RE: [PATCH v2 1/4] iommu/vt-d: Refactor device_to_iommu() helper
> From: Lu Baolu
> Sent: Monday, July 6, 2020 8:26 AM
>
> It is refactored in two ways:
>
> - Make it global so that it could be used in other files.
>
> - Make bus/devfn optional so that callers could ignore these two returned
> values when they only want to get the coresponding iommu pointer.
>
> Signed-off-by: Lu Baolu
> ---
> drivers/iommu/intel/iommu.c | 55 +++--
> drivers/iommu/intel/svm.c | 8 +++---
> include/linux/intel-iommu.h | 3 +-
> 3 files changed, 21 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index d759e7234e98..de17952ed133 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -778,16 +778,16 @@ is_downstream_to_pci_bridge(struct device *dev,
> struct device *bridge)
> return false;
> }
>
> -static struct intel_iommu *device_to_iommu(struct device *dev, u8 *bus, u8
> *devfn)
> +struct intel_iommu *device_to_iommu(struct device *dev, u8 *bus, u8
> *devfn)
> {
> struct dmar_drhd_unit *drhd = NULL;
> + struct pci_dev *pdev = NULL;
> struct intel_iommu *iommu;
> struct device *tmp;
> - struct pci_dev *pdev = NULL;
> u16 segment = 0;
> int i;
>
> - if (iommu_dummy(dev))
> + if (!dev || iommu_dummy(dev))
> return NULL;
>
> if (dev_is_pci(dev)) {
> @@ -818,8 +818,10 @@ static struct intel_iommu *device_to_iommu(struct
> device *dev, u8 *bus, u8 *devf
> if (pdev && pdev->is_virtfn)
> goto got_pdev;
>
> - *bus = drhd->devices[i].bus;
> - *devfn = drhd->devices[i].devfn;
> + if (bus && devfn) {
> + *bus = drhd->devices[i].bus;
> + *devfn = drhd->devices[i].devfn;
> + }
> goto out;
> }
>
> @@ -829,8 +831,10 @@ static struct intel_iommu *device_to_iommu(struct
> device *dev, u8 *bus, u8 *devf
>
> if (pdev && drhd->include_all) {
> got_pdev:
> - *bus = pdev->bus->number;
> - *devfn = pdev->devfn;
> + if (bus && devfn) {
> + *bus = pdev->bus->number;
> + *devfn = pdev->devfn;
> + }
> goto out;
> }
> }
> @@ -5146,11 +5150,10 @@ static int aux_domain_add_dev(struct
> dmar_domain *domain,
> struct device *dev)
> {
> int ret;
> - u8 bus, devfn;
> unsigned long flags;
> struct intel_iommu *iommu;
>
> - iommu = device_to_iommu(dev, , );
> + iommu = device_to_iommu(dev, NULL, NULL);
> if (!iommu)
> return -ENODEV;
>
> @@ -5236,9 +5239,8 @@ static int prepare_domain_attach_device(struct
> iommu_domain *domain,
> struct dmar_domain *dmar_domain = to_dmar_domain(domain);
> struct intel_iommu *iommu;
> int addr_width;
> - u8 bus, devfn;
>
> - iommu = device_to_iommu(dev, , );
> + iommu = device_to_iommu(dev, NULL, NULL);
> if (!iommu)
> return -ENODEV;
>
> @@ -5658,9 +5660,8 @@ static bool intel_iommu_capable(enum
> iommu_cap cap)
> static struct iommu_device *intel_iommu_probe_device(struct device *dev)
> {
> struct intel_iommu *iommu;
> - u8 bus, devfn;
>
> - iommu = device_to_iommu(dev, , );
> + iommu = device_to_iommu(dev, NULL, NULL);
> if (!iommu)
> return ERR_PTR(-ENODEV);
>
> @@ -5673,9 +5674,8 @@ static struct iommu_device
> *intel_iommu_probe_device(struct device *dev)
> static void intel_iommu_release_device(struct device *dev)
> {
> struct intel_iommu *iommu;
> - u8 bus, devfn;
>
> - iommu = device_to_iommu(dev, , );
> + iommu = device_to_iommu(dev, NULL, NULL);
> if (!iommu)
> return;
>
> @@ -5825,37 +5825,14 @@ static struct iommu_group
> *intel_iommu_device_group(struct device *dev)
> return generic_device_group(dev);
> }
>
> -#ifdef CONFIG_INTEL_IOMMU_SVM
> -struct intel_iommu *intel_svm_device_to_iommu(struct device *dev)
> -{
> - struct intel_iommu *iommu;
> - u8 bus, devfn;
> -
> - if (iommu_dummy(dev)) {
> - dev_warn(dev,
> - "No IOMMU translation for device; cannot enable
> SVM\n");
> - return NULL;
> - }
> -
> - iommu = device_to_iommu(dev, , );
> - if ((!iommu)) {
> - dev_err(dev, "No IOMMU for device; cannot enable SVM\n");
> - return NULL;
> - }
> -
> - return iommu;
> -}
> -#endif /* CONFIG_INTEL_IOMMU_SVM */
> -
> static int intel_iommu_enable_auxd(struct device *dev)
> {
> struct device_domain_info *info;
> struct intel_iommu *iommu;
>
[PATCH v2 1/4] iommu/vt-d: Refactor device_to_iommu() helper
It is refactored in two ways:
- Make it global so that it could be used in other files.
- Make bus/devfn optional so that callers could ignore these two returned
values when they only want to get the coresponding iommu pointer.
Signed-off-by: Lu Baolu
---
drivers/iommu/intel/iommu.c | 55 +++--
drivers/iommu/intel/svm.c | 8 +++---
include/linux/intel-iommu.h | 3 +-
3 files changed, 21 insertions(+), 45 deletions(-)
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index d759e7234e98..de17952ed133 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -778,16 +778,16 @@ is_downstream_to_pci_bridge(struct device *dev, struct
device *bridge)
return false;
}
-static struct intel_iommu *device_to_iommu(struct device *dev, u8 *bus, u8
*devfn)
+struct intel_iommu *device_to_iommu(struct device *dev, u8 *bus, u8 *devfn)
{
struct dmar_drhd_unit *drhd = NULL;
+ struct pci_dev *pdev = NULL;
struct intel_iommu *iommu;
struct device *tmp;
- struct pci_dev *pdev = NULL;
u16 segment = 0;
int i;
- if (iommu_dummy(dev))
+ if (!dev || iommu_dummy(dev))
return NULL;
if (dev_is_pci(dev)) {
@@ -818,8 +818,10 @@ static struct intel_iommu *device_to_iommu(struct device
*dev, u8 *bus, u8 *devf
if (pdev && pdev->is_virtfn)
goto got_pdev;
- *bus = drhd->devices[i].bus;
- *devfn = drhd->devices[i].devfn;
+ if (bus && devfn) {
+ *bus = drhd->devices[i].bus;
+ *devfn = drhd->devices[i].devfn;
+ }
goto out;
}
@@ -829,8 +831,10 @@ static struct intel_iommu *device_to_iommu(struct device
*dev, u8 *bus, u8 *devf
if (pdev && drhd->include_all) {
got_pdev:
- *bus = pdev->bus->number;
- *devfn = pdev->devfn;
+ if (bus && devfn) {
+ *bus = pdev->bus->number;
+ *devfn = pdev->devfn;
+ }
goto out;
}
}
@@ -5146,11 +5150,10 @@ static int aux_domain_add_dev(struct dmar_domain
*domain,
struct device *dev)
{
int ret;
- u8 bus, devfn;
unsigned long flags;
struct intel_iommu *iommu;
- iommu = device_to_iommu(dev, , );
+ iommu = device_to_iommu(dev, NULL, NULL);
if (!iommu)
return -ENODEV;
@@ -5236,9 +5239,8 @@ static int prepare_domain_attach_device(struct
iommu_domain *domain,
struct dmar_domain *dmar_domain = to_dmar_domain(domain);
struct intel_iommu *iommu;
int addr_width;
- u8 bus, devfn;
- iommu = device_to_iommu(dev, , );
+ iommu = device_to_iommu(dev, NULL, NULL);
if (!iommu)
return -ENODEV;
@@ -5658,9 +5660,8 @@ static bool intel_iommu_capable(enum iommu_cap cap)
static struct iommu_device *intel_iommu_probe_device(struct device *dev)
{
struct intel_iommu *iommu;
- u8 bus, devfn;
- iommu = device_to_iommu(dev, , );
+ iommu = device_to_iommu(dev, NULL, NULL);
if (!iommu)
return ERR_PTR(-ENODEV);
@@ -5673,9 +5674,8 @@ static struct iommu_device
*intel_iommu_probe_device(struct device *dev)
static void intel_iommu_release_device(struct device *dev)
{
struct intel_iommu *iommu;
- u8 bus, devfn;
- iommu = device_to_iommu(dev, , );
+ iommu = device_to_iommu(dev, NULL, NULL);
if (!iommu)
return;
@@ -5825,37 +5825,14 @@ static struct iommu_group
*intel_iommu_device_group(struct device *dev)
return generic_device_group(dev);
}
-#ifdef CONFIG_INTEL_IOMMU_SVM
-struct intel_iommu *intel_svm_device_to_iommu(struct device *dev)
-{
- struct intel_iommu *iommu;
- u8 bus, devfn;
-
- if (iommu_dummy(dev)) {
- dev_warn(dev,
-"No IOMMU translation for device; cannot enable
SVM\n");
- return NULL;
- }
-
- iommu = device_to_iommu(dev, , );
- if ((!iommu)) {
- dev_err(dev, "No IOMMU for device; cannot enable SVM\n");
- return NULL;
- }
-
- return iommu;
-}
-#endif /* CONFIG_INTEL_IOMMU_SVM */
-
static int intel_iommu_enable_auxd(struct device *dev)
{
struct device_domain_info *info;
struct intel_iommu *iommu;
unsigned long flags;
- u8 bus, devfn;
int ret;
- iommu = device_to_iommu(dev, , );
+ iommu = device_to_iommu(dev, NULL, NULL);
if (!iommu
