From: FelixCui-oc <FelixCui-oc@zhaoxin.com>
To: Lu Baolu <baolu.lu@linux.intel.com>,
Joerg Roedel <joro@8bytes.org>,
"iommu@lists.linux-foundation.org"
<iommu@lists.linux-foundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"David Woodhouse" <dwmw2@infradead.org>
Cc: CobeChen-oc <CobeChen-oc@zhaoxin.com>
Subject: 答复: 答复: 答复: 答复: 答复: 答复: 答复: 答复: [PATCH] iommu/vt-d:Add support for ACPI device in RMRR
Date: Sat, 8 Aug 2020 07:14:52 +0000 [thread overview]
Message-ID: <7fa8e455a69e4928b0638e2ef1030e95@zhaoxin.com> (raw)
In-Reply-To: <f631a3b2-5bd4-f48a-5ec5-0fc6118e1c95@linux.intel.com>
[-- Attachment #1: Type: text/plain, Size: 5820 bytes --]
Hi baolu,
The attachment is the new patch.
If you have any questions, you can contact me at any time.
Thanks.
Best regards
Felix cui-oc
-----邮件原件-----
发件人: Lu Baolu <baolu.lu@linux.intel.com>
发送时间: 2020年8月7日 16:08
收件人: FelixCui-oc <FelixCui-oc@zhaoxin.com>; Joerg Roedel <joro@8bytes.org>; iommu@lists.linux-foundation.org; linux-kernel@vger.kernel.org; David Woodhouse <dwmw2@infradead.org>
抄送: baolu.lu@linux.intel.com; RaymondPang-oc <RaymondPang-oc@zhaoxin.com>; CobeChen-oc <CobeChen-oc@zhaoxin.com>
主题: Re: 答复: 答复: 答复: 答复: 答复: 答复: 答复: [PATCH] iommu/vt-d:Add support for ACPI device in RMRR
Hi,
On 2020/8/7 11:29, FelixCui-oc wrote:
> Hi baolu,
> I understand what you mean is that you want to put the following processing code in the acpi_device_create_direct_mappings() into the probe_acpi_namespace_devices() ,right?
> If you mean it , I think it's OK.
Yes. If the acpi device has companion physical devices, then probe the companion devices; otherwise, probe the acpi device instead. Also, let's put detecting and probing acpi devices in different patches so that they could be easier for reviewing.
Best regards,
baolu
>
> if (pn_dev == NULL) {
> acpi_device->bus->iommu_ops = &intel_iommu_ops;
> ret = iommu_probe_device(acpi_device);
> if (ret) {
> pr_err("acpi_device probe fail! ret:%d\n", ret);
> return ret;
> }
> return 0;
> }
>
> Best regards
> Felix cui-oc
>
>
>
>
>
> -----邮件原件-----
> 发件人: Lu Baolu <baolu.lu@linux.intel.com>
> 发送时间: 2020年8月7日 9:08
> 收件人: FelixCui-oc <FelixCui-oc@zhaoxin.com>; Joerg Roedel
> <joro@8bytes.org>; iommu@lists.linux-foundation.org;
> linux-kernel@vger.kernel.org; David Woodhouse <dwmw2@infradead.org>
> 抄送: baolu.lu@linux.intel.com; RaymondPang-oc
> <RaymondPang-oc@zhaoxin.com>; CobeChen-oc <CobeChen-oc@zhaoxin.com>
> 主题: Re: 答复: 答复: 答复: 答复: 答复: 答复: [PATCH] iommu/vt-d:Add support for
> ACPI device in RMRR
>
> Hi Felix,
>
> On 2020/8/6 14:51, FelixCui-oc wrote:
>> Hi baolu,
>> >Sure. Before that, let me sync my understanding with you. You have an acpi namespace device in ANDD table, it also shows up in the device scope of a RMRR.
>> >Current code doesn't enumerate that device for the RMRR, hence iommu_create_device_direct_mappings() doesn't work for this device.
>>
>> >At the same time, probe_acpi_namespace_devices() doesn't work for this device, hence you want to add a home-made
>> >acpi_device_create_direct_mappings() helper.
>>
>> Your understanding is right.
>> But there is a problem that even if the namespace device in rmrr is enumerated in the code, probe_acpi_namespace_devices() also doesn't work for this device.
>> This is because the dev parameter of the iommu_create_device_direct_mappings() is not the namespace device in RMRR.
>> The actual parameter passed in is the namespace device's physical node device.
>> In iommu_create_device_direct_mappings(), the physical node device passed in cannot match the namespace device in rmrr->device[],right?
>> We need acpi_device_create_direct_mappings() helper ?
>>
>> In addition, adev->physical_node_list is related to the __HID of namespace device reported by the bios.
>> For example, if the __HID reported by the bios belongs to acpi_pnp_device_ids[], adev->physical_node_list has no devices.
>> So in acpi_device_create_direct_mappings(), I added the case that adev->physical_node_list is empty.
>
> Got you. Thanks!
>
> Have you ever tried to have probe_acpi_namespace_devices() handle the case of empty adev->physical_node_list at the same time?
>
> Best regards,
> baolu
>
>>
>>
>> Best regards
>> Felix cui
>>
>>
>>
>>
>> -----邮件原件-----
>> 发件人: Lu Baolu <baolu.lu@linux.intel.com>
>> 发送时间: 2020年8月6日 10:36
>> 收件人: FelixCui-oc <FelixCui-oc@zhaoxin.com>; Joerg Roedel
>> <joro@8bytes.org>; iommu@lists.linux-foundation.org;
>> linux-kernel@vger.kernel.org; David Woodhouse <dwmw2@infradead.org>
>> 抄送: baolu.lu@linux.intel.com; RaymondPang-oc
>> <RaymondPang-oc@zhaoxin.com>; CobeChen-oc <CobeChen-oc@zhaoxin.com>
>> 主题: Re: 答复: 答复: 答复: 答复: 答复: [PATCH] iommu/vt-d:Add support for ACPI
>> device in RMRR
>>
>> Hi Felix,
>>
>> On 8/5/20 3:37 PM, FelixCui-oc wrote:
>>> Hi baolu,
>>> Let me talk about why acpi_device_create_direct_mappings() is needed and please tell me if there is an error.
>>
>> Sure. Before that, let me sync my understanding with you. You have an acpi namespace device in ANDD table, it also shows up in the device scope of a RMRR. Current code doesn't enumerate that device for the RMRR, hence iommu_create_device_direct_mappings() doesn't work for this device.
>>
>> At the same time, probe_acpi_namespace_devices() doesn't work for
>> this device, hence you want to add a home-made
>> acpi_device_create_direct_mappings() helper.
>>
>> Did I get it right?
>>
>>> In the probe_acpi_namespace_devices() function, only the device in the addev->physical_node_list is probed,
>>> but we need to establish identity mapping for the namespace device in RMRR. These are two different devices.
>>
>> The namespace device has been probed and put in one drhd's device list.
>> Hence, it should be processed by probe_acpi_namespace_devices(). So the question is why there are no devices in addev->physical_node_list?
>>
>>> Therefore, the namespace device in RMRR is not mapped in probe_acpi_namespace_devices().
>>> acpi_device_create_direct_mappings() is to create direct mappings for namespace devices in RMRR.
>>
>> Best regards,
>> baolu
>>
[-- Attachment #2: 0001-iommu-vt-d-Add-support-for-detecting-ACPI-device-in-.patch --]
[-- Type: application/octet-stream, Size: 8336 bytes --]
From d5bb22f767f6336e1014ff6adb86c7654287b9b4 Mon Sep 17 00:00:00 2001
From: FelixCuioc <FelixCui-oc@zhaoxin.com>
Date: Sat, 8 Aug 2020 00:56:43 -0400
Subject: [PATCH] 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 <FelixCui-oc@zhaoxin.com>
---
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(&adev->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(&adev->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 = scope->bus;
- dmaru->devices[i].devfn = PCI_DEVFN(path->device,
- path->function);
- rcu_assign_pointer(dmaru->devices[i].dev,
- get_device(&adev->dev));
- return;
- }
- BUG_ON(i >= dmaru->devices_cnt);
- }
- }
- pr_warn("No IOMMU scope found for ANDD enumeration ID %d (%s)\n",
- device_number, dev_name(&adev->dev));
}
static int __init dmar_acpi_dev_scope_init(void)
@@ -766,7 +774,7 @@ static int __init dmar_acpi_dev_scope_init(void)
andd->device_name);
continue;
}
- dmar_acpi_insert_dev_scope(andd->device_number, adev);
+ dmar_acpi_bus_add_dev(andd->device_number, adev);
}
}
return 0;
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index ca557d351518..f774ef63d473 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4507,6 +4507,24 @@ int dmar_find_matched_atsr_unit(struct pci_dev *dev)
return ret;
}
+int dmar_rmrr_add_acpi_dev(u8 device_number, struct acpi_device *adev)
+{
+ int ret;
+ struct dmar_rmrr_unit *rmrru;
+ struct acpi_dmar_reserved_memory *rmrr;
+
+ list_for_each_entry(rmrru, &dmar_rmrr_units, list) {
+ rmrr = container_of(rmrru->hdr,
+ struct acpi_dmar_reserved_memory,
+ header);
+ ret = dmar_acpi_insert_dev_scope(device_number, adev, (void *)(rmrr + 1),
+ ((void *)rmrr) + rmrr->header.length,
+ rmrru->devices, rmrru->devices_cnt);
+ if (ret)
+ break;
+ }
+ return 0;
+}
int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
{
@@ -4523,7 +4541,7 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
rmrr = container_of(rmrru->hdr,
struct acpi_dmar_reserved_memory, header);
if (info->event == BUS_NOTIFY_ADD_DEVICE) {
- ret = dmar_insert_dev_scope(info, (void *)(rmrr + 1),
+ ret = dmar_pci_insert_dev_scope(info, (void *)(rmrr + 1),
((void *)rmrr) + rmrr->header.length,
rmrr->segment, rmrru->devices,
rmrru->devices_cnt);
@@ -4541,7 +4559,7 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
if (info->event == BUS_NOTIFY_ADD_DEVICE) {
- ret = dmar_insert_dev_scope(info, (void *)(atsr + 1),
+ ret = dmar_pci_insert_dev_scope(info, (void *)(atsr + 1),
(void *)atsr + atsr->header.length,
atsr->segment, atsru->devices,
atsru->devices_cnt);
diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index 65565820328a..881ac61a4336 100644
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -113,10 +113,14 @@ extern int dmar_parse_dev_scope(void *start, void *end, int *cnt,
struct dmar_dev_scope **devices, u16 segment);
extern void *dmar_alloc_dev_scope(void *start, void *end, int *cnt);
extern void dmar_free_dev_scope(struct dmar_dev_scope **devices, int *cnt);
-extern int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
+extern 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);
+extern 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);
+
extern int dmar_remove_dev_scope(struct dmar_pci_notify_info *info,
u16 segment, struct dmar_dev_scope *devices,
int count);
@@ -140,6 +144,7 @@ extern int dmar_parse_one_atsr(struct acpi_dmar_header *header, void *arg);
extern int dmar_check_one_atsr(struct acpi_dmar_header *hdr, void *arg);
extern int dmar_release_one_atsr(struct acpi_dmar_header *hdr, void *arg);
extern int dmar_iommu_hotplug(struct dmar_drhd_unit *dmaru, bool insert);
+extern int dmar_rmrr_add_acpi_dev(u8 device_number, struct acpi_device *adev);
extern int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info);
#else /* !CONFIG_INTEL_IOMMU: */
static inline int intel_iommu_init(void) { return -ENODEV; }
@@ -150,6 +155,11 @@ static inline void intel_iommu_shutdown(void) { }
#define dmar_check_one_atsr dmar_res_noop
#define dmar_release_one_atsr dmar_res_noop
+static inline int dmar_rmrr_add_acpi_dev(u8 device_number, struct acpi_device *adev)
+{
+ return 0;
+}
+
static inline int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
{
return 0;
--
2.17.1
[-- Attachment #3: 0001-iommu-vt-d-Add-support-for-probing-ACPI-device-in-RM.patch --]
[-- Type: application/octet-stream, Size: 3725 bytes --]
From a43a44fc775ec6fe6a7fe71b1fbe175b1e834e7c Mon Sep 17 00:00:00 2001
From: FelixCuioc <FelixCui-oc@zhaoxin.com>
Date: Sat, 8 Aug 2020 02:43:50 -0400
Subject: [PATCH] iommu/vt-d:Add support for probing ACPI device in RMRR
After acpi device in RMRR is detected,it is necessary
to establish a mapping for these devices.
In acpi_device_create_direct_mappings(),create a mapping
for the acpi device in RMRR.
Add a helper to achieve the acpi namespace device can
access the RMRR region.
Signed-off-by: FelixCuioc <FelixCui-oc@zhaoxin.com>
---
drivers/iommu/intel/iommu.c | 27 +++++++++++++++++++++++++++
drivers/iommu/iommu.c | 6 ++++++
include/linux/iommu.h | 3 +++
3 files changed, 36 insertions(+)
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index f774ef63d473..b31f02f41c96 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4797,6 +4797,20 @@ static int __init platform_optin_force_iommu(void)
return 1;
}
+static int acpi_device_create_direct_mappings(struct device *pn_dev, struct device *acpi_device)
+{
+ struct iommu_group *group;
+
+ acpi_device->bus->iommu_ops = &intel_iommu_ops;
+ group = iommu_group_get(pn_dev);
+ if (!group) {
+ pr_warn("ACPI name space devices create direct mappings wrong!\n");
+ return -1;
+ }
+ __acpi_device_create_direct_mappings(group, acpi_device);
+
+ return 0;
+}
static int __init probe_acpi_namespace_devices(void)
{
@@ -4812,6 +4826,7 @@ static int __init probe_acpi_namespace_devices(void)
struct acpi_device_physical_node *pn;
struct iommu_group *group;
struct acpi_device *adev;
+ struct device *pn_dev = NULL;
if (dev->bus != &acpi_bus_type)
continue;
@@ -4822,6 +4837,7 @@ static int __init probe_acpi_namespace_devices(void)
&adev->physical_node_list, node) {
group = iommu_group_get(pn->dev);
if (group) {
+ pn_dev = pn->dev;
iommu_group_put(group);
continue;
}
@@ -4830,7 +4846,18 @@ static int __init probe_acpi_namespace_devices(void)
ret = iommu_probe_device(pn->dev);
if (ret)
break;
+ pn_dev = pn->dev;
+ }
+ if (pn_dev == NULL) {
+ dev->bus->iommu_ops = &intel_iommu_ops;
+ ret = iommu_probe_device(dev);
+ if (ret) {
+ pr_err("acpi_device probe fail! ret:%d\n", ret);
+ return ret;
+ }
+ return 0;
}
+ ret = acpi_device_create_direct_mappings(pn_dev, dev);
mutex_unlock(&adev->physical_node_lock);
if (ret)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 609bd25bf154..4f714a2d5ef7 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -779,6 +779,12 @@ static bool iommu_is_attach_deferred(struct iommu_domain *domain,
return false;
}
+void __acpi_device_create_direct_mappings(struct iommu_group *group, struct device *acpi_device)
+{
+ iommu_create_device_direct_mappings(group, acpi_device);
+}
+EXPORT_SYMBOL_GPL(__acpi_device_create_direct_mappings);
+
/**
* iommu_group_add_device - add a device to an iommu group
* @group: the group into which to add the device (reference should be held)
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index fee209efb756..9be134775886 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -514,6 +514,9 @@ extern void iommu_domain_window_disable(struct iommu_domain *domain, u32 wnd_nr)
extern int report_iommu_fault(struct iommu_domain *domain, struct device *dev,
unsigned long iova, int flags);
+extern void __acpi_device_create_direct_mappings(struct iommu_group *group,
+ struct device *acpi_device);
+
static inline void iommu_flush_tlb_all(struct iommu_domain *domain)
{
if (domain->ops->flush_iotlb_all)
--
2.17.1
[-- Attachment #4: Type: text/plain, Size: 156 bytes --]
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prev parent reply other threads:[~2020-08-08 7:15 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-02 10:07 [PATCH] iommu/vt-d:Add support for ACPI device in RMRR FelixCuioc
2020-08-03 2:31 ` Lu Baolu
2020-08-03 4:40 ` 答复: " FelixCui-oc
2020-08-03 6:18 ` Lu Baolu
2020-08-03 6:52 ` 答复: " FelixCui-oc
2020-08-03 8:25 ` Lu Baolu
2020-08-03 9:01 ` 答复: " FelixCui-oc
2020-08-03 9:41 ` FelixCui-oc
2020-08-04 1:11 ` Lu Baolu
2020-08-04 3:11 ` 答复: " FelixCui-oc
2020-08-05 2:56 ` Lu Baolu
2020-08-05 7:37 ` 答复: " FelixCui-oc
2020-08-06 2:36 ` Lu Baolu
2020-08-06 6:51 ` 答复: " FelixCui-oc
2020-08-07 1:07 ` Lu Baolu
2020-08-07 3:29 ` 答复: " FelixCui-oc
2020-08-07 8:08 ` Lu Baolu
2020-08-08 7:14 ` FelixCui-oc [this message]
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