RE: [PATCH v2 2/4] iommu/vt-d: Add a helper to get svm and sdev for pasid
> From: Lu Baolu
> Sent: Monday, July 6, 2020 8:26 AM
>
> There are several places in the code that need to get the pointers of
> svm and sdev according to a pasid and device. Add a helper to achieve
> this for code consolidation and readability.
>
> Signed-off-by: Lu Baolu
> ---
> drivers/iommu/intel/svm.c | 121 +-
> 1 file changed, 68 insertions(+), 53 deletions(-)
>
> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
> index 25dd74f27252..c23167877b2b 100644
> --- a/drivers/iommu/intel/svm.c
> +++ b/drivers/iommu/intel/svm.c
> @@ -228,6 +228,50 @@ static LIST_HEAD(global_svm_list);
> list_for_each_entry((sdev), &(svm)->devs, list) \
> if ((d) != (sdev)->dev) {} else
>
> +static int pasid_to_svm_sdev(struct device *dev, unsigned int pasid,
> + struct intel_svm **rsvm,
> + struct intel_svm_dev **rsdev)
> +{
> + struct intel_svm_dev *d, *sdev = NULL;
> + struct intel_svm *svm;
> +
> + /* The caller should hold the pasid_mutex lock */
> + if (WARN_ON(!mutex_is_locked(_mutex)))
> + return -EINVAL;
> +
> + if (pasid == INVALID_IOASID || pasid >= PASID_MAX)
> + return -EINVAL;
> +
> + svm = ioasid_find(NULL, pasid, NULL);
> + if (IS_ERR(svm))
> + return PTR_ERR(svm);
> +
> + if (!svm)
> + goto out;
> +
> + /*
> + * If we found svm for the PASID, there must be at least one device
> + * bond.
> + */
> + if (WARN_ON(list_empty(>devs)))
> + return -EINVAL;
> +
> + rcu_read_lock();
> + list_for_each_entry_rcu(d, >devs, list) {
> + if (d->dev == dev) {
> + sdev = d;
> + break;
> + }
> + }
> + rcu_read_unlock();
> +
> +out:
> + *rsvm = svm;
> + *rsdev = sdev;
> +
> + return 0;
> +}
> +
> int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device
> *dev,
> struct iommu_gpasid_bind_data *data)
> {
> @@ -261,39 +305,27 @@ int intel_svm_bind_gpasid(struct iommu_domain
> *domain, struct device *dev,
> dmar_domain = to_dmar_domain(domain);
>
> mutex_lock(_mutex);
> - svm = ioasid_find(NULL, data->hpasid, NULL);
> - if (IS_ERR(svm)) {
> - ret = PTR_ERR(svm);
> + ret = pasid_to_svm_sdev(dev, data->hpasid, , );
> + if (ret)
> goto out;
> - }
>
> - if (svm) {
> + if (sdev) {
> /*
> - * If we found svm for the PASID, there must be at
> - * least one device bond, otherwise svm should be freed.
> + * For devices with aux domains, we should allow
> + * multiple bind calls with the same PASID and pdev.
>*/
> - if (WARN_ON(list_empty(>devs))) {
> - ret = -EINVAL;
> - goto out;
> + if (iommu_dev_feature_enabled(dev,
> IOMMU_DEV_FEAT_AUX)) {
> + sdev->users++;
> + } else {
> + dev_warn_ratelimited(dev,
> + "Already bound with PASID %u\n",
> + svm->pasid);
> + ret = -EBUSY;
> }
> + goto out;
> + }
>
> - for_each_svm_dev(sdev, svm, dev) {
> - /*
> - * For devices with aux domains, we should allow
> - * multiple bind calls with the same PASID and pdev.
> - */
> - if (iommu_dev_feature_enabled(dev,
> - IOMMU_DEV_FEAT_AUX))
> {
> - sdev->users++;
> - } else {
> - dev_warn_ratelimited(dev,
> - "Already bound with
> PASID %u\n",
> - svm->pasid);
> - ret = -EBUSY;
> - }
> - goto out;
> - }
> - } else {
> + if (!svm) {
> /* We come here when PASID has never been bond to a
> device. */
> svm = kzalloc(sizeof(*svm), GFP_KERNEL);
> if (!svm) {
> @@ -376,25 +408,17 @@ int intel_svm_unbind_gpasid(struct device *dev,
> int pasid)
> struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL);
> struct intel_svm_dev *sdev;
> struct intel_svm *svm;
> - int ret = -EINVAL;
> + int ret;
>
> if (WARN_ON(!iommu))
> return -EINVAL;
>
> mutex_lock(_mutex);
> - svm = ioasid_find(NULL, pasid, NULL);
> - if (!svm) {
> - ret = -EINVAL;
> - goto out;
> - }
> -
> - if (IS_ERR(svm)) {
> - ret = PTR_ERR(svm);
> + ret =
[PATCH v2 2/4] iommu/vt-d: Add a helper to get svm and sdev for pasid
There are several places in the code that need to get the pointers of
svm and sdev according to a pasid and device. Add a helper to achieve
this for code consolidation and readability.
Signed-off-by: Lu Baolu
---
drivers/iommu/intel/svm.c | 121 +-
1 file changed, 68 insertions(+), 53 deletions(-)
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 25dd74f27252..c23167877b2b 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -228,6 +228,50 @@ static LIST_HEAD(global_svm_list);
list_for_each_entry((sdev), &(svm)->devs, list) \
if ((d) != (sdev)->dev) {} else
+static int pasid_to_svm_sdev(struct device *dev, unsigned int pasid,
+struct intel_svm **rsvm,
+struct intel_svm_dev **rsdev)
+{
+ struct intel_svm_dev *d, *sdev = NULL;
+ struct intel_svm *svm;
+
+ /* The caller should hold the pasid_mutex lock */
+ if (WARN_ON(!mutex_is_locked(_mutex)))
+ return -EINVAL;
+
+ if (pasid == INVALID_IOASID || pasid >= PASID_MAX)
+ return -EINVAL;
+
+ svm = ioasid_find(NULL, pasid, NULL);
+ if (IS_ERR(svm))
+ return PTR_ERR(svm);
+
+ if (!svm)
+ goto out;
+
+ /*
+* If we found svm for the PASID, there must be at least one device
+* bond.
+*/
+ if (WARN_ON(list_empty(>devs)))
+ return -EINVAL;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(d, >devs, list) {
+ if (d->dev == dev) {
+ sdev = d;
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+out:
+ *rsvm = svm;
+ *rsdev = sdev;
+
+ return 0;
+}
+
int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
struct iommu_gpasid_bind_data *data)
{
@@ -261,39 +305,27 @@ int intel_svm_bind_gpasid(struct iommu_domain *domain,
struct device *dev,
dmar_domain = to_dmar_domain(domain);
mutex_lock(_mutex);
- svm = ioasid_find(NULL, data->hpasid, NULL);
- if (IS_ERR(svm)) {
- ret = PTR_ERR(svm);
+ ret = pasid_to_svm_sdev(dev, data->hpasid, , );
+ if (ret)
goto out;
- }
- if (svm) {
+ if (sdev) {
/*
-* If we found svm for the PASID, there must be at
-* least one device bond, otherwise svm should be freed.
+* For devices with aux domains, we should allow
+* multiple bind calls with the same PASID and pdev.
*/
- if (WARN_ON(list_empty(>devs))) {
- ret = -EINVAL;
- goto out;
+ if (iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX)) {
+ sdev->users++;
+ } else {
+ dev_warn_ratelimited(dev,
+"Already bound with PASID %u\n",
+svm->pasid);
+ ret = -EBUSY;
}
+ goto out;
+ }
- for_each_svm_dev(sdev, svm, dev) {
- /*
-* For devices with aux domains, we should allow
-* multiple bind calls with the same PASID and pdev.
-*/
- if (iommu_dev_feature_enabled(dev,
- IOMMU_DEV_FEAT_AUX)) {
- sdev->users++;
- } else {
- dev_warn_ratelimited(dev,
-"Already bound with PASID
%u\n",
-svm->pasid);
- ret = -EBUSY;
- }
- goto out;
- }
- } else {
+ if (!svm) {
/* We come here when PASID has never been bond to a device. */
svm = kzalloc(sizeof(*svm), GFP_KERNEL);
if (!svm) {
@@ -376,25 +408,17 @@ int intel_svm_unbind_gpasid(struct device *dev, int pasid)
struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL);
struct intel_svm_dev *sdev;
struct intel_svm *svm;
- int ret = -EINVAL;
+ int ret;
if (WARN_ON(!iommu))
return -EINVAL;
mutex_lock(_mutex);
- svm = ioasid_find(NULL, pasid, NULL);
- if (!svm) {
- ret = -EINVAL;
- goto out;
- }
-
- if (IS_ERR(svm)) {
- ret = PTR_ERR(svm);
+ ret = pasid_to_svm_sdev(dev, pasid, , );
+ if (ret)
goto out;
- }
- for_each_svm_dev(sdev, svm, dev) {
- ret = 0;
+
