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 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 7B5BDC3600C for ; Thu, 3 Apr 2025 06:23:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=fOevX9dVP8B9x142UUWyFx0mzsmVnRTWNRfDMowzrP0=; b=2nl3wNPIv9fWp9oU5oPONzetXt 4okt3zAFT6BFD4u0F2t5jVn7hvWT7eX3D5BLPawyxjXUgxslL7rpA4HMwqksCaTQduQGaDJAsHCCF W5xCub1Mwz+2qytve0LOIrkHqtKcNkoyjY/XcF7nSRUbBFP42M6xPl5CM9YB30FuVYBFCY+Ded4O9 hLIgTbYj+VYCyy+M5xI+Tm+PIocrRohgOcQ2JRN/hPhqrmuevc9LfPv3h0CS3qln92uN7ckIas3Dx f7r5hZ4mWv2egRBA+e03bMgTKt6r10kd9q7kO7iXrUD2Djb303b/wz8IKoTL8+rtkvovLOJnBHhX3 ak3akutA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u0Dz2-00000007ubg-0DXk; Thu, 03 Apr 2025 06:23:24 +0000 Received: from nyc.source.kernel.org ([2604:1380:45d1:ec00::3]) by bombadil.infradead.org with esmtps (Exim 4.98.1 #2 (Red Hat Linux)) id 1u0Dvc-00000007uA7-2fxt for linux-arm-kernel@lists.infradead.org; Thu, 03 Apr 2025 06:19:54 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id F3F2EA462BA; Thu, 3 Apr 2025 06:14:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9218C4CEE3; Thu, 3 Apr 2025 06:19:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743661191; bh=IVd8UGsu5sV0jxUV5ZTr4vtRlKqOWafEpnx5MIWbO3s=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KekjkokwWTfjRow/NzSJ1BwYsusDXfqJsoeMmHiG480Y8LjGYy2xbtX61/d+jYFo0 ya8vgFt32OgC+FwXz9kFye9oILceBeNwoQiIH9SOoCg4yPYbatDWUx6LFTZMhESzQs ZHBz3gh2NEK4nQtkmNnkc7F0kWbEitreUEVRM4N7L9ymOjafn5ulUJapDMUA+8D+Hx tVXkc+RI5kyYKqnaNMJaJuGymZdNG3IvvFSodU7r8gaFI2pzZMlRUA5rgwcRAlxcE0 rc2OyW+HMEHtqx3e2bl7ZRB7uAly4C1XcI76oeqveJO3pTpwR1SHWqxMOcGpMNeTuZ OwZvspfkAEtZg== Date: Thu, 3 Apr 2025 09:19:43 +0300 From: Mike Rapoport To: David Woodhouse Cc: Andrew Morton , "Sauerwein, David" , Anshuman Khandual , Ard Biesheuvel , Catalin Marinas , David Hildenbrand , Marc Zyngier , Mark Rutland , Mike Rapoport , Will Deacon , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [RFC PATCH 2/3] mm: Implement for_each_valid_pfn() for CONFIG_FLATMEM Message-ID: References: <20250402201841.3245371-1-dwmw2@infradead.org> <20250402201841.3245371-2-dwmw2@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250402201841.3245371-2-dwmw2@infradead.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250402_231952_739730_165A64E6 X-CRM114-Status: GOOD ( 23.02 ) 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 On Wed, Apr 02, 2025 at 09:18:40PM +0100, David Woodhouse wrote: > From: David Woodhouse > > In the FLATMEM case, the default pfn_valid() just checks that the PFN is > within the range [ ARCH_PFN_OFFSET .. ARCH_PFN_OFFSET + max_mapnr ). > > The for_each_valid_pfn() function can therefore be a simple for() loop > using those as min/max respectively. > > Signed-off-by: David Woodhouse Reviewed-by: Mike Rapoport (Microsoft) > --- > include/asm-generic/memory_model.h | 26 +++++++++++++++++++++++++- > 1 file changed, 25 insertions(+), 1 deletion(-) > > diff --git a/include/asm-generic/memory_model.h b/include/asm-generic/memory_model.h > index a3b5029aebbd..4fe7dd3bc09c 100644 > --- a/include/asm-generic/memory_model.h > +++ b/include/asm-generic/memory_model.h > @@ -30,7 +30,31 @@ static inline int pfn_valid(unsigned long pfn) > return pfn >= pfn_offset && (pfn - pfn_offset) < max_mapnr; > } > #define pfn_valid pfn_valid > -#endif > + > +static inline bool first_valid_pfn(unsigned long *pfn) > +{ > + /* avoid include hell */ > + extern unsigned long max_mapnr; > + unsigned long pfn_offset = ARCH_PFN_OFFSET; > + > + if (*pfn < pfn_offset) { > + *pfn = pfn_offset; > + return true; > + } > + > + if ((*pfn - pfn_offset) < max_mapnr) > + return true; > + > + return false; > +} > + > +#ifndef for_each_valid_pfn > +#define for_each_valid_pfn(pfn, start_pfn, end_pfn) \ > + for (pfn = max_t(unsigned long start_pfn, ARCH_PFN_OFFSET); \ > + pfn < min_t(unsigned long, end_pfn, ARCH_PFN_OFFSET + max_mapnr); \ > + pfn++) > +#endif /* for_each_valid_pfn */ > +#endif /* valid_pfn */ > > #elif defined(CONFIG_SPARSEMEM_VMEMMAP) > > -- > 2.49.0 > -- Sincerely yours, Mike.