From patchwork Wed Feb 5 14:40:30 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leon Romanovsky X-Patchwork-Id: 13961188 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 96A8BC02194 for ; Wed, 5 Feb 2025 14:41:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CEE39280006; Wed, 5 Feb 2025 09:41:32 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C4992280002; Wed, 5 Feb 2025 09:41:32 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A26D4280006; Wed, 5 Feb 2025 09:41:32 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 798D7280002 for ; Wed, 5 Feb 2025 09:41:32 -0500 (EST) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 2F5FD1A0D4F for ; Wed, 5 Feb 2025 14:41:32 +0000 (UTC) X-FDA: 83086154424.11.68C2EFE Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf02.hostedemail.com (Postfix) with ESMTP id 8ECA880015 for ; Wed, 5 Feb 2025 14:41:30 +0000 (UTC) Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=MmYZuNtb; spf=pass (imf02.hostedemail.com: domain of leon@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=leon@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1738766490; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=DIJO+24ad9vDGmaHVsAVu3JrfX9q54SvQz8P9QHl0Fg=; b=1Th35gRxgOYpeUWsILqX+Z+tQ2I9x0W5ImuyUwJMZGAg7WDpxT3WtM/Lu1k2rthql5GQjp yOSRAQBZqt/NS1h5Vv7CSbbZsUDsmlS5PVhSliMS0gUmP5uYZKkka0jlsfT6cEWftZd2NG ySrz5TKG+BfsVlJmLwgHGQOkp3ZCMxs= ARC-Authentication-Results: i=1; imf02.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=MmYZuNtb; spf=pass (imf02.hostedemail.com: domain of leon@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=leon@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1738766490; a=rsa-sha256; cv=none; b=mk3evBpmOCmgc0bt2MFngHRIQyZfT/DUXi0e9tNGfC7sQUM30veLNIyGzaYyzSO814/Kea 7thYAvzD7AWOSk5r2jYwf8Gi90ujiEUEoN8wP25V646tvbhaFWqaaOM2X2JNTvCKFsUF7e bkDAGTii/JJfSlw0wo+PSpD/ZSp7Cqk= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id E6E9F5C5530; Wed, 5 Feb 2025 14:40:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B4761C4CED1; Wed, 5 Feb 2025 14:41:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1738766489; bh=1duzLMAGFBI5eIoee0bClSdhTdn7Gg5VjGv5Oh0QytA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MmYZuNtbS6QLoi6OOv5byqLDz590SF4gxj8qw60jmXERWj1pMQCqXtJjQDU1dtnmJ I49gvJilDg2s2dUa+tqPo5A44RRyvrYFFekDrUfStVtqnREoihzrEiH021FCONs/we I0t/MxA0MfedfNHxZyc9jswRtfPtZHiFYpjEw4N5ttmBIGKihSgtg25SCTf/w3g48q dvG1pC0huUPSeRKdDE/0h7gKxctMvTsLrdZGVDVA5b6/NIBf8c4ELC3f9n6tNZgYq8 n7y21IG/f+wFTBnwUna2sgrwwkMb7tObkmAsllwYyeL4VA5ehl8sGIibNxlNdCB7X0 zopkQxks5Gd1Q== From: Leon Romanovsky To: Christoph Hellwig , Jason Gunthorpe , Robin Murphy Cc: Leon Romanovsky , Jens Axboe , Joerg Roedel , Will Deacon , Sagi Grimberg , Keith Busch , Bjorn Helgaas , Logan Gunthorpe , Yishai Hadas , Shameer Kolothum , Kevin Tian , Alex Williamson , Marek Szyprowski , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Andrew Morton , Jonathan Corbet , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-rdma@vger.kernel.org, iommu@lists.linux.dev, linux-nvme@lists.infradead.org, linux-pci@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, Randy Dunlap Subject: [PATCH v7 10/17] mm/hmm: let users to tag specific PFN with DMA mapped bit Date: Wed, 5 Feb 2025 16:40:30 +0200 Message-ID: X-Mailer: git-send-email 2.48.1 In-Reply-To: References: MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 8ECA880015 X-Stat-Signature: 3uoruqeyz79d6n1koxcbq9ktsz5zjrh1 X-HE-Tag: 1738766490-139558 X-HE-Meta: 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 /tm/GhK9 Hvmtoc1xnNl3I+VWQ/+JinBnG4n8LvmrjCiWOCEPxZtwPMWjgAy8MXeMJVctPi41IY1izyREgTGFKBo0pHeJjkB9MRZLcx5gKkQdj7h4nUeHorPXq3MuF464JUzR/SvZmjEbEJd1+baMHz8/bBzy2+fsYfzLZHoa/duFGUL5Ho3QsnYnh6eUhBnCPfaVG/ifRr8Yv 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: List-Subscribe: List-Unsubscribe: From: Leon Romanovsky Introduce new sticky flag (HMM_PFN_DMA_MAPPED), which isn't overwritten by HMM range fault. Such flag allows users to tag specific PFNs with information if this specific PFN was already DMA mapped. Signed-off-by: Leon Romanovsky --- include/linux/hmm.h | 17 +++++++++++++++ mm/hmm.c | 51 ++++++++++++++++++++++++++++----------------- 2 files changed, 49 insertions(+), 19 deletions(-) diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 126a36571667..a1ddbedc19c0 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -23,6 +23,8 @@ struct mmu_interval_notifier; * HMM_PFN_WRITE - if the page memory can be written to (requires HMM_PFN_VALID) * HMM_PFN_ERROR - accessing the pfn is impossible and the device should * fail. ie poisoned memory, special pages, no vma, etc + * HMM_PFN_DMA_MAPPED - Flag preserved on input-to-output transformation + * to mark that page is already DMA mapped * * On input: * 0 - Return the current state of the page, do not fault it. @@ -36,6 +38,13 @@ enum hmm_pfn_flags { HMM_PFN_VALID = 1UL << (BITS_PER_LONG - 1), HMM_PFN_WRITE = 1UL << (BITS_PER_LONG - 2), HMM_PFN_ERROR = 1UL << (BITS_PER_LONG - 3), + + /* + * Sticky flags, carried from input to output, + * don't forget to update HMM_PFN_INOUT_FLAGS + */ + HMM_PFN_DMA_MAPPED = 1UL << (BITS_PER_LONG - 7), + HMM_PFN_ORDER_SHIFT = (BITS_PER_LONG - 8), /* Input flags */ @@ -57,6 +66,14 @@ static inline struct page *hmm_pfn_to_page(unsigned long hmm_pfn) return pfn_to_page(hmm_pfn & ~HMM_PFN_FLAGS); } +/* + * hmm_pfn_to_phys() - return physical address pointed to by a device entry + */ +static inline phys_addr_t hmm_pfn_to_phys(unsigned long hmm_pfn) +{ + return __pfn_to_phys(hmm_pfn & ~HMM_PFN_FLAGS); +} + /* * hmm_pfn_to_map_order() - return the CPU mapping size order * diff --git a/mm/hmm.c b/mm/hmm.c index 7e0229ae4a5a..da5743f6d854 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -39,13 +39,20 @@ enum { HMM_NEED_ALL_BITS = HMM_NEED_FAULT | HMM_NEED_WRITE_FAULT, }; +enum { + /* These flags are carried from input-to-output */ + HMM_PFN_INOUT_FLAGS = HMM_PFN_DMA_MAPPED, +}; + static int hmm_pfns_fill(unsigned long addr, unsigned long end, struct hmm_range *range, unsigned long cpu_flags) { unsigned long i = (addr - range->start) >> PAGE_SHIFT; - for (; addr < end; addr += PAGE_SIZE, i++) - range->hmm_pfns[i] = cpu_flags; + for (; addr < end; addr += PAGE_SIZE, i++) { + range->hmm_pfns[i] &= HMM_PFN_INOUT_FLAGS; + range->hmm_pfns[i] |= cpu_flags; + } return 0; } @@ -202,8 +209,10 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr, return hmm_vma_fault(addr, end, required_fault, walk); pfn = pmd_pfn(pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT); - for (i = 0; addr < end; addr += PAGE_SIZE, i++, pfn++) - hmm_pfns[i] = pfn | cpu_flags; + for (i = 0; addr < end; addr += PAGE_SIZE, i++, pfn++) { + hmm_pfns[i] &= HMM_PFN_INOUT_FLAGS; + hmm_pfns[i] |= pfn | cpu_flags; + } return 0; } #else /* CONFIG_TRANSPARENT_HUGEPAGE */ @@ -230,14 +239,14 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, unsigned long cpu_flags; pte_t pte = ptep_get(ptep); uint64_t pfn_req_flags = *hmm_pfn; + uint64_t new_pfn_flags = 0; if (pte_none_mostly(pte)) { required_fault = hmm_pte_need_fault(hmm_vma_walk, pfn_req_flags, 0); if (required_fault) goto fault; - *hmm_pfn = 0; - return 0; + goto out; } if (!pte_present(pte)) { @@ -253,16 +262,14 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, cpu_flags = HMM_PFN_VALID; if (is_writable_device_private_entry(entry)) cpu_flags |= HMM_PFN_WRITE; - *hmm_pfn = swp_offset_pfn(entry) | cpu_flags; - return 0; + new_pfn_flags = swp_offset_pfn(entry) | cpu_flags; + goto out; } required_fault = hmm_pte_need_fault(hmm_vma_walk, pfn_req_flags, 0); - if (!required_fault) { - *hmm_pfn = 0; - return 0; - } + if (!required_fault) + goto out; if (!non_swap_entry(entry)) goto fault; @@ -304,11 +311,13 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, pte_unmap(ptep); return -EFAULT; } - *hmm_pfn = HMM_PFN_ERROR; - return 0; + new_pfn_flags = HMM_PFN_ERROR; + goto out; } - *hmm_pfn = pte_pfn(pte) | cpu_flags; + new_pfn_flags = pte_pfn(pte) | cpu_flags; +out: + *hmm_pfn = (*hmm_pfn & HMM_PFN_INOUT_FLAGS) | new_pfn_flags; return 0; fault: @@ -448,8 +457,10 @@ static int hmm_vma_walk_pud(pud_t *pudp, unsigned long start, unsigned long end, } pfn = pud_pfn(pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT); - for (i = 0; i < npages; ++i, ++pfn) - hmm_pfns[i] = pfn | cpu_flags; + for (i = 0; i < npages; ++i, ++pfn) { + hmm_pfns[i] &= HMM_PFN_INOUT_FLAGS; + hmm_pfns[i] |= pfn | cpu_flags; + } goto out_unlock; } @@ -507,8 +518,10 @@ static int hmm_vma_walk_hugetlb_entry(pte_t *pte, unsigned long hmask, } pfn = pte_pfn(entry) + ((start & ~hmask) >> PAGE_SHIFT); - for (; addr < end; addr += PAGE_SIZE, i++, pfn++) - range->hmm_pfns[i] = pfn | cpu_flags; + for (; addr < end; addr += PAGE_SIZE, i++, pfn++) { + range->hmm_pfns[i] &= HMM_PFN_INOUT_FLAGS; + range->hmm_pfns[i] |= pfn | cpu_flags; + } spin_unlock(ptl); return 0;