From nobody Fri Dec 19 19:09:43 2025 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 B68FACD4857 for ; Mon, 25 Sep 2023 18:35:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233426AbjIYSfM (ORCPT ); Mon, 25 Sep 2023 14:35:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233485AbjIYSex (ORCPT ); Mon, 25 Sep 2023 14:34:53 -0400 Received: from pegase1.c-s.fr (pegase1.c-s.fr [93.17.236.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0F121CF8 for ; Mon, 25 Sep 2023 11:34:13 -0700 (PDT) Received: from localhost (mailhub3.si.c-s.fr [192.168.12.233]) by localhost (Postfix) with ESMTP id 4RvWgd1N9Pz9vBQ; Mon, 25 Sep 2023 20:32:13 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id a_ig0qg1M75u; Mon, 25 Sep 2023 20:32:13 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 4RvWg543K3z9vBx; Mon, 25 Sep 2023 20:31:45 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 875B18B763; Mon, 25 Sep 2023 20:31:45 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id 0oZXEeFob9fs; Mon, 25 Sep 2023 20:31:45 +0200 (CEST) Received: from PO20335.IDSI0.si.c-s.fr (unknown [192.168.232.137]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 5CE7D8B7A7; Mon, 25 Sep 2023 20:31:44 +0200 (CEST) Received: from PO20335.IDSI0.si.c-s.fr (localhost [127.0.0.1]) by PO20335.IDSI0.si.c-s.fr (8.17.1/8.16.1) with ESMTPS id 38PIVaA71499252 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Mon, 25 Sep 2023 20:31:36 +0200 Received: (from chleroy@localhost) by PO20335.IDSI0.si.c-s.fr (8.17.1/8.17.1/Submit) id 38PIVa5v1499251; Mon, 25 Sep 2023 20:31:36 +0200 X-Authentication-Warning: PO20335.IDSI0.si.c-s.fr: chleroy set sender to christophe.leroy@csgroup.eu using -f From: Christophe Leroy To: Michael Ellerman , Nicholas Piggin Cc: Christophe Leroy , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: [PATCH v2 30/37] powerpc/e500: Introduce _PAGE_READ and remove _PAGE_USER Date: Mon, 25 Sep 2023 20:31:44 +0200 Message-ID: <0849ab6bf7ae2af23f94b0457fa40d0ea3983fe4.1695659959.git.christophe.leroy@csgroup.eu> X-Mailer: git-send-email 2.41.0 In-Reply-To: References: MIME-Version: 1.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1695666676; l=6056; i=christophe.leroy@csgroup.eu; s=20211009; h=from:subject:message-id; bh=+yAU856OIxw+JvcrrlMBmiWVWQ85xnwsaQE3DVUWpKI=; b=cCBZ8XFteq1dmzjy9TDdpTKvw0JXcU0cmvWXqTRbr6Ny5aAlko3Js1X2nH6btsfykt8POmlT8 Va4u5VQnPp5Cy0H2NqCYEzd3uVegjIWW1wmrRIhatejhMvHQia7Mtyt X-Developer-Key: i=christophe.leroy@csgroup.eu; a=ed25519; pk=HIzTzUj91asvincQGOFx6+ZF5AoUuP9GdOtQChs7Mm0= Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" e500 MMU has 6 page protection bits: - R, W, X for supervisor - R, W, X for user It means that it can support X without R. To do that, _PAGE_READ flag is needed. With 32 bits PTE there is no bit available for it in PTE. On the other hand the only real use of _PAGE_USER is to implement PAGE_NONE by clearing _PAGE_USER. As _PAGE_NONE can also be implemented by clearing _PAGE_READ, remove _PAGE_USER and add _PAGE_READ. Move _PAGE_PRESENT into bit 30 so that _PAGE_READ can match SR bit. With 64 bits PTE _PAGE_USER is already the combination of SR and UR so all we need to do is to rename it _PAGE_READ. Signed-off-by: Christophe Leroy --- arch/powerpc/include/asm/nohash/32/pte-85xx.h | 22 ++++--------------- arch/powerpc/include/asm/nohash/pte-e500.h | 20 ++++++++--------- arch/powerpc/kernel/head_85xx.S | 10 ++++----- 3 files changed, 18 insertions(+), 34 deletions(-) diff --git a/arch/powerpc/include/asm/nohash/32/pte-85xx.h b/arch/powerpc/i= nclude/asm/nohash/32/pte-85xx.h index 462acf69e302..653a342d3b25 100644 --- a/arch/powerpc/include/asm/nohash/32/pte-85xx.h +++ b/arch/powerpc/include/asm/nohash/32/pte-85xx.h @@ -17,9 +17,9 @@ */ =20 /* Definitions for FSL Book-E Cores */ -#define _PAGE_PRESENT 0x00001 /* S: PTE contains a translation */ -#define _PAGE_USER 0x00002 /* S: User page (maps to UR) */ -#define _PAGE_RW 0x00004 /* S: Write permission (SW) */ +#define _PAGE_READ 0x00001 /* H: Read permission (SR) */ +#define _PAGE_PRESENT 0x00002 /* S: PTE contains a translation */ +#define _PAGE_WRITE 0x00004 /* S: Write permission (SW) */ #define _PAGE_DIRTY 0x00008 /* S: Page dirty */ #define _PAGE_EXEC 0x00010 /* H: SX permission */ #define _PAGE_ACCESSED 0x00020 /* S: Page referenced */ @@ -31,13 +31,6 @@ #define _PAGE_WRITETHRU 0x00400 /* H: W bit */ #define _PAGE_SPECIAL 0x00800 /* S: Special page */ =20 -#define _PAGE_WRITE _PAGE_RW - -#define _PAGE_KERNEL_RO 0 -#define _PAGE_KERNEL_ROX _PAGE_EXEC -#define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW) -#define _PAGE_KERNEL_RWX (_PAGE_DIRTY | _PAGE_RW | _PAGE_EXEC) - /* No page size encoding in the linux PTE */ #define _PAGE_PSIZE 0 =20 @@ -63,14 +56,7 @@ #define _PAGE_BASE (_PAGE_BASE_NC) #endif =20 -/* Permission masks used to generate the __P and __S table */ -#define PAGE_NONE __pgprot(_PAGE_BASE) -#define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW) -#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_= EXEC) -#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER) -#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) -#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER) -#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) +#include =20 #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_NOHASH_32_PTE_FSL_85xx_H */ diff --git a/arch/powerpc/include/asm/nohash/pte-e500.h b/arch/powerpc/incl= ude/asm/nohash/pte-e500.h index b775c7d465a4..31d2c3ea7df8 100644 --- a/arch/powerpc/include/asm/nohash/pte-e500.h +++ b/arch/powerpc/include/asm/nohash/pte-e500.h @@ -48,14 +48,19 @@ =20 /* "Higher level" linux bit combinations */ #define _PAGE_EXEC (_PAGE_BAP_SX | _PAGE_BAP_UX) /* .. and was cache clea= ned */ -#define _PAGE_RW (_PAGE_BAP_SW | _PAGE_BAP_UW) /* User write permission */ +#define _PAGE_READ (_PAGE_BAP_SR | _PAGE_BAP_UR) /* User read permission = */ +#define _PAGE_WRITE (_PAGE_BAP_SW | _PAGE_BAP_UW) /* User write permissio= n */ + #define _PAGE_KERNEL_RW (_PAGE_BAP_SW | _PAGE_BAP_SR | _PAGE_DIRTY) #define _PAGE_KERNEL_RO (_PAGE_BAP_SR) #define _PAGE_KERNEL_RWX (_PAGE_BAP_SW | _PAGE_BAP_SR | _PAGE_DIRTY | _PAG= E_BAP_SX) #define _PAGE_KERNEL_ROX (_PAGE_BAP_SR | _PAGE_BAP_SX) -#define _PAGE_USER (_PAGE_BAP_UR | _PAGE_BAP_SR) /* Can be read */ =20 -#define _PAGE_WRITE _PAGE_RW +#define _PAGE_NA 0 +#define _PAGE_RO _PAGE_READ +#define _PAGE_ROX (_PAGE_READ | _PAGE_BAP_UX) +#define _PAGE_RW (_PAGE_READ | _PAGE_WRITE) +#define _PAGE_RWX (_PAGE_READ | _PAGE_WRITE | _PAGE_BAP_UX) =20 #define _PAGE_SPECIAL _PAGE_SW0 =20 @@ -90,14 +95,7 @@ #define _PAGE_BASE (_PAGE_BASE_NC) #endif =20 -/* Permission masks used to generate the __P and __S table */ -#define PAGE_NONE __pgprot(_PAGE_BASE) -#define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW) -#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_= BAP_UX) -#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER) -#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_BAP_UX) -#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER) -#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_BAP_UX) +#include =20 #ifndef __ASSEMBLY__ static inline pte_t pte_mkexec(pte_t pte) diff --git a/arch/powerpc/kernel/head_85xx.S b/arch/powerpc/kernel/head_85x= x.S index 594756a62c8e..3739d5a281a7 100644 --- a/arch/powerpc/kernel/head_85xx.S +++ b/arch/powerpc/kernel/head_85xx.S @@ -485,10 +485,10 @@ END_BTB_FLUSH_SECTION */ mfspr r12,SPRN_ESR #ifdef CONFIG_PTE_64BIT - li r13,_PAGE_PRESENT + li r13,_PAGE_PRESENT|_PAGE_BAP_SR oris r13,r13,_PAGE_ACCESSED@h #else - li r13,_PAGE_PRESENT|_PAGE_ACCESSED + li r13,_PAGE_PRESENT|_PAGE_READ|_PAGE_ACCESSED #endif rlwimi r13,r12,11,29,29 =20 @@ -783,15 +783,15 @@ BEGIN_MMU_FTR_SECTION mtspr SPRN_MAS7, r10 END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS) #else - li r10, (_PAGE_EXEC | _PAGE_PRESENT) + li r10, (_PAGE_EXEC | _PAGE_READ) mr r13, r11 rlwimi r10, r11, 31, 29, 29 /* extract _PAGE_DIRTY into SW */ and r12, r11, r10 - andi. r10, r11, _PAGE_USER /* Test for _PAGE_USER */ + mcrf cr0, cr5 /* Test for user page */ slwi r10, r12, 1 or r10, r10, r12 rlwinm r10, r10, 0, ~_PAGE_EXEC /* Clear SX on user pages */ - iseleq r12, r12, r10 + isellt r12, r10, r12 rlwimi r13, r12, 0, 20, 31 /* Get RPN from PTE, merge w/ perms */ mtspr SPRN_MAS3, r13 #endif --=20 2.41.0