Re: [PATCH 1/3] iommu/vt-d:Add support for detecting ACPI device in RMRR
On Wed, Aug 26, 2020 at 06:27:50AM -0400, FelixCuioc wrote:
> Some ACPI devices need to issue dma requests to access
> the reserved memory area.BIOS uses the device scope type
> ACPI_NAMESPACE_DEVICE in RMRR to report these ACPI devices.
> This patch add support for detecting ACPI devices in RMRR.
>
> Signed-off-by: FelixCuioc
> ---
> drivers/iommu/intel/dmar.c | 74 -
> drivers/iommu/intel/iommu.c | 22 ++-
> include/linux/dmar.h| 12 +-
> 3 files changed, 72 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
> index 93e6345f3414..024ca38dba12 100644
> --- a/drivers/iommu/intel/dmar.c
> +++ b/drivers/iommu/intel/dmar.c
> @@ -215,7 +215,7 @@ static bool dmar_match_pci_path(struct
> dmar_pci_notify_info *info, int bus,
> }
>
> /* Return: > 0 if match found, 0 if no match found, < 0 if error happens */
> -int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
> +int dmar_pci_insert_dev_scope(struct dmar_pci_notify_info *info,
> void *start, void*end, u16 segment,
> struct dmar_dev_scope *devices,
> int devices_cnt)
> @@ -304,7 +304,7 @@ static int dmar_pci_bus_add_dev(struct
> dmar_pci_notify_info *info)
>
> drhd = container_of(dmaru->hdr,
> struct acpi_dmar_hardware_unit, header);
> - ret = dmar_insert_dev_scope(info, (void *)(drhd + 1),
> + ret = dmar_pci_insert_dev_scope(info, (void *)(drhd + 1),
> ((void *)drhd) + drhd->header.length,
> dmaru->segment,
> dmaru->devices, dmaru->devices_cnt);
> @@ -696,48 +696,56 @@ dmar_find_matched_drhd_unit(struct pci_dev *dev)
>
> return dmaru;
> }
> -
> -static void __init dmar_acpi_insert_dev_scope(u8 device_number,
> - struct acpi_device *adev)
> +int dmar_acpi_insert_dev_scope(u8 device_number,
The patch deleted the blank line between functions. Make this function
bool, change the 1/0 to true/false. Add a comment explaining what the
return values mean.
> + struct acpi_device *adev,
> + void *start, void *end,
> + struct dmar_dev_scope *devices,
> + int devices_cnt)
> {
> - struct dmar_drhd_unit *dmaru;
> - struct acpi_dmar_hardware_unit *drhd;
> struct acpi_dmar_device_scope *scope;
> struct device *tmp;
> int i;
> struct acpi_dmar_pci_path *path;
>
> + for (; start < end; start += scope->length) {
> + scope = start;
Are we sure that there is enough space for sizeof(*scope) in end - start?
(I don't know this code so maybe we are).
> + if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_NAMESPACE)
> + continue;
> + if (scope->enumeration_id != device_number)
> + continue;
> + path = (void *)(scope + 1);
> + for_each_dev_scope(devices, devices_cnt, i, tmp)
> + if (tmp == NULL) {
> + devices[i].bus = scope->bus;
> + devices[i].devfn = PCI_DEVFN(path->device,
> path->function);
> + rcu_assign_pointer(devices[i].dev,
> +get_device(>dev));
> + return 1;
> + }
> + WARN_ON(i >= devices_cnt);
> + }
> + return 0;
> +}
> +static int dmar_acpi_bus_add_dev(u8 device_number, struct acpi_device *adev)
> +{
> + struct dmar_drhd_unit *dmaru;
> + struct acpi_dmar_hardware_unit *drhd;
> + int ret = 0;
This initialization is never used.
> +
> for_each_drhd_unit(dmaru) {
> drhd = container_of(dmaru->hdr,
> struct acpi_dmar_hardware_unit,
> header);
> + ret = dmar_acpi_insert_dev_scope(device_number, adev, (void
> *)(drhd+1),
> + ((void
> *)drhd)+drhd->header.length,
> + dmaru->devices,
> dmaru->devices_cnt);
> + if (ret)
> + break;
> + }
> + ret = dmar_rmrr_add_acpi_dev(device_number, adev);
What about if dmar_acpi_insert_dev_scope() always returns zero, do we
still want to call dmar_rmrr_add_acpi_dev()?
>
> - for (scope = (void *)(drhd + 1);
> - (unsigned long)scope < ((unsigned long)drhd) +
> drhd->header.length;
> - scope = ((void *)scope) + scope->length) {
> - if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_NAMESPACE)
> - continue;
> - if
[PATCH 1/3] iommu/vt-d:Add support for detecting ACPI device in RMRR
Some ACPI devices need to issue dma requests to access
the reserved memory area.BIOS uses the device scope type
ACPI_NAMESPACE_DEVICE in RMRR to report these ACPI devices.
This patch add support for detecting ACPI devices in RMRR.
Signed-off-by: FelixCuioc
---
drivers/iommu/intel/dmar.c | 74 -
drivers/iommu/intel/iommu.c | 22 ++-
include/linux/dmar.h| 12 +-
3 files changed, 72 insertions(+), 36 deletions(-)
diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 93e6345f3414..024ca38dba12 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -215,7 +215,7 @@ static bool dmar_match_pci_path(struct dmar_pci_notify_info
*info, int bus,
}
/* Return: > 0 if match found, 0 if no match found, < 0 if error happens */
-int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
+int dmar_pci_insert_dev_scope(struct dmar_pci_notify_info *info,
void *start, void*end, u16 segment,
struct dmar_dev_scope *devices,
int devices_cnt)
@@ -304,7 +304,7 @@ static int dmar_pci_bus_add_dev(struct dmar_pci_notify_info
*info)
drhd = container_of(dmaru->hdr,
struct acpi_dmar_hardware_unit, header);
- ret = dmar_insert_dev_scope(info, (void *)(drhd + 1),
+ ret = dmar_pci_insert_dev_scope(info, (void *)(drhd + 1),
((void *)drhd) + drhd->header.length,
dmaru->segment,
dmaru->devices, dmaru->devices_cnt);
@@ -696,48 +696,56 @@ dmar_find_matched_drhd_unit(struct pci_dev *dev)
return dmaru;
}
-
-static void __init dmar_acpi_insert_dev_scope(u8 device_number,
- struct acpi_device *adev)
+int dmar_acpi_insert_dev_scope(u8 device_number,
+ struct acpi_device *adev,
+ void *start, void *end,
+ struct dmar_dev_scope *devices,
+ int devices_cnt)
{
- struct dmar_drhd_unit *dmaru;
- struct acpi_dmar_hardware_unit *drhd;
struct acpi_dmar_device_scope *scope;
struct device *tmp;
int i;
struct acpi_dmar_pci_path *path;
+ for (; start < end; start += scope->length) {
+ scope = start;
+ if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_NAMESPACE)
+ continue;
+ if (scope->enumeration_id != device_number)
+ continue;
+ path = (void *)(scope + 1);
+ for_each_dev_scope(devices, devices_cnt, i, tmp)
+ if (tmp == NULL) {
+ devices[i].bus = scope->bus;
+ devices[i].devfn = PCI_DEVFN(path->device,
path->function);
+ rcu_assign_pointer(devices[i].dev,
+ get_device(>dev));
+ return 1;
+ }
+ WARN_ON(i >= devices_cnt);
+ }
+ return 0;
+}
+static int dmar_acpi_bus_add_dev(u8 device_number, struct acpi_device *adev)
+{
+ struct dmar_drhd_unit *dmaru;
+ struct acpi_dmar_hardware_unit *drhd;
+ int ret = 0;
+
for_each_drhd_unit(dmaru) {
drhd = container_of(dmaru->hdr,
struct acpi_dmar_hardware_unit,
header);
+ ret = dmar_acpi_insert_dev_scope(device_number, adev, (void
*)(drhd+1),
+ ((void
*)drhd)+drhd->header.length,
+ dmaru->devices,
dmaru->devices_cnt);
+ if (ret)
+ break;
+ }
+ ret = dmar_rmrr_add_acpi_dev(device_number, adev);
- for (scope = (void *)(drhd + 1);
-(unsigned long)scope < ((unsigned long)drhd) +
drhd->header.length;
-scope = ((void *)scope) + scope->length) {
- if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_NAMESPACE)
- continue;
- if (scope->enumeration_id != device_number)
- continue;
+ return ret;
- path = (void *)(scope + 1);
- pr_info("ACPI device \"%s\" under DMAR at %llx as
%02x:%02x.%d\n",
- dev_name(>dev), dmaru->reg_base_addr,
- scope->bus, path->device, path->function);
- for_each_dev_scope(dmaru->devices, dmaru->devices_cnt,
i, tmp)
- if (tmp == NULL) {
- dmaru->devices[i].bus =
