diff options
| -rw-r--r-- | arch/powerpc/include/asm/kvm_book3s_64.h | 58 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_hv.c | 8 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rm_mmu.c | 12 |
3 files changed, 44 insertions, 34 deletions
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h index 9c1ff330c805..a1ecb14e4442 100644 --- a/arch/powerpc/include/asm/kvm_book3s_64.h +++ b/arch/powerpc/include/asm/kvm_book3s_64.h @@ -159,36 +159,46 @@ static inline int hpte_cache_flags_ok(unsigned long ptel, unsigned long io_type) } /* - * Lock and read a linux PTE. If it's present and writable, atomically - * set dirty and referenced bits and return the PTE, otherwise return 0. + * If it's present and writable, atomically set dirty and referenced bits and + * return the PTE, otherwise return 0. If we find a transparent hugepage + * and if it is marked splitting we return 0; */ -static inline pte_t kvmppc_read_update_linux_pte(pte_t *p, int writing) +static inline pte_t kvmppc_read_update_linux_pte(pte_t *ptep, int writing, + unsigned int hugepage) { - pte_t pte, tmp; - - /* wait until _PAGE_BUSY is clear then set it atomically */ - __asm__ __volatile__ ( - "1: ldarx %0,0,%3\n" - " andi. %1,%0,%4\n" - " bne- 1b\n" - " ori %1,%0,%4\n" - " stdcx. %1,0,%3\n" - " bne- 1b" - : "=&r" (pte), "=&r" (tmp), "=m" (*p) - : "r" (p), "i" (_PAGE_BUSY) - : "cc"); - - if (pte_present(pte)) { - pte = pte_mkyoung(pte); - if (writing && pte_write(pte)) - pte = pte_mkdirty(pte); - } + pte_t old_pte, new_pte = __pte(0); + + while (1) { + old_pte = pte_val(*ptep); + /* + * wait until _PAGE_BUSY is clear then set it atomically + */ + if (unlikely(old_pte & _PAGE_BUSY)) { + cpu_relax(); + continue; + } +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + /* If hugepage and is trans splitting return None */ + if (unlikely(hugepage && + pmd_trans_splitting(pte_pmd(old_pte)))) + return __pte(0); +#endif + /* If pte is not present return None */ + if (unlikely(!(old_pte & _PAGE_PRESENT))) + return __pte(0); - *p = pte; /* clears _PAGE_BUSY */ + new_pte = pte_mkyoung(old_pte); + if (writing && pte_write(old_pte)) + new_pte = pte_mkdirty(new_pte); - return pte; + if (old_pte == __cmpxchg_u64((unsigned long *)ptep, old_pte, + new_pte)) + break; + } + return new_pte; } + /* Return HPTE cache control bits corresponding to Linux pte bits */ static inline unsigned long hpte_cache_bits(unsigned long pte_val) { diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 5880dfb31074..710d31317d81 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -675,6 +675,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, } /* if the guest wants write access, see if that is OK */ if (!writing && hpte_is_writable(r)) { + unsigned int hugepage_shift; pte_t *ptep, pte; /* @@ -683,9 +684,10 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, */ rcu_read_lock_sched(); ptep = find_linux_pte_or_hugepte(current->mm->pgd, - hva, NULL); - if (ptep && pte_present(*ptep)) { - pte = kvmppc_read_update_linux_pte(ptep, 1); + hva, &hugepage_shift); + if (ptep) { + pte = kvmppc_read_update_linux_pte(ptep, 1, + hugepage_shift); if (pte_write(pte)) write_ok = 1; } diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c index dcf892d25a56..fc25689a9f35 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c @@ -139,20 +139,18 @@ static pte_t lookup_linux_pte(pgd_t *pgdir, unsigned long hva, { pte_t *ptep; unsigned long ps = *pte_sizep; - unsigned int shift; + unsigned int hugepage_shift; - ptep = find_linux_pte_or_hugepte(pgdir, hva, &shift); + ptep = find_linux_pte_or_hugepte(pgdir, hva, &hugepage_shift); if (!ptep) return __pte(0); - if (shift) - *pte_sizep = 1ul << shift; + if (hugepage_shift) + *pte_sizep = 1ul << hugepage_shift; else *pte_sizep = PAGE_SIZE; if (ps > *pte_sizep) return __pte(0); - if (!pte_present(*ptep)) - return __pte(0); - return kvmppc_read_update_linux_pte(ptep, writing); + return kvmppc_read_update_linux_pte(ptep, writing, hugepage_shift); } static inline void unlock_hpte(unsigned long *hpte, unsigned long hpte_v) |