From patchwork Wed Dec 9 12:44:52 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Rutland X-Patchwork-Id: 7808271 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 503F7BEEE1 for ; Wed, 9 Dec 2015 12:53:28 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 77D742051F for ; Wed, 9 Dec 2015 12:53:27 +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 5EA402051D for ; Wed, 9 Dec 2015 12:53:26 +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 1a6eDL-00042i-W9; Wed, 09 Dec 2015 12:51:24 +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-0006Um-NT for linux-arm-kernel@lists.infradead.org; Wed, 09 Dec 2015 12:46:24 +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 E6DE2600; Wed, 9 Dec 2015 04:45:52 -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 496A73F4FF; Wed, 9 Dec 2015 04:46:13 -0800 (PST) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Subject: [RFC PATCH 17/20] arm64: mm: allocate pagetables anywhere Date: Wed, 9 Dec 2015 12:44:52 +0000 Message-Id: <1449665095-20774-18-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_044617_089356_B0892E70 X-CRM114-Status: GOOD ( 11.67 ) 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 Now that create_mapping uses fixmap slots to modify pte, pmd, and pud entries, we can access page tables anywhere in physical memory, regardless of the extent of the linear mapping. Given that, we no longer need to limit memblock allocations during page table creation, and can leave the limit as its default MEMBLOCK_ALLOC_ANYWHERE. We never add memory which will fall outside of the linear map range given phys_offset and MAX_MEMBLOCK_ADDR are configured appropriately, so any tables we create will fall in the linear map of the final tables. Signed-off-by: Mark Rutland Cc: Ard Biesheuvel Cc: Catalin Marinas Cc: Jeremy Linton Cc: Laura Abbott Cc: Will Deacon --- arch/arm64/mm/mmu.c | 35 ----------------------------------- 1 file changed, 35 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 1a516ac..27dd475 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -365,20 +365,6 @@ static void __init __map_memblock(phys_addr_t start, phys_addr_t end) static void __init map_mem(void) { struct memblock_region *reg; - phys_addr_t limit; - - /* - * Temporarily limit the memblock range. We need to do this as - * create_mapping requires puds, pmds and ptes to be allocated from - * memory addressable from the initial direct kernel mapping. - * - * The initial direct kernel mapping, located at swapper_pg_dir, gives - * us PUD_SIZE (with SECTION maps) or PMD_SIZE (without SECTION maps, - * memory starting from PHYS_OFFSET (which must be aligned to 2MB as - * per Documentation/arm64/booting.txt). - */ - limit = PHYS_OFFSET + SWAPPER_INIT_MAP_SIZE; - memblock_set_current_limit(limit); /* map all the memory banks */ for_each_memblock(memory, reg) { @@ -388,29 +374,8 @@ static void __init map_mem(void) if (start >= end) break; - if (ARM64_SWAPPER_USES_SECTION_MAPS) { - /* - * For the first memory bank align the start address and - * current memblock limit to prevent create_mapping() from - * allocating pte page tables from unmapped memory. With - * the section maps, if the first block doesn't end on section - * size boundary, create_mapping() will try to allocate a pte - * page, which may be returned from an unmapped area. - * When section maps are not used, the pte page table for the - * current limit is already present in swapper_pg_dir. - */ - if (start < limit) - start = ALIGN(start, SECTION_SIZE); - if (end < limit) { - limit = end & SECTION_MASK; - memblock_set_current_limit(limit); - } - } __map_memblock(start, end); } - - /* Limit no longer required. */ - memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE); } static void __init fixup_executable(void)