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 E6179C433EF for ; Tue, 22 Feb 2022 16:53:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234382AbiBVQyT (ORCPT ); Tue, 22 Feb 2022 11:54:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33200 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232223AbiBVQyR (ORCPT ); Tue, 22 Feb 2022 11:54:17 -0500 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D017C38DB0 for ; Tue, 22 Feb 2022 08:53:51 -0800 (PST) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-2d07ae11462so146914547b3.8 for ; Tue, 22 Feb 2022 08:53:51 -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=HjTQZhkAd40lRuvS6cRV70Tpnwq9dG8Hrk7s02bufrw=; b=l9gvPlFOgpm93Vwqfc4x5Vuvn4H98TzVtnPztFKq1RVJHuCOwjRWnhPGwbxmv2gBju qni22+lZAoWeuHyAnrHLkUxmGVg1MGvOPtvysJUTpVnxGE9XNCgdGG3ihOcgDh4Ud0VO t81B3SWw8tC8AP32YUnfVl7SNtvpxpe1ER/dZExOrnQ3bwmGSIvoILXJpsKsbYOeEn5X eNRw3J9xbd+PwHflrNv9W7603a/Ig+5VqL31ZqaFq/h7ygZQBquGNSxpt5WNmcJEKeuh 799vMF4hFNUjwmMyaOlRkDXrCuhduGcEePOXQj+fAOq4j8VbFHa6wTIBzVfUzsaX0ujb tebQ== 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=HjTQZhkAd40lRuvS6cRV70Tpnwq9dG8Hrk7s02bufrw=; b=sDmp9dFDLdaEbcbHl9InkAEhhOi6yRb7QOGP9rnm8jFnRPUmzbGZ4EqLHtt2YA5B3H AaOAXxbklt0uq+dPQz1/H4odQlwuhssgIfheLLxRSKRWOBLsziuTPVJcIMLA4Eg/L3dF OZ0jiHPXxD4VGqtblYIm7IrdMTnVN3H0zP66iOGlNrF3Amyzcl8sAOvahjFpziRTBW/2 v0xcreuLo4e+ru5lrWUPPacsri8MMsyf1zrA8+X6nWiLOU9W+fvc4dVaFzXkybz6bXty kXSEViPhQWob010nq3Oy0iROvsiroAZUi1sievC6TeLrVve261xJ35/FXq6HB65h0wvg 6vLQ== X-Gm-Message-State: AOAM530aM1Dr3E0H6m6oJoECfbwRFna3UenUuSk8sc0EtKpziyWA/iJ2 JE3hUm0DHM+DZbYm5VWVZ8/ZFmjXrGokwVXGcw== X-Google-Smtp-Source: ABdhPJxqQdinLFWWaI+jsvW0KvgGVTkFzIldtere0/r0cpO5BgzuX/8Yyc3hdk7P6zZ0tb1mTeOyerwEEGUUJI16nw== X-Received: from kaleshsingh.mtv.corp.google.com ([2620:15c:211:200:5db7:1235:b3dd:cfcb]) (user=kaleshsingh job=sendgmr) by 2002:a25:4dd7:0:b0:621:a740:3988 with SMTP id a206-20020a254dd7000000b00621a7403988mr24600128ybb.58.1645548831008; Tue, 22 Feb 2022 08:53:51 -0800 (PST) Date: Tue, 22 Feb 2022 08:51:02 -0800 In-Reply-To: <20220222165212.2005066-1-kaleshsingh@google.com> Message-Id: <20220222165212.2005066-2-kaleshsingh@google.com> Mime-Version: 1.0 References: <20220222165212.2005066-1-kaleshsingh@google.com> X-Mailer: git-send-email 2.35.1.473.g83b2b277ed-goog Subject: [PATCH v2 1/9] KVM: arm64: Introduce hyp_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 , Catalin Marinas , James Morse , Alexandru Elisei , Suzuki K Poulose , Ard Biesheuvel , Mark Rutland , Pasha Tatashin , Joey Gouly , Peter Collingbourne , Andrew Walbran , Andrew Scull , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.cs.columbia.edu 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 hyp_alloc_private_va_range() can be used to reserve private VA ranges in the nVHE hypervisor. Also update __create_hyp_private_mapping() to allow specifying an alignment for the private VA mapping. These will be used to implement stack guard pages for KVM nVHE hypervisor (nVHE Hyp mode / not pKVM), in a subsequent patch in the series. Signed-off-by: Kalesh Singh --- arch/arm64/include/asm/kvm_mmu.h | 4 +++ arch/arm64/kvm/mmu.c | 61 +++++++++++++++++++++----------- 2 files changed, 44 insertions(+), 21 deletions(-) diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 81839e9a8a24..0b0c71302b92 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -153,6 +153,10 @@ static __always_inline unsigned long __kern_hyp_va(unsigned long v) int kvm_share_hyp(void *from, void *to); void kvm_unshare_hyp(void *from, void *to); int create_hyp_mappings(void *from, void *to, enum kvm_pgtable_prot prot); +unsigned long hyp_alloc_private_va_range(size_t size, size_t align); +int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size, + size_t align, unsigned long *haddr, + enum kvm_pgtable_prot prot); int create_hyp_io_mappings(phys_addr_t phys_addr, size_t size, void __iomem **kaddr, void __iomem **haddr); diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index bc2aba953299..e5abcce44ad0 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -457,22 +457,16 @@ int create_hyp_mappings(void *from, void *to, enum kvm_pgtable_prot prot) return 0; } -static int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size, - unsigned long *haddr, - enum kvm_pgtable_prot prot) + +/* + * Allocates a private VA range below io_map_base. + * + * @size: The size of the VA range to reserve. + * @align: The required alignment for the allocation. + */ +unsigned long hyp_alloc_private_va_range(size_t size, size_t align) { unsigned long base; - int ret = 0; - - if (!kvm_host_owns_hyp_mappings()) { - base = kvm_call_hyp_nvhe(__pkvm_create_private_mapping, - phys_addr, size, prot); - if (IS_ERR_OR_NULL((void *)base)) - return PTR_ERR((void *)base); - *haddr = base; - - return 0; - } mutex_lock(&kvm_hyp_pgd_mutex); @@ -484,8 +478,8 @@ static int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size, * * The allocated size is always a multiple of PAGE_SIZE. */ - size = PAGE_ALIGN(size + offset_in_page(phys_addr)); - base = io_map_base - size; + base = io_map_base - PAGE_ALIGN(size); + base = ALIGN_DOWN(base, align); /* * Verify that BIT(VA_BITS - 1) hasn't been flipped by @@ -493,20 +487,45 @@ static int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size, * overflowed the idmap/IO address range. */ if ((base ^ io_map_base) & BIT(VA_BITS - 1)) - ret = -ENOMEM; + base = (unsigned long)ERR_PTR(-ENOMEM); else io_map_base = base; mutex_unlock(&kvm_hyp_pgd_mutex); + return base; +} + +int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size, + size_t align, unsigned long *haddr, + enum kvm_pgtable_prot prot) +{ + unsigned long addr; + int ret = 0; + + if (!kvm_host_owns_hyp_mappings()) { + addr = kvm_call_hyp_nvhe(__pkvm_create_private_mapping, + phys_addr, size, prot); + if (IS_ERR_OR_NULL((void *)addr)) + return PTR_ERR((void *)addr); + *haddr = addr; + + return 0; + } + + size += offset_in_page(phys_addr); + addr = hyp_alloc_private_va_range(size, align); + if (IS_ERR_OR_NULL((void *)addr)) + return PTR_ERR((void *)addr); + if (ret) goto out; - ret = __create_hyp_mappings(base, size, phys_addr, prot); + ret = __create_hyp_mappings(addr, size, phys_addr, prot); if (ret) goto out; - *haddr = base + offset_in_page(phys_addr); + *haddr = addr + offset_in_page(phys_addr); out: return ret; } @@ -537,7 +556,7 @@ int create_hyp_io_mappings(phys_addr_t phys_addr, size_t size, return 0; } - ret = __create_hyp_private_mapping(phys_addr, size, + ret = __create_hyp_private_mapping(phys_addr, size, PAGE_SIZE, &addr, PAGE_HYP_DEVICE); if (ret) { iounmap(*kaddr); @@ -564,7 +583,7 @@ int create_hyp_exec_mappings(phys_addr_t phys_addr, size_t size, BUG_ON(is_kernel_in_hyp_mode()); - ret = __create_hyp_private_mapping(phys_addr, size, + ret = __create_hyp_private_mapping(phys_addr, size, PAGE_SIZE, &addr, PAGE_HYP_EXEC); if (ret) { *haddr = NULL; -- 2.35.1.473.g83b2b277ed-goog