Invariant system id registers are populated with host values
at initialization time using their .reset function cb.

These are currently called get_* which is usually used by
the functions implementing the .get_user callback.

Change their function names to reset_* to reflect what they
are used for.

Signed-off-by: Sebastian Ott <sebott@redhat.com>
---
 arch/arm64/kvm/sys_regs.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 1b6ab483e21e..bae72a4ce72b 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -3795,8 +3795,8 @@ id_to_sys_reg_desc(struct kvm_vcpu *vcpu, u64 id,
  */
 
 #define FUNCTION_INVARIANT(reg)						\
-	static u64 get_##reg(struct kvm_vcpu *v,			\
-			      const struct sys_reg_desc *r)		\
+	static u64 reset_##reg(struct kvm_vcpu *v,			\
+			       const struct sys_reg_desc *r)		\
 	{								\
 		((struct sys_reg_desc *)r)->val = read_sysreg(reg);	\
 		return ((struct sys_reg_desc *)r)->val;			\
@@ -3808,9 +3808,9 @@ FUNCTION_INVARIANT(aidr_el1)
 
 /* ->val is filled in by kvm_sys_reg_table_init() */
 static struct sys_reg_desc invariant_sys_regs[] __ro_after_init = {
-	{ SYS_DESC(SYS_MIDR_EL1), NULL, get_midr_el1 },
-	{ SYS_DESC(SYS_REVIDR_EL1), NULL, get_revidr_el1 },
-	{ SYS_DESC(SYS_AIDR_EL1), NULL, get_aidr_el1 },
+	{ SYS_DESC(SYS_MIDR_EL1), NULL, reset_midr_el1 },
+	{ SYS_DESC(SYS_REVIDR_EL1), NULL, reset_revidr_el1 },
+	{ SYS_DESC(SYS_AIDR_EL1), NULL, reset_aidr_el1 },
 };
 
 static int get_invariant_sys_reg(u64 id, u64 __user *uaddr)
-- 
2.42.0

Hi Sebastian,

On 5/14/24 09:22, Sebastian Ott wrote:
> Invariant system id registers are populated with host values
> at initialization time using their .reset function cb.
get_##reg call read_sysreg(). I don't really understand the above
sentence. Please could you elaborate?

Thanks

Eric
> 
> These are currently called get_* which is usually used by
> the functions implementing the .get_user callback.
> 
> Change their function names to reset_* to reflect what they
> are used for.
> 
> Signed-off-by: Sebastian Ott <sebott@redhat.com>
> ---
>  arch/arm64/kvm/sys_regs.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
> index 1b6ab483e21e..bae72a4ce72b 100644
> --- a/arch/arm64/kvm/sys_regs.c
> +++ b/arch/arm64/kvm/sys_regs.c
> @@ -3795,8 +3795,8 @@ id_to_sys_reg_desc(struct kvm_vcpu *vcpu, u64 id,
>   */
>  
>  #define FUNCTION_INVARIANT(reg)						\
> -	static u64 get_##reg(struct kvm_vcpu *v,			\
> -			      const struct sys_reg_desc *r)		\
> +	static u64 reset_##reg(struct kvm_vcpu *v,			\
> +			       const struct sys_reg_desc *r)		\
>  	{								\
>  		((struct sys_reg_desc *)r)->val = read_sysreg(reg);	\
>  		return ((struct sys_reg_desc *)r)->val;			\
> @@ -3808,9 +3808,9 @@ FUNCTION_INVARIANT(aidr_el1)
>  
>  /* ->val is filled in by kvm_sys_reg_table_init() */
>  static struct sys_reg_desc invariant_sys_regs[] __ro_after_init = {
> -	{ SYS_DESC(SYS_MIDR_EL1), NULL, get_midr_el1 },
> -	{ SYS_DESC(SYS_REVIDR_EL1), NULL, get_revidr_el1 },
> -	{ SYS_DESC(SYS_AIDR_EL1), NULL, get_aidr_el1 },
> +	{ SYS_DESC(SYS_MIDR_EL1), NULL, reset_midr_el1 },
> +	{ SYS_DESC(SYS_REVIDR_EL1), NULL, reset_revidr_el1 },
> +	{ SYS_DESC(SYS_AIDR_EL1), NULL, reset_aidr_el1 },
>  };
>  
>  static int get_invariant_sys_reg(u64 id, u64 __user *uaddr)

Hej Eric,

On Wed, 29 May 2024, Eric Auger wrote:
> On 5/14/24 09:22, Sebastian Ott wrote:
>> Invariant system id registers are populated with host values
>> at initialization time using their .reset function cb.
> get_##reg call read_sysreg(). I don't really understand the above
> sentence. Please could you elaborate?
>

struct sys_reg_desc has 2 function pointers (among others):
.reset and .get_user . The functions implementing these are
usually named accordingly. For invariant registers only
.reset is used but set to functions that are called get_*
(which is usually used to implement .get_user).

E.g.: invariant_sys_regs[0].reset == get_midr_el1

When trying to figure out this code I was confused by this, hence
this patch..

Sebastian

Hi Sebastian,

On 5/29/24 17:29, Sebastian Ott wrote:
> Hej Eric,
> 
> On Wed, 29 May 2024, Eric Auger wrote:
>> On 5/14/24 09:22, Sebastian Ott wrote:
>>> Invariant system id registers are populated with host values
>>> at initialization time using their .reset function cb.
>> get_##reg call read_sysreg(). I don't really understand the above
>> sentence. Please could you elaborate?
>>
> 
> struct sys_reg_desc has 2 function pointers (among others):
> .reset and .get_user . The functions implementing these are
> usually named accordingly. For invariant registers only
> .reset is used but set to functions that are called get_*
> (which is usually used to implement .get_user).
> 
> E.g.: invariant_sys_regs[0].reset == get_midr_el1
> 
> When trying to figure out this code I was confused by this, hence
> this patch..

Ah OK, since ".reset=" was not used in the initilization I missed that.

feel free to add my
Reviewed-by: Eric Auger <eric.auger@redhat.com>


Eric
> 
> Sebastian
>