From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 06134C433EF for ; Fri, 25 Feb 2022 03:40:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237063AbiBYDk7 (ORCPT ); Thu, 24 Feb 2022 22:40:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33598 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234681AbiBYDk5 (ORCPT ); Thu, 24 Feb 2022 22:40:57 -0500 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A1CEB2023BF for ; Thu, 24 Feb 2022 19:40:26 -0800 (PST) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-2d07ae1145aso19899687b3.4 for ; Thu, 24 Feb 2022 19:40:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:cc; bh=crLC6KNPSW6pjgkY7QG68MqSuOvzKzstw/mmXuRH0uQ=; b=eMACZV7Ulgx7cpO0c0twpxn/qhqjJw2zVig3i+P7saVXlXADzihFwDG1AYC5zvgZWn mNe85tgfJeyqyRM6l3SarGtFKFIpVugzsd/xhQdc0U0VCoHhDtKrXHdt2lKagz2QB4WK vNWuKwFAcN6rYAL39YUrOkSDOWwtP1m31bpK1hfR/FE2trbiIWOY1ehGd9eQUk4/jQRs NGJsqCj9Y6904z2Ztz5PWXVW5W7Xo+clWqBDdn6bW0HRlMK1SpSKCwgYloVC23KXYV7i OJOo4hUh7s0PhDrHE+xo4khiI09oZwLFYmNvgE0a5jdJkDWsC3zDE9JxGGuoOzxsilsR rJ5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:cc; bh=crLC6KNPSW6pjgkY7QG68MqSuOvzKzstw/mmXuRH0uQ=; b=skMB/++SBBCXrVvjOSekpnIv33222YAX08wVu0DLofiJilieBHpGGyEMGiguf8wUWA /BNcJmGrTOeMNbPuKk1Cf40hWm8ElQvadvIEHxm9QPR7BeMyAkE5RVH1EwJ3wCBQO7oB U0qEFl8SUWVFhvBiJLyPxQgDjItXACHwhtT0zck7+5h03wS/6ALaIi6vO+JybgoiRSbP XNZ2EZIMeY1dkO1OKqxXlY/x30LWwYZvOBdtLJ7OZpMnuaN167kY5D7WSXeV72+AGSRU zV7z9SMV6SnAbv3vyciqgfDt0aLJAipSurlRyBpDY4wBMon40W1RC5CKLDqfL9TYHzj7 Wwhw== X-Gm-Message-State: AOAM532gySaqNYfczCY2Pu6/I1qaUM0ed/VcsQTxYHUFW92KatMbN9sq hAvFK2xzPNxU6P0jWLBZOZuOvtT9nStk9iiCjA== X-Google-Smtp-Source: ABdhPJwOno2FbkMIPrVxa3r/Jv3jyWkFh+CTqMQaXEkKcA6CWeuJZGCXA3mA7lF2W+OMJmTOcLVCDYV3FJvU1Uwfjg== X-Received: from kaleshsingh.mtv.corp.google.com ([2620:15c:211:200:3a50:90b2:e6a2:9060]) (user=kaleshsingh job=sendgmr) by 2002:a5b:ed1:0:b0:624:4085:cd0c with SMTP id a17-20020a5b0ed1000000b006244085cd0cmr5397836ybs.574.1645760425872; Thu, 24 Feb 2022 19:40:25 -0800 (PST) Date: Thu, 24 Feb 2022 19:34:47 -0800 In-Reply-To: <20220225033548.1912117-1-kaleshsingh@google.com> Message-Id: <20220225033548.1912117-3-kaleshsingh@google.com> Mime-Version: 1.0 References: <20220225033548.1912117-1-kaleshsingh@google.com> X-Mailer: git-send-email 2.35.1.574.g5d30c73bfb-goog Subject: [PATCH v4 2/8] KVM: arm64: Introduce pkvm_alloc_private_va_range() From: Kalesh Singh Cc: will@kernel.org, maz@kernel.org, qperret@google.com, tabba@google.com, surenb@google.com, kernel-team@android.com, Kalesh Singh , James Morse , Alexandru Elisei , Suzuki K Poulose , Catalin Marinas , Mark Rutland , Mark Brown , Masami Hiramatsu , Peter Collingbourne , "Madhavan T. Venkataraman" , Andrew Scull , Paolo Bonzini , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org pkvm_hyp_alloc_private_va_range() can be used to reserve private VA ranges in the pKVM nVHE hypervisor (). Also update __pkvm_create_private_mapping() to allow specifying an alignment for the private VA mapping. These will be used to implement stack guard pages for pKVM nVHE hypervisor (in a subsequent patch in the series). Credits to Quentin Perret for the idea of moving private VA allocation out of __pkvm_create_private_mapping() Signed-off-by: Kalesh Singh --- Changes in v4: - Handle null ptr in pkvm_alloc_private_va_range() and replace IS_ERR_OR_NULL checks in callers with IS_ERR checks, per Fuad - Fix kernel-doc comments format, per Fuad - Format __pkvm_create_private_mapping() prototype args (< 80 col), per Fuad Changes in v3: - Handle null ptr in IS_ERR_OR_NULL checks, per Mark Changes in v2: - Allow specifying an alignment for the private VA allocations, per Marc arch/arm64/kvm/hyp/include/nvhe/mm.h | 3 +- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 5 ++- arch/arm64/kvm/hyp/nvhe/mm.c | 60 +++++++++++++++++----------- arch/arm64/kvm/mmu.c | 2 +- 4 files changed, 43 insertions(+), 27 deletions(-) diff --git a/arch/arm64/kvm/hyp/include/nvhe/mm.h b/arch/arm64/kvm/hyp/include/nvhe/mm.h index 2d08510c6cc1..76d6fcf1d4f4 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/mm.h +++ b/arch/arm64/kvm/hyp/include/nvhe/mm.h @@ -20,7 +20,8 @@ int pkvm_cpu_set_vector(enum arm64_hyp_spectre_vector slot); int pkvm_create_mappings(void *from, void *to, enum kvm_pgtable_prot prot); int pkvm_create_mappings_locked(void *from, void *to, enum kvm_pgtable_prot prot); unsigned long __pkvm_create_private_mapping(phys_addr_t phys, size_t size, - enum kvm_pgtable_prot prot); + size_t align, enum kvm_pgtable_prot prot); +unsigned long pkvm_alloc_private_va_range(size_t size, size_t align); static inline void hyp_vmemmap_range(phys_addr_t phys, unsigned long size, unsigned long *start, unsigned long *end) diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c index 5e2197db0d32..96b2312a0f1d 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -158,9 +158,10 @@ static void handle___pkvm_create_private_mapping(struct kvm_cpu_context *host_ct { DECLARE_REG(phys_addr_t, phys, host_ctxt, 1); DECLARE_REG(size_t, size, host_ctxt, 2); - DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3); + DECLARE_REG(size_t, align, host_ctxt, 3); + DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 4); - cpu_reg(host_ctxt, 1) = __pkvm_create_private_mapping(phys, size, prot); + cpu_reg(host_ctxt, 1) = __pkvm_create_private_mapping(phys, size, align, prot); } static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt) diff --git a/arch/arm64/kvm/hyp/nvhe/mm.c b/arch/arm64/kvm/hyp/nvhe/mm.c index 526a7d6fa86f..e6355180aa49 100644 --- a/arch/arm64/kvm/hyp/nvhe/mm.c +++ b/arch/arm64/kvm/hyp/nvhe/mm.c @@ -37,38 +37,53 @@ static int __pkvm_create_mappings(unsigned long start, unsigned long size, return err; } -unsigned long __pkvm_create_private_mapping(phys_addr_t phys, size_t size, - enum kvm_pgtable_prot prot) +/** + * pkvm_alloc_private_va_range - Allocates a private VA range. + * @size: The size of the VA range to reserve. + * @align: The required alignment for the allocation. + * + * The private VA range is allocated above __io_map_base. + */ +unsigned long pkvm_alloc_private_va_range(size_t size, size_t align) { - unsigned long addr; - int err; + unsigned long base, addr; hyp_spin_lock(&pkvm_pgd_lock); - size = PAGE_ALIGN(size + offset_in_page(phys)); - addr = __io_map_base; - __io_map_base += size; + addr = ALIGN(__io_map_base, align); + + /* The allocated size is always a multiple of PAGE_SIZE */ + base = addr + PAGE_ALIGN(size); /* Are we overflowing on the vmemmap ? */ - if (__io_map_base > __hyp_vmemmap) { - __io_map_base -= size; + if (!addr || base > __hyp_vmemmap) addr = (unsigned long)ERR_PTR(-ENOMEM); - goto out; - } - - err = kvm_pgtable_hyp_map(&pkvm_pgtable, addr, size, phys, prot); - if (err) { - addr = (unsigned long)ERR_PTR(err); - goto out; - } + else + __io_map_base = base; - addr = addr + offset_in_page(phys); -out: hyp_spin_unlock(&pkvm_pgd_lock); return addr; } +unsigned long __pkvm_create_private_mapping(phys_addr_t phys, size_t size, + size_t align, enum kvm_pgtable_prot prot) +{ + unsigned long addr; + int err; + + size += offset_in_page(phys); + addr = pkvm_alloc_private_va_range(size, align); + if (IS_ERR((void *)addr)) + return addr; + + err = __pkvm_create_mappings(addr, size, phys, prot); + if (err) + return (unsigned long)ERR_PTR(err); + + return addr + offset_in_page(phys); +} + int pkvm_create_mappings_locked(void *from, void *to, enum kvm_pgtable_prot prot) { unsigned long start = (unsigned long)from; @@ -152,10 +167,9 @@ int hyp_map_vectors(void) return 0; phys = __hyp_pa(__bp_harden_hyp_vecs); - bp_base = (void *)__pkvm_create_private_mapping(phys, - __BP_HARDEN_HYP_VECS_SZ, - PAGE_HYP_EXEC); - if (IS_ERR_OR_NULL(bp_base)) + bp_base = (void *)__pkvm_create_private_mapping(phys, __BP_HARDEN_HYP_VECS_SZ, + PAGE_SIZE, PAGE_HYP_EXEC); + if (IS_ERR(bp_base)) return PTR_ERR(bp_base); __hyp_bp_vect_base = bp_base; diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index a4868a6fa1c3..433c49766671 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -506,7 +506,7 @@ int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size, if (!kvm_host_owns_hyp_mappings()) { addr = kvm_call_hyp_nvhe(__pkvm_create_private_mapping, - phys_addr, size, prot); + phys_addr, size, align, prot); if (IS_ERR((void *)addr)) return PTR_ERR((void *)addr); *haddr = addr; -- 2.35.1.574.g5d30c73bfb-goog