY;
+
+ smmu = arm_smmu_get_by_fwnode(fwspec->iommu_fwnode);
+ if (!smmu)
+ return -ENODEV;
+
+ master = kzalloc(sizeof(*master), GFP_KERNEL);
+ if (!master)
+ return -ENOMEM;
+
+ master->dev = dev;
+ master->smmu = smmu;
+ master->sids = fwspec->ids;
+ master->num_sids = fwspec->num_ids;
+ fwspec->iommu_priv = master;
/* Check the SIDs are in range of the SMMU and our stream table */
for (i = 0; i < master->num_sids; i++) {