From patchwork Wed Dec 28 04:35:25 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: AKASHI Takahiro X-Patchwork-Id: 9489961 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9F51462AB0 for ; Wed, 28 Dec 2016 04:37:01 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7673A1FF65 for ; Wed, 28 Dec 2016 04:37:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6B1882094F; Wed, 28 Dec 2016 04:37:01 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID autolearn=ham version=3.3.1 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.wl.linuxfoundation.org (Postfix) with ESMTPS id 049951FF65 for ; Wed, 28 Dec 2016 04:37:01 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1cM5xm-0005kN-Ls; Wed, 28 Dec 2016 04:35:42 +0000 Received: from mail-pg0-x234.google.com ([2607:f8b0:400e:c05::234]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1cM5xd-0004nE-LI for linux-arm-kernel@lists.infradead.org; Wed, 28 Dec 2016 04:35:35 +0000 Received: by mail-pg0-x234.google.com with SMTP id y62so99556109pgy.1 for ; Tue, 27 Dec 2016 20:35:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=n2GMTdbaOY/o8gawJV6bJ+j0wSoAToAO7G2wpqdfMno=; b=EM+KgOpfeZ7psamOFthU47bW+deFovO6ys4lsc2pEAA4+J6BfqkWBhSTNOEfaPK3BA JtbCKhhXcZheH5X4r9yKyVmTOLVMA6pPY/8kisggIrFfTCmq7hj/Kug7l9HNrOlcgrX8 pENEED/hj77k6zFA0e6SMUR9MN4wsu5iq9TVM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=n2GMTdbaOY/o8gawJV6bJ+j0wSoAToAO7G2wpqdfMno=; b=odWrqyGQmUBtSFbnLRcxxOK+fJ0B+1H2UhZVmnQs0rVpnkeNOChjf1F+0r+NhnW3w7 tu5EsaWOkvVRGsCQ4ENip3+GcGaOKq2xSoAQOUxSHay7WD+61Str7/s9UX1VIxEJpaul qGDDU2QhAHQOC5aeG5qv0JnjG/io67l7Il4Vc/kQVUFKsM+AfNAjK624ulXAfTY2N3NN uzHwIGE9AGR0j+hnxsisBNMkrQcBRcrj+/ozCjdv+v+0yg1YQy4BU3i34t4w0OpAw1VS +Y6GX8xbd8DI5umHyEqkK8TWJ35pJdhdXEsSWc16c8f7MlNXqvwG9rsAXkbZOpafwoq9 MZIw== X-Gm-Message-State: AIkVDXLUQmrY8AAsWUx+Bfg4eg9NjhZkn6kRyIFVQxabZy15/jbfdOeKFZ7/cLW92nyR+sJF X-Received: by 10.99.122.17 with SMTP id v17mr60713931pgc.31.1482899710054; Tue, 27 Dec 2016 20:35:10 -0800 (PST) Received: from linaro.org ([121.95.100.191]) by smtp.googlemail.com with ESMTPSA id j68sm92780285pfk.95.2016.12.27.20.35.09 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 27 Dec 2016 20:35:09 -0800 (PST) From: AKASHI Takahiro To: catalin.marinas@arm.com, will.deacon@arm.com, akpm@linux-foundation.org Subject: [PATCH v29 1/9] memblock: add memblock_cap_memory_range() Date: Wed, 28 Dec 2016 13:35:25 +0900 Message-Id: <20161228043525.27420-1-takahiro.akashi@linaro.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20161228043347.27358-1-takahiro.akashi@linaro.org> References: <20161228043347.27358-1-takahiro.akashi@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20161227_203533_743453_72D6850C X-CRM114-Status: GOOD ( 14.61 ) 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, AKASHI Takahiro , geoff@infradead.org, kexec@lists.infradead.org, linux-mm@kvack.org, james.morse@arm.com, bauerman@linux.vnet.ibm.com, dyoung@redhat.com, linux-arm-kernel@lists.infradead.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-Virus-Scanned: ClamAV using ClamSMTP Add memblock_cap_memory_range() which will remove all the memblock regions except the memory range specified in the arguments. In addition, rework is done on memblock_mem_limit_remove_map() to re-implement it using memblock_cap_memory_range(). This function, like memblock_mem_limit_remove_map(), will not remove memblocks with MEMMAP_NOMAP attribute as they may be mapped and accessed later as "device memory." See the commit a571d4eb55d8 ("mm/memblock.c: add new infrastructure to address the mem limit issue"). This function is used, in a succeeding patch in the series of arm64 kdump suuport, to limit the range of usable memory, or System RAM, on crash dump kernel. (Please note that "mem=" parameter is of little use for this purpose.) Signed-off-by: AKASHI Takahiro Reviewed-by: Will Deacon Acked-by: Catalin Marinas Cc: linux-mm@kvack.org Cc: Andrew Morton Acked-by: Dennis Chen --- include/linux/memblock.h | 1 + mm/memblock.c | 44 +++++++++++++++++++++++++++++--------------- 2 files changed, 30 insertions(+), 15 deletions(-) diff --git a/include/linux/memblock.h b/include/linux/memblock.h index 5b759c9acf97..fbfcacc50c29 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -333,6 +333,7 @@ phys_addr_t memblock_mem_size(unsigned long limit_pfn); phys_addr_t memblock_start_of_DRAM(void); phys_addr_t memblock_end_of_DRAM(void); void memblock_enforce_memory_limit(phys_addr_t memory_limit); +void memblock_cap_memory_range(phys_addr_t base, phys_addr_t size); void memblock_mem_limit_remove_map(phys_addr_t limit); bool memblock_is_memory(phys_addr_t addr); int memblock_is_map_memory(phys_addr_t addr); diff --git a/mm/memblock.c b/mm/memblock.c index 7608bc305936..fea1688fef60 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -1514,11 +1514,37 @@ void __init memblock_enforce_memory_limit(phys_addr_t limit) (phys_addr_t)ULLONG_MAX); } +void __init memblock_cap_memory_range(phys_addr_t base, phys_addr_t size) +{ + int start_rgn, end_rgn; + int i, ret; + + if (!size) + return; + + ret = memblock_isolate_range(&memblock.memory, base, size, + &start_rgn, &end_rgn); + if (ret) + return; + + /* remove all the MAP regions */ + for (i = memblock.memory.cnt - 1; i >= end_rgn; i--) + if (!memblock_is_nomap(&memblock.memory.regions[i])) + memblock_remove_region(&memblock.memory, i); + + for (i = start_rgn - 1; i >= 0; i--) + if (!memblock_is_nomap(&memblock.memory.regions[i])) + memblock_remove_region(&memblock.memory, i); + + /* truncate the reserved regions */ + memblock_remove_range(&memblock.reserved, 0, base); + memblock_remove_range(&memblock.reserved, + base + size, (phys_addr_t)ULLONG_MAX); +} + void __init memblock_mem_limit_remove_map(phys_addr_t limit) { - struct memblock_type *type = &memblock.memory; phys_addr_t max_addr; - int i, ret, start_rgn, end_rgn; if (!limit) return; @@ -1529,19 +1555,7 @@ void __init memblock_mem_limit_remove_map(phys_addr_t limit) if (max_addr == (phys_addr_t)ULLONG_MAX) return; - ret = memblock_isolate_range(type, max_addr, (phys_addr_t)ULLONG_MAX, - &start_rgn, &end_rgn); - if (ret) - return; - - /* remove all the MAP regions above the limit */ - for (i = end_rgn - 1; i >= start_rgn; i--) { - if (!memblock_is_nomap(&type->regions[i])) - memblock_remove_region(type, i); - } - /* truncate the reserved regions */ - memblock_remove_range(&memblock.reserved, max_addr, - (phys_addr_t)ULLONG_MAX); + memblock_cap_memory_range(0, max_addr); } static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)