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Message-ID: <5ea33aec-86f8-489c-937b-77a53fca20ce@arm.com>
Date: Mon, 18 Dec 2023 15:56:23 +0000
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Subject: Re: [PATCH v1 08/39] mm/memory: page_add_file_rmap() ->
 folio_add_file_rmap_[pte|pmd]()
Content-Language: en-GB
To: David Hildenbrand <david@redhat.com>, linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
 "Matthew Wilcox (Oracle)" <willy@infradead.org>,
 Hugh Dickins <hughd@google.com>, Yin Fengwei <fengwei.yin@intel.com>,
 Mike Kravetz <mike.kravetz@oracle.com>, Muchun Song <muchun.song@linux.dev>,
 Peter Xu <peterx@redhat.com>
References: <20231211155652.131054-1-david@redhat.com>
 <20231211155652.131054-9-david@redhat.com>
From: Ryan Roberts <ryan.roberts@arm.com>
In-Reply-To: <20231211155652.131054-9-david@redhat.com>
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On 11/12/2023 15:56, David Hildenbrand wrote:
> Let's convert insert_page_into_pte_locked() and do_set_pmd(). While at it,
> perform some folio conversion.
> 
> Reviewed-by: Yin Fengwei <fengwei.yin@intel.com>
> Signed-off-by: David Hildenbrand <david@redhat.com>

Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>

> ---
>  mm/memory.c | 14 ++++++++------
>  1 file changed, 8 insertions(+), 6 deletions(-)
> 
> diff --git a/mm/memory.c b/mm/memory.c
> index 6a5540ba3c65..70754fd65788 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -1859,12 +1859,14 @@ static int validate_page_before_insert(struct page *page)
>  static int insert_page_into_pte_locked(struct vm_area_struct *vma, pte_t *pte,
>  			unsigned long addr, struct page *page, pgprot_t prot)
>  {
> +	struct folio *folio = page_folio(page);
> +
>  	if (!pte_none(ptep_get(pte)))
>  		return -EBUSY;
>  	/* Ok, finally just insert the thing.. */
> -	get_page(page);
> +	folio_get(folio);
>  	inc_mm_counter(vma->vm_mm, mm_counter_file(page));
> -	page_add_file_rmap(page, vma, false);
> +	folio_add_file_rmap_pte(folio, page, vma);
>  	set_pte_at(vma->vm_mm, addr, pte, mk_pte(page, prot));
>  	return 0;
>  }
> @@ -4409,6 +4411,7 @@ static void deposit_prealloc_pte(struct vm_fault *vmf)
>  
>  vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
>  {
> +	struct folio *folio = page_folio(page);
>  	struct vm_area_struct *vma = vmf->vma;
>  	bool write = vmf->flags & FAULT_FLAG_WRITE;
>  	unsigned long haddr = vmf->address & HPAGE_PMD_MASK;
> @@ -4418,8 +4421,7 @@ vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
>  	if (!thp_vma_suitable_order(vma, haddr, PMD_ORDER))
>  		return ret;
>  
> -	page = compound_head(page);
> -	if (compound_order(page) != HPAGE_PMD_ORDER)
> +	if (page != &folio->page || folio_order(folio) != HPAGE_PMD_ORDER)
>  		return ret;
>  
>  	/*
> @@ -4428,7 +4430,7 @@ vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
>  	 * check.  This kind of THP just can be PTE mapped.  Access to
>  	 * the corrupted subpage should trigger SIGBUS as expected.
>  	 */
> -	if (unlikely(PageHasHWPoisoned(page)))
> +	if (unlikely(folio_test_has_hwpoisoned(folio)))
>  		return ret;
>  
>  	/*
> @@ -4452,7 +4454,7 @@ vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
>  		entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
>  
>  	add_mm_counter(vma->vm_mm, mm_counter_file(page), HPAGE_PMD_NR);
> -	page_add_file_rmap(page, vma, true);
> +	folio_add_file_rmap_pmd(folio, page, vma);
>  
>  	/*
>  	 * deposit and withdraw with pmd lock held