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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8CAD8C433EF for ; Sat, 9 Apr 2022 11:36:23 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A3EED6B0071; Sat, 9 Apr 2022 07:36:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9C6466B0073; Sat, 9 Apr 2022 07:36:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 867EA6B0074; Sat, 9 Apr 2022 07:36:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0112.hostedemail.com [216.40.44.112]) by kanga.kvack.org (Postfix) with ESMTP id 7090D6B0071 for ; Sat, 9 Apr 2022 07:36:22 -0400 (EDT) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 15DC3183BA09A for ; Sat, 9 Apr 2022 11:36:22 +0000 (UTC) X-FDA: 79337137404.24.3C01745 Received: from pegase2.c-s.fr (pegase2.c-s.fr [93.17.235.10]) by imf13.hostedemail.com (Postfix) with ESMTP id 90FC420002 for ; Sat, 9 Apr 2022 11:36:21 +0000 (UTC) Received: from localhost (mailhub3.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4KbCkC4fZ6z9sTL; Sat, 9 Apr 2022 13:36:19 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase2.c-s.fr ([172.26.127.65]) by localhost (pegase2.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id lY7tFaIkTcqy; Sat, 9 Apr 2022 13:36:19 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase2.c-s.fr (Postfix) with ESMTP id 4KbCkC3V0xz9sT3; Sat, 9 Apr 2022 13:36:19 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 61A1F8B76D; Sat, 9 Apr 2022 13:36:19 +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 xy5JHFm3eEDp; Sat, 9 Apr 2022 13:36:19 +0200 (CEST) Received: from [192.168.203.47] (unknown [192.168.203.47]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 88E408B765; Sat, 9 Apr 2022 13:36:18 +0200 (CEST) Message-ID: <8f1d5ba5-c03e-d222-ffc0-d9a6baea1037@csgroup.eu> Date: Sat, 9 Apr 2022 13:36:17 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH V4 2/7] powerpc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT Content-Language: fr-FR From: Christophe Leroy To: Anshuman Khandual , linux-mm@kvack.org, akpm@linux-foundation.org Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Hellwig , Paul Mackerras , sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org References: <20220407103251.1209606-1-anshuman.khandual@arm.com> <20220407103251.1209606-3-anshuman.khandual@arm.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 90FC420002 X-Rspam-User: Authentication-Results: imf13.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf13.hostedemail.com: domain of christophe.leroy@csgroup.eu designates 93.17.235.10 as permitted sender) smtp.mailfrom=christophe.leroy@csgroup.eu X-Stat-Signature: fb1jawkwm5og8ts59ca4sw95u6fpqj7h X-HE-Tag: 1649504181-979670 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Le 08/04/2022 =C3=A0 14:53, Christophe Leroy a =C3=A9crit=C2=A0: >=20 >=20 > Le 07/04/2022 =C3=A0 12:32, Anshuman Khandual a =C3=A9crit=C2=A0: >> This defines and exports a platform specific custom vm_get_page_prot()= =20 >> via >> subscribing ARCH_HAS_VM_GET_PAGE_PROT. While here, this also localizes >> arch_vm_get_page_prot() as powerpc_vm_get_page_prot() and moves it nea= r >> vm_get_page_prot(). >> >> Cc: Michael Ellerman >> Cc: Paul Mackerras >> Cc: linuxppc-dev@lists.ozlabs.org >> Cc: linux-kernel@vger.kernel.org >> Signed-off-by: Anshuman Khandual >> --- >> =C2=A0 arch/powerpc/Kconfig=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0 |=C2=A0 1 + >> =C2=A0 arch/powerpc/include/asm/mman.h | 12 ------------ >> =C2=A0 arch/powerpc/mm/mmap.c=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0 | 26 ++++++++++++++++++++++++++ >> =C2=A0 3 files changed, 27 insertions(+), 12 deletions(-) >> >> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig >> index 174edabb74fa..eb9b6ddbf92f 100644 >> --- a/arch/powerpc/Kconfig >> +++ b/arch/powerpc/Kconfig >> @@ -140,6 +140,7 @@ config PPC >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 select ARCH_HAS_TICK_BROADCAST=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if=20 >> GENERIC_CLOCKEVENTS_BROADCAST >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 select ARCH_HAS_UACCESS_FLUSHCACHE >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 select ARCH_HAS_UBSAN_SANITIZE_ALL >> +=C2=A0=C2=A0=C2=A0 select ARCH_HAS_VM_GET_PAGE_PROT >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 select ARCH_HAVE_NMI_SAFE_CMPXCHG >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 select ARCH_KEEP_MEMBLOCK >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 select ARCH_MIGHT_HAVE_PC_PARPORT >> diff --git a/arch/powerpc/include/asm/mman.h=20 >> b/arch/powerpc/include/asm/mman.h >> index 7cb6d18f5cd6..1b024e64c8ec 100644 >> --- a/arch/powerpc/include/asm/mman.h >> +++ b/arch/powerpc/include/asm/mman.h >> @@ -24,18 +24,6 @@ static inline unsigned long=20 >> arch_calc_vm_prot_bits(unsigned long prot, >> =C2=A0 } >> =C2=A0 #define arch_calc_vm_prot_bits(prot, pkey)=20 >> arch_calc_vm_prot_bits(prot, pkey) >> -static inline pgprot_t arch_vm_get_page_prot(unsigned long vm_flags) >> -{ >> -#ifdef CONFIG_PPC_MEM_KEYS >> -=C2=A0=C2=A0=C2=A0 return (vm_flags & VM_SAO) ? >> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 __pgprot(_PAGE_SAO | vmfla= g_to_pte_pkey_bits(vm_flags)) : >> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 __pgprot(0 | vmflag_to_pte= _pkey_bits(vm_flags)); >> -#else >> -=C2=A0=C2=A0=C2=A0 return (vm_flags & VM_SAO) ? __pgprot(_PAGE_SAO) := __pgprot(0); >> -#endif >> -} >> -#define arch_vm_get_page_prot(vm_flags) arch_vm_get_page_prot(vm_flag= s) >> - >> =C2=A0 static inline bool arch_validate_prot(unsigned long prot, unsig= ned=20 >> long addr) >> =C2=A0 { >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if (prot & ~(PROT_READ | PROT_WRITE | P= ROT_EXEC | PROT_SEM |=20 >> PROT_SAO)) >> diff --git a/arch/powerpc/mm/mmap.c b/arch/powerpc/mm/mmap.c >> index c475cf810aa8..cd17bd6fa36b 100644 >> --- a/arch/powerpc/mm/mmap.c >> +++ b/arch/powerpc/mm/mmap.c >> @@ -254,3 +254,29 @@ void arch_pick_mmap_layout(struct mm_struct *mm,=20 >> struct rlimit *rlim_stack) >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 mm->get_unmappe= d_area =3D arch_get_unmapped_area_topdown; >> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 } >> =C2=A0 } >> + >> +#ifdef CONFIG_PPC64 >> +static pgprot_t powerpc_vm_get_page_prot(unsigned long vm_flags) >> +{ >> +#ifdef CONFIG_PPC_MEM_KEYS >> +=C2=A0=C2=A0=C2=A0 return (vm_flags & VM_SAO) ? >> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 __pgprot(_PAGE_SAO | vmfla= g_to_pte_pkey_bits(vm_flags)) : >> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 __pgprot(0 | vmflag_to_pte= _pkey_bits(vm_flags)); >> +#else >> +=C2=A0=C2=A0=C2=A0 return (vm_flags & VM_SAO) ? __pgprot(_PAGE_SAO) := __pgprot(0); >> +#endif >> +} >> +#else >> +static pgprot_t powerpc_vm_get_page_prot(unsigned long vm_flags) >> +{ >> +=C2=A0=C2=A0=C2=A0 return __pgprot(0); >> +} >> +#endif /* CONFIG_PPC64 */ >=20 > Can we reduce this forest of #ifdefs and make it more readable ? >=20 > mm/mmap.c is going away with patch=20 > https://patchwork.ozlabs.org/project/linuxppc-dev/patch/d6d849621f821af= 253e777a24eda4c648814a76e.1646847562.git.christophe.leroy@csgroup.eu/=20 >=20 >=20 > So it would be better to add two versions of vm_get_page_prot(), for=20 > instance one in mm/pgtable_64.c and one in mm/pgtable_32.c Indeed, you don't need anything at all for PPC32. All you need to do is select ARCH_HAS_VM_GET_PAGE_PROT if PPC64 And in fact it could even be PPC_BOOK3S_64 instead of PPC64 because=20 CONFIG_PPC_MEM_KEYS depends on PPC_BOOK3S_64 and _PAGE_SAO is 0 on=20 nohash/64. So you can then put it into arch/powerpc/mm/book3s64/pgtable.c >=20 >=20 >> + >> +pgprot_t vm_get_page_prot(unsigned long vm_flags) >> +{ >> +=C2=A0=C2=A0=C2=A0 return __pgprot(pgprot_val(protection_map[vm_flags= & >> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 (V= M_READ|VM_WRITE|VM_EXEC|VM_SHARED)]) | >> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 pgprot_v= al(powerpc_vm_get_page_prot(vm_flags))); >> +} >> +EXPORT_SYMBOL(vm_get_page_prot); >=20 > By the way I'm a bit puzzled with the name powerpc_vm_get_page_prot(),=20 > the name suggests that it's just a powerpc replacement of=20 > vm_get_page_prot(). I'd prefer if it was named __vm_get_page_prot(), it= =20 > would be clearer that it is a complement to vm_get_page_prot() and not = a=20 > remplacement. >=20 > Christophe