Re: [PATCH] KVM: MIPS: fix compilation

From: Paolo Bonzini
Date: Tue Mar 31 2020 - 12:34:03 EST


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@xxxxxxxxxx>
>> ---
>> 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
>>
>