From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C20213C1F for ; Tue, 18 Feb 2025 04:48:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739854086; cv=none; b=BxUe8IMzlcn1hE5H9WFACtLhmXqbiQ0ap7ojp0onyhibTPTMIsPQB3a/oqdz3EG02Rrxj//3Uy3i5Crt0h8Coph1Y22OGt8VkzwO9AiStkibUvj5h5Q786bWDbLxkGQwacaZsMAhURx8zn1GzAV1HpnNfDHVYs6hoqysUZP9P04= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739854086; c=relaxed/simple; bh=dwTthdnU0StO7u98VptzcttTbDALR2L0zV1cEm78nu0=; h=Date:To:From:Subject:Message-Id; b=XopBDPocuwR7tLAEWCUw5IiaJrkSjKei9e9PeDQwiGA4KTTmzWUYoXgcasdXXvjwQSjDJzUNMsbMIPs4te1GfxctdJoVpVIuj+t3ym8ee++aGRvNGbahsWTv6GvHRN9ZKe2tmL7ohBAB2LNVYoia6ET4EzCcFvEKbtwbty0XJGw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=duH+Q7/e; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="duH+Q7/e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F8BCC4CEE2; Tue, 18 Feb 2025 04:48:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1739854086; bh=dwTthdnU0StO7u98VptzcttTbDALR2L0zV1cEm78nu0=; h=Date:To:From:Subject:From; b=duH+Q7/eXsQoGMnWODuilKlbcTPlyO30qhyxUkJuGKYYkBCoatdGM6m/S7GrPumaX 3C8BzB4Sl2T+cNpt3YX7hd4kOTVbCOf+TFkwZsT67sU+yh1DcjVj1j1tzX5lCGqli/ CRSxzJQbHdnxm1Zzn6m30bR+meoOby+SdhMzWQaE= Date: Mon, 17 Feb 2025 20:48:05 -0800 To: mm-commits@vger.kernel.org,zhang.lyra@gmail.com,willy@infradead.org,will@kernel.org,vishal.l.verma@intel.com,vgoyal@redhat.com,tytso@mit.edu,svens@linux.ibm.com,peterx@redhat.com,npiggin@gmail.com,mpe@ellerman.id.au,logang@deltatee.com,linmiaohe@huawei.com,lina@asahilina.net,kernel@xen0n.name,jhubbard@nvidia.com,jgg@ziepe.ca,jgg@nvidia.com,jack@suse.cz,ira.weiny@intel.com,hch@lst.de,hca@linux.ibm.com,gor@linux.ibm.com,gerald.schaefer@linux.ibm.com,djwong@kernel.org,david@redhat.com,david@fromorbit.com,dave.jiang@intel.com,dave.hansen@linux.intel.com,dan.j.williams@intel.com,chenhuacai@kernel.org,catalin.marinas@arm.com,borntraeger@linux.ibm.com,bhelgaas@google.com,balbirs@nvidia.com,alison.schofield@intel.com,agordeev@linux.ibm.com,apopple@nvidia.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-memory-enhance-insert_page_into_pte_locked-to-create-writable-mappings.patch added to mm-unstable branch Message-Id: <20250218044806.2F8BCC4CEE2@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm/memory: enhance insert_page_into_pte_locked() to create writable mappings has been added to the -mm mm-unstable branch. Its filename is mm-memory-enhance-insert_page_into_pte_locked-to-create-writable-mappings.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memory-enhance-insert_page_into_pte_locked-to-create-writable-mappings.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Alistair Popple Subject: mm/memory: enhance insert_page_into_pte_locked() to create writable mappings Date: Tue, 18 Feb 2025 14:55:28 +1100 In preparation for using insert_page() for DAX, enhance insert_page_into_pte_locked() to handle establishing writable mappings. Recall that DAX returns VM_FAULT_NOPAGE after installing a PTE which bypasses the typical set_pte_range() in finish_fault. Link: https://lkml.kernel.org/r/ee748e555fb0dc190994a0fd59a57b9c43a17dc9.1739850794.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple Suggested-by: Dan Williams Reviewed-by: Dan Williams Acked-by: David Hildenbrand Tested-by: Alison Schofield Cc: Alexander Gordeev Cc: Asahi Lina Cc: Balbir Singh Cc: Bjorn Helgaas Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Christoph Hellwig Cc: Chunyan Zhang Cc: "Darrick J. Wong" Cc: Dave Chinner Cc: Dave Hansen Cc: Dave Jiang Cc: Gerald Schaefer Cc: Heiko Carstens Cc: Huacai Chen Cc: Ira Weiny Cc: Jan Kara Cc: Jason Gunthorpe Cc: Jason Gunthorpe Cc: John Hubbard Cc: Logan Gunthorpe Cc: Matthew Wilcox Cc: Miaohe Lin Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Peter Xu Cc: Sven Schnelle Cc: Ted Ts'o Cc: Vasily Gorbik Cc: Vishal Verma Cc: Vivek Goyal Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton --- mm/memory.c | 39 ++++++++++++++++++++++++++++++--------- 1 file changed, 30 insertions(+), 9 deletions(-) --- a/mm/memory.c~mm-memory-enhance-insert_page_into_pte_locked-to-create-writable-mappings +++ a/mm/memory.c @@ -2126,19 +2126,39 @@ static int validate_page_before_insert(s } static int insert_page_into_pte_locked(struct vm_area_struct *vma, pte_t *pte, - unsigned long addr, struct page *page, pgprot_t prot) + unsigned long addr, struct page *page, + pgprot_t prot, bool mkwrite) { struct folio *folio = page_folio(page); - pte_t pteval; + pte_t pteval = ptep_get(pte); + + if (!pte_none(pteval)) { + if (!mkwrite) + return -EBUSY; + + /* see insert_pfn(). */ + if (pte_pfn(pteval) != page_to_pfn(page)) { + WARN_ON_ONCE(!is_zero_pfn(pte_pfn(pteval))); + return -EFAULT; + } + pteval = maybe_mkwrite(pteval, vma); + pteval = pte_mkyoung(pteval); + if (ptep_set_access_flags(vma, addr, pte, pteval, 1)) + update_mmu_cache(vma, addr, pte); + return 0; + } - if (!pte_none(ptep_get(pte))) - return -EBUSY; /* Ok, finally just insert the thing.. */ pteval = mk_pte(page, prot); if (unlikely(is_zero_folio(folio))) { pteval = pte_mkspecial(pteval); } else { folio_get(folio); + pteval = mk_pte(page, prot); + if (mkwrite) { + pteval = pte_mkyoung(pteval); + pteval = maybe_mkwrite(pte_mkdirty(pteval), vma); + } inc_mm_counter(vma->vm_mm, mm_counter_file(folio)); folio_add_file_rmap_pte(folio, page, vma); } @@ -2147,7 +2167,7 @@ static int insert_page_into_pte_locked(s } static int insert_page(struct vm_area_struct *vma, unsigned long addr, - struct page *page, pgprot_t prot) + struct page *page, pgprot_t prot, bool mkwrite) { int retval; pte_t *pte; @@ -2160,7 +2180,8 @@ static int insert_page(struct vm_area_st pte = get_locked_pte(vma->vm_mm, addr, &ptl); if (!pte) goto out; - retval = insert_page_into_pte_locked(vma, pte, addr, page, prot); + retval = insert_page_into_pte_locked(vma, pte, addr, page, prot, + mkwrite); pte_unmap_unlock(pte, ptl); out: return retval; @@ -2174,7 +2195,7 @@ static int insert_page_in_batch_locked(s err = validate_page_before_insert(vma, page); if (err) return err; - return insert_page_into_pte_locked(vma, pte, addr, page, prot); + return insert_page_into_pte_locked(vma, pte, addr, page, prot, false); } /* insert_pages() amortizes the cost of spinlock operations @@ -2310,7 +2331,7 @@ int vm_insert_page(struct vm_area_struct BUG_ON(vma->vm_flags & VM_PFNMAP); vm_flags_set(vma, VM_MIXEDMAP); } - return insert_page(vma, addr, page, vma->vm_page_prot); + return insert_page(vma, addr, page, vma->vm_page_prot, false); } EXPORT_SYMBOL(vm_insert_page); @@ -2590,7 +2611,7 @@ static vm_fault_t __vm_insert_mixed(stru * result in pfn_t_has_page() == false. */ page = pfn_to_page(pfn_t_to_pfn(pfn)); - err = insert_page(vma, addr, page, pgprot); + err = insert_page(vma, addr, page, pgprot, mkwrite); } else { return insert_pfn(vma, addr, pfn, pgprot, mkwrite); } _ Patches currently in -mm which might be from apopple@nvidia.com are fuse-fix-dax-truncate-punch_hole-fault-path.patch fs-dax-return-unmapped-busy-pages-from-dax_layout_busy_page_range.patch fs-dax-dont-skip-locked-entries-when-scanning-entries.patch fs-dax-refactor-wait-for-dax-idle-page.patch fs-dax-create-a-common-implementation-to-break-dax-layouts.patch fs-dax-always-remove-dax-page-cache-entries-when-breaking-layouts.patch fs-dax-ensure-all-pages-are-idle-prior-to-filesystem-unmount.patch fs-dax-remove-page_mapping_dax_shared-mapping-flag.patch mm-gup-remove-redundant-check-for-pci-p2pdma-page.patch mm-mm_init-move-p2pdma-page-refcount-initialisation-to-p2pdma.patch mm-allow-compound-zone-device-pages.patch mm-memory-enhance-insert_page_into_pte_locked-to-create-writable-mappings.patch mm-memory-add-vmf_insert_page_mkwrite.patch mm-rmap-add-support-for-pud-sized-mappings-to-rmap.patch mm-huge_memory-add-vmf_insert_folio_pud.patch mm-huge_memory-add-vmf_insert_folio_pmd.patch mm-gup-dont-allow-foll_longterm-pinning-of-fs-dax-pages.patch fs-dax-properly-refcount-fs-dax-pages.patch device-dax-properly-refcount-device-dax-pages-when-mapping.patch