diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index ccb0cfb258684..cf6c52ff8b877 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -281,23 +281,72 @@ static phys_addr_t kvm_kaddr_to_phys(void *kaddr) } } -static int pkvm_share_hyp(phys_addr_t start, phys_addr_t end) +struct hyp_shared_pfn { + u64 pfn; + int count; + struct rb_node node; +}; + +static DEFINE_MUTEX(hyp_shared_pfns_lock); +static struct rb_root hyp_shared_pfns = RB_ROOT; + +static struct hyp_shared_pfn *find_shared_pfn(u64 pfn, struct rb_node ***node, + struct rb_node **parent) { - phys_addr_t addr; - int ret; + struct hyp_shared_pfn *this; + + *node = &hyp_shared_pfns.rb_node; + *parent = NULL; + while (**node) { + this = container_of(**node, struct hyp_shared_pfn, node); + *parent = **node; + if (this->pfn < pfn) + *node = &((**node)->rb_left); + else if (this->pfn > pfn) + *node = &((**node)->rb_right); + else + return this; + } - for (addr = ALIGN_DOWN(start, PAGE_SIZE); addr < end; addr += PAGE_SIZE) { - ret = kvm_call_hyp_nvhe(__pkvm_host_share_hyp, - __phys_to_pfn(addr)); - if (ret) - return ret; + return NULL; +} + +static int share_pfn_hyp(u64 pfn) +{ + struct rb_node **node, *parent; + struct hyp_shared_pfn *this; + int ret = 0; + + mutex_lock(&hyp_shared_pfns_lock); + this = find_shared_pfn(pfn, &node, &parent); + if (this) { + this->count++; + goto unlock; } - return 0; + this = kzalloc(sizeof(*this), GFP_KERNEL); + if (!this) { + ret = -ENOMEM; + goto unlock; + } + + this->pfn = pfn; + this->count = 1; + rb_link_node(&this->node, parent, node); + rb_insert_color(&this->node, &hyp_shared_pfns); + ret = kvm_call_hyp_nvhe(__pkvm_host_share_hyp, pfn, 1); +unlock: + mutex_unlock(&hyp_shared_pfns_lock); + + return ret; } int kvm_share_hyp(void *from, void *to) { + phys_addr_t start, end, cur; + u64 pfn; + int ret; + if (is_kernel_in_hyp_mode()) return 0; @@ -312,7 +361,16 @@ int kvm_share_hyp(void *from, void *to) if (kvm_host_owns_hyp_mappings()) return create_hyp_mappings(from, to, PAGE_HYP); - return pkvm_share_hyp(__pa(from), __pa(to)); + start = ALIGN_DOWN(__pa(from), PAGE_SIZE); + end = PAGE_ALIGN(__pa(to)); + for (cur = start; cur < end; cur += PAGE_SIZE) { + pfn = __phys_to_pfn(cur); + ret = share_pfn_hyp(pfn); + if (ret) + return ret; + } + + return 0; } /**