From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1326FC432BE for ; Thu, 12 Aug 2021 23:39:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E653E6108C for ; Thu, 12 Aug 2021 23:39:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238737AbhHLXjW (ORCPT ); Thu, 12 Aug 2021 19:39:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:49068 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238496AbhHLXib (ORCPT ); Thu, 12 Aug 2021 19:38:31 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D23A661101; Thu, 12 Aug 2021 23:38:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628811486; bh=VGtZCbKljVwjXPskC+/bFDWf9l1SbMAK3xd6joWYr3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dh3f/J/QQ5q0R8A4sxpCNodX8JWCbztZwgSkoR0mwiE1JPB3LjQhc4rHCOFvEsFUz Z0gRIJyWG38cuR4CyMOXJ6fdZ/Z3i2B1XJe3FVGhSYklCqrtLWcz2tms1tFmgLaczJ mmiKZdQWV7pRKUAJnkYDnGyvX1O0uwRdkBE+UG/WvEMeT30FMXroO0s914EwJdn12t 5MCEQm4i53THfTpslaFBf1snNLHe/Snr1vKnHWhQHYYrXW/zhaFJzoKGEAVWceKe6+ n2PMoIx0/vvIIGG+vrxMJtKA3bIomvupXvJ4UwiQn7/orvyqUt+lx/uBX09r9Jyjvj kVgvrQGf1V30g== From: Vineet Gupta To: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Anshuman Khandual , Mike Rapoport , Vineet Gupta Subject: [PATCH v2 19/19] ARC: mm: introduce _PAGE_TABLE to explicitly link pgd,pud,pmd entries Date: Thu, 12 Aug 2021 16:37:53 -0700 Message-Id: <20210812233753.104217-20-vgupta@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210812233753.104217-1-vgupta@kernel.org> References: <20210812233753.104217-1-vgupta@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ARCv3 hardware walker expects Table Descriptors to have b'11 in LSB bits to continue moving to next level. This commits adds that (to ARCv2 code) and ensures that it works in software walked regime. The pte entries stil need tagging, but that is not possible in ARCv2 since the LSB 2 bits are currently used. Signed-off-by: Vineet Gupta --- arch/arc/include/asm/pgalloc.h | 8 ++++---- arch/arc/include/asm/pgtable-bits-arcv2.h | 2 ++ arch/arc/include/asm/pgtable-levels.h | 6 +++--- arch/arc/mm/tlbex.S | 4 +++- 4 files changed, 12 insertions(+), 8 deletions(-) diff --git a/arch/arc/include/asm/pgalloc.h b/arch/arc/include/asm/pgalloc.h index 096b8ef58edb..a8c01eceba1b 100644 --- a/arch/arc/include/asm/pgalloc.h +++ b/arch/arc/include/asm/pgalloc.h @@ -43,12 +43,12 @@ pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte) * * The cast itself is needed given simplistic definition of set_pmd() */ - set_pmd(pmd, __pmd((unsigned long)pte)); + set_pmd(pmd, __pmd((unsigned long)pte | _PAGE_TABLE)); } static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, pgtable_t pte_page) { - set_pmd(pmd, __pmd((unsigned long)page_address(pte_page))); + set_pmd(pmd, __pmd((unsigned long)page_address(pte_page) | _PAGE_TABLE)); } static inline pgd_t *pgd_alloc(struct mm_struct *mm) @@ -74,7 +74,7 @@ static inline pgd_t *pgd_alloc(struct mm_struct *mm) static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4dp, pud_t *pudp) { - set_p4d(p4dp, __p4d((unsigned long)pudp)); + set_p4d(p4dp, __p4d((unsigned long)pudp | _PAGE_TABLE)); } #define __pud_free_tlb(tlb, pmd, addr) pud_free((tlb)->mm, pmd) @@ -85,7 +85,7 @@ static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4dp, pud_t *pudp) static inline void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmdp) { - set_pud(pudp, __pud((unsigned long)pmdp)); + set_pud(pudp, __pud((unsigned long)pmdp | _PAGE_TABLE)); } #define __pmd_free_tlb(tlb, pmd, addr) pmd_free((tlb)->mm, pmd) diff --git a/arch/arc/include/asm/pgtable-bits-arcv2.h b/arch/arc/include/asm/pgtable-bits-arcv2.h index 183d23bc1e00..54aba0d3ae34 100644 --- a/arch/arc/include/asm/pgtable-bits-arcv2.h +++ b/arch/arc/include/asm/pgtable-bits-arcv2.h @@ -32,6 +32,8 @@ #define _PAGE_HW_SZ 0 #endif +#define _PAGE_TABLE 0x3 + /* Defaults for every user page */ #define ___DEF (_PAGE_PRESENT | _PAGE_CACHEABLE) diff --git a/arch/arc/include/asm/pgtable-levels.h b/arch/arc/include/asm/pgtable-levels.h index 2da3c4e52a91..6c7a8360d986 100644 --- a/arch/arc/include/asm/pgtable-levels.h +++ b/arch/arc/include/asm/pgtable-levels.h @@ -98,7 +98,7 @@ /* In 4 level paging, p4d_* macros work on pgd */ #define p4d_none(x) (!p4d_val(x)) -#define p4d_bad(x) ((p4d_val(x) & ~PAGE_MASK)) +#define p4d_bad(x) (!(p4d_val(x) & _PAGE_TABLE)) #define p4d_present(x) (p4d_val(x)) #define p4d_clear(xp) do { p4d_val(*(xp)) = 0; } while (0) #define p4d_pgtable(p4d) ((pud_t *)(p4d_val(p4d) & PAGE_MASK)) @@ -120,7 +120,7 @@ * In 4 level paging, pud_* macros work on pud */ #define pud_none(x) (!pud_val(x)) -#define pud_bad(x) ((pud_val(x) & ~PAGE_MASK)) +#define pud_bad(x) (!(pud_val(x) & _PAGE_TABLE)) #define pud_present(x) (pud_val(x)) #define pud_clear(xp) do { pud_val(*(xp)) = 0; } while (0) #define pud_pgtable(pud) ((pmd_t *)(pud_val(pud) & PAGE_MASK)) @@ -147,7 +147,7 @@ * In 3+ level paging (pgd -> pmd -> pte), pmd_* macros work on pmd */ #define pmd_none(x) (!pmd_val(x)) -#define pmd_bad(x) ((pmd_val(x) & ~PAGE_MASK)) +#define pmd_bad(pmd) (!(pmd_val(pmd) & _PAGE_TABLE)) #define pmd_present(x) (pmd_val(x)) #define pmd_clear(xp) do { pmd_val(*(xp)) = 0; } while (0) #define pmd_page_vaddr(pmd) (pmd_val(pmd) & PAGE_MASK) diff --git a/arch/arc/mm/tlbex.S b/arch/arc/mm/tlbex.S index e054780a8fe0..3874a8086591 100644 --- a/arch/arc/mm/tlbex.S +++ b/arch/arc/mm/tlbex.S @@ -171,11 +171,12 @@ ex_saved_reg1: lsr r0, r2, PGDIR_SHIFT ; Bits for indexing into PGD ld.as r3, [r1, r0] ; PGD entry corresp to faulting addr tst r3, r3 - bz do_slow_path_pf ; if no Page Table, do page fault + bz do_slow_path_pf ; next level table missing, handover to linux vm code #if CONFIG_PGTABLE_LEVELS > 3 lsr r0, r2, PUD_SHIFT ; Bits for indexing into PUD and r0, r0, (PTRS_PER_PUD - 1) + bmskn r3, r3, 1 ; clear _PAGE_TABLE bits ld.as r1, [r3, r0] ; PMD entry tst r1, r1 bz do_slow_path_pf @@ -185,6 +186,7 @@ ex_saved_reg1: #if CONFIG_PGTABLE_LEVELS > 2 lsr r0, r2, PMD_SHIFT ; Bits for indexing into PMD and r0, r0, (PTRS_PER_PMD - 1) + bmskn r3, r3, 1 ; clear _PAGE_TABLE bits ld.as r1, [r3, r0] ; PMD entry tst r1, r1 bz do_slow_path_pf -- 2.25.1