From patchwork Mon Jul 6 02:56:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 11644841 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F050C92A for ; Mon, 6 Jul 2020 02:58:48 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CA86220747 for ; Mon, 6 Jul 2020 02:58:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="amOygU8v" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CA86220747 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:To: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=jEge/7MxkwLMIanD4fbrLiGDSF6Uj1e1w1+ZxLetMTs=; b=amOygU8vgGInzmnctqkNbAHjhB ghUGL6wM81O2S6lmYlpgDQMnIKaBXCe9tjTETELcz7o6+RsIfxwclJsZNIJas9lg61M9bRkC6qK1P hTMZ2GHwdtsTVliEFjknNfzd+7MhpqFXgerm4QgTNmE9h6uDpKZZvC/7vnLSnQG9HG1yy26gySVpv 36mx30BgLU+SpNOf6VHpa1938FZSL/JDDeg3WMSHf0dQy2hawCAev4I4u4dDe3Y8RDVgTV/ZO6aBQ sSeiZwHckNbWkLBgOH2ih46qVCwWQdB24yGGm+txqwhGIIHs/xkdf3lQPlZgfIIyGKAUzdrP6MQ0g loyGDgKQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jsHJn-0008KJ-Lx; Mon, 06 Jul 2020 02:57:19 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jsHJk-0008Ig-AK for linux-arm-kernel@lists.infradead.org; Mon, 06 Jul 2020 02:57:17 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 72752C0A; Sun, 5 Jul 2020 19:57:11 -0700 (PDT) Received: from p8cg001049571a15.arm.com (unknown [10.163.84.195]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 24CE73F71E; Sun, 5 Jul 2020 19:57:06 -0700 (PDT) From: Anshuman Khandual To: linux-mm@kvack.org Subject: [PATCH V4 3/3] arm64/mm: Enable vmem_altmap support for vmemmap mappings Date: Mon, 6 Jul 2020 08:26:18 +0530 Message-Id: <1594004178-8861-4-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1594004178-8861-1-git-send-email-anshuman.khandual@arm.com> References: <1594004178-8861-1-git-send-email-anshuman.khandual@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200705_225716_479794_21B8946C X-CRM114-Status: GOOD ( 16.36 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [217.140.110.172 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , justin.he@arm.com, Yu Zhao , Anshuman Khandual , catalin.marinas@arm.com, Steve Capper , David Hildenbrand , linux-kernel@vger.kernel.org, Hsin-Yi Wang , akpm@linux-foundation.org, Will Deacon , Thomas Gleixner , 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 Device memory ranges when getting hot added into ZONE_DEVICE, might require their vmemmap mapping's backing memory to be allocated from their own range instead of consuming system memory. This prevents large system memory usage for potentially large device memory ranges. Device driver communicates this request via vmem_altmap structure. Architecture needs to take this request into account while creating and tearing down vemmmap mappings. This enables vmem_altmap support in vmemmap_populate() and vmemmap_free() which includes vmemmap_populate_basepages() used for ARM64_16K_PAGES and ARM64_64K_PAGES configs. Cc: Catalin Marinas Cc: Will Deacon Cc: Mark Rutland Cc: Steve Capper Cc: David Hildenbrand Cc: Yu Zhao Cc: Hsin-Yi Wang Cc: Thomas Gleixner Cc: Andrew Morton Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Tested-by: Jia He Reviewed-by: Catalin Marinas Signed-off-by: Anshuman Khandual --- arch/arm64/mm/mmu.c | 58 +++++++++++++++++++++++++++++---------------- 1 file changed, 38 insertions(+), 20 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 9c08d1882106..51a1b0e886ff 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -760,15 +760,20 @@ int kern_addr_valid(unsigned long addr) } #ifdef CONFIG_MEMORY_HOTPLUG -static void free_hotplug_page_range(struct page *page, size_t size) +static void free_hotplug_page_range(struct page *page, size_t size, + struct vmem_altmap *altmap) { - WARN_ON(PageReserved(page)); - free_pages((unsigned long)page_address(page), get_order(size)); + if (altmap) { + vmem_altmap_free(altmap, size >> PAGE_SHIFT); + } else { + WARN_ON(PageReserved(page)); + free_pages((unsigned long)page_address(page), get_order(size)); + } } static void free_hotplug_pgtable_page(struct page *page) { - free_hotplug_page_range(page, PAGE_SIZE); + free_hotplug_page_range(page, PAGE_SIZE, NULL); } static bool pgtable_range_aligned(unsigned long start, unsigned long end, @@ -791,7 +796,8 @@ static bool pgtable_range_aligned(unsigned long start, unsigned long end, } static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr, - unsigned long end, bool free_mapped) + unsigned long end, bool free_mapped, + struct vmem_altmap *altmap) { pte_t *ptep, pte; @@ -805,12 +811,14 @@ static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr, pte_clear(&init_mm, addr, ptep); flush_tlb_kernel_range(addr, addr + PAGE_SIZE); if (free_mapped) - free_hotplug_page_range(pte_page(pte), PAGE_SIZE); + free_hotplug_page_range(pte_page(pte), + PAGE_SIZE, altmap); } while (addr += PAGE_SIZE, addr < end); } static void unmap_hotplug_pmd_range(pud_t *pudp, unsigned long addr, - unsigned long end, bool free_mapped) + unsigned long end, bool free_mapped, + struct vmem_altmap *altmap) { unsigned long next; pmd_t *pmdp, pmd; @@ -833,16 +841,17 @@ static void unmap_hotplug_pmd_range(pud_t *pudp, unsigned long addr, flush_tlb_kernel_range(addr, addr + PAGE_SIZE); if (free_mapped) free_hotplug_page_range(pmd_page(pmd), - PMD_SIZE); + PMD_SIZE, altmap); continue; } WARN_ON(!pmd_table(pmd)); - unmap_hotplug_pte_range(pmdp, addr, next, free_mapped); + unmap_hotplug_pte_range(pmdp, addr, next, free_mapped, altmap); } while (addr = next, addr < end); } static void unmap_hotplug_pud_range(p4d_t *p4dp, unsigned long addr, - unsigned long end, bool free_mapped) + unsigned long end, bool free_mapped, + struct vmem_altmap *altmap) { unsigned long next; pud_t *pudp, pud; @@ -865,16 +874,17 @@ static void unmap_hotplug_pud_range(p4d_t *p4dp, unsigned long addr, flush_tlb_kernel_range(addr, addr + PAGE_SIZE); if (free_mapped) free_hotplug_page_range(pud_page(pud), - PUD_SIZE); + PUD_SIZE, altmap); continue; } WARN_ON(!pud_table(pud)); - unmap_hotplug_pmd_range(pudp, addr, next, free_mapped); + unmap_hotplug_pmd_range(pudp, addr, next, free_mapped, altmap); } while (addr = next, addr < end); } static void unmap_hotplug_p4d_range(pgd_t *pgdp, unsigned long addr, - unsigned long end, bool free_mapped) + unsigned long end, bool free_mapped, + struct vmem_altmap *altmap) { unsigned long next; p4d_t *p4dp, p4d; @@ -887,16 +897,24 @@ static void unmap_hotplug_p4d_range(pgd_t *pgdp, unsigned long addr, continue; WARN_ON(!p4d_present(p4d)); - unmap_hotplug_pud_range(p4dp, addr, next, free_mapped); + unmap_hotplug_pud_range(p4dp, addr, next, free_mapped, altmap); } while (addr = next, addr < end); } static void unmap_hotplug_range(unsigned long addr, unsigned long end, - bool free_mapped) + bool free_mapped, struct vmem_altmap *altmap) { unsigned long next; pgd_t *pgdp, pgd; + /* + * altmap can only be used as vmemmap mapping backing memory. + * In case the backing memory itself is not being freed, then + * altmap is irrelevant. Warn about this inconsistency when + * encountered. + */ + WARN_ON(!free_mapped && altmap); + do { next = pgd_addr_end(addr, end); pgdp = pgd_offset_k(addr); @@ -905,7 +923,7 @@ static void unmap_hotplug_range(unsigned long addr, unsigned long end, continue; WARN_ON(!pgd_present(pgd)); - unmap_hotplug_p4d_range(pgdp, addr, next, free_mapped); + unmap_hotplug_p4d_range(pgdp, addr, next, free_mapped, altmap); } while (addr = next, addr < end); } @@ -1069,7 +1087,7 @@ static void free_empty_tables(unsigned long addr, unsigned long end, int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap) { - return vmemmap_populate_basepages(start, end, node, NULL); + return vmemmap_populate_basepages(start, end, node, altmap); } #else /* !ARM64_SWAPPER_USES_SECTION_MAPS */ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, @@ -1101,7 +1119,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, if (pmd_none(READ_ONCE(*pmdp))) { void *p = NULL; - p = vmemmap_alloc_block_buf(PMD_SIZE, node, NULL); + p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap); if (!p) return -ENOMEM; @@ -1119,7 +1137,7 @@ void vmemmap_free(unsigned long start, unsigned long end, #ifdef CONFIG_MEMORY_HOTPLUG WARN_ON((start < VMEMMAP_START) || (end > VMEMMAP_END)); - unmap_hotplug_range(start, end, true); + unmap_hotplug_range(start, end, true, altmap); free_empty_tables(start, end, VMEMMAP_START, VMEMMAP_END); #endif } @@ -1410,7 +1428,7 @@ static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size) WARN_ON(pgdir != init_mm.pgd); WARN_ON((start < PAGE_OFFSET) || (end > PAGE_END)); - unmap_hotplug_range(start, end, false); + unmap_hotplug_range(start, end, false, NULL); free_empty_tables(start, end, PAGE_OFFSET, PAGE_END); }