Re: [PATCH] KVM: MIPS: fix compilation

[Paolo Bonzini <pbonzini@redhat.com>]

On 31/03/20 18:07, Mike Rapoport wrote:
> On Tue, Mar 31, 2020 at 11:47:49AM -0400, Paolo Bonzini wrote:
>> Commit 31168f033e37 is correct that pud_index() & __pud_offset() are the same
>> when pud_index() is actually provided, however it does not take into account
>> the __PAGETABLE_PUD_FOLDED case.  Provide kvm_pud_index so that MIPS KVM
>> compiles.
>>
>> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
>> ---
>>  arch/mips/kvm/mmu.c | 18 ++++++++++++------
>>  1 file changed, 12 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
>> index 7dad7a293eae..ccf98c22fd2c 100644
>> --- a/arch/mips/kvm/mmu.c
>> +++ b/arch/mips/kvm/mmu.c
>> @@ -25,6 +25,12 @@
>>  #define KVM_MMU_CACHE_MIN_PAGES 2
>>  #endif
>>  
>> +#if defined(__PAGETABLE_PUD_FOLDED)
>> +#define kvm_pud_index(gva) 0
>> +#else
>> +#define kvm_pud_index(gva) pud_index(gva)
>> +#endif
>> +
> 
> I'd prefer simply making pud_index() always defined. When pud level is
> folded asm-generic/pgtable-nopud.h will define PTRS_PER_PUD to 1 and
> pud_index() will evaluate to 0 anyway.

I won't queue this patch for now, let's wait for the MIPS people to say
what they prefer.  Thanks!

Paolo

> diff --git a/arch/mips/include/asm/pgtable-64.h b/arch/mips/include/asm/pgtable-64.h
> index f92716cfa4f4..ee5dc0c145b9 100644
> --- a/arch/mips/include/asm/pgtable-64.h
> +++ b/arch/mips/include/asm/pgtable-64.h
> @@ -172,6 +172,8 @@
>  
>  extern pte_t invalid_pte_table[PTRS_PER_PTE];
>  
> +#define pud_index(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
> +
>  #ifndef __PAGETABLE_PUD_FOLDED
>  /*
>   * For 4-level pagetables we defines these ourselves, for 3-level the
> @@ -210,8 +212,6 @@ static inline void p4d_clear(p4d_t *p4dp)
>  	p4d_val(*p4dp) = (unsigned long)invalid_pud_table;
>  }
>  
> -#define pud_index(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
> -
>  static inline unsigned long p4d_page_vaddr(p4d_t p4d)
>  {
>  	return p4d_val(p4d);
> 
>>  static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
>>  				  int min, int max)
>>  {
>> @@ -234,8 +240,8 @@ static bool kvm_mips_flush_gpa_pud(pud_t *pud, unsigned long start_gpa,
>>  {
>>  	pmd_t *pmd;
>>  	unsigned long end = ~0ul;
>> -	int i_min = pud_index(start_gpa);
>> -	int i_max = pud_index(end_gpa);
>> +	int i_min = kvm_pud_index(start_gpa);
>> +	int i_max = kvm_pud_index(end_gpa);
>>  	bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PUD - 1);
>>  	int i;
>>  
>> @@ -361,8 +367,8 @@ static int kvm_mips_##name##_pud(pud_t *pud, unsigned long start,	\
>>  	int ret = 0;							\
>>  	pmd_t *pmd;							\
>>  	unsigned long cur_end = ~0ul;					\
>> -	int i_min = pud_index(start);				\
>> -	int i_max = pud_index(end);					\
>> +	int i_min = kvm_pud_index(start);				\
>> +	int i_max = kvm_pud_index(end);					\
>>  	int i;								\
>>  									\
>>  	for (i = i_min; i <= i_max; ++i, start = 0) {			\
>> @@ -896,8 +902,8 @@ static bool kvm_mips_flush_gva_pud(pud_t *pud, unsigned long start_gva,
>>  {
>>  	pmd_t *pmd;
>>  	unsigned long end = ~0ul;
>> -	int i_min = pud_index(start_gva);
>> -	int i_max = pud_index(end_gva);
>> +	int i_min = kvm_pud_index(start_gva);
>> +	int i_max = kvm_pud_index(end_gva);
>>  	bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PUD - 1);
>>  	int i;
>>  
>> -- 
>> 2.18.2
>>
>