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[PATCH v3 1/4] xen: arm: Add a new helper update_boot_mapping()

Ayan Kumar Halder posted 4 patches 3 months, 1 week ago
There is a newer version of this series
[PATCH v3 1/4] xen: arm: Add a new helper update_boot_mapping()
Posted by Ayan Kumar Halder 3 months, 1 week ago 
update_boot_mapping() invokes update_identity_mapping() for the MMU specific
code.
Later when the MPU code is added, update_boot_mapping() would invoke the
equivalent.

The common code now invokes update_boot_mapping() instead of
update_identity_mapping(). So, that there is clear abstraction between the
common and MMU/MPU specific logic.

This is in continuation to commit
f661a20aa880: "Extract MMU-specific MM code".

update_identity_mapping() is now marked as static as it is called within
xen/arch/arm/arm64/mmu/mm.c only. Also, updated the prototype to
update_boot_mapping() which is now invoked from other files.

Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
---
Changes from :-

v1 - 1. Introduced update_boot_mapping() which invokes
update_identity_mapping() in MMU specific code.

v2 - 1. Make update_identity_mapping() static and update the prototype.

 xen/arch/arm/arm64/mmu/mm.c         | 7 ++++++-
 xen/arch/arm/arm64/smpboot.c        | 6 +++---
 xen/arch/arm/include/asm/arm64/mm.h | 2 +-
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/xen/arch/arm/arm64/mmu/mm.c b/xen/arch/arm/arm64/mmu/mm.c
index 293acb67e0..1afbbeda5a 100644
--- a/xen/arch/arm/arm64/mmu/mm.c
+++ b/xen/arch/arm/arm64/mmu/mm.c
@@ -111,7 +111,7 @@ void __init arch_setup_page_tables(void)
     prepare_runtime_identity_mapping();
 }
 
-void update_identity_mapping(bool enable)
+static void update_identity_mapping(bool enable)
 {
     paddr_t id_addr = virt_to_maddr(_start);
     int rc;
@@ -125,6 +125,11 @@ void update_identity_mapping(bool enable)
     BUG_ON(rc);
 }
 
+void update_boot_mapping(bool enable)
+{
+    update_identity_mapping(enable);
+}
+
 extern void switch_ttbr_id(uint64_t ttbr);
 
 typedef void (switch_ttbr_fn)(uint64_t ttbr);
diff --git a/xen/arch/arm/arm64/smpboot.c b/xen/arch/arm/arm64/smpboot.c
index a225fae64d..789f352ab6 100644
--- a/xen/arch/arm/arm64/smpboot.c
+++ b/xen/arch/arm/arm64/smpboot.c
@@ -112,18 +112,18 @@ int arch_cpu_up(int cpu)
     if ( !smp_enable_ops[cpu].prepare_cpu )
         return -ENODEV;
 
-    update_identity_mapping(true);
+    update_boot_mapping(true);
 
     rc = smp_enable_ops[cpu].prepare_cpu(cpu);
     if ( rc )
-        update_identity_mapping(false);
+        update_boot_mapping(false);
 
     return rc;
 }
 
 void arch_cpu_up_finish(void)
 {
-    update_identity_mapping(false);
+    update_boot_mapping(false);
 }
 
 /*
diff --git a/xen/arch/arm/include/asm/arm64/mm.h b/xen/arch/arm/include/asm/arm64/mm.h
index e0bd23a6ed..ac8d1f5c78 100644
--- a/xen/arch/arm/include/asm/arm64/mm.h
+++ b/xen/arch/arm/include/asm/arm64/mm.h
@@ -21,7 +21,7 @@ void arch_setup_page_tables(void);
  * Note that nested call (e.g. enable=true, enable=true) is not
  * supported.
  */
-void update_identity_mapping(bool enable);
+void update_boot_mapping(bool enable);
 
 #endif /* __ARM_ARM64_MM_H__ */
 
-- 
2.25.1
Re: [PATCH v3 1/4] xen: arm: Add a new helper update_boot_mapping()
Posted by Michal Orzel 3 months, 1 week ago 
Hi Ayan,

On 13/08/2024 19:13, Ayan Kumar Halder wrote:
> update_boot_mapping() invokes update_identity_mapping() for the MMU specific
> code.
> Later when the MPU code is added, update_boot_mapping() would invoke the
> equivalent.
> 
> The common code now invokes update_boot_mapping() instead of
> update_identity_mapping(). So, that there is clear abstraction between the
> common and MMU/MPU specific logic.
> 
> This is in continuation to commit
> f661a20aa880: "Extract MMU-specific MM code".
> 
> update_identity_mapping() is now marked as static as it is called within
> xen/arch/arm/arm64/mmu/mm.c only. Also, updated the prototype to
> update_boot_mapping() which is now invoked from other files.
> 
> Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
> ---
> Changes from :-
> 
> v1 - 1. Introduced update_boot_mapping() which invokes
> update_identity_mapping() in MMU specific code.
> 
> v2 - 1. Make update_identity_mapping() static and update the prototype.
> 
>  xen/arch/arm/arm64/mmu/mm.c         | 7 ++++++-
>  xen/arch/arm/arm64/smpboot.c        | 6 +++---
>  xen/arch/arm/include/asm/arm64/mm.h | 2 +-
>  3 files changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/xen/arch/arm/arm64/mmu/mm.c b/xen/arch/arm/arm64/mmu/mm.c
> index 293acb67e0..1afbbeda5a 100644
> --- a/xen/arch/arm/arm64/mmu/mm.c
> +++ b/xen/arch/arm/arm64/mmu/mm.c
> @@ -111,7 +111,7 @@ void __init arch_setup_page_tables(void)
>      prepare_runtime_identity_mapping();
>  }
>  
> -void update_identity_mapping(bool enable)
> +static void update_identity_mapping(bool enable)
>  {
>      paddr_t id_addr = virt_to_maddr(_start);
>      int rc;
> @@ -125,6 +125,11 @@ void update_identity_mapping(bool enable)
>      BUG_ON(rc);
>  }
>  
> +void update_boot_mapping(bool enable)
> +{
> +    update_identity_mapping(enable);
> +}
> +
>  extern void switch_ttbr_id(uint64_t ttbr);
>  
>  typedef void (switch_ttbr_fn)(uint64_t ttbr);
> diff --git a/xen/arch/arm/arm64/smpboot.c b/xen/arch/arm/arm64/smpboot.c
> index a225fae64d..789f352ab6 100644
> --- a/xen/arch/arm/arm64/smpboot.c
> +++ b/xen/arch/arm/arm64/smpboot.c
> @@ -112,18 +112,18 @@ int arch_cpu_up(int cpu)
>      if ( !smp_enable_ops[cpu].prepare_cpu )
>          return -ENODEV;
>  
> -    update_identity_mapping(true);
> +    update_boot_mapping(true);
>  
>      rc = smp_enable_ops[cpu].prepare_cpu(cpu);
>      if ( rc )
> -        update_identity_mapping(false);
> +        update_boot_mapping(false);
>  
>      return rc;
>  }
>  
>  void arch_cpu_up_finish(void)
>  {
> -    update_identity_mapping(false);
> +    update_boot_mapping(false);
>  }
>  
>  /*
> diff --git a/xen/arch/arm/include/asm/arm64/mm.h b/xen/arch/arm/include/asm/arm64/mm.h
> index e0bd23a6ed..ac8d1f5c78 100644
> --- a/xen/arch/arm/include/asm/arm64/mm.h
> +++ b/xen/arch/arm/include/asm/arm64/mm.h
> @@ -21,7 +21,7 @@ void arch_setup_page_tables(void);
>   * Note that nested call (e.g. enable=true, enable=true) is not
>   * supported.
>   */
> -void update_identity_mapping(bool enable);
> +void update_boot_mapping(bool enable);
The whole point of adding a wrapper was to avoid ambiguity \wrt identity mapping and MPU.
You changed the name of a function but left the comment which is pretty MMU specific. I think
it should be moved to update_identity_mapping.

Apart from that:
Reviewed-by: Michal Orzel <michal.orzel@amd.com>

~Michal
Re: [PATCH v3 1/4] xen: arm: Add a new helper update_boot_mapping()
Posted by Ayan Kumar Halder 3 months ago 
On 14/08/2024 13:50, Michal Orzel wrote:
> Hi Ayan,
Hi Michal,
>
> On 13/08/2024 19:13, Ayan Kumar Halder wrote:
>> update_boot_mapping() invokes update_identity_mapping() for the MMU specific
>> code.
>> Later when the MPU code is added, update_boot_mapping() would invoke the
>> equivalent.
>>
>> The common code now invokes update_boot_mapping() instead of
>> update_identity_mapping(). So, that there is clear abstraction between the
>> common and MMU/MPU specific logic.
>>
>> This is in continuation to commit
>> f661a20aa880: "Extract MMU-specific MM code".
>>
>> update_identity_mapping() is now marked as static as it is called within
>> xen/arch/arm/arm64/mmu/mm.c only. Also, updated the prototype to
>> update_boot_mapping() which is now invoked from other files.
>>
>> Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
>> ---
>> Changes from :-
>>
>> v1 - 1. Introduced update_boot_mapping() which invokes
>> update_identity_mapping() in MMU specific code.
>>
>> v2 - 1. Make update_identity_mapping() static and update the prototype.
>>
>>   xen/arch/arm/arm64/mmu/mm.c         | 7 ++++++-
>>   xen/arch/arm/arm64/smpboot.c        | 6 +++---
>>   xen/arch/arm/include/asm/arm64/mm.h | 2 +-
>>   3 files changed, 10 insertions(+), 5 deletions(-)
>>
>> diff --git a/xen/arch/arm/arm64/mmu/mm.c b/xen/arch/arm/arm64/mmu/mm.c
>> index 293acb67e0..1afbbeda5a 100644
>> --- a/xen/arch/arm/arm64/mmu/mm.c
>> +++ b/xen/arch/arm/arm64/mmu/mm.c
>> @@ -111,7 +111,7 @@ void __init arch_setup_page_tables(void)
>>       prepare_runtime_identity_mapping();
>>   }
>>   
>> -void update_identity_mapping(bool enable)
>> +static void update_identity_mapping(bool enable)
>>   {
>>       paddr_t id_addr = virt_to_maddr(_start);
>>       int rc;
>> @@ -125,6 +125,11 @@ void update_identity_mapping(bool enable)
>>       BUG_ON(rc);
>>   }
>>   
>> +void update_boot_mapping(bool enable)
>> +{
>> +    update_identity_mapping(enable);
>> +}
>> +
>>   extern void switch_ttbr_id(uint64_t ttbr);
>>   
>>   typedef void (switch_ttbr_fn)(uint64_t ttbr);
>> diff --git a/xen/arch/arm/arm64/smpboot.c b/xen/arch/arm/arm64/smpboot.c
>> index a225fae64d..789f352ab6 100644
>> --- a/xen/arch/arm/arm64/smpboot.c
>> +++ b/xen/arch/arm/arm64/smpboot.c
>> @@ -112,18 +112,18 @@ int arch_cpu_up(int cpu)
>>       if ( !smp_enable_ops[cpu].prepare_cpu )
>>           return -ENODEV;
>>   
>> -    update_identity_mapping(true);
>> +    update_boot_mapping(true);
>>   
>>       rc = smp_enable_ops[cpu].prepare_cpu(cpu);
>>       if ( rc )
>> -        update_identity_mapping(false);
>> +        update_boot_mapping(false);
>>   
>>       return rc;
>>   }
>>   
>>   void arch_cpu_up_finish(void)
>>   {
>> -    update_identity_mapping(false);
>> +    update_boot_mapping(false);
>>   }
>>   
>>   /*
>> diff --git a/xen/arch/arm/include/asm/arm64/mm.h b/xen/arch/arm/include/asm/arm64/mm.h
>> index e0bd23a6ed..ac8d1f5c78 100644
>> --- a/xen/arch/arm/include/asm/arm64/mm.h
>> +++ b/xen/arch/arm/include/asm/arm64/mm.h
>> @@ -21,7 +21,7 @@ void arch_setup_page_tables(void);
>>    * Note that nested call (e.g. enable=true, enable=true) is not
>>    * supported.
>>    */
>> -void update_identity_mapping(bool enable);
>> +void update_boot_mapping(bool enable);
> The whole point of adding a wrapper was to avoid ambiguity \wrt identity mapping and MPU.
> You changed the name of a function but left the comment which is pretty MMU specific. I think
> it should be moved to update_identity_mapping.

Yes, you are correct. I will move the comment before

static void update_identity_mapping(bool enable)

{...}

>
> Apart from that:
> Reviewed-by: Michal Orzel <michal.orzel@amd.com>

I will keep your R-b

- Ayan

Patchew 2.1-devel-b67e4c2

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