Re: [PATCH 1/5] iommu/tegra-smmu: Fix domain_alloc
Thanks for the feedback, Robin, and, Dmitry.
I mostly agree with all your comments, pls see my responses inline.
I'll make these fixes in V2.
On 1/17/19 8:50 AM, Robin Murphy wrote:
> On 17/01/2019 15:13, Dmitry Osipenko wrote:
>> 16.01.2019 23:50, Navneet Kumar пишет:
>>> * Allocate dma iova cookie for a domain while adding dma iommu
>>> devices.
>>> * Perform a stricter check for domain type parameter.
>>>
>>
>> Commit message should tell what exactly is getting "fixed". Apparently
>> you're trying to support T132 ARM64 here.
I'll fix it.
>>
>>> Signed-off-by: Navneet Kumar
>>> ---
>>> drivers/iommu/tegra-smmu.c | 43
>>> +++
>>> 1 file changed, 27 insertions(+), 16 deletions(-)
>>>
>>> diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
>>> index 543f7c9..ee4d8a8 100644
>>> --- a/drivers/iommu/tegra-smmu.c
>>> +++ b/drivers/iommu/tegra-smmu.c
>>> @@ -16,6 +16,7 @@
>>> #include
>>> #include
>>> #include
>>> +#include
>>> #include
>>> #include
>>> @@ -271,8 +272,10 @@ static bool tegra_smmu_capable(enum iommu_cap cap)
>>> static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
>>> {
>>> struct tegra_smmu_as *as;
>>> + int ret;
>>> - if (type != IOMMU_DOMAIN_UNMANAGED)
>>> + if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA &&
>>> + type != IOMMU_DOMAIN_IDENTITY)
>>> return NULL;
>>
>> Should be better to write these lines like this for the sake of readability:
>>
>> if (type != IOMMU_DOMAIN_UNMANAGED &&
>> type != IOMMU_DOMAIN_DMA &&
>> type != IOMMU_DOMAIN_IDENTITY)
>> return NULL;
>
> Furthermore, AFAICS there's no special handling being added for identity
> domains - don't pretend to support them by giving back a regular translation
> domain, that's just misleading and broken.
Agreed.
>
>>
>>
>>> as = kzalloc(sizeof(*as), GFP_KERNEL);
>>> @@ -281,26 +284,22 @@ static struct iommu_domain
>>> *tegra_smmu_domain_alloc(unsigned type)
>>> as->attr = SMMU_PD_READABLE | SMMU_PD_WRITABLE | SMMU_PD_NONSECURE;
>>> + ret = (type == IOMMU_DOMAIN_DMA) ? iommu_get_dma_cookie(>domain)
>>> :
>>> + -ENODEV;
>>
>> This makes to fail allocation of domain that has type other than
>> IOMMU_DOMAIN_DMA.
>>
>> Should be:
>>
>> if (type == IOMMU_DOMAIN_DMA) {
>> err = iommu_get_dma_cookie(>domain);
>> if (err)
>> goto free_as;
>> }
>>
Agreed.
>>
>>> + if (ret)
>>> + goto free_as;
>>> +
>>> as->pd = alloc_page(GFP_KERNEL | __GFP_DMA | __GFP_ZERO);
>>> - if (!as->pd) {
>>> - kfree(as);
>>> - return NULL;
>>> - }
>>> + if (!as->pd)
>>> + goto put_dma_cookie;
>>> as->count = kcalloc(SMMU_NUM_PDE, sizeof(u32), GFP_KERNEL);
>>> - if (!as->count) {
>>> - __free_page(as->pd);
>>> - kfree(as);
>>> - return NULL;
>>> - }
>>> + if (!as->count)
>>> + goto free_pd_range;
>>> as->pts = kcalloc(SMMU_NUM_PDE, sizeof(*as->pts), GFP_KERNEL);
>>> - if (!as->pts) {
>>> - kfree(as->count);
>>> - __free_page(as->pd);
>>> - kfree(as);
>>> - return NULL;
>>> - }
>>> + if (!as->pts)
>>> + goto free_pts;
>>> /* setup aperture */
>>> as->domain.geometry.aperture_start = 0;
>>> @@ -308,6 +307,18 @@ static struct iommu_domain
>>> *tegra_smmu_domain_alloc(unsigned type)
>>> as->domain.geometry.force_aperture = true;
>>> return >domain;
>>> +
>>> +free_pts:
>>> + kfree(as->pts);
>>> +free_pd_range:
>>> + __free_page(as->pd);
>>> +put_dma_cookie:
>>> + if (type == IOMMU_DOMAIN_DMA)
>
> FWIW you don't strictly need that check - since domain->iova_cookie won't be
> set for other domain types anyway, iommu_put_dma_cookie() will simply ignore
> them.
>
I'll still keep that check and not rely solely on the put_dma_cookie API to
handle this case.
This will keep the code robust even if the put_dma_cookie API changes in future
(for whatever reason).
It also looks like the canonical usage in other drivers.
>>> + iommu_put_dma_cookie(>domain);
>>> +free_as:
>>> + kfree(as);
>>> +
>>> + return NULL;
>>> }
>>> static void tegra_smmu_domain_free(struct iommu_domain *domain)
>
> How about not leaking the cookie when you free a DMA ops domain?
>
Agreed.
> Robin.
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH 2/5] iommu/tegra-smmu: Use non-secure register for flushing
On 1/17/19 7:25 AM, Dmitry Osipenko wrote:
> 16.01.2019 23:50, Navneet Kumar пишет:
>> Use PTB_ASID instead of SMMU_CONFIG to flush smmu.
>> PTB_ASID can be accessed from non-secure mode, SMMU_CONFIG cannot be.
>> Using SMMU_CONFIG could pose a problem when kernel doesn't have secure
>> mode access enabled from boot.
>>
>> Signed-off-by: Navneet Kumar
>> ---
>> drivers/iommu/tegra-smmu.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
>> index ee4d8a8..fa175d9 100644
>> --- a/drivers/iommu/tegra-smmu.c
>> +++ b/drivers/iommu/tegra-smmu.c
>> @@ -235,7 +235,7 @@ static inline void smmu_flush_tlb_group(struct
>> tegra_smmu *smmu,
>>
>> static inline void smmu_flush(struct tegra_smmu *smmu)
>> {
>> -smmu_readl(smmu, SMMU_CONFIG);
>> +smmu_readl(smmu, SMMU_PTB_ASID);
>> }
>>
>> static int tegra_smmu_alloc_asid(struct tegra_smmu *smmu, unsigned int *idp)
>>
>
> Driver writes to SMMU_CONFIG during of the probing. Looks like it's better to
> drop this patch for now and make it part of a complete solution that will add
> proper support for a stricter insecure-mode platforms.
>
Thanks for the comment Dmitry. On secure platforms, writing to SMMU_CONFIG will
be a no-op and
will pose no harm. Having this patch is important because it fixes the flushing
behavior on
such platforms, which is critical.
I propose to keep this patch as is, however, i can add more explanation to the
commit message,
stating the case of probe and how it will not have any ill effects. Pls
ACK/NACK, and i shall post
a V2.
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
[PATCH 3/5] iommu/tegra-smmu: Fix client enablement order
Enable clients' translation only after setting up the swgroups.
Signed-off-by: Navneet Kumar
---
drivers/iommu/tegra-smmu.c | 23 ++-
1 file changed, 14 insertions(+), 9 deletions(-)
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index fa175d9..1a44cf6 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -353,6 +353,20 @@ static void tegra_smmu_enable(struct tegra_smmu *smmu,
unsigned int swgroup,
unsigned int i;
u32 value;
+ group = tegra_smmu_find_swgroup(smmu, swgroup);
+ if (group) {
+ value = smmu_readl(smmu, group->reg);
+ value &= ~SMMU_ASID_MASK;
+ value |= SMMU_ASID_VALUE(asid);
+ value |= SMMU_ASID_ENABLE;
+ smmu_writel(smmu, value, group->reg);
+ } else {
+ pr_warn("%s group from swgroup %u not found\n", __func__,
+ swgroup);
+ /* No point moving ahead if group was not found */
+ return;
+ }
+
for (i = 0; i < smmu->soc->num_clients; i++) {
const struct tegra_mc_client *client = >soc->clients[i];
@@ -363,15 +377,6 @@ static void tegra_smmu_enable(struct tegra_smmu *smmu,
unsigned int swgroup,
value |= BIT(client->smmu.bit);
smmu_writel(smmu, value, client->smmu.reg);
}
-
- group = tegra_smmu_find_swgroup(smmu, swgroup);
- if (group) {
- value = smmu_readl(smmu, group->reg);
- value &= ~SMMU_ASID_MASK;
- value |= SMMU_ASID_VALUE(asid);
- value |= SMMU_ASID_ENABLE;
- smmu_writel(smmu, value, group->reg);
- }
}
static void tegra_smmu_disable(struct tegra_smmu *smmu, unsigned int swgroup,
--
2.7.4
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
[PATCH 2/5] iommu/tegra-smmu: Use non-secure register for flushing
Use PTB_ASID instead of SMMU_CONFIG to flush smmu.
PTB_ASID can be accessed from non-secure mode, SMMU_CONFIG cannot be.
Using SMMU_CONFIG could pose a problem when kernel doesn't have secure
mode access enabled from boot.
Signed-off-by: Navneet Kumar
---
drivers/iommu/tegra-smmu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index ee4d8a8..fa175d9 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -235,7 +235,7 @@ static inline void smmu_flush_tlb_group(struct tegra_smmu
*smmu,
static inline void smmu_flush(struct tegra_smmu *smmu)
{
- smmu_readl(smmu, SMMU_CONFIG);
+ smmu_readl(smmu, SMMU_PTB_ASID);
}
static int tegra_smmu_alloc_asid(struct tegra_smmu *smmu, unsigned int *idp)
--
2.7.4
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
[PATCH 4/5] iommu/tegra-smmu: Add PCI support
Add support for PCI devices.
Signed-off-by: Navneet Kumar
---
drivers/iommu/tegra-smmu.c | 47 +-
1 file changed, 34 insertions(+), 13 deletions(-)
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 1a44cf6..4b43c63 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -17,6 +17,7 @@
#include
#include
#include
+#include
#include
#include
@@ -820,7 +821,8 @@ tegra_smmu_find_group(struct tegra_smmu *smmu, unsigned int
swgroup)
return NULL;
}
-static struct iommu_group *tegra_smmu_group_get(struct tegra_smmu *smmu,
+static struct iommu_group *tegra_smmu_group_get(struct device *dev,
+ struct tegra_smmu *smmu,
unsigned int swgroup)
{
const struct tegra_smmu_group_soc *soc;
@@ -847,7 +849,11 @@ static struct iommu_group *tegra_smmu_group_get(struct
tegra_smmu *smmu,
INIT_LIST_HEAD(>list);
group->soc = soc;
- group->group = iommu_group_alloc();
+ if (dev_is_pci(dev))
+ group->group = pci_device_group(dev);
+ else
+ group->group = generic_device_group(dev);
+
if (IS_ERR(group->group)) {
devm_kfree(smmu->dev, group);
mutex_unlock(>lock);
@@ -864,13 +870,8 @@ static struct iommu_group *tegra_smmu_device_group(struct
device *dev)
{
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
struct tegra_smmu *smmu = dev->archdata.iommu;
- struct iommu_group *group;
- group = tegra_smmu_group_get(smmu, fwspec->ids[0]);
- if (!group)
- group = generic_device_group(dev);
-
- return group;
+ return tegra_smmu_group_get(dev, smmu, fwspec->ids[0]);
}
static int tegra_smmu_of_xlate(struct device *dev,
@@ -989,6 +990,28 @@ static void tegra_smmu_debugfs_exit(struct tegra_smmu
*smmu)
debugfs_remove_recursive(smmu->debugfs);
}
+static int tegra_smmu_iommu_bus_init(struct tegra_smmu *smmu)
+{
+ int err;
+
+ err = bus_set_iommu(_bus_type, _smmu_ops);
+ if (err < 0) {
+ iommu_device_unregister(>iommu);
+ iommu_device_sysfs_remove(>iommu);
+ return err;
+ }
+
+#ifdef CONFIG_PCI
+ if (!iommu_present(_bus_type)) {
+ pci_request_acs();
+ err = bus_set_iommu(_bus_type, _smmu_ops);
+ if (err < 0)
+ return err;
+ }
+#endif
+ return 0;
+}
+
struct tegra_smmu *tegra_smmu_probe(struct device *dev,
const struct tegra_smmu_soc *soc,
struct tegra_mc *mc)
@@ -1072,12 +1095,10 @@ struct tegra_smmu *tegra_smmu_probe(struct device *dev,
return ERR_PTR(err);
}
- err = bus_set_iommu(_bus_type, _smmu_ops);
- if (err < 0) {
- iommu_device_unregister(>iommu);
- iommu_device_sysfs_remove(>iommu);
+ err = tegra_smmu_iommu_bus_init(smmu);
+ if (err)
return ERR_PTR(err);
- }
+ err = bus_set_iommu(_bus_type, _smmu_ops);
if (IS_ENABLED(CONFIG_DEBUG_FS))
tegra_smmu_debugfs_init(smmu);
--
2.7.4
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
[PATCH 1/5] iommu/tegra-smmu: Fix domain_alloc
* Allocate dma iova cookie for a domain while adding dma iommu
devices.
* Perform a stricter check for domain type parameter.
Signed-off-by: Navneet Kumar
---
drivers/iommu/tegra-smmu.c | 43 +++
1 file changed, 27 insertions(+), 16 deletions(-)
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 543f7c9..ee4d8a8 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -16,6 +16,7 @@
#include
#include
#include
+#include
#include
#include
@@ -271,8 +272,10 @@ static bool tegra_smmu_capable(enum iommu_cap cap)
static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
{
struct tegra_smmu_as *as;
+ int ret;
- if (type != IOMMU_DOMAIN_UNMANAGED)
+ if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA &&
+ type != IOMMU_DOMAIN_IDENTITY)
return NULL;
as = kzalloc(sizeof(*as), GFP_KERNEL);
@@ -281,26 +284,22 @@ static struct iommu_domain
*tegra_smmu_domain_alloc(unsigned type)
as->attr = SMMU_PD_READABLE | SMMU_PD_WRITABLE | SMMU_PD_NONSECURE;
+ ret = (type == IOMMU_DOMAIN_DMA) ? iommu_get_dma_cookie(>domain) :
+ -ENODEV;
+ if (ret)
+ goto free_as;
+
as->pd = alloc_page(GFP_KERNEL | __GFP_DMA | __GFP_ZERO);
- if (!as->pd) {
- kfree(as);
- return NULL;
- }
+ if (!as->pd)
+ goto put_dma_cookie;
as->count = kcalloc(SMMU_NUM_PDE, sizeof(u32), GFP_KERNEL);
- if (!as->count) {
- __free_page(as->pd);
- kfree(as);
- return NULL;
- }
+ if (!as->count)
+ goto free_pd_range;
as->pts = kcalloc(SMMU_NUM_PDE, sizeof(*as->pts), GFP_KERNEL);
- if (!as->pts) {
- kfree(as->count);
- __free_page(as->pd);
- kfree(as);
- return NULL;
- }
+ if (!as->pts)
+ goto free_pts;
/* setup aperture */
as->domain.geometry.aperture_start = 0;
@@ -308,6 +307,18 @@ static struct iommu_domain
*tegra_smmu_domain_alloc(unsigned type)
as->domain.geometry.force_aperture = true;
return >domain;
+
+free_pts:
+ kfree(as->pts);
+free_pd_range:
+ __free_page(as->pd);
+put_dma_cookie:
+ if (type == IOMMU_DOMAIN_DMA)
+ iommu_put_dma_cookie(>domain);
+free_as:
+ kfree(as);
+
+ return NULL;
}
static void tegra_smmu_domain_free(struct iommu_domain *domain)
--
2.7.4
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
