PCIe Process address space ID (PASID) is used to tag DMA traffic, it
provides finer grained isolation than requester ID (RID).
For each RID, 0 is as a special PASID for the legacy DMA (without
PASID), thus RID_PASID. This is universal across all architectures,
therefore warranted to be declared in the common header.
Noting that VT-d could support none-zero RID_PASID, but currently not
used.
By having a common RID_PASID, we can avoid conflicts between different
use cases in the generic code. e.g. SVA and DMA API with PASIDs.
Signed-off-by: Jacob Pan <[email protected]>
---
v6:
- let SMMU code use the common RID_PASID macro
---
.../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 2 +-
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 10 ++++----
drivers/iommu/intel/iommu.c | 24 +++++++++----------
drivers/iommu/intel/pasid.c | 2 +-
drivers/iommu/intel/pasid.h | 1 -
include/linux/iommu.h | 1 +
6 files changed, 20 insertions(+), 20 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
index a5a63b1c947e..160b31e6239d 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
@@ -80,7 +80,7 @@ arm_smmu_share_asid(struct mm_struct *mm, u16 asid)
* be some overlap between use of both ASIDs, until we invalidate the
* TLB.
*/
- arm_smmu_write_ctx_desc(smmu_domain, 0, cd);
+ arm_smmu_write_ctx_desc(smmu_domain, IOMMU_DEF_RID_PASID, cd);
/* Invalidate TLB entries previously associated with that context */
arm_smmu_tlb_inv_asid(smmu, asid);
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 3fd83fb75722..9a6ea2d373c2 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -1053,7 +1053,7 @@ int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, int ssid,
/*
* This function handles the following cases:
*
- * (1) Install primary CD, for normal DMA traffic (SSID = 0).
+ * (1) Install primary CD, for normal DMA traffic (SSID = IOMMU_DEF_RID_PASID = 0).
* (2) Install a secondary CD, for SID+SSID traffic.
* (3) Update ASID of a CD. Atomically write the first 64 bits of the
* CD, then invalidate the old entry and mappings.
@@ -1869,7 +1869,7 @@ static void arm_smmu_tlb_inv_context(void *cookie)
cmd.tlbi.vmid = smmu_domain->s2_cfg.vmid;
arm_smmu_cmdq_issue_cmd_with_sync(smmu, &cmd);
}
- arm_smmu_atc_inv_domain(smmu_domain, 0, 0, 0);
+ arm_smmu_atc_inv_domain(smmu_domain, IOMMU_DEF_RID_PASID, 0, 0);
}
static void __arm_smmu_tlb_inv_range(struct arm_smmu_cmdq_ent *cmd,
@@ -1957,7 +1957,7 @@ static void arm_smmu_tlb_inv_range_domain(unsigned long iova, size_t size,
* Unfortunately, this can't be leaf-only since we may have
* zapped an entire table.
*/
- arm_smmu_atc_inv_domain(smmu_domain, 0, iova, size);
+ arm_smmu_atc_inv_domain(smmu_domain, IOMMU_DEF_RID_PASID, iova, size);
}
void arm_smmu_tlb_inv_range_asid(unsigned long iova, size_t size, int asid,
@@ -2131,7 +2131,7 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
* the master has been added to the devices list for this domain.
* This isn't an issue because the STE hasn't been installed yet.
*/
- ret = arm_smmu_write_ctx_desc(smmu_domain, 0, &cfg->cd);
+ ret = arm_smmu_write_ctx_desc(smmu_domain, IOMMU_DEF_RID_PASID, &cfg->cd);
if (ret)
goto out_free_cd_tables;
@@ -2317,7 +2317,7 @@ static void arm_smmu_enable_ats(struct arm_smmu_master *master)
pdev = to_pci_dev(master->dev);
atomic_inc(&smmu_domain->nr_ats_masters);
- arm_smmu_atc_inv_domain(smmu_domain, 0, 0, 0);
+ arm_smmu_atc_inv_domain(smmu_domain, IOMMU_DEF_RID_PASID, 0, 0);
if (pci_enable_ats(pdev, stu))
dev_err(master->dev, "Failed to enable ATS (STU %zu)\n", stu);
}
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index b871a6afd803..5b4ec7cfc1a4 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -877,7 +877,7 @@ void dmar_fault_dump_ptes(struct intel_iommu *iommu, u16 source_id,
}
/* For request-without-pasid, get the pasid from context entry */
if (intel_iommu_sm && pasid == IOMMU_PASID_INVALID)
- pasid = PASID_RID2PASID;
+ pasid = IOMMU_DEF_RID_PASID;
dir_index = pasid >> PASID_PDE_SHIFT;
pde = &dir[dir_index];
@@ -1457,7 +1457,7 @@ static void __iommu_flush_dev_iotlb(struct device_domain_info *info,
qdep = info->ats_qdep;
qi_flush_dev_iotlb(info->iommu, sid, info->pfsid,
qdep, addr, mask);
- quirk_extra_dev_tlb_flush(info, addr, mask, PASID_RID2PASID, qdep);
+ quirk_extra_dev_tlb_flush(info, addr, mask, IOMMU_DEF_RID_PASID, qdep);
}
static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
@@ -1492,7 +1492,7 @@ static void iommu_flush_iotlb_psi(struct intel_iommu *iommu,
ih = 1 << 6;
if (domain->use_first_level) {
- qi_flush_piotlb(iommu, did, PASID_RID2PASID, addr, pages, ih);
+ qi_flush_piotlb(iommu, did, IOMMU_DEF_RID_PASID, addr, pages, ih);
} else {
unsigned long bitmask = aligned_pages - 1;
@@ -1562,7 +1562,7 @@ static void intel_flush_iotlb_all(struct iommu_domain *domain)
u16 did = domain_id_iommu(dmar_domain, iommu);
if (dmar_domain->use_first_level)
- qi_flush_piotlb(iommu, did, PASID_RID2PASID, 0, -1, 0);
+ qi_flush_piotlb(iommu, did, IOMMU_DEF_RID_PASID, 0, -1, 0);
else
iommu->flush.flush_iotlb(iommu, did, 0, 0,
DMA_TLB_DSI_FLUSH);
@@ -1952,7 +1952,7 @@ static int domain_context_mapping_one(struct dmar_domain *domain,
context_pdts(pds);
/* Setup the RID_PASID field: */
- context_set_sm_rid2pasid(context, PASID_RID2PASID);
+ context_set_sm_rid2pasid(context, IOMMU_DEF_RID_PASID);
/*
* Setup the Device-TLB enable bit and Page request
@@ -2432,13 +2432,13 @@ static int dmar_domain_attach_device(struct dmar_domain *domain,
/* Setup the PASID entry for requests without PASID: */
if (hw_pass_through && domain_type_is_si(domain))
ret = intel_pasid_setup_pass_through(iommu, domain,
- dev, PASID_RID2PASID);
+ dev, IOMMU_DEF_RID_PASID);
else if (domain->use_first_level)
ret = domain_setup_first_level(iommu, domain, dev,
- PASID_RID2PASID);
+ IOMMU_DEF_RID_PASID);
else
ret = intel_pasid_setup_second_level(iommu, domain,
- dev, PASID_RID2PASID);
+ dev, IOMMU_DEF_RID_PASID);
if (ret) {
dev_err(dev, "Setup RID2PASID failed\n");
device_block_translation(dev);
@@ -3975,7 +3975,7 @@ static void dmar_remove_one_dev_info(struct device *dev)
if (!dev_is_real_dma_subdevice(info->dev)) {
if (dev_is_pci(info->dev) && sm_supported(iommu))
intel_pasid_tear_down_entry(iommu, info->dev,
- PASID_RID2PASID, false);
+ IOMMU_DEF_RID_PASID, false);
iommu_disable_pci_caps(info);
domain_context_clear(info);
@@ -4004,7 +4004,7 @@ static void device_block_translation(struct device *dev)
if (!dev_is_real_dma_subdevice(dev)) {
if (sm_supported(iommu))
intel_pasid_tear_down_entry(iommu, dev,
- PASID_RID2PASID, false);
+ IOMMU_DEF_RID_PASID, false);
else
domain_context_clear(info);
}
@@ -4339,7 +4339,7 @@ static void domain_set_force_snooping(struct dmar_domain *domain)
list_for_each_entry(info, &domain->devices, link)
intel_pasid_setup_page_snoop_control(info->iommu, info->dev,
- PASID_RID2PASID);
+ IOMMU_DEF_RID_PASID);
}
static bool intel_iommu_enforce_cache_coherency(struct iommu_domain *domain)
@@ -4994,7 +4994,7 @@ void quirk_extra_dev_tlb_flush(struct device_domain_info *info,
return;
sid = PCI_DEVID(info->bus, info->devfn);
- if (pasid == PASID_RID2PASID) {
+ if (pasid == IOMMU_DEF_RID_PASID) {
qi_flush_dev_iotlb(info->iommu, sid, info->pfsid,
qdep, address, mask);
} else {
diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
index c5d479770e12..e8c60af8591b 100644
--- a/drivers/iommu/intel/pasid.c
+++ b/drivers/iommu/intel/pasid.c
@@ -438,7 +438,7 @@ devtlb_invalidation_with_pasid(struct intel_iommu *iommu,
* SVA usage, device could do DMA with multiple PASIDs. It is more
* efficient to flush devTLB specific to the PASID.
*/
- if (pasid == PASID_RID2PASID)
+ if (pasid == IOMMU_DEF_RID_PASID)
qi_flush_dev_iotlb(iommu, sid, pfsid, qdep, 0, 64 - VTD_PAGE_SHIFT);
else
qi_flush_dev_iotlb_pasid(iommu, sid, pfsid, pasid, qdep, 0, 64 - VTD_PAGE_SHIFT);
diff --git a/drivers/iommu/intel/pasid.h b/drivers/iommu/intel/pasid.h
index d6b7d21244b1..027d30afaba6 100644
--- a/drivers/iommu/intel/pasid.h
+++ b/drivers/iommu/intel/pasid.h
@@ -10,7 +10,6 @@
#ifndef __INTEL_PASID_H
#define __INTEL_PASID_H
-#define PASID_RID2PASID 0x0
#define PASID_MIN 0x1
#define PASID_MAX 0x100000
#define PASID_PTE_MASK 0x3F
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index e8c9a7da1060..d8327f2b6fcc 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -190,6 +190,7 @@ enum iommu_dev_features {
IOMMU_DEV_FEAT_IOPF,
};
+#define IOMMU_DEF_RID_PASID (0U) /* Reserved for DMA w/o PASID */
#define IOMMU_PASID_INVALID (-1U)
typedef unsigned int ioasid_t;
--
2.25.1
On 5/20/23 4:32 AM, Jacob Pan wrote:
> PCIe Process address space ID (PASID) is used to tag DMA traffic, it
> provides finer grained isolation than requester ID (RID).
>
> For each RID, 0 is as a special PASID for the legacy DMA (without
> PASID), thus RID_PASID. This is universal across all architectures,
> therefore warranted to be declared in the common header.
> Noting that VT-d could support none-zero RID_PASID, but currently not
> used.
>
> By having a common RID_PASID, we can avoid conflicts between different
> use cases in the generic code. e.g. SVA and DMA API with PASIDs.
>
> Signed-off-by: Jacob Pan<[email protected]>
Reviewed-by: Lu Baolu <[email protected]>
Best regards,
baolu
Hi Jacob,
On Fri, May 19, 2023 at 01:32:20PM -0700, Jacob Pan wrote:
> PCIe Process address space ID (PASID) is used to tag DMA traffic, it
> provides finer grained isolation than requester ID (RID).
>
> For each RID, 0 is as a special PASID for the legacy DMA (without
> PASID), thus RID_PASID. This is universal across all architectures,
> therefore warranted to be declared in the common header.
> Noting that VT-d could support none-zero RID_PASID, but currently not
> used.
>
> By having a common RID_PASID, we can avoid conflicts between different
> use cases in the generic code. e.g. SVA and DMA API with PASIDs.
>
> Signed-off-by: Jacob Pan <[email protected]>
> ---
> v6:
> - let SMMU code use the common RID_PASID macro
> ---
> .../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 2 +-
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 10 ++++----
> drivers/iommu/intel/iommu.c | 24 +++++++++----------
> drivers/iommu/intel/pasid.c | 2 +-
> drivers/iommu/intel/pasid.h | 1 -
> include/linux/iommu.h | 1 +
> 6 files changed, 20 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> index a5a63b1c947e..160b31e6239d 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> @@ -80,7 +80,7 @@ arm_smmu_share_asid(struct mm_struct *mm, u16 asid)
> * be some overlap between use of both ASIDs, until we invalidate the
> * TLB.
> */
> - arm_smmu_write_ctx_desc(smmu_domain, 0, cd);
> + arm_smmu_write_ctx_desc(smmu_domain, IOMMU_DEF_RID_PASID, cd);
I agree with reserving 0 globally for non-PASID DMA, but could we call
this something more generic, like IOMMU_NO_PASID? The term "RID_PASID" is
specific to VT-d and "RID" to PCI, so it looks confusing here (this driver
also supports non-PCI). "NO_PASID" would be clearer to someone just trying
to follow this driver code.
Thanks,
Jean
Hi Jean,
On Tue, 23 May 2023 15:47:33 +0100, Jean-Philippe Brucker
<[email protected]> wrote:
> Hi Jacob,
>
> On Fri, May 19, 2023 at 01:32:20PM -0700, Jacob Pan wrote:
> > PCIe Process address space ID (PASID) is used to tag DMA traffic, it
> > provides finer grained isolation than requester ID (RID).
> >
> > For each RID, 0 is as a special PASID for the legacy DMA (without
> > PASID), thus RID_PASID. This is universal across all architectures,
> > therefore warranted to be declared in the common header.
> > Noting that VT-d could support none-zero RID_PASID, but currently not
> > used.
> >
> > By having a common RID_PASID, we can avoid conflicts between different
> > use cases in the generic code. e.g. SVA and DMA API with PASIDs.
> >
> > Signed-off-by: Jacob Pan <[email protected]>
> > ---
> > v6:
> > - let SMMU code use the common RID_PASID macro
> > ---
> > .../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 2 +-
> > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 10 ++++----
> > drivers/iommu/intel/iommu.c | 24 +++++++++----------
> > drivers/iommu/intel/pasid.c | 2 +-
> > drivers/iommu/intel/pasid.h | 1 -
> > include/linux/iommu.h | 1 +
> > 6 files changed, 20 insertions(+), 20 deletions(-)
> >
> > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> > b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c index
> > a5a63b1c947e..160b31e6239d 100644 ---
> > a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c +++
> > b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c @@ -80,7 +80,7 @@
> > arm_smmu_share_asid(struct mm_struct *mm, u16 asid)
> > * be some overlap between use of both ASIDs, until we
> > invalidate the
> > * TLB.
> > */
> > - arm_smmu_write_ctx_desc(smmu_domain, 0, cd);
> > + arm_smmu_write_ctx_desc(smmu_domain, IOMMU_DEF_RID_PASID, cd);
> >
>
> I agree with reserving 0 globally for non-PASID DMA, but could we call
> this something more generic, like IOMMU_NO_PASID? The term "RID_PASID" is
> specific to VT-d and "RID" to PCI, so it looks confusing here (this driver
> also supports non-PCI). "NO_PASID" would be clearer to someone just trying
> to follow this driver code.
>
Sounds good, it is for DMA w/o PASID.
Thanks,
Jacob
On Fri, May 19, 2023 at 01:32:20PM -0700, Jacob Pan wrote:
> PCIe Process address space ID (PASID) is used to tag DMA traffic, it
> provides finer grained isolation than requester ID (RID).
>
> For each RID, 0 is as a special PASID for the legacy DMA (without
> PASID), thus RID_PASID. This is universal across all architectures,
> therefore warranted to be declared in the common header.
> Noting that VT-d could support none-zero RID_PASID, but currently not
> used.
>
> By having a common RID_PASID, we can avoid conflicts between different
> use cases in the generic code. e.g. SVA and DMA API with PASIDs.
>
> Signed-off-by: Jacob Pan <[email protected]>
> ---
> v6:
> - let SMMU code use the common RID_PASID macro
> ---
> .../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 2 +-
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 10 ++++----
> drivers/iommu/intel/iommu.c | 24 +++++++++----------
> drivers/iommu/intel/pasid.c | 2 +-
> drivers/iommu/intel/pasid.h | 1 -
> include/linux/iommu.h | 1 +
> 6 files changed, 20 insertions(+), 20 deletions(-)
I tend to agree with Jean-Philippe's remarks on the name
This is the "untagged" DMA for environments that have optional tags.
Otherwise:
Reviewed-by: Jason Gunthorpe <[email protected]>
Jason