From patchwork Mon Apr 7 08:26:59 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincent Donnefort X-Patchwork-Id: 14039997 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 27038C36010 for ; Mon, 7 Apr 2025 08:33:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:Cc:To:From: Subject:Message-ID:References:Mime-Version:In-Reply-To:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=FdIqQbEGrH6LJCk5IMP3fGkEsrPpiEvGrmtBvupTZLs=; b=m+aEjNBIWZvswAg51NV79Vc8pQ RXjEacLF9Bhml5KonOrvi3Hhb9naLDLsRjLKmfnFVrGoXx+lqL0usDv6LrsL8YWEdhFUk6eBX84wg 3HJGaeis5K7Ny9OFyL5pt1ShN2F7ws83PSDRdUb/9Snk31ko3JZQ4tsIYBJzywFQnpDvl+RoMD1E+ NQiqad9MRsa1wyounCU+3gdqx9K/zRPpEKFRKsH2RgUUKkRNlvv4HzDqPt18y2gSrI/yrPSPdVn2a 6RMWVtaxA+9YFtK0oIOYYuQbq7d3KNsDKlSuY0EP6tOAOOGKA8fW2eoUNEdqjH9pQZ8QZs5+/gvYk PGT0In6g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u1hur-0000000H0z2-0dZo; Mon, 07 Apr 2025 08:33:13 +0000 Received: from mail-wm1-x34a.google.com ([2a00:1450:4864:20::34a]) by bombadil.infradead.org with esmtps (Exim 4.98.1 #2 (Red Hat Linux)) id 1u1hpQ-0000000Gzwy-43Ya for linux-arm-kernel@lists.infradead.org; Mon, 07 Apr 2025 08:27:38 +0000 Received: by mail-wm1-x34a.google.com with SMTP id 5b1f17b1804b1-43cec217977so26174295e9.0 for ; Mon, 07 Apr 2025 01:27:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1744014454; x=1744619254; darn=lists.infradead.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=FdIqQbEGrH6LJCk5IMP3fGkEsrPpiEvGrmtBvupTZLs=; b=FMGqqzPpz0SPX0F1wukTZZGnF83uEni/HSWCyt1MbQ48+UvOA1swmCLtvdfJZ+o0Jf aC2kVQ8YLPoUX7vlFVMulhOaLVV01jPuCHiOFCICdeEpzZnxz4EA+JoBck3Do4NWjWer m7iuPfJ0x6u4QqyC2VrNHI6qU/1XfdymgRW63zuBBINa/zRvP/JNrBmXai4SVRRm6GEX nRT9sadD821QGmKCVt7I719HXmvqx8Q7oAi/ZMoEoMeoJoi2hBIdCFZdB4tiHe9faO7Q XOiFl0jxUQm/bbG33TAn0BwNjsCWZixc5Ewo8UiMcCVtQL/fdS4e+nDA0atHRtLijxSk C9Ww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1744014454; x=1744619254; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=FdIqQbEGrH6LJCk5IMP3fGkEsrPpiEvGrmtBvupTZLs=; b=O/wjQoZ4vARZK7ZjERvuc1IxAQgCGdHaTi9dVK2xpMIQ/gKKX08cstDXxcJhtu70xk tmKd4hzUFzYsmgGxAJQrTBq6jTSPBhWnlSRuYiIWxPkZv0Z4mzUC17FqY4GCp+iUW/Hn hhP2MugjkugjzW5uQ8SJHJClsMBRwN/b4i9ZKwC+zggr+h/CKacNIfy33pz2oo1SoldT +EO/42vr6wZUlgR9ELQK7iH4FV2XcipQWu9dI2jHMCZtbgmQBTdmdJAOC5Sg6Qwt1pg7 rtIjgtym4mmJj8Rr4ObTBWysZEZx5bJqi0lOwo3IOvdlBBY/YXgpM4xDzL3Z/r4vK+Y1 ATVw== X-Forwarded-Encrypted: i=1; AJvYcCV0zt/5/CyleZpqumoFqpOfQQ9Cty0FtovtNFiPSaYOLuEIpD1ktabqYnQQh8l+UBxJ0M1hanLIOYjmYSPTkNeK@lists.infradead.org X-Gm-Message-State: AOJu0YwPAwxIvcyRNaIwwfFEDuJ2DKpf2V9qqBm2M/SYCG1mnYgoIwhC 1KCeqawM8p3wGOmUNLiqx0bpFdfVyBpWaVlU89aMnb3JoE9nwXtuViUWDv5iXoKhfoP1vG5DU4G T2Obk9IuDoNzyXoneww== X-Google-Smtp-Source: AGHT+IHsGgikQanBubWw9n3TBOvtvQ0/2An9oSz0STzP+avD7elmsw808grIhtyKdtPWcqWYMd99e7w8hY/KmQYG X-Received: from wmcq3.prod.google.com ([2002:a05:600c:c103:b0:43d:41a2:b768]) (user=vdonnefort job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:1e23:b0:43d:8ea:8d80 with SMTP id 5b1f17b1804b1-43ecf81b197mr105228475e9.5.1744014454734; Mon, 07 Apr 2025 01:27:34 -0700 (PDT) Date: Mon, 7 Apr 2025 09:26:59 +0100 In-Reply-To: <20250407082706.1239603-1-vdonnefort@google.com> Mime-Version: 1.0 References: <20250407082706.1239603-1-vdonnefort@google.com> X-Mailer: git-send-email 2.49.0.504.g3bcea36a83-goog Message-ID: <20250407082706.1239603-3-vdonnefort@google.com> Subject: [PATCH v3 2/9] KVM: arm64: Add a range to __pkvm_host_share_guest() From: Vincent Donnefort To: maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org Cc: qperret@google.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, kernel-team@android.com, Vincent Donnefort X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250407_012737_018465_4481F00D X-CRM114-Status: GOOD ( 17.45 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org In preparation for supporting stage-2 huge mappings for np-guest. Add a nr_pages argument to the __pkvm_host_share_guest hypercall. This range supports only two values: 1 or PMD_SIZE / PAGE_SIZE (that is 512 on a 4K-pages system). Signed-off-by: Vincent Donnefort diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h index ea0a704da9b8..96f673f42e8e 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h +++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h @@ -39,7 +39,7 @@ int __pkvm_host_donate_hyp(u64 pfn, u64 nr_pages); int __pkvm_hyp_donate_host(u64 pfn, u64 nr_pages); int __pkvm_host_share_ffa(u64 pfn, u64 nr_pages); int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages); -int __pkvm_host_share_guest(u64 pfn, u64 gfn, struct pkvm_hyp_vcpu *vcpu, +int __pkvm_host_share_guest(u64 pfn, u64 gfn, u64 nr_pages, struct pkvm_hyp_vcpu *vcpu, enum kvm_pgtable_prot prot); int __pkvm_host_unshare_guest(u64 gfn, struct pkvm_hyp_vm *hyp_vm); int __pkvm_host_relax_perms_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu, enum kvm_pgtable_prot prot); diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c index 2c37680d954c..e71601746935 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -249,7 +249,8 @@ static void handle___pkvm_host_share_guest(struct kvm_cpu_context *host_ctxt) { DECLARE_REG(u64, pfn, host_ctxt, 1); DECLARE_REG(u64, gfn, host_ctxt, 2); - DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3); + DECLARE_REG(u64, nr_pages, host_ctxt, 3); + DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 4); struct pkvm_hyp_vcpu *hyp_vcpu; int ret = -EINVAL; @@ -264,7 +265,7 @@ static void handle___pkvm_host_share_guest(struct kvm_cpu_context *host_ctxt) if (ret) goto out; - ret = __pkvm_host_share_guest(pfn, gfn, hyp_vcpu, prot); + ret = __pkvm_host_share_guest(pfn, gfn, nr_pages, hyp_vcpu, prot); out: cpu_reg(host_ctxt, 1) = ret; } diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c index 6a90e7687f1f..48bc0370515f 100644 --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c @@ -60,6 +60,9 @@ static void hyp_unlock_component(void) hyp_spin_unlock(&pkvm_pgd_lock); } +#define for_each_hyp_page(start, size, page) \ + for (page = hyp_phys_to_page(start); page < hyp_phys_to_page((start) + (size)); page++) + static void *host_s2_zalloc_pages_exact(size_t size) { void *addr = hyp_alloc_pages(&host_s2_pool, get_order(size)); @@ -507,10 +510,10 @@ int host_stage2_idmap_locked(phys_addr_t addr, u64 size, static void __host_update_page_state(phys_addr_t addr, u64 size, enum pkvm_page_state state) { - phys_addr_t end = addr + size; + struct hyp_page *page; - for (; addr < end; addr += PAGE_SIZE) - hyp_phys_to_page(addr)->host_state = state; + for_each_hyp_page(addr, size, page) + page->host_state = state; } int host_stage2_set_owner_locked(phys_addr_t addr, u64 size, u8 owner_id) @@ -625,16 +628,16 @@ static int check_page_state_range(struct kvm_pgtable *pgt, u64 addr, u64 size, static int __host_check_page_state_range(u64 addr, u64 size, enum pkvm_page_state state) { - u64 end = addr + size; + struct hyp_page *page; int ret; - ret = check_range_allowed_memory(addr, end); + ret = check_range_allowed_memory(addr, addr + size); if (ret) return ret; hyp_assert_lock_held(&host_mmu.lock); - for (; addr < end; addr += PAGE_SIZE) { - if (hyp_phys_to_page(addr)->host_state != state) + for_each_hyp_page(addr, size, page) { + if (page->host_state != state) return -EPERM; } @@ -684,10 +687,9 @@ static enum pkvm_page_state guest_get_page_state(kvm_pte_t pte, u64 addr) return pkvm_getstate(kvm_pgtable_stage2_pte_prot(pte)); } -static int __guest_check_page_state_range(struct pkvm_hyp_vcpu *vcpu, u64 addr, +static int __guest_check_page_state_range(struct pkvm_hyp_vm *vm, u64 addr, u64 size, enum pkvm_page_state state) { - struct pkvm_hyp_vm *vm = pkvm_hyp_vcpu_to_hyp_vm(vcpu); struct check_walk_data d = { .desired = state, .get_page_state = guest_get_page_state, @@ -894,49 +896,81 @@ int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages) return ret; } -int __pkvm_host_share_guest(u64 pfn, u64 gfn, struct pkvm_hyp_vcpu *vcpu, +static int __guest_check_transition_size(u64 phys, u64 ipa, u64 nr_pages, u64 *size) +{ + if (nr_pages == 1) { + *size = PAGE_SIZE; + return 0; + } + + /* We solely support PMD_SIZE huge-pages */ + if (nr_pages != (1 << (PMD_SHIFT - PAGE_SHIFT))) + return -EINVAL; + + if (!IS_ALIGNED(phys | ipa, PMD_SIZE)) + return -EINVAL; + + *size = PMD_SIZE; + return 0; +} + +int __pkvm_host_share_guest(u64 pfn, u64 gfn, u64 nr_pages, struct pkvm_hyp_vcpu *vcpu, enum kvm_pgtable_prot prot) { struct pkvm_hyp_vm *vm = pkvm_hyp_vcpu_to_hyp_vm(vcpu); u64 phys = hyp_pfn_to_phys(pfn); u64 ipa = hyp_pfn_to_phys(gfn); struct hyp_page *page; + u64 size; int ret; if (prot & ~KVM_PGTABLE_PROT_RWX) return -EINVAL; - ret = check_range_allowed_memory(phys, phys + PAGE_SIZE); + ret = __guest_check_transition_size(phys, ipa, nr_pages, &size); + if (ret) + return ret; + + ret = check_range_allowed_memory(phys, phys + size); if (ret) return ret; host_lock_component(); guest_lock_component(vm); - ret = __guest_check_page_state_range(vcpu, ipa, PAGE_SIZE, PKVM_NOPAGE); + ret = __guest_check_page_state_range(vm, ipa, size, PKVM_NOPAGE); if (ret) goto unlock; - page = hyp_phys_to_page(phys); - switch (page->host_state) { - case PKVM_PAGE_OWNED: - WARN_ON(__host_set_page_state_range(phys, PAGE_SIZE, PKVM_PAGE_SHARED_OWNED)); - break; - case PKVM_PAGE_SHARED_OWNED: - if (page->host_share_guest_count) - break; - /* Only host to np-guest multi-sharing is tolerated */ - WARN_ON(1); - fallthrough; - default: - ret = -EPERM; - goto unlock; + for_each_hyp_page(phys, size, page) { + switch (page->host_state) { + case PKVM_PAGE_OWNED: + continue; + case PKVM_PAGE_SHARED_OWNED: + if (page->host_share_guest_count == U32_MAX) { + ret = -EBUSY; + goto unlock; + } + + /* Only host to np-guest multi-sharing is tolerated */ + if (page->host_share_guest_count) + continue; + + fallthrough; + default: + ret = -EPERM; + goto unlock; + } + } + + for_each_hyp_page(phys, size, page) { + page->host_state = PKVM_PAGE_SHARED_OWNED; + page->host_share_guest_count++; } - WARN_ON(kvm_pgtable_stage2_map(&vm->pgt, ipa, PAGE_SIZE, phys, + WARN_ON(kvm_pgtable_stage2_map(&vm->pgt, ipa, size, phys, pkvm_mkstate(prot, PKVM_PAGE_SHARED_BORROWED), &vcpu->vcpu.arch.pkvm_memcache, 0)); - page->host_share_guest_count++; unlock: guest_unlock_component(vm); diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c index 0f89157d31fd..cad25357858f 100644 --- a/arch/arm64/kvm/pkvm.c +++ b/arch/arm64/kvm/pkvm.c @@ -364,7 +364,7 @@ int pkvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size, return -EINVAL; lockdep_assert_held_write(&kvm->mmu_lock); - ret = kvm_call_hyp_nvhe(__pkvm_host_share_guest, pfn, gfn, prot); + ret = kvm_call_hyp_nvhe(__pkvm_host_share_guest, pfn, gfn, 1, prot); if (ret) { /* Is the gfn already mapped due to a racing vCPU? */ if (ret == -EPERM)