From patchwork Wed Dec 9 12:44:44 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Rutland X-Patchwork-Id: 7808231 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 5E59ABEEE1 for ; Wed, 9 Dec 2015 12:51:28 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 92F3C20527 for ; Wed, 9 Dec 2015 12:51:27 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7ADD72051F for ; Wed, 9 Dec 2015 12:51:26 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1a6eBL-0000oF-OF; Wed, 09 Dec 2015 12:49:19 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1a6e8O-0006XB-DW for linux-arm-kernel@lists.infradead.org; Wed, 09 Dec 2015 12:46:19 +0000 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 9BDAC5EF; Wed, 9 Dec 2015 04:45:33 -0800 (PST) Received: from leverpostej.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 F15E03F4FF; Wed, 9 Dec 2015 04:45:53 -0800 (PST) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Subject: [RFC PATCH 09/20] arm64: add function to install the idmap Date: Wed, 9 Dec 2015 12:44:44 +0000 Message-Id: <1449665095-20774-10-git-send-email-mark.rutland@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1449665095-20774-1-git-send-email-mark.rutland@arm.com> References: <1449665095-20774-1-git-send-email-mark.rutland@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151209_044616_629028_BCB6BD32 X-CRM114-Status: GOOD ( 10.67 ) X-Spam-Score: -6.9 (------) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, lorenzo.pieralisi@arm.com, arnd@arndb.de, ard.biesheuvel@linaro.org, andre.przywara@arm.com, will.deacon@arm.com, jeremy.linton@arm.com, catalin.marinas@arm.com, labbott@fedoraproject.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In some cases (e.g. when making invasive changes to the kernel page tables) we will need to execute code from the idmap. Add a new helper which may be used to install the idmap, complementing the existing cpu_uninstall_idmap. Signed-off-by: Mark Rutland Cc: Ard Biesheuvel Cc: Catalin Marinas Cc: Jeremy Linton Cc: Laura Abbott Cc: Will Deacon --- arch/arm64/include/asm/mmu_context.h | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h index b1b2514..944f273 100644 --- a/arch/arm64/include/asm/mmu_context.h +++ b/arch/arm64/include/asm/mmu_context.h @@ -74,7 +74,7 @@ static inline bool __cpu_uses_extended_idmap(void) /* * Set TCR.T0SZ to its default value (based on VA_BITS) */ -static inline void cpu_set_default_tcr_t0sz(void) +static inline void __cpu_set_tcr_t0sz(unsigned long t0sz) { unsigned long tcr; @@ -87,9 +87,12 @@ static inline void cpu_set_default_tcr_t0sz(void) " msr tcr_el1, %0 ;" " isb" : "=&r" (tcr) - : "r"(TCR_T0SZ(VA_BITS)), "I"(TCR_T0SZ_OFFSET), "I"(TCR_TxSZ_WIDTH)); + : "r"(t0sz), "I"(TCR_T0SZ_OFFSET), "I"(TCR_TxSZ_WIDTH)); } +#define cpu_set_default_tcr_t0sz() __cpu_set_tcr_t0sz(TCR_T0SZ(VA_BITS)) +#define cpu_set_idmap_tcr_t0sz() __cpu_set_tcr_t0sz(idmap_t0sz) + /* * Remove the idmap from TTBR0_EL1 and install the pgd of the active mm. * @@ -114,6 +117,15 @@ static inline void cpu_uninstall_idmap(void) cpu_switch_mm(mm->pgd, mm); } +static inline void cpu_install_idmap(void) +{ + cpu_set_reserved_ttbr0(); + local_flush_tlb_all(); + cpu_set_idmap_tcr_t0sz(); + + cpu_switch_mm(idmap_pg_dir, &init_mm); +} + /* * It would be nice to return ASIDs back to the allocator, but unfortunately * that introduces a race with a generation rollover where we could erroneously