| Message ID | 4f9444c7224ea0e6e4cef8ddbf77bb5292a383e3.1536935328.git.robin.murphy@arm.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | Add non-strict mode support for iommu-dma | expand |
On Fri, Sep 14, 2018 at 03:30:23PM +0100, Robin Murphy wrote: > From: Zhen Lei <thunder.leizhen@huawei.com> > > Dynamically choose strict or non-strict mode for page table config based > on the iommu domain type. It's the domain type in conjunction with the attribute that determines whether we use lazy or strict invalidation. > Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> > [rm: convert to domain attribute] > Signed-off-by: Robin Murphy <robin.murphy@arm.com> > --- > drivers/iommu/arm-smmu-v3.c | 30 ++++++++++++++++++++++++------ > 1 file changed, 24 insertions(+), 6 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index f10c852479fc..7bbfa5f7ce8e 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -612,6 +612,7 @@ struct arm_smmu_domain { > struct mutex init_mutex; /* Protects smmu pointer */ > > struct io_pgtable_ops *pgtbl_ops; > + bool non_strict; > > enum arm_smmu_domain_stage stage; > union { > @@ -1633,6 +1634,9 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain) > if (smmu->features & ARM_SMMU_FEAT_COHERENCY) > pgtbl_cfg.quirks = IO_PGTABLE_QUIRK_NO_DMA; > > + if (smmu_domain->non_strict) > + pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_NON_STRICT; > + > pgtbl_ops = alloc_io_pgtable_ops(fmt, &pgtbl_cfg, smmu_domain); > if (!pgtbl_ops) > return -ENOMEM; > @@ -1934,13 +1938,17 @@ static int arm_smmu_domain_get_attr(struct iommu_domain *domain, > { > struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); > > - if (domain->type != IOMMU_DOMAIN_UNMANAGED) > - return -EINVAL; > - > switch (attr) { > case DOMAIN_ATTR_NESTING: > + if (domain->type != IOMMU_DOMAIN_UNMANAGED) > + return -EINVAL; > *(int *)data = (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED); > return 0; > + case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE: > + if (domain->type != IOMMU_DOMAIN_DMA) > + return -EINVAL; > + *(int *)data = smmu_domain->non_strict; > + return 0; > default: > return -ENODEV; Hmm, there's a change in behaviour here (and also in the set function) which is that unknown attributes now return -ENODEV for managed domains instead of -EINVAL. I don't know if that's a problem, but I'd be inclined to switch on the domain type and then have a nested switch for the supported attributes. Will
On 2018-09-18 6:10 PM, Will Deacon wrote: > On Fri, Sep 14, 2018 at 03:30:23PM +0100, Robin Murphy wrote: >> From: Zhen Lei <thunder.leizhen@huawei.com> >> >> Dynamically choose strict or non-strict mode for page table config based >> on the iommu domain type. > > It's the domain type in conjunction with the attribute that determines > whether we use lazy or strict invalidation. > >> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> >> [rm: convert to domain attribute] >> Signed-off-by: Robin Murphy <robin.murphy@arm.com> >> --- >> drivers/iommu/arm-smmu-v3.c | 30 ++++++++++++++++++++++++------ >> 1 file changed, 24 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c >> index f10c852479fc..7bbfa5f7ce8e 100644 >> --- a/drivers/iommu/arm-smmu-v3.c >> +++ b/drivers/iommu/arm-smmu-v3.c >> @@ -612,6 +612,7 @@ struct arm_smmu_domain { >> struct mutex init_mutex; /* Protects smmu pointer */ >> >> struct io_pgtable_ops *pgtbl_ops; >> + bool non_strict; >> >> enum arm_smmu_domain_stage stage; >> union { >> @@ -1633,6 +1634,9 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain) >> if (smmu->features & ARM_SMMU_FEAT_COHERENCY) >> pgtbl_cfg.quirks = IO_PGTABLE_QUIRK_NO_DMA; >> >> + if (smmu_domain->non_strict) >> + pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_NON_STRICT; >> + >> pgtbl_ops = alloc_io_pgtable_ops(fmt, &pgtbl_cfg, smmu_domain); >> if (!pgtbl_ops) >> return -ENOMEM; >> @@ -1934,13 +1938,17 @@ static int arm_smmu_domain_get_attr(struct iommu_domain *domain, >> { >> struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); >> >> - if (domain->type != IOMMU_DOMAIN_UNMANAGED) >> - return -EINVAL; >> - >> switch (attr) { >> case DOMAIN_ATTR_NESTING: >> + if (domain->type != IOMMU_DOMAIN_UNMANAGED) >> + return -EINVAL; >> *(int *)data = (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED); >> return 0; >> + case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE: >> + if (domain->type != IOMMU_DOMAIN_DMA) >> + return -EINVAL; >> + *(int *)data = smmu_domain->non_strict; >> + return 0; >> default: >> return -ENODEV; > > Hmm, there's a change in behaviour here (and also in the set function) > which is that unknown attributes now return -ENODEV for managed domains > instead of -EINVAL. I don't know if that's a problem, but I'd be inclined > to switch on the domain type and then have a nested switch for the supported > attributes. Sure, a nested switch did actually cross my mind, but I was worried it might be a little boilerplate-heavy since there's still only one of each case (and this quick'n'dirty copy-paste job didn't need any thought...) If that's your preference too, though, I'll respin both driver patches that way. Robin.
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index f10c852479fc..7bbfa5f7ce8e 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -612,6 +612,7 @@ struct arm_smmu_domain { struct mutex init_mutex; /* Protects smmu pointer */ struct io_pgtable_ops *pgtbl_ops; + bool non_strict; enum arm_smmu_domain_stage stage; union { @@ -1633,6 +1634,9 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain) if (smmu->features & ARM_SMMU_FEAT_COHERENCY) pgtbl_cfg.quirks = IO_PGTABLE_QUIRK_NO_DMA; + if (smmu_domain->non_strict) + pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_NON_STRICT; + pgtbl_ops = alloc_io_pgtable_ops(fmt, &pgtbl_cfg, smmu_domain); if (!pgtbl_ops) return -ENOMEM; @@ -1934,13 +1938,17 @@ static int arm_smmu_domain_get_attr(struct iommu_domain *domain, { struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); - if (domain->type != IOMMU_DOMAIN_UNMANAGED) - return -EINVAL; - switch (attr) { case DOMAIN_ATTR_NESTING: + if (domain->type != IOMMU_DOMAIN_UNMANAGED) + return -EINVAL; *(int *)data = (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED); return 0; + case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE: + if (domain->type != IOMMU_DOMAIN_DMA) + return -EINVAL; + *(int *)data = smmu_domain->non_strict; + return 0; default: return -ENODEV; } @@ -1952,13 +1960,15 @@ static int arm_smmu_domain_set_attr(struct iommu_domain *domain, int ret = 0; struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); - if (domain->type != IOMMU_DOMAIN_UNMANAGED) - return -EINVAL; - mutex_lock(&smmu_domain->init_mutex); switch (attr) { case DOMAIN_ATTR_NESTING: + if (domain->type != IOMMU_DOMAIN_UNMANAGED) { + ret = -EINVAL; + goto out_unlock; + } + if (smmu_domain->smmu) { ret = -EPERM; goto out_unlock; @@ -1969,6 +1979,14 @@ static int arm_smmu_domain_set_attr(struct iommu_domain *domain, else smmu_domain->stage = ARM_SMMU_DOMAIN_S1; + break; + case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE: + if (domain->type != IOMMU_DOMAIN_DMA) { + ret = -EINVAL; + goto out_unlock; + } + + smmu_domain->non_strict = *(int *)data; break; default: ret = -ENODEV;