From patchwork Tue Dec 6 14:47:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13065948 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9DE91C4708E for ; Tue, 6 Dec 2022 14:53:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235166AbiLFOxZ (ORCPT ); Tue, 6 Dec 2022 09:53:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46950 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235295AbiLFOwR (ORCPT ); Tue, 6 Dec 2022 09:52:17 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D7F22EF46 for ; Tue, 6 Dec 2022 06:49:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1670338155; 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=S55iuEpc5qfmZI4kjI1L5Xd1aSq5tK8vVuUg2fWhjB8=; b=HBFgtJukWWYOPkAfbR8h7hUoJF8NzvwoHveLN1mCKmonoyzszDlUaULMhYM5VFoX9urTiN 1l8Ds/zdpWjX1qGZC8ZP9C2AG/B8wRjdkcjkIKiJFNJc5AY9YtuQwFbv9StBasS2CofGhd qSogB6EbdrPTLVEzpQOOkyLF5eQJAns= 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-653-XPdnQXyyME2wCbAHNgP7hg-1; Tue, 06 Dec 2022 09:49:10 -0500 X-MC-Unique: XPdnQXyyME2wCbAHNgP7hg-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 90E00800159; Tue, 6 Dec 2022 14:49:08 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.193.173]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9CE0B492B0D; Tue, 6 Dec 2022 14:49:02 +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 , Geert Uytterhoeven , Greg Ungerer Subject: [PATCH mm-unstable RFC 10/26] m68k/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE Date: Tue, 6 Dec 2022 15:47:14 +0100 Message-Id: <20221206144730.163732-11-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 Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.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 is effectively unused. While at it, make sure for sun3 that the valid bit never gets set by properly masking it off and mask the type in __swp_entry(). Cc: Geert Uytterhoeven Cc: Greg Ungerer Signed-off-by: David Hildenbrand --- arch/m68k/include/asm/mcf_pgtable.h | 36 ++++++++++++++++++++-- arch/m68k/include/asm/motorola_pgtable.h | 38 +++++++++++++++++++++-- arch/m68k/include/asm/sun3_pgtable.h | 39 ++++++++++++++++++++++-- 3 files changed, 104 insertions(+), 9 deletions(-) diff --git a/arch/m68k/include/asm/mcf_pgtable.h b/arch/m68k/include/asm/mcf_pgtable.h index b619b22823f8..3f8f4d0e66dd 100644 --- a/arch/m68k/include/asm/mcf_pgtable.h +++ b/arch/m68k/include/asm/mcf_pgtable.h @@ -46,6 +46,9 @@ #define _CACHEMASK040 (~0x060) #define _PAGE_GLOBAL040 0x400 /* 68040 global bit, used for kva descs */ +/* We borrow bit 7 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE 0x080 + /* * Externally used page protection values. */ @@ -254,15 +257,42 @@ static inline pte_t pte_mkcache(pte_t pte) extern pgd_t kernel_pg_dir[PTRS_PER_PGD]; /* - * Encode and de-code a swap entry (must be !pte_none(e) && !pte_present(e)) + * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that + * are !pte_none() && !pte_present(). + * + * Format of swap PTEs: + * + * 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 + * <------------------ offset -------------> 0 0 0 E <-- type ---> + * + * E is the exclusive marker that is not stored in swap entries. */ -#define __swp_type(x) ((x).val & 0xFF) +#define __swp_type(x) ((x).val & 0x7f) #define __swp_offset(x) ((x).val >> 11) -#define __swp_entry(typ, off) ((swp_entry_t) { (typ) | \ +#define __swp_entry(typ, off) ((swp_entry_t) { ((typ) & 0x7f) | \ (off << 11) }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) #define __swp_entry_to_pte(x) (__pte((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) +{ + pte_val(pte) |= _PAGE_SWP_EXCLUSIVE; + return pte; +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE; + return pte; +} + #define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT) #define pmd_page(pmd) (pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)) diff --git a/arch/m68k/include/asm/motorola_pgtable.h b/arch/m68k/include/asm/motorola_pgtable.h index 7ac3d64c6b33..02896027c781 100644 --- a/arch/m68k/include/asm/motorola_pgtable.h +++ b/arch/m68k/include/asm/motorola_pgtable.h @@ -41,6 +41,9 @@ #define _PAGE_PROTNONE 0x004 +/* We borrow bit 11 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE 0x800 + #ifndef __ASSEMBLY__ /* This is the cache mode to be used for pages containing page descriptors for @@ -169,12 +172,41 @@ static inline pte_t pte_mkcache(pte_t pte) #define swapper_pg_dir kernel_pg_dir extern pgd_t kernel_pg_dir[128]; -/* Encode and de-code a swap entry (must be !pte_none(e) && !pte_present(e)) */ -#define __swp_type(x) (((x).val >> 4) & 0xff) +/* + * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that + * are !pte_none() && !pte_present(). + * + * Format of swap PTEs: + * + * 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 + * <----------------- offset ------------> E <-- type ---> 0 0 0 0 + * + * E is the exclusive marker that is not stored in swap entries. + */ +#define __swp_type(x) (((x).val >> 4) & 0x7f) #define __swp_offset(x) ((x).val >> 12) -#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 4) | ((offset) << 12) }) +#define __swp_entry(type, offset) ((swp_entry_t) { (((type) & 0x7f) << 4) | ((offset) << 12) }) #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) +{ + pte_val(pte) |= _PAGE_SWP_EXCLUSIVE; + return pte; +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE; + return pte; +} + #endif /* !__ASSEMBLY__ */ #endif /* _MOTOROLA_PGTABLE_H */ diff --git a/arch/m68k/include/asm/sun3_pgtable.h b/arch/m68k/include/asm/sun3_pgtable.h index 90d57e537eb1..5e03ce4fd8d5 100644 --- a/arch/m68k/include/asm/sun3_pgtable.h +++ b/arch/m68k/include/asm/sun3_pgtable.h @@ -71,6 +71,9 @@ #define SUN3_PMD_MASK (0x0000003F) #define SUN3_PMD_MAGIC (0x0000002B) +/* We borrow bit 6 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE 0x040 + #ifndef __ASSEMBLY__ /* @@ -152,12 +155,42 @@ static inline pte_t pte_mkcache(pte_t pte) { return pte; } extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; extern pgd_t kernel_pg_dir[PTRS_PER_PGD]; -/* Macros to (de)construct the fake PTEs representing swap pages. */ -#define __swp_type(x) ((x).val & 0x7F) +/* + * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that + * are !pte_none() && !pte_present(). + * + * Format of swap PTEs: + * + * 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 + * 0 <--------------------- offset ----------------> E <- type --> + * + * E is the exclusive marker that is not stored in swap entries. + */ +#define __swp_type(x) ((x).val & 0x3f) #define __swp_offset(x) (((x).val) >> 7) -#define __swp_entry(type,offset) ((swp_entry_t) { ((type) | ((offset) << 7)) }) +#define __swp_entry(type,offset) ((swp_entry_t) { (((type) & 0x3f) | \ + (((offset) << 7) & ~SUN3_PAGE_VALID)) }) #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) +{ + pte_val(pte) |= _PAGE_SWP_EXCLUSIVE; + return pte; +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE; + return pte; +} + #endif /* !__ASSEMBLY__ */ #endif /* !_SUN3_PGTABLE_H */