Re: [PATCH] KVM: MIPS: fix compilation

From: Mike Rapoport <rppt@linux.ibm.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	linux-mips@vger.kernel.org, peterx@redhat.com
Subject: Re: [PATCH] KVM: MIPS: fix compilation
Date: Tue, 31 Mar 2020 19:07:03 +0300	[thread overview]
Message-ID: <20200331160703.GF30942@linux.ibm.com> (raw)
In-Reply-To: <20200331154749.5457-1-pbonzini@redhat.com>

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.

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
> 

-- 
Sincerely yours,
Mike.

