| Message ID | 1489178976-15353-4-git-send-email-will.deacon@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Will, On 2017-03-10 15:49, Will Deacon wrote: > arm_smmu_install_ste_for_dev cannot fail and always returns 0, however > the fact that it returns int means that callers end up implementing > redundant error handling code which complicates STE tracking and is > never executed. > > This patch changes the return type of arm_smmu_install_ste_for_dev > to avoid, to make it explicit that it cannot fail. Did you mean "a void" or just "void" instead of "avoid"? > > Signed-off-by: Will Deacon <will.deacon@arm.com> > --- > drivers/iommu/arm-smmu-v3.c | 12 +++--------- > 1 file changed, 3 insertions(+), 9 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index 3d38e682071a..e18dbcd26f66 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -1579,7 +1579,7 @@ static __le64 *arm_smmu_get_step_for_sid(struct > arm_smmu_device *smmu, u32 sid) > return step; > } > > -static int arm_smmu_install_ste_for_dev(struct iommu_fwspec *fwspec) > +static void arm_smmu_install_ste_for_dev(struct iommu_fwspec *fwspec) > { > int i; > struct arm_smmu_master_data *master = fwspec->iommu_priv; > @@ -1591,8 +1591,6 @@ static int arm_smmu_install_ste_for_dev(struct > iommu_fwspec *fwspec) > > arm_smmu_write_strtab_ent(smmu, sid, step, &master->ste); > } > - > - return 0; > } > > static void arm_smmu_detach_dev(struct device *dev) > @@ -1600,8 +1598,7 @@ static void arm_smmu_detach_dev(struct device > *dev) > struct arm_smmu_master_data *master = dev->iommu_fwspec->iommu_priv; > > master->ste.bypass = true; > - if (arm_smmu_install_ste_for_dev(dev->iommu_fwspec) < 0) > - dev_warn(dev, "failed to install bypass STE\n"); > + arm_smmu_install_ste_for_dev(dev->iommu_fwspec); > } > > static int arm_smmu_attach_dev(struct iommu_domain *domain, struct > device *dev) > @@ -1653,10 +1650,7 @@ static int arm_smmu_attach_dev(struct > iommu_domain *domain, struct device *dev) > ste->s2_cfg = &smmu_domain->s2_cfg; > } > > - ret = arm_smmu_install_ste_for_dev(dev->iommu_fwspec); > - if (ret < 0) > - ste->valid = false; > - > + arm_smmu_install_ste_for_dev(dev->iommu_fwspec); > out_unlock: > mutex_unlock(&smmu_domain->init_mutex); > return ret;
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 3d38e682071a..e18dbcd26f66 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1579,7 +1579,7 @@ static __le64 *arm_smmu_get_step_for_sid(struct arm_smmu_device *smmu, u32 sid) return step; } -static int arm_smmu_install_ste_for_dev(struct iommu_fwspec *fwspec) +static void arm_smmu_install_ste_for_dev(struct iommu_fwspec *fwspec) { int i; struct arm_smmu_master_data *master = fwspec->iommu_priv; @@ -1591,8 +1591,6 @@ static int arm_smmu_install_ste_for_dev(struct iommu_fwspec *fwspec) arm_smmu_write_strtab_ent(smmu, sid, step, &master->ste); } - - return 0; } static void arm_smmu_detach_dev(struct device *dev) @@ -1600,8 +1598,7 @@ static void arm_smmu_detach_dev(struct device *dev) struct arm_smmu_master_data *master = dev->iommu_fwspec->iommu_priv; master->ste.bypass = true; - if (arm_smmu_install_ste_for_dev(dev->iommu_fwspec) < 0) - dev_warn(dev, "failed to install bypass STE\n"); + arm_smmu_install_ste_for_dev(dev->iommu_fwspec); } static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) @@ -1653,10 +1650,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) ste->s2_cfg = &smmu_domain->s2_cfg; } - ret = arm_smmu_install_ste_for_dev(dev->iommu_fwspec); - if (ret < 0) - ste->valid = false; - + arm_smmu_install_ste_for_dev(dev->iommu_fwspec); out_unlock: mutex_unlock(&smmu_domain->init_mutex); return ret;
arm_smmu_install_ste_for_dev cannot fail and always returns 0, however the fact that it returns int means that callers end up implementing redundant error handling code which complicates STE tracking and is never executed. This patch changes the return type of arm_smmu_install_ste_for_dev to avoid, to make it explicit that it cannot fail. Signed-off-by: Will Deacon <will.deacon@arm.com> --- drivers/iommu/arm-smmu-v3.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-)