This series is to replace the previous EMEDIUMTYPE patch in a VFIO series:
https://lore.kernel.org/kvm/[email protected]/
The purpose is to regulate all existing ->attach_dev callback functions to
use EINVAL exclusively for an incompatibility error between a device and a
domain. This allows VFIO and IOMMUFD to detect such a soft error, and then
try a different domain with the same device.
Among all the patches, the first two are preparatory changes. And then one
patch to update kdocs and another three patches for the enforcement effort.
Although it might be ideal to merge the previous VFIO series together with
this series, given the number of new changes, the review in the IOMMU list
might need a couple of rounds to finalize. Also, considering that v6.0 is
at rc5 now, perhaps we could merge this IOMMU series and the VFIO one in
different cycles to avoid merge conflicts. If there's less concern for it,
I can respin the finalized version of this series with the previous VFIO
one to merge together into the VFIO tree.
This series is also available on Github:
https://github.com/nicolinc/iommufd/commits/iommu_attach_dev-v4
Changelog
v4:
* Refined kdocs with Kevin's input
* Fixed an EINVAL conversion in the intel_iommu driver
* Added missing error-out routines in the msm_iommu driver
* Added a missing EINVAL conversion in the virtio-iommu driver
* Updated commit message and added "Reviewed-by" from Kevin to the last patch
v3: https://lore.kernel.org/linux-iommu/[email protected]/
* Added "Reviewed-by" from Vasant to the AMD patch
* Dropped all unnecessary errno enforcement patches
* Updated kdocs and brought back the kdocs for the helpers
* Added a separate patch to propagate "ret" for potential EINVALs
* Converted to ENODEV those existing EINVAL places that are device-specific
v2: https://lore.kernel.org/linux-iommu/[email protected]/
* Fixed kdocs format
* Grouped with the virtio patch from Jean (with a small change)
* Separated previous ENODEV and EINVAL changes to per-driver ones
* Redone some of the changes to have explicit return values in the
->attach_dev() callback functions or their direct sub-functions.
v1: https://lore.kernel.org/linux-iommu/[email protected]/
Thanks!
Nicolin Chen (6):
iommu/msm: Fix error-out routine in msm_iommu_attach_dev()
iommu/amd: Drop unnecessary checks in amd_iommu_attach_device()
iommu: Add return value rules to attach_dev op and APIs
iommu: Regulate EINVAL in ->attach_dev callback functions
iommu: Use EINVAL for incompatible device/domain in ->attach_dev
iommu: Propagate return value in ->attach_dev callback functions
drivers/iommu/amd/iommu.c | 12 +----
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 +---
drivers/iommu/arm/arm-smmu/arm-smmu.c | 3 --
drivers/iommu/arm/arm-smmu/qcom_iommu.c | 7 +--
drivers/iommu/fsl_pamu.c | 2 +-
drivers/iommu/fsl_pamu_domain.c | 4 +-
drivers/iommu/intel/iommu.c | 10 ++--
drivers/iommu/intel/pasid.c | 6 ++-
drivers/iommu/iommu.c | 22 ++++++++
drivers/iommu/ipmmu-vmsa.c | 2 -
drivers/iommu/msm_iommu.c | 59 +++++++++++----------
drivers/iommu/mtk_iommu.c | 4 +-
drivers/iommu/omap-iommu.c | 6 +--
drivers/iommu/sprd-iommu.c | 4 +-
drivers/iommu/tegra-gart.c | 2 +-
drivers/iommu/virtio-iommu.c | 7 ++-
include/linux/iommu.h | 12 +++++
17 files changed, 90 insertions(+), 83 deletions(-)
--
2.17.1
Cases like VFIO wish to attach a device to an existing domain that was
not allocated specifically from the device. This raises a condition
where the IOMMU driver can fail the domain attach because the domain and
device are incompatible with each other.
This is a soft failure that can be resolved by using a different domain.
Provide a dedicated errno EINVAL from the IOMMU driver during attach that
the reason why the attach failed is because of domain incompatibility.
VFIO can use this to know that the attach is a soft failure and it should
continue searching. Otherwise, the attach will be a hard failure and VFIO
will return the code to userspace.
Update kdocs to add rules of return value to the attach_dev op and APIs.
Suggested-by: Jason Gunthorpe <[email protected]>
Signed-off-by: Nicolin Chen <[email protected]>
---
drivers/iommu/iommu.c | 22 ++++++++++++++++++++++
include/linux/iommu.h | 12 ++++++++++++
2 files changed, 34 insertions(+)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 3a808146b50f..1d1e32aeaae6 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1975,6 +1975,17 @@ static int __iommu_attach_device(struct iommu_domain *domain,
return ret;
}
+/**
+ * iommu_attach_device - Attach a device to an IOMMU domain
+ * @domain: IOMMU domain to attach
+ * @dev: Device that will be attached
+ *
+ * Returns 0 on success and error code on failure
+ *
+ * Note that EINVAL may be returned as a soft failure if the domain and device
+ * are incompatible due to some previous configuration of the domain, in which
+ * case attaching the same device to a different domain may succeed.
+ */
int iommu_attach_device(struct iommu_domain *domain, struct device *dev)
{
struct iommu_group *group;
@@ -2101,6 +2112,17 @@ static int __iommu_attach_group(struct iommu_domain *domain,
return ret;
}
+/**
+ * iommu_attach_group - Attach an IOMMU group to an IOMMU domain
+ * @domain: IOMMU domain to attach
+ * @group: IOMMU group that will be attached
+ *
+ * Returns 0 on success and error code on failure
+ *
+ * Note that EINVAL may be returned as a soft failure if the domain and group
+ * are incompatible due to some previous configuration of the domain, in which
+ * case attaching the same group to a different domain may succeed.
+ */
int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
{
int ret;
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index ea30f00dc145..13a33b04e867 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -266,6 +266,18 @@ struct iommu_ops {
/**
* struct iommu_domain_ops - domain specific operations
* @attach_dev: attach an iommu domain to a device
+ * Return:
+ * * 0 - success
+ * * EINVAL - can indicate that device and domain are incompatible due to
+ * some previous configuration of the domain, in which case the
+ * driver shouldn't log an error, since it is legitimate for a
+ * caller to test reuse of existing domains. Otherwise, it may
+ * still represent some other fundamental problem
+ * * ENOMEM - out of memory
+ * * ENOSPC - non-ENOMEM type of resource allocation failures
+ * * EBUSY - device is attached to a domain and cannot be changed
+ * * ENODEV - device specific errors, not able to be attached
+ * * <others> - treated as ENODEV by the caller. Use is discouraged
* @detach_dev: detach an iommu domain from a device
* @map: map a physically contiguous memory region to an iommu domain
* @map_pages: map a physically contiguous set of pages of the same size to
--
2.17.1
The same checks are done in amd_iommu_probe_device(). If any of them fails
there, then the device won't get a group, so there's no way for it to even
reach amd_iommu_attach_device anymore.
Suggested-by: Robin Murphy <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Suravee Suthikulpanit <[email protected]>
Reviewed-by: Vasant Hegde <[email protected]>
Signed-off-by: Nicolin Chen <[email protected]>
---
drivers/iommu/amd/iommu.c | 12 ++----------
1 file changed, 2 insertions(+), 10 deletions(-)
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 828672a46a3d..930d9946b9f7 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2135,21 +2135,13 @@ static void amd_iommu_detach_device(struct iommu_domain *dom,
static int amd_iommu_attach_device(struct iommu_domain *dom,
struct device *dev)
{
+ struct iommu_dev_data *dev_data = dev_iommu_priv_get(dev);
struct protection_domain *domain = to_pdomain(dom);
- struct iommu_dev_data *dev_data;
- struct amd_iommu *iommu;
+ struct amd_iommu *iommu = rlookup_amd_iommu(dev);
int ret;
- if (!check_device(dev))
- return -EINVAL;
-
- dev_data = dev_iommu_priv_get(dev);
dev_data->defer_attach = false;
- iommu = rlookup_amd_iommu(dev);
- if (!iommu)
- return -EINVAL;
-
if (dev_data->domain)
detach_device(dev);
--
2.17.1
The mtk_iommu and virtio drivers have places in the ->attach_dev callback
functions that return hardcode errnos instead of the returned values, but
callers of these ->attach_dv callback functions may care. Propagate them
directly without the extra conversions.
Reviewed-by: Kevin Tian <[email protected]>
Signed-off-by: Nicolin Chen <[email protected]>
---
drivers/iommu/mtk_iommu.c | 2 +-
drivers/iommu/virtio-iommu.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index be1a7d1cc630..c30dc8f81778 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -666,7 +666,7 @@ static int mtk_iommu_attach_device(struct iommu_domain *domain,
ret = mtk_iommu_domain_finalise(dom, frstdata, region_id);
if (ret) {
mutex_unlock(&dom->mutex);
- return -ENODEV;
+ return ret;
}
dom->bank = &data->bank[bankid];
}
diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 87128266b6e3..35de7b433b17 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -696,7 +696,7 @@ static int viommu_domain_finalise(struct viommu_endpoint *vdev,
if (ret) {
ida_free(&viommu->domain_ids, vdomain->id);
vdomain->viommu = NULL;
- return -EOPNOTSUPP;
+ return ret;
}
}
--
2.17.1
Following the new rules in include/linux/iommu.h kdocs, update all drivers
->attach_dev callback functions to return EINVAL in the failure paths that
are related to domain incompatibility.
Also, drop adjacent error prints to prevent a kernel log spam.
Signed-off-by: Nicolin Chen <[email protected]>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 +----------
drivers/iommu/arm/arm-smmu/arm-smmu.c | 3 ---
drivers/iommu/arm/arm-smmu/qcom_iommu.c | 7 +------
drivers/iommu/intel/iommu.c | 10 +++-------
drivers/iommu/ipmmu-vmsa.c | 2 --
drivers/iommu/omap-iommu.c | 2 +-
drivers/iommu/sprd-iommu.c | 4 +---
drivers/iommu/tegra-gart.c | 2 +-
drivers/iommu/virtio-iommu.c | 3 +--
9 files changed, 9 insertions(+), 35 deletions(-)
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 d32b02336411..f96f8aad8280 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2429,23 +2429,14 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
goto out_unlock;
}
} else if (smmu_domain->smmu != smmu) {
- dev_err(dev,
- "cannot attach to SMMU %s (upstream of %s)\n",
- dev_name(smmu_domain->smmu->dev),
- dev_name(smmu->dev));
- ret = -ENXIO;
+ ret = -EINVAL;
goto out_unlock;
} else if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1 &&
master->ssid_bits != smmu_domain->s1_cfg.s1cdmax) {
- dev_err(dev,
- "cannot attach to incompatible domain (%u SSID bits != %u)\n",
- smmu_domain->s1_cfg.s1cdmax, master->ssid_bits);
ret = -EINVAL;
goto out_unlock;
} else if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1 &&
smmu_domain->stall_enabled != master->stall_enabled) {
- dev_err(dev, "cannot attach to stall-%s domain\n",
- smmu_domain->stall_enabled ? "enabled" : "disabled");
ret = -EINVAL;
goto out_unlock;
}
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index dfa82df00342..dbd12da31707 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -1167,9 +1167,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
* different SMMUs.
*/
if (smmu_domain->smmu != smmu) {
- dev_err(dev,
- "cannot attach to SMMU %s whilst already attached to domain on SMMU %s\n",
- dev_name(smmu_domain->smmu->dev), dev_name(smmu->dev));
ret = -EINVAL;
goto rpm_put;
}
diff --git a/drivers/iommu/arm/arm-smmu/qcom_iommu.c b/drivers/iommu/arm/arm-smmu/qcom_iommu.c
index 17235116d3bb..37c5ddc212c1 100644
--- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c
+++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c
@@ -381,13 +381,8 @@ static int qcom_iommu_attach_dev(struct iommu_domain *domain, struct device *dev
* Sanity check the domain. We don't support domains across
* different IOMMUs.
*/
- if (qcom_domain->iommu != qcom_iommu) {
- dev_err(dev, "cannot attach to IOMMU %s while already "
- "attached to domain on IOMMU %s\n",
- dev_name(qcom_domain->iommu->dev),
- dev_name(qcom_iommu->dev));
+ if (qcom_domain->iommu != qcom_iommu)
return -EINVAL;
- }
return 0;
}
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 1f2cd43cf9bc..51ef42b1bd4e 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4158,19 +4158,15 @@ static int prepare_domain_attach_device(struct iommu_domain *domain,
return -ENODEV;
if (dmar_domain->force_snooping && !ecap_sc_support(iommu->ecap))
- return -EOPNOTSUPP;
+ return -EINVAL;
/* check if this iommu agaw is sufficient for max mapped address */
addr_width = agaw_to_width(iommu->agaw);
if (addr_width > cap_mgaw(iommu->cap))
addr_width = cap_mgaw(iommu->cap);
- if (dmar_domain->max_addr > (1LL << addr_width)) {
- dev_err(dev, "%s: iommu width (%d) is not "
- "sufficient for the mapped address (%llx)\n",
- __func__, addr_width, dmar_domain->max_addr);
- return -EFAULT;
- }
+ if (dmar_domain->max_addr > (1LL << addr_width))
+ return -EINVAL;
dmar_domain->gaw = addr_width;
/*
diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
index 1d42084d0276..f5217a4cb9b3 100644
--- a/drivers/iommu/ipmmu-vmsa.c
+++ b/drivers/iommu/ipmmu-vmsa.c
@@ -628,8 +628,6 @@ static int ipmmu_attach_device(struct iommu_domain *io_domain,
* Something is wrong, we can't attach two devices using
* different IOMMUs to the same domain.
*/
- dev_err(dev, "Can't attach IPMMU %s to domain on IPMMU %s\n",
- dev_name(mmu->dev), dev_name(domain->mmu->dev));
ret = -EINVAL;
} else
dev_info(dev, "Reusing IPMMU context %u\n", domain->context_id);
diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index 447e40d55918..be12f49140c7 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -1472,7 +1472,7 @@ omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
/* only a single client device can be attached to a domain */
if (omap_domain->dev) {
dev_err(dev, "iommu domain is already attached\n");
- ret = -EBUSY;
+ ret = -EINVAL;
goto out;
}
diff --git a/drivers/iommu/sprd-iommu.c b/drivers/iommu/sprd-iommu.c
index 511959c8a14d..945576039c9e 100644
--- a/drivers/iommu/sprd-iommu.c
+++ b/drivers/iommu/sprd-iommu.c
@@ -237,10 +237,8 @@ static int sprd_iommu_attach_device(struct iommu_domain *domain,
struct sprd_iommu_domain *dom = to_sprd_domain(domain);
size_t pgt_size = sprd_iommu_pgt_size(domain);
- if (dom->sdev) {
- pr_err("There's already a device attached to this domain.\n");
+ if (dom->sdev)
return -EINVAL;
- }
dom->pgt_va = dma_alloc_coherent(sdev->dev, pgt_size, &dom->pgt_pa, GFP_KERNEL);
if (!dom->pgt_va)
diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
index e5ca3cf1a949..ed53279d1106 100644
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c
@@ -112,7 +112,7 @@ static int gart_iommu_attach_dev(struct iommu_domain *domain,
spin_lock(&gart->dom_lock);
if (gart->active_domain && gart->active_domain != domain) {
- ret = -EBUSY;
+ ret = -EINVAL;
} else if (dev_iommu_priv_get(dev) != domain) {
dev_iommu_priv_set(dev, domain);
gart->active_domain = domain;
diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 4c652773fd6c..87128266b6e3 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -733,8 +733,7 @@ static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev)
*/
ret = viommu_domain_finalise(vdev, domain);
} else if (vdomain->viommu != vdev->viommu) {
- dev_err(dev, "cannot attach to foreign vIOMMU\n");
- ret = -EXDEV;
+ ret = -EINVAL;
}
mutex_unlock(&vdomain->mutex);
--
2.17.1
On Wed, Sep 21, 2022 at 01:22:31AM -0700, Nicolin Chen wrote:
> This series is to replace the previous EMEDIUMTYPE patch in a VFIO series:
> https://lore.kernel.org/kvm/[email protected]/
>
> The purpose is to regulate all existing ->attach_dev callback functions to
> use EINVAL exclusively for an incompatibility error between a device and a
> domain. This allows VFIO and IOMMUFD to detect such a soft error, and then
> try a different domain with the same device.
[...]
> drivers/iommu/amd/iommu.c | 12 +----
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 +---
> drivers/iommu/arm/arm-smmu/arm-smmu.c | 3 --
> drivers/iommu/arm/arm-smmu/qcom_iommu.c | 7 +--
> drivers/iommu/fsl_pamu.c | 2 +-
> drivers/iommu/fsl_pamu_domain.c | 4 +-
> drivers/iommu/intel/iommu.c | 10 ++--
> drivers/iommu/intel/pasid.c | 6 ++-
> drivers/iommu/iommu.c | 22 ++++++++
> drivers/iommu/ipmmu-vmsa.c | 2 -
> drivers/iommu/msm_iommu.c | 59 +++++++++++----------
> drivers/iommu/mtk_iommu.c | 4 +-
> drivers/iommu/omap-iommu.c | 6 +--
> drivers/iommu/sprd-iommu.c | 4 +-
> drivers/iommu/tegra-gart.c | 2 +-
> drivers/iommu/virtio-iommu.c | 7 ++-
For virtio-iommu:
Reviewed-by: Jean-Philippe Brucker <[email protected]>
> include/linux/iommu.h | 12 +++++
> 17 files changed, 90 insertions(+), 83 deletions(-)
>
> --
> 2.17.1
>
On 9/21/22 4:23 PM, Nicolin Chen wrote:
> Cases like VFIO wish to attach a device to an existing domain that was
> not allocated specifically from the device. This raises a condition
> where the IOMMU driver can fail the domain attach because the domain and
> device are incompatible with each other.
>
> This is a soft failure that can be resolved by using a different domain.
>
> Provide a dedicated errno EINVAL from the IOMMU driver during attach that
> the reason why the attach failed is because of domain incompatibility.
>
> VFIO can use this to know that the attach is a soft failure and it should
> continue searching. Otherwise, the attach will be a hard failure and VFIO
> will return the code to userspace.
>
> Update kdocs to add rules of return value to the attach_dev op and APIs.
>
> Suggested-by: Jason Gunthorpe<[email protected]>
> Signed-off-by: Nicolin Chen<[email protected]>
> ---
> drivers/iommu/iommu.c | 22 ++++++++++++++++++++++
> include/linux/iommu.h | 12 ++++++++++++
> 2 files changed, 34 insertions(+)
>
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index 3a808146b50f..1d1e32aeaae6 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -1975,6 +1975,17 @@ static int __iommu_attach_device(struct iommu_domain *domain,
> return ret;
> }
>
> +/**
> + * iommu_attach_device - Attach a device to an IOMMU domain
Normally we say "attach an iommu domain to a device/group ...".
Best regards,
baolu
On 9/21/22 4:23 PM, Nicolin Chen wrote:
> Following the new rules in include/linux/iommu.h kdocs, update all drivers
> ->attach_dev callback functions to return EINVAL in the failure paths that
> are related to domain incompatibility.
>
> Also, drop adjacent error prints to prevent a kernel log spam.
>
> Signed-off-by: Nicolin Chen <[email protected]>
> ---
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 +----------
> drivers/iommu/arm/arm-smmu/arm-smmu.c | 3 ---
> drivers/iommu/arm/arm-smmu/qcom_iommu.c | 7 +------
> drivers/iommu/intel/iommu.c | 10 +++-------
> drivers/iommu/ipmmu-vmsa.c | 2 --
> drivers/iommu/omap-iommu.c | 2 +-
> drivers/iommu/sprd-iommu.c | 4 +---
> drivers/iommu/tegra-gart.c | 2 +-
> drivers/iommu/virtio-iommu.c | 3 +--
> 9 files changed, 9 insertions(+), 35 deletions(-)
>
> 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 d32b02336411..f96f8aad8280 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -2429,23 +2429,14 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
> goto out_unlock;
> }
> } else if (smmu_domain->smmu != smmu) {
> - dev_err(dev,
> - "cannot attach to SMMU %s (upstream of %s)\n",
> - dev_name(smmu_domain->smmu->dev),
> - dev_name(smmu->dev));
> - ret = -ENXIO;
> + ret = -EINVAL;
> goto out_unlock;
> } else if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1 &&
> master->ssid_bits != smmu_domain->s1_cfg.s1cdmax) {
> - dev_err(dev,
> - "cannot attach to incompatible domain (%u SSID bits != %u)\n",
> - smmu_domain->s1_cfg.s1cdmax, master->ssid_bits);
> ret = -EINVAL;
> goto out_unlock;
> } else if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1 &&
> smmu_domain->stall_enabled != master->stall_enabled) {
> - dev_err(dev, "cannot attach to stall-%s domain\n",
> - smmu_domain->stall_enabled ? "enabled" : "disabled");
> ret = -EINVAL;
> goto out_unlock;
> }
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> index dfa82df00342..dbd12da31707 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> @@ -1167,9 +1167,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
> * different SMMUs.
> */
> if (smmu_domain->smmu != smmu) {
> - dev_err(dev,
> - "cannot attach to SMMU %s whilst already attached to domain on SMMU %s\n",
> - dev_name(smmu_domain->smmu->dev), dev_name(smmu->dev));
> ret = -EINVAL;
> goto rpm_put;
> }
> diff --git a/drivers/iommu/arm/arm-smmu/qcom_iommu.c b/drivers/iommu/arm/arm-smmu/qcom_iommu.c
> index 17235116d3bb..37c5ddc212c1 100644
> --- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c
> +++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c
> @@ -381,13 +381,8 @@ static int qcom_iommu_attach_dev(struct iommu_domain *domain, struct device *dev
> * Sanity check the domain. We don't support domains across
> * different IOMMUs.
> */
> - if (qcom_domain->iommu != qcom_iommu) {
> - dev_err(dev, "cannot attach to IOMMU %s while already "
> - "attached to domain on IOMMU %s\n",
> - dev_name(qcom_domain->iommu->dev),
> - dev_name(qcom_iommu->dev));
> + if (qcom_domain->iommu != qcom_iommu)
> return -EINVAL;
> - }
>
> return 0;
> }
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index 1f2cd43cf9bc..51ef42b1bd4e 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -4158,19 +4158,15 @@ static int prepare_domain_attach_device(struct iommu_domain *domain,
> return -ENODEV;
>
> if (dmar_domain->force_snooping && !ecap_sc_support(iommu->ecap))
> - return -EOPNOTSUPP;
> + return -EINVAL;
>
> /* check if this iommu agaw is sufficient for max mapped address */
> addr_width = agaw_to_width(iommu->agaw);
> if (addr_width > cap_mgaw(iommu->cap))
> addr_width = cap_mgaw(iommu->cap);
>
> - if (dmar_domain->max_addr > (1LL << addr_width)) {
> - dev_err(dev, "%s: iommu width (%d) is not "
> - "sufficient for the mapped address (%llx)\n",
> - __func__, addr_width, dmar_domain->max_addr);
> - return -EFAULT;
> - }
> + if (dmar_domain->max_addr > (1LL << addr_width))
> + return -EINVAL;
> dmar_domain->gaw = addr_width;
>
> /*
> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> index 1d42084d0276..f5217a4cb9b3 100644
> --- a/drivers/iommu/ipmmu-vmsa.c
> +++ b/drivers/iommu/ipmmu-vmsa.c
> @@ -628,8 +628,6 @@ static int ipmmu_attach_device(struct iommu_domain *io_domain,
> * Something is wrong, we can't attach two devices using
> * different IOMMUs to the same domain.
> */
> - dev_err(dev, "Can't attach IPMMU %s to domain on IPMMU %s\n",
> - dev_name(mmu->dev), dev_name(domain->mmu->dev));
> ret = -EINVAL;
> } else
> dev_info(dev, "Reusing IPMMU context %u\n", domain->context_id);
> diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
> index 447e40d55918..be12f49140c7 100644
> --- a/drivers/iommu/omap-iommu.c
> +++ b/drivers/iommu/omap-iommu.c
> @@ -1472,7 +1472,7 @@ omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
> /* only a single client device can be attached to a domain */
> if (omap_domain->dev) {
> dev_err(dev, "iommu domain is already attached\n");
> - ret = -EBUSY;
> + ret = -EINVAL;
> goto out;
> }
>
> diff --git a/drivers/iommu/sprd-iommu.c b/drivers/iommu/sprd-iommu.c
> index 511959c8a14d..945576039c9e 100644
> --- a/drivers/iommu/sprd-iommu.c
> +++ b/drivers/iommu/sprd-iommu.c
> @@ -237,10 +237,8 @@ static int sprd_iommu_attach_device(struct iommu_domain *domain,
> struct sprd_iommu_domain *dom = to_sprd_domain(domain);
> size_t pgt_size = sprd_iommu_pgt_size(domain);
>
> - if (dom->sdev) {
> - pr_err("There's already a device attached to this domain.\n");
> + if (dom->sdev)
> return -EINVAL;
> - }
>
> dom->pgt_va = dma_alloc_coherent(sdev->dev, pgt_size, &dom->pgt_pa, GFP_KERNEL);
> if (!dom->pgt_va)
> diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
> index e5ca3cf1a949..ed53279d1106 100644
> --- a/drivers/iommu/tegra-gart.c
> +++ b/drivers/iommu/tegra-gart.c
> @@ -112,7 +112,7 @@ static int gart_iommu_attach_dev(struct iommu_domain *domain,
> spin_lock(&gart->dom_lock);
>
> if (gart->active_domain && gart->active_domain != domain) {
> - ret = -EBUSY;
> + ret = -EINVAL;
> } else if (dev_iommu_priv_get(dev) != domain) {
> dev_iommu_priv_set(dev, domain);
> gart->active_domain = domain;
> diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
> index 4c652773fd6c..87128266b6e3 100644
> --- a/drivers/iommu/virtio-iommu.c
> +++ b/drivers/iommu/virtio-iommu.c
> @@ -733,8 +733,7 @@ static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev)
> */
> ret = viommu_domain_finalise(vdev, domain);
> } else if (vdomain->viommu != vdev->viommu) {
> - dev_err(dev, "cannot attach to foreign vIOMMU\n");
> - ret = -EXDEV;
> + ret = -EINVAL;
> }
> mutex_unlock(&vdomain->mutex);
>
For iommu/vt-d changes:
Reviewed-by: Lu Baolu <[email protected]>
Best regards,
baolu
On Thu, Sep 22, 2022 at 10:02:42AM +0800, Baolu Lu wrote:
> > +/**
> > + * iommu_attach_device - Attach a device to an IOMMU domain
>
> Normally we say "attach an iommu domain to a device/group ...".
OK. I can fix it in the next respin.
And I'll add your Reviewed-by in the other two patches too.
Thanks!
Nic
> From: Nicolin Chen <[email protected]>
> Sent: Wednesday, September 21, 2022 4:23 PM
>
>
> +/**
> + * iommu_attach_device - Attach a device to an IOMMU domain
> + * @domain: IOMMU domain to attach
> + * @dev: Device that will be attached
> + *
> + * Returns 0 on success and error code on failure
> + *
> + * Note that EINVAL may be returned as a soft failure if the domain and
> device
> + * are incompatible due to some previous configuration of the domain, in
> which
> + * case attaching the same device to a different domain may succeed.
Revise a bit:
* Note that EINVAL can be treated as a soft failure, indicating
* that certain configuration of the domain is incompatible with
* the device. In this case attaching a different domain to the
* device may succeed.
Apart from that:
Reviewed-by: Kevin Tian <[email protected]>
> From: Nicolin Chen <[email protected]>
> Sent: Wednesday, September 21, 2022 4:24 PM
>
> Following the new rules in include/linux/iommu.h kdocs, update all drivers
> ->attach_dev callback functions to return EINVAL in the failure paths that
> are related to domain incompatibility.
>
> Also, drop adjacent error prints to prevent a kernel log spam.
>
> Signed-off-by: Nicolin Chen <[email protected]>
Reviewed-by: Kevin Tian <[email protected]>
On Thu, Sep 22, 2022 at 08:17:03AM +0000, Tian, Kevin wrote:
> External email: Use caution opening links or attachments
>
>
> > From: Nicolin Chen <[email protected]>
> > Sent: Wednesday, September 21, 2022 4:23 PM
> >
> >
> > +/**
> > + * iommu_attach_device - Attach a device to an IOMMU domain
> > + * @domain: IOMMU domain to attach
> > + * @dev: Device that will be attached
> > + *
> > + * Returns 0 on success and error code on failure
> > + *
> > + * Note that EINVAL may be returned as a soft failure if the domain and
> > device
> > + * are incompatible due to some previous configuration of the domain, in
> > which
> > + * case attaching the same device to a different domain may succeed.
>
> Revise a bit:
>
> * Note that EINVAL can be treated as a soft failure, indicating
> * that certain configuration of the domain is incompatible with
> * the device. In this case attaching a different domain to the
> * device may succeed.
Done. And added all your "Reviewed-by" too. Thanks!