From patchwork Thu Aug 12 23:37:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vineet Gupta X-Patchwork-Id: 1516482 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; secure) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=OakDBBcF; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=isKycoi2; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4Gm3630vh7z9t6S for ; Fri, 13 Aug 2021 09:38:18 +1000 (AEST) 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=kSjROh2y2J8AGAmMdRhoaKiWKQCNkgc0Wl15TPhKp7I=; b=OakDBBcFzXQ9Dh 6hyeNAnPXb4ZMg1Tm+afFMICwHes3E86gNQhBDI3cvhINToLeWTkViNiHc8P/em8Ayi7OLqgDYEex aiMGkEJnKHl/d6jFNgUiCyWvvUBEY3FYdkoO5FgFx0wZ4Y+IEYG3Qbyp1drn60+uufkK0ABicpCj/ RcEFd7OIo+vpVarYuwLOx/kvyw33YIfG5aEHZVXEZ5iwZYgNPZigeufwK41GMVQO6ezZo6QA1MLzV KawO5FLPpWS029gaQyYAO89k6gVCurwh3VWylJs9tQptPqi47ArSD2SfRdlOlS4AU2sZVaWBEyiJp oPt6DF/OgWvwGZZr1hqQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mEKH9-00BU9b-Ob; Thu, 12 Aug 2021 23:38:15 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mEKGz-00BTxg-0j for linux-snps-arc@lists.infradead.org; Thu, 12 Aug 2021 23:38:13 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7766D6112E; Thu, 12 Aug 2021 23:38:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628811484; bh=WwnrEymPtlTXjy10ynCidFxMgHguuIzE/6UZ1pzghrQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=isKycoi2XNHSvdcerZYs00WsF4IWnL5ab2yY6BhAjcr2inMrF6bR8DVcPtADZxM8F AJjsG0M1wX88FKJC28LkQR7tKiD+Bj9DqMWCFa6si6z+T7eHxUA1bdps461M0zUsHJ kAymUno45/Ii8RwiJfwJCwKx0DgIudQuZ96ar1H3Gxppy9ToPKiXS6yPCOMACYOBrm nCXiUVWWbbqCg7xb7NvWybTlWSLsdiceMPphU4knfALUvXHFT4bEB6gF+mSlOAPiTw nOiiBiobX1lQZ8G0/Bf1thsTcjMDL6xfQqiLUylLgcBIj+q9uavsAQq9UWetDcWnmv 5IRDjaJSovhLw== 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 16/19] ARC: mm: support 3 levels of page tables Date: Thu, 12 Aug 2021 16:37:50 -0700 Message-Id: <20210812233753.104217-17-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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210812_163805_137413_3AE4B47D X-CRM114-Status: GOOD ( 19.62 ) X-Spam-Score: -5.4 (-----) X-Spam-Report: Spam detection software, running on the system "bombadil.infradead.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: ARCv2 MMU is software walked and Linux implements 2 levels of paging: pgd/pte. Forthcoming hw will have multiple levels, so this change preps mm code for same. It is also fun to try multi levels even [...] Content analysis details: (-5.4 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [198.145.29.99 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 -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.2 DKIMWL_WL_HIGH DKIMwl.org - High trust sender X-BeenThere: linux-snps-arc@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux on Synopsys ARC Processors List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-snps-arc" Errors-To: linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org ARCv2 MMU is software walked and Linux implements 2 levels of paging: pgd/pte. Forthcoming hw will have multiple levels, so this change preps mm code for same. It is also fun to try multi levels even on soft-walked code to ensure generic mm code is robust to handle. overview diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 59d5b2a179f6..43cb8aaf57a2 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -314,6 +314,10 @@ config ARC_HUGEPAGE_16M endchoice +config PGTABLE_LEVELS + int "Number of Page table levels" + default 2 + config ARC_COMPACT_IRQ_LEVELS depends on ISA_ARCOMPACT bool "Setup Timer IRQ as high Priority" diff --git a/arch/arc/include/asm/page.h b/arch/arc/include/asm/page.h index 28ed82b1800f..5d7899d87c08 100644 --- a/arch/arc/include/asm/page.h +++ b/arch/arc/include/asm/page.h @@ -41,6 +41,17 @@ typedef struct { #define pgd_val(x) ((x).pgd) #define __pgd(x) ((pgd_t) { (x) }) +#if CONFIG_PGTABLE_LEVELS > 2 + +typedef struct { + unsigned long pmd; +} pmd_t; + +#define pmd_val(x) ((x).pmd) +#define __pmd(x) ((pmd_t) { (x) }) + +#endif + typedef struct { #ifdef CONFIG_ARC_HAS_PAE40 unsigned long long pte; diff --git a/arch/arc/include/asm/pgalloc.h b/arch/arc/include/asm/pgalloc.h index 0cde9e5eefd7..781620d2e86f 100644 --- a/arch/arc/include/asm/pgalloc.h +++ b/arch/arc/include/asm/pgalloc.h @@ -70,6 +70,17 @@ static inline pgd_t *pgd_alloc(struct mm_struct *mm) return ret; } +#if CONFIG_PGTABLE_LEVELS > 2 + +static inline void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmdp) +{ + set_pud(pudp, __pud((unsigned long)pmdp)); +} + +#define __pmd_free_tlb(tlb, pmd, addr) pmd_free((tlb)->mm, pmd) + +#endif + #define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, pte) #endif /* _ASM_ARC_PGALLOC_H */ diff --git a/arch/arc/include/asm/pgtable-levels.h b/arch/arc/include/asm/pgtable-levels.h index 8ece75335bb5..1c2f022d4ad0 100644 --- a/arch/arc/include/asm/pgtable-levels.h +++ b/arch/arc/include/asm/pgtable-levels.h @@ -10,6 +10,8 @@ #ifndef _ASM_ARC_PGTABLE_LEVELS_H #define _ASM_ARC_PGTABLE_LEVELS_H +#if CONFIG_PGTABLE_LEVELS == 2 + /* * 2 level paging setup for software walked MMUv3 (ARC700) and MMUv4 (HS) * @@ -37,16 +39,38 @@ #define PGDIR_SHIFT 21 #endif -#define PGDIR_SIZE BIT(PGDIR_SHIFT) /* vaddr span, not PDG sz */ -#define PGDIR_MASK (~(PGDIR_SIZE - 1)) +#else + +/* + * A default 3 level paging testing setup in software walked MMU + * MMUv4 (8K page): <4> : <7> : <8> : <13> + */ +#define PGDIR_SHIFT 28 +#if CONFIG_PGTABLE_LEVELS > 2 +#define PMD_SHIFT 21 +#endif + +#endif +#define PGDIR_SIZE BIT(PGDIR_SHIFT) +#define PGDIR_MASK (~(PGDIR_SIZE - 1)) #define PTRS_PER_PGD BIT(32 - PGDIR_SHIFT) -#define PTRS_PER_PTE BIT(PGDIR_SHIFT - PAGE_SHIFT) +#if CONFIG_PGTABLE_LEVELS > 2 +#define PMD_SIZE BIT(PMD_SHIFT) +#define PMD_MASK (~(PMD_SIZE - 1)) +#define PTRS_PER_PMD BIT(PGDIR_SHIFT - PMD_SHIFT) +#endif + +#define PTRS_PER_PTE BIT(PMD_SHIFT - PAGE_SHIFT) #ifndef __ASSEMBLY__ +#if CONFIG_PGTABLE_LEVELS > 2 +#include +#else #include +#endif /* * 1st level paging: pgd @@ -57,9 +81,35 @@ #define pgd_ERROR(e) \ pr_crit("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e)) +#if CONFIG_PGTABLE_LEVELS > 2 + +/* In 3 level paging, pud_* macros work on pgd */ +#define pud_none(x) (!pud_val(x)) +#define pud_bad(x) ((pud_val(x) & ~PAGE_MASK)) +#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)) +#define pud_page(pud) virt_to_page(pud_pgtable(pud)) +#define set_pud(pudp, pud) (*(pudp) = pud) + +/* + * 2nd level paging: pmd + */ +#define pmd_ERROR(e) \ + pr_crit("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e)) + +#define pmd_pfn(pmd) ((pmd_val(pmd) & PMD_MASK) >> PAGE_SHIFT) +#define pfn_pmd(pfn,prot) __pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot)) +#define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot) + +#endif + /* - * Due to the strange way generic pgtable level folding works, in a 2 level - * setup, pmd_val() returns pgd, so these pmd_* macros actually work on pgd + * Due to the strange way generic pgtable level folding works, the pmd_* macros + * - are valid even for 2 levels (which supposedly only has pgd - pte) + * - behave differently for 2 vs. 3 + * In 2 level paging (pgd -> pte), pmd_* macros work on pgd + * 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)) @@ -70,6 +120,9 @@ #define set_pmd(pmdp, pmd) (*(pmdp) = pmd) #define pmd_pgtable(pmd) ((pgtable_t) pmd_page_vaddr(pmd)) +/* + * 3rd level paging: pte + */ #define pte_ERROR(e) \ pr_crit("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e)) diff --git a/arch/arc/include/asm/processor.h b/arch/arc/include/asm/processor.h index e4031ecd3c8c..f28afcf5c6d1 100644 --- a/arch/arc/include/asm/processor.h +++ b/arch/arc/include/asm/processor.h @@ -93,7 +93,7 @@ extern unsigned int get_wchan(struct task_struct *p); #define VMALLOC_START (PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20)) /* 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter (see asm/highmem.h) */ -#define VMALLOC_SIZE ((CONFIG_ARC_KVADDR_SIZE << 20) - PGDIR_SIZE * 4) +#define VMALLOC_SIZE ((CONFIG_ARC_KVADDR_SIZE << 20) - PMD_SIZE * 4) #define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE) diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c index 41f154320964..8da2f0ad8c69 100644 --- a/arch/arc/mm/fault.c +++ b/arch/arc/mm/fault.c @@ -39,6 +39,8 @@ noinline static int handle_kernel_vaddr_fault(unsigned long address) if (!pgd_present(*pgd_k)) goto bad_area; + set_pgd(pgd, *pgd_k); + p4d = p4d_offset(pgd, address); p4d_k = p4d_offset(pgd_k, address); if (!p4d_present(*p4d_k)) @@ -49,6 +51,8 @@ noinline static int handle_kernel_vaddr_fault(unsigned long address) if (!pud_present(*pud_k)) goto bad_area; + set_pud(pud, *pud_k); + pmd = pmd_offset(pud, address); pmd_k = pmd_offset(pud_k, address); if (!pmd_present(*pmd_k)) diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c index 46ad9aee7a73..f7ba2a5d5ec8 100644 --- a/arch/arc/mm/init.c +++ b/arch/arc/mm/init.c @@ -191,6 +191,7 @@ void __init mem_init(void) highmem_init(); BUILD_BUG_ON((PTRS_PER_PGD * sizeof(pgd_t)) > PAGE_SIZE); + BUILD_BUG_ON((PTRS_PER_PMD * sizeof(pmd_t)) > PAGE_SIZE); BUILD_BUG_ON((PTRS_PER_PTE * sizeof(pte_t)) > PAGE_SIZE); } diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c index b68d5798327b..352abb35a2ad 100644 --- a/arch/arc/mm/tlb.c +++ b/arch/arc/mm/tlb.c @@ -658,8 +658,8 @@ char *arc_mmu_mumbojumbo(int cpu_id, char *buf, int len) IS_USED_CFG(CONFIG_TRANSPARENT_HUGEPAGE)); n += scnprintf(buf + n, len - n, - "MMU [v%x]\t: %dk PAGE, %sJTLB %d (%dx%d), uDTLB %d, uITLB %d%s%s\n", - p_mmu->ver, p_mmu->pg_sz_k, super_pg, + "MMU [v%x]\t: %dk PAGE, %s, swalk %d lvl, JTLB %d (%dx%d), uDTLB %d, uITLB %d%s%s\n", + p_mmu->ver, p_mmu->pg_sz_k, super_pg, CONFIG_PGTABLE_LEVELS, p_mmu->sets * p_mmu->ways, p_mmu->sets, p_mmu->ways, p_mmu->u_dtlb, p_mmu->u_itlb, IS_AVAIL2(p_mmu->pae, ", PAE40 ", CONFIG_ARC_HAS_PAE40)); diff --git a/arch/arc/mm/tlbex.S b/arch/arc/mm/tlbex.S index c4a5f16444ce..5f57eba1089d 100644 --- a/arch/arc/mm/tlbex.S +++ b/arch/arc/mm/tlbex.S @@ -173,6 +173,15 @@ ex_saved_reg1: tst r3, r3 bz do_slow_path_pf ; if no Page Table, do page fault +#if CONFIG_PGTABLE_LEVELS > 2 + lsr r0, r2, PMD_SHIFT ; Bits for indexing into PMD + and r0, r0, (PTRS_PER_PMD - 1) + ld.as r1, [r3, r0] ; PMD entry + tst r1, r1 + bz do_slow_path_pf + mov r3, r1 +#endif + #ifdef CONFIG_TRANSPARENT_HUGEPAGE and.f 0, r3, _PAGE_HW_SZ ; Is this Huge PMD (thp) add2.nz r1, r1, r0