| Message ID | 20220913082448.31120-5-nicolinc@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iommu: Define EINVAL as device/domain incompatibility | expand |
Hi Nicolin, On Tue, Sep 13, 2022 at 01:24:47AM -0700, Nicolin Chen wrote: > Following the new rules in include/linux/iommu.h kdocs, update all drivers > ->attach_dev callback functions to return ENODEV error code for all device > specific errors. It particularly excludes EINVAL from being used for such > error cases. For the same purpose, also replace one EINVAL with ENOMEM in > mtk_iommu driver. > > Note that the virtio-iommu does a viommu_domain_map_identity() call, which > returns either 0 or ENOMEM at this moment. Change to "return ret" directly > to allow it to pass an EINVAL in the future. [...] > diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c > index 80151176ba12..874c01634d2b 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; I think in the future it will be too easy to forget about the constrained return value of attach() while modifying some other part of the driver, and let an external helper return EINVAL. So I'd rather not propagate ret from outside of viommu_domain_attach() and finalise(). For the same reason I do prefer this solution over EMEDIUMTYPE, because it's too tempting to use exotic errno when they seem appropriate instead of boring ENODEV and EINVAL. The alternative would be adding a special purpose code to linux/errno.h, similarly to EPROBE_DEFER, but that might be excessive. Since we can't guarantee that APIs like virtio or ida won't ever return EINVAL, we should set all return values: --- 8< --- From 7b16796cb78d11971236f98fd2d3cd73ca769827 Mon Sep 17 00:00:00 2001 From: Jean-Philippe Brucker <jean-philippe@linaro.org> Date: Tue, 13 Sep 2022 12:53:02 +0100 Subject: [PATCH] iommu/virtio: Constrain return value of viommu_attach_dev() Ensure viommu_attach_dev() only return errno values expected from the attach_dev() op. In particular, only return EINVAL when we're sure that the device is incompatible with the domain. Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> --- drivers/iommu/virtio-iommu.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 08eeafc9529f..582ff5a33b52 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -669,13 +669,13 @@ static int viommu_domain_finalise(struct viommu_endpoint *vdev, dev_err(vdev->dev, "granule 0x%lx larger than system page size 0x%lx\n", viommu_page_size, PAGE_SIZE); - return -EINVAL; + return -ENODEV; } ret = ida_alloc_range(&viommu->domain_ids, viommu->first_domain, viommu->last_domain, GFP_KERNEL); if (ret < 0) - return ret; + return -ENOMEM; vdomain->id = (unsigned int)ret; @@ -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 -ENODEV; } } @@ -734,7 +734,7 @@ 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); @@ -769,7 +769,7 @@ static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev) ret = viommu_send_req_sync(vdomain->viommu, &req, sizeof(req)); if (ret) - return ret; + return -ENODEV; } if (!vdomain->nr_endpoints) { @@ -779,7 +779,7 @@ static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev) */ ret = viommu_replay_mappings(vdomain); if (ret) - return ret; + return -ENODEV; } vdomain->nr_endpoints++;
Hi Jean, On Tue, Sep 13, 2022 at 01:27:03PM +0100, Jean-Philippe Brucker wrote: > External email: Use caution opening links or attachments > > > Hi Nicolin, > > On Tue, Sep 13, 2022 at 01:24:47AM -0700, Nicolin Chen wrote: > > Following the new rules in include/linux/iommu.h kdocs, update all drivers > > ->attach_dev callback functions to return ENODEV error code for all device > > specific errors. It particularly excludes EINVAL from being used for such > > error cases. For the same purpose, also replace one EINVAL with ENOMEM in > > mtk_iommu driver. > > > > Note that the virtio-iommu does a viommu_domain_map_identity() call, which > > returns either 0 or ENOMEM at this moment. Change to "return ret" directly > > to allow it to pass an EINVAL in the future. > [...] > > diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c > > index 80151176ba12..874c01634d2b 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; > > I think in the future it will be too easy to forget about the constrained > return value of attach() while modifying some other part of the driver, > and let an external helper return EINVAL. So I'd rather not propagate ret > from outside of viommu_domain_attach() and finalise(). > > For the same reason I do prefer this solution over EMEDIUMTYPE, because > it's too tempting to use exotic errno when they seem appropriate instead > of boring ENODEV and EINVAL. The alternative would be adding a special > purpose code to linux/errno.h, similarly to EPROBE_DEFER, but that might > be excessive. > > Since we can't guarantee that APIs like virtio or ida won't ever return > EINVAL, we should set all return values: Thanks for the inputs. Assuming your attached patch isn't officially sent, I will group it into my next version. Similarly, I will also double check other drivers, to make sure all of them have explicit return values, other than "ret".
On Tue, Sep 13, 2022 at 01:27:03PM +0100, Jean-Philippe Brucker wrote: > I think in the future it will be too easy to forget about the constrained > return value of attach() while modifying some other part of the driver, > and let an external helper return EINVAL. So I'd rather not propagate ret > from outside of viommu_domain_attach() and finalise(). Fortunately, if -EINVAL is wrongly returned it only creates an inefficiency, not a functional problem. So we do not need to be precise here. > Since we can't guarantee that APIs like virtio or ida won't ever return > EINVAL, we should set all return values: I dislike this alot, it squashes all return codes to try to optimize an obscure failure path :( Jason
On Wed, Sep 14, 2022 at 06:11:06AM -0300, Jason Gunthorpe wrote: > On Tue, Sep 13, 2022 at 01:27:03PM +0100, Jean-Philippe Brucker wrote: > > I think in the future it will be too easy to forget about the constrained > > return value of attach() while modifying some other part of the driver, > > and let an external helper return EINVAL. So I'd rather not propagate ret > > from outside of viommu_domain_attach() and finalise(). > > Fortunately, if -EINVAL is wrongly returned it only creates an > inefficiency, not a functional problem. So we do not need to be > precise here. Ah fair. In that case the attach_dev() documentation should indicate that EINVAL is a hint, so that callers don't rely on it (currently words "must" and "exclusively" indicate that returning EINVAL for anything other than device-domain incompatibility is unacceptable). The virtio-iommu implementation may well return EINVAL from the virtio stack or from the host response. Thanks, Jean > > > Since we can't guarantee that APIs like virtio or ida won't ever return > > EINVAL, we should set all return values: > > I dislike this alot, it squashes all return codes to try to optimize > an obscure failure path :( > > Jason
On Wed, Sep 14, 2022 at 10:49:42AM +0100, Jean-Philippe Brucker wrote: > External email: Use caution opening links or attachments > > > On Wed, Sep 14, 2022 at 06:11:06AM -0300, Jason Gunthorpe wrote: > > On Tue, Sep 13, 2022 at 01:27:03PM +0100, Jean-Philippe Brucker wrote: > > > I think in the future it will be too easy to forget about the constrained > > > return value of attach() while modifying some other part of the driver, > > > and let an external helper return EINVAL. So I'd rather not propagate ret > > > from outside of viommu_domain_attach() and finalise(). > > > > Fortunately, if -EINVAL is wrongly returned it only creates an > > inefficiency, not a functional problem. So we do not need to be > > precise here. > > Ah fair. In that case the attach_dev() documentation should indicate that > EINVAL is a hint, so that callers don't rely on it (currently words "must" > and "exclusively" indicate that returning EINVAL for anything other than > device-domain incompatibility is unacceptable). The virtio-iommu > implementation may well return EINVAL from the virtio stack or from the > host response. How about this? + * * EINVAL - mainly, device and domain are incompatible, or something went + * wrong with the domain. It's suggested to avoid kernel prints + * along with this errno. And it's better to convert any EINVAL + * returned from kAPIs to ENODEV if it is device-specific, or to + * some other reasonable errno being listed below > > > Since we can't guarantee that APIs like virtio or ida won't ever return > > > EINVAL, we should set all return values: > > > > I dislike this alot, it squashes all return codes to try to optimize > > an obscure failure path :( Hmm...should I revert all the driver changes back to this version?
On 2022-09-14 18:58, Nicolin Chen wrote: > On Wed, Sep 14, 2022 at 10:49:42AM +0100, Jean-Philippe Brucker wrote: >> External email: Use caution opening links or attachments >> >> >> On Wed, Sep 14, 2022 at 06:11:06AM -0300, Jason Gunthorpe wrote: >>> On Tue, Sep 13, 2022 at 01:27:03PM +0100, Jean-Philippe Brucker wrote: >>>> I think in the future it will be too easy to forget about the constrained >>>> return value of attach() while modifying some other part of the driver, >>>> and let an external helper return EINVAL. So I'd rather not propagate ret >>>> from outside of viommu_domain_attach() and finalise(). >>> >>> Fortunately, if -EINVAL is wrongly returned it only creates an >>> inefficiency, not a functional problem. So we do not need to be >>> precise here. >> >> Ah fair. In that case the attach_dev() documentation should indicate that >> EINVAL is a hint, so that callers don't rely on it (currently words "must" >> and "exclusively" indicate that returning EINVAL for anything other than >> device-domain incompatibility is unacceptable). The virtio-iommu >> implementation may well return EINVAL from the virtio stack or from the >> host response. > > How about this? > > + * * EINVAL - mainly, device and domain are incompatible, or something went > + * wrong with the domain. It's suggested to avoid kernel prints > + * along with this errno. And it's better to convert any EINVAL > + * returned from kAPIs to ENODEV if it is device-specific, or to > + * some other reasonable errno being listed below FWIW, I'd say something like: "The device and domain are incompatible. If this is due to some previous configuration of the domain, drivers should not log an error, since it is legitimate for callers to test reuse of an existing domain. Otherwise, it may still represent some fundamental problem." And then at the public interfaces state it from other angle: "The device and domain are incompatible. If the domain has already been used or configured in some way, attaching the same device to a different domain may be expected to succeed. Otherwise, it may still represent some fundamental problem." [ and to save another mail, I'm not sure copying the default comment for ENOSPC is all that helpful either - what is "space" for something that isn't a storage device? I'd guess limited hardware resources in some form, but in the IOMMU context, potential confusion with address space is maybe a little too close for comfort? ] >>>> Since we can't guarantee that APIs like virtio or ida won't ever return >>>> EINVAL, we should set all return values: >>> >>> I dislike this alot, it squashes all return codes to try to optimize >>> an obscure failure path :( > > Hmm...should I revert all the driver changes back to this version? Yeah, I don't think we need to go too mad here. Drivers shouldn't emit their *own* -EINVAL unless appropriate, but if it comes back from some external API then that implies something's gone unexpectedly wrong anyway - maybe it's a transient condition and a subsequent different attach might actually work out OK? We can't really say in general. Besides, if the driver sees an error which implies it's done something wrong itself, it probably shouldn't be trusted to try to reason about it further. The caller can handle any error as long as we set their expectations correctly. Thanks, Robin.
Hi Robin, On Wed, Sep 14, 2022 at 08:53:07PM +0100, Robin Murphy wrote: > External email: Use caution opening links or attachments > > > On 2022-09-14 18:58, Nicolin Chen wrote: > > On Wed, Sep 14, 2022 at 10:49:42AM +0100, Jean-Philippe Brucker wrote: > > > External email: Use caution opening links or attachments > > > > > > > > > On Wed, Sep 14, 2022 at 06:11:06AM -0300, Jason Gunthorpe wrote: > > > > On Tue, Sep 13, 2022 at 01:27:03PM +0100, Jean-Philippe Brucker wrote: > > > > > I think in the future it will be too easy to forget about the constrained > > > > > return value of attach() while modifying some other part of the driver, > > > > > and let an external helper return EINVAL. So I'd rather not propagate ret > > > > > from outside of viommu_domain_attach() and finalise(). > > > > > > > > Fortunately, if -EINVAL is wrongly returned it only creates an > > > > inefficiency, not a functional problem. So we do not need to be > > > > precise here. > > > > > > Ah fair. In that case the attach_dev() documentation should indicate that > > > EINVAL is a hint, so that callers don't rely on it (currently words "must" > > > and "exclusively" indicate that returning EINVAL for anything other than > > > device-domain incompatibility is unacceptable). The virtio-iommu > > > implementation may well return EINVAL from the virtio stack or from the > > > host response. > > > > How about this? > > > > + * * EINVAL - mainly, device and domain are incompatible, or something went > > + * wrong with the domain. It's suggested to avoid kernel prints > > + * along with this errno. And it's better to convert any EINVAL > > + * returned from kAPIs to ENODEV if it is device-specific, or to > > + * some other reasonable errno being listed below > > FWIW, I'd say something like: > > "The device and domain are incompatible. If this is due to some previous > configuration of the domain, drivers should not log an error, since it > is legitimate for callers to test reuse of an existing domain. > Otherwise, it may still represent some fundamental problem." OK. I will use this narrative. > And then at the public interfaces state it from other angle: > > "The device and domain are incompatible. If the domain has already been > used or configured in some way, attaching the same device to a different > domain may be expected to succeed. Otherwise, it may still represent > some fundamental problem." I assume this should go to kdocs of iommu_attach_device/group(). > [ and to save another mail, I'm not sure copying the default comment for > ENOSPC is all that helpful either - what is "space" for something that > isn't a storage device? I'd guess limited hardware resources in some > form, but in the IOMMU context, potential confusion with address space > is maybe a little too close for comfort? ] How about "non-ENOMEM type of resource allocation failure"? > > > > > Since we can't guarantee that APIs like virtio or ida won't ever return > > > > > EINVAL, we should set all return values: > > > > > > > > I dislike this alot, it squashes all return codes to try to optimize > > > > an obscure failure path :( > > > > Hmm...should I revert all the driver changes back to this version? > > Yeah, I don't think we need to go too mad here. Drivers shouldn't emit > their *own* -EINVAL unless appropriate, but if it comes back from some > external API then that implies something's gone unexpectedly wrong > anyway - maybe it's a transient condition and a subsequent different > attach might actually work out OK? We can't really say in general. OK. Then there's even no need to convert EINVAL to ENODEV. > Besides, if the driver sees an error which implies it's done something > wrong itself, it probably shouldn't be trusted to try to reason about it > further. The caller can handle any error as long as we set their > expectations correctly. Yea. As Jason remarked, a wrongly returned EINVAL would make things a bit inefficient: VFIO/IOMMUFD would keep trying attach_dev() with its existing domain list and a new domain but fail all of them. I will change things in v2 back to this 2-patch version, and maybe limit a bit further the changes in the first NODEV patch. Thanks! Nic
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..0186dfdf31fe 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2402,7 +2402,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) struct arm_smmu_master *master; if (!fwspec) - return -ENOENT; + return -ENODEV; master = dev_iommu_priv_get(dev); smmu = master->smmu; diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c index dfa82df00342..771dd161545c 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c @@ -1137,7 +1137,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) if (!fwspec || fwspec->ops != &arm_smmu_ops) { dev_err(dev, "cannot attach to SMMU, is it on the same bus?\n"); - return -ENXIO; + return -ENODEV; } /* @@ -1155,7 +1155,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) ret = arm_smmu_rpm_get(smmu); if (ret < 0) - return ret; + return -ENODEV; /* Ensure that the domain is finalised */ ret = arm_smmu_init_domain_context(domain, smmu, dev); diff --git a/drivers/iommu/arm/arm-smmu/qcom_iommu.c b/drivers/iommu/arm/arm-smmu/qcom_iommu.c index 17235116d3bb..49d40c80afd3 100644 --- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c +++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c @@ -367,7 +367,7 @@ static int qcom_iommu_attach_dev(struct iommu_domain *domain, struct device *dev if (!qcom_iommu) { dev_err(dev, "cannot attach to IOMMU, is it on the same bus?\n"); - return -ENXIO; + return -ENODEV; } /* Ensure that the domain is finalized */ diff --git a/drivers/iommu/fsl_pamu.c b/drivers/iommu/fsl_pamu.c index 0d03f837a5d4..021ab3f9e6d2 100644 --- a/drivers/iommu/fsl_pamu.c +++ b/drivers/iommu/fsl_pamu.c @@ -126,7 +126,7 @@ int pamu_disable_liodn(int liodn) ppaace = pamu_get_ppaace(liodn); if (!ppaace) { pr_debug("Invalid primary paace entry\n"); - return -ENOENT; + return -ENODEV; } set_bf(ppaace->addr_bitfields, PAACE_AF_V, PAACE_V_INVALID); @@ -194,7 +194,7 @@ int pamu_config_ppaace(int liodn, u32 omi, u32 stashid, int prot) ppaace = pamu_get_ppaace(liodn); if (!ppaace) - return -ENOENT; + return -ENODEV; /* window size is 2^(WSE+1) bytes */ set_bf(ppaace->addr_bitfields, PPAACE_AF_WSE, @@ -211,7 +211,7 @@ int pamu_config_ppaace(int liodn, u32 omi, u32 stashid, int prot) ppaace->op_encode.index_ot.omi = omi; } else if (~omi != 0) { pr_debug("bad operation mapping index: %d\n", omi); - return -EINVAL; + return -ENODEV; } /* configure stash id */ diff --git a/drivers/iommu/fsl_pamu_domain.c b/drivers/iommu/fsl_pamu_domain.c index 011f9ab7f743..b4a1c0f79c3e 100644 --- a/drivers/iommu/fsl_pamu_domain.c +++ b/drivers/iommu/fsl_pamu_domain.c @@ -258,7 +258,7 @@ static int fsl_pamu_attach_device(struct iommu_domain *domain, liodn = of_get_property(dev->of_node, "fsl,liodn", &len); if (!liodn) { pr_debug("missing fsl,liodn property at %pOF\n", dev->of_node); - return -EINVAL; + return -ENODEV; } spin_lock_irqsave(&dma_domain->domain_lock, flags); @@ -267,7 +267,7 @@ static int fsl_pamu_attach_device(struct iommu_domain *domain, if (liodn[i] >= PAACE_NUMBER_ENTRIES) { pr_debug("Invalid liodn %d, attach device failed for %pOF\n", liodn[i], dev->of_node); - ret = -EINVAL; + ret = -ENODEV; break; } diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c index c5e7e8b020a5..712c7f3960e5 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -102,7 +102,7 @@ int intel_pasid_alloc_table(struct device *dev) might_sleep(); info = dev_iommu_priv_get(dev); if (WARN_ON(!info || !dev_is_pci(dev) || info->pasid_table)) - return -EINVAL; + return -ENODEV; pasid_table = kzalloc(sizeof(*pasid_table), GFP_KERNEL); if (!pasid_table) diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c index 1d42084d0276..cb14abcfa43a 100644 --- a/drivers/iommu/ipmmu-vmsa.c +++ b/drivers/iommu/ipmmu-vmsa.c @@ -607,7 +607,7 @@ static int ipmmu_attach_device(struct iommu_domain *io_domain, if (!mmu) { dev_err(dev, "Cannot attach to IPMMU\n"); - return -ENXIO; + return -ENODEV; } mutex_lock(&domain->mutex); diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 7e363b1f24df..dcfe728a4526 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -562,10 +562,12 @@ static int mtk_iommu_config(struct mtk_iommu_data *data, struct device *dev, peri_mmuen = enable ? peri_mmuen_msk : 0; ret = regmap_update_bits(data->pericfg, PERICFG_IOMMU_1, peri_mmuen_msk, peri_mmuen); - if (ret) + if (ret) { dev_err(dev, "%s iommu(%s) inframaster 0x%x fail(%d).\n", enable ? "enable" : "disable", dev_name(data->dev), peri_mmuen_msk, ret); + ret = -ENODEV; + } } } return ret; @@ -607,7 +609,7 @@ static int mtk_iommu_domain_finalise(struct mtk_iommu_domain *dom, dom->iop = alloc_io_pgtable_ops(ARM_V7S, &dom->cfg, data); if (!dom->iop) { dev_err(data->dev, "Failed to alloc io pgtable\n"); - return -EINVAL; + return -ENOMEM; } /* Update our support page sizes bitmap */ @@ -655,7 +657,7 @@ static int mtk_iommu_attach_device(struct iommu_domain *domain, region_id = mtk_iommu_get_iova_region_id(dev, data->plat_data); if (region_id < 0) - return region_id; + return -ENODEV; bankid = mtk_iommu_get_bank_id(dev, data->plat_data); mutex_lock(&dom->mutex); @@ -678,6 +680,7 @@ static int mtk_iommu_attach_device(struct iommu_domain *domain, ret = pm_runtime_resume_and_get(m4udev); if (ret < 0) { dev_err(m4udev, "pm get fail(%d) in attach.\n", ret); + ret = -ENODEV; goto err_unlock; } diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c index d9cf2820c02e..447e40d55918 100644 --- a/drivers/iommu/omap-iommu.c +++ b/drivers/iommu/omap-iommu.c @@ -1414,7 +1414,7 @@ static int omap_iommu_attach_init(struct device *dev, odomain->num_iommus = omap_iommu_count(dev); if (!odomain->num_iommus) - return -EINVAL; + return -ENODEV; odomain->iommus = kcalloc(odomain->num_iommus, sizeof(*iommu), GFP_ATOMIC); @@ -1464,7 +1464,7 @@ omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev) if (!arch_data || !arch_data->iommu_dev) { dev_err(dev, "device doesn't have an associated iommu\n"); - return -EINVAL; + return -ENODEV; } spin_lock(&omap_domain->lock); diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c index ab57c4b8fade..de483b5532ed 100644 --- a/drivers/iommu/rockchip-iommu.c +++ b/drivers/iommu/rockchip-iommu.c @@ -1051,8 +1051,10 @@ static int rk_iommu_attach_device(struct iommu_domain *domain, return 0; ret = rk_iommu_enable(iommu); - if (ret) + if (ret) { rk_iommu_detach_device(iommu->domain, dev); + ret = -ENODEV; + } pm_runtime_put(iommu->dev); diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c index 2a8de975fe63..093c10db4cb4 100644 --- a/drivers/iommu/tegra-smmu.c +++ b/drivers/iommu/tegra-smmu.c @@ -487,7 +487,7 @@ static int tegra_smmu_attach_dev(struct iommu_domain *domain, int err; if (!fwspec) - return -ENOENT; + return -ENODEV; for (index = 0; index < fwspec->num_ids; index++) { err = tegra_smmu_as_prepare(smmu, as); diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 80151176ba12..874c01634d2b 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; } }
Following the new rules in include/linux/iommu.h kdocs, update all drivers ->attach_dev callback functions to return ENODEV error code for all device specific errors. It particularly excludes EINVAL from being used for such error cases. For the same purpose, also replace one EINVAL with ENOMEM in mtk_iommu driver. Note that the virtio-iommu does a viommu_domain_map_identity() call, which returns either 0 or ENOMEM at this moment. Change to "return ret" directly to allow it to pass an EINVAL in the future. Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 2 +- drivers/iommu/arm/arm-smmu/arm-smmu.c | 4 ++-- drivers/iommu/arm/arm-smmu/qcom_iommu.c | 2 +- drivers/iommu/fsl_pamu.c | 6 +++--- drivers/iommu/fsl_pamu_domain.c | 4 ++-- drivers/iommu/intel/pasid.c | 2 +- drivers/iommu/ipmmu-vmsa.c | 2 +- drivers/iommu/mtk_iommu.c | 9 ++++++--- drivers/iommu/omap-iommu.c | 4 ++-- drivers/iommu/rockchip-iommu.c | 4 +++- drivers/iommu/tegra-smmu.c | 2 +- drivers/iommu/virtio-iommu.c | 2 +- 12 files changed, 24 insertions(+), 19 deletions(-)