From patchwork Mon May 1 19:27:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vishal Moola X-Patchwork-Id: 13228325 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 601C4C77B73 for ; Mon, 1 May 2023 20:40:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=5/2KosVp//rvAlHZUOTAY+3QnJT2cg0kqdd7j8Ua2nw=; b=IlRbkeWhjbOK2e ucBN5EdbHIkXDGsXiU4ioQZXEUoISZqS5fnFHH6y5cLdVPgcl0ujkD/MA/KPTCGZKvXBfc6jk2Lq7 DlYg5pNp9ISX1lj672eIiBKW3EdM0H7oi9sVBbjKrvGMwu1ZfnOrk27OtC4Jc/mAdo7J1Fr8TFBwu I/4LDDKi+3Q/uH1zbPkSm8eDdWv4R3Qb/nXbKBx3mQKoCXMWLzSLPS2x0/vAeOF+WRfRiXOpOOwr2 AD9JMTle3p2XMJcjRkhfl9k7fEdP0GoL7iT2iv54UXAEnMTe2X2EOjPscCv06WCN+bSttRmk1oBw7 065KenRIcb1uv9DZU/zQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1ptaKA-00GuCC-2k; Mon, 01 May 2023 20:40:42 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1ptaK6-00Gu62-1G; Mon, 01 May 2023 20:40:38 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Transfer-Encoding:MIME-Version :References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=B0Od9Inc5y6h3dSbsHmdGR20xSLs7HxIKZ/fFcl7OHg=; b=Z/EqDqOL6QBL9G5oboeFvVGM50 Ncp3dQHt9Bqhw/cmd9GA3dCaCUo3PTAiYYENMw+p2L0ivTClZeu2Qv2pmrEjcTvVA+0jZ1gkxsHDI Sz0+BYMwd8SIbBeg1rQaFrBqPkRBMas7+KZ+ILmtZxNi5ZpS4oK6U5sDm28hxrAQeR1Q6SkyF46Xl FnRU1o8zuo3ofwoVYe6G1FbY+BBfimMGtr8U8AR8287QAQkvwpSsumraWQNTYAlEUD6aGEpG4btSu VWc238yiEfe4HLnixOMyCmbPdB99s2g7T1MIWHttVkYIZjrEMq2N0f79g80//GPoKQbOWFicOzZek lthZ+6hg==; Received: from mail-pf1-x42d.google.com ([2607:f8b0:4864:20::42d]) by desiato.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1ptZCV-00Eyyu-2u; Mon, 01 May 2023 19:28:46 +0000 Received: by mail-pf1-x42d.google.com with SMTP id d2e1a72fcca58-63f273b219eso2047907b3a.1; Mon, 01 May 2023 12:28:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1682969320; x=1685561320; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=B0Od9Inc5y6h3dSbsHmdGR20xSLs7HxIKZ/fFcl7OHg=; b=BSfSX498+nRsOwkOZCv/c3TfiIzHvFrBHqOPXzZnUzdOTpraA1SFYJQ7S9OlNSy+oo SgKJwDZ3qC6C//XEAcYljRcEjgHnyeaNoyhEAyOx7Ys6/3k09Ik8CgCQWIiXukHyuWI8 JqooqMgdLQ1gpcR/L/mcYK+KZEjEg+InGInQqZs8g+xQwi3fiMtnPj+o8uf54dHCG0nD x8PpX8tpE3nfYMsr6vBPGSrBk7IqcdW9rAQJxVfKMF33+mjDorfNig4J/P1XioZbWwxD uXByeI5tsaD8qrYP2W7mncKrp6aQydR1tjw1T6sz0jLjo8cvDXE3/58iahOtRXOU+sGT jXsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1682969320; x=1685561320; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=B0Od9Inc5y6h3dSbsHmdGR20xSLs7HxIKZ/fFcl7OHg=; b=ZkDYCetij0LBFAy7VQLShTxaJ56u6GXoapb/LjlRjktqgWPOoC1z+rCVXGbTpWBecy HEPb6CF8y95qpj+S3lDkzGOdWVr57wlUq+9f0E2CUsikebXI4CBZTNM31mVbOof/MOdR zHJHd6QLftdoLG3D+PMd61I3EFRH/wG1fLWM2uVnkXN54r65Lziojb1VAuHOoO+f1Bh8 I37Wkmogl9l76eUb8T9Ey84jj2CmBFPnUs9Hka/3NMwT7LBl9Qxa1cEY7XMbShcoyj50 igSjFDQHchlKZMXAIj6KGMjon5oCef8Ftt++8rXzB0WVOWSUaJY96WpDua2sNEAg56Cr 55/A== X-Gm-Message-State: AC+VfDxzTFBLLWeTEAfy+r7Xec5nIx0CnuP5JShkcecKmi6xJIFUG/fT 6L6Ox9vmk5CxXiOA5tVWlPfdIu/6JCnGKCXm X-Google-Smtp-Source: ACHHUZ5c/2Ko6MMnlJILdIHFSiqsi7woH2pp9LXJUwyBETBH//ZWHg6e+tUlm1aX3nzTckKQE2QL/Q== X-Received: by 2002:a17:902:d2cf:b0:1aa:ffe1:de13 with SMTP id n15-20020a170902d2cf00b001aaffe1de13mr2810716plc.5.1682969320162; Mon, 01 May 2023 12:28:40 -0700 (PDT) Received: from fedora.hsd1.ca.comcast.net ([2601:644:937f:7f20::9a2c]) by smtp.googlemail.com with ESMTPSA id u8-20020a170902bf4800b0019c13d032d8sm18175622pls.253.2023.05.01.12.28.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 01 May 2023 12:28:39 -0700 (PDT) From: "Vishal Moola (Oracle)" To: Andrew Morton , Matthew Wilcox Cc: linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, loongarch@lists.linux.dev, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, xen-devel@lists.xenproject.org, kvm@vger.kernel.org, "Vishal Moola (Oracle)" Subject: [PATCH v2 04/34] pgtable: Create struct ptdesc Date: Mon, 1 May 2023 12:27:59 -0700 Message-Id: <20230501192829.17086-5-vishal.moola@gmail.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230501192829.17086-1-vishal.moola@gmail.com> References: <20230501192829.17086-1-vishal.moola@gmail.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230501_202844_293587_7C7855C8 X-CRM114-Status: GOOD ( 11.56 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Currently, page table information is stored within struct page. As part of simplifying struct page, create struct ptdesc for page table information. Signed-off-by: Vishal Moola (Oracle) --- include/linux/pgtable.h | 52 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 023918666dd4..5e0f51308724 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -989,6 +989,58 @@ static inline void ptep_modify_prot_commit(struct vm_area_struct *vma, #endif /* __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION */ #endif /* CONFIG_MMU */ + +/** + * struct ptdesc - Memory descriptor for page tables. + * @__page_flags: Same as page flags. Unused for page tables. + * @pt_list: List of used page tables. Used for s390 and x86. + * @_pt_pad_1: Padding that aliases with page's compound head. + * @pmd_huge_pte: Protected by ptdesc->ptl, used for THPs. + * @_pt_s390_gaddr: Aliases with page's mapping. Used for s390 gmap only. + * @pt_mm: Used for x86 pgds. + * @pt_frag_refcount: For fragmented page table tracking. Powerpc and s390 only. + * @ptl: Lock for the page table. + * + * This struct overlays struct page for now. Do not modify without a good + * understanding of the issues. + */ +struct ptdesc { + unsigned long __page_flags; + + union { + struct list_head pt_list; + struct { + unsigned long _pt_pad_1; + pgtable_t pmd_huge_pte; + }; + }; + unsigned long _pt_s390_gaddr; + + union { + struct mm_struct *pt_mm; + atomic_t pt_frag_refcount; + unsigned long index; + }; + +#if ALLOC_SPLIT_PTLOCKS + spinlock_t *ptl; +#else + spinlock_t ptl; +#endif +}; + +#define TABLE_MATCH(pg, pt) \ + static_assert(offsetof(struct page, pg) == offsetof(struct ptdesc, pt)) +TABLE_MATCH(flags, __page_flags); +TABLE_MATCH(compound_head, pt_list); +TABLE_MATCH(compound_head, _pt_pad_1); +TABLE_MATCH(pmd_huge_pte, pmd_huge_pte); +TABLE_MATCH(mapping, _pt_s390_gaddr); +TABLE_MATCH(pt_mm, pt_mm); +TABLE_MATCH(ptl, ptl); +#undef TABLE_MATCH +static_assert(sizeof(struct ptdesc) <= sizeof(struct page)); + /* * No-op macros that just return the current protection value. Defined here * because these macros can be used even if CONFIG_MMU is not defined.