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[PATCH v2 1/4] xen: arm: Add a new helper update_boot_mapping()

Ayan Kumar Halder posted 4 patches 3 months, 2 weeks ago
There is a newer version of this series
[PATCH v2 1/4] xen: arm: Add a new helper update_boot_mapping()
Posted by Ayan Kumar Halder 3 months, 2 weeks 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".

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.

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

diff --git a/xen/arch/arm/arm64/mmu/mm.c b/xen/arch/arm/arm64/mmu/mm.c
index 293acb67e0..72e089a339 100644
--- a/xen/arch/arm/arm64/mmu/mm.c
+++ b/xen/arch/arm/arm64/mmu/mm.c
@@ -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/mm.h b/xen/arch/arm/include/asm/mm.h
index f6ba611f01..e769d2d3b3 100644
--- a/xen/arch/arm/include/asm/mm.h
+++ b/xen/arch/arm/include/asm/mm.h
@@ -426,6 +426,8 @@ static inline void page_set_xenheap_gfn(struct page_info *p, gfn_t gfn)
     } while ( (y = cmpxchg(&p->u.inuse.type_info, x, nx)) != x );
 }
 
+void update_boot_mapping(bool enable);
+
 #endif /*  __ARCH_ARM_MM__ */
 /*
  * Local variables:
-- 
2.25.1
Re: [PATCH v2 1/4] xen: arm: Add a new helper update_boot_mapping()
Posted by Michal Orzel 3 months, 2 weeks ago 
Hi Ayan,

On 08/08/2024 14:09, 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".
> 
> 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.
> 
>  xen/arch/arm/arm64/mmu/mm.c   | 5 +++++
>  xen/arch/arm/arm64/smpboot.c  | 6 +++---
>  xen/arch/arm/include/asm/mm.h | 2 ++
>  3 files changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/xen/arch/arm/arm64/mmu/mm.c b/xen/arch/arm/arm64/mmu/mm.c
> index 293acb67e0..72e089a339 100644
> --- a/xen/arch/arm/arm64/mmu/mm.c
> +++ b/xen/arch/arm/arm64/mmu/mm.c
> @@ -125,6 +125,11 @@ void update_identity_mapping(bool enable)
>      BUG_ON(rc);
>  }
>  
> +void update_boot_mapping(bool enable)
> +{
> +    update_identity_mapping(enable);
With your approach, update_identity_mapping() would only be called from within this file,
therefore it should be marked as static and the prototype removed.

> +}
> +
>  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/mm.h b/xen/arch/arm/include/asm/mm.h
> index f6ba611f01..e769d2d3b3 100644
> --- a/xen/arch/arm/include/asm/mm.h
> +++ b/xen/arch/arm/include/asm/mm.h
> @@ -426,6 +426,8 @@ static inline void page_set_xenheap_gfn(struct page_info *p, gfn_t gfn)
>      } while ( (y = cmpxchg(&p->u.inuse.type_info, x, nx)) != x );
>  }
>  
> +void update_boot_mapping(bool enable);
The definition is only present for arm64. Shouldn't the prototype be moved to arm64 header?

~Michal
Re: [PATCH v2 1/4] xen: arm: Add a new helper update_boot_mapping()
Posted by Ayan Kumar Halder 3 months, 1 week ago 
On 09/08/2024 13:01, Michal Orzel wrote:
> Hi Ayan,
Hi Michal,
>
> On 08/08/2024 14:09, 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".
>>
>> 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.
>>
>>   xen/arch/arm/arm64/mmu/mm.c   | 5 +++++
>>   xen/arch/arm/arm64/smpboot.c  | 6 +++---
>>   xen/arch/arm/include/asm/mm.h | 2 ++
>>   3 files changed, 10 insertions(+), 3 deletions(-)
>>
>> diff --git a/xen/arch/arm/arm64/mmu/mm.c b/xen/arch/arm/arm64/mmu/mm.c
>> index 293acb67e0..72e089a339 100644
>> --- a/xen/arch/arm/arm64/mmu/mm.c
>> +++ b/xen/arch/arm/arm64/mmu/mm.c
>> @@ -125,6 +125,11 @@ void update_identity_mapping(bool enable)
>>       BUG_ON(rc);
>>   }
>>   
>> +void update_boot_mapping(bool enable)
>> +{
>> +    update_identity_mapping(enable);
> With your approach, update_identity_mapping() would only be called from within this file,
> therefore it should be marked as static and the prototype removed.
yes, agreed.
>
>> +}
>> +
>>   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/mm.h b/xen/arch/arm/include/asm/mm.h
>> index f6ba611f01..e769d2d3b3 100644
>> --- a/xen/arch/arm/include/asm/mm.h
>> +++ b/xen/arch/arm/include/asm/mm.h
>> @@ -426,6 +426,8 @@ static inline void page_set_xenheap_gfn(struct page_info *p, gfn_t gfn)
>>       } while ( (y = cmpxchg(&p->u.inuse.type_info, x, nx)) != x );
>>   }
>>   
>> +void update_boot_mapping(bool enable);
> The definition is only present for arm64. Shouldn't the prototype be moved to arm64 header?
Yes, I have replaced the prototype

update_identity_mapping() with update_boot_mapping() in xen/arch/arm/include/asm/arm64/mm.h

- Ayan

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