x86/APIC: Drop APIC_BASE and use fix_to_virt()

[PATCH] x86/APIC: Drop APIC_BASE and use fix_to_virt()

Posted by Andrew Cooper 3 months, 3 weeks ago

Right now the apic_mem_*() helpers only compile because sizeof(void *) ==
sizeof(long long).  Switch to using fix_to_virt() which is a void *type.

Also adjust the two places where the APIC/IO-APIC virtual address is rendered
in a printk().

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Roger Pau Monné <roger.pau@citrix.com>

Split out of %L patch.
---
 xen/arch/x86/apic.c                |  4 ++--
 xen/arch/x86/include/asm/apic.h    | 10 +++++++---
 xen/arch/x86/include/asm/apicdef.h |  2 --
 xen/arch/x86/io_apic.c             |  4 ++--
 4 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/xen/arch/x86/apic.c b/xen/arch/x86/apic.c
index 6567af685a1b..7869c30e83f6 100644
--- a/xen/arch/x86/apic.c
+++ b/xen/arch/x86/apic.c
@@ -938,8 +938,8 @@ void __init init_apic_mappings(void)
         apic_phys = mp_lapic_addr;
 
     set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
-    apic_printk(APIC_VERBOSE, "mapped APIC to %08Lx (%08lx)\n", APIC_BASE,
-                apic_phys);
+    apic_printk(APIC_VERBOSE, "mapped APIC to %p (%08lx)\n",
+                fix_to_virt(FIX_APIC_BASE), apic_phys);
 
 __next:
     /*
diff --git a/xen/arch/x86/include/asm/apic.h b/xen/arch/x86/include/asm/apic.h
index a7798de02993..25faa54d9d10 100644
--- a/xen/arch/x86/include/asm/apic.h
+++ b/xen/arch/x86/include/asm/apic.h
@@ -51,12 +51,16 @@ const struct genapic *apic_x2apic_probe(void);
 
 static inline void apic_mem_write(unsigned int reg, uint32_t v)
 {
-	*((volatile u32 *)(APIC_BASE+reg)) = v;
+    volatile uint32_t *addr = fix_to_virt(FIX_APIC_BASE) + reg;
+
+    *addr = v;
 }
 
-static inline u32 apic_mem_read(unsigned int reg)
+static inline uint32_t apic_mem_read(unsigned int reg)
 {
-	return *((volatile u32 *)(APIC_BASE+reg));
+    volatile uint32_t *addr = fix_to_virt(FIX_APIC_BASE) + reg;
+
+    return *addr;
 }
 
 /* NOTE: in x2APIC mode, we should use apic_icr_write()/apic_icr_read() to
diff --git a/xen/arch/x86/include/asm/apicdef.h b/xen/arch/x86/include/asm/apicdef.h
index b0790fad1cdb..49e29ec80156 100644
--- a/xen/arch/x86/include/asm/apicdef.h
+++ b/xen/arch/x86/include/asm/apicdef.h
@@ -117,8 +117,6 @@
 /* Applicable to vectors, TPR, and PPR. */
 #define		APIC_PRIO_CLASS(v)	((v) & 0xF0)
 
-#define APIC_BASE __fix_to_virt(FIX_APIC_BASE)
-
 #define MAX_IO_APICS 128
 
 extern bool x2apic_enabled;
diff --git a/xen/arch/x86/io_apic.c b/xen/arch/x86/io_apic.c
index 7744b43f2414..772700584639 100644
--- a/xen/arch/x86/io_apic.c
+++ b/xen/arch/x86/io_apic.c
@@ -2596,8 +2596,8 @@ static void __init ioapic_init_mappings(void)
         }
 
         set_fixmap_nocache(idx, ioapic_phys);
-        apic_printk(APIC_VERBOSE, "mapped IOAPIC to %08Lx (%08lx)\n",
-                    __fix_to_virt(idx), ioapic_phys);
+        apic_printk(APIC_VERBOSE, "mapped IOAPIC to %p (%08lx)\n",
+                    fix_to_virt(idx), ioapic_phys);
 
         if ( bad_ioapic_register(i) )
         {
-- 
2.39.2

Re: [PATCH] x86/APIC: Drop APIC_BASE and use fix_to_virt()

Posted by Jan Beulich 3 months, 3 weeks ago

On 30.07.2024 14:17, Andrew Cooper wrote:
> Right now the apic_mem_*() helpers only compile because sizeof(void *) ==
> sizeof(long long).  Switch to using fix_to_virt() which is a void *type.
> 
> Also adjust the two places where the APIC/IO-APIC virtual address is rendered
> in a printk().
> 
> No functional change.
> 
> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>

Reviewed-by: Jan Beulich <jbeulich@suse.com>
ideally ...

> --- a/xen/arch/x86/include/asm/apic.h
> +++ b/xen/arch/x86/include/asm/apic.h
> @@ -51,12 +51,16 @@ const struct genapic *apic_x2apic_probe(void);
>  
>  static inline void apic_mem_write(unsigned int reg, uint32_t v)
>  {
> -	*((volatile u32 *)(APIC_BASE+reg)) = v;
> +    volatile uint32_t *addr = fix_to_virt(FIX_APIC_BASE) + reg;
> +
> +    *addr = v;
>  }
>  
> -static inline u32 apic_mem_read(unsigned int reg)
> +static inline uint32_t apic_mem_read(unsigned int reg)
>  {
> -	return *((volatile u32 *)(APIC_BASE+reg));
> +    volatile uint32_t *addr = fix_to_virt(FIX_APIC_BASE) + reg;

... with const added here.

Jan

Re: [PATCH] x86/APIC: Drop APIC_BASE and use fix_to_virt()

Posted by Andrew Cooper 3 months, 3 weeks ago

On 30/07/2024 1:20 pm, Jan Beulich wrote:
> On 30.07.2024 14:17, Andrew Cooper wrote:
>> Right now the apic_mem_*() helpers only compile because sizeof(void *) ==
>> sizeof(long long).  Switch to using fix_to_virt() which is a void *type.
>>
>> Also adjust the two places where the APIC/IO-APIC virtual address is rendered
>> in a printk().
>>
>> No functional change.
>>
>> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
> Reviewed-by: Jan Beulich <jbeulich@suse.com>
> ideally ...
>
>> --- a/xen/arch/x86/include/asm/apic.h
>> +++ b/xen/arch/x86/include/asm/apic.h
>> @@ -51,12 +51,16 @@ const struct genapic *apic_x2apic_probe(void);
>>  
>>  static inline void apic_mem_write(unsigned int reg, uint32_t v)
>>  {
>> -	*((volatile u32 *)(APIC_BASE+reg)) = v;
>> +    volatile uint32_t *addr = fix_to_virt(FIX_APIC_BASE) + reg;
>> +
>> +    *addr = v;
>>  }
>>  
>> -static inline u32 apic_mem_read(unsigned int reg)
>> +static inline uint32_t apic_mem_read(unsigned int reg)
>>  {
>> -	return *((volatile u32 *)(APIC_BASE+reg));
>> +    volatile uint32_t *addr = fix_to_virt(FIX_APIC_BASE) + reg;
> ... with const added here.

Oops yes.  Will fix.  Thanks.

~Andrew