From patchwork Tue Dec 6 14:47:26 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13066059 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 D98EEC352A1 for ; Tue, 6 Dec 2022 15:12:25 +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=amQHrqWZTPWcah+PIAgefhGro8nxP9DybSpWJC8Cn24=; b=f67OLH1fLCaEY6 LDQitR6vMFZnBQPah+B8wro1oPmSM29uexHQAyGC2n4cM+S+LdxddCwVt2CtRo+hn+qSrhGxo6Zn+ QK/1CmkLDFWLGdESN5hix+lxd7LTnP1CRInxzc5NrDjbeaz9juR63Pz7YEYr68sE/ev+HxJNW+7MO sEQDNV8McrI6opbn7wJaxxqj8jg5cQLw/5F70CwufvE/exbzjRrXoq5DWUjmGKd6Tto/lotsDa5sL sdKdzayaOTFlgwSpCtVMvJp1sRMV+E34zRd4uCMbGqoHjorphwffVSKn7ZwoXjSo6DuCHEb6RNtYO gboe6hkAnS0FHy9BViNg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p2ZaQ-00C3oW-Jw; Tue, 06 Dec 2022 15:10:23 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1p2ZHC-00BihA-Vy for linux-arm-kernel@lists.infradead.org; Tue, 06 Dec 2022 14:50:34 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1670338229; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zSPmQx9eeeBLx89henBVTxkcK4792UdAD2dJ7TXUl6g=; b=eb0zkp8uL9o4PAHs7jVc9zRZrQabLZYI3RnznxzObTwNMz8GjizoJf2GKOBX2+bkuVYW8N Bca3fEuYrAgx4VoEMn/ahlYCLpiViE6Cj/po1Eft8IL4u5MW+9t6deW1rSjb+SghgNSkfs KvrTOx5z9AAc8bkYcgBq4C+3A7HpwIk= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-495-_YI18AWSMq2fxvTojIwrDQ-1; Tue, 06 Dec 2022 09:50:27 -0500 X-MC-Unique: _YI18AWSMq2fxvTojIwrDQ-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 04ABC101A52A; Tue, 6 Dec 2022 14:50:26 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.193.173]) by smtp.corp.redhat.com (Postfix) with ESMTP id 021C4492B04; Tue, 6 Dec 2022 14:50:19 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: Andrew Morton , Hugh Dickins , John Hubbard , Jason Gunthorpe , Mike Rapoport , Yang Shi , Vlastimil Babka , Nadav Amit , Andrea Arcangeli , Peter Xu , linux-mm@kvack.org, x86@kernel.org, linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, loongarch@lists.linux.dev, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, openrisc@lists.librecores.org, linux-parisc@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, linux-xtensa@linux-xtensa.org, David Hildenbrand , "David S. Miller" Subject: [PATCH mm-unstable RFC 22/26] sparc/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on 64bit Date: Tue, 6 Dec 2022 15:47:26 +0100 Message-Id: <20221206144730.163732-23-david@redhat.com> In-Reply-To: <20221206144730.163732-1-david@redhat.com> References: <20221206144730.163732-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221206_065031_156360_76996BC8 X-CRM114-Status: GOOD ( 15.35 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Let's support __HAVE_ARCH_PTE_SWP_EXCLUSIVE by stealing one bit from the type. Generic MM currently only uses 5 bits for the type (MAX_SWAPFILES_SHIFT), so the stolen bit was effectively unused. While at it, mask the type in __swp_entry(). Cc: "David S. Miller" Signed-off-by: David Hildenbrand --- arch/sparc/include/asm/pgtable_64.h | 38 ++++++++++++++++++++++++++--- 1 file changed, 35 insertions(+), 3 deletions(-) diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h index 3bc9736bddb1..614fdedbb145 100644 --- a/arch/sparc/include/asm/pgtable_64.h +++ b/arch/sparc/include/asm/pgtable_64.h @@ -187,6 +187,9 @@ bool kern_addr_valid(unsigned long addr); #define _PAGE_SZHUGE_4U _PAGE_SZ4MB_4U #define _PAGE_SZHUGE_4V _PAGE_SZ4MB_4V +/* We borrow bit 20 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE _AC(0x0000000000100000,UL) + #ifndef __ASSEMBLY__ pte_t mk_pte_io(unsigned long, pgprot_t, int, unsigned long); @@ -961,18 +964,47 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp); #endif -/* Encode and de-code a swap entry */ -#define __swp_type(entry) (((entry).val >> PAGE_SHIFT) & 0xffUL) +/* + * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that + * are !pte_none() && !pte_present(). + * + * Format of swap PTEs: + * + * 6 6 6 6 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3 + * 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 + * <--------------------------- offset --------------------------- + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * --------------------> E <-- type ---> <------- zeroes --------> + */ +#define __swp_type(entry) (((entry).val >> PAGE_SHIFT) & 0x7fUL) #define __swp_offset(entry) ((entry).val >> (PAGE_SHIFT + 8UL)) #define __swp_entry(type, offset) \ ( (swp_entry_t) \ { \ - (((long)(type) << PAGE_SHIFT) | \ + ((((long)(type) & 0x7fUL) << PAGE_SHIFT) | \ ((long)(offset) << (PAGE_SHIFT + 8UL))) \ } ) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) +#define __HAVE_ARCH_PTE_SWP_EXCLUSIVE +static inline int pte_swp_exclusive(pte_t pte) +{ + return pte_val(pte) & _PAGE_SWP_EXCLUSIVE; +} + +static inline pte_t pte_swp_mkexclusive(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_SWP_EXCLUSIVE); +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_SWP_EXCLUSIVE); +} + int page_in_phys_avail(unsigned long paddr); /*