Re: [PATCH v4 14/34] powerpc: Convert various functions to use ptdescs

[Mike Rapoport <rppt@kernel.org>]

On Mon, Jun 12, 2023 at 02:04:03PM -0700, Vishal Moola (Oracle) wrote:
> In order to split struct ptdesc from struct page, convert various
> functions to use ptdescs.
> 
> Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>

Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>

> ---
>  arch/powerpc/mm/book3s64/mmu_context.c | 10 +++---
>  arch/powerpc/mm/book3s64/pgtable.c     | 32 +++++++++---------
>  arch/powerpc/mm/pgtable-frag.c         | 46 +++++++++++++-------------
>  3 files changed, 44 insertions(+), 44 deletions(-)
> 
> diff --git a/arch/powerpc/mm/book3s64/mmu_context.c b/arch/powerpc/mm/book3s64/mmu_context.c
> index c766e4c26e42..1715b07c630c 100644
> --- a/arch/powerpc/mm/book3s64/mmu_context.c
> +++ b/arch/powerpc/mm/book3s64/mmu_context.c
> @@ -246,15 +246,15 @@ static void destroy_contexts(mm_context_t *ctx)
>  static void pmd_frag_destroy(void *pmd_frag)
>  {
>  	int count;
> -	struct page *page;
> +	struct ptdesc *ptdesc;
>  
> -	page = virt_to_page(pmd_frag);
> +	ptdesc = virt_to_ptdesc(pmd_frag);
>  	/* drop all the pending references */
>  	count = ((unsigned long)pmd_frag & ~PAGE_MASK) >> PMD_FRAG_SIZE_SHIFT;
>  	/* We allow PTE_FRAG_NR fragments from a PTE page */
> -	if (atomic_sub_and_test(PMD_FRAG_NR - count, &page->pt_frag_refcount)) {
> -		pgtable_pmd_page_dtor(page);
> -		__free_page(page);
> +	if (atomic_sub_and_test(PMD_FRAG_NR - count, &ptdesc->pt_frag_refcount)) {
> +		pagetable_pmd_dtor(ptdesc);
> +		pagetable_free(ptdesc);
>  	}
>  }
>  
> diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
> index 85c84e89e3ea..1212deeabe15 100644
> --- a/arch/powerpc/mm/book3s64/pgtable.c
> +++ b/arch/powerpc/mm/book3s64/pgtable.c
> @@ -306,22 +306,22 @@ static pmd_t *get_pmd_from_cache(struct mm_struct *mm)
>  static pmd_t *__alloc_for_pmdcache(struct mm_struct *mm)
>  {
>  	void *ret = NULL;
> -	struct page *page;
> +	struct ptdesc *ptdesc;
>  	gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO;
>  
>  	if (mm == &init_mm)
>  		gfp &= ~__GFP_ACCOUNT;
> -	page = alloc_page(gfp);
> -	if (!page)
> +	ptdesc = pagetable_alloc(gfp, 0);
> +	if (!ptdesc)
>  		return NULL;
> -	if (!pgtable_pmd_page_ctor(page)) {
> -		__free_pages(page, 0);
> +	if (!pagetable_pmd_ctor(ptdesc)) {
> +		pagetable_free(ptdesc);
>  		return NULL;
>  	}
>  
> -	atomic_set(&page->pt_frag_refcount, 1);
> +	atomic_set(&ptdesc->pt_frag_refcount, 1);
>  
> -	ret = page_address(page);
> +	ret = ptdesc_address(ptdesc);
>  	/*
>  	 * if we support only one fragment just return the
>  	 * allocated page.
> @@ -331,12 +331,12 @@ static pmd_t *__alloc_for_pmdcache(struct mm_struct *mm)
>  
>  	spin_lock(&mm->page_table_lock);
>  	/*
> -	 * If we find pgtable_page set, we return
> +	 * If we find ptdesc_page set, we return
>  	 * the allocated page with single fragment
>  	 * count.
>  	 */
>  	if (likely(!mm->context.pmd_frag)) {
> -		atomic_set(&page->pt_frag_refcount, PMD_FRAG_NR);
> +		atomic_set(&ptdesc->pt_frag_refcount, PMD_FRAG_NR);
>  		mm->context.pmd_frag = ret + PMD_FRAG_SIZE;
>  	}
>  	spin_unlock(&mm->page_table_lock);
> @@ -357,15 +357,15 @@ pmd_t *pmd_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr)
>  
>  void pmd_fragment_free(unsigned long *pmd)
>  {
> -	struct page *page = virt_to_page(pmd);
> +	struct ptdesc *ptdesc = virt_to_ptdesc(pmd);
>  
> -	if (PageReserved(page))
> -		return free_reserved_page(page);
> +	if (pagetable_is_reserved(ptdesc))
> +		return free_reserved_ptdesc(ptdesc);
>  
> -	BUG_ON(atomic_read(&page->pt_frag_refcount) <= 0);
> -	if (atomic_dec_and_test(&page->pt_frag_refcount)) {
> -		pgtable_pmd_page_dtor(page);
> -		__free_page(page);
> +	BUG_ON(atomic_read(&ptdesc->pt_frag_refcount) <= 0);
> +	if (atomic_dec_and_test(&ptdesc->pt_frag_refcount)) {
> +		pagetable_pmd_dtor(ptdesc);
> +		pagetable_free(ptdesc);
>  	}
>  }
>  
> diff --git a/arch/powerpc/mm/pgtable-frag.c b/arch/powerpc/mm/pgtable-frag.c
> index 20652daa1d7e..8961f1540209 100644
> --- a/arch/powerpc/mm/pgtable-frag.c
> +++ b/arch/powerpc/mm/pgtable-frag.c
> @@ -18,15 +18,15 @@
>  void pte_frag_destroy(void *pte_frag)
>  {
>  	int count;
> -	struct page *page;
> +	struct ptdesc *ptdesc;
>  
> -	page = virt_to_page(pte_frag);
> +	ptdesc = virt_to_ptdesc(pte_frag);
>  	/* drop all the pending references */
>  	count = ((unsigned long)pte_frag & ~PAGE_MASK) >> PTE_FRAG_SIZE_SHIFT;
>  	/* We allow PTE_FRAG_NR fragments from a PTE page */
> -	if (atomic_sub_and_test(PTE_FRAG_NR - count, &page->pt_frag_refcount)) {
> -		pgtable_pte_page_dtor(page);
> -		__free_page(page);
> +	if (atomic_sub_and_test(PTE_FRAG_NR - count, &ptdesc->pt_frag_refcount)) {
> +		pagetable_pte_dtor(ptdesc);
> +		pagetable_free(ptdesc);
>  	}
>  }
>  
> @@ -55,25 +55,25 @@ static pte_t *get_pte_from_cache(struct mm_struct *mm)
>  static pte_t *__alloc_for_ptecache(struct mm_struct *mm, int kernel)
>  {
>  	void *ret = NULL;
> -	struct page *page;
> +	struct ptdesc *ptdesc;
>  
>  	if (!kernel) {
> -		page = alloc_page(PGALLOC_GFP | __GFP_ACCOUNT);
> -		if (!page)
> +		ptdesc = pagetable_alloc(PGALLOC_GFP | __GFP_ACCOUNT, 0);
> +		if (!ptdesc)
>  			return NULL;
> -		if (!pgtable_pte_page_ctor(page)) {
> -			__free_page(page);
> +		if (!pagetable_pte_ctor(ptdesc)) {
> +			pagetable_free(ptdesc);
>  			return NULL;
>  		}
>  	} else {
> -		page = alloc_page(PGALLOC_GFP);
> -		if (!page)
> +		ptdesc = pagetable_alloc(PGALLOC_GFP, 0);
> +		if (!ptdesc)
>  			return NULL;
>  	}
>  
> -	atomic_set(&page->pt_frag_refcount, 1);
> +	atomic_set(&ptdesc->pt_frag_refcount, 1);
>  
> -	ret = page_address(page);
> +	ret = ptdesc_address(ptdesc);
>  	/*
>  	 * if we support only one fragment just return the
>  	 * allocated page.
> @@ -82,12 +82,12 @@ static pte_t *__alloc_for_ptecache(struct mm_struct *mm, int kernel)
>  		return ret;
>  	spin_lock(&mm->page_table_lock);
>  	/*
> -	 * If we find pgtable_page set, we return
> +	 * If we find ptdesc_page set, we return
>  	 * the allocated page with single fragment
>  	 * count.
>  	 */
>  	if (likely(!pte_frag_get(&mm->context))) {
> -		atomic_set(&page->pt_frag_refcount, PTE_FRAG_NR);
> +		atomic_set(&ptdesc->pt_frag_refcount, PTE_FRAG_NR);
>  		pte_frag_set(&mm->context, ret + PTE_FRAG_SIZE);
>  	}
>  	spin_unlock(&mm->page_table_lock);
> @@ -108,15 +108,15 @@ pte_t *pte_fragment_alloc(struct mm_struct *mm, int kernel)
>  
>  void pte_fragment_free(unsigned long *table, int kernel)
>  {
> -	struct page *page = virt_to_page(table);
> +	struct ptdesc *ptdesc = virt_to_ptdesc(table);
>  
> -	if (PageReserved(page))
> -		return free_reserved_page(page);
> +	if (pagetable_is_reserved(ptdesc))
> +		return free_reserved_ptdesc(ptdesc);
>  
> -	BUG_ON(atomic_read(&page->pt_frag_refcount) <= 0);
> -	if (atomic_dec_and_test(&page->pt_frag_refcount)) {
> +	BUG_ON(atomic_read(&ptdesc->pt_frag_refcount) <= 0);
> +	if (atomic_dec_and_test(&ptdesc->pt_frag_refcount)) {
>  		if (!kernel)
> -			pgtable_pte_page_dtor(page);
> -		__free_page(page);
> +			pagetable_pte_dtor(ptdesc);
> +		pagetable_free(ptdesc);
>  	}
>  }
> -- 
> 2.40.1
> 
> 

-- 
Sincerely yours,
Mike.