From patchwork Fri Nov 17 18:21:51 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 119207 Delivered-To: patch@linaro.org Received: by 10.140.22.164 with SMTP id 33csp846535qgn; Fri, 17 Nov 2017 10:25:37 -0800 (PST) X-Google-Smtp-Source: AGs4zMZ/x3HTxwKSQeB05J3HtzjSvE0YqAaDfMRAdiWsv/5/necJmGE8nUuNOHpKkpwW1zDO24wy X-Received: by 10.99.142.73 with SMTP id k70mr6017406pge.426.1510943137821; Fri, 17 Nov 2017 10:25:37 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1510943137; cv=none; d=google.com; s=arc-20160816; b=lrVPBp77ZjVURrk6GUSmgRGYgnjOUvrZKxSSGFgc028Kg1cz32mNS3pG/QSbsWTtcS UpD4I64akFEHZSwIB8nslhRvlIQ8N3fMOEbzUxkrXL/O3mD2/LYima8qkG1p+UscqQla 3L22qAzQCJ9Tubxc5CVHNTyD++LwCdAWy9S4MoOYeHQqWilfL/enRB69BVW1a6t7dvaw Ar4O+VPDQbvPWmIuQfMPNQnKkw1/HnLQU6Z3ovQNvUCjKGpSADtEw/yaiFpJI2mTfOWu rd0qdgNcKKvvqkF9vrzJrEgEVWcqsuI+mUUQsYtWQAgh/fuzsHHmubpUHeNKPN1zqjCJ fVSg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=uscVK/pF4fgLrK54hpEJVm83yG7CHNfeg3AmEAcmx0w=; b=RG6zQr5eYpJ0jtHSJVQqECwl+H3CdVaF22tSQ+nmHLhEZsI0lx8KkSK5ZlnjoDpt3X 2KOT0V+nes7m/b5F/T2tLlHo9oWj+KJpIYF4Qw71e0I2WxHh8VvzY0X1wt6ol5y6RPnY qHoQOo+fsgWNB7SEpbAgjc8hImf+EpDgiKCSClz2RU8obwXjgcE2JvITujCKWamaTmyH LBpE7hizctH1zIuIkBOjsHCynva6TWZ0K+Pl++/qMLZ+hjL/TZ7OqJHRhRUuCk58Xkdw o8/Jo5pGyRwEil9cIZ2TYwwqNCzLMpk+NCuyThcmEVusiHEZ5MKqU7C13YjKkF39giW2 WdMA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id 64si3169904plk.227.2017.11.17.10.25.37; Fri, 17 Nov 2017 10:25:37 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760577AbdKQSZe (ORCPT + 28 others); Fri, 17 Nov 2017 13:25:34 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:39452 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760288AbdKQSV4 (ORCPT ); Fri, 17 Nov 2017 13:21:56 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0EB27169F; Fri, 17 Nov 2017 10:21:55 -0800 (PST) Received: from edgewater-inn.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id D4F3F3F703; Fri, 17 Nov 2017 10:21:54 -0800 (PST) Received: by edgewater-inn.cambridge.arm.com (Postfix, from userid 1000) id 5CCF41AE1361; Fri, 17 Nov 2017 18:22:03 +0000 (GMT) From: Will Deacon To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, ard.biesheuvel@linaro.org, sboyd@codeaurora.org, dave.hansen@linux.intel.com, keescook@chromium.org, Will Deacon Subject: [PATCH 08/18] arm64: mm: Add arm64_kernel_mapped_at_el0 helper using static key Date: Fri, 17 Nov 2017 18:21:51 +0000 Message-Id: <1510942921-12564-9-git-send-email-will.deacon@arm.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1510942921-12564-1-git-send-email-will.deacon@arm.com> References: <1510942921-12564-1-git-send-email-will.deacon@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In order for code such as TLB invalidation to operate efficiently when the decision to map the kernel at EL0 is determined at runtime, this patch introduces a helper function, arm64_kernel_mapped_at_el0, which uses a static key that will later be hooked up to a command-line option. Signed-off-by: Will Deacon --- arch/arm64/include/asm/mmu.h | 11 +++++++++++ arch/arm64/mm/mmu.c | 5 +++++ 2 files changed, 16 insertions(+) -- 2.1.4 diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h index 01bfb184f2a8..a84f851409ca 100644 --- a/arch/arm64/include/asm/mmu.h +++ b/arch/arm64/include/asm/mmu.h @@ -19,6 +19,8 @@ #define MMCF_AARCH32 0x1 /* mm context flag for AArch32 executables */ #define USER_ASID_FLAG (UL(1) << 48) +#ifndef __ASSEMBLY__ + typedef struct { atomic64_t id; void *vdso; @@ -32,6 +34,14 @@ typedef struct { */ #define ASID(mm) ((mm)->context.id.counter & 0xffff) +DECLARE_STATIC_KEY_TRUE(__unmap_kernel_at_el0); + +static inline bool arm64_kernel_mapped_at_el0(void) +{ + return !IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0) || + !static_branch_likely(&__unmap_kernel_at_el0); +} + extern void paging_init(void); extern void bootmem_init(void); extern void __iomem *early_io_map(phys_addr_t phys, unsigned long virt); @@ -42,4 +52,5 @@ extern void create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, extern void *fixmap_remap_fdt(phys_addr_t dt_phys); extern void mark_linear_text_alias_ro(void); +#endif /* !__ASSEMBLY__ */ #endif diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index f1eb15e0e864..a75858267b6d 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -525,6 +525,11 @@ static int __init parse_rodata(char *arg) } early_param("rodata", parse_rodata); +#ifdef CONFIG_UNMAP_KERNEL_AT_EL0 +DEFINE_STATIC_KEY_TRUE(__unmap_kernel_at_el0); +EXPORT_SYMBOL_GPL(__unmap_kernel_at_el0); +#endif + /* * Create fine-grained mappings for the kernel. */